SlideShare ist ein Scribd-Unternehmen logo
Tracking and Data Relay Satellite System (TDRSS)
Analog image
Images with continuous gray tone or color like a photograph
is called analog image
Digital image is the numerical record of the radiance leaving
each of the pixel in each of the spectral bands
Rayleigh Scattering: dominant scattering mechanism in the upper
atmosphere ( 9-10 km), also called clear atmosphere scattering
Mie scattering:Occurs when the particles are just about the same size as the
wavelength of the radiation (Dust, pollen, smoke and water
vapour), occurs in lower atmosphere. (0 – 5 KM)
By measuring the energy that is reflected (or emitted) by targets
on the Earth's surface over a variety of different wavelengths,
we can build up a spectral response for that object, termed a
spectral reflectance curve.
Specular Reflection: angle of incidence is same as angle of reflection
Diffused Reflection: angle of incidence is different from angle of reflection
The spatial property defines the dimensions of the
corresponding ground area.
The spectral property defines the intensity of the
spectral response for a pixel in a particular band
Spatial resolution refers to the size of the smallest possible
feature that can be detected by the sensor.
Spectral resolution describes the wavelength intervals
in the electromagnetic spectrum that a sensor can
record or sense
The ability of an imaging system to record many levels of
Brightness is Radiometric Resolution.
Geography - Pattern and process of human and
physical phenomena on the surface of earth.
URISA Urban and Regional Information Systems Association
DIME Dual Independent Map Encoding
TIGER Topologically Integrated Geographic Encoding And Referencing
CAD: Computer Assisting Drawing, e.g. AutoCad, Micro station
GDS: Graphic Design System, e.g. CorelDraw, Illustrator
DBMS: Database Management System, e.g. Oracle, Sybase
DIPS: Digital Image Processing System, e.g. PCI, Erdas
GPS: Global Positioning Systems, e.g. Garmin, Trimble
�Using the tools and helping to build the tools of
geographic information systems (GISystems)
�Studying the theory and concepts that lie behind GIS and
other geographic information technologies (GIScience)
�Study the societal context of geographic information –
legal context, issues of privacy, economics of geographic
information (GIStudies)
ESRI: Environmental Systems Research Institue
Arcinfo uses Arc Macro Language (AML)
ArcView uses Visual Basic and Python
ArcGIS comes in three different versions based on the capabilities
provided by the software: ArcView, ArcEditor and ArcInfo.
Gis data types:
 Feature data
 Image data
 Grid data
 Attribute data
A data model is a :
 Logical Construct for representing real world phenomenon and objects in a
computer
Coverages and shapefiles are examples of the Georelational
Data Model
Geodatabases are examples of the Object‐Based Data
Model.
The Georelational Data Model stores spatial and attribute data
separately in a split system
Spatial data in ‘graphic files’
Attribute data in ‘relational database files’.
The link between the two ‘systems’ is usually a “Feature Label”
or ID
Object‐based data model stores spatial and attribute data of
spatial features in a single system. Spatial data are stored in a
field using a data type called “BLOB” (binary large object)
Topology is the science and mathematics which defines the spatial or
geometrical relationship between spatial features or vector objects in a GIS.
Topology is the study of those properties of geometric objects that remain
invariant under certain transformations such as bending or stretching.
Adjacency and Incidence are two relationships that can be established
between nodes and arc in digraphs. If a line joins two points, the points are said
to be adjacent and incident with the line.
Topological properties:-
Connectivity, Contiguity/Adjacency, Direction ,Containment
Topological data model makes spatial analysis feasible, automatic corrections
in plottings, faster processing of larger datasets. But it is expensive and time
consuming. Updating topology becomes necessary once spatial data is
updated. Complex data form making it difficult for developers to interpret.
Spaghetti Data model is the simplest and direct vector representation of a real
world object. Easy to produce, display and understand but no spatial analysis
possible.
TIGER- census data linked to boundary data of counties, block groups etc.
ESRI Coverage model:-
Point coverage: node ID + coordinates
Line coverage: arc IDs + S and E node, arc ID + coordinates.
Polygon coverage: arc IDs + L and R polygon, polygon + arc IDs, arc IDs +
coordinates
DIME:- Arc IDs + S and E node + L and R polygon, Coordinate file for nodes
Composite features refer to those spatial features that are better represented as
composites of points, lines, and polygons.
TINS: Triangulated Irregular Networks
Formed by using Delaunay Triangulation which is an iterative process of
connecting points with their two nearest neighbors to form triangles.
Raster data model:-
Storage increases with the square of the resolution.
Elements:
1. Cell value. Each cell in a raster carries a value, which represents the
characteristic of a spatial phenomenon at the location denoted by its row and
column. The cell value can be integer or floating-point.
2. Cell size. The cell size determines the resolution of the raster data model.
3. Raster bands. A raster may have a single band or multiple bands.
4. Spatial reference. Raster data must have the spatial reference information so
that they can align spatially with other data sets in a GIS.
Attribute data is stored logically in flat files.
Cell by cell: row n: 0110
Run length encoding: 23
Quad tree or hierarchical encoding
DOQ is a image prepared from an aerial photograph or other remotely sensed
data, in which the displacement caused by camera tilt and terrain relief has
been removed.
DEM is a digital representation of a topographic surface. It is mutli-faceted.
Data sources:
Data capture: Surveys,RS,Digitization
Data inputs/ sources: Maps, orthophotos, statistical reports, Satellite Imagery,GPS
Input is :
- Time consuming
- Labour intensive and error prone
- Accuracy of GIS analysis rests on accuracy of input data
- Expensive
Selection of input data: depends on price, availability, spatial analysis required,
scale, format, available skills and hardware and software
• Federal Geographic Data Committee (FGDC)
