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Full-Text Articles in Transportation

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 …


Highway Safety Investigation Manual For The Oregon Department Of Transportation, Karen Dixon, Christopher Monsere Jan 2011

Highway Safety Investigation Manual For The Oregon Department Of Transportation, Karen Dixon, Christopher Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

Across the state, region, and nation highway safety investigators have developed a wide variety of tools and techniques for highway safety investigation procedures. Analysis techniques can range from systematic evaluation approaches such as the Oregon Department of Transportation’s (ODOT’s) Safety Priority Index System (SPIS) down to specific localized safety assessment strategies. It is important to develop consistent methods for safety evaluations across Oregon to ensure that safety investigations are conducted in a similar manner. It is also important to develop a screening process for proper highway safety investigations and document the procedures used for this assessment.

The objective of this …


Evaluation Of The Iqa Delay Estimation Method, Yaye Keita, Mitsuru Saito Jan 2011

Evaluation Of The Iqa Delay Estimation Method, Yaye Keita, Mitsuru Saito

CUTR Faculty Journal Publications

The Incremental Queue Accumulation (IQA) method is the new delay estimation method for signalized intersections adopted for the Highway Capacity Manual 2010. Using a signalized intersection and a remote data collection facility, the IQA method was evaluated for its accuracy and for potential challenges that practitioners may encounter as they use the new method. The results were compared with delays obtained by the delay estimation models included in the Highway Capacity Manual 2000. It was found that the IQA method was promising and theoretically more robust than the current delay estimation model, but field data collection could be challenging. © …


Evaluation Of Video Based Pedestrian And Vehicle Detection Algorithms, Varun Bandarupalli Dec 2010

Evaluation Of Video Based Pedestrian And Vehicle Detection Algorithms, Varun Bandarupalli

UNLV Theses, Dissertations, Professional Papers, and Capstones

Video based detection systems rely on the ability to detect moving objects in video streams. Video based detection systems have applications in many fields like, intelligent transportation, automated surveillance etc. There are many approaches adopted for video based detection. Evaluation and selecting a suitable approach for pedestrian and vehicle detection is a challenging task. While evaluating the object detection algorithms, many factors should be considered in order to cope with unconstrained environments, non stationary background, different object motion patterns and the variation in types of object being detected.

In this thesis, we implement and evaluate different video based detection algorithms …


Analysis And Evaluation Of Safety Impacts Of Median Types And Midblock Left Turn Treatments For Urban Arterials, Timur Mauga Dec 2010

Analysis And Evaluation Of Safety Impacts Of Median Types And Midblock Left Turn Treatments For Urban Arterials, Timur Mauga

UNLV Theses, Dissertations, Professional Papers, and Capstones

Urban growth leads to new land-uses abutting arterials requiring driveways for their accessibility. Uncontrolled number and locations of such access points causes safety, mobility and accessibility problems. The solution to these problems is access management (AM) which controls the number and location of the access points. AM techniques are normally documented in the form of guidelines for engineers and planners to follow when implementing the techniques. However, AM guidelines may not cover every technique due to the fact that AM is still growing. For example, the current AM guideline prepared by The Nevada Department of Transportation addresses many AM techniques. …


Model-Based Analysis Of Electric Drive Options For Medium-Duty Parcel Delivery Vehicles, Robb A. Barnitt, Aaron D. Brooker, Laurie Ramroth Dec 2010

Model-Based Analysis Of Electric Drive Options For Medium-Duty Parcel Delivery Vehicles, Robb A. Barnitt, Aaron D. Brooker, Laurie Ramroth

Publications (T)

Medium-duty vehicles are used in a broad array of fleet applications, including parcel delivery. These vehicles are excellent candidates for electric drive applications due to their transient-intensive duty cycles, operation in densely populated areas, and relatively high fuel consumption and emissions. The National Renewable Energy Laboratory (NREL) conducted a robust assessment of parcel delivery routes and completed a model-based techno-economic analysis of hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle (PHEV) configurations. First, NREL characterized parcel delivery vehicle usage patterns, most notably daily distance driven and drive-cycle intensity. Second, drive-cycle analysis results framed the selection of drive cycles used …


