考虑货架存放期的经济批量排产问题的求解

在化工、造纸、制药、钢铁等工业生产中，一台设备或一条生产线可以生产多种产品的情况很常见。在生产中，如何安排各类产品的生产顺序以及生产数量显得十分重要。这类问题通常称作经济批量排产问题，这类问题是生产库存中的经典问题。本文研究的经济批量排产问题考虑了产品货架存放期因素，针对以往研究的不足，本文提出用批量变动方法求解该类问题，由计算结果显示，按照这种排产方法花费的成本要低于其他两种经济批量排产问题常用的方法。     

能力受限的批量问题的数学模型与算法新进展

古典库存问题和能力无限的单层批量问题的研究已经有几十年的历史了，但由于实际生产中产品结构往往比较复杂、生产能力总有限的，因此能力受限的批量问题（尤其是多层批量问题）成为了近年来运筹学、管理科学和工业工程等领域的研究热点之一。本文在综合大量国内外有关文献的基础上，对一般批量问题的数学模型作了比较系统，全面的介绍，重点讨论能力受限的单层批量问题和多层批量问题的一些新算法，并指出一些值得深入研究和努力实     

需求不确定情况下的多周期生产批量决策

针对在市场需求不确定的情况下的中小制造型企业的生产批量决策优化问题进行研究,根据多周期生产情况下需求的不确定性,综合考虑缺货成本、库存成本和期初库存等因素,以多生产周期的总利润最大化为目标,建立生产批量决策模型,通过优化分析,得出其利润最大化下的最优生产批量,并通过敏感性分析讨论最优批量与多周期生产条件下的不确定需求等影响因素之间的关系.     

原材料易变质和产成品有保质期的生产库存模型研究

考虑需求是时间的线性函数,原材料和产成品的变质率也是时间的线性函数,建立了原材料易变质和产成品有保质期的生产库存模型.用进化规划算法对模型进行求解,确定最佳订购周期,原材料的经济订购批量和产成品的经济生产批量.最后,用具体的数值例子验证了模型与算法的有效性.     

一类存贮模型及其最优存贮策略

当工厂仓库容量有限时,常常需要租借仓库来进行存贮.但是,由于租借仓库的存贮单价通常比自己仓库的存贮单价高,所以不能用经典的经济批量公式来计算,有必要重新进行研究.本文研究了原料仓库和产品仓库容量均有限条件下的定料生产销售存贮问题,建立了相应的存贮模型,给出了最优定料生产存贮策略.     

时值与增加量折扣并允许短缺的变质性物品的EOQ模型

本文在考虑资金时值和增加量折扣的情形下，讨论了允许短缺的变质性物品在有限计划期内的经济批量问题，提供了寻求最优计货次数以及各次订货的最优批量和最优时刻的一个简单的一维方法，并出示了一个数字例子来说明本模型及其求解过程。     

时值与增加量折扣并允许短缺的变质性物品的EOQ模型(英)

本文在考虑资金时值和增加量折扣的情形下，讨论了允许短缺的变质性物品在有限计划期内的经济批量问题，提供了寻求最优计货次数以及各次订货的最优批量和最优时刻的一个简单的一维方法，并出示了一个数字例子来说明本模型及其求解过程．     

存货采购批量的灵敏度分析

本文由经济批量基本模型的灵敏度分析，探讨了模型参数对批量及存货成本的动态影响，为企业合理调查采购批量，节约流动资金占用提供了一条有效途径     

考虑货架存放期的经济批量排产问题的改良算法

经济批量排产问题是关于在单一设备上协调地、周期性地生产多种产品的问题.其解要求在生产准备与库存总成本最小的条件下,决定 I 种产品的生产序列.本文研究的经济批量排产问题考虑了产品货架存放期因素.指出了Dobson算法的不足,并提出了求解该问题的新算法(改进的装箱算法),新算法不仅以生产次数最大的产品为基础进行装箱,而且进一步以生产次数略低的产品为基础进行装箱.排产时,先按生产次数降序进行装箱,再按单次生产时间与生产准备时间之和降序装箱.计算结果显示,本算法结果更优.     

考虑事故风险损失的爆炸物品经济生产批量模型研究

爆炸物品在储存过程中容易发生爆炸事故,因此爆炸物品生产企业对其生产批量进行决策时必需考虑由此带来的风险损失.在给出爆炸物品事故风险损失度量方法的基础上,建立了爆炸物品的经济生产批量模型,并利用Matlab软件给出了模型的求解方法.为相关企业合理制定生产批量决策提供了理论依据.     

Border bases and kernels of homomorphisms and of derivations

Border bases are an alternative to Gröbner bases. The former have several more desirable properties. In this paper some constructions and operations on border bases are presented. Namely; the case of a restriction of an ideal to a polynomial ring (in a smaller number of variables), the case of the intersection of two ideals, and the case of the kernel of a homomorphism of polynomial rings. These constructions are applied to the ideal of relations and to factorizable derivations.     

制造商与销售商双向选择与利益分配

分别建立制造商和销售商主导的供应链的利润分配模型,阐明为什么制造商和销售商都努力使自己成为供应链的主导企业,说明销售商主导型供应链竞争存在优势的原因.制造商主导的供应链中,制造商通过决定产品的批发价格最优化自身的利润分配;在销售商主导的供应链中,销售商通过决定批量折扣率达到对产品批发价格的控制,为销售商带来更大的利润.制造商和销售商在各自主导供应链的利润分配均大于供应链总体利润最大时的利润平均分配.给出一个具体的算例验证模型的结论.     

