Long-range Acoustic Device
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Long-range Acoustic Device
A long-range acoustic device (LRAD) is an acoustic hailing device (AHD), sound cannon and sonic weapon developed by Genasys. It has been used as a method of crowd control, which has caused permanent hearing damage, having an extremely high decibel capacity (up to 160 dB measured at one meter from the device). Other uses have included for negotiations in siege situations to deal with piracy at sea; for mass notification during natural disasters or other emergencies; and by defense forces, including several navies. History In October 2000 the , an American guided missile destroyer, was bombed in a terrorist attack by al-Qaeda operatives, using a small boat packed with explosives. The naval personnel on Cole were unable to be sure that their messages could be heard by the approaching boat at a sufficient distance to possibly avert the attack. The ship was badly damaged, 17 U.S. Navy sailors killed and 37 injured. Following this attack, navies around the world made severa ...
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American Institute Of Physics
The American Institute of Physics (AIP) promotes science and the profession of physics, publishes physics journals, and produces publications for scientific and engineering societies. The AIP is made up of various member societies. Its corporate headquarters are at the American Center for Physics in College Park, Maryland, but the institute also has offices in Melville, New York, and Beijing. Historical overview The AIP was founded in 1931 as a response to lack of funding for the sciences during the Great Depression. /www.aip.org/aip/history "History of AIP" American Institute of Physics. July 2010. It formally incorporated in 1932 consisting of five original "member societies", and a total of four thousand members. A new set of member societies was added beginning in the mid-1960s. As soon as the AIP was established it began publishing scientific journals.
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Emergency Management
Emergency management or disaster management is the managerial function charged with creating the framework within which communities reduce vulnerability to hazards and cope with disasters. Emergency management, despite its name, does not actually focus on the management of emergencies, which can be understood as minor events with limited impacts and are managed through the day to day functions of a community. Instead, emergency management focuses on the management of disasters, which are events that produce more impacts than a community can handle on its own. The management of disasters tends to require some combination of activity from individuals and households, organizations, local, and/or higher levels of government. Although many different terminologies exist globally, the activities of emergency management can be generally categorized into preparedness, response, mitigation, and recovery, although other terms such as disaster risk reduction and prevention are also common. Th ...
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Critical Infrastructure
Critical infrastructure (or critical national infrastructure (CNI) in the UK) is a term used by governments to describe assets that are essential for the functioning of a society and economy – the infrastructure. Most commonly associated with the term are facilities for: * Shelter; Heating (e.g. natural gas, fuel oil, district heating); * Agriculture, food production and distribution; * Education, skills development and technology transfer / basic subsistence and unemployment rate statistics; * Water supply (drinking water, waste water/sewage, stemming of surface water (e.g. dikes and sluices)); * Public health (hospitals, ambulances); * Transportation systems (fuel supply, railway network, airports, harbours, inland shipping); * Security services (police, military). * Electricity generation, transmission and distribution; (e.g. natural gas, fuel oil, coal, nuclear power) ** Renewable energy, which are naturally replenished on a human timescale, such as sunlight, wind, rain, ...
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Border Security
Border control refers to measures taken by governments to monitor and regulate the movement of people, animals, and goods across land, air, and maritime borders. While border control is typically associated with international borders, it also encompasses controls imposed on internal borders within a single state. Border control measures serve a variety of purposes, ranging from enforcing customs, sanitary and phytosanitary, or biosecurity regulations to restricting migration. While some borders (including most states' internal borders and international borders within the Schengen Area) are open and completely unguarded, others (including the vast majority of borders between countries as well as some internal borders) are subject to some degree of control and may be crossed legally only at designated checkpoints. Border controls in the 21st century are tightly intertwined with intricate systems of travel documents, visas, and increasingly complex policies that vary between ...
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Fire And Rescue
A fire department (American English) or fire brigade (Commonwealth English), also known as a fire authority, fire district, fire and rescue, or fire service in some areas, is an organization that provides fire prevention and fire suppression services. Fire departments are most commonly a public sector organization that operate within a municipality, county, state, nation, or special district. Private and specialist firefighting organizations also exist, such as those for aircraft rescue and firefighting. A fire department contains one or more fire stations within its boundaries, and may be staffed by firefighters, who may be professional, volunteers, conscripts, or on-call. Combination fire departments employ a mix of professional and volunteer firefighters. Organization Fire departments are organized in a system of administration, services, training, and operations; for example: * Administration is responsible for supervision, budgets, policy, and human resources. * Servic ...
