2. introduction to gis (geographical information system)
Post on 08-Apr-2018
234 Views
Preview:
TRANSCRIPT
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 1/20
Introduction to GISIntroduction to GIS(Geographical Information(Geographical Information
System)System)
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 2/20
What Is a GIS?What Is a GIS?
A geographic information system (GIS) isA geographic information system (GIS) isa computera computer--based tool for mapping andbased tool for mapping andanalyzing things that exist and events thatanalyzing things that exist and events that
happen on earth.happen on earth. GIS technology integrates commonGIS technology integrates common
database operations such as query anddatabase operations such as query andstatistical analysis with the uniquestatistical analysis with the uniquevisualization and geographic analysisvisualization and geographic analysisbenefits offered by maps.benefits offered by maps.
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 3/20
GIS DefinitionGIS Definition
Burrough (1986) defines GIS asBurrough (1986) defines GIS as ³a set of tools for ³a set of tools for collecting, storing, retrieving at will, transformingcollecting, storing, retrieving at will, transformingand displaying spatial data from the real world and displaying spatial data from the real world for a particular set of purposes´ for a particular set of purposes´
Aronoff (1989) gives a. general description of GISAronoff (1989) gives a. general description of GISasas ³any manual or computer ³any manual or computer--based set of based set of procedures used to store and manipulate procedures used to store and manipulategeographically geographically--referenced data.´ referenced data.´
More specifically, Aronoff (1989) defines GIS asMore specifically, Aronoff (1989) defines GIS as aacomputer computer--based system that provides four sets of based system that provides four sets of capabilities to handle georeferenced Data: 1.capabilities to handle georeferenced Data: 1.Data input 2.Data management (Data StorageData input 2.Data management (Data Storageand Retrieval), 3. Manipulation and analysis, 4.and Retrieval), 3. Manipulation and analysis, 4.Data Output Data Output
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 4/20
The major challenges we face inthe world today--overpopulation, pollution,deforestation, natural disasters--have a critical geographicdimension.
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 5/20
Gis ConceptGis Concept
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 6/20
Evolution of GISEvolution of GIS
Revolution in information technology Revolution in information technology
Computer TechnologyComputer Technology
Remote SensingRemote Sensing
Global Positioning System (GPS)Global Positioning System (GPS)
Communication TechnologyCommunication Technology
Rapidly declining cost of computer Rapidly declining cost of computer
hardwarehardware
Enhanced Functionality of softwareEnhanced Functionality of software
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 7/20
Why GIS?Why GIS?
70% of the information includes some70% of the information includes somegeographical Facts in the decisiongeographical Facts in the decision--making processmaking process
Ability to assimilate divergent sources of Ability to assimilate divergent sources of data both spatial and nondata both spatial and non--spatialspatial(attribute data)(attribute data)
Visualization impactVisualization impact
Sharing of informationSharing of information
Analytical capability in a spatial contextAnalytical capability in a spatial context
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 8/20
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 9/20
Spatial OperationsSpatial Operations
Many computer programs can handleM
any computer programs can handlegeographic data such as those describedgeographic data such as those describedbelowbelow
1.1.Spreadsheets (e.g., lotus 1Spreadsheets (e.g., lotus 1 --22--3,3,QuatroPro).QuatroPro).
2.2.Database Management SystemsDatabase Management Systems(e.g., Oracle, dBase)(e.g., Oracle, dBase)
3.3.Computer Aided Design (e.g.,Computer Aided Design (e.g.,AutoCad)AutoCad)
4.4.Cartographic packages (e.g. AldusCartographic packages (e.g. AldusFreehand, CarthoGraphix)Freehand, CarthoGraphix)
5.5.Photogrammetrical software (e.g.Photogrammetrical software (e.g.DMS)DMS)
6.6.Image Processing Software (e.g.,Image Processing Software (e.g.,
ERDAS)ERDAS)
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 10/20
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 11/20
Geometry and attributes of Spatialobjects
Points, Its ID and Attributes
Lines, Its IDs and AttributesPolygons, Its IDs and Attibutes
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 12/20
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 13/20
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 14/20
Perform Geographic QueriesPerform Geographic Queriesand Analysisand Analysis
Improve OrganizationalImprove OrganizationalIntegrationIntegration
Make Better DecisionsMake Better Decisions
Making
Maps
Making
Maps
What Can GIS Do for You?What Can GIS Do for You?
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 15/20
Component of GISComponent of GIS
HardwareHardwareSoftwareSoftware
DatabaseDatabase
People (Users)People (Users)
Methods (Policy and ProceduresMethods (Policy and Procedures
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 16/20
How GIS Works ?How GIS Works ?
1.1. Geographic ReferencesGeographic References
2.2. Vector and Raster ModelsVector and Raster Models
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 17/20
GIS TasksGIS Tasks
InputInput
ManipulationManipulation
ManagementManagementQuery and AnalysisQuery and Analysis
VisualizationVisualization
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 18/20
Proximity AnalysisProximity Analysis
Overlay AnalysisOverlay Analysis
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 19/20
Data for GISData for GIS
What Map Data Do I Need?What Map Data Do I Need?
±±Base MapsBase Maps
±±
BusinessM
aps and DataBusinessM
aps and Data±±EnvironmentalMaps and DataEnvironmentalMaps and Data
±±General Reference MapsGeneral Reference Maps
8/7/2019 2. Introduction to GIS (Geographical Information System)
http://slidepdf.com/reader/full/2-introduction-to-gis-geographical-information-system 20/20
How Do I Get Map Data?How Do I Get Map Data?
Methods In NepalMethods In Nepal
±± Existing mapsExisting maps
±±
Field SurveyField Survey±± Digital data available inDigital data available in
Departments of Survey, MinDepartments of Survey, MinBhawan, Kathmandu, NepalBhawan, Kathmandu, Nepal
±±ICIMODICIMOD
top related