27,754 research outputs found

    A Case against Representationalism

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    The case of blurry vision has been cited by many as a counterexample to representationalism in the theory of perception. Specifically, it is claimed that the phenomenon of blurry vision is incompatible with the supervenience thesis which is at the root of representationalism. Michael Tye, a leading representationalist, has responded to such objections by giving an account of blurry vision in a way that, allegedly, renders it compatible with representationalism. In this paper I argue that Tye’s account of blurry vision, though blocking one line of objection, cannot save representationalism. I then assimilate cases of blurry vision as well as similar cases to the more general category of indeterminate experiences

    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

    Linking individual behaviour to community scale patterns in fungi

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    The fungi comprise a separate kingdom of life and epitomise the indeterminate growth form. Very little is known about the factors that influence the nature of fungal diversity and the link between individual behaviour and the structure and function of fungal communities is particularly poorly understood. Here, we present a theoretical framework that is capable of elucidating this link. An individual-based model for fungal community dynamics is introduced that has been developed from a physiologically based model for the fungal phenotype. The model is used to explore the role of individual interactions, the production of an external inhibitor field and the quality of the external environment on the structure and diversity of the resulting community. We show that traits relating to growth rate, autophagic behaviour and the production of inhibitors are key in influencing the success of a particular genotype in a community. The species richness increases with the amount of available resource. This is the first model of fungal community dynamics that introduces the concept of a biomass-based abundance distribution function that can be described by the log-normal form which typically corresponds to communities in equilibrium. The species abundance curve was stable to changes in the relative location of inocula, although the ranked abundance of the individuals was not. We present the first attempt to identify the traits that affect the form of that curve. Future studies should examine the role of environmental heterogeneity and spore dispersal

    Clinical guidelines as plans: An ontological theory

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    Clinical guidelines are special types of plans realized by collective agents. We provide an ontological theory of such plans that is designed to support the construction of a framework in which guideline-based information systems can be employed in the management of workflow in health care organizations. The framework we propose allows us to represent in formal terms how clinical guidelines are realized through the actions of are realized through the actions of individuals organized into teams. We provide various levels of implementation representing different levels of conformity on the part of health care organizations. Implementations built in conformity with our framework are marked by two dimensions of flexibility that are designed to make them more likely to be accepted by health care professionals than standard guideline-based management systems. They do justice to the fact 1) that responsibilities within a health care organization are widely shared, and 2) that health care professionals may on different occasions be non-compliant with guidelines for a variety of well justified reasons. The advantage of the framework lies in its built-in flexibility, its sensitivity to clinical context, and its ability to use inference tools based on a robust ontology. One disadvantage lies in its complicated implementation

    Charter School Funding: Inequity in the City

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    Public charter schools are a growing part of K-12 education. Charter schools are public schools that are granted operational autonomy by their authorizing agency in return for a commitment to achieve specific performance goals. Like traditional public schools, charter schools are free to students and overseen by the state. Unlike traditional public schools, however, most charters are open to all students who wish to apply, regardless of where they live. If a charter school is over-subscribed, usually random lotteries determine which students will be admitted. Most charter schools are independent of the traditional public school district in which they operate

    The evolution of Local Labour Market Areas in contrasting region

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    In many European local labour markets, a growing minority of workers are making longer commuting trips. One consequence for research into journey-to-work flows, which usually seeks to identify the boundaries of local labour market areas (LLMAs), is that these boundaries represent a ¡¥snap shot¡¦ of an increasingly volatile pattern. The challenge for regional science is how best to represent the way LLMAs evolve. «Is it sufficient to simply update maps, using a consistent method which is applied to successive ¡¥snap-shot¡¦ datasets? This approach will be illustrated in contrasting regions. «Is it possible to produce new approaches to analysis which can better draw attention to those areas where change has been rather more, or less, strong? The paper will end with some explorations in pursuit of this aim.

    Computing HF^ by factoring mapping classes

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    Bordered Heegaard Floer homology is an invariant for three-manifolds with boundary. In particular, this invariant associates to a handle decomposition of a surface F a differential graded algebra, and to an arc slide between two handle decompositions, a bimodule over the two algebras. In this paper, we describe these bimodules for arc slides explicitly, and then use them to give a combinatorial description of HF^ of a closed three-manifold, as well as the bordered Floer homology of any 3-manifold with boundary.Comment: 106 pages, 46 figure

    Reactant Jetting in Unstable Detonation

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    We note the common existence of a supersonic jet structure locally embedded within a surrounding transonic flow field in the hitherto unrelated phenomena of unstable gaseous detonation and hypervelocity blunt body shock wave interaction. Extending prior results that demonstrate the consequences of reduced endothermic reaction rate for the supersonic jet fluid in the blunt body case, we provide an explanation for observations of locally reduced OH PLIF signal in images of the keystone reaction zone structure of weakly unstable detonations. Modeling these flow features as exothermically reacting jets with similarly reduced reaction rates, we demonstrate a mechanism for jetting of bulk pockets of unreacted fluid with potentially differing kinetic pathways into the region behind the primary detonation front of strongly unstable mixtures. We examine the impact of mono-atomic and diatomic diluents on transverse structure. The results yield insight into the mechanisms of transition and characteristic features of both weakly and strongly unstable mixtures
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