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1.
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.  相似文献   

2.
In recent years, design patterns gain more interest in software engineering communities for both software development and maintenance. As a template to solve a certain recurring problem, a design pattern documents successful experiences of software experts and gradually becomes the design guidelines of software development. Applying design patterns correctly can improve the efficiency of software design in terms of reusability and enhance maintainability during reverse engineering. Software can be evolved when developers modify their initial designs as requirements change. For instance, a developer may add/delete a set of design elements, such as classes and methods. Modifications on software artifacts can introduce conflicts and inconsistencies in the previously applied design patterns, which are difficult to find and time-consuming to correct. This paper presents a graph-transformation approach to pattern level design validation and evolution. Based on a well founded formalism, we validate a given design by a graph grammar parser and automatically evolve the design at pattern level using a graph-transformation system. Rules for potential pattern evolutions are predefined. The graph-transformation approach preserves the integrity and consistency of design patterns in the system when designs change. A prototype system is built and a case study on the Strategy pattern demonstrates the feasibility of pattern-based design validation and evolution using graph transformation techniques.  相似文献   

3.
This paper describes the work undertaken, at the Higher Technical School of Industrial Engineers of Gijón, for the development of computer aided systems, in the line of expert systems, concentrating research, and development in the field of mechanical design. We are using this software as an integrated tool in our work for teaching machine design. Models to develop the software of several components are defined, and their application methodology is also presented.

An application which tackles the problem of configuration design, applied to mechanical transmission is also described in this article. The failure of machine elements in mechanical design, frequently occurs due to poorly detailed projects.

The developed work is applied to the design of configurations for mechanical systems, by means of an intelligent program which incorporates the process of geometric design, the calculation of mechanical elements, the selection in electronic databases and the output of CAD plans.

Configuration design is a type of design problem where the different elements (which make up the system, mechanism or machine project object), are selected from databases and connected in order to complete the requirements (functionality, specifications, and established restrictions) outlined in the problem.  相似文献   


4.
设计模式描述了在软件开发过程中经常出现的问题及其解决方案,是软件复用的有效途径。文章详细地分析了设计摸式中的Factory模式、Observer模式、Bridge模式在SDH网管软件开发中的应用,证明了在SDH网管系统中运用设计模式能够有效地提高系统质量、优化系统结构。  相似文献   

5.
Abstract: The design of liquid‐retaining structures involves many decisions to be made by the designer based on rules of thumb, heuristics, judgement, codes of practice and previous experience. Structural design problems are often ill structured and there is a need to develop programming environments that can incorporate engineering judgement along with algorithmic tools. Recent developments in artificial intelligence have made it possible to develop an expert system that can provide expert advice to the user in the selection of design criteria and design parameters. This paper introduces the development of an expert system in the design of liquid‐retaining structures using blackboard architecture. An expert system shell, Visual Rule Studio, is employed to facilitate the development of this prototype system. It is a coupled system combining symbolic processing with traditional numerical processing. The expert system developed is based on British Standards Code of Practice BS8007. Explanations are made to assist inexperienced designers or civil engineering students to learn how to design liquid‐retaining structures effectively and sustainably in their design practices. The use of this expert system in disseminating heuristic knowledge and experience to practitioners and engineering students is discussed.  相似文献   

6.
Uwe Zdun 《Software》2007,37(9):983-1016
Software patterns provide reusable solutions to recurring design problems in a particular context. The software architect or designer must find the relevant patterns and pattern languages that need to be considered, and select the appropriate patterns, as well as the best order to apply them. If the patterns and pattern languages are written by multiple pattern authors, it might be necessary to identify interdependencies and overlaps between these patterns and pattern languages first. Out of the possible multitude of patterns and pattern combinations that might provide a solution to a particular design problem, one fitting solution must be selected. This can only be mastered with a sufficient expertise for both the relevant patterns and the domain in which they are applied. To remedy these issues we provide an approach to support the selection of patterns based on desired quality attributes and systematic design decisions based on patterns. We propose to formalize the pattern relationships in a pattern language grammar and to annotate the grammar with effects on quality goals. In a second step, complex design decisions are analyzed further using the design spaces covered by a set of related software patterns. This approach helps to systematically find and categorize the appropriate software patterns—possibly even from different sources. As a case study of our approach, we analyze patterns from a pattern language for distributed object middleware. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

