CAD for process plants: an update

We review the availability of CAD software for the process design activities of physical properties generation, unit operation design, flowsheeting and dynamic flowsheet simulation. Similarly we look at CAD software for materials control, piping documentation and pipe stressing. We report conclusions drawn from our research into the provision and use of CAD turnkey systems for producing schematics at the conceptual design phase, and for equipment specification, layout, piping design and 3D modelling at the engineering design phase.By reviewing the shortcomings of current CAD systems along with developing CAD technology, we were able to specify the requirements of the next generation of process plant CAD.     

Design Rationale for a Wide Spectrum Specification Language FGSPEC

FGSPEC is a wide spectrum specification language intended to facilitate the software specification and the expression of transformation process from the functional specification whic describes “what to do ”to the corresponding design(perational)specification whic describer“how to do ”.The design emphasizes the coherence of multi-level specification mechanisms and a tree structure model is provided whic unifies the wide spectrum specification styles from“what”to“how”.     

Collaborative conceptual design: A large software project case study

During software development, the activities of requirements analysis, functional specification, and architectural design all require a team of developers to converge on a common vision of what they are developing. There have been remarkably few studies of conceptual design during real projects. In this paper, we describe a detailed field study of a large industrial software project. We observed the development team's conceptual design activities for three months with follow-up observations and discussions over the following eight months. In this paper, we emphasize the organization of the project and how patterns of collaboration affected the team's convergence on a common vision. Three observations stand out: First, convergence on a common vision was not only painfully slow but was punctuated by several reorientations of direction; second, the design process seemed to be inherently forgetful, involving repeated resurfacing of previously discussed issues; finally, a conflict of values persisted between team members responsible for system development and those responsible for overseeing the development process. These findings have clear implications for collaborative support tools and process interventions.     

从功能规格说明到设计规格说明的自动转换

本文介绍了算法自动设计的研究背景与设计思想,提出了一种算法设计自动化模型及其形式化的软件规格说明语言表示,并详细讨论了一些常用算法设计方法的自动实现技术.     

软件构架中接口设计方法

该文强调了软件构架中接口设计的必要性,介绍了5个方面的设计原则;给出了接口描述规范,介绍了5个指导方针;描绘了接口设计的标准结构(包含9个部分);罗列了接口可能的涉众;阐述了接口的表示方法;用具体的实例展示了这些方法在实践中的应用。     

通过遗传算法进行系统级软硬件划分

介绍采用遗传算法解决软硬件划分问题，具体讨论在遗传算法实现过程中的编码和解码，适应值函数的选取，选择，交叉，变异算子的实现、收敛准则的决定等问题的处理，与已发表文献的处理方法进行比较，最后通过随机实验取得好的结果。     

BCOOPL: A Language for Controlling Component Interactions

This paper introduces BCOOPL, which stands for Basic Concurrent Object-Oriented Programming Language. BCOOPL was designed to support component-based development. In particular, it focuses on the specification of weakly-coupled components and the specification of interaction sequences between them. BCOOPL supports two design patterns directly. The built-in observer design pattern encourages the construction of weakly-coupled components. Its support for the mediator design pattern allows to govern the interactions between those components. These language features cater for the design and implementation of flexible systems in which specifications of individual component behavior is separated from specifications of component interactions. A high level overview of BCOOPL's key concepts is given, which are exemplified by means of a process control example.     

面向对象软件规格语言的设计

本文提出一种面向对象软件的形式描述语言JOOSL，用它可描述面向对象软件需求规格、概要设计和详细设计。从描述方法角度看，需求规格和概要设计的描述在很大程度上相同，这就反映了OO开发模型中需求和设计之间的重叠。在这些描述中用抽象方法描述数据和操作；详细设计中确定算法细节和数据的表示。JOOSL 认为对象是一种抽象的状态机，继承是行为特性的共享。     

面向对象的软件构造

面向对象技术的发展改变了传统软件系统的结构和设计方法学．本文作者提出一种称为ＳＣＯＰ的面向对象的软件系统结构模式，即软件是对象模块的复合，而软件设计则是对象模块经过程控制进行复合的构造生成．本文从语义模型、描述语言、设计方法学和支持环境等几方面对ＳＣＯＰ进行扼要的介绍．     

