A multi-agent system architecture for coordination of just-in-time production and distribut
A Survey of Cyber-Physical Systems
A Survey of Cyber-Physical SystemsJiafu Wan a,ba School of Computer Science and EngineeringSouth China University of Technology,Guangzhou,Chinajiafuwan_76@Hehua Yan*,b,Hui Suo bb College of Information EngineeringGuangdong Jidian PolytechnicGuangzhou,China*Corresponding Author,hehua_yan@Abstract—Cyber Physical Systems(CPSs)are characterized by integrating computation and physical processes.The theories and applications of CPSs face the enormous challenges.The aim of this work is to provide a better understanding of this emerging multi-disciplinary methodology.First,the features of CPSs are described,and the research progresses are summarized from different perspectives such as energy control,secure control, transmission and management,control technique,system resource allocation,and model-based software design.Then three classic applications are given to show that the prospects of CPSs are engaging.Finally,the research challenges and some suggestions for future work are in brief outlined.Keywords-cyber physical systems(CPSs);communications; computation;controlI.I NTRODUCTIONCyber Physical Systems(CPSs)integrate the dynamics of the physical processes with those of the software and communication,providing abstractions and modeling,design, and analysis techniques for the integrated whole[1].The dynamics among computers,networking,and physical systems interact in ways that require fundamentally new design technologies.The technology depends on the multi-disciplines such as embedded systems,computers,communications,etc. and the software is embedded in devices whose principle mission is not computation alone,e.g.cars,medical devices, scientific instruments,and intelligent transportation systems[2]. Now the project for CPSs engages the related researchers very much.Since2006,the National Science Foundation(NSF)has awarded large amounts of funds to a research project for CPSs. Many universities and institutes(e.g.UCB,Vanderbilt, Memphis,Michigan,Notre Dame,Maryland,and General Motors Research and Development Center,etc.)join this research project[3,4].Besides these,the researchers from other countries have started to be aware of significance for CPSs research.In[5-7],the researchers are interested in this domain,including theoretical foundations,design and implementation,real-world applications,as well as education. As a whole,although the researchers have made some progress in modeling,control of energy and security,approach of software design,etc.the CPSs are just in an embryonic stage.The rest of this paper is outlined as follows.Section II introduces the features of CPSs.From different perspectives, the research processes are summarized in Section III.Section IV gives some classic applications.Section V outlines the research challenges and some suggestions for future work and Section VI concludes this paper.II.F EATURES OF CPS SGoals of CPSs research program are to deeply integrate physical and cyber design.The diagrammatic layout for CPSs is shown in Figure1.Obviously,CPSs are different from desktop computing,traditional embedded/real-time systems, today’s wireless sensor network(WSN),etc.and they have some defining characteristics as follows[7-10].∙Closely integrated.CPSs are the integrations of computation and physical processes.∙Cyber capability in every physical component and resource-constrained.The software is embedded inevery embedded system or physical component,andthe system resources such as computing,networkbandwidth,etc.are usually limited.∙Networked at multiple and extreme scales.CPSs,the networks of which include wired/wireless network,WLAN,Bluetooth,GSM,etc.are distributed systems.Moreover,the system scales and device categoriesappear to be highly varied.∙Complex at multiple temporal and spatial scales.In CPSs,the different component has probablyinequable Figure1.Diagrammatic layout for CPSsgranularity of time and spatiality,and CPSs are strictlyconstrained by spatiality and real time.∙Dynamically reorganizing/reconfiguring.CPSs as very complicated systems must have adaptive capabilities.∙High degrees of automation,control loops must close.CPSs are in favor of convenient man-machineinteraction,and the advanced feedback controltechnologies are widely applied to these systems.∙Operation must be dependable,certified in some cases.As a large scale/complicated system,the reliability andsecurity are necessary for CPSs.III.R EASEARCH P ROCESSSince2007,American government has treated CPSs as a new development strategy.Some researchers from various countries discussed the related concepts,technologies, applications and challenges during CPSweek and the international conference on CPS subject[11].The results of this research mainly concentrate in the following respects[7]. A.Energy ControlOne of the features of CPSs is distributed system.Though the vast majority of devices in CPSs need less energy,the energy supply is still a great challenge because the demand and supply of energy is inconvenient.In[12],a control strategy is proposed for realizing best trade-off between satisfying user requests and energy consumption in a data center.In[13-15],these papers concern the basic modeling of cyber-based physical energy systems.A novel cyber-based dynamic model is proposed in which a resulting mathematical model greatly depends on the cyber technologies supporting the physical system.F.M.Zhang et al [16]design optimal and adaptive discharge profile for a square wave impulsive current to achieve maximum battery life.J. Wei et al and C.J.Xue et al[17,18]develop an optimal lazy scheduler to manage services with minimum energy expenditure while not violating time-sensitive constraints.In [19],a peak inlet temperature minimization problem is formulated to improve the energy efficiency.J.R.Cao et al[20] present a clustering architecture in order to obtain good performance in energy efficiency.B.Secure ControlNow,the research for secure control mainly includes key management,identity authentication,etc.In[21],the existing security technologies for CPSs are summarized,and main challenges are proposed.C.Singh et al[22]explore the topic of the reliability assurance of CPSs and possibly stimulate more research in this area.T.T.Gamage et al[23]give a general theory of event compensation as an information flow security enforcement mechanism for CPSs.Then a case study is used to demonstrate this concept.In[24],a certifcateless signature scheme for mobile wireless CPSs is designed and validated.Y.Zhang et al[25]present an adaptive health monitoring and management system model that defines the fault diagnosis quality metrics and supports diagnosis requirement specifications.J.Wei et al[26]exploit message scheduling solutions to improve security quality of wireless networks for mission-critical cyber-physical applications.C.Transmission and ManagementCPSs need to conduct the transmission and management of multi-modal data generated by different sensor devices.In[27], a novel information-centric approach for timely,secure real-time data services in CPSs is proposed.In order to obtain the crucial data for optimal environment abstraction,L.H.Kong et al[28]study the spatio-temporal distribution of CPS nodes.H. Ahmadi et al[29]present an innovative congestion control mechanism for accurate estimation of spatio-temporal phenomena in wireless sensor networks performing monitoring applications.A dissertation on CPSs discusses the design, implementation,and evaluation of systems and algorithms that enable predictable and scalable real-time data services for CPS applications[30].Now,the exiting results are still rare,and there are many facets to be