Search results for "SIMULATION"

showing 10 items of 5095 documents

Measurements of the tau polarisation in Z0 decays

1995

A sample of Z0→τ+τ- events observed in the DELPHI detector at LEP in 1991 and 1992 is analysed to measure the τ polarisation in the exclusive decay channels {Mathematical expression}, {Mathematical expression}, πν, ρν and a1ν. The τ polarisation is also measured with an inclusive hadronic analysis which benefits from a higher efficiency and a better systematic precision than the use of the exclusive decay modes. The results have been combined with those published on the 1990 data. A measurement of the τ polarisation as a function of production angle yields the values for the mean τ polarisation 〈P〉τ=-0.148±0.022 and for the Z0 polarisation PZ=-0.136±0.027. These results are used to determin…

Particle physicsPOLARIZATIONPhysics and Astronomy (miscellaneous)LUND MONTE-CARLOElectron–positron annihilationHadronLEP-SLC ENERGIESElectron01 natural sciencesPartícules (Física nuclear)JET FRAGMENTATIONPARAMETERSNuclear physicsPHYSICSBHABHA SCATTERINGZ-RESONANCE0103 physical sciencesradiative correction[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONS010306 general physicsEngineering (miscellaneous)Detectors de radiacióBhabha scatteringDELPHIPhysics010308 nuclear & particles physicsDetectortau polarizationPolarization (waves)LARGE ELECTRON POSITRON COLLIDERUniversality (dynamical systems)Z resonanceLUND MONTE-CARLO; LEP-SLC ENERGIES; RADIATIVE-CORRECTIONS; BHABHA SCATTERING; JET FRAGMENTATION; Z-RESONANCE; POLARIZATION; PHYSICS; SIMULATION; PARAMETERSSIMULATIONPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSHigh Energy Physics::ExperimentDELPHI; tau polarization; radiative correction; Z resonanceParticle Physics - ExperimentLepton
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A measurement of the photon structure function F-2(gamma) at an average Q(2) of 12 GeV2/c(4)

1995

The hadronic photon structure function F_{2}^{gamma} has been measured in the Q^{2} range from 4 to 30~GeV^2/c^{4} and down to x values of order 0.001, using data taken with the DELPHI detector at LEP between 1991 and 1993. A comparison is made with several F_{2}^{gamma} parameterizations with special emphasis on their low x behaviour. A result on the Q^{2} evolution of F_{2}^{gamma} is presented.

Particle physicsPhotonPhysics and Astronomy (miscellaneous)LEP; DELPHI; hadronic photon structureHadronMONTE-CARLO SIMULATIONStructure (category theory)01 natural sciencesC-4Partícules (Física nuclear)JET FRAGMENTATIONlaw.inventionQ2Nuclear physicsMONTE-CARLO SIMULATION; STRUCTURE-FUNCTION F2; JET FRAGMENTATION; E+E-PHYSICS; QCD; Q2; SCATTERING; ORDERlaw0103 physical sciencesRange (statistics)SCATTERINGhadronic photon structure010306 general physicsDELPHIQuantum chromodynamicsPhysicsE+E-PHYSICS010308 nuclear & particles physicsScatteringEmphasis (telecommunications)DetectorOrder (ring theory)ORDERLEPQCDLARGE ELECTRON POSITRON COLLIDERPhoton structure functionPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIMass spectrumPARTICLE PHYSICSFísica nuclearSTRUCTURE-FUNCTION F2
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Testing charged current quasi-elastic and multinucleon interaction models in the NEUT neutrino interaction generator with published datasets from the…

2016

There has been a great deal of theoretical work on sophisticated charged current quasi-elastic (CCQE) neutrino interaction models in recent years, prompted by a number of experimental results that measured unexpectedly large CCQE cross sections on nuclear targets. As the dominant interaction mode at T2K energies, and the signal process in oscillation analyses, it is important for the T2K experiment to include realistic CCQE cross section uncertainties in T2K analyses. To this end, T2K’s Neutrino Interaction Working Group has implemented a number of recent models in NEUT, T2K’s primary neutrino interaction event generator. In this paper, we give an overview of the models implemented and pres…

Particle physicsPhysics::Instrumentation and DetectorsC-12Astronomy & AstrophysicsMASS7. Clean energy01 natural sciencesPhysics Particles & FieldsMiniBooNENuclear physics0103 physical sciencesMINERνAMuon neutrino010306 general physicsNeutrino oscillationEvent generatorPhysicsScience & TechnologyMuonDELTA010308 nuclear & particles physicsPhysicsT2K experimentNUCLEUS SCATTERINGPhysical SciencesSIMULATIONHigh Energy Physics::ExperimentNeutrino
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LeptonInjector and LeptonWeighter: A neutrino event generator and weighter for neutrino observatories