• Geospatial One‐Stop (GOS)
• US Geological Survey (USGS)
Metadata describes the characteristics, development and origin of the spatial
data.
FGDC
- Identification Information (Title, geographic data covered)
- Data Quality Information (positional, attribute, completeness, sources of
information, methods to produce spatial data)
- Spatial Data Organization Information (Raster or Vector)
- Spatial Reference Information (Datum, Projections, Coord Sys)
- Distribution Information (Information about obtaining dataset)
- Metadata Reference Information (currency of the metadata and
responsible party)
Geodesy, is the scientific discipline that deals with the measurement and
representation of the earth, its gravitational field, and other geodynamic
phenomena, such as crustal motion, oceanic tides, and polar motion.
Coordinate systems:
PCS (Flat, inches feet metres), GCS( curved , Degrees minutes seconds).
60 N 45 E
Conversion of polar to Cartesian:
Transformation is the projection of a digitized map or image, in some cases from
its original coordinate system, onto a new coordinate system.
Two main types :- map to map and image to map.
4 methods: Affine( angular distortions but parallelism preserved, similarity shape
preserved not size, equiarea (area and shape preserved), projective( angular
and shape distortions).
Affine transformation allows: skew, rotation, differential scaling and translation
Affine used for above mentioned trans. , aerial photos need projective trans.
And satellite imagery needs polynomial or warping trans.
A geometric transformation typically involves three steps.
•Step 1 updates the control points to real-world coordinates.
•Step 2 uses the control points to run an affine transformation.
•Step 3 creates the output by applying the transformation equations to the input
features.
A quantitative measure of the displacement (the deviation) between the actual
(true) and estimated (digitized) locations of the control points is RMS.
Resampling in this case means filling each pixel of the new image with a value
or a derived value from the original image.
– Nearest neighbor: fills each pixel of the new image with the nearest pixel value
from the original image
– Bilinear interpolation: uses the average of the four nearest pixel values from
three linear interpolations
– Cubic convolution: uses the average of the 16 nearest pixel values from five
cubic polynomial interpolations
Map algebra is a language specifically designed for
geographic cell‐based systems and provides the
basis for cartographic modeling. Uses mathematical expressions to create new
grid themes.
Arithmetic operators, relational operators, Boolean operators, Functions (trig,log)
Raster functions (Output grid generated using input grid as argument): Zonal
(cells chosen), local (more than one or one argument), global and focal (cells
immediate neighbours only).
Uses: Surface generation and analysis (hillshade, viewshed), Data
reclassification, Transformations, Distance Analysis (shortest path, cost
weighted).
Buffer made. Layer of important features created, all queries applied and select
by attributes for final results.
Statistical local function
Overlay functions: union , intersect , identity
No data in cell no data in output ( set condition otherwise default value is -9999)
Raster data model Vector data model
Advantages
Can store photos Processing of large data sets is easier
once topological relations between
features are established
Simple data structure Prints are aesthetically pleasing
Easier Spatial analysis especially
overlay (Grid based coincidence)
-
Can accurately represent continuous
phenomena
Can accurately represent discrete
features
Disadvantages
Prints appear blocky Cannot store photos
Processing of large datasets is time
consuming
Cannot represent continuous spatial
variability accurately
Quality and productivity largely
depends on resolution
Spatial Analysis is time consuming
without a developed topology
- Complex data structure
Photo vs remote
Quantitative and qualitative
Geometry vs radiometry
Visible vs invisible
Small area coverage vs large area coverage
Uses metadata:
Identification of source, techniques of obtaining/ Projection and coordinate systems/
scale/cost/availability
Organization of spatial data/ developmental history
Data sharing possible
Data interpretation techniques
Uses GIS: Monitoring weather, disaster management, traffic management, urban and regional
planning, Crop yields, Effects of different phenomena on environment.
Uses Spatial analysis: Identifying developmental patterns, trends , making predictions,
modeling, monitoring changes in environments and their effects.
Digitizing adva. And disadva.:-
Automatic error detection vs error prone
Enabling spatial analysis and easier interpretation vs Slow process
Transformation possible vs need of digitizing equipment
UTM: 84 n to 80 S, 60 zones (6 deg. Each) East –west, Transverse Mercator projection, Alphabet
zones 20 north-south. Cartesian system.
Clipping, dicing
Mosiacing, raster bands
AOI, Inquire box, Coordinates
Annotations, dynamic labels
Graduated color , graduated symbol, dot density, proportional symbol
Discrete color, unique color, classified,
Natural breaks is the default method. Developed by the cartographer
George Jenks, it creates
classes according to clusters and gaps in the data.
Equal interval creates classes of equal va lue ranges. If the range of
values is 1 to 100 and the
number of classes is 4, this method will create classes from 1-25,26-
50,51-75, and 76-100.
Defined interval resembles equal interval except that the interval
determines the number of
classes rather than the other way around. If the range of values is 1 (Q
100, and you choose
an interval of 10, this method will create 10 classes: 1- 10, 11-20, 21-30,
and so on.
Quantile creates classes containing equal numbers of features. If you
choose five classes for a
layer with 100 features, this method will create class breaks so that 20
features fall into each
class. The value range varies from class to class.
Standard deviation creates classes according (Q a specified number of
standard deviations
from the mean value.
Geometric intervals creates classes based on class intervals that have a
geometric series. A
geometric series is a pattern where a constant coefficient multiplies each
value in the series. It
produces a result that is visually appealing, cartographically
comprehensive, and minimizes
variance within classes.

