LP问题的λ算法

本文给出了求LP问题最优解的λ算法,并指出了此法旋转运算的次数.此算法不需要基本可行解或对偶基本可行解.     

LP问题的K算法

本文给出了求 LP问题最优解的λ算法 ,并指出了此法旋转运算的次数 .此算法不需要基本可行解或对偶基本可行解 .     

一种求解延迟工件数最小的混合流水车间调度问题的模拟退火算法

针对延迟工件数最小的混合流水车间调度问题,给出了一种改进的模拟退火求解算法. 该算法首先给出一个启发式算法来获得初始解,然后用模拟退火算法对初始解改进. 通过交换工件在第一阶段的排序来获得一个新的解,采用最先空闲设备分配规则和先到先被加工规则,对工件在剩余各级的工序进行调度. 实验仿真表明算法是可行有效的.     

一个局部带优先权的最大多物资网络流问题

给出一个局部带优先权的最大多物资网络流问题(MMFP-LPRI),证明它的解存在,并给出其η-松弛解的定义.通过做辅助网络,并运用程丛电等根据Korte和Vygen于2000年在Young,Garg和K(o|¨)nemann等工作的基础上给出的求最大多种物资网络流问题的ε-近似解的多项式方案设计的一个算法作为子程序进行二分收索建立了一个求所给问题的η-松弛解的拟多项式算法.最后,进行算法分析,证明了所设计的算法的输出结果确实是MMFP-LPRT的一个η-松弛解.     

非线性演化方程显式精确解的新算法

本文给出了一种求解非线性演化方程的新算法 .将这种算法运用于变形浅水波方程 ,获得了八组显式精确解 ,其中包括新的孤波解和周期解 .借助于 Mathematica软件 ,这种算法能够在 Computer上实现 .     

不等式约束优化问题的低阶精确罚函数的光滑化算法

对不等式约束优化问题提出了一个低阶精确罚函数的光滑化算法. 首先给出了光滑罚问题、非光滑罚问题及原问题的目标函数值之间的误差估计,进而在弱的假
设之下证明了光滑罚问题的全局最优解是原问题的近似全局最优解. 最后给出了一个基于光滑罚函数的求解原问题的算法,证明了算法的收敛性,并给出数值算例说明算法的可行性.     

一个修正的罚函数方法

本文通过给出的一个修正的罚函数,把约束非线性规划问题转化为无约束非线性规划问题.我们讨论了原问题与相应的罚问题局部最优解和全局最优解之间的关系,并给出了乘子参数和罚参数与迭代点之间的关系,最后给出了一个简单算法,数值试验表明算法是有效的.     

由三个特征对构造正定Jacobi矩阵

本文研究了由三个特征对构造正定Jacobi矩阵的问题,给出了这个问题有唯一解的充要条件及解的表达式,并给出了问题的数值算法.     

在两循环矩阵类中求解线性方程组反问题的快速算法

本文利用多项式最大公因式 ,给出了线性方程组的反问题在 r-循环矩阵类和对称 r-循环矩阵类中有唯一解的充要条件 ,进而得到线性方程组在 r循环矩阵类和对称 r-循环矩阵类中的反问题求唯一解的算法 .最后给出了应用该算法的数值例子 .     

丢翻图方x2 + a2=2yn解法的计算研究

本文研究了一类丢番图方程的解.利用对Thue方程解的估计和方程解的连分式展开,获得了所求丢番图方程解的个数、解上界的估计和一般的求解算法.最后利用该算法给出了1≤a≤108的所有解.     

反对称偏对称矩阵反问题的最小二乘解

该文研究了反对称偏对称矩阵反问题的最小二乘解,得到了该问题解的表达式以及该问题有解的充分必要条件.证明了其最佳逼近解的存在性和唯一性,建立了其最佳逼近解的表达式,并给出了求最佳逼近解的数值算法和算例.     

