Intro to GIS

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					                             (Geographic Information Systems)

                           An Introduction
                                           Ron Briggs
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                                   GIS--What is it?
                   No easy answer anymore!
       • Geographic Information
             – information about places on the earth’s surface
             – knowledge about “what is where when”
                                               (Don’t forget time!)
       • Geographic Information Technologies
             – technologies for dealing with this information
                   • Global Positioning Systems (GPS)
                   • Remote Sensing (RM)
                   • Geographic Information Systems (GIS)
       • GIS--what’s in the S?
             – Systems: the technology
             – Science: the concepts and theory
             – Studies: the societal context
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
        Geographic Information Technologies
   • Global Positioning Systems (GPS)
         – a system of earth-orbiting satellites which can provide precise
           (100 meter to sub-cm.) location on the earth’s surface (in
           lat/long coordinates or equiv.)
   • Remote Sensing (RS)
         – use of satellites (and aircraft) to capture information about the
           earth’s surface
   • Geographic Information Systems (GISy)
         – at a minimum, comprises a capability for input, storage,
           manipulation and output of geographic information

      GPS and RM are sources of input data for a GISy.
      A GISy provides for storing and manipulating GPS and RS data.
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
               GI Systems, Science and Studies
   • Systems
         – technology for the acquisition and management of spatial
   • Science
         – comprehending the underlying conceptual issues of
           representing data and processes in space-time
         – the science (or theory and concepts) behind the technology
   • Studies
         – understanding the social, legal and ethical issues associated
           with the application of GISy and GISc

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                       Which GIS will we do?
                                 Systems: GIS=GISy
        • Focus on the technology system
        • introduce enough of the science to apply the
          systems correctly and understand their
          capabilities and limitations
        • discuss societal implications primarily in POEC
          6383 (Management and Implementation of GIS),
          and POEC 6381 (Intro to GIS) as they arise
        • combine hands-on technical training with broader
          education, and an emphasis on multidisciplinary
                                               Let’s begin…….
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                                               Changing Domain of GIS



       Source: Forer and Unwin, 1998
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                             Why Study GIS?
 • 80% of local government activities estimated to be geographically based
      – plats, zoning, public works (streets, water supply, sewers), garbage collection, land
        ownership and valuation
 • a significant portion of state government has a geographical component
      – natural resource management
      – highways and transportation
 • businesses use GIS for a very wide array of applications
      –   retail site selection & customer analysis
      –   logistics: vehicle tracking & routing
      –   natural resource exploration (petroleum, etc.)
      –   precision agriculture
      – civil engineering and construction
 • scientific research employs GIS
      – geography, geology, botany
      – anthropology, sociology, economics, political science
      – epidemiology
                                             ….the next slides illustrate more of these 7
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
           Where GIS is being Applied: I
      • Urban Planning,                        • Environmental Sciences
        Management & Policy                       – Monitoring environmental risk
            – Zoning, subdivision                 – Modeling stormwater runoff
              planning                            – Management of watersheds,
            – Land acquisition                      floodplains, wetlands, forests,
            – Economic development                  aquifers
            – Code enforcement                    – Environmental Impact Analysis
            – Housing renovation                  – Hazardous or toxic facility siting
              programs                            – Groundwater modeling and
            – Emergency response                    contamination tracking
            – Crime analysis
            – Tax assessment

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
           Where GIS is being Applied: II
 • Political Science                           • Education Administration
       – Redistricting                            – Attendance Area Maintenance
       – Analysis of election results             – Enrollment Projections
       – Predictive modeling                      – School Bus Routing
 • Civil Engineering/Utility                   • Real Estate
       – Locating underground facilities          – Neighborhood land prices
       – Designing alignment for                  – Traffic Impact Analysis
         freeways, transit                        – Determination of Highest and
       – Coordination of infrastructure             Best Use
         maintenance                           • Health Care
 •    Business                                    – Epidemiology
       – Demographic Analysis                     – Needs Analysis
       – Market Penetration/ Share                – Service Inventory
       – Site Selection

