Search results for "density [charge]"

showing 10 items of 318 documents

Traffic fundamentals for A22 Brenner freeway by microsimulation models.

La tesi di dottorato ha avuto come tema lo studio e l’applicazione di un modello di micro-simulazione del traffico in ambito autostradale. Essa si compone di quattro capitoli, con ognuno dei quali si è voluto sintetizzare e descrivere il lavoro di studio e ricerca svolto durante il suddetto corso di Dottorato di Ricerca. L’obiettivo principale del presente lavoro di tesi è stato quello di mettere a punto una metodologia finalizzata all’ottenimento delle relazioni fondamentali di deflusso in ambito autostradale attraverso il software di microsimulazione del traffico Aimsun. Come risulta infatti noto dalla letteratura scientifica, le relazioni fondamentali del deflusso sono utilizzate nel cam…

Traffic engineeringSpeed- density relationshipRoad infrastructure engineeringGenetic algorithmCalibrationTraffic engineering; Traffic microsimulation models; Road infrastructure engineering; Aimsun; Calibration; Genetic algorithm; Speed- density relationshipSettore ICAR/04 - Strade Ferrovie Ed AeroportiTraffic microsimulation modelAimsun
researchProduct

Stark ionization of atoms and molecules within density functional resonance theory

2013

We show that the energetics and lifetimes of resonances of finite systems under an external electric field can be captured by Kohn–Sham density functional theory (DFT) within the formalism of uniform complex scaling. Properties of resonances are calculated self-consistently in terms of complex densities, potentials, and wave functions using adapted versions of the known algorithms from DFT. We illustrate this new formalism by calculating ionization rates using the complex-scaled local density approximation and exact exchange. We consider a variety of atoms (H, He, Li, and Be) as well as the H2 molecule. Extensions are briefly discussed.

TunnelingFOS: Physical sciences02 engineering and technology01 natural sciences7. Clean energySettore FIS/03 - Fisica Della MateriaOpen quantum systemsComplex scalingPhysics - Chemical PhysicsIonizationElectric field0103 physical sciencesExcitationsPhysics::Atomic and Molecular ClustersMoleculeGeneral Materials SciencePhysical and Theoretical ChemistryPhysics::Chemical Physics010306 general physicsWave functionScalingSpectroscopyPhysicsChemical Physics (physics.chem-ph)Condensed Matter - Materials ScienceLasersAtoms in moleculesMaterials Science (cond-mat.mtrl-sci)021001 nanoscience & nanotechnologyResonancesDensity functional theoryLocal-density approximationAtomic physics0210 nano-technologyJournal of Physical Chemistry Letters
researchProduct

Food predictability determines space use of endangered vultures: implications for management of supplementary feeding.

2013

Understanding space use of free-living endangered animals is key to inform management decisions for conservation planning. Like most scavengers, vultures have evolved under a context of unpredictability of food resources (i.e. exploiting scattered carcasses that are intermittently available). However, the role of predictable sources of food in shaping spatial ecology of vultures has seldom been studied in detail. Here, we quantify the home range of the Egyptian vulture (Neophron percnopterus), a long-lived raptor which has experienced severe population decline throughout its range and is qualified as endangered worldwide. To this end six adults were tracked by satellite telemetry in Spain d…

Utilization distributionConservation of Natural ResourcesRange (biology)Home rangeVulture restaurantsEndangered speciesContext (language use)Utilization distributionConservationBirdsbiology.animalZoologiaSpatial ecologyAnimalsCarrionZoologíaFalconiformesVultureEcologybiologyEcologyAnimal FeedHome rangeGeographySpainNeophron percnopterusSatellite telemetryKernel density estimatorsResource utilization functions
researchProduct

Data for: Accurate representation of the distributions of the 3D Poisson-Voronoi typical cell geometrical features

2019

gvolume.txt contains the grid of points (xgrid.v) and the kernel density estimate (Epanechnikov kernel, cross validation bandwidth h=0.05) of volume of 1,000,000 Poisson-Voronoi typical cells ( intensity parameter lambda=1) evaluated in the grid points (y.v).gsurfacearea.txt contains the grid of points (xgrid.a) and the kernel density estimate (Epanechnikov kernel, cross validation bandwidth h=0.25) of surface area of 1,000,000 Poisson-Voronoi typical cells ( intensity parameter lambda=1) evaluated in the grid points (y.a).gnfaces.txt contains the absolute (nf) and relative frequencies (pf) of number of faces 1,000,000 Poisson-Voronoi typical cells ( intensity parameter lambda=1) THIS DATAS…

Voronoi DiagramDensity EstimationStatisticsFOS: MathematicsDistribution FunctionOtherInterdisciplinary sciencesGrain Size
researchProduct

Ageing of isotactic polypropylene due to morphology evolution, experimental limitations of realtime density measurements with a gradient column

2006

Abstract Ageing in crystalline polymers is responsible for the deterioration of physical properties leading, for example, to a decrease in toughness and to dimensional changes that are to some extent responsible for warpage and scrap production in injection molding. Since, it depends on the mutual transformation of stable and metastable phases, being always related to changes in morphological organization, it is here preferred to call it ‘Morphological ageing’. Although, one would expect the ageing regime to be determined by the complex morphology with amorphous phases of different mobility and eventually multiple crystalline phases, transformed into each other at an associated transition, …

Work (thermodynamics)ToughnessMaterials sciencePolymers and PlasticsLogarithmScatteringOrganic ChemistryMineralogyThermodynamicsDensity evolutionPost processingAmorphous solidMorphological ageingSuperposition principleSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialiAgeingMetastabilityMaterials Chemistry
researchProduct

