Knowledge Acquisition for Bridge Design Expert Systems

Abstract: Knowledge acquisition for developing design knowledge bases is difficult and time consuming. In this paper, a new approach for acquiring design knowledge is presented. The object-oriented approach is applied to model the design objects and the design process. It is discussed that in the case of routine bridge design, synthesis of the bridge structure can be achieved through recursive top-down refinement using selection among predefined types, and decomposition of the structure into predefined components. Having this design model, a methodology for using analogy to augment the knowledge base is proposed. Analogy can be used to retrieve and modib an available design object in order to create a similar object interactively. A prototype system that implements this methodology is presented.     

Interfacing Data Bases With Expert Systems: A Retaining Wall Management Application

This paper presents the development of an interface between an expert system and a data base management system. The flexibility provided by such interface is shown to be very useful for civil engineering applications. An example application is developed in this paper that applies this interface to the management of retaining walls. The different relational data bases store most of the required information. The inventory data base stores identification information, the inspection data base stores historical condition data gathered by inspections, and the replacement data base stores information needed to perform a replacement cost analysis for a retaining wall. The expert system, on the other hand, is used to diagnose the possible reasons for the failure of a retaining wall. The development of the data base management system, the expert system, and the interface between them is discussed, along with the restrictions imposed by the software chosen for this example application.     

基于专家知识的结构性能评估

专家知识在结构性能评估中占有重要地位。本文在充分利用专家知识的基础上，建议了三种结构性能评估方法：加权平均法、模糊综合评判法和广义量化法。这些方法都从一定程度上消除了由于每个专家知识、水平、洞察力及考虑问题的侧重面不同等主观因素对评估结果的不利影响，所得结论较符合工程实际。     

Expert Systems for the Interpretation of River Quality Data

Sample data on river quality are used for a variety of management purposes. The paper considers the role of expert systems in interpreting such data. An example is given of a prototype rule-based system designed to aid in assessing compliance with European Community (EC) Directives. It is suggested that, although this type of formal characterization is a necessary part of management, it provides poor information for decision making. The development of an expert system to provide a more accurate and informative interpretation of episodic pollution events is then described. The paper concludes by discussing the practical application of these approaches.     

A Relational Database Interface for Design Expert Systems

Most of the software so far developed that is based on expert systems uses a rule-based representation of the domain knowledge. Expert System applications in the engineering design process, however, frequently require access to a large static knowledge base that is easily represented in a database. This article presents the details of a relational database module to represent such static knowledge that is callable as a function by a rule-based expert system. The software implemented on a microcomputer using a C compiler, can be accessed by any inference engine with external C function calling capability. It has been used in developing an expert system for the design of steel structural elements.     

Expert Systems,Local Knowledge and Power in Argyll,Scotland

This article is based on research carried out as part of a larger project into land use and landscape in Argyll 1945–2005. The aim of the article is to point out the ways in which strategies employed by agencies responsible for monitoring rural landscapes interact with the ideas and knowledge of local people. It will provide evidence from field work in the region to demonstrate that, firstly, the programmes employed and enforced by national agencies are shaped by a particular understanding of environmental history, and secondly, that the interaction with rural labourers and farmers is weak, leading to a neglect of information and support which might otherwise make these programmes far more effective.     

浮法玻璃退火窑故障诊断专家系统设计

开发了一种浮法玻璃退火窑故障诊断专家系统,能有效解决目前浮法玻璃退火窑故障诊断随意性和滞后性的问题.该系统采用Visual C 语言编写,增强了用户界面的友好性,便于用户在较短时间内迅速掌握此系统的运用.编写过程中采用了实例推理机制,提高了结论的可靠性及运行速度.     

CONCEPTUAL: An Expert System for Conceptual Structural Design

In the conceptual design stage of a building the number of possible building configurations is enormous. The building systems selected in this stage affect the building cost much more than any other decision made in the subsequent design stages. Currently designers base their decisions mostly on experience and intuition. Since this process is not algorithmic, the best possible design is not guaranteed. In this article a model of the process by which a human expert arrives at a conceptual design for a building is presented. Based on this model, CONCEPTUAL, an automated knowledge-based expert system has been developed by the authors to aid in the conceptual design stage of buildings.     

Integrated Information Management Expert System For Structural Engineering of Buildings

Abstract: This paper describes the development of an integrated Information Management expert system (IMXpert) which enables structural engineers or architects to produce results of high quality within a short time in works related to the structural engineering of buildings. IMXpert gives various data or functions according to the user's request. The study can be divided into problem analysis and system design. For the systematic representation of building structure and the structural design process, an object-oriented design method has been used for the problem analysis. Various types of structural components and operations closely related to them have been extracted and defined as independent objects. The complete building structure and structural design process can be represented by combining these objects and operations. A centralized database has been designed for the consistent and integrated management of object instances.     

Computational Spring Systems: Open Design Processes for Complex Structural Systems

Sean Ahlquist and Moritz Fleischmann are both former graduates of the Emergent Technologies and Design Programme at the Architectural Association (AA) in London, who have now established their own innovative research and design practice, morse. Here they describe their work with computational spring algorithms that has enabled iterative investigations of tension active systems and structures. Copyright © 2009 John Wiley & Sons, Ltd.     

