German Submarine U-571
German submarine ''U-571'' was a Type VIIC U-boat built for the ''Kriegsmarine'' of Nazi Germany for service during World War II. ''U-571'' conducted eleven war patrols, sinking five ships totalling , and damaging one other for 11,394 GRT. On 28 January 1944 she was attacked by an Australian-crewed Sunderland aircraft from No. 461 Squadron RAAF west of Ireland and was destroyed by depth charges. All hands were lost. The fictional 2000 U.S. war film '' ''U-571'''' has no relation to this U-boat, but is very loosely based on the British capture of and her Enigma and cipher keys. Design German Type VIIC submarines were preceded by the shorter Type VIIB submarines. ''U-571'' had a displacement of when at the surface and while submerged. She had a total length of , a pressure hull length of , a beam of , a height of , and a draught of . The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of for use while s ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Nazi Germany
Nazi Germany (lit. "National Socialist State"), ' (lit. "Nazi State") for short; also ' (lit. "National Socialist Germany") (officially known as the German Reich from 1933 until 1943, and the Greater German Reich from 1943 to 1945) was the German state between 1933 and 1945, when Adolf Hitler and the Nazi Party controlled the country, transforming it into a dictatorship. Under Hitler's rule, Germany quickly became a totalitarian state where nearly all aspects of life were controlled by the government. The Third Reich, meaning "Third Realm" or "Third Empire", alluded to the Nazi claim that Nazi Germany was the successor to the earlier Holy Roman Empire (800–1806) and German Empire (1871–1918). The Third Reich, which Hitler and the Nazis referred to as the Thousand-Year Reich, ended in May 1945 after just 12 years when the Allies defeated Germany, ending World War II in Europe. On 30 January 1933, Hitler was appointed chancellor of Germany, the head of gove ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Short Sunderland
The Short S.25 Sunderland is a British flying boat patrol bomber, developed and constructed by Short Brothers for the Royal Air Force (RAF). The aircraft took its service name from the town (latterly, city) and port of Sunderland in North East England. Developed in parallel with the civilian Short Empire, S.23 ''Empire'' flying boat, the flagship of Imperial Airways, the Sunderland was developed specifically to conform to the requirements of British Air Ministry List of Air Ministry specifications#1930.E2.80.931939, Specification R.2/33 for a long-range patrol/reconnaissance flying boat to serve with the Royal Air Force (RAF). As designed, it served as a successor to the earlier Short Sarafand flying boat. Sharing several similarities with the S.23, it featured a more advanced aerodynamic hull and was outfitted with various offensive and defensive armaments, including machine gun Gun turret#Aircraft, turrets, bombs, Parachute mine, aerial mines, and depth charges. The Sunderland ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such a device was called an automotive, automobile, locomotive, or fish torpedo; colloquially a ''fish''. The term ''torpedo'' originally applied to a variety of devices, most of which would today be called naval mine, mines. From about 1900, ''torpedo'' has been used strictly to designate a self-propelled underwater explosive device. While the 19th-century battleship had evolved primarily with a view to engagements between armored warships with naval artillery, large-caliber guns, the invention and refinement of torpedoes from the 1860s onwards allowed small torpedo boats and other lighter surface combatant , surface vessels, submarines/submersibles, even improvised fishing boats or frogmen, and later light aircraft, to destroy large shi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Propeller
A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working fluid such as water or air. Propellers are used to pump fluid through a pipe or duct, or to create thrust to propel a boat through water or an aircraft through air. The blades are specially shaped so that their rotational motion through the fluid causes a pressure difference between the two surfaces of the blade by Bernoulli's principle which exerts force on the fluid. Most marine propellers are screw propellers with helical blades rotating on a propeller shaft (ship), propeller shaft with an approximately horizontal axis. History Early developments The principle employed in using a screw propeller is derived from sculling. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Motor–generator
A motor–generator (an M–G set) is a device for converting electrical power to another form. Motor–generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line. Large motor–generators were widely used to convert industrial amounts of power while smaller motor–generators (such as the one shown in the picture) were used to convert battery power to higher DC voltages. While a motor–generator set may consist of distinct motor and generator machines coupled together, a single unit dynamotor (for dynamo–motor) has the motor coils and the generator coils wound around a single rotor; both the motor and generator therefore share the same outer field coils or magnets.Radio Amateur's Handbook 1976, pub. [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Brown, Boveri & Cie