studied.D.Model-based Software DesignNow,the main model-based software design methods include Model Driven Development(MDD)(e.g.UML), Model-Integrated Computing(MIC),Domain-Specific Modeling(DSM),etc[31,32].An example,abstractions in the design flow for DSM,is shown in Figure2.These methods have been widely applied to the embedded system design[34, 35].On the basis of these,some researchers conduct model-based software design for CPSs in the following aspects:event model,physical model,reliability and real-time assurance,etc.Figure2.Abstractions in the design flow for DSM[33]1)Event model.E.A.Lee et al[36]make a case that the time is right to introduce temporal semantics into programming models for CPSs.A programming model called programming temporally-integrated distributed embedded systems(PTIDES) provides a coordination language rooted in discrete-event semantics,supported by a lightweight runtime framework and tools for verifying concurrent software components.In[37],a concept lattice-based event model for CPSs is proposed.This model not only captures the essential information about events in a distributed and heterogeneous environment,but it alsoPlatform mapping Abstractions are linkedthrough refinementrelationsAbstraction layers allowthe verification ofdifferent propertiesPlatform mappingAbstraction layersdefine platformsallows events to be composed across different boundaries of different components and devices within and among both cyber and physical domains.In addition,A CPS architecture along with a novel event model for CPS is developed[38].2)Physical model.In[39],a methodology for automatically abstracting models of CPSs is proposed.The models are described using a user-defined language inspired by assembly code.For mechanical systems,Y.Zhu et al[40]show how analytical models of a particular class of physical systems can be automatically mapped to executable simulation codes.S.Jha et al[41]present a new approach to assist designers by synthesizing the switching logic,given a partial system model, using a combination of fixpoint computation,numerical simulation,and machine learning.This technique quickly generates intuitive system models.3)Reliability and real-time assurance. E. A.Lee[42] emphasizes the importance of security,reliability and real-time assurance in CPSs,and considers the effective orchestration of software and physical processes requires semantic models. From the perspective of soft real-time and hard real-time,U. Kremer[43]conducts the research that the role of time in CPS applications has a fundamental impact on the design and requirements.In CPSs,the heterogeneity causes major challenges for compositional design of large-scale systems including fundamental problems caused by network uncertainties,such as time-varying delay,jitter,data rate limitations,packet loss and others.To address these implementation uncertainties,X.Koutsoukos et al[44]propose a passive control architecture.For improving reliability,T.L. Crenshaw et al[45]describe a simplex reference model to assist developers with CPS architectures which limit fault-propagation.A highly configurable and reusable middleware framework for real-time hybrid testing is provided in[46].Though the model-based software design has an early start, the present development of CPSs progresses at a fast enough rate to provide a competitive challenge.E.Control TechniqueCompared with other control applications,the control technique for CPSs is still at an elementary stage.F.M.Zhang et al[2]develop theoretical results in designing scheduling algorithms for control applications of CPS to achieve balances among robustness,schedulability and power consumption. Moreover,an inverted pendulum as a study object is designed to validate the proposed theory.N.Kottenstette et al[47] describe a general technique:passivity and a particular controller structure involving the resilient power junction.In [48],a design and implementation of CPSs for neutrally controlled artificial legs is proposed.In[49],J.L.Ny et al approach the problem of certifying a digital controller implementation from an input-output,robust control perspective.F.System Resource AllocationUntil now,the relative research for system resource allocation mainly focuses on embedded/real-time systems, networked control systems,WSN,etc[50-52].Towards the complicated CPSs,this work is in the beginning stage.V.Liberatore[53]gives a new train of thought on bandwidth allocation in CPSs.In[54],the model dynamics are presented to express the properties of both software and hardware of CPSs,which is used to do resource allocation.K.W.Li et al [55]research the problem of designing a distributed algorithm for joint optimal congestion control and channel assignment in the multi-radio multi-channel networks for CPSs.The ductility metric is developed to characterize the overload behavior of mixed-criticality CPSs in[56].IV.C LASSIC A PPLICATIONSApplications of CPSs include medical devices and systems, assisted living,traffic control and safety,advanced automotive systems,process control,energy conservation,environmental control avionics and aviation software,instrumentation,critical infrastructure(e.g.power,water),distributed robotics,weapons systems,manufacturing,distributed sensing command and control,smart structures,biosystems,communications systems, etc.[9,10].The classic application architecture of CPSs is described in[38].Now,some application cases for CPSs have been conducted in[57-64].Here,three examples(Health Care and Medicine,Intelligent Road and Unmanned Vehicle,and Electric Power Grid)are used to illuminate the classic applications of CPSs[8,9].A.Health Care and MedicineThe domain of health care and medicine includes national health information network,electronic patient record initiative, home care,operating room,etc.some of which are increasingly controlled by computer systems with hardware and software components,and are real-time systems with safety and timing requirements.A case of CPSs,an operating room,is shown in Figure3.Figure3.A case of CPSs:An operating room[8,9]B.Electric Power GridThe power electronics,power grid,and embedded control software form a CPS,whose design is heavily influenced by fault tolerance,security,decentralized control,and economic/ ethical social aspects[65].In[8,9],a case of CPSs,electric power grid,is given as shown in Figure4.Figure4.A case of CPSs:Electric power grid[8,9]C.Integrate Intelligent Road with Unmanned VehicleWith the development of sensor network,embedded systems,etc.some new solutions can be applied to unmanned vehicle.We are conducting a program that intelligent road and unmanned vehicle are integrated in the form of CPSs.Figure5 shows another case of CPSs:Integrate intelligent road with unmanned vehicle.Figure5.A case of CPSs:Integrate intelligent road with unmanned vehicleV.R ESEARCH C HALLENGESCPSs as a very active research field,a variety of questions need to be solved,at different layers of the architecture and from different aspects of systems design,to trigger and to ease the integration of the physical and cyber worlds[66].In[10, 42,66-68],the research challenges are mainly summarized as follows:1)Control and hybrid systems.A new mathematical theory must merge event-based systems with time-based systems for feedback control.This theory also must be suitable for hierarchies involving asynchronous dynamics at different time scales and geographic scope.2)Sensor and mobile networks.In practical applications, the need for increased system autonomy requires self-organizing/reorganizing mobile networks for CPSs.Gathering and refining critical information from the vast amount of raw data is essential.3)Robustness,reliability,safety,and security.It is a critical challenge because