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Complex Number Calculator
George Robert Stibitz (April 30, 1904 – January 31, 1995) was a Bell Labs researcher internationally recognized as one of the fathers of the modern digital computer. He was known for his work in the 1930s and 1940s on the realization of Boolean logic digital circuits using electromechanical relays as the switching element. Stibitz was born in York, Pennsylvania. He received his bachelor's degree from Denison University in Granville, Ohio, his master's degree from Union College in 1927, and his Ph.D. in mathematical physics in 1930 from Cornell University. Computer In November 1937, George Stibitz, then working at Bell Labs (1930–1941), completed a relay-based adder he later dubbed the " Model K" (for "kitchen table", on which he had assembled it), which calculated using binary addition. Replicas of the "Model K" now reside in the Computer History Museum, the Smithsonian Institution, the William Howard Doane Library at Denison University and the American Computer Museum i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
York, Pennsylvania
York ( Pennsylvania Dutch: ''Yarrick''), known as the White Rose City (after the symbol of the House of York), is the county seat of York County, Pennsylvania, United States. It is located in the south-central region of the state. The population within York's city limits was 43,718 at the 2010 census, a 7.0% increase from the 2000 census count of 40,862. When combined with the adjacent boroughs of West York and North York and surrounding Spring Garden, West Manchester, and Springettsbury townships, the population of Greater York was 108,386. York is the 11th largest city in Pennsylvania. History 18th century York, also known as Yorktown in the mid 18th to early 19th centuries, was founded in 1741 by settlers from the Philadelphia region and named for the English city of the same name. By 1777, most of the area residents were of either German or Scots-Irish descent. York was incorporated as a borough on September 24, 1787, and as a city on January 11, 1887. York served ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Howard Doane
William Howard Doane (February 3, 1832 – December 24, 1915) was a manufacturer, inventor, hymn writer, choral director, church leader and philanthropist. He composed over 2,000 church hymns. More than seventy patents are credited to him for innovations in woodworking machinery. His philanthropy led to the renaming of the Granville Academy, as the Doane Academy, a boys' and girls' private preparatory school associated with Denison University in Granville, Ohio, where he was a major benefactor. Early life Doane was born in Preston, Connecticut on February 3, 1832. His parents were Joseph Howes Doane (1797-1854) and Frances Treat Doane (1799-1881). He was the fifth of eight children. His father was the head of Doane and Treat, cotton manufacturers. At a young age Doane showed impressive musical talent. By early adolescence he was playing the flute, violin and double bass fiddle. Doane attended the Woodstock Academy, a private secondary school affiliated with the Congregation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Electronics
Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. This is in contrast to analog electronics and analog signals. Digital electronic circuits are usually made from large assemblies of logic gates, often packaged in integrated circuits. Complex devices may have simple electronic representations of Boolean logic functions. History The binary number system was refined by Gottfried Wilhelm Leibniz (published in 1705) and he also established that by using the binary system, the principles of arithmetic and logic could be joined. Digital logic as we know it was the brain-child of George Boole in the mid 19th century. In an 1886 letter, Charles Sanders Peirce described how logical operations could be carried out by electrical switching circuits.Peirce, C. S., "Letter, Peirce to A. Marquand", dated 1886, '' Writings of Charles S. Peirce'', v. 5, 1993, pp. 541–3. GooglPreview See Burks, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of Scientific Research And Development
The Office of Scientific Research and Development (OSRD) was an agency of the United States federal government created to coordinate scientific research for military purposes during World War II. Arrangements were made for its creation during May 1941, and it was created formally by Executive Order 8807 on June 28, 1941. It superseded the work of the National Defense Research Committee (NDRC), was given almost unlimited access to funding and resources, and was directed by Vannevar Bush, who reported only to President Franklin Delano Roosevelt. The research was widely varied, and included projects devoted to new and more accurate bombs, reliable detonators, work on the proximity fuze, guided missiles, radar and early-warning systems, lighter and more accurate hand weapons, more effective medical treatments (including work to make penicillin at scale, which was necessary for its use as a drug), more versatile vehicles, and, the most secret of all, the S-1 Section, which later be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model V
The Model V was among the early electromechanical general purpose computers, designed by George Stibitz and built by Bell Telephone Laboratories, operational in 1946. Only two machines were built: first one was installed at National Advisory Committee for Aeronautics (NACA, later NASA), the second (1947) at the US Army’s Ballistic Research Laboratory (BRL). Construction Design was started in 1944. The tape-controlled (Harvard architecture) machine had two (design allowed for a total of six) processors ("computers") that could operate independently, an early form of multiprocessing. Weighed about . Significance * Inspired Richard Hamming to investigate the automatic error-correction, which led to invention of Hamming codes * One of the early electromechanical general purpose computers * First American machine and first George Stibitz design to use floating-point arithmetic *Had an early form of multiprocessing *Had a very primitive form of an operating system, albeit in har ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromechanical Computer
