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A Step Saving Kitchen 1949 United States Department of Agriculture (USDA) Color
 
13:31
more at http://kitchen.quickfound.net The USDA describes and demonstrates the results of their efforts to develop a modern "step-saving" kitchen. NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=RF3JAY8Gyz4 Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Kitchen A kitchen is a room or part of a room used for cooking and food preparation. In the West, a modern residential kitchen is typically equipped with a stove, a sink with hot and cold running water, a refrigerator and kitchen cabinets arranged according to a modular design. Many households have a microwave oven, a dishwasher and other electric appliances. The main function of a kitchen is cooking or preparing food but it may also be used for dining, food storage, entertaining, dishwashing and laundry... History The evolution of the kitchen is linked to the invention of the cooking range or stove and the development of water infrastructure capable of supplying water to private homes. Until the 18th century, food was cooked over an open fire. Technical advances in heating food in the 18th and 19th centuries, changed the architecture of the kitchen. Before the advent of modern pipes, water was brought from an outdoor source such as wells, pumps or springs. Antiquity The houses in Ancient Greece were commonly of the atrium-type: the rooms were arranged around a central courtyard for women. In many such homes, a covered but otherwise open patio served as the kitchen. Homes of the wealthy had the kitchen as a separate room... In the Roman Empire, common folk in cities often had no kitchen of their own; they did their cooking in large public kitchens. Some had small mobile bronze stoves, on which a fire could be lit for cooking. Wealthy Romans had relatively well-equipped kitchens... Middle Ages Early medieval European longhouses had an open fire under the highest point of the building. The "kitchen area" was between the entrance and the fireplace. In wealthy homes there was typically more than one kitchen... In the larger homesteads of European nobles, the kitchen was sometimes in a separate sunken floor building to keep the main building, which served social and official purposes, free from indoor smoke. The first known stoves in Japan date from about the same time. The earliest findings are from the Kofun period (3rd to 6th century). These stoves, called kamado, were typically made of clay and mortar; they were fired with wood or charcoal through a hole in the front and had a hole in the top, into which a pot could be hanged by its rim. This type of stove remained in use for centuries to come... Colonial America... Technological advances during industrialization brought major changes to the kitchen. Iron stoves, which enclosed the fire completely and were more efficient, appeared. Early models included the Franklin stove around 1740, which was a furnace stove intended for heating, not for cooking. Benjamin Thompson in England designed his "Rumford stove" around 1800. This stove was much more energy efficient than earlier stoves; it used one fire to heat several pots, which were hung into holes on top of the stove and were thus heated from all sides instead of just from the bottom. However, his stove was designed for large kitchens; it was too big for domestic use. The "Oberlin stove" was a refinement of the technique that resulted in a size reduction; it was patented in the U.S. in 1834 and became a commercial success with some 90,000 units sold over the next 30 years. These stoves were still fired with wood or coal. Although the first gas street lamps were installed in Paris, London, and Berlin at the beginning of the 1820s and the first U.S. patent on a gas stove was granted in 1825, it was not until the late 19th century that using gas for lighting and cooking became commonplace in urban areas... The Hoosier Manufacturing Co. of Indiana adapted an existing furniture piece, the baker's cabinet, which had a similar structure of a table top with some cabinets above it (and frequently flour bins beneath) to solve the storage problem. By rearranging the parts and taking advantage of (then) modern metal working, they were able to produce a well-organized, compact cabinet which answered the home cook's needs for storage and working space. A distinctive feature of the Hoosier cabinet is its accessories. As originally supplied, they were equipped with various racks and other hardware to hold and organize spices and various staples...
Просмотров: 301120 Jeff Quitney
Car Transmissions & Synchromesh: "Spinning Levers" 1936 Chevrolet Auto Mechanics 10min
 
09:40
more at http://auto-parts.quickfound.net/ Auto mechanics playlist: http://www.youtube.com/playlist?list=PLCED11EACAE477F6C '"The transmission in the modern motorcar -- the mechanism that makes it possible to have three forward speeds and a reverse -- is a series of levers, levers that spin." VS cartoon of Archimedes trying to move earth with a lever extending from the moon or another planet in outer space; CU cartoon of Archimedes says "Give me a lever long enough and I can move the world." CU disembodied hands using antique can opener to open a can of peaches; CU can open cutting through top of can. Two boys playing on a seesaw. CU pitch bar tool inserted between train wheel and track; man cranks large lever to move freight car along track; CU disembodied arm pumps lever lifting antique car off ground. VS man demonstrates basics of the lever using triangular piece as fulcrum and a long metal piece, man attaches 10 lbs. weight to one end of the bar and a 5 lbs. weight to the other end; man hangs various weights from both ends of the bar balancing the two by moving the fulcrum to various points along the bar; man demonstrates how a gear is constructed through numerous interlocking levers. VS stop-motion animation of two wheels with paddles added one by one turning wheels into paddle wheels and then into interlocking gears; cuts to more sophisticated gear; cuts to metal gears; VS CU different types of machine gears, worm gears, bevel gears, lopsided gears. Disembodied arm pieces together piece by piece a basic motor with various gear components; superimposed text appears labeling various parts; superimposed arrows identify different gears; motor begins to turn; cuts to CU car drives across frame; cuts back to crude motor; camera pans to Revolutions Per Minute dial which reads 100 rpm, camera pans to another RPM instrument dial which reads 30 rpm; CU crude model of gears in motor, superimposed arrows show flow of energy through the system. CU RPM instrument dial reads 60 rpm; CU churning gears of motor, superimposed arrows she flow of energy through gear system; VS man demonstrates on gears how shifting to various gears works. CU arrow point to 90 rpm on deal labeled Revolutions Per Minute; VS man demonstrating different gears. Great shot 4 lanes of cars stopped at stoplight on city street; Travel Bureau sign in background. CU disembodied hand in white glove shifts clutch of car; CU motor shifting gears; CU tire with Chevrolet hubcap begins to move; 1920s and 1930s cars stopped at traffic light begin to move; CU inside car woman shifts gears; car driving down tree-lined highway in possibly New York, what appears to be the Statue of Liberty is seen off in the distance. Woman enters drivers seat of Chevrolet, man waves start flag; car drives off down street; CU disembodied woman's foot on gas pedal beside break and clutch pedal with Chevrolet logos; CU speedometer shows car hitting 60 mph; CU woman downshifts; CU speedometer goes down to 35 mph; car stops at bottom of hill. CU sign along rugged road 'Steep Hill Use Second Gear"' NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=69TC-GLnfDQ Public domain film from the Library of Congress Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Transmission_(mechanics) A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a live axle. Often transmission refers simply to the gearbox that uses gears and gear trains to provide speed and torque conversions from a rotating power source to another device... Manual Manual transmission come in two basic types: - a simple but rugged sliding-mesh or unsynchronized / non-synchronous system, where straight-cut spur gear sets are spinning freely, and must be synchronized by the operator matching engine revs to road speed, to avoid noisy and damaging "gear clash", - and the now common constant-mesh gearboxes which can include non-synchronised, or synchronized / synchromesh systems, where typically diagonal cut helical (or sometimes either straight-cut, or double-helical) gear sets are constantly "meshed" together, and a dog clutch is used for changing gears. On synchromesh boxes, friction cones or "synchro-rings" are used in addition to the dog clutch to closely match the rotational speeds of the two sides of the (declutched) transmission before making a full mechanical engagement...
Просмотров: 1554799 Jeff Quitney
Latrine Procedures "Use Your Head" 1945 US Navy USMC Training Film World War II 5min
 
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more at http://quickfound.net/links/military_news_and_links.html "U.S. Navy animated training film by Hugh Harman Productions. Features the character Private McGillicuddy. Used to train U.S. Marines about dysentery & safe latrine practices." US Navy Training Film MN-2808g (for the US Marine Corps) NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=YltpO-7DKKw Originally a public domain film slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Latrine Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ A latrine is a communal facility containing one or more (commonly many) toilets which may be simple pit toilets or in the case of the United States Armed Forces (or more specifically, the US Army and US air force) any toilet including modern flush toilets. The term is derived from the Latin lavatrina meaning bath. Many forms of latrine technology have been used in the past, from utterly simple to more sophisticated, while newer developments show promise using ecological sanitation (EcoSan). Pit toilets are the simplest and cheapest type, minimally defined as a hole in the ground. More sophisticated pit toilets may include a floor plate, a waterproof liner for the pit to avoid contamination of the water table or ventilation to reduce odor and fly/mosquito breeding. Other technologies may be used including Reed Odourless Earth Closet (ROEC) or Composting toilets, Pour-Flush Latrine, popularized by Sulabh International, Cistern-Flush Toilet, Bucket Latrine or Pour-Flush Toilet and Vault.[citation needed] The term "Flying Latrine" has been used to describe an unsanitary practice in some urban slums in Africa. With no running water or sewer systems, a person may resort to using a plastic bag as a container for excrement, then throw or sling the bag as far away as possible. This practice has led to the banning of the manufacture and import of such bags in Uganda, Kenya, and Tanzania. In locations with no functioning toilets latrines or trench toilets are typically set up for use by groups of men and/or women. They typically consists of pits or trenches, 4 feet (1.2 m) to 5 feet (1.5 m) deep and 4 feet (1.2 m) to 20 feet (6.1 m) long, dug into the ground. Many Army units, if they stayed in one location long, had primitive shelters and seating arrangements arranged over the pits. The pits are typically kept well away from any water sources to minimize possible disease transmission. After extended use the pits were typically filled in. In the Army each company typically had two soldiers assigned as sanitary personnel (usually personnel who had broken the rules) whose job it was to keep the latrines in good condition. Each Army unit was supposed to fill in its latrines and dig a new one for new arrivals. The use of latrines were a major advance in sanitation over more primitive "every man for himself" sanitation practices and helped control the spread of many diseases. Up to about 1920, when better sanitation practices were adopted, many more soldiers died of disease than from wounds... http://en.wikipedia.org/wiki/Pit_toilet A pit toilet is a dry toilet system which collects human excrement in a large container and range from a simple slit trench to more elaborate systems with ventilation. They are more often used in rural and wilderness areas as well as in much of the developing world. The waste pit, in some cases, will be large enough that the reduction in mass of the contained waste products by the ongoing process of decomposition allows the pit to be more or less permanent. In other cases, when the pit becomes too full, it may be emptied or the hole made be covered with soil and the associated structure moved or rebuilt over a new pit. The pit toilet shares some characteristics with a composting toilet, but the latter combines the waste with sawdust, coconut coir, peat moss or similar to support aerobic processing in a more controlled manner...
Просмотров: 115882 Jeff Quitney
Eisenhower Presidential Campaign Commercial "I Like Ike" 1952 Roy Disney Cartoon
 
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more at http://quickfound.net 'The "I Like Ike" animated television commercial, produced by Roy Disney and Citizens for Eisenhower-Nixon.' NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=6sk_snD8yrQ Originally a public domain film from the Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/United_States_presidential_election,_1952 Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ The United States presidential election of 1952 was the 42nd quadrennial presidential election, held on Tuesday, November 4, 1952. Republican Dwight Eisenhower was the landslide winner, ending a string of Democratic wins that stretched back to 1932. He carried the Republican Party (GOP) to narrow control of the House and Senate. During this time, Cold War tension between the United States and the Soviet Union was at a high level. Foreign policy was a main issue in the race for the Republican nomination. The nation was polarized over the stalemated Korean War, and the extent of corruption in the federal government became a major issue as well. The economy was prosperous, and economic and social issues played little role. Unpopular incumbent President Harry S. Truman decided not to run after a poor primary showing. The Democratic Party instead nominated Governor Adlai Stevenson of Illinois. Stevenson had gained a reputation in Illinois as an intellectual and eloquent orator. The Republican Party saw a contest between the internationalist and isolationist perspectives. Eisenhower the NATO commander and war hero defeated Senator Robert A. Taft, the isolationist, for the nomination and crusaded against "Korea, Communism and Corruption." Ike, as they called him, did well in all major demographic and regional groups except the Deep South. Eisenhower, at 62, was the oldest man to become president since James Buchanan in 1856... The Eisenhower campaign was one of the first presidential campaigns to make a major, concerted effort to win the female vote. Many of his radio and television commercials discussed topics such as education, inflation, ending the war in Korea, and other issues that were thought to appeal to women. The Eisenhower campaign made extensive use of female campaign workers. These workers made phone calls to likely Eisenhower voters, distributed "Ike" buttons and leaflets, and gave parties to build support for the GOP ticket in their neighborhoods. On election day Eisenhower won a solid majority of the female vote. Eisenhower campaigned by attacking "Korea, Communism, and Corruption..." Eisenhower retained his enormous personal popularity from his leading role in World War II, and huge crowds turned out to see him around the nation. His campaign slogan, "I Like Ike," was one of the most popular in American history. Stevenson concentrated on giving a series of thoughtful speeches around the nation; he too drew large crowds. Although his style thrilled intellectuals and academics, some political experts wondered if he were speaking "over the heads" of most of his listeners, and they dubbed him an "egghead," based on his baldness and intellectual demeanor. Eisenhower maintained a comfortable lead in the polls throughout most of the campaign...
Просмотров: 39587 Jeff Quitney
Stunt Driving 1966 Chevys by Joie Chitwood Thrill Show Hell Drivers, from "Impact '66"
 
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more at http://cars.quickfound.net/ At the GM proving grounds, Milford, Michigan, Joie Chitwood Thrill Show "Hell Drivers" (and GM test drivers) perform speed runs and stunts in 1966 Chevrolets. From "Impact '66", a marketing film for Chevy salesmen. Public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Joie_Chitwood George Rice "Joie" Chitwood (April 14, 1912 - January 3, 1988) was an American racecar driver and businessman. He is best known as a daredevil in the Joie Chitwood Thrill Show. Born in Denison, Texas of Cherokee Indian ancestry, he was dubbed "Joie" by a track promoter and the name stuck. Racing career Chitwood started his racecar driving career in 1934 at a dirt track in Winfield, Kansas. From there, he began racing sprint cars. In 1939 and 1940 he won the AAA East Coast Sprint car championship. He switched to the CSRA and won its title in 1942. Between 1940 and 1950 competed at the Indianapolis 500 seven times finishing fifth on three different occasions. He was the first man ever to wear a safety belt at the Indy 500. Joie Chitwood Thrill Show Chitwood also operated the "Joie Chitwood Thrill Show", an exhibition of auto stunt driving that became so successful he gave up racing. Often called "Hell Drivers," he had five units that for more than forty years toured across North America thrilling audiences in large and small towns alike with their death-defying automobile stunts. His show was so popular, that in January 1967, the performance at the Islip Speedway, New York was broadcast on ABC television's Wide World of Sports. On May 13, 1978, Joie Chitwood set a world record when he drove a Chevrolet Chevette for 5.6 miles (9.0 km) on just 2 wheels. His sons, Joie Jr. and Tim both joined the auto thrill show and continued to run the "Joie Chitwood Chevy Thunder Show" after their father's retirement. His grandson, Joie Chitwood III, is the President of Daytona International Speedway and a former president of the Indianapolis Motor Speedway. The show was featured during season 3 of CHiPs in an episode entitled "Thrill Show". Chitwood's show was credited by Evel Knievel as being his inspiration to become a daredevil. Stuntman Chitwood was frequently hired by Hollywood film studios to either do stunt driving for films or to act as auto-stunt coordinator. On a few occasions he appeared in a minor role, notably with Clark Gable and Barbara Stanwyck in the 1950 film about auto racing, To Please a Lady. In 1973, Chitwood is credited as a Stunt Coordinator for the hugely successful James Bond film Live and Let Die (film), where he was also the stunt driver and acted in a minor part. Safety Consultant Chitwood also acted as a car safety consultant, intentionally crashing vehicles for subsequent investigation. He had intentionally crashed more than 3000 vehicles by the time he appeared on the game show I've Got A Secret in 1965. Retirement When Chitwood retired, his sons took over the business. Joie Chitwood died in 1988, aged 75, in Tampa Bay, Florida. He was inducted in the National Sprint Car Hall of Fame in 1993. He was inducted in the Motorsports Hall of Fame of America in 2010 in the Historic category.
Просмотров: 31931 Jeff Quitney
Principles of Refrigeration 1963 US Air Force
 
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NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=Ziel0Dj_blk more at http://scitech.quickfound.net/ "SHOWS APPLICATION OF BASIC PHYSICS OF HEAT TRANSFER IN REFRIGERATION UNITS. EXPLAINS TEMPERATURE CHANGES IN REFRIGERANT PASSING THROUGH THE EXPANSION VALVE, COMPRESSOR, CONDENSER AND EVAPORATOR AS IT CARRIES HEAT TO THE OUTSIDE AIR." Public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization. US Air Force training film TF-5536a http://en.wikipedia.org/wiki/Refrigeration Refrigeration is a process in which work is done to move heat from one location to another. This work is traditionally done by mechanical work, but can also be done by magnetism, laser or other means. Refrigeration has many applications, including, but not limited to: household refrigerators, industrial freezers, cryogenics, air conditioning, and heat pumps... First refrigeration systems The first known method of artificial refrigeration was demonstrated by William Cullen at the University of Glasgow in Scotland in 1756. Cullen used a pump to create a partial vacuum over a container of diethyl ether, which then boiled, absorbing heat from the surrounding air.[4] The experiment even created a small amount of ice, but had no practical application at that time. In 1758, Benjamin Franklin and John Hadley, professor of chemistry at Cambridge University, conducted an experiment to explore the principle of evaporation as a means to rapidly cool an object. Franklin and Hadley confirmed evaporation of highly volatile liquids, such as alcohol and ether, could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to "quicken" the evaporation; they lowered the temperature of the thermometer bulb down to 7 °F (−14 °C), while the ambient temperature was 65 °F (18 °C). Franklin noted that soon after they passed the freezing point of water (32 °F), a thin film of ice formed on the surface of the thermometer's bulb and that the ice mass was about a quarter inch thick when they stopped the experiment upon reaching 7 °F (−14 °C). Franklin concluded, "From this experiment, one may see the possibility of freezing a man to death on a warm summer's day". In 1805, American inventor Oliver Evans designed, but never built, a refrigeration system based on the vapor-compression refrigeration cycle rather than chemical solutions or volatile liquids such as ethyl ether. In 1820, the British scientist Michael Faraday liquefied ammonia and other gases by using high pressures and low temperatures. An American living in Great Britain, Jacob Perkins, obtained the first patent for a vapor-compression refrigeration system in 1834. Perkins built a prototype system and it actually worked, although it did not succeed commercially. In 1842, an American physician, John Gorrie, designed the first system to refrigerate water to produce ice. He also conceived the idea of using his refrigeration system to cool the air for comfort in homes and hospitals (i.e., air conditioning). His system compressed air, then partly cooled the hot compressed air with water before allowing it to expand while doing part of the work needed to drive the air compressor. That isentropic expansion cooled the air to a temperature low enough to freeze water and produce ice, or to flow "through a pipe for effecting refrigeration otherwise" as stated in his patent granted by the U.S. Patent Office in 1851. Gorrie built a working prototype, but his system was a commercial failure. Alexander Twining began experimenting with vapor-compression refrigeration in 1848, and obtained patents in 1850 and 1853. He is credited with having initiated commercial refrigeration in the United States by 1856... Domestic mechanical refrigerators became available in the United States around 1911... Cyclic refrigeration This consists of a refrigeration cycle, where heat is removed from a low-temperature space or source and rejected to a high-temperature sink with the help of external work, and its inverse, the thermodynamic power cycle. In the power cycle, heat is supplied from a high-temperature source to the engine, part of the heat being used to produce work and the rest being rejected to a low-temperature sink. This satisfies the second law of thermodynamics. A refrigeration cycle describes the changes that take place in the refrigerant as it alternately absorbs and rejects heat as it circulates through a refrigerator. It is also applied to HVACR work, when describing the "process" of refrigerant flow through an HVACR unit, whether it is a packaged or split system...
Просмотров: 103231 Jeff Quitney
Death Valley 20 Mule Team Replaced by Trucks 1939 Chevrolet Newsreel
 
