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Land Information Systems for muncipal planning
Approaches to the introduction of lis in municipal planning:
Which strategies can be utilized in the introduction of land information systems in planning departments ? It is a well known fact that a transition from traditional to computer based operations involves major financial, organizational and personal consequences. Moreover, it may well take up to few years before information planning becomes a fully operational aspects: the flow of information and the employment of systems. Theoretically, an organization has to make two initial choices :
Let us examine the two models discussed above (Fig. 3 & Fig. 4). The creation of databases for planning departments can be based on the central graphical and alphanumerical databases maintained by the technical and administrative departments. Extensive data processing is required to transform the information to the necessary format. Additionally, information must be gathered and entered into the system. A first step is joining the graphical and alphanumerical data forming a common geo-coding and identification system. The existence of uniform classification and geocoding procedures is essential to be able to link the databases. This means that the records in administrative databases have to be linked to objects in the graphical databases. Street sections, parcel numbers, blocks, wards, transportation networks, etc. are often the geographical units that are used in planning base maps. Further the graphical data have to be generalized to the preferred map scale and, when necessary, converted to the required LIS data structure. The alphanumeric data have to be aggregated to the geographical units used in planning. The joining of two databases can be done either before or after the generalization and aggregation procedures. When all data manipulation procedures have been successfully completed, advanced information processing and mapping become feasible. The second approach is initiated within the planning department itself. Based on a small PC, existing paper maps can be digitized / scanned and available statistical databases can be connected to these map files. The map files will most likely be a combination of point, line segment and boundary files. This approach will result in a planning information system for a municipality that is useful for many queries and thematic mapping applications. It can be expected, however, that after some time a need for a larger scale system and advanced applications might arise. The possibilities for advanced LIS applications on PC's will grow considerably in the next few years, although a decision to migrate to a LIS based system on a workstation may be unavoidable. In order to preserve the information in existing databases, data conversion would be necessary. The number of graphical and alphanumerical exchange standards, conversion programmes and data restructuring tools have increased considerably. So, the fear of complete loss of data is no longer justified. 
In both cases, a LIS will be constructed consisting of one or more digital planning maps and statistical data as attributes of map objects. This database has to be supplemented with data from other information sources. Ideally, information in policy documents should be stored in the planning information system as well. A LIS based planning information system has to be employed for the support of the main activities of a planning department. Four types of applications seem particularly well suited for computer support.
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