1. Discussion: Representing the World

2. Discussion Question How much do we know about the world?

3. How “big” is the earth? Surface: ~500,000,000 sq km Age: ~5 billion years Thick? –“Living space”: a few meters to over 2 miles

4. Data Representation Features: –Spatial Data: Points, Polylines, Polygons –Attributes Rasters TINs Volumes Others?

5. Features and Attributes Features Well-defined boundaries in empty space “Desktop littered w/ objects” World littered w/ cars, houses, etc. Counts 49 houses in a subdivision

6. Object Model Identifies “Objects” Objects have “Properties” Similar to “Features” but much more flexible –Can overlap –Can have different properties on each object Much harder to manage! Alternative: Find objects with common attributes and make them features

7. Hierarchical Object Model USA –Colorado –Oregon Corvallis: –OSU »Wilkinson 207 Eugene … Mexico –CONABIO

8. Complex Data Data Models Data Centers –NationalAtlas.gov –EROS Data Center Distributed Data –The Cloud –The accumulated knowledge of humans?