UPSC Exam  >  UPSC Notes  >  Geology Optional Notes for UPSC  >  The Geographic Information System and Global Positioning System (GPS)—its applications

The Geographic Information System and Global Positioning System (GPS)—its applications | Geology Optional Notes for UPSC PDF Download

Introduction

Geographic Information System (GIS) and Global Positioning System (GPS) are powerful tools used in various fields for data analysis, visualization, and location-based services.

Geographical Information System (GIS)

  • GIS comprises different components that work together to capture, store, manipulate, analyze, and present spatial or geographical data.
  • GIS data exists in various formats, such as vector and raster formats, each suitable for different types of spatial data representation.
  • Vector and raster formats offer distinct advantages and are used in different applications.
  • Data input in GIS involves collecting geographic data and entering it into the system for processing.
  • Basic GIS functionality includes mapping, spatial analysis, and data visualization.
  • GIS can provide answers to a wide range of spatial questions, aiding decision-making processes in different industries.

Applications of GIS

  • GIS finds applications in atmospheric sciences for weather forecasting, climate modeling, and environmental monitoring.

Global Positioning System (GPS)

  • GPS consists of three main segments: the space segment, control segment, and user segment, working together to provide precise location data.
  • The functioning of GPS relies on a network of satellites orbiting the Earth and ground stations that monitor and control the system.
  • Indian Global Positioning System - GAGAN enhances the accuracy of GPS in the Indian region.

Applications of GPS

  • GPS is used for precise timing synchronization in various systems and applications.
  • In the transportation sector, GPS aids in navigation, route planning, and tracking of vehicles on roads and highways.
  • GPS is crucial for space exploration, satellite communication, and satellite positioning.
  • In agriculture, GPS technology assists in precision farming, mapping fields, and managing agricultural resources efficiently.
  • Surveying and mapping benefit greatly from GPS technology, allowing for accurate data collection and mapping of terrains.
  • Precision agriculture utilizes GPS for tasks like soil sampling, crop monitoring, and yield optimization.

Summary

In conclusion, GIS and GPS are indispensable tools with diverse applications across various industries, revolutionizing the way we collect, analyze, and utilize spatial data for improved decision-making and efficiency.

Introduction

  • Geographical Information System (GIS) is a contemporary and effective tool utilized for managing spatial data. It serves as an integrated computer-based system that combines geography and information seamlessly.
  • GIS finds extensive applications across various disciplines due to its versatility and functionality.
  • Global Positioning System (GPS) complements GIS by providing real-time positional data, expanding the capabilities of geographical information systems.
  • GIS and GPS work in tandem to offer a range of applications that enhance decision-making processes and data analysis.

GIS Explained

  • GIS enables users to capture, store, analyze, and present spatial data effectively.
  • It allows for the creation of maps, visualization of data, and understanding of spatial relationships.
  • GIS is used in urban planning, environmental management, disaster response, and more.

GPS Functionality

  • GPS provides accurate positioning information using satellites, enabling precise location tracking.
  • It is utilized in navigation systems, surveying, emergency services, and fleet management.

Applications of GIS and GPS

  • GIS is applied in agriculture for precision farming, optimizing crop yields and resource management.
  • GPS is used in transportation for route planning, vehicle tracking, and traffic management.
  • GIS finds applications in public health for disease mapping, epidemiology studies, and healthcare planning.
  • GPS aids in disaster management by providing real-time data for response efforts and evacuation procedures.
  • Understanding Geographical Information System (GIS)

    • GIS serves as a comprehensive system comprising hardware, software, and processes tailored to aid in capturing, managing, manipulating, analyzing, modeling, and displaying spatially-referenced data. Its primary aim is to resolve intricate planning and management dilemmas efficiently.
    • It functions as an integrated system specifically crafted to handle both spatial and attribute data. In essence, GIS equips users with tools to work seamlessly with spatially-referenced information alongside a variety of non-spatial data.
    • For instance, GIS can be used in urban planning to map out areas prone to flooding based on historical data and topographical information. This enables city officials to make informed decisions regarding infrastructure development and disaster preparedness.
    • Furthermore, in environmental science, GIS aids researchers in tracking wildlife migration patterns by overlaying GPS data onto geographic maps. This integration offers valuable insights into animal behavior and habitat preferences.

