1. "GIS Concepts"

2. GIS Definition
Many expert used GIS for his own demand and that is the reason that they define GIS in that context.
Aronoff (1989) gives a general description of GIS as “any manual or computer-based set of procedures used to store and manipulate geographically-referenced data.”
More specifically, Aronoff (1989) defines GIS as "a computer-based system that provides four sets of capabilities to handle georeferenced data: i) data input ii) data management (data storage and retrieval) iii) manipulation and analysis iv) data output.”
Cower (1988) defines GIS as “a decision support system involving the integration of spatially referenced data in a problem solving environment”.

4. COMPONENTS OF GIS Hardware Software
Several components are involved in GIS technology.
Hardware
A computer and the associated accessories are essential for handling spatial data in GIS. These devices are collectively known as hardware like scanners, CPUs, Digitizers, Workstations & plotters etc.
Software
Software refers to the programmes that run on computers; these include programmes to manage the computer and to perform specific functions. For example, DBMS, Corel draw, ILWIS, Arc/view, Mapinfow, ERDAS Imagine, IDRISI and Arc/info are specialised software programmes designed to perform certain tasks. Continued………

5. Human Input (live ware)
Database
A central theme to GIS is the database. A GIS database deals with spatial data. GIS facilitate integration of spatial and attribute data and this makes GIS unique in contrast to other database systems. The beauty of GIS technology lies in the ability to assimilate divergent sources of data and analyse them.
Human Input (live ware)
People who work with GIS form the most important component. GIS constitute truly a interdisciplinary field and require varied backgrounds of expertise, depending upon the applications. In addition, for technical management, a Hardware Specialist, System Administrator, and Database Manager are required for corporating the GIS set-up.
Policy and Procedures
A methodology is must to derive the results users need. Basically, this includes spatial analysis for the particular application. By and large, this depends upon the institutional framework and its interest in exploiting GIS technology for decision-making

6. Geographic Information Systems
IDRISI
ILWIS
ARC/
INFO
PEOPLE
GIS
SOFTWARE
POLICY AND
PROCEDURES
FOR
RESOURCE
MANAGEMENT
HARDWARE
DATA

7. GIS Historical Development
CAD/CAM
Military Studies
Cartography
Remote Sensing
Spatial Mathematics
Urban Planning
Geography
Computer Science
Earth Science
Surveying and
Photogrammetry
Civil Engineering
GIS Historical Development

9. Components of GIS + GIS ABSTRACTION OR SIMPLIFICATION USERS SOFTWARE
DATABASE
TOOLS
THE REAL WORLD
RESULTS

10. FOUR Ms Modeling Measurements Mapping Monitoring Time-1 Time-2 Time-3
Landuse
Soil
Topography
GEOGRAPHIC INFORMATION SYSTEM
The four Ms. Measurement, Mapping, Monitoring and Modeling of environmental features and processes can be enhanced through the use of a GIS
Adapted from J.Stars and J.Estates
Time-1
Time-2
Time-3
Updating
Spatial
Analyses

11. GIS Hydrology Landuse Districts Topography Soils
A computer based system capable of holding and using data describing places on the earth’s surface
The real world consists of many geographies which can be represented as a number of related data layers.
Hydrology
Landuse
Districts
Topography
Soils
GIS
GIS IS SUPPORTING TOOL FOR DECISION MAKERS

12. HOW GIS WORKS GIS operations Geology Hydrology Thematic object
Point
Area
Line
-Analysis
Cartographic
processing
.- Generalization
- Symbolization
Thematic
object
selection
Hydrology
Soil
Attribute tables
Aerial photographs
Satellite images
Field Survey
GPS
Statistical tables
Maps
Real world
Decision makers

13. Topographic
REAL-WORLD
Contour lines
Parcels
MAPS AND SPATIAL DATA

14. Questions a GIS can answer
Location
Condition
Trends
Patterns
Modelling

19. Geographic Data

20. Types of GIS Vector GIS Raster GIS Hybrid GIS
Technology is moving towards hybrid GIS
Raster Vector Integration

21. Vector Representation
The Vector Data Model
Features of Spatial Object
Points (Example : Location of house)
Lines(Example : Railway)
Polygons (Examples : Forest area)
The location of features on the earth’s surface are referred to map positions using an XY coordinate system (termed a Cartesian Coordinate System).
PointA Singly XY pair
LineSeries of XY pair
PolygonA closed loop of XY coordinate pairs that define the boundary

