Search results for " statistica"

showing 10 items of 2672 documents

Characterization of a new natural fiber from Arundo donax L. as potential reinforcement of polymer composites.

2013

Abstract The aim of this paper is to study the possibility of using of Arundo donax L. fibers as reinforcement in polymer composites. The fibers are extracted from the outer part of the stem of the plant, which widely grows in Mediterranean area and is diffused all around the world. To use these lignocellulosic fibers as reinforcement in polymer composites, it is necessary to investigate their microstructure, chemical composition and mechanical properties. Therefore, the morphology of A. donax L. fibers was investigated through electron microscopy, the thermal behavior through thermogravimetric analysis and the real density through a helium pycnometer. The chemical composition of the natura…

Dietary FiberThermogravimetric analysisMaterials sciencePolymers and PlasticsPolymersPoaceaeLigninchemistry.chemical_compoundPolysaccharidesTensile StrengthUltimate tensile strengthMaterials TestingSpectroscopy Fourier Transform InfraredMaterials ChemistryHemicelluloseCelluloseComposite materialCelluloseNatural fiberbiologyOrganic ChemistryTemperatureArundo donaxMicrostructurebiology.organism_classificationCharacterization (materials science)Arundo donax fiber Mechanical property Infrared spectroscopy Thermogravimetric analysis Scanning electron microscopy Statistical analysisSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialichemistryMicroscopy Electron ScanningCarbohydrate polymers
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ideal: an R/Bioconductor package for interactive differential expression analysis

2020

AbstractBackgroundRNA sequencing (RNA-seq) is an ever increasingly popular tool for transcriptome profiling. A key point to make the best use of the available data is to provide software tools that are easy to use but still provide flexibility and transparency in the adopted methods. Despite the availability of many packages focused on detecting differential expression, a method to streamline this type of bioinformatics analysis in a comprehensive, accessible, and reproducible way is lacking.ResultsWe developed the ideal software package, which serves as a web application for interactive and reproducible RNA-seq analysis, while producing a wealth of visualizations to facilitate data interpr…

Differential expression analysisComputer scienceShinyBioconductorInteractive data analysislcsh:Computer applications to medicine. Medical informaticsReproducible researchBioconductorDifferential expressionCode (cryptography)Transcriptome profilingHumansRNA-SeqTranscriptomicslcsh:QH301-705.5Flexibility (engineering)Ideal (set theory)Base Sequencebusiness.industryData visualizationGene Expression ProfilingRRNAReproducibility of ResultsTransparency (human–computer interaction)Gene Expression Regulationlcsh:Biology (General)Data Interpretation StatisticalWeb applicationlcsh:R858-859.7Software engineeringbusinessSoftwareBMC Bioinformatics
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Devil’s vortex-lenses

2009

In this paper we present a new kind of vortex lenses in which the radial phase distribution is characterized by the "devil's staircase" function. The focusing properties of these fractal DOEs coined Devil's vortex-lenses are analytically studied and the influence of the topological charge is investigated. It is shown that under monochromatic illumination a vortex devil's lens give rise a focal volume containing a delimited chain of vortices that are axially distributed according to the self-similarity of the lens.

DiffractionOptics and PhotonicsLightOptical TweezersAstrophysics::Cosmology and Extragalactic Astrophysicslaw.inventionFractalOpticslawCondensed Matter::SuperconductivityTopological quantum numberPhysicsModels Statisticalbusiness.industryEquipment DesignModels TheoreticalAtomic and Molecular Physics and OpticsVortexLens (optics)FractalsClassical mechanicsMonochromatic colorAxial symmetrybusinessOptical vortexAlgorithmsOptics Express
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Fast and robust phase-shift estimation in two-dimensional structured illumination microscopy.

