Search results for "Principle"

showing 10 items of 1023 documents

Ab initio simulation of (Ba,Sr)TiO3 and (Ba,Ca)TiO3 perovskite solid solutions

2019

This research was supported by the ERA-NET HarvEnPiez project. Many thanks to R. Dovesi, M.M. Kržmanc and D. Gryaznov for fruitful discussions.

First-principles computationAb initio:NATURAL SCIENCES:Physics [Research Subject Categories]Density functional theory (DFT)Perovskite solid solutionLead-free piezoelectric
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A Feature Rich Distance-Based Many-Objective Visualisable Test Problem Generator

2019

In optimiser analysis and design it is informative to visualise how a search point/population moves through the design space over time. Visualisable distance-based many-objective optimisation problems have been developed whose design space is in two-dimensions with arbitrarily many objective dimensions. Previous work has shown how disconnected Pareto sets may be formed, how problems can be projected to and from arbitrarily many design dimensions, and how dominance resistant regions of design space may be defined. Most recently, a test suite has been proposed using distances to lines rather than points. However, active use of visualisable problems has been limited. This may be because the ty…

Flexibility (engineering)Mathematical optimizationeducation.field_of_studyComputer sciencevisualisointiMulti-objective test problemsPopulationPareto principleevoluutiolaskenta0102 computer and information sciences02 engineering and technology01 natural sciencesmonitavoiteoptimointiSet (abstract data type)test suiteRange (mathematics)010201 computation theory & mathematicsevolutionary optimisation0202 electrical engineering electronic engineering information engineeringTest suite020201 artificial intelligence & image processingPoint (geometry)benchmarkingeducationGenerator (mathematics)
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Phonon Driven Floquet Matter.

2018

The effect of electron–phonon coupling in materials can be interpreted as a dressing of the electronic structure by the lattice vibration, leading to vibrational replicas and hybridization of electronic states. In solids, a resonantly excited coherent phonon leads to a periodic oscillation of the atomic lattice in a crystal structure bringing the material into a nonequilibrium electronic configuration. Periodically oscillating quantum systems can be understood in terms of Floquet theory, which has a long tradition in the study of semiclassical light-matter interaction. Here, we show that the concepts of Floquet analysis can be applied to coherent lattice vibrations. This coupling leads to p…

Floquet theoryFloquet theoryPhononphotoelectron spectroscopynonequilibrium bandstructureFOS: Physical sciencesSemiclassical physicsBioengineeringAngle-resolved photoemission spectroscopy02 engineering and technologyElectronic structureelectron?phonon coupling01 natural sciencesSettore FIS/03 - Fisica Della MateriaFirst-principles calculations0103 physical sciencesGeneral Materials Science010306 general physicsElectronic band structurePhysicsCondensed Matter - Materials Sciencepumpprobe spectroscopyCondensed matter physicsMechanical EngineeringMaterials Science (cond-mat.mtrl-sci)General Chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsExcited stateElectron configuration0210 nano-technologyNano letters
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Monitoring Electron-Photon Dressing in WSe 2

2016

Optical pumping of solids creates a non-equilibrium electronic structure where electrons and photons combine to form quasiparticles of dressed electronic states. The resulting shift of electronic levels is known as the optical Stark effect, visible as a red shift in the optical spectrum. Here we show that in a pump-probe setup we can uniquely define a non-equilibrium quasiparticle bandstructure that can be directly measurable with photoelectron spectroscopy. The dynamical photon-dressing (and undressing) of the many-body electronic states can be monitored by pump-probe time and angular resolved photoelectron spectroscopy (tr-ARPES) as the photon-dressed bandstructure evolves in time dependi…

Floquet theoryFloquet theoryPhotonphotoelectron spectroscopynonequilibrium bandstructurePhysics::OpticsBioengineering02 engineering and technologyElectronElectronic structure01 natural sciencesSettore FIS/03 - Fisica Della MateriaOptical pumpingsymbols.namesakeFirst-principles calculations0103 physical sciencesGeneral Materials Science010306 general physicsChemistryMechanical Engineeringpump-probe spectroscopyGeneral Chemistry021001 nanoscience & nanotechnologyCondensed Matter PhysicsStark effectQuasiparticlesymbolsCondensed Matter::Strongly Correlated ElectronsAtomic physics0210 nano-technologyVisible spectrumNano Letters
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Heat and mass flows coupled with stress in a continuous medium

1996

Abstract The present paper is concerned with the formulation of the generalization of theories describing heat and mass flows in a continuous medium. The considerations are based on the non-equilibrium thermodynamics. As a result the fundamental equations for the mass and heat fluxes and for the thermodynamic and mechanical fields, are obtained and the corresponding set of differential equations is formulated. Certain differences are pointed out between the general theories presented here and the thermodiffusion theory and the theory of mixtures. A thermodynamic variational principle is constructed. All the investigations concern only flows with a single temperature field. Copyright © 1996 …

Fluid Flow and Transfer ProcessesStress (mechanics)Mixture theoryPhysicsHeat mass transferTheoretical physicsField (physics)Differential equationVariational principleGeneralizationMechanical EngineeringMechanicsCondensed Matter PhysicsInternational Journal of Heat and Mass Transfer
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Ventilation-Perfusion Ratio in Perflubron During Partial Liquid Ventilation

