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• 11. [Article] A Proposed Method of Transportation Feature Identification

  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 ...

  Citation × Citation Citation Abstract Copy Title: A Proposed Method of Transportation Feature Identification Author: Butler, J. Allison, Dueker, Kenneth Year: 1998 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 an unambiguously identified set of transportation features and a means of locating related features and attributes on or adjacent to the transportation features. For linear transportation features, the common location referencing system (LRS) is also linear. Usually based on milepoint offsets from a beginning point, linear LRSs are widely used by transportation agencies to locate data stored in numerous legacy databases. Some agencies may have multiple linear LRSs for various applications or topical areas. Data users unfamiliar with linear LRSs have difficulty using highway data provided by transportation agencies, and the correlation of linear and non-linear LRSs is generally quite difficult. The result is that sharing of digital road map databases within and among organizations is difficult since there are no consistent ways of representing transportation features, and different decision rules exist as to what features to include and how they are identified. Numerous efforts are underway to develop a national standard for linear LRS design and implementation, including a set of field procedures to ensure that needed accuracy is achieved. This paper will describe a means to unambiguously define transportation features using a simple set of naming rules. These rules will support linear and other forms of LRS for all types of transportation features, including airports, seaports, railroads, highways, transit services, bridges, intersections, signs, and related facilities and services. Such features may be displayed at multiple scales as point, line, and area graphical objects. Title: A Proposed Method of Transportation Feature Identification Author: Butler, J. Allison, Dueker, Kenneth Year: 1998 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 an unambiguously identified set of transportation features and a means of locating related features and attributes on or adjacent to the transportation features. For linear transportation features, the common location referencing system (LRS) is also linear. Usually based on milepoint offsets from a beginning point, linear LRSs are widely used by transportation agencies to locate data stored in numerous legacy databases. Some agencies may have multiple linear LRSs for various applications or topical areas. Data users unfamiliar with linear LRSs have difficulty using highway data provided by transportation agencies, and the correlation of linear and non-linear LRSs is generally quite difficult. The result is that sharing of digital road map databases within and among organizations is difficult since there are no consistent ways of representing transportation features, and different decision rules exist as to what features to include and how they are identified. Numerous efforts are underway to develop a national standard for linear LRS design and implementation, including a set of field procedures to ensure that needed accuracy is achieved. This paper will describe a means to unambiguously define transportation features using a simple set of naming rules. These rules will support linear and other forms of LRS for all types of transportation features, including airports, seaports, railroads, highways, transit services, bridges, intersections, signs, and related facilities and services. Such features may be displayed at multiple scales as point, line, and area graphical objects. Close

• 12. [Article] A Framework for GIS-T Data Sharing

  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 ...

  Citation × Citation Citation Abstract Copy Title: A Framework for GIS-T Data Sharing Author: Dueker, Kenneth, Butler, J. Allison Year: 2000 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 establishment of a schema for transportation features and their identifiers. An underlying principle is the need for a common data model that holds transportation features—not their graphical representations—as the objects of interest. Attributes of transportation features are represented as linear and point events that are located along the feature using linear referencing. Sharing of transportation data involves exchange of relevant transportation features and events, not links and nodes of application-specific databases. Strategies for the sharing of transportation features follow from this approach. The key strategy is to identify features in the database to facilitate a transactional update system, one that does not require rebuilding the entire database anew. This feature-oriented enterprise GIS-T database becomes the basis for building separate application-specific network databases. Title: A Framework for GIS-T Data Sharing Author: Dueker, Kenneth, Butler, J. Allison Year: 2000 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 establishment of a schema for transportation features and their identifiers. An underlying principle is the need for a common data model that holds transportation features—not their graphical representations—as the objects of interest. Attributes of transportation features are represented as linear and point events that are located along the feature using linear referencing. Sharing of transportation data involves exchange of relevant transportation features and events, not links and nodes of application-specific databases. Strategies for the sharing of transportation features follow from this approach. The key strategy is to identify features in the database to facilitate a transactional update system, one that does not require rebuilding the entire database anew. This feature-oriented enterprise GIS-T database becomes the basis for building separate application-specific network databases. Close

• 13. [Article] Analysis of Design Attributes and Crashes on the Oregon Highway System

  Since the passage of the Highway Safety Act of 1966, state departments of transportation have engaged in systematic safety improvement planning and programming. According to Davis (2000), the general approach ...

