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Guy-wire
A guy-wire, guy-line, guy-rope, or stay, also called simply a guy, is a tensioned cable designed to add stability to a free-standing structure. They are used commonly for ship masts, radio masts, wind turbines, utility poles, and tents. A thin vertical mast supported by guy wires is called a guyed mast. Structures that support antennas are frequently of a lattice construction and are called "towers". One end of the guy is attached to the structure, and the other is anchored to the ground at some distance from the mast or tower base. The tension in the diagonal guy-wire, combined with the compression and buckling strength of the structure, allows the structure to withstand lateral loads such as wind or the weight of cantilevered structures. They are installed radially, usually at equal angles about the structure, in trios and quads. As the tower leans a bit due to the wind force, the increased guy tension is resolved into a compression force in the tower or mast and a late ...
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Radio Masts And Towers
Radio masts and towers are typically tall structures designed to support antennas for telecommunications and broadcasting, including television. There are two main types: guyed and self-supporting structures. They are among the tallest human-made structures. Masts are often named after the broadcasting organizations that originally built them or currently use them. In the case of a mast radiator or radiating tower, the whole mast or tower is itself the transmitting antenna. Terminology The terms "mast" and "tower" are often used interchangeably. However, in structural engineering terms, a tower is a self-supporting or cantilevered structure, while a mast is held up by stays or guys. Broadcast engineers in the UK use the same terminology. A mast is a ground-based or rooftop structure that supports antennas at a height where they can satisfactorily send or receive radio waves. Typical masts are of steel lattice or tubular steel construction. Masts themselves play no part in t ...
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Guyed Mast
A guyed mast or guyed tower is a tall thin vertical structure that depends on guy lines (diagonal tensioned cables attached to the ground) for stability. The mast itself has the compressive strength to support its own weight, but does not have the shear strength to stand unsupported. It requires guy lines to stay upright and to resist lateral forces such as wind loads. Guy lines are usually spaced at equal angles about the structure's base. Guyed masts are used for telecommunications, sailing, and meteorology. The tallest guyed mast in the world is currently the KVLY-TV mast near Blanchard, North Dakota, USA. Two subtypes exist. A ''partially guyed tower'' is a structure consisting of a guyed mast on top of a freestanding tower. The guys may be anchored to the top of the freestanding structure, or to the ground. A famous tower of this type is the Gerbrandy Tower. An ''additionally guyed tower'' is a freestanding tower which either has guys attached temporarily to add stab ...
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Sailboat
A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture. Types Although sailboat terminology has varied across history, many terms have specific meanings in the context of modern yachting. A great number of sailboat-types may be distinguished by size, hull configuration, keel type, purpose, number and configuration of masts, and sail plan. Popular monohull designs include: Cutter The cutter is similar to a sloop with a single mast and mainsail, but generally carries the mast further aft to allow for a jib and staysail to be attached to the head stay and inner forestay, respectively. Once a common racing configuration, today it gives versatility to cruising boats, especially in allowing a small staysail to be flown from the inner stay in high winds. Catboat A catboat has a single mast mounted far forward and does not carr ...
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Porcelain
Porcelain () is a ceramic material made by heating substances, generally including materials such as kaolinite, in a kiln to temperatures between . The strength and translucence of porcelain, relative to other types of pottery, arises mainly from vitrification and formation of the mineral mullite within the body at these high temperatures. Though definitions vary, porcelain can be divided into three main categories: hard-paste, soft-paste, and bone china. The category that an object belongs to depends on the composition of the paste used to make the body of the porcelain object and the firing conditions. Porcelain slowly evolved in China and was finally achieved (depending on the definition used) at some point about 2,000 to 1,200 years ago; it slowly spread to other East Asian countries, then to Europe, and eventually to the rest of the world. Its manufacturing process is more demanding than that for earthenware and stoneware, the two other main types of pottery, and it ...
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Radiation Pattern
In the field of antenna design the term radiation pattern (or antenna pattern or far-field pattern) refers to the ''directional'' (angular) dependence of the strength of the radio waves from the antenna or other source.Constantine A. Balanis: “Antenna Theory, Analysis and Design”, John Wiley & Sons, Inc., 2nd ed. 1982 David K Cheng: “Field and Wave Electromagnetics”, Addison-Wesley Publishing Company Inc., Edition 2, 1998. Edward C. Jordan & Keith G. Balmain; “Electromagnetic Waves and Radiating Systems” (2nd ed. 1968) Prentice-Hall. Particularly in the fields of fiber optics, lasers, and integrated optics, the term radiation pattern may also be used as a synonym for the near-field pattern or Fresnel pattern.Institute of Electrical and Electronics Engineers, “The IEEE standard dictionary of electrical and electronics terms”; 6th ed. New York, N.Y., Institute of Electrical and Electronics Engineers, c1997. IEEE Std 100-1996. d. Standards Coordinating Committee 1 ...
