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Keyhole Markup Language
Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization within two-dimensional maps and three-dimensional Earth browsers. KML was developed for use with Google Earth, which was originally named Keyhole Earth Viewer. It was created by Keyhole, Inc, which was acquired by Google in 2004. KML became an international standard of the Open Geospatial Consortium in 2008. Google Earth was the first program able to view and graphically edit KML files, but KML support is now available in many GIS software applications, such as Marble, QGIS, and ArcGIS. Structure The KML file specifies a set of features (place marks, images, polygons, 3D models, textual descriptions, etc.) that can be displayed on maps in geospatial software implementing the KML encoding. Every place has a longitude and a latitude. Other data can make a view more specific, such as tilt, heading, or altitude, which together define a "camera view" along with a timestamp or t ...
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Keyhole, Inc
Google Earth is a web mapping, web and computer program created by Google that renders a 3D computer graphics, 3D representation of Earth based primarily on satellite imagery. The program maps the Earth by superimposition, superimposing satellite images, aerial photography, and geographic information system, GIS data onto a 3D globe, allowing users to see cities and landscapes from various angles. Users can explore the globe by entering addresses and coordinates, or by using a Computer keyboard, keyboard or computer mouse, mouse. The program can also be downloaded on a smartphone or Tablet computer, tablet, using a touch screen or stylus to navigate. Users may use the program to add their own data using Keyhole Markup Language and upload them through various sources, such as forums or blogs. Google Earth is able to show various kinds of images overlaid on the surface of the Earth and is also a Web Map Service client. In 2019, Google revealed that Google Earth covers more than 97 ...
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EGM96
The Earth Gravitational Models (EGM) are a series of geopotential models of the Earth published by the National Geospatial-Intelligence Agency (NGA). They are used as the geoid reference in the World Geodetic System. The NGA provides the models in two formats: as the series of numerical coefficients to the spherical harmonics which define the model, or a dataset giving the geoid height at each coordinate at a given resolution. Three model versions have been published: EGM84 with n=m=180, EGM96 with n=m=360, and EGM2008 with n=m=2160. n and m are the degree and orders of harmonic coefficients; the higher they are, the more parameters the models have, and the more precise they are. EGM2008 also contains expansions to n=2190. Developmental versions of the EGM are referred to as Preliminary Gravitational Models (PGMs). Each version of EGM has its own EPSG Geodetic Parameter Dataset code as a vertical datum. History EGM84 The first EGM, EGM84, was defined as a part of WGS8 ...
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Point Of Interest
A point of interest (POI) is a specific point location that someone may find useful or interesting. An example is a point on the Earth representing the location of the Eiffel Tower, or a point on Mars representing the location of its highest mountain, Olympus Mons. Most consumers use the term when referring to hotels, campsites, fuel stations or any other categories used in modern automotive navigation systems. Users of a mobile device can be provided with geolocation and time-aware POI service that recommends geolocations nearby and with a temporal relevance (e.g. POI to special services in a ski resort are available only in winter). The term is widely used in cartography, especially in electronic variants including GIS, and GPS navigation software. In this context the synonym waypoint is common. A GPS point of interest specifies, at minimum, the latitude and longitude of the POI, assuming a certain map datum. A name or description for the POI is usually included, and othe ...
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NASA WorldWind
NASA WorldWind is an open-source (released under the NOSA license and the Apache 2.0 license) virtual globe. According to the website, "WorldWind is an open source virtual globe API. WorldWind allows developers to quickly and easily create interactive visualizations of 3D globe, map and geographical information. Organizations around the world use WorldWind to monitor weather patterns, visualize cities and terrain, track vehicle movement, analyze geospatial data and educate humanity about the Earth." It was first developed by NASA in 2003 for use on personal computers and then further developed in concert with the open source community since 2004. a web-based version of WorldWind is available online. An Android version is also available. The original version relied on .NET Framework, which ran only on Microsoft Windows. The more recent Java version, WorldWind Java, is cross platform, a software development kit (SDK) aimed at developers and, unlike the old .NET vers ...
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GeoJSON
GeoJSON is an open standard format designed for representing simple geographical features, along with their non-spatial attributes. It is based on the JSON format. The features include points (therefore addresses and locations), line strings (therefore streets, highways and boundaries), polygons (countries, provinces, tracts of land), and multi-part collections of these types. GeoJSON features are not limited to representing entities of the physical world only; mobile routing and navigation apps, for example, might describe their service coverage using GeoJSON. The GeoJSON format differs from other geographic information system standards in that it was written and is maintained not by a formal standards organization, but by an Internet working group of developers. A notable offspring of GeoJSON is TopoJSON, an extension of GeoJSON that encodes geospatial topology and that typically provides smaller file sizes. History The GeoJSON format working group and discussion were b ...
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CityGML
CityGML is an open standardised data model and exchange format to store digital 3D city models, 3D models of cities and Digital elevation model, landscapes. It defines ways to describe most of the common 3D features and objects found in cities (such as buildings, roads, rivers, bridges, vegetation and city furniture) and the relationships between them. It also defines different standard Level of detail (computer graphics), levels of detail (LoDs) for the 3D objects, which allows the representation of objects for different applications and purposes, such as simulations, urban data mining, facility management, and thematic inquiries. CityGML is implemented as a GML application schema for the Geography Markup Language 3 (GML3), the extendible international standard for spatial data exchange issued by the Open Geospatial Consortium (OGC) and the ISO TC211. Implementations In its most common implementation, which is the one generally used to disseminate and exchange data, CityGML data ...
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Brian McClendon
Brian A McClendon (born 1964) is an American software executive, engineer, and inventor. He was a co-founder and angel investor in Keyhole, Inc., a geospatial data visualization company that was purchased by Google in 2004 to produce Google Earth. Keyhole itself was spun off from another company called Intrinsic Graphics, of which McClendon was also a co-founder. McClendon was elected a member of the National Academy of Engineering in 2015 for strategic, technical, and managerial leadership resulting in widespread accurate and useful geographic information. Early life McClendon grew up in Lawrence, Kansas. His childhood home, Meadowbrook Apartments in Lawrence, is the default center point of Google Earth. He graduated from Lawrence High School in 1982 and from the University of Kansas in 1986 with a degree in electrical engineering. Career Early years McClendon spent eight years with Silicon Graphics developing high-end workstation 3D graphics including GT, GTX, RealityEngin ...
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ALOHAnet
ALOHAnet, also known as the ALOHA System, or simply ALOHA, was a pioneering computer networking system developed at the University of Hawaii. ALOHAnet became operational in June 1971, providing the first public demonstration of a wireless packet data network. The ALOHAnet used a new method of medium access, called ''ALOHA random access'', and experimental ultra high frequency (UHF) for its operation. In its simplest form, later known as Pure ALOHA, remote units communicated with a base station (Menehune) over two separate radio frequencies (for inbound and outbound respectively). Nodes did not wait for the channel to be clear before sending, but instead waited for acknowledgement of successful receipt of a message, and re-sent it if this was not received. Nodes would also stop and re-transmit data if they detected any other messages while transmitting. While simple to implement, this results in an efficiency of only 18.4%. A later advancement, Slotted ALOHA, improved the effi ...
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