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51.
The time delay experiment proposed by I.I. Shapiro in 1964 and conducted in the seventies was the most precise experiment
of general relativity until that time. Further experimentation has improved the accuracy level of both the time delay and
the light deflection experiments. A simulation model is proposed that involves only a simple mass and time transformation
factor involving velocity of light. The light deflection and the time delay experiments are numerically simulated using this
model that does not use the general relativistic equations. The computed values presented in this paper compare well with
recent levels of accuracy of their respective experimental results. 相似文献
52.
Kopcewicz M. Grabias A. Idzikowski B. Williamson D. L. 《Hyperfine Interactions》2002,139(1-4):525-534
The specialized rf-Mössbauer technique is used to elucidate the magnetic properties of NANOPERM-type nanocrystalline alloys. The influence of alloy composition on the soft magnetic properties is studied for the Fe80M7B12Cu1 (M: Ti, Ta, Nb, Mo, Zr) alloys. The rf-Mössbauer experiments allowed us to distinguish magnetically soft nanoclusters from magnetically harder microcrystalline phases. The measurements performed as a function of the rf field intensity allowed the determination of the distribution of anisotropy fields related to the size distribution of bcc nanoclusters. Smaller anisotropy fields in the nanocrystalline phase were found in Nb-, Zr-, and Mo-containing alloys as compared with the alloys which contain Ti and Ta. The Mössbauer measurements were supplemented by X-ray diffraction determination of the size of nanocrystalline grains. 相似文献
53.
We present a network of delay log2N, whose comparators have only log2N different lengths with maximum length N/2. This network is log-sequential in that it will sort N data items when they are passed through it log2Ntimes. The design, which is related to the Batcher odd-even merge, is distinctly different from the first known example of a log-delay log-sequential network, due to Dowd, Perl, Rudolf, and Saks. It is quite probably the best possible sorting network. 相似文献
54.
We compare the two most widely known planarity testing algorithms, the one due to Hoperoft and Tarjan, and the other to Lempel. Even, and Cederbaum. These two algorithms are generally viewed as very different approaches to the problems of planarity testing and graph embedding. In this paper, however, by utilizing previously unnoticed freedoms of choice in the order in which the operations of the Hoperoft-Tarjan algorithm can be performed, we create a variation of this algorithm which, in terms of the order in which vertices are processed, is indistinguishable on all planar graph inputs from the Lempel -Even-Cederbaum algorithm. This allows one to create hybridized algorithms which, when interpreted as embedding algorithms, combine all of the features of both procedures. 相似文献
55.
The ν2 band of H218O occurring in the region 5–7.5 μ was recorded with a high-resolution vacuum infrared spectrograph and an analysis was presented of the rotational structure observed; comparison of the ground state (000) energy levels determined from the ν2 band with those derived earlier by Fraley, Rao, and Jones from the ν1 and ν2 bands at 2.7 μ was of assistance in this analysis. Values for the energy levels of the first excited state (010) were evaluated. 相似文献
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59.
Motivated by heuristic embedding algorithms, this paper is concerned with the organization of potentially large lists of Kuratowski subgraphs of an arbitrary nonpianar graph. A graphical structure called a "nearly Hamiltonian" graph is defined. It is shown that lists of Kuralowski subgraphs can be lexicographically organized in such structures. It is shown that any nonpianar graph contains such structures and at least one such structure with a nonempty list of Kuratowski subgraphs can be located in linear time in ihe edges of the graph. 相似文献
60.
H. Harde H. Burggraf H. W. K. Tom R. K. Jain P. B. Corkum R. S. Taylor Th. Sizer II J. D. Kafka C. Gable G. Mourou D. H. Auston P. R. Smith S. Williamson R. Trebino A. E. Siegman J. Kuhl J. H. Harris S. Sugai A. V. Nurmikko M. G. Li Veerendra K. Mathur Chi H. Lee M. Hasselbach S. C. Hsu H. S. Kwok 《Applied physics. B, Lasers and optics》1982,28(2-3):246-254