Components of GIS

  • Hardware: The hardware component of GIS comprises the computer system where GIS operates. It includes input and output devices such as scanners, digitizer boards, printers, and plotters.
  • Software: GIS software offers tools for storing, analyzing, and displaying geographic information. Key software components include data input and verification, data storage and database management, data transformation, data output and presentation, and interaction with the user.

    • Data input and verification
    • Data storage and database management
    • Data transformation
    • Data output and presentation
    • Interaction with the user
  • Data: Data is a crucial component of GIS, divided into spatial data and attribute data. Spatial data pertains to objects in geographical space, aiding in global positioning. Attribute data supplements spatial features with additional information.

    • Spatial data - Examples include maps, satellite images, and GPS coordinates.
    • Attribute data - Examples include population statistics, land use classifications, and temperature readings.
  • Method: A successful GIS operates based on a well-structured plan and organizational rules unique to each entity. Various techniques are employed for map creation and project implementation.

GIS Data Formats and Data Input

Formats of GIS Data

  • Vector Format:
    • GIS represents spatial data in two main formats: Vector and Raster.
    • In Vector format, real-world features like points, lines, and polygons are used to create objects.
    • Points are described by single x, y coordinates, lines by sets of point coordinates, and polygons by closed loops of coordinates.
    • For example, a river can be represented as a linear feature with a collection of point coordinates.
  • Raster Format:
    • Raster data is structured as square pixels, with each pixel containing a single value.
    • Continuous data like elevation and vegetation are commonly represented using the raster model.
    • This format divides the study area into a grid of cells, each representing a specific value.

Data Input in GIS

  • When bringing spatial data into GIS software, it must first be converted into a digital format.
  • Sources of spatial data include satellites, GPS, and paper maps.
  • Digitizing:
    • This process converts paper maps into digital data suitable for GIS software.
    • Digitizing can be done using tools like a digitizer or scanner.
    • On-screen digitization involves manual digitizing on a computer monitor using a raster image or toposheet as a reference.

Basic GIS Functionality

Geographic Information Systems (GIS) software is a powerful tool that combines mapping capabilities for spatial data with database management functions for attribute data. The fundamental functionalities of GIS include:

  • Querying both spatial and attribute data:
  • Users can ask questions about both the location and characteristics of data. For example, a city planner might query a GIS to find all residential areas within a specific distance from a park.

  • Manipulating the spatial component of the data:
  • GIS allows users to edit and modify the geographic features in the data. This could involve tasks like moving a road, resizing a building, or adjusting a boundary.

  • Buffering:
  • Buffering identifies all points within a specified distance of a particular feature. For instance, creating a buffer around a river to see all areas within a 100-meter distance for environmental analysis.

  • Overlaying:
  • Overlaying involves combining multiple layers of data to create a new layer. An example could be overlaying a map of population density with a map of healthcare facilities to identify underserved areas.

  • Areal Interpolation:
  • This process estimates values for locations where data is not available by considering surrounding values. For example, estimating the population density of an unrecorded area based on the densities of neighboring regions.

Questions GIS Can Answer

  • Location: Queries in GIS can determine what is located at specific coordinates. For instance, you can ask "What is at this particular location?"
  • Condition: GIS helps in identifying the whereabouts of various elements. An example question would be "Where exactly is this specific feature?"
  • Trends: Through GIS, one can analyze changes over time. An inquiry could involve asking "What alterations have occurred since a certain point?"
  • Patterns: GIS aids in recognizing spatial arrangements. You might inquire about "What spatial configurations are present in this area?"
  • Modeling: GIS facilitates simulations and predictions. You can pose questions like "What would happen if certain conditions are altered?"
  • Spatial Questions: GIS can address queries related to spatial relationships, such as "Which centers are situated within a 10-kilometer radius of each other?"
  • Non-spatial Questions: Besides spatial aspects, GIS can also answer non-spatial questions related to data analysis and interpretation.

