Active Sonar
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Active 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 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) to extrem ...
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Dolphin
A dolphin is an aquatic mammal within the infraorder Cetacea. Dolphin species belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontoporiidae (the brackish dolphins), and the extinct Lipotidae (baiji or Chinese river dolphin). There are 40 extant species named as dolphins. Dolphins range in size from the and Maui's dolphin to the and orca. Various species of dolphins exhibit sexual dimorphism where the males are larger than females. They have streamlined bodies and two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can briefly travel at speeds of per hour or leap about . Dolphins use their conical teeth to capture fast-moving prey. They have well-developed hearing which is adapted for both air and water. It is so well developed that some can survive even if they are blind. Some species are well adapted for diving to great depths. The ...
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Morse Code
Morse code is a method used in telecommunication to encode text characters as standardized sequences of two different signal durations, called ''dots'' and ''dashes'', or ''dits'' and ''dahs''. Morse code is named after Samuel Morse, one of the inventors of the telegraph. International Morse code encodes the 26  basic Latin letters through , one accented Latin letter (), the Arabic numerals, and a small set of punctuation and procedural signals ( prosigns). There is no distinction between upper and lower case letters. Each Morse code symbol is formed by a sequence of ''dits'' and ''dahs''. The ''dit'' duration is the basic unit of time measurement in Morse code transmission. The duration of a ''dah'' is three times the duration of a ''dit''. Each ''dit'' or ''dah'' within an encoded character is followed by a period of signal absence, called a ''space'', equal to the ''dit'' duration. The letters of a word are separated by a space of duration equal to three ''dits'', ...
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Newfoundland (island)
Newfoundland (, ; french: link=no, Terre-Neuve, ; ) is a large island off the east coast of the North American mainland and the most populous part of the Canadian province of Newfoundland and Labrador. It has 29 percent of the province's land area. The island is separated from the Labrador Peninsula by the Strait of Belle Isle and from Cape Breton Island by the Cabot Strait. It blocks the mouth of the Saint Lawrence River, creating the Gulf of Saint Lawrence, the world's largest estuary. Newfoundland's nearest neighbour is the French overseas collectivity of Saint Pierre and Miquelon. With an area of , Newfoundland is the world's 16th-largest island, Canada's fourth-largest island, and the largest Canadian island outside the North. The provincial capital, St. John's, is located on the southeastern coast of the island; Cape Spear, just south of the capital, is the easternmost point of North America, excluding Greenland. It is common to consider all directly neighbouring i ...
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Grand Banks
The Grand Banks of Newfoundland are a series of underwater plateaus south-east of the island of Newfoundland on the North American continental shelf. The Grand Banks are one of the world's richest fishing grounds, supporting Atlantic cod, swordfish, haddock and capelin, as well as shellfish, seabirds and sea mammals. Significance The Grand Banks of Newfoundland are a group of underwater plateaus south-east of Newfoundland on the North American continental shelf. These areas are relatively shallow, ranging from in depth. The cold Labrador Current mixes with the warm waters of the Gulf Stream here, often causing extreme foggy conditions. The mixing of these waters and the shape of the ocean bottom lifts nutrients to the surface. These conditions helped to create one of the richest fishing grounds in the world. Fish species include Atlantic cod, swordfish, haddock and capelin; shellfish include scallop and lobster. The area also supports large colonies of seabirds such as north ...
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Boston
Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- most populous city in the country. The city boundaries encompass an area of about and a population of 675,647 as of 2020. It is the seat of Suffolk County (although the county government was disbanded on July 1, 1999). The city is the economic and cultural anchor of a substantially larger metropolitan area known as Greater Boston, a metropolitan statistical area (MSA) home to a census-estimated 4.8 million people in 2016 and ranking as the tenth-largest MSA in the country. A broader combined statistical area (CSA), generally corresponding to the commuting area and including Providence, Rhode Island, is home to approximately 8.2 million people, making it the sixth most populous in the United States. Boston is one of the oldest ...
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Reginald Fessenden
Reginald Aubrey Fessenden (October 6, 1866 – July 22, 1932) was a Canadian-born inventor, who did a majority of his work in the United States and also claimed U.S. citizenship through his American-born father. During his life he received hundreds of patents in various fields, most notably ones related to radio and sonar. Fessenden is best known for his pioneering work developing radio technology, including the foundations of amplitude modulation (AM) radio. His achievements included the first transmission of speech by radio (1900), and the first two-way radiotelegraphic communication across the Atlantic Ocean (1906). In 1932 he reported that, in late 1906, he also made the first radio broadcast of entertainment and music, although a lack of verifiable details has led to some doubts about this claim. Early years Reginald Fessenden was born October 6, 1866, in East Bolton, Quebec, the eldest of the Reverend Elisha Joseph Fessenden and Clementina Trenholme's four children. Elisha ...