7.
This paper addresses the problem of how to develop an expert system that is able to design or to assist in the design of a control system. The discussion includes how to structure the expert system, how to choose the relationship between the symbolic and numerical processor and how to divide the work among the expert system, the computer aided control systems analysis package and the design engineer. A prototype intelligent design associated is presented and an example of a compensator design is given.  相似文献   

8.
The development of four separate, prototype expert systems to aid in software engineering management is described. Given the values for certain metrics, these systems provide interpretations which explain any abnormal patterns of these values during the development of a software project. The four expert systems which solve the same problem, were built using two different approaches to knowledge acquisition, a bottom-up approach and a top-down approach and two different expert system methods, rule-based deduction and frame-based abduction. In a comparison to see which methods might better suit the needs of this field, it was found that the bottom-up approach led to better results that did the top-down approach, and the rule-based deduction systems using simple rules provided more complete and correct solutions than did the frame-based abduction systems  相似文献   

9.
Over many years of research and practices in software development, hundreds of software design patterns have been invented and published. Now, a question which naturally arises is how software developers select the right design patterns from all relevant patterns to solve design problems in the software design phase. To address this issue, in this paper, we propose a two-phase method to select a right design pattern. The proposed method is based on a text classification approach that aims to show an appropriate way to suggest the right design pattern(s) to developers for solving each given design problem. There are two advantages of the proposed method in comparison to previous works. First, there is no need for semi-formal specifications of design patterns and second, the suitable design patterns are suggested with their degree of similarity to the design problem. To evaluate the proposed method, we apply it on real problems and several case studies. The experimental results show that the proposed method is promising and effective.  相似文献   

10.
ContextNumerous software design patterns have been introduced and cataloged either as a canonical or a variant solution to solve a design problem. The existing automatic techniques for design pattern(s) selection aid novice software developers to select the more appropriate design pattern(s) from the list of applicable patterns to solve a design problem in the designing phase of software development life cycle.GoalHowever, the existing automatic techniques are limited to the semi-formal specification, multi-class problem, an adequate sample size to make precise learning and individual classifier training in order to determine a candidate design pattern class and suggest more appropriate pattern(s).MethodTo address these issues, we exploit a text categorization based approach via Fuzzy c-means (unsupervised learning technique) that targets to present a systematic way to group the similar design patterns and suggest the appropriate design pattern(s) to developers related to the specification of a given design problem. We also propose an evaluation model to assess the effectiveness of the proposed approach in the context of several real design problems and design pattern collections. Subsequently, we also propose a new feature selection method Ensemble-IG to overcome the multi-class problem and improve the classification performance of the proposed approach.ResultsThe promising experimental results suggest the applicability of the proposed approach in the domain of classification and selection of appropriate design patterns. Subsequently, we also observed the significant improvement in learning precision of the proposed approach through Ensemble-IG.ConclusionThe proposed approach has four advantages as compared to previous work. First, the semi-formal specification of design patterns is not required as a prerequisite; second, the ground reality of class label assignment is not mandatory; third, lack of classifier’s training for each design pattern class and fourth, an adequate sample size is not required to make precise learning.  相似文献   

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13.
甘蔗收获机械可视化虚拟设计平台的研究开发   总被引:1,自引:2,他引:1  
介绍了甘蔗收获机械可视化虚拟集成设计平台研究开发的基本思路。该平台的构建通过STEP标准建立产品开发的全局共享信息模型,利用PDM软件集成和封装CAD/CAE及其它产品设计过程中用到的应用软件;平台也集成了甘蔗收获机械设计、分析和评价专家系统,专家系统采用模糊评价的方法对开发过程设计和仿真分析的结果进行评价和决策。集成平台支持甘蔗收获机械可视化虚拟产品集成化的团队设计及收获机械系列化产品开发。  相似文献   

