this ppt for understand basic gis and remote sensing.

1. Geographical information
system
A.D.I.T
PREPARED BY:DHIREN P PATEL
5TH SEM MECH.ENGG.
(120013119002)

2. REMOTE SENSING SYSTEM

3. Remote sensing
system
• The gathering of information from an object or surface
without direct contact.

4. History
• 1858 Balloonist G.Tournachon made photographs of
Paris from his balloon.
• Systematic aerial photography developed for military and
reconnaissance purposes beginning in World War I and
reaching a climax during the Cold War .
• Artificial satellites in the latter half of the 20th century.

5. Types
• Passive Remote Sensing
• Photography
• Radiometers
• Infrared
• Active Remote Sensing
• RADAR
• LiDAR

6. Applications
• Forestry
• Agriculture
• Hydrology
• Sea Ice
• Land Cover & Land Use

7. Techniques
 Spectral Signatures
 Image Acquisition
 Spatial Resolution
 Spectral Resolution
 Multispectral Images
 Radiometric Resolution

8. High Resolutions
Low Resolution
Multi Spectral
Hyper Spectral:

9. System Used
• Optical System
•
•
•
•
Panchromatic imaging system
Multispectral imaging system
Super spectral Imaging System
Hyper spectral Imaging System
• RADAR System
• LiDAR System

10. Optical Remote System
• Optical remote sensing makes use of visible, near
infrared and short-wave infrared sensors to form images
of the earth's surface by detecting the solar radiation
reflected from targets on the ground.

11. Panchromatic Imaging System
• A single channel sensor is used to detect radiation
• If range of wavelength and the visible range become
same then the imagery will appear as a black and white
photograph taken from space

12. Multispectral Imaging System
• Uses a multi channel detector and records
radiation with a narrow range
• Brightness and color informatics are
available

13. Super Spectral Imaging System
• Finer spectral feature that capture by the
sensors.

14. PHOTOGRAMMETRY
an introduction…

15. Photogrammetry is the technique of measuring objects (2D
or 3D) from photographs
Its most important feature is the fact, that the
objects are measured without being touched.

16. Photogrammetry
• objects are measured WITHOUT TOUCHING.
• It is a REMOTESENSING technique.
• It is a close range method of measuring objects.
• It is a 3-dimensional coordinate measuring technique that uses
PHOTORAPHS as the fundamental medium for measurement.

17. Principle
• The main principle is “TRIANGULATION”.
• Eyes use the principle of TRIANGULATION to gauge distance
(depth perception).
• TRIAGULATION is also the principle used by theodolites for
coordinate measurement.

18. Triangulation
By taking photographs from at least two different
locations, so-called "lines of sight" can be developed from each
camera to points on the object. These lines of sight (sometimes
called rays owing to their optical nature) are mathematically
intersected to produce the 3-dimensional coordinates of the
points of interest.

19. Introduction To Surveying
• Definition:
Surveying is the science and art of determining
the relative positions of points above, on, or
beneath the earth’s surface and locating the
points in the field.

20. The Work Of The Surveyor
Consists Of 5 Phases:
1. Decision Making – selecting method, equipment and
final point locations.
2. Fieldwork & Data Collection – making measurements
and recording data in the field.
3. Computing & Data Processing – preparing
calculations based upon the recorded data to
determine locations in a useable form.
4. Mapping or Data Representation – plotting data to
produce a map, plat, or chart in the proper form.
5. Stakeout – locating and establishing monuments or
stakes in the proper locations in the field.

21. 2 Categories of Surveying:
1. Plane Surveying – surveying with the reference base
for fieldwork and computations are assumed to be a
flat horizontal surface.
–
Generally within a 12 mile radius the pull of gravity is very
nearly parallel to that at any other point within the radius
and thus horizontal lines can be considered straight.
2. Geodetic Surveying – surveying technique to
determine relative positions of widely spaced points,
lengths, and directions which require the
consideration of the size and shape of the earth.
(Takes the earth’s curvature into account.)

22. 7 Types of Surveys:
1. Photogrammetry – mapping utilizing data obtained
by camera or other sensors carried in airplanes or
satellites.
2. Boundary Surveying – establishing property corners,
boundaries, and areas of land parcels.
3. Control Surveying – establish a network of horizontal
and vertical monuments that serve as a reference
framework for other survey projects.
4. Engineering Surveying – providing points and
elevations for the building Civil Engineering projects.

23. 7 Types of Surveys:
5. Topographic Surveying – collecting data and
preparing maps showing the locations of natural
man-made features and elevations of points o the
ground for multiple uses.
6. Route Surveys – topographic and other surveys for
long – narrow projects associated with Civil
Engineering projects.
– Highways, railroads, pipelines, and transmission
lines.
7. Hydrographic Surveying – mapping of shorelines
and the bottom of bodies of water.
– Also known as bathymetric surveying.

24. Geographic Information Systems (GIS)
• GIS are computer programs that allow users to store,
retrieve, manipulate, analyze and display spatial data
• Spatial Data (Geographic data) – any data that
represents information about the Earth
GIS components
– Recent definitions of GIS suggest that is consists of:
1. Hardware (computer and operating system)
Geographic/Spatial
2. Software
3. Data
Non-Geographic/Aspatial/Attribute
4. Human Operators and Institutional Infrastructure

25. GIS Data Structures
• Vector – Made up of points, lines, and polygons

26. GIS Data Structures
• Raster (Grids) – Made up of pixels of computer screen

27. GIS Data Structures
• DEM (Digital Elevation Model) – Digital terrain
representation technique, where elevation values are
stored in raster cells

28. Future of Surveying
• Major advances in future
– Remote Sensing (Government and Military)
– Arial Photographs
• Design Professions
– Every 10 years, must justify to Legislature that need for our
license exists
– Surveyor have ULTIMATE liability
– Standards → Laws
– Continuing Education – Enough points every 2 years

29. REFERENCES
• www.howstuffworks.com
• www.remotesearch.in
• http://www.tutavivito.com