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GNR605: Principles of Geographic Information Systems Surya S. Durbha, PhD Professor CSRE, IITB  Outline ❖ Background ❖ Course Structure ❖ Introduction to GIS ❖ Summary Earth Observation from Multiple Vantage Points...

GNR605: Principles of Geographic Information Systems Surya S. Durbha, PhD Professor CSRE, IITB  Outline ❖ Background ❖ Course Structure ❖ Introduction to GIS ❖ Summary Earth Observation from Multiple Vantage Points ❑ Multiple vantage points for Ear observation leads to widesprea real time sensors and multiple archives of imagery and other datasets.  Linkages GIS Image Processing  Linkages GIS CAD/Engineering  Keywords ❒ Geographical Information Systems Spatial Data, Vector, Raster, Spatial Data Geoinformatics Indexing, Interpolation, Information ❒ Networks, DTM, TIN Systems, Computer ❒ Spatial Data Infrastructures, Data Science, Integration Remote Sensing, Geography, Mathematics  GNR605: Course consists of two modules Module 1 (before mid-term) ❑ Introduction to GIS ❑ Concept of Spatial Data ❑ Spatial Data Sources ❑ Coordinate Systems ❑ Map Projections ❑ Spatial Data Models, Vector Data Structures & Topology ❑ Raster Analysis, Vector Analysis, Spatial Relations ❑ Database Management System (DBMS), Spatial Databases  GNR605: Course consists of two modules Module 2 (after mid-term) ❑ Spatial Data Indexing ❑ Spatial Data Interpolation ❑ DTM, TIN ❑ Network Analysis ❑ Spatial Data Accuracy ❑ Applications  GNR605: Examination Pattern ❑ Projects (1) (weightage: 15%) ❑ Assignments (2) (weightage: 7.5% each) ❑ Critical review of papers, developing R-code for Interpolation. ❑ Mid Semester (weightage: 25%) ❑ Paper and Pencil type (closed book) ❑ End Semester (weightage: 45%) ❑ Paper and Pencil type (closed book)  Overview and Definition of GIS GIS is a new discipline generating massive interest worldwide. During the last 3 decades, there has been a very rapid rate of theoretical, technological, and organizational development in the GIS field GIS is an interdisciplinary area used by heterogeneous groups  Overview and Definition of GIS It brings together the ideas developed in various fields Focus of GIS activity centers around ▪ Hardware and software ▪ Information processing ▪ Applications  What is Information? Information is derived from the interpretation of data, which are symbolic representation of features. What is knowledge? The value of information depends on its timeliness, the context in which it is applied, and cost of collection, storage, manipulation and presentation. Information is a valuable asset, which can be bought and sold for a price.  Information Systems are of two types Transaction processing systems o Emphasis on recording, updating and retrieving as per the occurrence of operations o Operate in on-line or batch mode and follows well defined procedures Example : Banking and Airline Reservation Systems Decision Support System o Emphasis on manipulation, analysis and particularly modeling to support decision makers. o Used in market analysis, resources planning, defence etc. GIS belongs to the second type! https://www.terra.gr/wp-content/uploads/2017/05/SDSS-1-1.jpg http://proceedings.esri.com/library/userconf/proc97/proc97/to500/ pap486/p4861.gif  What is GIS? ❑ A Geographical Information System is a tool, which can accept large volumes of spatial data derived from a variety of sources, retrieve, manipulate, analyze and display them according to user-defined specifications.  Selected Definitions of GIS ❑ DoE (1987) - A system for capturing, storing, checking, manipulating, analysing and displaying data which are spatially referenced to the Earth. ❑ Aronoff (1989) - Any manual or computer based set of procedures used to store and manipulate geographically referenced data ❑ Carter (1989) - An institutional entity, reflecting an organizational structure that integrates technology with a database, expertise and continuing financial support over time ❑ Parker (1988) - An information technology which stores, analyses, and displays both spatial and non-spatial data ❑ Dueker (1979) - A special case of information systems where the database consists of observations on spatially distributed features, activities, or events, which are definable in space as points, lines, or areas. A GIS manipulates data about these points, lines and areas to retrieve data for adhoc queries and analyses  Selected Definitions of GIS ❑ Smith et al. (1987) - A database system in which most of the data are spatially indexed, and upon which a set of procedures operated in order to answer queries about spatial entities in the database. ❑ Ozemoy, Smith and Sicherman (1981) - An automated set of functions that provides professional with advanced capabilities for the storage, retrieval, manipulation and display of geographically located data ❑ Burrough (1986) - A powerful set of tools collecting, storing, retrieving at will, transforming and displaying spatial data from the real world ❑ Cowen (1988) - A decision support system involving the integration of spatially referenced data in a problem-solving environment ❑ Koshkariov, Tikunov and Trofimov (1989) - A system with advanced geo-modeling capabilities ❑ Devine and Field (1986) - A form of MIS [Management Information System] that allows map display of the general information  What is GIS? “Systems” Definition People Hardware Administrators Computers Managers Networks GIS Technicians Graphic Devices Application Experts Software End Users GIS Software Consumers Database Approaches Software Guidelines OS Software Specifications Network Software Standards Data Procedures Vector Data Raster Data Image Data Attribute Data  Alternative names of GIS o Multipurpose geographical data system o Multipurpose input land use system o Computerised GIS o System for handling natural resources inventory data o Image-based information system o Land resource information system o Planning information system o Resource information system o Natural resource management information system o Spatial data handling system o Spatial data management and comprehensive analysis system o Geographically referenced information system o Spatial information system o Environmental information system o Automated GIS o Land information system o Automated mapping and facilities management o Knowledge based GIS  Why GIS Matters ❑ Almost everything happens somewhere ❑ Knowing where some things happen is critically important o Position of administrative boundaries o Location of infrastructure facilities o Routing vehicles o Management of natural resources o Monitoring development schemes http://en.es-static.us/upl/2011/02/smart_grid_esri_300.jpg  GI is Special ❑ Multidimensional ❑ Voluminous ❑ Requires projection to flat surface ❑ Unique analysis methods ❑ Analyses require data integration ❑ Data updates are expensive and time consuming ❑ Map displays require fast data retrieval http://skagit.meas.ncsu.edu/~helena/gmslab/viz/movies/chal3d.mpg http://gisgeek.pdx.edu/G424-GIS/image_data/ Understanding%20Imagery%20and%20Image%20Analysis%20-%20Lessons_files/t1exp1_files/  Where does Geo Information(GI) come from? Geography Cartography CAD and computer graphics Surveying and photogrammetry Remote Sensing and space technology https://cdn-focjb.nitrocdn.com/RzUKmdHdCIStbdZtPxHaJLNXjEKZQBeM/assets/images/optimized/rev-146d1b6/wingtra.com/wp-content/uploads/lidar-vs-photogrammetry-drone.jpg  What GIS can do? ❑ Predict drought conditions. ❑ Monitor water resources. ❑ Visualize remote-sensing data. ❑ Model data from many sources. ❑ Evaluate economic and environmental impact. ❑ Data sharing http://t3.gstatic.com/images? q=tbn:ANd9GcRS24yTI1zMxV9oZwGbNH6PYfBd http://t2.gstatic.com/images?q=tbn:ANd9GcQC5PXrDUJk3iHqFEpTugf1_8MFh5w2nTvEzaE7CMKchYwE9lm2 PH3wJ8MBG_biqjqSoZrNhrWOUA  What GIS can do? ❑ How many gas stations (points) are located in areas with permeable soil above aquifer X? ❑ How many miles of roads (line) pass through areas of salt-sensitive vegetation (polygon)? ❑ How much of the area within 100 feet of the river is forested? ❑ Show the parcels that are over 100 acres, near the highway, not near wetlands or water, and zoned industrial ❑ Retrieve population data for the census blocks within the watershed.  What GIS can do? (Advanced Spatial Queries) ❑ How many houses can be built here under each of the zoning options we are considering? ❑ What fire company is closest to this house that just called 911, and what’s the fastest (not shortest) route to get there? Print the driving directions. ❑ Draw a corridor from A to B that crosses the least amount possible of wetlands, steep slopes, powerful landowners. Avoid certain areas altogether.  