Urban Studies and Planning Commons^™

Connected Vehicle System Design For Signalized Arterials, Xianfeng Terry Yang, Mingyue Ji, Qinzheng Wang

TREC Final Reports

It can be expected that connected vehicles (CVs) systems will soon go beyond testbed and appear in real-world applications. To accommodate a large number of connected vehicles on the roads, traffic signal control systems on signalized arterials would require supports of various components such as roadside infrastructure, vehicle on-board devices, an effective communication network, and optimal control algorithms. In this project, we aim to establish a real-time and adaptive system for supporting the operations of CV-based traffic signal control functions. The proposed system will prioritize the communication needs of different types of CVs and best utilize the capacity of the …

Fast Track: Allowing Bikes To Participate In A Smart-Transportation System, Stephen Fickas, Marc Schlossberg

TREC Final Reports

This project focuses on a mode of transportation that is currently left out of V2X (vehicle-to-everything) conversations: bicycling. The project demonstrates how university researchers, city traffic engineers, and signal-controller manufacturers can come together to give bicyclists the same technology appearing on modern vehicles: Green Light Optimized Speed Advisory (GLOSA). GLOSA allows motorists to set their speed along corridors to maximize their chances of catching a “green wave” (i.e., not being forced to stop as they travel through the corridor). This project demonstrates how GLOSA can be used by bicyclists in the same way it is used by motorists on a …

Self-Organizing Signals: A Better Framework For Transit Signal Priority, Peter G. Furth

PSU Transportation Seminars

Actuated traffic signal control logic has many advantages because of its responsiveness to traffic demands, short cycles, effective use of capacity leading to and recovering from oversaturation, and amenability to aggressive transit priority. Its main drawback has been its inability to provide good progression along arterials. However, the traditional way of providing progression along arterials, coordinated-actuated control with a common, fixed cycle length, has many drawbacks stemming from its long cycle lengths, inflexibility in recovering from priority interruptions, and ineffective use of capacity during periods of oversaturation. This research explores a new paradigm for traffic signal control, “self-organizing signals,” based …

Using Empirical (Real-World) Transportation Data To Extend Travel Demand Model Capabilities, Michael Mauch

PSU Transportation Seminars

Real-world traffic trends observed in PORTAL and INRIX traffic data are used to expand the performance measures that can be obtained from Portland Metro's travel demand model to include the number of hours of congestion that can be expected during a typical weekday and travel time reliability measures for congested freeway corridors.

Assessment And Refinement Of Real-Time Travel Time Algorithms For Use In Practice, Kristin A. Tufte, Sirisha Murthy Kothuri

TREC Final Reports

The Federal Highway Administration (FHWA) has set a high priority on the use of existing dynamic message signs (DMS) to provide travel time estimates to the public. The Oregon Department of Transportation (ODOT) currently has three DMS in the Portland metropolitan area configured to display travel time information. In the near future, ODOT would like to make travel time estimates available on additional DMS, over the Internet on tripcheck.com and via 511. Travel time estimates are valuable to the traveling public; however, the estimates must be accurate to be useful. The FHWA indicates that 90% accuracy is ideal and suggests …

Building And Maintaining A Statewide Transportation Framework, Kenneth Dueker, Paul Bender

Center for Urban Studies Publications and Reports

Creating and maintaining up-to-date sharable Geographic Information SystemsTransportation (GIS-T) data is challenging. Many states are working on Transportation Framework efforts to build a complete, consistent, and current transportation data layer in conjunction with the NSDI and Geospatial One-Stop efforts. This paper summarizes an effort that systematically re-examined transportation data sharing issues as part of the development of a Transportation Framework for the State of Washington. Business needs were assessed in terms of spatial and temporal accuracy needs of stakeholders and users of a state-wide Transportation Framework. A conceptual model was developed for a Transportation Framework with emphasis on data flows …

Tri-Met's Experience With Automatic Passenger Counter And Automatic Vehicle Location Systems, James G. Strathman

Center for Urban Studies Publications and Reports

The Tri-County Metropolitan Transportation District of Oregon (Tri-Met) is one of about 30 metropolitan transit agencies that have deployed both automatic vehicle location (AVL) and automatic passenger counter (APC) systems (Casey, 1999). These technologies are important components of the agency’s new automated bus dispatching system (BDS). The AVL and APC systems at Tri-Met recover comprehensive operations and passenger activity data at the bus stop level that is archived for later analysis. The agency has gained a reputation as an industry leader in the areas of data archiving and the application of archived data to performance monitoring and analysis.

Prior to …

Evaluation Of Transit Operations: Data Applications Of Tri-Met’S Automated Bus Dispatching System, James G. Strathman, Thomas J. Kimpel, Kenneth Dueker, Rick Gerhart, Steve Callas

Center for Urban Studies Publications and Reports

Over the past decade, the adoption of Advanced Public Transportation System (APTS) technology has been motivated by transit providers’ desire to improve service reliability as well as to identify potential savings from improvements in scheduling and service planning. Casey (2000) reports that Automatic Vehicle Location (AVL) systems, a cornerstone of APTS, have been deployed by 61 transit agencies as of 1998.

