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96 Exhibit 101 illustrates how the recommended modeling system meets the research objectives. C H A P T E R 1 0 Accomplishment of Research Objectives
97 Research Objectiv e Degree Accomplished By Proposed Model Sy stem 1. Produce updated chapter on multimodal LOS analysis for urban streets for Highway Capacity Manual. Produce sample problems. Produce software engine. Draft chapter, sample problems, and software engine delivered to panel in June 2007 and to Highway Capacity Committee in July 2007. Final Report delivered February 2008. 2. Establish a scientific basis for evaluating level of service as a function of traveler satisfaction. The research has established a measurable definition of level of service and a reproducible method for measuring it. The model system is based on video labs and field surveys conducted in several cities in the United States. 3. Create a consistent set of modal LOS models allowing for comparison of degrees of modal traveler satisfaction across of modes. The uniform definition of LOS used in the models provides a consistent basis for comparing levels of service across modes. 4. Provide a multimodal LOS system that takes into account interactions among modes in the urban street environment. The multimodal LOS system takes into account the impacts of autos, buses, bicycles, and pedestrians on the perceived LOS for each mode. Many cross- modal factors are taken into account directly, others are incorporated indirectly. Explicit numerical methodologies do not yet exist for incorporating the indirect effects into the LOS models, but the âhooksâ are in place in the LOS models for future incorporation of new methods for estimating the indirect effects. 5. Create a multimodal LOS system that is applicable to arterials and major collectors The LOS system is applicable to arterials and major collectors. 6. Create a multimodal LOS system that addresses all vehicle and pedestrian movements. The multimodal LOS system concept allows the consideration of all movements by vehicles and pedestrians. The LOS models themselves have been implemented primarily for through travel along the arterial or collector. The pedestrian model, in addition, incorporates mid-block crossing. 7. Create a multimodal LOS system that can be used to evaluate micro-peaks (less than 15 minutes). The LOS system can be applied to peaks shorter than 15 minutes; however, the models that implement that system are designed for 15 minute peaks. 8. Incorporate safety and economic aspects only insofar as they influence perceptions of LOS. Safety and economic effects have not been explicitly included or excluded from the LOS models. Laboratory and field survey participants were allowed to consider any aspect of the service provided in determining their perceived levels of service. 9. Overcome the nine limitation of the HCM listed in Chapter 15 of the HCM. a. The presence or lack of parking is included in the bicycle and pedestrian LOS models. It indirectly affects the auto and transit LOS models. b. Driveway density and access control is included in the bicycle LOS model. c. Short lane additions and drops are not explicitly included in any of the LOS models. d. The impacts of road gradients are not included in the currently proposed LOS models, but could be added. e. Capacity constraints between intersections are taken into account to the extent they affect stops by autos or delay bus service. f. Two-way left turn lanes and medians are not explicitly included in the LOS models but can indirectly affect auto and bus LOS by reducing stops, or increasing bus speeds. g. High percentage turning movements explicitly affect pedestrian LOS. They indirectly affect auto and bus LOS. h. Multi-block queues will cause problems for the auto LOS model, which considers only stops . Under the recommended model, a single stop for a long queue gives better auto LOS than multiple stops for several short queues. i. Cross street congestion blocking through traffic will indirectly affect auto and bus LOS and will directly impact pedestrian LOS. Exhibit 101. Satisfaction of Research Objectives by the Recommended Modeling System.
