Abstract
In this paper we introduce Degas (Dynamic Entities Get Autonomous Status), an active temporal data model based on autonomous objects. The active dimension of Degas means that we define the behaviour of objects in terms of production rules. The temporal dimension means that the history of an object is included in the Degas data model. Novel features of Degas axe the encapsulation of the complete behaviour of an object, both potential and actual. Thus, Degas combines dynamic and structural specifications in one model. In addition, Degas allows easy evolution of object capabilities through a clear distinction between inherent types and capabilities that can be acquired and lost. This addon mechanism makes Degas very suitable as a formalism for role modelling. Finally, the rule model in Degas is both simple, through the use of finite automata, and general, because it allows different strategies for dealing with constraints and reacting to events in other objects.
Keywords
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This research is supported by SION, the Foundation for Computer Science Research in the Netherlands through Project no. 612-323-424
Download to read the full chapter text
Chapter PDF
Similar content being viewed by others
References
Special issue on intelligent agents. Communications of the ACM, 37(7), July 1994.
J.F.P. van den Akker and A.P.J.M. Siebes. A data model for autonomous objects. Technical Report CS-R9539, CWI, Centre for Mathematics and Computer Science, Amsterdam, The Netherlands, 1995. Available through WWW (http://www.cwi.nl/∼vdakker/Publications.html).
J.F.P. van den Akker and A.P.J.M. Siebes. Degas: A temporal active data model based on object autonomy. Technical Report CS-R9608, CWI, Amsterdam, The Netherlands, 1996. Available through WWW (http://www.cwi.nl/∼vdakker/Publications.html).
A. Albano, R. Bergamini, G. Ghelli, and R. Orsini. An object data model with roles. In Rakesh Agrawal, Sean Baker, and David Bell, editors, Proc. of the 19th Intl. Conf. on Very Large Data Bases (VLDB), Dublin, Ireland, 1993.
J.C.M. Baeten and W.P. Weijland. Process Algebra. Number 18 in Cambridge Tracts in Theoretical Computer Science. Cambridge University Press, Cambridge, UK, 1990.
Herman Balsters and Maarten M. Fokkinga. Subtyping can have a simple semantics. Theoretical Computer Science, 87:81–96, 1991.
Luca Cardelli. A semantics of multiple inheritance. In G. Kahn, D.B. MacQueen, and G. Plotkin, editors, Proceedings of the International Symposium on the Semantics of Data Types, pages 51–68, Berlin, Germany, 1984. Springer.
Stefano Ceri and Rainer Manthey. Consolidated specification of Chimera (CM and CL). Technical Report IDEA.DE.2P.006.01, IDEA, ESPRIT Project 6333, 1993. Available by FTP from rodin.inria.fr:/pub/IDEA/DE.2P.006.ps.gz.
U. Dayal et al.. The HiPAC project: Combining active databases and timing constraints. SIGMOD Record, 17(1):51–70, March 1988.
Klaus R. Dittrich and Stella Gatziu. Time issues in active database systems. In N. Pissinou, R.T. Snodgrass, and R. Elmasri, editors, Towards an Infrastructure for Temporal Databases: report of an international ARPA/NSF workshop, Tucson, AZ, USA, 1994. University of Arizona, Dept of Computer Science, TR 94/01.
Klaus R. Dittrich, Stella Gatziu, and Andreas Geppert. The active database management system manifesto: A rulebase of ADBMS features. In T. Sellis, editor, Rules in Databases: Proc. of the 2nd International Workshop, pages 3–17, Berlin, Germany, 1995. Springer.
Stella Gatziu, Andreas Geppert, and Klaus R. Dittrich. Integrating active concepts into an object-oriented database system. In Paris Kanellakis and Joachim W. Schmidt, editors, The Third International Workshop on Database Programming Languages: Bulk Types and Persistent Data, pages 399–415, San Mateo., CA, USA, August 1991. Morgan Kaufmann.
David McAllester and Ramin Zabih. Boolean classes. In M. Meyrowitz, editor, Proceedings OOPSLA '86, pages 417–423, 1986.
L. Edwin McKenzie Jr. and Richard T. Snodgrass. Evaluation of relational algebras incorporating the time dimension in databases. ACM Computing Surveys, 23(4):501–543, December 1991.
G.M. Nijssen and T.A. Halpin. Conceptual schema and relational database design: a fact oriented approach. Prentice-Hall, New York, USA, third edition, 1990.
Joel Richardson and Peter Schwarz. Aspects: Extending objects to support multiple, independent roles. In Proceedings of the ACM SIGMOD International Conference on the Management of Data, pages 298–307, 1991.
Yoav Shoham. Agent-oriented programming. Artificial Intelligence, 60:51–92, 1993.
A.P.J.M. Siebes, J.F.P. van den Akker, and M.H. van der Voort. (undecidability results for trigger design theories. Technical Report CS-R9556, CWI, Amsterdam, The Netherlands, 1995. Available through WWW (http://www.cwi.nl/∼vdakker/Publications.html).
A. Prasad Sistla and Ouri Wolfson. Temporal conditions and integrity constraints in active databases. In Proc. of the 1995 SIGMOD International Conference on the Management of Data, pages 269–280, San Jose, CA, USA, 1995.
A.U. Tansel, J. Clifford, S. Gadia, S. Jajodia, A. Segev, and R. Snodgrass. Temporal Databases: Theory, Design, and Implementation. Benjamin/Cummings, Redwood City, CA, USA, 1993.
Jennifer Widom and Stefano Ceri. Active Database Systems: Triggers and Rules for Advanced Database Processing. Morgan Kaufmann, San Francisco, CA, USA, 1995.
Roel Wieringa, Wiebren de Jonge, and Paul Spruit. Using dynamic classes and role classes to model object migration. Theory and Practice of Object Systems, 1(1):61–83, 1995.
Eric Yu, Philippe Du Bois, Eric Dubois, and John Mylopoulos. From organization models to system requirements: A “cooperating agents” approach. In Proc. of the Third International Conference on Cooperative Information Systems (CoopIS'95), Wien, Austria, May 1995.
Author information
Authors and Affiliations
Editor information
Rights and permissions
Copyright information
© 1996 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
van den Akker, J., Siebes, A. (1996). DEGAS: Capturing dynamics in objects. In: Constantopoulos, P., Mylopoulos, J., Vassiliou, Y. (eds) Advanced Information Systems Engineering. CAiSE 1996. Lecture Notes in Computer Science, vol 1080. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-61292-0_5
Download citation
DOI: https://doi.org/10.1007/3-540-61292-0_5
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-61292-6
Online ISBN: 978-3-540-68451-0
eBook Packages: Springer Book Archive