Object-oriented Expert System Research Articles

Understanding ATLAS infrastructure behaviour with an Expert System

The ATLAS detector requires a huge infrastructure consisting of numerous interconnected systems forming a complex mesh which undergoes constant maintenance and upgrades. The ATLAS Technical Coordination Expert System provides, by the means of a user interface, a quick and deep understanding of the infrastructure, which helps to plan interventions by foreseeing unexpected consequences, and to understand complex events when time is crucial in the ATLAS control room. It is an object-oriented expert system based on the knowledge composed of inference rules and information from diverse domains such as detector control and safety systems, gas, water, cooling, ventilation, cryogenics, and electricity distribution. This paper discusses the latest developments in the inference engine and the implementation of the most probable cause algorithm based on them. One example from the annual maintenance of the 15°C water circuit chillers is discussed.

ExSIDE: Component Based Object Oriented Expert System’s Integrated Development Environment

This paper describes the design and development of a component-based object oriented Expert System's Integrated Development Environment (ExSIDE). It is integrated with (i) a user-friendly manual and automated knowledge acquisition and management tool (ExSIDE_KAMT);(ii) an independent and customizable runtime module (ExSIDE_RTM); (iii) an object-oriented in-process Component Object Model (COM)-based inference engine (ExSIDE_IE); (iv) an object-oriented out-of-process COM-based inference engine (ExSIDE_IESvr); (v) and a PHP based inference engine (ExSIDE_PHP). ExSIDE_RTM can function independently as an Expert System Shell (ESS) and helps user to develop Expert Systems rapidly. ExSIDE_IE and ExSIDE_IES can be integrated with COM-supporting general purpose and scientific application development tools such as variants of C/C++/C#, BASIC (Visual BASIC®, REALbasic®), Java, MATLAB®, LabVIEW®, and Mathematica® to develop more advanced Expert Systems. Finally, ExSIDE_IE and ExSIDE_PHP can be used with Active Server Pages (ASP) and PHP technologies to generate web based Expert Systems. The unique framework of the ExSIDE enables rapid development of Expert Systems' on PC and web for technical and non-technical users. The overall system was developed successfully, and its usability was demonstrated via five unique Expert Systems case studies discussed in this paper.

Development of a rule-based diagnostic platform on an object-oriented expert system shell

This paper presents the development and implementation of a real-time rule-based diagnostic platform. The knowledge is acquired from domain experts and textbooks and the design of the fault diagnosis expert system was performed in the following ways: (i) establishing of corresponding classes and instances to build the domain map, (ii) creating of generic fault models based on events, and (iii) building of diagnostic reasoning based on rules.Knowledge representation is a complicated issue of expert systems. One highlight of this paper is that the Multilevel Flow Model has been used to represent the knowledge, which composes the domain map within the expert system as well as providing a concise description of the system.The developed platform is illustrated using the pressure safety system of a pressurized water reactor as an example of the simulation test bed; the platform is developed using the commercial and industrially validated software G2. The emulation test was conducted and it has been proven that the fault diagnosis expert system can identify the faults correctly and in a timely way; this system can be used as a simulation-based training tool to assist operators to make better decisions.

Fuzzy Concurrent Object Oriented Expert System for Fault Diagnosis in 8085 Microprocessor Based System Board

With the acceptance of artificial intelligence paradigm, a number of successful artificial intelligence systems were created. Fault diagnosis in microprocessor based boards needs lot of empirical knowledge and expertise and is a true artificial intelligence problem. Research on fault diagnosis in microprocessor based system boards using new fuzzy-object oriented approach is presented in this paper. There are many uncertain situations observed during fault diagnosis. These uncertain situations were handled using fuzzy mathematics properties. Fuzzy inference mechanism is demonstrated using one case study. Some typical faults in 8085 microprocessor board and diagnostic procedures used is presented in this paper.

