Search results for "Moda"

showing 10 items of 1753 documents

Coupling of density wave oscillations in parallel channels with high order modal kinetics: application to BWR out of phase oscillations

2000

Abstract In this paper, we study the behavior of a system formed by two parallel channels coupled to a multimodal kinetics. The first problem that arises is the calculation of the reactivity coefficients for the higher modes. This problem is solved by means of the introduction of distribution factors for a given reactor region which depend on the involved modes. We have also performed a detailed analysis of the different instability types which can be obtained from the model changing the boundary conditions and the feedback gains of the fundamental and first harmonic modes.

PhysicsCouplingOut of phaseModalDistribution (mathematics)Nuclear Energy and EngineeringControl theoryKineticsBoundary value problemMechanicsInstabilityDensity wave theoryAnnals of Nuclear Energy
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Electrical analogous in viscoelasticity

2014

In this paper, electrical analogous models of fractional hereditary materials are introduced. Based on recent works by the authors, mechanical models of materials viscoelasticity behavior are firstly approached by using fractional mathematical operators. Viscoelastic models have elastic and viscous components which are obtained by combining springs and dashpots. Various arrangements of these elements can be used, and all of these viscoelastic models can be equivalently modeled as electrical circuits, where the spring and dashpot are analogous to the capacitance and resistance, respectively. The proposed models are validated by using modal analysis. Moreover, a comparison with numerical expe…

PhysicsNumerical AnalysisEigenvalues analysiEigenvalues analysis Fractional calculus Fractional capacitor Viscoelastic modelsApplied MathematicsModal analysisMathematical analysisFinite-difference time-domain methodViscoelastic modelFractional calculuDashpotViscoelasticityFractional calculuslaw.inventionMathematical OperatorsFractional capacitorSettore ING-IND/31 - ElettrotecnicaSettore MAT/08 - Analisi NumericaSpring (device)lawModeling and SimulationElectrical networkCalculusSettore ICAR/08 - Scienza Delle Costruzioni
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Experimental observation of modal attraction in optical fibers

2002

We investigate experimentally nonlinear optical attractors based on four-photon mixing interaction of counterpropagating waves in optical fibers.

PhysicsOptical fiberComputer simulationbusiness.industryCross-phase modulationPhysics::OpticsAttractionlaw.inventionOpticsModallawBrillouin scatteringAttractorPhysics::Atomic PhysicsbusinessMixing (physics)Nonlinear Guided Waves and Their Applications
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Modal attraction on low order modes by Kerr effect in a graded refractive index multimode fiber

2018

Modal attraction towards low order modes in a GRIN multimode fiber was experimentally observed at high power and characterized, thus enriching the dynamics of the Kerr self-cleaning effect leading to quasi fundamental mode generation.

Physics[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics]Multi-mode optical fiberKerr effectoptical polarizationbusiness.industryPhysics::OpticsOrder (ring theory)02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesAttractionmultimode fibersPower (physics)multimode fibers; Kerr effect; optical polarizationModalOpticsKerr effect0103 physical sciences010306 general physics0210 nano-technologybusinessRefractive indexComputingMilieux_MISCELLANEOUS
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Solving the Cut-Off Wave Numbers in Partially filled Rectangular Waveguides with Ferrite by the Cauchy Integral Method

2005

The modal analysis of the off-centered rectangular waveguide loaded with a vertical slab of ferrite material, biased in the y-direction by a DC magnetic field, leads to the resolution of a transcendent equation whose infinite solutions are the TE/sub m0/ cutoff wave numbers in the guide. The method based on the Cauchy integral (Delvest L.M. and Lyness, J.N., 1967) is becoming very popular for solving such equations. This powerful method is described for solving the propagation constant in a partially ferrite filled waveguide. The method is used to calculate the propagation constant of the fundamental TE mode for some configurations used in the literature about ferrites. Results obtained in …

Physicsbusiness.industryModal analysisMathematical analysisIntegral equationlaw.inventionTransverse modeOpticslawFerrite (magnet)WavenumberPropagation constantbusinessWaveguideCauchy's integral formula2005 IEEE Antennas and Propagation Society International Symposium
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Impact of internal curvature gradient on the power and accommodation of the crystalline lens

2017

Human crystalline lens has a layered, shell-like structure with the refractive index increasing from cortex to nucleus (gradient index or GRIN structure). Moreover, every iso-indicial layer has a certain curvature which also varies from cortex to nucleus, with a gradient of curvature (G). In the present manuscript, the role of G on the lens power is investigated along with its implications regarding the lens paradox (change of lens power with age) and intra-capsular accommodation mechanism (larger than expected changes of lens power during accommodation compared to a homogenous lens). To this end, a simplified formulation of paraxial lens power based on thin lens approximation is developed …