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more at http://quickfound.net Re-enactment of the last run of the 20 Mule Team that ferried borax out of Death Valley (from 1883 to 1889) to Mojave. Shows the job is now done by Chevy trucks. 'Title Card: "Scorched!, Lose Death Valley Run, Last Haul for Mules" Mule team and truck hauling borax through desert. LS barren desert with low maintain range. VS mule team plodding through desert pulling wagon train. Dump truck with dust blowing from load of borax in bed; truck pulls away. VS truck driving through various rough terrain, desert, across stream, over sandy bank, up steep hill. Dump truck arriving at industrial facility.' From Chevrolet Leader News Newsreel Vol. 5 No. 1. Public domain film from the Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Twenty-mule_team Twenty-mule teams were teams of eighteen mules and two horses attached to large wagons that ferried borax out of Death Valley from 1883 to 1889. They traveled from mines across the Mojave Desert to the nearest railroad spur, 165 miles (275 km) away in Mojave, California. The routes were from Furnace Creek, California, to Mojave, California, and from the mines at Old Borate to Mojave. The wagons were among the largest ever pulled by draft animals, designed to carry 10 short tons (9 metric tons) of borax ore at a time... In 1877, six years before twenty-mule teams had been introduced into Death Valley, Scientific American reported that Francis Marion Smith and his brother had shipped their company's borax in a 30-ton load using two large wagons, with a third wagon for food and water, drawn by a 24-mule team over a 160-mile stretch of desert between Teel's Marsh and Wadsworth, Nevada. The twenty-mule-team wagons were designed to carry 10 short tons (9 metric tons) of borax ore at a time. The rear wheels measured seven feet (2.1 m) high, with tires made of one-inch-thick (25 mm) iron. The wagon beds measured 16 feet long and were 6 feet deep (4.9 m long, 1.8 m deep); constructed of solid oak, they weighed 7,800 pounds (3,500 kg) empty; when loaded with ore, the total weight of the mule train was 73,200 pounds (33.2 metric tons or 36.6 short tons). The first wagon was the trailer, the second was "the tender" or the "back action", and the tank wagon brought up the rear... http://en.wikipedia.org/wiki/Pacific_Coast_Borax_Company The Pacific Coast Borax Company (PCB) was a United States mining company founded in 1890 by the American borax magnate Francis "Borax" Smith, the "Borax King"... The company established and aggressively developed and marketed the 20 Mule Team Borax trademark in order to promote the sale of its product. The name derived from the Twenty Mule teams that were used to transport borax out of Death Valley in the 1880s from Harmony Borax Works near Furnace Creek Ranch owned by William Tell Coleman at that time and sold to Smith in 1890. They also produced Boraxo hand soap. The popular radio and TV series Death Valley Days was hosted by "Borateem-pitchman" and future president Ronald Reagan... http://en.wikipedia.org/wiki/Borax Borax, also known as sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid. Powdered borax is white, consisting of soft colorless crystals that dissolve easily in water. Borax has a wide variety of uses. It is a component of many detergents, cosmetics, and enamel glazes. It is also used to make buffer solutions in biochemistry, as a fire retardant, as an anti-fungal compound for fiberglass, as a flux in metallurgy, neutron-capture shields for radioactive sources, a texturing agent in cooking, and as a precursor for other boron compounds... Borax was first discovered in dry lake beds in Tibet and was imported via the Silk Road to Arabia... http://en.wikipedia.org/wiki/Death_Valley Death Valley is a desert valley located in Eastern California. Situated within the Mojave Desert, it is the lowest and driest area in North America, and currently the hottest in the world...
Просмотров: 53071 Jeff Quitney
Cray-2 Supercomputer: "World's Most Powerful Computer" 1986 NASA Ames Research Center
 
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more at http://computers.quickfound.net/ "The use of the Cray 2 supercomputer, the fastest computer in the world, at ARC is detailed. The Cray 2 can perform 250 million calculations per second and has 10 times the memory of any other computer. Ames researchers are shown creating computer simulations of aircraft airflow, waterflow around a submarine, and fuel flow inside of the Space Shuttle's engines. The video also details the Cray 2's use in calculating airflow around the Shuttle and its external rockets during liftoff for the first time and in the development of the National Aero Space Plane." Public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization. http://en.wikipedia.org/wiki/Cray-2 The Cray-2 was a four-processor ECL vector supercomputer made by Cray Research starting in 1985. It was the fastest machine in the world when it was released, replacing the Cray Research X-MP designed by Steve Chen in that spot. The Cray-2 was capable of 1.9 GFLOPS peak performance and was only bumped off of the top spot by the ETA-10G in 1990... With the successful launch of his famed Cray-1, Seymour Cray turned to the design of its successor. By 1979 he had become fed up with management interruptions in what was now a large company, and as he had done in the past, decided to resign his management post and move to form a new lab. As with his original move to Chippewa Falls, Wisconsin from Control Data HQ in Minneapolis, MN, Cray management understood his needs and supported his move to a new lab in Boulder, Colorado. Working as an independent consultant at these new Cray Labs, he put together a team and started on a completely new design... Cray had previously attacked the problem of increased speed with three simultaneous advances: more functional units to give the system higher parallelism, tighter packaging to decrease signal delays, and faster components to allow for a higher clock speed. The classic example of this design is the CDC 8600, which packed four CDC 7600-like machines based on ECL logic into a 1 x 1 meter cylinder and ran them at an 8 ns cycle speed (125 MHz). Unfortunately the density needed to achieve this cycle time led to the machine's downfall. The circuit boards inside were densely packed, and since even a single malfunctioning transistor would cause an entire module to fail, packing more of them onto the cards greatly increased the chance of failure. One solution to this problem, one that most computer vendors had already moved to, was to use integrated circuits (ICs) instead of individual components. Each IC included a selection of components from a module pre-wired into a circuit by the automated construction process. If an IC did not work, another one would be tried. At the time the 8600 was being designed the simple MOSFET-based technology did not offer the speed Cray needed. Relentless improvements changed things by the mid-1970s, however, and the Cray-1 had been able to use newer ICs and still run at a respectable 12.5 ns (80 MHz). In fact, the Cray-1 was actually somewhat faster than the 8600 because it packed considerably more logic into the system due to the IC's small size. Although IC design continued to improve, the physical size of the ICs was constrained largely by mechanical limits; the resulting component had to be large enough to solder into a system.... Cray-2 models soon settled on a design using large circuit boards packed with ICs. This made them extremely difficult to solder together, and the density was still not enough to reach their performance goals... Six months later Cray had his "eureka" moment. He called the main engineers together for a meeting and presented a new solution to the problem. Instead of making one larger circuit board, each "card" would instead consist of a 3-D stack of eight, connected together in the middle of the boards using pins sticking up from the surface (known as "pogos" or "z-pins"). The cards were packed right on top of each other, so the resulting stack was only about 3 inches high... there was too little room for air to flow between the ICs. Instead the system would be immersed in a tank of a new inert liquid from 3M, Fluorinert... Due to the use of liquid cooling, the Cray-2 was given the nickname "Bubbles", and common jokes around the computer made reference to this unique system. Gags included "No Fishing" signs, cardboard depictions of the Loch Ness Monster rising out of the heat exchanger tank, plastic fish inside the exchanger, etc. The power of the Cray-2 was 150 - 200 kW. Each vertical stack of logic modules sat above a stack of power modules which powered 5 volt bus bars, each of which delivered about 2200 amps. The Cray-2 was powered by two motor-generators, which took in 480 V three-phase.
Просмотров: 104363 Jeff Quitney
How Magnets Produce Electricity 1954 US Navy Electromagnetism Primer
 
03:48
more at http://scitech.quickfound.net/ "HOW A MAGNETIC FIELD EFFECTS A SINGLE ATOM, A GROUP OF ATOMS AND A WIRE IN A CLOSED CIRCUIT WITH A METER." NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=2TbdXRe-Qyw Public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization. US Navy training film MN-8016b http://en.wikipedia.org/wiki/Electric_generator ...Before the connection between magnetism and electricity was discovered, electrostatic generators were invented that used electrostatic principles. These generated very high voltages and low currents. They operated by using moving electrically charged belts, plates and disks to carry charge to a high potential electrode... In 1827, Hungarian Anyos Jedlik started experimenting with electromagnetic rotating devices which he called electromagnetic self-rotors. In the prototype of the single-pole electric starter (finished between 1852 and 1854) both the stationary and the revolving parts were electromagnetic. He formulated the concept of the dynamo at least 6 years before Siemens and Wheatstone but didn't patent it as he thought he wasn't the first to realize this. In essence the concept is that instead of permanent magnets, two electromagnets opposite to each other induce the magnetic field around the rotor. It was also the discovery of the principle of self-excitation... In the years of 1831--1832, Michael Faraday discovered the operating principle of electromagnetic generators. The principle, later called Faraday's law, is that an electromotive force is generated in an electrical conductor that encircles a varying magnetic flux. He also built the first electromagnetic generator, called the Faraday disk, a type of homopolar generator, using a copper disc rotating between the poles of a horseshoe magnet. It produced a small DC voltage. This design was inefficient due to self-cancelling counterflows of current in regions not under the influence of the magnetic field... The dynamo was the first electrical generator capable of delivering power for industry. The dynamo uses electromagnetic principles to convert mechanical rotation into pulsed DC through the use of a commutator. The first dynamo was built by Hippolyte Pixii in 1832. Through a series of accidental discoveries, the dynamo became the source of many later inventions, including the DC electric motor, the AC alternator, the AC synchronous motor, and the rotary converter. A dynamo machine consists of a stationary structure, which provides a constant magnetic field, and a set of rotating windings which turn within that field. On small machines the constant magnetic field may be provided by one or more permanent magnets; larger machines have the constant magnetic field provided by one or more electromagnets, which are usually called field coils. Large power generation dynamos are now rarely seen due to the now nearly universal use of alternating current for power distribution and solid state electronic AC to DC power conversion. But before the principles of AC were discovered, very large direct-current dynamos were the only means of power generation and distribution. Now power generation dynamos are mostly a curiosity... Without a commutator, a dynamo becomes an alternator, which is a synchronous singly fed generator. When used to feed an electric power grid, an alternator must always operate at a constant speed that is precisely synchronized to the electrical frequency of the power grid. A DC generator can operate at any speed within mechanical limits, but always outputs direct current...
Просмотров: 97387 Jeff Quitney
Space Station Centrifuge Gravity Simulation 196x NASA color 3min
 
02:38
video for embedding at http://scitech.quickfound.net/ Space station artificial gravity is tested in a centrifuge of the type seen in "2001: A Space Odyssey" at NASA Langley Research Center. Two different rotation rates simulate one-tenth gravity (0.1 G, station rotating at about 4 rpm) and one-half gravity (0.5 G, station rotating at about 9 rpm). This is the same public domain video uploaded by NASA with letterboxing (black borders) removed and the aspect ratio corrected. Also, this particular NASA Langley video contained two other unrelated segments (comparison of walking and running Earth and lunar gravity, and lunar landing simulation in simulated lunar gravity) which I have uploaded separately. NASA, space program, astronaut, artificial gravity, centrifuge, simulation, Langley Research Center, space station
Просмотров: 88209 Jeff Quitney
Private SNAFU "The Home Front" 1943 US Army Cartoon Mel Blanc, Frank Tashlin, World War II
 
04:25
more at http://quickfound.net/links/military_news_and_links.html "Private Snafu imagines the good times his family is having back home while he's stationed in the Arctic. Technical Fairy First Class shows that even his family is helping with the war effort - his dad building tanks, his mom planting a Victory Garden, Grandpa riveting battleships, and his girl joining the WAC's and even the family's horse is pitching in. This is one of 26 Private SNAFU ('Situation Normal, All Fouled Up) cartoons made by the US Army Signal Corps to educate and boost the morale the troops. Originally created by Theodore Geisel (Dr. Seuss) and Phil Eastman, most of the cartoons were produced by Warner Brothers Animation Studios - employing their animators, voice actors (primarily Mel Blanc) and Carl Stalling's music." Public domain film slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Private_Snafu Private Snafu is the title character of a series of black-and-white American instructional cartoon shorts produced between 1943 and 1945 during World War II. The character was created by director Frank Capra, chairman of the U.S. Army Air Force First Motion Picture Unit, and most were written by Theodor "Dr. Seuss" Geisel, Philip D. Eastman, and Munro Leaf. Although the United States Army gave Walt Disney the first crack at creating the cartoons, Leon Schlesinger of the Warner Bros. animation studio underbid Disney by two-thirds and won the contract. Disney had also demanded exclusive ownership of the character, and merchandising rights. Nel (2007) shows the goal was to help enlisted men with weak literacy skills learn through animated cartoons (and also supplementary comic books). They featured simple language, racy illustrations, no profanity, and subtle moralizing. Private Snafu did everything wrong, so that his negative example taught basic lessons about secrecy, disease prevention, and proper military protocols. Private Snafu cartoons were a military secret—for the armed forces only. Surveys to ascertain the soldiers' film favorites showed that the Snafu cartoons usually rated highest or second highest. Each cartoon was produced in six weeks, compared to the six months usually taken for short cartoons of the same kind... Most of the Private Snafu shorts are educational, and although the War Department had to approve the storyboards, the Warner directors were allowed great latitude in order to keep the cartoons entertaining... The Snafu shorts are notable because they were produced during the Golden Age of Warner Bros. animation. Directors such as Chuck Jones, Friz Freleng, Bob Clampett, and Frank Tashlin worked on them, and their characteristic styles are in top form. P. D. Eastman was a writer and storyboard artist for the Snafu shorts. Voice characterizations were provided by the celebrated Mel Blanc (Private Snafu's voice was similar to Blanc's Bugs Bunny characterization, and Bugs himself actually made cameos in the Snafu episodes Gas and Three Brothers). Toward the end of the war, other studios began producing Snafu shorts as well (the Army accused Schlesinger of padding his bills), though some of these never made it to celluloid before the war ended. The Snafu films are also partly responsible for keeping the animation studios open during the war—by producing such training films, the studios were declared an essential industry. After the war, the Snafu cartoons went largely forgotten. Prints eventually wound up in the hands of collectors, and these form the basis for The Complete, Uncensored Private Snafu, a VHS and DVD collection from Bosko Video...
Просмотров: 1540893 Jeff Quitney
Auto Mechanics: Brakes: "Facts on Friction" 1934 General Motors
 
09:30
NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=cJTmx_cxS30 more at http://auto-parts.quickfound.net/ Public domain film from the Library of Congress Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Drum_brake A drum brake is a brake in which the friction is caused by a set of shoes or pads that press against a rotating drum-shaped part called a brake drum. The term "drum brake" usually means a brake in which shoes press on the inner surface of the drum. When shoes press on the outside of the drum, it is usually called a clasp brake. Where the drum is pinched between two shoes, similar to a conventional disk brake, it is sometimes called a "pinch drum brake", although such brakes are relatively rare. A related type of brake uses a flexible belt or "band" wrapping around the outside of a drum, called a band brake. History The modern automobile drum brake was invented in 1902 by Louis Renault, though a less-sophisticated drum brake had been used by Maybach a year earlier. In the first drum brakes, the shoes were mechanically operated with levers and rods or cables. From the mid-1930s the shoes were operated with oil pressure in a small wheel cylinder and pistons (as in the picture), though some vehicles continued with purely-mechanical systems for decades. Some designs have two wheel cylinders. The shoes in drum brakes are subject to wear and the brakes needed to be adjusted regularly until the introduction of self-adjusting drum brakes in the 1950s. In the 1960s and 1970s brake drums on the front wheels of cars were gradually replaced with disc brakes and now practically all cars use disc brakes on the front wheels, with many offering disc brakes on all wheels. However, drum brakes are still often used for handbrakes as it has proven very difficult to design a disc brake suitable for holding a car when it is not in use. Moreover, it is very easy to fit a drum handbrake inside a disc brake so that one unit serves as both service brake and handbrake. Early type brake shoes contained asbestos. When working on brake systems of older cars, care must be taken not to inhale any dust present in the brake assembly. The United States Federal Government began to regulate asbestos production, and brake manufacturers had to switch to non-asbestos linings. Owners initially complained of poor braking with the replacements; however, technology eventually advanced to compensate. A majority of daily-driven older vehicles have been fitted with asbestos-free linings. Many other countries also limit the use of asbestos in brakes. Some of the major components of the drum brake assembly are the back plate, the brake drum and shoe, the wheel cylinder, and various springs and pins. Back plate The back plate serves as the base on which all the components are assembled. It attaches to the axle and forms a solid surface for the wheel cylinder, brake shoes and assorted hardware. Since all the braking operations exert pressure on the back plate, it needs to be very strong and wear-resistant. Levers for emergency or parking brakes, and automatic brake-shoe adjuster were also added in recent years. Brake drum The brake drum is generally made of a special type of cast iron which is heat-conductive and wear-resistant. It is positioned very close to the brake shoe without actually touching it, and rotates with the wheel and axle... Wheel cylinder One wheel cylinder is used for each wheel. Two pistons operate the shoes, one at each end of the wheel cylinder. When hydraulic pressure from the master cylinder acts upon the piston cup, the pistons are pushed toward the shoes, forcing them against the drum. When the brakes are not being applied, the piston is returned to its original position by the force of the brake shoe return springs... Brake shoe Brake shoes are typically made of two pieces of sheet steel welded together. The friction material is either rivetted to the lining table or attached with adhesive. The crescent-shaped piece is called the Web and contains holes and slots in different shapes for return springs, hold-down hardware, parking brake linkage and self-adjusting components. All the application force of the wheel cylinder is applied through the web to the lining table and brake lining. The edge of the lining table generally has three "V"-shaped notches or tabs on each side called nibs. The nibs rest against the support pads of the backing plate to which the shoes are installed...
Просмотров: 181630 Jeff Quitney
Nuclear Reactor Meltdown: "SL-1 Accident Briefing Film Report" 1961 AEC Atomic Energy Commission
 
08:39
more at http://scitech.quickfound.net US Army experimental nuclear power reactor SL-1 underwent a steam explosion and meltdown on January 3, 1961, killing its three operators. This film re-enacts how the accident may have occurred. NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=Mtfi-cNFRgU Film explaining what was done after the accident was discovered: https://www.youtube.com/watch?v=otxLfg0apRs Public domain film from the Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/SL-1 The SL-1, or Stationary Low-Power Reactor Number One, was a United States Army experimental nuclear power reactor which underwent a steam explosion and meltdown on January 3, 1961, killing its three operators. The direct cause was the improper withdrawal of the central control rod, responsible for absorbing neutrons in the reactor core. The event is the only known fatal reactor incident in the United States. The incident released about 80 curies (3.0 TBq) of iodine-131, which was not considered significant due to its location in a remote desert of Idaho. About 1,100 curies (41 TBq) of fission products were released into the atmosphere. The facility, located at the National Reactor Testing Station (NRTS) approximately 40 miles (64 km) west of Idaho Falls, Idaho, was part of the Army Nuclear Power Program and was known as the Argonne Low Power Reactor (ALPR) during its design and build phase. It was intended to provide electrical power and heat for small, remote military facilities, such as radar sites near the Arctic Circle, and those in the DEW Line. The design power was 3 MW (thermal). Operating power was 200 kW electrical and 400 kW thermal for space heating. In the incident the core power level reached nearly 20 GW in just four milliseconds, precipitating the steam explosion... From 1954 to 1955, the U.S. Army evaluated their need for nuclear reactor plants that would be operable in remote regions of the Arctic. [The Army] contracted with Argonne National Laboratory to design, build, and test a prototype reactor plant to be called the Argonne Low Power Reactor (ALPR)... Incident and response On December 21, 1960, the reactor was shut down for maintenance... and installation of 44 flux wires to monitor the neutron flux levels in the reactor core. The wires were made of aluminum, and contained slugs of aluminum--cobalt alloy. On January 3, 1961, the reactor was being prepared for restart after a shutdown of eleven days over the holidays. Maintenance procedures were in progress, which required the main central control rod to be manually withdrawn a few inches to reconnect it to its drive mechanism; at 9:01 p.m. this rod was suddenly withdrawn too far, causing SL-1 to go prompt critical instantly. In four milliseconds, the heat generated by the resulting enormous power surge caused water surrounding the core to begin to explosively vaporize. The water vapor caused a pressure wave to strike the top of the reactor vessel, causing water and steam to spray from the top of the vessel. This extreme form of water hammer propelled control rods, shield plugs, and the entire reactor vessel upwards. A later investigation concluded that the 26,000-pound (12,000 kg) vessel had jumped 9 feet 1 inch (2.77 m) and the upper control rod drive mechanisms had struck the ceiling of the reactor building prior to settling back into its original location. The spray of water and steam knocked two operators onto the floor, killing one and severely injuring another. One of the shield plugs on top of the reactor vessel impaled the third man through his groin and exited his shoulder, pinning him to the ceiling. The victims were Army Specialists John A. Byrnes (age 27) and Richard Leroy McKinley (age 22), and Navy Seabee Construction Electrician First Class (CE1) Richard C. Legg (age 26). It was later established that Byrnes (the reactor operator) had lifted the rod and caused the excursion, Legg (the shift supervisor) was standing on top of the reactor vessel and was impaled and pinned to the ceiling, and McKinley, the trainee who stood nearby, was later found alive by rescuers. All three men succumbed to injuries from physical trauma, however the radiation from the nuclear excursion would have given the men no chance of survival... There were no other people at the reactor site. The ending of the nuclear reaction was caused solely by the design of the reactor and the basic physics of heated water and core elements melting, separating the core elements and removing the moderator... The remains of the SL-1 reactor are now buried near the original site...
Просмотров: 202658 Jeff Quitney
Private SNAFU: Booby Traps 1944 US Army Training Film Cartoon, Mel Blanc, Bob Clampett
 
