Search results for "Gaussia"

showing 10 items of 653 documents

Quality of wind speed fitting distributions for the urban area of Palermo, Italy

2011

Abstract This study investigates the wind speed characteristics recorded in the urban area of Palermo, in the south of Italy, by a monitoring network composed by four weather stations. This article has two main objectives: the first one, to describe with clarity and simplicity the numerical procedures adopted to perform a preliminary statistical analysis of wind speed data, providing at the same time, the necessary mathematical tools useful to perform this analysis also without special software. The second objective is to verify if there are more suitable probability distributions able to better represent the original data respect the traditional ones. After a preliminary statistical analys…

Urban wind speed distributionSettore ING-IND/11 - Fisica Tecnica AmbientaleBurr distributionRenewable Energy Sustainability and the EnvironmentRayleigh distributionProbability density functionWind speedBurr distributionInverse Gaussian distributionsymbols.namesakeStatisticsMaximum likelihood methodsymbolsGamma distributionProbability distributionWeibull distributionMathematicsWeibull distributionRenewable Energy
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LQG Control Design for Balancing an Inverted Pendulum Mobile Robot

2011

Author's version of an article published in the journal: Intelligent Control and Automation. Also available from the publisher at: http://dx.doi.org/10.4236/ica.2011.22019 The objective of this paper is to design linear quadratic controllers for a system with an inverted pendulum on a mobile robot. To this goal, it has to be determined which control strategy delivers better performance with respect to pendulum’s angle and the robot’s position. The inverted pendulum represents a challenging control problem, since it continually moves toward an uncontrolled state. Simulation study has been done in MATLAB Simulink environment shows that both LQR and LQG are capable to control this system succe…

VDP::Mathematics and natural science: 400::Mathematics: 410::Applied mathematics: 413Engineeringbusiness.industryVDP::Technology: 500::Mechanical engineering: 570Control (management)PendulumControl engineeringMobile robotLinear quadraticLinear-quadratic-Gaussian controlInverted pendulumComputer Science::RoboticsComputer Science::Systems and ControlPosition (vector)Control theoryRobotbusinessLQG control inverted pendulum mobile robotIntelligent Control and Automation
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Pressure Dependence of the Band Gaps and Charge Densities in Si

1994

The empirical local and nonlocal pseudopotentials of Si which can describe the electronic energy structure over a wide energy range of more than 20 eV from the bottom of the valence band is determined for different pressures. The nonlocality of the potential is described by the Gaussian model. The predictions for the linear and quadratic pressure coefficients are consistent with the experiment. The valence charge densities of Si under high pressure are studied. The forbidden X-ray factor F(222) is very stable under pressure and changes by less than 3% under volume changes of the order of 5%.

Valence (chemistry)Condensed matter physicsBand gapChemistryPressure dependenceCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsQuantum nonlocalitysymbols.namesakeQuadratic equationHigh pressuresymbolsValence bandAtomic physicsGaussian network modelphysica status solidi (b)
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Nonstationary response envelope probability densities of nonlinear oscillators

2006

The nonstationary random response of a class of lightly damped nonlinear oscillators subjected to Gaussian white noise is considered. An approximate analytical method for determining the response envelope statistics is presented. Within the framework of stochastic averaging, the procedure relies on the Markovian modeling of the response envelope process through the definition of an equivalent linear system with response-dependent parameters. An approximate solution of the associated Fokker-Planck equation is derived by resorting to a Galerkin scheme. Specifically, the nonstationary probability density function of the response envelope is expressed as the sum of a time-dependent Rayleigh dis…

Van der Pol oscillatorRayleigh distributionMechanical EngineeringLinear systemComputational MechanicsBasis functionProbability density functionWhite noiseCondensed Matter Physicssymbols.namesakeMechanics of MaterialsGaussian noisesymbolsApplied mathematicsMechanics of MaterialEnvelope (waves)Mathematical physicsMathematics
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Quantifying Fundamental Vegetation Traits over Europe Using the Sentinel-3 OLCI Catalogue in Google Earth Engine

2022

Thanks to the emergence of cloud-computing platforms and the ability of machine learning methods to solve prediction problems efficiently, this work presents a workflow to automate spatiotemporal mapping of essential vegetation traits from Sentinel-3 (S3) imagery. The traits included leaf chlorophyll content (LCC), leaf area index (LAI), fraction of absorbed photosynthetically active radiation (FAPAR), and fractional vegetation cover (FVC), being fundamental for assessing photosynthetic activity on Earth. The workflow involved Gaussian process regression (GPR) algorithms trained on top-of-atmosphere (TOA) radiance simulations generated by the coupled canopy radiative transfer model (RTM) SC…

Vegetation traitsTime seriesvegetation traits; Sentinel-3; TOA radiance; OLCI; Gaussian process regression; machine learning; hybrid method; time series; Google Earth EngineTOA radianceMachine learningHybrid methodGeneral Earth and Planetary SciencesMatemática AplicadaSentinel-3OLCIGoogle Earth EngineGaussian process regressionRemote Sensing
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A Probabilistic Classification Procedure Based on Response Time Analysis Towards a Quick Pre-Diagnosis of Student's Attention Deficit

2019

[EN] A classification methodology based on an experimental study is proposed towards a fast pre-diagnosis of attention deficit. Our sample consisted of school-aged children between 8 and 12 years from Valencia, Spain. The study was based on the response time (RT) to visual stimuli in computerized tasks. The process of answering consecutive questions usually follows an ex-Gaussian distribution of the RTs. Specifically, we seek to propose a simple automatic classification scheme of children based on the most recent evidence of the relationship between RTs and ADHD. Specifically, the prevalence percentage and reported evidence for RTs in relation to ADHD or to attention deficit symptoms were t…