  Citation × Citation Citation Abstract Copy Title: Analysis of Design Attributes and Crashes on the Oregon Highway System Author: Strathman, James G., Dueker, Kenneth, Zhang, Jihong, Williams, Timothy Year: 2001 Since the passage of the Highway Safety Act of 1966, state departments of transportation have engaged in systematic safety improvement planning and programming. According to Davis (2000), the general approach to safety improvement planning employed by most states follows six principal steps: 1. Identification of hazardous roadway locations using crash records; 2. Detailed engineering study of selected hazardous locations to identify roadway design problems; 3. Identification of potential countermeasures; 4. Assessment of the costs and benefits of potential countermeasures; 5. Implementation of countermeasures with the highest net benefits; 6. Assessment of countermeasure effectiveness following implementation. All planning processes are subject to uncertainty. In safety improvement planning, the determination of benefits from implementation of countermeasures depends greatly on projected crash reductions. Such projections are acknowledged to be the most uncertain element of the safety planning process (Pfefer et al., 1999). More than 25 years ago Laughland et al. (1975) identified the need for development of a national comprehensive set of crash reduction factors (CRFs) that states could employ in evaluating safety countermeasures. However, this need has not been addressed, and is not likely to be pursued (FHWA, 1991). As a result, states have been responsible for developing their own CRFs. Title: Analysis of Design Attributes and Crashes on the Oregon Highway System Author: Strathman, James G., Dueker, Kenneth, Zhang, Jihong, Williams, Timothy Year: 2001 Since the passage of the Highway Safety Act of 1966, state departments of transportation have engaged in systematic safety improvement planning and programming. According to Davis (2000), the general approach to safety improvement planning employed by most states follows six principal steps: 1. Identification of hazardous roadway locations using crash records; 2. Detailed engineering study of selected hazardous locations to identify roadway design problems; 3. Identification of potential countermeasures; 4. Assessment of the costs and benefits of potential countermeasures; 5. Implementation of countermeasures with the highest net benefits; 6. Assessment of countermeasure effectiveness following implementation. All planning processes are subject to uncertainty. In safety improvement planning, the determination of benefits from implementation of countermeasures depends greatly on projected crash reductions. Such projections are acknowledged to be the most uncertain element of the safety planning process (Pfefer et al., 1999). More than 25 years ago Laughland et al. (1975) identified the need for development of a national comprehensive set of crash reduction factors (CRFs) that states could employ in evaluating safety countermeasures. However, this need has not been addressed, and is not likely to be pursued (FHWA, 1991). As a result, states have been responsible for developing their own CRFs. Close

• 14. [Article] Development of a Statistical Algorithm for the Real-Time Prediction of Transit Vehicle Arrival Times Under Adverse Conditions

  Prior TransNow funded research by Portland State University (PSU) and the University of Washington (UW) in cooperation with Tri-Met, the transit provider for the Portland metropolitan area, has utilized ...

  Citation × Citation Citation Abstract Copy Title: Development of a Statistical Algorithm for the Real-Time Prediction of Transit Vehicle Arrival Times Under Adverse Conditions Author: Dueker, Kenneth, Kimpel, Thomas J., Strathman, James G. Year: 2001 Prior TransNow funded research by Portland State University (PSU) and the University of Washington (UW) in cooperation with Tri-Met, the transit provider for the Portland metropolitan area, has utilized a rich set of archived data from the Automatic Vehicle Location (AVL)-based Bus Dispatch System (BDS). Tri-Met is one of the few transit agencies that archive AVL data for analysis and research. Title: Development of a Statistical Algorithm for the Real-Time Prediction of Transit Vehicle Arrival Times Under Adverse Conditions Author: Dueker, Kenneth, Kimpel, Thomas J., Strathman, James G. Year: 2001 Prior TransNow funded research by Portland State University (PSU) and the University of Washington (UW) in cooperation with Tri-Met, the transit provider for the Portland metropolitan area, has utilized a rich set of archived data from the Automatic Vehicle Location (AVL)-based Bus Dispatch System (BDS). Tri-Met is one of the few transit agencies that archive AVL data for analysis and research. Close

• 15. [Article] Appraisal of University-Based Research in Urban Transportation

  University-based research in transportation, particularly urban transportation is in disarray. This disarray stems from a major decline in research funding in real terms available to universities and from ...

