Search results for "STATISTICS"

showing 10 items of 7671 documents

Local regularity for quasi-linear parabolic equations in non-divergence form

2018

Abstract We consider viscosity solutions to non-homogeneous degenerate and singular parabolic equations of the p -Laplacian type and in non-divergence form. We provide local Holder and Lipschitz estimates for the solutions. In the degenerate case, we prove the Holder regularity of the gradient. Our study is based on a combination of the method of alternatives and the improvement of flatness estimates.

Applied Mathematics010102 general mathematicsMathematical analysisDegenerate energy levelsMathematics::Analysis of PDEsType (model theory)Lipschitz continuity01 natural sciencesParabolic partial differential equation010101 applied mathematicsViscosityMathematics - Analysis of PDEs35B65 35K65 35D40 35K92 35K6FOS: Mathematics0101 mathematicsDivergence (statistics)Laplace operatorAnalysisAnalysis of PDEs (math.AP)Flatness (mathematics)MathematicsNonlinear 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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Non-linear oscillators under parametric and external poisson pulses

1994

The extended Ito calculus for non-normal excitations is applied in order to study the response behaviour of some non-linear oscillators subjected to Poisson pulses. The results obtained show that the non-normality of the input can strongly affect the response, so that, in general, it can not be neglected.

Applied MathematicsMechanical EngineeringMathematical analysisAerospace EngineeringOcean EngineeringPoisson distributionItō calculusNonlinear systemsymbols.namesakeControl and Systems EngineeringControl theorysymbolsElectrical and Electronic EngineeringComputer Science::DatabasesParametric statisticsMathematicsNonlinear Dynamics
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Internal fe approximation of spaces of divergence-free functions in three-dimensional domains

1986

SUMMARY The space of divergence-free vector functions with vanishing normal flux on the boundary is approximated by subspaces of finite elements having the same property. An easy way of generating basis functions in these subspaces is shown.

Applied MathematicsMechanical EngineeringMathematical analysisComputational MechanicsFluxBoundary (topology)Basis functionSpace (mathematics)Linear subspaceFinite element methodComputer Science ApplicationsMechanics of MaterialsDivergence (statistics)Vector-valued functionMathematicsInternational Journal for Numerical Methods in Fluids
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Contrasting probabilistic and anti-optimization approaches in an applied mechanics problem

2003

Probabilistic and non-probabilistic, anti-optimization analyses of uncertainty are contrasted in this study. Specifically, the comparison of these two competing approaches is conducted for an uniform column, with initial geometric imperfection, subjected to an impact axial load. The reliability of the column is derived for the cases when the initial imperfections posses either (a) uniform probability density, (b) truncated exponential density or (c) generic truncated probability density. The problem is also analyzed in the context of an interval analysis. It is shown that in, the most important near-unity reliability range these two approaches tend to each other. Since the interval analysis…

Applied MathematicsMechanical EngineeringProbabilistic logicProbability density functionContext (language use)Condensed Matter PhysicsColumn (database)Interval arithmeticMechanics of MaterialsModeling and SimulationStatisticsRange (statistics)Axial loadApplied mathematicsGeneral Materials ScienceReliability (statistics)MathematicsInternational Journal of Solids and Structures
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Perceived benefits and constraints in vehicle automation: Data to assess the relationship between driver's features and their attitudes towards auton…

2019

This data article examines the association driver's features, perceptions and attitudes towards autonomous vehicles (AVs). The data was collected using a structured self-administrable and online-based questionnaire, applied to a full sample of 1205 Spanish drivers. The data contains 4 parts: the full set of bivariate correlations between study variables; descriptive statistics and graphical trends for each main study variable according to gender, age group and city/town size; and, finally, the dataset for further explorations in this regard. For more information, it is convenient to read the full article entitled “Perceived safety and attributed value as predictors of the intention to use a…

Applied psychologyAutonomous vehiclesPoison controlIntentionRoad SafetyBivariate analysislcsh:Computer applications to medicine. Medical informaticsOccupational safety and health03 medical and health sciences0302 clinical medicineInjury preventionPsychologySpanish driverslcsh:Science (General)Set (psychology)030304 developmental biology0303 health sciencesMultidisciplinaryDescriptive statisticsSeguretat viàriaHuman factors and ergonomicsVariable (computer science)PsicologiaAttitudeslcsh:R858-859.7PerceptionPsychology030217 neurology & neurosurgerylcsh:Q1-390Data in Brief
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Work stress, fatigue and risk behaviors at the wheel: Data to assess the association between psychosocial work factors and risky driving on Bus Rapid…

2017

This Data in Brief (DiB) article presents a hierarchical multiple linear regression model that examine the associations between psychosocial work factors and risk behaviors at the wheel in Bus Rapid Transit (BRT) drivers (n=524). The data were collected using a structured self-administrable questionnaire made of measurements of wok stress (job strain and effort- reward imbalance), fatigue (need for recovery and chronic fatigue), psychological distress and demographics (professional driving experience, hours driven per day and days working per week). The data contains 4 parts: descriptive statistics, bivariate correlations between the study variables and a regression model predicting risk be…