04:19
more at http://quickfound.net/links/military_news_and_links.html "Private Snafu learns about the hazards of enemy booby traps the hard way. This is one of 26 Private SNAFU ('Situation Normal, All Fouled Up) cartoons made by the US Army Signal Corps to educate and boost the morale the troops. Originally created by Theodore Geisel (Dr. Seuss) and Phil Eastman, most of the cartoons were produced by Warner Brothers Animation Studios - employing their animators, voice actors (primarily Mel Blanc) and Carl Stalling's music." NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=vWNpnkW1sVk Public domain film slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). more Private Snafu: The Home Front http://www.youtube.com/watch?v=vGmIhhMi8cg Spies http://www.youtube.com/watch?v=WJn_aB4FjpI Snafuperman http://www.youtube.com/watch?v=Op6-V5x8XHQ http://en.wikipedia.org/wiki/Private_Snafu Private Snafu is the title character of a series of black-and-white American instructional cartoon shorts produced between 1943 and 1945 during World War II. The character was created by director Frank Capra, chairman of the U.S. Army Air Force First Motion Picture Unit, and most were written by Theodor "Dr. Seuss" Geisel, Philip D. Eastman, and Munro Leaf. Although the United States Army gave Walt Disney the first crack at creating the cartoons, Leon Schlesinger of the Warner Bros. animation studio underbid Disney by two-thirds and won the contract. Disney had also demanded exclusive ownership of the character, and merchandising rights. Nel (2007) shows the goal was to help enlisted men with weak literacy skills learn through animated cartoons (and also supplementary comic books). They featured simple language, racy illustrations, no profanity, and subtle moralizing. Private Snafu did everything wrong, so that his negative example taught basic lessons about secrecy, disease prevention, and proper military protocols. Private Snafu cartoons were a military secret—for the armed forces only. Surveys to ascertain the soldiers' film favorites showed that the Snafu cartoons usually rated highest or second highest. Each cartoon was produced in six weeks, compared to the six months usually taken for short cartoons of the same kind... Most of the Private Snafu shorts are educational, and although the War Department had to approve the storyboards, the Warner directors were allowed great latitude in order to keep the cartoons entertaining... The Snafu shorts are notable because they were produced during the Golden Age of Warner Bros. animation. Directors such as Chuck Jones, Friz Freleng, Bob Clampett, and Frank Tashlin worked on them, and their characteristic styles are in top form. P. D. Eastman was a writer and storyboard artist for the Snafu shorts. Voice characterizations were provided by the celebrated Mel Blanc (Private Snafu's voice was similar to Blanc's Bugs Bunny characterization, and Bugs himself actually made cameos in the Snafu episodes Gas and Three Brothers). Toward the end of the war, other studios began producing Snafu shorts as well (the Army accused Schlesinger of padding his bills), though some of these never made it to celluloid before the war ended. The Snafu films are also partly responsible for keeping the animation studios open during the war—by producing such training films, the studios were declared an essential industry. After the war, the Snafu cartoons went largely forgotten. Prints eventually wound up in the hands of collectors, and these form the basis for The Complete, Uncensored Private Snafu, a VHS and DVD collection from Bosko Video...
Просмотров: 258681 Jeff Quitney
"The Saturn Propulsion System" Project Apollo Rocket Engines 1962 NASA Marshall Space Flight Center
 
14:11
more at http://scitech.quickfound.net/astro/project_apollo.html "The theory of reaction engines and the application to the Saturn propulsion system." Includes film of the first Saturn I launch in 1961 (SA-1). NASA f HQ-a77 I couldn't do much to improve the color on this one, but the sound cleaned up nicely. NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=wq3phcv-NbI Reupload of a previously uploaded film with improved sound and video. Public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and 1-pass exposure & color correction applied (cannot be ideal in all scenes). The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). Rocket engine development history: V-2 engine led to Navaho engine led to Atlas engine led to Saturn H-1 engine. http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/SM-64_Navajo ...Development of the first stage rocket engine for the Navaho began with two refurbished V-2 engines in 1947. That same year, the phase II engine was designed, the XLR-41-NA-1, a simplified version of the V-2 engine made from American parts. The phase III engine, XLR-43-NA-1 (also called 75K), adopted a cylindrical combustion chamber with the experimental German impinging-stream injector plate. Engineers at North American were able to solve the combustion stability problem, which had prevented it being used in the V-2, and the engine was successfully tested at full power in 1951. The Phase IV engine, XLR-43-NA-3 (120K), replaced the poorly cooled heavy German engine wall with a brazed tubular ("spaghetti") construction, which was becoming the new standard method for regenerative cooling in American engines. A dual-engine version of this, XLR-71-NA-1 (240K), was used in the G-26 Navaho. With improved cooling, a more powerful kerosene-burning version was developed for the triple-engine XLR-83-NA-1 (405K), used in the G-38 Navaho. With all the elements of a modern engine (except a bell-shaped nozzle), this led to designs for the Atlas, Thor and Titan engines... http://en.wikipedia.org/wiki/H-1_(rocket_engine) Rocketdyne's H-1 is a 205,000 lbf (910 kN) thrust liquid-propellant rocket engine burning LOX and RP-1. The H-1 was developed for use in the S-IB first stage of the Saturn I and Saturn IB rockets, where it was used in clusters of eight engines. After the Apollo program, surplus H-1 engines were rebranded and reworked as the Rocketdyne RS-27 engine with first usage on the Delta 2000 series in 1974... http://en.wikipedia.org/wiki/F-1_(rocket_engine) The F-1 is a rocket engine developed by Rocketdyne and used in the Saturn V. Five F-1 engines were used in the S-IC first stage of each Saturn V, which served as the main launch vehicle in the Apollo program. The F-1 is still the most powerful single-chamber liquid-fueled rocket engine ever developed. The RD-170 has slightly more thrust, using a cluster of four smaller combustion chambers and nozzles... http://en.wikipedia.org/wiki/J-2_(rocket_engine) The J-2 was a liquid-fuel cryogenic rocket engine used on NASA's Saturn IB and Saturn V launch vehicles. Built in the United States of America by Rocketdyne, the J-2 burned cryogenic liquid hydrogen & liquid oxygen propellants, with each engine producing 1,033.1 kN (232,250 lbf) of thrust in vacuum. Development of the engine began in the 1960s, with the first flight, AS-201, occurring on 26 February 1966. The J-2 underwent several minor upgrades over its operational history to improve the engine's performance, with two major upgrade programs, the de Laval nozzle-type J-2S and aerospike-type J-2T, being cancelled after the conclusion of the Apollo program. Five J-2 engines were used on the Saturn V's S-II second stage, and one J-2 was used on the S-IVB upper stage used on both the Saturn IB and Saturn V. Proposals also existed to use various numbers of J-2 engines in the upper stages of an even larger rocket, the planned Nova. The J-2 was America's largest production liquid hydrogen fuelled rocket engine before the RS-25 Space Shuttle Main Engine, and a modernised version of the engine, the J-2X, is intended for use on the Earth Departure Stage of NASA's Space Shuttle replacement, the Space Launch System. Unlike most liquid-fuelled rocket engines in service at the time, the J-2 was designed to be re-started once after shutdown when flown on the Saturn V. The first burn, lasting about two minutes, placed the Apollo spacecraft into a low Earth parking orbit. After the crew verified that the spacecraft was operating nominally, the J-2 was re-ignited for translunar injection, a 6.5 minute burn which accelerated the vehicle to a course for the Moon... http://en.wikipedia.org/wiki/Saturn_I http://en.wikipedia.org/wiki/Saturn_IB http://en.wikipedia.org/wiki/Saturn_V
Просмотров: 259227 Jeff Quitney
Nuclear Ramjet (Project Pluto) to Drive "Big Stick" SLAM Missile circa 1959 USAF-Convair
 
09:02
more at http://quickfound.net Late 50's Convair proposal for "The Big Stick", a Supersonic Low Altitude Missile (SLAM) driven by a nuclear reactor-powered ramjet. The missile could loiter in flight for long periods before dashing at Mach 3 to the targets, delivering multiple atomic bombs. It also would leave a stream of nuclear fallout from its reactor in its wake. SLAM development was cancelled in 1964. Public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Supersonic_Low_Altitude_Missile The Supersonic Low Altitude Missile or SLAM... was a canceled U.S. Air Force project conceived around 1955. Although it never proceeded beyond the initial design and testing phase before being declared obsolete, it represented several radical innovations as a Nuclear delivery system. The SLAM was designed to complement the doctrine of mutually assured destruction... In the event of nuclear war it was intended to fly below the cover of enemy radar at supersonic speeds, and deliver thermonuclear warheads to roughly 16 targets. The primary innovation was the engine of the aircraft, which was developed under the aegis of a separate project code-named Project Pluto, after the Roman god of the underworld. It was a ramjet that used nuclear fission to superheat incoming air instead of chemical fuel. Project Pluto produced two working prototypes of this engine, the Tory-IIA and the Tory-IIC, which were successfully tested in the Nevada desert. Special ceramics had to be developed to meet the stringent weight and tremendous heat tolerances demanded of the SLAM's reactor. These were developed by the Coors Porcelain Company. The reactor itself was designed at the Lawrence Radiation Laboratory. The use of a nuclear engine in the airframe promised to give the missile staggering and unprecedented low-altitude range, estimated to be roughly 113,000 miles (182,000 km) (over four and a half times the equatorial circumference of the earth). The engine also acted as a secondary weapon for the missile: direct neutron radiation from the virtually unshielded reactor would sicken, injure, and/or kill living things beneath the flight path; the stream of fallout left in its wake would poison enemy territory; and its strategically selected crash site would receive intense radioactive contamination. In addition, the sonic waves given off by its passage would damage ground installations. Another revolutionary aspect of the SLAM was its reliance on automation. It would have the mission of a long-range bomber, but would be completely unmanned: accepting radioed commands up to its failsafe point, whereafter it would rely on a Terrain Contour Matching (TERCOM) radar system to navigate to preprogrammed targets. Although a prototype of the airframe was never constructed, the SLAM was to be a wingless, fin-guided aircraft. Apart from the ventral ram-air intake it was very much in keeping with traditional missile design. Its estimated airspeed at thirty thousand feet was Mach 4.2. The SLAM program was scrapped on July 1, 1964. By this time serious questions about its viability had been raised, such as how to test a device that would emit copious amounts of radioactive exhaust from its unshielded reactor core in flight, as well as its efficacy and cost. ICBMs promised swifter delivery to targets, and because of their speed (the Thor traveled at roughly Mach 12) and trajectory were considered virtually unstoppable. The SLAM was also being outpaced by advances in defensive ground radar, which threatened to render its stratagem of low-altitude evasion ineffective... http://en.wikipedia.org/wiki/Project_Pluto Project Pluto was a United States government program to develop nuclear powered ramjet engines for use in cruise missiles. Two experimental engines were tested at the United States Department of Energy Nevada Test Site (NTS) in 1961 and 1964... History On January 1, 1957, the U.S. Air Force and the U.S. Atomic Energy Commission selected the Lawrence Livermore National Laboratory's (LLNL) predecessor, the Lawrence Radiation Laboratory, to study the feasibility of applying heat from nuclear reactors to ramjet engines. This research became known as "Project Pluto". The work was directed by Dr. Ted Merkle, leader of the laboratory's R-Division... On May 14, 1961, the world's first nuclear ramjet engine, "Tory-IIA", mounted on a railroad car, roared to life for a few seconds. Three years later, "Tory-IIC" was run for five minutes at full power... On July 1, 1964, seven years and six months after it was started, "Project Pluto" was canceled...
Просмотров: 198946 Jeff Quitney
Private SNAFU Censored 1944 US Army Training Cartoon, Mel Blanc, Frank Tashlin
 
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more at http://quickfound.net/links/military_news_and_links.html Private Snafu learns he should watch what he writes in letters to home. "Originally created by Theodore Geisel (Dr. Seuss) and Phil Eastman, most of the cartoons were produced by Warner Brothers Animation Studios - employing their animators, voice actors (primarily Mel Blanc) and Carl Stalling's music." Public domain film from the US National Archives slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). more Private Snafu: Booby Traps: https://www.youtube.com/watch?v=-PbDa-NlX9A The Home Front http://www.youtube.com/watch?v=vGmIhhMi8cg Spies http://www.youtube.com/watch?v=WJn_aB4FjpI Snafuperman http://www.youtube.com/watch?v=Op6-V5x8XHQ Fighting Tools: https://www.youtube.com/watch?v=kRyUAUl2q5M Rumors: https://www.youtube.com/watch?v=rEdboFx1mK8 http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Private_Snafu Private Snafu is the title character of a series of black-and-white American instructional cartoon shorts produced between 1943 and 1945 during World War II. The character was created by director Frank Capra, chairman of the U.S. Army Air Force First Motion Picture Unit, and most were written by Theodor "Dr. Seuss" Geisel, Philip D. Eastman, and Munro Leaf. Although the United States Army gave Walt Disney the first crack at creating the cartoons, Leon Schlesinger of the Warner Bros. animation studio underbid Disney by two-thirds and won the contract. Disney had also demanded exclusive ownership of the character, and merchandising rights. Nel (2007) shows the goal was to help enlisted men with weak literacy skills learn through animated cartoons (and also supplementary comic books). They featured simple language, racy illustrations, no profanity, and subtle moralizing. Private Snafu did everything wrong, so that his negative example taught basic lessons about secrecy, disease prevention, and proper military protocols. Private Snafu cartoons were a military secret—for the armed forces only. Surveys to ascertain the soldiers' film favorites showed that the Snafu cartoons usually rated highest or second highest. Each cartoon was produced in six weeks, compared to the six months usually taken for short cartoons of the same kind... Most of the Private Snafu shorts are educational, and although the War Department had to approve the storyboards, the Warner directors were allowed great latitude in order to keep the cartoons entertaining... The Snafu shorts are notable because they were produced during the Golden Age of Warner Bros. animation. Directors such as Chuck Jones, Friz Freleng, Bob Clampett, and Frank Tashlin worked on them, and their characteristic styles are in top form. P. D. Eastman was a writer and storyboard artist for the Snafu shorts. Voice characterizations were provided by the celebrated Mel Blanc (Private Snafu's voice was similar to Blanc's Bugs Bunny characterization, and Bugs himself actually made cameos in the Snafu episodes Gas and Three Brothers). Toward the end of the war, other studios began producing Snafu shorts as well (the Army accused Schlesinger of padding his bills), though some of these never made it to celluloid before the war ended. The Snafu films are also partly responsible for keeping the animation studios open during the war—by producing such training films, the studios were declared an essential industry. After the war, the Snafu cartoons went largely forgotten. Prints eventually wound up in the hands of collectors, and these form the basis for The Complete, Uncensored Private Snafu, a VHS and DVD collection from Bosko Video...
Просмотров: 2377423 Jeff Quitney
Fairchild Republic A-10 Thunderbolt II (Warthog) Capabilities and Sortie Surge ~ 1977 US Air Force
 
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Aircraft playlist: https://www.youtube.com/playlist?list=PL23A1203602337689 more at: http://scitech.quickfound.net/aviation_news_and_search.html Fairchild Republic A-10 Thunderbolt II attack jet aircraft. Originally a public domain film from the US Air Force, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). https://en.wikipedia.org/wiki/Fairchild_Republic_A-10_Thunderbolt_II Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ The Fairchild Republic A-10 Thunderbolt II is an American twin-engine, straight wing jet aircraft developed by Fairchild-Republic in the early 1970s. It entered service in 1976, and is the only United States Air Force production aircraft designed solely for close air support, including attacking tanks, armored vehicles, and other ground targets. The A-10 was designed around the 30 mm GAU-8 Avenger rotary cannon that is its primary armament. The A-10's airframe was designed for durability, with measures such as 1,200 pounds (540 kg) of titanium armor to protect the cockpit and aircraft systems, enabling it to absorb a significant amount of damage and continue flying. Its short takeoff and landing capability permits operation from airstrips close to the front lines, while its simple design enables maintenance at forward bases with limited facilities. The A-10A single-seat variant was the only version built, though one A-10A was converted to an A-10B twin-seat version. In 2005, a program was begun to upgrade remaining A-10A aircraft to the A-10C configuration. The A-10's official name comes from the Republic P-47 Thunderbolt of World War II, a fighter that was particularly effective at close air support. The A-10 is more commonly known by its nicknames "Warthog" or "Hog". Its secondary mission is to provide forward air controller - airborne (FAC-A) support, by directing other aircraft in attacks on ground targets. Aircraft used primarily in this role are designated OA-10. With a variety of upgrades and wing replacements, the A-10's service life may be extended to 2028, though there are proposals to retire it sooner...
Просмотров: 41688 Jeff Quitney
H-Bomb Armed B-52 Crash Cleanup in Greenland: "Crested Ice" 1968 USAF Strategic Air Command
 
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Nuclear weapons playlist: https://www.youtube.com/playlist?list=PL4CD7F0970A5F16AB "STRATEGIC AIR COMMAND SEMIANNUAL FILM REPORT... CRESTED ICE PROJECT..." From US Air Force Strategic Air Command Film Report FR-818 Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/1968_Thule_Air_Base_B-52_crash On 21 January 1968, an aircraft accident (sometimes known as the Thule affair or Thule accident (/ˈtuːli/); Danish: Thuleulykken) involving a United States Air Force (USAF) B-52 bomber occurred near Thule Air Base in the Danish territory of Greenland. The aircraft was carrying four hydrogen bombs on a Cold War "Chrome Dome" alert mission over Baffin Bay when a cabin fire forced the crew to abandon the aircraft before they could carry out an emergency landing at Thule Air Base. Six crew members ejected safely, but one who did not have an ejection seat was killed while trying to bail out. The bomber crashed onto sea ice in North Star Bay, Greenland, causing the conventional explosives aboard to detonate and the nuclear payload to rupture and disperse, which resulted in radioactive contamination. The United States and Denmark launched an intensive clean-up and recovery operation, but the secondary stage of one of the nuclear weapons could not be accounted for after the operation completed. USAF Strategic Air Command "Chrome Dome" operations were discontinued immediately after the accident, which highlighted the safety and political risks of the missions. Safety procedures were reviewed and more stable explosives were developed for use in nuclear weapons. ...Workers involved in the clean-up program have been campaigning for compensation for radiation-related illnesses they experienced in the years after the accident... In 1960, the USAF Strategic Air Command (SAC) began Operation Chrome Dome, a Cold War airborne alert program devised by General Thomas S. Power to fly nuclear-armed B-52 Stratofortresses to the borders of the Soviet Union. The flights were scheduled to ensure that twelve bombers were aloft at all times... Beginning in 1961, B-52 bombers also flew secret "Hard Head" missions (or "Thule Monitor Missions") over Thule Air Base with the purpose of maintaining visual surveillance of the base's strategically important Ballistic Missile Early Warning System (BMEWS)... On 21 January 1968, a B-52G Stratofortress, serial number 58-0188, with the callsign "HOBO 28" from the 380th Strategic Bomb Wing at Plattsburgh Air Force Base, New York was assigned the "Hard Head" mission over Thule and nearby Baffin Bay... At 15:22 EST, about six hours into the flight and 90 miles (140 km) south of Thule Air Base, Haug declared an emergency. He told Thule air traffic control that he had a fire on board... ...the captain realized he would not be able to land the aircraft... and when he confirmed that the aircraft was directly over the lights of Thule Air Base, the... crewmen ejected... The pilotless aircraft initially continued north, then turned left through 180° and crashed onto sea ice in North Star Bay at a relatively shallow angle of 20 degrees—about 7.5 miles (12.1 km) west of Thule Air Base—at 15:39 EST. The conventional high explosive (HE) components of four 1.1 megaton B28FI model hydrogen bombs detonated on impact, spreading radioactive material over a large area in a manner similar to a dirty bomb. "Weak links" in the weapon design ensured that a nuclear explosion was not triggered. The extreme heat generated by the burning of 225,000 pounds (102 t) of jet fuel during the five to six hours after the crash melted the ice sheet, causing wreckage and munitions to sink to the ocean floor... The accident was designated a "Broken Arrow"—a United States military term that describes an accident involving a nuclear weapon... Project Crested Ice South of the impact area, a 400-foot (120 m) by 2,200-foot (670 m) blackened patch was visible where fuel from the aircraft had burned—this area was highly contaminated with JP-4 aviation fuel and radioactive elements that included plutonium, uranium, americium and tritium. Plutonium levels as high as 380 mg/m2 were registered in the area... By the time the operation concluded, 700 specialized personnel from both countries and more than 70 United States government agencies had worked for nine months to clean up the site, often without adequate protective clothing or decontamination measures... Project Crested Ice ended on 13 September 1968...
Просмотров: 27090 Jeff Quitney
Off-Base Activities: "Killjoy Was Here!" 1956 US Air Force Animated Training Film Cartoon
 
