1. TIN: Triangulated Irregular Network – Represents surface with vector data using irregularly distributed nodes which hold three dimensional coordinates (X,Y, and Z). Nodes are distributed variably based on the Douglas Polgor algorithm which determins which points are most neccessary to an accurate representation of the terrain. “http://en.wikipedia.org/wiki/Triangulated_irregular_network”
3. Mass Points: an irregularly distributed mass of points with x,y, and z coordinates used to capture the important variations in the shape of the surface being modeled. “http://en.mimi.hu/gis/mass_point.html”
5. Contiguous data: similar data stored adjacently in cells. (?)
7. Raster: Data that is organized in a grid/matrix with rows and columns to represent thematic data with qualitative value such as land use, soils, streams, and elevation.
9. Zone: A group(zone) of similar data
11. Resolution: Refers to the size and number of screen pixels, typicaly higher resolution is found when the size of pixels decrease, and the number of pixels increase. “http://en.mimi.hu/gis/resolution.html”
13. Triangulation: The accurate surveying of very large triangles called triangulation networks. “http://en.mimi.hu/gis/triangulation.html”
15. Z-values: The elevation value of a surface at a specific X, and Y coordinate. Also known as Spot Value.
17. Slope: The measurement of how steep the ground surface is. The steeper the surface the greater the slope. Slope is measured by calculating the tangent of the surface. The tangent is calculated by dividing the vertical change in elevation by the horizontal distance. “http://www.geom.unimelb.edu.au/gisweb/DEMModule/DEM_T_Sl.htm“
19. Elevation: Elevation, is mainly used when referring to points on the Earth’s surface, while altitude is used for points above the surface, such as an aircraft in flight or a spacecraft in orbit, and depth is used for points below the surface. “http://en.wikipedia.org/wiki/Elevation“
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