Database Management System (DBMS)

AGISwlk data is stored in a geodatabase data model which taking the advantage of DBMS. Hence, strengthen the whole data structure. AGISwlk uses Microsoft SQL Server 2000 as its DBMS due to its dynamic feature as well as its highly efficient storage, searching and modeling mechanism that can serve many users simultaneously. The DBMS software however, only stores data in table form. Therefore, users need another tool that allow them to access the data which is ArcSDE. ArcSDE is the tool that allows user to store data in DBMS software and to use the data in GIS applications. It acts as a gateway to relational database which allowing user to manage geographic information in any DBMS software.

GIS software

AGISwlk users need certain GIS software in order to allow them to interact with the data. The main software used is ArcGIS ArcInfo and ArcGIS ArcView. These software enable user to manipulate the data via 3 applications: ArcCatalog, ArcMap and ArcToolbox. AGISwlk also have web-based GIS through ArcIMS 4.0. The web-based GIS allows public and stakeholders to view data from the website http://www.kwp.gov.my/AGISwlkweb

Element and Data Layers

AGISwlk data comprises of 25 elements of data. In each of these elements are layers that have common spatial reference. There are over 90 layers of data that has been grouped into these elements. The layers comprises of point, line and polygon feature. For example, transportation element have 4 layers in them. These layers are road line (line features), junction (point feature), rail line (line feature) and station (point feature).

Spatial Reference

The earth-based coordinate system in which the dataset is represented. This specifies the dataset’s real-world location. It includes properties such as the map projection, the datum, the allowable range for the coordinates and so on. AGISwlk data is stored in Rectified Skewed Ortomorphic (RSO) projection as its spatial reference. However, the data can be converted to Cassini or other projection

Image

AGISwlk data also consists of image that are used as guidance for database development. There are 2 types of image that has been used: IKONOS image and Landsat-TM image. This images are obtained from MACRES. IKONOS image is a satellite image that have 3 bands RGB with 1 meter resolution. On the other hand, Landsat-TM image is a multispectral satellite image that have 30m x 30m spatial resolution. The image is obtained every 2 years. The image data can provide brief illustration on land use changes occurred between the years. This images are stored in raster dataset for the whole Klang Valley. AGISwlk also have aerial photographic image that covers Kuala Lumpur Town Council for year 1997.

 

Digital Terrain Model (DTM)

DTM is generated from contour lines at 1:25,000 and 1:50,000 input scales. It is stored in TIN dataset for the whole Klang Valley.