We consider patterns generated by adding large number of sand grains at a single site in an abelian sandpile model with a periodic initial configuration, and relaxing. The patterns show proportionate growth. We study the robustness of these patterns against different types of noise, viz., randomness in the point of addition, disorder in the initial periodic configuration, and disorder in the co...

Many neurons have epochs in which they fire action potentials in an approximately periodic fashion. To see what effects noise of relatively small amplitude has on such repetitive activity we recently examined the response of the Hodgkin-Huxley (HH) space-clamped system to such noise as the mean and variance of the applied current vary, near the bifurcation to periodic firing. This article is co...

Intracellular oscillators entrain to periodic signals by adjusting their phase and frequency. However, the low copy numbers of key molecular players make the dynamics of these oscillators intrinsically noisy, disrupting their oscillatory activity and entrainment response. Here, we use a combination of computational methods and experimental observations to reveal a functional distinction between...

Technical reports from the Automatic Control group in Linkping are available by anonymous ftp at the address ftp.control.isy.liu.se. This report is contained in the compressed postscript le 2044.ps.Z. Abstract The use of periodic excitation signals in identiication experiments is advocated. With periodic excitation it is possible to separate the driving signals and the disturbances , which for ...

We consider the problem of stochastic exit from a planar domain, whose boundary is an unstable periodic orbit, and which contains a stable periodic orbit. This problem arises when investigating the distribution of noise-induced phase slips between synchronized oscillators, or when studying stochastic resonance far from the adiabatic limit. We introduce a simple, piecewise linear model equation,...

Communications over power lines in the frequency range above 2 MHz, commonly referred to as broadband (BB) power line communications (PLC), is a central communications scenario for smart power grids. BB-PLC channels are characterized by a dominant colored non-Gaussian additive noise, as well as by periodic variations of the channel impulse response and the noise statistics, induced by the mains...

We study the variance of the solution of a periodic randomly perturbed one-dimensional Schrödinger operator after propagation through N periods. It is shown that if the frequency of propagation lies inside the band, then the total variance is proportional to Nσ 2, where σ is the intensity of the white noise. However, if the wave frequency is close to the band edge (where the transfer matrix has...

We demonstrate experimentally that noise can enhance the homeostatic function in the human blood pressure regulatory system. The results show that the compensatory heart rate response to the weak periodic signal introduced at the venous blood pressure receptor is optimized by adding noise to the arterial blood pressure receptor. We conclude that this functional stochastic resonance most likely ...

In this paper we study the effect that jitter and phase noise have on the precision of amplitude estimation of the harmonics of a periodic signal. The analysis carried out is applicable to both Three-Parameter Sine Fitting as well as Coherent Discrete Fourier Transform procedures. We consider the case where jitter and phase noise on the signal or sampling clock is small when compared with the s...

We have analyzed the interplay between noise and periodic modulations in a classical Lotka-Volterra model of two-species competition. We have found that the consideration of noise changes drastically the behavior of the system and leads to new situations which have no counterpart in the deterministic case. Among others, noise is responsible for temporal oscillations, spatial patterns, and the e...