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61.
从速率方程出发对双区共腔(common-cavitytwosection简称CCTS)光双稳激光器进行了精确的理论分析与计算,并对其稳态特性进行了实验研究和测试,得出了定量和定性的分析结果,同时还首次发现当激光输出高态出又出现了一次光双稳和开关效应。经研究确认是量子阱探测器的自电光效应,并提出一种可集成双逻辑功能显示的新型网络模型器件。 相似文献
62.
A pair of primal-dual integer programs is constructed for a class of problems motivated by a generalization of the concept of greatest common divisor. The primal-dual formulation is based on a number-theoretic, rather than a Lagrangian, duality property; consequently, it avoids the dualitygap common to Lagrangian duals in integer programming.This research was partially supported by the National Science Foundation, Grant No. DCR-74-20584 相似文献
63.
In this paper, we present a novel graph-theoretical approach for representing a wide variety of sequence analysis problems
within a single model. The model allows incorporation of the operations “insertion”, “deletion”, and “substitution”, and various
parameters such as relative distances and weights. Conceptually, we refer the problem as the minimum weight common mutated sequence (MWCMS) problem. The MWCMS model has many applications including multiple sequence alignment problem, the phylogenetic analysis, the DNA sequencing
problem, and sequence comparison problem, which encompass a core set of very difficult problems in computational biology.
Thus the model presented in this paper lays out a mathematical modeling framework that allows one to investigate theoretical
and computational issues, and to forge new advances for these distinct, but related problems.
Through the introduction of supernodes, and the multi-layer supergraph, we proved that MWCMS is -complete. Furthermore, it was shown that a conflict graph derived from the multi-layer supergraph has the property that a
solution to the associated node-packing problem of the conflict graph corresponds to a solution of the MWCMS problem. In this
case, we proved that when the number of input sequences is a constant, MWCMS is polynomial-time solvable. We also demonstrated
that some well-known combinatorial problems can be viewed as special cases of the MWCMS problem. In particular, we presented
theoretical results implied by the MWCMS theory for the minimum weight supersequence problem, the minimum weight superstring
problem, and the longest common subsequence problem.
Two integer programming formulations were presented and a simple yet elegant decomposition heuristic was introduced. The integer
programming instances have proven to be computationally intensive. Consequently, research involving simultaneous column and
row generation and parallel computing will be explored. The heuristic algorithm, introduced herein for multiple sequence alignment,
overcomes the order-dependent drawbacks of many of the existing algorithms, and is capable of returning good sequence alignments
within reasonable computational time. It is able to return the optimal alignment for multiple sequences of length less than
1500 base pairs within 30 minutes. Its algorithmic decomposition nature lends itself naturally for parallel distributed computing,
and we continue to explore its flexibility and scalability in a massive parallel environment. 相似文献
64.
在一致凸Banach空间研究了一个新的有限个广义渐近非扩张映射具误差的复合隐迭代过程.利用空间满足Opial条件和算子满足半紧性条件,我们证明了这个隐迭代过程强、弱收敛于有限个广义渐近非扩张映射的公共不动点.这些结果是目前所得成果的完善和推广. 相似文献
65.
Shi Sheng Zhang 《数学学报(英文版)》2010,26(2):337-344
The purpose of this paper is to study the weak convergence problems of the irnplicity iteration process for Lipschitzian pseudocontraction semigroups in general Banach spaces. The results presented in this paper extend and improve the corresponding results of Zhou [Nonlinear Anal., 68, 2977-2983 (2008)], Chen, et ah [J. Math. Anal. Appl., 314, 701 709 (2006)], Xu and Ori [Numer. Funct. Anal. Optim, 22, 767-773 (2001)] and Osilike [J. Math. Anal. Appl., 294, 73-81 (2004)]. Keywords 相似文献
66.
67.
In this paper we introduce a new perturbed proximal-projection algorithm for finding the common element of the set of fixed points of non-expansive mappings and the set of solutions of nonlinear mixed variational-like inequalities. The convergence criteria of the iterative sequences generated by the new iterative algorithm is also given. Our approach and results generalize many known results in this field. 相似文献
68.
本文的目的是研究Lipschitz映射公共不动点问题.基于传统的Ishikawa迭代和Noor迭代方法,我们引入多步Ishikawa迭代算法,并且分别给出了该算法强收敛于有限族拟-Lipschitz映射和伪压缩映射公共不动点的充分必要条件.此外,我们证明了该算法强收敛到非扩张映射的公共不动点.作为应用,我们给出数值试验证实所得的结论. 相似文献
69.
In this paper, we generalize the inclusion constrained longest common subsequence (CLCS) problem to the hybrid CLCS problem which is the combination of the sequence inclusion CLCS and the string inclusion CLCS, called the sequential substring constrained longest common subsequence (SSCLCS) problem. In the SSCLCS problem, we are given two strings A and B of lengths m and n, respectively, formed by alphabet Σ and a constraint sequence C formed by ordered strings (C1,C2,C3,…,Cl) with total length r. The problem is that of finding the longest common subsequence D of A and B containing C1,C2,C3,…,Cl as substrings and with the order of the C’s retained. This problem has two variants, depending on whether the strings in C cannot overlap or may overlap. We propose algorithms with O(mnl+(m+n)(|Σ|+r)) and O(mnr+(m+n)|Σ|) time for the two variants. For the special case with one or two constraints, our algorithm runs in O(mn+(m+n)(|Σ|+r)) or O(mnr+(m+n)|Σ|) time, respectively—an order faster than the algorithm proposed by Chen and Chao. 相似文献
70.
Abstract For relatively prime positive integers u0 and r, and for 0 〈 k ≤ n, define uk := u0 + kr. Let Ln := 1cm(u0,u1,... ,un) and let a,l≥2 be any integers. In this paper, the authors show that, for integers α≥ a, r ≥max(a,l - 1) and n ≥lατ, the following inequality holds Ln≥u0r^(l-1)α+a-l(r+1)^n.Particularly, letting l = 3 yields an improvement on the best previous lower bound on Ln obtained by Hong and Kominers in 2010. 相似文献