Transient behaviour in the human voice is discussed, with particular reference to pitch breaks. Several nonlinear models for vocal fold vibration are proposed and discussed. One particular pitch break where a triple period emerges out of a double period — and vice versa — is modeled with a simple third order system similar to the Rössler system. For a given parameter value, the proposed model s...

Animal navigation is accomplished by a combination of landmark-following and dead reckoning based on estimates of self motion. Both of these approaches require the encoding of heading information, which can be represented as an allocentric or egocentric azimuthal angle. Recently, Ca2+ correlates of landmark position and heading direction, in egocentric coordinates, were observed in the ellipsoi...

Here, formation of continuous attractor dynamics in a nonlinear recurrent neural network is used to achieve a nonlinear speech denoising method, in order to implement robust phoneme recognition and information retrieval. Formation of attractor dynamics in recurrent neural network is first carried out by training the clean speech subspace as the continuous attractor. Then, it is used to recogniz...

We consider a hydrodynamic system that models the Smectic-A liquid crystal flow. The model consists of the Navier-Stokes equation for the fluid velocity coupled with a fourth-order equation for the layer variable φ, endowed with periodic boundary conditions. We analyze the long-time behavior of the solutions within the theory of infinite-dimensional dissipative dynamical systems. We first prove...

The notion of attractor networks is the leading hypothesis for how associative memories are stored and recalled. A defining anatomical feature of such networks is excitatory recurrent connections. These "attract" the firing pattern of the network to a stored pattern, even when the external input is incomplete (pattern completion). The CA3 region of the hippocampus has been postulated to be such...

This letter reports a study on some topological properties of chaos using a generalized competitive mode (GCM). The Lorenz system and the Chen system are used as examples for comparison. It is shown that for typical parameter values used in the two systems, the Lorenz attractor has one pair of GCMs in competition, while the Chen attractor has two pairs of GCMs in competition. This explains why ...

Recently, the study of chaotic dynamics has evolved from the traditional trend of understanding and analyzing chaos to the new intention of controlling and utilizing it [Chen & Dong, 1998; Wang & Chen, 2000; Lü et al., 2002d]. The Lorenz system, found in 1963, produces the best-known canonical chaotic attractor in a simple three-dimensional autonomous system [Lorenz, 1963; Stewart, 2000]. In 19...

This report examines how the relative attractor strengths of children's display of three emotion states, anger, sadness/fear, and neutral-engaged, are associated with exposure to maternal negative affect and care giving disruptions, and to child antisocial behavior and depression. Exposure to negative maternal affect was associated with a weaker attractor state for sadness or fear displays ...

We propose a new model for the time evolution of livestock commodities which exhibits endogenous deterministic stochastic behaviour. The model is based on the Yoccoz-Birkeland integral equation, a model first developed for studying the time-evolution of single species with high average fertility, a relatively short mating season and density dependent reproduction rates. This equation is then co...