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Mast Radiator
Mast, MAST or MASt may refer to: Engineering * Mast (sailing), a vertical spar on a sailing ship * Flagmast, a pole for flying a flag * Guyed mast, a structure supported by guy-wires * Mooring mast, a structure for docking an airship * Radio masts and towers , towers that carry antennas * The primary support for a helicopter rotor * The main vertical structure of a forklift truck * Multi-axis shaker table, an automotive test system * Model for assessment of telemedicine, used to assess long-distance medical treatment Biology * Mast (botany), the edible parts of woody plants * Mast Arboretum, at Stephen F. Austin State University in Nacogdoches, Texas * Mast cell, involved in the allergy response * Mast., in botanical naming, the standard author abbreviation for Maxwell T. Masters * Two microtubule-associated serine/threonine-protein kinase enzymes: ** MAST1, an enzyme that in humans is encoded by the ''MAST1'' gene ** MAST2, an enzyme that in humans is encoded by the ''MAST ...
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KVLY-TV Tower, North Dakota 019
KVLY-TV (channel 11) is a television station in Fargo, North Dakota, United States, affiliated with NBC. It is owned by Gray Television alongside Horace, North Dakota, Horace-licensed low-power broadcasting#Television, low-power dual CBS/The CW Plus, CW+ affiliate KXJB-LD (channel 30). Both stations share studios on 21st Avenue South in Fargo, while KVLY-TV's KVLY-TV mast, transmitter is located near Blanchard, North Dakota, Blanchard. In addition to its main studio in Fargo, KVLY-TV operates a news bureau and sales office in the U.S. Bancorp, US Bank building in downtown Grand Forks, North Dakota, Grand Forks. KVLY-TV is considered a part of the NBC North Dakota state network of NBC affiliates, although it airs separate newscasts and syndicated programming from flagship (broadcasting), flagship and sister station KFYR-TV in Bismarck, North Dakota, Bismarck. KVLY-TV is most notable for its KVLY-TV mast, broadcast tower, which was the fourth tallest above-ground structure in th ...
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Sidewalk Guy Wire
A sidewalk (North American English), pavement (British English), footpath in Australia, India, New Zealand and Ireland, or footway, is a path along the side of a street, highway, terminals. Usually constructed of concrete, pavers, brick, stone, or asphalt, it is designed for pedestrians. A sidewalk is normally higher than the roadway, and separated from it by a kerb (spelled "curb" in North America). There may also be a planted strip between the sidewalk and the roadway and between the roadway and the adjacent land. In some places, the same term may also be used for a paved path, trail or footpath that is not next to a road, for example, a path through a park. Terminology The term "sidewalk" is preferred in most of North America. The term "pavement" is more common in the United Kingdom and other members of the Commonwealth of Nations, as well as parts of the Mid-Atlantic United States such as Philadelphia and parts of New Jersey. Many Commonwealth countries use the term "fo ...
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Strain Insulator
A strain insulator is an electrical insulator that is designed to work in mechanical tension (strain), to withstand the pull of a suspended electrical wire or cable. They are used in overhead electrical wiring, to support radio antennas and overhead power lines. A strain insulator may be inserted between two lengths of wire to isolate them electrically from each other while maintaining a mechanical connection, or where a wire attaches to a pole or tower, to transmit the pull of the wire to the support while insulating it electrically. Strain insulators were first used in telegraph systems in the mid 19th century. Description and use A typical strain insulator is a piece of glass, porcelain, or fiberglass that is shaped to accommodate two cables or a cable shoe and the supporting hardware on the support structure (hook eye, or eyelet on a steel pole/tower). The shape of the insulator maximizes the distance between the cables while also maximizing the load-bearing transfer capac ...
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Utility Pole
A utility pole is a column or post typically made out of wood used to support overhead power lines and various other public utilities, such as electrical cable, optical fiber, fiber optic cable, and related equipment such as Distribution transformer, transformers and street lights. It can be referred to as a transmission pole, telephone pole, telecommunication pole, power pole, hydro pole, telegraph pole, or telegraph post, depending on its application. A Stobie pole is a multi-purpose pole made of two steel joists held apart by a slab of concrete in the middle, generally found in South Australia. Electrical wires and cables are routed overhead on utility poles as an inexpensive way to keep them insulated from the ground and out of the way of people and vehicles. Utility poles can be made of wood, metal, concrete, or composites like fiberglass. They are used for two different types of power lines: ''sub transmission lines'', which carry higher voltage power between substations, ...
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Spinnaker Pole
A spinnaker pole is a spar used in sailboats (both dinghys and yachts) to help support and control a variety of headsails, particularly the spinnaker. However, it is also used with other sails, such as genoas and jibs, when sailing downwind with no spinnaker hoisted. (Since the load on a spinnaker pole is very light on this point of sailing, sometimes a special light spinnaker pole called a whisker pole is used in these circumstances.) The spinnaker pole is rigged to run from the base of the mast, where there is a special fitting for attaching one end of the pole, out to windward over the side of the boat. There, one of the control lines of whichever sail it is to be used with is run through a fitting on the other end of the spinnaker pole. This allows for more precise control of the corner of the sail to which the line is attached. For a spinnaker, the line attached to the pole is the guy, or brace, and the corner is the tack. For other headsails, such as a jib, the line would ...
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