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36-1965: Coordinates : 41°22′51″N 126°30′52″E / 41.38083°N 126.51444°E / 41.38083; 126.51444 Dam on the Chinese-North Korean Border Dam in Ji'an/Chasŏng Unbong Dam/Yunfeng Dam [REDACTED] View of the reservoir from the Chinese-side of the dam [REDACTED] [REDACTED] Location of Unbong Dam/Yunfeng Dam in China Official name 운봉댐,운봉수력발전소,云峰水电站 Country China/North Korea Location Ji'an / Chasŏng Coordinates 41°22′51″N 126°30′52″E / 41.38083°N 126.51444°E / 41.38083; 126.51444 Status Operational Construction began 1959 Opening date 1965 Dam and spillways Type of dam Concrete gravity Impounds Yalu River Height 113.75 m (373 ft) Length 828 m (2,717 ft) Elevation at crest 321.75 m (1,056 ft) Spillway type Overflow, 21 gates Spillway capacity 21,900 m/s (773,391 cu ft/s) Reservoir Total capacity 3,895,000,000 m (3,157,728 acre⋅ft ) Active capacity 2,662,000,000 m (2,158,119 acre⋅ft ) Catchment area 17,572 km (6,785 sq mi) Normal elevation 318.75 m (1,046 ft) Power Station Commission date 1965-67 Hydraulic head 89 m (292 ft) (design) Turbines 4 x 100 MW Francis-type Installed capacity 400 MW The Unbong Dam , or Yunfeng Dam ,
72-505: A tan ϕ {\displaystyle \textstyle {\tan \beta ={\frac {b}{a}}\tan \phi }\,\!} ; for the GRS 80 and WGS 84 spheroids, b a = 0.99664719 {\textstyle {\tfrac {b}{a}}=0.99664719} . ( β {\displaystyle \textstyle {\beta }\,\!} is known as the reduced (or parametric) latitude ). Aside from rounding, this
108-460: A datum transformation such as a Helmert transformation , although in certain situations a simple translation may be sufficient. Datums may be global, meaning that they represent the whole Earth, or they may be local, meaning that they represent an ellipsoid best-fit to only a portion of the Earth. Examples of global datums include World Geodetic System (WGS 84, also known as EPSG:4326 ),
144-608: A point on Earth's surface is the angle east or west of a reference meridian to another meridian that passes through that point. All meridians are halves of great ellipses (often called great circles ), which converge at the North and South Poles. The meridian of the British Royal Observatory in Greenwich , in southeast London, England, is the international prime meridian , although some organizations—such as
180-697: A profound effect on the country's development and people. According to the World Commission on Dams in 2000, there were 22,104 dams over the height of 15 m (49 ft) operating in China. Of the world's total large dams, China accounts for the most – 20 percent of them; 45 percent of which are used for irrigation. Accordingly, the oldest in China still in use belongs to the Dujiangyan Irrigation System which dates back to 256 BC. In 2005, there were over 80,000 reservoirs in
216-473: A region of the surface of the Earth. Some newer datums are bound to the center of mass of the Earth. This combination of mathematical model and physical binding mean that anyone using the same datum will obtain the same location measurement for the same physical location. However, two different datums will usually yield different location measurements for the same physical location, which may appear to differ by as much as several hundred meters; this not because
252-411: Is 6,367,449 m . Since the Earth is an oblate spheroid , not spherical, that result can be off by several tenths of a percent; a better approximation of a longitudinal degree at latitude ϕ {\displaystyle \phi } is where Earth's equatorial radius a {\displaystyle a} equals 6,378,137 m and tan β = b
288-480: Is 110.6 km. The circles of longitude, meridians, meet at the geographical poles, with the west–east width of a second naturally decreasing as latitude increases. On the Equator at sea level, one longitudinal second measures 30.92 m, a longitudinal minute is 1855 m and a longitudinal degree is 111.3 km. At 30° a longitudinal second is 26.76 m, at Greenwich (51°28′38″N) 19.22 m, and at 60° it
324-522: Is 15.42 m. On the WGS 84 spheroid, the length in meters of a degree of latitude at latitude ϕ (that is, the number of meters you would have to travel along a north–south line to move 1 degree in latitude, when at latitude ϕ ), is about The returned measure of meters per degree latitude varies continuously with latitude. Similarly, the length in meters of a degree of longitude can be calculated as (Those coefficients can be improved, but as they stand
360-655: Is a concrete gravity dam on the Yalu River which borders China and North Korea. It is located 33 km (21 mi) northeast of Ji'an in Jilin Province , China and Chasŏng in Chagang Province , North Korea. The primary purpose of the dam is hydroelectric power generation and it supports a 400 MW power station. Construction of the dam had initially began in August 1942 but was halted in 1945 after
396-1174: Is an overflow type with 21 floodgates and has a maximum discharge of 21,900 m/s (773,391 cu ft/s). The dam is located before a bend in the river and its power station is located on the other side of a ridge that meets the dam's right abutment. Water is delivered to the power station via two tunnels, 775 m (2,543 ft) and 759 m (2,490 ft) long. Generators 1 and 3 deliver power to China while 2 and 4 deliver to North Korea. See also [ edit ] [REDACTED] China portal [REDACTED] North Korea portal [REDACTED] Water portal [REDACTED] Renewable energy portal List of dams and reservoirs in China List of major power stations in Jilin References [ edit ] ^ "Yunfeng Hydropower" (in Chinese). Neidri . Retrieved 5 September 2011 . ^ "Yunfeng Hydropower" (in Chinese). Zhejiang College of Water Conservancy and Hydropower. Archived from
