|
Wilhelm Cauer
Wilhelm Cauer (24 June 1900 – 22 April 1945) was a German mathematician and scientist. He is most noted for his work on the analysis and synthesis of electrical filters and his work marked the beginning of the field of network synthesis. Prior to his work, electronic filter design used techniques which accurately predicted filter behaviour only under unrealistic conditions. This required a certain amount of experience on the part of the designer to choose suitable sections to include in the design. Cauer placed the field on a firm mathematical footing, providing tools that could produce exact solutions to a given specification for the design of an electronic filter. Cauer initially specialised in general relativity but soon switched to electrical engineering. His work for a German subsidiary of the Bell Telephone Company brought him into contact with leading American engineers in the field of filters. This proved useful when Cauer was unable to feed his children during the G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berlin
Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constituent states, Berlin is surrounded by the State of Brandenburg and contiguous with Potsdam, Brandenburg's capital. Berlin's urban area, which has a population of around 4.5 million, is the second most populous urban area in Germany after the Ruhr. The Berlin-Brandenburg capital region has around 6.2 million inhabitants and is Germany's third-largest metropolitan region after the Rhine-Ruhr and Rhine-Main regions. Berlin straddles the banks of the Spree, which flows into the Havel (a tributary of the Elbe) in the western borough of Spandau. Among the city's main topographical features are the many lakes in the western and southeastern boroughs formed by the Spree, Havel and Dahme, the largest of which is Lake Müggelsee. Due to its l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battle Of Berlin
The Battle of Berlin, designated as the Berlin Strategic Offensive Operation by the Soviet Union, and also known as the Fall of Berlin, was one of the last major offensives of the European theatre of World War II. After the Vistula–Oder Offensive of January–February 1945, the Red Army had temporarily halted on a line east of Berlin. On 9 March, Germany established its defence plan for the city with Operation Clausewitz. The first defensive preparations at the outskirts of Berlin were made on 20 March, under the newly appointed commander of Army Group Vistula, General Gotthard Heinrici. When the Soviet offensive resumed on 16 April, two Soviet fronts (army groups) attacked Berlin from the east and south, while a third overran German forces positioned north of Berlin. Before the main battle in Berlin commenced, the Red Army encircled the city after successful battles of the Seelow Heights and Halbe. On 20 April 1945, Hitler's birthday, the 1st Belorussian Front ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richard Courant
Richard Courant (January 8, 1888 – January 27, 1972) was a German American mathematician. He is best known by the general public for the book '' What is Mathematics?'', co-written with Herbert Robbins. His research focused on the areas of real analysis, mathematical physics, the calculus of variations and partial differential equations. He wrote textbooks widely used by generations of students of physics and mathematics. He is also known for founding the institute now bearing his name. Life and career Courant was born in Lublinitz, in the Prussian Province of Silesia. His parents were Siegmund Courant and Martha Courant ''née'' Freund of Oels. Edith Stein was Richard's cousin on the paternal side. During his youth his parents moved often, including to Glatz, then to Breslau and in 1905 to Berlin. He stayed in Breslau and entered the university there, then continued his studies at the University of Zürich and the University of Göttingen. He became David Hilbert's assist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ronald M
Ronald is a masculine given name derived from the Old Norse ''Rögnvaldr'', Hanks; Hardcastle; Hodges (2006) p. 234; Hanks; Hodges (2003) § Ronald. or possibly from Old English '' Regenweald''. In some cases ''Ronald'' is an Anglicised form of the Gaelic ''Raghnall'', a name likewise derived from ''Rögnvaldr''. The latter name is composed of the Old Norse elements ''regin'' ("advice", "decision") and ''valdr'' ("ruler"). ''Ronald'' was originally used in England and Scotland, where Scandinavian influences were once substantial, although now the name is common throughout the English-speaking world. A short form of ''Ronald'' is ''Ron''. Pet forms of ''Ronald'' include ''Roni'' and ''Ronnie''. ''Ronalda'' and ''Rhonda'' are feminine forms of ''Ronald''. '' Rhona'', a modern name apparently only dating back to the late nineteenth century, may have originated as a feminine form of ''Ronald''. Hanks; Hardcastle; Hodges (2006) pp. 230, 408; Hanks; Hodges (2003) § Rhona. The names ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Otto Zobel
Otto Julius Zobel (October 20, 1887 – January 1970) was an electrical engineer who worked for the American Telephone & Telegraph Company (AT&T) in the early part of the 20th century. Zobel's work on filter design was revolutionary and led, in conjunction with the work of John R. Carson, to significant commercial advances for AT&T in the field of frequency-division multiplex (FDM) telephone transmissions.Bray, p. 62. Although much of Zobel's work has been superseded by more modern filter designs, it remains the basis of filter theory and his papers are still referenced today. Zobel invented the m-derived filterWhite, G"The Past" ''BT Technology Journal'', Vol 18, No 1, pp. 107–132, January 2000 . and the constant-resistance filter,Zobel, O J, ''Distortion Compensator'', , filed 26 June 1924, issued 12 Feb 1929. which remains in use. Zobel and Carson helped to establish the nature of noise in electric circuits, concluding that—contrary to mainstream belief—it is no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Ashley Campbell