Applications of Geographic Information Systems (GIS)

  • GIS is a powerful technology used to integrate spatial and attribute data, enabling various forms of geographical analysis.
  • It supports traditional methods like map overlay analysis and facilitates new types of analysis and modeling that manual methods cannot achieve.
  • With GIS, one can map, model, query, and analyze large datasets stored within a unified database.
  • The development of GIS has benefited from innovations across disciplines such as Geography and Cartography.
  • GIS finds extensive applications in government, business, and research across a wide range of fields:

    • Environmental resource analysis
    • Land use planning
    • Locational analysis
    • Tax appraisal
    • Utility and infrastructure planning
    • Real estate analysis
    • Marketing and demographic analysis
    • Habitat studies
    • Archaeological analysis
  • Furthermore, GIS serves as a valuable tool in various scientific and technological disciplines:

    • Photogrammetry
    • Remote Sensing
    • Surveying
    • Geodesy
    • Civil Engineering
    • Statistics
    • Computer Science
    • Operations Research
    • Artificial Intelligence
    • Demography
  • Many other branches of social sciences, natural sciences, and engineering also benefit from GIS applications.
  • The interdisciplinary nature of GIS technology leads to diverse and fascinating applications, drawing on its rich heritage.

Applications of Geographic Information Systems (GIS)

  • One of the initial significant applications of GIS was in natural resources management, encompassing the management of:

    • wildlife habitats
    • wild and scenic rivers
    • recreation resources
    • floodplains
    • wetlands
    • agricultural lands
    • aquifers
    • forests
  • Facilities management is another major area where GIS has been extensively used. Applications in this field include:

    • locating underground pipes and cables
    • balancing loads in electrical networks
    • planning facility maintenance
    • tracking energy use
  • Local, state, and federal governments have found GIS invaluable in land management, with common applications in areas such as:

    • zoning and subdivision planning
    • land acquisition
    • environmental impact policy
    • water quality management
    • maintenance of ownership
  • Recent innovative uses of GIS have focused on information derived from street networks, proving beneficial in:

    • address matching
    • location analysis or site selection
    • development of evacuation plans
  • The scope of GIS applications continues to expand as systems evolve. Some of the latest applications have ventured into unexpected domains. Noteworthy examples include:

    • Global Change and Climate History Project
    • Emergency Response Planning
    • Site Selection of Water Wells
    • Wildfire Hazard Identification and Mitigation System

By effectively utilizing GIS, organizations can enhance decision-making processes, optimize resource management, and improve overall operational efficiency. For instance, in the field of wildlife habitat preservation, GIS enables conservationists to identify critical habitats, track migration patterns, and implement targeted conservation strategies. Similarly, in urban planning, GIS aids in determining optimal locations for infrastructure development, analyzing traffic flow patterns, and mitigating environmental risks.Moreover, the integration of GIS in emergency response planning has revolutionized disaster management practices. By leveraging GIS technology, emergency responders can swiftly identify high-risk areas, coordinate rescue operations effectively, and allocate resources efficiently during crises like natural disasters or public health emergencies.In conclusion, GIS serves as a versatile tool with a wide array of applications across various sectors, playing a pivotal role in driving informed decision-making, promoting sustainable development, and addressing complex societal challenges. As GIS technologies continue to advance, the potential for innovative applications across diverse fields remains limitless.

GIS Applications in Atmospheric Sciences

  • Assessment of Wind/Storm Speed using Interpolation

GIS and geospatial technologies are increasingly valuable in atmospheric sciences, aiding in weather, climate, and hydrometeorology studies as well as societal impact assessments.

In GIS, Inverse Distance Weighted (IDW) interpolation is commonly applied to convert point data into raster overlays. This technique helps in creating contour lines through interpolated values on a regular grid, enabling the creation of vector contour maps or raster-shaded maps.

  • Average Annual Lightning Strike Density

Lightning strike density can be mapped using coarse resolution raster data. For instance, in a given area, the density of lightning strikes can be visualized and analyzed to understand patterns and trends.

Wind Speed Mapping Techniques in GIS

  • TIN Method Overview: The Triangular Irregular Network (TIN) is a GIS tool utilizing a vector data structure. It constructs a surface using triangles formed by nearby points.
  • Wind Speed Mapping: Wind speed can be effectively mapped using the TIN method, creating a continuous raster surface model for visualization.
  • Linear Models in GIS: Linear models are employed to establish relationships between variables, aiding in the development of predictive models. For instance, wind speed predictions or storm behavior analysis can utilize linear modeling.

