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971.
The effect of the nonparallelism of the boundary layer flow over a flat plate on its stability characteristics has been investigated
by several authors, and it was claimed that the results of the theoretical calculations are already in good agreement with
the experimental observations. However, this is not true. In this paper, this problem is reinvestigated, using two different
methods. It is found that within the framework of linear theory, the theoretical results are in fact not in good agreement
with the experimental observations. To settle this problem, nonlinear effect must be taken into consideration.
Projects Supported by the Science Fund of the Chinese Academy of Sciences 相似文献
972.
利用最小调整法求解特殊的二维0-1规划 总被引:1,自引:0,他引:1
具有特殊约束的二维0-1规划的实际应用广泛,在解法中多是应用传统算法,或是在它基础上进行改进,但是此类解法计算繁琐不易推广.针对这种情形,本文引入最小调整法处理此类问题,并将其与传统算法进行对比,充分展示了该方法的优越性,呈现出灵活、方便、简单、易行的特点.通过举例验证了方法的有效性. 相似文献
973.
Konstantin Runovski Hans-Jürgen Schmeisser 《Journal of Fourier Analysis and Applications》2008,14(1):16-38
Means and families of operators generated by Bochner-Riesz kernels are studied. Some sharp results on their convergence are
achieved. The equivalence of the approximation errors of these methods to smoothness quantities related to the Laplacian is
proved.
相似文献
974.
975.
Based on the vectorial Rayleigh–Sommerfeld integrals, the analytical propagation expression of a vectorial Laguerre–Gaussian beam beyond paraxial approximation is presented. The far field expression and the scalar paraxial result are obtained as special cases of the general formulae. According to the analytical representation, the light intensity distribution of the vectorial Laguerre–Gaussian beam is depicted in the reference plane. The light intensity distribution of a vectorial Laguerre–Gaussian beam with cos m is also compared with that of a vectorial Laguerre–Gaussian beam with sin m. 相似文献
976.
A decomposition of the complete 7-partite graph on 28 vertices where each set in the partition has four vertices is given. Several unusual properties of this decomposition are discussed, giving rise to several natural questions. 相似文献
977.
目的是研究局部传递图的性质和分类.运用置换群和陪集图的理论,获得了关于素数立方阶群局部传递图的完全分类,证明了这些图是一些互不相交的关于素数立方阶群边传递图的并. 相似文献
978.
James H. Schmerl 《Mathematical Logic Quarterly》2010,56(5):541-548
The relationship of Grundy and chromatic numbers of graphs in the context of Reverse Mathematics is investi‐gated (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
979.
K. Ya. Kondratyev 《Il Nuovo Cimento C》1990,13(5):835-846
Summary Principal purposes of the International Space Year (ISY) have been discussed. In view of the increasing significance of ecological
problems it is becoming clear that there have to be two key directions of the ISY programmes: 1) various problems relevant
to the International Geosphere-Biosphere Programme (global climate change, global biosphere dynamics, regional ecological
problems: desertification, forest decline, acid rains etc.); 2) comparative planetology. One of the most urgent problems is
connected with the accomplishment, of the ?Mission to Planet Earth? which has to be based on the creation of an optimal global
system of satellite and conventional ecological observations (especially for various typical ecosystems). Studies of the other
planets have to be coordinated with requirements of further investigations in the field of the Earth's ecology. 相似文献
980.
徐新萍 《数学的实践与认识》2009,39(10)
设G是一个图,G的部分平方图G*满足V(G*)=V(G),E(G*)=E(G)∪{uv:uv■E(G),且J(u,v)≠■},这里J(u,v)={w∈N(u)∩N(v):N(w)■N[u]∪N[v]}.利用插点方法,证明了如下结果:设G是k-连通图(k2),b是整数,0min {k,(2b-1+k)/2}(n(Y)-1),则G是哈密尔顿图.同时给出图是1-哈密尔顿的和哈密尔顿连通的相关结果. 相似文献