22. Raster Representation
Row
Column
Cell Size
Resolution
Buildings
Road
River

23. Attribute Data District Name Area Population
Peshawar 395 sq. km. 6,75,341
Swabi 385 sq. km. 2,57,086
Dir lower 119 sq. km. 1,72,952
 Industry Information  Industry Information
 Agriculture Census  Education and Health

24. SPATIAL AND NON-SPATIAL DATA
City blocks Land use
001 Institutional
002 Commercial
003 Commercial
004 Residential
005 Residential
006 Residential
007 Industrial
008 Residential
009 Industrial
010 Industrial
011 Residential
012 Industrial
013 Residential
014 Residential
015 Residential
Map: City blocks
NON-SPATIAL DATA
SPATIAL DATA

25. THEN WHAT SHOULD BE THE BEST ROUTE, LEAVE IT UPTO GIS
Analysis
Analysis
Cadastral parcel
Alternative 1
Alternative 3
Alternative 2
National park
Risk area
Land-use
Soil
Slopes
Digital Terrain Model
Decision makers
Topography

26. Four Major GIS FunctionsŸ
data capture -
graphic data: digitised, converted from existing data -
attribute data: keyed-in, loaded from existing data files Ÿ
data storage and manipulation -
file management -
editing Ÿ
data analysis -
database query -
spatial analysis -
modelling Ÿ
data display -
maps -
reports

27. 1.INPUT OF DATA WHAT ARE THE FUNCTIONS INVOLVED IN GIS Data collection
(Both Geographical & Statistical)
Data verification
Data transfer
Data editing

28. 2.DATA STORAGE WHAT ARE THE FUNCTIONS INVOLVED IN GIS On hard disk
On floppy disk
On CDs

29. 3.MANIPULATION OF DATA WHAT ARE THE FUNCTIONS INVOLVED IN GIS
Cartographic function
a.Scale changes
b.Vector-Raster changes
c.Projection changes
d.Map embellishment like adding
north, title, scale and legend etc
(continued….)

30. 3.MANIPULATION OF DATA WHAT ARE THE FUNCTIONS INVOLVED IN GIS
Data integration (Core of GIS)
a.Maps over laying
b.Spatial transformation
c.Spatial aggregation
(continued……..)

31. HOW G.I.S. WILL ANALYSE THE DATA
Example: Selection of waste disposal site for
Peshawar city under the following conditions
1. The selected site should be located within 20 km distance
from the city center, but further than 300 meters from
any existing built-up area.
2. The site should be located on clay-rich soils, with a maximum
thickness of 5 meters and clay content greater than 50%.
3. The site should have an area of at least 2 hectares.
(Continue…..)

32. HOW G.I.S. WILL ANALYSE THE DATA
Example: Selection of waste disposal site for
Peshawar city under the following conditions
4. Should have an area, which do not have an important
economic or ecological value.
5. Site should be located on a terrain with slope less than
20 degree to prevent erosion and to assure accessibility.
6. Should be free from active landslides.

33. HOW G.I.S. WILL ANALYSE THE DATA
Following data are available for data input
a. Contour map indicated in degrees
b. Landuse map
c. Road map
d. Slide map with landslide distribution
e. City map
f. Geological map
FORMULAS WILL BE USED AS
Lslide=iff((slide=“dormant”)or(slide=“active”),1,0)
Luse=iff((landuse=“barren”)or(landuse=“forest”),1,0)

34. SELECTION OF SUITABLE SITE
FOR WASTE DISPOSAL

35. 3.MANIPULATION OF DATA WHAT ARE THE FUNCTIONS INVOLVED IN GIS
Feature measurement
a.Number of features
b.Calculate distance, area
c.Statistical analysis like crossing
of tables and correction

36. 4.DATA OUTPUT WHAT ARE THE FUNCTIONS INVOLVED IN GIS Data presentation
a.Maps
b.Tables
c.Diagrams
DATA TRANSFERING/DATA SHARING

37. Principal Components and Functions of an Ideal GIS

38. YOU SHOULD BE CLEAR IN MIND WHILE ENTERING DATA INTO COMPUTER
"Rubbish in"
"Rubbish out"

39. GEOGRAPHIC DATA Spatial and Non-Spatial data
There are two important components of geographic database: its geographic position and its attributes or properties. In other words, spatial data (where is it?) and attribute data (what is it?)
Analogue Data: A physical product displaying information
visually on paper like maps, aerial photos, imageries,
tabular data and written report etc.
Digital Data: Information derived from computer

