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This paper investigates the platoon dispersion model that is part of the Highway Capacity Manual 2010 (HCM 2010) and is used to forecast downstream traffic flows for analyzing both signalized and two-way stop-controlled (TWSC) intersections. The paper focuses on the effect of platoon dispersion on proportion of time blocked, conflicting flow rate, and capacity flow rate for the major street left-turn movement at a TWSC intersection. Existing HCM 2010 methodology shows little effect on conflicting flow or capacity for various distances downstream from the signalized intersection. Two methods are suggested for computing the conflicting flow and capacity of minor stream movements at a TWSC intersection that have more desirable properties than the existing HCM method. Further, if the existing HCM 2010 method is retained, results suggest that the upstream signals model be dropped from the HCM method for TWSC intersections.

This paper investigates the platoon dispersion model that is part of the 2010 Highway Capacity Manual that is used for forecasting downstream traffic flows for analyzing both signalized and TWSC intersections. The paper focuses on the effect of platoon dispersion on the proportion of time blocked, the conflicting flow rate, and the capacity flow rate for the major street left turn movement at a TWSC intersection. The existing HCM 2010 methodology shows little effect on conflicting flow or capacity for various distances downstream from the signalized intersection. Two methods are suggested for computing the conflicting flow and capacity of minor stream movements at the TWSC intersection that have more desirable properties than the existing HCM method. Further, if the existing HCM method is retained, the results suggest that the upstream signals model be dropped from the HCM method for TWSC intersections.

The Storm Warning Project was initiated in 1993 as a result of a large number of serious traffic crashes that occurred during periods of low visibility on I-84 in southeastern Idaho between 1988 and 1993. The purpose of the project was to determine if visibility sensors and the resultant information supplied to drivers on roadway message signs would reduce vehicle speeds to safe levels as warranted by weather conditions. The report is organized to provide information in a sequence that corresponds to the chronology of the project. Section 1 introduces the project, and provides an overview of its history, a description of the systems tested, test objectives, and evaluation approach. Section 2 reports on the performance and reliability of the sensors. It documents Phase I of the project, which involved evaluating the sensors' ability to determine low visibility conditions. Section 3 discusses the response of drivers to the driving conditions and to the information provided by variable message signs. It documents Phase II of the project, which studied the degree to which driver behavior could be modified through presentation of roadway condition information via variable message signs. Section 4 presents the results and conclusions of this operational test.

The Department of Transportation's new Intelligent Transportation System (ITS) program mandates that computing, communications, electronics, and other advanced technologies be applied to improving the capacity and safety of the nation's transportation system. In order to put these technologies into practice, a new generation of transportation engineers need a set of multidisciplinary engineering skills that are not typically included in a civil engineering-based education program. In response to this need, NIATT developed Traffic Signal Summer Camp (TSSC), an intensive five-day experience in which twelve top transportation engineering students from the U.S. and abroad have the opportunity to work hands-on with the latest traffic signal control hardware and software. Each of the camp's five days focus on a specific aspect of advanced traffic signal systems, and includes a blend of lecture, lab, and hands-on exercises. NIATT conducted two TSSC camps, both held on the University of Idaho campus in Moscow, ID. The first was held in August of 2000 and the second in August of 2001. (93 p.)

DTRT07-G-0056, The goal of this work was to develop activity-based learning materials for the introductory transportation engineering course, with the purpose of increasing student understanding and concept retention. These materials were to cover intersection, operations from a multimodal transportation approach. The initial framework was to create a set of 4 activities, the first, activity focused solely on automobile transportation, and the subsequent activities adding one additional transportation, mode each. For the final work, the existing sequence of material in the textbook was used for activity development. The, final work included the development of a handout for Dr. Kyte’s critical movement analysis method, a queuing systems, field lab, a pedestrian and bicycle level of service lab, and a transit level of service lab. The lab activities provided an active, learning experience, two focusing on non-auto modes. These activities facilitated a fundamental and broad understanding of, core concepts in transportation engineering. This work has provided me with a better perspective on instruction of this topic, and with specific future goals, including better integration of multimodal transportation into the existing curriculum, addressing issues in the textbook, and fine-tuning the work that was previously completed.

The Out-of-Service Verification Field Operational Test Project was initiated in 1994. The purpose of the project was to test the feasibility of using sensors and a computerized tracking system to augment the ability of inspectors to monitor and control the status of vehicles that had been placed out of service until the violations were cleared. As such, the system not only required development of new technology for vehicle sensing, but it also required interfacing into an existing inspection computer record system (ASPEN) and a well- developed methodology of inspection that was comfortable for both drivers and inspectors. The project was conducted in Boise, Idaho by a partnership that included the Idaho State Police (ISP), the Idaho National Engineering and Environmental Laboratory (INEEL), the Idaho Transportation Department (ITD), and the U.S. Department of Transportation (U.S. DOT). The University of Idahos National Institute for Advanced Transportation Technology (NIATT) is the independent evaluator for the project.

University Transportation Centers Program, 2008, PDF, Research Paper, Thom, Ronald, Gaeckle, Jeff, Borde, Amy, Anderson, Michael, Durrance, Cynthia, Kyte, Michael, Schlenger, Paul, Stutes, Jason, Weitkamp, Don, Wyllie-Echeverria, Sandy, Rumrill, Steve, Boyle, Matthew, Pacific Northwest National Laboratory, Washington (State). Department of Natural Resources, Grette and Associates, Precision Identification Biological Consultants, ENSR, Anchor Environmental, L.L.C., Parametrix, University of Washington. School of Marine Affairs, South Slough National Estuarine Research Reserve, PENTEC Environmental/Hart Crowser, Inc., United States. Department of Energy, United States. Department of Transportation. Federal Highway Administration, Washington State Transportation Center, Pacific Northwest National Laboratory, British Columbia, Washington, Oregon, Pacific States, Grasses, Restoration ecology, Environmental protection, Stream restoration, Ecosystems, Endangered species, Habitat (Ecology), Marine soils, Aquatic life, Transplanting, Planting, Landscaping, Eelgrass, PNWD-3970, WA-RD 706.1, We summarize eelgrass (Zostera marina L.) restoration and mitigation project results and recommendations of transplant practitioners in the Pacific Northwest since 1990. Our purpose is to provide current information for programs considering eelgrass restoration by providing a synthesis of what practitioners and researchers have learned through experimentation and monitoring of discrete projects throughout western Washington and British Columbia. Reports, papers, personal communications, and a workshop were used to gather data on these projects. Our general null hypothesis is that eelgrass can be restored to match natural eelgrass meadows in terms of structure and function. We conclude that, under favorable site conditions, and if the reason for the initial loss of eelgrass is understood and corrected, that eelgrass can be restored. However, eelgrass restoration science is hampered by knowledge gaps, reducing restoration success. For example, mechanisms for recent eelgrass loss in the region are not obvious, which suggests that the scientific understanding of eelgrass biology and ecosystem conditions is inadequate to support environmental management actions in our region. To improve restoration project success in the Pacific Northwest requires further research knowledge gaps, closely evaluating the performance of restoration projects, and disseminating information for use by future generations. Workshop participants identified an immediate need to construct a clearinghouse of eelgrass restoration and monitoring results that provides summaries and data from eelgrass enhancement efforts. Furthermore, we found that it was difficult to summarize the relative performance of the more than 30 projects reviewed because of variations in goals, project size, planting methods employed, performance criteria, duration of monitoring, intensity of monitoring, and data interpretation. Hence, we recommend that standard monitoring protocols be developed and results from these methods, 1333