有强化弹塑性含圆孔单向受拉板的渐近解

本文运用有强化弹塑性平面问题的一般渐近解,以解决有强化弹塑性含圆孔的无限大板在单向受拉下的应力分布问题.文中求得了二次近似解的应力分量的解析表达式,并与其他作者的数值计算[4]和实验结果[5]进行了比较,结果颇为符合.最后,作者还就Neuber公式的正确性进行了考查.     

Monotone-iterative method for mixed boundary value problems for generalized difference equations with “maxima”

In this paper the authors investigate special type of difference equations which involve both delays and the maximum value of the unknown function over a past time interval. This type of equations is used to model a real process which present state depends significantly on its maximal value over a past time interval. An appropriate mixed boundary value problem for the given nonlinear difference equation is set up. An algorithm, namely, the monotone iterative technique is suggested to solve this problem approximately. An important feature of our algorithm is that each successive approximation of the unknown solution is equal to the unique solution of an appropriately constructed initial value problem for a linear difference equation with “maxima”, and a formula for its explicit form is given. Also, each approximation is a lower/upper solution of the given nonlinear boundary value problem. Several numerical examples are considered to illustrate the practical application of the suggested algorithm.     

给定零点的指数型整函数Ⅱ

研究了如下问题:给定右半平面一复数列,以该复数列为零点的指数型整函数在虚轴上的增长性有什么表现?并给出了完整的解答.这是对Malliavin和Rubel关于给定右半平面一复数列为零点的指数型整函数性质的研究工作的一个推广.     

抑制剂作用下肿瘤生长模型的参数识别

该文考虑抑制剂作用下肿瘤生长的模型. 假设肿瘤是球对称的, 其表面为运动边界, 用函数r=R(t)表示. 既然多细胞肿瘤扁球体(MTS)通常作为肿瘤生长的体外模型, 在实验室能够被观察和控制, 因此研究如下反问题: 根据观察到的MTS动态增长(即给定R(t)), 来确定抑制剂的参数. 运用极大值原理, 作者证明了该抛物反问题解的唯一性. 进一步, 用最优控制框架来重构模型中的抑制剂参数, 证明了最优控制问题解的存在性, 并推导了最优控制满足的最优性必要条件.     

On a Problem of Solynin

A number of authors have solved the problem of determining the minimal harmonic measure at the origin of a continuum in the closed unit disc which meets every radius. Solynin has given an extension of this problem by requiring that the competing continua have a certain specific index about the origin and has provided an analytically implicit solution. In this paper is given a simpler treatment which leads to a geometrically explicit solution.     

Tree knapsack approaches for local access network design

In the process of solving many forms of the local access network design problem, the basic model of the tree knapsack problem (TKP) is used as a building block for the search engine of the solution strategy. Various solution strategies can be used to solve this problem. An approach that use standard software coupled with enhanced modelling is presented for the TKP. Enhanced modelling is used to partition the TKP into sub-problems that is easier to solve using standard off the shelve software. The basic approach is described and empirical work is presented. Empirical comparisons are also given relating this approach with some algorithms suggested by other authors.     

On the finite element approximation of incompressible flows of an electrically conducting fluid

We consider the finite element approximation of incompressible flows field of an electrically conducing fluid in the presence of a magnetic where it is assumed that this field is prescribed. A weak form is chosen that is similar in some respects to a weak form used by many authors for the Navier-Stokes equations. Existence and uniqueness results are presented for the weak problem. A finite element Algorithm is given for the approximate solution of the weak problem and error estimates are derived.     

Reconstructing (0,1)-matrices from projections using integer programming

We study the problem of reconstructing (0,1)-matrices based on projections along a small number of directions. This discrete inverse problem is generally hard to solve for more than 3 projection directions. Building on previous work by the authors, we give a problem formulation with the objective of finding matrices with the maximal number of neighboring ones. A solution approach based on variable splitting and the use of subgradient optimization is given. Further, computational results are given for some structured instances. Optimal solutions are found for instances with up to 10,000 binary variables.     

Almost global existence for the initial value problem of nonlinear elastodynamic system

The authors deal with the Cauchy problem with small initial data for the nonlinear elastodynamic system. The almost global existence of solution to this problem is proved in a simpler way and a lower bound for the lifespan of solutions is given.