Introduction to Geographical Information System (GIS) for the Egyptian Railway System Project

1. Geographic Information System (GIS)
Eng. Ismail El Gayar

2. What Is GIS??
• Is any system that captures, stores, analyzes,
manages, and presents data that are linked to
location.
• is the merging of cartography and database
technology

3. Geographical Information
System Modules
• Database
• Map information
• Computer-based link between them

4. Geographical Information System
This technology has developed from:
– Digital cartography and CAD
– Data Base Management Systems
ID X,Y ID ATTRIB
1 1 1
2 2
2 3 3
3
CAD System Data Base Management System

5. Geographical Information System
Digital
Mapping
Computer
Photo-
Aided
grammetry
Design
GIS
Databases Surveying
Remote
Sensing
Cross-disciplinary nature of GIS

6. Geographical Information System
components
Spatial
data
GIS
Computer hardware /
?
Specific applications /
software tools decision making objectives

7. What makes data spatial?
Grid co-ordinate Placename
Latitude / Longitude
Postcode
Description
Distance & bearing

8. Characteristics of spatial data
• Location
• Description: Kingston
University,PenrhynRoad Centre
• Post Code: KT1 2EE
• Grid Reference: 518106.72 168530.37
• Latitude/Longitude: 0° 21’ 55.38”W, 49° 36’ 17.62”N

9. System Process Flow
•Input & update spatial information
• Data conversion
• Storage & management of
information
• Manipulation of spatial data
• Analysis of spatial information
• Presentation of data

10. GIS Structure
Data Input
Geographic
Query Database
Transformation
Output: Display
and Analysis

11. Co-Ordinate System
• A co-ordinate system is a standardized method
for assigning codes to locations so that
locations can be found using the codes alone.

15. Other GIS Features

17. Field View
Real world is continuous
– Infinite number of places exist
– Coordinate system may be used to define
locations
– Geographical variation may be described by
variables (or attributes)
⇒Population density
⇒ Elevation
⇒Temperature
• Attribute may be conceptualized as a field
– Each field represents the variation of
attribute over the surface of the earth

18. Field View
Referencing the Field
{a, x, y, z, t}
a = attribute (empirically confirmable)(tag)
x,y,z = spatial coordinates
t = reference to time

19. Database Management System

20. DBMS Components
• Data model
• Data input
• Indexing – data structure
• Query language
• Security (controlled access)
• Controlled update
• Backup and recovery
• Standard operations, data manipulation,
administrative tools
• Programmable interface - customization

21. DBMS Types
• Tabular (flat file)
• Hierarchical
• Network
• Relational
• Object
• Object-relational
• Deductive

22. GIS Based Functionality
• Layers of information – data integration
• Visual inspection
• Query
• Buffering – regular and irregular
• Overlay
• Areal interpolation

24. GIS is a part of Decision
Making process

25. Other GIS Features
• Produce good cartographic products
(translation = maps)
• Generate and maintain metadata
• Use and share geo-processing models
• Managing data in a geodatabase
using data models for each sector

26. Databases & GIS
Spatial
data
• At a simple
level a GIS
may just form
the graphical
interface to a
database
• The majority
of GIS
applications
MapI
Linked database SQL Query
follow this
nfo
table Manager example

27. Buffering
• Creation of an area of interest around an object
– proximity analysis and environmental impact assessmen

28. GIS Provide Data Integration
Example:
- Roads
- Population
- Hospitals
- Wells
- Mines

29. Spatial Image
• Information referenced by its
location in space

30. Data Representation
Raster Image
Vector Image
Real World

31. Spatial data storage
7,10
5,9
10
Vector model •
9,8
4,7
polygon as geometric
1,6 8,6
5 2,5
6,6 objects:
li ne 5,4 points, lines,
point
2,2 4,1
polygons
5 10
as image files
composed of
Raster model • grid-cells
(pixels)
A Desktop GIS should be able to handle both
types of data effectively!

32. The benefits of GIS include:
• Better information management
• Higher quality analysis
• Ability to carry out “what if?” scenarios
• Improve project efficiency
32

33. GIS Softwares
• ArcGIS
• ArcView
• AutoCAD MAP
• UNIX GIS
• GRASS

34. Arc GIS

35. Arc GIS
http://www.esri.com/flashmedia/arcview06.swf

36. Thanks for your time