gis introduction

OVERVIEW & OVERVIEW & INTRODUCTION to GISINTRODUCTION to GIS

OVERVIEW & OVERVIEW & INTRODUCTION to GISINTRODUCTION to GIS

Ajaze Parvez KhanAjaze Parvez Khan

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• London cholera epidemic London cholera epidemic 18541854

Cholera deathCholera death

Water pumpWater pump

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GIS concepts are not new!GIS concepts are not new!GIS concepts are not new!GIS concepts are not new!

This technology has This technology has developed from:developed from:– Digital cartography and CADDigital cartography and CAD– Data Base Management SystemsData Base Management Systems

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ATTRIBID X,Y1

2

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ID1

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CAD SystemCAD System Data Base Management SystemData Base Management System

GIS: historical backgroundGIS: historical backgroundGIS: historical backgroundGIS: historical background

GIS: a formal definitionGIS: a formal definition

“A system for capturing, storing, checking, integrating, manipulating, analysing and displaying data which are spatially referenced to the Earth. This is normally considered to involve a spatially referenced computer database and appropriate applications software”

GIS is a System of computer software, hardware and data, and personnel to help manipulate, analyze and present information that is tied to a spatial location –

• spatial location – usually a geographic location• information – visualization of analysis of data • system – linking software, hardware, data• personnel – a thinking explorer who is key to the power of GIS

Geographic Information Geographic Information

SystemsSystems

A Definition of GISA Definition of GIS

Geographic Information Geographic Information

SystemsSystems

A Definition of GISA Definition of GIS

Hardware +Software +Data ware +Human-ware = GIS

What consists “GIS”What consists “GIS”What consists “GIS”What consists “GIS”

What consists “GIS”What consists “GIS”What consists “GIS”What consists “GIS”

What is What is Not Not GIS GIS ??What is What is Not Not GIS GIS ??

• GPS – Global Positioning System

• A static map – paper or digital– Maps are often a “product” of a GIS

– A way to visualize the analysis

• A software package

First Step In GIS : Data For First Step In GIS : Data For GIS ApplicationsGIS Applications

First Step In GIS : Data For First Step In GIS : Data For GIS ApplicationsGIS Applications

• Remote Sensing & Aerial Photography

• Surveying• GPS – Global Positioning

System– accurate locations

• Digitized and Scanned Maps– purchased, donated, free

(Internet)– created by user

• Data Bases – Tables of data

• Raster FormatRaster Format

• Vector FormatVector Formatpoint

1,6

2,5

5,4

4,1

7,105,9

4,7

6,68,6

9,8

line

polygon

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5 10

5

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as geometric objects:

points, lines, polygons

as image files

composed of grid-cells

(pixels)

Second Step In GIS Second Step In GIS Information/Geographic/Spatial data Information/Geographic/Spatial data

storagestorage

Second Step In GIS Second Step In GIS Information/Geographic/Spatial data Information/Geographic/Spatial data

storagestorage

RASTER - VECTOR Data ModelsRASTER - VECTOR Data ModelsRASTER - VECTOR Data ModelsRASTER - VECTOR Data Models

Geography-Spatial Geography-Spatial DataData

Geography-Spatial Geography-Spatial DataData

• Spatial data is data pertaining to the location and spatial dimensions of geographical entities

• Estimates are that 80% of all data has a spatial component– Data from most sciences can be

analyzed “spatially”

Place namePlace nameGrid co-ordinateGrid co-ordinate

PostcodePostcode

Distance & bearingDistance & bearingDescriptionDescription

Latitude / LongitudeLatitude / Longitude

Characteristics of spatial dataCharacteristics of spatial dataCharacteristics of spatial dataCharacteristics of spatial data

LocationLocation

• The shape of a The shape of a building or Citybuilding or City

• The course of a The course of a river, the route river, the route of a roadof a road

• The shape of The shape of the landscape, the landscape, reliefrelief

Characteristics of spatial dataCharacteristics of spatial dataCharacteristics of spatial dataCharacteristics of spatial data

