Abstract:
This annual meeting covered a wide variety of transportation issues. Bridge and Design issues were discussed, material and pavement specification, as well as strategic planning and traffic control.

Authors:
Anderson, K.W.

Keywords:
69th, Annual, bridge, control, design, Meeting, pavement, planning, specification, strategic planning, traffic, traffic control, transportation, TRB

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Abstract:
The purpose of this paper is to examine the distributional characteristics of daily travel distances and how these distances relate to day of week and trip purpose in the context of current electric vehicle range attributes. This evaluation indicated that there was at least a 25 percent probability that study participants would exceed 44 miles and a less than 6 percent probability that they would exceed 90 miles on any given weekday of travel. This suggests that at least 94 percent of the study participants daily travel needs, in terms of distances, may be met by electric vehicles with a range of at least 90 miles. In addition, cluster analysis suggest that upper limits may be closer to 138 miles for one cluster and between 150 and 220 miles for another, rather than 90 miles as defined by current EV range constraints. There are some individuals traveling in excess of this limit but who are still included in clusters driving fewer average daily miles. For these individuals, the data suggests that longer trips are infrequent and without recurring pattern and thus, in multi-car households, utilizing a conventional vehicle for these trips may be acceptable.

Authors:
Rutherford,G. S., Niemeier,D. A., Kooperberg,C.

Keywords:
TRB

Abstract:
The purpose of this paper is to present the results of a survival analysis for the duration of particular trip-making activities based on sex. Specifically, this study investigates the duration of those activities related to household and family support shopping, personal business, and free time and how these durations vary between men and women. It was found that there were no significant differences in the survival curves (i.e. durations) of free-time or personal business activities; this suggests that men and women spend approximately similar amounts of time on these activities; although it is not known if the activities themselves are similar (for example, banking versus getting gas). Alternatively, sex was found to be a very significant indicator of the duration of household and family support shopping activities. In the model specification, assuming all variables except sex are the same, it was found that women were 1.32 time more likely than men to spend a longer period of time in a household and family support shopping activity. Additionally, it was found that women are 1.33 times more likely than men to have a longer household and family support duration if the activity is nested in the journey to work trip.This report summarizes Phase I of the Prioritization Capacity Improvements (PCI) project. As part of this study, three tasks were completed. An evaluation of the existing prioritization method for capacity improvements was completed. A state-of-the-art assessment was conducted and included detailed review of three prioritization methods. Finally, a ranking methodology and evaluation criteria were proposed to address the state transportation policy goals associated with urban mobility. The framework and criteria are applicable for ranking general widening, SC & DI, HOV, bridge, interchange, and geometric capacity improvement projects. Phase II will add criteria addressing remaining state policy goals. Phase III will expand criteria to allow multimodal projects.

Authors:
Niemeier,D. A., Morita,J.

Keywords:
transportation planning, sex, work trip, shopping trip, TRB

Abstract:
To mitigate increasing traffic congestion and to improve highway safety, state departments of transportation have come up with some innovative strategies for optimizing the efficiency of congested freeway sections. Two such strategies are freeway-to-freeway ramp metering and mainline metering. Freeway-to-freeway ramp metering involves installing traffic signals (either on their side of the roadway or overhead) on the ramps found at freeway-to-freeway interchanges. Mainline metering involves installing traffic signals (usually overhead) on the mainline of a freeway. This paper examines some examples of freeway-to-freeway ramp metering in the United States, namely, in Minnesota and California. The advantages and disadvantages of freeway-to-freeway ramp metering are discussed. This paper then describes the only known operating example of mainline metering in the United States. Implementation and operational issues of mainline metering are discussed. The paper suggests that a complete and thorough analysis should take place prior to the installation of any freeway-to-freeway or mainline metering system. This analysis is needed to ensure that safety is maintained and that environmental concerns are addressed. The suggested policy on freeway-to-freeway ramp metering is as follows: 'Install meters on freeway-to-freeway ramps where system performance and efficiency will be improved.' The suggested policy on mainline metering is as follows: 'Install mainline meters on freeways approaching bottleneck locations where analysis indicates that improved traffic operations will result.' Guidelines for both metering types are listed in the paper.

Authors:
Klastorin,T., Pivo,G., Pilcher,M., Carlson,D., Hyman,C., Hansen,S., Hess,P., Thatte,A.

Keywords:
traffic surveillance and control, traffic congestion, ramp metering, TRB

Abstract:
Presented in this paper are findings from an empirical analysis to test the impacts of land-use mix, population density, and employment density on the use of the single occupant vehicle (SOV), transit, and walking for both work trips and shopping trips. The hypothetical relationships tested focused on whether there is a relationship between urban form and modal choice, whether this relationship exists when controlling for non-urban form factors, whether this relationship is linear or non-linear, and whether a stronger relationship exists between modal choice and urban form when they are measured at both trip ends as opposed to either the origin or destination. A review of literature and experiences suggested that a fair amount of information is known about the impacts of destiny on mode choice. However, considerable debate exists over whether density itself is actually the casual stimulus to a surrogate for other factors. To address this issue, a database was developed with a comprehensive set of variables for which density may be a proxy, e.g., demographics and level of service. This analysis employed a correlational research design in which modal choice was compared among census tracts with differing levels of density and mix. Findings from this research indicate that density and mix are both related to mode choice, even when controlling for non-urban form factors for both work trips and shopping trips. Furthermore, the relationship between population and employment density and mode choice for SOV, transit, and walking in non-linear for both work and shopping trips. Transit usage and walking increase as density and land-use mix increase, while SOV usage declines. Findings from this research suggests that measuring urban form at both trip ends provides a greater ability to predict travel choices than looking at trip ends separately. Findings also suggest that increasing the level of land-use mix at the trip origins and destinations is also related with a reduction in SOV travel and an increase in transit and walking.

Authors:
Frank,L. D.

Keywords:
land-use, mixed use, population density, SOV, transit, walking, TRB

Abstract:
This paper describes the use of an optimal recursive predictor (Kalman predictor) with inductance loop data to produce an anomaly detector. It details the construction of the system function or transition matrix, used in the optimal predictor, directly from the statistics of the problem. It demonstrates the use of a prediction algorithm with inductance loop data gathered on Interstate Five in Seattle, Washington. It discusses the scaling of thresholds necessary for anomaly detection but does not provide specific threshold values. This technique of dynamic prediction used with thresholds could have potential value to traffic management systems that rely heavily on inductance loop data.

Authors:
Dailey, D.J.

Keywords:
Traveler information, ITS backbone, distributed computing, client server model, ITS architecture, speed estimates, volume, occupancy, traffic surveillance and control, inductance loop data, traffic management systems, TRB

Abstract:
Transportation providers have employed several strategies to encourage ride sharing. This paper describes a new approach to promoting ride sharing among commuters. The approach involves convincing employer CEO\'s to provide employees ride share incentives. In Seattle, the Commuter Challenge program has challenged employers to \'Take the Challenge,\' become \'Pacesetters,\' and develop rideshare programs for their employees. In addition, this program has provided a forum in which transportation providers and employers have been able to discuss transportation issues. The program comprises representatives from transportation providers who work side by side with The Economic Development Council of King County (The EDC). The EDC represents over 800 businesses in King County. Since the beginning of the program in 1989, 98 major employers, representing over 270,000 employees in the Seattle area, have become Pacesetters. Four forums have been held to discuss transportation issues with employers.

Authors:
Legg,B.

Keywords:
Transportation planning, TRB, transportation management

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