12 résultats pour "engineer"
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Leonardo da Vinci
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INTRODUCTION
Leonardo da Vinci
Leonardo da Vinci was known not only as a masterful painter but as an architect, sculptor, engineer, and scientist.
and conservation program made use of the latest technology to reverse some of the damage. Although much of the original surface is gone, the majesty of thecomposition and the penetrating characterization of the figures give a fleeting vision of its vanished splendor. The Virgin of the RocksThe Virgin of the Rocks by Leonardo da Vinci was actually painted twice. The first version, done in 1485, wascommissioned to be an altarpiece but was evidently rejected. That painting now hangs in the Louvre,...
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Industrial Revolution
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INTRODUCTION
Industrial Revolution, widespread replacement of manual labor by machines that began in Britain in the 18th century and is still continuing in some parts of the world.
The most important advance in iron production occurred in 1784 when Englishman Henry Cort invented new techniques for rolling raw iron, a finishing process thatshapes iron into the desired size and form. These advances in metalworking were an important part of industrialization. They enabled iron, which was relativelyinexpensive and abundant, to be used in many new ways, such as building heavy machinery. Iron was well suited for heavy machinery because of its strength anddurability. Because of t...
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Industrial Revolution .
The most important advance in iron production occurred in 1784 when Englishman Henry Cort invented new techniques for rolling raw iron, a finishing process thatshapes iron into the desired size and form. These advances in metalworking were an important part of industrialization. They enabled iron, which was relativelyinexpensive and abundant, to be used in many new ways, such as building heavy machinery. Iron was well suited for heavy machinery because of its strength anddurability. Because of t...
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Helicopter.
naturally flaps down so as to increase lift. Flapping allows the differences in lift caused by uneven rotor tip speed to cancel out, producing a stable ride. Many helicoptersuse mechanical hinges with lubricated bearings, but some use flexible straps made of a composite material in order to reduce the required maintenance. Helicopters require different amounts of lift and thrust at different times during flight, because the aerodynamic forces acting on them change during hovering andacceleration...
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Manhattan Project - U.
other possible uses of nuclear energy, such as using uranium to operate large power plants or, perhaps, as power sources for ships or submarines. Then Nazi Germanyinvaded Poland on September 1, 1939, and Europe plunged into war. The scientists realized that any plans to build large-scale nuclear power plants would have to waituntil the war was over. Two weeks after the invasion of Poland, Hitler made a radio speech in which he threatened Britain with “a weapon against which there is no defense.”...
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Turbine.
steam turbine has supplanted the reciprocating engine as a prime mover in large electricity-generating plants and is also used as a means of jet propulsion. Steam turbines are used in the generation of nuclear power and in nuclear ship propulsion. They operate with fuel-fired boilers for power generation. In cogenerationapplications requiring both process heat (heat used in an industrial process) and electricity, steam is raised at high pressure in the boiler and extracted from the turbineat the...
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Panama Canal - Geography.
The size of ships using the Panama Canal has steadily increased. About 27 percent of the vessels that use the canal are built to the maximum dimensions that can passthrough it (a category called “Panamax”). This has prompted further widening of Gaillard Cut, so that the larger Panamax vessels may transit safely. However, some ofthe world’s commercial and military ships are too large for the canal. Since the 1940s, new U.S. battleships and aircraft carriers have been built exceeding the canal’sdi...
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Please forward us your résumé, including previous research experience, graduate and postgraduate transcripts, and two
letters of recommendation.
could check iton this, too." Itold himIcould setupane-mail account forhim ifhe wanted. Hesaid, "Yeah?" Itook his device, whichIwasn't familiar with,butfigured outpretty quickly, andseteverything up.Isaid, "What doyou want fora user name?" Isuggested "Allen,"or"AllenBlack," oranickname. "Or'Engineer.' Thatcould becool." Heput hisfinger on his mustache andthought aboutit.Iasked ifhe had anykids. Hesaid, "Ason. Soon he'sgoing tobe taller thanme.Taller and smarter. He'llbeagreat doctor. Abrain surge...
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Latin American Architecture
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INTRODUCTION
Oldest Cathedral in the Western Hemisphere
The oldest cathedral in the Western hemisphere is the Cathedral of Santa Maria la Menor, constructed between 1512 and
1541 in Santo Domingo, now the capitol of the Dominican Republic.
Colonial FortressThe imposing fortress of San Felipe de Barajas, in the foreground, was built in the mid-17th century to defend the colonialport settlement of Cartagena. Modern day Cartagena, Colombia, can be seen in the background.Dave G. Houser/Post-Houserstock/Corbis The use of architecture and urban planning as tools of European conquest is a recurrent theme in Latin American history. King Philip II of Spain ordered town plannersto use a grid or checkerboard plan for the layout of new towns...
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Internal-Combustion Engine.
any Otto-cycle engine and in actual engines today is slightly more than 40 percent. Diesels are, in general, slow-speed engines with crankshaft speeds of 100 to 750revolutions per minute (rpm) as compared to 2500 to 5000 rpm for typical Otto-cycle engines. Some types of diesel, however, have speeds up to 2000 rpm. Becausediesels use compression ratios of 14 or more to 1, they are generally more heavily built than Otto-cycle engines, but this disadvantage is counterbalanced by theirgreater effici...
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Army.
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INTRODUCTION
Army, military land forces of a nation, assembled, drilled, disciplined,
disappearance for several centuries of large standing armies in Europe. A Middle Ages Feudalism was based on a concept of local defense, each baron or landowner governing land that had been given him by the king, and each lord having his ownpersonal protective forces recruited from among men who worked for him. In return, each lord and his men were pledged to annual service to the monarch and couldbe called on in special instances, as in the defense of Christendom during the Crusades. National...
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Technology.
loose soil in this region, known as the Fertile Crescent, was easily scratched for planting, and an abundance of trees was available for firewood. By 5000 BC, farming communities were established in areas known today as Syria, Turkey, Lebanon, Israel, Jordan, Greece, and the islands of Crete and Cyprus. Agricultural societies in these places constructed stone buildings, used the sickle to harvest grain, developed a primitive plowstick, and advanced their skills inmetalworking. Trade in flint al...