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The capability of GIS to analyze data and determine the best locations

Alshehri Mushabab
Technical and Vocational Training Corporation – Saudi Arabia

1- Introduction

In almost all countries in the world the national manpower has been given a complete attention. Ministries, organizations and institutions have been created to meet the needs of the labour market and the enormous development in all aspect of life. The General Organization for Technical Education And Vocational Training (GOTEVOT) in Saudi Arabia is the establishment that has the responsibility of planning and training to implement the government strategy of the workforce. One of the many programs in (GOTEVOT) is technological education. This kind of education is represented by the colleges of technology. These colleges were established to meet technologically the need of the labour market. Also the one of the main objectives of establishing these colleges is to provide the opportunities for enrolment at higher technical education by opening colleges of technology in different regions and cities. (www.gotevot.com)

The problem that will be concerned is the distribution of the colleges of technology in Saudi Arabia. The following two questions need answers. Is there a real need of new colleges of technology? If yes, what are the most suitable locations to be places of new colleges? The answer of the first question is absolutely yes. The need of more colleges becomes a necessity as a result of the population expansion. Another reason is the increase in the number of students who finished high school studying and limited number of the opportunities to find a university seat. This leads to the second question where the new colleges should be.

It is obvious that the cities where no existing college are possible to know easily, but not clear what are the best places to establish new colleges. GIS will help decision makers to know which the suitable cities to build a new college are. In this project the integration of GIS analysis methods will use to identify the current distribution of the existing colleges. Also with a future view this project will recommend the decision makers and present some suggestions about the best places to be locations of new colleges. Population density and the distance to existing college will be the factors that the analysis in GIS deals with.

2- Study area and data sources

As shown in the figure 1 the study area was the whole country of Saudi Arabia that represents 1.44 % of the world area (2,149,690 kmĀ²) and 0.37 % of the world’s population (24,069,943 at 2007).

Figure 1 Map of The Kingdom of Saudi Arabia with scale 1: 11,000,000
The input data were obtained from different sources. The map layers are available from the web site at . The map layers contain roads, neighbor countries, regions, big cities and oceans. The longitude, latitude and population of all cities are listed in the World Gazzeteer web site at https://world-gazetteer.com. The information of existing colleges was obtained from the General Organization for Technical Education And Vocational Training (GOTEVOT) web site at .

Uncertainty in data

1- The total population of Saudi Arabia is (24,069,943). After calculating the population in all cities that used in this project, both cities with existing colleges and the cities without colleges, the total population is almost 20,000,000. This means many locations with 4 million people were not located. The reason of this is that only the big cities, 154 cities, were located and there are hundreds of small cities and villages were not considered. As a result this may affect the final results.

2- The information of population may inaccurate as a result of errors when the data were collected.

3- Cities coordinates and population were collected manually from different sources. This is subject of human errors and may shift the cities locations or locate them incorrectly.

3- The methodology

The methodology for analysis of determining the best cities to be the places of new colleges requires digital map of the study area, the cities which have colleges and the others which do not have any college as input data. The input data is defined in points, lines, and polygons which represent city locations, roads and regions respectively. The input data were processed through a series of analysis operations in GIS to produce new polygons representing the boundary of the existing colleges, the population density and the best areas to be locations of new colleges. A flowchart of steps involved in analyzing the best place to build new colleges is shown in figure 2.

Figure 2 Flow chart of the methodology for determining the best locations to be future places of the new technical colleges.
The following steps are involved.

  1. The locations of the cities witch have a college of technology are located.
  2. The locations of the other cities are located also.
  3. Determining the distance to the closest college by using the Euclidean Distance in Arc GIS.
  4. By using the Kernel Density Tool the density of the population in the cities where are no colleges is processed.
  5. The best locations, where the new colleges should to be, have been identified using Map Algebra Tool.

The methodology is analyzed by analysis tools in ArcGIS, GISmap 9.2. A detailed description of each step is given in the following sections.

3.1 locating of the existing college

The name of the cities which contain colleges of technology is listed in the GOTEVOT web site. According to this web site the excel file is created containing of the name of the cities. Also the coordinate and population are added to this file by using world Gazzeteer web site. By using Display XY Data Toll the file is added to ArcGIS as a new layer in a shape file format. After the coordinates are displayed the coordinates system is sited to the world coordinate system WGS 1984. The new layer is represented as 31 pointes. Every point represents an existing college.