14.
超图模型:基于超图的设计模式描述和复用实现   总被引:5,自引:0,他引:5  
设计模式描述了面向对象软件设计的经验,是软件复用的关键技术。由于设计模式涉及范围广泛而且抽象,即使模式本身并不深奥,因其表示或描述隐晦,在软件开发中难以理解和实现复用。文章提出了超图模型,即基于超图的设计模式表示,并对其在软件系统开发中的复用进行了分析研究。对基于设计模式的软件系统构建进行了探索。  相似文献   

15.
基于LePUS的设计模式CASE工具的设计与实现   总被引:1,自引:0,他引:1  
蔡亮  袁捷  周洪亮 《计算机工程与设计》2004,25(11):2074-2076,2084
设计模式是软件工程界的热点,在面向对象软件设计中扮演着重要角色,自动化支持设计模式非常必要。为此,以LePUS语言为基础,提出了一个支持设计模式的CASE工具原型模型,该工具支持设计模式代码框架的自动生成,更重要的是该工具可以通过加入新的设计模式而得以扩展。此外,详细分析了实现中的源程序内部表示、设计模式实例化、动态模板生成技术等关键技术。  相似文献   

16.
Abstract: This paper describes a project undertaken in the Department of Information and Library Studies at Loughborough University to develop a prototype expert system to assist with the selection of online business databases for British company information. The project was funded by the British Library Research and Development Department for 21 months, commencing July 1990. Specific phases of the project comprised a literature survey, knowledge acquisition involving experts in online searching, the design and development of a system called CIDA (Company Information Database Adviser) which was some 4Mb in size, and a user evaluation of this prototype. The study demonstrated that expertise in business database selection can successfully be distilled into a number of rules which can be applied by an expert system.  相似文献   

17.
This research investigates the use of patterns in designing adaptable, flexible hypermedia applications. While patterns are particularly applicable to software design, they can also be used to assist designers of other types of applications. We have developed a method (APHID) that guides a hypermedia creator through the analysis and design process. The method ensures that good design principles are followed, both for the hypermedia application and for the interface that presents the hypermedia application. Our method uses a concept map, constraints, and patterns (instructional and presentation) to support partial automation for creating hypermedia applications. We also present a prototype software system that uses the APHID method to create instructional hypermedia applications semi-automatically. The applications created using APHID are tailored to specific types of learners. We conclude with a claim that this approach is applicable not just to instructional hypermedia, but to the larger problem of generating adaptable interfaces.  相似文献   

18.
设计模式在面向对象软件开发领域中得到了广泛的应用,增强了代码的重用性、灵活性和模块化,提高了系统开发的效率。成功运用设计模式的关键在于系统设计者能够准确地理解应用场景和预测使用模式后产生的效果。文章通过在一个3G综合业务管理平台中引入设计模式,阐述了Filter模式、Adapter模式在综合业务管理系统中的应用。  相似文献   

19.
设计模式是人们在实践过程中总结出来的成功设计范例,它的正确选择和使用是发挥模式作用的关键。而改变在设计模式应用过程中过分依靠人工的现状,有着重大的意义。重新应用需求和设计模式的形式化描述,在模式库中找出一组包含新应用领域的模式的可重用的设计以及重用模式的变换适配等方面,详细讨论了一种软件设计模式的自动选择方法。并结合实例给出了这种方法在网上证券交易原型系统中的实现。该方法为设计模式的重用提供了一个有效的途径,形式化描述是其基础,设计模式的组织和检索是其核心。利用此方法选择设计模式,可大大提高模式重用的准确性和软件开发的效率。  相似文献   

20.
SEIS++:一个油气勘探领域软件建造和集成的模式语言   总被引:1,自引:0,他引:1  
工业化的软件复用从通用类库进化到了面向领域的应用框架和设计模式,与框架相比,设计模式更集中于软件体系结构中重复出现的设计韵律,它主要由可复用的抽象设计结构组成,特定领域内一组相关的设计模式构成了该领域的模式语言,它们可在领域内重复使用以完成某类特定系统的体系结构设计。  相似文献   

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