Brown, Boveri & Cie. (Brown, Boveri & Company; BBC) was a Swiss group of electrical engineering companies. It was founded in Zürich, in 1891 by Charles Eugene Lancelot Brown and Walter Boveri who worked at the Maschinenfabrik Oerlikon. In 1970 BBC took over the Maschinenfabrik Oerlikon. In 1988 it merged with ASEA to form ABB. Early History of BBC Brown Boveri BBC Brown Boveri was established in 1891. The company was one of only a few multinational corporations to operate subsidiaries that were larger than the parent company. Because of the limitations of the Swiss domestic market, Brown Boveri established subsidiaries throughout Europe relatively early in its history, and at times had difficulty maintaining managerial control over some of its larger operating units. The merger with ASEA, a company which was praised for its strong management, was expected to help Brown Boveri reorganize and reassert control over its vast international network. Activity in Britain Brown Bove ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Supercharged
In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induction that is mechanically powered (usually by a belt from the engine's crankshaft), as opposed to a turbocharger, which is powered by the kinetic energy of the exhaust gasses. However, up until the mid-20th century, a turbocharger was called a "turbosupercharger" and was considered a type of supercharger. The first supercharged engine was built in 1878, with usage in aircraft engines beginning in the 1910s and usage in car engines beginning in the 1920s. In piston engines used by aircraft, supercharging was often used to compensate for the lower air density at high altitudes. Supercharging is less commonly used in the 21st century, as manufacturers have shifted to turbochargers to reduce fuel consumption and/or increase power outputs. Des ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Draught (ship)
The draft or draught of a ship's hull is the vertical distance between the waterline and the bottom of the hull (keel). The draught of the vessel is the maximum depth of any part of the vessel, including appendages such as rudders, propellers and drop keels if deployed. Draft determines the minimum depth of water a ship or boat can safely navigate. The related term air draft is the maximum height of any part of the vessel above the water. The more heavily a vessel is loaded, the deeper it sinks into the water, and the greater its draft. After construction, the shipyard creates a table showing how much water the vessel displaces based on its draft and the density of the water (salt or fresh). The draft can also be used to determine the weight of cargo on board by calculating the total displacement of water, accounting for the content of the ship's bunkers, and using Archimedes' principle. The closely related term "trim" is defined as the difference between the forward and aft ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Beam (nautical)
The beam of a ship is its width at its widest point. The maximum beam (BMAX) is the distance between planes passing through the outer extremities of the ship, beam of the hull (BH) only includes permanently fixed parts of the hull, and beam at waterline (BWL) is the maximum width where the hull intersects the surface of the water. Generally speaking, the wider the beam of a ship (or boat), the more initial stability it has, at the expense of secondary stability in the event of a capsize, where more energy is required to right the vessel from its inverted position. A ship that heels on her ''beam ends'' has her deck beams nearly vertical. Typical values Typical length-to-beam ratios ( aspect ratios) for small sailboats are from 2:1 (dinghies to trailerable sailboats around ) to 5:1 (racing sailboats over ). Large ships have widely varying beam ratios, some as large as 20:1. Rowing shells designed for flatwater racing may have length to beam ratios as high as 30:1, while a cor ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Key (cryptography)
A key in cryptography is a piece of information, usually a string of numbers or letters that are stored in a file, which, when processed through a cryptographic algorithm, can encode or decode cryptographic data. Based on the used method, the key can be different sizes and varieties, but in all cases, the strength of the encryption relies on the security of the key being maintained. A key’s security strength is dependent on its algorithm, the size of the key, the generation of the key, and the process of key exchange. Scope The key is what is used to encrypt data from plaintext to ciphertext. There are different methods for utilizing keys and encryption. Symmetric cryptography Symmetric cryptography refers to the practice of the same key being used for both encryption and decryption. Asymmetric cryptography Asymmetric cryptography has separate keys for encrypting and decrypting. These keys are known as the public and private keys, respectively. Purpose Since the key pro ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |