Computer Science and Engineering, Department of


Date of this Version

Fall 11-28-2011

Document Type



A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Computer Science, Under the Supervision of Professor Peter Revesz. Lincoln, Nebraska: November, 2011

Copyright (c) 2011 Anthony B. Ngo


We describe the design and implementation of a traffic crash and snow complaint GIS system developed for the Lincoln Public Works department. We also describe a novel geocoding algorithm that was used to move data from the older Criminal Justice Information System, which is a relational database, to the new GIS system. In addition, we describe the implementation of several indexing algorithms that enable the system to efficiently answer rectangular range queries and queries about the relative locations of moving objects. Finally, in many applications (on-line analysis or mobile GIS), we need to execute spatial query efficiently (fast and small), and to scan through all the existing complex objects (non-zero extent) might be very slow. Thus, we introduce an approximated indexing method, called ApproximatedR-Tree, for improving performance and space over complex objects.

Adviser: Peter Revesz