OECD Workshop on knowledge-based expert systems in transportation. Vol. I

The objective of the workshop was to raise the awareness of the highway community (planners, decision makers, applications developers, etc.) regarding the potential for the application of knowl edge based expert systems in the highway transportation field.Additionally the workshop was to create a forum for the exchange of information among parties interested in expert systems development and to facilitate technology transfer.Working experience with knowledge based expert systems technology provided the context in which the workshop was held.The workshop consisted of five sessions, which were highly informative as the authors based their presentations on extensive working experience with knowledge based expert systems technology.This provided a mix of theoretical and practical and human considerations involved with the development, verification, validation, evaluation, implementation, and maintenance of knowledge-based expert systems.Session I, Developing Expert Systems, provided the background information necessary to understand the technology and its potential as a working tool in highway engineering and operations, and some of the prevalent issues and problems involved developing and using knowledge based expert systems.The topics covered ranged from technical issues such as definitions of the technology to practical issues such as validation and verification of expert systems to human considerations such as end user involvement in expert systems projects.Session II, Traffic Monitoring and Control, included discussions of systems developed or under develop ment to advise or assist with traffic monitoring and control operations such as managing non recurring freeway congestion, traffic signal control, and other applications.Practical issues such as field evaluation, user experience and acceptance, deep knowledge vs. surface knowledge, and others were addressed in the presentations.Session III, Traffic Impact Evaluation, focused on systems for reducing the impacts of roadside safety hazards.The integration of an existing algorithmic model into an expert system was addressed in this session.One other key issue that evolved during this session is that organizing and running knowledge based expert systems development projects is a complex and difficult task.Session IV on Highway Analysis and Planning covered systems designed to analyze roadway needs and problems such as bridge rail retrofit design and bridge foundation selection. Practical issues such as management and organizational needs and development tool selection were imbedded in the presenta tions.Session V on Highway Management highlighted systems designed to assist in maintenance and manage ment operations such as pavement management.Aspects of knowledge based expert systems develop ment and application that surfaced during this session included the technique of nesting systems within systems and the problems experienced in debugging and maintenance if the rule structure is too complex.