Algorithms for Optimal Design of Smart Structural Systems

Simultaneous optimal design of smart structural systems is considered in this article. A major augmentation to this multidisciplinary optimization problem is optimal structural layout design in terms of shape and topology. Four algorithms, namely, guided random search techniques, sequential mathematical programming, and their mixtures, are presented and used for the problem solving. A method to prevent singularities when updating structural layout is also suggested. Design variable linking schemes are used to reduce the number of design variables and give reasonable optimal results. Two examples are solved. Comparison of the algorithms on the basis of achieved improvements in system energy, control effort, robustness, and controllability is made.     

Extending Prolog to Provide Better Support for Design Code Expert Systems

The CSIR0³ Division of Building Research (DBR) has built a number of text-based and graphics-based design code expert systems in PROLOG. Each of these systems involves several thousand lines of PROLOG and stretches to the limit and the capacity of the IBM ATs on which they run. We have found PROLOG to be a very powerful language for expressing the complex rules and relationships found in building design codes and related applications. Nevertheless, it has a number of weaknesses, particularly in expressing procedural knowledge and arithmetic relationships, and in implementing complex tables and user interfaces. We have designed and implemented extensions to PROLOG to overcome these difficulties. These include new built-in functions to perform functions that are difficult to code in PROLOG, an easy way to add further built-in functions, a meta-interpreter to keep track of intermediate results, sets of routines to support user input and explanation, and a definite clause grammar to implement a more syntactically pleasant language for writing rules. These extensions are being used to develop a larger and much more complete version of the WINDLOADER expert system, and have greatly facilitated this task.     

A Data Preprocessor for Structural Analysis and Design Programs

An interactive program for computer-aided data management for structural analysis and design programs has been developed. The program provides the ability to create, store, retrieve, and update data files and display the configuration for 2-D and 3-D skeletal structures. The unique features of the program include: (1) interactive data entry scheme, (2) full-screen data management ability with full cursor control, (3) highlighted single key stroke commands, (4) continuous display of editor commands, (5) well designed screen layout for data entry and management, (6) extensive on-line prompts, (7) extensive checking of invalid input type, (8) fast scrolling through each screen of data, and (9) ability to display the structure configuration.
The program written in turbopascal, may be used with any microcomputer which uses PC-DOS and requires 96 Kb user memory. An ISM-PC color graphics (or equivalent) or monochrome systems may be used.     

海淀温泉球类综合馆结构设计

对于要求空旷空间且该空间包括不同层交错的体育馆建筑,在方案设计时应与建筑专业密切配合,使结构选型更合理且能充分体现建筑及使用者的要求.本文介绍了体育馆的ETABS计算结果和设计要点以及楼梯抗震分析要点.     

数据挖掘技术在基坑设计专家系统中的应用

本文在介绍工程数据挖掘的概念、功能及逻辑结构的基础上,结合本地区典型基坑勘察设计资料,提出了将人工神经网络用于基坑设计专家系统的方法和步骤。应用表明,人工神经网络建立的模型,能将多方面的影响因素与设计方案之间的非线性关系描述出来,通过检验样本的预测证明这一方法是可行的,具有广泛的应用前景。     

Uncertainty Methods in Expert Systems

The paper introduces the main measures of uncertainty and discusses some of the problems associated with conventional uncertainty propagation methods, such as those based on independent probabilities and the methods used with certainty factors, belief, and possibility functions. Some examples show the importance of the associated errors. Alternative methods, such as log-linear regression and causal networks or influence diagram models, are discussed. Finally, their structural and parametric learning possibilities are analyzed.     

Uncertainty Measures in Expert Systems

Abstract: In classic logic, premises, conclusions, and rules are treated deterministically, i.e., they are considered as either true or false. However, when dealing with reality, one finds that all these elements must be considered as uncertain. Thus classic logic must be extended to cover real situations. One possible extension is given by uncertainty measures together with aggregation formulas that combine the uncertainty of premises with that of the rules to obtain the uncertainty of conclusions. This paper describes different uncertainty measures, giving the physical meaning of the implied axioms and their limitations, illustrated by some examples. Finally, a classification of some of the well-known uncertainty measures, such as belief and plausibility functions, probabilities, necessities, and possibilities, is given.     

Log-Linear Models in Expert Systems

Abstract: The paper describes how log-linear models can be used to deal with uncertainty in expert systems, avoiding the common problems of many probability-based expert systems. After a general introduction to log-linear models, including hierarchical models, maximum likelihood estimation for poissonian and multinomial sampling is described and parametric and structural learning methods are illustrated by simple examples. Finally, a traffic engineering example is given.     

Linear Programming and Expert Systems

Abstract: This paper describes an expert system shell based on linear programming. The knowledge base consists of the parametric equations of the feasible set, which is obtained from upper and lower bounds of probabilities of given sets. The inference engine consists of an algorithm that gives the parametric equations of the feasible set and works in an incremental manner; any previously calculated feasible set is modified when new information becomes available, using all previous calculations. This allows for rapid updating of the knowledge base and permits a very quick solution of the optimization problems (finding of lower and upper bounds of the probability of any set) to be obtained. Finally, three civil engineering examples are included.     

智能建筑系统集成的设计与实现

在科学技术的推动下,我国智能建筑的发展速度越来越快。智能建筑的发展不能只关注外部的美观,更应通过计算机技术对建筑进行智能化管理,这样才能为人们提供一个健康舒适安全的生活环境。在智能建筑系统集成中首要内容就是要建立一个完善的IBMS集成平台。