Rule-based Expert System Shell Research Articles

Alternatives to rules for knowledge-based modelling

The technology of knowledge-based systems undoubtedly offers potential for educational modelling, yet its practical impact on today's school classrooms is very limited. To an extent this is because the tools presently used in schools are mostly rule-based expert system shells, which lack usability. We developed three alternative tools, using ideas from knowledge acquisition research, and compared their effectiveness to that of an established rule-based shell. Children working with the new tools produced higher quality models and developed more positive attitudes. We relate these findings to the forms of representation provided by the new tools and present evidence that modelling increases children's representational skill. We conclude that knowledge acquisition systems and alternative forms of representation can contribute to improved forms of knowledge-based modelling.

F_MP: A fuzzy match framework for rule-based programming

Rule-based expert system shells have one important drawback in handling uncertain knowledge. It is the drawback that the style of their fuzzy reasoning process and their semantics both are not compatible with those of relational databases. On the other hand, production rule-based languages whose structure is similar to that of the databases fail to possess the fuzzy reasoning ability. Proposed in this paper is a framework to support a semantic based inexact match with Fuzzy Match Predicate (F_MP). In a uniform way it allows matches including fuzzy linguistic variables as well as fuzzy numbers. Our framework also adopts a design alternative to conform not only the semantics of its knowledge representation but also its reasoning style to those of the relational framework. It is a natural consequence that such a design alternative entails a seamless integration of our work into the relational databases. A major advantage of our framework is that it can be implemented on top of the production rule-based languages without modifying their discrimination networks. That is mainly due to the minimal semantic gap between the framework and the languages. In this paper, we demonstrate that: (1) F_MP is a uniform framework to provide the rule-based languages with fuzzy match facilities semantically enhanced, and that (2) its semantic conform well to that of the relational one. We also develop a rule-evaluation mechanism well suited to the aims.

A KNOWLEDGE BASED APPROACH TO ROCK MASS CLASSIFICATION AND TUNNEL SUPPORT SELECTION

Abstract This paper documents a knowledge based approach to rock mass classification and tunnel support selection. The particular rock mass classification system implemented in the developed knowledge based system, called Q-EXPERT, is the Q-system. The development of Q-EXPERT, using VP-Expert, a rule-based expert system shell, is documented in detail. Three cases on tunnel support reported in the literature are examined by Q-EXPERT and the results are compared with those actually used in the construction. Results of the case studies indicate that the developed prototype is able to reach recommendations comparable to those recommended by rock engineering experts.

Potato Insect Expert System: Computerized Approach to Insecticide Management for Colorado Potato Beetle (Coleoptera: Chrysomelidae)

The potato insect expert system (PIES) is a knowledge-based system for Colorado potato beetle, Leptinotarsa decemlineata (Say), management in commercial potato fields on the eastern shore of Virginia. PIES was written using VP-Expert, a rule-based expert system shell. The system uses insect life stage, potato growth stage, percentage of defoliation, and other factors to determine if an insecticide application is necessary to prevent tuber yield loss from Colorado potato beetle feeding. We compared recommendations from PIES with conventional spray thresholds based on the number of Colorado potato beetles per stem. Tuber yields were not significantly different between the 2 methods, although on average, PIES recommended 2.3 fewer insecticide applications than the conventional method. In addition, visual defoliation ratings for PIES required less time than conventional sampling for Colorado potato beetle on potato stems.

Refinement of the HEPAR expert system: tools and techniques

Methods and tools for the static and dynamic verification and validation of software systems are commonplace in the field of software engineering. In the field of expert systems, where it is more difficult to ensure that a system meets the specifications and expectations than in traditional software engineering, such tools are generally not available. In this paper, the need for more support of the development process by methods and tools is illustrated by the approach taken in building the HEPAR system, a rule-based expert system that can be used as a supportive tool in the diagnosis of disorders of the liver and biliary tract. At a certain stage in the development of this system an incremental development methodology has been adopted, in which implementation of parts of the expert system was followed by dynamic validation. For this purpose, a collection of software tools were implemented as extensions to a rule-based expert-system shell. These tools provide valuable information about the effects of modification of the HEPAR knowledge base, and indicate places in the knowledge base for refinement. It is believed that similar software tools may prove helpful in the development of other expert systems as well.

Expert Systems for Buildings—Case Studies of Design, Diagnosis, Contracts Interpretation

This paper describes the application of a rule-based expert system shell in three subdomains of building construction ie. building design synthesis, building defects diagnosis and building contract interpretation. This study is different in that all three applications were developed concurrently with the same tool in a collaborative effort by an expert system research team within the School of Building and Estate Management at the National University of Singapore. This research environment provides an unusual opportunity for comparing the effectiveness of rule-based knowledge representation against the domain characteristics of three different applications in building construction. This study, unlike most reviews on expert systems which highlight the differences among several shells, is able to cover the applicabilities and commonalities of one expert system shell against different problem areas.

