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John D. Kraus
John Daniel Kraus (June 28, 1910 – July 18, 2004) was an American physicist known for his contributions to electromagnetics, radio astronomy, and antenna theory. His inventions included the helical antenna, the corner reflector antenna, and several other types of antennas. He designed the Big Ear radio telescope at Ohio State University, which was constructed mostly by a team of OSU students and was used to carry out the Ohio Sky Survey. Kraus held a number of patents and published widely. Personal Kraus was born in 1910 in Ann Arbor, Michigan. He received his Ph.D. in physics from the University of Michigan in 1933. In addition to his professional achievements, he also contributed to amateur radio. His father was scientist Edward Henry Kraus. Before World War II Kraus developed antennas including the corner reflector and W8JK close-spaced array. He also helped construct and operate the University of Michigan 100-ton cyclotron, then the world's most powerful particle ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ann Arbor, Michigan
Ann Arbor is a city in the U.S. state of Michigan and the county seat of Washtenaw County, Michigan, Washtenaw County. The 2020 United States census, 2020 census recorded its population to be 123,851. It is the principal city of the Ann Arbor List of metropolitan statistical areas, Metropolitan Statistical Area, which encompasses all of Washtenaw County. Ann Arbor is also included in the Metro Detroit, Greater Detroit Combined statistical area, Combined Statistical Area and the Great Lakes megalopolis, the most populated and largest Megaregions of the United States, megalopolis in North America. Ann Arbor is home to the University of Michigan. The university significantly shapes Ann Arbor's economy as it employs about 30,000 workers, including about 12,000 in the University of Michigan Health System, medical center. The city's economy is also centered on high technology, with several companies drawn to the area by the university's research and development infrastructure. Ann A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Plain Dealer
''The Plain Dealer'' is the major newspaper of Cleveland, Ohio, United States. In fall 2019, it ranked 23rd in U.S. newspaper circulation, a significant drop since March 2013, when its circulation ranked 17th daily and 15th on Sunday. As of May 2019, ''The Plain Dealer'' had 94,838 daily readers and 171,404 readers on Sunday. ''The Plain Dealers media market, the Cleveland-Akron Designated Market Area, has a population of 3.8 million people, making it the 19th-largest market in the United States. In August 2013, ''The Plain Dealer'' reduced home delivery to four days a week, including Sunday. A daily version of ''The Plain Dealer'' is available electronically as well as in print at stores, newspaper vending machine, newsracks and newsstands. History Founding The newspaper was established in January 1842 when two brothers, Joseph William Gray and Admiral Nelson Gray, took over ''The Cleveland Advertiser'' and changed its name to ''The Plain Dealer''. ''The Cleveland Advertise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen national republics; in practice, both its government and its economy were highly centralized until its final years. It was a one-party state governed by the Communist Party of the Soviet Union, with the city of Moscow serving as its capital as well as that of its largest and most populous republic: the Russian SFSR. Other major cities included Leningrad (Russian SFSR), Kiev (Ukrainian SSR), Minsk ( Byelorussian SSR), Tashkent (Uzbek SSR), Alma-Ata (Kazakh SSR), and Novosibirsk (Russian SFSR). It was the largest country in the world, covering over and spanning eleven time zones. The country's roots lay in the October Revolution of 1917, when the Bolsheviks, under the leadership of Vladimir Lenin, overthrew the Russian Provisional Government ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WWV (radio Station)
WWV is a shortwave ("high frequency" or HF) radio station, located near Fort Collins, Colorado. It has broadcast a continuous time signal since 1945, and implements United States government frequency standards, with transmitters operating on 2.5, 5, 10, 15, and 20 MHz. WWV is operated by the U.S. National Institute of Standards and Technology (NIST), under the oversight of its Time and Frequency Division, which is part of NIST's Physical Measurement Laboratory based in Gaithersburg, Maryland. WWV was established in 1919 by the Bureau of Standards in Washington, D.C., making it one of the oldest continuously-operating radio stations in the United States. NIST celebrated WWV's centennial on October 1, 2019. In 1931, the station relocated to the first of three suburban Maryland sites, before moving to a location near Fort Collins in 1966. WWV shares this site with longwave (also known as "low frequency" or LF) station WWVB, which transmits carrier and time code (no voice) at 60 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Radio Relay League
The American Radio Relay League (ARRL) is the largest membership association of amateur radio enthusiasts in the United States. ARRL is a non-profit organization, and was co-founded on April 6, 1914, by Hiram Percy Maxim and Clarence D. Tuska of Hartford, Connecticut. The ARRL represents the interests of amateur radio operators before federal regulatory bodies, provides technical advice and assistance to amateur radio enthusiasts, supports a number of educational programs and sponsors emergency communications service throughout the country. The ARRL has approximately 161,000 members. In addition to members in the US, the organization claims over 7,000 members in other countries. The ARRL publishes many books and a monthly membership journal called ''QST''. The ARRL is the primary representative organization of amateur radio operators to the US government. It performs this function by lobbying the United States Congress, US Congress and the Federal Communications Commission. The AR ... [...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] |
