5,058 research outputs found

    Issues and Guidelines in Modeling Decomposition of Minimum Participation in Entity-Relationship Diagrams

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    The entity-relationship model has long been employed for conceptual modeling of databases. Methodologies and heuristics have been developed, both for effective modeling and for translating entity-relationship models into relational models. One aspect of modeling that is often overlooked in design methodologies is the use of optional versus mandatory participation (i.e., minimum participation) on the development of relational databases. This tutorial complements existing instructional material on database design by analyzing the syntactic implications of minimum participation in binary, unary, and n-ary relationship sets and for the special case where the E-R diagram depicts a database where 3NF is not in BCNF. It then presents design modeling guidelines which demonstrate that (1) for binary 1:1 and 1:M relationship sets, the presence of optional participation sometimes means that the relationship set should be represented in the relational model by a separate relation, (2) unary relationship sets cannot have a (1,1) participation, (3) n-ary relationship sets that have a (1,1) participation can be simplified to be of lower connectivity, and (4) decomposition is not a substitute for normalization. Illustrative examples and modeling guidelines are provided

    Securing Databases from Probabilistic Inference

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    Databases can leak confidential information when users combine query results with probabilistic data dependencies and prior knowledge. Current research offers mechanisms that either handle a limited class of dependencies or lack tractable enforcement algorithms. We propose a foundation for Database Inference Control based on ProbLog, a probabilistic logic programming language. We leverage this foundation to develop Angerona, a provably secure enforcement mechanism that prevents information leakage in the presence of probabilistic dependencies. We then provide a tractable inference algorithm for a practically relevant fragment of ProbLog. We empirically evaluate Angerona's performance showing that it scales to relevant security-critical problems.Comment: A short version of this paper has been accepted at the 30th IEEE Computer Security Foundations Symposium (CSF 2017

    The use of artificial intelligence techniques to improve the multiple payload integration process

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    A maximum return of science and products with a minimum expenditure of time and resources is a major goal of mission payload integration. A critical component then, in successful mission payload integration is the acquisition and analysis of experiment requirements from the principal investigator and payload element developer teams. One effort to use artificial intelligence techniques to improve the acquisition and analysis of experiment requirements within the payload integration process is described

    Causality and the semantics of provenance

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    Provenance, or information about the sources, derivation, custody or history of data, has been studied recently in a number of contexts, including databases, scientific workflows and the Semantic Web. Many provenance mechanisms have been developed, motivated by informal notions such as influence, dependence, explanation and causality. However, there has been little study of whether these mechanisms formally satisfy appropriate policies or even how to formalize relevant motivating concepts such as causality. We contend that mathematical models of these concepts are needed to justify and compare provenance techniques. In this paper we review a theory of causality based on structural models that has been developed in artificial intelligence, and describe work in progress on a causal semantics for provenance graphs.Comment: Workshop submissio

    Database Interferencing for Decision Support

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    The use of databases for management decision support requires flexible inferencing mechanisms. The use of logic programming for these purposes is explored. To be flexible, however, this requires the logical decomposition of the database into elementary predicates

    The Animated Database Courseware (ADbC) and the Database Design Module

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    There is a need to extend the breadth and depth of database curricula and to find ways to incorporate newer technologies. One way to address this challenge is through supplementary instructional materials. However, very few supporting materials exist that aid in the teaching of teach database concepts. This was the motivation for constructing the Animated Database Courseware (ADbC) that is funded by NSF Grant #0717707. ADbC has four main modules: database design, SQL, database transactions and database security. The software has a low learning curve. It hasbeen made freely available and is located on the Internet at http://adbc.kennesaw.edu. This demonstration focuses on the Database Design Module
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