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Raytheon Company
The Raytheon Company was a major U.S. defense contractor and industrial corporation with manufacturing concentrations in weapons and military and commercial electronics. It was previously involved in corporate and special-mission aircraft until early 2007. Raytheon was the world's largest producer of guided missiles. In April 2020, the company merged with United Technologies Corporation to form Raytheon Technologies. Established in 1922, the company reincorporated in 1928 and adopted its present name in 1959. During 2018, the company had around 67,000 employees worldwide and annual revenues of approximately US$25.35 billion. More than 90% of Raytheon's revenues were obtained from military contracts and, as of 2012, it was the fifth-largest military contractor in the world. , it was the third largest defense contractor in the United States by defense revenue. In 2003, Raytheon's headquarters moved from Lexington, Massachusetts, to Waltham, Massachusetts. The company had previ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voltage-regulator Tube
A voltage-regulator tube (VR tube) is an electronic component used as a shunt regulator to hold a voltage constant at a pre-determined level. Physically, these devices resemble vacuum tubes, but there are two main differences: * Their glass envelopes are filled with a gas mixture, and * They have a cold cathode; the cathode is not heated with a filament to emit electrons. Electrically, these devices resemble Zener diodes, with the following major differences: * They rely on gas ionization, rather than Zener breakdown * The unregulated supply voltage must be 15–20% above the nominal output voltage to ensure that the discharge starts * The output can be higher than nominal if the current through the tube is too low. When sufficient voltage is applied across the electrodes, the gas ionizes, forming a glow discharge around the cathode electrode. The VR tube then acts as a negative resistance device; as the current through the device increases, the amount of ionization also increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United Technologies
United Technologies Corporation (UTC) was an American multinational conglomerate headquartered in Farmington, Connecticut. It researched, developed, and manufactured products in numerous areas, including aircraft engines, aerospace systems, HVAC, elevators and escalators, fire and security, building automation, and industrial products, among others. UTC was also a large military contractor, getting about 10% of its revenue from the U.S. government. Gregory J. Hayes was the CEO and chairman. In April 2020 UTC merged with the Raytheon Company to form Raytheon Technologies. History Pre-1970s 1970s and 1980s In 1974, Harry Gray left Litton Industries to become the CEO of United Aircraft.. He pursued a strategy of growth and diversification, changing the parent corporation's name to United Technologies Corporation (UTC) in 1975 to reflect the intent to diversify into numerous high tech fields beyond aerospace.. (The change became official on May 1, 1975.) The diversificati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guided Missile
In military terminology, a missile is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously unguided rocket is made guided). Missiles have five system components: targeting, guidance system, flight system, engine and warhead. Missiles come in types adapted for different purposes: surface-to-surface and air-to-surface missiles (ballistic, cruise, anti-ship, anti-submarine, anti-tank, etc.), surface-to-air missiles (and anti-ballistic), air-to-air missiles, and anti-satellite weapons. Airborne explosive devices without propulsion are referred to as shells if fired by an artillery piece and bombs if dropped by an aircraft. Unguided jet- or rocket-propelled weapons are usually described as rocket artillery. Historically, the word ''missile'' referred to any projectile that is thrown, shot or propelled towards a target; this usage is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest include planets, natural satellite, moons, stars, nebulae, galaxy, galaxies, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond atmosphere of Earth, Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Babylonian astronomy, Babylonians, Greek astronomy, Greeks, Indian astronomy, Indians, Egyptian astronomy, Egyptians, Chinese astronomy, Chinese, Maya civilization, Maya, and many anc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helium
Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table. Its boiling and melting point are the lowest among all the elements. It is the second lightest and second most abundant element in the observable universe (hydrogen is the lightest and most abundant). It is present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this in both the Sun and in Jupiter, due to the very high nuclear binding energy (per nucleon) of helium-4, with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. The most common isotope of helium in the universe is helium-4, the vast majority of which was formed during t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refrigeration
The term refrigeration refers to the process of removing heat from an enclosed space or substance for the purpose of lowering the temperature.International Dictionary of Refrigeration, http://dictionary.iifiir.org/search.phpASHRAE Terminology, https://www.ashrae.org/technical-resources/free-resources/ashrae-terminology Refrigeration can be considered an artificial, or human-made, cooling method. Refrigeration refers to the process by which energy, in the form of heat, is removed from a low-temperature medium and transferred to a high-temperature medium. This work of energy transfer is traditionally driven by mechanical means, but can also be driven by heat, magnetism, electricity, laser, or other means. Refrigeration has many applications, including household refrigerators, industrial freezers, cryogenics, and air conditioning. Heat pumps may use the heat output of the refrigeration process, and also may be designed to be reversible, but are otherwise similar to air conditioning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tufts University School Of Engineering
