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Perforated Sheets
The method of Zygalski sheets was a cryptologic technique used by the Polish Cipher Bureau before and during World War II, and during the war also by British cryptologists at Bletchley Park, to decrypt messages enciphered on German Enigma machines. The Zygalski-sheet apparatus takes its name from Polish Cipher Bureau mathematician–cryptologist Henryk Zygalski, who invented it about October 1938. Method Zygalski's device comprised a set of 26 perforated sheets for each of the, initially, six possible sequences for inserting the three rotors into the Enigma machine's scrambler. Each sheet related to the starting position of the left (slowest-moving) rotor. The 26 × 26 matrix represented the 676 possible starting positions of the middle and right rotors and was duplicated horizontally and vertically: ''a–z, a–y''. The sheets were punched with holes in the positions that would allow a "female" to occur. Polish mathematician–cryptologist Marian Rejewski writes about how ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plugboard
A plugboard or control panel (the term used depends on the application area) is an array of jack (connector), jacks or sockets (often called hubs) into which patch cords can be inserted to complete an electrical circuit. Control panels are sometimes used to direct the operation of unit record equipment, :Cryptographic hardware, cipher machines, and History of computing hardware#Digital computation, early computers. The array of holes is often contained in a flat removable panel that can be inserted into a machine and pressed against an array of contacts. This allows the machine to be quickly switched between different applications. The contacts on the machine are hard wired to the various devices that comprise the machine, such as relays, counters, inputs from each card reader column, outputs to a card punch column or printer position, and so on. The wiring on a plugboard connects these devices to perform a specific function, say reading cards and summing up the numbers punched ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alan Turing
Alan Mathison Turing (; 23 June 1912 – 7 June 1954) was an English mathematician, computer scientist, logician, cryptanalyst, philosopher and theoretical biologist. He was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science. Born in London, Turing was raised in southern England. He graduated from University of Cambridge, King's College, Cambridge, and in 1938, earned a doctorate degree from Princeton University. During World War II, Turing worked for the Government Code and Cypher School at Bletchley Park, Britain's codebreaking centre that produced Ultra (cryptography), Ultra intelligence. He led Hut 8, the section responsible for German naval cryptanalysis. Turing devised techniques for speeding the breaking of Germ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PC Bruno
''PC Bruno'' was a Polish– French–Spanish signals–intelligence station near Paris during World War II, from October 1939 until June 1940. Its function was decryption of cipher messages, most notably German messages enciphered on the Enigma machine. ''PC Bruno'' worked in close cooperation with Britain's decryption center at Bletchley Park. History In the early 1930s, French military intelligence acquired operation manuals and sample messages for the German Enigma cipher machine. French intelligence officer Captain Gustave Bertrand supplied this material to Poland's ''Biuro Szyfrów'' ("Cipher Bureau"), which used it as part of their successful effort to break Enigma. In July 1939 the ''Biuro Szyfrów'' gave French and British intelligence all their results. Both countries were expanding their decryption efforts in anticipation of war, and this continued after the war started in September 1939. When Poland was overrun by Germany and the Soviet Union, the key staff of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gordon Welchman
William Gordon Welchman OBE (15 June 1906 – 8 October 1985) was an English mathematician. During World War II, he worked at Britain's secret decryption centre at Bletchley Park, where he was one of the most important contributors. In 1948, after the war, he moved to the US and later worked on the design of military communications systems. Early life, education and career Gordon Welchman was born, the youngest of three children, at Fishponds in Bristol, to William Welchman (1866–1954) and Elizabeth Marshall Griffith. William was a Church of England priest who had been a missionary overseas before returning to England as a country vicar, eventually becoming archdeacon of Bristol. Elizabeth was the daughter of another priest, the Revd Edward Moule Griffith. Welchman was educated at Marlborough College and then studied mathematics at Trinity College, Cambridge, from 1925 to 1928. In 1929, he became a Research Fellow in Mathematics at Sidney Sussex College, Cambridge. He be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John R
John R. (born John Richbourg, August 20, 1910 – February 15, 1986) was an American radio disc jockey who attained fame in the 1950s and 1960s for playing rhythm and blues music on Nashville radio station WLAC. He was also a notable record producer and artist manager. Richbourg was arguably the most popular and charismatic of the four announcers at WLAC who showcased popular African-American music in nightly programs from the late 1940s to the early 1970s. (The other three were Gene Nobles, Herman Grizzard, and Bill "Hoss" Allen.) Later rock music disc jockeys, such as Alan Freed and Wolfman Jack, mimicked Richbourg's practice of using speech that simulated African-American street language of the mid-twentieth century. Richbourg's highly stylized approach to on-air presentation of both music and advertising earned him popularity, but it also created identity confusion. Because Richbourg and fellow disc jockey Allen used African-American speech patterns, many listeners thought t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
