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991.
INDEPENDENT-SET-DELETABLE FACTOR-CRITICAL POWER GRAPHS 总被引:3,自引:0,他引:3
原晋江 《数学物理学报(B辑英文版)》2006,26(4):577-584
It is said that a graph G is independent-set-deletable factor-critical (in short, ID-factor-critical), if, for every independent set 7 which has the same parity as |V(G)|, G-I has a perfect matching. A graph G is strongly IM-extendable, if for every spanning supergraph H of G, every induced matching of H is included in a perfect matching of H. The k-th power of G, denoted by Gk, is the graph with vertex set V(G) in which two vertices are adjacent if and only if they have distance at most k in G. ID-factor-criticality and IM-extendability of power graphs are discussed in this article. The author shows that, if G is a connected graph, then G3 and T(G) (the total graph of G) are ID-factor-critical, and G4 (when |V(G)| is even) is strongly IM-extendable; if G is 2-connected, then D2 is ID-factor-critical. 相似文献
992.
The all-optical recording of a microscopic second-order nonlinear susceptibility in a new azo dye pendant polyurethane polymer is investigated. An experimental configuration which permits self-phase matched was used. The peak value of the phase-matched light-induced second order nonlinear optical susceptibility χ(2) measured at 1.06 μm reaches 62 pm/V at room temperature, which corresponds to a molecular orientation ratio of 30%. Temporal stability of the induced polar order measured by second harmonic generation revealed a reduced decay rate of the χ(2) value in comparison to Disperse Red 1 pendant poly(methyl methacrylate). 相似文献
993.
棉纺厂计算机配棉模型研究 总被引:2,自引:0,他引:2
分析了计算机配棉问题,对配棉的数学模型建立、求解及配棉成纱的质量控制等问题进行了分析研究,研究结果表明,采用计算机配棉管理系统,可以实现配棉过程的科学化管理,提高设计效率. 相似文献
994.
We study generalized approximate weak greedy algorithms. The main difference of these algorithms from approximate weak greedy algorithms proposed by R. Gribonval and M. Nielsen consists in that errors in the calculation of the coefficients can be prescribed in terms of not only their relative values, but also their absolute values. We present conditions on the parameters of generalized approximate weak greedy algorithms which are sufficient for the expansions resulting from the use of this algorithm to converge to the expanded element. It is shown that these conditions cannot be essentially weakened. We also study some questions of the convergence of generalized approximate weak greedy expansions with respect to orthonormal systems.__________Translated from Matematicheskie Zametki, vol. 78, no. 2, 2005, pp. 186–201.Original Russian Text Copyright © 2005 by V. V. Galatenko, E. D. Livshits. 相似文献
995.
设计并实现了一个基于专家系统的网络入侵特征检测系统.针对当前入侵检测推理机制中存在的时间冗余性问题,在入侵检测推理过程中采用了Rete模式匹配算法,对推理机制进行了优化.实验结果表明,该系统在检出率和检测效率上要明显高于未采用Rete模式匹配算法的系统,采用Rete模式匹配算法能有效地克服时间冗余性问题,并改善了系统的性能. 相似文献
996.
Template synthesis of nanostructured silica with hollow core and mesoporous shell structures 总被引:1,自引:0,他引:1
S.B. Yoon J.Y. Kim J.H. Kim S.G. Park J.Y. Kim C.W. Lee J.-S. Yu 《Current Applied Physics》2006,6(6):1059
Silica capsules with hollow macroporous core–mesoporous shell (HCMS) were synthesized through template-assisted replication of submicrometer-size polystyrene spheres as templates. The silica mesoporous shell exhibited highly ordered hexagonal structure as confirmed by X-ray diffraction pattern and TEM image. The pore diameter and BET surface area of this sample were found to be 2.1 nm and 1387 m2/g, respectively. 相似文献
997.
Packing a maximum number of disjoint triangles into a given graph G is NP-hard, even for most classes of structured graphs. In contrast, we show that packing a maximum number of independent
(that is, disjoint and nonadjacent) triangles is polynomial-time solvable for many classes of structured graphs, including
weakly chordal graphs, asteroidal triple-free graphs, polygon-circle graphs, and interval-filament graphs. These classes contain
other well-known classes such as chordal graphs, cocomparability graphs, circle graphs, circular-arc graphs, and outerplanar
graphs. Our results apply more generally to independent packings by members of any family of connected graphs.
Research of both authors is supported by the Natural Sciences and Engineering Research Council of Canada. 相似文献
998.
Cunying Xu Qian Wang Huifang Xu Sishen Xie Zhenzhong Yang 《Colloid and polymer science》2007,285(13):1471-1478
A facile and general approach towards composite hollow ellipsoids has been proposed. The parent polystyrene (PS) hollow spheres
are embedded in a matrix, for example, poly(vinyl alcohol), and stretched into the corresponding ellipsoids. The aspect ratio
of the ellipsoids is tunable by stretching extent. Accordingly, sulfonated PS hollow ellipsoids are achieved by sulfonation
of the PS hollow ellipsoids, which will facilitate an easy complexation with functional materials. Composite hollow ellipsoids,
with varied composition ranging between polymer, metal and oxides, and inorganic materials, are synthesized against the polymer
ellipsoids as templates. By controlling growth of the functional materials at specific sites, structure of the composite hollow
ellipsoids is controlled such as surface-pillared, single-shelled and double-shelled. This approach avoids traditional removal
of polymer templates, thus guarantees the shell integrity of the composite hollow ellipsoids. 相似文献
999.
1000.
本文研究匹配合作对策模型的核心稳定性。基于线性规划对偶理论和图论的相关知识,我们首先证明了匹配对策有稳定核心当且仅当其基础二部图有完美匹配。其次我们讨论了几个与核心稳定性密切相关的性质(核心的包容性、对策的精确性和可扩性)并证明了它们的等价性。基于这些结果,我们还讨论了相应问题的算法。 相似文献