The below mentioned article will help you to prepare a project report on Geographic Information System (GIS):- 1. Definitions of GIS 2. Components of GIS 3. Sources 4. Application.
Contents:
- Project Report on the Definitions of GIS
- Project Report on the Components of GIS
- Project Report on the Sources of GIS
- Project Report on the Application of GIS
Project Report # 1. Definitions of GIS:
(a) Toolbox-Based Definitions:
‘A powerful set of tools for collecting, storing, retrieving at will, transforming, and displaying spatial data from the real world’. ‘a system for capturing, storing, checking, manipulating, analysing, and displaying data which are spatially referenced to the Earth’ (Department of Environment, 1987). ‘an information technology which stores, analyses, and displays both spatial and non-spatial data’.
(b) Database Definitions:
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‘A database system in which most of the data are spatially indexed, and upon which a set of procedures operated in order to answer queries about spatial entities in the database’.
‘any manual or computer based set of procedures used to store and manipulate geographically referenced data’.
(c) Organization-Based Definitions:
‘An automated set of functions that provides professionals with advanced capabilities for the storage, retrieval, manipulation, and display of geographically located data’.
‘an institutional entity, reflecting an organisational structure that integrates technology with a database, expertise and continuing financial support over time’.
‘a decision support system involving the integration of spatially referenced data in a problem solving environment’.
Project Report # 2. Components of GIS:
Geographical information systems have three important components-computer hardware, sets of application software modules, and a proper organisational context including skilled people-which need to be in balance if the system is to function satisfactorily.
(i) Computer Hardware:
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The computer had a hard disc drive for storing data and programmes, but extra storage can be provided via a network or by digital type cassettes, optical CD-ROMs, and other devices. A digitizer or scanner is used to convert maps and documents into digital form so that they can be used by the computer programme.
A plotter or a printer or any other kind of display device is used to present the results of the data processing. The general hardware components of a geographical information system are presented in Fig. 26.23.
(ii) GIS Software:
These software’s may be split into five functional groups:
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(a) Data input and verification.
(b) Data storage and database management,
(c) Data output and presentation,
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(d) Data transformation,
(e) Interaction with the user.
Data input covers all aspects of capturing spatial data from existing maps, field observation and sensors (including aerial photography, satellites and recording instruments) and converting them ‘to a standard digital form. The main software components of a geographical information system are shown in Fig. 26.23.
Data storage and database management concerns the way in which data about the location linkage (topology) and attributes of geographical elements (points, lines, areas, and more complex’ entities representing objects on the earth’s surface) are structured and organised, both with respect to the way they must be handled in the computer and how they are perceived by the users of the system.
Data output and presentation concern the ways the data are displayed and how the results of analyses are reported to the users. Data may be presented as maps, tables, and figures in a variety of ways ranging from the ephemeral image on the computer screen, through hardcopy output drawn on printer or plotter to information recorded on magnetic media in digital form.
Data transformation embraces two classes of operation, viz.:
(a) Transformations needed to remove errors from the data or to bring them up to date or to match them to other data sets, and
(b) The large array of analysis methods that may be applied to the data in order to achieve answers to the questions asked of the GIS.
GIS designers have realized that the requirements to users to retrieve and transform data are unlimited .Therefore most systems provide a range of interfaces by which the user can interact with the system The simplest are menu-driven commands that can be selected by simply pointing and clicking with the mouse, and this is an efficient way of providing complex functionality for ordinary users.
(iii) Organisational Set-Up:
By and large, for proper analysis of information using GIS require appropriate set-up of computer network and skilled man-power. Often there are target-specific training for developing appropriate man-power. However all aspects of dealing with geographical information involve interactions with people (Fig. 26.24).
Project Report # 3. Sources of GIS:
Creating a GIS database is a complex operation involving data capture, verification, and structuring process. Because raw geographical data are available analogues or digital forms, such as maps, aerial photographs, satellite images, or tables, a spatial database can be built in several-not mutually exclusive-ways.
These are:
Acquire data in digital forms from a data supplier.
