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German Weather Ship Lauenburg
''Lauenburg'' was a German weather ship used in the early years of the Second World War to provide weather reports for German shipping, particularly German U-boats. After the German use of such vessels had been identified as a weakness that could be exploited to break the Enigma code, ''Lauenburg'' was captured and sunk on 28 June 1941. The Royal Navy acquired important German code books and parts of an Enigma machine. Early life ''Lauenburg'' had been built in 1938 as a fishing trawler, named after the town of Lauenburg, and with the identification number 'PG 532'. She operated out of Geestemünde for her owners, H. Bischoff & Co, of Bremen. She was acquired by the '' Kriegsmarine'' in 1940, and entered naval service in November, having been converted into a weather ship, retaining the name ''Lauenburg''. In her new guise she carried a crew of between 19 and 21, as well as eight meteorologists. She was to be used to provide detailed weather reports for naval units, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HMS Tartar (F43)
HMS ''Tartar'' was a destroyer of the Royal Navy that saw service in most of the naval theatres of World War II. She had an eventful career, eventually receiving the nickname 'Lucky Tartar' due to her numerous escapes from dangerous situations. She was one of only four from the sixteen Royal Navy-operated Tribal-class destroyers to survive the war. Description The Tribals were intended to counter the large destroyers being built abroad and to improve the firepower of the existing destroyer flotillas and were thus significantly larger and more heavily armed than the preceding . The ships displaced at standard load and at deep load. They had an overall length of , a beam of Lenton, p. 165 and a draught of .English, p. 12 The destroyers were powered by two Parsons geared steam turbines, each driving one propeller shaft using steam provided by three Admiralty three-drum boilers. The turbines developed a total of and gave a maximum speed of . During her sea trials ''Tartar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptologist
This is a list of cryptographers. Cryptography is the practice and study of techniques for secure communication in the presence of third parties called adversaries. Pre twentieth century * Al-Khalil ibn Ahmad al-Farahidi: wrote a (now lost) book on cryptography titled the "''Book of Cryptographic Messages''". * Al-Kindi, 9th century Arabic polymath and originator of frequency analysis. * Athanasius Kircher, attempts to decipher crypted messages * Augustus the Younger, Duke of Brunswick-Lüneburg, wrote a standard book on cryptography * Ibn Wahshiyya: published several cipher alphabets that were used to encrypt magic formulas. * John Dee, wrote an occult book, which in fact was a cover for crypted text * Ibn 'Adlan: 13th-century cryptographer who made important contributions on the sample size of the frequency analysis. * Duke of Mantua Francesco I Gonzaga is the one who used the earliest example of homophonic Substitution cipher in early 1400s. * Ibn al-Durayhim: gave detailed d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auxiliary Ships Of The Kriegsmarine
Auxiliary may refer to: * A backup site or system In language * Auxiliary language (other) * Auxiliary verb In military and law enforcement * Auxiliary police * Auxiliaries, civilians or quasi-military personnel who provide support of some kind to a military service ** Auxiliaries (Roman military) In religion * Auxiliary bishop, in the Roman Catholic Church * Auxiliary organization (LDS Church) In technology * Auxiliary input jack and auxiliary cable, generally for audio; frequently associated with mobile device audio * Aux-send of a mixing console * An auxiliary Port is a common port found on many Cisco routers for CLI access. Other uses * Auxiliary route, also known as "special route", in road transportation ** An auxiliary route of the Interstate Highway System in the United States * Auxiliary ship is a naval vessel designed to operate in support of combat ships and other naval operations * Auxiliary (fraternity or sorority) * A marching band color guard See als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Atlantic Weather War
The North Atlantic weather war occurred during World War II. The Allies (Britain in particular) and Germany tried to gain a monopoly on weather data in the North Atlantic and Arctic oceans. Meteorological intelligence was important as it affected military planning and the routing of ships and convoys. In some circumstances, visibility was necessary (photographic reconnaissance and bombing raids) and in others concealment (keeping ship movements secret or suppressing enemy air activity). D-day planning was greatly affected by weather forecasting; it was delayed by one day in the expectation that a storm would blow out and sea conditions would be acceptable. British sources of data included ships at sea and the weather stations at Valentia Observatory and Blacksod Point, in neutral Ireland; German use of weather ships also exposed their secret Enigma codes. Ocean weather vessels In 1939, United States Coast Guard vessels were being used as weather ships to protect transatlan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptanalysis Of The Enigma
Cryptanalysis of the Enigma ciphering system enabled the western Allies in World War II to read substantial amounts of Morse-coded radio communications of the Axis powers that had been enciphered using Enigma machines. This yielded military intelligence which, along with that from other decrypted Axis radio and teleprinter transmissions, was given the codename '' Ultra''. The Enigma machines were a family of portable cipher machines with rotor scramblers. Good operating procedures, properly enforced, would have made the plugboard Enigma machine unbreakable. However, most of the German military forces, secret services, and civilian agencies that used Enigma employed poor operating procedures, and it was these poor procedures that allowed the Enigma machines to be reverse-engineered and the ciphers to be read. The German plugboard-equipped Enigma became Nazi Germany's principal crypto-system. In December 1932 it was "broken" by mathematician Marian Rejewski at the Polish G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jan Mayen
