1,721,049 research outputs found
Bounded Model Property for Multi-Context Systems
No full textOur general interest is to understand the inherent complexity of contextual reasoning. In this paper we establish the bounded model property for propositional multi-context systems with finite sets of bridge rules: the number of local models needed to satisfy a set of formulas in such systems is bounded by the number of formulas in that set plus the number of bridge rules of the system. Using this result we achieve NP-completeness and a tractable encoding of contextual satisfiability into propositional satisfiability. In doing so, we pave the way for the implementation of contextual reasoners based on already existing specialized SAT solver
Complexity of Contextual Reasoning
Get PDFThe aim of this paper is to delineate the computational complexity of propositional multi-context systems. We establish NP-completeness by translating multi-context systems into bounded modal, and obtain more refined complexity results by achieving the so-called bounded model property: the number of local models needed to satisfy a set of formulas in a multi-context system is bounded by the number of formulas in that set plus the number of bridge rules of the system. Exploiting this property of multi-context systems, we are able to encode contextual satisfiability problems into propositional ones, providing for the implementation of contextual reasoners based on specialized Sat solvers. We apply our results to improve on complexity bounds for Mc-Carthy's propositional logic of context - we show that satisfiability in this framework can be settled in non-deterministic polynomial time
Satisfiability for Propositional Contexts
Get PDFWe propose a sound and complete satisfiability algorithm for propositional multi-context systems. In essence, the algorithm is a distribution policy built on top of local reasoning procedures, one for each context, which can be implemented by (a diversity of) customized state-of-the-art SAT solvers. The foremost intuition that has motivated our algorithm, and the very potential strength of contextual reasoning, is that of keeping reasoning as local as possible. In doing so, we improve on earlier established complexity results by Massacci. Moreover, our approach could be applied to enhance recent proposals by Amir and Mcilraith towards a new partition-based reasoning paradigm; particularly, our formalism allows for a more expressive description of interpartition relations, and we provide an algorithm that is explicitly designed to deal with this expressiveness
Lexical and Derivational Meaning in Vector-Based Models of Relativisation
No full textSadrzadeh et al (2013) present a compositional distributional analysis of relative clauses in English in terms of the Frobenius algebraic structure of finite dimensional vector spaces. The analysis relies on distinct type assignments and lexical recipes for subject vs object relativisation. The situation for Dutch is different: because of the verb final nature of Dutch, relative clauses are ambiguous between a subject vs object relativisation reading. Using an extended version of Lambek calculus, we present a compositional distributional framework that accounts for this derivational ambiguity, and that allows us to give a single meaning recipe for the relative pronoun reconciling the Frobenius semantics with the demands of Dutch derivational syntax
Preliminary Powerplant concepts of a DSM production support vessel
No full textMarine Technology | Marine Engineerin
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Free Variable Economy
Get PDFSeveral authors have recently argued that semantic interpretation is subject to economy constraints. In particular, Fox (1999) argued that the interpretation of pronouns is subject to BINDING ECONOMY, which favors local binding over non-local binding. The present paper points out a problem for BINDING ECONOMY. The aim, then, is to see if this problem can be resolved in a conservative way, that is, preserving the general idea that interpretation is subject to economy constraints. The suggested solution is to consider a different economy criterion. The proposed constraint, FREE VARIABLE ECONOMY, disfavors free variables rather than non-local binding. It avoids the problem that BINDING ECONOMY runs into, and preserves the general idea that semantic interpretation is subject to economy constraints. 
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