结合形式化的面向对象设计方法与支撑系统

为了有效地结合形式化和非形式化设计方法各自的优点,克服其不足之处,以尽可能保证软件设计的质量与可靠性,文章提出了一种将形式化方法与非形式化的面向对象设计方法ＨＯＯＤ（ｈｉｅｒａｒｃｈｉｃａｌｏｂｊｅｃｔ－ｏｒｉｅｎｔｅｄｄｅｓｉｇｎ）相结合的途径,并介绍了其机器支撑环境的设计与实现．该途径在对层次式面向对象设计方法ＨＯＯＤ进行必要扩充的基础上,有机地集成了Ｚ语言等形式规约技术．支持这一途径的支撑环境提供了一套方便灵活的图形构筑工具、语法制导的形式语言与文本编辑工具,以及自动检查机制等．     

Association algebra: a mathematical foundation for object-orienteddatabases

The application of the object-oriented (O-O) paradigm in the database management field has gained much attention in recent years. Several experimental and commercial O-O database management systems have become available. However, the existing O-O DBMSs still lack a solid mathematical foundation for the manipulation of O-O databases, the optimization of queries, and the design and selection of storage structures for supporting O-O database manipulations. This paper presents an association algebra (A-algebra) to serve as a mathematical foundation for processing O-O databases, which is analogous to the relational algebra used for processing relational databases. In this algebra, objects and their associations in an O-O database are uniformly represented by association patterns which are manipulated by a number of operators to produce other association patterns. Different from the relational algebra, in which set operations operate on relations with union-compatible structures, the A-algebra operators can operate on association patterns of homogeneous and heterogeneous structures. Different from the traditional record-based relational processing, the A-algebra allows very complex patterns of object associations to be directly manipulated. The pattern-based query formulation and the A-algebra operators are described. Some mathematical properties of the algebraic operators are presented together with their application in query decomposition and optimization. The completeness of the A-algebra is also defined and proven. The A-algebra has been used as the basis for the design and implementation of an object-oriented query language, OQL, which is the query language used in a prototype Knowledge Base Management System OSAM*.KBMS     

Algorithm Simplification through Object Orientation

The object-oriented (O-O) approach is claimed to have a number of advantages. Some support to these claims appeared during an O-O redesign of a legacy CAD system. A surprisingly simple and efficient solution algorithm was discovered for a change propagation problem. The analysis of the case employs the new concepts of implementation and extension complexity, which indicate the amount of code (software costs) required for the implementation and for later extensions. These two complexities are functions of the problem complexity, expressed by the number N of object types employed to model the problem domain. Moving from the old system to the new O-O system reduced the implementation complexity from O(N²) to O(N); the extension complexity is reduced from O(N) to O(1). The two systems have the same space and time complexities. The CAD system is employed for designing structures composed of parts. The O-O analysis attempts to analyse each part type separately, which proved to be possible. The corresponding N different object types can therefore be developed independently of each other. The top down analysis employed for the old algorithm did not discover the simple architecture, because it is not geared to look for this kind of solution. Instead it analyses the N² different change propagation cases. The methodical search for independent modules is an important reason for preferring O-O analysis. © 1997 by John Wiley & Sons, Ltd.     

A Simulation Framework for Heterogeneous Agents

We introduce a generic simulation framework suitable for agent-based simulations featuring the support of heterogeneous agents, hierarchical scheduling, and flexible specification of design parameters. One key aspect of this framework is the design specification: we use a format based on the Extendible Markup Language (XML) that is simple-structured yet still enables the design of flexible models. Another issue in agent-based simulations, especially when ready-made components are used, is the heterogeneity arising from both the agents' implementations and the underlying platforms. To tackle such obstacles, we introduce a wrapper technique for mapping the functionality of agents living in an interpreter-based environment to a standardized JAVA interface, thus facilitating the task for any control mechanism (like a simulation manager) because it has to handle only one set of commands for all agents involved. Again, this mapping is made by an XML-based definition format. We demonstrate the technique by applying it to a simple sample simulation of two mass marketing firms operating in an artificial consumer environment.     