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Alexander Behm
Alexander Behm (11 November 1880, in Sternberg (Mecklenburg) – 22 January 1952, in Tarp (Schleswig-Flensburg)) was a German physicist who developed working ocean echo sounder in Germany at the same time Reginald Fessenden was doing so in North America. As head of a research laboratory in Vienna (Austria) he conducted experiments concerning the propagation of sound. He tried to develop an iceberg detection system using reflected sound waves after the Titanic disaster on 15 April 1912. In the end reflected sound waves proved not to be suitable for the detection of icebergs but for measuring the depth of the sea, because the bottom of the sea reflected them well. Thus, echo sounding was born. Behm was granted German patent No. 282009 for the invention of echo sounding ''(device for measuring depths of the sea and distances and headings of ships or obstacles by means of reflected sound waves)'' on 22 July 1913. In 1920 he founded the ''Behm Echo Sounding Company'' in Kie ...
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Lewis Fry Richardson
Lewis Fry Richardson, FRS (11 October 1881 – 30 September 1953) was an English mathematician, physicist, meteorologist, psychologist, and pacifist who pioneered modern mathematical techniques of weather forecasting, and the application of similar techniques to studying the causes of wars and how to prevent them. He is also noted for his pioneering work concerning fractals and a method for solving a system of linear equations known as modified Richardson iteration. Early life Lewis Fry Richardson was the youngest of seven children born to Catherine Fry (1838–1919) and David Richardson (1835–1913). They were a prosperous Quaker family, David Richardson operating a successful tanning and leather-manufacturing business. At age 12 he was sent to a Quaker boarding school, Bootham School in York, where he received an education in science, which stimulated an active interest in natural history. In 1898 he went on to Durham College of Science (a college of Durham University) whe ...
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UK Intellectual Property Office
The Intellectual Property Office of the United Kingdom (often referred to as the UK IPO) is, since 2 April 2007, the operating name of The Patent Office. It is the official government body responsible for intellectual property rights in the UK and is an executive agency of the Department for Business, Energy and Industrial Strategy (BEIS). Responsibilities The IPO has direct administrative responsibility for examining and issuing or rejecting patents, and maintaining registers of intellectual property including patents, designs and trade marks in the UK. As in most countries, there is no statutory register of copyright and the IPO does not conduct any direct administration in copyright matters. The IPO is led by the Comptroller General of Patents, Designs and Trade Marks, who is also Registrar of Trade Marks, Registrar of Designs and Chief Executive of the IPO. Since 1 May 2017, the Comptroller has been Tim Moss, following the resignation of John Alty who had been Comptroller ...
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Patent
A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A patent is not the grant of a right to make or use or sell. It does not, directly or indirectly, imply any such right. It grants only the right to exclude others. The supposition that a right to make is created by the patent grant is obviously inconsistent with the established distinctions between generic and specific patents, and with the well-known fact that a very considerable portion of the patents granted are in a field covered by a former relatively generic or basic patent, are tributary to such earlier patent, and cannot be practiced unless by license thereunder." – ''Herman v. Youngstown Car Mfg. Co.'', 191 F. 579, 584–85, 112 CCA 185 (6th Cir. 1911) In most countries, patent rights fall under private law and the patent holder mus ...
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Lightvessel
A lightvessel, or lightship, is a ship that acts as a lighthouse. They are used in waters that are too deep or otherwise unsuitable for lighthouse construction. Although some records exist of fire beacons being placed on ships in Roman times, the first modern lightvessel was off the Nore sandbank at the mouth of the River Thames in England, placed there by its inventor Robert Hamblin in 1734. The type has become largely obsolete; lighthouses replaced some stations as the construction techniques for lighthouses advanced, while large, automated buoys replaced others. Construction A crucial element of lightvessel design is the mounting of a light on a sufficiently tall mast. Initially, it consisted of oil lamps that could be run up the mast and lowered for servicing. Later vessels carried fixed lamps which were serviced in place. Fresnel lenses were used as they became available, and many vessels housed them in small versions of the lanterns used in lighthouses. Some lightship ...
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