Automobile Exhaust Gas Detection Based On Fuzzy Temperature Compensation System, Zhiyong Wang, Hao Ding, Fufei Hao, Zhaoxia Wang, Zhen Sun, Shujin Li Dec 2010

Automobile Exhaust Gas Detection Based On Fuzzy Temperature Compensation System, Zhiyong Wang, Hao Ding, Fufei Hao, Zhaoxia Wang, Zhen Sun, Shujin Li

Research Collection School Of Computing and Information Systems

A temperature compensation scheme of detecting automobile exhaust gas based on fuzzy logic inference is presented in this paper. The principles of the infrared automobile exhaust gas analyzer and the influence of the environmental temperature on analyzer are discussed. A fuzzy inference system is designed to improve the measurement accuracy of the measurement equipment by reducing the measurement errors caused by environmental temperature. The case studies demonstrate the effectiveness of the proposed method. The fuzzy compensation scheme is promising as demonstrated by the simulation results in this paper.


Tracking Missing Drivers, James G. Strathman Sep 2010

Tracking Missing Drivers, James G. Strathman

TREC Project Briefs

By understanding driver absenteeism, transit providers can learn to manage it, Portland State University research suggests.


Characteristics Of Transitions In Freeway Traffic, Robert L. Bertini, Soyoung Ahn Sep 2010

Characteristics Of Transitions In Freeway Traffic, Robert L. Bertini, Soyoung Ahn

Civil and Environmental Engineering Faculty Publications and Presentations

This research seeks to understand the characteristics of transitions as freeway traffic changes from one state to another. This study addresses the features of two types of transitions; transitions near a merge and transitions along shock waves during the onsets and dissipations of queues at several freeway sites.

Individual vehicle trajectory data were analyzed for studying the transitions near a merge. The length of a transition zone was measured by analyzing the spatial changes in flow, density and speed along kinematic waves near a merge. It was found that the length of transition in terms of flow, density and speed …


Research On Distribution Program Of Food Cold-Chain Logistics In Bright Speed Fresh Logistics Company, Zexin Xu Jul 2010

Research On Distribution Program Of Food Cold-Chain Logistics In Bright Speed Fresh Logistics Company, Zexin Xu

World Maritime University Dissertations

No abstract provided.


Case Study Of Cold Chain Logistics Business Of Third Party Logistics Company, Han Bao Jul 2010

Case Study Of Cold Chain Logistics Business Of Third Party Logistics Company, Han Bao

World Maritime University Dissertations

No abstract provided.


Reasonable Number Of Issuing Original Bill Of Lading, Zhongming Ren Jul 2010

Reasonable Number Of Issuing Original Bill Of Lading, Zhongming Ren

World Maritime University Dissertations

No abstract provided.


Evaluation Of Safety Impact Of Access Management In Urban Areas, Xuecai Xu May 2010

Evaluation Of Safety Impact Of Access Management In Urban Areas, Xuecai Xu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The access provided by streets and highways to adjacent lands are managed by controlling the spacings between the access points including signals, driveways, and media openings on mid-block segments, and setting the limit on the corner clearances around intersections. There have been studies on evaluating the impact of access management techniques on safety and mobility in urban areas. Samples of mid-block segments and intersections can be collected from selected arterials. Because the mid-block segments or intersections in the same arterials share the same missing information, safety and mobility on them show unique features that should be taken into account when …


Statistical Modeling And Analysis Of Injury Severity Sustained By Occupants Of Passenger Vehicles Involved In Crashes With Large Trucks, Ahmad Koupaenejad May 2010

Statistical Modeling And Analysis Of Injury Severity Sustained By Occupants Of Passenger Vehicles Involved In Crashes With Large Trucks, Ahmad Koupaenejad

UNLV Theses, Dissertations, Professional Papers, and Capstones

Crashes are the result of complex interactions between several factors representing driver, roadway, vehicle, and environmental characteristics. Understanding to what degree each factor contributes to the severity of a crash is not a simple task. The outcomes of crashes in the US have been an average of 42,000 deaths and 3 million injuries per year. To better understand the role of significant contributors to crashes, three sets of models using multinomial logit and one using ordered probit were calibrated. To calibrate these models, forty two independent predictor variables including driver/occupants characteristics, crash environment at the crash location, crash characteristics, and …