Physics::OpticsAstrophysics::Cosmology and Extragalactic AstrophysicsCurvature01 natural sciences010305 fluids & plasmas010309 opticsOpticsThin lens0103 physical sciencesmedicineGRIN lensPhysicsbusiness.industryInternal curvaturesParaxial approximationAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsPower (physics)Lens power Lens accommodationmedicine.anatomical_structureLens (anatomy)Gradient-index opticsbusinessAccommodationRefractive indexOptica
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Interictal cardiorespiratory variability in temporal lobe and absence epilepsy in childhood

2015

It is well known that epilepsy has a profound effect on the autonomic nervous system, especially on the autonomic control of heart rate and respiration. This effect has been widely studied during seizure activity, but less attention has been given to interictal (i.e. seizure-free) activity. The studies that have been done on this topic, showed that heart rate and respiration can be affected individually, even without the occurrence of seizures. In this work, the interactions between these two individual physiological variables are analysed during interictal activity in temporal lobe and absence epilepsy in childhood. These interactions are assessed by decomposing the predictive information …

PhysiologyInformation Theory02 engineering and technologyElectroencephalographyMultimodal Imaging01 natural sciencesAutonomic controlElectrocardiographyEpilepsy0302 clinical medicineHeart RateHeart rate variabilityChildmedicine.diagnostic_testSISTARespirationheart rate variabilityElectroencephalographySignal Processing Computer-Assistedtemporal lobe epilepsy3. Good healthabsence epilepsyCardiologyPsychologymedicine.medical_specialty0206 medical engineeringBiophysicsBiomedical EngineeringTemporal lobe03 medical and health sciencesInternal medicinePhysiology (medical)0103 physical sciencesRespirationHeart ratemedicineHumansIctal010306 general physicsinformation dynamicbusiness.industryCardiorespiratory fitnessmedicine.disease020601 biomedical engineeringAutonomic nervous systemEpilepsy AbsenceEpilepsy Temporal LobeBiophysicSettore ING-INF/06 - Bioingegneria Elettronica E InformaticaepilepsyTransfer entropybusinessNeuroscience030217 neurology & neurosurgery
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I know what i like when i see it:Likability is distinct from pleasantness since early stages of multimodal emotion evaluation

2021

Liking and pleasantness are common concepts in psychological emotion theories and in everyday language related to emotions. Despite obvious similarities between the terms, several empirical and theoretical notions support the idea that pleasantness and liking are cognitively different phenomena, becoming most evident in the context of emotion regulation and art enjoyment. In this study it was investigated whether liking and pleasantness indicate behaviourally measurable differences, not only in the long timespan of emotion regulation, but already within the initial affective responses to visual and auditory stimuli. A cross-modal affective priming protocol was used to assess whether there i…

PleasureMultidisciplinarymieltymyksetEmotionsaistithavaintopsykologiahavainnottunteetPleasure/physiologyEmotions/physiologyAuditory PerceptionReaction TimemultimodaalisuusLanguage
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Interweaving visual and audio-haptic augmented reality for urban exploration

2018

While ordinary touchscreen-based interfaces on urban explorer applications draw much of a user's attention onto the screen, visual and audio-haptic augmented reality interfaces have emerged as the two main streams for enabling direct focus on the surroundings. However, neither interface alone satisfies users in the highly dynamic urban environment. This research investigates how the two complementary augmentation can coexist on one system and how people adapt to the situation by selecting the more suitable interface. A prototype was deployed in a field experiment in which participants explored points of interest in an urban environment with both interfaces. The engagement with the surroundi…

Point of interestComputer scienceInterface (computing)02 engineering and technologyAugmented realitylaw.inventionMultimodal interactionTouchscreenlawHuman–computer interaction11. SustainabilitySituated0202 electrical engineering electronic engineering information engineeringAudio-haptic interfaceUrban exploration0501 psychology and cognitive sciences050107 human factorsHaptic technologyta113Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniFocus (computing)Point (typography)Settore INF/01 - Informatica05 social sciences020201 artificial intelligence & image processingAugmented reality
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A wearable multimodal interface for exploring urban points of interest

2015

Locating points of interest (POIs) in cities is typically facilitated by visual aids such as paper maps, brochures, and mobile applications. However, these techniques require visual attention, which ideally should be on the surroundings. Non-visual techniques for navigating towards specific POIs typically lack support for free exploration of the city or more detailed guidance. To overcome these issues, we propose a multimodal, wearable system for alerting the user of nearby recommended POIs. The system, built around a tactile glove, provides audio-tactile cues when a new POI is in the vicinity, and more detailed information and guidance if the user expresses interest in this POI. We evaluat…

Point of interestComputer scienceInterface (computing)Wearable computer02 engineering and technologycomputer.software_genreAuditory iconsField (computer science)Multimodal interactionMultimodal interactionHuman–computer interaction11. SustainabilityWearable computing0202 electrical engineering electronic engineering information engineeringVisual attention0501 psychology and cognitive sciencesBaseline (configuration management)050107 human factorsta113Settore ING-INF/05 - Sistemi Di Elaborazione Delle InformazioniMultimediaSettore INF/01 - InformaticaTactile feedback05 social sciences020207 software engineeringAuditory iconCultural heritagecomputer
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