钢管订购与运输问题三的数学模型与灵敏度分析

本文针对 2 0 0 0年全国大学生数学建模竞赛 B题——钢管订购与运输问题的问题 ( 3) ,建立了数学模型 ,给出了该数学模型的精确求解 .然后对问题 ( 1 )与问题 ( 3)给出了灵敏度分析 .     

Crossings and nestings of matchings and partitions

We present results on the enumeration of crossings and nestings for matchings and set partitions. Using a bijection between partitions and vacillating tableaux, we show that if we fix the sets of minimal block elements and maximal block elements, the crossing number and the nesting number of partitions have a symmetric joint distribution. It follows that the crossing numbers and the nesting numbers are distributed symmetrically over all partitions of , as well as over all matchings on . As a corollary, the number of -noncrossing partitions is equal to the number of -nonnesting partitions. The same is also true for matchings. An application is given to the enumeration of matchings with no -crossing (or with no -nesting).

     

Semantics and pragmatics of fuzzy sets and systems

A philosophical formalism of a new methodological aspect of humanistic systems design and evaluation is given. A requisite concept of context-dependency is highlighted, and some approaches to fuzzy sets and linguistics subsequently extended. It is consequently shown that a mathematical theory of pragmatic fuzzy subsets is not only conceptually possible but practically implementable in man-machine studies as well. Thus, the important context-dependent implication of the subjective nature of Zadeh's theory of fuzzy sets can be better exploited.As a pragmatic theory, the approach here is a seeming connection between pragmatism and ontology, concepts that are traditionally diametrically opposed to each other. The attitude adopted has been the equation of pragmatism and psychophysical measurements of ontological objects (noumena). Pragmatism is tacitly defined as a form of empiricism whereby linguistic constructs (i.e., linguistic-variable denotions) that represent any aspect(s) of a humanistic system are nothing more than an operational procedure used to achieve psychophysical measurements of the aspect(s). In this fashion, pragmatism would enable the contents of assertions, which are made through declarative propositions, about humanistic systems to be deciphered within relevant contexts. For pragmatism, direct sense experience provides both the meaning and the criterion of reality judgements. The context-dependent nature of the physical reality of ontological entities is, therefore, better understood pragmatically vis-a-vis the appropriate evaluative criteria and interpretative conventions.By emphasizing the distinction between a fuzzy system (naturally fuzzified) and a fuzzified mathematical structure (meta-mathematically fuzzified), the use of the standard fuzzy topologies is justified although it is conceptually possible to develop a yet more general topology or perhaps an alternative one especially in the case of a meta-mathematically fuzzified structure. However, for the express purpose of machine implementation, a naturally fuzzified system, such as a (complex) humanistic system, is more amenable to an initial test of the philosophy of pragmatic fuzzy subsets. Consequently, the fuzzy topology and spaces employed are intended to be devoid of extensive generalities, in this instance.     

几类增算子方程解的存在唯一性及应用

By using the cone theory and the monotone succession skills,it is studied the existence uniqueness of fixed point for a class of increasing operators without continuity and compactness and concave or convex conditions in Banach spaces.The results presented here improve and generalize some corresponding results for increasing operator.     

Modelling and analysis of dynamics of viral infection of cells and of interferon resistance

Interferons are active biomolecules, which help fight viral infections by spreading from infected to uninfected cells and activate effector molecules, which confer resistance from the virus on cells. We propose a new model of dynamics of viral infection, including endocytosis, cell death, production of interferon and development of resistance. The novel element is a specific biologically justified mechanism of interferon action, which results in dynamics different from other infection models. The model reflects conditions prevailing in liquid cultures (ideal mixing), and the absence of cells or virus influx from outside. The basic model is a nonlinear system of five ordinary differential equations. For this variant, it is possible to characterise global behaviour, using a conservation law. Analytic results are supplemented by computational studies. The second variant of the model includes age-of-infection structure of infected cells, which is described by a transport-type partial differential equation for infected cells. The conclusions are: (i) If virus mortality is included, the virus becomes eventually extinct and subpopulations of uninfected and resistant cells are established. (ii) If virus mortality is not included, the dynamics may lead to extinction of uninfected cells. (iii) Switching off the interferon defense results in a decrease of the sum total of uninfected and resistant cells. (iv) Infection-age structure of infected cells may result in stabilisation or destabilisation of the system, depending on detailed assumptions. Our work seems to constitute the first comprehensive mathematical analysis of the cell-virus-interferon system based on biologically plausible hypotheses.     

检修事件的概率分析与结构的维修可靠性

定期检修结构的可靠性分析,需要定量处理大量复杂的随机事件。综合考虑各种随机因素,较全面地分析了检修过程中影响可靠性的诸多复杂随机事件及其发生概率。系统地建立了检修结构的动态可靠性分析模型,整个模型程序化程度高,易于实施。     

投资与融资优化决策模型研究综述分析

本文对投资与融资优化模型及研究思路进行了分析,并对各类模型的改进或拓宽做了进一步讨论,为更深入研究组合投资和资本结构总体优化问题作准备。