Download Geographic Information Systems - Centre for Modeling and Simulation

Center for Modeling & Simulation
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Introduction to GIS
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General Definitions
Concept of space and time
History
Components
Objectives / why use GIS
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IT can be a physical entity like a solar system or a conceptual
entity like a democratic political system
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All the systems have following characteristics
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Constructed to achieve certain basic objectives or functions
Their continuing existence depends on the ability to satisfy the
intended objectives
Composed of many interrelated parts, which may be operational
systems themselves
They operate individually and interact with one another according
to certain rules
What is an Information System
 It is a special class of systems
 Collection of data and tools for working with those data
which are in analog or digital format about the
phenomenon in the real world
 Has specific objectives of collecting, storing, analyzing
and presenting information in a specific manner
GIS as an Information System
 It is a special class of Information system
 Word Geographic has two implications as “earth” and
“Geographic space”
• “Earth” implying all the data are pertinent to earth’s features and
resources including human activities associated with these features
• “Geographic space” relates to the system developed to solve the
geography i.e location distribution, pattern and relationship within a
specific geographical framework reference
 This makes it a unique system as it focuses on geographic data
and their applications for spatial problems
Information System
Nonspatial
Spatial
accounting/ banking etc
Geographic Information Systems
Other spatial
information
systems
Eg CAD/CAM
Other Geographic information
systems
Socioeconomic
information
system
Biophysical
Information
system
Land
Information
systems
Data: collection of facts or figures relating to places, people, things, events and
concepts represented as numerical values, alphanumeric characters, symbols and
signals
Information: data transferred in a form meaningful to the user through
structuring, formatting, conversion and modeling
Knowledge: Using the Knowledge the user transfers the data into information to
aid the decision making
Intelligence: When the user deploys the knowledge to formulate principles and
perceive relationships
special form of spatial data characterized by
Reference Geographic space i.e data registered to coordinate
system
Representation at geographic scale i.e data are normally recorded at
relatively small scales
Grid co-ordinate
Place name
Latitude / Longitude
Post code
Description
Distance & bearing
Kingston Centre for GIS
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A system of hardware, software and procedures designed to
support the capture, management, manipulation, analysis,
modeling and display of spatially referenced data for solving
complex planning and management problems (Rhind, 1989).
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A computer system capable of assembling, storing,
manipulating and displaying geographically referenced
information (USGS, 1997)
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A set of computer based systems for managing geographic
data and using this data to solve spatial problems.
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Spatial information is always related to geographic space
and time
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Geographic space is the space of topography,
landuse/landcover, climatic, cadastral and other features
of the topographic world.
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Geographic time is the time whose effects can be
observed in this geographic space
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Thus GIS data consists of spatio-temporal data that can be
described, measured and stored in the information system
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Dates back to 1960s
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Initially developed by US Bureau of Census, USGS, ESRI,
Canadian Geographic Information systems and notable
organizations in U.K.
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In early 1970’s table data structures to store and analyze
map data became dominant creating topology in GIS
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During 1980’s the minicomputers and workstations
become dominant and the relational database became
standard for the spatial data structures
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1990’s recognition of geoinformatics as a professional
activity
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Commercial agencies like ESRI, Intergraph, Laserscan,
Autodesk etc started developing the commercial products
Stage of
Formative years
development
Maturing technology
GI infrastructure
Time Frame
1960-1980
1980-mid.1990s
Mid.1990s-present
Technical
environment
•Mainframe computers
•Proprietary software
•Proprietary data structures
•Mainly raster-based
•Mainframe and minicomputers
•Geo-relational data structure
•Graphical user interface
•GPS, redefinition of datum
remote sensing
•Workstations and PCs
•Network/Internet
•Open system design
•Multimedia
•Data integration
•Enterprise computing
•Object related data
model
Major users
•Government
•Universities
•Military
•Government
•Universities
•Utilities
•Business
•Military
•Government
•Universities
•Utilities
•Business
•Military
•General public
Major
application
areas
•Land and resource
management
•Census
•Surveying and mapping
•Land and resource
management
•Census
•Surveying and mapping
•Facilities mapping
•Market analysis
•Land and resource
management
•Census
•Surveying and mapping
•Facilities mapping
•Market analysis
•Utilities
•Geographic data
browsing
Hardware
Software
data
People
Hardware
Platforms
Input device
Output device
Personal
computers
Scanners
Printers
workstations
Digitizers
Plotters
Minicomputers
Tapes /
CD’s
Mainframe
Keyboard /
Monitors
Hardware
Software
Data
People
Software
Input
modules
editing
Analysis
module
Modeling
capability
Hardware
Software
data
People
Data
Attribute
data
Spatial
Data
Remote
Sensing
data
Global
database
GPS
Hardware
Software
data
People
GIS specialist
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General GIS users
Engineers/planners
Database administration
Application programming
System analysis and design
Project management
Geographic Information
viewers
Scientist
Traffic and weather condition
Facility managers
Property assessment I
Resource planners
Locate business and services
Land administrators
education
Lawyers
Point data
Vector data
Raster data
Attribute data
e.g. wells, sample sites, huts, schools, clinics
Simple
Complex
Curve
Network
Attached to
Points
Lines
Polygons
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Maximise the efficiency of planning and decision making
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Provides efficient means for data distribution and handling
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Elimination of redundant data base – minimise duplication
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Capacity of integrate information from many sources
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Complex analysis/query involving geographical referenced
data to generate new information
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What Exists at a particular location --- Location
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Identifies locations where certain conditions exist --- Condition
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What has changed since --- Trends
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What spatial pattern exists --- Patterns
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What if ……? --- Modeling