8,759 research outputs found

    Towards Intelligent Databases

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    This article is a presentation of the objectives and techniques of deductive databases. The deductive approach to databases aims at extending with intensional definitions other database paradigms that describe applications extensionaUy. We first show how constructive specifications can be expressed with deduction rules, and how normative conditions can be defined using integrity constraints. We outline the principles of bottom-up and top-down query answering procedures and present the techniques used for integrity checking. We then argue that it is often desirable to manage with a database system not only database applications, but also specifications of system components. We present such meta-level specifications and discuss their advantages over conventional approaches

    Some notes on an extended query language for FSM

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    FSM is a database model that has been recently proposed by the authors. FSM uses basic concepts of classification, generalization, aggregation and association that are commonly used in semantic modelling and supports the fuzziness of real-world at attribute, entity, class and relations intra and inter-classes levels. Hence, it provides tools to formalize and conceptualize real-world within a manner adapted to human perception of and reasoning about this real-word. In this paper we briefly review basic concepts of FSM and provide some notes on an extended query language adapted to it.ou

    An object-oriented model of measurement systems

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    This paper presents a general object-oriented model for measurement systems. The limitations of the conventional function-oriented models are examined in the light of the generalized concept of measurement and its theoretical framework proposed previously by the authors. The proposed model identifies five classes of objects, i.e., measured object, measuring instrument, reference standard, human observer, and operating environment. Each is characterized by its own attributes and operations or functions at three levels, i.e., internal, operational, and environmental. The interactions between them are also modeled, including the coupling between the measured object and the measuring instrument, the human-instrument interface, the calibration, and the interference. It serves as both a modeling framework and a practical tool for description, analysis and design, and, in particular, for computer-aided analysis and design of a measuring system. It will find applications in instrumentation engineering and measurement research and education
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