geographic information systems cive 1188 hanadi rifai, phd, pe civil and environmental engineering...
TRANSCRIPT
![Page 1: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/1.jpg)
Geographic Information SystemsCIVE 1188
Hanadi Rifai, PhD, PE
Civil and Environmental Engineering
University of Houston
![Page 2: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/2.jpg)
Where did GIS come from?
• GIS is built upon knowledge from geography, cartography, computer science and mathematics
• Geographic Information Science is a new interdisciplinary field built out of the use and theory of GIS
![Page 3: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/3.jpg)
Defining GIS
• Different definitions of a GIS have evolved in different areas and disciplines
• All GIS definitions recognize that spatial data are unique because they are linked to maps (Space matters!)
• A GIS at least consists of a database, map information, and a computer-based link between them
![Page 4: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/4.jpg)
Spatial and non-spatial data
Crimes during 1995Date Location Type1/22 123 James St. Robbery1/24 22 Smith St. Burglary2/10 9 Elm St. #4A Assault2/13 12 Fifth Avenue Breaking
& Entering
Part No. Quant. Desc.1034161 5 Wheel spoke1051671 1 Ball bearing1047623 6 Wheel rim1021413 2 Tire1011210 3 Handlebars
Figure 1.1 Two databases. A database contains columns (att ributes) and rows (records). The bicycleparts list on the left is not spatial. The parts could be located anywhere. The list of crimes on the rightis spatial because one of the at tributes, the street address, locates the crimes on a map. This list couldbe used in a GIS.
![Page 5: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/5.jpg)
Map Overlay
Figure 1.3 Map overlay as presented in Design with Nature by Ian McHarg. Each transparent layer map“blacked out” areas excluded as unsuitable locations.
SOILS
PARKS
URBAN
SOLUTION MASK
FOREST
![Page 6: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/6.jpg)
The Feature Model
BM 123
r
L a k e
Figure 1.2 The Feature Model: Examples of a point feature (elevation bench mark), a line feature (riv-er) and an area feature (lake).
POINT LINE AREA
FEATURES
![Page 7: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/7.jpg)
A Brief History of GIS• GIS’s origins lie in thematic cartography (manual map overlay) • Computer cartography advances in 1950s and 1960s• Early influential data sets were the World Data Bank and the
GBF/DIME files. Early systems were CGIS, MLMIS, GRID and LUNR
• The Harvard University ODYSSEY system was influential due to its topological arc-node (vector) data structure
• GIS was significantly altered by (1) the PC and (2) the workstation • During the 1980s, new GIS software could better exploit more
advanced hardware • User Interface developments led to GIS's vastly improved ease of use
during the 1990s• During the 1980s, new GIS software could better exploit more
advanced hardware
![Page 8: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/8.jpg)
Sources of Information on GIS
• The amount of information available about GIS can be overwhelming
• Sources of GIS information include journals and magazines, books, professional societies, the World Wide Web, and conferences
• GIS has Web Home pages, network conference groups, professional organizations, and user groups
• Most colleges and universities now offer GIS classes in geography departments
![Page 9: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/9.jpg)
Organizing Data and Information
• Information can be organized as lists, numbers, tables, text, pictures, maps, or indexes.
• Clusters of information called data can be stored together as a database.
• A database is stored in a computer as files.
![Page 10: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/10.jpg)
Flat File Database
Record Value Value Value
Attribute Attribute Attribute
Record Value Value Value
Record Value Value Value
![Page 11: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/11.jpg)
Geographic Coordinates as Data
![Page 12: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/12.jpg)
Building complex features• Simple geographic features can be used to
build more complex ones. • Areas are made up of lines which are made up
of points represented by their coordinates.• Areas = {Lines} = {Points}
![Page 13: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/13.jpg)
Areas are lines are points are coordinates
![Page 14: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/14.jpg)
Basic properties of geographic features
![Page 15: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/15.jpg)
GIS Analysis
• Much of GIS analysis and description consists of investigating the properties of geographic features and determining the relationships between them.
• Two types of systems:– Raster or pixel based– Vector or arc based
![Page 16: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/16.jpg)
RASTER
• A grid or raster maps directly onto a programming computer memory structure called an array.
• Grids are poor at representing points, lines and areas, but good at surfaces.
• Grids are good only at very localized topology, and weak otherwise.
• Grids are a natural for scanned or remotely sensed data.• Grids suffer from the mixed pixel problem.• Grids must often include redundant or missing data.• Grid compression techniques used in GIS are run-length encoding
and quad trees.
![Page 17: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/17.jpg)
Raster Data Formats
• Most raster formats are digital image formats.
• Most GISs accept TIF, GIF, JPEG or encapsulated PostScript, which are not georeferenced.
• DEMs are true raster data formats.
![Page 18: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/18.jpg)
The Vector Model
• A vector data model uses points stored by their real (earth) coordinates.
• Lines and areas are built from sequences of points in order.
• Lines have a direction to the ordering of the points.
