Final Exam. Digital Compilation and Database Design (Fall 2004)

Answer three out of five questions. The first question needs to be answered by everyone. Select one from 2 and 3 and another one from 4 and 5.

Make sure you clearly mark which questions you answered. Your answers should be typed and double spaced and any relevant diagram neatly drawn. Please make an effort to be thorough yet concise (no more than two pages per question, not including graphics). Use all resources available to you including texts, manuals, lab exercises, and help files. The exam is due on December 9 by 5 PM.

Required

1. Database design spans three basic stages – conceptual, logical, and physical designs. Arctur and Zeiler (2004) summarized ten steps to implement these three stages in geodatabase designs. Describe the tasks that you undertook for your project for each of these steps. Provide descriptions of the feature layers and data model types that you used, including their topological structures and any other information relevant to understand how these data sets represent reality and are suitable for the intended applications.

Select one from 2 and 3

2. You used a DEM to delineate watersheds in Lab 5 (Task 4, Chapter 12). Describe the steps and algorithms of this method. Your answers should include discussions on how a filled elevation grid, a flow direction grid, a flow accumulation grid, and a drainage network are formed.

3. Density estimation and spatial interpolation are techniques that convert point data into surfaces. Describe the difference between density measurement and interpolation. What are the different methods of spatial interpolation and what does spatial interpolation have to do with Tobler’s First Law of Geography? Which spatial interpolation method will you use? Why?

Select one from 4 and 5

4. The object-oriented design of ArcGIS Geodatabase has fundamental differences from the integrated coverage concept used in the coverage data structure in handling complex geometric objects such as regions or routes. Describe the concept of integrated coverage and how it handles regions and routes in contrast to the Geodatabase approach.

5. ArcGIS Geodatabase provides 26 topological rules (4 for points, 12 for lines, 9 for polygons, and 1 for both lines and polygons) for creating geometric relationships between features and feature classes. Describe how topologies are built in Geodatabase. Include discussions on cluster tolerance, ranking, cracking, clustering, and validating. Select and describe 4 topological rules and give examples of when they could be used.