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Vannevar Bush ( ; March 11, 1890 – June 28, 1974) was an American engineer, inventor and science administrator, who during World War II headed the U.S. Office of Scientific Research and Development (OSRD), through which almost all wartime military R&D was carried out, including initiation and early administration of the Manhattan Project. He is also known in engineering for his work on analog computers, for founding Raytheon, and for the memex, a hypothetical adjustable microfilm viewer with a structure analogous to that of hypertext. In 1945, Bush published the essay "As We May Think" in which he predicted that "wholly new forms of encyclopedias will appear, ready made with a mesh of associative trails running through them, ready to be dropped into the memex and there amplified".〔 The memex influenced generations of computer scientists, who drew inspiration from its vision of the future. For his master's thesis, Bush invented and patented a "profile tracer", a mapping device for assisting surveyors. It was the first of a string of inventions. He joined the Department of Electrical Engineering at Massachusetts Institute of Technology (MIT) in 1919, and founded the company now known as Raytheon in 1922. Starting in 1927, Bush constructed a differential analyzer, an analog computer with some digital components that could solve differential equations with as many as 18 independent variables. An offshoot of the work at MIT by Bush and others was the beginning of digital circuit design theory. Bush became vice president of MIT and dean of the MIT School of Engineering in 1932, and president of the Carnegie Institution of Washington in 1938. Bush was appointed to the National Advisory Committee for Aeronautics (NACA) in 1938, and soon became its chairman. As chairman of the National Defense Research Committee (NDRC), and later director of OSRD, Bush coordinated the activities of some six thousand leading American scientists in the application of science to warfare. Bush was a well-known policymaker and public intellectual during World War II, when he was in effect the first presidential science advisor. As head of NDRC and OSRD, he initiated the Manhattan Project, and ensured that it received top priority from the highest levels of government. In ''Science, The Endless Frontier'', his 1945 report to the President of the United States, Bush called for an expansion of government support for science, and he pressed for the creation of the National Science Foundation. == Early life and work == Vannevar Bush was born in Everett, Massachusetts, on March 11, 1890, the third child and only son of Perry Bush, the local Universalist pastor, and his wife Emma Linwood née Paine. He had two older sisters, Edith and Reba. He was named after John Vannevar, an old friend of the family who had attended Tufts College with Perry. The family moved to Chelsea, Massachusetts, in 1892, and Bush graduated from Chelsea High School in 1909. He then attended Tufts College, like his father before him. A popular student, he was vice president of his sophomore class, and president of his junior class. During his senior year, he managed the football team. He became a member of the Alpha Tau Omega fraternity, and dated Phoebe Clara Davis, who also came from Chelsea. Tufts allowed students to gain a master's degree in four years simultaneously with a bachelor's degree, so for his master's thesis, Bush invented and patented a "profile tracer". This was a device for assisting surveyors that looked like a lawn mower. It had two bicycle wheels, and a pen that plotted the terrain over which it traveled. It was the first of a string of inventions.〔(【引用サイトリンク】title=Vannevar Bush's Profile Tracer )〕 On graduation in 1913 he received both bachelor of science and master of science degrees. After graduation, Bush worked at General Electric (GE) in Schenectady, New York, for $14 a week. As a "test man", his job was to assess equipment to ensure that it was safe. He transferred to GE's plant in Pittsfield, Massachusetts, to work on high voltage transformers, but after a fire broke out at the plant, Bush and the other test men were suspended. He returned to Tufts in October 1914 to teach mathematics, and spent the 1915 summer break working at the Brooklyn Navy Yard as an electrical inspector. He was awarded a $1,500 scholarship to study at Clark University as a doctoral student of Arthur Gordon Webster, but Webster wanted Bush to study acoustics. Bush preferred to quit rather than study a subject that did not interest him, and he subsequently enrolled in the Massachusetts Institute of Technology (MIT) electrical engineering program. Spurred by the need for enough financial security to marry, he submitted his thesis, entitled ''Oscillating-Current Circuits: An Extension of the Theory of Generalized Angular Velocities, with Applications to the Coupled Circuit and the Artificial Transmission Line'', in April 1916. His adviser, Arthur Edwin Kennelly, tried to demand more work from him, but Bush refused, and Kennelly was overruled by the department