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#1732765060631432-507: Is created by the Three Gorges Dam , which stores 39.3 billion m (31,900,000 acre feet) of water and has a surface area of 1,045 km (403 sq mi). Three Gorges is also the world's largest power station. Dams and their associated reservoirs are constructed by the country for several reasons including hydroelectric power generation, flood control , irrigation, drought mitigation, navigation and tourism. China has
468-411: Is different from Wikidata Coordinates on Wikidata Geographic coordinate system A geographic coordinate system ( GCS ) is a spherical or geodetic coordinate system for measuring and communicating positions directly on Earth as latitude and longitude . It is the simplest, oldest and most widely used of the various spatial reference systems that are in use, and forms
504-456: Is known as a graticule . The origin/zero point of this system is located in the Gulf of Guinea about 625 km (390 mi) south of Tema , Ghana , a location often facetiously called Null Island . In order to use the theoretical definitions of latitude, longitude, and height to precisely measure actual locations on the physical earth, a geodetic datum must be used. A horizonal datum
540-754: Is the exact distance along a parallel of latitude; getting the distance along the shortest route will be more work, but those two distances are always within 0.6 m of each other if the two points are one degree of longitude apart. Like any series of multiple-digit numbers, latitude-longitude pairs can be challenging to communicate and remember. Therefore, alternative schemes have been developed for encoding GCS coordinates into alphanumeric strings or words: These are not distinct coordinate systems, only alternative methods for expressing latitude and longitude measurements. List of dams and reservoirs in China Dams and reservoirs in China are numerous and have had
576-465: Is used to precisely measure latitude and longitude, while a vertical datum is used to measure elevation or altitude. Both types of datum bind a mathematical model of the shape of the earth (usually a reference ellipsoid for a horizontal datum, and a more precise geoid for a vertical datum) to the earth. Traditionally, this binding was created by a network of control points , surveyed locations at which monuments are installed, and were only accurate for
612-481: The International Date Line , which diverges from it in several places for political and convenience reasons, including between far eastern Russia and the far western Aleutian Islands . The combination of these two components specifies the position of any location on the surface of Earth, without consideration of altitude or depth. The visual grid on a map formed by lines of latitude and longitude
648-464: The surrender of Japan ending World War II . In October 1959, construction on the dam recommenced and in September 1965, the first of the four 100 MW Francis turbine -generators was operational. The last generator was operational on 4 April 1967. The 113.75 m (373 ft) tall dam creates a reservoir with a storage capacity of 3,895,000,000 m (3,157,728 acre⋅ft ). The dam's spillway
684-526: The 1st or 2nd century, Marinus of Tyre compiled an extensive gazetteer and mathematically plotted world map using coordinates measured east from a prime meridian at the westernmost known land, designated the Fortunate Isles , off the coast of western Africa around the Canary or Cape Verde Islands , and measured north or south of the island of Rhodes off Asia Minor . Ptolemy credited him with
720-506: The Earth's surface move relative to each other due to continental plate motion, subsidence, and diurnal Earth tidal movement caused by the Moon and the Sun. This daily movement can be as much as a meter. Continental movement can be up to 10 cm a year, or 10 m in a century. A weather system high-pressure area can cause a sinking of 5 mm . Scandinavia is rising by 1 cm a year as a result of
756-729: The European ED50 , and the British OSGB36 . Given a location, the datum provides the latitude ϕ {\displaystyle \phi } and longitude λ {\displaystyle \lambda } . In the United Kingdom there are three common latitude, longitude, and height systems in use. WGS 84 differs at Greenwich from the one used on published maps OSGB36 by approximately 112 m. The military system ED50 , used by NATO , differs from about 120 m to 180 m. Points on
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#1732765060631792-536: The French Institut national de l'information géographique et forestière —continue to use other meridians for internal purposes. The prime meridian determines the proper Eastern and Western Hemispheres , although maps often divide these hemispheres further west in order to keep the Old World on a single side. The antipodal meridian of Greenwich is both 180°W and 180°E. This is not to be conflated with
828-714: The Yalu River 1965 establishments in China 1965 establishments in North Korea Buildings and structures in Chagang Province 20th-century architecture in North Korea Hidden categories: Pages using gadget WikiMiniAtlas CS1 Chinese-language sources (zh) All articles with dead external links Articles with dead external links from February 2024 Articles with short description Short description
