Global satellite positioning

In a similar fashion GPS, the global positioning system, uses many satellites to achieve an accurate result (see Figure 5.2). When only a few are above the horizon the position fix is perhaps to the nearest kilometre or so, but if there are eight or more satellites, positions can be fixed to a few metres. So it is clear that whether one modeller is used and several methods, or many modellers and many methods, relying on only a single attempt no matter how complex would be the most risky approach to modelling. 

In recent years, satellite positioning represented by Global Positioning System (GPS) has been in extensive application, and its accuracy and reliability are likely to improve in near future. While some train traffic control systems have already applied GPS as a means of train detection, various technological developments are also under way for the application of GPS. For example, the rotary snow blowers applied the GPS to detect where it locates in the heavy snow. However, if the snow piled up to the GPS antenna, sometimes, the detection is not possible. However, it is unclear what the relationship between the positioning performance of GPS and the depth of piled-up snow to the GPS antennas. This paper reports how dry or wet snow accretion to the GPS antenna decreases the positioning performance. 

Modem satellite networks are inherently three-dimensional. Because the intervisibility is not a requirement for relative satellite positioning, satellite networks can and do contain much longer links and can be much larger in geographical extent. Nowadays, global geodetic networks are constmcted and used for different applications. 

More advanced applications of e-agriculture in farming exist in the use of sophisticated information and communication technologies such as satellite systems, Global Positioning Systems (GPS), and advanced computers and electronic systems to improve the quantity and quality of production (Food and Agriculture Organization of the United Nations 2005). 

A new development in harvest control for better quality of cane and beet has been the use of global positioning systems (GPS) based on satellite navigation facilities.16... 

Global Positioning System (GPS)—A system of satellites whose signals can be used to locate objects on Earth (including below sea level) very precisely. 

A relatively new development in electronically-supported navigation systems, the Global Position Satellite system, seems destined to replace LORAN C. During the years from 1978 through 1995 the United States launched more than two dozen specialized navigational... 

Improvement in the integration of a global positioning system (survey by satellite) data into our system. 

As an oil spill moves with the winds and surface currents, the slick or portions of it may move and responders may not always know its position, especially in darkness or fog. Buoys have been developed that move on the water in a manner similar to oil. These buoys transmit a position signal directly to receivers located on aircraft or ships or to a satellite that corresponds to the position of the oil slick. Some of these buoys receive Global Positioning System (GPS) data from satellites and transmit this with the signal. The position of the spill can then be determined using a remote receiver. For this type of device to be effective, however, the buoy must respond to both the wind and surface currents in the same way as the oil would. Although this precision in response is difficult to achieve, devices are available that can successfully track a range of crude oils and Bunker C. 

GPS Global positioning system used to track the location of mobile object using the satellite. 

Rubidium and cesium are used in very accurate clocks. These clocks have been used to test phenomena predicted by general relativity theory, to investigate changes in the frequencies of pulsars, to track missiles and satellites, and to maintain the extremely accurate time-keeping required by global positioning systems. 

This means of sensory discrimination has practical value when applied to other types of problans. The location of a military target can be based on a combination of electronic anit-ters and receivers. Global positioning (GPS) can be ascertained similarly by comparing transmission times from various transmitting satellites to a receiver on Earth. Other triangulation schemes use the same principle. 

Humans have extended coordination of their movements by technology such as Global Positioning Satellites. 

Hein G W, Landau H, and Blomenhofer H (1990). Determination of instantaneous sea surface, wave heights and ocedn currents using satellite observations of the Global Positioning System. Pres. Int. Symposium on Marine Positioning, Miami, FL 33146, USA, 15 - 19 October 1990. 

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