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Topic Review
True Range Multilateration
True range multilateration is a method to determine the location of a movable vehicle or stationary point in space using multiple ranges (distances) between the vehicle/point and multiple spatially-separated known locations (often termed 'stations'). True range multilateration is both a mathematical topic and an applied technique used in several fields. A practical application involving a fixed location is the trilateration method of surveying. Applications involving vehicle location are termed navigation when on-board persons/equipment are informed of its location, and are termed surveillance when off-vehicle entities are informed of the vehicle's location. Two slant-ranges from two known locations can be used to locate a third point in a two-dimensional Cartesian space (plane), which is a frequently applied technique (e.g., in surveying). Similarly, two spherical ranges can be used to locate a point on a sphere, which is a fundamental concept of the ancient discipline of celestial navigation — termed the altitude intercept problem. Moreover, if more than the minimum number of ranges are available, it is good practice to utilize those as well. This article addresses the general issue of position determination using multiple ranges. In two-dimensional geometry, it is known that if a point lies on two circles, then the circle centers and the two radii provide sufficient information to narrow the possible locations down to two – one of which is the desired solution and the other is an ambiguous solution. Additional information often narrow the possibilities down to a unique location. In three-dimensional geometry, when it is known that a point lies on the surfaces of three spheres, then the centers of the three spheres along with their radii also provide sufficient information to narrow the possible locations down to no more than two (unless the centers lie on a straight line). True range multilateration can be contrasted to the more frequently encountered (pseudorange) multilateration, which employs range differences to locate a (typically, movable) point. Pseudo range multilateration is almost always implemented by measuring times-of-arrival (TOAs) of energy waves. True range multilateration can also be contrasted to triangulation, which involves the measurement of angles. Multiple, sometimes overlapping and conflicting terms are employed for similar concepts – e.g., multilateration without modification has been used for aviation systems employing both true ranges and pseudo ranges. Moreover, different fields of endeavor may employ different terms. In geometry, trilateration is defined as the process of determining absolute or relative locations of points by measurement of distances, using the geometry of circles, spheres or triangles. In surveying, trilateration is a specific technique. The term true range multilateration is accurate, general and unambiguous. Authors have also used the terms range-range and rho-rho multilateration for this concept.
  • 1.7K
  • 25 Oct 2022
Topic Review
Korla
Korla (sometimes as Kurla, or Kurle) is the second largest city in Xinjiang, and is, administratively, a county-level city and the seat of the Bayingolin Mongol Autonomous Prefecture, which is larger than Great Britain and is the largest Chinese prefecture. Korla is also known for its "fragrant" pears.
  • 1.7K
  • 26 Oct 2022
Topic Review
List of Minerals Approved by IMA (G)
This list includes those recognised minerals beginning with the letter G. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 1.7K
  • 20 Oct 2022
Topic Review
Mammoth Mountain
Mammoth Mountain is a lava dome complex partially located within the town of Mammoth Lakes, California, in the Inyo National Forest of Madera and Mono Counties. It is home to a large ski area primarily on the Mono County side. Mammoth Mountain was formed in a series of eruptions that ended 57,000 years ago. Mammoth still produces hazardous volcanic gases that kill trees and caused ski patroller fatalities in 2006.
  • 1.7K
  • 01 Dec 2022
Topic Review
Jeannette Expedition
The Jeannette Expedition of 1879–1881, officially called the U.S. Arctic Expedition, was an attempt led by George W. De Long to reach the North Pole by pioneering a route from the Pacific Ocean through the Bering Strait. The premise was that a temperate current, the Kuro Siwo, flowed northwards into the strait, providing a gateway to the Open Polar Sea and thus to the pole. This theory proved illusory; the expedition's ship, USS Jeannette and its crew of 33, was trapped by ice and drifted for nearly two years before she was crushed and sunk, north of the Siberian coast. De Long then led his 32 men on a perilous journey by sled, dragging the Jeannette's whaleboat and two cutters, eventually switching to these small boats to sail for the Lena Delta in Siberia. During this journey, and in the subsequent weeks of wandering in Siberia before rescue, 20 of the ship's complement died, including De Long. The chief exponent of the theory of a warm-water gateway to the North Pole was the German cartographer August Petermann. He encouraged James Gordon Bennett Jr., the proprietor of the New York Herald, to finance a polar expedition based on the untried Pacific route. Bennett acquired a former Royal Navy gunboat, the Pandora, and changed her name to Jeannette. De Long, whom Bennett chose to lead the expedition, was a serving naval officer with previous Arctic experience. Although essentially a private venture, in which Bennett paid all the bills, the expedition had the full support of the U.S. Government. Before departure the ship was commissioned into the U.S. Navy as USS Jeannette, and sailed under navy laws and discipline. Before its demise, the expedition discovered new islands—the De Long Islands—and collected valuable meteorological and oceanographic data. Although Jeannette's fate demolished the widely believed Open Polar Sea theory, the appearance in 1884 of debris from the wreck on the south-west coast of Greenland indicated the existence of an ocean current moving the permanent Arctic ice from east to west. This discovery inspired Fridtjof Nansen to mount his Fram expedition nine years later. A monument to the Jeannette's dead was erected at the United States Naval Academy in Annapolis, in 1890.
