Geographic Information System for Egyptian Railway System(GIS)

Geographic Information System (GIS)Eng. Ismail El Gayar

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

Geographical Information System Modules

• Database• Map information• Computer-based link between them

This technology has developed from:– Digital cartography and CAD– Data Base Management Systems

Geographical Information System

1

2

3

ATTRIBID X,Y123

ID123

CAD System Data Base Management System

Geographical Information System

DigitalMapping

Photo-grammetry

ComputerAided

Design

Surveying

RemoteSensing

Databases

GIS

Cross-disciplinary nature of GIS

Geographical Information Systemcomponents

Specific applications /

decision making objectives

?G I S

Spatial

data

Computer hardware /

software tools

What makes data spatial?

PlacenameGrid co-ordinate

Postcode

Distance & bearingDescription

Latitude / Longitude

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

• Input & update spatial information

• Data conversion

• Storage & management of information

• Manipulation of spatial data

• Analysis of spatial information

• Presentation of data

System Process Flow

GIS Structure

GeographicDatabase

Data Input

Transformationand Analysis

Query

Output: Display

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.

Other GIS Features

Real world is continuous– Infinite number of places exist– Coordinate system may be used to definelocations– Geographical variation may be described byvariables (or attributes)⇒Population density

⇒ Elevation⇒Temperature• Attribute may be conceptualized as a field– Each field represents the variation ofattribute over the surface of the earth

Field View

Referencing the Field{a, x, y, z, t}

a = attribute (empirically confirmable)(tag)

x,y,z = spatial coordinates

t = reference to time

Field View

Database Management System

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

DBMS Types

• Tabular (flat file)• Hierarchical• Network• Relational• Object• Object-relational• Deductive

GIS Based Functionality

• Layers of information – data integration• Visual inspection• Query• Buffering – regular and irregular• Overlay• Areal interpolation

GIS is a part of Decision Making process

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

Databases & GIS

• At a simple level a GIS may just form the graphical interface to a database

• The majority of GIS applications follow this example

Linked database table

Spatial data

SQL Query Manager

MapInfo

Buffering

• Creation of an area of interest around an object– proximity analysis and environmental impact assessment.

GIS Provide Data Integration

Example:- Roads- Population- Hospitals- Wells- Mines

Spatial Image

• Information referenced by its location in space

Data Representation

Raster Image

Vector Image

Real World

Spatial data storage

•Vector model

•Raster model

point

1,6

2,5

5,4

4,1

7,105,9

4,7

6,68,6

9,8

line

polygon

2,2

5 10

5

10

as geometric objects: points, lines, polygons

as image files composed of grid-cells (pixels)

A Desktop GIS should be able to handle bothtypes of data effectively!

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The benefits of GIS include:

• Better information management

• Higher quality analysis

• Ability to carry out “what if?” scenarios

• Improve project efficiency

GIS Softwares

• ArcGIS• ArcView• AutoCAD MAP• UNIX GIS• GRASS

Arc GIS

Arc GIS

http://www.esri.com/flashmedia/arcview06.swf

Thanks for your time