Quantum Logic Based MPEG Query Format Algebra.
ABSTRACT The need for fast processing of query requests in multimedia retrieval systems is apparent. One basis for optimization is the formalization of the corresponding query language by a respective algebra. Furthermore, an algebra is important for demonstrating the profoundness and validity of a query language. In this context, the article contributes a formal semantics model for the novel standardized MPEG Query Format for multimedia search. In addition to the specification of its syntax and semantics, our quantum logic approach for fuzzy retrieval on behalf of the formal model is discussed. Besides the validity of our formalization is demonstrated on some examples, the advantages as well as the shortcomings of the query format are discussed.
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ABSTRACT: Traditional database query languages are based on set theory and crisp logic. Many applications, however, need similarity or retrieval-like queries producing results with truth values from the interval [0,1]. Such truth values can be regarded as continuous membership values of tuples expressing how strongly a query is matched. Formulating queries by applying existing similarity relational algebras means to express the user’s need in a procedural manner. In order to support a declarative way of formulating queries, we generalize the classical relational domain calculus by incorporating fuzzy operations and user weights. Besides defining syntax and semantics we show how to map any calculus expression onto a corresponding similarity algebra expression. In this way, we present a theoretical foundation for a declarative query language combining retrieval functionality and traditional relational databases.Foundations of Information and Knowledge Systems, Third International Symposium, FoIKS 2004, Wilhelminenberg Castle, Austria, February 17-20, 2004, Proceedings; 01/2004
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ABSTRACT: A “scoring rule” is an assignment of a value to every tuple (of varying sizes). This paper is concerned with the issue of how to modify a scoring rule to apply to the case where weights are assigned to the importance of each argument. We give an explicit formula for incorporating weights that can be applied no matter what the underlying scoring rule is. The formula is surprisingly simple, in that it involves far fewer terms than one might have guessed. It has three further desirable properties. The first desirable property is that when all of the weights are equal, then the result is obtained by simply using the underlying scoring rule. Intuitively, this says that when all of the weights are equal, then this is the same as considering the unweighted case. The second desirable property is that if a particular argument has zero weight, then that argument can be dropped without affecting the value of the result. The third desirable property is that the value of the result is a continuous function of the weights. We show that if these three desirable properties hold, then under one additional assumption (a type of local linearity), our formula gives the unique possible answer.Theoretical Computer Science. 01/2000;
Conference Paper: Full-fledged algebraic XPath processing in Natix[Show abstract] [Hide abstract]
ABSTRACT: We present the first complete translation of XPath into an algebra, paving the way for a comprehensive, state-of-the-art XPath (and later on, XQuery) compiler based on algebraic optimization techniques. Our translation includes all XPath features such as nested expressions, position-based predicates and node-set functions. The translated algebraic expressions can be executed using the proven, scalable, iterator-based approach, as we demonstrate in form of a corresponding physical algebra in our native XML DBMS Natix. A first glance at performance results shows that even without further optimization of the expressions, we provide a competitive evaluation technique for XPath queries.Data Engineering, 2005. ICDE 2005. Proceedings. 21st International Conference on; 05/2005