uncertainty in the environment,security attacks,and errors in physical devices make ensuring overall system robustness,security,and safety.Exploiting the physical nature of CPS by leveraging location-based,time-based and tag-based mechanisms is to realize security solutions.4)Abstractions.This aspect includes real-time embedded systems abstractions and computational abstractions,which needs new resource allocation scheme to ensure that fault tolerance,scalability,optimization,etc.are achieved.New distributed real-time computing and real-time group communication methods are needed.In addition,the physical properties also should be captured by programming abstractions.5)Model-based development.Though there several existing model-based development methods,they are far from meeting demands in puting and communications,and physical dynamics must be abstracted and modeled at different levels of scale,locality,and time granularity.6)Verification,validation,and certification.The interaction between formal methods and testing needs to be established. We should apply the heterogeneous nature of CPS models to compositional verification and testing methods.VI.C ONCLUSIONSIn the last few years,this emerging domain for CPSs has been attracting the significant interest,and will continue for the years to come.In spite of rapid evolution,we are still facing new difficulties and severe challenges.In this literature, we concisely review the existing research results that involve energy control,secure control,model-based software design transmission and management,control technique,etc.On this basis,some classic applications used to show the good prospects.Then,we propose several research issues and encourage more insight into this new field.A CKNOWLEDGMENTThe authors would like to thank the National Natural Science Foundation of China(No.50875090,50905063), National863Project(No.2009AA4Z111),Key Science and Technology Program of Guangdong Province(No. 2010B010700015),China Postdoctoral Science Foundation (No.20090460769)and Open Foundation of Guangdong Key Laboratoryof Modern Manufacturing Technology(No. GAMTK201002)for their support in this research.R EFERENCES[1]Available at:/cps/.[2] F.M.Zhang,K.Szwaykowska,W.Wolf,and V.Mooney,“Taskscheduling for control oriented requirements for Cyber-Physical Systems,”in Proc.of2008Real-Time Systems Symposium,2005,pp.47-56.[3]Available at:/news/17248-nsf-funds-cyber-physical-systems-project/.[4]J.Sprinkle,U.Arizona,and S.S.Sastry,“CHESS:Building a Cyber-Physical Agenda on solid foundations,”Presentation Report,Apr2008.[5]Available at:/.[6]Available at:/gdcps.html.[7]J.Z.Li,H.Gao,and B.Yu,“Concepts,features,challenges,andresearch progresses of CPSs,”Development Report of China Computer Science in2009,pp.1-17.[8]R.Rajkumar,“CPS briefing,”Carnegie Mellon University,May2007.[9] B.H.Krogh,“Cyber Physical Systems:the need for new models anddesign paradigms,”Presentation Report,Carnegie Mellon University. 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4-PRP_aR并联机构尺度参数多目标优化
设 BiCi 与 zi 轴负向的夹角为 θi。在{mi}中，沿 Pai3 副中心线 BiCi方向的单位矢量为（cos θi，0，−sin θ）i T， 其 内 部 4 个 转 动 副 轴 线 方 向 的 单 位 矢 量 为（0， 1，
（3 重庆工商大学 制造装备机构设计与控制重庆市重点实验室， 重庆 400067）
摘要 以三移动一转动 4-PRPaR 并联机构为研究对象，采用进化多目标算法求解机构尺度综合 问题。应用约束旋量理论分析机构自由度，给出了机构位置逆解解析表达式，为机构性能分析奠定 基础。建立机构运动和力传递性能评价指标，给出了规则有效传递工作空间（Regular effective trans⁃ mission workspace，RETW）及其平均传递指标的定义。以最大化 RETW 半径及平均传递指标为目标， 建立机构尺度参数多目标优化设计模型，并应用快速精英多目标遗传算法和差分进化算法相结合的 方法求解该问题。给出了机构尺度参数多目标优化设计实例。结果表明，模型和算法可行有效，可 为物理样机研制和实际应用提供理论基础。
Deb 等[10]182-197 设 计 的 第 2 代 非 支 配 排 序 遗 传 算 法（Nondominated sorting genetic algorithm Ⅱ，NSGAⅡ）是当前最流行的进化多目标算法之一，具有运行 速度快和收敛性好等优点。该算法的主要特点是： 用快速非支配排序方法来降低计算复杂度，用精英 保留策略来避免丢失最优解和提高收敛速度，用拥 挤距离计算来增大最优解的分布广度。Wu 等[11-12]研 究了一种 3T1RZ 型并联机构 Ragnar 的尺度参数多目 标优化问题，以最大化规则工作空间、全域传递指 标为目标，应用 NSGA-Ⅱ求解该双目标优化问题， 得到多组 Pareto 备选解。Brinker 等[13]针对 Delta 机器 人尺度参数多目标优化设计问题，以最大化传递 指标、工作空间与可达空间的比值为目标，采用 NSGA-Ⅱ求解 3 目标优化问题，得到多组备选解。
雅思真题剑八Test 1 reading 1--a chronicle of timekeeping
2. As the Roman Empire expanded northward, it orgranised its activity chart for the most part around the solar year. 语法点：时间状语从句 参考译文：随着罗马帝国向北扩张，它的活 动图表通常都是根据回归年而编排的。
3. at least 至少 反义词：at most There were at most twenty people in the classroom. 教室里最多不过20人。 4. coordinate vt.调节，协调，配合 The agencies are working together to coordinate policy on food safety. 派：名词 coordination coordinator 协调 者 形容词 coordinative 5. communal activities 社区活动 6. in particular 特别，尤其
3. annual adj.每年的, 年度的 an ~ income年收入 4. span n.时期, 跨度, 间距 vt.延续, 横跨, 贯穿, 遍及, 弥补 5. the ~ of life 人的一生 = lifespan 寿命 = life circle the ~ of a bridge桥的全 长 His professional career spanned 16 years. 他的职业生涯持续了 16 年。 Many bridges span the Thames. 很多桥横 亘在泰晤士河上。
7. regulate vt. 管理,规定; 限制,管理; 整顿; 管制 = manage，govern 派：名词regulation 规则，规章 = rule 8. base on 基于，以…为基础 • 9. successive adj. 连续的，相继的 同 义词：continuous • The team has had five successive victories. 球队已经取得5次连续的胜利。 • Successive governments have tried to deal with this issue. 历届政府都试图解决 这个问题。
唐讴
唐讴，博士，副教授，同济大学EMBA项目兼职教授唐讴于2000获得瑞典Link?ping 大学生产经济学博士学位，目前是Link?ping 大学的副教授，同时是Institute for Operations Research and the Management Sciences (INFORMS), Production and Operations Management Society (POMS), International Society for Inventory Research (ISIR)的成员和 Sloan Industry Studies Affiliates (USA)的特邀成员。
已发表70篇科学论文，其中包括24篇发表在European Journal of Operational Research, International Journal of Production Research, International Journal of Production Economics, Economic Systems Research, Production and Operations Management, OMEGA等期刊上。
在2003-2004和2006-2008年期间任International Journal of Production Economics期刊的客座编辑。
主要的研究领域在于供应链管理（重点是生产和库存建模）、计划和控制系统、逆向物流、全球供应链和风险管理。
简历：2005-2007：Tekes, Nokia and TeliaSonera：The dynamics of value creation in ICT value network，Key researcher。
2004- present：Brescia University：Consignment stock and its application in industry，Principle investigator。
基于adams的小车式起落架着陆及全机滑跑动态仿真
ii
基于 ADAMS 的小车式起落架着陆及全机滑跑动态仿真
图清单
图 2.1 多体系统动力学建模与求解一般过程 .....................................................8 图 2.2 ADAMS 软件求解方法及过程....................................................................... 11 图 2.3 飞机数字功能样机组成 ...........................................................................14 图 3.1 小车式起落架的结构 ...............................................................................16 图 3.2 小车式起落架结构模型 ...........................................................................18 图 3.3 外筒受力图 ...............................................................................................18 图 3.4 内筒受力图 ...............................................................................................19 图 3.5 车架受力图 ...............................................................................................20 图 3.6 后轮受力图 ...............................................................................................20 图 3.7 前轮受力模型 ...........................................................................................21 图 3.8 缓冲器结构模型 .......................................................................................22 图 3.9 缓冲器受力图 ...........................................................................................24 图 3.10 圆角方形截面结构 .................................................................................25 图 4.1 起落架 CATIA 三维建模..........................................................................29 图 4.2 设计过程 Step 函数结果曲线 ..................................................................31 图 4.3 IMPACT 函数示意图.................................................................................32 图 4.4 ADAMS 仿真模型 .....................................................................................32 图 4.5 缓冲器随行程变化曲线 ...........................................................................35 图 4.6 空气弹簧力随行程变化曲线 ...................................................................35 图 4.7 油液阻尼力随行程变化曲线 ...................................................................35 图 4.8 缓冲器的功量图 .......................................................................................36 图 4.9 轮胎作用力 ...............................................................................................36 图 4.10 后轮冲击载荷 .........................................................................................37 图 4.11 前轮冲击载荷..........................................................................................37 图 4.12 缓冲器行程变化曲线 .............................................................................38 图 4.13 不同重量下的缓冲器行程 .....................................................................39 图 4.14 不同重量下起落架对机身的冲击载荷 .................................................39 图 4.15 空气弹簧力随行程变化的比较曲线 .....................................................40 图 4.16 缓冲器的功量图 .....................................................................................41 图 5.1 理想的变油孔面积曲线形式 ...................................................................46
