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Automated monitoring of traffic conditions in traffic management systems is of increasing importance as the sizes and complexities of these systems expand. Accurate monitoring of traffic conditions is dependent on accurate input data, yet techniques that can be used to screen data and remove erroneous records are not used in many traffic management systems. Procedures that can be used to perform quality checks on the data before their use in traffic management applications play a critical role in ensuring the proper functioning of condition-monitoring methods such as incident detection algorithms. Tests that screen traffic data can be divided into two categories: threshold value tests and tests that apply basic traffic flow theory principles. Tests that use traffic flow theory use the inherent relationships among speed, volume, and occupancy to assess data validity. In particular, a test that derives the average effective vehicle length from the observed traffic variables detects a wide range of erroneous data. A new data-screening procedure combines both threshold value tests and traffic flow theory–based tests and can serve as a valuable tool in traffic management applications.

The Specific Pavement Studies Experiment 5 (SPS-5) in the Long-Term Pavement Performance program was designed to study the effects of overlay rehabilitation type on typical distress measures. The rehabilitation treatments compared overlay thickness, overlay type, and surface preparation before rehabilitation. The thicknesses used were 50- and 125-mm overlays. The overlay types were virgin asphalt mix and recycled asphalt that contained approximately 30% reclaimed asphalt pavement (RAP). Surface preparation consisted of either milling or not milling the existing pavement before rehabilitation. Eighteen states and provinces in North America built SPS-5 projects between 1989 and 1998. Seven distress parameters from these test pavements were analyzed, including international roughness index (IRI), rutting, fatigue cracking, longitudinal cracking, transverse cracking, block cracking, and raveling. Analyses were conducted to determine which factors affected overlay performance as measured with the above parameters. Further statistical testing compared the performance of the virgin mix sections directly with equivalent sections that contained 30% RAP. Overlays with mixes that contained 30% RAP were found to perform as well as overlays with virgin mixes in terms of IRI, rutting, block cracking, and raveling. Thicker overlays improved pavement performance, except for rutting. Milling before rehabilitation decreased IRI, fatigue cracking, and transverse cracking but increased rutting.

Instructional practices in transportation engineering education are evolving, and only some of these changes have been documented in the literature. This paper provides a systematic review of journal articles and refereed conference papers that address innovations in transportation engineering education; the focus is on novel instructional practices and their influence on student learning. The literature review finds 46 articles for analysis, with an increasing frequency of those publications over time. Instructional practices described in these papers include simulation, visualization, problem-based learning, and other active-learning techniques. Most of these articles were written by individual researchers or a team of researchers at a single institution, and few of the articles cite one another; this finding suggests a need for more effective dissemination. Techniques for measuring student learning include in-person interviews, a variety of survey types (typically multiple choice or open-ended), concept maps, and direct assessment of student work. These techniques are implemented mostly as postassessments, but in some work, a pre- and postcourse experimental design is employed. It is clear that more rigorous evaluation of student learning, resulting from changes in teaching practices, should be considered. This analytical review of the literature provides a resource for transportation engineering educators to identify pedagogical practices that are relevant to their courses and suggestions for how to measure the effect of these techniques on student learning.