A modular Geo Information System for archaeology and building history
Many projects of the German Archaeological Institute work in close cooperation with a multitude of international scholars and institutions, which are contributing to the same project from various locations. Our web-based modular information system CISAR was developed in order to give all cooperation partners easy access to the digital project databases. CISAR has been developed since 2004 and was planned from the beginning as a web-based database and GIS for the projects "Domus Severiana" on the Palatin in Rom of the University of Cottbus and the Architecture Department of the DAI, as well as for the Baalbek project of the Orient Department of the DAI. CISAR is now used by two additional projects and is continuously developed, in the future in cooperation with iDAI.field.
CISAR is a web-based Geo Information System for archaeology and building history applicable for different projects. Factual information on objects and materials are managed in a modular database, which distinguishes between basic modules and specific modules. The specific modules serve for the recording and analysis of finds and findings, building elements and buildings. To these objects photographs, plans, bibliographical references and other documents can be attached, which are administrated in the basic modules. In addition, as a Geo Information System the objects collected in CISAR can also be attached to 2D- or 3D geometrical data. While in the classical 2D and 2.5D domain the established Web-GIS methods are applied, for the visualization of complex building structures a 3D method on the basis of VRML has been developed. CISAR was developed by the Department of Geodesy of the University of Cottbus in cooperation with the project "Urban development in Baalbek” and the building historical project on the "Domus Severiana” on the Palatin in Rome. Meanwhile the system is also used for the "project on the settlement topography of Triphylia”, for the building and art historical "Project on the cathedral of Santiago de Compostela” and for the documentation of "Memorial landscape "Berlin Wall”.
In order to provide research groups working from different locations with access to a central uniformous database, CISAR was conceived and developed from the beginning as a web-based solution. The database systems are based on the classical client-server architecture and have several advantages over desktop systems:
Characteristic for CISAR is the modular system structure, which enables a flexible adaptation of project specific requirements. Through the cooperation of different scientific research projects for the modeling and development of the databases, specific modules for the recording and processing of archaeological and architectural finds and findings could be designed. In this respect a distinction has to be made between basic and specific modules, which are complemented by a query module and tools for the administration and organization.
In close consultation with the different architectural and archaeological research projects the factual data model in CISAR was upgraded to a flexible geometric data model for the recording of 2D and 2.5D-geometries. Together with the tools developed for the analysis and visualization of geometric data CISAR was thus upgraded into a complex Geo Information System. The GIS architecture has the following features:
For the analysis of complex, 3-dimensional building structures a web-based 3D-building information system was implemented on the bases of the spatial unit module in CISAR.
Standards for the modeling and visualization of 3D geometries on the internet are still lacking an adapted solution on the basis of the standardized VRML format was implemented. Thus objects in the spatial unit module can be attributed to 3D geometries. Query results can be visualized in 3D using a VRML-Viewer, and on the other hand in the 3D visualization factual data of different objects can be displayed.
The complete system architecture of CISAR, from the server as well as the client side was implemented using solely Open-Source Software. Thus CISAR is to a large extent independent from proprietary programs, and provides a maximum of flexibility and transparence.
The core of CISAR is a modular data model in a PostgreSQL-Database, which was enhanced with the help of PostGIS to provide the functions for saving and analysis of 2D- and 3D-geometrical data. The user interface through PHP using a special interface library ippfp was implemented consistently for all modules. As map server for the provision of geo-data the UMN MapServer is used, which supports different OGC-conform vector- and raster formats as well as standardized map services (WMS, WFS, GML, WMC).
Mapbender provides functions for the creation, display, navigation and query of different map providers for the UMN MapServer and thus acts as central interface between the geo data on the server and the WebGIS surface in the browser visible to the user. In addition to this standardized WebGIS solution a client application for the visualization of 2D-geometries based on Google-Maps API was implemented, while selected 3D-building geometries also can be displayed in 3 dimensions in the browser using a Google-Earth plug-in. For more extensive GIS-functions, especially for the modification and processing of geometrical data, the database content can directly be integrated into the desktop system Quantum-GIS. All server components are installed on the database/web server at the academic computing center of the University of Cottbus. The system is thus integrated into the automatic back-up routine and is professionally maintained and up-dated. For every one of the participating projects CISAR is installed on this server, based on the standardized data model and the same source code basis. This system concept guarantees a high availability and security of the centrally stored research data.
Dipl.-Ing. Frank Henze
Lehrstuhl für Vermessungskunde
Tel: +49 (0)355 69-2439
Fax: +49 (0)355 69-3490
The development of CISAR was funded to a large extent by the following institutions:
The Fritz Thyssen Foundation for the project of:
The German Archaeological Institue Berlin for the project of :
HENZE, F., LEHMANN, H., LANGER, W., 2008: CISAR - A Modular Database System as a Basis for Analysis and Documentation of Spatial Information. In: Posluchny, A., Lambers, K., Herzog, I. (eds.): Layers of Perception, Proceedings of the 35th International Conference on Computer Application and Quantitative Methods in Archaeology (CAA), Berlin, April 2-6, 2007. Dr. Rudolf Habelt GmbH Verlag (Bonn 2008), S. 228-233.
HENZE, F., 2008: A Distributed GIS Architecture for Research in Baalbek Based on CISAR. In: Posluchny, A., Lambers, K., Herzog, I. (eds.): Layers of Perception, Proceedings of the 35th International Conference on Computer Application and Quantitative Methods in Archaeology (CAA), Berlin, April 2-6, 2007. Dr. Rudolf Habelt GmbH Verlag (Bonn 2008), S. 234-240.
BRASSE, CH., HEINE, K., ZHAO, D., WULF, U., 2008: A 3D Solution for a Web-based Building Information System. In: Posluchny, A., Lambers, K., Herzog, I. (eds.): Layers of Perception, Proceedings of the 35th International Conference on Computer Application and Quantitative Methods in Archaeology (CAA), Berlin, April 2-6, 2007. Dr. Rudolf Habelt GmbH Verlag (Bonn 2008), S. 241, CD.