有非更新寿命和成批加工的CIMS的可靠性研究

本文研究了具有非更新寿命和成批加工的CIMS生产线的可靠性问题.首先证明了在系统平稳状态下工作站的广义加工过程是万有马氏过程,然后利用准生灭过程理论,给出了系统稳态时运行指标的精确显式解.从而这使得CIMS生产线中工作站的寿命假定推进到了一类非更新的相型寿命上.     

带缓冲器的多出口串行生产线的无阻塞最优控制

用极大代数方法讨论了带缓冲器的串行生产线的无阻塞最优控制问题,给出了多出口情况下串行生产线的加工状态方程及最优控制。     

多入口多出口串行生产线的最优节奏控制

本文用极大代数方法讨论了多入口多出口情况下带存储器有阻塞串行生产线的最优节奏控制问题,给出了串行生产线的状态方程,批量生产的生产周期公式及其函数形式,最后应用陈文德(1997)提出的算法对生产线实现了最优节奏控制。     

考虑交货期的生产运输联合优化问题研究

结合企业实际场景研究了考虑交货期的多个工厂、多条生产线、单一产品的生产与运输联合优化问题.已知客户订单需求量和交货时间窗,考虑了各条生产线在不同时段的生产能力约束,在满足交货时间窗约束的前提下,以生产、存储、运输费用之和极小化为目标建立了生产与运输联合优化问题的混合整数规划模型,通过分析模型结构证明了在不考虑固定生产成...     

基于质量损失的过程网络及其关键质量链分析

针对传统的过程能力分析仅以生产线中某一单一的生产工序(过程)为对象这一问题,将影响产品质量的所有生产过程视为一个过程网络,根据Taguchi田口方法,阐述了过程能力指数与质量损失的关系,给出了生产制造过程网络过程能力指数的计算方法.进一步应用PERT/CPM的基本思想,建立了生产制造过程网络关键质量链的规划模型,将质量损失最大的路径视为关键质量链.通过实例分析表明,以上方法改进了传统的统计质量控制和分析方法,能够有效地实现过程网络的质量管理.     

一类串行生产线的最优调度问题的注记

本讨论了[1]中串行生产线最优调度问题，给出了生产线生产周期的显示公式，对两个变量时最优调度的解的特性进行了研究。     

一类串行生产线的最优调度问题的注记

本文讨论了文［１］中串行生产线最优调度问题，给出了生产线生产周期的显示公式，对两个变量时最优调度的解的特性进行了研究．     

最优总装线路安排问题研究

本文研究了自动化生产线中总装线路安排的最优化问题,建立了该问题的数学模型,并提出了两个多项式算法．     

多入口无阻塞串行生产线的生产周期

利用极大代数方法讨论多入口串行生产线的生产周期问题,给出在无阻塞控制下的多入口 行生产线生产周期的计算公式及其批量加工生产时的周期公式。     

从后验概率的应用看Bayes概率的意义

某厂有一条自动化生产线，根据以前的经验知它正常运转的概率是９５％。正常运转时生产９０％的合格品，不正常运转时可生产４０％的合格品。某日进行抽样检查，先抽取了一件产品，检验后发现它是合格品；又抽取了一件产品，检验后发现它是废品。根据两次抽样结果推测一下，生产线属于正常运转的概率有多大。这个问题中生产线正常运转的先验概率是９５％，现在产生了新的信息，即两次抽样中一次是合格品，一次是废品，在获取的这种新信息下，再推算生产线正常运转的概率即是后验概率，后验概率可用Ｂａｙｅｓ公式来计算。用Ａ表示生产线正常…     

大型水电工程物资调运建模及算法

根据小湾水电工程物资供应管理的实际情况,提出了物资调运的三级节点概念模型,论述了物资采购与调运的数学模型,并给出了具体算法。模型已应用于该工程物资调运决策支持系统中,运行实践表明,该模型能够辅助调度人员制定合理的物资采购与调运方案。     

A survey of Markov decision models for control of networks of queues

We review models for the optimal control of networks of queues. Our main emphasis is on models based on Markov decision theory and the characterization of the structure of optimal control policies.This research was partially supported by the National Science Foundation under Grant No. DDM-8719825. The Government has certain rights in this material. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. The research was also partially supported by the C.I.E.S. (France), while the author was on leave at INRIA, Sophia-Antipolis, 1991–92.     

