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Kang-Kang Wang Lin Ju Ya-Jun Wang Sheng-Hong Li 《Chinese Journal of Physics (Taipei)》2018,56(1):96-107
In this paper, we focus on investigating the steady-state shift behaviors and the stochastic resonance phenomenon (SR) for a biological insect population system with a multiplicative periodic signal caused by the terms of the colored multiplicative and additive noises. Our research results imply that the multiplicative noise and the self-correlation of the additive noise can weaken the stability of the biological system and restrain the growth of the insect population, while the additive noise and the self-correlation time of the multiplicative noise can strengthen the stability of the insect system and facilitate the biological population to breed. As regards to the phenomenon of the SR evoked by a multiplicative periodic signal, noise terms and their correlation times, the computed results show that the additive noise intensity M and the self- correlation time τ1 of the multiplicative noise can both improve the SR effect. Inversely, the multiplicative noise intensity Q and the self-correlation time τ2 of the additive noise can suppress together the SR phenomenon. Whereas, it should be pointed out that in the SNR-Q and SNR-M plots, the two self-correlation times can both motivate a resonant peak, but not change the peak value of the SNR no matter how the two noise correlation times vary. 相似文献
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Yanfei Jin 《Physica A》2012,391(5):1928-1933
The resonance behaviors, such as coherence resonance and stochastic resonance, are studied in a delayed bistable system subject to correlated noises and a weak harmonic excitation. For weak noise intensities and small feedback gains, the analytic expressions of output spectrum and linear spectrum amplification are derived based on the theory proposed by Tsimring [14] [L.S. Tsimring, A. Pikovsky, Noise-induced dynamics in bistable systems with delay, Phys. Rev. Lett. 87 (2001) 250602]. The results show that the peak in the output spectrum at the frequency corresponding to the time delay attains the maximum for an intermediate amount of noise intensity and the coherence resonance appears. The correlation between noises can induce the suppression and the stochastic resonance in the curve of spectrum amplification, which is absent for the case of uncorrelated additive and multiplicative noises. Moreover, the system also exhibits the frequency stochastic resonance. 相似文献
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The coherent interaction of the electromagnetic radiation with an ensemble of polarizable, identical particles with two energy levels is investigated in the presence of external electromagnetic fields. The coupled non-linear equations of motion are solved in the stationary regime and in the limit of small coupling constants. It is shown that an external electromagnetic field may induce a macroscopic occupation of both the energy levels of the particles and the corresponding photon states, governed by a long-range order of the quantum phases of the internal motion (polarization) of the particles. A lasing effect is thereby obtained, controlled by the external field. Its main characteristics are estimated for typical atomic matter and atomic nuclei. For atomic matter the effect may be considerable (for usual external fields), while for atomic nuclei the effect is extremely small (practically insignificant), due to the great disparity in the coupling constants. In the absence of the external field, the solution, which is non-analytic in the coupling constant, corresponds to a second-order phase transition (super-radiance), which was previously investigated. 相似文献
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Based on the exponential monostable potential, we study an exponential monostable system with time-delayed feedback driven by weak periodic signals and additive Gaussian white noises. The small delay approximation is used to deduce the steady-state probability distribution and the effective potential function is derived. The system parameters l and b, time delay τ, feedback strength β can change the shapes of the potential function. The mean first-passage time (MFPT) is calculated, which plays an extremely important role in the research of particles escape. And the signal-to-noise ratio (SNR) of the system can be obtained by using the adiabatic approximation theory. The phenomenon of stochastic resonance is investigated under different system parameters and time-delayed feedback. The amplitude of SNR can be changed by adjusting the system parameters. When the feedback strength β is positive (or negative), the time delay τ can promote (or suppress) the stochastic resonance phenomenon. The SNR versus the noise intensity D presents the stochastic resonance phenomenon. In addition, the SNR increases non-monotonically with the increasing feedback strength β and the parameter b. Also, the analysis and numerical simulation results of SNR are in good agreement with the formula simulation. 相似文献
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An array of overdamped bistable oscillators with delay was studied numerically. Each site of the array is coupled directionally with the addition of white Gaussian noise. On the other hand, we compared the results with an array of coupled chain of experimental devices, also fed with Gaussian white noise. We observed for an optimal amount of noise and moderated coupling good transmission along the line without degradation. 相似文献
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We studied the motion of an underdamped Brownian particle in a periodic potential subject to a harmonic excitation and a colored noise. The average input energy per period and the phase lag are calculated to quantify the phenomenon of stochastic resonance (SR). The numerical results show that most of the out-of-phase trajectories make a transition to the in-phase state as the temperature increases. And the colored noise delays the transitions between these two dynamical states. The each curve of the average input energy per period and the phase lag versus the temperature exist a mono peak and SR appears in this system. Moreover, the optimal temperature where the SR occurs becomes larger and the region of SR grows wider as the correlation time of colored noise increases. 相似文献
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The phenomenon of stochastic resonance is investigated in an asymmetric bistable system with coloured noises.The approximate Fokker-Planck equation is derived based on the Novikov theorem and the Fox approach.By applying the two-state theory,the expression of the signal-to-noise ratio is obtained in the adiabatic limit.The effects of the noise parameters on signal-to-ratio are discussed.It is found that the stochastic resonance phenomena appear in most cases and disappear in some special cases. 相似文献
