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USS Defender (MCM-2)
USS ''Defender'' (MCM-2) was an mine countermeasures ship in the service of the United States Navy. She entered service in September 1989 and was decommissioned in October 2014. History It was laid down on 1 December 1983 at Marinette Marine Corp., Marinette, Wisconsin; launched on 4 April 1987; and commissioned on 30 September 1989. As of 1 July 2009, she was active in Mine Countermeasures Squadron Seven, U.S. Pacific Fleet, permanently forward deployed to Sasebo, Japan. ''Defender'' was decommissioned at San Diego on 1 October 2014. As of 2019, she is in reserve as a part of the Pacific Reserve Fleet. Systems Auxiliary systems: three Waukesha ship service diesel generator sets, one solar gas turbine generator, one omnithruster bow thruster system. Electronic systems: one AN/SSN-2 Precise Integrated Navigation System (PINS), one AN/SQQ-32 Mine Hunting Sonar, one AN/SPS-55 Surface Radar, one AN/WSN-7 Gyro compass, Mine Countermeasure Equipment Suite, one AN/SLQ-48 ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pearl Harbor
Pearl Harbor is an American lagoon harbor on the island of Oahu, Hawaii, west of Honolulu. It was often visited by the Naval fleet of the United States, before it was acquired from the Hawaiian Kingdom by the U.S. with the signing of the Reciprocity Treaty of 1875. Much of the harbor and surrounding lands are now a United States Navy deep-water naval base. It is also the headquarters of the United States Pacific Fleet. The U.S. government first obtained exclusive use of the inlet and the right to maintain a repair and coaling station for ships here in 1887. The surprise attack by the Imperial Japanese Navy on December 7, 1941, led the United States to declare war on the Empire of Japan, making the attack on Pearl Harbor the immediate cause of the United States' entry into World War II. History Pearl Harbor was originally an extensive shallow embayment called ''Wai Momi'' (meaning, “Waters of Pearl”) or ''Puuloa'' (meaning, “long hill”) by the Hawaiians. Puuloa was r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Power
Solar power is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power. Photovoltaic cells convert light into an electric current using the photovoltaic effect. Concentrated solar power systems use lenses or mirrors and solar tracking systems to focus a large area of sunlight to a hot spot, often to drive a steam turbine. Photovoltaics were initially solely used as a source of electricity for small and medium-sized applications, from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system. Commercial concentrated solar power plants were first developed in the 1980s. Since then, as the cost of solar electricity has fallen, grid-connected solar PV systems have grown more or less exponentially. Millions of installations and gigawatt-scale photovoltaic power stations continue to be built, with half of new generation capacity being solar in 2021. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minesweeper (ship)
A minesweeper is a small warship designed to remove or detonate naval mines. Using various mechanisms intended to counter the threat posed by naval mines, minesweepers keep waterways clear for safe shipping. History The earliest known usage of the naval mine dates to the Ming dynasty.Needham, Volume 5, Part 7, 203–205. Dedicated minesweepers, however, only appeared many centuries later during the Crimean War, where they were deployed by the British. The Crimean War minesweepers were rowboats trailing grapnels to snag mines. Minesweeping technology picked up in the Russo-Japanese War, using aging torpedo boats as minesweepers. In Britain, naval leaders recognized before the outbreak of World War I that the development of sea mines was a threat to the nation's shipping and began efforts to counter the threat. Sir Arthur Wilson noted the real threat of the time was blockade aided by mines and not invasion. The function of the fishing fleet's trawlers with their trawl gear was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustic Signature
The term acoustic signature is used to describe a combination of acoustic emissions of sound emitters, such as those of ships and submarines. In addition, aircraft, machinery, and living animals can be described as having their own characteristic acoustic signatures or sound attributes, which can be used to study their condition, behavior, and physical location. Military use The analysis of acoustic signatures is an important adjunct to passive sonar used to track naval warships and weapons. Similar methods have been used to identify aircraft, especially before the development of sophisticated radar tracking. Sound characteristics The acoustic signature is made up of a number of individual elements. These include: *Machinery noise: noise generated by a ship's engines, propeller shafts, fuel pumps, air conditioning systems, etc. *Cavitation noise: noise generated by the creation of gas bubbles by the turning of a ship's propellers. *Hydrodynamic noise: noise generated by the m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particles give rise to a magnetic field, which acts on other currents and magnetic moments. Magnetism is one aspect of the combined phenomena of electromagnetism. The most familiar effects occur in ferromagnetic materials, which are strongly attracted by magnetic fields and can be magnetized to become permanent magnets, producing magnetic fields themselves. Demagnetizing a magnet is also possible. Only a few substances are ferromagnetic; the most common ones are iron, cobalt, and nickel and their alloys. The rare-earth metals neodymium and samarium are less common examples. The prefix ' refers to iron because permanent magnetism was first observed in lodestone, a form of natural iron ore called magnetite, Fe3O4. All substances exhibit some type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutralization (immunology)