Integrated Vehicle Thermal Management For Advanced Vehicle Propulsion Technologies: Preprint., K. Bennion, M. Thornton Feb 2010

Integrated Vehicle Thermal Management For Advanced Vehicle Propulsion Technologies: Preprint., K. Bennion, M. Thornton

Publications (T)

A critical element to the success of new propulsion technologies that enable reductions in fuel use is the integration of component thermal management technologies within a viable vehicle package. Vehicle operation requires vehicle thermal management systems capable of balancing the needs of multiple vehicle systems that may require heat for operation, require cooling to reject heat, or require operation within specified temperature ranges. As vehicle propulsion transitions away from a single form of vehicle propulsion based solely on conventional internal combustion engines (ICEs) toward a wider array of choices including more electrically dominant systems such as plug-in hybrid electric vehicles …


Technology Improvement Pathways To Cost-Effective Vehicle Electrification: Preprint, A. Brooker, M. Thornton, J. Rugh Feb 2010

Technology Improvement Pathways To Cost-Effective Vehicle Electrification: Preprint, A. Brooker, M. Thornton, J. Rugh

Publications (T)

Electrifying transportation can reduce or eliminate dependence on foreign fuels, emission of green house gases, and emission of pollutants. One challenge is finding a pathway for vehicles that gains wide market acceptance to achieve a meaningful benefit. This paper evaluates several approaches aimed at making plug-in electric vehicles (EV) and plug-in hybrid electric vehicles (PHEVs) cost-effective including opportunity charging, replacing the battery over the vehicle life, improving battery life, reducing battery cost, and providing electric power directly to the vehicle during a portion of its travel. Many combinations of PHEV electric range and battery power are included. For each case, …


Decision Support Tools For Bus Rapid Transit Corridor Planning, Luis David Galicia Jan 2010

Decision Support Tools For Bus Rapid Transit Corridor Planning, Luis David Galicia

Open Access Theses & Dissertations

Bus Rapid Transit (BRT) Systems have been gained popularity in the United States and worldwide as a cost-effective solution of mass transit. There are certain elements and characteristics that such a system should accomplish to be considered a BRT. However, a uniform definition, defined phases to be deployed, and a reliable methodology to estimate ridership are not well structured and clear yet. The purpose of this research was to help BRT stakeholders with an effective method to plan and assess BRT projects. The first goal of this research was to provide a comprehensive description of the essential characteristics of BRT …


Route Change Decision Making By Hurricane Evacuees Facing Congestion, R. Michael Robinson, Asad Khattak Jan 2010

Route Change Decision Making By Hurricane Evacuees Facing Congestion, R. Michael Robinson, Asad Khattak

VMASC Publications

Successful evacuations of metropolitan areas require overcoming unexpected congestion that reduces traffic flows. Congestion may result from accidents, incidents, or other events that reduce road capacity. Traffic professionals and emergency managers may promote deviations from planned routes to bypass an area of congestion and speed mass exit. However, some route changes may actually reduce traffic flow rates, and in these cases decision makers may want to discourage use of alternate routes. By using results of a behavioral survey of potential hurricane evacuees, this study identifies variables associated with the decision to alter routes and also identifies frequently used information sources. …


Investigating The Factors That Influence Injury Severity During Large Truck Crashes, Irina Olegovna Hoag Dec 2009

Investigating The Factors That Influence Injury Severity During Large Truck Crashes, Irina Olegovna Hoag

Civil & Environmental Engineering Theses & Dissertations

Large trucks and passenger cars share the transportation infrastructure. The diversity of mass, size and maneuverability of vehicles on roads makes truck involved collisions very dangerous and causes injury and fatality of drivers and passengers. Considering that large trucks are usually traveling for a long distance and cross country, Large Truck Crash Causation Study (LTCCS) collected data to analyze and predict injury or fatality from a set of predictor (independent) variables. Data were collected at 24 sites in 17 States and 2,284 vehicles were involved in crashes and have up to 1,000 variables for each crash. Sixty-nine percent of these …