A mechanical computer is a computer built from mechanical components such as levers and gears rather than electronic components. The most common examples are adding machines and mechanical counters, which use the turning of gears to increment output displays. More complex examples could carry out multiplication and division—Friden used a moving head which paused at each column—and even differential analysis. One model, the Ascota 170 accounting machine sold in the 1960s calculated square roots. Mechanical computers can be either analog, using smooth mechanisms such as curved plates or slide rules for computations; or digital, which use gears. Mechanical computers reached their zenith during World War II, when they formed the basis of complex bombsights including the Norden, as well as the similar devices for ship computations such as the US Torpedo Data Computer or British Admiralty Fire Control Table. Noteworthy are mechanical flight instruments for early spacecraft, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Defense Research Committee
The National Defense Research Committee (NDRC) was an organization created "to coordinate, supervise, and conduct scientific research on the problems underlying the development, production, and use of mechanisms and devices of warfare" in the United States from June 27, 1940, until June 28, 1941. Most of its work was done with the strictest secrecy, and it began research of what would become some of the most important technology during World War II, including radar and the atomic bomb. It was superseded by the Office of Scientific Research and Development in 1941, and reduced to merely an advisory organization until it was eventually terminated during 1947. Organization The NDRC was created by an order of President Franklin Delano Roosevelt on June 27, 1940. It was part of the Council of National Defense, which had been created during 1916 to coordinate industry and resources for national security purposes. Vannevar Bush, the director of the Carnegie Institution, had pressed for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analog Device
Analog devices are a combination of both analog machine and analog media that can together measure, record, reproduce, receive or broadcast continuous information, for example, the almost infinite number of grades of transparency, voltage, resistance, rotation, or pressure. In theory, the continuous information in an analog signal has an infinite number of possible values with the only limitation on resolution being the accuracy of the analog device. Analog media are materials with analog properties, such as photographic film, which are used in analog devices, such as cameras. Example devices Non-electrical There are notable non-electrical analog devices, such as some clocks (sundials, water clocks), the astrolabe, slide rules, the governor of a steam engine, the planimeter (a simple device that measures the surface area of a closed shape), Kelvin's mechanical tide predictor, acoustic rangefinders, servomechanisms (e.g. the thermostat), a simple mercury thermometer, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Teleprinter
A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Initially they were used in telegraphy, which developed in the late 1830s and 1840s as the first use of electrical engineering, though teleprinters were not used for telegraphy until 1887 at the earliest. The machines were adapted to provide a user interface to early mainframe computers and minicomputers, sending typed data to the computer and printing the response. Some models could also be used to create punched tape for data storage (either from typed input or from data received from a remote source) and to read back such tape for local printing or transmission. Teleprinters could use a variety of different communication media. These included a simple pair of wires; dedicated non-switched telephone circuits (leased lines); switched network ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dartmouth College
Dartmouth College (; ) is a private research university in Hanover, New Hampshire. Established in 1769 by Eleazar Wheelock, it is one of the nine colonial colleges chartered before the American Revolution. Although founded to educate Native Americans in Christian theology and the English way of life, the university primarily trained Congregationalist ministers during its early history before it gradually secularized, emerging at the turn of the 20th century from relative obscurity into national prominence. It is a member of the Ivy League. Following a liberal arts curriculum, Dartmouth provides undergraduate instruction in 40 academic departments and interdisciplinary programs, including 60 majors in the humanities, social sciences, natural sciences, and engineering, and enables students to design specialized concentrations or engage in dual degree programs. In addition to the undergraduate faculty of arts and sciences, Dartmouth has four professional and graduate schools: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Mathematical Society
The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, advocacy and other programs. The society is one of the four parts of the Joint Policy Board for Mathematics and a member of the Conference Board of the Mathematical Sciences. History The AMS was founded in 1888 as the New York Mathematical Society, the brainchild of Thomas Fiske, who was impressed by the London Mathematical Society on a visit to England. John Howard Van Amringe was the first president and Fiske became secretary. The society soon decided to publish a journal, but ran into some resistance, due to concerns about competing with the American Journal of Mathematics. The result was the ''Bulletin of the American Mathematical Society'', with Fiske as editor-in-chief. The de facto journal, as intended, was influential in in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
