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101.
Trust region affine scaling algorithms for linearly constrained convex and concave programs 总被引:4,自引:0,他引:4
We study a trust region affine scaling algorithm for solving the linearly constrained convex or concave programming problem. Under primal nondegeneracy assumption, we prove that every accumulation point of the sequence generated by the algorithm satisfies the first order necessary condition for optimality of the problem. For a special class of convex or concave functions satisfying a certain invariance condition on their Hessians, it is shown that the sequences of iterates and objective function values generated by the algorithm convergeR-linearly andQ-linearly, respectively. Moreover, under primal nondegeneracy and for this class of objective functions, it is shown that the limit point of the sequence of iterates satisfies the first and second order necessary conditions for optimality of the problem. © 1998 The Mathematical Programming Society, Inc. Published by Elsevier Science B.V.The work of these authors was based on research supported by the National Science Foundation under grant INT-9600343 and the Office of Naval Research under grants N00014-93-1-0234 and N00014-94-1-0340. 相似文献
102.
103.
104.
Given an arbitrary real quartic polynomial, we find the exact region containing the coefficients of the polynomial such that
all roots have absolute values less than 1. 相似文献
105.
A laser diode was designed using a method called sampled grating (SG) distributed feedback (DFB), in which the couplings have been distributed in certain regions along the laser cavity (i.e., regions contain grating). These regions play a big role in pushing the main mode to propagate faster than the side mode by increasing the time delay between them. This delay is due to the empty regions (i.e., regions without grating) along the laser cavity. Neither a phase shift nor incomplete grating have been taken into account with the new structure. The theoretical model in the present work is based on the coupled-mode equations which have been solved numerically by the mean of transfer matrix method (TMM). 相似文献
106.
本给出了处理无约束非光滑优化的信赖域算法的一个实施方案。数值实验表明:这种方案是切实可行和可靠的。 相似文献
107.
108.
基于锥模型的一般信赖域算法收敛性分析 总被引:8,自引:0,他引:8
本文给出了锥模型信赖域算法的一般模型,它不仅包含通常的信赖域算法一相当于锥模型算法中bk=0的情形,而且文献[1]的算法也可看作其子类.我们研究这个模型的较强的全局收敛性,并讨论保证算法具有超线性收敛速率的条件,从而推广了文[1]和文[4]中的若干结果. 相似文献
109.
Yu Chen 《Journal of Combinatorial Theory, Series A》2007,114(5):789-808
For a crystallographic root system, dominant regions in the Catalan hyperplane arrangement are in bijection with antichains in a partial order on the positive roots. For a noncrystallographic root system, the analogous arrangement and regions have importance in the representation theory of an associated graded Hecke algebra. Since there is also an analogous root order, it is natural to hope that a similar bijection can be used to understand these regions. We show that such a bijection does hold for type H3 and for type I2(m), including arbitrary ratio of root lengths when m is even, but does not hold for type H4. We give a criterion that explains this failure and a list of the 16 antichains in the H4 root order which correspond to empty regions. 相似文献
110.
Using only one diffractive element, the Talbot interferometer provides a robust and inherently stable method for reproducing fiber Bragg gratings with variable wavelengths, and reduces the complexity of the fiber grating fabrication system. However, the usable length of the grating is limited by the practical length of the mirrors. This paper presents a phase mask with two fixed prisms and two rotational prisms to inscribe fiber Bragg gratings with variable Bragg wavelengths. In this system, the fiber Bragg grating is inscribed by UV interference stripes of 193 nm derived from two rotational prisms and two fixed prisms, where phase mask is used as a beam splitter of ±1 order diffraction light. It is noteworthy that the tunable phase mask interferometer decreases the demand of the length of prism evidently. 相似文献