3.2 locating of the other cities

It is a challenge that the researcher can find any source of information that supplies him with the coordinates and population of the cities in Saudi Arabia in one table. However, the manual editing is used to collect the information about the coordinates and population of all cities. According to the World Gazzeteer web site, the new excel file is created. The file containing 154 cities distributed in all Saudi Arabia regions. The file also contains of the city’s coordinates and population. The file is added to ArcGIS in steps to make another new layer. The coordinates are displayed. Then the coordinate system is sited to the world coordinate system WGS 1984. The new layer is represented as 154 pointes. Every point represents a city where is no college.

3.3 The distances from the existing college.

In this step the Euclidean Distance Tool was employed to determine the distance from every existing college. As a result, a new digital layer with many colorful circles around every college was created. . As shown in figure 3 the yellow and orange colors indicate that the distance from the college is close. In contrast the purple and blue colors illustrate that the distance from the college is further away.

Figure 3 The distances to the existing college using Euclidean Distance Tool.

3.4 Population density

One of the most important steps in this project was determining of the population density. The Kernel Density in Spatial Analyst Tools used to determine the population density of the cities which do not have any college of technology. The method that used in classification was Standard Deviation. As illustrated in Figure 4 the dark blue means the high population areas.

Figure 4 The population density of the cities which do not have any college using the Kernel Density Tool in Spatial Analyst Tools in ArcMap.

3.4 What is the best place?

According to the data availability and returning to the question what is the best place to be a technical college, the two criteria that should be available in the new locations are:

1- highest in population density.
2- farthest away of the cities which have existing colleges.
The first method is to find areas that were the furthest away from the existing college, that were also in a high population density. The following query was done by using Map Algebra Tool in ArcMap.
([Distance to College]>1)&([Population Density]>175000) ArcMap identified two locations as shown in figure 5.

Figure 5 The best locations to be colleges of technology (Stage 1).

As a result of the limited number of location after implemented Map Algebra Tool using strict conditions in distance and population density, another query was implemented but with a lower strict condition. The distance to the existing college was reduced slightly to allow more location to be appearing. The condition of the high population density was still without any change .the Map Algebra Tool was used to identify the best location using the following equation. ([Distance to College]>0.5)&([Population Density]>175000) The number of locations in this case increased dramatically from two locations to be eight locations as shown in figure 6.

Figure 6 The best locations to be colleges of technology (Stage 1 and 2).


Figure 5 and figure 6 show the best locations that should be the future places of the new colleges. Figure 5 shows the two locations that will be the best to establish new colleges. The need of technical college is clear in the case of these two locations. If there is intention to build colleges in the future, the decision makers will be advised to give these locations priority over others. In addition, if there is need to build more than two colleges, figure 6 shows eight locations containing the former two locations. This leads to classify the result in two categories. The first category is Stage 1 containing two locations and Stage 2 containing six locations. The two tables below show these two stages.

Table 1 The best cities to be locations of the new colleges (Stage 1).

Table 2 The best cities to be locations of the new colleges (Stage 2).


This project has analyzed the locations of the best places to be colleges of technology in Saudi Arabia. A digital map has been used. The map contained many features such as regions, neighbor countries, roads, big cities and oceans. Two excel files have been created and added to Arc GIS. The first file contains 31 cities. Each city has a college of technology. The second file contained 154 cities where there are no existing colleges. Every city in the both files located with its longitude, latitude and population in 2007. In addition, data has been processed in a series of operations in ArcGIS ArcMap 9.2. The first procedure was identifying the distances to the existing colleges by using the Euclidean Distance Tool .The next procedure was determining the population density of the cities where is no existing college by using Kernel Density Tool. The last procedure was determining the best place by make queries in ArcMap using Map Algebra Tool depending on the two criteria should be in these places, the highest in population density and farthest away of the cities which have existing colleges. Therefore, it is obvious that there is need for more colleges especially in some areas which are far away from the country center. Also the need is still for more researches to locate if possible all cities and villages to reach the correct number of population. In addition, it is important to add more criteria to the population and the distances to the existing colleges.



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