2021

We present a high-energy neutrino event generator, called LeptonInjector, alongside an event weighter, called LeptonWeighter. Both are designed for large-volume Cherenkov neutrino telescopes such as IceCube. The neutrino event generator allows for quick and flexible simulation of neutrino events within and around the detector volume, and implements the leading Standard Model neutrino interaction processes relevant for neutrino observatories: neutrino-nucleon deep-inelastic scattering and neutrino-electron annihilation. In this paper, we discuss the event generation algorithm, the weighting algorithm, and the main functions of the publicly available code, with examples.

Particle physicsPhysics::Instrumentation and DetectorsComputer scienceAstrophysics::High Energy Astrophysical PhenomenaFOS: Physical sciencesGeneral Physics and AstronomyCHERENKOV LIGHT YIELDWeighting01 natural sciencesHigh Energy Physics - Experiment010305 fluids & plasmasStandard ModelHigh Energy Physics - Experiment (hep-ex)Neutrino interactionHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciences010306 general physicsCherenkov radiationEvent generatorEvent generator; Neutrino generator; Neutrino interaction; Neutrino simulation; WeightingGenerator (computer programming)hep-exEvent (computing)ICEHigh Energy Physics::PhenomenologyDetectorhep-phComputational Physics (physics.comp-ph)Quantitative Biology::GenomicsHigh Energy Physics - Phenomenologyphysics.comp-phHardware and ArchitectureHigh Energy Physics::ExperimentNeutrino simulationNeutrino generatorEvent generatorNeutrinoPhysics - Computational PhysicsLeptonComputer Physics Communications
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Fitting particle size distribution models to data from Burundian soils for the BEST procedure and other purposes

2009

Testing the Beerkan Estimation of Soil Transfer (BEST) soil particle size distribution (PSD) model is necessary to evaluate the applicability of the BEST procedure for characterising soil hydraulics. In this investigation, the fitting performance of the BEST PSD model was tested using a database of 114 Burundian soils with 14 measured particle size fractions for each soil sample, and also by considering a reduced number of measured particle size fractions for a sample. The fitting performance of the model developed by Fredlund et al. (2000) (FR model) was also considered for comparative purposes. On average, the BEST model yielded satisfactory results (i.e., mean relative error, E r ¯ = 3.9…

Particle-size distributionSoil textureBurundiSimulation modelingSoil ScienceDistribution (mathematics)Soil hydraulic propertieControl and Systems EngineeringApproximation errorParticle-size distribution modelSoil classificationStatisticsSoil waterParticle-size distributionSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliSize fractionsParticle sizeAgronomy and Crop ScienceFood ScienceMathematicsBiosystems Engineering
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General Introduction to Computer Simulation Methods

1986

Computer simulation methods are now an established tool in many branches of science. The motivation for computer simulations of physical systems are manifold. One of the main motivations is that one eliminates approximations with computer simulations. Usually to treat a problem analytically (if it can be done at all) one needs to resort to some kind of approximation; for exam- ple a mean-field-type approximation. With a computer simulation we have the ability to study systems not yet tractable with analytical methods. The computer simulation approach allows one to study complex systems and gain insight into their behaviour. Indeed, the complexity can go far beyond the reach of present analy…

Partition function (quantum field theory)Theoretical computer sciencelawComputer sciencePhase spaceComplex systemPhysical systemManifold (fluid mechanics)Simulation methodslaw.invention
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Desipramine induces disorder in cholesterol-rich membranes:implications for viral trafficking

2009

In this study, the effect of desipramine (DMI) on phospholipid bilayers and parvoviral entry was elucidated. In atomistic molecular dynamics simulations, DMI was found to introduce disorder in cholesterol-rich phospholipid bilayers. This was manifested by a decrease in the deuterium order parameter S(CD) as well as an increase in the membrane area. Disordering of the membrane suggested DMI to destabilize cholesterol-rich membrane domains (rafts) in cellular conditions. To relate the raft disrupting ability of DMI with novel biological relevance, we studied the intracellular effect of DMI using canine parvovirus (CPV), a virus known to interact with endosomal membranes and sphingomyelin, as …