Time Point-Level Analysis Of Passenger Demand And Transit Service Reliability, Thomas J. Kimpel, James G. Strathman, Kenneth Dueker

Center for Urban Studies Publications and Reports

This paper provides a framework for analyzing transit service reliability and estimating passenger demand at the time point-level of analysis. It begins with a literature review of passenger demand modeling and transit service reliability analysis, and shows how advances in transportation technologies are producing vast amounts of data that encourage the use of new modeling techniques. Differences between route-level and time point-level demand modeling are discussed. Lastly, the results of the passenger demand and transit service reliability models estimated from Tri-Met BDS data are presented.

A Clearinghouse Approach To Sharing Transportation Gis Data, Kenneth Dueker, J. Allison Butler, Paul Bender, Jihong Zhang

Center for Urban Studies Publications and Reports

Updating and maintaining Geographic Information Systems-Transportation data (GIS-T data) is proving difficult. Different database formats needed to support diverse applications leads to inconsistencies and inaccuracies, and duplication in updating. A clearinghouse approach is recommended for the collection and dissemination of new transportation features that can be segmented in different ways to meet the needs of various applications and inserted to update existing GIS-T databases. The clearinghouse approach is advantageous in that it is based on collecting data about new or changed transportation features once and uses the data many times to update existing databases.

A Framework For Gis-T Data Sharing, Kenneth Dueker, J. Allison Butler

Center for Urban Studies Publications and Reports

This paper develops a framework and principles for sharing of transportation data. The framework is intended to clarify roles among participants, data producers, data integrators, and data users. The principles are intended to provide guidance for the participants. Both the framework and the principles are based on an enterprise GIS-T data model that defines relations among transportation data elements. The data model guards against ambiguities and provides a basis for the development of the framework and principles for sharing of transportation data. There are two central principles. First is the uncoupling of graphics, topology, position, and characteristics. Second is the …

Sharing Transportation Gis Data, Kenneth Dueker, Paul Bender, Jihong Zhang

Center for Urban Studies Publications and Reports

Updating and maintaining Geographic Information Systems-Transportation data (GIS-T data) is proving difficult. Different database formats needed to support diverse applications leads to inconsistencies and inaccuracies, and duplication in updating. Dueker and Butler (1998) have proposed an Enterprise GIS-T data model that unbundles the various components of transportation data (network links, cartography, and attributes) to facilitate generating application-specific networks, and which eases updating and maintenance. However, developers of existing application-specific databases that employ integrated data models that bundle the network link with cartography and attributes are reluctant to step back to an intermediate form for managing their data. Consequently, attention is …

Bus Transit Operations Control: Review And An Experiment Involving Tri-Met’S Automated Bus Dispatching System, James G. Strathman, Thomas J. Kimpel, Kenneth Dueker

Center for Urban Studies Publications and Reports

An operations plan contains information on the provision of transit service, including intended service levels, vehicle availability, and driver schedules. Agency resources would be utilized efficiently if the operations plan could be executed without disruptions in service. When service disruptions occur, the aim of operations control is to optimize system performance given the current state of the system (Wilson et al., 1992). This typically involves actions intended to either return service to schedule or restore headways separating vehicles. Disruptions in service impose costs on transit providers in the form of reduced productivity and on passengers in the form of increased …

A Primer On Gis-T Databases, J. Allison Butler, Kenneth Dueker

Center for Urban Studies Publications and Reports

This paper describes the primary database design approaches that have been and are being used in geographic information system applications for transportation (GIS-T). While not intending to be exhaustive, the paper covers the primary approaches used in federal, state, and local transportation agencies.

Orbit: The Oregon Road Base Information Team Draft Summary Report Ii, Paul Bender, Mark Bosworth, Kenneth Dueker

Center for Urban Studies Publications and Reports

Data sharing among organizations has the potential to 1) decrease long-term costs of obtaining and maintaining data and 2) to facilitate data consistency and accuracy. Consistency includes both completeness and currency, while accuracy includes positional and relative accuracy of transportation features and their attributes, i.e. any data element related to roads or other transportation infrastructure.

ORBIT, the Oregon Road Base Information Team, is an ongoing effort to create an accessible and comprehensive GIS transportation base for use by public and private agencies with shared stewardship through stakeholder partnerships and standards. ORBIT is occurring concurrently with an effort at the national …

Incident Management In Intelligent Transportation Systems, Kaan Ozbay, Pushkin Kachroo

Electrical & Computer Engineering Faculty Research

Since the conception of Intelligent Transportation Systems (ITS) in the 1980s, many transportation researchers have also worked on the development of incident management models and integrated systems for real-time operations. ITS created the required infrastructure for collecting, processing, and managing real-time traffic data that can be used to develop on-line incident management strategies. This book provides the reader with a broad picture of the overall incident management process in the context of ITS along with a quick review of the models and systems developed by numerous researchers worldwide. This book is a direct result of the long-term incident management research …