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USAF Training Film playlist: https://www.youtube.com/playlist?list=PL8F26D920AA815835 more at http://quickfound.net/links/military_news_and_links.html Airman Killjoy makes enemies, then Airman Archie tries to make friends, with the locals near USAF bases. "This film uses animation to instruct U.S. Air Force personnel on their responsibilities to communities surrounding their installations." US Air Force Training Film SFP-366 Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/List_of_countries_with_overseas_military_bases#United_States ...The establishment of military bases abroad enable a country to project power, e.g. to conduct expeditionary warfare, and thereby influence events abroad. Depending on their size and infrastructure, they can be used as staging areas or for logistical, communications and/or intelligence support. Many conflicts throughout modern history have resulted in overseas military bases being established in large numbers by world powers, and the existence of bases abroad has served countries having them in achieving political and military goals. The British Empire and other colonial powers established overseas military bases in many of their colonies during the First and Second World Wars, where useful, and actively sought rights to facilities where needed for strategic reasons. At one time, establishing coaling stations for naval ships was important. During the Cold War, the United States and the Soviet Union established military bases where they could within their respective spheres of influence, and actively sought influence where needed. More recently, the War on Terror has resulted in overseas military bases being established in the Middle East. Whilst the overall number of overseas military bases has fallen since 1945, France, Russia, the United Kingdom and the United States still possess a substantial number. Smaller numbers of overseas military bases are operated by India, Italy, Japan and Turkey. The United States is the largest operator of military bases abroad, with 38 "named bases" having active duty, national guard/reserve, and/or civilian personnel as of September 30, 2014. Its largest, in terms of personnel, was Ramstein AB, in Germany, with almost 9,200 personnel... United States - Afghanistan - Camp Dwyer; Forward Operating Base Delhi; Forward Operating Base Geronimo; Firebase Fiddler's Green; PB Jaker - Australia - Pine Gap Bahrain - Naval Support Activity Bahrain; Isa Air Base Belgium - Chièvres Air Base; Kleine Brogel Air Base Brazil - United States Naval Support Detachment, São Paulo British Indian Ocean Territory - Naval Support Facility Diego Garcia - Bulgaria - Aitos Logistics Center; Bezmer Air Base; Graf Ignatievo Air Base; Novo Selo Range - Cuba - Guantanamo Bay Naval Base - Djibouti - Camp Lemonnier - Germany - US Army installations in Germany; Panzer Kaserne; Ramstein Air Base; Spangdahlem Air Base - Greece - Naval Support Activity Souda Bay[41] - Greenland - Thule Air Base - Honduras - Soto Cano Air Base - Israel - Port of Haifa (United States Sixth Fleet); Dimona Radar Facility - Italy - US Army installations in Italy; Naval Air Station Sigonella; Naval Support Activity Naples; Aviano Air Base; Darby Military Community - Japan - United States Forces Japan - Kosovo - Camp Bondsteel - Kuwait - Ali Al Salem Air Base; Camp Arifjan; Camp Buehring; Kuwait Naval Base - Netherlands - Volkel Air Base - Norway - 426th Air Base Squadron at Sola Air Station - Oman - RAFO Masirah; RAFO Thumrait - Portugal - Lajes Field - Qatar - Al Udeid Air Base - Saudi Arabia - 64th Air Expeditionary Group - Singapore - Paya Lebar Air Base - South Korea - United States Forces Korea - Spain - Morón Air Base; Naval Station Rota - Turkey - Incirlik Air Base; Izmir Air Station - United Arab Emirates - Al Dhafra Air Base; Port of Jebel Ali; Fujairah Naval Base - United Kingdom - RAF Alconbury; RAF Croughton; RAF Lakenheath; RAF Menwith Hill; RAF Mildenhall
Просмотров: 198106 Jeff Quitney
Car Brakes: "Hydraulics" 1936 Chevrolet Auto Mechanics
 
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more at http://auto-parts.quickfound.net "PRINCIPLES OF HYDRAULICS EXPLAINED, CENTERING ON THE VALUE FOR SAFETY & COMFORT OF HYDRAULIC BRAKES." NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=mTO7vlITLek Public domain film from the Library of Congress Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Drum_brake A drum brake is a brake in which the friction is caused by a set of shoes or pads that press against a rotating drum-shaped part called a brake drum. The term "drum brake" usually means a brake in which shoes press on the inner surface of the drum. When shoes press on the outside of the drum, it is usually called a clasp brake. Where the drum is pinched between two shoes, similar to a conventional disk brake, it is sometimes called a "pinch drum brake", although such brakes are relatively rare. A related type of brake uses a flexible belt or "band" wrapping around the outside of a drum, called a band brake. The modern automobile drum brake was invented in 1902 by Louis Renault, whose unique genius inspired him to use woven asbestos lining for the drum brakes lining as there were no other alternatives that dissipated heat like the asbestos lining, though a less-sophisticated drum brake had been used by Maybach a year earlier... Components Some of the major components of the drum brake assembly are the back plate, the brake drum and shoe, the wheel cylinder, and various springs and pins. Back plate The back plate serves as the base on which all the components are assembled. It attaches to the axle and forms a solid surface for the wheel cylinder, brake shoes and assorted hardware. Since all the braking operations exert pressure on the back plate, it needs to be very strong and wear-resistant. Levers for emergency or parking brakes, and automatic brake-shoe adjuster were also added in recent years... Brake drum The brake drum is generally made of a special type of cast iron which is heat-conductive and wear-resistant. It is positioned very close to the brake shoe without actually touching it, and rotates with the wheel and axle. As the lining is pushed against the inner surface of the drum, friction heat can reach as high as 600 °F (316 °C). Wheel cylinder One wheel cylinder is used for each wheel. Two pistons operate the shoes, one at each end of the wheel cylinder. When hydraulic pressure from the master cylinder acts upon the piston cup, the pistons are pushed toward the shoes, forcing them against the drum. When the brakes are not being applied, the piston is returned to its original position by the force of the brake shoe return springs. The parts of the wheel cylinder are as follows: Brake shoe Brake shoes are typically made of two pieces of sheet steel welded together. The friction material is either rivetted to the lining table or attached with adhesive. The crescent-shaped piece is called the Web and contains holes and slots in different shapes for return springs, hold-down hardware, parking brake linkage and self-adjusting components. All the application force of the wheel cylinder is applied through the web to the lining table and brake lining. The edge of the lining table generally has three "V"-shaped notches or tabs on each side called nibs. The nibs rest against the support pads of the backing plate to which the shoes are installed. Each brake assembly has two shoes, a primary and secondary. The primary shoe is located toward the front of the vehicle and has the lining positioned differently than the secondary shoe. Quite often the two shoes are interchangeable, so close inspection for any variation is important. Linings must be resistant against heat and wear and have a high friction coefficient unaffected by fluctuations in temperature and humidity. Materials which make up the brake shoe include, friction modifiers (which can include can include graphite and cashew nut shells), powdered metal such as lead, zinc, brass, aluminium and other metals that resist heat fade, binders, curing agents and fillers such as rubber chips to reduce brake noise. Automatic self-adjuster The self-adjuster is used to adjust the distance between the brake shoe and the drum automatically as brake shoes wear...
Просмотров: 132052 Jeff Quitney
Man in 457 mph Wind: "Human Tolerance to Wind Blasts" 1946 NACA  Langley Research Center
 
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NEW VERSION with improved video: https://www.youtube.com/watch?v=LfBvXC9MQj8 more at http://scitech.quickfound.net/ "Test conducted in 1946 where a human subject was exposed to blasts of air. The test was performed at NASA Langley Research Center's 8 ft High Speed Tunnel." Silent. Public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Wind Wind is the flow of gases on a large scale. On Earth, wind consists of the bulk movement of air. In outer space, solar wind is the movement of gases or charged particles from the sun through space, while planetary wind is the outgassing of light chemical elements from a planet's atmosphere into space. Winds are commonly classified by their spatial scale, their speed, the types of forces that cause them, the regions in which they occur, and their effect. The strongest observed winds on a planet in our solar system occur on Neptune and Saturn. In meteorology, winds are often referred to according to their strength, and the direction from which the wind is blowing. Short bursts of high speed wind are termed gusts. Strong winds of intermediate duration (around one minute) are termed squalls. Long-duration winds have various names associated with their average strength, such as breeze, gale, storm, hurricane, and typhoon. Wind occurs on a range of scales, from thunderstorm flows lasting tens of minutes, to local breezes generated by heating of land surfaces and lasting a few hours, to global winds resulting from the difference in absorption of solar energy between the climate zones on Earth. The two main causes of large-scale atmospheric circulation are the differential heating between the equator and the poles, and the rotation of the planet (Coriolis effect). Within the tropics, thermal low circulations over terrain and high plateaus can drive monsoon circulations. In coastal areas the sea breeze/land breeze cycle can define local winds; in areas that have variable terrain, mountain and valley breezes can dominate local winds. In human civilization, wind has inspired mythology, influenced the events of history, expanded the range of transport and warfare, and provided a power source for mechanical work, electricity and recreation. Wind powers the voyages of sailing ships across Earth's oceans. Hot air balloons use the wind to take short trips, and powered flight uses it to increase lift and reduce fuel consumption. Areas of wind shear caused by various weather phenomena can lead to dangerous situations for aircraft. When winds become strong, trees and man-made structures are damaged or destroyed. Winds can shape landforms, via a variety of aeolian processes... http://crgis.ndc.nasa.gov/historic/641 8-Foot High Speed Tunnel As interest in the field of high-speed aerodynamics increased in the early 1930s, Langley's existing wind tunnels proved too small and underpowered for effective high-speed aircraft testing. Understanding that a new facility would give U.S. engineers a decided advantage in the aeronautical field, Langley's director of research George W. Lewis authorized the design and construction of a larger high speed wind tunnel in 1933. Construction of the 8-Foot High Speed Tunnel (HST) was funded by the Public Works Administration (PWA) and completed in 1936 at a cost of $266,000... The world's first large high speed tunnel, the HST proved vital during World War II... http://en.wikipedia.org/wiki/John_Stapp#Wind-blast_experiments ...Wind-blast experiments Stapp also participated in wind-blast experiments, in which he flew in jet aircraft at high speeds to determine whether or not it was safe for a pilot to remain with his aircraft if the canopy should accidentally blow off. Stapp stayed with his aircraft at a speed of 570 mph (917 km/h), with the canopy removed, and suffered no injurious effects from the wind blasts. Among these experiments was one of the first high-altitude skydives, executed by Stapp himself. He also supervised research programs in the fields of human factors in escape from aircraft and human tolerance to abrupt acceleration and deceleration...
Просмотров: 1388673 Jeff Quitney
Stirling Cycle Engine: "The Stirling Engine: A Wave of the Future" 1992 NASA
 
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more at http://auto-parts.quickfound.net/ "This video describes the Stirling engine, an external combustion engine which creates heat energy to power the motor, and can use many types of fuel. It can be used for both stationary and propulsion purposes and has advantages of better fuel economy and cleaner exhaust than internal combustion engines. The engine is shown being road tested at Langley Air Force Base." Public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization. http://en.wikipedia.org/wiki/Stirling_engine A Stirling engine is a heat engine operating by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work. Or more specifically, a closed-cycle regenerative heat engine with a permanently gaseous working fluid, where closed-cycle is defined as a thermodynamic system in which the working fluid is permanently contained within the system, and regenerative describes the use of a specific type of internal heat exchanger and thermal store, known as the regenerator. It is the inclusion of a regenerator that differentiates the Stirling engine from other closed cycle hot air engines. Originally conceived in 1816 as an industrial prime mover to rival the steam engine, its practical use was largely confined to low-power domestic applications for over a century. The Stirling engine is noted for its high efficiency compared to steam engines, quiet operation, and the ease with which it can use almost any heat source. This compatibility with alternative and renewable energy sources has become increasingly significant as the price of conventional fuels rises, and also in light of concerns such as peak oil and climate change. This engine is currently exciting interest as the core component of micro combined heat and power (CHP) units, in which it is more efficient and safer than a comparable steam engine... Robert Stirling was the Scottish inventor of the first practical example of a closed cycle air engine in 1816... Functional description The engine is designed so that the working gas is generally compressed in the colder portion of the engine and expanded in the hotter portion resulting in a net conversion of heat into work. An internal Regenerative heat exchanger increases the Stirling engine's thermal efficiency compared to simpler hot air engines lacking this feature. Key components As a consequence of closed cycle operation, the heat driving a Stirling engine must be transmitted from a heat source to the working fluid by heat exchangers and finally to a heat sink. A Stirling engine system has at least one heat source, one heat sink and up to five heat exchangers. Some types may combine or dispense with some of these. Heat source The heat source may be provided by the combustion of a fuel and, since the combustion products do not mix with the working fluid and hence do not come into contact with the internal parts of the engine, a Stirling engine can run on fuels that would damage other types of engines' internals... Other suitable heat sources include concentrated solar energy, geothermal energy, nuclear energy, waste heat and bioenergy. If solar power is used as a heat source, regular solar mirrors and solar dishes may be utilised. The use of Fresnel lenses and mirrors has also been advocated, for example in planetary surface exploration... Heater / hot side heat exchanger In small, low power engines this may simply consist of the walls of the hot space(s) but where larger powers are required a greater surface area is needed in order to transfer sufficient heat. Typical implementations are internal and external fins or multiple small bore tubes. Designing Stirling engine heat exchangers is a balance between high heat transfer with low viscous pumping losses and low dead space (unswept internal volume). With engines operating at high powers and pressures, the heat exchangers on the hot side must be made of alloys that retain considerable strength at temperature and that will also not corrode or creep. Regenerator In a Stirling engine, the regenerator is an internal heat exchanger and temporary heat store placed between the hot and cold spaces such that the working fluid passes through it first in one direction then the other. Its function is to retain within the system that heat which would otherwise be exchanged with the environment... The primary effect of regeneration in a Stirling engine is to increase the thermal efficiency by 'recycling' internal heat which would otherwise pass through the engine irreversibly...
Просмотров: 209618 Jeff Quitney
The Naval Gun at Iwo Jima 1945 US Navy Tactical Report; Battleship Gun Performance
 
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US Navy Training Film playlist: https://www.youtube.com/playlist?list=PLA40407C12E5E35A7 World War II playlist: https://www.youtube.com/playlist?list=PL3E5ED4749AE3CD2C more at http://quickfound.net/links/military_news_and_links.html "The Naval Gun at Iwo Jima: Destruction of Defenses Preceding the Landing Assault" US Navy Tactical Report MN-5562 Originally a public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Battle_of_Iwo_Jima Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ The Battle of Iwo Jima (19 February -- 26 March 1945), or Operation Detachment, was a major battle in which the United States fought for and captured the island of Iwo Jima from the Empire of Japan. The U.S. invasion, charged with the mission of capturing the three airfields on Iwo Jima, resulted in some of the fiercest fighting in the Pacific Campaign of World War II. The Imperial Japanese Army positions on the island were heavily fortified, with a vast network of bunkers, hidden artillery, and 18 km (11 mi) of underground tunnels. The Americans were covered by extensive naval and air support, capable of delivering an enormous amount of firepower onto the Japanese positions. The battle was the first American attack on the Japanese Home Islands, and the Imperial soldiers defended their positions tenaciously. Iwo Jima was also the only U.S. Marine battle where the American overall casualties exceeded the Japanese, although Japanese combat deaths numbered 3 times that of Americans. Of the 22,000 Japanese soldiers present at the beginning of the battle, only 216 were taken prisoner. The rest were killed or missing and assumed dead. Despite heavy fighting and casualties on both sides, Japanese defeat was assured from the start. The Americans possessed an overwhelming superiority in arms and numbers; this, coupled with the impossibility of Japanese retreat or reinforcement, ensured that there was no plausible scenario in which the U.S. could have lost the battle. The battle was immortalized by Joe Rosenthal's photograph of the raising of the U.S. flag on top of the 166 m (545 ft) Mount Suribachi by five Marines and one Navy Corpsman... Starting on 15 June 1944, the U.S. began strikes against Iwo Jima that would become the longest and most intense conflict in the Pacific theater. These would be a combination of naval assaults and bombings that would go on for almost one year. Major General Harry Schmidt requested a ten day shelling of the island before the land invasion, but was given only three, which were impaired by the weather conditions. Each heavy ship was given an area to fire on which combined with all the ships covered the entire island. A ship would fire for approximately six hours before stopping for a certain amount of time... Although the island was declared secure at 18:00 on 16 March 25 days after the landings, the 5th Marine Division still faced Kuribayashi's stronghold in a gorge 640 m (700 yd) long at the northwestern end of the island... A weapon heavily used in the Pacific was the United States M2A1 flamethrower... Of the 22,060 Japanese soldiers entrenched on the island, 21,844 died either from fighting or by ritual suicide. Only 216 were captured during the battle. According to the official Navy Department Library website, "The 36-day (Iwo Jima) assault resulted in more than 26,000 American casualties, including 6,800 dead." To put that into context, the 82-day Battle for Okinawa lasted from early April until mid-June 1945 and U.S. (5 Army and 2 Marine Corps Divisions) casualties were over 62,000 of whom over 12,000 were killed or missing ; while the Battle of the Bulge lasted 40 days (16 December 44 -- 25 January 45) with almost 90,000 U.S. casualties; 19,000 killed, 47,500 wounded, and 23,000 captured or missing. Iwo Jima was also the only U.S. Marine battle where the American casualties exceeded the Japanese, although Japanese combat deaths numbered three times as many American deaths... USS Bismarck Sea had also been lost, as the last U.S. aircraft carrier sunk in World War II... After Iwo Jima, it was estimated there were no more than 300 Japanese left alive in the island's warren of caves and tunnels. In fact, there were close to 3,000...
Просмотров: 413084 Jeff Quitney
Physics: Crystals 1958 Alan Holden - Bell Laboratories - PSSC Physical Science Study Committee
 
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Physical Science Study Committee Films (PSSC) playlist: https://www.youtube.com/playlist?list=PL_hX5wLdhf_KuXqv0QzMoNQYgR_nBxETx Physics & Physical Sciences playlist: https://www.youtube.com/playlist?list=PL_hX5wLdhf_JKIMNk88rKCkhpK73_qmHY "Explains how crystals are formed and why they are shaped as they are. Considers their actual growth under a microscope, how they may be grown, and the relation of these phenomena to the concept of atoms. From the PSSC Physics series. Blue Ribbon winner, American Film Festival." Your instructor is Alan Holden of Bell Laboratories. Public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Crystal A crystal or crystalline solid is a solid material whose constituents, such as atoms, molecules or ions, are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macroscopic single crystals are usually identifiable by their geometrical shape, consisting of flat faces with specific, characteristic orientations. The scientific study of crystals and crystal formation is known as crystallography. The process of crystal formation via mechanisms of crystal growth is called crystallization or solidification. The word crystal is derived from the Ancient Greek word κρύσταλλος (krustallos), meaning both “ice” and “rock crystal”, from κρύος (kruos), "icy cold, frost". Examples of large crystals include snowflakes, diamonds, and table salt. Most inorganic solids are not crystals but polycrystals, i.e. many microscopic crystals fused together into a single solid. Examples of polycrystals include most metals, rocks, ceramics, and ice. A third category of solids is amorphous solids, where the atoms have no periodic structure whatsoever. Examples of amorphous solids include glass, wax, and many plastics... The scientific definition of a "crystal" is based on the microscopic arrangement of atoms inside it, called the crystal structure. A crystal is a solid where the atoms form a periodic arrangement. (Quasicrystals are an exception, see below.) Not all solids are crystals. For example, when liquid water starts freezing, the phase change begins with small ice crystals that grow until they fuse, forming a polycrystalline structure. In the final block of ice, each of the small crystals (called "crystallites" or "grains") is a true crystal with a periodic arrangement of atoms, but the whole polycrystal does not have a periodic arrangement of atoms, because the periodic pattern is broken at the grain boundaries. Most macroscopic inorganic solids are polycrystalline, including almost all metals, ceramics, ice, rocks, etc. Solids that are neither crystalline nor polycrystalline, such as glass, are called amorphous solids, also called glassy, vitreous, or noncrystalline. These have no periodic order, even microscopically. There are distinct differences between crystalline solids and amorphous solids: most notably, the process of forming a glass does not release the latent heat of fusion, but forming a crystal does. A crystal structure (an arrangement of atoms in a crystal) is characterized by its unit cell, a small imaginary box containing one or more atoms in a specific spatial arrangement. The unit cells are stacked in three-dimensional space to form the crystal. The symmetry of a crystal is constrained by the requirement that the unit cells stack perfectly with no gaps. There are 219 possible crystal symmetries, called crystallographic space groups. These are grouped into 7 crystal systems, such as cubic crystal system (where the crystals may form cubes or rectangular boxes, such as halite shown at right) or hexagonal crystal system (where the crystals may form hexagons, such as ordinary water ice)...
Просмотров: 258077 Jeff Quitney
Propfan: "Back to Propellers" 1987 NASA Lewis Research Center Fuel Efficient Aircraft Propulsion
 
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more at http://scitech.quickfound.net/aviation_news_and_search.html "The video shows the unique propfan design. The propfan is designed to achieve the speeds and altitudes of jets while only using half the normal amount of fuel." Public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization. http://en.wikipedia.org/wiki/Propfan A propfan was first defined as a small diameter, highly loaded multiple bladed variable pitch propulsor having swept blades with thin advanced airfoil sections, integrated with a nacelle contoured to retard the airflow through the blades thereby reducing compressibility losses and designed to operate with a turbine engine and using a single stage reduction gear resulting in high performance. The propfan concept was first revealed by Carl Rohrbach and Bruce Metzger of the Hamilton Standard Division of United Technologies in 1975 and was patented by Robert Cornell and Carl Rohrbach of Hamilton Standard in 1979. Later work by General Electric on similar propulsors was done under the name unducted fan, which was a modified turbofan engine, with the fan placed outside the engine nacelle on the same axis as the compressor blades. Propfans are also known as ultra-high bypass (UHB) engines and, most recently, open flux rotor jet engines. The design is intended to offer the speed and performance of a turbofan, with the fuel economy of a turboprop... Limitations and solutions Propeller blade tip speed limit Turboprops have an optimum speed below about 450 mph (700 km/h). The reason is that all propellers lose efficiency at high speed, due to an effect known as wave drag that occurs just below supersonic speeds. This powerful form of drag has a sudden onset, and led to the concept of a sound barrier when it was first encountered in the 1940s. In the case of a propeller, this effect can happen any time the propeller is spun fast enough that the blade tips near the speed of sound, even if the aircraft is motionless on the ground. The most effective way to counteract this problem (to some degree) is by adding more blades to the propeller, allowing it to deliver more power at a lower rotational speed. This is why many World War II fighter designs started with two or three-blade propellers and by the end of the war were using up to five blades... A method of decreasing wave drag was discovered by German researchers in 1935—sweeping the wing backwards. Today, almost all aircraft designed to fly much above 450 mph (700 km/h) use a swept wing. In the 1970s, Hamilton Standard started researching propellers with similar sweep... The propfan concept was developed to deliver 35% better fuel efficiency than contemporary turbofans. In static and air tests on a modified Douglas DC-9, propfans reached a 30% improvement over the OEM turbofans. This efficiency came at a price, as one of the major problems with the propfan is noise... Aircraft with propfans - Antonov An-70 - Beriev A-40 - EcoJet - McDonnell Douglas MD-94X
Просмотров: 163474 Jeff Quitney
Auto Mechanics: Transmissions: "Fluid Coupling Principles of Operation" 1954 US Army 13min
 