864-532: The basis for most others. Although latitude and longitude form a coordinate tuple like a cartesian coordinate system , the geographic coordinate system is not cartesian because the measurements are angles and are not on a planar surface. A full GCS specification, such as those listed in the EPSG and ISO 19111 standards, also includes a choice of geodetic datum (including an Earth ellipsoid ), as different datums will yield different latitude and longitude values for
900-577: The center of the Earth. Lines joining points of the same latitude trace circles on the surface of Earth called parallels , as they are parallel to the Equator and to each other. The North Pole is 90° N; the South Pole is 90° S. The 0° parallel of latitude is designated the Equator , the fundamental plane of all geographic coordinate systems. The Equator divides the globe into Northern and Southern Hemispheres . The longitude λ of
936-472: The country and over 4,800 dams completed or under construction that stands at or exceed 30 m (98 ft) in height. As of 2007, China is also the world's leader in the construction of large dams; followed by Turkey , and Japan in third. The tallest dam in China is the Jinping-I Dam at 305 m (1,001 ft), an arch dam , which is also the tallest dam in the world. The largest reservoir
972-649: The default datum used for the Global Positioning System , and the International Terrestrial Reference System and Frame (ITRF), used for estimating continental drift and crustal deformation . The distance to Earth's center can be used both for very deep positions and for positions in space. Local datums chosen by a national cartographical organization include the North American Datum ,
1008-490: The distance they give is correct within a centimeter.) The formulae both return units of meters per degree. An alternative method to estimate the length of a longitudinal degree at latitude ϕ {\displaystyle \phi } is to assume a spherical Earth (to get the width per minute and second, divide by 60 and 3600, respectively): where Earth's average meridional radius M r {\displaystyle \textstyle {M_{r}}\,\!}
1044-474: The full adoption of longitude and latitude, rather than measuring latitude in terms of the length of the midsummer day. Ptolemy's 2nd-century Geography used the same prime meridian but measured latitude from the Equator instead. After their work was translated into Arabic in the 9th century, Al-Khwārizmī 's Book of the Description of the Earth corrected Marinus' and Ptolemy's errors regarding
1080-406: The largest potential for hydropower in the world and currently ranks first in hydroelectric generating capacity with about 200,000 MW online. These benefits have come with adverse effects such as resettlement and inundation while impeding river flow often leads to habitat loss and on certain rivers there are issues with trans-boundary river flow. The nation's leading institution for dam design
1116-781: The length of the Mediterranean Sea , causing medieval Arabic cartography to use a prime meridian around 10° east of Ptolemy's line. Mathematical cartography resumed in Europe following Maximus Planudes ' recovery of Ptolemy's text a little before 1300; the text was translated into Latin at Florence by Jacopo d'Angelo around 1407. In 1884, the United States hosted the International Meridian Conference , attended by representatives from twenty-five nations. Twenty-two of them agreed to adopt
Unbong Dam - Misplaced Pages Continue
1152-461: The location has moved, but because the reference system used to measure it has shifted. Because any spatial reference system or map projection is ultimately calculated from latitude and longitude, it is crucial that they clearly state the datum on which they are based. For example, a UTM coordinate based on WGS84 will be different than a UTM coordinate based on NAD27 for the same location. Converting coordinates from one datum to another requires
1188-595: The longitude of the Royal Observatory in Greenwich , England as the zero-reference line. The Dominican Republic voted against the motion, while France and Brazil abstained. France adopted Greenwich Mean Time in place of local determinations by the Paris Observatory in 1911. The latitude ϕ of a point on Earth's surface is the angle between the equatorial plane and the straight line that passes through that point and through (or close to)
1224-463: The melting of the ice sheets of the last ice age , but neighboring Scotland is rising by only 0.2 cm . These changes are insignificant if a local datum is used, but are statistically significant if a global datum is used. On the GRS 80 or WGS 84 spheroid at sea level at the Equator, one latitudinal second measures 30.715 m , one latitudinal minute is 1843 m and one latitudinal degree
1260-1030: The original on 1 August 2014 . Retrieved 5 September 2011 . ^ "China's highest Concrete Gravity Dams" . Chinese National Committee on Large Dams . Retrieved 5 September 2011 . v t e Hydroelectric dams on the Yalu River [REDACTED] [REDACTED] Unbong Wiwon Sup'ung Taipingwan Retrieved from " https://en.wikipedia.org/w/index.php?title=Unbong_Dam&oldid=1205065187 " Categories : Dams in China Hydroelectric power stations in Jilin Gravity dams Dams in North Korea Hydroelectric power stations in North Korea China–North Korea relations Dams completed in 1965 Dams on
1296-512: The same location. The invention of a geographic coordinate system is generally credited to Eratosthenes of Cyrene , who composed his now-lost Geography at the Library of Alexandria in the 3rd century BC. A century later, Hipparchus of Nicaea improved on this system by determining latitude from stellar measurements rather than solar altitude and determining longitude by timings of lunar eclipses , rather than dead reckoning . In
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