A FRAMEWORK OF SETTING UP GOAL CONTROL LIMITS OF TARGET COSTING FOR NON-NORMAL DISTRIBUTIONS

This study provides a framework of target costing to extend its original scope when the underlying distribution is non-normal. The new specification limits can be derived by listening to the market price from Taguchi loss function. Later, the new specification limits can be linked through the non-normality-based C^^pk value along with non-normality-based X^^-Rcontrol charts to derive goal control limits. Moreover, an example is provided to illustrate the usefulness of the proposed framework of target costing by relentlessly reducing cost and improving product quality to gain competitiveness in the marketplace.     

AN IMPROVED MULTIVARIATE LOSS FUNCTION APPROACH TO OPTIMIZATION

The basic purpose of a quality loss function is to evaluate a loss to customers in a quantitativemanner.Although there are several multivariate loss functions that have been proposed and studied inthe literature,it has room for improvement.A good multivariate loss function should represent anappropriate compromise in terms of both process economics and the correlation structure amongvarious responses.More important,it should be easily understood and implemented in practice.According to this criterion,we first introduce a pragmatic dimensionless multivariate loss functionproposed by Artiles-Leon,then we improve the multivariate loss function in two respects:one ismaking it suitable for all three types of quality characteristics;the other is considering correlationstructure among the various responses,which makes the improved multivariate loss function moreadequate in the real world.On the bases of these,an example from industrial practice is provided tocompare our improved method with other methods,and la     

DESIGNING THE OPTIMUM CONFIGURATIONS OF CIRCULAR AND SPHERICAL PRODUCT SPECIFICATIONS FOR MULTIPLE QUALITY CHARACTERISTICS

1. Introduction The problem of determining an optimal tolerance is equivalent to the problem of determining optimal specification limits, since the term tolerance refers to the distance between its lower and upper specification limits. Functional performance and economic considerations are the two primary factors affecting the design of tolerances. A tighttolerance usually implies high manufacturing cost due to additional manufacturing operations, slow processing rates, additional care on part…     

A MARKOVIAN APPROACH TO DETERMINING PROCESS MEANS WITH DUAL QUALITY CHARACTERISTICS

This paper studies a production system where products are produced continuously and whose specification limits are specified for screening inspection. In this paper, we consider dual quality characteristics and different costs associated with each quality characteristic that falls below a lower specification limit or above an upper specification limit. Due to these different costs, the expected total profit will greatly depend on the process parameters, especially a process mean. This paper develops a Markovian-based model for determining the optimum process means with the consideration of dual quality characteristics in a single-stage system. The proposed model is then illustrated through a numerical example and sensitivity analysis is performed to validate the model. The results showed that the optimum process mean for both quality characteristics have a significant effect on the performance of the system. Since the literature survey shows that dealing with multi-quality characteristics is extremely limited, the proposed model, coupled with the Markovian approach, provides a unique contribution to this field.     

基于买方用户规范习惯的B2B电子中介IT投资决策

通过考虑IT成本下降、买方用户规范习惯及注意力成本等因素, 构建了序贯进入的、两寡头垄断的B2B电子中介IT投资决策模型, 探讨了IT成本下降、买方用户规范习惯及注意力成本等参数变化对B2B电子中介IT投资决策的影响. 研究结果表明, 随着IT成本下降, 当买方用户规范习惯水平较高时, 市场先入者可采取进攻性的、增加投资的策略; 反之, 当买方用户规范习惯水平较低时, 市场后入者则可采取进攻性的、增加投资的策略, 并且能够提供更高质量的网站, 有更高的市场需求; 随着网站信息量的增加, 先入者的买方用户注意力成本会增加, 后入者的买方用户注意力成本会减少, 随着注意力成本的这一变化趋势, 先入者和后入者可采取进攻性的、增加投资的策略. 研究结果可以为B2B电子中介的IT投资决策提供指导.     

动态投资目标下DC型养老基金的最优投资策略

本文考虑了基于动态投资目标下DC型养老基金在退休前累积阶段的最优资产配置问题。假定养老基金参与者根据其退休时的工资水平设置了一个预期的投资目标,并将其养老基金投资于由一个无风险资产和n个风险资产构成的金融市场.本文从赤字和净盈余两个角度出发分析养老基金账户值与参与者预期投资目标之间的的偏差,分别建立了基于平方损失和均值-方差目标准则之下的连续时间最优投资组合问题,然后获得了两个优化问题最优投资策略的解析形式,并分析了在上述两种最优策略之下期望终端财富之间的关系.最后通过数值算例进一步说明了本文结论。     

带转运中心的车辆组合运输问题的模型与算法

主要研究两类带有转运中心的车辆组合运输问题.一类是多期单产品的物流问题,一类是单期多产品的物流问题.建立了研究的两类物流系统的数学模型与算法,并通过算例对模型和算法进行了验证.主要应用动态规划方法、结合两阶段法与分支定界法的混合算法,使程序运行效率和解的满意性都得到很大提高.     

