In the previous chapters we have seen how a wide variety of types of geographic data can be created and stored. Methods of digitizing and scanning allow geographic data to be created from paper maps and photographs. Powerful computing hardware makes it possible to store large amounts of data in forms that are readily amenable to manipulation and analysis using the routines stored in powerful so...

This paper deals with issues arising from a central theme in contemporary computer modeling – visualization. We first tie visualization to varieties of modeling along the continuum from iconic to symbolic and then focus on the notion that our models are so intrinsically complex that there are many different types of visualization that might be developed in their understanding and implementation...

This paper investigates the processing of spatial queries with topological constraints, for which current database solutions are inappropriate. Topological relations, such as disjoint, meet, overlap, inside, and contains, have been well defined by the 9-intersection, a comprehensive model for binary topological relations. We focus on two types of queries: (1) “Which objects have a stated topolo...

_____________________ Much of this research was conducted under support from the Navigation Economic Technologies (NETS) program of the Institute for Water Resources of the Army Corps of Engineers. We gratefully acknowledge their support and comments. We especially appreciate the comments of Keith Hofseth and Kevin Hendrickson who read early versions of this chapter and provided a number of use...

precise localization of the third molars in relation to the inferior alveolar nerve canal is critical from a clinical point of view and strongly affects the surgical treatment outcome. recently, by using three-dimensional modeling software, the relationship of third molar root apices and inferior alveolar nerve canal can be better understood. in this study, the spatial relationship of two surgi...

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