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91.
A lattice boltzmann model for compressible perfect gas 总被引:1,自引:0,他引:1
A new lattice Boltzmann model for compressible perfect gas is proposed. The numerical example shows that it can be used to
simulate shock wave and contact discontinuity. The results are comparable with those obtained by traditional methods. The
ratio of specific heats γ may be chosen according to the requirement of problems.
The project supported by the National Natural Science Foundation of China 相似文献
92.
On the spectrum of natural frequencies of circular cylindrical shells completely filled with a fluid
The natural frequencies of cylindrical shells filled with a fluid and having the ends either simply supported or clamped are
determined. Conditions are studied under which the natural frequencies of the shell are close or multiple
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 5, pp. 42–49, May 2006. 相似文献
93.
Richard Kueng Holger Rauhut Ulrich Terstiege 《Applied and Computational Harmonic Analysis》2017,42(1):88-116
We study the recovery of Hermitian low rank matrices from undersampled measurements via nuclear norm minimization. We consider the particular scenario where the measurements are Frobenius inner products with random rank-one matrices of the form for some measurement vectors , i.e., the measurements are given by . The case where the matrix to be recovered is of rank one reduces to the problem of phaseless estimation (from measurements ) via the PhaseLift approach, which has been introduced recently. We derive bounds for the number m of measurements that guarantee successful uniform recovery of Hermitian rank r matrices, either for the vectors , , being chosen independently at random according to a standard Gaussian distribution, or being sampled independently from an (approximate) complex projective t-design with . In the Gaussian case, we require measurements, while in the case of 4-designs we need . Our results are uniform in the sense that one random choice of the measurement vectors guarantees recovery of all rank r-matrices simultaneously with high probability. Moreover, we prove robustness of recovery under perturbation of the measurements by noise. The result for approximate 4-designs generalizes and improves a recent bound on phase retrieval due to Gross, Krahmer and Kueng. In addition, it has applications in quantum state tomography. Our proofs employ the so-called bowling scheme which is based on recent ideas by Mendelson and Koltchinskii. 相似文献
94.
Let G be a bridgeless cubic graph. Consider a list of k 1‐factors of G. Let be the set of edges contained in precisely i members of the k 1‐factors. Let be the smallest over all lists of k 1‐factors of G. We study lists by three 1‐factors, and call with a ‐core of G. If G is not 3‐edge‐colorable, then . In Steffen (J Graph Theory 78 (2015), 195–206) it is shown that if , then is an upper bound for the girth of G. We show that bounds the oddness of G as well. We prove that . If , then every ‐core has a very specific structure. We call these cores Petersen cores. We show that for any given oddness there is a cyclically 4‐edge‐connected cubic graph G with . On the other hand, the difference between and can be arbitrarily big. This is true even if we additionally fix the oddness. Furthermore, for every integer , there exists a bridgeless cubic graph G such that . 相似文献
95.
混水平部分因析设计在各类试验中有广泛应用.纯净效应准则是用于选取最优部分因析设计的重要准则之一.本文考虑含有一个八水平因子、一个四水平因子和若干二水平因子的8×4×2~n混水平设计,给出了分辨度为Ⅲ和Ⅳ的该类混水平设计包含纯净两因子交互作用成分最大数的上界和下界.下界通过构造特定设计而得到. 相似文献
96.
On Free Nonlinear Vibrations of Fluid-Filled Cylindrical Shells with Multiple Natural Frequencies 总被引:1,自引:0,他引:1
Nonlinear free vibrations of a cylindrical shell fully filled with a perfect incompressible fluid are studied. The case is
examined where two natural frequencies of the shell are close
__________
Published in Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 127–138, October 2005 相似文献
97.
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100.
简述了几乎完全非线性(APN)多项式函数的研究现状,讨论了两类几乎完全非线性多项式函数间的扩张仿射(EA)等价性,给出了验证EA等价的一般方法. 相似文献