Search results for "parametric"

showing 10 items of 980 documents

Enhanced chain dynamics in loop-sorting-systems by means of layout optimization and a kinematic model of the polygon action

2012

Published version of an article in the journal: Structural and Multidisciplinary Optimization. Also available from the publisher at: http://dx.doi.org/10.1007/s00158-011-0743-7 Poor dynamics owing to polygon action is a known concern in mechanical applications of closed articulated chains. In this paper a kinematic model of the polygon action in large chains of loop-sorting-systems is proposed. Through optimization techniques the chain dynamics is improved by minimizing the polygon action using a parametric model of the track layout as design variables. Three formulations of the kinematic polygon action are tested on an average sized planer tracks layout to find a superior model. Verificati…

polygon actionLoop (graph theory)Mathematical optimizationControl and OptimizationComputer scienceengineeringVDP::Technology: 500::Mechanical engineering: 570SortingKinematicsloop-sorting-systemsComputer Graphics and Computer-Aided DesignAction (physics)Computer Science Applicationsmulti-body dynamicsChain (algebraic topology)Control and Systems EngineeringParametric modelPolygonEngineering design processAlgorithmoptimizationSoftware
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Acoustic, neural, and perceptual correlates of polyphonic timbre

2012

polyphonic timbremonophonic timbresointivärifMRInon-parametric statistical significance estimationhavaitseminenmusiikkipsykologiakognitiiviset prosessitfunctional magnetic resonance imagingacoustic featureshomofoniakorrelaatioaivokuoritoiminnallinen magneettikuvausperceptual dimensionstunteetakustiikkaaivotutkimuspolyfoniaaivot
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A generalized methodology for distribution systems faults identification, location and characterization

2005

Service continuity is of basic importance in the definition of the quality of the electrical energy, for this reason, the research in the field of faults diagnostic for distribution systems is spreading ever more. In this paper, a new methodology for diagnostic management of automated distribution systems is presented. The technique is based on the solution of a circuital model of the electrical system resulting from the composition of distributed parameters quadripoles. The solution gives as a result the identification of the type of fault, of its characteristic parameters and location. The paper shows an application to line to line grounded and ungrounded faults in which also its precisio…

protective relaysEngineeringFailure analysisbusiness.industryElectric potential energyIT service continuityPetri netsDiagnostic systemReliability engineeringDistribution systemElectric power systemRobustness (computer science)Distribution systemManagement systemFaults diagnosyManagement systembusinessDiagnostic systemParametric statistics
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Improving the Downwind Sail Design Process by Means of a Novel FSI Approach

2021

The process of designing a sail can be a challenging task because of the difficulties in predicting the real aerodynamic performance. This is especially true in the case of downwind sails, where the evaluation of the real shapes and aerodynamic forces can be very complex because of turbulent and detached flows and the high-deformable behavior of structures. Of course, numerical methods are very useful and reliable tools to investigate sail performances, and their use, also as a result of the exponential growth of computational resources at a very low cost, is spreading more and more, even in not highly competitive fields. This paper presents a new methodology to support sail designers in ev…

sail loadsComputer sciencefinite element methodNaval architecture. Shipbuilding. Marine engineeringVM1-989020101 civil engineeringOcean Engineering02 engineering and technologycomputational fluid dynamicsGC1-1581Computational fluid dynamicsOceanography01 natural sciences010305 fluids & plasmas0201 civil engineeringcomputational fluid dynamic0103 physical sciencesFSISettore ING-IND/15 - Disegno E Metodi Dell'Ingegneria IndustrialeWater Science and TechnologyCivil and Structural EngineeringParametric statisticsbusiness.industryNumerical analysisProcess (computing)Aerodynamicssail designFinite element methodgennakerAerodynamic forceDesign processbusinessMarine engineeringJournal of Marine Science and Engineering
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The pblm package: semiparametric regression for bivariate categorical responses in R

2014

We present an R package to fit semiparametric regression models for two categorical responses. It works for both nominal and ordered responses and several types of logits can be specified. Proportional, non-proportional and partial proportional odds models can be fitted, with marginal and association parameters estimated in a parametric or semiparametric way, via penalized maximum likelihood estimation. An application to show the potential of the package is carried out on a data set of Italian university students.

semiparametrically structured ordered modelpartial proportional-odds modelbivariate additive Dale modelstudents' performance
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Modeling of the Shear Connection Capacity of Hybrid Steel Trussed Composite Beams

