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Abstract: Urban and suburban freeways are designed to allow smooth traffic flow at high speed. However, when traffic demand is high or during irregular events, significant congestion may develop. Traffic [...]

Park-and-ride facilities are a valuable transportation systems management technique to combat congestion problems in and around city centers. It is therefore important for engineers and planners to determine their optimal location. Past research has identified many criteria that are relevant to optimal park-and-ride locations. But, although one criterion may carry more or less significance than another, they have always been considered on an equal scale. Furthermore, there is currently no system to use the existing knowledge and experience to aid planners in deciding the optimum location of a park-and-ride facility. In this project, a hybrid knowledge-based expert system/geographic information system tool was developed to help determine the optimal location for park-and-ride facilities. The tool was tested twice--on a set of hypothetical roadways and on another set of actual locations throughout the state of Delaware. In both cases, the program was successfully able to identify the same location that the selected expert engineers/planners chose as the optimal location for a park-and-ride facility given a set of potential sites. CE Database keywords: Geographic information systems; Parking facilities; Knowledge-based systems.

The Energy Policy Act of 1992 motivated transit agencies to utilize alternative-fuel transit buses in addition to their popular diesel buses. Transit agencies have planned to add a significant number of alternative-fuel buses to their current transit fleets. This study is to inform policy makers who may allocate public funds for alternative-fuel bus projects to make a smarter decision in this regard. For each of the eight alternative-fuel buses, technologies introduced by the ACT, fuel efficiency, life-cycle cost (LCC) and emission are estimated and compared with the available information for the ultralow-sulfur diesel (ULSD) fuel buses. A case study in the State of Delaware is presented to demonstrate how the proposed approaches can be employed to evaluate the relative importance of the most viable alternative-fuel transit buses according to the predefined set of criteria. The results show that buses propelled by hybrid-diesel engine have the least LCC and emissions and are the most suitable alternative for the ULSD buses in the short- and midterm. [ABSTRACT FROM AUTHOR]

Energy-efficient and environmentally sustainable public transportation systems are within the solution space provided by alternative fuel vehicles. Given the large revenue service potential of alternative fuel buses within the urban space, they are good candidates for emissions reductions when they are employed as part of a comprehensive urban transit planning process. The determination of the most appropriate alternative fuel bus asset for a given application is not necessarily that straightforward. The typical bus fleet is developed over a broad time horizon with each asset being acquired to meet a certain agency need or to close a perceived gap in the delivery of public transportation service. Therefore, as new assets are considered, it is critical for the fleet manager to consider as many factors of the fleet infrastructure to better ensure the positive impact that the newly acquired asset will have on fleet performance relative to the overall service goals and objectives of the fleet. This study investigates a broad range of alternative fuel bus technologies and the associated factors that will inform the decision-making process. Further, this work utilizes the inventory and understanding of the range of technology factors and leverages the perspective knowledge of industry experts on each of these factors to develop an expert systems decision-making philosophy to aid in the adoption of industry standards, best practices, consistency and sustainability in fleet asset management over time. [ABSTRACT FROM PUBLISHER]