Search results for "FrACT"

showing 10 items of 6229 documents

The Electrical Properties of Ba1-ySryZrxTi1-xO3Solid Solution

2011

A lead-free solid solution Ba0.80Sr0.20Ti0.75Zr0.25O3 was prepared by a conventional technology. The structure and morphology of investgated samples were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The studies of electric conductivity were performed depending on temperature and frequency of electric measuring field. The activation energy was calculated from the Arrhenius plots.

Arrhenius equationDiffractionMaterials scienceMorphology (linguistics)Field (physics)Scanning electron microscopeAnalytical chemistryActivation energyCondensed Matter PhysicsElectronic Optical and Magnetic Materialssymbols.namesakeElectrical resistivity and conductivitysymbolsSolid solutionFerroelectrics
researchProduct

New Objective Refraction Metric Based on Sphere Fitting to the Wavefront

2017

Purpose. To develop an objective refraction formula based on the ocular wavefront error (WFE) expressed in terms of Zernike coefficients and pupil radius, which would be an accurate predictor of subjective spherical equivalent (SE) for different pupil sizes.Methods. A sphere is fitted to the ocular wavefront at the center and at a variable distance,t. The optimal fitting distance,topt, is obtained empirically from a dataset of 308 eyes as a function of objective refraction pupil radius,r0, and used to define the formula of a new wavefront refraction metric (MTR). The metric is tested in another, independent dataset of 200 eyes.Results. For pupil radiir0≤2 mm, the new metric predicts the equ…

Article SubjectMean squared errorZernike polynomials01 natural sciences010309 optics03 medical and health sciencessymbols.namesake0302 clinical medicinelcsh:Ophthalmology0103 physical sciencesMedicineComputer visionAdaptive opticsWavefrontbusiness.industryMathematical analysisFunction (mathematics)RadiusRefractionOphthalmologylcsh:RE1-994Metric (mathematics)030221 ophthalmology & optometrysymbolsArtificial intelligencebusinessResearch ArticleJournal of Ophthalmology
researchProduct

Localization Operators and an Uncertainty Principle for the Discrete Short Time Fourier Transform

2014

Localization operators in the discrete setting are used to obtain information on a signalffrom the knowledge on the support of its short time Fourier transform. In particular, the extremal functions of the uncertainty principle for the discrete short time Fourier transform are characterized and their connection with functions that generate a time-frequency basis is studied.

Article SubjectNon-uniform discrete Fourier transformDiscrete-time Fourier transformApplied Mathematicslcsh:MathematicsMathematical analysisShort-time Fourier transformlcsh:QA1-939Fractional Fourier transformDiscrete Fourier transform (general)symbols.namesakeFourier transformDiscrete sine transformDiscrete Fourier seriessymbolsAnalysisMathematicsAbstract and Applied Analysis
researchProduct

Imaging Quality of Bifocal Piggyback Intraocular Lens versus ReSTOR and TECNIS Multifocal Lenses

2009

Purpose The imaging quality provided by a piggyback integrated by a monofocal intraocular lens (IOL) + a bifocal IOL of zero power and +3.75 diopters of addition is compared with the optics quality of a simple multifocal IOL of the same power and addition. Methods The imaging quality was evaluated by determining the modulation transfer function (MTF), using an artificial eye simulating in vivo conditions of the anterior chamber, including an artificial cornea and a wet cell containing physiologic solution where the IOL was positioned. The MTFs of the bifocal piggyback for near and distance vision were measured, with pupil diameters of 3 and 5 mm, and compared with the MTFs of an equivalent …

Artificial corneaOptics and Photonicsmedicine.medical_specialtybusiness.product_categoryMaterials sciencemedicine.medical_treatmentVisual AcuityIntraocular lensEyeRefraction OcularPupil03 medical and health sciences0302 clinical medicineOptical transfer functionOphthalmologymedicineHumansMultifocal lensesDioptreLenses IntraocularDepth PerceptionStrehl ratioGeneral MedicineModels TheoreticalOphthalmologyImaging quality030221 ophthalmology & optometryArtificial Organsbusiness030217 neurology & neurosurgeryEuropean Journal of Ophthalmology
researchProduct

Statistical tools and artificial intelligence approaches to predict fracture in bulk metal forming

2007

Artificial intelligenceDuctile fractureStatistical approach
researchProduct

On the use of artificial intelligence tools for fracture forecast in cold forming operations

2006

Abstract The design of cold forming processes requires the availability of a procedure able to deal with the prevention of ductile fracture. In fact, the ability to predict fracture represents a powerful tool to improve the production quality in mechanical industry. In this paper, artificial intelligence (AI) techniques are applied to ductile fracture prediction in cold forming operations. The main advantage of the application of AI tools and in particular, of artificial neural networks (ANN), is the possibility to obtain a predictive tool with a wide applicability. The prediction results obtained in this paper fully demonstrate the usefulness of the proposed approach.

