CI PA 2003 XIX th International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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Subsequently to this conceptual modelling process there 
follows the system choice, in which the used computer systems 
and programs are selected, for example the GIS or the database 
system. The system choice depends on application and the 
conceptual model. 
For Implementation a logical model is developed from the 
conceptual model considering the characteristics of the selected 
computer programs and database system. 
3.2.1 Conceptual model with UML 
The current quasi-standard UML for the diagram of conceptual 
data model was used to stay abreast of the object-oriented 
extensions. UML stands for Unified Modelling Language and 
offers different features during the object oriented design of 
application. In the illustration in Figure 4 only class diagrams 
have been used. Further possibilities of UML are e.g. use case 
diagrams or features to represent dynamic aspects of object 
behaviour (Booch et al, 1998). 
UML class diagrams mainly consist of single classes with their 
attributes and methods. 
In Figure 4 a clearly simplified fragment from the UML class 
diagram of the data model for a temporal GIS is shown. Here 
was considered that an object of application can have thematic, 
spatial as well as differentiated temporal characteristics. 
Figure 4. Fragment of the UML class diagram 
Several classes have relationships. For example there is a 1 to n 
relationship between the classes DATA OBJECT and MAIN. 
Aggregation and composition are special kinds of relationships. 
The aggregation ( -o ) expresses only a “ is part of’ - 
relationship. That means that an object can exists of other 
objects, however without bringing in additional semantics 
restricting the object. 
The composition ( —) restricts the object and its com 
ponents in such form that an individual component of the 
object, which participates in this composition may not exist 
alone. 
3.2.2 Implementation in Oracle 8i 
The data model was implemented into the object-relational 
database management system Oracle 8i. Therefor in the 
conceptual model it was already considered that no sufficient 
means of inheritance have been available and so a hierarchical 
structure was simulated by the use of the table MAIN as a super 
object. 
The class TIME offers the possibility to differentiate as well as 
to combine points and periods of time with different accuracy. 
For example the storage could be made as a snapshot or as a 
development over larger periods. 
The time was modelled in such way, that the limits of an 
interval of time can be unknown or can determined as 
intentionally open, e.g. if a development has not finished. 
In addition different advanced thematic data has to be 
provided in the several classes of DATA OBJECT, e.g. content 
of the official monument list, which is associated to the object 
or specialised information for certain target groups. 
Vector geometries are stored in the data model on a data type 
GEOMETRY, which is present in Oracle 8i in connection with 
the spatial cartridge. With the help of this data type the 
connection is made between the database model and a GIS. The 
column ID stores, like the table MAIN, a generic ID, which 
represents a simple possibility of accessing single spatial 
objects without to produce complete spatial inquiries. This is 
particularly helpful regarding the production of references in 
the Nested Table TABLE(MAIN. GEOM_REF). The storage of 
instances of the class SPATIOJTYP takes place in the object 
table GEOMETRY. Especially newer GIS of the large 
manufacturers in the geo information market enables the direct 
access to the Oracle data type SDOjGEOMETRY for the 
storage of spatial information in the database. Thereby it is also 
ensured that the data model can be used in different GIS 
systems. 
4. REALISATION AND GIS-TECHNOLOGY 
The structural differences between spatial and non-spatial 
information led in the past to a separate data management. The 
dual organisational structure was gradually given up in the last 
decade in favour of an integrated data management. 
In this context geo information systems have been developed, 
which store spatial data not in the form of files but in databases. 
The implementation of such information systems was realised 
with special external database extensions, which are also known 
as "GIS middleware". 
This development has promoted and certainly initiated the 
spreading of a new generation of database systems: Now 
geographical database systems can be regarded as relational 
database systems with object-oriented extensions and have 
internal auxiliary modules for the access to georeferenced data. 
Examples of these auxiliary modules are "Oracle Spatial", "IBM 
Spatial Extender" and the "Informix Spatial DATA Blade". 
These software products enable an integrated data management 
of spatial and non-spatial data and offer uniform (however 
usually manufacturer-specific) database interfaces - the supplied 
possibilities offer thereby certain basic functionality for 
complex geo information systems. 
4.1 Architecture 
The prototypic GIS solution at Techn. University of Munich is 
based on an object-relational alphanumerical data model 
implemented in the database system Oracle and the storage of 
the spatial data with the spatial data engine (SDE) of ESRI. 
For the input of the alphanumerical data and pictures an input 
module was developed on the basis of Oracle Objects for OLE 
(Visual basic). For inquiry and visualisation of historically 
interesting geometric and alphanumerical data a platform 
independent request module (see 
Figure 5) on basis of Oracle Extensions for JDBC (Java) was 
developed.