CROATIAN CADASTRE DATABASE MODELING
Z. Biljecki *, H. Halapija *, D. Piskor *, A. Osmanagié *, D. Vencler *, V. Topolovec ^
* GEOFOTO LLC, Hercegovacka 61, 10 000 Zagreb, Croatia — (zvonko, hrvoje, drazen, aida, daniel)@geofoto.hr
? Filozofski fakultet Rijeka, 51 000 Rijeka, Croatia — velimir.topolovecl @zg.tel.hr
Commission VI, WG VI/3
KEY WORDS: Cadastre Data Model, conceptual modeling, ISO, OpenGIS, GI, UML application schema, XML/GML schema,
KaMP schema
ABSTRACT:
The Cadastral Data Model has been developed as part of a larger programme to improve the products and production environment of
the Croatian Cadastral Service of the State Geodetic Administration. The goal of the project was to create the cadastral data model
conforming with relevant norms and specifications in the field of geoinformation (GI) adapted by international organisations for
standardisation under the competence of GI (ISO TC211 and OpenGIS) and it implementations.
The main guidelines during the Project have been the object-oriented conceptual modeling of the updated users’ requests and a
“new” cadastral data model designed by SGA - Geodetic Faculty - Geofoto L.L.C. project team. The UML of the conceptual model
is given per all feature category and it is described at class level only. The next step has been UML technical model which was
developed from the UML conceptual model. The technical model integrates the different UML schemas in one overall schema.
XML (eXtensible Markup Language) was applied for XML description of UML models, than XML schema was transferred into
GML (Geography Markup Language) application schema. With this procedure we have completely described the behaviour of each
cadastral feature and rules for the transfer and storage of cadastral features into database.
1. INTRODUCTION " an object, as the principal database element;
" set of operations that can be performed with the
The basic principle of the Project is object-oriented conceptual objects;
modeling and designing in the function of producing the " set of general data integrity rules that define
cadastre data base. Cadastre data model meets the conditions of implicitly of explicitly, the set of consistent states of
graphic and alphanumeric modeling in accordance with the data or the changes of states.
defined cadastre contents taking the standards ISO
(International Standard Organisation) TC 211 (Technical
Committee) and OGC (OpenGIS Consortium) in the filed of
geoinformation. The Project of cadastre data model
encompasses the modeling of users’ requests in accordance
Modeling
with the world trends, which helped us to obtain the basis for Data span Abstraction
the establishment of cadastral information system. v v
The basic guideline in modeling the cadastral system is the fact
that one should process, present and maintain the geometric and m coitants ui stracure Applic
alphanumeric spatial data contained in the cadastre database in Datibasc € ation
accordance with the economic needs, the users’ demands, and schema
the standards within the frame of the world geoinformation ISO
organisation, OpenGIS Consortium, and professional and legal
regulations in the field of topographic, cartographic, and Figure 1. Data modeling
cadastral information systems. Object-oriented modeling raises
the level of quality and usage value of the data respecting the ISO 19109
principals of conceptual modeling.
/ XMl doc of simple XMI dec
2. CONCEPTUAL MODELING UML Model Of UML Model
Conceptual modeling is based on the usage of abstractions, i.e
Y
similarities between real world objects and temporary UML Le
neglecting of the differences between them. The real world
on the modeling methodology based on the recognition of
model, objects and connections between them are decomposed Doumem / 7 XMLto GML schema
by means of the abstraction into the hierarchy of abstractions, Data transfer »
Le. the combination of aggregations and generalisations. Process (e
The data model is a phase in establishing information systems.
Based on the definition itself, the data model has to be outlined Figure 2. MDA modeling approach
in such a way that it enables an efficient approach to data, as
well as to make adequate operations with the data possible. The
data model as a formal system must contain the following
components:
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