Localized magnetic moments in the Heusler alloy Rh2MnGe

2009

X-ray magnetic circular dichroism (XMCD) of core-level absorption (x-ray absorption spectroscopy, XAS) spectra in the soft x-ray region has been measured for the ferromagnetic Heusler alloy Rh2MnGe at the Rh M3,2 and Mn L3,2 edges. The ratio of Rh and Mn spin moments amounts to 0.05 which is smaller than the ratio of 0.1 determined by a local density approximation electronic band structure calculation. We have found that the orbital moments of the Rh 4d and Mn 3d states are very small. The observed Rh 2p XAS spectrum can be understood on the basis of the Rh 3d partial density of unoccupied states as is typical for metals. The observed features of the Mn 2p XAS and XMCD spectra are dominated…

X-ray absorption spectroscopyAcoustics and UltrasonicsCondensed matter physicsAbsorption spectroscopyMagnetic momentMagnetic circular dichroismHeisenberg modelChemistryCondensed Matter PhysicsSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsCondensed Matter::Materials ScienceMagnetizationFerromagnetismCondensed Matter::Strongly Correlated ElectronsLocal-density approximationJournal of Physics D: Applied Physics
researchProduct

Modelling and prediction of perceptual segmentation

2017

While listening to music, we somehow make sense of a multiplicity of auditory events; for example, in popular music we are often able to recognize whether the current section is a verse or a chorus, and to identify the boundaries between these segments. This organization occurs at multiple levels, since we can discern motifs, phrases, sections and other groupings. In this work, we understand segment boundaries as instants of significant change. Several studies on music perception and cognition have strived to understand what types of changes are associated with perceptual structure. However, effects of musical training, possible differences between real-time and non real-time segmentation, and…

Ydinestimointirakennemusiikkiperceptual segmentation taskhavaitseminenmuutosmusical structurekuunteleminensegmentointimusiikintutkimusmusiikkitiedekernel density estimationnovelty detectionmusical featuresmusical training
researchProduct

Spectral density estimation for stationary stable random fields

1995

International audience

[ MATH ] Mathematics [math]Mathematical optimization[ STAT ] Statistics [stat][SPI] Engineering Sciences [physics][MATH] Mathematics [math]01 natural sciences[PHYS] Physics [physics][SPI]Engineering Sciences [physics]010104 statistics & probability[ SPI ] Engineering Sciences [physics]Applied mathematics[MATH]Mathematics [math]0101 mathematicsComputingMilieux_MISCELLANEOUSMathematics[PHYS]Physics [physics][ PHYS ] Physics [physics]Random fieldApplied MathematicsSpectral density estimation[STAT] Statistics [stat][STAT]Statistics [stat]010101 applied mathematicsDiscrete time and continuous timeVariable kernel density estimationKernel embedding of distributionsKernel (statistics)PeriodogramApplicationes Mathematicae
researchProduct

Solving chance constrained optimal control problems in aerospace via Kernel Density Estimation

2017

International audience; The goal of this paper is to show how non-parametric statistics can be used to solve some chance constrained optimization and optimal control problems. We use the Kernel Density Estimation method to approximate the probability density function of a random variable with unknown distribution , from a relatively small sample. We then show how this technique can be applied and implemented for a class of problems including the God-dard problem and the trajectory optimization of an Ariane 5-like launcher.

[ MATH.MATH-OC ] Mathematics [math]/Optimization and Control [math.OC]Mathematical optimizationControl and Optimizationchance constrained optimizationKernel density estimation0211 other engineering and technologiesProbability density function02 engineering and technology01 natural sciencesKernel Density Estimation010104 statistics & probability0101 mathematicsMathematics021103 operations researchApplied MathematicsConstrained optimizationTrajectory optimizationstochastic optimizationOptimal controlOptimal controlDistribution (mathematics)Aerospace engineeringControl and Systems EngineeringStochastic optimization[MATH.MATH-OC]Mathematics [math]/Optimization and Control [math.OC]Random variableSoftware
researchProduct

Computerized delimitation of odorant areas in gas-chromatography-olfactometry by kernel density estimation: Data processing on French white wines

2017

International audience; GC-O using the detection frequency method gives a list of odor events (OEs) where each OE is described by a linear retention index (LRI) and by the aromatic descriptor given by a human assessor. The aim of the experimenter is to gather OEs in a total olfactogram on which he tries to delimit odorant areas (OAs), then to compute each detection frequency. This paper proposes a computerized mathematical method based on kernel density estimation that makes up the total olfactogram as continuous and differentiable function from the OEs LRI only. The corresponding curve looks like a chromatogram, the peaks of which are potential OAs. The limits of an OA are the LRI of the t…

[ SDV.AEN ] Life Sciences [q-bio]/Food and NutritionKernel density estimation01 natural sciencesolfactogramAnalytical ChemistrySet (abstract data type)0404 agricultural biotechnologyStatisticsRange (statistics)Kernel densitu estimationSpectroscopyMathematicsContingency tableProcess Chemistry and Technology010401 analytical chemistry04 agricultural and veterinary sciencesdetection frequency method040401 food science0104 chemical sciencesComputer Science ApplicationsMaxima and minimaGC olphactometryKernel (statistics)Benchmark (computing)Kovats retention indexParzen-Rosenblatt[SDV.AEN]Life Sciences [q-bio]/Food and NutritionSoftware
researchProduct