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Project 2 Presentation. Spatial Databases GIS Case Studies. Elizabeth Sayed Elizabeth Stoltzfus December 4, 2002. UC Berkeley: IEOR 215. Agenda. Spatial Database Basics Geographic Information Systems (GIS) Basics Case Studies. Spatial Database Basics. Common applications.
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Project 2 Presentation Spatial Databases GIS Case Studies Elizabeth Sayed Elizabeth Stoltzfus December 4, 2002 UC Berkeley: IEOR 215
Agenda Spatial Database Basics Geographic Information Systems (GIS) Basics Case Studies
Spatial Database Basics Common applications
Spatial Databases Background • Spatial databases provide structures for storage and analysis of spatial data • Spatial data is comprised of objects in multi-dimensional space • Storing spatial data in a standard database would require excessive amounts of space • Queries to retrieve and analyze spatial data from a standard database would be long and cumbersome leaving a lot of room for error • Spatial databases provide much more efficient storage, retrieval, and analysis of spatial data
Types of Data Stored in Spatial Databases • Two-dimensional data examples • Geographical • Cartesian coordinates (2-D) • Networks • Direction • Three-dimensional data examples • Weather • Cartesian coordinates (3-D) • Topological • Satellite images
Spatial Databases Uses and Users • Three types of uses • Manage spatial data • Analyze spatial data • High level utilization • A few examples of users • Transportation agency tracking projects • Insurance risk manager considering location risk profiles • Doctor comparing Magnetic Resonance Images (MRIs) • Emergency response determining quickest route to victim • Mobile phone companies tracking phone usage
Spatial Databases Uses and Users • Three types of uses • Manage spatial data • Analyze spatial data • High level utilization • A few examples of users • Transportation agency tracking projects • Insurance risk manager considering location risk profiles • Doctor comparing Magnetic Resonance Images (MRIs) • Emergency response determining quickest route to victim • Mobile phone user determining current relative location of businesses
Spatial Database Management System • Spatial Database Management System (SDBMS) provides the capabilities of a traditional database management system (DBMS) while allowing special storage and handling of spatial data. • SDBMS: • Works with an underlying DBMS • Allows spatial data models and types • Supports querying language specific to spatial data types • Provides handling of spatial data and operations
Core Spatial Functionality Taxonomy Data types Operations Query language Algorithms Access methods Spatial application Interface to spatial application Interface to DBMS SDBMS Three-layer Structure • SDBMS works with a spatial application at the front end and a DBMS at the back end • SDBMS has three layers: • Interface to spatial application • Core spatial functionality • Interface to DBMS DBMS
Spatial Query Language • Number of specialized adaptations of SQL • Spatial query language • Temporal query language (TSQL2) • Object query language (OQL) • Object oriented structured query language (O2SQL) • Spatial query language provides tools and structures specifically for working with spatial data • SQL3 provides 2D geospatial types and functions
Spatial Query Language Operations • Three types of queries: • Basic operations on all data types (e.g. IsEmpty, Envelope, Boundary) • Topological/set operators (e.g. Disjoint, Touch, Contains) • Spatial analysis (e.g. Distance, Intersection, SymmDiff)
Spatial Data Entity Creation • Form an entity to hold county names, states, populations, and geographies CREATE TABLE County( Name varchar(30), State varchar(30), Pop Integer, Shape Polygon); • Form an entity to hold river names, sources, lengths, and geographies CREATE TABLE River( Name varchar(30), Source varchar(30), Distance Integer, Shape LineString);
Example Spatial Query • Find all the counties that border on Contra Costa county SELECT C1.Name FROM County C1, County C2 WHERE Touch(C1.Shape, C2.Shape) = 1 AND C2.Name = ‘Contra Costa’; • Find all the counties through which the Merced river runs SELECT C.Name, R.Name FROM County C, River R WHERE Intersect(C.Shape, R.Shape) = 1 AND R.Name = ‘Merced’; CREATE TABLE County( Name varchar(30), State varchar(30), Pop Integer, Shape Polygon); CREATE TABLE River( Name varchar(30), Source varchar(30), Distance Integer, Shape LineString);
Geographic Information System (GIS) Basics Common applications
GIS Applications • 1. Cartographic • Irrigation • Land evaluation • Crop Analysis • Air Quality • Traffic patterns • Planning and facilities management • 2. Digital Terrain Modeling • Earth science resources • Civil Engineering & Military Evaluation • Soil Surveys • Pollution Studies • Flood Control • 3. Geographic objects • Car navigation systems • Utility distribution and consumption • Consumer product and services
GIS Data Format • Modeling • Vector – geometric objects such as points, lines and polygons • Raster – array of points • Analysis • Geomorphometric –slope values, gradients, aspects, convexity • Aggregation and expansion • Querying • Integration • Relationship and conversion among vector and raster data
GIS – Data Modeling using Objects & Fields (0,4) (0,2) (0,0) (2,0) (4,0) Object Viewpoint Field Viewpoint Pine: 0<x<4; 2<y<4 Fir: 0<x<2; 0<y<2 Oak: 2<x<4; 0<y<2 Source: “Spatial Pictogram Enhanced Data Models pg 79
Conceptual Data Modeling • Relational Databases: ER diagram • Limitations for ER with respect to Spatial databases: • Can not capture semantics • No notion of key attributes and unique OID’s in a field model • ER Relationship between entities derived from application under consideration • Spatial Relationships are inherent between objects • Solution: Pictograms for Spatial Conceptual Data-Modeling
Pictograms - Shapes • Types: Basic Shapes, Multi-Shapes, Derived Shapes, Alternate Shapes, Any possible Shape, User-Defined Shapes * N 0, N !
