Where are we

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Where are we?
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Overview

• Where have we been?
• Where are we going?

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Where have we been?

• Started with understanding what a raster image is
• An array of cells with values (attributes)
• Spent some time digitizing (converting) map data
  to Rasters
• so you could see the problems that might occur
  when automatic conversion from vector to raster
  takes place.
• And to drive home the structure of raster data

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And then banged you heads on

• Started learning the IDRISI system
• Environment
• Display palettes
• Import
• DEM
• Slope and aspect
• Calculator
• Overlay _ etc.

• Modeler
• Extract
• Assign
• Convert
• Reclass

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Via Solving Problems

• Site Selection
• A very, very common process in GIS applications
• Exercises designed to teach you the modules
  listed above
• Use of BOOLEANS very common
• Not always LOGICICAL combinations
• The second PP is a real application of using a
  slightly different way Weighting.
• Exercise 7 is another site selection problem

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Then on to

• Ex 7 --Viewshed
• Use to solve problem of locating microwave towers
• Viewshed over elevation?

• Uses
• Initial
• Update
• Boolean processing
• Collections

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More

• Ex 8 Watershed Hydrology (new)
• Ex 9 Cost and Pathway
• Pipeline planning
• Gas Co. wants to build with one set of criteria
• EMC wants to add some criteria
• Uses DISTANCE for criteria like
• No pipe line through lake or wetlands
• Stay away from residential parcels
• Stay away from shallow soils
• Stay near the roads
• Ex 10 The dam problem