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Cloaking Devices
A cloaking device is a hypothetical or fictional stealth technology that can cause objects, such as spaceships or individuals, to be partially or wholly invisible to parts of the electromagnetic (EM) spectrum. Fictional cloaking devices have been used as plot devices in various media for many years. Developments in scientific research show that real-world cloaking devices can obscure objects from at least one wavelength of EM emissions. Scientists already use artificial materials called metamaterials to bend light around an object. However, over the entire spectrum, a cloaked object scatters more than an uncloaked object. Conceptual origins '' Star Trek'' screenwriter Paul Schneider, inspired in part by the 1958 film ''Run Silent, Run Deep,'' and in part by ''The Enemy Below,'' which had been released in 1957, imagined cloaking as a space-travel analog of a submarine submerging, and employed it in the 1966 ''Star Trek'' episode " Balance of Terror", in which he introduced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stealth Technology
Stealth technology, also termed low observable technology (LO technology), is a sub-discipline of military tactics and passive and active electronic countermeasures, which covers a range of methods used to make personnel, aircraft, ships, submarines, missiles, satellites, and ground vehicles less visible (ideally invisible) to radar, infrared, sonar and other detection methods. It corresponds to military camouflage for these parts of the electromagnetic spectrum (i.e., multi-spectral camouflage). Development of modern stealth technologies in the United States began in 1958, where earlier attempts to prevent radar tracking of its U-2 spy planes during the Cold War by the Soviet Union had been unsuccessful. Designers turned to developing a specific shape for planes that tended to reduce detection by redirecting electromagnetic radiation waves from radars. Radiation-absorbent material was also tested and made to reduce or block radar signals that reflect off the surfaces o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transporter (Star Trek)
A transporter is a fictional teleportation machine used in the '' Star Trek'' science fiction franchise. Transporters allow for teleportation by converting a person or object into an energy pattern (a process called "dematerialization"), then sending ("beaming") it to a target location or else returning it to the transporter, where it is reconverted into matter ("rematerialization"). Since its introduction in ''Star Trek: The Original Series'' in 1966, the name and similar concepts have made their way to other science fiction scenarios, in literature (such as the ''Thousand Cultures'' series), games (''SimEarth''), etc. The transporter was originally conceived as a device to convey characters from a starship to the surface of a planet without the need for expensive and time-consuming special effects to depict the starship or another craft physically landing. Malfunctioning transporters are also often used as a plot device to set up a variety of science fiction premises. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the battledress of a modern soldier, and the leaf-mimic katydid's wings. A third approach, motion dazzle, confuses the observer with a conspicuous pattern, making the object visible but momentarily harder to locate, as well as making general aiming easier. The majority of camouflage methods aim for crypsis, often through a general resemblance to the background, high contrast disruptive coloration, eliminating shadow, and countershading. In the open ocean, where there is no background, the principal methods of camouflage are transparency, silvering, and countershading, while the bioluminescence, ability to produce light is among other things used for counter-illumination on the undersides of cephalopods such as squid. Some animals, such as chamel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Camouflage
Active camouflage or adaptive camouflage is camouflage that adapts, often rapidly, to the surroundings of an object such as an animal or military vehicle. In theory, active camouflage could provide perfect concealment from visual detection. Active camouflage is used in several groups of animals, including reptiles on land, and cephalopod molluscs and flatfish in the sea. Animals achieve active camouflage both by Camouflage#Crypsis by changing skin pattern.2C colour, color change and (among marine animals such as squid) by counter-illumination, with the use of bioluminescence. Military counter-illumination camouflage was first investigated during the World War II, Second World War for marine use. More recent research has aimed to achieve crypsis by using cameras to sense the visible background, and by controlling Peltier panels or coatings that can vary their appearance. In animals Active camouflage is used in several groups of animals including cephalopod molluscs, fish, and r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
An Invisibility Cloak Using Optical Camouflage By Susumu Tachi
An, AN, aN, or an may refer to: Businesses and organizations * Airlinair (IATA airline code AN) * Alleanza Nazionale, a former political party in Italy * AnimeNEXT, an annual anime convention located in New Jersey * Anime North, a Canadian anime convention * Ansett Australia, a major Australian airline group that is now defunct (IATA designator AN) * Apalachicola Northern Railroad (reporting mark AN) 1903–2002 ** AN Railway, a successor company, 2002– * Aryan Nations, a white supremacist religious organization * Australian National Railways Commission, an Australian rail operator from 1975 until 1987 * Antonov, a Ukrainian (formerly Soviet) aircraft manufacturing and services company, as a model prefix Entertainment and media * Antv, an Indonesian television network * ''Astronomische Nachrichten'', or ''Astronomical Notes'', an international astronomy journal * ''Avisa Nordland'', a Norwegian newspaper * ''Sweet Bean'' (あん), a 2015 Japanese film also known as ''An' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theories Of Cloaking
