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Horizontal curves present drivers with numerous tasks that, if not performed while approaching and negotiating the curve, may result in a roadway departure crash. A vehicle's lateral position within the lane and its speed are two indicators of interest from safety and operational perspectives. These can and have been measured simultaneously at multiple locations along the curve. However, researchers face the challenge of collecting operational data while minimizing impacts on driver behavior, and developing robust, efficient, and accurate means to obtain the data. This paper presents the findings of a series of pilot studies on closed and open courses that investigated the effectiveness and accuracy of pneumatic road tubes and digital video cameras for collecting such data. Closed-course studies investigated a single data collection station setup, whereas an open-course study investigated multiple data collection stations on a horizontal curve. The data were reduced manually and automatically, and tests were performed to evaluate the statistical significance of the results. In general, the pilot studies show that pneumatic road tubes provide a higher level of accuracy than video data. Other findings include that drivers moved towards the centerline of the roadway overall and even more so when the presence of video equipment. It was also found that vehicle mean speeds at the center of the curve were lower with an increase amount of data site-based vehicle data collection equipment present. [ABSTRACT FROM AUTHOR]

Red light running causes more than 100,000 crashes and 1,000 fatalities annually and results in an estimated economic loss of over $14 billion per year in the United States. Red light running is a significant safety issue facing communities which rarely have the resources to place additional law enforcement in the field. As a result, communities are increasingly turning to automated red light running camera-enforcement systems to address the problem. The effectiveness of red light running cameras in reducing the number of drivers who run the red light (violations) in an Iowa community was evaluated. The number of red light running violations at camera-enforced intersection approaches were compared to violations at approaches at intersections where cameras were not used within the same metropolitan area using a cross-sectional analysis. A Poisson lognormal regression was used to evaluate the effectiveness of the cameras in reducing violations. Results indicated that red light running cameras substantially reduced the number of violations at camera-enforced approaches as compared to control approaches. [ABSTRACT FROM AUTHOR]