Search results for "C [POLY I]"

showing 10 items of 30703 documents

Hysteretic Systems Subjected to Delta Correlated Input

1994

The paper deals with the evaluation of the probabilistic response of a single degree of freedom elastic-perfectly plastic system subjected to a delta correlated input process. The probabilistic characterisation of the response is here obtained by considering the accumulated plastic deformations as a compound homogeneous Poisson process independent of the external input. In this case the former can be considered as an external noise acting on the linear system. A closed form solution is also obtained and the analytic expression is compared with the customary Monte-Carlo method.

symbols.namesakeAnalytical expressionsMathematical analysisLinear systemsymbolsProbabilistic logicProcess (computing)Poisson processExternal noiseClosed-form expressionSingle degree of freedomMathematics
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Assessing Transfer Entropy in cardiovascular and respiratory time series: A VARFI approach

2021

In the study of complex biomedical systems represented by multivariate stochastic processes, such as the cardiovascular and respiratory systems, an issue of great relevance is the description of the system dynamics spanning multiple temporal scales. Recently, the quantification of multiscale complexity based on linear parametric models, incorporating autoregressive coefficients and fractional integration, encompassing short term dynamics and long-range correlations, was extended to multivariate time series. Within this Vector AutoRegressive Fractionally Integrated (VARFI) framework formalized for Gaussian processes, in this work we propose to estimate the Transfer Entropy, or equivalently G…

symbols.namesakeAutoregressive modelDynamical systems theoryGranger causalityComputer scienceStochastic processPhysics::Medical PhysicsParametric modelsymbolsTransfer entropyStatistical physicsGaussian processSystem dynamicsProceedings of Entropy 2021: The Scientific Tool of the 21st Century
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Rotational collisional line broadening at high temperatures in the N2 fundamental Q-branch studied with stimulated Raman spectroscopy

1986

Self broadened N 2 Q-branch spectra are measured by high resolution stimulated Raman spectroscopy in the pressure region 0.25-1.9 atm. and in the temperature range 295-1310 K. Non additivity of the Q(J) components due to line overlap arising in the highest pressure range explored is carefully taken into account. Excellent fit of the whole spectra is thus obtained for each pressure with linearly density-dependent line widths. Semi-classical calculations of the line-broadening coefficients lead to consistent values with all the measured ones. These calculations are extended to higher J values and to higher temperatures (up to 2500 K). At last, a simple phenomenological model based on a polyno…

symbols.namesakeChemistryPhenomenological modelsymbolsMineralogyRotational transitionAtomic physicsAtmospheric temperature rangeSpectroscopyRaman scatteringSpectral lineRotational energyLine (formation)Journal de Physique
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Spontaneous Raman Scattering Spectrum of Gaseous IrF6 in the Ground Electronic State

1996

symbols.namesakeChemistrySpectrum (functional analysis)symbolsGeneral Materials ScienceState (functional analysis)Atomic physicsRaman spectroscopySpectroscopyRaman scatteringJournal of Raman Spectroscopy
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Collisional Relaxation Processes Studied by Coherent Raman Spectroscopy for Major Species Present in Combustions

1992

The effects of collisional relaxation processes on the Q-branch profile of major species present in combustions have been studied by high resolution stimulated Raman spectroscopy. Particular interest has focused on the following collisional systems: N2-N2, O2-O2, CO2-CO2, O2-N2, N2-CO2 and N2-H2O. For each colliding pair, starting from accurate determinations of line broadening coefficients over a wide temperature range, state-to-state rates for rotational energy transfers have been deduced by using various fitting laws. Among these rate laws, special attention has been paid to the temperature dependence of the energy corrected scaling (ECS) law combined with a hybrid exponential-power law …

symbols.namesakeChemistrysymbolsRelaxation (physics)Rate equationAtomic physicsSpectroscopyRaman spectroscopyMotional narrowingScalingSpectral line shapeRotational energy
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Impulsive excitation of high vibrational states in I2–Xe complex on the electronic ground state

