I. Campos-Cantón

A SIMPLE CIRCUIT WITH DYNAMIC LOGIC ARCHITECTURE OF BASIC LOGIC GATES

We report experimental results obtained with a circuit possessing dynamic logic architecture based on one of the theoretical schemes proposed by H. Peng and collaborators in 2008. The schematic diagram of the electronic circuit and its implementation to get different basic logic gates are displayed and discussed. In particular, we show explicitly how to get the electronic NOR, NAND and XOR gates. The proposed electronic circuit is easy to build because it employs only resistors, operational amplifiers and comparators.

Forced synchronization of autonomous dynamical Boolean networks

We present the design of an autonomous time-delay Boolean network realized with readily available electronic components. Through simulations and experiments that account for the detailed nonlinear response of each circuit element, we demonstrate that a network with five Boolean nodes displays complex behavior. Furthermore, we show that the dynamics of two identical networks display near-instantaneous synchronization to a periodic state when forced by a common periodic Boolean signal. A theoretical analysis of the network reveals the conditions under which complex behavior is expected in an individual network and the occurrence of synchronization in the forced networks. This research will enable future experiments on autonomous time-delay networks using readily available electronic components with dynamics on a slow enough time-scale so that inexpensive data collection systems can faithfully record the dynamics.

A MULTIVIBRATOR CIRCUIT BASED ON CHAOS GENERATION

We present a parameterized method to design multivibrator circuits via piecewise-linear (PWL) chaotic systems, which can exhibit double-scroll oscillations. The circuit is conformed exploiting a parametric modulation that manipulates the equilibrium stability of each linear subsystem. Chuas oscillator is used as benchmark to illustrate the effectiveness of the proposed method to design multivibrator circuits. Thus, our proposal allows the design of the three configurations of a multivibrator: monostable, astable, and bistable. Potential applications are illustrated designing a pulse generator and a full S-R flip flop device based on our all-in-one multivibrator circuit.

Set-Reset Flip-Flop Circuit with a Simple Output Logic

The equation of the plane (EOP) in analytic geometry is used to build a logic dynamic architecture, i.e., a combination of set-reset flip-flop (SR-FF) and basic logic gates. This is achieved by using two of the variables in the EOP as the input signals of the SR-FF and the remaining variable as the output signal. This theoretical proposal for mixing the SR-FF and the basic logic gates is confirmed experimentally by means of a simple electronic implementation.

The Effects of Network Topology on Epidemic Algorithms

Epidemic algorithms can propagate information in a large scale network, that changes arbitrarily, in a self-organizing way. This type of spreading process allows rapid dissemination of information to all network nodes. However, the dynamics of epidemic algorithms can be strongly influenced by the network topology. In this paper, numerical simulations are used to illustrate such influences. We address networks with simple topologies for simplicity and in order to isolate other effects that occur in more complex networks.

Generation of a Reconfigurable Logical Cell Using Evolutionary Computation

In nature, an interesting topic is about how a cell can be reconfigured in order to achieve a different task. Another interesting topic is about the learning process that seems to be a trial and error process. In this work, we present mechanisms about how to produce a reconfigurable logical cell based on the tent map. The reconfiguration is realized by modifying its internal parameters generating several logical functions in the same structure. The logical cell is built with three blocks: the initial condition generating function, the tent map, and the output function. Furthermore, we propose a reconfigurable structure based on a chaotic system and an evolutionary algorithm is used in order to tune the parameters of the cell via trial and error process.

Application of dynamical system theory in LC harmonic oscillator circuits: A complement tool to the Barkhausen criterion

There are different types of electronic oscillators that have a wide variety of applications in areas such as computing, audio, communication, among others. One of these is the harmonic oscillators that generate an output sinusoidal signal. Due to the advantages of these, this paper proposes a methodology based on an analysis based on the dynamical system theory. This provides undergraduates a useful tool for a better understanding of the harmonic oscillators in order to design and implement accurately this kind of circuits. This tool complements the widely recognized Barkhausen criterion, which is a mathematical condition that must be satisfied by linear feedback oscillators. The analysis based on the dynamical system theory consists of obtaining a state matrix and its eigenvalues from the mathematical model of the oscillator circuits. The eigenvalues are adjusted to get an oscillator system, thus from this way, a set of conditions are derived. These conditions are complementary to those obtained by the Barkhausen criterion.

The region of attraction and exponentially uniform dynamics of HIV infection

The Human Immunodeficiency Virus (HIV) model used in this paper, describes a patients infection initial stage by means of a three-state-variable model. The dynamics of the patients evolution is analysed during a 500 day term, where the range of day-long transient response is clearly shown, and then the trend towards the asymptotic state is shown. This cell behavior is the patients state before patient develops AIDS. Based on that information, an estimate of the exponential uniform bound for perturbation, as well as the phase-space attraction region are shown. This information will be helpful for the physician personal in order to obtain a benign transient concerning the viral load dynamics. For the schedule of therapy it is desired.