A neutralizing antibody (NAb) is an antibody that defends a cell from a pathogen or infectious particle by neutralizing any effect it has biologically. Neutralization renders the particle no longer infectious or pathogenic. Neutralizing antibodies are part of the humoral response of the adaptive immune system against viruses, intracellular bacteria and microbial toxin. By binding specifically to surface structures (antigen) on an infectious particle, neutralizing antibodies prevent the particle from interacting with its host cells it might infect and destroy. Mechanism In order to enter cells, pathogens, such as circulating viral particles or extracellular bacteria, use molecules on their surfaces to interact with the cell surface receptors of their target cell which allows them to enter the cell and start their replication cycle. Neutralizing antibodies can inhibit infectivity by binding to the pathogen and blocking the molecules needed for cell entry. This can be due to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Countermeasure
A countermeasure is a measure or action taken to counter or offset another one. As a general concept, it implies precision and is any technological or tactical solution or system designed to prevent an undesirable outcome in the process. The first known use of the term was in 1923. "Countermeasure" defined Countermeasures can refer to the following disciplinary spectrum: * Medicine * Materials engineering * Electro-magnetic engineering * Policing * Information technology * * Diplomatic security * Pollution prevention * Aviation Defense countermeasures are often divided into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gyro Compass
A gyrocompass is a type of non-magnetic compass which is based on a fast-spinning disc and the rotation of the Earth (or another planetary body if used elsewhere in the universe) to find geographical direction automatically. The use of a gyrocompass is one of the seven fundamental ways to determine the heading of a vehicle. A gyroscope is an essential component of a gyrocompass, but they are different devices; a gyrocompass is built to use the effect of gyroscopic precession, which is a distinctive aspect of the general gyroscopic effect. Gyrocompasses are widely used for navigation on ships, because they have two significant advantages over magnetic compasses: * they find true north as determined by the axis of the Earth's rotation, which is different from, and navigationally more useful than, ''magnetic'' north, and * they are unaffected by ferromagnetic materials, such as in a ship's steel hull, which distort the magnetic field. Aircraft commonly use gyroscopic instrumen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radar
Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. Radio waves (pulsed or continuous) from the transmitter reflect off the objects and return to the receiver, giving information about the objects' locations and speeds. Radar was developed secretly for military use by several countries in the period before and during World War II. A key development was the cavity magnetron in the United Kingdom, which allowed the creation of relatively small systems with sub-meter resolution. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigation, navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels. "Sonar" can refer to one of two types of technology: ''passive'' sonar means listening for the sound made by vessels; ''active'' sonar means emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation, and SODAR (an upward-looking in-air sonar) is used for atmospheric investigations. The term ''sonar'' is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low (infrasonic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navigation
Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.Bowditch, 2003:799. The field of navigation includes four general categories: land navigation, marine navigation, aeronautic navigation, and space navigation. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks. All navigational techniques involve locating the navigator's position compared to known locations or patterns. Navigation, in a broader sense, can refer to any skill or study that involves the determination of position and direction. In this sense, navigation includes orienteering and pedestrian navigation. History In the European medieval period, navigation was considered part of the set of '' seven mechanical arts'', none of which were used for long voyages across open ocean. Polynesian navigation is probably the earliest form of open-ocean navigation; it was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic System
Electronic may refer to: *Electronics, the science of how to control electric energy in semiconductor * ''Electronics'' (magazine), a defunct American trade journal *Electronic storage, the storage of data using an electronic device *Electronic commerce or e-commerce, the trading in products or services using computer networks, such as the Internet *Electronic publishing or e-publishing, the digital publication of books and magazines using computer networks, such as the Internet *Electronic engineering, an electrical engineering discipline Entertainment *Electronic (band), an English alternative dance band ** ''Electronic'' (album), the self-titled debut album by British band Electronic *Electronic music, a music genre *Electronic musical instrument *Electronic game, a game that employs electronics See also *Electronica, an electronic music genre *Consumer electronics Consumer electronics or home electronics are electronic (analog or digital) equipment intended for everyday ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