2019

A method of determining unknown phase-shifts between elementary images in two-dimensional Structured Illumination Microscopy (2D-SIM) is presented. The proposed method is based on the comparison of the peak intensity of spectral components. These components correspond to the inherent structured illumination spectral content and the residual compo- nent that appears from wrongly estimated phase-shifts. The estimation of the phase-shifts is carried out by finding the absolute maximum of a function defined as the normalized peak intensity difference in the Fourier domain. This task is performed by an optimization method providing a fast estimation of the phase-shift. The algorithm stability an…

DiffractionStatistical NoisePhotonStructured illumination microscopy02 engineering and technologySignal-To-Noise RatioResidual01 natural sciencesPhase DeterminationMathematical and Statistical TechniquesFluorescence MicroscopyImage Processing Computer-AssistedFourier Anàlisi deMathematicsMicroscopyMultidisciplinaryFourier AnalysisPhysicsApplied MathematicsSimulation and ModelingStatisticsQRLight Microscopy021001 nanoscience & nanotechnologyGaussian NoiseMicroscòpiaFourier analysisPhysical SciencessymbolsCrystallographic TechniquesMedicine0210 nano-technologyAlgorithmDiffractionElementary ParticlesAlgorithmsResearch ArticleImaging TechniquesComputationScienceResearch and Analysis Methods010309 opticssymbols.namesakeRobustness (computer science)0103 physical sciencesParticle PhysicsPhotonsMicroscopy FluorescenceGaussian noiseWavesMathematicsImatges Processament Tècniques digitalsPLoS ONE
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Levy targeting and the principle of detailed balance

2011

We investigate confining mechanisms for Lévy flights under premises of the principle of detailed balance. In this case, the master equation of the jump-type process admits a transformation to the Lévy-Schrödinger semigroup dynamics akin to a mapping of the Fokker-Planck equation into the generalized diffusion equation. This sets a correspondence between above two stochastic dynamical systems, within which we address a (stochastic) targeting problem for an arbitrary stability index μ ε (0,2) of symmetric Lévy drivers. Namely, given a probability density function, specify the semigroup potential, and thence the jump-type dynamics for which this PDF is actually a long-time asymptotic (target) …

Diffusion equationDynamical systems theoryMovementNormal DistributionFOS: Physical sciencesDiffusionOscillometryMaster equationFOS: MathematicsApplied mathematicsCondensed Matter - Statistical MechanicsMathematical PhysicsMathematicsStochastic ProcessesModels StatisticalStatistical Mechanics (cond-mat.stat-mech)SemigroupStochastic processPhysicsProbability (math.PR)Mathematical analysisCauchy distributionDetailed balanceMathematical Physics (math-ph)Markov ChainsTransformation (function)ThermodynamicsAlgorithmsMathematics - Probability
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Generalized Wiener Process and Kolmogorov's Equation for Diffusion induced by Non-Gaussian Noise Source

2005

We show that the increments of generalized Wiener process, useful to describe non-Gaussian white noise sources, have the properties of infinitely divisible random processes. Using functional approach and the new correlation formula for non-Gaussian white noise we derive directly from Langevin equation, with such a random source, the Kolmogorov's equation for Markovian non-Gaussian process. From this equation we obtain the Fokker-Planck equation for nonlinear system driven by white Gaussian noise, the Kolmogorov-Feller equation for discontinuous Markovian processes, and the fractional Fokker-Planck equation for anomalous diffusion. The stationary probability distributions for some simple cas…

Diffusion equationStatistical Mechanics (cond-mat.stat-mech)General MathematicsMathematical analysisGeneral Physics and AstronomyFOS: Physical sciencesOrnstein–Uhlenbeck processCondensed Matter - Soft Condensed MatterGaussian random fieldLangevin equationsymbols.namesakeStochastic differential equationAdditive white Gaussian noiseGaussian noisesymbolsProcess and Kolmogorov'sSoft Condensed Matter (cond-mat.soft)Fokker–Planck equationCondensed Matter - Statistical MechanicsMathematics
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Dimensioni di benessere tra le famiglie italiane. Un’analisi sui dati EU-SILC 2005

2009

Il presente lavoro, utilizzando le informazioni dell’indagine EU-SILC (European Statistics on Income and Living Conditions) del 2005 su 22.032 famiglie italiane, si pone come obiettivo l’analisi e la misura del benessere multidimensionale. Nel paragrafo 2 sono riportate le ipotesi teoriche, mentre nel paragrafo 3 è riportata l’analisi dei risultati e alcune considerazioni conclusive.