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Stochastic resonance (SR) in nonlinear systems is a counterintuitive concept in which a weak periodic signal and noise cooperate and give rise to a maximum in the signal-to-noise ratio at the output of the system when the noise is tuned to a certain value. In the coherence resonance phenomenon (CR), there is no deterministic signal to be enhanced. Intrinsic oscillations are present as transients. Adding an optimum noise turns transients into coherent ones. We discuss the possible application of SR and CR concepts to CDW dynamics in quasi-one dimensional conductors. We show in a preliminary experiment that addition of white noise can modify the behavior of the CDW in the quasi-one dimensional conductor K0.30MoO3. 相似文献
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We consider a one-dimension linear random walk between two trapping points in which the transition probabilities vary periodically in time. An earlier analysis of this system showed that the mean time to trapping of a particle in this system exhibits a minimum when considered as a function of frequency. In this note we show that this parameter makes a transition in behavior from a monotonic decrease with increasing amplitude of the periodic term to a monotonic increase with this parameter depending on the frequency. A physical argument is suggested to explain this behavior. Confirmation of this crossover can also be derived from a diffusion model. 相似文献
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In this paper, we report a novel effect of a particular kind of non-Gaussian noise (NGN), especially its deviation from Gaussian noise, on the spiking activity in a deterministic Hodgkin-Huxley (HH) neuron. It is found via numerical simulations that the coefficient of variation (CV), characterizing the spiking regularity, nonlinearly changes with varying deviation and passes through a minimum at an optimal deviation value, representing the presence of the coherence resonance (CR). This phenomenon shows that, when the NGN is optimal, the neuron can exhibit the most regular firing behavior. This result provides a constructive role of the NGN in the timing precision of information processing and signal transduction in neural systems. 相似文献
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R. Mingesz Z. Gingl P. Makra 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):339-344
On the basis of our mixed-signal simulations we report significant stochastic resonance induced input-output signal improvement
in the double-well system for aperiodic input types. We used a pulse train with randomised pulse locations and a band-limited
noise with low cut-off frequency as input signals, and applied a cross-spectral measure to quantify their noise content. We
also supplemented our examinations with simulations in the Schmitt trigger to show that the signal improvement we obtained
is not a result of a potential filtering effect due to the limited response time of the double-well dynamics. 相似文献
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The stochastic resonance (SR) is studied in an overdamped linear system driven by multiplicative and additive noise when the additive noise is a linear combination of an asymmetric dichotomous noise and its square. The exact expressions are obtained for the first two moments and the correlation function and the SR phenomenon appeared. There are three different forms of SR: the bona fide SR, the conventional SR and SR in the broad sense. Moreover, the asymmetry of multiplicative noise has different effect on signal-to-ratio (SNR) for the first two different forms of SR and the effects of multiplicative noise and additive noise on SNR are different. 相似文献
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Stochastic resonance in a single-mode laser driven by frequency modulated signal and coloured noises 下载免费PDF全文
By adding frequency modulated signals to the intensity equation of
gain--noise model of the single-mode laser driven by two coloured
noises which are correlated, this paper uses the linear
approximation method to calculate the power spectrum and
signal-to-noise ratio (SNR) of the laser intensity. The results show
that the SNR appears typical stochastic resonance with the variation
of intensity of the pump noise and quantum noise. As the amplitude
of a modulated signal has effects on the SNR, it shows suppression,
monotone increasing, stochastic resonance, and multiple stochastic
resonance with the variation of the frequency of a carrier signal
and modulated signal. 相似文献
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Both coherence resonance (CR) and stochastic resonance (SR) in a delayed bistable system driven by additive and multiplicative white noises and a weak harmonic excitation are studied by using the theory of two-state model. For the weak noise intensity and delayed feedback, the analytic expressions of power-spectrum and linear-spectrum amplification are derived to quantify the CR and the SR, respectively. The study shows that the peak in the power spectrum at the frequency corresponding to the time delay attains the maximum for an appropriate amount of additive noise intensity and the CR manifests. The feedback gain plays an important role in the SR. For example, the positive feedback gain enhances the SR, but the negative feedback gain suppresses the system output and makes the SR disappear. Moreover, the system also exhibits the frequency SR. 相似文献
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Entropic stochastic resonance in a confined structure driven by dichotomous noise and white noises 下载免费PDF全文
The entropic stochastic resonance(ESR) in a confined system subjected to dichotomous noise and white noise and driven by a periodic sinusoidal force along the x axis of the structure and a time-dependent force in the declining direction,is investigated.Under the adiabatic approximation condition and based on the two-state theory,the expression of the output signal-to-noise ratio(SNR) is obtained.The results show that the SNR is a non-monotonic function of the strengths of dichotomous noise,white noise,and correlated strength of correlated noise.In addition,the SNR varies non-monotonically with the increase of the shape parameters of the confined structure,and also with the increase of the constant force along the y axis of the structure.The influence of the correlation rate of the dichotomous noise,and that of the frequency of the periodic force on the SNR are discussed. 相似文献