Search results for "QA1-939"

showing 10 items of 527 documents

Dual attachment pairs in categorically-algebraic topology

2011

[EN] The paper is a continuation of our study on developing a new approach to (lattice-valued) topological structures, which relies on category theory and universal algebra, and which is called categorically-algebraic (catalg) topology. The new framework is used to build a topological setting, based in a catalg extension of the set-theoretic membership relation "e" called dual attachment, thereby dualizing the notion of attachment introduced by the authors earlier. Following the recent interest of the fuzzy community in topological systems of S. Vickers, we clarify completely relationships between these structures and (dual) attachment, showing that unlike the former, the latter have no inh…

(pre)image operatorWeak topologyTopological algebralcsh:Mathematicslcsh:QA299.6-433Quasi-framelcsh:AnalysisTopological spacelcsh:QA1-939Topological vector spaceHomeomorphismAlgebraDual attachment pair(LM)-fuzzy topologyTrivial topologyCategory of topological spacesVarietyGeometry and TopologyGeneral topology(lattice-valued) categorically-algebraic topologyTopological systemQuasi-coincidence relationSpatialization(localic) algebraMathematics
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Voronovskaya type results and operators fixing two functions

2021

The present paper deals with positive linear operators which fix two functions. The transfer of a given sequence (Ln) of positive linear operators to a new sequence (Kn) is investigated. A general procedure to construct sequences of positive linear operators fixing two functions which form an Extended Complete Chebyshev system is described. The Voronovskaya type formula corresponding to the new sequence which is strongly influenced by the nature of the fixed functions is obtained. In the last section our results are compared with other results existing in literature.

010101 applied mathematicsextended complete Chebyshev systemModeling and Simulation010102 general mathematicsQA1-939operators fixing two functionsVoronovskaya type theorem0101 mathematics01 natural sciencesAnalysisMathematicspositive linear operatorsMathematical Modelling and Analysis
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Constant sign and nodal solutions for nonlinear robin equations with locally defined source term

2020

We consider a parametric Robin problem driven by a nonlinear, nonhomogeneous differential operator which includes as special cases the p-Laplacian and the (p,q)-Laplacian. The source term is parametric and only locally defined (that is, in a neighborhood of zero). Using suitable cut-off techniques together with variational tools and comparison principles, we show that for all big values of the parameter, the problem has at least three nontrivial smooth solutions, all with sign information (positive, negative and nodal).

010102 general mathematicsMathematical analysisMathematics::Spectral Theory01 natural sciencesLocally defined reactionTerm (time)Critical groups010101 applied mathematicsNonlinear systemConstant sign and nodal solutionsSettore MAT/05 - Analisi MatematicaModeling and SimulationQA1-9390101 mathematicsNonlinear maximum principleConstant (mathematics)NODALMathematicsAnalysisSign (mathematics)MathematicsNonlinear regularity
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THE GYROTRON STARTUP SCENARIO IN THE SINGLE MODE TIME DEPENDENT APPROACH

2019

The paper explains how to solve the Gyrotron equation system in the Single Mode Time Dependent Approach. In particular, we point out problems encountered when solving these well-known equations. The starting current estimation approach a using time model is suggested. The solution has been implemented in the Matlab code, which is attached to the article.

010302 applied physicsPhysicstime dependent approachgyrotronNuclear engineeringSingle-mode optical fiberMatlab code01 natural sciences010305 fluids & plasmaslaw.inventiondifferential equationlawModeling and SimulationGyrotron0103 physical sciencesQA1-939MathematicsAnalysisMathematical Modelling and Analysis
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Incorporating Biotic Information in Species Distribution Models: A Coregionalized Approach

2021

In this work, we discuss the use of a methodological approach for modelling spatial relationships among species by means of a Bayesian spatial coregionalized model. Inference and prediction is performed using the integrated nested Laplace approximation methodology to reduce the computational burden. We illustrate the performance of the coregionalized model in species interaction scenarios using both simulated and real data. The simulation demonstrates the better predictive performance of the coregionalized model with respect to the univariate models. The case study focus on the spatial distribution of a prey species, the European anchovy (Engraulis encrasicolus), and one of its predator spe…

0106 biological sciencesGeneral MathematicsSpecies distributionBayesian probabilityspeciescoregionalized modelsBayesian hierarchical models010603 evolutionary biology01 natural sciences010104 statistics & probabilitymodelsEngraulisHakeAnchovyStatisticsComputer Science (miscellaneous)INLAdistributionEuropean anchovyPesqueríasCentro Oceanográfico de Murcia0101 mathematicsEngineering (miscellaneous)SPDEfishspecies interactionbiologymathematicslcsh:MathematicsUnivariateMerluccius merlucciusbiology.organism_classificationlcsh:QA1-939fisheriesEnvironmental sciencepredation
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George-Veeramani Fuzzy Metrics Revised

2018

In this note, we present an alternative approach to the concept of a fuzzy metric, calling it a revised fuzzy metric. In contrast to the traditional approach to the theory of fuzzy metric spaces which is based on the use of a t-norm, we proceed from a t-conorm in the definition of a revised fuzzy metric. Here, we restrict our study to the case of fuzzy metrics as they are defined by George-Veeramani, however, similar revision can be done also for some other approaches to the concept of a fuzzy metric.