  Citation × Citation Citation Abstract Copy Title: Appraisal of University-Based Research in Urban Transportation Author: Dueker, Kenneth, Beimborn, Edward, Edner, Sheldon Year: 1987 University-based research in transportation, particularly urban transportation is in disarray. This disarray stems from a major decline in research funding in real terms available to universities and from a lack of a consistent policy and practice with respect to research in transportation. As a result, university researchers are pursuing new options for both basic and applied research in transportation. This paper sets forth issues involved in developing university-based research programs in transportation. Particularly, it argues for a more open and peer review based process for a basic transportation research program. This paper provides a context for needed assessment of the university role in such research. The effort should also include u.s. DOT and TRB. There is also a need to distinguish among basic and policy research, training, and technology transfer and provide coherent programs for each. Title: Appraisal of University-Based Research in Urban Transportation Author: Dueker, Kenneth, Beimborn, Edward, Edner, Sheldon Year: 1987 University-based research in transportation, particularly urban transportation is in disarray. This disarray stems from a major decline in research funding in real terms available to universities and from a lack of a consistent policy and practice with respect to research in transportation. As a result, university researchers are pursuing new options for both basic and applied research in transportation. This paper sets forth issues involved in developing university-based research programs in transportation. Particularly, it argues for a more open and peer review based process for a basic transportation research program. This paper provides a context for needed assessment of the university role in such research. The effort should also include u.s. DOT and TRB. There is also a need to distinguish among basic and policy research, training, and technology transfer and provide coherent programs for each. Close

• 16. [Article] Portland's Changing Landscape

  Occasional Papers in Geography Publication No. 4 What is the nature and character of Portland? What are the conditions, changes and developments that have made it what it is? How does Portland compare ...

  Citation × Citation Citation Abstract Copy Title: Portland's Changing Landscape Author: Price, Larry W., Johnson, Daniel M., Ashbaugh, James A., Dotterrer, Steve, Abbott, Carl, Poulsen, Thomas M., Lycan, Richard, Latz, Gil, Dueker, Kenneth, Edner, Sheldon, Rabiega, William A., Kale, Steven R., Corcoran, Patrick E., Vanselow, Glenn, Hamilton, F. E. Ian, Chapman, Nancy J., Starker, Joan Year: 1987 Occasional Papers in Geography Publication No. 4 What is the nature and character of Portland? What are the conditions, changes and developments that have made it what it is? How does Portland compare with other places? What makes it unique? These are some of the question pursued in this volume. This book contains thirteen chapters discussing various facets of Portland's environmental, economy, and character. It is an up-to-date and comprehensive analysis of dynamics and change in the landscape. An overview is provided of Portland as a city and place to live, as well as its functional significance on a national and international basis. Two threads are woven through the tapestry of these essays. One is that Portland is a big city but with many attributes of a small town. The other is the closeness and accessibility of city and nature. The challenge is how to nurture and maintain both - to have our cake and eat it too. The evidence is clear that most American cities have not been able to achieve this. Only the future can tell how Portland will fare. The authors are all professional geographers or work in closely related fields. All have been involved with the Portland scene for a number of years and are uniquely qualified to write about these topics. While each approaches problems from his or her own perspective, the net result is a summing up, a taking stock of where we have been and where we are going. When considered as a whole the book should provide a better view than we have had of the nature and character of this special place. Title: Portland's Changing Landscape Author: Price, Larry W., Johnson, Daniel M., Ashbaugh, James A., Dotterrer, Steve, Abbott, Carl, Poulsen, Thomas M., Lycan, Richard, Latz, Gil, Dueker, Kenneth, Edner, Sheldon, Rabiega, William A., Kale, Steven R., Corcoran, Patrick E., Vanselow, Glenn, Hamilton, F. E. Ian, Chapman, Nancy J., Starker, Joan Year: 1987 Occasional Papers in Geography Publication No. 4 What is the nature and character of Portland? What are the conditions, changes and developments that have made it what it is? How does Portland compare with other places? What makes it unique? These are some of the question pursued in this volume. This book contains thirteen chapters discussing various facets of Portland's environmental, economy, and character. It is an up-to-date and comprehensive analysis of dynamics and change in the landscape. An overview is provided of Portland as a city and place to live, as well as its functional significance on a national and international basis. Two threads are woven through the tapestry of these essays. One is that Portland is a big city but with many attributes of a small town. The other is the closeness and accessibility of city and nature. The challenge is how to nurture and maintain both - to have our cake and eat it too. The evidence is clear that most American cities have not been able to achieve this. Only the future can tell how Portland will fare. The authors are all professional geographers or work in closely related fields. All have been involved with the Portland scene for a number of years and are uniquely qualified to write about these topics. While each approaches problems from his or her own perspective, the net result is a summing up, a taking stock of where we have been and where we are going. When considered as a whole the book should provide a better view than we have had of the nature and character of this special place. Close

