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Royal Radar Establishment
The Royal Radar Establishment was a research centre in Malvern, Worcestershire in the United Kingdom. It was formed in 1953 as the Radar Research Establishment by the merger of the Air Ministry's Telecommunications Research Establishment (TRE) and the British Army's Radar Research and Development Establishment (RRDE). It was given its new name after a visit by Queen Elizabeth II in 1957. Both names were abbreviated to RRE. In 1976 the Signals Research and Development Establishment (SRDE), involved in communications research, joined the RRE to form the Royal Signals and Radar Establishment (RSRE). The two groups had been closely associated since before the opening of World War II, when the predecessor to RRDE was formed as a small group within the Air Ministry's research centre in Bawdsey Manor in Suffolk. Forced to leave Bawdsey due to its exposed location on the east coast of England, both groups moved several times before finally settling in separate locations in Malvern beginn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HIV Rev Response Element
The HIV-1 Rev response element (RRE) is a highly structured, ~350 nucleotide RNA segment present in the Env coding region of unspliced and partially spliced viral mRNAs. In the presence of the HIV-1 accessory protein Rev, HIV-1 mRNAs that contain the RRE can be exported from the nucleus to the cytoplasm for downstream events such as translation and virion packaging. RRE and HIV-1 biology Early phase The HIV-1 genome contains a single promoter and uses multiple reading frames and alternative splicing to encode 15 proteins from a single pre-mRNA species. Transcription from an integrated HIV-1 provirus generates a single 9 kilobase (kb) pre-mRNA containing multiple splice sites and nuclear retention signals. In the early phase of the viral life cycle, this pre-RNA is completely spliced to RRE-free, 2 kb messages. These smaller messages are then transported from the nucleus to the cytoplasm via standard mRNA nuclear export pathways (see Figure). One of these small, 2kb mess ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid State Physics
Solid-state physics is the study of rigid matter, or solids, through methods such as quantum mechanics, crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics. Solid-state physics studies how the large-scale properties of solid materials result from their atomic-scale properties. Thus, solid-state physics forms a theoretical basis of materials science. It also has direct applications, for example in the technology of transistors and semiconductors. Background Solid materials are formed from densely packed atoms, which interact intensely. These interactions produce the mechanical (e.g. hardness and elasticity), thermal, electrical, magnetic and optical properties of solids. Depending on the material involved and the conditions in which it was formed, the atoms may be arranged in a regular, geometric pattern ( crystalline solids, which include metals and ordinary water ice) or irregularly (an amorphous solid such as common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christchurch, Dorset
Christchurch () is a town and civil parish in Dorset on the south coast of England. The town had a population of 31,372 in 2021. For the borough the population was 48,368. It adjoins Bournemouth to the west, with the New Forest to the east. Part of the Historic counties of England, historic county of Hampshire, Christchurch was a Borough status in the United Kingdom, borough within the administrative county of Dorset from 1974 until 2019, when it became part of the new Bournemouth, Christchurch and Poole unitary authority. Founded in the seventh century at the confluence of the rivers River Avon (Hampshire), Avon and River Stour, Dorset, Stour which flow into Christchurch Harbour, the town was originally named Twynham but became known as Christchurch following the construction of the Christchurch Priory, priory in 1094. The town developed into an important trading port, and was Burh, fortified in the 9th century. Further defences were added in the 12th century with the constructio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dundee
Dundee (; sco, Dundee; gd, Dùn Dè or ) is Scotland's fourth-largest city and the 51st-most-populous built-up area in the United Kingdom. The mid-year population estimate for 2016 was , giving Dundee a population density of 2,478/km2 or 6,420/sq mi, the second-highest in Scotland. It lies within the eastern central Lowlands on the north bank of the Firth of Tay, which feeds into the North Sea. Under the name of Dundee City, it forms one of the 32 council areas used for local government in Scotland. Within the boundaries of the historic county of Angus, the city developed into a burgh in the late 12th century and established itself as an important east coast trading port. Rapid expansion was brought on by the Industrial Revolution, particularly in the 19th century when Dundee was the centre of the global jute industry. This, along with its other major industries, gave Dundee its epithet as the city of "jute, jam and journalism". Today, Dundee is promoted as "One City, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proximity Fuse
A proximity fuze (or fuse) is a Fuze (munitions), fuze that detonates an Explosive material, explosive device automatically when the distance to the target becomes smaller than a predetermined value. Proximity fuzes are designed for targets such as planes, missiles, ships at sea, and ground forces. They provide a more sophisticated trigger mechanism than the common contact fuze or timed fuze. It is estimated that it increases the lethality by 5 to 10 times, compared to these other fuzes. Background Before the invention of the proximity fuze, detonation was induced by direct contact, a timer set at launch or an altimeter. All of these earlier methods have disadvantages. The probability of a direct hit on a small moving target is low; a shell that just misses the target will not explode. A time- or height-triggered fuze requires good prediction by the gunner and accurate timing by the fuze. If either is wrong, then even accurately aimed shells may explode harmlessly before reaching ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-aircraft Artillery
