整合供应商选择的多层级选址-库存模型

针对多级供应链网络设计中选址和库存一体化决策问题,基于梯级库存策略,建立了整合供应商选择的多层级选址-库存模型。模型以网络中供应商的选择成本、工厂和配送中心的打开成本、层级之间的运输成本、库存成本、采购成本和生产成本之和最小为目标,同时对供应商的选择、工厂和配送中心的选址、配送中心对顾客的分配、层级之间的运输量、工厂和配送中心的订货批量进行决策。为了求解所建立的模型,设计了基于部分编码的粒子群优化算法。20个不同规模的算例测试表明：所建立的模型是有效的,能用于多层级供应链网络的设计;所设计的算法无论是在求解精度,还是在运算速度上都明显优于数学优化软件Lingo 9.0,尤其是当供应链网络中总节点数较大时。     

随机时变需求下有阶段和总量约束的多源采购优化

针对有阶段采购量区间约束及最小总量要求的多供应商多阶段订单分配问题,以采购方采购、库存、缺货成本总和与期末库存残值之差的期望值最小为目标,建立随机非线性规划模型.考虑采购量约束及多供应商情形,扩展报童模型得出单阶段最优采购策略.以此为基础建立多阶段启发式算法,通过仿真分析各参数对最优采购策略及其总成本的影响.将最小总量承诺契约扩展到时变需求和多供应商情形,可为采购方降低成本.     

两级系统多周期随机库存路径优化

库存和运输是物流活动的最主要环节,如何同时对二者进行优化,是供应商管理库存必须解决的核心问题。针对一个配送中心为多个零售商实施统一配送的两级系统,以最小化系统计划期平均总费用为目标,分析包括零售商存储费、缺货费,以及配送中心进货费、存储费和配送费的系统全部费用组成,整合库存与配送建立了库存路径问题数学模型。根据零售商需求的随机性和库存路径问题本身的两阶段性,估计零售商库存上下限,选择配送中心订货策略及配送优先原则,借鉴旅行商问题求解思路,设计了求解问题的启发式算法。用Matlab7.0编程实现仿真算例求解表明,整合优化比分别优化节省平均总费用6.2%。     

随机需求下的供应链库存控制策略研究

考虑了由多个供应商、一个配送中心组成的二级供应链系统在市场需求为随机情况下的多品种库存问题。通过确定各变量之间的关系,以配送中心损失期望值最小为目标函数,建立了一个混合整数非线性规划模型;利用求解多元函数条件极值的办法来求解该问题模型;最后给出了一个算例进一步诠释了该解法,从而丰富了在面对市场为随即需求下的多品种库存控制策略的研究工作。     

JIT供应链物料采购协同优化及其粒子群算法

在供应链环境中,传统的物料需求计划没有考虑供应商的供货能力与经济利益,不利于供应链上下游企业的长期合作。研究了一种基于JIT的供应链物料采购协同优化问题,以单一制造商和多供应商构成的二级供应链为研究对象,遵循产品生产的BOM约束和MRP制定原理,以最小化供应链上下游企业的库存、运输、缺货、赶工等总成本为目标,构建了以MRP为引导的供应链订购批量协同优化模型;通过调整制造商的主生产计划变更采购计划,以获得供应商供货方案,据此设计了基于整数编码和带有交叉操作的改进离散粒子群优化算法进行模型求解;结合实例对模型可行性进行了验证,通过算法结果分析及比较,证明了算法的有效性。     

价格波动下钢铁企业原材料采购多期优化模型

考虑钢铁企业原材料需求、采购提前期及价格波动的影响,建立原材料采购的多期优化模型,最小化单位采购成本并保证原材料的供应。由于模型求解困难,将其分解为多个子模型,并采用改进的粒子群算法进行求解。最后以某钢铁企业铁矿石采购优化为案例,表明多期优化决策比单期最优经济采购决策和以补充库存为目的的采购策略更优。     

供应链中供应商选择决策方法

为了克服传统供应商选择过程中面向单一解的局限性,更好地解决供应链中供应商选择的多目标优化问题,达到费用和效益最佳,以产品价格、质量、交货可靠性和交货提前期为评估指标,建立了供应商选择多目标优化模型.首次将SPEA2算法应用于供应商选择问题,构造了适合该模型特征的SPEA2算法求解过程,可针对多个求解目标获得一组均衡解.模拟算例中一次得到多组有效解,表明所建立模型及所用方法是有效、可行的,它为制造企业获得有多种解决方案的供应商选择问题提供了可参考的模型和求解算法.     

顺天府超市的安全“隧道”

北京顺天府商贸有限公司创建于1994年,是北京地区最早创立的连锁超市公司之一。目前,在北京拥有18家直营店和1家配送中心,总营业面积20000余平方米,员工1300人。作为大型连锁超市,其经营中所涉及的信息是多方面的,超市本身已安装了超市信息管理系统,完整介入了连锁超市的整个管理,不仅采集数据,而且分析数据,为管理大规模的连锁超市提供了相当好的信息系统平台,可实现商品管理、卖场管理和供应商管理等操作。在这种庞大的信息系统的带动下,总部要及时掌握各分店公司的销售情况和配送中心的库存情况,子公司也要及时了解总部的调价信息、库存…     

基于双层规划的多供应商物料配送期量优化

为有效解决多供应商单制造商构成的二级供应链中供应商配送批量不经济、配送时间无序导致物流成本高和卸货拥堵等问题,建立多供应商配送期量的双层规划模型.上层模型从库存与配送联合优化视角,考虑供应商配送批量经济性,以供应链物流总成本最低为目标,确定最优配送批量;下层模型基于上层优化结果,考虑制造商生产时序性,以供应商时间惩罚成本最小化为目标,确定供应商配送时间序列.采用遗传算法和动态规划相结合的方法求解上下层模型,得到供应商最优配送期量标准.通过实例运用,验证了模型与算法的有效性及可行性.     

基于双层规划的多供应商物料配送期量优化

为有效解决多供应商单制造商构成的二级供应链中供应商配送批量不经济、配送时间无序导致物流成本高和卸货拥堵等问题,建立多供应商配送期量的双层规划模型.上层模型从库存与配送联合优化视角,考虑供应商配送批量经济性,以供应链物流总成本最低为目标,确定最优配送批量;下层模型基于上层优化结果,考虑制造商生产时序性,以供应商时间惩罚成本最小化为目标,确定供应商配送时间序列.采用遗传算法和动态规划相结合的方法求解上下层模型,得到供应商最优配送期量标准.通过实例运用,验证了模型与算法的有效性及可行性.     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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