DCS图形子系统设计方法探讨

ＤＣＳ是一种新型的控制系统。利用面向对象技术与传统设计思想相结合的方法是目前ＤＣＳ软件开发的一种最佳途径。为了使图形系统软件开发能达到标准化及规范化，进而实现图形系统自动生成的通用环境，本文提出了图形系统设计的一种通用标准设计形式。这也是实现图形处理通用环境的一种途径，是一种新探讨。     

A CASE-tool oriented approach for embedded systems design

The process of successfully creating an embedded system is highly challenging and complex; engineers typically operate under tight financial, technical and time-to-market constraints. To achieve the desired objective, the design team need to utilise effectively the most advanced software tools available, in order that the task may be completed to specification in a timely and cost-effective manner. This paper discusses the use of a CASE-tool in an embedded systems design, and reviews issues pertaining to the integration of such a tool into an embedded systems development environment. The paper focuses on the application of this high level approach in embedded systems design and concludes by describing the use of the CASE-tool in the design of a simple demonstrator.     

Layered specifications to support reusability and integrability

Building systems by integrating components and building systems by reusing components are but two sides of the same coin. In both cases one faces the problem of producing systems out of prefabricated parts, either parts which have been designed for a different environment than the one they will be used in now, or parts which have been designed for a yet undefined target system.This situation differs from classical software design situations. It demands that in parts engineering as well as in systems engineering, certain interface decisions are postponed to a rather late point in time. This is only permissible, though, if other aspects are very precisely specified. Having the right model of specification of both, the target (system) and source (component) will substantially aid the retrieval and integration problem.This article argues for a layered approach towards system specification. It will show, how relational specifications will help system designers not to bind themselves too early into premature decisions and how designs aiming for heavy reuse can grow by stepwise enriching specifications.     

面向对象的组合软件工程研究

组合软件工程技术是当今软件工程技术发展的主流。本文综述了作者在基于对象的组合软件工程研究方面的最新进展，包括语义模型、描述语言、设计方法学和支持环境等方面。     

Development of a sequential robust–tolerance design model for a destructive quality characteristic

Robust design (RD) and tolerance design (TD) have received much attention from researchers and practitioners for more than two decades, and a number of methodologies for modeling and optimizing the RD and TD processes have been studied. However, there is ample room for improvement. Because most existing research considers RD and TD as separate research fields, the primary objective of this paper is to develop a sequential robust–tolerance design method to jointly determine the best factor settings and the closed-form solutions for the optimal specification limits. We then apply the proposed method to a destructive quality characteristic. Finally, a case study and sensitivity analyses are performed for verification purposes, and further studies are discussed.     

Object-oriented approach to interactive analysis of structures

The paper presents a novel, object-oriented (O-O) approach to structural modeling and analysis to enable interactive, virtual prototyping in the next generation of the design environment. The interactivity of analysis of build-up structures can only be achieved by re-using results of component analyses, therefore, the applicability of data based analysis to the O-O approach is investigated in this paper. An object in the O-O approach is a neurocomputing model of a structural component developed for a given set of parameterized design variables, loading, and “smart” connectors. Such connectors define how the given component is connected to the assembly, and what is the validity of such a connection. Since component models can be subject to affine transformations, a family of similar structural components is available for modeling. Neurocomputing models are used to enable data based analysis, because they can relate any design variables and load conditions to the selected system response. The applicability of feed-forward and feature-sensitive neural nets is examined in this context. Object-oriented modeling is illustrated with a design of an assembly of beams using a single-point (SP) connector and an assembly of plates subject to a thermal load using a multi-point (MP) connector.     

Applying an Agent-Oriented Methodology to the Design of Artificial Organizations: A Case Study in Robotic Soccer

The multi-agent paradigm is widely used to provide solutions to a number of organizational problems related to the collective achievement of one or more tasks. All these problems share a common difficulty of design: how to proceed from the global specification of a collective task to the specification of the local behaviors to be provided to the agents? We have defined the Cassiopeia method whose specificity is to articulate the design of a multi-agent system around the notion of organization. This paper reports the use of this method for designing and implementing the organization of a soccer-playing robotic team. We show why we chose this application and how we designed it, and we discuss its interest and inherent difficulties in order to clearly express the needs for a design methodology dedicated to DAI.