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NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=YKHeqHMye4k more at http://auto-parts.quickfound.net/ "DEMONSTRATION OF FLUID COUPLING WITH THE USE OF A PLASTIC MODEL IN OPERATION AND A TRUCK IN ACTION." Public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization. http://en.wikipedia.org/wiki/Fluid_coupling A fluid coupling is a hydrodynamic device used to transmit rotating mechanical power. It has been used in automobile transmissions as an alternative to a mechanical clutch. It also has widespread application in marine and industrial machine drives, where variable speed operation and/or controlled start-up without shock loading of the power transmission system is essential. History The fluid coupling originates from the work of Dr. Hermann Föttinger, who was the chief designer at the AG Vulcan Works in Stettin. His patents from 1905 covered both fluid couplings and torque converters. In 1930 Harold Sinclair, working with the Daimler company, devised a transmission system using a fluid coupling and planetary gearing for buses in an attempt to mitigate the lurching he had experienced while riding on London buses during the 1920s. In 1939 General Motors Corporation introduced Hydramatic drive, the first fully automatic automotive transmission system installed in a mass produced automobile. The Hydramatic employed a fluid coupling. The first Diesel locomotives using fluid couplings were also produced in the 1930s. Overview A fluid coupling consists of three components, plus the hydraulic fluid: - The housing, also known as the shell (which must have an oil tight seal around the drive shafts), contains the fluid and turbines. - Two turbines (fan like components): - One connected to the input shaft; known as the pump or impellor, primary wheel input turbine - The other connected to the output shaft, known as the turbine, output turbine, secondary wheel or runner The driving turbine, known as the 'pump', (or driving torus[note 1]) is rotated by the prime mover, which is typically an internal combustion engine or electric motor. The impellor's motion imparts both outwards linear and rotational motion to the fluid. The hydraulic fluid is directed by the 'pump' whose shape forces the flow in the direction of the 'output turbine' (or driven torus[note 1]). Here, any difference in the angular velocities of 'input stage' and 'output stage' result in a net force on the 'output turbine' causing a torque; thus causing it to rotate in the same direction as the pump. The motion of the fluid is effectively toroidal - travelling in one direction on paths that can be visualised as being on the surface of a torus: - If there is a difference between input and output angular velocities the motion has a component which is circular (i.e. round the rings formed by sections of the torus) - If the input and output stages have identical angular velocities there is no net centripetal force - and the motion of the fluid is circular and co-axial with the axis of rotation (i.e. round the edges of a torus), there is no flow of fluid from one turbine to the other. Stall speed An important characteristic of a fluid coupling is its stall speed. The stall speed is defined as the highest speed at which the pump can turn when the output turbine is locked and maximum input power is applied. Under stall conditions all of the engine's power would be dissipated in the fluid coupling as heat, possibly leading to damage. Step-circuit coupling A modification to the simple fluid coupling is the step-circuit coupling which was formerly manufactured as the "STC coupling" by the Fluidrive Engineering Company. The STC coupling contains a reservoir to which some, but not all, of the oil gravitates when the output shaft is stalled. This reduces the "drag" on the input shaft, resulting in reduced fuel consumption when idling and a reduction in the vehicle's tendency to "creep". When the output shaft begins to rotate, the oil is thrown out of the reservoir by centrifugal force, and returns to the main body of the coupling, so that normal power transmission is restored. Slip A fluid coupling cannot develop output torque when the input and output angular velocities are identical. Hence a fluid coupling cannot achieve 100 percent power transmission efficiency. Due to slippage that will occur in any fluid coupling under load, some power will always be lost in fluid friction and turbulence, and dissipated as heat. The very best efficiency a fluid coupling can achieve is 94 percent, that is for every 100 revolutions input, there will be 94 revolutions output. Like other fluid dynamical devices, its efficiency tends to increase gradually with increasing scale, as measured by the Reynolds number...
Просмотров: 172581 Jeff Quitney
Holograms, Holographs: "Introduction to Holography" 1972 Encyclopaedia Britannica Films
 
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more at http://scitech.quickfound.net/ "Examines the process of holography, types of holograms, and the uses of the hologram for artistic and scientific purposes." NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=ITk8nOFcxUE Public domain film slightly cropped to remove uneven edges, with the aspect ratio corrected, and 1-pass exposure & color correction applied (cannot be ideal in all scenes). The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Holography Holography (from the Greek ὅλος hólos, "whole" + γραφή grafē, "writing, drawing") is a technique which enables three-dimensional images to be made. It involves the use of a laser, interference, diffraction, light intensity recording and suitable illumination of the recording. The image changes as the position and orientation of the viewing system changes in exactly the same way as if the object were still present, thus making the image appear three-dimensional. The holographic recording itself is not an image; it consists of an apparently random structure of either varying intensity, density or profile... Overview and history The Hungarian-British physicist Dennis Gabor (Hungarian name: Gábor Dénes), was awarded the Nobel Prize in Physics in 1971 "for his invention and development of the holographic method". His work, done in the late 1940s, built on pioneering work in the field of X-ray microscopy by other scientists including Mieczysław Wolfke in 1920 and WL Bragg in 1939. The discovery was an unexpected result of research into improving electron microscopes at the British Thomson-Houston Company in Rugby, England, and the company filed a patent in December 1947 (patent GB685286). The technique as originally invented is still used in electron microscopy, where it is known as electron holography, but optical holography did not really advance until the development of the laser in 1960. The development of the laser enabled the first practical optical holograms that recorded 3D objects to be made in 1962 by Yuri Denisyuk in the Soviet Union and by Emmett Leith and Juris Upatnieks at University of Michigan, USA. Early holograms used silver halide photographic emulsions as the recording medium. They were not very efficient as the grating produced absorbed much of the incident light. Various methods of converting the variation in transmission to a variation in refractive index (known as "bleaching") were developed which enabled much more efficient holograms to be produced. Several types of holograms can be made. Transmission holograms, such as those produced by Leith and Upatnieks, are viewed by shining laser light through them and looking at the reconstructed image from the side of the hologram opposite the source. A later refinement, the "rainbow transmission" hologram, allows more convenient illumination by white light rather than by lasers... Another kind of common hologram, the reflection or Denisyuk hologram, can also be viewed using a white-light illumination source on the same side of the hologram as the viewer and is the type of hologram normally seen in holographic displays. They are also capable of multicolour-image reproduction. Specular holography is a related technique for making three-dimensional images by controlling the motion of specularities on a two-dimensional surface. It works by reflectively or refractively manipulating bundles of light rays, whereas Gabor-style holography works by diffractively reconstructing wavefronts. Most holograms produced are of static objects but systems for displaying changing scenes on a holographic volumetric display are now being developed. In its early days, holography required high-power expensive lasers, but nowadays, mass-produced low-cost semi-conductor or diode lasers, such as those found in millions of DVD recorders and used in other common applications, can be used to make holograms and have made holography much more accessible to low-budget researchers, artists and dedicated hobbyists. It was thought that it would be possible to use X-rays to make holograms of molecules and view them using visible light. However, X-ray holograms have not been created to date. How holography works Holography is a technique that enables a light field, which is generally the product of a light source scattered off objects, to be recorded and later reconstructed when the original light field is no longer present, due to the absence of the original objects. Holography can be thought of as somewhat similar to sound recording, whereby a sound field created by vibrating matter like musical instruments or vocal cords, is encoded in such a way that it can be reproduced later, without the presence of the original vibrating matter...
Просмотров: 117690 Jeff Quitney
Combat: "Kill Or Be Killed" 1943 War Department World War II US Army Training Film 10min
 
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NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=-tj2eE65yS4 more at http://quickfound.net/links/military_news_and_links.html "Fighting Men: Kill or Be Killed - Department of Defense. Department of the Army... This military training film shows that there are no rules of sportsmanship or fair play on the battlefield. As expressed in the film: 'Anything goes when the stakes are kill or be killed.' Soldiers were encouraged to use any weapon that comes to hand which could be anything from a rifle, to a bayonet or hand grenade." US Army training film TF21-1024 Public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization. http://en.wikipedia.org/wiki/Hand-to-hand_combat Hand-to-hand combat (sometimes abbreviated as HTH or H2H) is a lethal or nonlethal physical confrontation between two or more persons at very short range (grappling distance) that does not involve the use of firearms or other distance weapons. While the phrase "hand-to-hand" appears to refer to unarmed combat, the term is generic and may include use of striking weapons used at grappling distance such as knives, sticks, batons, or improvised weapons such as entrenching tools. While the term hand-to-hand combat originally referred principally to engagements by military personnel on the battlefield, it can also refer to any personal physical engagement by two or more combatants, including police officers and civilians. Combat within close quarters (to a range just beyond grappling distance) is commonly termed close combat or close-quarters combat. It may include lethal and nonlethal weapons and methods depending upon the restrictions imposed by civilian law, military rules of engagement, or personal ethical codes. Close combat using firearms or other distance weapons by military combatants at the tactical level is modernly referred to as close quarter battle. The U.S. Army uses the term combatives to describe various military martial art combat systems used in hand-to-hand combat training, systems which may incorporate hybrid techniques from several different martial arts and combat sports... Sometimes called close combat, Close Quarters Combat, or CQC, World War II-era American combatives were largely codified by William Ewart Fairbairn and Eric Anthony Sykes. Also known for their eponymous Fairbairn-Sykes fighting knife, Fairbairn and Sykes had worked in the Shanghai Municipal Police (SMP) and helped teach police officers as well as units of the U.S. Marine Corps and the Royal Marines a quick and effective and simple technique for fighting with or without weapons in melee situations. Similar training was provided to British Commandos, the Devil's Brigade, OSS, U.S. Army Rangers and Marine Raiders. Fairbairn at one point called this system Defendu, and later publishing an instructional training manual on the system. Defendu was later revised into a method of "quick kill" hand-to-hand combat training for soldiers by Fairbairn which he called "gutter fighting". The Fairbairn system was adopted and expanded by a U.S. military close combat instructor, Rex Applegate, for training U.S. military and paramilitary forces. Similar training was provided to British Commandos, the Devil's Brigade, OSS, U.S. Army Rangers and the Marine Raiders. Applegate would later describe this method of training in his own book, Kill or Get Killed. Other combat systems having their origins in military combat include European Unifight, Chinese Sanshou, Soviet/Russian sambo and Rukopaschnij Boj, Israeli Kapap and Krav Maga and Indian Bison System. The prevalence and style of hand-to-hand combat training often changes based on perceived need. Elite units such as special forces and commando units tend to place higher emphasis on hand-to-hand combat training. Although hand-to-hand fighting was accorded less importance in major militaries after World War II, insurgency conflicts such as the Vietnam War, low intensity conflict and urban warfare have prompted many armies to pay more attention to this form of combat. When such fighting includes firearms designed for close-in fighting, it is often referred to as Close Quarters Battle (CQB) at the platoon or squad level, or Military Operations on Urban Terrain (MOUT) at higher tactical levels...
Просмотров: 251586 Jeff Quitney
Orion Exploration Mission 1 Animation 2013 NASA
 
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more at http://scitech.quickfound.net/astro/orion_cev_news_and_links.html Public domain film from NASA. http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Exploration_Mission_1 Exploration Mission 1 or EM-1 (previously known as Space Launch System 1 or SLS-1) is the first planned flight of the Space Launch System and the second uncrewed test flight of the Orion Multi-Purpose Crew Vehicle. Set to launch on December 17, 2017 (later postponed to November 2018) from Launch Complex 39B at the Kennedy Space Center, the Orion spacecraft would perform a circumlunar trajectory during the seven day mission. The Block 1 version of SLS used on this mission will consist of two five-segment Solid Rocket Boosters, four RS-25D engines built for the Space Shuttle program and a Interim Cryogenic Propulsion Stage. EM-1 is intended to demonstrate the integrated spacecraft systems prior to a crewed flight and demonstrate a high speed reentry (11 km/s) on Orion's thermal protection system. On January 16, 2013, NASA announced that the European Space Agency would build Orion's service module based off of its Automated Transfer Vehicle, so the flight could also be regarded as a test of ESA hardware as well as American. http://www.nasa.gov/exploration/systems/sls/eft1_ksc.html ...The first SLS mission, Exploration Mission 1, in 2017 will launch an uncrewed Orion to demonstrate the integrated system performance of the SLS rocket and spacecraft prior to a crewed flight. The second SLS mission, Exploration Mission 2, is targeted for 2021 and will launch Orion and a crew of up to four American astronauts. The Orion Program is managed by NASA's Johnson Space Center in Houston. The SLS Program is managed by the Marshall Center. Both programs are managed by the Explorations Systems Development Division within the Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington. http://scitech.quickfound.net/astro/orion_cev_news_and_links.html Exploration is the name of the NASA directorate that has overall responsibility for developing new launch vehicles and spacecraft. The Lockheed Martin-built manned spacecraft component of the system, named the Orion Multi-Purpose Crew Vehicle (MPCV, formerly called the Crew Exploraton Vehicle, CEV), was originally intended to be operational by 2014 (with "boilerplate" tests by 2009 and unmanned flight tests of the actual vehicle by 2012), and to be capable of carrying astronauts to the moon by 2020. The first unmannned Orion test flight, Exploration Flight Test 1 (EFT-1), is now targeted for early 2014. Because the SLS Shuttle-replacement launch vehicle will not be ready until almost four years later, this test will ride on a Delta IV-Heavy launch vehicle. Tests of the Orion Boilerplate Test Article (BTA) began in 2011. Testing of the more advanced Orion Ground Test Article (GTA) are expected to begin at Langley Research Center in late 2012 or early 2013. Construction of the first Orion for unmanned orbital tests began in September, 2011. The SLS launch vehicle for Orion is not expected to fly until 2017 at the earliest...
Просмотров: 133333 Jeff Quitney
PreFab Homebuilding from Industry on Parade circa 1954 NAM, Prefabricated Housing
 
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more at http://hardware.quickfound.net/ National Homes Corporation, Lafayette, Indiana, makes the components of a full house every 7 minutes. From the National Association of Manufacturers "Industry on Parade" newsreel. Public domain film from the Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Prefabricated_building Prefabricated building is a type of building that consists of several factory-built components or units that are assembled on-site to complete the unit... History Buildings have been built in one place and reassembled in another throughout history. Possibly the first advertised prefab house was the Manning Portable Cottage. A London carpenter, Henry Manning, constructed a house that was built in components, then shipped and assembled by British emigrants. This was published at the time (advertisement, South Australian Record, 1837) and a few still stand in Australia. One such is the Friends Meeting House, Adelaide. The peak year for the importation of portable buildings to Australia was 1853, when several hundred arrived. These have been identified as coming from Liverpool, Boston and Singapore (with Chinese instructions for re-assembly). In Barbados the Chattel house was a form of prefabricated building which was developed by emancipated slaves who had limited rights to build upon land they did not own. As the buildings were moveable they were legally regarded as chattels. In 1855 during the Crimean War, after Florence Nightingale wrote a letter to The Times, Isambard Kingdom Brunel was commissioned to design a prefabricated modular hospital. In five months he designed a 1,000 patient hospital, with innovations in sanitation, ventilation and a flushing toilet. Fabricator William Eassie constructed the required 16 units in Gloucester Docks, shipped directly to the Dardanelles. Only used from March 1856 to September 1857, it reduced the death rate from 42% to 3.5%. The world's first prefabricated, pre-cast panelled apartment blocks were pioneered in Liverpool. A process was invented by city engineer John Alexander Brodie, whose inventive genius also had him inventing the football goal net. The tram stables at Walton in Liverpool followed in 1906. The idea was not extensively adopted in Britain, however was widely adopted elsewhere, particularly in Eastern Europe. Prefabricated homes were produced during the Gold Rush in the United States, when kits were produced to enable Californian prospectors to quickly construct accommodation. Homes were available in kit form by mail order in the United States in 1908. Prefabricated housing was popular during World War II due to the need for mass accommodation for military personnel. The United States used Quonset huts as military buildings, and in the United Kingdom prefabricated buildings used included Nissen huts and Bellman Hangars. 'Prefabs' were built after the war as a means of quickly and cheaply providing quality housing as a replacement for the housing destroyed during the war. The proliferation of prefabricated housing across the country was a result of the Burt Committee and the Housing (Temporary Accommodation) Act 1944. Under the Ministry of Works Emergency Factory Made housing programme, a specification was drawn up and bid on by various private construction and manufacturing companies. After approval by the MoW, companies could bid on Council led development schemes, resulting in whole estates of prefabs constructed to provide accommodation for those made homeless by the War and ongoing slum clearance. Almost 160,000 had been built in the UK by 1948 at a cost of close to £216 million. The largest single prefab estate in Britain was at Belle Vale (South Liverpool), where more than 1,100 were built after World War 2. The estate was demolished amid much controversy - the prefabs were very popular with residents - in the mid 1960s. Prefabs were aimed at families, and typically had an entrance hall, two bedrooms (parents and children), a bathroom (a room with a bath) — which was a novel innovation for many British at that time, a separate toilet, a living room and an equipped (not fitted in the modern sense) kitchen. Construction materials included steel, aluminium, timber or asbestos, depending on the type of dwelling. The aluminium Type B2 prefab was produced as four pre-assembled sections which could be transported by lorry anywhere in the country... http://en.wikipedia.org/wiki/Prefabricated_home http://en.wikipedia.org/wiki/Manufactured_housing
Просмотров: 19491 Jeff Quitney
Toxic Propellant Hazards ~ 1966 NASA KSC; Hydrazine Rocket Fuel & Nitrogen Tetroxide Oxidizer
 
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Chemistry playlist: https://www.youtube.com/playlist?list=PL_hX5wLdhf_KyuOalV6rwHjo810Zaa6xq NASA & Space Miscellany playlist: https://www.youtube.com/playlist?list=PL_hX5wLdhf_K3mK1TZNCkmdD-JMZYGew1 more at: http://scitech.quickfound.net NASA training film for workers handling hydrazine and nitrogen tetroxide at Kennedy Space Center and other NASA installations. "This NASA safety film demonstrates the dangers of rocket fuels, including hydrazine and nitrogen tetroxide, and instructs workers in their safe handling." Film produced by Technicolor, Inc. NASA film KSC-6. Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Hypergolic_propellant A hypergolic propellant combination used in a rocket engine is one whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. Although commonly used hypergolic propellants are difficult to handle because of their extreme toxicity and/or corrosiveness, they can be stored as liquids at room temperature and hypergolic engines are easy to ignite reliably and repeatedly. In contemporary usage, the terms "hypergol" or "hypergolic propellant" usually mean the most common such propellant combination, dinitrogen tetroxide plus hydrazine and/or its relatives monomethylhydrazine and unsymmetrical dimethylhydrazine... History Soviet rocket engine researcher Valentin Glushko experimented with hypergolic fuel as early as 1931. It was initially used for "chemical ignition" of engines, starting kerosene/nitric acid engines with an initial charge of phosphorus dissolved in carbon disulfide. Starting in 1935, Prof. O. Lutz of the German Aeronautical Institute experimented with over 1000 self-igniting propellants. He assisted the Walter Company with the development of C-Stoff which ignited with concentrated hydrogen peroxide... Hypergolic propellants were discovered independently, for the third time, in the U.S. by GALCIT and Navy Annapolis researchers in 1940. They developed engines powered by aniline and nitric acid. Robert Goddard, Reaction Motors and Curtiss-Wright worked on aniline/nitric acid engines in the early 1940s, for small missiles and jet assisted take-off (JATO)... Advantages Hypergolic rockets are usually simple and reliable because they need no ignition system... The most common hypergolic fuels, hydrazine, monomethylhydrazine and unsymmetrical dimethylhydrazine, and oxidizer, nitrogen tetroxide, are all liquid at ordinary temperatures and pressures. They are therefore sometimes called storable liquid propellants. They are suitable for use in spacecraft missions lasting many years... Because hypergolic rockets do not need an ignition system, they can fire any number of times by simply opening and closing the propellant valves until the propellants are exhausted and are therefore uniquely suited for spacecraft maneuvering... Disadvantages Relative to their mass, traditional hypergolic propellants are less energetic than such cryogenic propellant combinations as liquid hydrogen / liquid oxygen or liquid methane / liquid oxygen. A launch vehicle that uses hypergolic propellant must therefore carry a greater mass of fuel than one that uses these cryogenic fuels. The corrosivity, toxicity, and carcinogeneity of traditional hypergolics necessitate expensive safety precautions. Hypergolic combinations Common - Aerozine 50 + nitrogen tetroxide (N2O4) – widely used in historical American rockets, including the Titan 2; all engines in the Apollo Lunar Module; and the Service Propulsion System in the Apollo Service Module. Aerozine 50 is a mixture of 50% UDMH and 50% straight hydrazine (N2H4). - Unsymmetrical dimethylhydrazine (UDMH) + nitrogen tetroxide (N2O4) – frequently used by the Russians, such as in the Proton (rocket family) and supplied by them to France for the Ariane 1 first and second stages (replaced with UH 25); ISRO PSLV second stage. - UH 25 is a mixture of 25% hydrazine hydrate and 75% UDMH. - Monomethylhydrazine (MMH) + nitrogen tetroxide (NTO) – smaller engines and reaction control thrusters:[citation needed] Apollo Command Module reaction control system; Space Shuttle OMS and RCS; Ariane 5 EPS; Draco thrusters used by the SpaceX Dragon spacecraft. The corrosiveness of nitrogen tetroxide can be reduced by adding several percent nitric oxide (NO), forming mixed oxides of nitrogen (MON)...
Просмотров: 156814 Jeff Quitney
84 mph Truck Crash into 690 Ton Concrete Block: Nuclear Waste Cask Crash Tests 1978 DOE Sandia
 