Weitere ähnliche Inhalte

Was ist angesagt?

Surface Representations using GIS AND Topographical Mapping
Surface Representations using GIS AND Topographical MappingSurface Representations using GIS AND Topographical Mapping
Surface Representations using GIS AND Topographical Mapping
NAXA-Developers
 
Gis Tutorial Purnawan
Gis Tutorial PurnawanGis Tutorial Purnawan
Gis Tutorial Purnawan
Kodok Ngorex
 

Was ist angesagt? (20)

Surface Representations using GIS AND Topographical Mapping
Surface Representations using GIS AND Topographical MappingSurface Representations using GIS AND Topographical Mapping
Surface Representations using GIS AND Topographical Mapping
 
Four data models in GIS
Four data models in GISFour data models in GIS
Four data models in GIS
 
Digital elevation model in GIS
Digital elevation model in GISDigital elevation model in GIS
Digital elevation model in GIS
 
Understanding raster
Understanding rasterUnderstanding raster
Understanding raster
 
Raster data model
Raster data modelRaster data model
Raster data model
 
Spatial data for GIS
Spatial data for GISSpatial data for GIS
Spatial data for GIS
 
Vector data model
Vector data model Vector data model
Vector data model
 
TYBSC IT PGIS Unit I Chapter I- Introduction to Geographic Information Systems
TYBSC IT PGIS Unit I  Chapter I- Introduction to Geographic Information SystemsTYBSC IT PGIS Unit I  Chapter I- Introduction to Geographic Information Systems
TYBSC IT PGIS Unit I Chapter I- Introduction to Geographic Information Systems
 
datamodel_vector
datamodel_vectordatamodel_vector
datamodel_vector
 
Remote sensing
Remote sensingRemote sensing
Remote sensing
 
Gis Concepts 1/5
Gis Concepts 1/5Gis Concepts 1/5
Gis Concepts 1/5
 
Raster data analysis
Raster data analysisRaster data analysis
Raster data analysis
 
Data models in geographical information system(GIS)
Data models in geographical information system(GIS)Data models in geographical information system(GIS)
Data models in geographical information system(GIS)
 
Geographic query and analysis
Geographic query and analysisGeographic query and analysis
Geographic query and analysis
 
Digital terrain representations(last)
Digital terrain representations(last)Digital terrain representations(last)
Digital terrain representations(last)
 
TYBSC IT PGIS Unit IV Spacial Data Analysis
TYBSC IT PGIS Unit IV  Spacial Data AnalysisTYBSC IT PGIS Unit IV  Spacial Data Analysis
TYBSC IT PGIS Unit IV Spacial Data Analysis
 
Surfer software
Surfer softwareSurfer software
Surfer software
 
Gis Tutorial Purnawan
Gis Tutorial PurnawanGis Tutorial Purnawan
Gis Tutorial Purnawan
 
Georeferencing
GeoreferencingGeoreferencing
Georeferencing
 
Lect 7 & 8 types of vector data model-gis
Lect 7 & 8 types of vector data model-gisLect 7 & 8 types of vector data model-gis
Lect 7 & 8 types of vector data model-gis
 

Andere mochten auch (7)

