Search results for "Scaling"

showing 10 items of 754 documents

Superconducting size effect in thin films under electric field: Mean-field self-consistent model

2019

We consider effects of an externally applied electrostatic field on superconductivity, self-consistently within a BCS mean field model, for a clean 3D metal thin film. The electrostatic change in superconducting condensation energy scales as $\mu^{-1}$ close to subband edges as a function of the Fermi energy $\mu$, and follows 3D scaling $\mu^{-2}$ away from them. We discuss nonlinearities beyond gate effect, and contrast results to recent experiments.

---Josephson effectsuprajohtavuusFOS: Physical sciences02 engineering and technology01 natural sciencessuprajohteetSuperconductivity (cond-mat.supr-con)superconducting phase transitionElectric fieldCondensed Matter::Superconductivity0103 physical sciencesThin film010306 general physicsScalingCondensed Matter::Quantum GasesSuperconductivityPhysicsCondensed matter physicsCondensed Matter - SuperconductivityFermi energy021001 nanoscience & nanotechnologyMean field theorythin filmsmesoscopicsohutkalvot0210 nano-technologyEnergy (signal processing)Physical Review B
researchProduct

Derivation of a Homogenized Two-Temperature Model from the Heat Equation

2014

This work studies the heat equation in a two-phase material with spherical inclusions. Under some appropriate scaling on the size, volume fraction and heat capacity of the inclusions, we derive a coupled system of partial differential equations governing the evolution of the temperature of each phase at a macroscopic level of description. The coupling terms describing the exchange of heat between the phases are obtained by using homogenization techniques originating from [D. Cioranescu, F. Murat: Coll\`ege de France Seminar vol. 2. (Paris 1979-1980) Res. Notes in Math. vol. 60, pp. 98-138. Pitman, Boston, London, 1982.]

01 natural sciencesHomogenization (chemistry)Heat capacity010305 fluids & plasmasTwo temperatureMathematics - Analysis of PDEsThermal nonequilibrium models0103 physical sciencesFOS: Mathematics[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]0101 mathematicsScalingMSC 35K05 35B2776T05 (35Q79 76M50)35K05 35B27 76T05 (35Q79 76M50)MathematicsNumerical AnalysisHomogenizationPartial differential equationInfinite diffusion limitApplied MathematicsHeat equationMathematical analysis010101 applied mathematicsComputational MathematicsThermal non-equilibrium modelsModeling and SimulationVolume fractionHeat equationAnalysisAnalysis of PDEs (math.AP)
researchProduct

Scaling up electrically synchronized spin torque oscillator networks

2018

AbstractSynchronized nonlinear oscillators networks are at the core of numerous families of applications including phased array wave generators and neuromorphic pattern matching systems. In these devices, stable synchronization between large numbers of nanoscale oscillators is a key issue that remains to be demonstrated. Here, we show experimentally that synchronized spin-torque oscillator networks can be scaled up. By increasing the number of synchronized oscillators up to eight, we obtain that the emitted power and the quality factor increase linearly with the number of oscillators. Even more importantly, we demonstrate that the stability of synchronization in time exceeds 1.6 millisecond…

010302 applied physicsPhysicsMultidisciplinaryPhased arrayOscillationlcsh:Rlcsh:Medicine02 engineering and technology021001 nanoscience & nanotechnologyTopology01 natural sciencesStability (probability)SynchronizationArticlePower (physics)Quality (physics)Neuromorphic engineering0103 physical scienceslcsh:Q0210 nano-technologylcsh:ScienceScalingScientific Reports
researchProduct

Towards highly accurate ab initio thermochemistry of larger systems: benzene.

