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Heat-seeker
Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it seamlessly. Missiles which use infrared seeking are often referred to as "heat-seekers" since infrared is radiated strongly by hot bodies. Many objects such as people, vehicle engines and aircraft generate and emit heat and so are especially visible in the infrared wavelengths of light compared to objects in the background. Infrared seekers are passive devices, which, unlike radar, provide no indication that they are tracking a target. That makes them suitable for sneak attacks during visual encounters or over longer ranges when they are used with a forward looking infrared or similar cuing system. Heat-seekers are extremely effective: 90% of all United States air combat losses over the past 25 years have been caused by infrared-homing missiles. They are, however, subject to a number of simple countermeasures, most notably by dropping flare ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IRIS-T Air-to-air-missile
The IRIS-T ("InfraRed Imaging System Tail/ Thrust Vector-Controlled") is a medium range infrared homing missile available in both air-to-air and ground defence surface-to-air variants. The missile was developed in the late 1990s–early 2000s by a German-led program to develop a short to medium range infrared homing air-to-air missile to replace the AIM-9 Sidewinder in use by some NATO member countries at the time. A goal of the program was for any aircraft capable of firing the Sidewinder to also be capable of launching the IRIS-T. The air-to-air variant was fielded in 2005. Surface-to-air defence systems variants came later, with the short-range IRIS-T SLS fielded in 2015, and the medium-range IRIS-T SLM fielded in 2022. One IRIS-T SLM battery, as supplied by Germany to Ukraine, consists of three truck-mounted launchers, carrying eight missiles each (with a range of ), and a separate command vehicle that can be positioned up to away. The command vehicle integrates multipl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-tank Missile
An anti-tank guided missile (ATGM), anti-tank missile, anti-tank guided weapon (ATGW) or anti-armor guided weapon is a Missile guidance, guided missile primarily designed to hit and destroy Armoured fighting vehicle, heavily armored military vehicles. ATGMs range in size from shoulder-launched weapons, which can be transported by a single soldier, to larger tripod-mounted weapons, which require a squad or team to transport and fire, to vehicle and aircraft mounted missile systems. Earlier man-portable anti-tank weapons like anti-tank rifles and magnetic anti-tank mines, generally had very short range, sometimes on the order of metres or tens of metres. Rocket-propelled high-explosive anti-tank (HEAT) systems appeared in World War II and extended range to the order of hundreds of metres, but accuracy was low and hitting targets at these ranges was largely a matter of luck. It was the combination of rocket propulsion and remote wire guidance that made the ATGM much more effective ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caesium
Caesium (IUPAC spelling) (or cesium in American English) is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of , which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium and potassium. It is pyrophoric and reacts with water even at . It is the least electronegative element, with a value of 0.79 on the Pauling scale. It has only one stable isotope, caesium-133. Caesium is mined mostly from pollucite. The element has 40 known isotopes, making it, along with barium and mercury, one of the elements with the most isotopes. Caesium-137, a fission product, is extracted from waste produced by nuclear reactors. The German chemist Robert Bunsen and physicist Gustav Kirchhoff discovered caesium in 1860 by the newly developed method of flame spectroscopy. The first small-scale applications for caesium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc Refining (metallurgy), refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes bimetallism, alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of its active battle fleet alone exceeding the next 13 navies combined, including 11 allies or partner nations of the United States as of 2015. It has the highest combined battle fleet tonnage (4,635,628 tonnes as of 2019) and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction, and five other carriers planned. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the United States Navy is the third largest of the United States military service branches in terms of personnel. It has 290 deployable combat vessels and more than 2,623 operational aircraft . The United States Navy traces its origins to the Continental Navy, which was established during the American Revolut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Movietone Sound System
The Movietone sound system is an optical sound-on-film method of recording sound for motion pictures that guarantees synchronization between sound and picture. It achieves this by recording the sound as a variable-density optical track on the same strip of film that records the pictures. The initial version was capable of a frequency response of 8500 Hz. Although sound films today use variable-area tracks, any modern motion picture theater (excluding those that have transitioned to digital cinema) can play a Movietone film without modification to the projector (though if the projector's sound unit has been fitted with red LED or laser light sources, the reproduction quality from a variable density track will be significantly impaired). Movietone was one of four motion picture sound systems under development in the U.S. during the 1920s, the others being DeForest Phonofilm, Warner Brothers' Vitaphone, and RCA Photophone, though Phonofilm was primarily an early version of Movietone. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theodore Case
Theodore Willard Case (December 12, 1888 – May 13, 1944) was an American chemist and inventor known for the invention of the Movietone sound-on-film system. Early life and education Theodore Willard Case was born in 1888 in Auburn, New York to Willard Erastus Case (1857 – 1918) and Eva Fidelia Caldwell Case (1857 – 1952). He attended a few boarding schools as a young man including The Manlius School near Syracuse, New York and Cloyne House School in Newport, Rhode Island He also attended the St. Paul School in Concord, New Hampshire to finish out his secondary education. Following his high school graduation he attended Yale University from 1908 to 1912, where he earned his B.A in Chemistry. He then attended Harvard University where he studied law. He did not find this as fulfilling as pursuing science so he left after about a year. During the years prior to opening the Case Research Lab he worked with his father in laboratories setup in the basements of their fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jagadish Chandra Bose
Sir Jagadish Chandra Bose (;, ; 30 November 1858 – 23 November 1937) was a biologist, physicist, Botany, botanist and an early writer of science fiction. He was a pioneer in the investigation of radio microwave optics, made significant contributions to botany, and was a major force behind the expansion of experimental science on the Indian subcontinent. Bose is considered the father of Bengali science fiction. He invented the crescograph, a device for measuring the growth of plants. Bose (crater), A crater on the moon was named in his honour. He founded Bose Institute, a premier research institute in India and also one of its oldest. Established in 1917, the institute was the first interdisciplinary research centre in Asia. He served as the Director of Bose Institute from its inception until his death. Born in Munshiganj, Bengal Presidency, during British India, British governance of India (now in Bangladesh), Bose graduated from St. Xavier's College, Calcutta (now Kolkata, W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indian People
Indians or Indian people are the Indian nationality law, citizens and nationals of India. In 2022, the population of India stood at over 1.4 billion people, making it the world's List of countries and dependencies by population, second-most populous country, containing 17.7 percent of the global population. In addition to the Indian population, the Non-resident Indian and Overseas Citizen of India, Indian overseas diaspora also boasts large numbers, particularly in the Arab states of the Persian Gulf and the Western world. While the demonym "Indian" applies to people originating from the present-day Republic of India, it was also formerly used as the identifying term for people originating from Pakistan and Bangladesh during British Raj, British colonial era until 1947. Particularly in North America, the terms "Asian Indian" and "East Indian" are sometimes used to differentiate Indians from the indigenous peoples of the Americas; although the Native American name controversy, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron
The electron ( or ) is a subatomic particle with a negative one elementary electric charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. The electron's mass is approximately 1/1836 that of the proton. Quantum mechanical properties of the electron include an intrinsic angular momentum ( spin) of a half-integer value, expressed in units of the reduced Planck constant, . Being fermions, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle. Like all elementary particles, electrons exhibit properties of both particles and waves: They can collide with other particles and can be diffracted like light. The wave properties of electrons are easier to observe with experiments than those of other particles like neutrons and protons because electrons have a lower mass and hence a longer de Broglie wavele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