2019

Hybrid Steel Trussed Composite Beams represent a technical solution in use in numerous countries since many years. They are able to join the advantages of prefabrication with those of cast in place structures: they are easy to manufacture, fast to realize, monolithic and with no need of formwork. The behavior of these beams has been recently topic of discussion in the scientific community because the knowledge both related to the reinforced concrete structures and that of composite constructions cannot be straightforwardly extended to this typology, which is intermediate between one and another technology. This paper provides a contribution towards a better understanding of the mechanism of…

shear capacityComputer sciencebusiness.industryComposite numberhybrid steel trussed composite beamsStructural engineeringhybrid steel trussed composite beams; push-out tests; FE modelling; shear capacitypush-out testFE modellingFE modelling; Hybrid steel trussed composite beams; Push-out tests; Shear capacityConnection (mathematics)PrefabricationShear (sheet metal)Settore ICAR/09 - Tecnica Delle Costruzionihybrid steel trussed composite beamSimple (abstract algebra)push-out testsFormworkbusinessBeam (structure)Parametric statistics
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Singular (p, q)-equations with superlinear reaction and concave boundary condition

2020

We consider a parametric nonlinear elliptic problem driven by the sum of a p-Laplacian and of a q-Laplacian (a (Formula presented.) -equation) with a singular and (Formula presented.) -superlinear reaction and a Robin boundary condition with (Formula presented.) -sublinear boundary term (Formula presented.). So, the problem has the combined effects of singular, concave and convex terms. We look for positive solutions and prove a bifurcation-type theorem describing the changes in the set of positive solutions as the parameter varies.

singular termConcave and convex nonlinearitiesnonlinear maximum principleApplied Mathematics010102 general mathematicsMathematical analysisSingular termBoundary (topology)Mathematics::Spectral Theory01 natural sciences010101 applied mathematicscomparison principlesNonlinear systemSettore MAT/05 - Analisi Matematicanonlinear regularity theoryBoundary value problem0101 mathematicstruncation (pq)-LaplacianAnalysisParametric statisticsMathematicsApplicable Analysis
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Soundscape design through evolutionary engines

2008

Abstract Two implementations of an Evolutionary Sound Synthesis method using the Interaural Time Difference (ITD) and psychoacoustic descriptors are presented here as a way to develop criteria for fitness evaluation. We also explore a relationship between adaptive sound evolution and three soundscape characteristics: keysounds, key-signals and sound-marks. Sonic Localization Field is defined using a sound attenuation factor and ITD azimuth angle, respectively (Ii, Li). These pairs are used to build Spatial Sound Genotypes (SSG) and they are extracted from a waveform population set. An explanation on how our model was initially written in MATLAB is followed by a recent Pure Data (Pd) impleme…

sonic spatializationeducation.field_of_studySoundscapesound synthesisGeneral Computer Scienceartificial evolutionComputer scienceSpeech recognitionacoustic descriptorsPopulationEvolutionary algorithmInteraural time differencegenetic algorithmsPure DataPsychoacousticseducationcomputerAcoustic attenuationParametric statisticscomputer.programming_languageComputer Science(all)
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Joint second-order parameter estimation for spatio-temporal log-Gaussian Cox processes

2018

We propose a new fitting method to estimate the set of second-order parameters for the class of homogeneous spatio-temporal log-Gaussian Cox point processes. With simulations, we show that the proposed minimum contrast procedure, based on the spatio-temporal pair correlation function, provides reliable estimates and we compare the results with the current available methods. Moreover, the proposed method can be used in the case of both separable and non-separable parametric specifications of the correlation function of the underlying Gaussian Random Field. We describe earthquake sequences comparing several Cox model specifications.

spatio-temporal pair correlation functionEnvironmental EngineeringGaussianminimum contrast methodnon-separable covariance function010502 geochemistry & geophysics01 natural sciencesPoint processGaussian random fieldSet (abstract data type)010104 statistics & probabilitysymbols.namesakeCorrelation functionEnvironmental Chemistry0101 mathematicsSafety Risk Reliability and Qualityearthquakes0105 earth and related environmental sciencesGeneral Environmental ScienceWater Science and TechnologyParametric statisticsMathematicslog-Gaussian Cox processesEstimation theoryContrast (statistics)symbolsEarthquakes Log-Gaussian Cox processes Minimum contrast method Non-separable covariance function Spatio-temporal pair correlation functionSettore SECS-S/01 - StatisticaAlgorithm
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SNP and SML estimation of univariate and bivariate binary–choice models

2008

We discuss the semi-nonparametric approach of Gallant and Nychka (1987, Econometrica 55: 363–390), the semiparametric maximum likelihood approach of Klein and Spady (1993, Econometrica 61: 387–421), and a set of new Stata commands for semiparametric estimation of three binary-choice models. The first is a univariate model, while the second and the third are bivariate models without and with sample selection, respectively. The proposed estimators are root-n consistent and asymptotically normal for the model parameters of interest under weak assumptions on the distribution of the underlying error terms. Our Monte Carlo simulations suggest that the efficiency losses of the semi-nonparametric a…

st0000 snp snp2 snp2s sml sml2s binary-choice models seminonparametric approach SNP estimation semiparametric maximum likelihood SML estimation Monte Carlo simulationSettore SECS-P/05 - EconometriaSettore SECS-P/01 - Economia Politica
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