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
             Where Most UT-D Students Come From/Go To
                  the major areas of GIS application
  • Local Government
        – Public works/infrastructure management (roads, water, sewer)
        – Planning and environmental management
        – property records and appraisal
  • Real Estate and Marketing
        – Retail site selection, site evaluation
  • Public safety
        – Crime analysis, fire prevention, emergency management
  • Natural resource exploration/extraction
        – Petroleum, minerals, quarrying
  • Transportation
        – Airline route planning, transportation modeling
  • Public health and epidemiology
  • The Geospatial Industry
        – Data development, application development, programming
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                   What GIS Applications Do:
                    manage, analyze, communicate
       • make possible the automation of activities involving geographic data
             –   map production
             –   calculation of areas, distances, route lengths
             –   measurement of slope, aspect, viewshed
             –   logistics: route planning, vehicle tracking, traffic management
       • allow for the integration of data hitherto confined to independent domains
         (e.g property maps and air photos).
       • by tieing data to maps, permits the succinct communication of complex
         spatial patterns (e.g environmental sensitivity).
       • provides answers to spatial queries (how many elderly in Richardson live
         further than 10 minutes at rush hour from ambulance service?)
       • perform complex spatial modelling (what if scenarios for transportation
         planning, disaster planning, resource management, utility design)

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
            Defining Geographic Information Systems
        • The common ground between information processing and
          the many fields using spatial analysis techniques.
          (Tomlinson, 1972)
        • A powerful set of tools for collecting, storing, retrieving,
          transforming, and displaying spatial data from the real
          world. (Burroughs, 1986)
        • A computerised database management system for the
          capture, storage, retrieval, analysis and display of spatial
          (locationally defined) data. (NCGIA, 1987)
        • A decision support system involving the integration of
          spatially referenced data in a problem solving
          environment. (Cowen, 1988)

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
          An Inelegant Definition for GISy
   A system of integrated computer-based tools for end-to-
     end processing (capture, storage, retrieval, analysis,
     display) of data using location on the earth’s surface
     for interrelation in support of operations management
     and decision making.
               • set of integrated tools for spatial analysis
               • encompasses end-to-end processing of data
                     – capture, storage, retrieval, analysis/modification, display
               • uses explicit location on earth’s surface to relate data
               • aimed at decision support, as well as on-going operations

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
       How GIS differs from Related Systems
   • DBMS--typical MIS data base contains implicit but not explicit locational information
        – city, county, zip code, etc. but no geographical coordinates
        – is 100 N. High around the corner or across town from 200 E Main?
   •   automated mapping (AM) --primarily two-dimensional display devices
        – thematic mapping (choropleth,etc such as SAS/GRAPH, DIDS, business mapping
           software) unable to relate different geographical layers (e.g zip codes and counties)
        – automated cartography--graphical design oriented; limited database ability
   •   facility management (FM) systems--
        – lack spatial analysis tools
   • CAD/CAM (computer aided design/drafting)--primarily 3-D graphic
       creation (engineering design) & display systems
        – don’t reference via geographic location
        – limited (if any) database ability (especially for non-spatial data)
   •   scientific visualization systems--sophisticated multi-dimensional graphics, but:
        – lack database support
        – lack two-dimensional spatial analysis tools

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                    Knowledge Base for GIS
        graphics                                                   Application Area:
                                                                   public admin.
        database                               GIS                 planning
        system administration
                                                                   mineral exploration
                                                                   site selection
                         Geography                                 marketing
                         and related:                              civil engineering
                         cartography                               criminal justice
                         spatial statistics.
                                                     ….next slides show details
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                                  Contributors to GIS: I
            The convergence of technological fields and traditional disciplines