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Nuclear & Radioactive playlist: https://www.youtube.com/playlist?list=PL4CD7F0970A5F16AB more at: http://scitech.quickfound.net Radioactive waste transportation safety tests conducted by Sandia National Laboratories in 1977 and 1978. A truck carrying a 22 ton nuclear waste flask (aka cask) crashes head on into a 690 ton concrete block at 60 miles per hour. After cleanup, the same cask is impacted into the block at 84 miles per hour. 3rd test: a locomotive crashes into a truck holding a 25 ton radioactive waste cask at 81 miles per hour. Final test: a 74 ton nuclear waste cask aboard a cask rail car impacts the concrete block at 81 mph, then is burned by a pool of jet fuel for 90 minutes, during which temps exceeded 1400 degrees F. What is not mentioned is the possibility of a nuclear waste cask truck impacting another truck traveling at 60+ mph in the opposite direction making the combined velocity 120+ mph. Public domain film slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Nuclear_flask A nuclear flask is a shipping container that is used to transport active nuclear materials between nuclear power station and spent fuel reprocessing facilities. Each shipping container is designed to maintain its integrity under normal transportation conditions and during hypothetical accident conditions. They must protect their contents against damage from the outside world, such as impact or fire. They must also contain their contents from leakage, both for physical leakage and for radiological shielding. Spent nuclear fuel shipping casks are used to transport spent nuclear fuel used in nuclear power plants and research reactors to disposal sites such as the nuclear reprocessing center at COGEMA La Hague site... In the United States, the acceptability of the design of each cask is judged against Title 10, Part 71, of the Code of Federal Regulations (other nations' shipping casks, possibly excluding Russia's, are designed and tested to similar standards (International Atomic Energy Agency "Regulations for the Safe Transport of Radioactive Material" No. TS-R-1)). The designs must demonstrate (possibly by computer modelling) protection against radiological release to the environment under all four of the following hypothetical accident conditions, designed to encompass 99% of all accidents: - A 9-meter (30 ft) free fall onto an unyielding surface - A puncture test allowing the container to free-fall 1 meter (about 39 inches) onto a steel rod 15 centimeters (about 6 inches) in diameter - A 30-minute, all-engulfing fire at 800 degrees Celsius (1475 degrees Fahrenheit) - An 8-hour immersion under 0.9 meter (3 ft) of water. - Further, an undamaged package must be subjected to a one-hour immersion under 200 meters (655 ft) of water. In addition, between 1975 and 1977 Sandia National Laboratories conducted full-scale crash tests on spent nuclear fuel shipping casks. Although the casks were damaged, none would have leaked... Since 1965, approximately 3,000 shipments of spent nuclear fuel have been transported safely over the U.S.'s highways, waterways, and railroads. Baltimore train tunnel fire On July 18, 2001, a freight train carrying hazardous (non-nuclear) materials derailed and caught fire while passing through the Howard Street railroad tunnel in downtown Baltimore, Maryland, United States. The fire burned for 3 days, with temperatures as high as 1000 °C (1800 °F). Since the casks are designed for a 30-minute fire at 800 °C (1475 °F), several reports have been made regarding the inability of the casks to survive... State of Nevada The State of Nevada, USA, released a report entitled, "Implications of the Baltimore Rail Tunnel Fire for Full-Scale Testing of Shipping Casks" on February 25, 2003. In the report, they said a hypothetical spent nuclear fuel accident based on the Baltimore fire: - "Concluded steel-lead-steel cask would have failed after 6.3 hours; monolithic steel cask would have failed after 11-12.5 hours." - "Contaminated Area: 32 square miles (82 km2)" - "Latent cancer fatalities: 4,000-28,000 over 50 years (200-1,400 during first year)" - "Cleanup cost: $13.7 Billion (2001 Dollars)"...
Просмотров: 387890 Jeff Quitney
Fallout: When And How To Protect Yourself 1959 U S Office Of Civil Defense
 
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more at http://scitech.quickfound.net/ "Illustrates the cause and effects of radioactive fallout. Describes preparations which should be made to safeguard lives and protect food and water supplies. Animated." Public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Fallout_shelter A fallout shelter is an enclosed space specially designed to protect occupants from radioactive debris or fallout resulting from a nuclear explosion. Many such shelters were constructed as civil defense measures during the Cold War. During a nuclear explosion, matter vaporized in the resulting fireball is exposed to neutrons from the explosion, absorbs them, and becomes radioactive. When this material condenses in the rain, it forms dust and light sandy materials that resembles ground pumice. The fallout emits alpha and beta particles, as well as gamma rays. Much of this highly radioactive material then falls to earth, subjecting anything within the line of sight to radiation, a significant hazard. A fallout shelter is designed to allow its occupants to minimize exposure to harmful fallout until radioactivity has decayed to a safer level. Although many shelters still exist, many even being used as museums, virtually all fallout shelters have been decommissioned since the fall of the Soviet Union in 1991... Shielding A basic fallout shelter consists of shields that reduce gamma ray exposure by a factor of 1000. The required shielding can be accomplished with 10 times the amount of any quantity of material capable of cutting gamma ray effects in half. Shields that reduce gamma ray intensity by 50% (1/2) include 1 cm (0.4 inch) of lead, 6 cm (2.4 inches) of concrete, 9 cm (3.6 inches) of packed dirt or 150 m (500 ft) of air. When multiple thicknesses are built, the shielding multiplies. Thus, a practical fallout shield is ten halving-thicknesses of packed dirt, reducing gamma rays by 1024 times. Usually, an expedient purpose-built fallout shelter is a trench; with a strong roof buried by c. 1 m (3 ft) of dirt. The two ends of the trench have ramps or entrances at right angles to the trench, so that gamma rays cannot enter (they can travel only in straight lines). To make the overburden waterproof (in case of rain), a plastic sheet should be buried a few inches below the surface and held down with rocks or bricks. Blast doors are designed to absorb the shock wave of a nuclear blast, bending and then returning to their original shape. Climate control Dry earth is a reasonably good thermal insulator, and over several weeks of habitation, a shelter will become too hot for comfort. The simplest form of effective fan to cool a shelter is a wide, heavy frame with flaps that swing in the shelter's doorway and can be swung from hinges on the ceiling. The flaps open in one direction and close in the other, pumping air. Attach a rope, and take turns swinging it. (This is a Kearny Air Pump, or KAP, named after the inventor.) Unfiltered air is safe, since the most dangerous fallout has the consistency of sand or finely ground pumice. Such large particles are not easily ingested into the soft tissues of the body, so extensive filters are not required. Any exposure to fine dust is far less hazardous than exposure to the gamma from the fallout outside the shelter. Dust fine enough to pass the entrance will probably pass through the shelter. Collective NBC protection system Usually blast protection valves are installed at the air-inlet and air outlet to prevent the penetration of blast waves caused by explosions outside of the shelter. A positive pressure (overpressure) is created in the shelter by pulling filtered air into the protected area. The air is filtered by the means of NBC-filters (NBC = Nuclear, Biological and Chemical filters)...
Просмотров: 108493 Jeff Quitney
B-52 Flying Without a Tail: "Flight Without a Fin" 1964 US Air Force
 
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more at http://scitech.quickfound.net/aviation_news_and_search.html A B-52 flying over Colorado on January 10, 1964 lost its vertical stabilizer due to clear-air turbulence, but made it to a safe landing. NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=XDi5mippaxQ USAF film FR-479 Public domain film from the United States Air Force, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://www.boeing.com/defense-space/military/b52-strat/b52_50th/story3.htm January 10, 1964, started out as a typical day for the flight test group at Boeing's Wichita plant. Pilot Chuck Fisher took off in a B-52H with a three-man Boeing crew, flying a low-level profile to obtain structural data. Over Colorado, cruising 500 feet above the mountainous terrain, the B-52 encountered some turbulence. Fisher climbed to 14,300 feet looking for smoother air. At this point the typical day ended.The bomber flew into clear-air turbulence. It felt as if the plane had been placed in a giant high-speed elevator, shoved up and down, and hit by a heavy blow on its right side. Fisher told the crew to prepare to abandon the plane. He slowed the aircraft and dropped to about 5,000 feet to make it easier to bail out. But then Fisher regained some control. He climbed slowly to 16,000 feet to put some safety room between the plane and the ground. He informed Wichita about what was happening. Although control was difficult, Fisher said he believed he could get the plane back in one piece. Response to the situation at Wichita, and elsewhere, was immediate. An emergency control center was set up in the office of Wichita's director of flight test. Key Boeing engineers and other specialists were summoned to provide their expertise. Federal Aviation Administration air traffic control centers at Denver and Kansas City cleared the air around the troubled plane. A Strategic Air Command B-52 in the area maintained radio contact with the crew of the Wichita B-52. As Fisher got closer to Wichita, a Boeing chase plane flew up to meet him and to visually report the damage. When Dale Felix, flying an F-100 fighter, came alongside Fisher's B-52, he couldn't believe what he saw: The B-52's vertical tail was gone. Felix broke the news to Fisher and those gathered in the control center. There was no panic. Everyone on the plane and in the control center knew they could be called upon at any time for just such a situation. In the emergency control center, the engineers began making calculations and suggesting the best way to get the plane down safely. The Air Force was also lending assistance. A B-52, just taking off for a routine flight, was used to test the various flight configurations suggested by the specialists before Fisher had to try them. As high gusty winds rolled into Wichita, the decision was made to divert the B-52 to Blytheville Air Force Base in Northeastern Arkansas. Boeing specialists from the emergency control center took off in a KC-135 and accompanied Fisher to Blytheville, serving as an airborne control center. Six hours after the incident first occurred, Fisher and his crew brought in the damaged B-52 for a safe landing. "I'm very proud of this crew and this airplane," Fisher said. "Also we had a lot people helping us, and we're very thankful for that." The B-52, Fisher said, "Is the finest airplane I ever flew." http://en.wikipedia.org/wiki/Boeing_B-52_Stratofortress Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ The Boeing B-52 Stratofortress is a long-range, subsonic, jet-powered strategic bomber. The B-52 was designed and built by Boeing,... Beginning with the successful contract bid in June 1946, the B-52 design evolved from a straight-wing aircraft powered by six turboprop engines to the final prototype YB-52 with eight turbojet engines and swept wings. The B-52 took its maiden flight in April 1952. Built to carry nuclear weapons for Cold War-era deterrence missions, the B-52 Stratofortress replaced the Convair B-36... The B-52 has been in active service with the USAF since 1955. As of 2012, 85 remain in service with 9 in reserve. The bombers flew under the Strategic Air Command (SAC) until it was disestablished in 1992 and its aircraft absorbed into the Air Combat Command (ACC); in 2010 all B-52 Stratofortresses were transferred from the ACC to the new Air Force Global Strike Command (AFGSC)... The B-52 marked its 50th anniversary of continuous service with its original operator in 2005 and after being upgraded between 2013 and 2015 it will serve into the 2040s...
Просмотров: 422425 Jeff Quitney
Motion Picture Persistence of Vision: "How You See It" 1936 Chevrolet 8min
 
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more at http://showbiz.quickfound.net/ "How persistence of vision makes motion pictures possible." NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=-pHXsSEaQ10 Public domain film from the Library of Congress Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Persistence_of_vision Persistence of vision is the phenomenon of the eye by which an afterimage is thought to persist for approximately one twenty-fifth of a second on the retina. The myth of persistence of vision is the belief that human perception of motion (brain centered) is the result of persistence of vision (eye centred). The myth was debunked in 1912 by Wertheimer but persists in many citations in many classic and modern film-theory texts. A more plausible theory to explain motion perception (at least on a descriptive level) are two distinct perceptual illusions: phi phenomenon and beta movement. A visual form of memory known as iconic memory has been described as the cause of this phenomenon. Although psychologists and physiologists have rejected the relevance of this theory to film viewership, film academics and theorists generally have not. Some scientists nowadays consider the entire theory a myth. In contrasting persistence of vision theory with phi phenomena, a critical part of understanding that emerges with these visual perception phenomena is that the eye is not a camera. In other words vision is not as simple as light registering on a medium, since the brain has to make sense of the visual data the eye provides and construct a coherent picture of reality. Joseph Anderson and Barbara Fisher argue that the phi phenomena privileges a more constructionist approach to the cinema (David Bordwell, Noël Carroll, Kirsten Thompson), whereas the persistence of vision privileges a realist approach (André Bazin, Christian Metz, Jean-Louis Baudry). The discovery of persistence of vision is attributed to the Roman poet Lucretius, although he only mentions it in connection with images seen in a dream. In the modern era, some stroboscopic experiments performed by Peter Mark Roget in 1824 were also cited as the basis for the theory. Film systems Persistence of vision is still the accepted term for this phenomenon in the realm of cinema history and theory. In the early days of film innovation, it was scientifically determined that a frame rate of less than 16 frames per second (frame/s) caused the mind to see flashing images. Audiences still interpret motion at rates as low as ten frames per second or slower (as in a flipbook), but the flicker caused by the shutter of a film projector is distracting below the 16-frame threshold. Modern theatrical film runs at 24 frames a second. This is the case for both physical film and digital cinema systems. It is important to distinguish between the frame rate and the flicker rate, which are not necessarily the same. In physical film systems, it is necessary to pull down the film frame, and this pulling-down needs to be obscured by a shutter to avoid the appearance of blurring; therefore, there needs to be at least one flicker per frame in film. To reduce the appearance of flicker, virtually all modern projector shutters are designed to add additional flicker periods, typically doubling the flicker rate to 48 Hz (single-bladed shutters make two rotations per frame -- double-bladed shutters make one rotation per frame), which is less visible. (Some three-bladed projector shutters even triple it to 72 Hz.) In digital film systems, the scan rate may be decoupled from the image update rate. In some systems, such as the Digital Light Processing (DLP) system, there is no flying spot or raster scan at all, so there is no flicker other than that generated by the temporal aliasing of the film image capture. The new film system MaxiVision 48 films at 48 frames per second, which, according to film critic Roger Ebert, offers even a strobeless tracking shot past picket fences. The lack of strobe (as opposed to flicker) is due to the higher sampling rate of the camera relative to the speed of movement of the image across the film plane. This ultra-smooth imaging is called High motion. It is critical for sports and motion simulation, but unpopular for drama...
Просмотров: 52956 Jeff Quitney
Logging Giant Redwood Trees: "Redwood Saga" 1946; How Trees Were Logged in Northern California
 
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Forestry, Logging, Wood, Lumber, Sawmills, Lumberjacks... playlist: https://www.youtube.com/playlist?list=PL_hX5wLdhf_ItHl6u0oUCHbUyb7KlUpup Biosphere - Plants & Animals playlist: https://www.youtube.com/playlist?list=PL1FCE267E4A977761 more at http://scitech.quickfound.net/environment/environment_news.html "Cutting, loading, transportation, mill sawing and finishing operations of the Northern California's redwood lumber industry." Reupload of a previously uploaded film with improved video & sound. Public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Logging_in_the_Sierra_Nevada Logging in the Californian Sierra Nevada arose from the need to support growing communities in the area. The Gold Rush created a high demand for timber to build housing, for mining procedures, and especially to build railroads. In these days use was unregulated and in the first 20 years after the rush, a third of the timber in the Sierra Nevada was logged . Concern for the forests created a movement towards conservation at the turn of the 19th century creating state and national parks (Yosemite, Sequoia and Grant Grove) and forest reserves. The Sierra Club, a non-governmental organization (NGO), was founded around this time by the famous preservationist John Muir. Between 1900 and 1940 agencies like the U.S. Forest Service and The National Park Service regulated the use of the Sierra Nevada's resources. The economy boom after World War II dramatically increased timber production in the Sierras using clear-cutting as the dominant form of logging. Methods One method of logging is clear-cutting, removing all trees from a tract of land, which has caused major disturbances in the Sierra Nevada environment leaving patches of densely packed, single-specie, same-aged, tree plantations among the diverse old growth forest. Low-impact logging meets current needs without compromising the ability of future generations to meet their needs. This typically means smaller periodic harvests and removing the worst trees to eliminate danger to high value trees... Environmental effects Logging practices have altered the majority of the native forests, transforming them into simplified forests of same-aged trees with a reduced ecological resilience[citation needed]. These disturbed stands are especially prone to catastrophic fire and mortality due to beetle infestation and disease. It has also caused fragmentation and increased edge effect, along with releasing pesticides and chemicals into the water and land. In the Sierra's there are 218 endemic plant species that are considered rare or threatened, and three plant species are believed to be extinct. Sixty-nine terrestrial vertebrate species are considered at risk by government agencies... http://en.wikipedia.org/wiki/Logging http://en.wikipedia.org/wiki/Sequoia_sempervirens Sequoia sempervirens is the sole living species of the genus Sequoia in the cypress family Cupressaceae (formerly treated in Taxodiaceae). Common names include coast redwood, California redwood, and giant redwood. It is an evergreen, long-lived, monoecious tree living 1200--1800 years or more. This species includes the tallest trees on Earth, reaching up to 379 feet (115.5 m) in height (without the roots) and up to 26 feet (7.9 m) in diameter at breast height. Before commercial logging and clearing began by the 1850s, this massive tree occurred naturally in an estimated 2,100,000 acres (8,500 km2) along much of coastal California (excluding southern California where rainfall is not sufficient) and the southwestern corner of coastal Oregon within the United States. It is estimated that more than 95% of the original old-growth redwood forest has been cut down, due to its excellent properties for use as lumber in construction. The name sequoia sometimes refers to the subfamily Sequoioideae, which includes S. sempervirens along with Sequoiadendron (giant sequoia) and Metasequoia (dawn redwood). On its own, the term redwood usually refers to the coast redwood, which is covered in this article, and not to the other two species... Although coast redwoods are currently the world's tallest trees, it is possible that Australian mountain ash and Douglas-fir trees were taller—exceeding 400 feet (120 m)—before the commercial logging of the 19th and 20th centuries... There is fairly solid evidence that before logging, coast redwoods were the world's largest trees, with specimens measured at over 55,000 cubic feet (1,600 m3) (660,000 board feet)...
Просмотров: 18862 Jeff Quitney
M14 Rifle Marksmanship: "The Rifle" United States Marine Corps Training Film circa 1960s
 
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NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=O2AfDmKopsQ more at http://quickfound.net/links/military_news_and_links.html "A US Marine Corps Training film from the 1960s that covers the basics of marksmanship and rifle care and maintenance." Public domain film slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/M14_rifle M14 rifle, formally the United States Rifle, 7.62 mm, M14, is an American selective fire automatic rifle firing 7.62×51mm NATO (.308 Winchester) ammunition. It was the standard issue U.S. rifle from 1959 to 1970. The M14 rifle was used for U.S. Army and Marine Corps basic and advanced individual training, and was the standard issue infantry rifle for U.S. military personnel in the Contiguous United States, Europe, and South Korea, until it was replaced by the M16 rifle, in 1970. The M14 rifle remains in limited front line service within all branches of the U.S. military, and is also used as a ceremonial weapon by honor guards, color guards, drill teams, ceremonial guards, and the like. The M14 rifle was also the last American "battle rifle" (a term applied to weapons firing full-power rifle ammunition, such as the 7.62mm cartridge) issued in quantity to U.S. military personnel. The M14 rifle also provides the basis for the M21 and M25 sniper rifles... Early development The M14 was developed from a long line of experimental weapons based upon the M1 rifle. Although the M1 was among the most advanced infantry rifles of the late 1930s, it was not a perfect weapon. Modifications were beginning to be made to the basic M1 rifle's design since the twilight of World War II. Changes included adding fully automatic firing capability and replacing the 8-round en bloc clips with a detachable box magazine holding 20 rounds. Winchester, Remington, and Springfield Armory's own John Garand offered different conversions. Garand's design, the T20, was the most popular, and T20 prototypes served as the basis for a number of Springfield test rifles from 1945 through the early 1950s. In 1945, Earle Harvey of Springfield Armory designed a completely different rifle, the T25, for the new T65 .30 Light Rifle cartridge at the direction of Col. Rene Studler, then serving in the Pentagon. In late 1945 the two men were transferred to Springfield Armory, where work on the T25 continued. The T-25 was designed to use the T65 service cartridge, a Frankford Arsenal design based upon .30-06 cartridge case used in the M1 service rifle, but shortened to the length of the .300 Savage case. Although shorter than the .30-06, with less powder capacity, the T65 cartridge retained the ballistics and energy of the .30-06 due to the use of a recently developed ball powder made by Olin Industries. After experimenting with several bullet designs, the T65 was finalized for adoption as the 7.62x51mm NATO cartridge. Olin Industries later marketed the cartridge on the commercial market as the commercial .308 Winchester round. After a series of revisions by Earle Harvey and other members of the .30 Light Rifle design group following the 1950 Ft. Benning tests, the T25 was renamed the T47. In contrast, the T44 prototype service rifle was not principally designed by any single engineer at Springfield Armory, but rather was a conventional design developed on a shoestring budget as an alternative to the T47. With only minimal funds available, the earliest T44 prototypes simply used T20E2 receivers fitted with magazine filler blocks and re-barreled for 7.62mm NATO, with the long operating rod/piston of the M1 replaced by the T47's gas cut-off system. Lloyd Corbett, an engineer in Earle Harvey's rifle design group, added various refinements to the T44 design, including a straight operating rod and a bolt roller to reduce friction... In June 1954, funding was finally made available to manufacture newly fabricated T44 receivers specially designed for the shorter T65 cartridge. This one change to the T44 design saved a pound in rifle weight over that of the M1 Garand. Tests at Ft. Benning with the T44 and T48 continued through the summer and fall of 1956. By this time, the T48/FAL rifles had been so improved that malfunction rates were almost as low as the T44. In the end, the T44 was selected over the T48/FAL primarily because of weight (the T44 was a pound lighter than the T48), simplicity (the T44 had fewer parts), the T44's self-compensating gas system, and the argument that the T44 could be manufactured on existing machinery built for the M1 rifle (a concept that later turned out to be unworkable). In 1957, the U.S. formally adopted the T44 as the U.S. infantry service rifle, designated M14...
Просмотров: 209515 Jeff Quitney
How to Use Tools: "Fundamentals Of Filing" 1942 US Office of Education
 
