一类二次KdV类型水波方程的行波解

应用平面动力系统理论研究了一类非线性KdV方程的行波解的动力学行为．在参数空间的不同区域内,给出了系统存在孤立波解,周期波解,扭子和反扭子波解的充分条件,并计算出所有可能的精确行波解的参数表示．     

具有脉冲扰动的非线性时滞微分方程

本文研究一类脉冲非线性时滞微分方程解的性质，讨论了其解的整体存在性及非振动解的渐近性，也给出了其所有解振动的充分条件．     

关于某类Briot-Bouquet微分方程若干结果的推广

本文研究了某类形式的Briot-Bouquet微分方程的亚纯解结构问题.利用Nevanlinna值分布理论的有关知识,获得了该类微分方程的所有可能形式,以及当方程的阶为偶数时,给出了每一个形式的方程的亚纯解结构,推广了某些特定的Briot-Bouquet微分方程亚纯解结构的一些结果.     

线性规划应用中的优值调整

人教版高中数学试验本第二册 (上 )增加了“简单的线性规划”这部分内容 ,在线性规划的实际应用中 ,理论上得到的最优解有时可能不满足实际要求 ,这时就需要进行优值调整 .本文将归纳优值调整的几种常用方法 ,供参考 .　　一、在可行域内 ,找出可能成为最优解的所有可行解 ,逐个代入目标函数验证 ,确定出实际最优解 .这种方法适用于可行域内这种可能成为最优解的可行解不太多的问题 .例 1　某运输公司有 7辆载重量为 6ｔ的Ａ型卡车和 4辆载重量为 1 0ｔ的Ｂ型卡车 ,有9名驾驶员 .在建筑某段高速公路中 ,此公司承包了每天至少搬运 36 0ｔ沥青…     

一类具偏差变元非线性偏微分方程解的振动性

研究了一类具有偏差变元的非线性偏微分方程解的振动性，获得了方程所有解振动的充分条件。     

具有二重抛物线解的二次系统

本文给出了具有二重抛物线解的二次系统的一般形状，并与具有并重抛物线解的二次系统相比较，证明了具有二重抛物线解的二次系统也有存在极限环的可能的，而且也是唯一的，但是二重抛物线解却是不可能成为二次系统的分界线不的。     

线性规划多重最优解判别准则刍议

本构造了一些线性规划问题来探讨多重最优解的判别准则，补充了现行献中关于多重最优解判别准则描述的不足，并指出多重最优解判别准则在出现退化解时可能失效的例外情况。     

复域双周期Riccati方程解空间极限集的复杂性

研究了一个复域上双周期系数的Riccati方程,证明了其解空间可分成三个不相交的子空间,其中一个子空间为闭集,所有周期解的全解析延拓的闭包包含在这个子空间内并形成一个完备子集。该子集在解的延拓变换群下是最小不变闭集,可能具有分形结构,而任一周期解的全解析延拓均在此子集内稠密。     

变壁厚柱壳的轴对称问题

本文给出了壁厚按二次函数变化的轴对称柱壳的一般解.K.Federhofer[1]曾研究过壁厚按轴向坐标的二次函数变化的轴对称柱壳,并且给出了在某些情况下的解.本文也研究上述壳体.对于所有可能的情况,给出了控制微分方程的齐次解;对于控制微分方程的非齐次项可表示为自变量的多项式或收敛幂级数的情况,给出了方程的特解.     

Jaulent-Miodek方程的行波解分支

利用平面动力系统分支理论研究了耦合的Jaulent-Miodek方程的孤立波及周期波的存在性,求出了分支参数集．在给定的参数条件下,得到了该方程光滑孤立波解及周期行波解的所有可能的显式表达式．     

On the meromorphic solutions of an equation of Hayman

The behavior of meromorphic solutions of differential equations has been the subject of much study. Research has concentrated on the value distribution of meromorphic solutions and their rates of growth. The purpose of the present paper is to show that a thorough search will yield a list of all meromorphic solutions of a multi-parameter ordinary differential equation introduced by Hayman. This equation does not appear to be integrable for generic choices of the parameters so we do not find all solutions—only those that are meromorphic. This is achieved by combining Wiman-Valiron theory and local series analysis. Hayman conjectured that all entire solutions of this equation are of finite order. All meromorphic solutions of this equation are shown to be either polynomials or entire functions of order one.     

非自治ABS方程的双线性化和Casorati行列式解

本文给出可积非自治Adler-Bobenko-Suris(ABS)链方程,并通过适当的变量变换将其转化为非自治离散双线性方程,从而得到Casorati行列式解.为完成解的验证,在附录中,本文给出一系列Casorati行列式平移公式.     