Visual perceptionRelation (database)Process (engineering)General Mathematicsattention deficit hyperactivity disorder (ADHD) reaction time ex-Gaussian analysis.Sample (statistics)behavioral disciplines and activities050105 experimental psychology03 medical and health sciences0302 clinical medicineComputer Science (miscellaneous)medicineSelection (linguistics)0501 psychology and cognitive sciencesOverdiagnosisEngineering (miscellaneous)Reaction timeProbabilistic classificationlcsh:MathematicsEx-Gaussian analysis05 social sciencesCognitive disorderAttention deficit hyperactivity disorder (ADHD)medicine.diseaselcsh:QA1-939PsychologyMATEMATICA APLICADA030217 neurology & neurosurgeryCognitive psychology
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Diffuse soil CO2 degassing from Linosa island

2014

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Volcano monitoringLineamentGeochemistrysoil degassingfluid geochemistryCO2lcsh:QC851-999Instruments and techniques; Soil degassing; Volcano monitoring; GeophysicsSequential Gaussian simulationSoil co2 fluxFlux (metallurgy)Soil degassingGeomorphologygeographygeography.geographical_feature_categoryRiftlcsh:QC801-809Instruments and techniquesSettore GEO/08 - Geochimica E VulcanologiaTectonicslcsh:Geophysics. Cosmic physicsGeophysicsVolcanoLinosaSoil CO_2 fluxlcsh:Meteorology. ClimatologyGeologyChannel (geography)
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Structure of longitudinal chromomagnetic fields in high energy collisions

2014

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial fields correspond to a color field condensate exhibiting domain-like structure over distance scales of order the saturation scale. At later times universal scaling emerges at large distances for all ensembles, with a nontrivial critical exponent. Finally, we compare the results for the Wilson loop to the two-point correlator of magnetic fields.

We compute expectation values of spatial Wilson loops in the forward light cone of high-energy collisions. We consider ensembles of gauge field configurations generated from a classical Gaussian effective action as well as solutions of high-energy renormalization group evolution with fixed and running coupling. The initial like structure over distance scales of oder the saturation scale. At later times universal scaling emerges at large distances for all ensembles with a nontrivial critical exponent. Finally we compare the resulats for the Wilson loop to the two-point correlator of magnetic fields. (C) 2014 The Authors. Published by Elsevier BV This is an open access article under the CC BY licenseNuclear and High Energy PhysicsWilson loopLARGE NUCLEINuclear TheoryField (physics)FOS: Physical sciences114 Physical sciences01 natural sciencesColor-glass condensateRENORMALIZATION-GROUPNuclear Theory (nucl-th)GLUON DISTRIBUTION-FUNCTIONSHigh Energy Physics - Phenomenology (hep-ph)Light cone0103 physical sciencesSCATTERINGGauge theory010306 general physicsSMALL-XEffective actionPhysicsCORRELATORSta114010308 nuclear & particles physicsCOLOR GLASS CONDENSATERenormalization groupEVOLUTIONJIMWLK EQUATIONHigh Energy Physics - PhenomenologySATURATIONQuantum electrodynamicsCritical exponentPhysics Letters B
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Gaussian quadrature rule for arbitrary weight function and interval

2005

Abstract A program for calculating abscissas and weights of Gaussian quadrature rules for arbitrary weight functions and intervals is reported. The program is written in Mathematica. The only requirement is that the moments of the weight function can be evaluated analytically in Mathematica. The result is a FORTRAN subroutine ready to be utilized for quadrature. Program summary Title of program: AWGQ Catalogue identifier:ADVB Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVB Program obtained from: CPC Program Library, Queens University, Belfast, N. Ireland Computer for which the program is designed and others on which it has been tested: Computers: Pentium IV 1.7 GHz processor Ins…

Weight functionComputer scienceFortranMathematicsofComputing_NUMERICALANALYSISGeneral Physics and AstronomyGauss–Kronrod quadrature formulaTanh-sinh quadratureQuadrature (mathematics)symbols.namesakeHardware and ArchitecturesymbolsGaussian quadratureAlgorithmcomputerClenshaw–Curtis quadratureTest datacomputer.programming_languageComputer Physics Communications
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Modified Gaussian models applied to the description and deconvolution of peaks in chiral liquid chromatography.

2020

Abstract The description of the profiles of chromatographic peaks has been studied extensively, with a large number of proposed mathematical functions. Among them, the accuracy achieved with modified Gaussian models that describe the deviation of an ideal Gaussian peak as a change in the peak variance or standard deviation over time, has been highlighted. These models are, in fact, a family of functions of different complexity with great flexibility to adjust chromatographic peaks over a wide range of asymmetries and shapes. However, an uncontrolled behaviour of the signal may occur outside the region being fitted, forcing the use of different strategies to overcome this problem. In this wo…

Work (thermodynamics)ChromatographyChemistryGaussian010401 analytical chemistryOrganic ChemistryNormal DistributionOrder (ring theory)StereoisomerismGeneral MedicineModels Theoretical010402 general chemistry01 natural sciencesBiochemistryStandard deviation0104 chemical sciencesAnalytical ChemistryExponential functionsymbols.namesakesymbolsRange (statistics)Limit (mathematics)DeconvolutionStatistical physicsChromatography LiquidJournal of chromatography. A
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