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Metals playlist: https://www.youtube.com/playlist?list=PL64F10A579EB0A526 Vocations, Jobs, Industrial Arts playlist: https://www.youtube.com/playlist?list=PLEAE22DC3E1D959BE Machine Shop Work: Bench Work No. 8: Fundamentals of Filing "Gives beginners in shop work the information that will enable them to select the right file for the right job. Defines the terms used, distinguishes the various kinds of files, and indicates the general type of work that each kind of file does best." Public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/File_(tool) A file is a tool used to remove fine amounts of material from a workpiece. It is common in woodworking, metalworking, and other similar trade and hobby tasks. Most are hand tools, made of a case hardened steel bar of rectangular, square, triangular, or round cross-section, with one or or more surfaces cut with sharp, generally parallel teeth. A narrow, pointed tang is common at one end, to which a handle may be fitted. A rasp is a form of file with distinct, individually cut teeth used for coarsely removing large amounts of material. Files have also been developed with abrasive surfaces, such as natural or synthetic diamond grains or silicon carbide, allowing removal of material that would dull or resist metal, such as ceramic... History Early filing or rasping... has prehistoric roots and grew naturally out of the blending of the twin inspirations of cutting with stone cutting tools (such as hand axes) and abrading using natural abrasives, such as well-suited types of stone (for example, sandstone). Relatedly, lapping is also quite ancient, with wood and beach sand offering a natural pair of lap and lapping compound... The Bronze Age and the Iron Age had various kinds of files and rasps. Archaeologists have discovered rasps made from bronze in Egypt, dating back to the years 1200–1000 BC... During the Middle Ages files were already quite advanced, thanks to the extensive talents of blacksmiths. By the 11th century, there already existed hardened files that would seem quite modern even to today's eyes. But although they existed, and could even have spread widely, in a geographical sense, via trade, they were not widespread in the cultural sense of the word—that is, most people, and even many smiths, did not have them. For example, in the 13th century, ornamental iron work at Paris was done skillfully with the aid of files, but the process was a secret known only to a master craftsman... Prior to the industrialization of machining and the development of interchangeable parts during the 19th century, filing was much more important in the construction of mechanisms. Component parts were roughly shaped by forging, casting, and by primitive machining operations. These components were then individually hand-fit for assembly by careful and deliberate filing. The potential precision of such fitting is much higher than generally assumed, but the components of such hand-fit assemblies are decidedly not interchangeable with those from another assembly... Machining in the mid-19th century was heavily dependent on filing, because milling practice was slowly evolving out of its infancy. As late as the early 20th century, manufacturing often involved filing parts to precise shape and size. In today's manufacturing environment, milling and grinding have generally replaced this type of work, and filing (when it occurs at all) usually tends to be for deburring only... Files come in a wide variety of materials, sizes, shapes, cuts, and tooth configurations. The cross-section of a file can be flat, round, half-round, triangular, square, knife edge or of a more specialized shape. Steel files are made from high carbon steel (1.0 to 1.25% carbon) and may be through hardened or case hardened. ...A file is "blunt" if its sides and width are both parallel throughout its length. It is "tapered" if there is a reduction in its dimensions from its heel toward its point. A file may taper in width, in thickness, or both. A "tang" is a protrusion at the heel, tapered, parallel sided, or conical, for gripping, inserting in a handle, or mounting in a chuck. The cut of the file refers to how fine its teeth are. They are defined as (from roughest to smoothest): rough, middle, bastard, second cut, smooth, and dead smooth. A single-cut file has one set of parallel teeth while a cross-cut or double-cut file has a second set of cuts forming diamond shaped cutting surfaces...
Просмотров: 36133 Jeff Quitney
Electronics: Introduction to LC Oscillators circa 1974 US Air Force Training Film
 
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more at: http://scitech.quickfound.net "In an LC oscillator circuit, the filter is a tuned circuit consisting of an inductor (L) and capacitor (C) connected together." US Air Force Training Film TVK 30-536 Electronics playlist: https://www.youtube.com/playlist?list=PLAA9B0175C3E15B47 Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Electronic_oscillator An electronic oscillator is an electronic circuit that produces a periodic, oscillating electronic signal, often a sine wave or a square wave. Oscillators convert direct current (DC) from a power supply to an alternating current signal. They are widely used in many electronic devices. Common examples of signals generated by oscillators include signals broadcast by radio and television transmitters, clock signals that regulate computers and quartz clocks, and the sounds produced by electronic beepers and video games. Oscillators are often characterized by the frequency of their output signal: A low-frequency oscillator (LFO) is an electronic oscillator that generates a frequency below ≈20 Hz. This term is typically used in the field of audio synthesizers, to distinguish it from an audio frequency oscillator. An audio oscillator produces frequencies in the audio range, about 16 Hz to 20 kHz. An RF oscillator produces signals in the radio frequency (RF) range of about 100 kHz to 100 GHz. Oscillators designed to produce a high-power AC output from a DC supply are usually called inverters. There are two main types of electronic oscillator: the linear or harmonic oscillator and the nonlinear or relaxation oscillator... Harmonic oscillator The harmonic, or linear, oscillator produces a sinusoidal output. There are two types: Feedback oscillator The most common form of linear oscillator is an electronic amplifier such as a transistor or op amp connected in a feedback loop with its output fed back into its input through a frequency selective electronic filter to provide positive feedback. When the power supply to the amplifier is first switched on, electronic noise in the circuit provides a signal to get oscillations started. The noise travels around the loop and is amplified and filtered until very quickly it becomes a sine wave at a single frequency. Feedback oscillator circuits can be classified according to the type of frequency selective filter they use in the feedback loop: In an RC oscillator circuit, the filter is a network of resistors and capacitors. RC oscillators are mostly used to generate lower frequencies, for example in the audio range. Common types of RC oscillator circuits are the phase shift oscillator and the Wien bridge oscillator. In an LC oscillator circuit, the filter is a tuned circuit (often called a tank circuit; the tuned circuit is a resonator) consisting of an inductor (L) and capacitor (C) connected together. Charge flows back and forth between the capacitor's plates through the inductor, so the tuned circuit can store electrical energy oscillating at its resonant frequency. There are small losses in the tank circuit, but the amplifier compensates for those losses and supplies the power for the output signal. LC oscillators are often used at radio frequencies, when a tunable frequency source is necessary, such as in signal generators, tunable radio transmitters and the local oscillators in radio receivers. Typical LC oscillator circuits are the Hartley, Colpitts and Clapp circuits. In a crystal oscillator circuit the filter is a piezoelectric crystal (commonly a quartz crystal). The crystal mechanically vibrates as a resonator, and its frequency of vibration determines the oscillation frequency. Crystals have very high Q-factor and also better temperature stability than tuned circuits, so crystal oscillators have much better frequency stability than LC or RC oscillators. Crystal oscillators are the most common type of linear oscillator, used to stabilize the frequency of most radio transmitters, and to generate the clock signal in computers and quartz clocks. Crystal oscillators often use the same circuits as LC oscillators, with the crystal replacing the tuned circuit; the Pierce oscillator circuit is also commonly used. Quartz crystals are generally limited to frequencies of 30 MHz or below. Other types of resonator, dielectric resonators and surface acoustic wave (SAW) devices, are used to control higher frequency oscillators, up into the microwave range. For example, SAW oscillators are used to generate the radio signal in cell phones...
Просмотров: 173752 Jeff Quitney
Tropospheric Scatter Communication Site in Germany 1967 US Army; Meteor Burst Communications
 
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Shortwave & Military Radio playlist: https://www.youtube.com/playlist?list=PLA4AC5A9478CECACC more at http://scitech.quickfound.net In the Black Forest region near Feldberg, Germany: Company A, 68th Signal Battalion conducts worldwide communications using four 30-foot parabolic antennas atop a 160-foot tall tower. They are supplied by H-19 helicopter. From "Your Army Reports" No. 10; "The Big Picture" TV-713. Reupload of a previously uploaded film with improved video & sound. Originally a public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://en.wikipedia.org/wiki/Meteor_burst_communications Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ Meteor burst communications (MBC), also referred to as meteor scatter communications, is a radio propagation mode that exploits the ionized trails of meteors during atmospheric entry to establish brief communications paths between radio stations up to 2,250 kilometres (1,400 mi) apart... How it works As the earth moves along its orbital path, billions of particles known as meteors enter the earth's atmosphere every day; a small fraction of which have properties useful for point to point communication. When these meteors begin to burn up, they create a trail of ionized particles in the E layer of the atmosphere that can persist for up to several seconds. The ionization trails can be very dense and thus used to reflect radio waves. The frequencies that can be reflected by any particular ion trail are determined by the intensity of the ionization created by the meteor, often a function of the initial size of the particle, and are generally between 30 MHz and 50 MHz. The distance over which communications can be established is determined by the altitude at which the ionization is created, the location over the surface of the Earth where the meteor is falling, the angle of entry into the atmosphere, and the relative locations of the stations attempting to establish communications. Because these ionization trails only exist for fractions of a second to as long as a few seconds in duration, they create only brief windows of opportunity for communications. Military use One of the first major deployments was "COMET" (COmmunication by MEteor Trails), used for long-range communications with NATO's Supreme Headquarters Allied Powers Europe headquarters. COMET became operational in 1965, with stations located in the Netherlands, France, Italy, West Germany, the United Kingdom, and Norway.[citation needed] COMET maintained an average throughput between 115 and 310 bits per second, depending on the time of year. Meteor burst communications faded from interest with the increasing use of satellite communications systems starting in the late 1960s. However, in the late 1970s it became clear that the satellites were not as universally useful as originally thought, notably at high latitudes or where signal security was an issue. For these reasons, the U.S. Air Force installed the Alaska Air Command MBC system in the 1970s, although it is not publicly known whether this system is still operational. A more recent study is the Advanced Meteor Burst Communications System (AMBCS), a testbed set up by SAIC under DARPA funding. Using phase-steerable antennas directed at the proper area of the sky for any given time of day, the direction where the Earth is moving "forward", AMBCS was able to greatly improve the data rates, averaging 4 kilobits per second (kbit/s). While satellites may have a nominal throughput about 14 times greater, they're vastly more expensive to operate. Additional gains in throughput are theoretically possible through the use of real-time steering. The basic concept is to use backscattered signals to pinpoint the exact location of the ion trail and direct the antenna to that spot, or, in some cases, several trails at once. This improves the gain, allowing for much improved data rates. To date, this approach has not been tried experimentally, so far as is known. Scientific use The United States Department of Agriculture (USDA) uses meteor scatter extensively in its SNOTEL system. Over 800 snow water content gauging stations in the Western United States are equipped with radio transmitters that rely upon meteor scatter communications to send measurements to a data center. The snow depth data collected by this system can be viewed on the Internet. In Alaska, a similar system is used in the Alaskan Meteor Burst Communications System (AMBCS), collecting data for the National Weather Service from automated weather stations, as well as occasional data from other US government agencies.
Просмотров: 4948 Jeff Quitney
Coney Island: America at Play 1918 Ford Educational Pictures. JQ Music
 
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more at http://news.quickfound.net/cities/new_york_city.html Good early look at Coney Island fun. The film was silent. I have added music created by myself using the Reaper Digital Audio Workstation and the Independence and Proteus VX VST instrument plugins. Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Coney_Island Coney Island is a peninsular residential neighborhood, beach and attraction destination on the Atlantic Ocean in southwestern Brooklyn, New York City. The site was formerly an outer barrier island, but became partially connected to the mainland by landfill. The residential portion of the peninsula is a community of 60,000 people in its western part, with Sea Gate to its west, Brighton Beach and Manhattan Beach to its east, and Gravesend to the north. Coney Island is well known as the site of amusement parks and a seaside resort. The attractions reached a historical peak during the first half of the 20th century, declining in popularity after World War II and years of neglect. In recent years, the area has seen the opening of MCU Park stadium and has become home to the Brooklyn Cyclones minor league baseball team, as well as the opening of a new amusement park among several adjacent ones... Due to Coney Island's location—easily reached from Manhattan and other boroughs of New York City, yet distant enough to suggest a proper vacation—it began attracting holidaymakers in the 1830s and 1840s, when carriage roads and steamship services reduced travel time from a half-day journey to just two hours. The original Coney Island Hotel was constructed in 1829, with The Brighton Hotel, Manhattan Beach Hotel, and Oriental Hotel opening soon after, with each trying to provide an increasing level of elegance. Coney Island became a major resort destination after the American Civil War, as excursion railroads and the Coney Island & Brooklyn Railroad streetcar line reached the area in the 1860s, and the Iron steamboat company arrived in 1881. The two Iron Piers served as docks for the steamboats until they were destroyed in the 1911 Dreamland fire. When the Brooklyn Rapid Transit Company electrified the steam railroads and connected Brooklyn to Manhattan via the Brooklyn Bridge at the beginning of the 20th century, Coney Island soon turned from a resort to a location accessible to day-trippers from New York City, especially those escaping the summer heat. Charles I. D. Looff, a Danish woodcarver, built the first carousel at Coney Island in 1876. It was installed at Vandeveer's bath-house complex at West 6th Street and Surf Avenue, which later became known as Balmer's Pavilion. The carousel consisted of hand-carved horses and other animals standing two abreast, with a drummer and a flute player providing the music. A tent-top provided protection from the weather. The fare was five cents. From 1885 to 1896, the Coney Island Elephant was the first sight to greet immigrants arriving in New York, who would see it before the Statue of Liberty became visible. In 1915 the Sea Beach Line was upgraded to a subway line. This was followed by upgrades to the other former excursion roads, and the opening of the New West End Terminal in 1919, thus ushering in Coney Island's busiest era. Nathan's Famous original hot dog stand opened on Coney Island in 1916 and quickly became a landmark. An annual Nathan's Hot Dog Eating Contest has been held there annually on July 4 since its opening, but has only attracted broad attention and television coverage since the late 1990s. After World War II, the appeal of Coney Island started to lessen for several reasons. Air conditioning in movie theaters and subsequently in homes, provided a cool escape in summer without going to the beach. The advent of automobiles provided relatively easy access to the less crowded and more appealing Long Island state parks, especially Jones Beach State Park. Luna Park closed in 1946, after a series of fires. There was an increase in prostitution in the area, and the New York street gang problems of the 1950s also spilled over into Coney Island. The presence of threatening youths did not impact the beach-goers, but it discouraged visitors to the rides and concessions, which were staples of the Coney Island economy. The local economy was dealt a further severe blow by the 1964 closing of Steeplechase Park, the last of the major amusement parks...
Просмотров: 9032 Jeff Quitney
Pressure Cookers: "Food For Thought" ~ 1949 Pressure Cooking Institute; Spring Byington
 
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Kitchen, Dining, Appliances... playlist: https://www.youtube.com/playlist?list=PLDF09C81F8B179D80 more at http://quickfound.net "Entertaining and instructive demonstration of pressure cooking by Spring Byington." Produced by Dudley Pictures Corporation. Public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Pressure_cooking Pressure cooking is the process of cooking food, using water or other cooking liquid, in a sealed vessel, known as a pressure cooker. As pressure cooking cooks food faster than conventional cooking methods, it saves energy. Pressure is created by boiling a liquid, such as water or broth, inside the closed pressure cooker. The trapped steam increases the internal pressure and allows the temperature to rise. After use, the pressure is slowly released so that the vessel can be safely opened. Pressure cooking can be used for quick simulation of the effects of long braising. Almost any food which can be cooked in steam or water-based liquids can be cooked in a pressure cooker... History In 1679, the French physicist Denis Papin, better known for his studies on steam, invented the steam digester in an attempt to reduce the cooking time of food. His airtight cooker used steam pressure to raise the water's boiling point, thus cooking food much more quickly. In 1681, Papin presented his invention to the Royal Society of London, but the Society's members treated his invention as a scientific study. They granted him permission to become a member of the Society afterwards. In 1864, Georg Gutbrod of Stuttgart began manufacturing pressure cookers made of tinned cast iron. In 1918, Spain granted a patent for the pressure cooker to Jose Alix Martínez from Zaragoza. Martínez named it the olla exprés, literally "express cooking pot", under patent number 71143 in the Boletín Oficial de la Propiedad Industrial. In 1924, the first pressure cooking pot recipe book was published, written by José Alix and titled "360 fórmulas de cocina Para guisar con la 'olla expres'", or 360 recipes for cooking with a pressure cooker. In 1938, Alfred Vischer presented his invention, the Flex-Seal Speed Cooker, in New York City. Vischer's pressure cooker was the first one designed for home use, and its success led to competition among American and European manufacturers.[3] At the 1939 New York World's Fair, National Presto Industries, which was then known as the "National Pressure Cooker Company", introduced its own pressure cooker. Variants An autoclave is a type of pressure cooker used by laboratories and hospitals to sterilize equipment. In the food industry, pressure cookers are often referred to as retorts or canning retorts. Large pressure cookers are often called pressure canners in the United States, because of their capacity to hold jars used in canning. Pressure canners are specifically designed for home canning, whereas ordinary pressure cookers are not recommended for canning due to the risk of botulism poisoning, because pressure canners hold heat and pressure for much longer than ordinary pressure cookers; these factors are a critical part of the total processing time required to destroy harmful microbes. Pressure fryers are used for deep fat frying under pressure, because ordinary pressure cookers are not suitable for pressure frying... Pressure cookers are typically made of aluminum (aluminium) or stainless steel. Aluminum pressure cookers may be stamped, polished, or anodized, but all are unsuitable for the dishwasher. They are cheaper, but the aluminum is reactive to acidic foods, whose flavors are changed in the reactions, and less durable than stainless steel pressure cookers. Higher-quality stainless steel pressure cookers are made with heavy, three-layer, or copper-clad bottoms (heat spreader) for uniform heating because stainless steel has lower thermal conductivity.
Просмотров: 110151 Jeff Quitney
Orion Spacecraft Heat Shield 2014 NASA; Engineer Molly White
 
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more at http://scitech.quickfound.net/astro/orion_cev_news_and_links.html Orion spacecraft heat shield engineer Molly White explains the basics on the Orion thermal protection system. Includes animated and time lapse footage. Public domain film from NASA. http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Orion_(spacecraft) The Orion Multi-Purpose Crew Vehicle (Orion MPCV) is a spacecraft intended to carry a crew of up to four astronauts to destinations at or beyond low Earth orbit (LEO). Currently under development by NASA for launch on the Space Launch System, Orion is intended to facilitate human exploration of asteroids and of Mars, as well as to provide a means of delivering or retrieving crew or supplies from the ISS if needed. The MPCV was announced by NASA on May 24, 2011. Its design is based on the Orion Crew Exploration Vehicle from the cancelled Constellation program. It has two main modules. The Orion command module is being built by Lockheed Martin at the Michoud Assembly Facility in New Orleans. The Orion Service Module, provided by the European Space Agency, is being built by Airbus Defence and Space. The MPCV's first test flight (uncrewed), known as Exploration Flight Test 1 (EFT-1), was launched atop a Delta IV Heavy rocket on December 5, 2014 on a flight lasting 4 hours and 24 minutes, landing at its target in the Pacific Ocean at 10:29 Central (delayed from the previous day due to technical and weather problems). The first mission to carry astronauts is not expected to take place until 2021 at the earliest... The Orion crew module (CM) is the reusable transportation capsule that provides a habitat for the crew, provides storage for consumables and research instruments, and serves as the docking port for crew transfers. The crew module is the only part of the MPCV that returns to Earth after each mission and is a 57.5° frustum shape, similar to that of the Apollo command module. As projected, the CM will be 5.02 meters (16 ft 6 in) in diameter and 3.3 meters (10 ft 10 in) in length, with a mass of about 8.5 metric tons (19,000 lb). It was manufactured by the Lockheed Martin Corporation. It will have more than 50% more volume than the Apollo capsule, which had an interior volume of 5.9 m3 (210 cu ft), and will carry four to six astronauts.[38] After extensive study, NASA has selected the Avcoat ablator system for the Orion crew module. Avcoat, which is composed of silica fibers with a resin in a honeycomb made of fiberglass and phenolic resin, was previously used on the Apollo missions and on select areas of the space shuttle for early flights. Orion's CM will use advanced technologies, including: - "Glass cockpit" digital control systems derived from those of the Boeing 787 Dreamliner. - An "autodock" feature, like those of Russian Progress spacecraft and the European Automated Transfer Vehicle, with provision for the flight crew to take over in an emergency. Previous American spacecraft (Gemini, Apollo, and Space Shuttle) have all required manual piloting for docking. - Improved waste-management facilities... - A nitrogen/oxygen (N2/O2) mixed atmosphere at either sea level (101.3 kPa or 14.69 psi) or slightly reduced (55.2 to 70.3 kPa or 8.01 to 10.20 psi) pressure. - Much more advanced computers than on previous crew vehicles. The CM will be constructed of the aluminium-lithium alloy used on the shuttle's external tank, and on the Delta IV and Atlas V rockets. The CM itself will be covered in the same Nomex felt-like thermal protection blankets used on parts on the shuttle not subject to critical heating, such as the payload bay doors. The reusable recovery parachutes will be based on the parachutes used on both the Apollo spacecraft and the Space Shuttle Solid Rocket Boosters, and will also use the same Nomex cloth for construction. Water landings will be the exclusive means of recovery for the Orion CM. To allow Orion to mate with other vehicles it will be equipped with the NASA Docking System... The spacecraft will employ a Launch Escape System (LES) like that used in Mercury and Apollo, along with an Apollo-derived "Boost Protective Cover" (made of fiberglass), to protect the Orion CM from aerodynamic and impact stresses during the first 2 1⁄2 minutes of ascent. Its designers claim that the MPCV is designed to be 10 times safer during ascent and reentry than the Space Shuttle. The CM is designed to be refurbished and reused. In addition, all of the Orion's component parts have been designed to be as generic as possible, so that between the craft's first test flight in 2014 and its projected Mars voyage in the 2030s, the spacecraft can be upgraded as new technologies become available...
Просмотров: 4709 Jeff Quitney
B-24 Liberator: "Ditching of a B-24 Airplane into the James River" 1944 NACA Langley Research Center
 
