Alexander Brodsky

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The purpose of good database logical design is to eliminate data redundancy and isertion and deletion anomalies. In order to achieve this objective for temporal databases, the notions of <italic>temporal types</italic>, which formalize time granularities, and <italic>temporal functional dependencies</italic> (TFDs) are intrduced. A temporal type is a(More)
ÐThis paper investigates the problem of inference channels that occur when database constraints are combined with nonsensitive data to obtain sensitive information. We present an integrated security mechanism, called the Disclosure Monitor, which guarantees data confidentiality by extending the standard mandatory access control mechanism with a Disclosure(More)
Datalog (i.e., function-free logic) programs with monotonicity constraints on extensional predicates are considered. A monotonicity constraint states that one argument of a predicate is always less than another argument, according to some partial order. Relations of an extensional database are required to satisfy the monotonicity constraints imposed on(More)
This paper proposes a framework for Composite Alternative Recommendation Development (CARD), which supports composite product and service definitions, top-k decision optimization, and dynamic preference learning. Composite services are characterized by a set of sub-services, which, in turn, can be composite or atomic. Each atomic and composite service is(More)
Constraints provide a flexible and uniform way to represent diverse data capturing spatio-temporal behavior, complex modeling requirements, partial and incomplete information etc, and have been used in a wide variety of application domains. Constraint databases have recently emerged to deeply integrate data captured by constraints in databases. This paper(More)
This paper describes an access control model, called BARAC, that is based on balancing risks of information disclosure with benefits of information sharing. The model configuration associates risk and benefit vectors with every read and update transaction. An allowed transactions graph captures allowed transactions and flow paths that can be used to carry(More)