Search results for "Stochastic systems"

showing 3 items of 13 documents

Dynamical Ising-like model for the two-step spin-crossover systems

2003

In order to reproduce the two-step relaxation observed experimentally in spin-crossover systems, we investigate analytically the static and the dynamic properties of a two-sublattice Ising-like Hamiltonian. The formalism is based on a stochastic master equation approach. It is solved in the mean-field approximation, and yields two coupled differential equations that correspond to the HS fractions of the sublattices A and B. Virginie.Niel@uv.es ; Jose.A.Real@uv.es

PhysicsDifferential equationsIsing model ; Magnetic transitions ; Magnetic relaxation ; Master equation ; Stochastic systems ; Differential equations ; Spin HamiltoniansMagnetic transitionsSpin HamiltoniansStochastic systemsDifferential equationTwo stepUNESCO::FÍSICAGeneral Physics and AstronomyCoupled differential equationssymbols.namesakeFormalism (philosophy of mathematics)Spin crossover:FÍSICA [UNESCO]Master equationIsing modelsymbolsIsing modelStatistical physicsMaster equationHamiltonian (quantum mechanics)Magnetic relaxation

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Resonance phenomena in a nonlinear neuronal circuit

2015

International audience; We characterizes a nonlinear circuit driven by a bichromatic excitation,that is the sum of two sinusoidal waves with different frequencies f1 and f2 suchthat f2 > f1. Our experiments are confirmed by a numerical analysis of the systemresponse obtained by solving numerically the differential equations which rule thecircuit voltages. Especially, we highlight that the response of the system at the lowfrequency can be optimized by the amplitude of the high frequency. By revisiting thiswell known vibrational resonance effect in the whole amplitude frequency parametricplane, we show experimentally and numerically that a much better resonance can beachieved when the two fre…

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Stability of stochastic nonlinear systems with state-dependent switching

2013

In this paper, the problem of stability on stochastic systems with state-dependent switching is investigated. To analyze properties of the switched system by means of Itô’s formula and Dynkin’s formula, it is critical to show switching instants being stopping times. When the given active-region set can be replaced by its interior, the local solution of the switched system is constructed by defining a series of stopping times as switching instants, and the criteria on global existence and stability of solution are presented by Lyapunov approach. For the case where the active-region set can not be replaced by its interior, the switched systems do not necessarily have solutions, thereby quasi-…

stochastic systemsStability (learning theory)Mathematical proofnonlinear control systemsSet (abstract data type)State-dependent switching; Stochastic systems; Switched systems; Control and Systems Engineering; Computer Science Applications1707 Computer Vision and Pattern Recognition; Electrical and Electronic EngineeringExponential stabilityControl theoryElectrical and Electronic EngineeringSwitched systemsMathematicsLyapunov methodsStochastic systemsSeries (mathematics)Stochastic processApplied MathematicsComputer Science Applications1707 Computer Vision and Pattern Recognitionstate-dependent switchingstabilityComputer Science ApplicationsNonlinear systemControl and Systems EngineeringState dependentswitched systemscontrol system synthesisState-dependent switching

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