Theory and method in history of mathematics

The article argues for the inclusion of material concerning historical theory and method and related vocabulary in beginning history of mathematics courses. A detailed summary of the approach used by the author is provided together with examples and references and assessment of the results.     

Modelling of wave phenomena in the Zahorski material based on modified library for ADINA software

This paper presents numerical modelling of wave phenomena in simple elastic structures such as rods and shields made of hyperelastic Zahorski material. The main difference between the Zahorski material, which is an elastic material in the Green sense, and the commonly used Mooney–Rivlin material lies in the non-linear term including the constant C₃. Consequently, qualitative and quantitative differences are observed compared to the Mooney–Rivlin material, for example in the values of effective stresses. The extension to the ADINA software developed by the author, which helps create 2D and 3D libraries, significantly facilitates modelling of the Zahorski material. The modification can be used for comparison of wave phenomena that are observed during the propagation of disturbances in the Mooney–Rivlin and Zahorski materials. It should be emphasised that the Zahorski material behaves much better at high strains during the analysis of incompressible rubber and rubber-like hyperelastic materials and can be used in various fields of science wherever the model of Mooney–Rivlin material is successfully applied. The results of numerical computations for both Mooney–Rivlin and Zahorski materials were presented in a graphical form and compared in order to illustrate the differences.     

WeightedL p approximation by modified hermite interpolation of higher order

The authors establish necessary and sufficient conditions for the weightedL ^p convergence at given rates of Hermite interpolation of higher order based on Jacobi zeros plus the endpoints ±1. Theorems on simultaneous approximation are also proved.This material is based upon work supported by the Ministero della Università e della Ricerca Scientifica e Tecnologica (the first two authors), by the National Research Council (the second author) and by Hungarian National Foundation Grant No. 1910 (the third author).     

计算方法课程改革的设想与实践

指出了“计算方法”课程的重要性以及该课程的任务、内容及目标,分析了该课程当前教学中存在的问题,给出了改革的设想,如改革课程内容,进行教材建设,改变传统教学方法和加强实践环节等,最后总结了改革的实践效果.     

Stochastic semidefinite programming: a new paradigm for stochastic optimization

Semidefinite programs are a class of optimization problems that have been studied extensively during the past 15 years. Semidefinite programs are naturally related to linear programs, and both are defined using deterministic data. Stochastic programs were introduced in the 1950s as a paradigm for dealing with uncertainty in data defining linear programs. In this paper, we introduce stochastic semidefinite programs as a paradigm for dealing with uncertainty in data defining semidefinite programs.The work of this author was supported in part by the U.S. Army Research Office under Grant DAAD 19-00-1-0465. The material in this paper is part of the doctoral dissertation of this author in preparation at Washington State University.     

Effect of aging on creep of SVAM glass-reinforced plastic in tension with allowance for the orientation of the fibers

The author presents the results of an experimental study of the effect of aging under room conditions on the creep deformation of SVAM glass-reinforced plastic. It is established that with prolongation of the aging period up to two years the resistance of the material to creep deformation increases. The effect of aging is investigated in relation to anisotropy.Mekhanika Polimerov, Vol. 1, No. 6, pp. 20–29, 1965     

Generating optimal multi-segment cutting patterns for circular blanks in the manufacturing of electric motors

The author presents a method to generate optimal multi-segment cutting patterns to improve the material usage of the circular blanks in the manufacturing of rotors and stators of electric motors. In the patterns generated, the sheet is divided into segments with cut lines perpendicular to the sheet length. The width of the segments equals to the sheet width. The lengths of the segments may be different. A segment includes one or more strips that are parallel to the sheet length. More than one row of identical blanks can appear in a strip. The method applies the property of the optimal patterns to reduce the number of segment lengths that should be considered. It uses the knapsack algorithm to determine the optimal arrangement of blanks on each segment and the numbers of the segment lengths in the sheet to make the material usage reach its maximum. The computational results indicate that the method is efficient both in computation time and in material usage. The solution to an example is given.     

合成材料的组成

对工程上所需要的特定材料,若能在理论上预言它并能依理论结果制而即得,乃为工程使用所盼.为此目的,本文即要研究一个合适的理论,选择一些物质组合起来.使作成的合成材料与人们事先所要求的“目标材料”相合.文内前三部分给出理论,第四部分给出结果.并对工程上给定的两种“目标材料”做了理论计算,依计算结果制造了合成材料,且对其做了实验.其结果是满意的.