Ayman Smadi

Advantages of Using Innovative Traffic Data Collection Technologies

Accurate traffic data are essential for supporting a multitude of transportation related decisions which affect transportation system operations, management, and planning. However, the lack of accurate and timely data is often cited as a common problem for both transportation practitioners and policy makers. This paper discusses the temporary use of advanced sensor technologies for collecting and presenting traffic data for supporting transportation system operations. It illustrates the use of video-based and radar-based traffic detection technologies. The range of applications included in this paper comprises specific traffic assessment, traffic signal operations, freeway performance evaluation, and highway work zones. In addition, the paper illustrates the significant value of video data in supporting transportation decisions among policy makers and the public. The paper covers two classes of advanced traffic detection sensors; the Autoscope Vide Vehicle Detection system and the Wavetronix SmartSensor Traffic Detector based on Digital Wave Radar. It discusses the potential applications, typical set up requirements, Types of data generated by these systems, and the performance of these technologies under different traffic condition environments. The information contained in this paper is based on various traffic operations projects conducted at the Advanced Traffic Analysis Center at North Dakota State University. These projects range from analysis of school traffic safety to evaluating traffic operations during a major multi-year construction project along Interstate Highway 29 in Fargo.

Use of Hardware-in-the-Loop Traffic Simulation in a Virtual Environment

A recent assessment by the National Transportation Operations Collation revealed unsatisfactory performance of a number of traffic signal operation areas and an overall score of D- for the nation’s traffic signals. This poor rating affects commuters nationwide and contributes to traffic congestion. Numerous traffic simulation models have been developed to analyze more complex transportation facilities. However, these models may have some shortcomings in accurately modeling complex traffic signal controller functions (which could have a drastic effect on operations). Hardware-in-the-loop simulation (HILS), which replaces a simulation’s signal control logic with actual controller hardware, allows advanced signal functionality to be tested and analyzed. Moreover, this simulation process opens new research areas in traffic controller functionality. This paper discusses the development of a controller interface device (CID) by the Advanced Traffic Analysis Center (ATAC) to support HILS. This CID improves upon existing devices in a number of ways, including: it works with the VISSIM traffic simulation model, uses current off-the-shelf technology, more cost effective, easy to setup and use, small in size, and its Ethernet connectivity allows it to communicate with CIDs/controllers virtually anywhere in the world.

North Dakota Gravel Road Management: Alternative Strategies

Gravel roads account for a large portion of the total 5.1 million km (3.2 million mi) of rural roads in the United States. These roads support the movement of farm families, rural residents, school buses, mail carriers, tourists, and agricultural commodities. In recent years, these roads have been affected by several trends. First, agricultural states are experiencing population shifts from farming areas to urbanized centers as farm sizes continue to grow, further reducing population densities and traffic levels. Second, some states such as North Dakota are experiencing a shortage in quality gravel supplies. Third, more rural road users perceive a lower level of service on gravel roads and demand better services, specifically more paved roads. Finally, the reduction in transportation budgets limits the number of gravel road kilometers that can be properly maintained. Several research efforts that examined alternative approaches to reduce gravel road maintenance costs are summarized here. These strategies may generally be classified into (a) modifying gravel road surface for high traffic roads (i.e., paving or using chemical additives), (b) reducing maintenance on gravel roads with lower traffic volumes, and (c) closing unneeded gravel roads. These options require careful economic and legal analysis before they would be implemented. The results of a case study that investigated the feasibility of paving gravel roads with various traffic levels and a brief overview of a survey of chemical soil additives in Colorado, Montana, North Dakota, South Dakota, Utah, and Wyoming are reported.

INNOVATIVE FINANCING METHODS FOR LOCAL ROADS IN MIDWEST AND MOUNTAIN-PLAINS STATES

Budget constraints for transportation projects is a growing problem at the federal, state, and local levels. At the same time, several changes have been affecting demands placed on the transportation systems, for example, population shifts, changes in travel patterns, and changes in economic activity. County and local governments are faced with increased demands on some portions of their road systems, and other portions have seen a drop in the level of use. As a result, these transportation agencies are facing tremendous challenges to maintain their extensive road networks and provide improvements when and where needed. Traditional funding sources are no longer adequate. There is a great need for counties to explore innovative methods to increase revenues or decrease costs or both. However, because of the nature of rural states (i.e., low population density and a limited tax base), methods used to supplement public funding of transportation projects in urban areas may not be applicable. Described are 4 innovative financing methods (e.g., rural improvement districts) and 14 cost reducing strategies (e.g., sharing equipment) used by local governments in eight rural states. County road officials identified these methods through a mail questionnaire and rated key criteria, such as ease of collection, to evaluate each method before implementing it. Rural improvement districts, special assessment districts, and the wheel tax were identified as innovative methods that are not widely used to raise revenues for a county road system. Advantages and disadvantages of each innovative financing method identified are discussed.