Dimensioni del benessere logitSettore SECS-S/03 - Statistica Economica
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Path-wise versus kinetic modeling for equilibrating non-Langevin jump-type processes

2014

We discuss two independent methods of solution of a master equation whose biased jump transition rates account for long jumps of L\'{e}vy-stable type and nonetheless admit a Boltzmannian (thermal) equilibrium to arise in the large time asymptotics of a probability density function $\rho (x,t)$. Our main goal is to demonstrate a compatibility of a {\it direct} solution method (an explicit, albeit numerically assisted, integration of the master equation) with an {\it indirect} path-wise procedure, recently proposed in [Physica {\bf A 392}, 3485, (2013)] as a valid tool for a dynamical analysis of non-Langevin jump-type processes. The path-wise method heavily relies on an accumulation of large…

Direct solution methodStatistical Mechanics (cond-mat.stat-mech)PhysicsQC1-999cauchy driverGeneral Physics and AstronomyFOS: Physical sciencesmaster equationProbability density functionlévy processesKinetic energynon-langevin modellinggillespie’s algorithmLévy processboltzmann equilibriumThermalMaster equationJumpStatistical analysisStatistical physicsCondensed Matter - Statistical Mechanicspath-wise modellingMathematics
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Quasi Conjunction and Inclusion Relation in Probabilistic Default Reasoning

2011

We study the quasi conjunction and the Goodman & Nguyen inclusion relation for conditional events, in the setting of probabilistic default reasoning under coherence. We deepen two recent results given in (Gilio and Sanfilippo, 2010): the first result concerns p-entailment from a family F of conditional events to the quasi conjunction C(S) associated with each nonempty subset S of F; the second result, among other aspects, analyzes the equivalence between p-entailment from F and p-entailment from C(S), where S is some nonempty subset of F. We also characterize p-entailment by some alternative theorems. Finally, we deepen the connections between p-entailment and the Goodman & Nguyen inclusion…

Discrete mathematicsClass (set theory)goodman & nguyen inclusion relationSettore MAT/06 - Probabilita' E Statistica MatematicaSettore INF/01 - Informaticap-entailment.; quasi conjunction; goodman & nguyen inclusion relation; qand rule; coherence; probabilistic default reasoning; p-entailmentProbabilistic logicqand ruleprobabilistic default reasoningConsistency (knowledge bases)Coherence (philosophical gambling strategy)p-entailmentCoherence probabilistic default reasoning quasi conjunction Goodman & Nguyen inclusion relation QAND rule p-entailment.coherenceConjunction (grammar)Default reasoningquasi conjunctionGreatest elementAlgorithmEquivalence (measure theory)Mathematics
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Centering and Compound Conditionals under Coherence

2016

There is wide support in logic , philosophy , and psychology for the hypothesis that the probability of the indicative conditional of natural language, \(P(\textit{if } A \textit{ then } B)\), is the conditional probability of B given A, P(B|A). We identify a conditional which is such that \(P(\textit{if } A \textit{ then } B)= P(B|A)\) with de Finetti’s conditional event, B|A. An objection to making this identification in the past was that it appeared unclear how to form compounds and iterations of conditional events. In this paper, we illustrate how to overcome this objection with a probabilistic analysis, based on coherence, of these compounds and iterations. We interpret the compounds a…

Discrete mathematicsIndicative conditionalcenteringSettore MAT/06 - Probabilita' E Statistica Matematica05 social sciencesClassical logicConditional probabilityInference02 engineering and technologyCoherence (philosophical gambling strategy)p-entailmentn-conditional event050105 experimental psychologycoherenceLogical biconditionalp-validity0202 electrical engineering electronic engineering information engineeringbiconditional event020201 artificial intelligence & image processing0501 psychology and cognitive sciencesProbabilistic analysis of algorithmsArithmeticMathematicsEvent (probability theory)Conditional
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