基于工作流的企业业务过程集成建模方法

工作流管理是一种对业务过程进行支持、控制、监视和优化的先进工具. 将生产制造过程 BOM和Petri 网技术应用于企业业务过程,对于相关定义、建模分析以及从BOM到Petri 网的映 射实现算法进行了说明;对基于BOM- Petri 的建模方法进行了扩展优化;最后结合算法进行了 仿真研究.     

基于面向对象着色Petri网的工作流的研究

工作流管理一直是企业界和学术界研究的热点,而建模是工作流管理的基础,目前许多工作流模型都存在一定的局限性.Petri网具有是分析非线性自适应系统的良好工具,拥有强大的建模分析能力和算法,与着色Petri网结合,可以找到一种面向对象的工作流过程模型建模方式.     

基于Petri网的工作流优化分析

工作流管理技术是实现企业业务过程重组、过程管理与过程自动化的核心技术。在工作流参考模型中,工作流验证和优化是过程定义工具的重要组成部分。在综述相关研究论文和经典Petri网理论的基础上,提出了基于Petri网的工作流合理性验证算法和过程优化算法。最后通过保险索赔过程的优化实例,验证了工作流优化算法的有效性。     

基于高级Petri网的工作流分析模型研究

工作流管理的目的是控制、监督、优化和支持企业流程.而企业要在竞争激烈的环境中取胜,需要经常实施企业流程再造.为有效支持企业流程再造,企业面临着选择合适的业务流程实施工作流管理的问题.本文针对这一问题,提出了基于高级Petri网的工作流分析模型及规范化的建模方法.这种建模方法能够方便地实现对业务流程的建模,描述企业中多个工作流的动态特性.     

工作流技术在流程分析中的应用研究

流程建模、仿真和优化是企业变化管理的重要内容.工作流技术是近年来发展起来的流程管理信息集成技术,它为流程重组优化提供了有力的支持.但目前工作流的仿真能力还是比较薄弱的环节.另一方面出现了许多有效的流程建模和仿真工具,但它们的功能多是孤立的,大多不能支持建模、仿真和优化等环节的集成.为此探讨了它们在企业变化管理生命周期中的结合方法.上述结合综合了工作流和面向对象建模、Petri网仿真能力等方法的优点,增强了对流程的管理功能.     

基于时间工作流的REA模型改进研究

起源于事项法的REA模型,全面突破了事项法的基本思想,是现代会计信息系统模式开始的标志。但其在对业务流程建模的支持,对事项信息的捕捉,对领域本体的支持等方面存在缺陷。本文借鉴了工作流管理的研究成果,工作流模型的核心是过程模型,其中,Petri网模型是一种理想的过程建模语言,适合描述异步并发现象,既有严格的形式定义,又有直观的图形表示,具有严格的数学基础和规范化的语义,与REA模型具有共通性和互补性。本文应用时间Petri网流程模型对REA模型进行改进,并给出初步实现过程,有效解决了REA模型中存在的问题,并对REA相关领域的研究方向进行展望。     

工作流协同系统性能评价研究

利用广义随机Petri网系统性能分析的优势,在组织间工作流模型基础上引入时间因素,并利用Petri网对局部工作流之间不同通信关系进行描述,最终构建了时间组织间工作流模型,为工作流协同系统性能评价问题提出了解决思路.     

基于CPN的信息系统资源配置动态模型的建立

针对信息资源配置问题提出了一种基于有色Petri网的规范化建模方法,并对整个建模过程进行了详细的描述.提出了系统层次模型结构和执行图的概念,对执行图和Petri网之间的转换过程进行了分析、定义,从而减少了大系统建模的复杂程度和工作量.利用相关的计算机工具,可以方便地实现系统建模和对信息资源配置情况的评价、分析和调整.     

面向角色的多agent 工作流模型研究

目前的工作流建模工具大多是面向活动、面向产品、面向目标或面向决策的,没有强调工作流 是多个角色主体协作的过程,工作流的绩效最终依赖员工及其角色的作用. 从角色及其合作的角 度,分析了面向角色的工作流模型及其表示方法,为工作流的管理提供新的思路. 在此基础上,研究 了角色、agent 和工作流的关系,给出了一种面向角色的工作流多agent 管理系统模型和原型.     

面向角色的多agent 工作流模型研究

目前的工作流建模工具大多是面向活动、面向产品、面向目标或面向决策的,没有强调工作流是多个角色主体协作的过程,工作流的绩效最终依赖员工及其角色的作用.从角色及其合作的角度,分析了面向角色的工作流模型及其表示方法,为工作流的管理提供新的思路.在此基础上,研究了角色、agent和工作流的关系,给出了一种面向角色的工作流多agent管理系统模型和原型.     

New developments in generative BOM processing systems

Abstract

The principle of generative bill-of-material (BOM) processing systems is that different BOMs belonging to different product variants can be represented by a single, so-called source BOM. The BOM processing systems comprise additional data structures which hold information on the relationships between product characteristics of parent product variants and component product variants, and on the relationships between characteristics of a parent product variant and its BOM data. These relationships allow the automatic generation of the individual BOM of each represented product variant. There are several alternative ways of implementing a generative BOM processing system. The oldest concept known is the variant BOM concept. This concept provides a relatively simple solution to deal with large varieties of final product variants. However the concept has a number of drawbacks such as the representation of product variety at lower levels in the product structure and data redundancy which hampers data maintenance. In this paper an improved concept for generative BOM processing systems is introduced and described: the generic BOM concept. The generic BOM concept does not focus on representing final product variants only, but takes a broader view towards representing any range of product variants at any level in the product structure. This starting point solves a number of draw-backs implied by the variant BOM concept but it also requires new definitions of BOM relationships and the introduction of new data structures to support the generation of individual BOMs.     