A Service Choice Model For Optimizing Taxi Service Delivery, Shih-Fen Cheng, Xin Qu Oct 2009

A Service Choice Model For Optimizing Taxi Service Delivery, Shih-Fen Cheng, Xin Qu

Research Collection School Of Computing and Information Systems

Taxi service has undergone radical revamp in recent years. In particular, significant investments in communication system and GPS devices have improved quality of taxi services through better dispatches. In this paper, we propose to leverage on such infrastructure and build a service choice model that helps individual drivers in deciding whether to serve a specific taxi stand or not. We demonstrate the value of our model by applying it to a real-world scenario. We also highlight interesting new potential approaches that could significantly improve the quality of taxi services.


Developing Corridor-Level Truck Travel Time Estimates And Other Freight Performance Measures From Archived Its Data, Christopher M. Monsere, Michael Wolfe, Heba Alawakiel, Max Taylor Stephens Aug 2009

Developing Corridor-Level Truck Travel Time Estimates And Other Freight Performance Measures From Archived Its Data, Christopher M. Monsere, Michael Wolfe, Heba Alawakiel, Max Taylor Stephens

TREC Final Reports

The objectives of this research were to retrospectively study the feasibility for using truck transponder data to produce freight corridor performance measures (travel times) and real-time traveler information. To support this analysis, weigh-in-motion data from each of the twenty-two stations in Oregon were assembled, processed, and uploaded in the WIM data archive is housed under the Portland Transportation Archive Listing (PORTAL) umbrella at Portland State University’s Intelligent Transportation Systems Lab. Nearly 42,000,000 truck records were successful uploaded to the archive dating back to July 2005. Two separate algorithms necessary for this research were scripted, tested, and validated. The closest stations …


Analysis And Design Of Earthquake Relief Virtual Logistic Information System, Chi Chen Jul 2009

Analysis And Design Of Earthquake Relief Virtual Logistic Information System, Chi Chen

World Maritime University Dissertations

No abstract provided.


Towards A Single European Sky, Yael Gruksha-Cockayne, Bert De Reyck Jun 2009

Towards A Single European Sky, Yael Gruksha-Cockayne, Bert De Reyck

Research Collection Lee Kong Chian School Of Business

We describe an integrated decision-making framework and model that we developed to aid EUROCONTROL, the European air traffic management organization, in its vital role of constructing a single unified European sky. Combining multicriteria decision analysis with large-scale optimization methods, such as integer programming and column generation using branch and price, our model facilitates the process by which the numerous European aviation stakeholders evaluate and select technological enhancements to the European air traffic management system. We consider multiple objectives and potential disagreements by stakeholders regarding the impact of proposed system enhancements and allow for different priorities for each key performance area. …


Environmental Durability Of Reinforced Concrete Deck Girders Strengthened For Shear With Surface Bonded Carbon Fiber-Reinforced Polymer, Christopher Higgins, Matthew R. Dawson, Mikal M. Mitchell, Gautam Sopal, A. Ekin Senturk May 2009

Environmental Durability Of Reinforced Concrete Deck Girders Strengthened For Shear With Surface Bonded Carbon Fiber-Reinforced Polymer, Christopher Higgins, Matthew R. Dawson, Mikal M. Mitchell, Gautam Sopal, A. Ekin Senturk

TREC Final Reports

This research investigated the durability of carbon fiber-reinforced polymer composites (CFRP) used for shear strengthening reinforced concrete deck girders. Large beams were used to avoid accounting for size effects in the data analysis. The effort included determining the role of freeze-thaw, moisture, and fatigue on structural performance and developing analytical design procedures that account for durability.

