Showing papers in "Physica D: Nonlinear Phenomena in 1990"

TL;DR: In this paper, the problem of grounding symbolic representations in nonsymbolic representations of two kinds, i.e., "iconic representations" and "categorical representations" is addressed.

TL;DR: There is a fundamental connection between computation and phase transitions, especially second-order or “critical” transitions, and some of the implications for the understanding of nature if such a connection is borne out are discussed.

TL;DR: In this paper, an example of how simulated evolution can be applied to a practical optimization problem, and more specifically, how the addition of co-evolving parasites can improve the procedure by preventing the system from sticking at local maxima.

TL;DR: In this article, a simple coding of many attractors with clustering is shown, where the attractors are organized so that their change exhibits bifurcation-like phenomena, and a precision-dependent tree is constructed which leads to the similarity of our attractor with those of spin-glasses.

TL;DR: In this paper, the probability density function (PDF) of velocity differences between two points separated by distance r is studied and a new model for the PDF is developed which contains two parameters determined by experiments.

TL;DR: In this article, an explicit fourth-order method for the integration of Hamilton's equations is presented, which preserves the property that the time evolution of such a system yields a canonical transformation from the initial conditions to the final state.

TL;DR: In this article, a general framework is given for the phenomenological kinetics of phase transitions in which not only the order parameter but also the temperature may vary in time and space.

TL;DR: In this paper, the interaction of a pair of weakly nonlinear oscillators was investigated and it was shown that when the coupling strength is comparable to the attraction of the limit cycles, changes in amplitude cannot be ignored, and there are new phenomena.

TL;DR: In this paper, the authors considered model equations for the unidirectional propagation of small-amplitude, nonlinear, dispersive, long waves such as those governed by the classical Korteweg-de Vries equation.

TL;DR: In this article, the approximation of inertial manifolds for the one-dimensional Kuramoto-Sivashinsky equation (KSE) has been studied and a method motivated by the dynamics originally developed for the Navier-Stokes equation is adapted for the KSE.

TL;DR: In this paper, the authors solved an initial-boundary value problem for the Davey-Stewartson 1 equation, which is a two-dimensional generalization of the nonlinear Schrodinger equation and showed that the energy from the mean flow can be transferred to the surface envelope and create focusing effects.

TL;DR: In this paper, the relationship between the power law index α and the fractal dimension D for a time series following a power law spectrum is investigated by using a numerical experiment, and the relationships between α and D are also examined both for the differenced and for the integrated time series.

TL;DR: In this article, the authors consider a spatially extended field which evolves in time according to a PDE, and derive an asymptotic defect dynamics which derives from the full PDE.

TL;DR: In this article, the behavior of finitely many and infinitely many coupled weakly nonlinear oscillators is studied and it is shown that the uniform rest state can become stable if the coupling is sufficiently strong and the frequencies are sufficiently disparate.

TL;DR: In this paper, a rigorous proof is given in the standard map associated with a Frenkel-Kontorowa model for the existence of chaotic trajectories with unbounded momenta for large enough coupling constant k > k 0.

TL;DR: In this paper, the authors used cellular automata to model various physical phenomena normally modelled by wave equations, fluid dynamics, Ising models, etc., and found a single cellular automaton rule that models all of microscopic physics; and models it exactly.

TL;DR: The resulting Lyapunov exponent calculation provides a clear indication of chaos in seizure events, the definitive conclusion of which cannot be made from dimension calculations alone.

TL;DR: A truck is provided with a torsionally compliant transverse member connecting to transversely spaced side frames that are suspended on the axles by a spring suspension system of generally cylindrical elastomer elements and a combined damping system.

TL;DR: In this article, the authors present analytical methods which predict the occurrence of both soft (weak) and hard (strong) turbulence in the complex Ginzburg-Landau (CGL) equation: A t =RA+(1+iν)δA−( 1+iμ)A¦A 2 on a periodic domain [0,1] D in D spatial dimensions.

TL;DR: This paper provides a comprehensive, taxonomic survey of parallel simulated annealing techniques, highlighting their performance and applicability.

TL;DR: In this paper, the homoclinic geometric structure of the integrable sine-Gordon equation under periodic boundary conditions is developed and a physical interpretation of these states is given.

TL;DR: In this article, the authors investigate a novel type of bifurcation to chaos which occurs in the context of chaotic scattering, where the deflection angle versus impact parameter is singular on a set of impact parameters which is fractal.

TL;DR: This paper surveys results largely motivated by an attempt to answer questions posed by the approach to cellular automata by means of techniques from the former.

TL;DR: Previous work to extend previous work and simulate associative learning in a cytoskeletal network as well as assembly and disassembly of microtubules are extended and used as a means to model and demonstrate the potential for information processing in cytOSkeletal microtubule.

TL;DR: In this paper, a cellular automaton model of excitable media, recently introduced by the authors, is examined in more detail and it is shown that the model is consistent with a linear dependence of wave speed on wave-front curvature in two-dimensional space.

TL;DR: The Eckhaus instability has not been analyzed in bifurcation-theoretic terms as mentioned in this paper, but it can be studied analytically by averaging over the depth of the convection.

TL;DR: In this article, an artificial chemistry in the computer core is developed, where one is able to evolve assembler-automaton code without any predefined evolutionary path, and the system also has a notion of local computational resources.

TL;DR: In this paper, an adaptive control algorithm was proposed for multi-parameter and higher-dimensional nonlinear systems, where the recovery time is linearly proportional to the inverse of control stiffness.

TL;DR: In this article, the authors define a connectionist model as a dynamical system with two properties: (1) the interactions between the variables at any given time are explicitly constrained to a finite list of connections; and (2) the connections are fluid, in that their strength and/or pattern of connectivity can change with time.