关于VAX/VMS上Fortran至Ada转换中几个技术问题

Ada语言是一种现代的模块化语言,它不仅是应用于工业控制、通讯和军事系统等实时领域的理想语言,还可以广泛地应用于系统程序设计、远程信息处理等各个领域。DEC公司VAX/VMS上实现的Ada就是非常高效的产品。由于工作需要,我们在VAX/VMS上将Ada引入控制系统,替代原来的Fortran程序。本文将阐述Fortran到Ada转换中的几个技术问题,这些技术问题的解决方法在我们的实验中证明是正确的。     

AN APPROACH TOWARDS THE IMPLEMENTATION OF CHARACTERISTIC SET METHOD

1.IntroductionInthiscentury,theinventionofcomputerhasbroughtustoanewrevolutionera:weevencouldnotimaginewhattheworldwouldlooklikewithoutcomputer.Nowadays,wehavegottenusedtolettingcomputerhelpustodoinformationsearching,wordprocessing,complicatedcomputationsandsoon.Buthowaboutthementalworkmechanization,i.e.askingcomputertodomelltalworkforussuchasreasoning?MathematicsmechanizationisanewresearchfieldinitiatedbyProfessorWuWentsUnll]taChinesemathematician.Itisanalgebraicapproachratherthanalogicapp…     

供应链产品质量检查策略的比较研究

研究由一个供应商和一个零售商组成的供应链,建立存在质量不确定与检查错误下的报童模型,比较分析全检、抽检、分批抽检以及组合策略在分散式与集中式供应链中对零售商订购决策与质量控制效率的影响.结果表明,次品率的增加会降低零售商订购产品的动因,但会增加组合策略下零售商的订购量与利润,同时对集中式供应链中全检策略下的零售商有利;比较策略可知,在分散式供应链中,若次品率较低,则分批抽检策略最优,而随着次品率的提高,组合策略会更优,而在集中式供应链中,全检策略最优;此外零售商质量控制策略的选择受到检查精度、责任成本、次品率阈值、抽检数量以及分批次数等诸多因素的影响,最优策略不尽相同,但不会改变零售商利润随次品率变化的趋势.     

复杂工业过程计算机建模、仿真与控制的综述

复杂工业过程控制是控制科学界的前沿。由于其背景的复杂性、控制对象的可变性 ,至今在实际工程甚至理论上尚未取得实质性进展。因此 ,在复杂环境和任务下的工业过程应当走逐步智能化的道路。在这一智能化进程中 ,试图从复杂工业过程计算机建模、仿真与控制三个方面来探讨其内在实质 ,找出其深层原因 ,同时指出其固有的局限性 ,以助于从事具体科学研究者自觉遵守认识的客观规律。     

一种基于遗传算法的最优空间布置方法

空间布置问题是工业生产中的瓶颈问题,因为存在太多的可能组合,容易陷入局部最小解。本文提出一种在空间布置问题中基于遗传算法把空间位置进行编码并通过遗传操作算子进行重定位和改变有限旋转方向策略的全局搜索方法。种群中每一个个体是一种有效的空间分配方案,在遗传算法进化过程中为减少计算时间,提高空间利用率,采用了多种启发式信息如原点策略、边策略、避免重复定位点策略和无悬挂策略等来加速收敛到全局最优解。最后,仿真例子说明了所提方法是工业应用中一种可选方案。     

模糊认知图与证据理论融合的质量控制决策模型

针对制造过程的质量问题层出不穷而企业常常疲于救火式管理、难以从根本上解决质量问题的现状,结合模糊认知图理论和证据理论,提出一种包含反应式、预防式、预报式和先行式等四种典型的质量控制模式的决策模型.论文首先分析这四种典型的质量控制模式及其决策因素;接着,讨论基于模糊认知图的质量控制决策模型及实施步骤,该模型立足于综合考虑质量问题属性、成本、功能符合性以及组织支持因素等维度,构建基于模糊认知图的决策网络.针对决策网络中多个专家所建立模糊认知图的合成问题,结合证据理论,以专家知识作为证据,节点间的因果强度的可能取值空间构成识别框架,对多个专家知识进行合成.最后,以某轴承企业深沟球轴承沟形误差超标的质量问题为例验证了该方法的可行性.     

