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71.
In this paper, an extended version of image edge detector using Green's function approach is proposed for detection of edges in the color vector space field. In the proposed method, the relationship between the Red, Green and Blue components is considered to design a differential operator for detection of edges in color images. By using the proposed operator, partial derivatives of all components of color image can simultaneously affect on the edge detection process. Therefore the proposed method can preserve the vector nature of color images during the edge processing stages. Also, the proposed method is compared both quantitatively and qualitatively with other color edge detectors. Experimental results show that the proposed method can efficiently preserve the edges even when the color images corrupted with different levels of noise. 相似文献
72.
Mario Villalobos-Arias Carlos A. Coello Coello Onésimo Hernández-Lerma 《Mathematical Methods of Operations Research》2006,64(2):353-362
In this paper we consider a simulated annealing algorithm for multiobjective optimization problems. With a suitable choice of the acceptance probabilities, the algorithm is shown to converge asymptotically, that is, the Markov chain that describes the algorithm converges with probability one to the Pareto optimal set. 相似文献
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本文用上下解方法,获得半线性次椭圆方程Dirichlet问题的-些存在性结果. 相似文献
76.
Spectral changes of vector Gaussian Schell-model beams passing through an aperture lens 总被引:1,自引:0,他引:1
On the basis of the polarization matrix and propagation equation of the cross-spectral density matrix, the spectral changes in the focal plane of vector Gaussian Schell-model (GSM) beams focused by an aperture lens are studied, where the influence of correlation and polarizer on the behavior of the spectral switch is stressed. It is found that the critical position uc, spectral minimum Smin, and transition height Δ of the spectral switch depend on the auto-correlation but do not depend on the cross-correlation of GSM beams if there is no polarizer. However, in the presence of the polarizer uc, Smin and Δ depend on both auto- and cross-correlations. The polarizer affects the spectral switch of vector GSM beams, whereas it does not affect the spectral switch of scalar GSM beams. 相似文献
77.
Ionel Popescu 《Journal of Functional Analysis》2006,235(1):1-68
In this paper we prove the Morse inequalities in the non-degenerate and degenerate cases. Like the approach of J.-M. Bismut, ours is based on the idea suggested by Witten. In fact, if anything, our approach is closer to Witten's original idea than Bismut's. 相似文献
78.
In this paper, the concepts of quasiconcave set and strictly quasiconcave set are introduced. By using these concepts, we get a new sufficient condition for the efficient outcome set to be connected. This leads to the connectedness of the efficient solution set in strictly quasiconcave vector maximization under the mild condition that the efficient frontier is closed.The authors would like to thank Professor E. U. Choo and the referees for their many valuable comments and helpful suggestions. 相似文献
79.
Feng Cheng Chang 《Applied mathematics and computation》2005,170(2):1135
An efficient technique is developed to simplify the computations in the area of vector analysis. The evaluation of vector algebraic and differential operations becomes more simple and straightforward by simply converting the vector operations into matrix operations. The matrix formulation technique is especially useful when there are mixed coordinate basis involved in the vector operations. 相似文献
80.