Applications of Wind Speed Mapping Techniques

  • Tracking of Tornado Outbreaks: By analyzing wind speed patterns, GIS can help predict and track tornado outbreaks, enabling early warnings and disaster management.
  • Tracking of Tsunami Arrival: GIS applications can map wind speeds to predict tsunami arrival times, aiding in coastal area evacuation and preparedness.
  • Speeding Power Restoration after a Storm: Utilizing wind speed mapping, GIS can assist in quickly identifying areas most affected by storms, facilitating rapid power restoration efforts for efficient disaster recovery.

Global Positioning System (GPS)

  • The Global Positioning System (GPS) is a satellite-based navigation system providing positioning, navigation, and timing services.
  • Originally developed by the US military as NAVSTAR in the 1950s, GPS was initially restricted to military use before becoming available to civilians worldwide.
  • Today, GPS offers continuous, free services globally to all users.
  • Other countries have also created their own satellite navigation systems, such as GLONASS (Russia), Galileo (Europe), and Beidou (China).

```html

Segments of GPS

  • Space Segment
    • The Space Segment of GPS comprises a constellation of satellites that emit signals enabling users to ascertain their position, velocity, and time.
    • Key functions of GPS satellites include:
      • Receiving and storing data from control segment stations.
      • Maintaining precise time using onboard atomic clocks.
      • Transmitting information and signals to users on two L-band frequencies.
    • The Space Segment involves 24 operational satellites and five backups orbiting the Earth in six planes. Each satellite is positioned at a 55-degree angle to the equator at an altitude of approximately 20,200 kilometers.
    • Every satellite completes two orbits around the Earth every 24 hours, with an orbital speed of about 4 km per second.
    • Each GPS satellite emits a distinct navigational signal on two L-band frequencies to counter the ionospheric propagation effect and ensure signal accuracy. These signals are highly directional and can be impeded by solid obstacles, though they can penetrate clouds but may be obstructed by foliage depending on its density and type.
  • User Segment
    • The User Segment of GPS comprises the devices used by individuals to access and utilize GPS data for navigation and positioning purposes.
    • Users interact with GPS through various devices like smartphones, navigation systems, and wearables, enabling them to receive and interpret satellite signals for location tracking.
  • Control Segment
    • The Control Segment of GPS involves ground stations responsible for tracking and managing the GPS satellites, ensuring their proper functioning and data transmission.
    • Control segment stations monitor satellite orbits, maintain their atomic clocks, and send necessary commands to adjust satellite positions and functions.

5.1.2. Control Segment (CS)

  • All the five aforementioned stations are Monitoring Stations, equipped with GPS receivers to track the satellites. The resulting tracking data is sent to the Master Control Station.
  • Colorado Springs is the Master Control Station (MCS), where the tracking data is processed to compute the satellite ephemerides and clock corrections. It is also responsible for initiating space segment operations like spacecraft maneuvers, signal encryption, and satellite clock maintenance.
  • Ascension Island, Diego Garcia, and Kwajalein are Upload Stations facilitating the transmission of data to the satellites. This data includes orbit and clock correction information within the navigation message, along with command telemetry from the MCS.

Overall operations of the Control and Space Segments are overseen by the U.S. Air Force Space Command, Second Space Wing, Satellite Control Squadron at the Falcon Air Force Base, Colorado. The GPS satellites move at high velocity (4 km/s) within a regular orbit pattern, determined by their initial position, velocity, and external force fields.

5.1.3. User Segment

  • The User Segment refers to the component of the GPS system that interacts directly with users, enabling them to determine their positions accurately.
  • Users access signals from the GPS satellites through GPS receivers, which calculate their positions based on the signals received from multiple satellites.
  • GPS receivers utilize a process called trilateration to determine the user's position by measuring distances from at least three satellites and intersecting their spheres of possible locations.
  • Applications of the User Segment include navigation systems in cars, smartphones, aviation, surveying, and various location-based services.

Functioning of GPS

  • The Global Positioning System (GPS) comprises satellites, ground stations, and receivers.
  • Satellites transmit position information, ground stations control satellites and update data, and receivers collect data to compute locations globally.
  • A common misconception is that GPS receivers send information to satellites, whereas they only receive data.

Indian Global Positioning System - GAGAN

In August 2001, the Airports Authority of India and ISRO agreed to establish the GAGAN system.

GAGAN, which stands for GPS Aided Geo Augmented Navigation, went through three phases:

