##### DM-09 - The hexagonal model

- Illustrate the hexagonal model
- Explain the limitations of the grid model compared to the hexagonal model
- Exemplify the uses (past and potential) of the hexagonal model

- Illustrate the hexagonal model
- Explain the limitations of the grid model compared to the hexagonal model
- Exemplify the uses (past and potential) of the hexagonal model

- Describe how to generate a unique TIN solution using Delaunay triangulation
- Describe the architecture of the TIN model
- Construct a TIN manually from a set of spot elevations
- Delineate a set of break lines that improve the accuracy of a TIN
- Describe the conditions under which a TIN might be more practical than GRID
- Demonstrate the use of the TIN model for different statistical surfaces (e.g., terrain elevation, population density, disease incidence) in a GIS software application

- Illustrate the quadtree model
- Describe the advantages and disadvantages of the quadtree model for geographic database representation and modeling
- Describe alternatives to quadtrees for representing hierarchical tessellations (e.g., hextrees, rtrees, pyramids)
- Explain how quadtrees and other hierarchical tessellations can be used to index large volumes of raster or vector data
- Implement a format for encoding quadtrees in a data file

- Describe how to generate a unique TIN solution using Delaunay triangulation
- Describe the architecture of the TIN model
- Construct a TIN manually from a set of spot elevations
- Delineate a set of break lines that improve the accuracy of a TIN
- Describe the conditions under which a TIN might be more practical than GRID
- Demonstrate the use of the TIN model for different statistical surfaces (e.g., terrain elevation, population density, disease incidence) in a GIS software application

- Illustrate the hexagonal model
- Explain the limitations of the grid model compared to the hexagonal model
- Exemplify the uses (past and potential) of the hexagonal model

- Illustrate the quadtree model
- Describe the advantages and disadvantages of the quadtree model for geographic database representation and modeling
- Describe alternatives to quadtrees for representing hierarchical tessellations (e.g., hextrees, rtrees, pyramids)
- Explain how quadtrees and other hierarchical tessellations can be used to index large volumes of raster or vector data
- Implement a format for encoding quadtrees in a data file

- Describe how to generate a unique TIN solution using Delaunay triangulation
- Describe the architecture of the TIN model
- Construct a TIN manually from a set of spot elevations
- Delineate a set of break lines that improve the accuracy of a TIN
- Describe the conditions under which a TIN might be more practical than GRID
- Demonstrate the use of the TIN model for different statistical surfaces (e.g., terrain elevation, population density, disease incidence) in a GIS software application

## DM-11 - Hierarchical data models