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more at http://scitech.quickfound.net/ "Experimental ditching test conducted by NASA Langley Researcher. The B-24 was ditched into the James River on September 20, 1944. A pilot flew the plane into the water and the B-24 definitely experienced damage." Silent. Public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. also see: B-24 Bomber Crash Landings: "24s Get Back" https://www.youtube.com/watch?v=Hv6D8_p7ozw Reupload of a previously uploaded film with improved video. http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Consolidated_B-24_Liberator The Consolidated B-24 Liberator was an American heavy bomber, designed by Consolidated Aircraft of San Diego, California. It was known within the company as the Model 32, and a small number of early models were sold under the name LB-30, for Land Bomber. The B-24 was used in World War II by several Allied air forces and navies, and by every branch of the American armed forces during the war, attaining a distinguished war record with its operations in the Western European, Pacific, Mediterranean, and China-Burma-India Theaters. Often compared with the better-known Boeing B-17 Flying Fortress, the B-24 was a more modern design with a higher top speed, greater range, and a heavier bomb load; however, it was also more difficult to fly, with heavy control forces and poor formation-flying characteristics. Popular opinion among aircrews and general staffs tended to favor the B-17's rugged qualities above all other considerations in the European Theater. The placement of the B-24's fuel tanks throughout the upper fuselage and its lightweight construction, designed to increase range and optimize assembly line production, made the aircraft vulnerable to battle damage.[4] The B-24 was notorious among American aircrews for its tendency to catch fire. Moreover, its high fuselage-mounted "Davis wing" also meant it was dangerous to ditch or belly land, since the fuselage tended to break apart. Nevertheless, the B-24 provided excellent service in a variety of roles thanks to its large payload and long range, and was the only bomber to operationally deploy the United States' first forerunner to precision-guided munitions during the war, the 1,000 lb. Azon guided bomb. The B-24's most infamous mission was the low-level strike against the Ploiești oil fields, in Romania on 1 August 1943, which turned into a disaster because the enemy was underestimated, fully alerted and attackers disorganized. The B-24 ended World War II as the most produced heavy bomber in history. At over 18,400 units, half by Ford Motor Company, it still holds the distinction as the most-produced American military aircraft... Development The Liberator originated from a United States Army Air Corps (USAAC) request in 1938 for Consolidated to produce the B-17 under license... Consolidated decided instead to submit a more modern design of its own. Specifications The new Model 32 combined the Davis wing, a high efficiency airfoil design created by unorthodox means by a lone inventor named David Davis,[8] the twin tail design from the Consolidated Model 31 flying boat, and mated both together on a new fuselage. This new fuselage was intentionally designed around the twin bomb bays, each one being the same size and capacity of the B-17... The program was run under the umbrella group running "Project A", an Air Corps requirement for an intercontinental bomber that had been conceived in the mid-1930s. Although the B-24 did not meet Project A goals, it was a step in that direction. Project A led to the development of the Boeing B-29 and Consolidated's own B-32 and B-36. Contract The contract for a prototype was awarded in March 1939... Compared to the B-17, the proposed Model 32 had a shorter fuselage and 25% less wing area, but had a 6 ft (1.8 m) greater wingspan and a substantially larger carrying capacity, as well as a distinctive twin tail. Whereas the B-17 used 9-cylinder Wright R-1820 Cyclone engines, the Consolidated design used twin-row, 14-cylinder Pratt & Whitney R-1830 "Twin Wasp" radials of 1,000 hp (746 kW)... Design The B-24's spacious, slab-sided fuselage (which earned the aircraft the nickname "Flying Boxcar") was built around a central bomb bay that could accommodate up to 8,000 lb (3,629 kg) of ordnance in each of its forward and aft compartments. The equal-capacity forward and aft bomb bay compartments were further split longitudinally with a centerline ventral catwalk just nine inches (23 cm) wide, which also functioned as the fuselage's structural keel beam...The B-24 was sometimes disparaged as "The Flying Coffin" because the only entry and exit from the bomber was in the rear...
Просмотров: 30647 Jeff Quitney
Industrial Design: "American Look" 1958 General Motors Populuxe Classic Film
 
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more at http://shops.quickfound.net/ "The definitive Populuxe film on 1950s automotive, industrial, interior and architectural design." see also: American Thrift 1962 Chevrolet https://www.youtube.com/watch?v=suuXxJIyk6I Public domain film from the Library of Congress Prelinger Archive, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and equalization. http://en.wikipedia.org/wiki/Industrial_design Industrial design is the use of a combination of applied art and applied science to improve the aesthetics, ergonomics, and usability of a product, but it may also be used to improve the product's marketability and production. The role of an industrial designer is to create and execute design solutions for problems of form, usability, physical ergonomics, marketing, brand development, and sales. The first use of the term "industrial design" is often attributed to the designer Joseph Claude Sinel in 1919 (although he himself denied this in interviews), but the discipline predates 1919 by at least a decade. Its origins lie in the industrialization of consumer products. For instance the Deutscher Werkbund, founded in 1907 and a precursor to the Bauhaus, was a state-sponsored effort to integrate traditional crafts and industrial mass-production techniques, to put Germany on a competitive footing with England and the United States... Notable industrial designers A number of industrial designers have made such a significant impact on culture and daily life that they have attained a level of notability beyond that of an average designer. Alvar Aalto, renowned as an architect, also designed a significant number of household items, such as chairs, stools, lamps, a tea-cart, and vases. Raymond Loewy was a prolific American designer who is responsible for the Royal Dutch Shell corporate logo, the original BP logo (in use until 2000), the PRR S1 steam locomotive, the Studebaker Starlight (including the later iconic bulletnose), as well as Schick electric razors, Electrolux refrigerators, short-wave radios, Le Creuset French ovens, and a complete line of modern furniture, among many other items. Richard A. Teague, who spent most of his career with the American Motor Company, originated the concept of using interchangeable body panels so as to create a wide array of different vehicles using the same stampings. He was responsible for such unique automotive designs as the Pacer, Gremlin, Matador coupe, Jeep Cherokee, and the complete interior of the Eagle Premier. Viktor Schreckengost designed bicycles manufactured by Murray bicycles for Murray and Sears, Roebuck and Company. With engineer Ray Spiller, he designed the first truck with a cab-over-engine configuration, a design in use to this day. Schreckengost also founded The Cleveland Institute of Art's school of industrial design. Charles and Ray Eames were most famous for their unique furniture design, such as the Eames Lounge Chair Wood and Eames Lounge Chair. Another example is German industrial designer Dieter Rams, who is closely associated with the consumer products company Braun (where he worked until 1995) and the Functionalist school of industrial design. He is famous for his "ten principles to good design", in addition to designing many iconic products at Braun. More recently, Jonathan Ive, the Senior Vice President of Design at Apple Inc., is credited for designing products for the company, which has a strong philosophy in aesthetics. His designs include the iPod and iPhone... http://en.wikipedia.org/wiki/Googie_architecture Googie architecture is a form of modern architecture, a subdivision of futurist architecture influenced by car culture and the Space and Atomic Ages. Originating in Southern California during the late 1940s and continuing approximately into the mid-1960s, Googie-themed architecture was popular among motels, coffee houses and gas stations. The school later became widely known as part of the Mid-Century modern style, elements of which represent the populuxe aesthetic, as in Eero Saarinen's TWA Flight Center. The term "Googie" comes from a now defunct coffee shop and cafe built in West Hollywood. Features of Googie include upswept roofs, curvaceous, geometric shapes, and bold use of glass, steel and neon. Googie was also characterized by Space Age designs depicting motion, such as boomerangs, flying saucers, atoms and parabolas, and free-form designs such as "soft" parallelograms and an artist's palette motif. These stylistic conventions represented American society's fascination with Space Age themes and marketing emphasis on futuristic designs. As with the Art Deco style of the 1930s, Googie became less valued as time passed, and many buildings built with this style have been destroyed...
Просмотров: 50343 Jeff Quitney
Airplane Propellers: Principles and Types 1941 US Army Air Corps Pilot Training Film
 
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Pilot Training Film playlist: https://www.youtube.com/playlist?list=PLCA6387BA013F9A4D USAF Training Film playlist: https://www.youtube.com/playlist?list=PL8F26D920AA815835 more at http://scitech.quickfound.net/aviation_news_and_search.html "Until the days of supersonic speed and jet propulsion of rocket ships, the propeller is a relatively efficient method of moving our airplanes through the air up to speeds of 5 to 6 hundred miles per hour. In general, the size of a propeller is dependent upon the power of the engine..." US Army Air Corps Pilot Training Film TF1-246 Originally a public domain film from the US Army Air Corps, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). https://en.wikipedia.org/wiki/Propeller_(aeronautics) Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ An aircraft propeller, or airscrew, converts rotary motion from an engine or other mechanical power source, to provide propulsive force. It comprises a rotating power-driven hub, to which are attached several radial airfoil-section blades such that the whole assembly rotates about a longitudinal axis. The blade pitch may be fixed, manually variable to a few set positions, or of the automatically-variable "constant-speed" type. The propeller attaches to the power source's driveshaft either directly or, especially on larger designs, through reduction gearing. Most early aircraft propellers were carved by hand from solid or laminated wood, while metal construction later became popular. More recently, composite materials are becoming increasingly used. Propellers are only suitable for use at subsonic airspeeds up to around 480 mph (770 km/h), as above this speed the blade tip speed begins to go supersonic, with the consequent shockwaves causing high drag and other mechanical difficulties... The earliest references for vertical flight came from China. Since around 400 BC, Chinese children have played with bamboo flying toys. This bamboo-copter is spun by rolling a stick attached to a rotor between ones hands. The spinning creates lift, and the toy flies when released. The 4th-century AD Daoist book Baopuzi by Ge Hong (抱朴子 "Master who Embraces Simplicity") reportedly describes some of the ideas inherent to rotary wing aircraft. Designs similar to the Chinese helicopter toy appeared in Renaissance paintings and other works... Theory and design of aircraft propellers A well-designed propeller typically has an efficiency of around 80% when operating in the best regime. The efficiency of the propeller is influenced by the angle of attack (α). This is defined as α = Φ - θ, where θ is the helix angle (the angle between the resultant relative velocity and the blade rotation direction) and Φ is the blade pitch angle. Very small pitch and helix angles give a good performance against resistance but provide little thrust, while larger angles have the opposite effect. The best helix angle is when the blade is acting as a wing producing much more lift than drag. Angle of attack is similar to advance ratio, for propellers...
Просмотров: 25232 Jeff Quitney
How to Succeed with Brunettes 1967 US Navy Training Film
 
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more at http://dating.quickfound.net/ Demonstrates proper dating etiquette for US Navy officers, at first by showing what NOT to do. US Navy Training Film MN-10283C NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=rAuwpUfObcI Public domain film from the US National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ http://en.wikipedia.org/wiki/Dating Dating as an institution is a relatively recent phenomenon which has mainly emerged in the last few centuries. From the standpoint of anthropology and sociology, dating is linked with other institutions such as marriage and the family which have also been changing rapidly and which have been subject to many forces, including advances in technology and medicine. As humans have evolved from the hunter-gatherers into civilized societies and more recently into modern societies, there have been substantial changes in the relationship between men and women, with perhaps the only biological constant being that both adult women and men must have sexual intercourse for human procreation to happen... Generally, during much of recorded history of humans in civilization, and into the Middle Ages in Europe, weddings were seen as business arrangements between families, while romance was something that happened outside of marriage discreetly, such as covert meetings... A few centuries ago, dating was sometimes described as a "courtship ritual where young women entertained gentleman callers, usually in the home, under the watchful eye of a chaperone,"[8] but increasingly, in many Western countries, it became a self-initiated activity with two young people going out as a couple in public together... In the twentieth century, dating was sometimes seen as a precursor to marriage but it could also be considered as an end-in-itself, that is, an informal social activity akin to friendship. It generally happened in that portion of a person's life before the age of marriage..
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Supermarket Checkers: "The Front Line" 1965 Reader's Digest; Grocery Store Cashier Training
 
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Food & Beverage playlist: https://www.youtube.com/playlist?list=PL12ED9F0F94A97DA0 more at http://food.quickfound.net "How to be an effective supermarket checker." Features former "International Checker of the Year" champions. Presented by Reader's Digest in cooperation with Super Market Institute. Public domain film from the Library of Congress Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). http://creativecommons.org/licenses/by-sa/3.0/ https://en.wikipedia.org/wiki/Supermarket A supermarket, a large form of the traditional grocery store, is a self-service shop offering a wide variety of food and household products, organized into aisles. It is larger and has a wider selection than a traditional grocery store, but is smaller and more limited in the range of merchandise than a hypermarket or big-box market. The supermarket typically comprises meat, fresh produce, dairy, and baked goods aisles, along with shelf space reserved for canned and packaged goods as well as for various non-food items such as kitchenware, household cleaners, pharmacy products and pet supplies... In the early days of retailing, all products generally were fetched by an assistant from shelves behind the merchant's counter while customers waited in front of the counter and indicated the items they wanted. Also, most foods and merchandise did not come in individually wrapped consumer-sized packages, so an assistant had to measure out and wrap the precise amount desired by the consumer. This also offered opportunities for social interaction: many regarded this style of shopping as "a social occasion" and would often "pause for conversations with the staff or other customers." These practices were by nature very labor-intensive and therefore also quite expensive. The shopping process was slow, as the number of customers who could be attended to at one time was limited by the number of staff employed in the store. Shopping for groceries also often involved trips to multiple specialty shops, such as a greengrocer, butcher, bakery, fishmonger and dry goods store, in addition to a general store, while milk was delivered by a milkman. The concept of an inexpensive food market relying on large economies of scale was developed by Vincent Astor. He founded the Astor Market in 1915, investing $750,000 ($18 million in 2015 currency) of his fortune into a 165' by 125' corner of 95th and Broadway, Manhattan, creating, in effect, an open air mini-mall that sold meat, fruit, produce and flowers. The expectation was that customers would come from great distances ("miles around"), but in the end even attracting people from ten blocks away was difficult, and the market folded in 1917. The concept of a self-service grocery store was developed by entrepreneur Clarence Saunders and his Piggly Wiggly stores. His first store opened in 1916. Saunders was awarded a number of patents for the ideas he incorporated into his stores. The stores were a financial success and Saunders began to offer franchises. The Great Atlantic & Pacific Tea Company, which was established in 1859, was another successful early grocery store chain in Canada and the United States, and became common in North American cities in the 1920s. The general trend in since then has been to stock shelves at night so that customers, the following day, can obtain their own goods and bring them to the front of the store to pay for them. Although there is a higher risk of shoplifting, the costs of appropriate security measures ideally will be outweighed by reduced labor costs. Early self-service grocery stores did not sell fresh meats or produce. Combination stores that sold perishable items were developed in the 1920s. Historically, there was debate about the origin of the supermarket, with King Kullen and Ralphs of California having strong claims... It has been determined that the first true supermarket in the United States was opened by a former Kroger employee, Michael J. Cullen, on 4 August 1930, inside a 6,000-square-foot (560 m2) former garage in Jamaica, Queens in New York City. The store, King Kullen, operated under the slogan "Pile it high. Sell it low." At the time of Cullen's death in 1936, there were seventeen King Kullen stores in operation. Although Saunders had brought the world self-service, uniform stores and nationwide marketing, Cullen built on this idea by adding separate food departments, selling large volumes of food at discount prices and adding a parking lot...
Просмотров: 65335 Jeff Quitney
Auto Repair: Starter Motors "Principles of the Starting Motor" 1956 US Army Auto Mechanics
 
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NEW VERSION with improved video & sound: https://www.youtube.com/watch?v=esVXvjTvuQo More at http://auto-parts.quickfound.net/ "ELECTRICAL AND MAGNETIC PRINCIPLES INVOLVED IN THE OPERATION OF THE STARTING MOTOR - HOW ELECTRICAL ENERGY IS CONVERTED TO MECHANICAL ENERGY." Public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied. The soundtrack was also processed with volume normalization, clipping reduction, and equalization. Split with MKVmerge GUI (part of MKVToolNix), the same software can recombine the downloaded parts (in mp4 format): http://www.bunkus.org/videotools/mkvtoolnix/doc/mkvmerge-gui.html US Army training film TF9-2331 see also: power steering: http://www.youtube.com/watch?v=AlpvyWAA8a0 drum brakes: http://www.youtube.com/watch?v=n20sTZggvYc planetary gears: http://www.youtube.com/watch?v=p8fAHTeDGiQ http://en.wikipedia.org/wiki/Starter_motor ...The modern starter motor is either a permanent-magnet or a series-parallel wound direct current electric motor with a starter solenoid (similar to a relay) mounted on it. When current from the starting battery is applied to the solenoid, usually through a key-operated switch, the solenoid engages a lever that pushes out the drive pinion on the starter driveshaft and meshes the pinion with the starter ring gear on the flywheel of the engine. The solenoid also closes high-current contacts for the starter motor, which begins to turn. Once the engine starts, the key-operated switch is opened, a spring in the solenoid assembly pulls the pinion gear away from the ring gear, and the starter motor stops. The starter's pinion is clutched to its driveshaft through an overrunning sprag clutch which permits the pinion to transmit drive in only one direction. In this manner, drive is transmitted through the pinion to the flywheel ring gear, but if the pinion remains engaged (as for example because the operator fails to release the key as soon as the engine starts, or if there is a short and the solenoid remains engaged), the pinion will spin independently of its driveshaft. This prevents the engine driving the starter, for such backdrive would cause the starter to spin so fast as to fly apart. However, this sprag clutch arrangement would preclude the use of the starter as a generator if employed in hybrid scheme mentioned above, unless modifications were made. Also, a standard starter motor is only designed for intermittent use which would preclude its use as a generator; the electrical components are designed only to operate for typically under 30 seconds before overheating (by too-slow dissipation of heat from ohmic losses), to save weight and cost. This is the same reason why most automobile owner's manuals instruct the operator to pause for at least ten seconds after each ten or fifteen seconds of cranking the engine, when trying to start an engine that does not start immediately. This overrunning-clutch pinion arrangement was phased into use beginning in the early 1960s; before that time, a Bendix drive was used... An intermediate development between the Bendix drive developed in the 1930s and the overrunning-clutch designs introduced in the 1960s was the Bendix Folo-Thru drive... Chrysler Corporation contributed materially to the modern development of the starter motor. In 1962, Chrysler introduced a starter incorporating a geartrain between the motor and the driveshaft. Rolls Royce had introduced a conceptually similar starter in 1946, but Chrysler's was the first volume-production unit. The motor shaft has integrally cut gear teeth forming a pinion which meshes with a larger adjacent driven gear to provide a gear reduction ratio of 3.75:1. This permits the use of a higher-speed, lower-current, lighter and more compact motor assembly while increasing cranking torque. Variants of this starter design were used on most rear- and four-wheel-drive vehicles produced by Chrysler Corporation from 1962 through 1987. It makes a unique, distinct sound when cranking the engine, which led to it being nicknamed the "Highland Park Hummingbird"—a reference to Chrysler's headquarters in Highland Park, Michigan. The Chrysler gear-reduction starter formed the conceptual basis for the gear-reduction starters that now predominate in vehicles on the road. Many Japanese automakers phased in gear reduction starters in the 1970s and 1980s. Light aircraft engines also made extensive use of this kind of starter, because its light weight offered an advantage. Those starters not employing offset geartrains like the Chrysler unit generally employ planetary epicyclic geartrains instead. Direct-drive starters are almost entirely obsolete owing to their larger size, heavier weight and higher current requirements.
Просмотров: 79747 Jeff Quitney