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WELCOME TO PARTICIPANTS TO THIS CLASS

WELCOME TO PARTICIPANTS TO THIS CLASS. GEOGRAPHIC INFORMATION SYSTEM ( GIS) by J. K. RATH Dy Surveyor General Faculty of Cartography, Digital Mapping & GIS. Topics to be covered:-. ( j ) TOPOLOGY ( k ) DATA MODEL ( l ) DATA STRUCTURE ( m ) QUERIES & SPATIAL ANALYSIS

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WELCOME TO PARTICIPANTS TO THIS CLASS

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  1. WELCOME TO PARTICIPANTS TO THIS CLASS

  2. GEOGRAPHIC INFORMATION SYSTEM ( GIS) by J. K. RATH Dy Surveyor General Faculty of Cartography, Digital Mapping & GIS

  3. Topics to be covered:- ( j ) TOPOLOGY ( k ) DATA MODEL ( l ) DATA STRUCTURE ( m ) QUERIES & SPATIAL ANALYSIS ( n ) APPLICATION OF GIS ( o ) TRENDS IN GIS ( p ) GIS SOFTWARES ( q ) INTERNET, DESKTOP & HANDHELD GIS ( a) INTRODUCTION ( b ) WHY GIS ? ( c) WHAT IS GIS ? ( d ) EVOLUTION OF GIS ( e ) QUESTION A GIS CAN ANSWER & GIS OBJECTIVES ( f ) COMPONENTS OF GIS / ELEMENTS OF GIS ( g ) GIS DATA ( h ) REPRESENTATION OF SPATIAL DATA ( i ) REPRESENTATION OF ATTRIBUTE DATA

  4. Why GIS? :- GEOGRAPHY IS A PART OF OUR EVERYDAY LIFE; ALMOST EVERY DECISION WE MAKE IS CONSTRAINED, INFLUENCED OR DICTATED BY SOME FACTOR OF GEOGRAPHY Example:- --Fire engines are to be deployed on shortest / fastest routes. --Population in a State decides number of M.Ps. --Terrain elevation and slope influence Land slides. --Earthquake occurs due to Geological reasons.

  5. FACTOR INFLUENCING EVOLUTION OF GIS (i) Retrieval and analysis of map data by visual inspection is very difficult when large volume of data are involved. • Developments in the field of Computer and information technology have provided quantitative improvement in the speed of analysis of large volume of data sets. Also greater ease of user interaction, using standard windowing environment • Reduction in the price of GIS H/W and S/W. • Wider availability of GIS through the Internet as well as organization-wide local area networks Therefore many organizations now spend large amount of money on development GIS applications. .

  6. What is GIS? :- “ An organized collection of Computer h/w, s/w, geographical data and personnel designed to efficiently capture store, update, manipulate, analyze and display all forms of geographically referenced information”. E.S.R.I – 1990 ( Environmental System Research institute) In other words “A computer system capable of holding and using data describing places on the earth’s surface”. A GIS represents the real world consisting of many Geographic in terms of the related Data layers. Hydrology Real World Topography Landuse Soils Geology

  7. Evolution of GIS • CONCEPT OF STORING THE MAPS IN COMUTER BY GEOGRAPHERS IN 1962. • PERSONAL COMPUTERS - COMPUTER CARTOGRAPHY IN 1970. • FALLING PRICES - REACH TO COMMON PEOPLE - UTILITY MANAGEMENTS • SATELLITES - REMOTE SENSING SATELLITES - INCREASE IN GIS CAPABILITIES -1980 • LAUNCHING OF GPS SATELLITES - ACCURACY IMPROVEMENT - MORE UTILITIES.

  8. (c ) GIS objectives and Question a GIS can answer :- (i) GIS Objectives :- --Maximize the efficiency of planning and decision making . --Provide efficient means for data distribution and handling . --Elimination of redundant database –minimize duplication . --Capacity to integrate information from many sources . --Complex analysis / query involving geographical referenced data to generate new information .

  9. (ii) Question a GIS can Answer :- 1.The Object: what is it ? What exists at a particular location? 2.Condition : where is it ? Opposite of the first question, to find the location (x,y) of a place where a condition is satisfied . For example – where is IISM ? - Find all waste lands within 100m of the highway . - Find all sewer lines connecting to Musi river.