  • Technology Demonstration System (TDS)
  • Initial Experimental Phase (IEP)
  • Final Operational Phase (FOP)

The GAGAN system underwent stability tests and was successfully completed in June 2013.

GAGAN aims to enhance GPS accuracy, availability, and integrity for various transportation modes, including aviation, maritime, highways, and railways.

It ensures precise position reporting for better Air Traffic Management and benefits multiple sectors like defense, security, telecom, and personal users of location-based applications.

  • Applications of GPS

    • Timing
    • In addition to longitude, latitude, and altitude, the Global Positioning System (GPS) plays a crucial role in providing precise time information. GPS satellites are equipped with atomic clocks that offer highly accurate time data to GPS signals. By decoding these signals, GPS receivers can synchronize with these atomic clocks, allowing users to determine time with extreme precision, up to 100 billionths of a second. This eliminates the need for individuals to own and maintain atomic clocks, benefiting various sectors that rely on precise timing.

      For instance, communication systems, electricity grids, and financial networks heavily depend on accurate timing for synchronization and operational efficiency. The availability of GPS time has resulted in cost savings for companies that require precise timing, leading to significant advancements in operational capabilities across industries.

    • Roads and Highways
    • Congestion on roads, streets, and transit systems globally leads to substantial productivity losses amounting to billions of dollars annually. Additionally, congestion causes property damage, personal injuries, increased air pollution, and inefficient fuel consumption. The Global Positioning System (GPS) offers a solution by enhancing efficiency and safety for vehicles navigating highways, streets, and mass transit systems.

      GPS technology significantly improves the routing and dispatch processes for commercial vehicles, reducing or eliminating many associated challenges. Countries utilize GPS for surveying road and highway networks, pinpointing various features like service stations, emergency services, entry and exit ramps, and road damages. This information is crucial for Geographic Information System (GIS) data collection, aiding transportation agencies in cutting maintenance costs, improving service efficiency, and ensuring driver safety.

Space Exploration Benefits of Global Positioning System (GPS)

  • Navigation Solutions:
    • Enhancing orbit determination precision and reducing ground control crew requirements by utilizing space-qualified GPS units. For instance, GPS aids in accurately tracking the position of satellites in space, enabling efficient navigation for spacecraft.
  • Attitude Solutions:
    • Substituting costly on-board attitude sensors with cost-effective multiple GPS antennae and specialized algorithms. This advancement helps in maintaining and controlling the orientation of spacecraft at a lower expense. For example, GPS technology can be employed to adjust the orientation of satellites for optimal performance.
  • Timing Solutions:
    • Replacing expensive spacecraft atomic clocks with economical and precise GPS receivers for accurate timekeeping. By utilizing GPS for time synchronization, spacecraft can maintain precise timing for various operations such as data transmission and maneuver planning.

`In the context of space exploration, the Global Positioning System (GPS) plays a crucial role in transforming how nations engage in activities beyond Earth's atmosphere. Here are the key benefits of utilizing GPS technology:- Navigation Solutions: - GPS significantly enhances the precision of determining orbits and reduces the need for extensive ground control crews by employing space-qualified GPS units. This technology ensures accurate tracking and navigation of satellites in space, facilitating efficient spacecraft movements.- Attitude Solutions: - By replacing expensive on-board attitude sensors with cost-effective multiple GPS antennae and specialized algorithms, GPS technology helps in controlling and adjusting the orientation of spacecraft at a reduced cost. For instance, satellites can optimize their positioning using GPS systems for improved operational efficiency.- Timing Solutions: - GPS enables the substitution of costly spacecraft atomic clocks with affordable and precise GPS receivers, ensuring accurate timekeeping for various spacecraft operations. With GPS-based time synchronization, spacecraft can maintain precise timing for tasks like data transmission and maneuver coordination.

  • Aviation
    • Aviators globally utilize the Global Positioning System (GPS) to enhance flight safety and efficiency.
    • GPS offers precise, continuous, and worldwide capabilities, providing seamless satellite navigation services for aviation users.
    • It enables three-dimensional position determination for all flight phases, optimizing air routes and leading to significant time and cost savings.
    • Aircraft flying over data-sparse regions like oceans can safely reduce separation, allowing for more efficient routes and increased revenue.
  • Agriculture
    • The combination of GPS and Geographic Information System (GIS) has facilitated precision agriculture or site-specific farming.