The results showed that moisture infiltration behind the CFRP, combined with freeze-thaw, was critical in reducing shear panel stiffness and shear capacity. Long-term moisture exposure alone produced only a minor decrease in shear capacity. Freeze-thaw, combined with fatigue, had little effect on shear capacity …


Practical Approximations To Quantify The Impact Of Time Windows And Delivery Sizes On Vmt Multi-Stop Tours, Miguel A. Figliozzi Apr 2009

Practical Approximations To Quantify The Impact Of Time Windows And Delivery Sizes On Vmt Multi-Stop Tours, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

This paper studies approximations to the average length of Vehicle Routing Problems (VRP). The approximations are valuable for strategic and planning analysis of transportation and logistics problems. The research focus is on VRP with varying number of customers, demands, and locations. This modeling environment can be used in transport and logistics models that deal with a distribution center serving an area with daily variations in the demand. The routes are calculated daily based on what freight is available. New approximations and experimental settings are introduced. Average distance travelled is estimated as a function of the number of customers served and …


Implementation Requirements For The Notice Architecture In Vehicular Communications, Dusadee Treeumnuk Apr 2009

Implementation Requirements For The Notice Architecture In Vehicular Communications, Dusadee Treeumnuk

Electrical & Computer Engineering Theses & Dissertations

Many studies have been focusing on Vehicular Ad-Hoc Networking (VANET) in order to increase the quality of traffic and life on the road. An important aspect in vehicular communications is maintaining the privacy and security of VANET. NOTICE is an emerging architecture promising efficient traffic notification as well as strong immunity to malicious attacks, leading to improvement of safety and reduction of traffic congestion on roadways. To enable secure traffic notification, the NOTICE system employs vehicle-to-infrastructure (V2I) communication rather than vehicle-to-vehicle (V2V) communication like in traditional VANET. The infrastructure consists of sensor belts which are embedded in the roadway and …


Application Of Lrfd Geotechnical Principles For Pile Supported Bridges In Oregon: Phase 1, Trevor D. Smith, Peter Dusicka Jan 2009

Application Of Lrfd Geotechnical Principles For Pile Supported Bridges In Oregon: Phase 1, Trevor D. Smith, Peter Dusicka

TREC Final Reports

Bridge foundations must be designed based on acceptable risks of failure. To secure rapid implementation of Load Resistance Factor Design (LRFD) principles for foundation design, the American Association of State Highway and Transportation Officials (AASHTO) and the Federal Highway Administration (FHWA) are requiring their use through AASHTO code. The Bridge Section of the Oregon Department of Transportation (ODOT) has responsibility for satisfactory design of all the bridge structures across the state’s highway system. The widespread geotechnical adoption of the LRFD code throughout state DOTs has been difficult in the case of deep foundations due to regional differences and in some …


Finite Element Modeling Of Nondestructive Test Methods Used For Detection Of Delamination In Hot Mix Asphalt Pavements, Dante Mejia Munoz Jan 2009

Finite Element Modeling Of Nondestructive Test Methods Used For Detection Of Delamination In Hot Mix Asphalt Pavements, Dante Mejia Munoz

Open Access Theses & Dissertations

For the simulation of detection of delamination this study focus on three NDT methods: Impact Echo, Impulse Response and Ultrasonic Surface Waves. The was evaluated and then a parametric study was elaborated.


How Can We Best Manage Freeway Congestion?, Robert Bertini, Christopher Monsere Dec 2008

How Can We Best Manage Freeway Congestion?, Robert Bertini, Christopher Monsere

TREC Project Briefs

Researchers from Portland State University evaluate Oregon’s Implementation of System-Wide Adaptive Ramp Metering (SWARM).


Using Archived Its Data To Measure The Operational Benefits Of A System-Wide Adaptive Ramp Metering System, Robert L. Bertini, Christopher Monsere, Oren Eshel, Soyoung Ahn Dec 2008

Using Archived Its Data To Measure The Operational Benefits Of A System-Wide Adaptive Ramp Metering System, Robert L. Bertini, Christopher Monsere, Oren Eshel, Soyoung Ahn

Civil and Environmental Engineering Faculty Publications and Presentations

A System-Wide Adaptive Ramp Metering (SWARM) system has been implemented in the Portland, Oregon metropolitan area, replacing the previous pre-timed ramp-metering system that had been in operation since 1981. SWARM has been deployed on six major corridors and operates during the morning and afternoon peak hours. This report presents results of a "before" and "after" evaluation of the performance of two freeway corridors as part of ongoing efforts to measure the benefits of the new SWARM system, as compared to the pre-timed system. The study benefited from using the existing regional data, surveillance and communications infrastructure in addition to a …