Parvovirus CanineEndosomeBiophysicsPhospholipidBiologyAntidepressive Agents Tricyclicchemistry.chemical_compoundDogsStructural BiologyDesipraminemedicineAnimalsComputer SimulationMolecular BiologyCells CulturedMolecular StructureVesicleCell MembraneDesipramineCell BiologyRaftDisease Models AnimalMembraneCholesterolchemistryBiochemistryBiophysicslipids (amino acids peptides and proteins)Sphingomyelinhuman activitiesIntracellularmedicine.drug
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Estimation of Passenger Car Equivalents for single-lane roundabouts using a microsimulation-based procedure

2017

Calibration of microscopic traffic simulation models for single-lane roundabouts.Use of a meta-analytical estimation of critical and follow up headways.Use of a genetic algorithm-based procedure.Calculation of passenger car equivalents for single-lane roundabouts. Passenger car equivalents for heavy vehicles are required to carry out capacity calculations and perform operational analysis of any road entity (roadway segments or intersections). At single-lane roundabouts, the constraints to the vehicular trajectories imposed by the curvilinear geometric design and the driver's gap acceptance behaviour are expected to produce an impact of the heavy vehicles on the quality of traffic flow diffe…

Passenger car equivalent050210 logistics & transportationComputer science05 social sciencesGeneral EngineeringMicrosimulationTraffic simulation02 engineering and technologyTraffic flowAimsunAutomotive engineeringComputer Science ApplicationsGenetic algorithmSettore ING-INF/04 - AutomaticaArtificial IntelligenceCalibration0502 economics and businessPath (graph theory)Roundabout0202 electrical engineering electronic engineering information engineeringSettore ICAR/04 - Strade Ferrovie Ed AeroportiSingle-lane roundabout020201 artificial intelligence & image processingPassenger car equivalentMicroscopic traffic simulation modelExpert Systems with Applications
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Modelling the spatial and temporal constrains of the GABAergic influence on neuronal excitability

2021

GABA (γ-amino butyric acid) is an inhibitory neurotransmitter in the adult brain that can mediate depolarizing responses during development or after neuropathological insults. Under which conditions GABAergic membrane depolarizations are sufficient to impose excitatory effects is hard to predict, as shunting inhibition and GABAergic effects on spatiotemporal filtering of excitatory inputs must be considered. To evaluate at which reversal potential a net excitatory effect was imposed by GABA (EGABAThr), we performed a detailed in-silico study using simple neuronal topologies and distinct spatiotemporal relations between GABAergic and glutamatergic inputs. These simulations revealed for GABAe…

Patch-Clamp TechniquesAction potentialPhysiologyAction PotentialsSynaptic TransmissionNervous SystemBiochemistryMiceNerve FibersAnimal CellsMedicine and Health SciencesGABAergic NeuronsBiology (General)gamma-Aminobutyric AcidNeuronsMembrane potentialEcologyChemistryPyramidal CellsDepolarizationNeurochemistryNeurotransmittersCA3 Region HippocampalElectrophysiologyReceptors GlutamateComputational Theory and MathematicsModeling and SimulationExcitatory postsynaptic potentialGABAergicAnatomyCellular TypesShunting inhibitionResearch Articlemedicine.drugQH301-705.5Models NeurologicalNeurophysiologyAMPA receptorMembrane Potentialgamma-Aminobutyric acidCellular and Molecular NeuroscienceGlutamatergicSpatio-Temporal AnalysisGeneticsmedicineAnimalsComputer SimulationReceptors AMPAReversal potentialMolecular BiologyEcology Evolution Behavior and SystematicsComputational BiologyBiology and Life SciencesNeural InhibitionDendritesCell BiologyNeuronal DendritesAxonsMice Inbred C57BLAnimals Newbornnervous systemCellular NeuroscienceSynapsesDepolarizationNeuroscienceNeurosciencePLOS Computational Biology
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Transportation-cost inequality on path spaces with uniform distance

2008

Abstract Let M be a complete Riemannian manifold and μ the distribution of the diffusion process generated by 1 2 ( Δ + Z ) where Z is a C 1 -vector field. When Ric − ∇ Z is bounded below and Z has, for instance, linear growth, the transportation-cost inequality with respect to the uniform distance is established for μ on the path space over M . A simple example is given to show the optimality of the condition.

Path (topology)Statistics and ProbabilityTransportation-cost inequalityPath spaceApplied MathematicsMathematical analysisRiemannian manifoldManifoldUniform distanceQuasi-invariant flowDistribution functionModeling and SimulationBounded functionModelling and SimulationVector fieldMathematics::Differential GeometryInvariant (mathematics)Damped gradientDistribution (differential geometry)MathematicsStochastic Processes and their Applications
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