Cpr for dummies
Cpr for dummiesCpr for dummies
Cpr for dummies
 
Public Health Engineering - Concepts Regarding Water
Public Health Engineering - Concepts Regarding WaterPublic Health Engineering - Concepts Regarding Water
Public Health Engineering - Concepts Regarding Water
 
Google search
Google search Google search
Google search
 
S-curve analysis for development of hydrographs
S-curve analysis for development of hydrographsS-curve analysis for development of hydrographs
S-curve analysis for development of hydrographs
 
Brief Introduction to Project Management
Brief Introduction to Project ManagementBrief Introduction to Project Management
Brief Introduction to Project Management
 
Selected verses from the quran
Selected verses from the quranSelected verses from the quran
Selected verses from the quran
 
International spheroid[1]
International spheroid[1]International spheroid[1]
International spheroid[1]
 

Ähnlich wie Scattered gis handbook

Terminology and Basic Questions About GIS
Terminology and Basic Questions About GISTerminology and Basic Questions About GIS
Terminology and Basic Questions About GIS
Mrinmoy Majumder
 
Introduction to GIS
Introduction to GISIntroduction to GIS
Introduction to GIS
Uday kumar Devalla
 
Introduction to GIS systems
Introduction to GIS systemsIntroduction to GIS systems
Introduction to GIS systems
Vivek Srivastava
 
Assignment vector raster
Assignment vector rasterAssignment vector raster
Assignment vector raster
fredsk2006
 

Ähnlich wie Scattered gis handbook (20)

Terminology and Basic Questions About GIS
Terminology and Basic Questions About GISTerminology and Basic Questions About GIS
Terminology and Basic Questions About GIS
 
Geographic Information System unit 1
Geographic Information System   unit 1Geographic Information System   unit 1
Geographic Information System unit 1
 
Fundamentals of GIS
Fundamentals of GISFundamentals of GIS
Fundamentals of GIS
 
the title of this course is Entitles as GIS and Remote sensing
the title of this course is Entitles as GIS and Remote sensingthe title of this course is Entitles as GIS and Remote sensing
the title of this course is Entitles as GIS and Remote sensing
 
spatial databases ADBMS ppt
spatial databases ADBMS pptspatial databases ADBMS ppt
spatial databases ADBMS ppt
 
UG6thSem_major_GIS Data Structures.pptx DR P DAS.1.pptx
UG6thSem_major_GIS Data Structures.pptx DR P DAS.1.pptxUG6thSem_major_GIS Data Structures.pptx DR P DAS.1.pptx
UG6thSem_major_GIS Data Structures.pptx DR P DAS.1.pptx
 
Geographic information system (gis)
Geographic information system (gis)Geographic information system (gis)
Geographic information system (gis)
 
THE NATURE AND SOURCE OF GEOGRAPHIC DATA
THE NATURE AND SOURCE OF GEOGRAPHIC DATATHE NATURE AND SOURCE OF GEOGRAPHIC DATA
THE NATURE AND SOURCE OF GEOGRAPHIC DATA
 
Intro to GIS and Remote Sensing
Intro to GIS and Remote SensingIntro to GIS and Remote Sensing
Intro to GIS and Remote Sensing
 
Gis Concepts 2/5
Gis Concepts 2/5Gis Concepts 2/5
Gis Concepts 2/5
 
Introduction to GIS
Introduction to GISIntroduction to GIS
Introduction to GIS
 
Basic of gis concept and theories
Basic of gis concept and theoriesBasic of gis concept and theories
Basic of gis concept and theories
 
Geographic information system
Geographic information systemGeographic information system
Geographic information system
 
Introduction to GIS systems
Introduction to GIS systemsIntroduction to GIS systems
Introduction to GIS systems
 
Fundamentals of GIS and Database Management for Disaster Management
Fundamentals of GIS and Database Management for Disaster ManagementFundamentals of GIS and Database Management for Disaster Management
Fundamentals of GIS and Database Management for Disaster Management
 
Assignment vector raster
Assignment vector rasterAssignment vector raster
Assignment vector raster
 
Introduction and Application of GIS
Introduction and Application of GISIntroduction and Application of GIS
Introduction and Application of GIS
 
3D Analyst
3D Analyst3D Analyst
3D Analyst
 
TerraWorld
TerraWorldTerraWorld
TerraWorld
 
Data collection
Data collectionData collection
Data collection
 

Mehr von Waleed Liaqat

Mehr von Waleed Liaqat (20)

The Three Step Writing Process (Technical & Business Writing)
The Three Step Writing Process (Technical & Business Writing)The Three Step Writing Process (Technical & Business Writing)
The Three Step Writing Process (Technical & Business Writing)
 
Nietzsche's Philosophies
Nietzsche's Philosophies Nietzsche's Philosophies
Nietzsche's Philosophies
 
Brief Introduction to Architecture
Brief Introduction to ArchitectureBrief Introduction to Architecture
Brief Introduction to Architecture
 