Artificial neural networkEngineeringArtificial intelligenceArtificial neural networkbusiness.industryDuctile fractureBulk formingMetals and AlloysIndustrial and Manufacturing EngineeringManufacturing engineeringComputer Science ApplicationsBulk formingModeling and SimulationForming process designCeramics and CompositesFracture (geology)Artificial intelligencebusinessCold formingProduction quality
researchProduct

Testing the shape-similarity hypothesis between partide-size distribution and water retention for sicilian soils

2012

Application of the Arya and Paris (AP) model to estimate the soil water retention curve requires a detailed description of the particlesize distribution (PSD) but limited experimental PSD data are generally determined by the conventional sieve-hydrometer (SH) method. Detailed PSDs can be obtained by fitting a continuous model to SH data or performing measurements by the laser diffraction (LD) method. The AP model was applied to 40 Sicilian soils for which the PSD was measured by both the SH and LD methods. The scale factor was set equal to 1.38 (procedure AP1) or estimated by a logistical model with parameters gathered from literature (procedure AP2). For both SH and LD data, procedure AP2 …

Arya and Paris modelSoil water retention curveLaser diffraction methodSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliParticle size distribution
researchProduct

Mu-tau neutrino refraction and collective three-flavor transformations in supernovae

2008

9 pages, 6 figures.-- PACS nrs.: 14.60.Pq; 97.60.Bw.-- ArXiv pre-print available at: http://arxiv.org/abs/0712.1137

AstrofísicaHistoryNuclear and High Energy PhysicsParticle physicsPhysics::Instrumentation and Detectors[SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]FlavourFOS: Physical sciencesAstrophysicsAstrophysics01 natural sciencesPartícules (Física nuclear)Education[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO]High Energy Physics - Phenomenology (hep-ph)Tau neutrino0103 physical sciencesRefraction (sound)010306 general physicsNeutrino oscillationPhysicsMuon010308 nuclear & particles physicsAstrophysics (astro-ph)High Energy Physics::PhenomenologySolar neutrino problemComputer Science ApplicationsSupernovaHigh Energy Physics - Phenomenology[PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph]Measurements of neutrino speedHigh Energy Physics::ExperimentNeutrinoElectron neutrino
researchProduct

Description of atmospheric conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS)

2012

Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargüe and averaged monthly models, the utility of the GDAS data is shown.

AstronomyAtmospheric modelAtmospheric monitoringAtmospheric sciencesCosmic Rays Shower01 natural scienceslaw.inventionData assimilationlawcosmic rays; extensive air showers; atmospheric monitoring; atmospheric modelsDEPENDENCEATMOSFERA (OBSERVAÇÃO)TEMPERATUREPhysics::Atmospheric and Oceanic PhysicsPhysicsHigh Energy Astrophysical Phenomena (astro-ph.HE)[PHYS]Physics [physics]Cascada atmosférica extensaOPTICAL DEPTH[SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]Astrophysics::Instrumentation and Methods for AstrophysicsPierre Auger ObservatoryAtmospheric temperatureRadiación cósmicaAtmosphere of EarthComputingMethodologies_DOCUMENTANDTEXTPROCESSINGRadiosondeFísica nuclearREFRACTIVE-INDEXAstrophysics - High Energy Astrophysical Phenomena[PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]MeteorologyAtmospheric MonitoringAstrophysics::High Energy Astrophysical PhenomenaFOS: Physical sciencesCosmic Rays ShowersEXTENSIVE AIR-SHOWERSCosmic RayAtmósferaWeather stationAtmospheric models0103 physical sciencesExtensive air showers010306 general physicsCosmic raysDETECTORCiencias ExactasPierre Auger ObservatoryAtmospheric models010308 nuclear & particles physicsFísicaAstronomy and Astrophysics13. Climate actionExperimental High Energy PhysicsEMISSION[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
researchProduct

"Table 24" of "Search for pairs of highly collimated photon-jets in $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector"

2018

Fraction of reconstructed photons with a value of shower shape variable $\Delta E$ lower than the threshold, for reconstructed photons originating from the decay $a\rightarrow 2\gamma$ with $m_a$ = 1 GeV.

Astrophysics::High Energy Astrophysical PhenomenaCategory fractionHigh Energy Physics::PhenomenologyHigh Energy Physics::Experiment$pp\rightarrow X \rightarrow aa \rightarrow 4\gamma$13000Photon-jet
researchProduct