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101.
Y. Pomeau 《Journal of statistical physics》1993,70(5-6):1379-1382
I propose an explanation of the observation of a globally synchronized behavior of deterministic cellular automata and coupled map lattices, together with local fluctuations. 相似文献
102.
The Magicicada spp. life cycles with its prime periods and highly synchronized emergence have defied reasonable scientific explanation since its discovery. During the last decade several models and explanations for this phenomenon appeared in the literature along with a great deal of discussion. Despite this considerable effort, there is no final conclusion about this long standing biological problem. Here, we construct a minimal automaton model without predation/parasitism which reproduces some of these aspects. Our results point towards competition between different strains with limited dispersal threshold as the main factor leading to the emergence of prime numbered life cycles. 相似文献
103.
Cellular instabilities of expanding hydrogen/propane spherical flames at elevated pressures: theory and experiment 总被引:1,自引:0,他引:1
An experimental and theoretical investigation of the onset of cellular instabilities on spherically expanding flames in mixtures of hydrogen and propane in air at elevated pressures was conducted. Critical conditions for the onset of instability were measured and mapped out over a range of pressures and mixture compositions. An asymptotic theory of hydrodynamic and diffusional-thermal cell development on flames in mixtures comprised of two scarce fuels burning in air was also formulated. Predicted values of Peclet number, defined as the flame radius at the onset of instability normalized by the flame thickness, were shown to compare favorably with the experimentally measured values. 相似文献
104.
105.
Daniel H. Rothman 《Journal of statistical physics》1989,56(3-4):517-524
A new irreversible collision rule is introduced for lattice-gas automata. The rule maximizes the flux of momentum in the direction of the local momentum gradient, yielding a negative shear viscosity. Numerical results in 2D show that the negative viscosity leads to the spontaneous ordering of the velocity field, with vorticity resolvable down to one lattice-link length. The new rule may be used in conjunction with previously proposed collision rules to yield a positive shear viscosity lower than the previous rules provide. In particular, Poiseuille flow tests demonstrate a decrease in viscosity by more than a factor of 2. 相似文献
106.
Roberto H. Schonmann 《Journal of statistical physics》1990,58(5-6):1239-1244
Cellular automata in two dimensions that generalize the bootstrap percolation dynamics are considered, focusing on the thresholdp
c of the initial density for convergence to total occupancy to occur; these models are classified according top
c being 0, 1, or strictly between these extreme values. Explicit upper and lower bounds are provided in the third case. 相似文献
107.
108.
We obtain cluster expansions for small random perturbations of deterministic Toom's automata in the one-dimensional case. Exponential convergence follows. Analyticity of invariant measures is examined as well as the simplest multidimensional case. 相似文献
109.
Maria Madjarova Mitsugu Kakuta Takashi Obi Masahiro Yamaguchi Nagaaki Ohyama 《Optical Review》1998,5(3):143-151
Pseudo-random properties of a class of two-dimensional (2-D) 5-neighborhood cellular automata (CA), built around nonlinear (OR, AND) and linear (XOR) Boolean functions are studied. The site values at each step of the 2-D CA evolution are taken in parallel and form pseudo-random sequences, which satisfy the criteria established for pseudo random number generator (PRNG): long period, excellent random qualities, single bit error propagation (avalanche criteria), easy and fast generation of the random bits. A block-scheme for secure Stream Cipher based on 2-D CA is proposed. The 2-D CA based PRNG algorithm has simple structure, use space-invariant and local interconnections and can be easily realized in very large scale integration or parallel optoelectronic architectures. 相似文献
110.
A. Bershadskii E. Dremencov D. Fukayama G. Yadid 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,24(3):409-413
Probabilistic properties of spiking time-series obtained in vivo from singular neurons belonging to Red Nucleus of brain are analyzed for two groups of rats: genetically defined rat model
of depression (Flinders Sensitive Rat Line - FSL) and a control (healthy) group. The FSL group shows a distribution of interspike
intervals with a much longer tail than that found for normal rats. The former distribution (for the FSL group) indicates a
power-law with exponent α = - 1±0.1. A simple thermodynamic (noise) model is elaborated to explain obtained results.
Received 13 May 2001 and Received in final form 20 September 2001 相似文献