    • These technologies allow real-time data collection combined with accurate position information for efficient manipulation and analysis of geospatial data.
    • GPS applications in precision farming include farm planning, field mapping, soil sampling, tractor guidance, and variable rate applications of inputs.
    • GPS enables farmers to work under low-visibility conditions like rain, dust, fog, and darkness.
  • Surveying and Mapping
    • GPS, with ground augmentations, provides near pinpoint accuracy, enabling rapid and highly accurate surveying and mapping results.
    • This technology significantly reduces equipment and labor hours compared to conventional techniques, allowing for increased efficiency.
    • Professional surveyors and mapping personnel worldwide are increasingly adopting GPS for its accuracy and efficiency.
  • GPS and Precision Agriculture
    • Precision agriculture aims to maximize output by optimizing input, ensuring the right actions at the right place and time.
    • GPS plays a crucial role in precision agriculture by providing ground truth information for analysis and processing of remote sensed images.
    • It allows for direct digital recording of field data, aiding in image analysis, soil sampling, and mapping for improved agricultural production.
    • GPS receivers integrated with computers and software enable users to visualize and utilize various data layers effectively.

Soil Sampling using GPS

Soil sampling is a crucial aspect of precision agriculture, akin to laying a strong foundation for a building. In precision agriculture, understanding the soil across the entire field is essential for effective management of soil-plant relationships.

Grid sampling, a method utilized in precision agriculture, is preferred for its simplicity and accessibility, not requiring extensive soil science expertise. Once soil data is gathered, it can be visualized and analyzed for informed decision-making.

Types of Grid Sampling:

  • Area sampling (grid cell)
  • Point sampling with interpolation (grid point)

To accurately determine and map soil variations within a field, it is imperative to know the precise location of soil samples. Regardless of the grid sampling method employed, the coordinates of soil samples must be accurate. This necessitates the use of a GPS receiver and differential corrections to ensure a precise horizontal position, typically within 1-2 meters, representing the soil sample location.

Once coordinates are obtained, they can be entered into a database on-site. Subsequently, all relevant physical soil data such as texture, pH levels, and nutrient content can be linked to the specific coordinate location for comprehensive analysis and decision-making.

Summary of GIS and GPS

  • GIS (Geographic Information System) is a comprehensive system used for capturing, storing, integrating, manipulating, analyzing, and displaying spatial data.
  • GPS (Global Positioning System) is primarily designed to pinpoint the precise location of an object, aiding in navigation.

Key Components of GIS:

  • GIS comprises Hardware, Software, Data, People, and Method as its major components.
  • Vector and Raster are the two essential data formats utilized in GIS for representing geographical information.

Functions and Segments:

  • Querying, Overlaying, and Buffering are fundamental functions of GIS.
  • GPS is divided into three segments: Space segment (satellites), Control segment (ground stations), and User segment (the receiver).

Global GPS Systems:

  • Various operational GPS service systems worldwide include NAVSTAR (USA), GLONASS (Russia), Galileo (Europe), and India's own Global Positioning System (GAGAN).

Applications of GIS and GPS:

  • GIS and GPS find applications across diverse fields such as transportation, aviation, weather monitoring, disaster management, agriculture, natural resource exploration, and corporate governance.
  • These technologies are crucial for tasks like precision agriculture, land cover change detection, mineral mapping, and societal program implementation and monitoring.

You can view a video on Applications of GIS and GPS for further insights.

The document The Geographic Information System and Global Positioning System (GPS)—its applications | Geology Optional Notes for UPSC is a part of the UPSC Course Geology Optional Notes for UPSC.
All you need of UPSC at this link: UPSC
119 docs

Top Courses for UPSC

Explore Courses for UPSC exam

Top Courses for UPSC

Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

video lectures

,

pdf

,

Summary

,

Viva Questions

,

MCQs

,

past year papers

,

Sample Paper

,

Objective type Questions

,

practice quizzes

,

The Geographic Information System and Global Positioning System (GPS)—its applications | Geology Optional Notes for UPSC

,

ppt

,

Extra Questions

,

Exam

,

The Geographic Information System and Global Positioning System (GPS)—its applications | Geology Optional Notes for UPSC

,

Previous Year Questions with Solutions

,

study material

,

Important questions

,

Semester Notes

,

Free

,

shortcuts and tricks

,

The Geographic Information System and Global Positioning System (GPS)—its applications | Geology Optional Notes for UPSC

,

mock tests for examination

;