The School of Engineering is one of the ten schools that comprise Tufts University. The school offers undergraduate and graduate degrees in several engineering disciplines and computer science fields. Along with the School of Arts and Sciences (A&S) and the Fletcher School of Law and Diplomacy, the School of Engineering is located on the university's main campus in Medford and Somerville, Massachusetts. Currently, the engineering school enrolls more than 800 full-time undergraduates and 600 graduate students. The school employs over 100 full-time and part-time faculty members. History Engineering instruction began at Tufts College in academic year 1865 - 1866, with the introduction of a three-year degree program in civil engineering. Students in this program received the degree of civil engineer. In 1890, the Department of Electrical Engineering was created, and in academic year 1892-1893, the course of study was extended to four years. With the advent of the four-year program ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tomahawk Block IV Cruise Missile
The Tomahawk () Land Attack Missile (TLAM) is a long-range, all-weather, jet-powered, subsonic cruise missile that is primarily used by the United States Navy and Royal Navy in ship and submarine-based land-attack operations. Under contract from the U.S. Navy, the Tomahawk was designed at the APL/ JHU in a project led by James Walker near Laurel, Maryland, and was first manufactured by General Dynamics in the 1970s. It was intended to fill the role of a medium- to long-range, low-altitude missile that could be launched from a naval surface warfare platform, and featured a modular design accommodating a wide variety of warhead, guidance, and range capabilities. At least six variants and multiple upgraded versions of the TLAM have been added since the original design was introduced, including air-, sub-, and ground-launched variants with conventional and nuclear armaments. In 1992–1994, McDonnell Douglas Corporation was the sole supplier of Tomahawk Missiles and produced Bloc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newton, Massachusetts
Newton is a city in Middlesex County, Massachusetts, United States. It is approximately west of downtown Boston. Newton resembles a patchwork of thirteen villages, without a city center. According to the 2020 U.S. Census, the population of Newton was 88,923. History Newton was settled in 1630 as part of "the newe towne", which was renamed Cambridge in 1638. Roxbury minister John Eliot persuaded the Native American people of Nonantum, a sub-tribe of the Massachusett led by a sachem named Waban, to relocate to Natick in 1651, fearing that they would be exploited by colonists. Newton was incorporated as a separate town, known as Cambridge Village, on December 15, 1681, then renamed Newtown in 1691, and finally Newton in 1766. It became a city on January 5, 1874. Newton is known as ''The Garden City''. In ''Reflections in Bullough's Pond'', Newton historian Diana Muir describes the early industries that developed in the late 18th and early 19th centuries in a series of mills b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lexington, Massachusetts
Lexington is a suburban town in Middlesex County, Massachusetts, United States. It is 10 miles (16 km) from Downtown Boston. The population was 34,454 as of the 2020 census. The area was originally inhabited by Native Americans, and was first settled by Europeans in 1641 as a farming community. Lexington is well known as the site of the first shots of the American Revolutionary War, in the Battle of Lexington on April 19, 1775, where the " Shot heard 'round the world" took place. It is home to Minute Man National Historical Park. History Indigenous history Native Americans inhabited the area that would become Lexington for thousands of years prior to European colonization of the Americas, as attested by a woodland era archaeological site near Loring Hill south of the town center. At the time of European contact, the area may have been a border region between Naumkeag or Pawtucket to the northeast, Massachusett to the south, and Nipmuc to the west, though the land was ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Revenue
In accounting, revenue is the total amount of income generated by the sale of goods and services related to the primary operations of the business. Commercial revenue may also be referred to as sales or as turnover. Some companies receive revenue from interest, royalties, or other fees A fee is the price one pays as remuneration for rights or services. Fees usually allow for overhead (business), overhead, wages, costs, and Profit (accounting), markup. Traditionally, professionals in the United Kingdom (and previously the Repu .... This definition is based on International Accounting Standard, IAS 18. "Revenue" may refer to income in general, or it may refer to the amount, in a monetary unit, earned during a period of time, as in "Last year, Company X had revenue of $42 million". Profit (accounting), Profits or net income generally imply total revenue minus total expenses in a given period. In accountancy, accounting, in the balance statement, revenue is a subsection of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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