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41.
Walter Petry 《Astrophysics and Space Science》1986,124(1):63-82
We start from a reference frame for which the pseudo-Euclidean geometry holds, i.e., all laws in have the form of special relativity. The geometry of a reference frame , moving with constant velocity with regard to , is received by using the well-known Galilei-transformation for the covariant space-time vector. In the geometry is different from the pseudo-Euclidean one, i.e., the principle of special relativity does not hold. The velocity of light in is direction dependent but the null result of the Michelson-Morley experiment is received. Several useful transformation formulae are given. In particular, we obtain the Marinov-transformation as transformation from the frame to , and conversely. Maxwell's equations and the equations of motion in the reference frame are given. The theory is applied to some examples, e.g., the Doppler effect, the Fizeau experiment, the field of a charged particle, etc. The method can be generalized to an accelerated reference frame . 相似文献
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Searching for metadata using knowledge bases and topic maps in Spatial Data Infrastructures 总被引:1,自引:1,他引:0
Odilon Corrêa da Silva Jugurta Lisboa-Filho José Luís Braga Karla A. V. Borges 《Earth Science Informatics》2009,2(4):235-247
Concern for environmental issues has become a reality in all sectors of society, mainly among researchers and professionals
who work directly with environmental status. In this context, several studies have been undertaken on sustainable development
of the Brazilian Amazon, generating a large amount of data and information. Environmental area characterization involves the
knowledge about their natural, economic and social resources, as well as understanding the interaction and correlation among
them. Such interdisciplinary character requires new solutions for knowledge representation. This study proposes to minimize
metadata recovery problems in Spatial Data Infrastructures by using Topic Maps and Thesaurus. This approach applied to an
interface aims to allow users to visually recover information from metadata catalogs. 相似文献
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W. Petry 《Astrophysics and Space Science》2000,272(4):353-368
The 1-post-Newtonian approximation of perfect fluid in cosmological models of the theory of gravitation in flat space-time
is studied. The equations of motion are given in evolution form. At high redshifts the terms of post-Newtonian approximation
are important in studying the development of inhomogeneities on scales smaller than galaxies but at present time these terms
only take effect on very large scales.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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48.
The 16 September 2015 Chile Tsunami from the Post-Tsunami Survey and Numerical Modeling Perspectives
49.
Dead stranded sea turtles were recovered and examined to determine the impact of anthropogenic debris and fishery activities on sea turtles on the coast of Rio Grande do Sul State, Brazil. Esophagus/stomach contents of 38 juvenile green Chelonia mydas, 10 adults and sub-adults loggerhead Caretta caretta, and two leatherback Dermochelys coriacea turtles (adult or sub-adult) included plastic bags as the main debris ingested, predominated by white and colorless pieces. The ingestion of anthropogenic debris accounted for the death of 13.2% of the green turtles examined. Signs of damage over the body and carapace indicated that fishing activities caused the death of 13.6% (3/22) of loggerheads and 1.5% (1/56) of green turtles. Therefore, it appears that direct and indirect effects of fishing activities may pose a threat to these species in Brazilian waters. Other sources of plastic debris should be investigated as well as the direct impact of fisheries, especially bottom trawl and gill nets, in order to establish effective conservation action. 相似文献
50.
根据对岩石铸体薄片和阴极发光薄片、地层厚度、古地温梯度以及镜质体反射率等资料分析研究认为:塔中地区东河砂岩经历了压实作用、粘土胶结、石英次生加大、碳酸盐胶结、溶蚀作用、自生高岭石沉淀等多种成岩作用,目前已经达到了晚期成岩阶段。这些成岩作用在塔中4井以东和以西的地区存在较明显的差异,西部进入早成岩阶段B期和晚成岩阶段A期的时间较早,成岩演化程度较高,且具有下部溶蚀上部胶结的分带性;而东部则反之。优质储层主要分布于颗粒成分较纯、泥质含量较低、构造位置上长期处于高部位、被油气充注,但未被晚期碳酸盐胶结的地区。即二叠纪以来长期处于构造高部位的前滨-临滨相带内。 相似文献