2010

Abstract High vibrational states, up to ν  = 22, are excited and investigated on the ground electronic state of a 1:1 I 2 –Xe complex isolated in solid Kr using femtosecond CARS technique and spontaneous resonant Raman measurements. The results show that this system is a promising candidate for investigations of coherent control of bimolecular reactions by using vibrational wavepackets on the ground electronic state.

symbols.namesakeCoherent controlChemistryExcited stateFemtosecondsymbolsGeneral Physics and AstronomyCoherent anti-Stokes Raman spectroscopyPhysical and Theoretical ChemistryAtomic physicsGround stateRaman spectroscopyExcitationChemical Physics Letters
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On the spectrum of semi-classical Witten-Laplacians and Schrödinger operators in large dimension

2005

We investigate the low-lying spectrum of Witten–Laplacians on forms of arbitrary degree in the semi-classical limit and uniformly in the space dimension. We show that under suitable assumptions implying that the phase function has a unique local minimum one obtains a number of clusters of discrete eigenvalues at the bottom of the spectrum. Moreover, we are able to count the number of eigenvalues in each cluster. We apply our results to certain sequences of Schrodinger operators having strictly convex potentials and show that some well-known results of semi-classical analysis hold also uniformly in the dimension.

symbols.namesakeDimension (vector space)Degree (graph theory)Mathematical analysisSpectrum (functional analysis)Thermodynamic limitsymbolsLimit (mathematics)Convex functionAnalysisEigenvalues and eigenvectorsSchrödinger's catMathematicsJournal of Functional Analysis
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Excitation Energy-Transfer in the LH2 Antenna of Photosynthetic Purple Bacteria via Excitonic B800 and B850 States

2000

A newly developed CIEM method that uses a combination of semi-empirical or ab-initio configuration interaction methods and exciton theory to predict electronic energies, eigenstates, absorption and CD spectra of aggregated chromophoric systems with environmental interactions included is extended and used for estimation of excitation energy transfer rates. Excitonic energy levels of the two ring systems the B800 and the B850 of the light harvesting antenna LH2 of Rhodopseudomonas acidophila and the corresponding absorption spectrum were calculated by assuming inter-ring interactions to be zero. Excitation energy transfer rates were calculated by using the Fermi Golden rule with the dipole - …

symbols.namesakeDipoleAbsorption spectroscopyChemistryExcitonsymbolsFermi's golden ruleGeneral ChemistryAtomic physicsConfiguration interactionHamiltonian (quantum mechanics)ExcitationSpectral lineJournal of the Chinese Chemical Society
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Thermodynamics: Classical Framework

2016

This chapter starts with a summary of the thermodynamic potentials and the relationships between them which are obtained from Legendre transformation. This is followed by an excursion to some important global properties of materials such as specific heat, expansion coefficients and others. The thermodynamic relations provide the basis for a discussion of continuous changes of state which are illustrated by the Joule-Thomson effect and the Van der Waals gas. These are models which are more realistic than the ideal gas. The discussion of Carnot cycles leads to and illustrates the second and third laws of thermodynamics. The chapter closes with a discussion of entropy as a concave function of …

symbols.namesakeEntropy (classical thermodynamics)Fundamental thermodynamic relationOn the Equilibrium of Heterogeneous SubstancessymbolsNon-equilibrium thermodynamicsStatistical physicsCarnot cycleThermodynamic systemLaws of thermodynamicsThermodynamic potentialMathematics
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A Self-Contained Biometric Sensor for Ubiquitous Authentication

2007

This paper describes a real-life behavior framework in simulation game based on Probabilistic State Machine (PSM) with Gaussian random distribution. According to the dynamic environment information, NPC can generate behavior planning autonomously associated with defined FSM. After planning process, we illuminate Gaussian probabilistic function for real-life action simulation in time and spatial domains. The expected value of distribution is estimated during behavior planning process and variance is determined by NPC personality in order to realize real life behavior simulation. We experiment the framework and Gaussian PSM on a restaurant simulation game. Furthermore we give some suggestions…

symbols.namesakeFinite-state machineTheoretical computer scienceComputer scienceGaussianAutonomous agentProbabilistic logicsymbolsVariance (accounting)Function (mathematics)Expected valueVirtual reality
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