The Oregon Dot Slow-Speed Weigh-In--Motion (Swim) Project: Final Report, James G. Strathman

Center for Urban Studies Publications and Reports

Weigh-in-motion (WIM) systems have provided an effective means of data collection for pavement research and facility design, traffic monitoring, and weight enforcement for over 40 years. In weight enforcement, WIM systems have been increasingly used to screen potentially overweight vehicles. Vehicles that exceed weight limits as measured on a WIM scale are then weighed on a static scale, which is subject to accuracy standards specified by the National Institute of Standards and Technology (1998). The use of WIM for screening purposes reduces queuing at weigh stations, resulting in considerable savings for both truckers and enforcement agencies. To date, however, WIM …

Orbit: The Oregon Road Base Information Team, A Draft Summary Report, Mark Bosworth, Kenneth Dueker, Philip J. Wuest

Center for Urban Studies Publications and Reports

It is clear that transportation organizations across the nation are integrating GIS into operations at many different levels—from day to day use for data display, to full-scale enterprise level integration for operations, inventory management, research and a variety of other purposes. The cost of building and maintaining a current and accurate GIS database can be substantial within any given organization. For some smaller level organizations—small counties, cities or special districts, the cost of gathering data, organizing it and implementing systems within expensive software on an expensive operating platform can be downright discouraging. Also, as more complex data structures are accumulated …

A Proposed Method Of Transportation Feature Identification, J. Allison Butler, Kenneth Dueker

Center for Urban Studies Publications and Reports

Geographic information systems (GIS) are being increasingly deployed by transportation agencies to help them display, review, and utilize data. The primary items of interest are transportation facilities and services, which may take the form of highways, airports, bus routes, and seaports, among others. Using GIS software, transportation facilities are represented as geometric shapes; i.e., points, lines, and areas. However, it is increasingly apparent to GIS users in the field of transportation that a geometry-based approach is not sufficient.

The offered solution is to develop a feature-based GIS approach for transportation. The central requirement of such an approach is to have …

Issues In The Design Of A Stop-Level Transit Patronage Model, James G. Strathman, Kenneth Dueker, Zhongren Peng

Center for Urban Studies Publications and Reports

Tri-Met, the transit agency serving the Portland, Oregon metropolitan area is implementing a new bus dispatching system (BDS) that includes automated vehicle location (AVL) technology. An important objective in the agency's decision to invest in a new dispatching system was to maintain or improve service reliability in an urban environment characterized by rapid growth and worsening traffic congestion.

Oregon Dot Slow-Speed Weigh-In-Motion (Swim) Project: Analysis Of Initial Weight Data, Tim Swope, James G. Strathman

Center for Urban Studies Publications and Reports

This report presents the results of a preliminary analysis of axle weights from the Oregon DOT Slow-Speed Weigh in Motion (SWIM) scale at the Wyeth weigh station.* This report includes an analysis of methodology and variables used in the study; estimates of accuracy and precision of the WIM readings; and a regression analysis of the WIM and static scale weighings. Axles weights were collected from the traffic stream.

Least-Cost Transportation Planning In Odot: Feasability Report, Anthony M. Rufolo, Lois M. Bronfman, James G. Strathman

Center for Urban Studies Publications and Reports

Least Cost Planning or Integrated Resource Planning is used in the electric utility industry to broaden the scope of choices to meet service requirements. This typically includes methods to reduce the demand for electricity as well as the more traditional electric generation options. Techniques have been developed to compare the cost of electricity generation with the cost of meeting service requirements by reducing electricity usage. In addition to cost considerations, utilities typically take account of uncertainty associated with forecasts and a variety of other considerations in specifying their least cost plan.

Site Location Study For An Integrated Traffic Data Collection System: Phase 1 Report, Kenneth Dueker, Richard Ledbetter, Bruce Rex

Center for Urban Studies Publications and Reports

Improved technology for counting, classifying, and weighing vehicles in the highway traffic stream is becoming increasingly available. Research has been undertaken to make effective use of these new technologies, not just to replace current data collection programs of counting, classifying, and weighing with more efficient versions. This reports on the Phase I research, which had three major objectives;

• a literature review to guide the analysis of alternative methods;
• a statement of requirements to modernize and integrate the data collection programs of traffic counting, vehicle classification and truck weights, and to identify the type and use of traffic data for design, …

An Evaluation Of Automatic Passenger Counters: Validation, Sampling, And Statistical Inference, James G. Strathman

Center for Urban Studies Publications and Reports

While automatic passenger counters (APC's) offer the potential for cait effective data recovery and management, they also introduce new complications in the data recovery process. This report addresses three issues associated with the implementation of APC's, based on an evaluation of the recent experiences of the Tri-County Metropolitan Transportation District of Oregon (Tri-Met). First is the issue of validation, which is concerned with both the recovery and accuracy of APC passenger data. The second issue concerns the development of a sampling methodology for APC's compatible with UMTA's Section 15 reporting requirements. Third is the issue of inferring system-level ridership from …