Search results for "Abstract"

showing 10 items of 1959 documents

Mappings of finite distortion : size of the branch set

2018

Abstract We study the branch set of a mapping between subsets of ℝ n {\mathbb{R}^{n}} , i.e., the set where a given mapping is not defining a local homeomorphism. We construct several sharp examples showing that the branch set or its image can have positive measure.

Applied Mathematics010102 general mathematicsbranch setsTopology01 natural sciencesSet (abstract data type)funktioteoriamappings of finite distortionDistortion0103 physical sciences010307 mathematical physics0101 mathematicsAnalysisGeometry and topologyMathematics
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Existence of doubling measures via generalised nested cubes

2012

Working on doubling metric spaces, we construct generalised dyadic cubes adapting ultrametric structure. If the space is complete, then the existence of such cubes and the mass distribution principle lead into a simple proof for the existence of doubling measures. As an application, we show that for each $\epsilon>0$ there is a doubling measure having full measure on a set of packing dimension at most $\epsilon$.

Applied MathematicsGeneral MathematicsDyadic cubesStructure (category theory)Space (mathematics)Measure (mathematics)CombinatoricsMetric spacePacking dimension28C15 (Primary) 54E50 (Secondary)Mathematics - Classical Analysis and ODEsSimple (abstract algebra)Classical Analysis and ODEs (math.CA)FOS: MathematicsUltrametric spaceMathematicsProceedings of the American Mathematical Society
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A geometrical criterion for nonexistence of constant-sign solutions for some third-order two-point boundary value problems

2020

We give a simple geometrical criterion for the nonexistence of constant-sign solutions for a certain type of third-order two-point boundary value problem in terms of the behavior of nonlinearity in the equation. We also provide examples to illustrate the applicability of our results.

Applied MathematicsMathematical analysislcsh:QA299.6-433lcsh:AnalysisType (model theory)nonexistence of solutionsthird-order two-point boundary value problemsNonlinear systemThird orderSimple (abstract algebra)comparison methods for the first zero functionsBoundary value problemConstant (mathematics)Value (mathematics)AnalysisMathematicsSign (mathematics)Nonlinear Analysis
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Stochastic linearization of MDOF systems under parametric excitations

1992

Abstract The stochastic linearization approach is examined for non-linear systems subjected to parametric type excitations. It is shown that, for these systems too, stochastic linearization and Gaussian closure are two equivalent approaches if the former is applied to the coefficients of the Ito differential rule. A critical review of other stochastic linearization approaches is also presented and discussed by means of simple examples.

Applied MathematicsMechanical EngineeringGaussianClosure (topology)symbols.namesakeMechanics of MaterialsLinearizationSimple (abstract algebra)Control theorysymbolsApplied mathematicsRandom vibrationFeedback linearizationDifferential (mathematics)Parametric statisticsMathematics
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Branch-Price-and-Cut for the Soft-Clustered Capacitated Arc-Routing Problem

2021

The soft-clustered capacitated arc-routing problem (SoftCluCARP) is a variant of the classical capacitated arc-routing problem. The only additional constraint is that the set of required edges, that is, the streets to be serviced, is partitioned into clusters, and feasible routes must respect the soft-cluster constraint, that is, all required edges of the same cluster must be served by the same vehicle. In this article, we design an effective branch-price-and-cut algorithm for the exact solution of the SoftCluCARP. Its new components are a metaheuristic and branch-and-cut-based solvers for the solution of the column-generation subproblem, which is a profitable rural clustered postman tour …

Arc routing050210 logistics & transportationMathematical optimization021103 operations researchComputer science05 social sciencesBranch-price-and-cut0211 other engineering and technologiesTransportation02 engineering and technologyTravelling salesman problemConstraint (information theory)Set (abstract data type)Branch-and-cut0502 economics and businessRouting (electronic design automation)DistrictingBranch and cutArc routingCivil and Structural EngineeringTransportation Science
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Methyl vinyl ketone+OH and methacrolein+OH oxidation reactions: a master equation analysis of the pressure- and temperature-dependent rate constants.

