An Arc-Consistency Algorithm for Dynamic and Distributed Constraint Satisfaction Problems

This paper presents the new DDAC4 algorithm for dynamic arc consistency enforcement in distributed constraint satisfaction problems (CSP). The algorithm is an adaptation of the well-known AC-4 algorithm to system settings where constraints can be added and deleted in concurrent processes. It is the first algorithm for arc-consistency enforcement in this system setting. Arc-consistency is achieved whenever the overall system reaches quiescence after a constraint is added or deleted.     

An attribute-based and object-oriented approach with system implementation for change impact analysis in variant product design

Variant product design is critical to the continued survival of a product in the demand-changing market. As variant product design involves numerous and concurrent attempts at requirement and product modification, a change impact analysis (CIA) becomes essential in order to capture both the potential and contextual impacts of a change proposal, and thereby ensure the consistency of the product’s integrated content throughout the process of carrying out any changes. In this regard, this paper presents an attribute-based, object-oriented approach for effectively and comprehensively performing the CIA tasks in variant product design. This approach models the integrated content of a product by characterizing its components and associated requirements with attributes and linkages. It then features an object-oriented change propagation design in order to handle the dynamic and recursive CIA loops. This approach is also able to show the collective impact when multiple changes are attempted. A computerized prototype, EPCII_EC, is implemented in order to realize the approach, and an illustrative product case with a comparative evaluation is provided in order to validate the work. Issues and limitations of this study are also discussed and suggestions are provided for future studies.     

装备虚拟维修训练系统工程研究

以虚拟现实技术为基础,提出了装备虚拟维修训练系统建设总体方案,并完成了第一期的建设任务。该系统的实现,对于解决目前存在的复杂装备维修训练问题有重要意义。     

基于动态约束网络的约束优化分解

约束网络通过对较大规模的任务和问题的分解,传递了并行工程产品开发过程中的各多功能小组之间必然存在的相互制约、相互依赖的关系。在任务和问题简单分解的过程中,由于所得到的子问题之间通常是不能完全独立的,因而只能在有限程度上降低难度、简化问题。在分析了约束求解的研究现状和不足的基础上,提出了一种基于动态约束的约束优化分解方法,使得各个子任务、子问题间的关系得到进一步的分解,从而在满足原要求的基础上,得到优化的结果。     

An object-oriented approach for mechanical components design and visualization

In this paper, development of shape modeling tools for engineering design, analysis, simulation, and visualization is presented. The approach based on the idea of function-based shape modeling is combined with the power and versatility of the object-oriented programming (OOP). An OOP code, initially developed as a teaching and learning tool for educational use in an undergraduate Modeling and Simulation course, to generate mechanism components is presented. Different parametric, explicit, and implicit functions or their combination are used to generate mechanical components shapes. Using a blending process, sophisticated shapes have been generated on the graphical interface. However, the ideas and concept of the OOP mechanical components design presented in this paper can be applied to other application areas.     

An anthropocentric approach to knowledge-based preventive maintenance

It is common knowledge today that application of sound manufacturing concepts and techniques will only provide cost-effective, long-term return when manufacturing functions are totally integrated with the operators, maintenance engineers and other associated personnel. This paper presents a human-centred methodology and its associated knowledge-based tool, to utilize equipment failure information for the purpose of machine down-time minimization. Based upon a structured and rigorous assessment of each breakdown, and combined with total employee participation, continuous improvement of maintenance function and operational effectiveness of equipment can be made a reality.     

面向对象设计复杂性度量计算与分析

软件维护在软件开发过程中占有相当重要的位置,但是其成本往往是很难控制的.在对一种能够对软件维护性能进行预测的面向对象复杂性度量进行分析的基础上,结合实际情况分析了该算法集3个度量的缺点及联系.对于3个度量不够深入的地方补充了一些新观点.     

An object-oriented approach to the design of a mail system for a heterogeneous environment

The design of an electronic mail system, MASH, is presented in this paper. The system, to be used in a heterogeneous environment, provides common user interfaces that allow the use of several diverse workstations. It also allows message transmission through different networks. An object-oriented approach is adopted to model the handling of the user interface and communication. This approach results in procedural transparency to users when using the system.     

An AI approach to automate the preliminary design phase of electronic equipment for satellites

This communication reports progress in the automation of the mental process of designing artifacts as a means to shorten design time and improve the quality of artifacts. This investigation is currently being conducted in the SMACK project, a common enterprise between Alcatel Alsthom Recherche and Alcatel Espace to develop a smart preliminary design system applied to the electronic equipment for satellites case-study. We present principles of the SMACK project and those of our running prototype SMACK. Innovative AI features of SMACK are discussed. They include reasoning paradigms we devised to automate the generative and patching activities of design (respectively functional and delta reasonings) and also a complexity-buster constraint-propagation technique which draws upon phenomena exhibited in design by assembly environments.     

Incremental maintenance of object-oriented data warehouses

Incremental maintenance of data warehouses has attracted a lot of research attention for the past few years. Nevertheless, most of the previous work is confined to the relational setting. Recently, object-oriented data warehouses have been regarded as a better means to integrate data from modern heterogeneous data sources. However, existing approaches to incremental maintenance of data warehouses do not directly apply to object-oriented data warehouses. In this paper, therefore, we propose an approach to incremental maintenance of object-oriented data warehouses. We focus on two primary issues specifically. First, we identify six categories of potential updates to an object-oriented view and propose an algorithm to find potential updates from the definition of the view. Second, we propose an incremental view maintenance algorithm for maintaining object-oriented data warehouses. We have implemented a prototype system for incremental maintenance of object-oriented data warehouses. Performance evaluation has been conducted, which indicates that our approach is correct and efficient.     