0209 industrial biotechnologyLogicComputer scienceMathematics::General Mathematicst-norm02 engineering and technologyFuzzy logic<i>t</i>-norm020901 industrial engineering & automationGEORGE (programming language)0202 electrical engineering electronic engineering information engineeringt-conormMathematical PhysicsAlgebra and Number Theorybusiness.industrylcsh:MathematicsContrast (statistics)T-normlcsh:QA1-939Fuzzy metric spaceComputingMethodologies_PATTERNRECOGNITIONrestrictMetric (mathematics)<i>t</i>-conormfuzzy metric020201 artificial intelligence & image processingGeometry and TopologyArtificial intelligenceComputingMethodologies_GENERALbusinessAnalysisAxioms
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Using Inverse Reinforcement Learning with Real Trajectories to Get More Trustworthy Pedestrian Simulations

2020

Reinforcement learning is one of the most promising machine learning techniques to get intelligent behaviors for embodied agents in simulations. The output of the classic Temporal Difference family of Reinforcement Learning algorithms adopts the form of a value function expressed as a numeric table or a function approximator. The learned behavior is then derived using a greedy policy with respect to this value function. Nevertheless, sometimes the learned policy does not meet expectations, and the task of authoring is difficult and unsafe because the modification of one value or parameter in the learned value function has unpredictable consequences in the space of the policies it represents…

0209 industrial biotechnologyreinforcement learningComputer scienceGeneral Mathematics02 engineering and technologypedestrian simulationTask (project management)learning by demonstration020901 industrial engineering & automationAprenentatgeInformàticaBellman equation0202 electrical engineering electronic engineering information engineeringComputer Science (miscellaneous)Reinforcement learningEngineering (miscellaneous)business.industrycausal entropylcsh:MathematicsProcess (computing)020206 networking & telecommunicationsFunction (mathematics)inverse reinforcement learninglcsh:QA1-939Problem domainTable (database)Artificial intelligenceTemporal difference learningbusinessoptimizationMathematics
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Grading investment diversification options in presence of non-historical financial information

2021

Modern portfolio theory deals with the problem of selecting a portfolio of financial assets such that the expected return is maximized for a given level of risk. The forecast of the expected individual assets’ returns and risk is usually based on their historical returns. In this work, we consider a situation in which the investor has non-historical additional information that is used for the forecast of the expected returns. This implies that there is no obvious statistical risk measure any more, and it poses the problem of selecting an adequate set of diversification constraints to mitigate the risk of the selected portfolio without losing the value of the non-statistical information owne…

021103 operations researchIndex (economics)diversificationGeneral MathematicsRisk measurelcsh:Mathematics0211 other engineering and technologiesDiversification (finance)UNESCO::CIENCIAS ECONÓMICAS02 engineering and technologyInvestment (macroeconomics)lcsh:QA1-939:CIENCIAS ECONÓMICAS [UNESCO]value of informationValue of information0202 electrical engineering electronic engineering information engineeringComputer Science (miscellaneous)EconomicsEconometricsPortfolioExpected returnportfolio selection020201 artificial intelligence & image processingEngineering (miscellaneous)Modern portfolio theory
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On a Planar Dynamical System Arising in the Network Control Theory

2016

We study the structure of attractors in the two-dimensional dynamical system that appears in the network control theory. We provide description of the attracting set and follow changes this set suffers under the changes of positive parameters µ and Θ.

0301 basic medicineDynamical systems theoryPhase portraitattractor selection020206 networking & telecommunicationsphase portraits02 engineering and technologyDynamical systemnetworks controldynamical systemLinear dynamical system03 medical and health sciences030104 developmental biologyProjected dynamical systemControl theoryModeling and SimulationAttractor0202 electrical engineering electronic engineering information engineeringQA1-939Statistical physicsLimit setRandom dynamical systemAnalysisMathematicsMathematicsMathematical Modelling and Analysis
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Miscellaneous Graph Preliminaries

2020

Summary This article contains many auxiliary theorems which were missing in the Mizar Mathematical Library [2] to the best of the author’s knowledge. Most of them regard graph theory as formalized in the GLIB series (cf. [8]) and most of them are preliminaries needed in [7] or other forthcoming articles.

05c07Discrete mathematicsComputational Mathematicsvertex degreesgraph theoryApplied MathematicsQA1-939Graph (abstract data type)Graph theory68v20MathematicsMathematicsFormalized Mathematics
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