Correct architecture refinement

A method is presented for the stepwise refinement of an abstract architecture into a relatively correct lower-level architecture that is intended to implement it. A refinement step involves the application of a predefined refinement pattern that provides a routine solution to a standard architectural design problem. A pattern contains an abstract architecture schema and a more detailed schema intended to implement it. The two schemas usually contain very different architectural concepts (from different architectural styles). Once a refinement pattern is proven correct, instances of it can be used without proof in developing specific architectures. Individual refinements are compositional, permitting incremental development and local reasoning. A special correctness criterion is defined for the domain of software architecture, as well as an accompanying proof technique. A useful syntactic form of correct composition is defined. The main points are illustrated by means of familiar architectures for a compiler. A prototype implementation of the method has been used successfully in a real application     

KAD—一个基于知识的住宅方案计算机辅助设计系统

本文介绍了一个基于知识的住宅方案计算机辅助设计系统(KAD)的有关理论、方法及执行技术.KAD以目标规则、设计规则、对象规则的层次结构表示设计知识,并在设计知识的层次表示上实现了层次推理.KAD用住宅基本间作为组合设计的最小单位,通过对设计任务的固定划分和解空间的抽象来减小状态空间的搜索规模,并采用目标引导的产生测试搜索方法来提高搜 索速度.KAD在Apollo工作站上运行并可用于高层塔式住宅的方案设计与分析.     

A knowledge-based approach to design

A framework is presented for constructing knowledge-based aids for design problems. In particular, we describe the organization of an interactive knowledge-based consultant for VLSI design (called VEXED?an acronym for VLSI expert editor), and a prototype implementation of VEXED. The paper focuses on the principles underlying the design of VEXED, and on several lessons and research issues that have arisen from implementing and experimenting with this prototype.     

面向CAD／CAM的数据模型研究

本文通过分析工程领域对数据与知识管理的特殊要求,提出了一个面向CAD/CAM的数据模型——PORR模型.文中着重介绍了PORR模型的基本思想,给出了概念模式、规划模式和规则设计方法以及定义语言,并探讨了版本管理的实现方法和规划控制过程的实现方法.     

Application of knowledge-based approaches in software architecture: A systematic mapping study

ContextKnowledge management technologies have been employed across software engineering activities for more than two decades. Knowledge-based approaches can be used to facilitate software architecting activities (e.g., architectural evaluation). However, there is no comprehensive understanding on how various knowledge-based approaches (e.g., knowledge reuse) are employed in software architecture.ObjectiveThis work aims to collect studies on the application of knowledge-based approaches in software architecture and make a classification and thematic analysis on these studies, in order to identify the gaps in the existing application of knowledge-based approaches to various architecting activities, and promising research directions.MethodA systematic mapping study is conducted for identifying and analyzing the application of knowledge-based approaches in software architecture, covering the papers from major databases, journals, conferences, and workshops, published between January 2000 and March 2011.ResultsFifty-five studies were selected and classified according to the architecting activities they contribute to and the knowledge-based approaches employed. Knowledge capture and representation (e.g., using an ontology to describe architectural elements and their relationships) is the most popular approach employed in architecting activities. Knowledge recovery (e.g., documenting past architectural design decisions) is an ignored approach that is seldom used in software architecture. Knowledge-based approaches are mostly used in architectural evaluation, while receive the least attention in architecture impact analysis and architectural implementation.ConclusionsThe study results show an increased interest in the application of knowledge-based approaches in software architecture in recent years. A number of knowledge-based approaches, including knowledge capture and representation, reuse, sharing, recovery, and reasoning, have been employed in a spectrum of architecting activities. Knowledge-based approaches have been applied to a wide range of application domains, among which “Embedded software” has received the most attention.     

Structural design language for coupled knowledge-based systems

A Structal Design Language (SDL) has been developed in INTERLISP environment for building coupled knowledge-based expert systems for integrated design of a class of structures. The integrated design includes the preliminary design, structural analysis, design of members, design of connections, and computer-aided drafting of the final design. The complex body of knowledge needed for detailed design of a structure is fractionated into smaller and more manageable knowledge sources which are organized into a hierarchy of cooperating conceptual specialists. SDL provides a multiwindow graphics interface capable of displaying both the orthographic and isometric views of the frame structure and beam-column connections. A three-dimensional face frame representation sentation is used for the graphic display of the beam-column connections. SDL has been used to develop a prototype knowledge-based system for integrated design of steel building structures consisting of moment-resisting frames.     