Extending the ER Diagram with Spatial Pictograms: State Park Example Standard ER Diagram Spatial ER Diagram LineID RName RName Supplies_to River River PolygonID Supplies_to FoName FoName FacName Touches FacName Facility Forest Facility Forest Belongs_to Belongs_to PointID Within Monitors Monitors Fire Station Fire Station FiName FiName PointID
Case Studies Specific applications of spatial databases
Objective: To predict the spatial distribution of the location of bird nests in the wetlands Location: Darr and Stubble on the shores of lake Erie in Ohio Focus Vegetation Durability Distance to Open Water Water Depth Assumptions with Classical Data mining Data is independently generated – no autocorrelation Local vs. global trends Spatial accuracy Predictions vs. actual Impact Case Study: Wetlands Location of Nests Actual Pixel Locations Case 1: Possible Prediction Case 2: Possible Prediction Source: What’s Spatial About Spatial Data Mining pg 490
Case Study: Green House Gas Emission Estimations • Objective: • To assess the impact of land-use and land cover changes on ground carbon stock and soil surface flux of CO2, N2O and CH4 in Jambi Province, Indonesia • Methodology: • Initiated by development of land-use/land cover maps and followed by field measurements • Spatial database construction development based on 1986 and 1992 land-use/land cover maps that developed from Landsat MSSR and SPOT • Weight of sample components of the tree and streams, branches, twigs, etc were estimated from equations and literature • Emission rates were developed by plotting and analyzing collected air samples • Field data measurements and GIS spatial data were combined using a Look Up Table of Arc/Info. Source: “Spatial Database Development for green house gas emission Estimation using remote sensing and GIS”
Case Study: Green House Gas Emission Estimations (cont) • Results: • Able to quantitatively compare emission changes between 1986 to 1992: • Determined that there was a loss of 8.3 million tons of Carbon • Proportion of primary forest decreased from 19.3% to 12.5% • Showed 24% of primary forest was converted into logged forest, shrub, cash crops • Greenhouse gas emission varied depending on the site condition and season. • Process gave impacts of greenhouse gas on the soil surface
Case Study: Pantanal Area, Brazil • Objective: To assess the drastic land use changes in the Pantanal region since 1985 • Data Source: • 3 Landsat TM images of the Pantal study area from 1985, 1990, 1996 • A land-use survey from 1997 • Assessment Methodology: • Normalized Difference Vegetation Index (NDVI) was computed for each year • NDVI maps of the three years combined and submitted to multi-dimensional image segmentation • Classified vegetation • Produced a color composite by year that identified the density of vegetation Source: Integrated Spatial Databases pg 116
Conclusion • Many varied applications of spatial databases • Stores spatial data in various formats specific to use • Captures spatial data more concisely • Enables more thorough understanding of data • Retrieves and manipulates spatial data more efficiently and effectively
Problem 1 Solution a) Find all cities that are located within Marin County. SELECT C2.Name FROM County C1, City C2 WHERE Within(C1.Shape, C2.Shape) = 1 AND C1.Name = ‘Marin’; b) Find any rivers that borders on Mendocino County. SELECT R.Name FROM County C, River R WHERE Touch(C.Shape, R.Shape) = 1 AND C.Name = ‘Mendocino’; c) Find the counties that do not touch on Orange County. SELECT C1.Name FROM County C1, County C2 WHERE Disjoint(C1.Shape, C2.Shape) = 1 AND C2.Name = ‘Orange’;
Problem 2 Solution ClosetID Length Type Closet Hallway RoomID Accesses HallID Belongs_To Room Belongs_To FurnID Belongs_To Furniture Name