The growing number of trucks traveling on freeways has caused more traffic congestion and increased the likelihood of truck-related crashes. Many transportation agencies are considering a new concept of truck-only toll (TOT) lanes to provide a more efficient and safer freight transportation system. This research develops a methodology for identifying candidate TOT lanes in the freeway system. The modeling of TOT lanes in different geographic applications includes individual TOT corridors, a regional TOT network, and a statewide TOT network. The criteria employed in a geographic information system (GIS)-based screening process to determine feasible TOT corridors and their boundaries/extents include: freeway level of service, truck volumes, truck percentage of total freeway flow, truck-related crashes, and truckers willingness to pay. The research also presents the process for determining optimum toll rates for TOT lanes. Furthermore, this research addresses issues of assessing the engineering design of TOT lane placement and the performance measures of using either mandatory or voluntary TOT lanes. This research also examines freeway performance under two scenarios -- adding general purpose lanes or building TOT lanes with both mandatory and voluntary use. Finally, this research addresses the strategies for critical issues associated with the planning, design, and operation of TOT lanes and presents TOT planning guidance.

MPLS, the next-generation backbone architecture, can speed up packet forwarding via label switching. However, if the traversed LSPs (Label Switching Paths) are in congestion, traffic may encounter serious throughput degradation due to packet loss. This performance degradation may become worse and worse unless another forwarding LSP for these traffic flows are allocated. Moreover, in this Thesis, we propose a preemption mechanism for higher-priority flows to obtain necessary resources (the bandwidth of a LSP) by preempting low-priority traffic flows. In the multiple-flow preemption mechanism, several LSPs between Ingress router and Egress router are established to forward traffic flows. Some of these traffic flows are higher priority with stringent QoS requirements. If no satisfactory throughput can be met, Egress router would have to feedback average throughput values to Ingress router, which in turn decides how many lower-priority traffic flows should be preempted and moved to another LSP. Consequently, Ingress router has to send bandwidth reservation messages to reserve bandwidth just released by those lower-priority flows. After that, every core router can process these MPLS packets with specified traffic class to meet their QoS requirements. Finally, for the purpose of demonstration, we embed multiple flow preemption modules into MNS simulator and use it to run some experiments. Since in our scheme, it is not necessary to reserve bandwidth for higher-priority traffic flows in advance, the overall bandwidth utilization can be increased. Furthermore, the higher-priority flows can meet their QoS requirements by preempting the lower-priority flows whenever it is needed.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 128-130).

Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 224-240). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 377-389). Available also in a digital version from Dissertation Abstracts.

Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2003. / Includes bibliographical references (p. 93-94).

Thesis (M. Phil.)--University of Hong Kong, 1974. / Mimeographed.

Thesis (Ph. D. in Civil and Environmental Engineering)--University of California, Berkeley, 2003. / "Fall 2003." Includes bibliographical references (p. 131-136). Also available online at the ITS Berkeley web site (www.its.berkeley.edu/publications).

Thesis (Ph. D. in City and Regional Planning)--University of California, Berkeley, 2003. / "Fall 2003." Includes bibliographical references (p. 173-183). Also available online via the ITS Berkeley web site (www.its.berkeley.edu).

Urban freeway demand that frequently exceeds capacity has caused many agencies to consider many options to reduce congestion. A series of solutions that falls under the Active Traffic Management (ATM) banner have shown promising potential. Perhaps the most popular ATM strategy is ramp metering. Ramp metering involves limiting the access of vehicles to freeways at an entrance ramp. By doing this, freeway throughput, speeds, and travel time reliability can be increased, while the number of traffic incidents can be decreased. This study examines the application of an innovative ramp metering strategy, Intersection Ramp Metering (IRM), at a section of Loop 1 in Austin, TX. IRM implements the ramp metering function at the intersection immediately upstream of the entrance ramp, rather than on the ramp itself. A microsimulation analysis of this application is performed in VISSIM, and the results confirm that freeway throughput (+10%), and system average travel time (-14%), can be improved, as well as several other performance measures. / text