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| Geographic Information System |
In ArcView, geoprocessing is a way in which to create new spatial data based existing theme (s) in object view. In most cases (activity) with respect to this extension, users will alter the properties belonging geometric spatial elements while observing changes in the attribute data. The entire main functions in spatial analysis provided here follows its guide (wizard). Overlay maps and join spatial data which is a major force in spatial analysis can be easily understood and carried through this tool. Learn more operations that can be performed spatial extension Geoprocessing is:
1. Dissolve: This process will basically unify or eliminate the boundaries of spatial elements right next to each other but located in a same theme or in other words dissolve an operation that used to unite the features that have the same attribute values.
2. Union: This process will produce a new theme by combining two themes. Output generated theme is a combination of these two features, the following attributes of the data.
3. Merge: This process is similar to the union will produce a new theme that is a combination of several themes that are side by side, but the spatial elements do not intersect. Data attributes of each theme will automatically be incorporated.
4. Clip: Basically this work is "cut" or cutting out a theme. This process generates a new theme by theme in accordance with the type of object being cut (point, line, and polygon). therefore, the new theme will only contain spatial elements of theme objects contained within the cutter theme.
5. Intersect: The process is basically not much different from the clipping but the intersect, a new theme is the second slice of spatial data themes that become inputs to the theme overlay as its boundaries intersect.
Buffering is one of the processes in the geoprocessing commonly used in GIS analysis. Buffer or widening / buffer is an area that includes the features (points, lines, or polygons) with a certain distance. Buffers are usually used to represent a range of services or an area that is assumed to be a certain distance to an interest in the spatial analysis. Buffer can be done fatherly type feature polygon, polyline and point.
Making the buffer requires a determination of the distance measured in units (meters or kilometers.) Buffer operation is very important to determine the area of influence of the feature. Buffer will describe a circular region around the point or corridor around the line and the wider region around the polygon. By creating a buffer, it will form an area, polygon, or a new zone that covers (or cover) spatial objects (buffered object) in the form of objects points, lines or areas (specific polygon) with a certain distance.
Purpose
1. Identify areas that are around the appearance of geographical
2. provide a close approximation of the size of an appearance
Basic theory
Geographic Information System (GIS) is a computer-based information system, which is used for processing the georeferenced spatial data (in the form of details, facts, conditions, etc.) are stored in a database and is associated with problems as well as the state of the real world (real world). GIS benefits generally provide information closer to real world conditions, predict an outcome and strategic planning.
In GIS, there are various roles of the various elements, both human as well as experts and operators, device tool (software / hardware) and the object of the problems. GIS is a system circuit that utilizes digital technology to perform spatial analysis. The system utilizes hardware and computer software to perform data processing such as:
1. Acquisition and verification.
2. Compilation.
3. Storage
4. Updates and changes.
5. Management and exchange.
6. Manipulation.
7. presentation
8. Analysis.
(Tor Bernhardsen, 1992 in Budiyanto, 1992).
Geoprocessing is a set of functions that perform operations on the basis of the geographical location of the input layers.
There are 6 menus in geoprocessing that is:
1. Dissolve
2. Merge
3. Clip
4. Intersect
5. Union
These geoprocessing functions are often also used as a complement of the function Buffer. Buffer describe a closed area (polygon) at a certain distance in a certain appearance of the landscape. Can choose a buffer that has been formed for example:
1. Only area outside the polygons in the buffer
2. Regions outside the polygon plus other polygon area
3. Buffer area formed inside and outside the polygon in coverage
How it Works Buffer
1. Buffer processing mathematical algorithms to identify spaces that are around the landscape appearance
2. Appearance chosen for buffering must go through several selection processes and considerations
3. Distance buffers can come from direct input, from the attributes and other data
4. A line can be drawn in many directions around the selected area to form a solid polygon
5. A new data base containing data on the buffer generated after completion buffer polygons are formed.
Methods
Tools and Materials
1. A set of computer or laptop that is compatible with ArcView GIS 3.3
2. Software ArcView 3.3 GIS
3. The data files are:
a) Rumah_sakit.dbf
Rumah_sakit.sbn
Rumah_sakit.sbx
Rumah_sakit.shp
Rumah_sakit.shx
b) Sungai_ciliwung.dbf
Sungai_ciliwung.sbn
Sungai_ciliwung.sbx
Sungai_ciliwung.shp
Sungai_ciliwung.shx
4. Mouse
5. The external keyboard (if needed)