• 17. [Article] Automated Bus Dispatching, Operations, Control, and Service Reliability: Baseline Analysis

  The authors of this report are engaged in a long term project to assess the impacts of Tri-Met's BDS on service reliability and transit use. The framework designed for this assessment focuses on documenting ...

  Citation × Citation Citation Abstract Copy Title: Automated Bus Dispatching, Operations, Control, and Service Reliability: Baseline Analysis Author: Strathman, James G., Dueker, Kenneth, Kimpel, Thomas J., Gerhart, Rick, Turner, Ken, Taylor, Pete, Callas, Steve, Griffin, David, Hopper, Janet Year: 1998 The authors of this report are engaged in a long term project to assess the impacts of Tri-Met's BDS on service reliability and transit use. The framework designed for this assessment focuses on documenting service reliability and passenger activity at three major junctures: • The pre-operational (baseline) period; • The initial (passive) period following implementation of the new system, when both drivers and dispatchers have access to schedule adherence information in real time, but before the development and use of operations control practices that exploit the information generated by the system; • Full implementation, when operations control practices are defined and actively employed by dispatchers and field supervisors, and when performance data is used in wriling schedules. The baseline analysis documents service reliability on eight routes that were selected to be representative of the typology of routes in Tri-Met's system. Data on weekday run times, headways, and on-time performance were recovered over a two week period in November 1996. Findings from analysis of these data are presented in this report. Title: Automated Bus Dispatching, Operations, Control, and Service Reliability: Baseline Analysis Author: Strathman, James G., Dueker, Kenneth, Kimpel, Thomas J., Gerhart, Rick, Turner, Ken, Taylor, Pete, Callas, Steve, Griffin, David, Hopper, Janet Year: 1998 The authors of this report are engaged in a long term project to assess the impacts of Tri-Met's BDS on service reliability and transit use. The framework designed for this assessment focuses on documenting service reliability and passenger activity at three major junctures: • The pre-operational (baseline) period; • The initial (passive) period following implementation of the new system, when both drivers and dispatchers have access to schedule adherence information in real time, but before the development and use of operations control practices that exploit the information generated by the system; • Full implementation, when operations control practices are defined and actively employed by dispatchers and field supervisors, and when performance data is used in wriling schedules. The baseline analysis documents service reliability on eight routes that were selected to be representative of the typology of routes in Tri-Met's system. Data on weekday run times, headways, and on-time performance were recovered over a two week period in November 1996. Findings from analysis of these data are presented in this report. Close

• 18. [Article] Bus Transit Operations Control: Review and an Experiment Involving Tri-Met’s Automated Bus Dispatching System

  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 ...