England
England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It shares Anglo-Scottish border, a land border with Scotland to the north and England–Wales border, another land border with Wales to the west, and is otherwise surrounded by the North Sea to the east, the English Channel to the south, the Celtic Sea to the south-west, and the Irish Sea to the west. Continental Europe lies to the south-east, and Ireland to the west. At the 2021 United Kingdom census, 2021 census, the population was 56,490,048. London is both List of urban areas in the United Kingdom, the largest city and the Capital city, capital. The area now called England was first inhabited by modern humans during the Upper Paleolithic. It takes its name from the Angles (tribe), Angles, a Germanic peoples, Germanic tribe who settled du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Western Europe, with a population of 14.9 million. London stands on the River Thames in southeast England, at the head of a tidal estuary down to the North Sea, and has been a major settlement for nearly 2,000 years. Its ancient core and financial centre, the City of London, was founded by the Roman Empire, Romans as Londinium and has retained its medieval boundaries. The City of Westminster, to the west of the City of London, has been the centuries-long host of Government of the United Kingdom, the national government and Parliament of the United Kingdom, parliament. London grew rapidly 19th-century London, in the 19th century, becoming the world's List of largest cities throughout history, largest city at the time. Since the 19th cen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warsaw
Warsaw, officially the Capital City of Warsaw, is the capital and List of cities and towns in Poland, largest city of Poland. The metropolis stands on the Vistula, River Vistula in east-central Poland. Its population is officially estimated at 1.86 million residents within a Warsaw metropolitan area, greater metropolitan area of 3.27 million residents, which makes Warsaw the List of cities in the European Union by population within city limits, 6th most-populous city in the European Union. The city area measures and comprises List of districts and neighbourhoods of Warsaw, 18 districts, while the metropolitan area covers . Warsaw is classified as an Globalization and World Cities Research Network#Alpha 2, alpha global city, a major political, economic and cultural hub, and the country's seat of government. It is also the capital of the Masovian Voivodeship. Warsaw traces its origins to a small fishing town in Masovia. The city rose to prominence in the late 16th cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Britain
Great Britain is an island in the North Atlantic Ocean off the north-west coast of continental Europe, consisting of the countries England, Scotland, and Wales. With an area of , it is the largest of the British Isles, the List of European islands by area, largest European island, and the List of islands by area, ninth-largest island in the world. It is dominated by a maritime climate with narrow temperature differences between seasons. The island of Ireland, with an area 40 per cent that of Great Britain, is to the west – these islands, along with over List of islands of the British Isles, 1,000 smaller surrounding islands and named substantial rocks, comprise the British Isles archipelago. Connected to mainland Europe until 9,000 years ago by a land bridge now known as Doggerland, Great Britain has been inhabited by modern humans for around 30,000 years. In 2011, it had a population of about , making it the world's List of islands by population, third-most-populous islan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
France
France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlantic, North Atlantic, the French West Indies, and List of islands of France, many islands in Oceania and the Indian Ocean, giving it Exclusive economic zone of France, one of the largest discontiguous exclusive economic zones in the world. Metropolitan France shares borders with Belgium and Luxembourg to the north; Germany to the northeast; Switzerland to the east; Italy and Monaco to the southeast; Andorra and Spain to the south; and a maritime border with the United Kingdom to the northwest. Its metropolitan area extends from the Rhine to the Atlantic Ocean and from the Mediterranean Sea to the English Channel and the North Sea. Its Regions of France, eighteen integral regions—five of which are overseas—span a combined area of and hav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polish General Staff
Polish General Staff, formally known as the General Staff of the Polish Armed Forces ( Polish: ''Sztab Generalny Wojska Polskiego'') is the highest professional body within the Polish Armed Forces. Organizationally, it is an integral part of the Ministry of National Defence and the Chief of the General Staff is the highest ranking military officer at the Ministry. It was created in 1918, and was renamed the Main Staff (''Sztab Główny'') in 1928 before being reverted back to General Staff (''Sztab Generalny'') in 1945 by the Soviet backed Communist Government. Currently General Wiesław Kukuła holds the position of Chief of the General Staff of the Polish Armed Forces (''Szef Sztabu Generalnego Wojska Polskiego''). History and structure On 25 October 1918, a decision was made to establish the directorate of the chief of staff of the Polish Army. On 22 December 1928 the General Staff was renamed to the Main Staff (''Sztab Główny''). In September 1939, during the Invasion of Pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
