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AE Institutional Approach and Enterprise Creation: Support Systems in the Case of Small City in Rural and Peripheral Areas of Portugal Amfiteatru Economic 258 INSTITUTIONAL APPROACH AND ENTERPRISE CREATION: SUPPORT SYSTEMS IN THE CASE OF SMALL CITY IN RUR
"... The research aims to identify and analyse the formal institutional factors in the environment that constrain the creation of industrial enterprises in small city in rural and peripheral areas of Portugal, namely Covilhã County. It has as reference sources several approaches about enterprise creation ..."
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institutional programs/services. Investigation hypotheses are formulated and subject them to empiric tests. The results, from the offer point of view of the services/programs, show that, duplication of resources and efforts on the part of institutions in the region often occurs making coordination more
Matrix Model as a Mirror of ChernSimons Theory
, 2002
"... Using mirror symmetry, we show that ChernSimons theory on certain manifolds such as lens spaces reduces to a novel class of Hermitian matrix models, where the measure is that of unitary matrix models. We show that this agrees with the more conventional canonical quantization of ChernSimons theory. ..."
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Cited by 134 (17 self)
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Using mirror symmetry, we show that ChernSimons theory on certain manifolds such as lens spaces reduces to a novel class of Hermitian matrix models, where the measure is that of unitary matrix models. We show that this agrees with the more conventional canonical quantization of ChernSimons theory. Moreover, large N dualities in this context lead to computation of all genus Amodel topological amplitudes on toric CalabiYau manifolds in terms of matrix integrals. In the context of type IIA superstring compactifications on these CalabiYau manifolds with wrapped D6 branes (which are dual to Mtheory on G2 manifolds) this leads to engineering and solving Fterms for N = 1 supersymmetric gauge theories with superpotentials involving certain multitrace operators
Ontological Semantics
, 2004
"... This book introduces ontological semantics, a comprehensive approach to the treatment of text meaning by computer. Ontological semantics is an integrated complex of theories, methodologies, descriptions and implementations. In ontological semantics, a theory is viewed as a set of statements determin ..."
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Cited by 126 (37 self)
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This book introduces ontological semantics, a comprehensive approach to the treatment of text meaning by computer. Ontological semantics is an integrated complex of theories, methodologies, descriptions and implementations. In ontological semantics, a theory is viewed as a set of statements determining the format of descriptions of the phenomena with which the theory deals. A theory is associated with a methodology used to obtain the descriptions. Implementations are computer systems that use the descriptions to solve specific problems in text processing. Implementations of ontological semantics are combined with other processing systems to produce applications, such as information extraction or machine translation. The theory of ontological semantics is built as a society of microtheories covering such diverse ground as specific language phenomena, world knowledge organization, processing heuristics and issues relating to knowledge representation and implementation system architecture. The theory briefly sketched above is a toplevel microtheory, the ontological semantics theory per se. Descriptions in ontological semantics include text meaning representations, lexical entries, ontological concepts and instances as well as procedures for manipulating texts and their meanings. Methodologies in ontological semantics are sets of techniques and instructions for acquiring and
Differentially Private Recommender Systems: Building Privacy into the Netflix Prize Contenders
"... We consider the problem of producing recommendations from collective user behavior while simultaneously providing guarantees of privacy for these users. Specifically, we consider the Netflix Prize data set, and its leading algorithms, adapted to the framework of differential privacy. Unlike prior pr ..."
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Cited by 123 (3 self)
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We consider the problem of producing recommendations from collective user behavior while simultaneously providing guarantees of privacy for these users. Specifically, we consider the Netflix Prize data set, and its leading algorithms, adapted to the framework of differential privacy. Unlike prior privacy work concerned with cryptographically securing the computation of recommendations, differential privacy constrains a computation in a way that precludes any inference about the underlying records from its output. Such algorithms necessarily introduce uncertainty— i.e., noise—to computations, trading accuracy for privacy. We find that several of the leading approaches in the Netflix Prize competition can be adapted to provide differential privacy, without significantly degrading their accuracy. To adapt these algorithms, we explicitly factor them into two parts, an aggregation/learning phase that can be performed with differential privacy guarantees, and an individual recommendation phase that uses the learned correlations and an individual’s data to provide personalized recommendations. The adaptations are nontrivial, and involve both careful analysis of the perrecord sensitivity of the algorithms to calibrate noise, as well as new postprocessing steps to mitigate the impact of this noise. We measure the empirical tradeoff between accuracy and privacy in these adaptations, and find that we can provide nontrivial formal privacy guarantees while still outperforming the Cinematch baseline Netflix provides.
