The Type-II dilemma zone refers to the segment of roadway approaching an
intersection where drivers have difficulty deciding to stop or proceed through at
the onset of the circular yellow (CY) indication. Signalized intersection safety can
be improved when the dilemma zone is correctly identified and steps are taken to...
At signalized intersections, pedestrians are considered to be amongst the most vulnerable. When in the crosswalk at intersections without protected left-turn phasing, pedestrians are particularly at risk from left-turning vehicles. Until recently, a wide variety of indications were in use across the US to indicate a permissive left-turn condition to...
This thesis develops a framework for analyzing the application of commuter rail and
bus services between several small urban centers to enhance overall connectivity. The
study includes analyzing specific performance criteria for commuter rail service and
express bus service based on data from existing systems around the U.S. The study...
Driver distraction is a commonly observable phenomenon with a significant effect on the transportation network. Although the negative effects of driver distraction on safety are commonly studied, there has been little effort made to investigate the impacts of distraction on efficiency.
This study will examine driver behavior in standing queues...
Highway construction projects require temporary changes in roadway characteristics, such as the number of operational lanes, lane path, lane width, shoulder width, and posted speed limit. These modifications which are often temporary in nature have the potential to impact driving performance. Many research efforts have focused on developing standards to...
Traffic signal countdown timers (TSCT) are innovative, practical and cost effective technologies with the potential to improve efficiency and safety at signalized intersections. The purpose of these devices is to assist motorists in decision making at signalized intersections with real time signal change information. While successful implementation of these devices...
A Right-hook (RH) crash is a common type of bicycle-motor vehicle crash that occurs between a right-turning vehicle and through-moving bicycle at an intersection. At signalized intersections, RH crashes can occur at the onset of the green or during the latter portion of the green phase. In spite of the...
Pedestrian distraction at roadway crossings has been correlated with a higher risk of pedestrian-vehicle collisions due to the pedestrian's cognitive, visual, and motor attention being drawn to a wide variety of secondary tasks.
This study is different from previous field studies of pedestrian midblock crossings in that the geometric layout...
Large truck-involved crashes have a significant impact on both the economy and society. They are associated with high injury severities, high crash costs and contribute to congestion in urban areas. Past studies have investigated the contributing factors of large truck-involved crashes, however a study isolating the spatial and temporal effects...
A right-hook crash is a bicycle-motor vehicle crash between a right-turning motor vehicle and an adjacent through-moving bicycle. This study focuses on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections with shared right-turn and through lanes. The overall objective was to evaluate...