时滞变质品供应链的数量折扣协调模型
运 筹 与 管 理
ＯＰＥＲＡＴＩＯＮＳＲＥＳＥＡＲＣＨ ＡＮＤＭＡＮＡＧＥＭＥＮＴＳＣＩＥＮＣＥ
Ｖｏｌ．２９，Ｎｏ．３ Ｍａｒ．２０２０
时滞变质品供应链的数量折扣协调模型
张云丰， 龚本刚， 桂云苗
（安徽工程大学 管理工程学院，安徽 芜湖 ２４１０００）
Ａ ＣｏｏｒｄｉｎａｔｉｏｎＭｏｄｅｌｆｏｒＳｕｐｐｌｙＣｈａｉｎｏｆＮｏｎｉｎｓｔａｎｔａｎｅｏｕｓ ＤｅｔｅｒｉｏｒａｔｉｎｇＩｔｅｍ ＢａｓｅｄｏｎＱｕａｎｔｉｔｙＤｉｓｃｏｕｎｔＣｏｎｔｒａｃｔ
ＺＨＡＮＧ Ｙｕｎｆｅｎｇ，ＧＯＮＧ Ｂｅｎｇａｎｇ，ＧＵＩＹｕｎｍｉａｏ （ＳｃｈｏｏｌｏｆＭａｎａｇｅｍｅｎｔＥｎｇｉｎｅｅｒｉｎｇ，ＡｎｈｕｉＰｏｌｙｔｅｃｈｎｉｃＵｎｉｖｅｒｓｉｔｙ，Ａｎｈｕｉ，Ｗｕｈｕ，２４１０００）
摘 要：在由单个批发商与单个零售商组成的两级时 滞 变 质 品 供 应 链 中，分 别 建 立 分 散 决 策 和 集 中 决 策 下 供 应 链 系统的单位时间利润函数，通过比较得到集中决策优于分散决策的条件。引入数 量 折 扣 契 约 对 时 滞 变 质 品 供 应 链 进行协调，促使整个供应链系统实现集中决策下的 最 优 状 态。 设 计 收 益 共 享 合 同 来 合 理 分 配 协 调 后 的 利 润 增 量， 保证批发商和零售商的单位时间利润都比协调前 有 所 增 加，从 而 实 现 供 应 链 系 统 的 帕 累 托 改 善。 最 后，通 过 数 值 算例演示了两种决策模式的单位时间利润情况，并分析了关键参数对供应链系统及 各 成 员 企 业 单 位 时 间 利 润 水 平 的影响。 关 键 词 ：供 应 链 协 调 ；时 滞 变 质 品 ；数 量 折 扣 ；时 滞 期 ；变 质 率 中 图 分 类 号 ：Ｆ２５３．２ 文 章 标 识 码 ：Ａ 文 章 编 号 ：１００７３２２１（２０２０）０３００９９０８ ｄｏｉ：１０．１２００５／ｏｒｍｓ．２０２０．００６７
基于Kriging模型的自适应多阶段并行代理优化算法
第27卷第11期2021年11月计算机集成制造系统Vol.27No.11 Computer Integrated Manufacturing Systems Nov.2021DOI：10.13196/j.cims.2021.11.016基于Kriging模型的自适应多阶段并行代理优化算法乐春宇，马义中+(南京理工大学经济管理学院，江苏南京210094)摘要：为了充分利用计算资源，减少迭代次数,提出一种可以批量加点的代理优化算法。
该算法分别采用期望改进准则和WB2(Watson and Barnes)准则探索存在的最优解并开发已存在最优解的区域,利用可行性概率和多目标优化框架刻画约束边界。
在探索和开发阶段，设计了两种对应的多点填充算法，并根据新样本点和已知样本点的距离关系，设计了两个阶段的自适应切换策略。
通过3个不同类型算例和一个工程实例验证算法性能，结果表明，该算法收敛更快，其结果具有较好的精确性和稳健性。
关键词:Kriging模型;代理优化;加点准则；可行性概率;多点填充中图分类号：O212.6文献标识码：AParallel surrogate-based optimization algorithm based on Kriging model usingadaptive multi-phases strategyYUE Chunyu,MA Yizhong+(School o£Economics and Management,Nanjing University of Science and Technology,Nanjing210094,China) Abstract：To make full use of computing resources and reduce the number of iterations,a surrogate-based optimization algorithm which could add batch points was proposed.To explore the optimum solution and to exploit its area, the expected improvement and the WB2criterion were used correspondingly.The constraint boundary was characterized by using the probability of feasibility and the multi-objective optimization framework.Two corresponding multi-points infilling algorithms were designed in the exploration and exploitation phases and an adaptive switching strategy for this two phases was designed according to the distance between new sample points and known sample points.The performance of the algorithm was verified by three different types of numerical and one engineering benchmarks.The results showed that the proposed algorithm was more efficient in convergence and the solution was more precise and robust.Keywords:Kriging model；surrogate-based optimization；infill sampling criteria；probabil让y of feasibility；multipoints infill0引言现代工程优化设计中，常采用高精度仿真模型获取数据，如有限元分析和流体动力学等E,如何在优化过程中尽可能少地调用高精度仿真模型，以提高优化效率，显得尤为重要。
基于模糊时间窗的多中心开放式车辆路径问题
基于模糊时间窗的多中心开放式车辆路径问题杨翔;范厚明;张晓楠;李阳【摘要】针对受时间窗影响的多中心开放式车辆路径问题,采用时间窗模糊化处理方法,假设时间窗是一个梯形模糊数,定义客户满意度函数和时间惩罚费用函数,建立有鲁棒优化模型.基于整体法假设虚拟配送中心,设计改进的蚊群算法求解,选取合适的测试算例实验.实验结果表明,所提算法能获得较好的解,是求解该类问题的有效方法;所建模型满足问题的多中心、多需求点和开放式特征,模型合理有效;与软时间窗和硬时间窗设置相比,模糊时间窗设置合理有效,同时展示了模糊时间窗设置下客户满意度对模型求解结果的影响.【期刊名称】《计算机集成制造系统》【年(卷),期】2016(022)007【总页数】11页(P1768-1778)【关键词】车辆路径问题;多中心车辆路径问题;开放式车辆路径问题;模糊时间窗;蚁群算法【作者】杨翔;范厚明;张晓楠;李阳【作者单位】大连海事大学交通运输管理学院,辽宁大连116026;大连海事大学交通运输管理学院,辽宁大连116026;大连海事大学战略管理与系统规划研究所,辽宁大连116026;陕西科技大学机电工程学院,陕西西安710021;大连海事大学交通运输管理学院,辽宁大连116026【正文语种】中文【中图分类】TP301车辆路径问题(Vehicle Routing Problem, VRP)一直是供应链管理和物流系统规划的关键难题[1]。
随着对VRP研究的深入和拓展，多中心VRP(Multi-Deport VRP, MDVRP)和开放VRP(Open VRP, OVRP)开始受到关注。
MDVRP与经典VRP的主要区别是系统中有多个配送中心，车辆从某一配送中心出发服务客户，学者Bell采用蚁群算法求解单中心VRP，讨论了解决MDVRP的设想，指出当单配送中心问题扩展到多配送中心时，其解决思路和求解变得更加复杂[2];David等给出了求解单中心VRP的启发式算法，并将其应用于求解复杂的MDVRP[3];Filipec等设计了遗传算法对MDVRP进行求解，提出启发式改进策略[4];戴树贵等采用混合蚁群算法求解，改进了蚁群转移策略和可行解构造方法[5]。
一种基于多Agent 适配器的构件重用方法（英文）
一种基于多Agent 适配器的构件重用方法（英文）迟忠先;阿不都·克里木;高永强;王忠【期刊名称】《大连理工大学学报》【年(卷),期】2002(042)001【摘要】首先提出一种构件适应方法--通过为构件外挂适配器--来解决构件重用中的"接口匹配、消息处理、状态监控和环境模拟"等问题. 并采用多Agent适配器来建立一个可适应机制. 然后讨论基于这种多Agent适配器的构件适应技术的体系结构和建模方法. 最后给出该方法的应用实例和相关的工作.%This paper first presents a component adaptation method-assemble, which can solve the problems of interface matching, message handling, state monitoring, environment simulation and adopts multiagent adapter to build a flexible mechanism. Then a component reuse architecture based on this method is discussed. In the final section, related work and summary are given.【总页数】6页(P104-109)【作者】迟忠先;阿不都·克里木;高永强;王忠【作者单位】大连理工大学,计算机科学系,辽宁,大连,116024;大连理工大学,计算机科学系,辽宁,大连,116024;大连理工大学,计算机科学系,辽宁,大连,116024;大连理工大学,计算机科学系,辽宁,大连,116024【正文语种】中文【中图分类】TP311【相关文献】1.一种基于移动Agent的软件构件动态适配方法 [J], 赵文明2.一种基于适配器的构件组合方法 [J], 姜宇;苏中滨;黄芳3.一种基于构件库的构件重用支撑系统CRSS [J], 方潜生;张文祥4.一种基于多Agent的Internet上JavaBean构件挖掘方法 [J], 王斌;王建新;张尧学;陈松乔5.一种基于多Agent适配器的组合软件建模方法 [J], 迟忠先;权小蕊;王晨光;王忠因版权原因，仅展示原文概要，查看原文内容请购买。
Epicor-Supply-Chain-Management-BR-ENS-0310
Business without BarriersSupply ChainManagementSupply Chain ManagementSales ManagementCustomer RelationshipManagementService ManagementHuman Capital ManagementProduct Data ManagementProject ManagementFinancial ManagementProduction ManagementPlanning and SchedulingBusiness without barriers means effectively connecting your supply chain, enabling productive customer and supplier collaboration, and perfectly fulfilling demand.Linking the trading partners, processes, and systems that make up your supply chain has become the differentiation you need to achieve industry-leading performance. Removing processes that do not add value and synchronizing processes within and outside a company enable you to meet customer demands for lower cost and faster delivery. Epicor provides the most effective coordination from initial raw materials to the ultimate consumption of the finished product by providing the visibility you need throughout your value chain.Epicor offers you a full range of Supply Chain Management (SCM) capabilities, built within a single business platform, based on industry leading service-oriented architecture (SOA). Epicor SCM is a full suite of enterprise application capabilities including purchase management, sourcing and procurement, inventory management, advanced material management, and warehouse management, and is complemented by order and demand management capabilities of Epicor Sales Management. Combined, you have the solution needed to satisfy customers and customer demand in today’s increasingly global market place.Purchase ManagementPurchase Management handles purchase order writing and the tracking of supplier performance. Detailed line itemsindicate planned receipts to inventory or a job, although their destination may be changed at the time of actual receipt entry. Purchase order receipt processing updates suggested supplier and detailed purchase history files, which provides continual reference to aid in making purchasing decisions. With Purchase