Towards user centred design (UCD) in architecture based on immersive virtual environments

This paper describes a generic concept of how to combine the experience of user centred design (UCD) in the field of Human Computer Interaction (HCI) with the traditional approach of participatory design (PD) in an architectural design process. Even if some basic requirements of this generic method are not available yet, this paper will also describe an approach, which enables planners even now to involve end users by using virtual environments (VE) as immersive and spatial prototype. It will be described and illustrated by the way of example using the building project Centre of Virtual Engineering of the Fraunhofer Institute for Industrial Engineering (IAO) in Stuttgart. It demonstrates that the transfer of the UCD approach to architectural planning combined with the provision of an adequate prototype can make a significant contribution towards an increase in quality and performance in building and construction projects.     

Automated functional design of engineering systems

This paper presents a prototype intelligent system, the knowledge-based functional design automation system (KBFDA) for automating the functional design process of engineering products/systems. An integrated knowledge representation scheme combines rule-based and object-oriented representation methods to represent functions and function related design characteristics in an intelligent design environment. A knowledge-based functional reasoning strategy uses this representation to automatically generate physical behaviors from desired functions or behaviors. The required behaviors are then combined in different configurations to develop a set of potential concept variants that meet the functional requirements and functional constraints given in a design specification. Finally, the variants are ranked according to the degree to which they meet non-functional constraints. The variant with the lowest rank (score) is selected as the best solution. A case study design of a terminal insertion unit is presented to demonstrate the practicality of the proposed approach.     

Decopan Design: a knowledge-based system for industrial controlgear panels design

A wide domain for expert systems application is that of design processes. Decopan Design is a knowledge-based system supporting the design of industrial controlgear panels. Such a design process requires declarative knowledge, heuristic knowledge and human experience and skill, which are excellent subjects in order to be incorporated in a knowledge-based expert system. Decopan Design has been created using an expert system shell and has been linked with a computer-aided drafting program for drawing purposes.     

Data model for extensible support of explicit relationships in design databases

We describe the conceptual model of SORAC, a data modeling system developed at the University of Rhode Island. SORAC supports both semantic objects and relationships, and provides a tool for modeling databases needed for complex design domains. SORAC's set of built-in semantic relationships permits the schema designer to specify enforcement rules that maintain constraints on the object and relationship types. SORAC then automatically generates C++ code to maintain the specified enforcement rules, producing a schema that is compatible with Ontos. This facilitates the task of the schema designer, who no longer has to ensure that all methods on object classes correctly maintain necessary constraints. In addition, explicit specification of enforcement rules permits automated analysis of enforcement propagations. We compare the interpretations of relationships within the semantic and object-oriented models as an introduction to the mixed model that SORAC supports. Next, the set of built-in SORAC relationship types is presented in terms of the enforcement rules permitted on each relationship type. We then use the modeling requirements of an architectural design support system, called Arch Objects, to demonstrate the capabilities of SORAC. The implementation of the current SORAC prototype is also briefly discussed.     

Expert system application on preliminary design of water retaining structures

Design of liquid retaining structures involves many decisions to be made by the designer based on rules of thumb, heuristics, judgment, code of practice and previous experience. Various design parameters to be chosen include configuration, material, loading, etc. A novice engineer may face many difficulties in the design process. Recent developments in artificial intelligence and emerging field of knowledge-based system (KBS) have made widespread applications in different fields. However, no attempt has been made to apply this intelligent system to the design of liquid retaining structures. The objective of this study is, thus, to develop a KBS that has the ability to assist engineers in the preliminary design of liquid retaining structures. Moreover, it can provide expert advice to the user in selection of design criteria, design parameters and optimum configuration based on minimum cost. The development of a prototype KBS for the design of liquid retaining structures (LIQUID), using blackboard architecture with hybrid knowledge representation techniques including production rule system and object-oriented approach, is presented in this paper. An expert system shell, Visual Rule Studio, is employed to facilitate the development of this prototype system.     

Expert systems in engineering design: an application for injection molding of plastic parts

The rich development environments of expert system shells provide tools for developing knowledge-based expert systems for complex tasks such as engineering design. The diverse knowledge in engineering design combines heuristics with deterministic knowledge, from multiple sources, and involves complicated, interrelated components. The hybrid capabilities in emerging expert system tools effectively address this diverse knowledge, and facilitate the rapid development of design aids by the engineering designer. A prototype expert system for injection-molded plastic parts demonstrates the utility of expert systems for design applications. The prototype is implemented in an object-oriented, rule-based environment, and incorporates solid modeling software and external material databases.     

基于PAR 的排序算法自动生成研究

排序是计算机学科中的一类特殊问题,其算法设计策略的灵活性使得求解算法更具多样性.基于形式化方法PAR(partition-and-recur),研究了排序算法的自动生成问题.刻画了排序问题的代数性质,形式化构建了排序算法领域的泛型类型构件和算法构件,建立了排序领域特定语言和算法生成形式化模型,以参数替换的方式自动生成了一组排序算法,包括快速排序、堆排序、Shell排序等典型的已知算法以及增量选择排序等若干未见于现有文献的算法,并在程序生成系统中予以了实现.通过上层框架研究和底层构件支持,显著提高了特定领域算法的开发效率和可靠性.     

