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Transcript of How to Pick a GIS - West Virginia Universitypages.geo.wvu.edu/~elmes/Geog350/Selecting GIS1.pdf ·...
How to Pick a GISGIS SoftwareGIS Software
Chapter 8 in Longley, Chapter 8 in Longley, GoodchildGoodchild, , Maguire, and Maguire, and RhindRhind, 2001, 2001
How to Pick a GIS
Evolution of GIS softwareEvolution of GIS softwareArchitecture of GIS softwareArchitecture of GIS softwareTypes of softwareTypes of softwareExample productsExample productsThe GIS marketThe GIS market
A functional definition of GIS
A GIS is often defined not for what it is but A GIS is often defined not for what it is but for what it can do.for what it can do.If the GIS does not match the requirements If the GIS does not match the requirements for a problem, no GIS solution will be for a problem, no GIS solution will be forthcoming.forthcoming.A GIS may have overcapacity.A GIS may have overcapacity.
Ken Dueker’s definition of GIS (Reprise)
““ A special case of information systems A special case of information systems where the database consists of observations where the database consists of observations on spatially distributed features, activities or on spatially distributed features, activities or events, which are definable in space as events, which are definable in space as points, lines or areas. A GIS manipulates points, lines or areas. A GIS manipulates data about these points, lines and areas to data about these points, lines and areas to retrieve data for ad hoc queries and retrieve data for ad hoc queries and analyses.”analyses.”
GIS Software
The geoprocessing engines of GISThe geoprocessing engines of GISMajor functionsMajor functions
Collect, store, mange, query, analyze and presentCollect, store, mange, query, analyze and present
Key termsKey termsProgramProgram –– collections of instructions to manipulate datacollections of instructions to manipulate dataPackagePackage –– integrated collection of programsintegrated collection of programsComponentComponent –– selfself--contained, reusable software building contained, reusable software building blocksblocks
Evolution of GIS SoftwareSubSub--routine libraries (60s/70s)routine libraries (60s/70s)
Libraries of small programs (subLibraries of small programs (sub--routines)routines)Required advanced programming skillsRequired advanced programming skills
Tool box with CLI (70s/80s)Tool box with CLI (70s/80s)Basic package with Command Line InterfaceBasic package with Command Line InterfaceRequired advanced technical skillsRequired advanced technical skills
TaskTask--oriented system (90s/00s)oriented system (90s/00s)Graphical User Interface (GUI)Graphical User Interface (GUI)Customization capabilities to create specificCustomization capabilities to create specific--purpose purpose applicationsapplications
Project and Departmental GISProject GIS
Department GIS
Enterprise GIS
Three-tier Architecture
User InterfaceUser Interface
Data ManagementData Management
ToolsTools
Data
Presentation
Business Logic
Data Server
The “critical six”“critical six” functional capabilities extracted from Deuker’sdefinition:
Data captureData captureStorageStorageManagementManagementRetrievalRetrievalAnalysisAnalysisDisplayDisplay
Data capture functions
DigitizingDigitizingScanningScanningMosaicingMosaicing (edge matching)(edge matching)EditingEditingGeneralizationGeneralizationTopological cleaningTopological cleaning
Steps in Mosaicing
Line generalization
Storage Functions
CompressionCompressionMetadata handlingMetadata handlingControl via macros or languagesControl via macros or languages
CustomizationCustomization
Format supportFormat supportMaintenance Maintenance UpdateUpdate
Compression
By data structureBy data structurequad treesquad treesrun length encodingrun length encoding
By data formatBy data formatcompressed TIFcompressed TIFjpegjpeg
By physical compressionBy physical compressiondigit handlingdigit handling
Data Management Functions
Physical model supportPhysical model supportDBMSDBMS
QueryQuery
Address matchingAddress matchingMaskingMaskingCookie cuttingCookie cutting
Clip to study areaClip to study area
Cookie cutting
Data Retrieval and Analysis Functions
Locating entities / finding recordsLocating entities / finding recordsSelecting by attributesSelecting by attributesSelecting by LocationSelecting by Location
BufferingBufferingMap overlayMap overlayMap algebraMap algebra
Map Algebra
Data Analysis Functions
BufferingBufferingMap overlayMap overlayMap algebraMap algebraInterpolation Interpolation -- creating surfacescreating surfacesOptimal path selectionOptimal path selectionGeometric tests Geometric tests -- spatial relationshipsspatial relationshipsSlope calculationSlope calculation
Interpolation
?
Data Display Functions
Desktop mappingDesktop mappingInteractive modification of cartographic Interactive modification of cartographic elementselementsGraphic file exportGraphic file export
Functional Capabilities are By-products of Data StructureRaster systems work best in forestry, Raster systems work best in forestry, photogrammetryphotogrammetry, remote sensing, terrain , remote sensing, terrain analysis, and hydrology.analysis, and hydrology.Vector systems work best for land parcels, Vector systems work best for land parcels, census data, precise positional data (GPS, census data, precise positional data (GPS, fieldwork), and networks.fieldwork), and networks.
Vector
Precision intactPrecision intactUsed when individual coordinates are Used when individual coordinates are importantimportantMore concise spatial descriptionMore concise spatial descriptionAssumes feature model of landscapeAssumes feature model of landscapeEasy to transform data e.g. map projectionsEasy to transform data e.g. map projections
RasterBetter for field dataBetter for field dataUsed by most imaging systemsUsed by most imaging systemsCan be compressedCan be compressedEasy to display and analyzeEasy to display and analyzeMany common formatsMany common formatsHowever, most systems now use bothHowever, most systems now use bothRaster layer often backdropRaster layer often backdrop--onscreen onscreen editingediting
The “Big Eight”
Form the bulk of operational GIS in Form the bulk of operational GIS in professional and educational environmentsprofessional and educational environmentsThere are some significant differences There are some significant differences between these “big eight” systems.between these “big eight” systems.