The MMachine Multicomputer
, 1995
"... The MMachine is an experimental multicomputer being developed to test architectural concepts motivated by the constraints of modern semiconductor technology and the demands of programming systems. The MMachine computing nodes are con nected with a 3D mesh network; each node is a multithreaded pr ..."
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Cited by 114 (13 self)
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The MMachine is an experimental multicomputer being developed to test architectural concepts motivated by the constraints of modern semiconductor technology and the demands of programming systems. The MMachine computing nodes are con nected with a 3D mesh network; each node is a multithreaded
MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF STA NUARDS 963 S
"... UNC~SSIHEO _ i rur iS L t i j i~ITY C ~ AS~. I I ICAI IOp4 or I.IIS ~‘ * ‘.f IIP~.n I).,. I... ~ — , V V ..."
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UNC~SSIHEO _ i rur iS L t i j i~ITY C ~ AS~. I I ICAI IOp4 or I.IIS ~‘ * ‘.f IIP~.n I).,. I... ~ — , V V
Robust Solutions To Uncertain Semidefinite Programs
 SIAM J. OPTIMIZATION
, 1998
"... In this paper we consider semidefinite programs (SDPs) whose data depend on some unknown but bounded perturbation parameters. We seek "robust" solutions to such programs, that is, solutions which minimize the (worstcase) objective while satisfying the constraints for every possible value ..."
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Cited by 109 (8 self)
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In this paper we consider semidefinite programs (SDPs) whose data depend on some unknown but bounded perturbation parameters. We seek "robust" solutions to such programs, that is, solutions which minimize the (worstcase) objective while satisfying the constraints for every possible value of parameters within the given bounds. Assuming the data matrices are rational functions of the perturbation parameters, we show how to formulate sufficient conditions for a robust solution to exist as SDPs. When the perturbation is "full," our conditions are necessary and sufficient. In this case, we provide sufficient conditions which guarantee that the robust solution is unique and continuous (Hölderstable) with respect to the unperturbed problem's data. The approach can thus be used to regularize illconditioned SDPs. We illustrate our results with examples taken from linear programming, maximum norm minimization, polynomial interpolation, and integer programming.
A Gröbner free alternative for polynomial system solving
 Journal of Complexity
, 2001
"... Given a system of polynomial equations and inequations with coefficients in the field of rational numbers, we show how to compute a geometric resolution of the set of common roots of the system over the field of complex numbers. A geometric resolution consists of a primitive element of the algebraic ..."
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Cited by 107 (19 self)
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Given a system of polynomial equations and inequations with coefficients in the field of rational numbers, we show how to compute a geometric resolution of the set of common roots of the system over the field of complex numbers. A geometric resolution consists of a primitive element of the algebraic extension defined by the set of roots, its minimal polynomial and the parametrizations of the coordinates. Such a representation of the solutions has a long history which goes back to Leopold Kronecker and has been revisited many times in computer algebra. We introduce a new generation of probabilistic algorithms where all the computations use only univariate or bivariate polynomials. We give a new codification of the set of solutions of a positive dimensional algebraic variety relying on a new global version of Newton’s iterator. Roughly speaking the complexity of our algorithm is polynomial in some kind of degree of the system, in its height, and linear in the complexity of evaluation
Artificial Boundaries and Flux and Pressure Conditions for the Incompressible NavierStokes Equations
, 1992
"... Fluid dynamical problems are often conceptualized in unbounded domains. But most methods of numerical simulation then require a truncation of the conceptual domain to a bounded one, thereby introducing artificial boundaries. Here, we analyze our experience in choosing artificial boundary conditions ..."
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Cited by 93 (8 self)
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Fluid dynamical problems are often conceptualized in unbounded domains. But most methods of numerical simulation then require a truncation of the conceptual domain to a bounded one, thereby introducing artificial boundaries. Here, we analyze our experience in choosing artificial boundary conditions implicitly, through the choice of variational formulations. We deal particularly with a class of problems that involve the prescription of pressure drops and/or net flux conditions. 1 Introduction Most flow problems of scientific or engineering interest, such as flows past obstacles, around corners, or through pipes or apertures, are first conceptualized in unbounded domains. This is an idealization intended to focus on a phenomenon of interest, free of the effects of distant boundaries. We begin this paper by reviewing the mathematical formulations for unbounded domains, of a class of problems that involve the prescription of pressure drops and/or net flux conditions. These formulations ar...
Funding criteria for research, development, and exploration projects, Econometrica 49
, 1981
"... Work reported in this document was sponsored by the Department ..."
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Cited by 95 (0 self)
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Work reported in this document was sponsored by the Department
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