Using GIS. GIS Areas and Applications

GIS is widely used. Users include national, state, and local agencies; private business (from delivery companies to restaurants, from engineering to law firms); educational institutions (from universities to school districts, from administrators to researchers); and private citizens. As indicated earlier, the full use of GIS requires software (that can be acquired from a commercial vendor), hardware (which allows running the GIS software), and data (with the information of interest).

Partial use of GIS is possible today with access to the Internet. As indicated by Worboys (18), ‘‘data are only useful when they are part of a structure of interrelationships that form the context of the data. Such a context is provided by the data model.”

Depending on the problem of interest, the data model maybe simple or complex. In a restaurant, information about seating arrangement, seating time, drinks, and food are well defined and easily expressed by a simple data model. Fundamentally, you have information for each table about its location, the number of people it seats, and the status of the table (empty or occupied).

Once a table is occupied, additional information is recorded: How many people occupy the table? At what time was the table occupied? What drinks were ordered? What food was ordered?. What is the status of the order (drinks are being served, food is being prepared, etc.) Questions are easily answered from the above information with a simple data a model (see Fig. 2) such as follows: What table is empty? How many people can be seated at a table? What table seats seven people? Has the food ordered by table 11 been served? How long before table 11 is free again?

Of course, a more sophisticated data model will be required if more complex questions are asked of the system. For example, What is the most efficient route to reach a table based on the current table occupancy? If alcoholic drinks are ordered at a table, how much longer will it be occupied than if nonalcoholic drinks are ordered?

How long will it be before food is served to table 11 if the same dish has been ordered nine times in the last few minutes?

Many problems require a complex data model. A non-exhaustive list of GIS applications that require complex models is presented next. This list gives an overview of many fields and applications of GIS:

Siting of a store: Find, based on demographics, the best location in a region for a new store. Retailers collect ZIP codes information, the corresponding sale amount, and the store location for each transaction. This information can be used in a GIS to show the volume of sales coming from each ZIP code region. Using additional information for each ZIP code region, such as income, lifestyle retailers can determine how far a customer is willing to drive to go to a store. This information can be used to determine the best site for a new store.

Network analysis: Find, for a given school, the shortest bus routes to pick up students. School districts use the postal addresses of students, school locations, and student distribution to plan cost-efficient school bus routes. Some of the products of network analysis for school routing are find students homes, bus stops, and schools on maps; assigns students to closest stop; assign stops to a run and runs to a route; identify district boundaries, walk-zones, and hazardous streets; and generate stop times and driver directions for runs.

Utility services: Applications for utility services include service interruption management, emergency response, distribution, network operation, planning, research, sales, engineering, and construction. An electric company, for example, provides services to residential, commercial, government, nonprofit, and others clients. These services are location-based and require a fast response to irregular situations such as an outage. Outage are responded to by priority. Generally, an outage in a hospital requires a faster response than to a residence. Using GIS, this response is efficient and timely.

Land information system: Generate, using land parcels as the basic unit, an inventory of the natural resources of a region and the property-tax revenue. The geo-spatial description of each parcel, their attributes such as owner, area, number of rooms, value, use, and so on, together with the basic geographic features of the region, such as roads, rivers, streams, and lakes; vegetation; political boundaries; and so on, allows the study and analysis of the region.

Automated car navigation: Having a dataset with enough route information such as the geo-spatial description of roads, their speed limit, number of lanes, traffic direction, status of roads, construction projects, and so on, it is possible to use GIS for real-time car navigation. Questions such as: the recommended speeds, the path to be followed, street classification, and route restrictions to go from location A to location B can be answered during navigation.

Tourist information system: Integrating geo-spatial information describing roads and landmarks such as restaurants, hotels, motel gasoline stations, and so on, allows travelers to answer questions such as follows: What is the difference in driving time to go from location A to location B following the scenic route instead of the business route? Where, along the scenic route, are the major places of interest located? How far is the next four-star hotel? How far am I from the next gasoline station? Some systems allow to reserve a hotel room, rent a car, buy tickets to a concert or a movie, and so on, from the route.

Political campaigns: How to maximize funds and to reach the larger sympathetic audience is basic in a political campaign. Based on population information, political trends, cost, and social-economic level, it is possible, for example, to set the most time-efficient schedule to visit the largest possible number of cities where undecided voters could make the difference during the last week of a political campaign.

Marketing branch location analysis: Find, based on population density and consumer preferences, the location and major services to be offered by a new bank branch.

Terrain analysis: Find the most promising site in a region for oil exploration, based on topographic, geological, seismic, and geo-morphological information.

Driving directions: Find how to go from Point A to Point B based on the postal addresses, which is one of the most popular applications of GIS, and one that only requires access to the Internet. Most computer users are familiar with this application. You type the postal address of your departure place and the postal address of your destination.

A computer program will generate a set of directions to travel. These instructions will be given by naming the major streets and highways you will drive, indicating how to connect from one to the next, and the distance to be traveled in each segment, and time of traveling (based on the legal speed limit). The program will provide you with written instructions or a map displaying the route to be traveled.