Management, you can reduce inventory levels, improve on-time deliveries, enhance your cash flow, and increase your profit levels.Approved SuppliersApprove suppliers before anything can be ordered from them. To accommodate customers that insist upon using specific suppliers, Epicor allows you to define those relationships, and prevents ordering from the wrong supplier for those jobs.Automated Purchasing ToolsAutomate part suggestions, quantities, and suppliers to buy from in order to meet material requirements and on-time delivery schedules. Optionally create new POs automatically.Cross-ReferencingWhen a supplier’s part number differs from the stocking part number, link the cross-reference in the suggested supplier file for printing on purchase orders.Mass Purchase Order ReceiptQuickly create receipt details for all lines, all releases for a specific line, or individual lines and releases.Multiple Location ReceiptsReceive individual lines or line releases to different locations for multi-site organizations with centralized buyers.Part Master Price BreaksCreate price breaks, including effectivity date per inventory part or supplier.Purchase RequisitionRequest purchases from anywhere in the plant. A formal requisition system tracks the status of the requisition, from initial request to final approval and actual purchase order. The requestor is notified each step of the way.Enter, approve, and confirm purchase orders with multiple line items and releases.Epicor SupplyChain ManagementPurchase HistoryAccess detailed information on purchase orders and receipts over extended periods of time from purchase history. Purchase Order PrintingPrint purchase orders directly from PO entry by date, user or purchase order number range. Purchase orders also may be faxed directly from your computer to your supplier.Purchase Order TrackerImmediately access all purchase order information via screen inquiry, with multiple search capabilities.Supplier TrackerQuickly display information about any supplier, including open and historical purchasing transactions.Supplier Portal Content PackLeveraging the capabilities of Epicor Portal, the Supplier Portal Pack improves business efficiency by extending traditional boundaries for doing business with suppliers. Epicor Portal Supplier Content Pack provides interactive supplier facing content that supports strategic goals for improved supplier communication and direct collaboration on day-to-day business, right from your Web site. Suppliers enjoy 24x7self service and can access, review, and approve purchase orders and changes and submit pricing in response to request for quotes (RFQs).Purchase ContractsEpicor Purchase Contracts is useful for purchasing inventory items on a recurring basis. You can establish delivery schedules that are regularly re-issued, against which recurring deliveries are made.The advantage of this functionality is ease and accuracy. For example, if you need a quantity of Part ABC to be purchased monthly, you need not enter a discrete purchase order each month. Rather, you can set up a contract PO schedule and maintain this record.Contract line items can be assigned to purchase orders. These line items automate delivery schedules, with delivery dates, prices, and corresponding quantities.Requirements determined by Generate PO Suggestions are calculated and realized into delivery schedules. The schedules can be adjusted manually in order to conform to supplier requirements, inventory control, production efficiency, and business expediency.Part ScheduleUse Part Schedule Maintenance to establish the combination of part, plant, and calendar that makes up the part schedule. This program is useful for assigning a period of frequency and minimum quantity for a part schedule.Periodicity CodeUse Periodicity Code Maintenance to establish the rules and terms under which orders periodically arrive from suppliers. Sourcing and ProcurementStrategic sourcing is the most important, value-added activity that procurement professionals perform for their company. Doing it well requires a wide range of skills and subject matter expertise.Sourcing by “old school“ methods requires an inordinate amount of time gathering and comparing offerings from multiple suppliers. Automating those tasks with Epicor Sourcing not only allows the purchasing professional to focus more time and energy on strategic activities, it also provides for online collaboration and fosters competition that amplifies the value of their work.Configurable SourcingEpicor Sourcing is a highly configurable, Web-based framework that extends Epicor Supplier Relationship Management capabilities to provide companies the flexibility to quickly and easily integrate strategic sourcing, dynamic pricing, collaboration and negotiation, and complex auctioning capabilities.Automated Electronic RequestsWhether buying, selling, or sourcing direct and indirect materials, goods, services, or spot purchases, everythingyou need is here. Epicor Sourcing automates requests for information, quotes, or proposals, accelerating the process and helping negotiate the best value. Buyers evaluate suppliers on price and non-price parameters with weighted attribute RFx. Streamlining the manual RFx process allows buyers to evaluate and select suppliers based on value to the organization.Weighted AttributesWeighted attributes enable buyers to establish any numberof attributes on which to gather and compare values from bidders. These fully configurable attributes allow for relative weighting of each attribute and associated response value. The complex algorithms required for quantitative scoring of responses are all handled by Sourcing.Side-by-side ComparisonSide-by-side comparisons of responses from multiple bidders make it easy for buyers to evaluate them and select a winner. The event scoreboard enables the buyer to make “split“ awards and optimize the award based on lower total costs and not just the best bid. This time-saving element promotes quicker, better-informed decisions.Graphical Bid AnalysisEpicor Sourcing provides graphical bid analysis. Bids from all participants are graphed in a dynamic, real-time display, giving the buyer a visual picture of an event’s progress and success.Organizations can define and maintain metrics of supplier performance. Supplier report cards help drive purchasing decisions and evaluate suppliers. Report cards are configurable based on user-defined parameters such as quality, responsiveness, delivery, and cost. Each parameter can then be weighted and scored.True Online CollaborationEpicor Sourcing enables true online collaboration and negotiation with suppliers. With the solution, you can facilitate event creation and automate true cross-enterprise workflow. Information is disseminated throughout the organization and allows online negotiation between buyers and suppliers. Supplier Relationship ManagementSupplier Relationship Management (SRM) provides tools for buyers, procurement staff and purchasing agents, or those providing quotes, to request quotes for raw materials or subcontract services from one or multiple suppliers. RFQs are generated with one or more lines, each line having the ability to request pricing from one or more suppliers.Supplier RFQ responses automatically build or add to existing part price-break tables, with current effectivity dates to be used in other Epicor applications.Buyer’s WorkbenchManage all associated purchasing transactions including request for quote, order expediting, purchase order management, and supplier account management, as well as drill down to all associated information.Part Price-Break TablesSupplier RFQ responses automatically build part price-break tables for use with other applications.RFQ Decision WizardFilter and