2010

BACKGROUND: Functional magnetic resonance imaging (fMRI) of fluorine-19 allows for the mapping of oxygen partial pressure within perfluorocarbons in the alveolar space (Pao(2)). Theoretically, fMRI-detected Pao(2) can be combined with the Fick principle approach, i.e., a mass balance of oxygen uptake by ventilation and delivery by perfusion, to quantify the ventilation-perfusion ratio (Va/Q) of a lung region: The mixed venous blood and the inspiratory oxygen fraction, which are equal for all lung regions, are measured. In addition, the local expiratory oxygen fraction and the end capillary oxygen content, both of which may differ between the lung regions, are calculated using the fMRI-detec…

Fluorine RadioisotopesLiquid VentilationSwineContrast Mediachemistry.chemical_elementVentilation/perfusion ratioOxygenFick principleBody Temperaturechemistry.chemical_compoundVentilation-Perfusion RatioAnimalsHumansMedicineComputer SimulationFluorocarbonsbusiness.industryPerflubronHemodynamicsOxygen transportPartial pressureMagnetic Resonance ImagingHydrocarbons BrominatedOxygenPulmonary AlveoliAnesthesiology and Pain MedicinechemistryAnesthesiaBreathingPulmonary Diffusing CapacitybusinessNuclear medicineBlood Gas Monitoring TranscutaneousPerfusionAlgorithmsAnesthesia & Analgesia
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Dialogue through the eyes: Exploring teachers’ focus of attention during educational dialogue

2020

Abstract This study explored teachers’ focus of attention during educational dialogue. Teachers’ focus of attention was recorded in 54 Grade 1 classrooms using Tobii Pro Glasses 2 mobile eye-tracking device. From the video recordings, episodes of educational dialogue were identified and categorised by quality. Teacher’s focus of attention on students was examined during the dialogue episodes. Results showed that teachers allocated their attention relatively unevenly among the students. More students got visual attention during high-quality educational dialogue than during moderate-quality dialogue. This study provides insight into the quality of educational dialogue by combining assessment …

Focus (computing)4. Educationmedia_common.quotation_subject05 social sciences050301 educationEducationInformationSystems_MODELSANDPRINCIPLESComputingMilieux_COMPUTERSANDEDUCATIONMathematics educationVisual attention0501 psychology and cognitive sciencesQuality (business)Psychology0503 education050104 developmental & child psychologymedia_commonInternational Journal of Educational Research
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Designing theme-based tabletop exercise for identifying and dealing with coordination problems in emergencies

2016

Tabletop exercises (TTXs) are used to train managers and other actors to deal with emergencies. These exercises that focus on the organisational coordination are planned and controlled by exercise managers through scenarios with predetermined events that participants discuss and act upon. Such exercises may lead to actors being ill prepared to deal with dynamic and emergent situations and problems. To address this knowledge gap, we apply an action design research approach to develop a TTX structured around non-sequential themes instead of predetermined events, thus allowing the participants to identify their own problems during the exercise. Our research contributes to existing knowledge by…

Focus (computing)EngineeringKnowledge managementEmergency managementbusiness.industry05 social sciencesDesign elements and principles02 engineering and technology020204 information systems0502 economics and business0202 electrical engineering electronic engineering information engineeringEmergency MedicineInformation systemAction design researchAction researchbusinessSet (psychology)Theme (computing)050203 business & managementInternational Journal of Emergency Management
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On Human–Computer Interaction in Brain–Computer Interfaces

2014

In this chapter, theoretical reflections on human–computer interaction in brain–computer interfaces (BCIs) are combined with the results of an empirical investigation concerning non-invasive EEG-based BCI users’ experiences with this technology. After a short overview of transhumanist visions in the field of neurotechnology this text discusses some anthropological positions concerning interaction between man and technical devices. The focus will be on the concept of “transparency”. Then some empirical results of a pilot study which investigated BCI users’ experiences concerning human–computer interaction in BCI use are presented and discussed against the anthropological background.

Focus (computing)InformationSystems_MODELSANDPRINCIPLESInformationSystems_INFORMATIONINTERFACESANDPRESENTATION(e.g.HCI)Human–computer interactionNeurotechnologyComputer scienceTransparency (behavior)Field (computer science)Brain–computer interface
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CONTINUA LA QUERELLE GIURISPRUDENZIALE SUGLI EX LETTORI DI LINGUA STRANIERA

2019

L’articolo analizza l’evoluzione della giurisprudenza multilivello sul rapporto di lavoro degli ex lettori di lingua straniera, oggi collaboratori linguistici: dopo una ricostruzione diacronica della legislazione di riferimento, l’A. sottolinea come la giurisprudenza – alla luce dei principi di libera circolazione e parità di trattamento – abbia arginato le discriminazioni di cui sono stati ripetutamente vittime gli ex lettori in ragione di un quadro normativo frammentario e disorganico. Infine, il saggio si sofferma sul più recente indirizzo di legittimità, che sulla base di un’interpretazione estensiva del dettato normativo ha equiparato il trattamento retributivo dei lettori stabilizzati…

Foreign language readers – foreign language collaborators – non-discrimination principle – freedom of movement – extensive interpretationSettore IUS/07 - Diritto Del LavoroLettori di lingua straniera – collaboratori linguistici – non discriminazione – libera circolazione – interpretazione analogica
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