1. Digitize existing analogue data,
2. Carry out one’s own survey of geographic entities;
3. Inter-plate from point observations to continuous surfaces.
In all cases the data must be geometrically registered to a generally accepted and properly defined coordinate system and coded so that they can be stored in the internal database structure of the GIS being used. For many people the most common source of geographical data is the paper or digital topographic or thematic map, which is a graphical representation of the distribution of sptatial phenomena.
Images derived from optical and digital remote sensing systems mounted in aircraft and satellite provide much spatial information over many levels of temporal and spatial resolution.
A wide range of scanners mounted in satellites or aircraft also provide digital data directly. In addition, the traditional means of collecting geographical data is by ground or field surveys to record sample values at known locations, using instruments ranging from questionaries’ and soil augers to automated chemical probes.
It is most important that all spatial data in a GIS are located with respect to a common frame of reference. It is further essential for GIS and spatial analysis that all data are referenced to the same coordinate system.
Geo-referencing of Data:
In practice, ground and field surveys are geo-referenced in many ways. Ground checks are needed to locate aerial photographs and satellite images correctly. The boundaries for cadastral systems are surveyed accurately on the ground using laser theodolites, as are the locations of infrastructure and utilities (roads, electricity and telephone cables, gas, water, and sewerage pipes).
Sources of demographic and socio-economic data such as the census are linked to less accurate, cartographically defined areal units as the basic spatial references. A similar approach is adopted for data collected by administrative or municipal authorities.
Subsequently the problem of defining and recording the location of a data point has been eased through the development of global position systems (GPS) which are being used increasingly in many types of data collection exercise, often in tandem with data-loggers.
Project Report # 4. Application of GIS:
The applications of GIS are:
1. Conducting resource inventory as an application of standard classification techniques and simple integration of the information in a GIS to provide the required management information;
2. Resource monitoring as a more advanced application of classification, with simple GIS integration to provide the required management information;
3. Estimation of resource status using remote sensing;
4. Resource modelling by using remote sensing and GIS to predict potential outcomes, to support the management of resources; and.
5. Estimation of crop production with the aid of GIS data.
Example:
Accurate information on land and environmental resources is essential to effective land use planning. Key sources of information include topographic maps, aerial photos, satellite, mages, and data desired from geographic system (GIS).
The process of plan compliance with land use planning involves the following steps:
For comprehensive studies and for planning undertaken on a countrywide basis, aerial photography (RS method) are recommended as a way of collecting accurate and appropriate information, especially when the areas have not been adequately studied in the part. Aerial photography can save time and expenses, and the photographs taken can generally be merged with data gather from field operations.
i. Global Positioning System (GPS):
The satellite navigation system or global positioning system (GPS) is a new technique used by the geographers for locating spatial phenomena. This technique is based on the principles of trilateration which have been used by surveyors for centuries.
To understand how a GPS works, it is important to appreciate that the system has five components.
These are:
1. The satellite constellation (either American NAVSTAR or Russian GLONASS systems)
2. The satellite control and monitoring stations;
3. The national and regional GPS base station networks;
4. The GPS receivers, and
5. The users.
Usually, GPS has been used in field mapping, geo-referencing, and also in digital elevation model verification.
ii. Global Positioning Systems (GPS) Application:
Traditionally, geographers have used numerous techniques to determine both the relative and actual location of spatial phenomena. These have ranged from the very accurate and precise techniques of the surveyors to the more general method of the social scientist. Recently, however, a new technique for locating spatial phenomena has found particular favour with geographers.
This is the satellite navigation system or global positioning system (GPS). These portable Ideational devices can be mounted on a vehicle, earned in a backpack or held in the hand and used to record location at almost any point on the earth’s surface.
GPS is a set of satellites and central systems that allow a specially designed receiver to determine its location anywhere on earth 24 hrs. a day. Two main systems exists-the American (NAVSTAR) and the Russian (GLONASS) system.
The GPS framework has a satellite constellation, the satellite control and monitoring stations the national and regional GPS base station network, receivers and the user ends. By and large, GPS technology is feasible and effective in a variety of research areas where other surveying and mapping techniques would be impractical. For field mapping, or geo-referencing of resource data, GPS technology is now used widely.