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Radio Acoustic Ranging
Radio acoustic ranging, occasionally written as "radio-acoustic ranging" and sometimes abbreviated RAR, was a method for determining a ship's precise location at sea by detonating an explosive charge underwater near the ship, detecting the arrival of the underwater sound waves at remote locations, and Radio transmission, radioing the time of arrival of the sound waves at the remote stations to the ship, allowing the ship's crew to use true range multilateration to determine the ship's position. Developed by the United States Coast and Geodetic Survey in 1923 and 1924 for use in accurately position fix, fixing the position of survey ships during hydrographic survey operations, it was the first navigation technique in human history other than dead reckoning that did not require visual observation of a landmark, marker, light, or celestial body, and the first non-visual means to provide precise positions. First employed operationally in 1924, radio acoustic ranging remained in use un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Acoustic Ranging Graphic
Radio is the technology of telecommunication, communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connected to an antenna (radio), antenna which radiates the waves. They can be received by other antennas connected to a radio receiver; this is the fundamental principle of radio communication. In addition to communication, radio is used for radar, radio navigation, radio control, remote control, remote sensing, and other applications. In radio communication, used in radio and television broadcasting, cell phones, two-way radios, wireless networking, and satellite communication, among numerous other uses, radio waves are used to carry information across space from a transmitter to a receiver, by Modulation, modulating the radio signal (impressing an information signal on the radio wave by varying some aspect of the wave) in the tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronograph
A chronograph is a specific type of watch that is used as a stopwatch combined with a display watch. A basic chronograph has hour and minute hands on the main dial to tell the time, a small seconds hand to tell that the watch is running, and a seconds hand on the main dial usually equipped with a sweeping movement for precision accompanied by a minutes sub dial for the stopwatch. Another sub dial to measure the hours of the stopwatch may also be included on a chronograph. The stopwatch can be started, stopped, and reset to zero at any time by the user by operating pushers usually placed adjacent to the crown. More complex chronographs often use additional complications and can have multiple sub-dials to measure more aspects of the stopwatch such as fractions of a second as well as other helpful things such as the moon phase and the local 24-hour time. In addition, many modern chronographs include tachymeters on the bezels for rapid calculations of speed or distance. Louis M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceberg
An iceberg is a piece of fresh water ice more than long that has broken off a glacier or an ice shelf and is floating freely in open water. Smaller chunks of floating glacially derived ice are called "growlers" or "bergy bits". Much of an iceberg is below the water's surface, which led to the expression " tip of the iceberg" to illustrate a small part of a larger unseen issue. Icebergs are considered a serious maritime hazard. Icebergs vary considerably in size and shape. Icebergs that calve from glaciers in Greenland are often irregularly shaped while Antarctic ice shelves often produce large tabular (table top) icebergs. The largest iceberg in recent history, named B-15, was measured at nearly in 2000. The largest iceberg on record was an Antarctic tabular iceberg measuring sighted west of Scott Island, in the South Pacific Ocean, by the USS ''Glacier'' on November 12, 1956. This iceberg was larger than Belgium. Etymology The word ''iceberg'' is a partial loan tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinking Of The RMS Titanic
RMS ''Titanic'' sank on 15 April 1912 in the North Atlantic Ocean. The largest ocean liner in service at the time, ''Titanic'' was four days into her maiden voyage from Southampton, England, to New York City, USA with an estimated 2,224 people on board when she struck an iceberg at 23:40 ( ship's time) on 14 April. She sank two hours and forty minutes later at 02:20 ship's time (05:18 GMT) on 15 April, resulting in the deaths of more than 1,500 people, making it one of the deadliest peacetime maritime disasters in history. ''Titanic'' received six warnings of sea ice on 14 April, but was travelling at a speed of roughly when her lookouts sighted the iceberg. Unable to turn quickly enough, the ship suffered a glancing blow that buckled the steel plates covering her starboard side and opened six of her sixteen compartments to the sea. ''Titanic'' had been designed to stay afloat with up to four of her forward compartments flooded, and the crew used distress flares and ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Caribbean Sea, and to the south and west by the Pacific Ocean. The region includes Middle America (Americas), Middle America (comprising the Caribbean, Central America, and Mexico) and Northern America. North America covers an area of about , representing approximately 16.5% of Earth's land area and 4.8% of its total surface area. It is the third-largest continent by size after Asia and Africa, and the list of continents and continental subregions by population, fourth-largest continent by population after Asia, Africa, and Europe. , North America's population was estimated as over 592 million people in list of sovereign states and dependent territories in North America, 23 independent states, or about 7.5% of the world's popula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lightvessel
