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• 1. [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

• 2. [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