A Novel Approach for Troubleshooting Microprocessor based Systems using An Object Oriented Expert System

The paper presents an object oriented fault diagnostic expert system framework which analyses observations from the unit under test when fault occurs and infers the causes of failures. The frame work is characterized by two basic features. The first includes a fault diagnostic strategy which utilizes the fault classification and checks knowledge about unit under test. The fault classification knowledge reduces the complexity in fault diagnosis by partitioning the fault section. The second characteristic is object oriented inference mechanism using backward chaining with message passing within objects. The refractoriness and recency property of inference mechanism improve efficiency in fault diagnosis. The developed framework demonstrates its effectiveness and superiority compared to earlier approaches

Concurrent Object-Oriented Expert System Framework for Fault Diagnosis in the Microprocessor based System

The paper presents a concurrent fault diagnostic expert system framework. The framework is characterised by two basic features. The first includes a concurrent fault diagnostic strategy, which utilises fault isolation and diagnostic knowledge about unit under test. The second characteristic is object-oriented inference mechanism using simultaneous message passing using multithreading. Object orientation in inference mechanism has improved inference efficiency. The degree of accuracy to which faults are located is improved using fault isolation knowledge. The developed framework is evaluated for its effectiveness and superiority compared with earlier approaches using case studies.

TEAPEST: AN EXPERT SYSTEM FOR INSECT PEST MANAGEMENT IN TEA

Tea is one of the major crops of India and is grown over a large area. The loss of crop due to insects is one of theproductivity barriers. Insect pest management is a challenging problem to tea cultivators. Proper identification of the insectpests, selection of chemical pesticides and their discriminate use, need human expertise, experience, and judgment. But,sufficient number of competent human experts are not available to cover the large area. To mitigate the lack of humanexpertise and assist the existing experts for improved decisionmaking, an expert system for insect pest management wouldbe useful. This article presents a rulebased, objectoriented expert system for insect pest management in tea code namedTEAPEST. The system identifies major insect pests of tea and suggests appropriate control measures. TEAPEST showsgood performance as evident from its performance evaluation.

A knowledge‐based approach to maintenance project planning

Maintenance issues comprise an important, though frequently overlooked, area of manufacturing operations. In smaller companies in particular, expertise for effective maintenance project planning may be lacking. In this paper we discuss the development of an object‐oriented expert system to support such project planning. The system was developed to meet the needs of an automotive components manufacturer, and focuses solely on its material‐handling‐oriented projects. The microcomputer‐based expert system considers issues of schedule, inventory availability and cost.

Object-oriented methods drive protective relay system

China is a developing country, and shortages in electrical power supply exist in most provincial power systems. Stability margins are always very limited, which requires operators to run the system carefully. With each change in either the power system configuration or operating conditions, a series of actions must be taken to guarantee the safety of the power system. The actions adopted for the protective relays include arranging protective devices appropriately and setting relays at their appropriate values for all elements involved. In addition, as power systems are developing very fast in China, the number of skilled operators available is far less than required. Expert systems are urgently needed. This article describes the use of object-oriented (OO) methods to develop expert systems and, in particular, features the object-oriented expert system for the power system protective relay operation and management (OOPRES). The article covers knowledge acquisition and representation, knowledge management, and inference engine.

A feature-based object-oriented expert system to model and support product design

In this paper a computer program to model and support product design is presented. The product is represented through a hierarchical structure that allows the user to navigate across the product’s components, and it aims at facilitating each step of the detail design process. A graphical interface was also developed, which shows visually to the user the contents of the product structure. Features are used as building blocks for the parts that compose the product, and object-oriented methodology was used as a means to implement the product structure. Finally, an expert system was also implemented, whose knowledge base rules help the user design a product that meets design and manufacturing requirements.

A Web-based multi-agent system for interpreting medical images

A difficult problem in medical image interpretation is that for every image type such as x-ray and every body organ such as heart, there exist specific solutions that do not allow for generalization. Just collecting all the specific solutions will not achieve the vision of a computerized physician. To address this problem, we develop an intelligent agent approach based on the concept of active fusion and agent-oriented programming. The advantage of agent-oriented programming is that it combines the benefits of object-oriented programming and expert system. Following this approach, we develop a Web-based multi-agent system for interpreting medical images. The system is composed of two major types of intelligent agents: radiologist agents and patient representative agents. A radiologist agent decomposes the image interpretation task into smaller subtasks, uses multiple agents to solve the subtasks, and combines the solutions to the subtasks intelligently to solve the image interpretation problem. A patient representative agent takes questions from the user (usually a patient) through a Web-based interface, asks for multiple opinions from radiologist agents in interpreting a given set of images, and then integrates the opinions for the user. In addition, a patient representative agent can answer questions based on the information in a medical information database. To maximize the satisfaction that patients receive, the patient representative agents must be as informative and timely as communicating with a human. With an efficient pseudo-natural language processing, a knowledge base in XML, and user communication through Microsoft Agent, the patient representative agents can answer questions effectively.