Knowledge-based system for collaborative process specification

This paper presents an ontology-based approach for the design of a collaborative business process model (CBP). This CBP is considered as a specification of needs in order to build a collaboration information system (CIS) for a network of organizations. The study is a part of a model-driven engineering approach of the CIS in a specific enterprise interoperability framework that will be summarised. An adaptation of the Business Process Modelling Notation (BPMN) is used to represent the CBP model. We develop a knowledge-based system (KbS) which is composed of three main parts: knowledge gathering, knowledge representation and reasoning, and collaborative business process modelling. The first part starts from a high abstraction level where knowledge from business partners is captured. A collaboration ontology is defined in order to provide a structure to store and use the knowledge captured. In parallel, we try to reuse generic existing knowledge about business processes from the MIT Process Handbook repository. This results in a collaboration process ontology that is also described. A set of rules is defined in order to extract knowledge about fragments of the CBP model from the two previous ontologies. These fragments are finally assembled in the third part of the KbS. A prototype of the KbS has been developed in order to implement and support this approach. The prototype is a computer-aided design tool of the CBP. In this paper, we will present the theoretical aspects of each part of this KbS as well as the tools that we developed and used in order to support its functionalities.     

Materialization and its metaclass implementation

Materialization is a powerful and ubiquitous abstraction pattern for conceptual modeling that relates a class of categories (e.g., models of cars) and a class of more concrete objects (e.g., individual cars). This paper presents materialization as a generic relationship between two classes of objects and describes an abstract implementation of it. The presentation is abstract in that it is not targeted at a specific object system. The target system is supposed to provide: 1) basic object-modeling facilities, supplemented with an explicit metaclass concept and 2) operations for dynamic schema evolution like creation or deletion of a subclass of a given class and modification of the type of an attribute of a class. The presentation is generic in that the semantics of materialization is implemented in a metaclass, which is a template to be instantiated in applications. Application classes are created as instances of the metaclass and they are thereby endowed with structure and behavior consistent with the generic semantics of materialization.     

Associative learning using similarity knowledge bases for relational database search

A knowledge-based interface system for relational databases is presented. The system consists of two basic components; a similarity knowledge base and a generalization reasoning engine. The knowledge base is a particular type of semantic network that represents similarity relationships between the data. The similarity relationships are derived from the relational database by a psychological model of similarity. The reasoning engine propagates information obtained from the user's responses over the similarity network and also determines the generic kind of question it should next pose to the user. Through this dialog process, the interface system aids the user in specifying requests for relevant data, as well as in retrieving data from the database. Following a presentation of the constructs that support database design, we note that agenda dependency of the dialog results will typically occur. A smoothing mechanism that can reduce this dependency is presented. Incorporation of smoothing in the database design improves the efficiency and the effectiveness of the resulting system.     

Libra: a high fidelity knowledge-based system for recommending scheduling programs

Contemporary knowledge systems are usually neither easy to use or understand. We propose a new class of knowledge systems, which we call high fidelity systems, that use representations and processes that closely resemble the objects and tasks with which people are already familiar. To illustrate the concept of high fidelity, we describe Libra, one such system for recommending scheduling programs. Our initial experience with Libra and its usage suggests that high fidelity not only enhances the user acceptability of knowledge-based systems, but it also facilities high speed design and implementation.We chose to replicate the knowledge in Libra because it is already published, and because we wanted to show that a Libra user can have an interface similar to the diagrams drawn in the journal paper. The latter was used to describe the knowledge-based framework for selecting scheduling systems. If we can replicate them in the user interface, we would have successfully created a high fidelity system — that is, the Libra user interface would be at least as able to communicate the framework to the user as the journal paper.     

基于形式语法的建筑设计细胞衍生法研究

目前可用的计算机辅助设计工具,为设计开发过程后期阶段提供了相当有效地支 持,但对于设计初始阶段,即设计思路成熟、但设计的结构和形状还未确定之时,需要一种新 的CAD 解决方案来支持设计者思维方式并激发创作灵感。因此,提出一种基于空间形式语法的 建筑设计生成方法,描述复杂空间形体如何自动派生--通过限定的规则产生初始体块,在规 则内生成与初始体块相似体块,再而改变局部可变规则生成多样复杂的系统,同时允许设计者 积极参与整个生成过程。以CFS 墙体原型建模为例,验证该参数化建模方法的有效性和可行性。