An object-oriented approach to teaching mathematics for engineering and science students

It is suggested to teach mathematics for engineering and science students as exploration of mathematics-related classes. Similarity with classes and objects of object-oriented programming is demonstrated. In the framework of the suggested approach, each relatively self-contained unit of mathematics curriculum is assigned a data type and is considered a class. In such setting, a theorem proof may be viewed as an assignment of values to object properties. The approach augments the role of recognition of mathematical objects, their properties and methods （operations） and diminishes the value of comprehensive study of rigorous proofs. The approach emphasizes the importance of development of mathematical intuition and combines conceptual and operational approaches to teaching and learning mathematics. Prospective implementation assumes using of computer-based systems of formal proof.     

A Foundation of Solution Methods for Constraint Hierarchies

Constraint hierarchies provide a framework for soft constraints, and have been applied to areas such as artificial intelligence, logic programming, and user interfaces. In this framework, constraints are associated with hierarchical preferences or priorities called strengths, and may be relaxed if they conflict with stronger constraints. To utilize constraint hierarchies, researchers have designed and implemented various practical constraint satisfaction algorithms. Although existing algorithms can be categorized into several approaches, what kinds of algorithms are possible has been unclear from a more general viewpoint. In this paper, we propose a novel theory called generalized local propagation as a foundation of algorithms for solving constraint hierarchies. This theory formalizes a way to express algorithms as constraint scheduling, and presents theorems that support possible approaches. A benefit of this theory is that it covers algorithms using constraint hierarchy solution criteria known as global comparators, for which only a small number of algorithms have been implemented. With this theory, we provide a new classification of solution criteria based on their difficulties in constraint satisfaction. We also discuss how existing algorithms are related to our theory, which will be helpful in designing new algorithms.     

最先失败原则的约束传播算法

约束满足问题是人工智能研究领域的重要问题.而弧相容算法是求解约束满足问题的重要工具.在弧相容算法中应用启发式规则已经证明是一种很有效的方式.本文提出一个基于最先失败原则的约束传播算法,该算法在搜索过程中更早地发现含有空域的变量并提前进行回溯,从而提高问题求解效率.同时,在"明月1.0"架构下实现了该算法,实验结果表明使用最先失败原则的弧相容算法要比原来的算法效率上提高了约40%.     

用三维几何约束构建概念化设计阶段的三维布局

概念化设计是产品设计中的一个重要环节,其主要任务是实施产品结构的空间布局,并确定连接关系．由于概念化设计阶段产品结构信息不明确,因此现有的三维设计工具(如solidedge7．0,MDT等)无法有效支持概念化阶段的设计活动．在对装配关系进行抽象的基础上,利用三维约束与驱动实现概念化设计阶段的空间布局设计活动,为进行三维设计工具自顶向下的设计模式奠定了基础．     

EXACT: an extensible approach to active object-oriented databases

Active database management systems (DBMSs) are a fast-growing area of research, mainly due to the large number of applications which can benefit from this active dimension. These applications are far from being homogeneous, requiring different kinds of functionalities. However, most of the active DBMSs described in the literature only provide a fixed, hard-wired execution model to support the active dimension. In object-oriented DBMSs, event-condition-action rules have been propo sed for providing active behaviour. This paper presents EXACT, a rule manager for object-oriented DBMSs which provides a variety of options from which the designer can choose the one that best fits the semantics of the concept to be supported by rules. Due to the difficulty of foreseeing future requirements, special attention has been paid to making rule management easily extensible, so that the user can tailor it to suit specific applications. This has been borne out by an implementation in ADAM, an object -oriented DBMS. An example is shown of how the default mechanism can be easily extended to support new requirements. Edited by Y. Vassiliou. Received May 26, 1994 / Revised January 26, 1995, June 22, 1996 / Accepted November 4, 1996     

非二元约束满足问题求解

在约束满足问题(CSP)的研究中,大部分工作集中在二元约束,但处理实际问题时,常常会遇到非二元约束的情况．该文在概要地讨论了两类求解非二元约束问题方法的基础上,研究了一种将约束传播技术和一般弧相容回溯算法相结合的非二元约束求解方法,并在设计开发的约束求解工具“明月SOLVER1.0”中实现了该方法,以典型例子给出了实现系统的运行结果．     

约束程序设计语言COPS的设计与实现

约束程序设计作为面向智能应用的实用型程序设计风格正在AI领域产生越来越大的影响,其关键问题是如何将说明性的知识表示、系统化和启发式的推理搜索能力以及合理的确定性计算开销统一起来。该文介绍了设计实现的并发约束程序设计语言COPS。COPS系统的主要目标是探索智能语言的实用化与工程化,使其能够真正解决现实世界中用常规语言难以实现的智能应用问题。还介绍了COPS语言的表示及涉及的主要推理技术。     

Constraint network approach to the design and manufacture of labels in a high-variety label-printing environment

This paper presents a constraint network approach to the design and manufacture of high-variety labels. The existing approach to label printing in the industry is essentially a sequential approach. In this approach, layout sheet utilization is optimized based on label attributes only. Production then attempts to meet delivery date of the labels by first processing high-priority labels from the layout sheet, and others later. This results in huge work-in-process inventory and high production cost. In this paper, we propose a constraint network approach to the design and manufacture of labels on layout sheets. Mathematical models of the various manufacturing stages are considered in the design process. Thus the emerging optimal layout design minimizes the work-in-process inventory and production cost, and maximizes production efficiency. The algorithm is an application of artificial intelligence techniques in a system domain. An example application of the algorithm results in an efficient production schedule and greater product delivery performance.