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Portland State University

Civil and Environmental Engineering Faculty Publications and Presentations

Freight transportation -- Mathematical models

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Full-Text Articles in Engineering

Exploratory Methods For Truck Re-Identification In A Statewide Network Based On Axle Weight And Axle Spacing Data To Enhance Freight Metrics: Phase Ii, Mecit Cetin, Christopher M. Monsere May 2012

Exploratory Methods For Truck Re-Identification In A Statewide Network Based On Axle Weight And Axle Spacing Data To Enhance Freight Metrics: Phase Ii, Mecit Cetin, Christopher M. Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

Vehicle re-identification methods can be used to anonymously match vehicles crossing two different locations based on vehicle attribute data. This research builds upon a previous study and investigates different methods for solving the re-identification problem and explores some of the factors that impact the accuracy of the results. To support this work, archived data from weigh-in-motion (WIM) stations in Oregon are used for developing, calibrating, and testing vehicle re-identification algorithms. In addition to the Bayesian approach developed by the researchers in the previous study, a neural network model is developed for solving the re-identification problem. The results from the testing …


Freight Distribution Problems In Congested Urban Areas: Fast And Effective Solution Procedures To Time-Dependent Vehicle Routing Problems, Miguel A. Figliozzi Jan 2011

Freight Distribution Problems In Congested Urban Areas: Fast And Effective Solution Procedures To Time-Dependent Vehicle Routing Problems, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Congestion is a common phenomenon in all medium to large cities of the world. Reliability of freight movement in urban areas is an important issue to manufacturing or service companies whose operation is based in just-in-time approaches. These companies tend to provide high value or time sensitive products/services. As congestion increases, carriers face increasing challenges to satisfy their time sensitive customers in an economical way. Route designs or schedules which require long computation times or ignore travel time variations will result in inefficient and suboptimal solutions. Poorly designed routes that lead freight vehicles into congested arteries and streets not only …


Freight Performance Measures: Approach Analysis, B. Starr Mcmullen, Christopher M. Monsere May 2010

Freight Performance Measures: Approach Analysis, B. Starr Mcmullen, Christopher M. Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

This report reviews the existing state of the art and also the state of the practice of freight performance measurement. Most performance measures at the state level have aimed at evaluating highway or transit infrastructure performance with an emphasis on passenger transportation. Freight performance measurement ultimately requires evaluation of performance of the entire freight transportation system, which includes highways, waterways, rail, air, and modal connections. This requires considerable expansion of thinking beyond the traditional focus of state Departments of Transportation (DOTs) on highway performance.

This project builds upon past and current work in the area of freight performance measurement and …


The Impacts Of Congestion On Commercial Vehicle Tours Characteristics And Costs, Miguel A. Figliozzi Dec 2007

The Impacts Of Congestion On Commercial Vehicle Tours Characteristics And Costs, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Congestion is a common phenomenon in all major cities of the world. Increased travel time and uncertainty brought about by congestion impacts the efficiency of logistics operations. Recent studies indicate that a significant proportion of commercial vehicle kilometers traveled (VKT) and vehicle hours traveled (VHT) are generated by trip-chains or multi-stop tours. This paper presents research demonstrating the impact of congestion on multi-stop tours in urban areas. An analytical model, numerical experiments, and real-world tour data are used to understand the impact of congestion on tour characteristics, carriers? costs, VKT, and VHT. This research shows that travel time/distance between customer …