2006

High-level electronic structure calculations and master equation analyses were carried out to obtain the pressure- and temperature-dependent rate constants of the methyl vinyl ketone+OH and methacrolein+OH reactions. The balance between the OH addition reactions at the high-pressure limit, the OH addition reactions in the fall-off region, and the pressure-independent hydrogen abstractions involved in these multiwell and multichannel systems, has been shown to be crucial to understand the pressure and temperature dependence of each global reaction. In particular, the fall-off region of the OH addition reactions contributes to the inverse temperature dependence of the rate constants in the Ar…

Arrhenius equationAddition reactionHydrogenChemistryOrganic Chemistrychemistry.chemical_elementMethacroleinGeneral ChemistryPhotochemistryHydrogen atom abstractionRedoxCatalysischemistry.chemical_compoundsymbols.namesakeReaction rate constantMethyl vinyl ketonesymbolsChemistry (Weinheim an der Bergstrasse, Germany)
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A Data-Based Approach for Modeling and Analysis of Vehicle Collision by LPV-ARMAX Models

2013

Published version of an article in the journal: Journal of Applied Mathematics. Also available from the publisher at: http://dx.doi.org/10.1155/2013/452391 Open Access Vehicle crash test is considered to be the most direct and common approach to assess the vehicle crashworthiness. However, it suffers from the drawbacks of high experiment cost and huge time consumption. Therefore, the establishment of a mathematical model of vehicle crash which can simplify the analysis process is significantly attractive. In this paper, we present the application of LPV-ARMAX model to simulate the car-to-pole collision with different initial impact velocities. The parameters of the LPV-ARMAX are assumed to …

Article SubjectComputer scienceApplied Mathematicslcsh:MathematicsProcess (computing)Collisionlcsh:QA1-939Set (abstract data type)Identification (information)High fidelityControl theoryCrashworthinessVDP::Matematikk og Naturvitenskap: 400::Matematikk: 410::Anvendt matematikk: 413Test dataMotor vehicle crashJournal of Applied Mathematics
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Delay-Probability-Distribution-Dependent FIR Filtering Design with Envelope Constraints

2013

Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2013/930927 Open Access This paper studies the problem of H∞ finite-impulse response (FIR) filtering design of time-delay system. The time-delay considered here is time-varying meanwhile with a certain stochastic characteristic, and the probability of delay distribution is assumed to be known. Furthermore, the requirement of pulse-shape is also considered in filter design. Employing the information about the size and probability distribution of delay, a delay-probability-distribution-dependent criterion is proposed for the filtering error syst…

Article SubjectDistribution (number theory)lcsh:MathematicsGeneral MathematicsGeneral EngineeringLinear matrixlcsh:QA1-939Set (abstract data type)Filter designlcsh:TA1-2040Control theoryProbability distributionVDP::Matematikk og Naturvitenskap: 400::Matematikk: 410::Analyse: 411lcsh:Engineering (General). Civil engineering (General)Envelope (mathematics)MathematicsMathematical Problems in Engineering
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A spiking network for body size learning inspired by the fruit fly

2013

The concept of peripersonal space is an interesting research topics for psychologists, neurobiologists and for robotic applications. A living being can learn the representation of its own body to take the correct behavioral decision when interacting with the world. To transfer these important learning mechanisms on bio-robots, simple and efficient solutions can be found in the insect world. In this paper a neural-based model for body-size learning is proposed taking into account the results obtained in experiments with fruit flies. Simulations and experimental results on a roving platform are reported and compared with the biological counterpart.

Artificial neural networkbusiness.industryComputer scienceComputational modelMobile robotBiologically inspired modelsSpace (commercial competition)Body sizeMachine learningcomputer.software_genreDrosophila melanogasterSimple (abstract algebra)Biologically inspired models; Drosophila melanogaster; Computational modelArtificial intelligenceBiomimeticsbusinessRepresentation (mathematics)computer
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Discovering representative models in large time series databases

2004

The discovery of frequently occurring patterns in a time series could be important in several application contexts. As an example, the analysis of frequent patterns in biomedical observations could allow to perform diagnosis and/or prognosis. Moreover, the efficient discovery of frequent patterns may play an important role in several data mining tasks such as association rule discovery, clustering and classification. However, in order to identify interesting repetitions, it is necessary to allow errors in the matching patterns; in this context, it is difficult to select one pattern particularly suited to represent the set of similar ones, whereas modelling this set with a single model could…

Association rule learningDiscretizationComputer scienceContext (language use)Correlation and dependencecomputer.software_genreSet (abstract data type)CardinalityKnowledge extractionMotif extraction Pattern discoveryPattern matchingData miningCluster analysisTime complexitycomputer
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