sort RFQ criteria based on your specific needs tofind the best match for the needed materials. Sort criteria include lead-time, price, quality rating, ISO certification, and on-hand inventory.Inventory ManagementInventory Management provides the key functions necessary to update and maintain raw materials, WIP, and finished goods inventory quantities and costs. MRP creates inventory allocations for jobs entered through Job Management or generated from Order Management. These allocations are relieved as inventory items are issued to the job, or as purchase order receipts are posted.Issued inventory reduces quantities on hand, which are continually replenished through the processing of purchased or manufactured item receipts into inventory. Receipt processing provides a continual update of inventory average, FIFO, lot or last costs for every item. A variety of screen inquiries provide management analysis of MRP, shortage monitoring, reorder analysis, stock status, valuation, and critical items.Alternate PartsSetup in part maintenance as alternate parts you have the ability to define these alternates as either complimentary or as substitutes and these are made available in the various order entry processes. Complimentary indicates other items that “go with“ the part being ordered as a suggestion of other items they might consider. With substitutes (where you don’t have stock of the requested part) there are three types; Comparable, Downgrade or Upgrade and as the naming indicates these are alternatives which may be similar or slightly less or more appropriate.CostingMaintain FIFO, Average, Lot, Last, and Standard costs for each individual part master. The application retains transactional cost and quantity granularity; therefore the oldest cost can be determined for the cost of sales.Cost TrackingSeparately track material cost, material burden, subcontracting, labor, and burden costing.Country of OriginCountry of Origin offers the ability to track the countryof origin at a part level, to define and then report on the composition, by percent, the specific countries of origin for that part. Composition is made available to EDI, manifest, packing slips, and label print.Cycle Counting and Physical InventoryManagement and control of inventory is critical. Furthermore, in some regions such as Europe, the control and counting of inventory on a regular and scheduled basis helps significantly reduce annual audit costs. The cycle counting module contains the breath of functionality and features needed for usersto provide:• Detailed audit control over the selection of items tobe counted• The frequency over the number of times these items are counted• The tracking, recording, and review of variances for the items countedThe system will allow for the definition of the number of cycles required, counting of zero quantity on-hand, etc., and the assignment/designation of the items with an appropriate ABC code. In addition, Physical Count processes allows control over Slow Moving, Obsolete and Excess Inventory.Global Trade StandardsFor companies that are required to work within global trade frameworks, Epicor SCM ensures that you can meet the many international standards. At a part level the user can define the global trade standards for the part (UPC UCC-12, EAN UCC-13, EAN UCC-8, GTIN-14 etc). When codes are assigned to a part, a global trade standard bar code can be scanned at any part number field which automatically relates the transaction to the correct inventory part.Lot Tracking and Lot AttributesProvides visibility of parts by lot throughout the system. Record material received by lot, keep traceable material on-hand by lot, and maintain detailed usage information by lot at every levelof the process. In support of more detailed and complete lot tracking needs Epicor has provided the ability to allow additional lot attributes to be stored for each part lot and the option to allow the system to generate lot numbers based on part specific rules. Examples of the additional Lot attributes include; Batch, Manufacture Lot, Heat Number, Manufacture Date, Expiration Date, Firmware Version, Cure Date, Best Before Date, etc. Manufacturers Part Cross ReferenceEpicor can hold cross references for a manufacturer’s part,so that receiving/inspection can confirm that the part they received is one of the correctly identified parts for the qualified part manufacturer.Online Part TrackerView parts, purchase orders, sales orders, quotes, and jobs to analyze current requirements and track pending receipts.Part Cross ReferencingThis functionality allows the user to create any number of cross-reference codes to a single inventory part. Thesecross-reference codes could be a Customer’s Part Number, Supplier’s Part Number, Manufacturer’s Part Number, or just a simple internal shortcut. When the cross-reference is for a serial tracked part, then for each cross-reference created, a serial number format can be defined which will then be used when serial numbers are created using the cross-reference item number.Part Master Price BreaksSet up price breaks, including effectivity date, per inventory part/supplier.Physical and Perpetual InventoryEnter physical counts, print gain/loss reports and updateon-hand inventory levels.RoHSRestrictions on use of certain Hazardous Substances (RoHS) EU directive instructs companies that sell electronic equipment in the European Union to reduce (under published threshold values) 6 Hazardous Substances from certain types of electronic equipment. The main aim of the RoHS directive is to prevent hazardous materials entering waste landfill sites. Other legislative bodies in other regions outside the EU have similar restrictions or are planning to implement a similar system including China, Japan, and California. Epicor delivers the ability for parts to have a compliance status in accordance with various legislative requirements and to track the consumption and disposal of those targeted parts.Serial TrackingSerial Tracking ensures product traceability, allowing for greater control over how the user wishes to control serial tracked parts within the facility. These options range fromno serial tracking through to full serial traceability when each move of a part is recorded, and a record is maintained of the lower level serial tracked components that were used in the manufacture of part. A further option with serial tracking is the ability to record serial numbers at the outbound stage only. This option is aimed specifically valuable for supplychain users that need to record what serial numbers have been shipped to which customers and when, but they do not want the overhead of having to record the serial numbers as the inventory moves around the warehouse or between the manufacturing plant and distribution warehouse where the products are produced in-house.Serial DocumentationPrint serial numbers on all outgoing communication with the customer such as the packing slip and invoice.Control inventory and significantly reduce annual audit costs.Serial Number TrackerSerial Number Tracker provides an online view into the movement of the product after the serial numberwas assigned.Serial Number Assignment to PartsAssign serial numbers to finished parts and raw materials processed throughout the system.Serial Number FormattingFormat serial numbers as either numeric or alphanumeric and assign the number of characters for the field as wellas a prefix.Voided SerialAllows for the voiding of serial numbers to ensure they are no longer available in the assignment/ selection browser.Time-Phased Material Inquiry/ReportProvide analysis within a user-defined time period onthose parts where projected requirements exceedavailable quantities.Unit of MeasureBase level UOM definitions