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SESSION 2011-12A

PRACTICAL TRAINING SEMINAR ON

BASICS OF REMOTE SENSING & GIS

PRESENTED BY:

PAWAN TAK

IV YEAR / 7th SEMESTER,Branch- ECE

SRSACState Remote Sensing Application Center(Department of Science and Technology (Govt. of Rajasthan).)

• In Rajasthan , Remote Sensing Activities started with the establishment of  "Aerial Photo Interpretation Laboratory (APIL)" at Jodhpur in 1979.

• In 1985 State Department of science and Technology and renamed as “State Remote Sensing Application Centre (SRSAC).”

Objectives of SRSAC:

• Aerial Photo Interpretation and Satellite data interpretation both visually as well as digital mode.

• To generate information system on natural resources.

• To interact with various user agencies for the formulation and implementation of Remote Sensing Projects for development planning.

• To interact with National Remote sensing Institute like National Remote Sensing agency (NRSA), Hyderabad, Space Application Centre (SAC), Ahmadabad, Regional Remote Sensing Service Centre (RRSSC), Jodhpur to carry out joint projects.

Overview:1.Remote Sensing2. G.I.S3. G.P.S

1.REMOTE SENSING:

“Remote sensing is an art or science by which information about an object can be gathered from a distance without being in physical contact with it .’’

REMOTE SENSING

SATELITE SENSING

Nasa earth observatories

SENSORS:

1.ACTIVE SENSORS,2.PASSIVE SENSORS.

Working of remote sensing

2.GIS SYSTEM:2.1 Air Borne2.2 Space Borne2.3 Ground Borne

LEVELS OF GIS SYSTEM

2.1 AIR BORNE

AIR BORNE

AIR BORNE IMAGE

2.1 AIR BORNE:In this art of science, photographs are taken by a camera on an airplane. Scale of photograph , S = F/ HWhere ,F=focal length of lensH=height of aircraftFor various levels of study different scales of photographs are used.Taking photographs is initial step of PHOTOGRAMMETRY.

Photogrammetry is the science of making measurements from photographs.

• The output of Photogrammetry is typically a map, drawing or a 3d model of some real-world object or scene.

• Many of the maps we use today are created with Photogrammetric and photographs taken from aircraft.

Mirror Stereoscope• Use to view the Photogrammetry photographs.

2.2 SPACE BORNE

2.2 SPACE BORNE

SPACE BORNE:

• In this type of remote sensing object is sensed from space by a satellite through various types of sensors .

• It is concerned with the measurement of sun’s energy (electromagnetic) which are reflected, emitted by objects receiving and returning the energy from the sun.

1.Geostationary Satellite

2.Polar Orbital Satellite

3.Navigation satellites:

These were developed primarily to satisfy the need navigation system that nuclear submarines could use to update their inertial navigation system.

The Navigation Satellite for Time and Ranging/Global Positioning Satellite System (Navstar/GPS) consists of 24 satellites approximately 11,000 miles above the surface of the earth in six different orbital planes.

4.Reconnaissance satellite:

It artificial satellite launched by a country to provide intelligence information on the military activities of foreign countries.

2.3 GROUND BORNE

GROUND BORNE:

• In this type of remote sensing observation of each and every object is done via going to that place directly and analyzing its features.

• Toposheets are prepared by Survey of India (SOI) through ground survey of a particular location.

• A toposheet is a shortened name for 'Topographic sheet'. They essentially contain information about an area like roads, railways, settlements, canals, rivers, electric poles, post offices etc.

TOPO SHEET

TOPO SHEET

GEOGRAPHIC INFORMATION SYSTEM (GIS)“An organized collection of computer hardware, software, geographic data, and personnel designed to efficiently capture, store, update, manipulate, analyze, and display all forms of geographically referenced information. "

Data representation:

• Real world objects can be divided into two abstractions: discrete objects (a house) and continuous fields (rain fall amount or elevation).

• There are two broad methods used to store data in a GIS for both abstractions: Raster and Vector.

1.Raster GIS Packages

2.Vector GIS Packages

Raster Images:

A raster image is a collection of dots called pixels. Each pixel is a tiny colored square. When an image is scanned, the image is converted to a collection of pixels called a raster image. Scanned graphics and web graphics (JPEG and GIF files) are the most common forms of raster images.

Vector Images:A vector image is a collection of connected lines and curves that produce objects. When creating a vector image in a vector illustration program, node or drawing points are inserted and lines and curves connect dotes together. This is the same principle as "connect the dots". Each node, line and curve is defined in the drawing by the graphics software by a mathematical description.

Note: Vector images are object-oriented while raster images are pixel oriented.

RASTER IMAGE

• wells, lines for rivers, and a polygon for the lake.

VECTOR IMAGE

3.GPS(GLOBAL POSITIONING SYSTEM)

GLOBAL POSITIONING SYSTEM(GPS)

The Global Positioning System (GPS) is a satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of Defense.

Points:

• No. of satellite = 24• Height= 20,500Kms• Software Used= Terra sync• Minimum receivers required= 2 to 3• Range= 30 to 40 Kms

GPS SYSTEM IS:

GPS System is a worldwide navigation system formed from a constellation of 24 satellites and the associated ground stations. There can be more than 24 operational satellites; new ones are launched periodically to replace older satellites. There are some GPS system as:automobile navigation, marine navigation, outdoors,

outdoor handheld gps

automobile gps sys. marine-gps-system

NETWORK OF 24 SATELLITES

….Thank you ….