A. Essam Radwan

A VERIFICATION APPROACH FOR KNOWLEDGE-BASED SYSTEMS

Abstract Knowledge-based systems (KBS) represent a novel computer-based approach for dealing with practical traffic engineering problems. As traffic engineers adapt and apply KBS technological tenets, there is a need to reflect on exactly how development efforts should proceed and, particularly, on how a KBS should be verified as “correct.” Such experience is likely to accrue from hindsight; what went right—or wrong—during an actual KBS project. Unfortunately, hindsight does not provide direct experience with the application of a specific development paradigm. In this paper, we detail our experiences in applying a specific verification framework (based on traditional software engineering tenets) during a traffic engineering KBS development effort. Our experiences with this paradigm provide useful insights to other researchers involved in traffic engineering KBS development projects.

TOLL NETWORK CAPACITY CALCULATOR: OPERATIONS MANAGEMENT AND ASSESSMENT TOOL FOR TOLL NETWORK OPERATORS

A performance assessment tool was developed to assist managers and operators of highway networks containing toll collection facilities. The toll network capacity calculator (TNCC) quantifies a toll facility’s ability to process traffic. The calculator can also help engineers who are designing toll facilities to serve highway systems adequately. TNCC determines the maximum amount of traffic that a collection facility can handle. In addition, TNCC may be used for disruption management during lane closings, incidents, or maintenance checks. Furthermore, TNCC may be employed as a planning tool and a performance assessment tool by predicting the impact of surging traffic volumes during special events. The performance of a toll facility was determined from plaza characteristics such as lane number, lane type, and processing rates. The results of the calculations met constraints set by the characteristics of the arriving traffic. For example, variables such as the percentage of arrivals that were electronic toll collection (ETC) patrons and the percentage of arrivals that were semitrailer trucks requiring non-ETC services influenced the plazas’ performance outcome. Overflow of ETC users from the dedicated ETC lanes into the mixed lanes was also a factor. Performance was independent of hourly arrival volumes. Videotapes and transaction data at plazas provided necessary input to TNCC in the evaluation of 32 plazas on the toll network of highways in Orange County, Florida.

Management of Accidents Working Group

This chapter contains some of the results of Pilot Study “Dioxin Problems, a project concerning the international exchange of information on polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and related chemicals. The project was undertaken by the Committee on the Challenges of Modern Society (CCMS) of the North Atlantic Treaty Organization (NATO). In addition to the major objective, secondary goals included assistance in identification of knowledge voids and reduction of research program duplication. Several NATO-member nations participated in the project. They were: Canada, Denmark, the Federal Republic of Germany, Italy, the Netherlands, Norway, the United Kingdom, and the United States. Other participants were international organizations as well as representatives of industrial trade associations and nongovernmental environmental groups.

TRANSPORTATION OF HAZARDOUS MATERIALS ON ARIZONA'S LOW VOLUME ROADS

This paper attempts to address the issue of transporting hazardous materials and the question whether this activity constitutes a significant problem on Arizonas low volume roads. Problems related to lack of data required for most of existing risk assessment models are discussed. A preliminary risk assessment, conducted by the use of a screening model, attested that of the total state low volume road mileage, only 30% may need further, and more detailed, hazardous materials transportation risk analysis. The remaining 70% is currently free of any significant risk.