  10. (ii) Question a GIS can Answer :-contd…. 3. Trends:- What has changed since ----? (temporal changes) For example:- Find all states which reported population increase of > 20% between 1981-91 4. Patterns:- What spatial pattern exists ? This is concerned with the pattern of spatial distribution of data. Example:- (i) Take the statistics of number of accidents occurred during the last couple of years. All the locations with attributes are entered into a GIS. Now this data can be studied to find out whether there is any spatial pattern to the accidents. Do accident of a certain type occur only on specific location. (ii) Similarly, theft, robbery, terrorist activities of an area can also be analysed, predicted, from history (type of residents, record etc ) thro’ GIS for deployment of more vigilance.

  11. 5. Modeling :- For example : - If a new road is added to a network , what happens to the network parameters such capacity, load , traffic etc. - What happens if a toxic substance seeps into the local groundwater supply? - What happens if a volcanic lava enters a city’s sewer lines - Which part of the city will be affected ? - How to block it ?

  12. (d) Components of GIS / Elements of GIS 1.Hardware 2.Software 3.Data 4.Liveware Computer platform Data input & Spatial data Trained people Input devices verification Attribute data Scanners, Digitizers Data storage & CD database management Output devices Data output & presentation Plotters Data Transformation Printers Data manipulation/ Analysis Data Modeling

  13. An integration of five basic components Procedures A

  14. GEOGRAPHIC DATA Spatial dataAspatial data Map Features Attribute data Point, Line and Area Values / characteristics Qualitative Quantitative Raster Vector ANALYSIS

  15. Spatial Data:- Spatial data is that which has physical dimensions and geographic locations on the surface of the earth. For example : Roads, Buildings, Tanks Non-Spatial Data:- It refers to the descriptive information about the feature. For example: Name, Type, Length of a road.

  16. Sources of positional data Field survey Photogrammetry Remote Sensing Digitization of cartographic documents

  17. Sources of Attribute data • Field inspection • Photo interpretation • Other information sources (census, statistical bureau, NIC etc ) • Environmental monitoring

  18. REPRESENTATION OF SPATIAL INFORMATION VECTOR DATA MODEL

  19. DIGITAL REPRESENTATION OF A POINT 15 10 6, 7 5 5 10 15

  20. DIGITAL REPRESENTATION OF A LINE 15 X Y 2 4 4 5 5 7 8 10 14 12 10 5 5 10 15

  21. DIGITAL REPRESENTATION OF AN AREA X Y 2 4 4 5 5 7 8 10 14 12 10 2 2 4 15 10 5 5 10 15

  22. RASTER DATA ( Scanned map )

  23. Village-id Name Population Crop 101 Peddapalli 2000 Rice 102 Gopalpur 1500 Wheat 103 Gamapet 3500 Rice REPRESENTATION OF NON-SPATIAL INFORMATION Attribute data are stored as a set of numbers or characters in the form of a table

  24. BUILDING TOPOLOGY • TOPOLOGY REFERS TO THE UNDERLYING SPATIAL RELATIONSHIP. • IT EXPLICITLY PROVIDES THE LOGIC, THAT CONNECTS POINTS, LINES AND POLYGONS TO ONE ANOTHER. • IT DEFINES THE POSITIONAL RELATIONSHIPS • IT ALLOWS TO PERFORM SPATIAL RELATIONSHIP FUNCTIONS LIKE OVERLAYING, BUFFERING AND PROXIMITY FUNCTION. • IT DEFINES CONNECTIVITY - CONTIGUITY – CONTAINMENT (AREA DEFINITION) OF FEATURES

  25. DATA MODELS • Data Models are used for computer representation of spatial information • This is used to convert Real world Data into discrete objects. DATA MODELS Raster Vector Network Tin

  26. RASTER Vs VECTOR • RASTER VECTOR • Simple Data Structure * Complex Data Structure • Can combine RS Data * Can’t combine • Spatial Analysis is easy * Difficult • Economical * Costly • Larger Data volumes * Less Data volumes • Loss of information * No Loss • Better Visual Perception * Poor Visual Perception • Network Link Difficult * Easy • Layer combination easy * Difficult

