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Tracking vehicles through roundabouts is laborious. Because of this, turning movement volumes are usually estimated using a variety of methods. This paper identifies and evaluates practical methods of estimating turning movement volumes at roundabouts. Thirty four experiments were used to test the effects of different estimation treatments: estimation procedure, time interval size, count location configuration, and turning movement sample procedure. A new economical sampling procedure was introduced and included in the experiment design. The experiments were evaluated using volume estimation and capacity estimation errors. Findings showed that the new sample procedure works well relative to a random sampling procedure. Other insights were gained regarding the four treatments included in the experiment design. DOI: 10.1061/(ASCE)0733-947X(2007)133:2(138) CE Database subject headings: Volume measurement; Intersections; Estimation; Traffic volume; Evaluation.

Parallax error is a distance-related measurement error when the measurement has to rely on field of view, such as video-image systems. This paper provides a detailed investigation of the geometric elements associated with parallax error in video-image systems. A field-of-view calibration model is presented based on a study of various geometric elements, including camera height, camera location, view of image, and vehicle dimension. The study found that parallax error ranges between 10 and 50% based on normal camera setup. The model presented provides a better understanding of the parallax error; thus the accuracy of distance-related measurements could be improved when video-image systems are deployed. The proposed model has special application values at signalized intersections where video-image systems are deployed. One of the applications is to identify the range of possible blockage by a leading vehicle, which is one of the major causes of missed detections. Another application is to identify the conditions that result in vehicle occlusion, which is a source of false detections. CE Database keywords: Errors; Measurement; Imaging techniques; Transportation engineering.

The article discusses the efforts of the curriculum subcommittee to the Institute of Transportation Engineers (ITE) Education Council to map the learning domain of transport engineers. It describes their development of learning outcomes and knowledge tables which are grouped into traffic operations and highway capacity, geometric design and traffic safety, to name some. All of these efforts are for the purpose of developing the Introductory Course in Transportation Engineering.

The article discusses the results of the survey on the practice in transportation engineering education in the U.S. It was found that 80 percent of the 224 civil engineering programs require one or two undergraduate transportation engineering courses. Instructors were found to push students in higher cognitive skills like applying technical knowledge, solving problems, and analyzing data. At least 75% of the instructors have identified resources that help improve learning outcomes of students.

Most commercially available video detection systems are unable to differentiate turning movements at intersections. Therefore, special applications need to be developed. Using the basic time events recorded by a video detection system, a vehicle-tracking algorithm was developed to track vehicles and measure speeds at two-way, stop-controlled intersections. [ABSTRACT FROM AUTHOR]

Deals with the use of peak hour warrant graphs for intersection traffic control selection in the United States. Overview of the 1994 Highway Capacity Manual; Intersection characteristics; Calculation of intersection level-of-service and delay; Suggestions for improved study.