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Naval Base
A naval base, navy base, or military port is a military base, where warships and naval ships are docked when they have no mission at sea or need to restock. Ships may also undergo repairs. Some naval bases are temporary homes to aircraft that usually stay on ships but are undergoing maintenance while the ship is in port. In the United States, the United States Department of the Navy's General Order No. 135 issued in 1911 as a formal guide to naval terminology described a naval station as "any establishment for building, manufacturing, docking, repair, supply, or training under control of the Navy. It may also include several establishments". A naval base, by contrast, was "a point from which naval operations may be conducted". In most countries, naval bases are expressly named and identified as such. One peculiarity of the Royal Navy and certain other navies which closely follow British naval traditions is the concept of the stone frigate A stone frigate is a naval esta ...
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Coast Guard
A coast guard or coastguard is a maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with customs and security duties to being a volunteer organization tasked with search and rescue without law enforcement authority. In most countries, a typical coast guard's functions are distinct from those of the navy (a military service) and the transit police (a law enforcement agency), while in certain countries has similarities to both. History The predecessor of the United Kingdom's modern His Majesty's Coastguard was established in 1809 as the Waterguard, a department of the HM Customs and Excise authority, which was originally devoted to the prevention of smuggling. At the time, due to high UK taxation on liquors such as brandy, and on tobacco etc., smuggling of such cargoes from places such as France, Belgium, and Holland was an attractive proposition for many; ...
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Gunshot
A gunshot is a single discharge of a gun, typically a man-portable firearm, producing a visible flash, a powerful and loud shockwave and often chemical gunshot residue. The term can also refer to a ballistic wound caused by such a discharge. Multiple discharges of one or more firearms are referred to as gunfire. The word can connote either the sound of a gun firing, the projectiles that were fired, or both. For example, the statement "gunfire came from the next street" could either mean the sound of discharge, or it could mean the bullets that were discharged. It is better to be a bit more specific while writing however. "The sound of gunfire" or "we came under gunfire" would be more descriptive and prevent confusion. In the latter phrase, in particular, "fire" is used more (i.e. "under fire"), as both words hold the same general meaning within the proper context. Gunfire characteristics There are three primary attributes that characterize gunfire and hence enable the ...
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Jet Engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term typically refers to an internal combustion airbreathing jet engine such as a turbojet, turbofan, ramjet, or pulse jet engine, pulse jet. In general, jet engines are internal combustion engines. Airbreathing jet engines typically feature a Axial compressor, rotating air compressor powered by a turbine, with the leftover power providing thrust through the propelling nozzle—this process is known as the Brayton cycle, Brayton thermodynamic cycle. Jet aircraft use such engines for long-distance travel. Early jet aircraft used turbojet engines that were relatively inefficient for subsonic flight. Most modern subsonic jet aircraft use more complex High-bypass turbofan, high-bypass turbofan engines. They give higher speed and greater fuel eff ...
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John Wiley And Sons
John Wiley & Sons, Inc., commonly known as Wiley (), is an American multinational publishing company founded in 1807 that focuses on academic publishing and instructional materials. The company produces books, journals, and encyclopedias, in print and electronically, as well as online products and services, training materials, and educational materials for undergraduate, graduate, and continuing education students. History The company was established in 1807 when Charles Wiley opened a print shop in Manhattan. The company was the publisher of 19th century American literary figures like James Fenimore Cooper, Washington Irving, Herman Melville, and Edgar Allan Poe, as well as of legal, religious, and other non-fiction titles. The firm took its current name in 1865. Wiley later shifted its focus to scientific, technical, and engineering subject areas, abandoning its literary interests. Wiley's son John (born in Flatbush, New York, October 4, 1808; died in East Orange, New Jer ...
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Near And Far Field
The near field and far field are regions of the electromagnetic (EM) field around an object, such as a transmitting antenna, or the result of radiation scattering off an object. Non-radiative ''near-field'' behaviors dominate close to the antenna or scattering object, while electromagnetic radiation ''far-field'' behaviors dominate at greater distances. Far-field E (electric) and B (magnetic) field strength decreases as the distance from the source increases, resulting in an inverse-square law for the radiated ''power'' intensity of electromagnetic radiation. By contrast, near-field E and B strength decrease more rapidly with distance: the radiative field decreases by the inverse-distance squared, the reactive field by an inverse-cube law, resulting in a diminished power in the parts of the electric field by an inverse fourth-power and sixth-power, respectively. The rapid drop in power contained in the near-field ensures that effects due to the near-field essentially vanish a ...
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