Urban Planning Types, Processes and History
Urban Planning Types, Processes and HistoryUrban Planning Types, Processes and History
Urban Planning Types, Processes and History
 
Construction machinery - Associated costs and basic concepts
Construction machinery - Associated costs and basic conceptsConstruction machinery - Associated costs and basic concepts
Construction machinery - Associated costs and basic concepts
 
Fundamentals of Effective Business Communication
Fundamentals of Effective Business CommunicationFundamentals of Effective Business Communication
Fundamentals of Effective Business Communication
 
Introduction to town and Urban planning
Introduction to town and Urban planningIntroduction to town and Urban planning
Introduction to town and Urban planning
 
Brief Introduction to Project Life Cycle And Organizational Structures
Brief Introduction to Project Life Cycle And Organizational StructuresBrief Introduction to Project Life Cycle And Organizational Structures
Brief Introduction to Project Life Cycle And Organizational Structures
 
Resource Levelling - PMBOK - Example
Resource Levelling - PMBOK - ExampleResource Levelling - PMBOK - Example
Resource Levelling - PMBOK - Example
 
Youth and Education in Pakistan
Youth and Education in PakistanYouth and Education in Pakistan
Youth and Education in Pakistan
 
LEED 2009 applied to a mixed - use building
LEED 2009 applied to a mixed - use buildingLEED 2009 applied to a mixed - use building
LEED 2009 applied to a mixed - use building
 
An Overview of the History of Pakistan: 1947 - 1973
An Overview of the History of Pakistan: 1947 - 1973 An Overview of the History of Pakistan: 1947 - 1973
An Overview of the History of Pakistan: 1947 - 1973
 
Richter scale and mercalli scale
Richter scale and mercalli scaleRichter scale and mercalli scale
Richter scale and mercalli scale
 
Key Components of Cost Estimation in construction
Key Components of Cost Estimation in constructionKey Components of Cost Estimation in construction
Key Components of Cost Estimation in construction
 
Plain Concrete - General concepts
Plain Concrete - General conceptsPlain Concrete - General concepts
Plain Concrete - General concepts
 
Activity on Arrow Diagram
Activity on Arrow DiagramActivity on Arrow Diagram
Activity on Arrow Diagram
 
Remote sensing and it's applications
Remote sensing and it's applicationsRemote sensing and it's applications
Remote sensing and it's applications
 
What are standards
What are standardsWhat are standards
What are standards
 
Statistics is the science of collection
Statistics is the science of collectionStatistics is the science of collection
Statistics is the science of collection
 
Spillways
SpillwaysSpillways
Spillways
 

Kürzlich hochgeladen

Kürzlich hochgeladen (20)

NCERT Solutions Power Sharing Class 10 Notes pdf
NCERT Solutions Power Sharing Class 10 Notes pdfNCERT Solutions Power Sharing Class 10 Notes pdf
NCERT Solutions Power Sharing Class 10 Notes pdf
 
GIÁO ÁN DẠY THÊM (KẾ HOẠCH BÀI BUỔI 2) - TIẾNG ANH 8 GLOBAL SUCCESS (2 CỘT) N...
GIÁO ÁN DẠY THÊM (KẾ HOẠCH BÀI BUỔI 2) - TIẾNG ANH 8 GLOBAL SUCCESS (2 CỘT) N...GIÁO ÁN DẠY THÊM (KẾ HOẠCH BÀI BUỔI 2) - TIẾNG ANH 8 GLOBAL SUCCESS (2 CỘT) N...
GIÁO ÁN DẠY THÊM (KẾ HOẠCH BÀI BUỔI 2) - TIẾNG ANH 8 GLOBAL SUCCESS (2 CỘT) N...
 
Advances in production technology of Grapes.pdf
Advances in production technology of Grapes.pdfAdvances in production technology of Grapes.pdf
Advances in production technology of Grapes.pdf
 
Instructions for Submissions thorugh G- Classroom.pptx
Instructions for Submissions thorugh G- Classroom.pptxInstructions for Submissions thorugh G- Classroom.pptx
Instructions for Submissions thorugh G- Classroom.pptx
 
How to Create Map Views in the Odoo 17 ERP
How to Create Map Views in the Odoo 17 ERPHow to Create Map Views in the Odoo 17 ERP
How to Create Map Views in the Odoo 17 ERP
 
Basic Civil Engg Notes_Chapter-6_Environment Pollution & Engineering
Basic Civil Engg Notes_Chapter-6_Environment Pollution & EngineeringBasic Civil Engg Notes_Chapter-6_Environment Pollution & Engineering
Basic Civil Engg Notes_Chapter-6_Environment Pollution & Engineering
 
Sha'Carri Richardson Presentation 202345
Sha'Carri Richardson Presentation 202345Sha'Carri Richardson Presentation 202345
Sha'Carri Richardson Presentation 202345
 