• Polygons can be built from points or lines.
• Vectors can store information about topology.
![Page 19: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/19.jpg)
VECTOR• At first, GISs used vector data and cartographic spaghetti
structures.• Vector data evolved the arc/node model in the 1960s.• In the arc/node model, an area consist of lines and a line
consists of points.• Points, lines, and areas can each be stored in their own files,
with links between them.• The topological vector model uses the line (arc) as a basic
unit. Areas (polygons) are built up from arcs.• The endpoint of a line (arc) is called a node. Arc junctions are
only at nodes.• Stored with the arc is the topology (i.e. the connecting arcs
and left and right polygons).
![Page 20: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/20.jpg)
TOPOLOGY
• Topological data structures dominate GIS software.
• Topology allows automated error detection and elimination.
• Rarely are maps topologically clean when digitized or imported.
• A GIS has to be able to build topology from unconnected arcs.
• Nodes that are close together are snapped.
• Slivers due to double digitizing and overlay are eliminated.
![Page 21: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/21.jpg)
Basic arc topology
n1
n2
123 A
B
Arc From To PL PR n1x n1y n2x n2y1 n1 n2 A B x y x y
Topological Arcs File
Figure 3.5 A topological structure for the arcs.
![Page 22: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/22.jpg)
Finding Existing Map Data
• Map libraries
• Reference books
• State and local agencies
• Federal agencies
• Commercial data suppliers e.g. GDT, Thompson, ETAK
• World Wide Web
• GIS vendors package data with products.
![Page 23: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/23.jpg)
USGS: National Mapping
![Page 24: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/24.jpg)
Terrain dataDEMDLG
ContoursDCW
Contours
![Page 25: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/25.jpg)
U.S. Bureau of the Census
![Page 26: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/26.jpg)
NOAA Weather and other data
![Page 27: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/27.jpg)
• Distributed active archive center
• Sioux Falls, SD
• Operated by USGS
Eros Data Center
![Page 28: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/28.jpg)
Digitizing• Captures map data
by tracing lines from a map by hand
• Uses a cursor and an electronically-sensitive tablet
• Result is a string of points with(x, y) values
![Page 29: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/29.jpg)
Scanning
• Places a map on a glass plate, and passes a light beam over it
• Measures the reflected light intensity
• Result is a grid of pixels
• Image size and resolution are important
• Features can “drop out”
![Page 30: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/30.jpg)
Field data collection
![Page 31: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/31.jpg)
Attribute data
• Logically can be thought of as in a flat file
• Table with rows and columns• Attributes by records• Entries called values
![Page 32: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/32.jpg)
Database Management Systems• Data definition module sets constraints on the
attribute values• Data entry module to enter and correct values• Data management system for storage and retrieval• Legal data definitions can be listed as a data
dictionary• Database manager checks values with this
dictionary, enforcing data validation.
![Page 33: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/33.jpg)
Retrieval Operations
Searches by attribute: find and browse.
Data reorganization: select, renumber, and sort.
Compute allows the creation of new attributes based on calculated values.
![Page 34: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/34.jpg)
The Big Eight
• Form the bulk of operational GIS in professional and educational environments
• There are some significant differences between these “big eight” systems.
![Page 35: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/35.jpg)
Arc/Info
ESRIRedlands, CAArc/InfoMarket leaderworkstation (mostly)remarkable functionalitymany formats supportedArcEditArcGRIDArcPlotINFO
![Page 36: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/36.jpg)
ArcView
Versions 1-3, 3.1PC WindowsAvenueWeb linksMap ObjectsExtensions
![Page 37: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/37.jpg)
AutoCAD MAP
Windows all versionsSQL DBF AccessExtension to AutoCADMenu-basedMassive installed baseAdded grid, projection & topology supportDB links good.3D links good
![Page 38: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/38.jpg)
GRASS
First UNIX GISDeveloped by ArmyCorps of EngineersUNIX functionalityMany unique functionsFree until recentlyMany data setsBaylor University now supports
![Page 39: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/39.jpg)
IDRISI
Developed at ClarkUniversity, Worcester MAOriginal in PASCAL, withopen codeDevelopment uses a specialtyWindows/DOSSpatial analysis/stats extensions
![Page 40: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/40.jpg)
Maptitude
Caliper CorporationConsultancyTRANSCAD and GIS+Many network solutionsWindowsImport/ExportAddress matching
![Page 41: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/41.jpg)
Microstation MGE
CAD software with GISextensionsIntergraph Corp, Huntsville ALUses Windows NTMany parcel applicationsWeb extensions, server tools etc.
![Page 42: Geographic Information Systems CIVE 1188 Hanadi Rifai, PhD, PE Civil and Environmental Engineering University of Houston](https://reader031.vdocuments.site/reader031/viewer/2022013105/56649ead5503460f94bb4fd5/html5/thumbnails/42.jpg)
MapInfo
Based in Troy, NYMapping functionsLimited GIS functionalityUses Visual BasicMany applicationsFavored for 911, field