m.sc report on application of gis softwares

8/7/2019 M.SC Report on Application of GIS Softwares

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Application of GIS Software

Submitted as partial completion of M.SC Degree in Geography

2009PRESIDENCY COLLEGE, KOLKATADIKSHA BOSE


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What is GIS?

Definition

Geographic Information System (GIS) is a computer based integrated technology, wheregeographic data along with its attributes from various sources are collected into a system for storage, retrieval, manipulation and presenting the same. There are many definitions of GIS witheach definition reflecting an individual perception of GIS and the type of problem statement.

Elements There are four major elements which a basic GIS system needs. They are Hardware, Software,Data (Dataware) and Methods, Persons (Brainware), which are depicted in the Fig below:

The Different Components of a GIS

Functions of a GIS

Data Input/Output GIS accepts data from different sources in different forms. Some of the main sources of GIS dataare digital / analog maps, aerial photographs, satellite imageries and field survey. Once the data isstored it can be manipulated and analyzed to reach a particular conclusion.

Data Management Data management is a process in which the stored data is maintained systematically and allowsproper retrieval of data.

Analysis Analysis is an important function of GIS, which answers the queries, based the geographicalfeature, their location with respect to other features in association with attribute data.


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Digitized State Map of India (Spatial Data) with Statistical Information attached for eachState (Attribute Data)

Benefits of GISUse

GIS can be applied to various disciplines like watershed management, network analysis of roadsand waterways, public health care monitoring, vehicle routing and many more. Analysis of spatialand non-spatial data becomes easy and supports querying, overlay and buffer analysis. One cancombine data in new ways to analyze patterns and trends not evident in separate databases. Suchan analysis can lead to predictive tools for hazards management, better decision support system

and optimizing sales and services for different sectors. Thus the use of GIS technologies helpsempower people to make better decisions by increasing access to different dataset in its spatialcontext.

Some of the Basic Functions performed in MapInfo along with their procedures:

The various tasks that have been done are as follows:

1. Selecting a Raster File & opening it in MapInfo2. Displaying & then Registering the raster file or straightaway registering the raster file by

assigning co-ordinate values (longitude/latitude) to four points in the image, using theConverter Tool to change longitude/latitude values from DMS (degree-minute-second)format to decimal format, if necessary.

3. Using the Cursor Location option to extract longitude & latitude for various places / pointfeatures / locations in the registered (geo-referenced) map & again using the Converter tool to change the decimal values into DMS format, if so required.

4. Using the Ruler tool to measure distances (straight-line as well as along roads or of streams). Before that, changing the display units to the desired type (miles / kilometers /metres) from the Map Options menu.

5. Creating new layers atop the registered map layer & digitizing the various featurespresent in the map, one layer for each discrete feature.

6. Modifying the Attribute Data Table Structure for various map objects to add / remove /

rename / change variable type for any of the map object layers7. Adding Attribute Data to the vectorized (spatial) map objects using the Info tool.


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8. Displaying the various digitized objects as part of point / line / polygon feature layers.Discerning map features individually and overlaying two or more layers to obtain:

a. Communication Layer (roads (all-types), railways, telegraph-lines) Linear features;

b. Settlement Layer & Important Buildings Layer (hospital, post-office, railway-station, etc.) Point features & Polygon features

c. Vegetation Layer (forests) Polygon featured. Drainage Layer (streams, canals, ponds) Line & Polygon featurese. Land-use & Land-cover Layer showing all of the above features together f. Contour lines & resultant DEM

9. From a map of HOOGHLY, the various blocks have been digitized as polygons &various attribute data input & attached to the map objects. Using the above generatedgeo-database, a number of thematic maps have been generated.

10. Final layout / presentation for each layer / thematic map complete with scale, north arrow& suitable labeling.


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DIFFERENT PROCESSES EMPLOYED WITH THE HELP OF MAP INFO TOVECTORIZE A RASTER IMAGE

OPENING THE RASTER FILE (part of a scanned toposheet) in MapInfo

REGISTERING THE RASTER MAP


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CONVERTING MEASUREMENT UNITS & FINDING DISTANCES USING RULER TOOL

CREATING A NEW TABLE & OVERLAYING IT ON RASTER FOR FEATUREDIGITIZATION PURPOSE


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SOME DIGITIZED POINT FEATURES

DIGITIZED LINEAR FEATURES: DIFFERENT KINDS OF ROADS


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DIGITIZED POLYGON FEATURES: FOREST AREA AND SETTLEMENT


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EXTRACTION OF LATITUDE AND LONGITUDE FOR DIGITISED REGIONS

UPDATING COLUMN

EXTRACTING LONGITUDE


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EXTRACTING LATITUDE

EXTRACTING LENGTH OF ROADS


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DIGITISING AN ADMINISTRATIVE MAP FOR THE PURPOSE OFGENERATING THEMATIC MAPS

REGISTERING OF BLOCK MAP OF HOOGHLY DISTRICT (RASTER LAYER)

DIGITIZATION OF VARIOUS DISTRICTS AS INDIVIDUAL POLYGONS


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VECTORIZED LAYER WITH ATTRIBUTE DATA INPUT FOR EACHDISTRICT USING INFO TOOL (E.g. Singur)

USING SQL SELECT TO LINK EXTERNAL DATA TABLE WITH MAPOBJECT ATTRIBUTE TABLE


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ATTRIBUTE DATA TABLE FOR ALL DISTRICTS

LINKED MAP OBJECT WITH RESPECTIVE ATTRIBUTE DATA (e.g.Arambag)


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GENERATION OF CHOROPLETH MAPS

THE CREATE THEMATIC MAP MENU TO GENERATE DIFFERENTKINDS OF THEMATIC MAPS BASED ON DIFFERENT ATTRIBUTEVARIABLES INPUT (e.g. CHOROPLETH MAP USING RANGE THEMATICTYPE)

CHOOSING THE VARIABLE (TOTAL POPULATION: TOT_P 2001) FOR CHOROPLETH MAP


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FIXING THE RANGES

LEGEND CREATION


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GENERATION OF BARS GRAPHS

THE BAR CHART CREATION OPTION IN THE CREATE THEMATIC MAP MENU

CHOOSING OF VARIABLES FOR GENERATION OF BAR CHARTS


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GENERATION OF PIE CHARTS

PIE CHART GENERATION MENU

CHOOSING THE VARIABLES FOR THE PIE CHART


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PIE CHART STYLES & SCALE DETERMINATION MENU


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SOME MORE EXAMPLES OFTHEMATIC MAP GENERATION


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m.sc report on application of gis softwares

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