Monotone iterative sequences for nonlinear integro-differential equations of second order

This paper presents an efficient algorithm based on a monotone method for the solution of a class of nonlinear integro-differential equations of second order. This method is applied to derive two monotone sequences of upper and lower solutions which are uniformly convergent. Theorems which list the conditions for the existence of such sequences are presented. The numerical results demonstrate reliability and efficiency of the proposed algorithm.     

Multiple objective minimum cost flow problems: A review

In this paper, theory and algorithms for solving the multiple objective minimum cost flow problem are reviewed. For both the continuous and integer case exact and approximation algorithms are presented. In addition, a section on compromise solutions summarizes corresponding results. The reference list consists of all papers known to the authors which deal with the multiple objective minimum cost flow problem.     

Stability and Optimality of Solutions to Differential Inclusions via Averaging Method

During the last three decades, the averaging method has been successfully applied to a wide range of problems involving differential inclusions, simplifying the study of the systems under consideration. In this work, the main development trends and methods in the application of the averaging method to the study of stability and optimality of solutions to differential inclusions are surveyed. A detailed list of references is given and some examples of applications are presented.     

Minimizing total completion time in a no-wait flowshop with sequence-dependent additive changeover times

This paper addresses the problem of minimizing total completion time in a two-machine no-wait flowshop where setup times of the jobs are sequence-dependent. Optimal solutions are obtained for two special flowshops and a dominance relation is developed for the general problem. Several heuristic algorithms with the computational complexity of O(n²) and O(n³) are constructed. The heuristics consist of two phases: in the first phase a starting list is developed and in the second a repeated insertion technique is applied. Computational experience demonstrates that the concept of repeated insertion application is quite useful for any starting list and that solutions for all starting lists converge to about the same value of less than 1% after a few iterations.     

Tabu Search for the planar three-index assignment problem

Tabu Search is a very effective method for approximately solving hard combinatorial problems. In the current work we implement Tabu Search for solving the Planar Three-Index Assignment Problem. The problem deals with finding the minimum cost assignment between elements of three distinct sets demanding that every pair of elements, each representing a different set, appears in the same solution exactly once. The solutions of the problems correspond to Latin squares. These structures form the basis of the move generation mechanism employed by the Tabu Search procedures. Standard Tabu Search ideas such as candidate move list, variable tabu list size, and frequency-based memory are tested. Computational results for a range of problems of varying dimensions are presented.     

The stable marriage problem with master preference lists

We study variants of the classical stable marriage problem in which the preferences of the men or the women, or both, are derived from a master preference list. This models real-world matching problems in which participants are ranked according to some objective criteria. The master list(s) may be strictly ordered, or may include ties, and the lists of individuals may involve ties and may include all, or just some, of the members of the opposite sex. In fact, ties are almost inevitable in the master list if the ranking is done on the basis of a scoring scheme with a relatively small range of distinct values. We show that many of the interesting variants of stable marriage that are NP-hard remain so under very severe restrictions involving the presence of master lists, but a number of special cases can be solved in polynomial time. Under this master list model, versions of the stable marriage problem that are already solvable in polynomial time typically yield to faster and/or simpler algorithms, giving rise to simple new structural characterisations of the solutions in these cases.     

Tabu Guided Generalized Hill Climbing Algorithms

This paper formulates tabu search strategies that guide generalized hill climbing (GHC) algorithms for addressing NP-hard discrete optimization problems. The resulting framework, termed tabu guided generalized hill climbing (TG²HC) algorithms, uses a tabu release parameter that probabilistically accepts solutions currently on the tabu list. TG²HC algorithms are modeled as a set of stationary Markov chains, where the tabu list is fixed for each outer loop iteration. This framework provides practitioners with guidelines for developing tabu search strategies to use in conjunction with GHC algorithms that preserve some of the algorithms known performance properties. In particular, sufficient conditions are obtained that indicate how to design iterations of problem-specific tabu search strategies, where the stationary distributions associated with each of these iterations converge to the distribution with zero weight on all non-optimal solutions.     

Hashing vectors for tabu search

Tabu search as proposed by Glover [3,4] has proven to be a very effective metaheuristic for hard problems. In this paper we propose that hash functions be used to record the solutions encountered during recent iterations of the search in a long list. Hash values of potential solutions can be compared to the values on the list for the purpose of avoiding cycling. This frees the algorithm designer of the need to consider cycling when creating tabu restrictions based on move attributes. We suggest specific functions that result in very good performance.