Danh sách HSG Bộ môn cấp trường - Cấp THPT.pdf
Danh sách HSG Bộ môn cấp trường - Cấp THPT.pdfDanh sách HSG Bộ môn cấp trường - Cấp THPT.pdf
Danh sách HSG Bộ môn cấp trường - Cấp THPT.pdf
 
How to Manage Notification Preferences in the Odoo 17
How to Manage Notification Preferences in the Odoo 17How to Manage Notification Preferences in the Odoo 17
How to Manage Notification Preferences in the Odoo 17
 
Pragya Champions Chalice 2024 Prelims & Finals Q/A set, General Quiz
Pragya Champions Chalice 2024 Prelims & Finals Q/A set, General QuizPragya Champions Chalice 2024 Prelims & Finals Q/A set, General Quiz
Pragya Champions Chalice 2024 Prelims & Finals Q/A set, General Quiz
 
Application of Matrices in real life. Presentation on application of matrices
Application of Matrices in real life. Presentation on application of matricesApplication of Matrices in real life. Presentation on application of matrices
Application of Matrices in real life. Presentation on application of matrices
 
The impact of social media on mental health and well-being has been a topic o...
The impact of social media on mental health and well-being has been a topic o...The impact of social media on mental health and well-being has been a topic o...
The impact of social media on mental health and well-being has been a topic o...
 
Operations Management - Book1.p - Dr. Abdulfatah A. Salem
Operations Management - Book1.p  - Dr. Abdulfatah A. SalemOperations Management - Book1.p  - Dr. Abdulfatah A. Salem
Operations Management - Book1.p - Dr. Abdulfatah A. Salem
 
Morse OER Some Benefits and Challenges.pptx
Morse OER Some Benefits and Challenges.pptxMorse OER Some Benefits and Challenges.pptx
Morse OER Some Benefits and Challenges.pptx
 
50 ĐỀ LUYỆN THI IOE LỚP 9 - NĂM HỌC 2022-2023 (CÓ LINK HÌNH, FILE AUDIO VÀ ĐÁ...
50 ĐỀ LUYỆN THI IOE LỚP 9 - NĂM HỌC 2022-2023 (CÓ LINK HÌNH, FILE AUDIO VÀ ĐÁ...50 ĐỀ LUYỆN THI IOE LỚP 9 - NĂM HỌC 2022-2023 (CÓ LINK HÌNH, FILE AUDIO VÀ ĐÁ...
50 ĐỀ LUYỆN THI IOE LỚP 9 - NĂM HỌC 2022-2023 (CÓ LINK HÌNH, FILE AUDIO VÀ ĐÁ...
 
Sectors of the Indian Economy - Class 10 Study Notes pdf
Sectors of the Indian Economy - Class 10 Study Notes pdfSectors of the Indian Economy - Class 10 Study Notes pdf
Sectors of the Indian Economy - Class 10 Study Notes pdf
 
The Art Pastor's Guide to Sabbath | Steve Thomason
The Art Pastor's Guide to Sabbath | Steve ThomasonThe Art Pastor's Guide to Sabbath | Steve Thomason
The Art Pastor's Guide to Sabbath | Steve Thomason
 
Open Educational Resources Primer PowerPoint
Open Educational Resources Primer PowerPointOpen Educational Resources Primer PowerPoint
Open Educational Resources Primer PowerPoint
 
How to Split Bills in the Odoo 17 POS Module
How to Split Bills in the Odoo 17 POS ModuleHow to Split Bills in the Odoo 17 POS Module
How to Split Bills in the Odoo 17 POS Module
 
slides CapTechTalks Webinar May 2024 Alexander Perry.pptx
slides CapTechTalks Webinar May 2024 Alexander Perry.pptxslides CapTechTalks Webinar May 2024 Alexander Perry.pptx
slides CapTechTalks Webinar May 2024 Alexander Perry.pptx
 