Beginning computer-based modelling in primary schools

This paper describes an investigation of how children in primary schools can start to build their own models on a computer and what skills are inherent in this modelling process. The study focused on qualitative modelling using a rule-based expert system shell, Expert Builder, which made the knowledge structure and inference mechanism clearly visible to and manipulable by the user through a graphical user interface. The study was conducted within typical classroom contexts where pupils worked in groups on various activities. Towards the end of the study some of the pupils were able to structure and develop models without any help. An analysis of the pupils' activities was carried out using elements of learning taxonomies developed by Ennis, Kyllonen and Shute and Sternberg. A combination of the approaches of these three taxonomies enabled the clarification of specific modelling skills and general learning skills involved in modelling activities and provides one way of comparing modelling activities in terms of their component skills although it takes no account of the social interactions that also played an important part in the activities in this study. The national curriculum attainment target suggests that being able to build models on a computer is at attainment level 6 or 7 that is only likely to be reached by pupils over the age of 11. This study has shown that computer-based qualitative modelling can be successfully undertaken as collaborative group work by children aged 8–11.

Knowledge-based techniques for fault diagnosis of electrohydraulic drive systems

A rule-based expert system shell originally designed for consultative applications has been modified to operate on-line in conjunction with a fast data acquisition system. This paper considers some of the issues involved when considering leakage faults in a control valve/motor open-loop system. Consideration is given to establishing the knowledge base for steady-state operation of the hydraulic system.

Knowledge-based single machine scheduling

Production scheduling remains as one of the most important functions in manufacturing systems. Knowledge-based systems provide new insight to production scheduling. The increasing complexity of selecting the right procedure, understanding the procedure and solving an instant can be simplified with the help of knoweldge-based expert systems. This paper explains a prototype system developed using a rule-based expert system shell, M.1, for an application limited to single machine scheduling only.

Fuzzy concepts in an object oriented expert system shell

Fuzzy logic is one of the methods to model the vagueness and imprecision of human knowledge. Some rule-based expert system shells have been successfully developed and have demonstrated the power of fuzzy logic in dealing with inexact reasoning and rule inferences. However, using rules for knowledge representation is not structured enough. In addition, knowledge cannot be easily represented in an abstracted (hierarchical) from. In this article the introduction of fuzzy concepts into object oriented knowledge representation (OOKR), which is a structured knowledge representation scheme, is presented. A framework for handling all the possible fuzzy concepts in OOKR at both the dynamic and static levels is proposed. In order to handle the inheritance mechanism and to model the relations among classes, instances, and attributes, some new fuzzy concepts and operations are introduced. These concepts and operations are developed from the semantic meaning rather than by an ad hoc approach. A prototype of the expert system shell. System FX-I, has been successfully developed based on the above framework, showing the feasibility of handling inexact knowledge in a structural way.

PLAYMAKER: A KNOWLEDGE-BASED APPROACH TO CHARACTERIZING HYDROCARBON PLAYS

This paper discusses the design and implementation of PLAYMAKER, a knowledge-based system for characterizing hydrocarbon plays. PLAYMAKER is a component of XX (eXpert eXplorer), a workstation-based tool that aids exploration geologists in a number of different tasks: sediment and carbonate simulation, play and field characterization, retrieval and storage of information in a geological database, comparison of the play or field under study with other fields in the database, and report generation. PLAYMAKER is implemented using MIDST (Mixed Inferencing Dempster-Shafer Tool), a rule-based expert system shell that incorporates mixed-initiative and inexact reasoning based on the Dempster-Shafer evidence combination scheme. This paper discusses the effectiveness of a two-level knowledge base structure adopted for the design and implementation of PLAYMAKER.

Incorporation of AI and Expert Systems in Distributed Computer Control Systems

An object-oriented language is being developed as an extension to an existing rule-based expert system shell. The existing shell is embedded in a distributed control system. Being embedded, it reduces hardware cost and communication bottlenecks. Object orientation dramatically increases the expressability of the language. The shell handles the procedural programming tasks so the knowledge base developer does not need to. The use of the language is demonstrated for an oil movement expert system. Objects describe the physical plant. Objects also describe aore abstract entities such as potential routes of oil through the pipes of the physical plant. A search method is used to generate potential routings and to recommend the good ones. The language is designed to be natural so that a process, instrumentation, operations, or plant management expert can develop an expert system. directly without either learning advanced programming skills or requiring the services of a "knowledge engineer."

Screening financial innovations: an expert system approach

An expert system, called Innovator, that helps a financial-service organization (FSO) evaluate new products it does not currently offer is described. Innovator was implemented using a rule-based expert system shell called Expert System Environment. The authors examine why FSOs need expert systems for screening financial innovations. The knowledge-representation and implementation details, and the system validation process are described. Innovator's benefits and continuing research are discussed. >

Expert systems applications in computer-aided design

Rule-based expert system shells are demonstrated to be useful in elementary design decision making. Two applications are presented which utilise the BUILD shell. The first is concerned with the selection and design of earth-retaining structures and makes use of passive graphics in descriptions. The second is concerned with the analysis and synthesis of kitchens and uses graphics to allow the user to interact with the system. Such systems are useful when the range of options is small.