Search results for "Diffusion modeling"

showing 6 items of 6 documents

The role of melt-fracture degassing in defusing explosive rhyolite eruptions at volcán Chaitén

2012

Explosive volcanic eruptions of silicic magma often evolve towards non-explosive emissions of lava. The mechanisms underlying this transition remain unclear, however, a widely cited idea holds that shear-induced magma fragmentation plays a critical role by fostering volatile loss from fragmentary magma and through ash-filled cracks termed tuffisite. We test this hypothesis by measuring H2O concentrations within glassy tuffisite from the 2008–2011 rhyolitic eruption at volcan Chaiten, Chile. We show that while H2O concentrations decrease next to tuffisite veins and at the margins of obsidian fragments, the depletions cannot account for the disparity in H2O between explosively and effusively …

Diffusion modelinggeographygeography.geographical_feature_categoryExplosive materialLavaGeochemistrySilicicVolcanologyGeophysicsVolcanoSpace and Planetary ScienceGeochemistry and PetrologyRhyoliteEarth and Planetary Sciences (miscellaneous)GeologyEarth and Planetary Science Letters
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On a Retarded Nonlocal Ordinary Differential System with Discrete Diffusion Modeling Life Tables

2021

In this paper, we consider a system of ordinary differential equations with non-local discrete diffusion and finite delay and with either a finite or an infinite number of equations. We prove several properties of solutions such as comparison, stability and symmetry. We create a numerical simulation showing that this model can be appropriate to model dynamical life tables in actuarial or demographic sciences. In this way, some indicators of goodness and smoothness are improved when comparing with classical techniques.

General Mathematicslattice dynamical systemslife tables010103 numerical & computational mathematics:CIENCIAS ECONÓMICAS [UNESCO]01 natural sciencesStability (probability)010104 statistics & probabilitydiscrete nonlocal diffusion problemsComputer Science (miscellaneous)Applied mathematics0101 mathematicsDiffusion (business)Engineering (miscellaneous)MathematicsDiffusion modelingSmoothness (probability theory)Computer simulationlcsh:MathematicsUNESCO::CIENCIAS ECONÓMICASlcsh:QA1-939Symmetry (physics)Ordinary differential systemordinary differential equationsOrdinary differential equationretarded equationsMathematics
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Diffusion modeling of COVID-19 under lockdown

2021

Viral immune evasion by sequence variation is a significant barrier to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine design and coronavirus disease-2019 diffusion under lockdown are unpredictable with subsequent waves. Our group has developed a computational model rooted in physics to address this challenge, aiming to predict the fitness landscape of SARS-CoV-2 diffusion using a variant of the bidimensional Ising model (2DIMV) connected seasonally. The 2DIMV works in a closed system composed of limited interaction subjects and conditioned by only temperature changes. Markov chain Monte Carlo method shows that an increase in temperature implicates reduced virus diffusi…

Settore MED/17 - Malattie InfettiveCoronavirus disease 2019 (COVID-19)Fitness landscapeSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)virusesComputational Mechanicsmedicine.disease_cause01 natural sciencesSettore MED/01 - Statistica Medica010305 fluids & plasmassymbols.namesakeARTICLES0103 physical sciencesmedicineStatistical physicsDiffusion (business)010306 general physicsCoronavirusFluid Flow and Transfer ProcessesPhysicsDiffusion modelingBiofluid MechanicsMechanical EngineeringMarkov chain Monte CarloCondensed Matter PhysicsDiffusion modeling COVI 19Mechanics of MaterialssymbolsIsing modelPhysics of Fluids
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Consistent device simulation model describing perovskite solar cells in steady-state, transient, and frequency domain

2019

​This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Materials & Interfaces, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsami.9b04991

Steady state (electronics)Materials scienceIMPSImpedance spectroscopy610 Medicine & health02 engineering and technology010402 general chemistrycomputer.software_genre01 natural sciencesChemical societyGeneral Materials ScienceTransient (computer programming)Device simulation10266 Clinic for Reconstructive SurgeryMaterials621.3: Elektrotechnik und ElektronikCèl·lules fotoelèctriquesTrapsPerovskite (structure)Drift-diffusion modelingProgramming languagePerovskite solar cellsHysteresis021001 nanoscience & nanotechnology2500 General Materials Science0104 chemical sciencesMobile ionsFrequency domainTransient photo-current0210 nano-technologycomputer
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Test-Taking Motivation in Education Students: Task Battery Order Affected Within-Test-Taker Effort and Importance

2020

Different types of tasks exist, including tasks for research purposes or exams assessing knowledge. According to expectation-value theory, tests are related to different levels of effort and importance within a test taker. Test-taking effort and importance in students decreased over the course of high-stakes tests or low-stakes-tests in research on test-taking motivation. However, whether test-order changes affect effort, importance, and response processes of education students have seldomly been experimentally examined. We aimed to examine changes in effort and importance resulting from variations in test battery order and their relations to response processes. We employed an experimental …

latent growth curve modelinglcsh:BF1-990educationContext (language use)Affect (psychology)050105 experimental psychologyTask (project management)exam test-taking motivationmedicinePsychology0501 psychology and cognitive sciencesGeneral PsychologyOriginal ResearchTest anxietyperspective-takingLatent growth modeling05 social sciences050301 educationCognitionmedicine.diseaseTest (assessment)lcsh:PsychologyPerspective-takingexpectation-value theorydiffusion modelingPsychology0503 educationCognitive psychologyFrontiers in Psychology
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Drifting through Basic Subprocesses of Reading: A Hierarchical Diffusion Model Analysis of Age Effects on Visual Word Recognition

2016

International audience; Reading is one of the most popular leisure activities and it is routinely performed by most individuals even in old age. Successful reading enables older people to master and actively participate in everyday life and maintain functional independence. Yet, reading comprises a multitude of subprocesses and it is undoubtedly one of the most complex accomplishments of the human brain. Not surprisingly, findings of age-related effects on word recognition and reading have been partly contradictory and are often confined to only one of four central reading subprocesses, i.e., sublexical, orthographic, phonological and lexico-semantic processing. The aim of the present study…

media_common.quotation_subjectlcsh:BF1-990letter identification150semantic decisioncomputer.software_genre050105 experimental psychology03 medical and health sciences0302 clinical medicinereadingReading (process)Lexical decision taskPsychology0501 psychology and cognitive sciencesEveryday lifeGeneral PsychologyOriginal Researchmedia_commonhierarchical diffusion modelingVisual word recognitionlexical decisionComputational modelbusiness.industry[SCCO.NEUR]Cognitive science/Neuroscience05 social sciencesagingphonological decision16. Peace & justiceCorrect responsevisual word recognitionlcsh:PsychologyWord recognition[SCCO.PSYC]Cognitive science/PsychologyArtificial intelligenceDecision thresholdPsychologybusinesscomputer030217 neurology & neurosurgeryNatural language processing
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