    • Geography                                  • Remote Sensing
          – Broadly concerned with                  – images from air and space are a
            understanding the world and               major (& growing) source of spatial
            man's place in it                         data
          – long tradition in spatial analysis      – low cost and consistent update of
          – provides techniques for                   input data anywhere in the world
            conducting spatial analysis             – remote sensing software contains
    • Cartography                                     sophisticated analytical functions
          – concerned with the display of           – interpreted data from remote
            spatial information                       sensing can be merged with other
                                                      GIS data
          – maps have been a major source of
            information input for GIS            • Photogrammetry
          – long tradition in map design            – uses aerial photographs for making
            which is an important output              accurate spatial measurements
            from GIS                                – source of most data on topography
                                                      (elevation) used in GIS

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                               Contributors to GIS: II
      The convergence of technological fields and traditional disciplines
  • Surveying                                  • Statistics
        – provides high quality data on            – many GIS models are statistical
          positions of land boundaries,            – many statistical techniques used in
          buildings, etc.                            GIS analysis
                                                   – statistics important to understanding
  •    Geodesy                                       issues of error and uncertainty in
        – Source of high accuracy                    GIS data
          positional control for GIS      • Operations Research
        – GPS (global positioning system)    – optimizing techniques used in many
          technology is revolutionizing        GIS applications such as routing
          efficiency, cost, and accuracy  • Computer Science
                                                   – earlier computer-aided design
                                                     (CAD) work in CS
                                                   – computer graphics and visualization
                                                   – database management systems
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                 The Purpose of a GISystem
       • allows the geographic features in real
         world locations to be digitally represented
         so that they can be abstractly presented in
         map (analog) form, and can also be worked
         with and manipulated to address some
       • provides a digital representation of the real
         world for use in operational management,
         decision making, and science
                                               (see associated diagrams)
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                          The GIS Data Model:
           Geographic Integration of Information
                                               Administrative Boundaries

                                                 Digital Orthophoto

    • Data is organized by layers, coverages or themes (synonomous
    concepts), with each theme representing a common feature.
    • Layers are integrated using explicit location on the earth’s
    surface, thus geographical location is the organizing principal.
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                    The GIS Model: example
                                                  Here we have three layers or themes:
                         roads                     --roads,
                  longitude                        --hydrology (water),
                                                   --topography (land elevation)
                                                  They can be related because precise
                                                  geographic coordinates are recorded
                  hydrology                       for each theme.
              longitude                        Layers may be represented in two ways:
                                               •in vector format as lines
                                               •in raster(image) format as pixels

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
        GIS System Architecture and Components

                                               Data Input

             Query Input

                      Output: Display                Transformation
                      and Reporting                   and Analysis

7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                                     Course Content
   Part I: Overview
   • What is GIS                               Part III: Practice
   • Fundamental GIS Concepts                  • Data Input:
     and Primary Software                        preparation and
   • Hands-on Intro to ArcGIS                    integration
         – (lab sessions @ 4:00-7:00pm         • Data analysis and
           or 7:00-10:00pm)                      modeling
   Part II: Principles                         • Data output and
   • Terrestrial data structures                 application examples
         – representing the real world
   • GIS Data Structures                       Part IV: The Future
         – representing the world in a         • Future of GIS
   • Data Quality
         – An essential ingredient
7/18/2011 Ron Briggs, UTDallas, Intro to GIS
                                    Hands-on Projects
     • Locating a Day-care
           – intro to GIS capabilities
           – illustration of a major application: site selection
     • Texas Demographic growth
           – manipulation of data and mapping principles
           – another major application: analysis of spatial patterns
     • Geocoding Housing Sales
           – techniques and data requirements for geocoding
           – another application: geocoding/address matching
     • Creating a Census Tract layer or a Geological Map
           – editing and creating topologically consistent data
           – how new data layers can be created
     • Pipeline Routing
           – data selection, buffering and spatial analysis
           – another major application: corridor studies
7/18/2011 Ron Briggs, UTDallas, Intro to GIS