2011

The high accuracy extrapolated ab initio thermochemistry (HEAT) protocol is applied to compute the total atomization energy (TAE) and the heat of formation of benzene. Large-scale coupled-cluster calculations with more than 1500 basis functions and 42 correlated electrons as well as zero-point energies based on full cubic and (semi)diagonal quartic force fields obtained with the coupled-cluster singles and doubles with perturbative treatment of the triples method and atomic natural orbital (ANO) triple- and quadruple-zeta basis sets are presented. The performance of modifications to the HEAT scheme and the scaling properties of its contributions with respect to the system size are investiga…

010304 chemical physicsChemistryAb initioGeneral Physics and AstronomyBasis function010402 general chemistry01 natural sciences7. Clean energyStandard enthalpy of formation0104 chemical sciencesChemical thermodynamicsAb initio quantum chemistry methodsQuartic function0103 physical sciencesThermochemistryPhysics::Chemical PhysicsPhysical and Theoretical ChemistryAtomic physicsScalingThe Journal of chemical physics
researchProduct

Down-Scaling Modis Vegetation Products with Landsat GAP Filled Surface Reflectance in Google Earth Engine

2020

High spatial resolution vegetation products are fundamental in different fields, such as improving the understanding of crop seasonality at regional scales. Here, two new vegetation products such as the Leaf Area Index (LAI) and the Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) are downscaled at continental scales. A novel HIghly Scalable Temporal Adaptive Reflectance Fusion Model (HIS-TARFM) is used to generate the gap-free time series of Landsat surface reflectance data by fusing MODIS and Landsat reflectance for the contiguous United States. An artificial neural network is trained to capture the relationship between the gap free Landsat surface reflectance and the MODI…

010504 meteorology & atmospheric sciences0208 environmental biotechnology02 engineering and technologyDown scalingVegetationSeasonalitymedicine.disease01 natural sciencesReflectivity020801 environmental engineeringPhotosynthetically active radiationHigh spatial resolutionmedicineEnvironmental scienceLeaf area indexImage resolution0105 earth and related environmental sciencesRemote sensingIGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium
researchProduct

The impact of climate change on extreme precipitation in Sicily, Italy

2018

Increasing precipitation extremes are one of the possible consequences of a warmer climate. These may exceed the capacity of urban drainage systems, and thus impact the urban environment. Because short-duration precipitation events are primarily responsible for flooding in urban systems, it is important to assess the response of extreme precipitation at hourly (or sub-hourly) scales to a warming climate. This study aims to evaluate the projected changes in extreme rainfall events across the region of Sicily (Italy) and, for two urban areas, to assess possible changes in Depth-Duration-Frequency (DDF) curves. We used Regional Climate Model outputs from Coordinated Regional Climate Downscalin…

010504 meteorology & atmospheric sciences0208 environmental biotechnologyClimate change02 engineering and technology01 natural sciences11. SustainabilityClimate changePrecipitationDrainageClimate change; DDF; EURO-CORDEX; Extreme precipitation; RCM; Temporal downscaling; Water Science and Technology0105 earth and related environmental sciencesWater Science and TechnologyExtreme precipitationRain gaugeFlooding (psychology)Representative Concentration PathwaysTemporal downscaling020801 environmental engineering13. Climate actionClimatologyRCMEnvironmental scienceDDFClimate modelEURO-CORDEXDownscalingHydrological Processes
researchProduct

Downscaling of American National Aeronautics and Space Administration (NASA) daily air temperature in Sicily, Italy, and effects on crop reference ev…

2018

Abstract Air temperature (Ta) is one of the key factors in agro-hydrological studies including estimation of crop reference evapotranspiration (ET0), which is crucial for irrigation water management and sustainability of agro-ecosystem productivity. Because direct measurements of ET0 are difficult, expensive and time consuming, the use of physically based or empirical approaches linked to meteorological information is often preferred. The Prediction of Worldwide Energy Resource project developed by the American National Aeronautics and Space Administration (POWER-NASA) provides daily meteorological information on a 1° latitude by 1° longitude grid. Despite the poor spatial resolution charac…