Professional GISFull featuredFull featured
AutomationAutomationManipulationManipulationData accessData accessQueryQuerySpatial Analysis
VisualizationVisualizationMappingMappingAdvanced editingAdvanced editingCustomizationCustomization$10,000$10,000
Spatial Analysis
Arc/Info
ESRIRedlands, CAArc/InfoMarket leaderworkstation (mostly)remarkable functionalitymany formats supportedArcEditArcGRIDArcPlotINFO
ArcInfo 8
Desktop GIS
Data exploitationData exploitationData accessData accessQueryQuerySpatial AnalysisSpatial AnalysisSimple editing
VisualizationVisualizationMappingMappingCustomizationCustomization$1500$1500
Simple editing
ArcView
Versions 1-3, 3.1PC WindowsAvenueWeb linksMap ObjectsExtensions
MapInfoBased in Troy, NYMapping functionsLimited GIS functionalityUses Visual BasicMany applicationsFavored for 911, field
MapInfo
AutoCAD MAP
Windows all versionsSQL DBF AccessExtension to AutoCADMenu-basedMassive installed baseAdded grid, projection & topology supportDB links good.3D links good
GRASS
First UNIX GISDeveloped by ArmyCorps of EngineersUNIX functionalityMany unique functionsFree until recentlyMany data setsBaylor University now supports
IDRISI
Developed at ClarkUniversity, Worcester MAOriginal in PASCAL, withopen codeDevelopment uses a specialtyWindows/DOSSpatial analysis/stats extensions
Maptitude
Caliper CorporationConsultancyTRANSCAD and GIS+Many network solutionsWindowsImport/ExportAddress matching
Microstation MGE
CAD software with GISextensionsIntergraph Corp, Huntsville ALUses Windows NTMany parcel applicationsWeb extensions, server tools etc.
Hand-held
FieldField--based GISbased GISLightweight hardwareLightweight hardwareExtension of desktopExtension of desktopLimited capabilitiesLimited capabilitiesData collectionData collectionMobile mappingMobile mapping$500$500
Autodesk OnSite & ArcPad
Component GIS
Do it yourself GISDo it yourself GISSoftware building blocksSoftware building blocksEmbeddableEmbeddableHighly customizableHighly customizableHighly interoperableHighly interoperableLightweight, low cost deploymentsLightweight, low cost deployments$5000 for 50 ($100 each)$5000 for 50 ($100 each)
Internet GIS
Distributed GISDistributed GISCentralized serviceCentralized serviceSimple, low costSimple, low costEasy to useEasy to useMap focused, some other servicesMap focused, some other servicesReadRead--onlyonly$7500 per server (10$7500 per server (10--30 users)30 users)
MapGuide
GIS Viewers
Free GISFree GISLightweightLightweightLow costLow costRead onlyRead onlyMiniMini--desktop GISdesktop GISNo customizationNo customization$0!$0!
A variety of issues should be considered in system selection:
costcostupgradesupgradesLAN configuration supportLAN configuration supporttraining needstraining needsease of installationease of installationmaintenancemaintenancedocumentation and manualsdocumentation and manualshelphelp--line and vendor supportline and vendor supportmeans of making patchesmeans of making patches
workforceworkforce
GIS Market
0 1000000 2000000 3000000
Users
Internet
Viewer
Component
Hand-held
Desktop
Professional
Type of Software System
Summary
GIS software is developing fastGIS software is developing fastConsistent GIS architectureConsistent GIS architectureMajor development areasMajor development areas
InternetInternetHandHand--heldheld
Increasingly standardsIncreasingly standards--basedbasedVery wide rangingVery wide rangingRationalization of vendorsRationalization of vendors
GIS Case Study
GIS IN ACTION
September 11, 2001September 11, 2001The World Trade Center The World Trade Center
Towers, NYCTowers, NYC
GIS World Trade Center operations at Pier 92
GIS support for firefighters, rescue workers, GIS support for firefighters, rescue workers, utility crews utility crews 24 hours a day / 7 days a week support for 2+ 24 hours a day / 7 days a week support for 2+ monthsmonths50+ GIS professionals50+ GIS professionals
DataNYCMapNYCMap
OrthophotographyOrthophotographyPlanimetricPlanimetric mapsmaps
Thermal imageryThermal imageryLIDAR imageryLIDAR imageryGPS dataGPS data
NYCMap30 cm resolution orthophotography
Planimetric map -absolute spatial accuracy of half a meter
LIDAR
Thermal imaging
Thermal remote sensing data collected at the WTC on September 16. Source: Roger Clark, USGS, Open File report 01-0429
GPS
Problems
Maintaining building status databaseMaintaining building status databaseUnique identifiers for the buildings?Unique identifiers for the buildings?Data consistencyData consistencyData integrityData integrityTIME!TIME!
Lessons learned
NYC GIS infrastructure was criticalNYC GIS infrastructure was criticalCities should connect their spatial data to its Cities should connect their spatial data to its attributes!attributes!Need for cartographic standardsNeed for cartographic standardsNeed mobile access to GISNeed mobile access to GISVersion management for multiVersion management for multi--user user environmentenvironment