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage of its active battle fleet alone exceeding the next 13 navies combined, including 11 allies or partner nations of the United States as of 2015. It has the highest combined battle fleet tonnage (4,635,628 tonnes as of 2019) and the world's largest aircraft carrier fleet, with eleven in service, two new carriers under construction, and five other carriers planned. With 336,978 personnel on active duty and 101,583 in the Ready Reserve, the United States Navy is the third largest of the United States military service branches in terms of personnel. It has 290 deployable combat vessels and more than 2,623 operational aircraft . The United States Navy traces its origins to the Continental Navy, which was established during the American Revo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Degaussing
Degaussing is the process of decreasing or eliminating a remnant magnetic field. It is named after the gauss, a unit of magnetism, which in turn was named after Carl Friedrich Gauss. Due to magnetic hysteresis, it is generally not possible to reduce a magnetic field completely to zero, so degaussing typically induces a very small "known" field referred to as bias. Degaussing was originally applied to reduce ships' magnetic signatures during World War II. Degaussing is also used to reduce magnetic fields in cathode ray tube monitors and to destroy data held on magnetic storage. Ships' hulls The term was first used by then-Commander Charles F. Goodeve, Royal Canadian Naval Volunteer Reserve, during World War II while trying to counter the German magnetic naval mines that were wreaking havoc on the British fleet. The mines detected the increase in the magnetic field when the steel in a ship concentrated the Earth's magnetic field over it. Admiralty scientists, including Goodeve, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclotron
A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: January 26, 1932, granted: February 20, 1934 A cyclotron accelerates charged particles outwards from the center of a flat cylindrical vacuum chamber along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying electric field. Lawrence was awarded the 1939 Nobel Prize in Physics for this invention. The cyclotron was the first "cyclical" accelerator. The primary accelerators before the development of the cyclotron were electrostatic accelerators, such as the Cockcroft–Walton accelerator and Van de Graaff generator. In these accelerators, particles would cross an accelerating electric field only once. Thus, the energy gained by the particles was limited by the maximum elec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corner Reflector Antenna
A corner reflector antenna is a type of directional antenna used at VHF and UHF frequencies. It was invented by John D. Kraus in 1938.Kraus, John D., US patent 2270314 Corner reflector antenna filed January 31, 1940; granted January 20, 1942. It consists of a dipole driven element mounted in front of two flat rectangular reflecting screens joined at an angle, usually 90°. Corner reflector antennas have moderate gain of 10–15 dB, high front-to-back ratio of 20–30 dB, and wide bandwidth. Corner reflector antennas are widely used for UHF television receiving antennas, point-to-point communication links and data links for wireless WANs, and amateur radio antennas on the 144, 420, and 1296 MHz bands. They radiate linearly polarized radio waves and can be mounted for either horizontal or vertical polarization. The corner reflector ''antenna'' should not be confused with a ''corner reflector'', a passive device used to reflect radio waves back toward the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Edward Henry Kraus
Edward Henry Kraus (1875–1973) was a Professor of Mineralogy at the University of Michigan and also served as Dean of the Summer Session, 1915–1933, Dean of the College of Pharmacy, 1923–1933, and Dean of the College of Literature, Science and the Arts, 1933–1945. Biography Edward Henry Kraus was born at Syracuse, New York, on December 1, 1875. His father was John Erhardt Kraus, of German ancestry, and his mother, Rosa Kocher Kraus, was of Swiss descent. After training in the high school of Syracuse, he entered Syracuse University, from which he was graduated as Bachelor of Science in 1896. During the following year he was a graduate student in that university and was also an assistant in chemistry and German. He received the degree of Master of Science at the end of the year. For two years, 1897–1899, he was instructor in German and mineralogy at Syracuse. During 1899–1901 he studied at the University of Munich, and at the end of the period received the degree of D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientist
A scientist is a person who conducts Scientific method, scientific research to advance knowledge in an Branches of science, area of the natural sciences. In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engaged in the philosophical study of nature called natural philosophy, a precursor of natural science. Though Thales (circa 624-545 BC) was arguably the first scientist for describing how cosmic events may be seen as natural, not necessarily caused by gods,Frank N. Magill''The Ancient World: Dictionary of World Biography'', Volume 1 Routledge, 2003 it was not until the 19th century in science, 19th century that the term ''scientist'' came into regular use after it was coined by the theologian, philosopher, and historian of science William Whewell in 1833. In modern times, many scientists have Terminal degree, advanced degrees in an area of science and pursue careers in various Sector (economic), sectors of the economy such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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