Knowledge acquisition and knowledge representation with class: the object-oriented paradigm

Knowledge acquisition and knowledge representation are the fundamental building blocks of knowledge-based systems (KBSs). How to efficiently elicit knowledge from experts and transform this elicited knowledge into a machine usable format is a significant and time consuming problem for KBS developers. Object-orientation provides several solutions to persistent knowledge acquisition and knowledge representation problems including transportability, knowledge reuse, and knowledge growth. An automated graphical knowledge acquisition tool is presented, based upon object-oriented principles. The object-oriented graphical interface provides a modeling platform that is easily understood by experts and knowledge engineers. The object-oriented base for the automated KA tool provides a representation independent methodology that can easily be mapped into any other object-oriented expert system or other object-oriented intelligent tools.

AN EXPERT SYSTEM FOR SOIL TAXONOMY

This study tested the feasibility of producing an automated expert system for Soil Taxonomy to identify soil order from stored data by building an expert system prototype. Soil Taxonomy rules for the Histosol, Spodosol, Andisol, and Oxisol orders were translated into decision tree format. Seventy independent properties were stored in tabular format for each pedon. Heuristic knowledge (expert rules) was added to the decision trees to query a minimum data set, with 13 field description properties required to contain data for each soil horizon, 20 default values, and three estimated values from lookup tables. The prototype expert system was developed using an object-oriented expert system shell. Twenty-seven subsections were named in the rules to identify the Histosol, Spodosol, Andisol, and Oxisol soil orders. Sixty-seven objects, 70 independent properties, and 135 calculated properties were needed to define these subsections and their properties. The tested prototype quickly and correctly identified the diagnostic horizons, nonspatial differentiae, and the soil order, proving the feasibility of developing an expert system for Soil Taxonomy using existing computer programs and programming methods. We recommend improvements in policy and procedure for recording field description data and development of the expert rules to add dynamic links to outside models and software and incorporate fuzzy logic. The project should be continued to improve the prototype interface and data output features and to complete an expert system to add the remaining soil orders for Soil Taxonomy.

A FUNCTIONAL ANALYSIS OF SOIL TAXONOMY IN RELATION TO EXPERT SYSTEM TECHNIQUES

The characteristics of Soil Taxonomy are analyzed relative to various techniques for developing expert systems. Special emphasis is placed on computer program features that allow for more consistent application of classification systems and make them more user-friendly and understandable. We studied the functional logic and query processes employed by Soil Taxonomy to identify soil individuals and compared the methods with those used in other natural object classification systems. Numerical and classical identification methods and program features found in recent computer programs were evaluated for use with Soil Taxonomy. The keys in Soil Taxonomy are purely phenetic in nature and single-access in approach. In the absence of rule- and value confidence-weighting factors, the rules must be encoded without sequence modification to preserve the decision logic. Decisions in Soil Taxonomy query a large, often incomplete, and sometimes faulty data set, requiring error-checking of data and the addition of expert rules to the encoded decisions to prevent indecision. Soil Taxonomy rules check within the soil individual for the presence or absence of spatial and nonspatial differentiae, specific property values, or other qualifications. Soil Taxonomy is suitable as the subject of an object-oriented expert system, and planning has begun on development of an automated prototype for the Histosol, Andisol, Spodosol, and Oxisol soil orders. Expert system features coupled with additional models and algorithms can be used to improve the use and user-friendliness of Soil Taxonomy.