A lightvessel, or lightship, is a ship that acts as a lighthouse. It is 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 lightship was located off the Nore sandbank at the mouth of the River Thames in London, England, by its inventor Robert Hamblin in 1734. Lightships have since been rendered obsolete by advancing lighthouse construction techniques, and by LANBY, large automated navigation buoys. Construction The most important element of lightship design is a tall Mast (sailing), mast upon which to mount the light. Initially, these lights consisted of Oil lamp, oil lamps that were run up the mast and could be lowered for servicing, while later vessels carried fixed lamps which were serviced in place. As they became available, Fresnel lenses were used, and many vessels housed them in smaller versions of lighthouse lanterns. Some lightships ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouse
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lens (optics), lenses and to serve as a beacon for navigational aid for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and the advent of much cheaper, more sophisticated, and more effective electronic navigational systems. History Ancient lighthouses Before the development of clearly defined ports, mariners were guided by fires built on hilltops. Since elevating the fire would improve visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs and promontory, prom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine Signal Company
RTX Corporation, formerly Raytheon Technologies Corporation, is an American multinational aerospace and defense conglomerate headquartered in Arlington, Virginia. It is one of the largest aerospace and defense manufacturers in the world by revenue and market capitalization, as well as one of the largest providers of intelligence services. In 2023, the company's seat in Forbes Global 2000 was 79. RTX manufactures aircraft engines, avionics, aerostructures, cybersecurity solutions, guided missiles, air defense systems, satellites, and drones. The company is a large military contractor, getting much of its revenue from the U.S. government. The company was formed in 2020 by a merger of equals between the aerospace subsidiaries of United Technologies Corporation (UTC) and the Raytheon Company. Before the merger, UTC spun off its non-aerospace subsidiaries Otis Elevator Company and Carrier Corporation. The merged company adopted the better-known name of Raytheon in the form Raytheon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echo Sounding
Echo sounding or depth sounding is the use of sonar for ranging, normally to determine the depth (coordinate), depth of water (bathymetry). It involves transmitting acoustic waves into water and recording the time interval between emission and return of a pulse; the resulting time of flight, along with knowledge of the speed of sound in water, allows determining the distance between sonar and target. This information is then typically used for navigation purposes or in order to obtain depths for Nautical chart, charting purposes. Echo sounding can also be used for ranging to other targets, such as fish schools. Hydroacoustic assessments have traditionally employed mobile surveys from boats to evaluate fish biomass and spatial distributions. Conversely, fixed-location techniques use stationary transducers to monitor passing fish. The word ''Depth sounding, sounding'' is used for all types of depth measurements, including those that don't use sound, and is unrelated in origin to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States East Coast
The East Coast of the United States, also known as the Eastern Seaboard, the Atlantic Coast, and the Atlantic Seaboard, is the region encompassing the coast, coastline where the Eastern United States meets the Atlantic Ocean; it has always played a major socioeconomic role in the development of the United States. The region is generally understood to include the U.S. states that border the Atlantic Ocean: Connecticut, Delaware, Florida, Georgia (U.S. state), Georgia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York (state), New York, North Carolina, Rhode Island, South Carolina, and Virginia, as well as some landlocked territories (Pennsylvania, Vermont, West Virginia and Washington, D.C.). Toponymy and composition The Toponymy, toponym derives from the concept that the contiguous 48 states are defined by two major coastlines, one at the West Coast of the United States, western edge and one on the eastern edge. Other terms for referring to this area include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States West Coast
The West Coast of the United States, also known as the Pacific Coast and the Western Seaboard, is the coastline along which the Western United States meets the North Pacific Ocean. The term typically refers to the contiguous U.S. states of California, Oregon, and Washington, but it occasionally includes Alaska and Hawaii in bureaucratic usage. For example, the U.S. Census Bureau considers both states to be part of a larger U.S. geographic division. Definition There are conflicting definitions of which states comprise the West Coast of the United States, but the West Coast always includes California, Oregon, and Washington as part of that definition. Under most circumstances, however, the term encompasses the three contiguous states and Alaska, as they are all located in North America. For census purposes, Hawaii is part of the West Coast, along with the other four states. ''Encyclopædia Britannica'' refers to the North American region as part of the Pacific Coast, including A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