Scattered gis handbook

  • 1. Tracking and Data Relay Satellite System (TDRSS) Analog image Images with continuous gray tone or color like a photograph is called analog image Digital image is the numerical record of the radiance leaving each of the pixel in each of the spectral bands Rayleigh Scattering: dominant scattering mechanism in the upper atmosphere ( 9-10 km), also called clear atmosphere scattering Mie scattering:Occurs when the particles are just about the same size as the wavelength of the radiation (Dust, pollen, smoke and water vapour), occurs in lower atmosphere. (0 – 5 KM) By measuring the energy that is reflected (or emitted) by targets on the Earth's surface over a variety of different wavelengths, we can build up a spectral response for that object, termed a spectral reflectance curve. Specular Reflection: angle of incidence is same as angle of reflection Diffused Reflection: angle of incidence is different from angle of reflection The spatial property defines the dimensions of the corresponding ground area. The spectral property defines the intensity of the spectral response for a pixel in a particular band Spatial resolution refers to the size of the smallest possible feature that can be detected by the sensor. Spectral resolution describes the wavelength intervals in the electromagnetic spectrum that a sensor can record or sense The ability of an imaging system to record many levels of Brightness is Radiometric Resolution. Geography - Pattern and process of human and physical phenomena on the surface of earth. URISA Urban and Regional Information Systems Association DIME Dual Independent Map Encoding TIGER Topologically Integrated Geographic Encoding And Referencing CAD: Computer Assisting Drawing, e.g. AutoCad, Micro station GDS: Graphic Design System, e.g. CorelDraw, Illustrator DBMS: Database Management System, e.g. Oracle, Sybase DIPS: Digital Image Processing System, e.g. PCI, Erdas GPS: Global Positioning Systems, e.g. Garmin, Trimble �Using the tools and helping to build the tools of geographic information systems (GISystems)
  • 2. �Studying the theory and concepts that lie behind GIS and other geographic information technologies (GIScience) �Study the societal context of geographic information – legal context, issues of privacy, economics of geographic information (GIStudies) ESRI: Environmental Systems Research Institue Arcinfo uses Arc Macro Language (AML) ArcView uses Visual Basic and Python ArcGIS comes in three different versions based on the capabilities provided by the software: ArcView, ArcEditor and ArcInfo. Gis data types:  Feature data  Image data  Grid data  Attribute data A data model is a :  Logical Construct for representing real world phenomenon and objects in a computer Coverages and shapefiles are examples of the Georelational Data Model Geodatabases are examples of the Object‐Based Data Model. The Georelational Data Model stores spatial and attribute data separately in a split system Spatial data in ‘graphic files’ Attribute data in ‘relational database files’. The link between the two ‘systems’ is usually a “Feature Label” or ID Object‐based data model stores spatial and attribute data of spatial features in a single system. Spatial data are stored in a field using a data type called “BLOB” (binary large object) Topology is the science and mathematics which defines the spatial or geometrical relationship between spatial features or vector objects in a GIS. Topology is the study of those properties of geometric objects that remain invariant under certain transformations such as bending or stretching. Adjacency and Incidence are two relationships that can be established between nodes and arc in digraphs. If a line joins two points, the points are said to be adjacent and incident with the line. Topological properties:-
  • 3. Connectivity, Contiguity/Adjacency, Direction ,Containment Topological data model makes spatial analysis feasible, automatic corrections in plottings, faster processing of larger datasets. But it is expensive and time consuming. Updating topology becomes necessary once spatial data is updated. Complex data form making it difficult for developers to interpret. Spaghetti Data model is the simplest and direct vector representation of a real world object. Easy to produce, display and understand but no spatial analysis possible. TIGER- census data linked to boundary data of counties, block groups etc. ESRI Coverage model:- Point coverage: node ID + coordinates Line coverage: arc IDs + S and E node, arc ID + coordinates. Polygon coverage: arc IDs + L and R polygon, polygon + arc IDs, arc IDs + coordinates DIME:- Arc IDs + S and E node + L and R polygon, Coordinate file for nodes Composite features refer to those spatial features that are better represented as composites of points, lines, and polygons. TINS: Triangulated Irregular Networks Formed by using Delaunay Triangulation which is an iterative process of connecting points with their two nearest neighbors to form triangles. Raster data model:- Storage increases with the square of the resolution. Elements: 1. Cell value. Each cell in a raster carries a value, which represents the characteristic of a spatial phenomenon at the location denoted by its row and column. The cell value can be integer or floating-point. 2. Cell size. The cell size determines the resolution of the raster data model. 3. Raster bands. A raster may have a single band or multiple bands. 4. Spatial reference. Raster data must have the spatial reference information so that they can align spatially with other data sets in a GIS. Attribute data is stored logically in flat files. Cell by cell: row n: 0110 Run length encoding: 23 Quad tree or hierarchical encoding DOQ is a image prepared from an aerial photograph or other remotely sensed data, in which the displacement caused by camera tilt and terrain relief has been removed. DEM is a digital representation of a topographic surface. It is mutli-faceted. Data sources:
  • 4. Data capture: Surveys,RS,Digitization Data inputs/ sources: Maps, orthophotos, statistical reports, Satellite Imagery,GPS Input is : - Time consuming - Labour intensive and error prone - Accuracy of GIS analysis rests on accuracy of input data - Expensive Selection of input data: depends on price, availability, spatial analysis required, scale, format, available skills and hardware and software • Federal Geographic Data Committee (FGDC) • Geospatial One‐Stop (GOS) • US Geological Survey (USGS) Metadata describes the characteristics, development and origin of the spatial data. FGDC - Identification Information (Title, geographic data covered) - Data Quality Information (positional, attribute, completeness, sources of information, methods to produce spatial data) - Spatial Data Organization Information (Raster or Vector) - Spatial Reference Information (Datum, Projections, Coord Sys) - Distribution Information (Information about obtaining dataset) - Metadata Reference Information (currency of the metadata and responsible party) Geodesy, is the scientific discipline that deals with the measurement and representation of the earth, its gravitational field, and other geodynamic phenomena, such as crustal motion, oceanic tides, and polar motion. Coordinate systems: PCS (Flat, inches feet metres), GCS( curved , Degrees minutes seconds). 60 N 45 E Conversion of polar to Cartesian:
  • 5. Transformation is the projection of a digitized map or image, in some cases from its original coordinate system, onto a new coordinate system. Two main types :- map to map and image to map. 4 methods: Affine( angular distortions but parallelism preserved, similarity shape preserved not size, equiarea (area and shape preserved), projective( angular and shape distortions). Affine transformation allows: skew, rotation, differential scaling and translation Affine used for above mentioned trans. , aerial photos need projective trans. And satellite imagery needs polynomial or warping trans. A geometric transformation typically involves three steps.
  • 6. •Step 1 updates the control points to real-world coordinates. •Step 2 uses the control points to run an affine transformation. •Step 3 creates the output by applying the transformation equations to the input features. A quantitative measure of the displacement (the deviation) between the actual (true) and estimated (digitized) locations of the control points is RMS. Resampling in this case means filling each pixel of the new image with a value or a derived value from the original image. – Nearest neighbor: fills each pixel of the new image with the nearest pixel value from the original image – Bilinear interpolation: uses the average of the four nearest pixel values from three linear interpolations – Cubic convolution: uses the average of the 16 nearest pixel values from five cubic polynomial interpolations Map algebra is a language specifically designed for geographic cell‐based systems and provides the basis for cartographic modeling. Uses mathematical expressions to create new grid themes. Arithmetic operators, relational operators, Boolean operators, Functions (trig,log) Raster functions (Output grid generated using input grid as argument): Zonal (cells chosen), local (more than one or one argument), global and focal (cells immediate neighbours only). Uses: Surface generation and analysis (hillshade, viewshed), Data reclassification, Transformations, Distance Analysis (shortest path, cost weighted). Buffer made. Layer of important features created, all queries applied and select by attributes for final results. Statistical local function Overlay functions: union , intersect , identity No data in cell no data in output ( set condition otherwise default value is -9999)
  • 7. Raster data model Vector data model Advantages Can store photos Processing of large data sets is easier once topological relations between features are established Simple data structure Prints are aesthetically pleasing Easier Spatial analysis especially overlay (Grid based coincidence) - Can accurately represent continuous phenomena Can accurately represent discrete features Disadvantages Prints appear blocky Cannot store photos Processing of large datasets is time consuming Cannot represent continuous spatial variability accurately Quality and productivity largely depends on resolution Spatial Analysis is time consuming without a developed topology - Complex data structure Photo vs remote Quantitative and qualitative Geometry vs radiometry Visible vs invisible Small area coverage vs large area coverage Uses metadata: Identification of source, techniques of obtaining/ Projection and coordinate systems/ scale/cost/availability Organization of spatial data/ developmental history Data sharing possible Data interpretation techniques
  • 8. Uses GIS: Monitoring weather, disaster management, traffic management, urban and regional planning, Crop yields, Effects of different phenomena on environment. Uses Spatial analysis: Identifying developmental patterns, trends , making predictions, modeling, monitoring changes in environments and their effects. Digitizing adva. And disadva.:- Automatic error detection vs error prone Enabling spatial analysis and easier interpretation vs Slow process Transformation possible vs need of digitizing equipment UTM: 84 n to 80 S, 60 zones (6 deg. Each) East –west, Transverse Mercator projection, Alphabet zones 20 north-south. Cartesian system. Clipping, dicing Mosiacing, raster bands AOI, Inquire box, Coordinates Annotations, dynamic labels Graduated color , graduated symbol, dot density, proportional symbol Discrete color, unique color, classified, Natural breaks is the default method. Developed by the cartographer George Jenks, it creates classes according to clusters and gaps in the data. Equal interval creates classes of equal va lue ranges. If the range of values is 1 to 100 and the number of classes is 4, this method will create classes from 1-25,26- 50,51-75, and 76-100. Defined interval resembles equal interval except that the interval determines the number of classes rather than the other way around. If the range of values is 1 (Q 100, and you choose an interval of 10, this method will create 10 classes: 1- 10, 11-20, 21-30, and so on.
  • 9. Quantile creates classes containing equal numbers of features. If you choose five classes for a layer with 100 features, this method will create class breaks so that 20 features fall into each class. The value range varies from class to class. Standard deviation creates classes according (Q a specified number of standard deviations from the mean value. Geometric intervals creates classes based on class intervals that have a geometric series. A geometric series is a pattern where a constant coefficient multiplies each value in the series. It produces a result that is visually appealing, cartographically comprehensive, and minimizes variance within classes.