Optimal operation grouping and sequencing technique for multistage machining systems

In this study, the problem of determining the optimal group and sequence of operations for a multistage machining system is investigated. A method incorporating a combination of the expert system and mathematical programming is proposed to produce an optimal operation sequence minimizing the noncutting time. Also precedence, tolerance and alternative operations are taken into consideration as constraints. The mathematical method performs grouping and sequencing simultaneously and the expert system preprocesses the procedure by eliminating infeasible solution sets and clustering the operations according to the tool commonalities. A prototype CAPP system is also developed using an objectoriented expert system shell. The system not only performs local process planning for each machining feature of the part but also analyses the relationships among operations to generate a global process plan. The advantage and effectiveness of the proposed approach are verified through an example of an actual manufacturing product.

A process plant simulator developed within an object-oriented expert system shell

The efficient solving of process control problems often requires manipulating a wide spectrum of knowledge representations ranging from analytical knowledge to qualitative knowledge. These tendencies have been causing a growing interest for methods that are flexible enough to accommodate knowledge-based paradigms. In the paper, the simulator design of the amorphous SiO 2 precipitation process is described. From the control point of view, the process is a typical semibatch process containing discrete, as well as continuous dynamics. The simulator is developed in G2, which is an environment for the development of real-time expert systems and has been effectively used on a problem containing a great diversity of model descriptions.

Enhancement of an object-oriented expert system for contingency load transfer of distribution systems

This paper proposes a methodology to solve contingency load transfer of distribution systems by applying the object-oriented expert system. By this method, the faulted area is isolated and restored and the unfaulted, but out of service, area is restored effectively. Since the fault restoration has to be performed in a short time period and the affected area has to be constrained in a small area, it has become a critical issue to enhance the system reliability for the distribution system operation. The knowledge rule base with object-oriented programming can be designed to support distribution contingency management in an effective manner. The distribution facilities are designed as a class in the database and the distribution operation rules are created to form the knowledge base. To demonstrate the effectiveness of the proposed method, one of the Taipower distribution systems is selected for computer simulation. It is concluded that the contingency load transfer of distribution systems can be solved efficiently by identifying the proper switching operation to solve the distribution contingency problem.

Heuristic resolution for multiple inheritance in object-oriented expert system building tools

The inheritance dilemma (the problem of determining inheritance precedence) occurs when multiple superclasses have slots with identical names but different values. Multiple inheritance becomes a controversial feature in object-oriented paradigm because of inheritance dilemma. A consistent approach to this problem is necessary. Conventional approaches, such as static and dynamic approaches, were introduced. Static approaches cannot reflect the states of expert systems during inference, i.e., they lack adaptiveness. Dynamic approaches determine inheritance precedence according to inference results, but they rely heavily on functions in expert system building tools (ESBTs). Heuristic resolution is proposed as an alternative. Heuristic functions can simulate static and dynamic approaches, and can be implemented in object-oriented ESBTs. It is demonstrated that heuristic resolution is a dynamic, domain-independent, and general approach for the inheritance dilemma.

Object-Oriented Pumping-Test Expert System

An object-oriented Pumping-Test Expert System (PTES) is developed to assist hydrogeologists in the interpretation of pumping tests and the filing of technical reports. PTES features user-friendly, menu-driven, English/French dialogues and high-quality graphics. It contains over a dozen analytical interpretation methods and about 50 expert system rules for aquifers of confined, unconfined, and leaky types. It uses automatic curve fitting by nonlinear least squares but also allows the conventional visual matching of type curves. The system is implemented in a microcomputer using Borland C\u+\u+ in the Microsoft Windows environment. A few examples are provided to validate the code.

An object knowledge canonical form for knowledge reuse

The importance of knowledge reuse and sharing has been widely recognized. An Object Knowledge Canonical Form (OKCF) is created to translate object knowledge among commercial object-oriented expert system building tools (ESBTs): CLIPS 5.0, KAPPA, and KEE. The OKCF is represented in Backus-Naur Form (BNF), including identifiers, data types, data facts, simple facts, tuple facts, classes of facts, and structured facts. Following these BNF rules, translators have been implemented. These translators can be used to demonstrate the feasibility of OKCF. The use of OKCF in knowledge translation is effective. Besides, OKCF can serve as a reference for the development of new ESBTs. The OKCF can be integrated with knowledge acquisition tools for expert system prototyping. The OKCF is compared with Knowledge Interchange Format in various aspects: commitment to commercial ESBTs, support of important features, and applications.