Uluğ, Kerem Ali2016-01-082016-01-082008http://hdl.handle.net/11693/14731Ankara : The Department of Computer Engineering and the Institute of Engineering and Science of Bilkent University 2008.Thesis (Master's) -- Bilkent University, 2008.Includes bibliographical references leaves 55-57.Many systems, such as in-car GPS devices and airline company web sites, provide route information between locations. Although such systems are used widely and can provide route information successfully, users of these systems cannot contribute to the data entry process. In these systems, data is entered by the administrators and these systems cannot take advantage of the route expertise of their users. In this work, we present a collaborative system, which provides routes between locations upon user queries. The data in the system is entered by the users of the system. We present a model which is containing locations, links between locations and relationships between locations (containment, neighborhood and intersection) in order to store the data. For the route finding purpose, we present a customized version of the A* search algorithm. This customized version, named A*CD (A* for Collaborative Data), uses heuristics for estimating the cost remaining to the target location while processing the nodes. A*CD can also provide alternative routes, exclude certain link types in the searches according to user preferences and handle the problems associated with multiple stop transportation lines. As the cost models, we use duration and financial cost. We also present the intuitive connections concept. Even if a route does not exist between the selected locations, the system can provide a route with missing links. The gap(s) between the disconnected locations are filled by the help of the relationships between locations. In order to evaluate the performance of the A*CD algorithm, we present automated tests. These tests show that the costs of the routes that are provided by the A*CD algorithm are close to the actual shortest routes. In order to demonstrate the intuitive connections concept, we also present manual test queries.vii, 90 leavesEnglishinfo:eu-repo/semantics/openAccessHeuristic searchCollaborative systemsA* searchTK5105.5 .U48 2008Computer networks.Routers (Computer networks)Human-computer interaction.Heuristic programming.Local transit Data processing.ThesisBILKUTUPB109244