Anti-aircraft warfare, counter-air or air defence forces is the battlespace response to aerial warfare, defined by NATO as "all measures designed to nullify or reduce the effectiveness of hostile air action".AAP-6 It includes surface based, subsurface ( submarine launched), and air-based weapon systems, associated sensor systems, command and control arrangements, and passive measures (e.g. barrage balloons). It may be used to protect naval, ground, and air forces in any location. However, for most countries, the main effort has tended to be homeland defence. NATO refers to airborne air defence as counter-air and naval air defence as anti-aircraft warfare. Missile defence is an extension of air defence, as are initiatives to adapt air defence to the task of intercepting any projectile in flight. In some countries, such as Britain and Germany during the Second World War, the Soviet Union, and modern NATO and the United States, ground-based air defence and air defence aircraft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orfordness
Orford Ness is a cuspate foreland shingle spit on the Suffolk coast in Great Britain, linked to the mainland at Aldeburgh and stretching along the coast to Orford and down to North Weir Point, opposite Shingle Street. It is divided from the mainland by the River Alde, and was formed by longshore drift along the coast. The material of the spit comes from places further north, such as Dunwich. Near the middle point of its length, at the foreland point or 'Ness', once stood Orfordness Lighthouse, demolished in summer 2020 owing to the encroaching sea. In the name of the lighthouse (and the radio transmitting station – see below), 'Orfordness' is written as one word. Description Orford Ness is an internationally important site for nature conservation. It contains a significant portion of the European reserve of vegetated shingle habitat, which is internationally scarce, highly fragile, and very easily damaged. Together with Havergate Island the site is a designated National Nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Death Ray
The death ray or death beam was a theoretical particle beam or electromagnetic weapon first theorized around the 1920s and 1930s. Around that time, notable inventors such as Guglielmo Marconi, Nikola Tesla, Harry Grindell Matthews, Edwin R. Scott, Erich Graichen and others claimed to have invented it independently. In 1957, the National Inventors Council was still issuing lists of needed military inventions that included a death ray. While based in fiction, research into energy-based weapons inspired by past speculation has contributed to real-life weapons in use by modern militaries sometimes called a sort of "death ray", such as the United States Navy and its Laser Weapon System (LaWS) deployed in mid-2014. Such armaments are technically known as directed-energy weapons. History In 1923, Edwin R. Scott, an inventor from San Francisco, claimed he was the first to develop a death ray that would destroy human life and bring down planes at a distance. He was born in Detroit, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert Watson-Watt
Sir Robert Alexander Watson Watt (13 April 1892 – 5 December 1973) was a Scottish pioneer of radio direction finding and radar technology. Watt began his career in radio physics with a job at the Met Office, where he began looking for accurate ways to track thunderstorms using the radio signals given off by lightning. This led to the 1920s development of a system later known as high-frequency direction finding (HFDF or "huff-duff"). Although well publicized at the time, the system's enormous military potential was not developed until the late 1930s. Huff-duff allowed operators to determine the location of an enemy radio in seconds and it became a major part of the network of systems that helped defeat the threat of German U-boats during World War II. It is estimated that huff-duff was used in about a quarter of all attacks on U-boats. In 1935 Watt was asked to comment on reports of a German death ray based on radio. Watt and his assistant Arnold Frederic Wilkins quickly dete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibre Optics
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths (data transfer rates) than electrical cables. Fibers are used instead of metal wires because signals travel along them with less loss; in addition, fibers are immune to electromagnetic interference, a problem from which metal wires suffer. Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in the case of a fiberscope. Specially designed fibers are also used for a variety of other applications, some of them being fiber optic sensors and fiber lasers. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guided Missiles
In military terminology, a missile is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously unguided rocket is made guided). Missiles have five system components: targeting, guidance system, flight system, engine and warhead. Missiles come in types adapted for different purposes: surface-to-surface and air-to-surface missiles (ballistic, cruise, anti-ship, anti-submarine, anti-tank, etc.), surface-to-air missiles (and anti-ballistic), air-to-air missiles, and anti-satellite weapons. Airborne explosive devices without propulsion are referred to as shells if fired by an artillery piece and bombs if dropped by an aircraft. Unguided jet- or rocket-propelled weapons are usually described as rocket artillery. Historically, the word ''missile'' referred to any projectile that is thrown, shot or propelled towards a target; this usage is still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Homing
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 flares beh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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