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What is GIS?


GIS, Geographic Information System, is a computer-based tool for mapping and analyzing things that exist and events that happen on Earth. Examples are natural disasters, overpopulation, pollution, war, and all other major challenges in the world today – all that have a critical geographic dimension. With GIS, we can perform better and faster tasks of creating maps, integrating information, visualizing scenarios, solving complicated problems, presenting powerful ideas, and developing effective solutions. Today, GIS is widely used by individuals, private and public organizations, schools, governments, and businesses. For instance, GIS is used by enterprise to locate new businesses sites, explain events, predict outcomes, and plan strategies. In GIS technology, common database operations such as query and statistical analysis are integrated with the unique visualization and geographic analysis benefits offered by maps.

GIS stores information about the world as a collection of thematic layers that can be linked together by geography.

Geographic Reference of Geographic Information

  1. Explicit: Latitude, longitude, or national grid coordinate
  2. Implicit: Address, postal code, census tract name, forest stand identifier, and/or road name

Geocoding is a process used to create an explicit geographic reference (multiple locations) from implicit references (descriptions such as addresses). This is used to locate features – such as a business, event, or a natural disaster (flood) – for analysis.

Models of Geographic Information (for Storing Data)

  1. Vector Model: Encodes and stores information about points as a single x, y coordinate, lines (roads and rivers) as a collection of point coordinates, and polygonal features (sales territories) as a closed loop of coordinates. It is more useful to describe discrete features than to describe continuously varying features (soil type as opposed to accessibility costs for hospitals).
  2. Raster Model: Used to model continuous features. It consists of a collection of grid cells (like a scanned map).

Components of GIS

GIS integrates the following components: hardware, software, data, human resources, and methods.

Computer on which GIS operates. Includes monitor, input devices, and printer.
Provides functions and tools needed to store, analyze, and display geographic information.
Example: ArcView 3.1 and ARC/INFO 7.2.1. Key software components: Tools for the input and manipulation of geographic information, a database management system (DBMS), and tools that support geographic queries, analysis, and visualization.
The most important component. Geographic data and related tabular data can be collected in-house or purchased from a commercial data provider. GIS will integrate spatial data with other data resources and can even use a DBMS – used by most organizations to organize and maintain their data – to manage spatial data.
Human Resources
GIS technology is of limited value without the people who manage the system and develop plans for applying it to real-world problems. GIS users range from technical specialists who design and maintain the system to those who use it to help them perform their everyday work.
A successful GIS operates according to a well-designed plan and business rules, which are the models and operating practices unique to each organization.

Five Processes Performed by GIS

Data has to be converted from paper maps into digital format in a process called digitizing. This can be done either manually or with a scanning technology. Some data is available in digital format and can be obtained from data suppliers.
Data must be transformed to the same scale (degree of detail or accuracy) before integrating it.
Large collections of data are stored, organized, and managed in a database management system (DBMS). GIS uses relational design, in which data is stored as a collection of tables. Common fields link these tables.
Query and Analysis
Query questions like "How far is it between two places?" "Where is land zoned for industrial use?" Analytical questions like "If I build a new highway here, how will traffic be affected?" "Where are all the sites suitable for building new houses?" GIS uses buffering to determine the proximity relationship between features.
Example: What is the total number of customers within 20 kilometers of this store? An overlay, or spatial join, can integrate data on soils, slope, and land ownership with tax assessment. Different data layers are integrated together.
Maps are very efficient at storing and communicating geographic information. In GIS, the results and map are integrated with three-dimensional views, reports, photographic images, and other output (multimedia).

Advantage of Using GIS

  1. GIS allows the user to bring all types of data together based on the geographic and locational component of data
  2. GIS maps display many layers of useful information
  3. Visualizes scenarios and manages data
  4. Relationships between data become more apparent and data becomes more valuable
  5. Reduced costs to businesses
  6. Aids in decision-making (location of new housing: low-risk area or close to population center)
  7. Presents powerful ideas

Global Positioning System (GPS)

The Global Positioning System uses satellites and computers to compute positions anywhere on earth. It is a system of satellites that allow a user with a receiver to decode time signals and convert the signals from several satellites to a position on the Earth's surface For this project, GPS was used to connect an inventory of housing conditions with a GIS map. GPS data will be gathered directly from locations (cities in Kosovo). A person will go around a house and GPS will help them to know where the house is located. The information will be used in GIS Kosovo map. Separate data with information on the inventory of housing conditions will be collected and stored in a database. This is not a major goal of the project however.

Layers/Themes of a GIS Kosovo Map

The following are layers/themes that might be considered to create the map:

  1. Cities: Gives us information about cities in Kosovo and cities of neighboring countries.
  2. Political Boundaries: To see where each city in Kosovo is separated either with another country or city. This layer will also give us information on how large or small a city is.
  3. Population: Provides information on the most or least populated cities of Kosovo.
  4. Total Number of War Crimes Plotted Across a Region: Provides information on the region in which crimes were committed as well as which regions have high crimes totals.
  5. Military Units: Provide information where military bases were located.
  6. Mass grave sites: Where people were buried. A massacre might have been committed at that region.
  7. Events Plotted Through Time: Provides information on what types of crimes or events occurred through time


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