  27. RASTER MODEL VECTOR MODEL

  28. RASTER MODEL VECTOR MODEL

  29. Applications of GIS Fields Activity 1. Agriculture (i) Crop acreage and production estimation . (ii) Monitoring and management from macro level to national level . (iii) Change detection of vegetated areas. 2. Archeology (i) Site description and scenario evaluation . 3. Forestry (i) Monitoring vegetation health . (ii) Analysis of deforestation and associated environmental hazards . (iii) Management , planning and optimizing extraction and replanting. (iv) Monitoring forest fire . 4. Epidemiology & (i) Location of disease in relation to environment factors. health

  30. 5. Commerce & (i) Market share analysis . business (ii) Insurance . (iii) Site location and target groups . 6. Tourism (i ) Location and analysis of facilities & attraction 7. Utilities (i) Location, management and planning of water, drains,gas, electricity telephones, cable services. (ii) Site elevation and costing : cut &fill, computing volumes of material. 8. Emergency Services (i) Optimizing fire, police & ambulance routing (ii) Improved understanding of crime & its location. 9. Defense agencies (I) Target site identification (ii) Tactical support planning (iii) Mobile command modeling (iv) Intelligence data integration

  31. 10. Environmental Management (i) Monitoring and management of Land degradation, waste land Mapping (ii) Land evaluation & rural planning (iii) Land Slides (iv) Desertification (v) Water quality and quantity (vi) Ground water potential mapping (vii) Mineral mapping potential (viii) Pollution monitoring (ix) Natural hazard assessment (x) Resource Management (xi) Environmental impact Assessment (xii) Monitoring Ocean Productivity THIS LIST IS ENDLESS…………….

  32. (f) Trends in GIS:- • Natural Resources Management • Telecom GIS • Automated mapping and Facility management (AM & FM) • Virtual 3-D GIS • Internet GIS / Web GIS • Spatial multimedia

  33. QUERIES AND SPATIAL ANALYSIS • QUERIES :- • Query method allows the user to interact with geographic database using pointing devices and key boards. • Queries are the most basic of analysis operations in which the GIS is used to answer simple and well defined to complex questions posed by the user. • EXAMPLES:- • Name the Feature • Getting information about a feature • Finding a feature • Selecting the features by building query expressions • Finding the highest and lowest value of an attribute • Hyper Linking

  34. Spatial Analysis: v      The principal objective of spatial data analysis is to transform and combine data from different sources / disciplines into useful information, to improve one’s understanding or to satisfy the requirements or objectives of decision makers. v      Spatial analysis is the crux (vital part) of Geographical Information Systems. v      Spatial analysis can reveal things that might otherwise be invisible. v      It involves analyzing, querying, manipulating, modeling and making new information available in the form of maps, reports, charts, etc. v      Effective spatial analysis requires an intelligent user, not just a powerful computer. v      In spatial analysis information on location is essential. Analysis carried out without knowledge of locations is not spatial analysis. For example, calculation of an average income for a group of people is not spatial analysis because it is no way depends on locations of the people. But calculation of the center of Hyderabad population is spatial analysis because the results depends on the knowledge where all Hyderabad residents are located.

  35. SPATIAL ANALYSIS METHODS • a. Single layer operations • b.Multi layer operation / topological overlay (Vector and Raster) link • c. Geometric Modeling • d. Network analysis • Surface analysis (3D Geographical Information Systems) • f.  Raster / Grid analysis • g.  Cost-benefit analysis • h. Location allocation

  36. 1. TOPOGRAPHY 2. BOUNDARIES 3. VEGETATION 4. ROADS 5. RIVERS 6. SOILS THEMATIC OVERLAY

  37. a. Single Layer Operation link This corresponds to queries that operate on a Single Data Layer. Ex. Create buffer around a road b. Multi Layer Operation link It corresponds to manipulation of spatial data on Multiple Data Layers. Ex. Soil and village i.e. to find out village wise soil distribution c. Geometric Modeling §Find distance between features. §         Find area, length, perimeter of objects §         Generate geometric buffers (for both vector and raster)