Applied psychologyPoison controlPsychological distresslcsh:Computer applications to medicine. Medical informaticsRisk behaviorsTransportes0502 economics and businessPsychology0501 psychology and cognitive scienceslcsh:Science (General)Fatigue050107 human factorsSimulationBus rapid transitWork stress050210 logistics & transportationBus Rapid TransportMultidisciplinaryJob strainDescriptive statisticsFatiga05 social sciencesHuman factors and ergonomicsRegression analysisChronic fatigueProfessional driverslcsh:R858-859.7PsychologyEstrés laboralPsychosocialhuman activitiesBRTlcsh:Q1-390Data in Brief
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A matter of style? testing the moderating effect of driving styles on the relationship between job strain and work-related crashes of professional dr…

2020

Abstract Different empirical studies suggest that both job strain and driving styles are significant contributors to the work-related traffic crashes suffered by professional drivers. Nevertheless, the current evidence falls considerably short when explaining why driving styles may modify (or not) the relationship between occupational stressors and professional drivers’ safety outcomes. The aim of this study was to examine whether driving styles moderate the effect of job strain on professional drivers’ Work Traffic Crashes (WTCs). This research was performed using the data collected from a sample of 753 professional drivers, responding to a self-report questionnaire on job strain (work str…

Applied psychologyPsychological interventionVulnerabilityTransportationSample (statistics)Work relatedEmpirical researchJob strain0502 economics and business0501 psychology and cognitive sciences050107 human factorsApplied PsychologyCivil and Structural Engineering050210 logistics & transportationJob strainSeguretat viària05 social sciencesStressorSalud laboralConducción de automóvilJCQModerationProfessional driversAccidentes de tránsitoAutomotive EngineeringPsychologyhuman activities
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Langage et Apprentissage en Interaction pour des Assistants Numériques Autonomes - Une Approche Développementale

2021

The rapid development of digital assistants (DA) opens the way to new modes of interaction. Some DA allows users to personalise the way they respond to queries, in particular by teaching them new procedures. This work proposes to use machine learning methods to enrich the linguistic and procedural generalisation capabilities of these systems. The challenge is to reconcile rapid learning skills, necessary for a smooth user experience, with a sufficiently large generalisation capacity. Though this is a natural human ability, it remains out-of-reach for artificial systems and this leads us to approach these issues from the perspective of developmental Artificial Intelligence. This work is thus…

Apprentissage en interaction[INFO.INFO-AI] Computer Science [cs]/Artificial Intelligence [cs.AI]Langage naturelApprentissage automatique Machine Learning[SCCO.COMP]Cognitive science/Computer science[INFO.INFO-LG] Computer Science [cs]/Machine Learning [cs.LG][SCCO.LING]Cognitive science/Linguistics[STAT.ML] Statistics [stat]/Machine Learning [stat.ML][INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI]Digital assistantsCognition[STAT.ML]Statistics [stat]/Machine Learning [stat.ML][INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG]Natural languageInteractive learning[SCCO.COMP] Cognitive science/Computer scienceMachine learning[INFO.INFO-HC]Computer Science [cs]/Human-Computer Interaction [cs.HC]Intelligence artificielle développementale[SCCO.LING] Cognitive science/Linguistics[INFO.INFO-HC] Computer Science [cs]/Human-Computer Interaction [cs.HC]developmental artificial intelligenceAssistant Numérique
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Influence of Teacher and Family Support on University Student Motivation and Engagement

2021

Although many studies endorse the notion that the way students perceive support influences their engagement, very few have explored the possible mediator role of intention to learn between these variables. The present work provides new evidence to the existing literature because it analyses the work of intention to learn (measured with expectancy–value beliefs and achievement goals) as a mediating motivational variable in the relation between university students’ external support (teacher and family) and their engagement. The Educational Situation Quality Model (MOCSE, its acronym in Spanish) has employed as a theoretical framework to perform this analysis. A sample of 267 Spanish universit…

Aprenentatge Aptitud per a l'UniversitiesProcess (engineering)Health Toxicology and MutagenesisFamily supportmedia_common.quotation_subjectlcsh:Medicine050109 social psychologySample (statistics)Student engagementStructural equation modelingArticleexpectancy beliefsMathematics educationachievement goalsHumans0501 psychology and cognitive sciencesQuality (business)teaching supportAcronymStudentsvalue beliefsmedia_commonMotivationPoint (typography)05 social scienceslcsh:RPublic Health Environmental and Occupational HealthEducació en valors050301 educationAchievementfamily supportstudent engagementEducational PersonnelFamíliaPsychology0503 educationInternational Journal of Environmental Research and Public Health
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