George Ashley Campbell (November 27, 1870 – November 10, 1954) was an American engineer. He was a pioneer in developing and applying quantitative mathematical methods to the problems of long-distance telegraphy and telephony. His most important contributions were to the theory and implementation of the use of loading coils and the first wave filters designed to what was to become known as the image method. Both these areas of work resulted in important economic advantages for the American Telephone and Telegraph Company (AT&T). Education Campbell was educated at the McCollom Institute in New Hampshire and then at MIT, where he graduated in 1891. He then received a master's degree from Harvard University in 1893. He was awarded a fellowship which enabled him to spend three years on graduate work; one year studying advanced mathematics under Felix Klein at Göttingen, one year studying electricity and mechanics under Ludwig Boltzmann in Vienna, and one year studying under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Labs
Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by multinational company Nokia. With headquarters located in Murray Hill, New Jersey, the company operates several laboratories in the United States and around the world. Researchers working at Bell Laboratories are credited with the development of radio astronomy, the transistor, the laser, the photovoltaic cell, the charge-coupled device (CCD), information theory, the Unix operating system, and the programming languages B, C, C++, S, SNOBOL, AWK, AMPL, and others. Nine Nobel Prizes have been awarded for work completed at Bell Laboratories. Bell Labs had its origin in the complex corporate organization of the Bell System telephone conglomerate. In the late 19th century, the laboratory began as the Western Electric Engineering Department, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AT&T Corp
AT&T Inc. is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the world's largest telecommunications company by revenue and the third largest provider of mobile telephone services in the U.S. , AT&T was ranked 13th on the ''Fortune'' 500 rankings of the largest United States corporations, with revenues of $168.8 billion. During most of the 20th century, AT&T had a monopoly on phone service in the United States. The company began its history as the American District Telegraph Company, formed in St. Louis in 1878. After expanding services to Arkansas, Kansas, Oklahoma and Texas, through a series of mergers, it became Southwestern Bell Telephone Company in 1920, which was then a subsidiary of American Telephone and Telegraph Company. The latter was a successor of the original Bell Telephone Company founded by Alexander Graham Bell in 1877. The American Bell Telephone Company formed the American Telep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mix & Genest
Mix & Genest was founded on 1 October 1879 by the businessman Wilhelm Mix and the engineer Werner Genest in Berlin-Schöneberg. The company was initially an 1879 branch of the ITT Corporation. It was very successful and became one of the pioneers in low voltage devices. Among the products were devices for telephony and telegraphy. By 1904 the company had already 2300 employees and subsidiaries in London and Amsterdam. In 1920 AEG Allgemeine Elektricitäts-Gesellschaft AG (AEG; ) was a German producer of electrical equipment founded in Berlin as the ''Deutsche Edison-Gesellschaft für angewandte Elektricität'' in 1883 by Emil Rathenau. During the Second World War, AEG ... bought the majority of the stock shares. Mix & Genest was acquired by the ITT Corporation in 1930. The name Mix & Genest was dropped in 1958. References Bibliography * —Festschrift 75 Jahre Mix & Genest 1879–1954. Mix-und-Genest-Aktiengesellschaft Stuttgart, Stuttgart-Zuffenhausen 1954. External ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Von Laue
Max Theodor Felix von Laue (; 9 October 1879 – 24 April 1960) was a German physicist who received the Nobel Prize in Physics in 1914 for his discovery of the diffraction of X-rays by crystals. In addition to his scientific endeavors with contributions in optics, crystallography, quantum theory, superconductivity, and the theory of relativity, Laue had a number of administrative positions which advanced and guided German scientific research and development during four decades. A strong objector to Nazism, he was instrumental in re-establishing and organizing German science after World War II. Biography Early years Laue was born in Pfaffendorf, now part of Koblenz, Germany, to Julius Laue and Minna Zerrenner. In 1898, after passing his ''Abitur'' in Strassburg, he began his compulsory year of military service, after which in 1899 he started to study mathematics, physics, and chemistry at the University of Strassburg, the University of Göttingen, and the Ludwig Maximilian Uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fighting occurring throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia. An estimated 9 million soldiers were killed in combat, plus another 23 million wounded, while 5 million civilians died as a result of military action, hunger, and disease. Millions more died in genocides within the Ottoman Empire and in the 1918 influenza pandemic, which was exacerbated by the movement of combatants during the war. Prior to 1914, the European great powers were divided between the Triple Entente (comprising France, Russia, and Britain) and the Triple Alliance (containing Germany, Austria-Hungary, and Italy). Tensions in the Balkans came to a head on 28 June 1914, following the assassination of Archduke Franz Ferdin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geheimrat
''Geheimrat'' was the title of the highest advising officials at the Imperial, royal or princely courts of the Holy Roman Empire, who jointly formed the ''Geheimer Rat'' reporting to the ruler. The term remained in use during subsequent monarchic reigns in German-speaking areas of Europe until the end of the First World War. At its origin the literal meaning of the word in German was 'trusted advisor' - the word "geheim" (secret) implying that such an advisor could be trusted with the Monarch's secrets (similar to "secretary" in English being linguistically related to "secret"). The English-language equivalent is Privy Councillor. The office contributing to the state's politics and legislation had its roots in the age of absolutism from the 17th century onward, when a governmental administration by a dependent bureaucracy was established similar to the French '' Conseil du Roi''. A precursor was the '' Reichshofrat'', a judicial body established by Emperor Maximilian I of Habsbu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