  38. d. Network Analysis Network analysis is used to find the shortest path between source and destination points. If a barrier exist on any segment between source and destination then the next alternate route is selected. Generally network analysis is applied to road network, pipe lines etc. The attribute table of roads may have fields like speed, impedance. Impedance is the obstacle / resistance / hurdles to the flow of traffic. Lower the impedance, higher the SPEED OF movement. e. Surface Analysis This analysis acts on 3D – Surface (TIN or DEM).  The following various maps and analysis are possible using surface analysis tools.  a.       * Creation of slope map link b.       * Creation of Aspect map (direction of slope ) link c.       * Visualization of 3D data for Landscape planning d.       * Create contour link e.       * Find the steepest path on a surface. f.        * Visibility analysis between different locations link g.       * Creation of profile graph. link h.       * Cut and fill Analysis f.

  39. Location and allocation Analysis * It involves two types of decisions where to locate the supply center and how to allocate demand for service. * This is used for location of Central Public facilities like Libraries, School, Dispensary etc. Its objective is to locate for maximum total accessibility.

  40. (g) GIS SOFTWARES:- Sl.No. Company Name Data Model DBMS 1 ESRI Arc Info,Arc Vew Vector Info, Oracle 2 MapInfo MapInfo Professinal Vector Dbase 3 I.T.C. ILWIS 2.2Win Raster Dbase 4 Intergraph M.G.E. Vector Dbase 5 Tydac Tech. SPans GIS Mixed Internal 6 I.I.T.,Mumbai GRAM++ Mixed MS Access 7 Auto desk Autocad map Vector Dbase 8 Geomedic Inc. Geo media Vector MS Access 9 PCI Geomatica Mixed Dbase 10 Clarke’s University IDRISI Raster Dbase 11 System Research Institute Geo-concept Vector Inbuilt/others

  41. Classification of GIS Soft wares Auto desk ESRI Intergraph MapInfo GE Small world 1 Internet Map Guide Arc IMS Geo media WebMap,Geo media Web enterprises Map X treme, MapXsite Small world Internet Application Server 2 Viewer Auticad LT Arc explover Geo media Viewer ProViewer Custom 3 Component Featured in Several Products Map Objects Part of Geomedia Map X, Map j Part of Small world GIS 4 Hand held On Site Arc Pad In development MapXtend Scout 5 Desktop World Arc View Geo Media Map Info Professoinal Spatial Intelligence 6 Professinal Auto CAD / world Arc Info Geo Media Pro Map Info Professional Small World GIS Based on the functionality and type GIS S/W are classified into 6 categories:-

  42. Internet GIS :- Internet GIS has the highest potential user base and lowest cost for user . This is because of the wide spread availability of the internet and market demand for greater access to geographic information . -- GIS software vendors have been quick to release products that harness the power of the internet . -- Most of the vendors develop GIS technology that integrates with web browsers and servers and use the hypertext transmission protocol (http) for communication . -- Internet GIS have the highest number of users . -- Initially, the internet GIS application focused on display and query application; but today, it is possible to perform standard GIS operations and make maps.

  43. Desktop GIS :- - Desktop GIS is gaining popularity day by day. - Desktop GIS focuses on data use, rather than data creation - It is an excellent tool for making maps, reports and charts - It adopts the Microsoft standards for inter-operability and user interface style - Desktop GIS enables to do a job faster, easily, economically - Earlier there was no provision of data creation /generation and hence no concept of topology. But due to advancement in technology and competition among commercial software companies, the above facilities have been added.

  44. Hand Held GIS :- Due to dramatic improvement in hardware design, it has become possible to develop GIS software for mobile and personal use on hand held systems . These palm and pocket devices support many display, query and simple analytical applications . All program and data are held in memory because of lack of hard disk. This provides fast access but with high cost Now, designers are thinking to develop compact Data storage structures.

  45. Viwer Components Internet GRAPH (Cost, Functionality, No. of users) Cost No. of users Internet Viewer Component Hand Held Desktop Professional Functionality

  46. T h a n k Y o u For your attention

  47. DISCUSSIONS

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