11,328 research outputs found

    A unified theory of granularity, vagueness and approximation

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    Abstract: We propose a view of vagueness as a semantic property of names and predicates. All entities are crisp, on this semantic view, but there are, for each vague name, multiple portions of reality that are equally good candidates for being its referent, and, for each vague predicate, multiple classes of objects that are equally good candidates for being its extension. We provide a new formulation of these ideas in terms of a theory of granular partitions. We show that this theory provides a general framework within which we can understand the relation between vague terms and concepts and the corresponding crisp portions of reality. We also sketch how it might be possible to formulate within this framework a theory of vagueness which dispenses with the notion of truth-value gaps and other artifacts of more familiar approaches. Central to our approach is the idea that judgments about reality involve in every case (1) a separation of reality into foreground and background of attention and (2) the feature of granularity. On this basis we attempt to show that even vague judgments made in naturally occurring contexts are not marked by truth-value indeterminacy. We distinguish, in addition to crisp granular partitions, also vague partitions, and reference partitions, and we explain the role of the latter in the context of judgments that involve vagueness. We conclude by showing how reference partitions provide an effective means by which judging subjects are able to temper the vagueness of their judgments by means of approximations

    Directly depicting granular ontologies

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    Published in extended form as "Endurants and Perdurants in Directly Depicting Ontologies", We propose an ontological theory that is powerful enough to describe both complex spatio-temporal processes and the enduring entities that participate in such processes. For this purpose we distinguish between ontologies and metaontology. Ontologies are based on very simple directly depicting languages and fall into two major categories: ontologies of type SPAN and ontologies of type SNAP. These represent two complementary perspectives on reality and result in distinct though compatible systems of categories. In a SNAP (snapshot) ontology we have the enduring entities in a given domain as they exist to be inventoried at some given moment of time. In a SPAN ontology we have perduring entities such as processes and their parts and aggregates. We argue that both kinds of ontology are required, together with the meta-ontology which joins them together. On the level of meta-ontology we are able to impose constraints on ontologies of a sort which can support efficient processing of large amounts of data

    Race as a Dimension in Children\u27s TV Advertising: The Need for More Research

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    Most of the current research in the area of television advertising to children deal entirely with white populations. This exclusion of black subjects exists in spite of an abundance of research in education, sociology and psychology which suggests differences in the socialization of black and white children. The present article reviews major studies of television and children and black versus white child development. The authors conclude with several suggestions for further research

    tmRNA - a novel high-copy-number RNA diagnostic target - its application for Staphylococcus aureus detection using real-time NASBA

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    A real-time nucleic acid sequence-based amplification assay, targeting tmRNA, was designed for the rapid identification of Staphylococcus aureus. The selectivity of the assay was confirmed against a panel of 76 Staphylococcus strains and species and 22 other bacterial species. A detection limit of 1 cell equivalent was determined for the assay. A chimeric in vitro transcribed internal amplification control was developed and included in the assay. Application of the assay in natural and artificially contaminated unpasteurized (raw) milk enabled detection of 1-10 CFUS. aureus mL(-1) in 3-4 h, without the need for culture enrichment. Staphylococcus aureus was detected in all artificially contaminated milk samples (n=20) and none of the natural milk samples (n=20). Microbiological analysis of the natural milk samples was performed in parallel according to ISO 6888-3 and confirmed the absence of S. aureus. The method developed in this study has the potential to enable the specific detection of S. aureus in raw milk in a significantly shorter time frame than current standard methods. The assay further demonstrates the usefulness of tmRNA/ssrA as a nucleic acid diagnostic target

    Quantum Corrections to the Reissner-Nordstr\"{o}m and Kerr-Newman Metrics

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    We use effective field theory techniques to examine the quantum corrections to the gravitational metrics of charged particles, with and without spin. In momentum space the masslessness of the photon implies the presence of nonanalytic pieces q2,q2logq2\sim \sqrt{-q^2},q^2\log -q^2 etc. in the form factors of the energy-momentum tensor. We show how the former reproduces the classical non-linear terms of the Reissner-Nordstr\"{o}m and Kerr-Newman metrics while the latter can be interpreted as quantum corrections to these metrics, of order Gα/mr3G\alpha\hbar/mr^3Comment: 16 page latex file with two figure
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