Theories of cloaking discusses various theories based on science and research, for producing an electromagnetic cloaking device. Theories presented employ transformation optics, event cloaking, dipolar scattering cancellation, tunneling light transmittance, sensors and active sources, and acoustic cloaking. A cloaking device is one where the purpose of the transformation is to hide something, so that a defined region of space is invisibly isolated from passing electromagnetic fields (see Metamaterial cloaking) or sound waves. Objects in the defined location are still present, but incident waves are guided around them without being affected by the object itself. Along with this basic "cloaking device", other related concepts have been proposed in peer reviewed, scientific articles, and are discussed here. Naturally, some of the theories discussed here also employ metamaterials, either electromagnetic or acoustic, although often in a different manner than the original demonstr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamaterials
A metamaterial (from the Greek word μετά ''meta'', meaning "beyond" or "after", and the Latin word ''materia'', meaning "matter" or "material") is any material engineered to have a property that is not found in naturally occurring materials. They are made from assemblies of multiple elements fashioned from composite materials such as metals and plastics. The materials are usually arranged in repeating patterns, at scales that are smaller than the wavelengths of the phenomena they influence. Metamaterials derive their properties not from the properties of the base materials, but from their newly designed structures. Their precise shape, geometry, size, orientation and arrangement gives them their smart properties capable of manipulating electromagnetic waves: by blocking, absorbing, enhancing, or bending waves, to achieve benefits that go beyond what is possible with conventional materials. Appropriately designed metamaterials can affect waves of electromagnetic radiation or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Journal Of Physics
''New Journal of Physics'' is an online-only, open-access, peer-reviewed scientific journal covering research in all aspects of physics, as well as interdisciplinary topics where physics forms the central theme. The journal was established in 1998 and is a joint publication of the Institute of Physics and the Deutsche Physikalische Gesellschaft. It is published by IOP Publishing. The editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The highest-ranking editor of a publication may also be titled editor, managing ... is Andreas Buchleitner ( Albert Ludwigs University). ''New Journal of Physics'' is part of the SCOAP3 initiative. Abstracting and indexing The journal is indexed and abstracted in: References External links * {{Official website, http://iopscience.iop.org/1367-2630 Open access journals Physics journals IOP Publishing academic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transformation Optics
Transformation optics is a branch of optics which applies metamaterials to produce spatial variations, derived from coordinate transformations, which can direct chosen bandwidths of electromagnetic radiation. This can allow for the construction of new composite artificial devices, which probably could not exist without metamaterials and coordinate transformation. Computing power that became available in the late 1990s enables prescribed quantitative values for the permittivity and permeability, the constitutive parameters, which produce localized spatial variations. The aggregate value of all the constitutive parameters produces an effective value, which yields the intended or desired results. Hence, complex artificial materials, known as metamaterials, are used to produce transformations in optical space. The mathematics underpinning transformation optics is similar to the equations that describe how gravity warps space and time, in general relativity. However, instea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Camouflage
Active camouflage or adaptive camouflage is camouflage that adapts, often rapidly, to the surroundings of an object such as an animal or military vehicle. In theory, active camouflage could provide perfect concealment from visual detection. Active camouflage is used in several groups of animals, including reptiles on land, and cephalopod molluscs and flatfish in the sea. Animals achieve active camouflage both by Camouflage#Crypsis by changing skin pattern.2C colour, color change and (among marine animals such as squid) by counter-illumination, with the use of bioluminescence. Military counter-illumination camouflage was first investigated during the World War II, Second World War for marine use. More recent research has aimed to achieve crypsis by using cameras to sense the visible background, and by controlling Peltier panels or coatings that can vary their appearance. In animals Active camouflage is used in several groups of animals including cephalopod molluscs, fish, and r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-fiction
Nonfiction, or non-fiction, is any document or media content that attempts, in good faith, to provide information (and sometimes opinions) grounded only in facts and real life, rather than in imagination. Nonfiction is often associated with being presented more objectively, like historical, scientific, or otherwise straightforward and accurate information, but sometimes, can be presented more subjectively, like sincerely held beliefs and thoughts on a real-world topic. One prominent usage of nonfiction is as one of the two fundamental divisions of narrative (storytelling)—often, specifically, prose writing—in contrast to narrative fiction, which is largely populated by imaginary characters and events, though sometimes ambiguous regarding its basis in reality. Some typical examples of nonfiction include diaries, biographies, news stories, documentary films, textbooks, travel books, recipes, and scientific journals. While specific claims in a nonfiction wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