GeometryGeometry

Connected toConnected to Within or NearWithin or Near Adjacent toAdjacent to

For e.g. DEALFor e.g. DEAL

Adarsh vihar or Saraswati viharAdarsh vihar or Saraswati vihar Raipur RoadRaipur Road Adjacent to Guru Nanak Academy SchoolAdjacent to Guru Nanak Academy School

Characteristics of spatial dataCharacteristics of spatial dataCharacteristics of spatial dataCharacteristics of spatial data

TopologyTopology

• Socio-economic dataSocio-economic data– Regional health dataRegional health data– Consumer / lifestyle profilesConsumer / lifestyle profiles

• Environmental dataEnvironmental data– Topographic dataTopographic data– Thematic data, soils, geologyThematic data, soils, geology

Spatial Data: examplesSpatial Data: examplesSpatial Data: examplesSpatial Data: examples

• Features

– Buildings– Road centrelines– Lamp columns– Road surfaces

Data Modelling - step 1Data Modelling - step 1

Point

Line

Polygon

Data Modelling - step 2Data Modelling - step 2

Feature : Building

Object: Polygon

Entity: Tourist

Information

Bureau

Data Modelling - step 3Data Modelling - step 3

Name : ROMA

Address: 5 Market Place

Town: Kingston

Owner: Ms X

Tel. No: 0181 547 1245

Floor space 1300 sq m

Attributes/ CharactersticsAttributes/ Characterstics

Database“Not Easy to Interpret”

Database“Not Easy to Interpret”

States

Five Data Layers “Alike” FeaturesFive Data Layers “Alike” Features

Roads

CapitalsRivers

Lakes

Visualization “A picture Worth a Thousand Words”

Visualization “A picture Worth a Thousand Words”

In the context of GIS, analysis is...“Deriving new information from existing data”

Some Techniques...

•Simple QuerySimple Query

•BufferingBuffering

•OverlaysOverlays

•Network AnalysisNetwork Analysis

•EtcEtc....

GIS - AnalysisGIS - Analysis

• The identification of objects and their attributes either by location or attribute query.

MapInfoMapInfo

Simple QuerySimple Query

• Creation of an area of interest around an object

Buffering/Proximity AnalysisBuffering/Proximity Analysis

Network AnalysisNetwork AnalysisNetwork AnalysisNetwork Analysis

Network analysis is used Network analysis is used for identifying the most for identifying the most efficient efficient routess or paths for or paths for allocation of services of services.

• Overlaying is superimposing two or more Overlaying is superimposing two or more map layers to produce a new map layer.map layers to produce a new map layer.

• Example:Example:• Roads on one layer(Line)Roads on one layer(Line)• Buildings on another layer(Point)Buildings on another layer(Point)• Parks on the third layer(Polygon)Parks on the third layer(Polygon)

OverlaysOverlays

1. ARCGIS

2. ILWIS

3. ERDAS IMAGINE

4. ERMAPPER

5. GEOMEDIA

6. GRASS (Open source)

7. JTMaps (India) &

8. Free software's (TNTMIPS/GRASS/ARCVIEW3.0

Proprietary S/W sProprietary S/W s

Open source S/WOpen source S/W

Free Software'sFree Software's

GIS SOFTWARESGIS SOFTWARES

Some Ways GIS is Some Ways GIS is UsedUsed

Some Ways GIS is Some Ways GIS is UsedUsed

• Emergency Services – Fire & Police • Environmental – Monitoring & Modeling

• Business – Site Location, Delivery Systems

• Industry – Transportation, Communication, Mining, Pipelines, Healthcare

• Government – Local, State, Federal, Military

• Education – Research, Teaching Tool, Administration

Wherever Spatial Data Analysis is Needed

3D Mine with Well Data3D Mine with Well Data3D Mine with Well Data3D Mine with Well Data

Environmental Monitoring Environmental Monitoring ofof

Toxic PlumeToxic Plume

Environmental Monitoring Environmental Monitoring ofof

Toxic PlumeToxic Plume

Oil Spill and Oil Spill and Contamination estimationContamination estimation

Oil Spill and Oil Spill and Contamination estimationContamination estimation

Modeling of Future TrendsModeling of Future Trends

Thank YouThank YouThank YouThank You