  Citation × Citation Citation Abstract Copy Title: Bus Transit Operations Control: Review and an Experiment Involving Tri-Met’s Automated Bus Dispatching System Author: Strathman, James G., Kimpel, Thomas J., Dueker, Kenneth Year: 2000 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 in-vehicle travel time, longer waiting time at stops, and greater uncertainty. This paper has two overall purposes. First, it provides a review of operations control principles and practices reported in the literature. Second, it reports the results of an operations control experiment whose objective was to maintain headways, or the time separation between buses on a route. The experiment was developed to explore a possible application of the automated Bus Dispatching System (BDS) recently implemented by Tri-Met, the transit provider for the Portland, Oregon, metropolitan region. Title: Bus Transit Operations Control: Review and an Experiment Involving Tri-Met’s Automated Bus Dispatching System Author: Strathman, James G., Kimpel, Thomas J., Dueker, Kenneth Year: 2000 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 in-vehicle travel time, longer waiting time at stops, and greater uncertainty. This paper has two overall purposes. First, it provides a review of operations control principles and practices reported in the literature. Second, it reports the results of an operations control experiment whose objective was to maintain headways, or the time separation between buses on a route. The experiment was developed to explore a possible application of the automated Bus Dispatching System (BDS) recently implemented by Tri-Met, the transit provider for the Portland, Oregon, metropolitan region. Close

• 19. [Article] 1988 Oregon Public Transportation Study

  Oregon continues to face challenges in public transportation. The lack of a consistent and comprehensive framework of state policy is making local efforts to meet public transportation demands harder and ...

  Citation × Citation Citation Abstract Copy Title: 1988 Oregon Public Transportation Study Author: Edner, Sheldon, Dueker, Kenneth, Dean, Janice Year: 1989 Oregon continues to face challenges in public transportation. The lack of a consistent and comprehensive framework of state policy is making local efforts to meet public transportation demands harder and fails to exploit economic and transportation opportunities for improving the vitality of the state. The absence of continuous and stable state financial assistance has weakened the state/local partnership in providing public transportation services and kept mobility for many Oregonians at a minimal level. Finally, as the federal role in funding transportation declines the need for aggressive state leadership increases. The following recommendations for Legislative and Executive action are offered as incremental steps towards meeting Oregon's public transportation challenge: Authorize additional funding for special needs transportation by increasing the revenues to the Special Transportation Fund. Authorize and fund an annual, stable capital assistance program for public transportation providers equivalent to the funding level of the past biennium. Provide greater flexibility of local public transportation option funding through authorization of new local revenue sources. Authorize and fund an expanded administrative role for the ODOT Public Transit Division to provide technical assistance, establish standards and monitor public transportation provider performance, administer state capital assistance to providers, and promote cooperation and coordination between transportation providers. Adopt as a statewide policy goal, cooperation among modal transportation agencies to achieve efficient and coordinated use of scarce resources. Adopt as a statewide policy goal, cooperation among public transportation programs and economic development programs in order to make Oregon an attractive and profitable location for industry. Adopt as a statewide policy goal, the coordination of services and resources among agencies that support public transportation and human service transportation. Create incentives for local land use guidelines that promote integration of transportation planning into existing and future land use policies. Title: 1988 Oregon Public Transportation Study Author: Edner, Sheldon, Dueker, Kenneth, Dean, Janice Year: 1989 Oregon continues to face challenges in public transportation. The lack of a consistent and comprehensive framework of state policy is making local efforts to meet public transportation demands harder and fails to exploit economic and transportation opportunities for improving the vitality of the state. The absence of continuous and stable state financial assistance has weakened the state/local partnership in providing public transportation services and kept mobility for many Oregonians at a minimal level. Finally, as the federal role in funding transportation declines the need for aggressive state leadership increases. The following recommendations for Legislative and Executive action are offered as incremental steps towards meeting Oregon's public transportation challenge: Authorize additional funding for special needs transportation by increasing the revenues to the Special Transportation Fund. Authorize and fund an annual, stable capital assistance program for public transportation providers equivalent to the funding level of the past biennium. Provide greater flexibility of local public transportation option funding through authorization of new local revenue sources. Authorize and fund an expanded administrative role for the ODOT Public Transit Division to provide technical assistance, establish standards and monitor public transportation provider performance, administer state capital assistance to providers, and promote cooperation and coordination between transportation providers. Adopt as a statewide policy goal, cooperation among modal transportation agencies to achieve efficient and coordinated use of scarce resources. Adopt as a statewide policy goal, cooperation among public transportation programs and economic development programs in order to make Oregon an attractive and profitable location for industry. Adopt as a statewide policy goal, the coordination of services and resources among agencies that support public transportation and human service transportation. Create incentives for local land use guidelines that promote integration of transportation planning into existing and future land use policies. Close