  • 1.6K
  • 01 Nov 2022
Topic Review
Martian Atmospheric Noble Gas Measurements
Martian Atmospheric Noble Gas Measurements refer to technologies to measure Martian atmospheric noble gases in situ by entry probes and in laboratory in Martian meteorites.  
  • 1.6K
  • 02 Dec 2020
Topic Review
Hybrid Solar Dryers
Hybrid solar dryers, by definition, designed and constructed using direct solar energy and a heat exchanger. The products are dried under direct solar radiation and/or backup energy or stored heat when sunlight is not available. These types of dryers are used in single and mixed modes of drying. Several studies have been developed to test different techniques to improve solar dryers, considering the possible use of thermal storage materials, the deep bed drying method, improved solar collector designs and energy hybridization. They can be divided several ways, depending on their construction.
  • 1.6K
  • 17 Jan 2024
Topic Review
Changing Food Consumption Patterns and Land Requirements
The food consumed and the household size determine the land requirement for food. Continued population growth without improved living standards and adequate food production output per hectare will further exacerbate food insecurity and land shortage in Nigeria.
  • 1.6K
  • 19 Jan 2022
Topic Review
Yana, India
Yana is a village located in forests of the Sirsi and Kumta Uttara Kannada district of Karnataka, India which is known for the unusual karst rock formations. It is located in the Sahyadri mountain range of the Western Ghats, about 60 kilometres (37 mi) from Karwar port, 39 kilometres (24 mi) from Sirsi, and 31 kilometres (19 mi) from Kumta. Yana is one of the wettest villages in the world. It is the cleanest village in Karnataka, and the second cleanest village in India . The two unique rock outcrops near the village are a tourist attraction and easily approachable by a small trek through 0.5 kilometres (0.31 mi) of thick forests from the nearest road head. Yana is famous for these two massive rock outcrops known as the Bhairaveshwara Shikhara and the Mohini Shikhara ("Shikhara" means "hill"). The huge rocks are composed of solid black, crystalline karst limestone. Bhairaveshwara Shikhara is 120 metres (390 ft) in height, while the Mohini Shikhara, which is smaller, is 90 metres (300 ft) in height. Yana is also well known as a pilgrimage centre because of the cave temple below the Bhairaveshwara Shikhara where a Swayambhu ("self manifested", or "that which is created by its own accord") linga has been formed. Water drips from the roof over the linga, adding to the sanctity of the place. During Shivaratri here, a car festival is held, along with other festivities. The place and its surrounding hillocks are also known for their evergreen scenic forests.
  • 1.6K
  • 14 Oct 2022
Topic Review
Food Systems
The term food system is used frequently in discussions about nutrition, food, health, community economic development and agriculture. A food system includes all processes and infrastructure involved in feeding a population: growing, harvesting, processing, packaging, transporting, marketing, consumption, and disposal of food and food-related items. It also includes the inputs needed and outputs generated at each of these steps. A food system operates within and is influenced by social, political, economic and environmental contexts. It also requires human resources that provide labor, research and education. Food systems are either conventional or alternative according to their model of food lifespan from origin to plate.
  • 1.5K
  • 30 Oct 2022
Topic Review
Education for Environmental Citizenship
Environmental citizenship and environmental education are a particularly special field for the symbolic and practical clashes of competing ideas, interests, and organizations. Smederevac-Lalic et al. explain that formal, informal, and non-formal education are mediators of other types of knowledge and that the perceptions and interests of participants in the three organizational forms also express different intentions and aspirations.
  • 1.5K
  • 14 Dec 2021
Topic Review
Services Accessibility in Rural Areas
The accessibility of services in rural areas can be considered to be one of the most important aspects of the creation of comparable living conditions in the whole territory of Europe. The inaccessibility of services can be considered an important factor of rural deprivation.
  • 1.5K
  • 30 Aug 2021
Topic Review
Carterton, New Zealand
Carterton (Māori: Taratahi) is a small town in the Wellington Region of New Zealand and the seat of the Carterton District (a territorial authority or local government district). It lies in a farming area of the Wairarapa in New Zealand's North Island. It is located 14 km (8.7 mi) southwest of Masterton and 80 km (50 mi) northeast of Wellington. The town has a population of 5,850 (June 2021), out of a total district population of 10,050. Carterton was founded in 1857. Originally known as Three Mile Bush, it served as housing for workers building the road between Wellington and Masterton. It was later renamed after Charles Carter, who was in charge of the building of the Black Bridge over the Waiohine River south of the town. The town describes itself as New Zealand's daffodil capital, holding a Daffodil Festival each year on the second Sunday in September, with the main event taking place at Middle Run along Gladstone Road.
