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Rabinovich M.I.,University of California at San Diego | Afraimovich V.S.,Institute Investigacion en Comunicacion optica | Varona P.,Autonomous University of Madrid
Dynamical Systems | Year: 2010

Here we consider a new mechanism of binding between different information modalities in the brain, i.e. heteroclinic binding. The basic model that we propose is able to explain the origin of the coordination of competitive dynamics of active brain modes representing the temporal processing of different sensory and/or intrinsic information (different modalities) in parallel. The model describes the coordination of spatio-temporal patterns in the form of sequential switchings corresponding to different modalities. We formulate the conditions for the existence of a multimodality heteroclinic sequence (MHS) in the phase space of this model. Such a sequence appears due to inhibitory connections between different sensory networks that implement a winnerless competition interaction. Computer simulations illustrate the robustness of the switching of the coordinated sequences for different modalities and their mutual regularization and modulation. © 2010 Taylor & Francis.

Esquivel-Gomez J.,Autonomous University of San Luis Potosi | Balderas-Navarro R.E.,Autonomous University of San Luis Potosi | Balderas-Navarro R.E.,Institute Investigacion en Comunicacion optica | Stevens-Navarro E.,Autonomous University of San Luis Potosi | Acosta-Elias J.,Autonomous University of San Luis Potosi
IEICE Transactions on Communications | Year: 2012

One of the most important constraints in wireless sensor networks (WSN) is that their nodes, in most of the cases, are powered by batteries, which cannot be replaced or recharged easily. In these types of networks, data transmission is one of the processes that consume a lot of energy, and therefore the embedded routing algorithm should consider this issue by establishing optimal routes in order to avoid premature death and eventually having partitioned nodes network. This paper proposes a new routing algorithm for WSN called Micro-Economic Routing Algorithm (MERA), which is based on the microeconomic model of supply-demand. In such algorithm each node comprising the network fixes a cost for relay messages according to their residual battery energy; and before sending information to the base station, the node searches for the most economical route. In order to test the performance of MERA, we varied the initial conditions of the system such as the network size and the number of defined thresholds. This was done in order to measure the time span for which the first node dies and the number of information messages received by the base station. Using the NS-2 simulator, we compared the performance of MERA against the Conditional Minimum Drain Rate (CMDR) algorithm reported in the literature. An optimal threshold value for the residual battery is estimated to be close to 20%. Copyright © 2012 The Institute of Electronics, Information and Communication Engineers.

Afraimovich V.S.,Institute Investigacion en Comunicacion optica | Shilnikov L.P.,Research Institute for Applied Mathematics and Cybernetics
International Journal of Bifurcation and Chaos | Year: 2014

We derive sufficient conditions for the existence of an invariant set in an absorbing region homeomorphic to the product of a multidimensional torus and a ball. This set consists of low dimensional tori labeled by symbolic sequences. It may appear as a result of the breakdown of an attracting multidimensional torus. Trajectories on the set manifest chaotic behavior for some angular coordinates and may behave regularly for others, i.e. the dynamics on the set is of the chimera state type. © 2014 World Scientific Publishing Company.

Rabinovich M.I.,University of California at San Diego | Afraimovich V.S.,Institute Investigacion en Comunicacion optica | Bick C.,Max Planck Institute for Dynamics and Self-Organization | Varona P.,Autonomous University of Madrid
Physics of Life Reviews | Year: 2012

Timing and dynamics of information in the brain is a hot field in modern neuroscience. The analysis of the temporal evolution of brain information is crucially important for the understanding of higher cognitive mechanisms in normal and pathological states. From the perspective of information dynamics, in this review we discuss working memory capacity, language dynamics, goal-dependent behavior programming and other functions of brain activity. In contrast with the classical description of information theory, which is mostly algebraic, brain flow information dynamics deals with problems such as the stability/instability of information flows, their quality, the timing of sequential processing, the top-down cognitive control of perceptual information, and information creation. In this framework, different types of information flow instabilities correspond to different cognitive disorders. On the other hand, the robustness of cognitive activity is related to the control of the information flow stability. We discuss these problems using both experimental and theoretical approaches, and we argue that brain activity is better understood considering information flows in the phase space of the corresponding dynamical model. In particular, we show how theory helps to understand intriguing experimental results in this matter, and how recent knowledge inspires new theoretical formalisms that can be tested with modern experimental techniques. © 2011.

Ramirez-Torres M.T.,Institute Investigacion en Comunicacion optica | Murguia J.S.,Autonomous University of San Luis Potosi | Carlos M.M.,Institute Investigacion en Comunicacion optica
International Journal of Modern Physics C | Year: 2014

This paper carries out the image encryption with a revised and modified cryptosystem based on a rule-90 cellular automaton. For this purpose, we used an appropriate and convenient matrix approach to implement the main components of the encryption system, two indexed families of permutations and a pseudo-random bit generator. Furthermore, we modify the encryption scheme for improving its security. This makes our encryption proposal resist some common attacks, e.g. chosen plain-text attack, and the encryption and decryption processes are performed in a flexible way. Also, some security aspects of the cryptosystem are evaluated with a series of statistical tests exhibiting good results. It is believed that this proposal fits naturally in the present digital technology and is capable of achieving high levels of performance. © 2014 World Scientific Publishing Company.

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