chairman; Bush received his doctorate in engineering jointly from MIT and Harvard University. He married Phoebe in August 1916. Their marriage produced two sons: Richard Davis Bush and John Hathaway Bush. Bush accepted a job with Tufts, where he became involved with the American Radio and Research Corporation (AMRAD), which began broadcasting music from the campus on March 8, 1916. The station owner, Harold Power, hired him to run the company's laboratory, at a salary greater than that which Bush drew from Tufts. In 1917, following the United States' entry into World War I, he went to work with the National Research Council. He attempted to develop a means of detecting submarines by measuring the disturbance in the Earth's magnetic field. His device worked as designed, but only from a wooden ship; attempts to get it to work on a metal ship such as a destroyer failed. Bush left Tufts in 1919, although he remained employed by AMRAD, and joined the Department of Electrical Engineering at MIT, where he worked under Dugald C. Jackson. In 1922, he collaborated with fellow MIT professor William H. Timbie on ''Principles of Electrical Engineering'', an introductory textbook. AMRAD's lucrative contracts from World War I had been cancelled, and Bush attempted to reverse the company's fortunes by developing a thermostatic switch invented by Al Spencer, an AMRAD technician, on his own time. AMRAD's management was not interested in the device, but had no objection to its sale. Bush found backing from Laurence K. Marshall and Richard S. Aldrich to create the Spencer Thermostat Company, which hired Bush as a consultant. The new company soon had revenues in excess of a million dollars. It merged with General Plate Company to form Metals & Controls Corporation in 1931, and with Texas Instruments in 1959. Texas Instruments sold it to Bain Capital in 2006, and it became a separate company again as Sensata Technologies in 2010.〔(【引用サイトリンク】url=http://investors.sensata.com/phoenix.zhtml?c=210277&p=irol-historycomp )〕 In 1924, Bush and Marshall teamed up with physicist Charles G. Smith, who had invented a device called the S-tube. This enabled radios, which had previously required two different types of batteries, to operate from mains power. Marshall raised $25,000 to set up the American Appliance Company on July 7, 1922, to market the invention, with Bush and Smith among its five directors. The venture made Bush wealthy, and the company, now known as Raytheon, ultimately became a large electronics company and defense contractor. Starting in 1927, Bush constructed a differential analyzer, an analog computer that could solve differential equations with as many as 18 independent variables. This invention arose from previous work performed by Herbert R. Stewart, one of Bush's masters students, who at Bush's suggestion created the integraph, a device for solving first-order differential equations, in 1925. Another student, Harold Hazen, proposed extending the device to handle second-order differential equations. Bush immediately realized the potential of such an invention, for these were much more difficult to solve, but also quite common in physics. Under Bush's supervision, Hazen was able to construct the differential analyzer, a table-like array of shafts and pens that mechanically simulated and plotted the desired equation. Unlike earlier designs that were purely mechanical, the differential analyzer had both electrical and mechanical components. Among the engineers who made use of the differential analyzer was General Electric's Edith Clarke, who used it to solve problems relating to electric power transmission. For developing the differential analyzer, Bush was awarded the Franklin Institute's Louis E. Levy Medal in 1928. An offshoot of the work at MIT was the beginning of digital circuit design theory by one of Bush's graduate students, Claude Shannon. Working on the analytical engine, Shannon described the application of Boolean algebra to electronic circuits in his landmark master's thesis, ''A Symbolic Analysis of Relay and Switching Circuits''. In 1935, Bush was approached by OP-20-G, which was searching for an electronic device to aid in codebreaking. Bush was paid a $10,000 fee to design the Rapid Analytical Machine (RAM). The project went over budget and was not delivered until 1938, when it was found to be unreliable in service. Nonetheless, it was an important step toward creating such a device. The reform of the administration of MIT began in 1930 with the appointment of Karl T. Compton as president. Bush and Compton soon clashed over the issue of limiting the amount of outside consultancy by professors, a battle Bush quickly lost, but the two men soon built a solid professional relationship. Compton appointed Bush to the newly created post of vice president in 1932. That year Bush also became the dean of the MIT School of Engineering. The two positions came with a salary of $12,000 plus $6,000 for expenses per annum. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Vannevar Bush」の詳細全文を読む スポンサード リンク
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