  • 1.5K
  • 27 Oct 2022
Topic Review
Black Sea Climate and Ecology
Short-term climatic variation in the Black Sea region is significantly influenced by the operation of the North Atlantic oscillation, the climatic mechanisms resulting from the interaction between the north Atlantic and mid-latitude air masses. While the exact mechanisms causing the North Atlantic Oscillation remain unclear, it is thought the climate conditions established in western Europe mediate the heat and precipitation fluxes reaching Central Europe and Eurasia, regulating the formation of winter cyclones, which are largely responsible for regional precipitation inputs and influence Mediterranean Sea surface temperatures (SST's). The relative strength of these systems also limits the amount of cold air arriving from northern regions during winter. Other influencing factors include the regional topography, as depressions and storms systems arriving from the Mediterranean are funneled through the low land around the Bosporus, Pontic and Caucasus mountain ranges acting as waveguides, limiting the speed and paths of cyclones passing through the region.
  • 1.5K
  • 25 Nov 2022
Topic Review
Enchanted Rock
Enchanted Rock (16710 Ranch Rd 965, Fredericksburg TX) is a pink granite mountain located in the Llano Uplift approximately 17 miles (27 km) north of Fredericksburg, Texas and 24 miles (39 km) south of Llano, Texas, United States. Enchanted Rock State Natural Area, which includes Enchanted Rock and surrounding land, spans the border between Gillespie County and Llano County, south of the Llano River. Enchanted Rock covers approximately 640 acres (260 ha) and rises approximately 425 feet (130 m) above the surrounding terrain to elevation of 1,825 feet (556 m) above sea level. It is the largest pink granite monadnock in the United States. Enchanted Rock State Natural Area, a part of the Texas state park system, includes 1,644 acres (665 ha). Designated a Recorded Texas Historic Landmark in 1936. In 1971, Enchanted Rock was designated as a National Natural Landmark by the National Park Service. Enchanted Rock was rated in 2017 as the best campsite in Texas in a 50-state survey conducted by Msn.com.
  • 1.5K
  • 02 Nov 2022
Topic Review
List of Minerals Approved by IMA (I)
This list includes those recognised minerals beginning with the letter I. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 1.5K
  • 07 Nov 2022
Topic Review
Cartographic Labeling
{{Multiple issues| Cartographic labeling is a form of typography and strongly deals with form, style, weight and size of type on a map. Essentially, labeling denotes the correct way to label features (points, arcs, or polygons).
  • 1.5K
  • 11 Nov 2022
Topic Review
Pyrolysis of Biosolids to Produce Biochars
Biochar is a solid, charcoal material that can be used in different applications such as its use in agriculture as a soil enhancer in which moisture content is sustained for long periods of times. Biosolids or biosludges will refer to any form of sludge that has undergone some form of treatment (e.g., chemical, biological, heat treatment, etc.) in order to transform it into a less hazardous and organic form. More importantly, there seems to be an inconsistency in defining what classifies as biosolids, hence, a unified definition is established and provided. The aim is to enable the scientific community as a whole to use a standard definition that allows for synergies to take place. Specifically, the pyrolysis process is selected and is known as a thermochemical technique in which heat and an oxygen-free environment facilitate the decomposition of the feedstock into different products, depending on the operating parameters.
  • 1.4K
  • 14 Sep 2022
Topic Review
Page LaPyout (Cartography)
Page layout, also called map layout or map composition, is the part of Cartographic design that involves assembling various map elements on a page. This may include the map image itself, along with titles, legends, scale indicators, inset maps, and other elements. It follows principles similar to page layout in graphic design, such as balance, gestalt, and visual hierarchy. The term map composition is also used for the assembling of features and symbols within the map image itself, which can cause some confusion; these two processes share a few common design principles but are distinct procedures in practice. Similar principles of layout design apply to maps produced in a variety of media, from large format wall maps to illustrations in books to interactive web maps, although each medium has unique constraints and opportunities.
  • 1.4K
  • 24 Oct 2022
Topic Review
Role of ACE2 in Gut
A vital factor of viral pathogenesis involves the angiotensin-converting enzyme-2 (ACE2) cellular receptor, which facilitates entry of the virus into susceptible cells. The receptor-binding domain of the spike protein binds to the ACE2 receptor activating membrane fusion of the virus to the host cell. Subsequently, viral RNA is released into the cytoplasm, and the infection is established. The gut microbiota is shaped by our diet; therefore, a healthy gut is important for optimal metabolism, immunology and protection of the host. 
  • 1.4K
  • 21 Mar 2022
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