40. Basic types of spatial Data
Maps model the real world with points, lines, and polygons. Symbols and labels describe the descriptive information about the geographic features.
Points
Points define the discrete locations of geographic features which are too small to illustrate as lines or polygons such as well or telephone poles. Points can be used to illustrate the locations of mountain peak or discrete elevation points.
Lines
Lines represent the linear features of geographic object too narrow to illustrate as polygons, such as streets and streams that have length but no area. Moreover, contour lines are represented as the lines
By using different symbols and labels, descriptive information of linear features are illustrated. For example: Roads are drawn with various line widths and patterns and colors to represent different road types, e.g., highway as wide solid red colour line, blue lines are used to illustrate the streams. The symbol can be used to illustrate the railway.
City streets are labeled with names and often address ranges.

41. Polygons
Polygons are closed features that represent the shape and location of homogeneous features such as landuse, forest types. Tone of the colour can be applied to illustrate the density of population, green color can be used to represent vegetation and blue colour can be used to illustrate lake.
Surfaces
A surface represents the elevation, presence or absence of something for every point on the piece of earth. The elevation models are best examples to illustrate as the surfaces.
Surfaces are typically represented on the maps as the series of isolines. Elevation contours, rainfall, temperature can be represented as the surface of isolines.
Surfaces can be represented as the Raster Elevation Model and Vector Elevation Model.

42. Geometry of Spatial Data
Point
Line
Area
surface

43. REPRESENTATION OF GEOGRAPHIC DATA
Vector Graphics:
Images are built-up from points, lines(segments) and areas (Polygons).
Each defined by pair of X-Y co-ordinates.
Preparing a map by digitization is converted into vector data in
computer.
Raster Graphics:
Images are built-up from cells which is called as Pixels.
In raster graphics, the smaller the area of land that each cell
represents, the higher the resolution of the data and higher the
spatial accuracy, ultimately the larger the files needed to store
the data.

45. SPATIAL DATA INPUT Scanning (automatic digitizing) Manual digitizingX Y
Scanning (automatic digitizing)
Editing
Raster model
Improving
Vectorizing
Apply attributes
Sensor X Y
Manual digitizing
Improving
Apply attributes
Vector model
Digital Landscape
Model

47. Features
Raster model)

48. Advantages and Disadvantages of the Raster and Vector Data Models
RASTER MODEL
VECTOR MODEL
Advantages -
easy and efficient overlaying
compatible with RS imagery
same grid cells for several attributes
Disadvantages
inefficient use of computer storage
errors in perimeter, area, and shape
difficult network analysis
inefficient projection transformations
loss of information when using large cells
less accurate (although attractive) maps
- efficient for network analysis
- efficient projection transformation
- accurate map output
- complex data structure
- difficult overlay operations
- not compatible with RS imagery

49. APPLICATION OF GIS Some typical examples of GIS applications are;
Canada was the pioneer in development of GIS as a result of innovations dating back to the early 1960s. Much of the credit goes to Roger Tomilson for the early development of GIS. Although the field of GIS has been around for the last 25 years the real potentials have become apparent only since the late 1980s. Afterwards widely used in USA, Canada & Western Europe.
Some typical examples of GIS applications are;
land-use planning and management e.g. Cadestral mapping, Urban growth, Landuse changes etc. S.O.P, SUPARCO, P.D.A, C.D.A, P.E & D)
oil & mineral exploration (O.G.D.C, Oil companies, P.G.S)
environmental impact studies
management of water resources (IIMI, AKRSP, WAPDA)
natural hazard mapping (FFC, NESPAK)
forestry and wildlife management (FMC, PFI, AKRSP)
soil degradation studies (Soil survey of Pakistan)
monitoring desertification
agricultural development
socio-economic survey and mapping (S.O.P & Primary education project in NWFP, Baluchistan, Sind, N.As & A.K.)

52. SELECTION OF SUITABLE ROUTE BETWEEN PESHAWAR AND KOHAT
Recreational
park ? ? ? ? ?
Swamp
Private
Parcel ? ? ? ? ?
Bara River ? ? ? ?