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111.
J. M. Gushing Shandelle M. Henson 《Journal of Difference Equations and Applications》2013,19(6):859-872
We study a class of periodically forced, monotone difference equations motivated by applications from population dynamics. We give conditions under which there exists a globally attracting cycle and conditions under which the attracting cycle is attenuant 相似文献
112.
Shiying Wang Kai FengShurong Zhang Jing Li 《Applied mathematics and computation》2012,218(9):5409-5413
The class of k-ary n-cubes represents the most commonly used interconnection topology for distributed-memory parallel systems. Given an even k ? 4, let (V1, V2) be the bipartition of the k-ary 2-cube, fv1, fv2 be the numbers of faulty vertices in V1 and V2, respectively, and fe be the number of faulty edges. In this paper, we prove that there exists a cycle of length k2 − 2max{fv1, fv2} in the k-ary 2-cube with 0 ? fv1 + fv2 + fe ? 2. This result is optimal with respect to the number of faults tolerated. 相似文献
113.
Variable neighbourhood search is a metaheuristic used mainly to tackle combinatorial optimization problems. Its performance depends on having a good variable neighbourhood structure: that is, a sequence of neighbourhoods that are ideally pairwise disjoint and contain feasible solutions further and further from a given feasible solution. This article defines a variable neighbourhood structure with these properties that is new for cycle location problems. It find bounds for the neighbourhood sizes and shows how to iterate over then when the cycle is a circuit. It tests the structure and iteration method using variable neighbourhood search on a range of median cycle problems and finds a neighbourhood size beyond which there is, on average, no benefit in applying local search. This neighbourhood size is found not to depend on problem size or bound on circuit length. 相似文献
114.
Yaojun Chen T.C. Edwin Cheng Zhengke Miao C.T. Ng 《Applied Mathematics Letters》2009,22(12):1875-1876
For two given graphs G1 and G2, the Ramsey number R(G1,G2) is the smallest integer n such that for any graph G of order n, either G contains G1 or the complement of G contains G2. Let Cn denote a cycle of order n and Wm a wheel of order m+1. It is conjectured by Surahmat, E.T. Baskoro and I. Tomescu that R(Cn,Wm)=2n−1 for even m≥4, n≥m and (n,m)≠(4,4). In this paper, we confirm the conjecture for n≥3m/2+1. 相似文献
115.
This article is intended as a brief survey of problems and results dealing with cycles containing specified elements of a graph. It is hoped that this will help researchers in the area to identify problems and areas of concentration. 相似文献
116.
117.
基于小波-Contourlet变换的Cycle spinning硬阈值图像去噪方法 总被引:1,自引:1,他引:0
综合考虑小波变换的特点以及Contourlet变换对二维光滑图像有很好的近似特性和对曲线有更好的"稀疏"表示的特点,提出了一种基于小波-Contorlet变换的图像硬阈值去噪方法,并用Cycle spinning去除图像中小波-Con- tourlet变换平移变异性而产生的伪吉布斯现象。实验结果表明:该方法与采用Cycle spinning的小波和Contourlet去嗓算法相比,PSNR分别提高了0.4~1.6和0.2~1.0。与其它去噪算法相比,这种方法能有效地去除图像中的噪声,具有更高的PSNR值,能更好地保留图像的纹理和细节。 相似文献
118.
Jutta Geldermann Nurten Avci Hannes Schollenberger Frank Blümel Otto Rentz 《Macromolecular Symposia》2002,187(1):801-810
Vehicle refinishing body shops are concerned by the environmental policy against photochemical air pollution caused by VOC emissions. For supporting these small enterprises the mass and energy flow model IMPROVE has been developed. Based on an LCA-approach, the process steps of vehicle refinishing are modelled. The model IMPROVE helps to disseminate the consequences of product substitution in comparison to so far used products and techniques in the body shop. For the dissemination of experiences practical guidelines have been developed. Moreover, a comprehensible tool for the Solvent Balance is being offered. Thus, various means are available for consulting and also for strategic production planning for the SME in the sector. 相似文献
119.
该文对一个群体防卫捕一食系统进行了较全面的定性分析.讨论了分界线的相对位置,得到了极限环的存在性、唯一性以及分界线环的存在性,首次证明了群体防卫捕一食系统可以至少存在两个或三个极限环. 相似文献
120.
On the model of the cycle‐plus‐triangles theorem, we consider the problem of 3‐colorability of those 4‐regular hamiltonian graphs for which the components of the edge‐complement of a given hamiltonian cycle are non‐selfcrossing cycles of constant length ≥ 4. We show that this problem is NP‐complete. © 2002 Wiley Periodicals, Inc. J Graph Theory 42: 125–140, 2003 相似文献