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Wind Tetrahedron
A windsock (also called a wind cone) is a conical textile tube that resembles a giant sock. It can be used as a basic indicator of wind speed and direction, or as decoration. They are typically used at airports to show the direction and strength of the wind to pilots, and at chemical plants where there is risk of gaseous leakage. They are also sometimes located alongside highways at windy locations. At many airports, windsocks are externally or internally lit at night. Function Wind direction is the direction in which the windsock is pointing. (Wind directions are conventionally specified as the compass point from which the wind originates; so a windsock pointing due north indicates a southerly wind). Wind speed is indicated by the windsock's angle relative to the mounting pole; in low winds it droops; in high winds it flies horizontally. Alternating stripes of high visibility orange and white were initially used to help to estimate wind speed, with each stripe addi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemometer
In meteorology, an anemometer () is a device that measures wind speed and direction. It is a common instrument used in weather stations. The earliest known description of an anemometer was by Italian architect and author Leon Battista Alberti (1404–1472) in 1450. History The anemometer has changed little since its development in the 15th century. Alberti is said to have invented it around 1450. In the ensuing centuries numerous others, including Robert Hooke (1635–1703), developed their own versions, with some mistakenly credited as its inventor. In 1846, John Thomas Romney Robinson (1792–1882) improved the design by using four hemispherical cups and mechanical wheels. In 1926, Canadian meteorologist John Patterson (1872–1956) developed a three-cup anemometer, which was improved by Brevoort and Joiner in 1935. In 1991, Derek Weston added the ability to measure wind direction. In 1994, Andreas Pflitsch developed the sonic anemometer. Velocity anemometers Cup anemomet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angle
In Euclidean geometry, an angle is the figure formed by two Ray (geometry), rays, called the ''Side (plane geometry), sides'' of the angle, sharing a common endpoint, called the ''vertex (geometry), vertex'' of the angle. Angles formed by two rays lie in the plane (geometry), plane that contains the rays. Angles are also formed by the intersection of two planes. These are called dihedral angles. Two intersecting curves may also define an angle, which is the angle of the rays lying tangent to the respective curves at their point of intersection. ''Angle'' is also used to designate the measurement, measure of an angle or of a Rotation (mathematics), rotation. This measure is the ratio of the length of a arc (geometry), circular arc to its radius. In the case of a geometric angle, the arc is centered at the vertex and delimited by the sides. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any other point and its image by the rotation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airport Infrastructure
An airport is an aerodrome with extended facilities, mostly for commercial air transport. Airports usually consists of a landing area, which comprises an aerially accessible open space including at least one operationally active surface such as a runway for a airplane, plane to take off and to land or a helipad, and often includes adjacent utility buildings such as control towers, hangars and airport terminal, terminals, to maintain and monitor aircraft. Larger airports may have airport aprons, taxiway bridges, air traffic control centres, passenger facilities such as restaurants and Airport lounge, lounges, and emergency services. In some countries, the US in particular, airports also typically have one or more fixed-base operators, serving general aviation. Operating airports is extremely complicated, with a complex system of aircraft support services, passenger services, and aircraft control services contained within the operation. Thus airports can be major employers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koinobori
, meaning "carp streamer" in Japanese, are carp-shaped windsocks traditionally flown in Japan to celebrate , a traditional calendrical event which is now designated as , a national holiday in Japan. are made by drawing carp patterns on paper, cloth or other nonwoven fabric. They are then allowed to flutter in the wind. They are also known as . Children's Day takes place on May 5, the last day of Golden Week, the largest break for workers and also a week in which many businesses, state schools, and some private schools close for up to 9–10 days for the designated national holidays. Landscapes across Japan are decorated with from April to early May, in honor of children for a good future and in the hope that they will grow up healthy and strong. The is included in Unicode as . Description A typical set consists of, from the top of the pole down, a pair of with a ball-shaped spinning vane, a mounting , and finally the . For the windsock above the , two main kinds are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roman Cavalry
Roman cavalry (Latin: ''equites Romani'') refers to the horse-mounted forces of the Roman army throughout the Regal, Republican, and Imperial eras. In the Regal era the Roman cavalry was a group of 300 soldiers called '' celeres'', tasked with guarding the king. Later their numbers were doubled to 600, then possibly 1,800. All of the cavalrymen were patricians. In the Republican era, the general name for the cavalry was Equites and consisted of the Equites class and the First Class, with a group of 300 cavalrymen in every legion. They were divided into 10 groups of 30 men. Each group elected three leaders known as ''decuriones''. Later the Roman cavalry stopped using Roman citizens as cavalrymen and relied on Auxilia and foreign recruits. Roman cavalrymen wore a Corinthian helmet, bronze chestplate, and bronze greaves. Later mail was adopted into the army. Their arms included a lance ('' lanceae''), a long sword (''spatha''), and short throwing spears (''akontes''). Hist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Military Standard