正态分布下产品可靠性抽样检验方案——方差未知综合双侧情形

在综合双侧规格限下研究方差未知的正态分布产品可靠性抽样检验方法 .检验统计量取为不可靠度 p的极大似然估计 p.当 p小时 ,p的分布基本上仅依赖于 p ,对 p分解为下侧不可靠度和上侧不可靠度的依赖轻微 .因此 ,利用单侧规格限下的抽样检验方案近似地导出综合双侧规格限下的抽样检验方案 .随机模拟结果表明 ,给出的近似方法是有效的 ,抽样检验方案是合理的 .此外 ,检验统计量 p的表达式较简单.     

渠道权力结构与责任成本分担下供应链质量及协调研究

责任成本分担合同已被供应链企业广泛采纳以降低产品安全事故.基于此,构建了一个由制造商与零售商组成的供应链博弈模型,在三种渠道权力结构下,研究了责任成本分担对制造商产品质量决策等的影响,并考察了渠道权力结构对供应链均衡结果及契约协调的影响.结果表明:若制造商为领导者,则其责任成本分担的增加不影响其产品质量与供应链企业利润,反之,将促进其产品质量与供应链企业利润的增加;制造商为领导者时的产品质量可达到供应链系统最优;领导权力可使制造商获得较大利润,但对零售商不一定适用;制造商为领导者时可通过零售商收益分享与制造商转移支付实现协调,反之,可通过一个相同的由制造商收益分享与零售商质量成本分担、转移支付构成的组合契约实现协调.     

Supply chain coordination mechanisms under flexible contracts

In supply chain management, an important research direction is to coordinate the supply chain through introducing flexible contracts. A supply chain contract is flexible if it can satisfy two conditions at the same time: the supply chain is coordinated, and the total profit of the supply chain can be arbitrarily divided between the supply chain members. This paper puts out two contracts, a flexible return contract and a flexible wholesale price discount contract. In contrast to many of literature, the supply chain contracts with an endogenous wholesale price is specifically considered, and a detailed sensitivity analysis of the contract parameters is given. The paper also discusses the application of the contract in vendor-managed inventory (VMI) mode. The results show that the supply chain’s performance is improved after introducing above contracts. All the findings are illustrated by numerical examples.     

DESIGN SAMPLING AND REPLICATION ASSIGNMENT UNDER FIXED COMPUTING BUDGET

1. Introduction The essence of any decision problem is an optimization problem. Whether it is a decision on the production schedule of a manufacturing plant, a decision on the routing rules of networking, or a decision on the make-up of investment portfolios, the problem always revolves around making a choice from a population of alternatives (either finite or infinite) so as to optimize certain targeted objective. Without loss of generality, the objective can be represented by Mθ ∈iΘn J(…     

浅谈系统动力学理论在水产品冷链销售中的应 用简

以包装冻鳕鱼为例,引入产品质量损失成本概念,建立了水产品冷链销售的系统动力学模型。通过选取合适参数对模型进行仿真实验发现,冷链销售企业的利润水平随着水产品库存温度的降低而升高,随着库存覆盖时间的压缩而升高。运用系统论的功能主义观和整体观对仿真结果进行分析,认为水产品冷链销售企业乃至整个水产品供应链应该以产品质量为先,不仅有利于企业利润的增加,而且对于培育良好消费环境、推动水产品冷链物流整体运作水平、缓解食品安全问题具有重要作用。     

基于需求驱动的CSPS系统多目标优化控制

本文以最小化顾客流失率和最小化成品库平均在库数量为优化目标,研究基于需求驱动的传送带给料加工站(CSPS)系统的多目标优化问题.给出了前视距离控制和库存控制两种控制方式,并建立基于需求驱动的CSPS系统多目标优化模型.通过半马尔可夫决策过程长期平均性能公式计算目标值,然后使用NSGAⅡ和SPEA2两种多目标优化算法求解问题的最优策略集合.实验结果表明,加入库存控制方式可以在保证顾客需求的同时有效降低成品库平均在库数量.此外,针对模型特点,给出二进制-实数编码和连续化实数编码两种编码方式.通过验证,连续化实数编码可以有效提高算法的收敛性能及获得的非支配解集的质量.     

用于大工业过程建模的新型小波神经网络结构

提出一种新的小波神经网络结构 ,旨在解决输入变量比较多、变量分先后次序起作用的一类问题。该网络结构类似于多层前向神经网络 ,不同的是将一部分输入节点移至隐层 ,输入变量不是由同一层输入 ,而是根据变量起作用的前后次序分别在网络的不同层输入 ,从而使网络的规模减小 ;同时 ,隐层神经元的激励函数是一维小波函数 ,避免了多元小波函数带来的维数灾难问题。因此 ,该神经网络是处理高维问题的有效工具 ,尤其适用于包含多道加工工序的大工业过程的建模。将该神经网络用于热连轧产品质量建模 ,并经过了实测数据拟合与检验。试验结果表明 ,提出的小波神经网络结构是可行的 ,而且有很好的应用前景。