Layered Representation of Spatial Data ❑ Data of a particular level of classification, such as roads or drainage networks are grouped into separate layers or coverages. ❑ Layered representation of spatial data is common to both vector and raster models ❑ Layers of information can be merged to form a generalized representation – roads and railway lines combined to form transportation network layer. Background: Example  Layers Layer is a collection of similar features ▪Two kinds of operations: single map layer (Intra-layer) between map layers - OVERLAY (Inter- layer) Image source: ESRI Environmental Attributes Map Layer Geology Hazard Areas Existing Land Use Noise Contours Floodplain Soils Vegetation Surficial Hydrology EI Study Areas Planning Study Index Reference  How can the computer understand the relationships one sees on a map?  Modeling: Entity Relations Source: Bernhardsen, Tor. (1999). 2nd Ed. Geographic Information Systems: An Introduction. pp 40.  Real World Collection of all facts, whether they are known by mankind or not. Facts in the real world are understood in terms of their essence.  Conceptual Conceptual World World Shows things we can easily identify: doors, paths, bricks, a roof, the house of a friend, and so forth.  Geospatial World a brick house is simplified to a 3- dimensional The world, even at the conceptual level, is too polyhedron, full of complex shapes, patterns, details, and change to model realistically. These a house with another complexities are eliminated in the Geospatial surface material is World, and replaced with abstractions that are simplified to its footprint usually temporally and spatially static as well. polygon.  Representing Reality ❑ Spatial data consist of digital representations of discrete (spatial) objects. ❑ The features shown on a map, e.g. lakes, buildings and contours can be thought of as discrete objects. ❑ Thus the contents of a map can be captured in a data base by turning map features into data base objects (entities). Many of the features shown on a map are fictitious and do not exist in the real world.  Representing Reality ❑ For example, contours do not really exist, but houses and lakes are real objects. The contents of a spatial data base include: ▪ digital versions of real objects (e.g. lakes), ▪ digital versions of artificial map features (e.g. contours), ▪ artificial objects created for the purposes of the data base (e.g. pixels).  Multiple Representations A data model is essential to represent geographical data in a digital data base. There are many different data models. The same phenomenon may be represented in different ways, at different scales and with different levels of accuracy. Thus there may be multiple representations of theMultiple same geographical phenomenon. representations of spatial data  LandCapability Soil Spatial Roads Data Layers VillagesBnd Location Landuse  What Does A GIS Do? GIS can answer the following questions: 1. Location - What is at a given location? 2. Condition - Where does it occur? 3. Routing - What is the best way? 4. Trend - What has changed? 5. Pattern - What is the pattern? 6. Modeling - What happens if ? APPLICATIONS ▪ Resources Management ▪ Transportations Management ▪ Landuse Planning ▪ Telecommunication ▪ Agriculture ▪ Mining ▪ Forestry ▪ Government Agencies ▪ Water Resources Management ▪ Defence ▪ Rural/Urban Planning ▪ Emergency Operations ▪ Environmental Management ▪ Crime Management ▪ Risk Management ▪ Epidemiology ▪ Business /Marketing ▪ Archaeology ▪ Real Estate ▪ Facility Mapping  Who needs access to coordinated geographic information? ▪ Land Records Adjudication ▪ Disaster Response ▪ Transportation Management ▪ Water, gas & electric planning ▪ Public Protection ▪ Defense ▪ Natural Resource Management ▪ Telecommunications Infrastructure ▪ Economic Development ▪ Civic Entrepreneurs ▪ Regional Stewards  Business of GIS ❑ GIS industry is worth over $16 billion o Software o Data o Services o Publishing o Education  GIS Software Classification Number of Cost Users Internet Viewer Component Hand-held Desktop Professional Functionality 3D Visualization  Future Generic GIS Internet Enterprise Browsers Applications Web Web Server Broker Services ( built on.Net, SOAP/XML, Java API) Dallas Delhi Durban Source: Reza Wahadj, CSIG04, with mods. Databases  Summary ❑ Understanding GIS requires consideration of science, systems and studies ❑ GIS provides a framework to manage the world ❑ The real value of GIS is its problem solving capability ❑ The future of GIS is bright ‘Much of the life of the mind consists in applying concepts to things’ (Fodor 1998:24)