with UOM Classes and conversions are just a few of the features found in Epicor as well as the ability to allow the user to select the unit of measure in which they wish to hold their inventory. When a part is defined to be tracked in multiple UOMs, then the user will have visibility of how many items they have in the different units of measure.A distributor can stock items, for example, as each, in boxes of 10, in cases of 20 or in pallets of 40 boxes. A user will be able to see exactly how many of each UOM they have inventory and where they are located. This feature is also invaluableto businesses that use raw materials that they purchase in different sizes (i.e., 6x3 sheets or 8x4 sheets, etc.). Advanced Material Management Advanced Material Management (AMM) enables businessesto produce electronic requests for materials, dispatch those materials, and track inventory movements of all inventory including raw materials and work in process. Using wireless terminals and bar coding technology you are able to track inventory in real-time with complete control and visibility of raw materials and work in process as it travels throughoutthe enterprise.Bar Coding on DemandPrint tags on demand enabling employees to properly label containers or to create custom labels (via Seagull Scientific, Inc. BarTender®) to meet customer requirements.HandheldAllows for the transaction of work either on a graphicaltouch screen station or via mobile Radio Frequency (RF) enabled device.Material Handler InterfaceUse an online queue of raw material and WIP parts to manage requests to locate and deliver the right parts to the correct resource at the appropriate time.Material MovementDifferent movement transactions are available for you to move a job to stock, move stocked material, or perform different returns to a job or stock.Prioritizing OrdersLets you treat your best customers with the highest priorityby automatically allocating inventory to the highest priority orders first. Reserve or allocate materials from stock or directly from a linked job to make certain that you ensure your highest priority customers the greatest care.Reserving InventoryReserve specific parts in inventory for designated orders.Sales Order AllocationManage sales order allocations with greater efficiency and create more effective picking and shipping.ScanningEliminate data entry mistakes and increase transactionspeed by simply scanning a bar code tag to complete an entire transaction.Shipping and ReceivingShipping and Receiving provides a central application within Epicor to monitor incoming and outgoing items, whether they are shipments against an order, subcontract partsbeing sent to a supplier, raw material being received from a purchase order to a job or into inventory, or filling an order from stock. All activity relating to shipments and receipts can be performed and tracked. Online transaction processing promotes efficiency and ease of use, while online editing promotes accuracy. With Shipping/Receiving, a consistent interface processes all shipments and receipts in an efficient, accurate and cost-effective manner.Auto-InvoiceOptionally create an invoice in Accounts Receivable following shipment to a customer.Bill of LadingPrint customizable bill of lading forms for your shipments. Container TrackingContainer Tracking provides the ability to track container shipments as well as update the status and due dates of all purchase orders along the way.• Container Shipment - When a container is shipped from the supplier, a notification is received with the actualshipment date, the estimated arrival date, as well as the volume specification of the shipped goods. Based on this information the related purchase order releases can beupdated with new due dates and quantities.• Container Receipt - When a container is received, a PO receipt is automatically generated based on theinformation of the container entered at shipment. With the volume information the expected transport cost can be calculated, which can be used to populate the landed cost information.• Container Class - A container class defines the characteristics of common containers including volumeand default cost information.Customer Shipment TrackerTrack shipments that have been sent to customers.Landed CostAllows businesses to track those costs accurately againstthe parts to which they apply, ensuring that the selling or assembly price then reflects the true cost of the materials, parts or finished goods. The cost of freight, insurance and import duties can have a big impact on margins, so landed cost processing offers significant benefits for those customers who import materials on a regular basis.This functionality includes: uplift percentage of cost you put above your costs, duties, defines tariff rates in Import tariff table (rate, percent, fixed amount, min/max), indirect cost, split container shipments (some containers are delayed), and transfer indirect costs from one shipment to another. Manifesting and Freight ManagementProvides the freight cost calculations and compliant package labeling for the majority of commercial carriers such as UPS™, FedEx®, DHL, USPS® as well as Less-Than-Truckload (LTL) and ad hoc carriers.Mass ShipOptionally mass release shipping lines from orders with same ship-to addresses.Subcontract PartsTrack shipments and receipts of subcontract items online. Receipt TrackerTrack receipts for goods that you have received. Miscellaneous Shipment TrackerView information about miscellaneous shipments. Miscellaneous ReceiptsEnter online any miscellaneous receipts to a job orinto inventory.Pack and Ship/Pack Out ProcessingThe Pack Out functionality adds greater flexibility and control to the shipping process by allowing carton level packing and grouping. Carton specific details such as carton weight and exact carton contents are captured with interfaces to allow manifesting (UPS, FedEx, etc.). The Pack Out screen allows for more of a “grocery store“ packing system which requires very little mouse usage for distribution customers who require a very fast and accurate system of tracking carton contents. Pack IDsPack IDs could be a single package, carton, or the contents for an order. Pack IDs could also be pack records for the contents of multiple orders. Allows the printing of pack records tofill orders to customers or ship parts to subcontractors with general or detailed line comments. And Master Packs can hold more than one Pack ID.Master PackMaster pack gives you the ability to track the precise contents of each individual pack ID. It provides the option of one carrier label for the entire master pack or a carrier label for each pack ID. This is useful for when users want to assign a Master Pack ID to a pallet of packages, so they can better track those individual packages on a single pallet that is going to the same customer or same ship-to address. The concept of a master pack is important for international shipments as it greatly reduces the complexity in shipping product over international borders.Phantom PackPhantom Pack provides the ability to ship all items on an order under a single Pack ID. You determine the number of cartons needed, manifest the cartons with the tracking numbers,size and weight and freighted costs, and then generate therequired shipping labels.Customer Shipment Entry is a robust tool for managing the shipping process.Label FormsEpicor leverages Seagull Scientific, Inc. BarTender® software to enable you to create your label or form format in a WYSIWYG interface. These formats are placed in a directory that is available to Epicor. Labels and Forms consist of fixed data or database variable data and can be human readable or barcode format or both.Auto-Print IntegrationThis functionality provides for automatically printing barcode labels upon the completion of defined transactions in the Business Activity Manager program.Label Design: Integrated label and form printing.