In military organizations, the practice of carrying colours (or colors), standards, flags, or guidons, both to act as a rallying point for troops and to mark the location of the commander, is thought to have originated in Ancient Egypt some 5,000 years ago. The Roman Empire also made battle standards a part of their vast armies. It was formalized in the armies of Europe in the High Middle Ages, with standards being emblazoned with the commander's coat of arms. General use As armies became trained and adopted set formations, each regiment's ability to keep its formation was potentially critical to its, and therefore its army's, success. In the chaos of battle, not least due to the amount of dust and smoke on a battlefield, soldiers needed to be able to determine where their regiment was. Regimental flags are generally awarded to a regiment by a head of state during a ceremony. They were therefore treated with reverence as they represented the honour and traditions of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Draco (military Standard)
The ("dragon" or "serpent", plural ) was a military standard of the Roman cavalry. Carried by the , the was the standard of the cohort, as the eagle () was that of the legion. The may have been introduced to the Roman army after the Dacian wars by Dacian, Sarmatian units in the 2nd century. According to Vegetius, in the 4th century a was carried by each legionary cohort. Literary descriptions The Greek military writer Arrian describes the in his passage on cavalry training exercises, calling it "Scythian": The Scythian banners are ''dracontes'' held aloft on standard-length poles. They are made of colored cloths stitched together, and from the head along the entire body to the tail, they look like snakes. When the horses bearing these devices are not in motion, you see only variegated streamers hanging down. During the charge is when they most resemble creatures: they are inflated by the wind, and even make a sort of hissing sound as the air is forced through them. Arr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Sock
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth's surface, absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation). By mole fraction (i.e., by number of molecules), dry air contains 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere. Air composition, temperature, and atmospheric pressure vary with altitude. Within the atmosphere, air suitable for use in photosynthesis by terrestrial plants and breathing of terrestrial animals is found only in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICAO
The International Civil Aviation Organization (ICAO, ) is a specialized agency of the United Nations that coordinates the principles and techniques of international air navigation, and fosters the planning and development of international air transport to ensure safe and orderly growth. ICAO headquarters are located in the '' Quartier International'' of Montreal, Quebec, Canada. The ICAO Council adopts standards and recommended practices concerning air navigation, its infrastructure, flight inspection, prevention of unlawful interference, and facilitation of border-crossing procedures for international civil aviation. ICAO defines the protocols for air accident investigation that are followed by transport safety authorities in countries signatory to the Chicago Convention on International Civil Aviation. The Air Navigation Commission (ANC) is the technical body within ICAO. The commission is composed of 19 commissioners, nominated by the ICAO's contracting states and appo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transport Canada
Transport Canada (french: Transports Canada) is the department within the Government of Canada responsible for developing regulations, policies and services of road, rail, marine and air transportation in Canada. It is part of the Transportation, Infrastructure and Communities (TIC) portfolio. The current Minister of Transport is Omar Alghabra. Transport Canada is headquartered in Ottawa, Ontario. History The Department of Transport was created in 1935 by the government of William Lyon Mackenzie King in recognition of the changing transportation environment in Canada at the time. It merged three departments: the former Department of Railways and Canals, the Department of Marine, and the Civil Aviation Branch of the Department of National Defence (c. 1927 when it replaced the Air Board) under C. D. Howe, who would use the portfolio to rationalize the governance and provision of all forms of transportation (air, water and land). He created a National Harbours Board and Trans-C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Aviation Administration
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic management, certification of personnel and aircraft, setting standards for airports, and protection of U.S. assets during the launch or re-entry of commercial space vehicles. Powers over neighboring international waters were delegated to the FAA by authority of the International Civil Aviation Organization. Created in , the FAA replaced the former Civil Aeronautics Administration (CAA) and later became an agency within the U.S. Department of Transportation. Major functions The FAA's roles include: *Regulating U.S. commercial space transportation *Regulating air navigation facilities' geometric and flight inspection standards *Encouraging and developing civil aeronautics, including new aviation technology *Issuing, suspending, or revoking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knot (unit)
The knot () is a unit of speed equal to one nautical mile per hour, exactly (approximately or ). The ISO standard symbol for the knot is kn. The same symbol is preferred by the Institute of Electrical and Electronics Engineers (IEEE), while kt is also common, especially in aviation, where it is the form recommended by the International Civil Aviation Organization (ICAO). The knot is a non- SI unit. The knot is used in meteorology, and in maritime and air navigation. A vessel travelling at 1 knot along a meridian travels approximately one minute of geographic latitude in one hour. Definitions ;1 international knot = :1 nautical mile per hour (by definition), : (exactly), : (approximately), : (approximately), : (approximately) : (approximately). The length of the internationally agreed nautical mile is . The US adopted the international definition in 1954, having previously used the US nautical mile (). The UK adopted the international nautical mile definition in 1970, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