Manufacturing bill-of-material planning

The bill-of-material BOM in the machine tool industry takes two different forms in design and manufacturing functions: Engineering BOM E BOM , which is used by the design engineer to represent designed product structure; and manufacturing BOM M BOM , which is used by MRPII system for MRP explosion. The designer constructs the E BOM after the product has been designed. Next, the E BOM is transformed into the M BOM by considering assembly sequence and constraints. Constructing a M BOM simply involves compressing the E BOM into a three-level M BOM. Planning of a M BOM still depends primarily on the experience input of a manufacturing engineer and is performed manually. This trial and error and time consuming approach creates an inconsistent method for planning the M BOM. Therefore, in this study, a three-stage M BOM planning method is developed. Stage one plans the initial M BOM, stage two improves the M BOM and stage three tunes the M BOM. Concepts and algorithms of each stage are highlighted in this study. Moreover, an illustration is presented to demonstrate the feasibility of M BOM planning.     

Assemble‐to‐Order Inventory Management via Stochastic Programming: Chained BOMs and the M‐System

We study an inventory management mechanism that uses two stochastic programs (SPs), the customary one‐period assemble‐to‐order (ATO) model and its relaxation, to conceive control policies for dynamic ATO systems. We introduce a class of ATO systems, those that possess what we call a “chained BOM.” We prove that having a chained BOM is a sufficient condition for both SPs to be convex in the first‐stage decision variables. We show by examples the necessity of the condition. For ATO systems with a chained BOM, our result implies that the optimal integer solutions of the SPs can be found efficiently, and thus expedites the calculation of control parameters. The M system is a representative chained BOM system with two components and three products. We show that in this special case, the SPs can be solved as a one‐stage optimization problem. The allocation policy can also be reduced to simple, intuitive instructions, of which there are four distinct sets, one for each of four different parameter regions. We highlight the need for component reservation in one of these four regions. Our numerical studies demonstrate that achieving asymptotic optimality represents a significant advantage of the SP‐based approach over alternative approaches. Our numerical comparisons also show that outside of the asymptotic regime, the SP‐based approach has a commanding lead over the alternative policies. Our findings indicate that the SP‐based approach is a promising inventory management strategy that warrants further development for more general systems and practical implementations.     

Algorithms for the workflow satisfiability problem engineered for counting constraints

The workflow satisfiability problem (WSP) asks whether there exists an assignment of authorized users to the steps in a workflow specification that satisfies the constraints in the specification. The problem is NP-hard in general, but several subclasses of the problem are known to be fixed-parameter tractable (FPT) when parameterized by the number of steps in the specification. In this paper, we consider the WSP with user-independent counting constraints, a large class of constraints for which the WSP is known to be FPT. We describe an efficient implementation of an FPT algorithm for solving this subclass of the WSP and an experimental evaluation of this algorithm. The algorithm iteratively generates all equivalence classes of possible partial solutions until, whenever possible, it finds a complete solution to the problem. We also provide a reduction from a WSP instance to a pseudo-Boolean (PB) SAT instance. We apply this reduction to the instances used in our experiments and solve the resulting PB SAT problems using SAT4J, a PB SAT solver. We compare the performance of our algorithm with that of SAT4J and discuss which of the two approaches would be more effective in practice.     

不确定条件下不同交货期窗口的Job Shop 调度

研究了具有不同交货期窗口的Job Shop 的提前/ 拖期调度问题,并考虑了处理时间的不确定 性,采用三角模糊数表示处理时间的不确定性,提出了基于遗传算法的求解算法. 仿真实验验证了 算法的有效性.     

Stationary Equilibria in Asset‐Pricing Models with Incomplete Markets and Collateral

We consider an infinite‐horizon exchange economy with incomplete markets and collateral constraints. As in the two‐period model of Geanakoplos and Zame (2002), households can default on their liabilities at any time, and financial securities are only traded if the promises associated with these securities are backed by collateral. We examine an economy with a single perishable consumption good, where the only collateral available consists of productive assets. In this model, competitive equilibria always exist and we show that, under the assumption that all exogenous variables follow a Markov chain, there also exist stationary equilibria. These equilibria can be characterized by a mapping from the exogenous shock and the current distribution of financial wealth to prices and portfolio choices. We develop an algorithm to approximate this mapping numerically and discuss ways to implement the algorithm in practice. A computational example demonstrates the performance of the algorithm and shows some quantitative features of equilibria in a model with collateral and default.     

面向在线定制的配置BOM及约束下在线配置过程研究

分析了顾客在线定制产品时重视的因素;提出了面向在线定制的配置BOM的概念,并且详细介绍了其具体内容;定义了在线配置过程的原则和配置依据;应用配置矩阵对零部件和零件属性的配置过程进行了详细的分析,同时给出了配置后产品的价格计算方法.在文章结论中,将本文提出的概念和方法与文献中提到的方法进行了仔细的比较,总结出其主要优势.     

A new slacks-based measure of Malmquist–Luenberger index in the presence of undesirable outputs

In the majority of production processes, noticeable amounts of bad byproducts or bad outputs are produced. The negative effects of the bad outputs on efficiency cannot be handled by the standard Malmquist index to measure productivity change over time. Toward this end, the Malmquist–Luenberger index (MLI) has been introduced, when undesirable outputs are present. In this paper, we introduce a Data Envelopment Analysis (DEA) model as well as an algorithm, which can successfully eliminate a common infeasibility problem encountered in MLI mixed period problems. This model incorporates the best endogenous direction amongst all other possible directions to increase desirable output and decrease the undesirable outputs at the same time. A simple example used to illustrate the new algorithm and a real application of steam power plants is used to show the applicability of the proposed model.