010504 meteorology & atmospheric sciencesElevationSoil ScienceLapse rateHargreaves equation04 agricultural and veterinary sciences01 natural sciencesLatitudeAeronauticsEvapotranspirationTurc equationWeather dat040103 agronomy & agriculture0401 agriculture forestry and fisheriesEnvironmental scienceSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliPenman–Monteith equationDigital elevation modelLongitudeAgronomy and Crop Science0105 earth and related environmental sciencesDownscalingPOWER-NASAWater Science and TechnologyEarth-Surface Processes
researchProduct

Empirical and physical estimation of Canopy Water Content from CHRIS/PROBA data

2013

20 páginas, 4 tablas, 7 figuras.

010504 meteorology & atmospheric sciencesMean squared errorScience0211 other engineering and technologies02 engineering and technologyCHRIS/PROBA01 natural sciencescanopy water content;model inversion;neural networks;look up tables;empirical up-scalingmodel inversionEmpirical up-scalingAtmospheric radiative transfer codeslook up tablesRadiative transferModel inversion021101 geological & geomatics engineering0105 earth and related environmental sciencesMathematicsRemote sensingArtificial neural networkCanopy water contentQHyperspectral imagingInversion (meteorology)Sigmoid functionSpectral bandsempirical up-scaling15. Life on landneural networks[SDE]Environmental SciencesGeneral Earth and Planetary SciencesLook up tablescanopy water contentNeural networkscanopy water content; model inversion; neural networks; look up tables; empirical up-scaling; CHRIS/PROBA
researchProduct

The Making of the New European Wind Atlas - Part 2: production and evaluation

2020

This is the second of two papers that document the creation of the New European Wind Atlas (NEWA). In Part 1, we described the sensitivity experiments and accompanying evaluation done to arrive at the final mesoscale model setup used to produce the mesoscale wind atlas. In this paper, Part 2, we document how we made the final wind atlas product, covering both the production of the mesoscale climatology generated with the Weather Research and Forecasting (WRF) model and the microscale climatology generated with the Wind Atlas Analysis and Applications Program (WAsP). The paper includes a detailed description of the technical and practical aspects that went into running the mesoscale simulati…

010504 meteorology & atmospheric sciencesMeteorology020209 energyMesoscale meteorologyTerrainParameterization02 engineering and technology01 natural sciencesWind speedWind speed0202 electrical engineering electronic engineering information engineeringWind atlasData flow modelSurface wind0105 earth and related environmental sciences:Enginyeria agroalimentària::Ciències de la terra i de la vida::Climatologia i meteorologia [Àrees temàtiques de la UPC]lcsh:QE1-996.5Física atmosféricalcsh:GeologyWeather Research and Forecasting ModelEnvironmental scienceNew European Wind AtlasSimulacio per ordinadorComputational methods in engineeringDownscalingModel
researchProduct

Modified climate with long term memory in tree ring proxies

2015

ABSTRACT : A contribution to the PAGES Asia2k Working Group. ABSTRACT: Long term memory (LTM) scaling behavior in worldwide tree ring proxies and subsequent climate reconstructions is analyzed for and compared with the memory structure inherent to instrumental temperature and precipitation data. Detrended fluctuation analysis is employed to detect LTM and its scaling exponent a is used to evaluate LTM. The results show that temperature and precipitation reconstructions based on ring width measurements (mean \alpha =0.8) contain more memory than records based on maximum latewood density (mean \alpha =0.7). Both exceed the memory inherent to regional instrumental data (\alpha =0.6 for tempera…

010504 meteorology & atmospheric sciencesRenewable Energy Sustainability and the EnvironmentLong-term memoryPublic Health Environmental and Occupational HealthExtreme events01 natural sciencesProxy (climate)13. Climate actionClimatology0103 physical sciencesDendrochronologyDetrended fluctuation analysisEnvironmental scienceStatistical analysisCold period010306 general physicsScaling0105 earth and related environmental sciencesGeneral Environmental ScienceEnvironmental Research Letters
researchProduct