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排序方式： 共有1737条查询结果，搜索用时 15 毫秒
101.
This paper deals with transformation procedures for observed GPS data from the world geodetic system WGS-84 into the national geodetic grid datum S-UTCN(system of united trigonometric cadaster network) and Baa(the Baltic Sea after adjustment).Transformation from WGS-84 into SUTCN is performed most frequently by means of the 7-element Helmert transformation with three identical points.Geodetic network was adjusted by two ways. 相似文献
102.
Geoid, topography, and the Bouguer plate or shell 总被引：1，自引：1，他引：1
Topography plays an important role in solving many geodetic and geophysical problems. In the evaluation of a topographical
effect, a planar model, a spherical model or an even more sophisticated model can be used. In most applications, the planar
model is considered appropriate: recall the evaluation of gravity reductions of the free-air, Poincaré–Prey or Bouguer kind.
For some applications, such as the evaluation of topographical effects in gravimetric geoid computations, it is preferable
or even necessary to use at least the spherical model of topography. In modelling the topographical effect, the bulk of the
effect comes from the Bouguer plate, in the case of the planar model, or from the Bouguer shell, in the case of the spherical
model. The difference between the effects of the Bouguer plate and the Bouguer shell is studied, while the effect of the rest
of topography, the terrain, is discussed elsewhere. It is argued that the classical Bouguer plate gravity reduction should
be considered as a mathematical construction with unclear physical meaning. It is shown that if the reduction is understood
to be reducing observed gravity onto the geoid through the Bouguer plate/shell then both models give practically identical
answers, as associated with Poincaré's and Prey's work. It is shown why only the spherical model should be used in the evaluation
of topographical effects in the Stokes–Helmert solution of Stokes' boundary-value problem. The reason for this is that the
Bouguer plate model does not allow for a physically acceptable condensation scheme for the topography.
Received: 24 December 1999 / Accepted: 11 December 2000 相似文献
103.
Effects of the spherical terrain on gravity and the geoid 总被引：3，自引：0，他引：3
104.
105.
Levente Füköh 《GeoJournal》1995,36(2-3):255-259
Based on phylogenetical, palaeoecological and biostratigraphical studies on the Holocene malacofauna of Hungarian medium high mountains and flatlands, four faunal periods could be recognised in the mountains, while three ones on the flat regions. They are defined by correlation (using anthracotomical, palynological, vertebrate palaeontological, archaeological and radiometric data, as well as by the Central European malacozones) as biozones of regional value.The mollusc fauna may be regarded as the main palaeoecological indicator for the Hungarian Quaternary, because it is generally abundant, in contrast to the vertebrate fauna. On the other hand, the Hungarian Quaternary fauna mostly consists of species still living in the area. The ecological demands of recent species are generally well known. Most of the ecological data about the Quaternary formations were yielded by the examination of the Hungarian mollusc fauna.The Quaternary mollusc fauna is not only suitable for palaeoecological reconstructions but it helps in the stratigraphical division of the sequences, as well, mainly due to Endre Krolopp's activity (Krolopp 1983). This study and investigations of Holocene molluscs enabled us to make an attempt (Füköh 1990) in describing the history of the last ten thousand years. 相似文献
106.
Studia Geophysica et Geodaetica - 相似文献
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