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CIKM '94 Proceedings of the third international conference on Information and knowledge management
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ACM Transactions on Database Systems (TODS)
Supporting valid-time indeterminacy
ACM Transactions on Database Systems (TODS)
Handling infinite temporal data
PODS '90 Proceedings of the ninth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
The Management of Probabilistic Data
IEEE Transactions on Knowledge and Data Engineering
Representation and Querying in Temporal Databases: the Power of Temporal Constraints
Proceedings of the Ninth International Conference on Data Engineering
Querying Continuous Time Sequences
VLDB '98 Proceedings of the 24rd International Conference on Very Large Data Bases
A Conceptual Development Framework for Temporal Information Systems
ER '97 Proceedings of the 16th International Conference on Conceptual Modeling
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Current information systems model enterprises that are crisp. A crisp enterprise is defined as one that is highly quantifiable; all relationships are fixed, and all attributes are atomic valued. This paper is based on precise enterprises, where data are imperfect and where multiple and possibly conflicting sources of information do exist. Imperfection may be related to the actual values or the time that something happened within an organisation. In such domains different sources of information may be assigned different degrees of reliability. Factual imperfection and/or temporal indeterminacy may cause uncertainty. Temporal information may be recurring, periodical or definite. This paper is presenting a conceptual and algebraic framework for a uniform treatment and representation of all these types of information.