Jan Mayen () is a Norwegian volcanic island in the Arctic Ocean with no permanent population. It is long (southwest-northeast) and in area, partly covered by glaciers (an area of around the Beerenberg volcano). It has two parts: larger northeast Nord-Jan and smaller Sør-Jan, linked by a wide isthmus. It lies northeast of Iceland (495 km 05 miNE of Kolbeinsey), east of central Greenland, and west of the North Cape, Norway. The island is mountainous, the highest summit being the Beerenberg volcano in the north. The isthmus is the location of the two largest lakes of the island, Sørlaguna (South Lagoon) and Nordlaguna (North Lagoon). A third lake is called Ullerenglaguna (Ullereng Lagoon). Jan Mayen was formed by the Jan Mayen hotspot and is defined by geologists as a separate continent. Although administered separately, in the ISO 3166-1 standard, Jan Mayen and Svalbard are collectively designated as ''Svalbard and Jan Mayen'', with the two-letter country code "SJ". N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lauenburg Torpedoed
Lauenburg (), or Lauenburg an der Elbe ( en, Lauenberg on the Elbe), is a town in the state of Schleswig-Holstein, Germany. It is situated on the northern bank of the river Elbe, east of Hamburg. It is the southernmost town of Schleswig-Holstein and belongs to the ''Kreis'' (district) of Herzogtum Lauenburg. History The town was founded in 1182 by Bernard of Ascania, the ancestor of the Dukes of Lauenburg. It took its name from that of the castle of ''Lowenborch'' (erected here between 1181 and 1182), deriving from ''Lave'', the Polabian-language name of the Elbe (compare modern Czech ''Labe''). Saxe-Lauenburg was a duchy until 1 July 1876, when it was incorporated into the Royal Prussian Province of Schleswig-Holstein. Lauenburg served as the ducal capital until 1616, when the castle burnt down. In 1619 the capital was moved to Ratzeburg. The area of the duchy was roughly identical with that of today's district. In medieval times Lauenburg was a waypoint on the Old Salt R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scapa Flow
Scapa Flow viewed from its eastern end in June 2009 Scapa Flow (; ) is a body of water in the Orkney Islands, Scotland, sheltered by the islands of Mainland, Graemsay, Burray,S. C. George, ''Jutland to Junkyard'', 1973. South Ronaldsay and Hoy. Its sheltered waters have played an important role in travel, trade and conflict throughout the centuries. Vikings anchored their longships in Scapa Flow more than a thousand years ago. It was the United Kingdom's chief naval base during the First and Second World Wars, but the facility was closed in 1956. Scapa Flow has a shallow sandy bottom not deeper than and most of it is about deep; it is one of the great natural harbours and anchorages of the world, with sufficient space to hold a number of navies. The harbour has an area of and contains just under 1 billion cubic metres of water. Since the scuttling of the German fleet after World War I, its wrecks and their marine habitats form an internationally acclaimed diving lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Destroyers
In navy, naval terminology, a destroyer is a fast, manoeuvrable, long-endurance warship intended to escort larger vessels in a Naval fleet, fleet, convoy or Carrier battle group, battle group and defend them against powerful short range attackers. They were originally developed in 1885 by Fernando Villaamil for the Spanish NavySmith, Charles Edgar: ''A short history of naval and marine engineering.'' Babcock & Wilcox, ltd. at the University Press, 1937, page 263 as a defense against torpedo boats, and by the time of the Russo-Japanese War in 1904, these "torpedo boat destroyers" (TBDs) were "large, swift, and powerfully armed torpedo boats designed to destroy other torpedo boats". Although the term "destroyer" had been used interchangeably with "TBD" and "torpedo boat destroyer" by navies since 1892, the term "torpedo boat destroyer" had been generally shortened to simply "destroyer" by nearly all navies by the First World War. Before World War II, destroyers were light vessels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Cruiser
A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to this smaller cruisers had been of the protected cruiser model, possessing armored decks only. While lighter and smaller than other contemporary ships they were still true cruisers, retaining the extended radius of action and self-sufficiency to act independently around the world. Through their history they served in a variety of roles, primarily as convoy escorts and destroyer command ships, but also as scouts and fleet support vessels for battle fleets. Origins and development The first small steam-powered cruisers were built for the British Royal Navy with HMS ''Mercury'' launched in 1878. Such second and third class protected cruisers evolved, gradually becoming faster, better armed and better protected. Germany took a lead in small crui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bigram
A bigram or digram is a sequence of two adjacent elements from a string of tokens, which are typically letters, syllables, or words. A bigram is an ''n''-gram for ''n''=2. The frequency distribution of every bigram in a string is commonly used for simple statistical analysis of text in many applications, including in computational linguistics, cryptography, speech recognition, and so on. ''Gappy bigrams'' or ''skipping bigrams'' are word pairs which allow gaps (perhaps avoiding connecting words, or allowing some simulation of dependencies, as in a dependency grammar). ''Head word bigrams'' are gappy bigrams with an explicit dependency relationship. Details Bigrams help provide the conditional probability of a token given the preceding token, when the relation of the conditional probability is applied: P(W_n, W_) = That is, the probability P() of a token W_n given the preceding token W_ is equal to the probability of their bigram, or the co-occurrence of the two tokens P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its surrounding areas) is home to over 65% of the population. Iceland is the biggest part of the Mid-Atlantic Ridge that rises above sea level, and its central volcanic plateau is erupting almost constantly. The interior consists of a plateau characterised by sand and lava fields, mountains, and glaciers, and many glacial rivers flow to the sea through the lowlands. Iceland is warmed by the Gulf Stream and has a temperate climate, despite a high latitude just outside the Arctic Circle. Its high latitude and marine influence keep summers chilly, and most of its islands have a polar climate. According to the ancient manuscript , the settlement of Iceland began in 874 AD when the Norwegian chieftain Ingólfr Arnarson became the first p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