•Label Printing: Integrated label and form printing.•Shipping LabelsOptionally print customized shipping labels for each order. Labels include the customer’s name and address. They can also include the purchase order number, sales order number, and ship via, number of packages, shipping comment and weight fields.Shipping PerformanceGenerate executive summary of company trends regarding delivery performance, including number of shipments made, percentage of on-time delivery, and average daily variance between customer promise and delivery.Warehouse ManagementManagement of the supply chain requires robust logistics capabilities as part of the overall system. Epicor’s Warehouse Management System (WMS) leverages Epicor True SOA™, mobile ID data collection, and wireless communications to seamlessly link your warehouse with your order processing and manufacturing operations to optimize your pick, pack, ship, and receiving processes. With Epicor, your warehouse becomes a key part of the supply chain.Bin TrackingEnables the tracking of bins based on various attributes (size, location, whether the bin requires a forklifts to access, etc.). Bin WizardEnables the quick creation of large batches of bins—all at the same time.Warehouse TeamsCreate teams of employees with attributes assigned to them such as warehouse, bins, bin zones and items, to enable better resource scheduling.Customer Managed InventoryGives you visibility into inventory owned by your customer and allows you to assign that inventory to a job or sales order for that customer or that customer’s customer. In both cases the Supplier Managed InventoryGives you visibility into inventory owned by your supplier in your warehouse. However, the inventory does not appearin your ledger until you consume those items, either in production or by receiving them to your warehouse. Fulfillment WorkbenchUse the Fulfillment Workbench for allocation or reservation and distribution processing, and plan for sales, transfers and job order types. Various fulfillment techniques, such as pick and pack, console-driven, and pre-pack processes may be performed through the use of templates to automate the fulfillment process for each. Hard allocation to finite level, versus reservations processing, may be launched directly from the order, line, and release areas as well. This feature also includes cross-docking capability.Allocation TemplatesAutomates the allocation of inventory for picking, with pre-defined criteria such as bin, zone, lot, serial number.Wave PickingProvides the ability to group orders by warehouse area or zone, allowing the fulfillment worker to pick items in one fell swoop for multiple orders. This reduces the number of times a fulfillment worker must return to the same area to pick items.Cross Dock TrackerAbility to view all cross dock orders waiting to be fulfilled by incoming receipts.Paperless PickingUse the handheld to automatically pick orders.View all cross dock orders waiting to be fulfilled by incoming receipts.。
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A Multi-Agent System Architecture for Coordination of Just-in-time Production and Distribution
Paul Davidsson and Fredrik Wernstedt Department of Software Engineering and Computer Science Blekinge Institute of Technology Soft Center, 372 25 Ronneby, Sweden +46-(0)457-385841
{paul.davidsson, fredrik.wernstedt}@bth.se
Abstract A multi-agent system architecture for coordination of just-in-time production and distribution is presented. The problem to solve is two-fold: first the right amount of resources at the right time should be produced, and then these resources should be distributed to the right consumers. In order to solve the first problem, which is hard when the production and/or distribution time is relatively long, each consumer is equipped with an agent that makes predictions of future needs that it sends to a production agent. The second part of the problem is approached by forming clusters of consumers within which it is possible to redistribute resources fast and at a low cost in order to cope with discrepancies between predicted and actual consumption. Redistribution agents are introduced (one for each cluster) to manage the redistribution of resources. The suggested architecture is evaluated in a case study concerning management of district heating systems. Results from a simulation study show that the suggested approach makes it possible to control the trade-off between quality-of-service and degree of surplus production. We also compare the suggested approach to a reference control scheme (approximately corresponding to the current approach to district heating management), and conclude that it is possible to reduce the amount of resources produced while maintaining the quality of service. Finally, we describe a simulation experiment where the relation between the size of the clusters and the quality of service was studied.
Keywords Multi-agent system architecture, District heating, Coordination
1 Introduction Agent-based computing has long been suggested as a promising technique for application domains that are distributed, complex, and heterogeneous [1, 2]. One such application area is the coordination of production and distribution in supply chains. A supply chain is a collection of autonomous or semiautonomous suppliers, factories, and distributors, through which raw materials are acquired, refined and delivered to customers. The supply network is often represented as a network similar to the one in Figure 1, where resources flow (are transported) “downstream” from raw material suppliers, to tier suppliers, to manufacturers, to distribution
centers and retailers, and finally to customers.
Figure 1. Example of a supply chain network. Raw material suppliers Flow of resources (transportation) Tier suppliers Manufacturers Distribution centers and retailers Customers This is a somewhat simplified view, e.g., resources may also flow upstream and the network is rarely static with regard to the number of participants. The traditional goal of supply chain management is cost optimization with respect to fixed demand. This often involves a trade-off between different objectives, e.g., consider the trade-off between customer service, measured in delivery time, and transportation cost. Also, a typical supply chain faces uncertainty in terms of both supply and demand. Thus, one of the most common problems faced by managers concerning production decisions is to anticipate the future requirements of customers
In this paper, we will focus on Just-In-Time [3] production and distribution of resources where the production and/or distribution time is relatively long. By relatively long, we mean in relation to changes in customer demand, i.e., systems where it is impossible to immediately and dynamically compensate for such fluctuations by increasing/decreasing the production. We suggest a multi-agent system (MAS) architecture for solving this problem and investigate its performance.
A characterization of the general problem of coordination of just-in-time production and distribution is followed by a short survey on approaches to optimization of supply chain management. Then a general description of a MAS architecture that solves this problem is given. We briefly describe the principles of district heating systems, which is the domain that has been chosen for a case study, and how the MAS architecture has been adapted to this particular domain. Finally, some results and an analysis of simulation experiments are followed by conclusions and pointers to future work.