John W Shaw

Validation of Origin-Destination Data from Bluetooth Reidentification and Aerial Observation

Vehicle reidentification with Bluetooth signal data has emerged as an effective and economical means for collecting traffic data including origin–destination (O-D) information, which is crucial for transportation planning. Direct vehicle tracking based on time-lapse aerial photography (TLAP) is also increasingly used for O-D studies. Neither technique has previously been validated, so the objective of this study was to validate O-Ds generated by using both techniques against a ground-truth O-D. Traffic volume–, Bluetooth-, and TLAP-based O-D data collected at an interchange in Madison, Wisconsin, were used in this study. Significant variability (2.3% to 7.2%) in Bluetooth match rates was observed for the 12 O-D pairs of the interchange, which were calculated by using a heuristic measure of the difference between traffic volumes (the GEH formula). Uniproportional scaling of the sample Bluetooth O-D (using the average detection rate) resulted in poor fit to the true O-D, but biproportional factoring (Fratar or Furness procedure) resulted in about 85% of the movements’ having a GEH statistic less than 5. Combining Bluetooth data from multiple days resulted in a better fit than the use of a single days data. The analysis showed that Bluetooth technology could be used to obtain representative O-D information of an access-controlled network for planning applications. TLAP sample O-D data were scaled with an origin-specific factor and resulted in reasonable fit to the true O-D data. Biproportional factoring resulted in a better fit in which 100% of the movements had a GEH value less than 5. Therefore, biproportional factoring is also recommended for TLAP data.

A fuzzy AHP approach to compare transit system performance in us Urbanized areas

Public transit systems in the United States often face multiple policy objectives. Typically, stakeholders desire frequent service on an extensive network, but funding and other resources are constrained, creating complicated relationships between service effectiveness goals and business efficiency goals. Using data from the National Transit Map (NTM), this study evaluated the general performance of transit systems across 294 Urbanized Areas (UZAs) in the US, which were stratified into six peer groups based on population. Transit efficiency and effectiveness were compared by developing a composite business efficiency index score and a composite service effectiveness index score for each urbanized area. The scores were generated using a fuzzy logic extension of the Analytical Hierarchy Process (AHP), which allows automated weighting of the measures. The NTM currently includes a limited set of performance measures, and each transit agency’s data are associated with the largest urban area it serves; consequently, it is perhaps best-suited for identifying highperforming UZAs and less suitable for identifying the weakest performers. The analytical results suggest that a few UZAs (mainly densely-populated cities and university towns) are simultaneously able to achieve high scores on both business efficiency and service effectiveness. In most smalland medium-size conurbations, business efficiency appears to be a higher policy priority than service effectiveness.

Developing Australia’s Highway Safety Professionals: What Can the United States Learn?

Highway safety is a complex issue that requires the combined skills of many different types of professionals, including engineers, public administrators, first responders, and public health officials. Although the United States and Australia are culturally similar countries with high levels of motor vehicle use, for historical reasons Australia has typically reached road safety milestones earlier than the United States has. Although a few American universities offer classes on road safety, current U.S. offerings predominantly consist of professional development short courses (often with a programmatic focus). In addition to professional development courses, some undergraduate and postgraduate courses in Australian universities offer electives on the principles of road safety engineering and methods for influencing road user behavior. This coursework can be viewed as part of a wider effort to implement scientifically validated methods and the safe system approach recommended by the International Transport Forum of the Organisation for Economic Co-operation and Development. Deeper integration of highway safety principles into the undergraduate curriculum could assist both countries’ students in developing the leadership skills necessary to achieve higher levels of safety performance.

Special-Color Pavement Marking for Highway Work Zones: Literature Review of International Practices

Roadway lanes are often repositioned to accommodate highway work operations; as a result, pavement markings need to be altered. Although there are various methods for removing or obscuring existing pavement markings, “ghost” markings often remain at the locations of the old lane lines. These ghost markings can be quite conspicuous under certain lighting conditions, creating the potential for road user confusion. The Canadian province of Ontario and several European countries routinely use a special marking color (orange or yellow) to increase the salience of temporary lane lines. Special-color markings have also been used experimentally in Australia; New Zealand; Quebec City, Canada; and the United States. As a first step toward identifying the benefits and risks of special-color markings, existing practices from several countries are reviewed and summarized. The review identified a significant policy difference among jurisdictions: in some jurisdictions special-color markings override existing markings (so that the old markings are left in place), whereas other jurisdictions use special-color temporary marking but also attempt to remove old lane lines. The recent special-color marking demonstration projects in Australia, Canada, New Zealand, and the United States have been on major freeways, but European practice suggests that special-color marking could have significant benefit for urban arterial streets.