Geographic Information System LITERATURE REVIEW

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2.5. Geographic Information System

Geographic Information System is a set of hardware, software, geographic data and people, designed efficiently for collecting, storing, updating, manipulating, analyzing, and presenting for all information geographic referenced [ESRI, 1995]. Geographic information System is a general purpose tool, contain several maps illustrating a few of the many GIS application. Figure 2. Several Component Comprise a GIS [SEAMEO BIOTROP, 2004] Geographic Information System is information system to manage data that has spatial information. In specific term, the GIS is computer system that has the ability to build, restore, manage, and to display the information based on geographically, such as the data that identified based on location in a database, the user who involves building and operating is part of this system. Basically the entry data process shown in the following figure: [SEAMEO BIOTROP, 2004]. Abstraction or Simplification GIS Software tools Database The Real World User Result 20 Figure 3. GIS Process [SEAMEO BIOTROP, 2004] As articulated by Bruce [1996], spatial data as data that occupies cartographic map able space and that usually has specific location according to some geographic referencing system e.g., Latitude-Longitude or address. Spatial data are data defined by physical characteristics, usually including location or position. Spatial data may simply give an address a specific location, or they can define size, such as a certain area of a forest which is the same as defining the various positions of boundaries. The illustration shows a database containing addresses and a map lower left showing the area. Both the database and map represent spatial data. The addresses in the database are locational, and are therefore considered spatial data. The map is based on location, so it, too, is spatial. The owner name and value of the property are non-spatial data. They are descriptive characteristics called attribute . Many attributes are not location-specific but are mean to offer description about the spatial data or something that occurs at the location. For examples, Mr. X is the owner of one address, but he couldn t own, or move to, 21 another address. The address doesn t change, but the attribute owner might. GIS data set usually contains spatial data and associated non-spatial data. GIS data comes from a variety of sources: digitization of maps electronic copying, tabular data such as census lists, remote sensing imagery, user input typed-in data, existing reports e.g., soil surveys, and digital products e.g., digital line graphs sold in some countries. These diverse sets of data upper illustration are not naturally combined. It is difficult to hold up a satellite image, for instance, and compare it to a list of agricultural sites, they do not integrate easily. All these data sets must go somewhere for GIS use, and that place is the database a program that stores and manages data. The database contains data and may point to other data sets, such as satellite imagery. A major strength of GIS is that it can accept and merge diverse data into a single database, giving the user a flexible and powerful set of data from which to work. Database in GIS is a simple concept a list or table of data arranged as columns categories of data and rows each observation entry. Columns are called fields , whereas rows are records . 22

III. METHODOLOGY

3.1. Time and Location

This study was conducted from January - September 2006, in Desa Nagrak, Gunungputri Sub District, Bogor District, West Java Indonesia. The coordinate location in TM-3 zone 48.2 datum WGS-84 is A 251,592.00 ; 781, 915.14, B 250,121.85 ; 792,001.88, C 248,331.51 ; 792,081.46, D 247,183.42 ; 793,519.41, E 248,581.59 ; 795,542.77. 1 Data analysis was carried out at the MIT Master of Science in Information Technology Program, Bogor Agricultural University IPB, SEAMEO-BIOTROP. Figure 4. Study Area Source : Kantor Pertanahan Kab. Bogor, 2002 1 The coordinate location in geographic coordinate datum WGS-84 is A 106 59 49.9176 ; -6 22 36.2460 , B 106 57 11.1600 ; -6 24 11.1312 , C 106 56 12.894 ; -6 24 8.5932 , D 106 55 35.4936 ; -6 23 21.8112 , E 106 56 20.9364 ; -6 22 15.8988 . Bogor District Study Area Desa Nagrak, Gunungputri Sub District, Bogor District West Java, Indonesia A B C D E