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991.
Line bundles on non-primary Hopf manifolds 总被引:3,自引:0,他引:3
LIU Weiming & ZHOU XiangyuInstitute of Mathematics Academy of Mathematics System Sciences Chinese Academy of Sciences Beijing China Department of Mathematics Zhejiang University Hangzhou China 《中国科学A辑(英文版)》2004,47(4):538-551
Let X be a Hopf manifolds with Abelian fundamental group, L any flat line bundle on X, we give a formula for computing explicitly the cohomology Hq(X,Ωp(L) using the method of group action and the generalized Douady sequence. 相似文献
992.
L. Knisevskaja M. Tamoinien V. ugurov 《International Journal of Infrared and Millimeter Waves》2002,23(2):325-336
An open microstrip line with a two-layer substrate of SiO2 and Al2O3, employed in millimeter-wave range mikroelectronic devices, has been numerically studied. The dependences of the characteristic electrodynamical properties of this line upon its geometrical parameters were calculated. For computations, the method of singular integral equations in the quasistatic approximation was applied. Double complexity was introduced: with respect to time and to coordinates. This method allows taking into account even very large losses in the material of the microstrip line substrate. The computation algorithm permitted us to take into account the finite strip conductor thickness and substrate width. 相似文献
993.
994.
995.
孔祥艳 《新疆大学学报(理工版)》2008,25(3)
设G是一个图,G的路图P3(G)的顶点集是G中所有三个顶点的路P3, 当G中的两个P3路形成P4路或C3圈时,在P3(G)中它们所代表的两个顶点相邻. 在这篇文章中,我们得到对于一个无三角形的图G, χ(P3(G))≤β(G),其中β(G)表G的点覆盖数. 对于顶点数至少为3的连通图G,χ(P3(G))≤2当且仅当G是二部图, 并且χ(P3(G))=1当且仅当 G是星图. 对于K4的剖分图G,2≤χ(P3(G))≤3. 对于系列平行图和外可平面图G,χ(P3(G))≤3. 相似文献
996.
In this paper, a modified SQP method with nonmonotone line search technique is presented based on the modified quadratic subproblem proposed in Zhou (1997) and the nonmonotone line search technique. This algorithm starts from an arbitrary initial point, adjusts penalty parameter automatically and can overcome the Maratos effect. What is more, the subproblem is feasible at each iterate point. The global and local superlinear convergence properties are obtained under certain conditions. 相似文献
997.
本文结合近年来导电高分子的电化学阻抗谱(EIS)的研究进展,综述了几个EIS理论模型在导电高分子膜研究中的应用和发展。 相似文献
998.
The chirp heterodyne technique allows a directional discrimination of laser Doppler velocity measurements without the use of additional frequency shift elements. This paper presents, for the first time, the use of a chirp frequency-modulated solid-state laser, emitting in the green spectral range. Experimental results of a fluid flow measurement verify the function of the realised chirp heterodyne laser Doppler velocimeter. 相似文献
999.
GENERAL FORM OF MATCHING EQUATION OF ELASTIC-PLASTIC FIELD NEAR CRACK LINE FOR MODEⅠCRACK UNDER PLANE STRESS CONDITION 总被引:2,自引:0,他引:2
Crack line field analysis method has become an independent method for crack elastic-plastic analysis, which greatly simplifies the complexity of crack elastic-plastic problems and overcomes the corresponding mathematical difficulty. With this method, the precise elastic-plastic solutions near crack lines for variety of crack problems can be obtained. But up to now all solutions obtained by this method were for different concrete problems, no general steps and no general form of matching equations near crack line are given out. With crack line analysis method, this paper proposes the general steps of elastic-plastic analysis near crack line for mode Ⅰ crack in elastic-perfectly plastic solids under plane stress condition, and in turn given out the solving process and result for a specific problem. 相似文献
1000.
The multiplication map for global sections of line bundles and rank 1 torsion free sheaves on curves
E Ballico 《Proceedings Mathematical Sciences》2001,111(2):163-172
LetX be an integral projective curve andL ∃ Pica(X),M ∃ Picb (X) with h1(X, L)= h1(X, M) = 0 andL, M general. Here we study the rank of the multiplication map μ
L,M
:H
0(X,L)⊗H
0(X,M)→H
0(X,L⊗M). We also study the same problem whenL andM are rank 1 torsion free sheaves onX. Most of our results are forX with only nodes as singularities. 相似文献