José Luis Guisado

Universidad de Sevilla | US · Architecture and Computer Technology

The classical modeling approach for laser study relies on the differential equations. In this paper, a cellular automaton model is proposed as an alternative for the simulation of population dynamics. Even though the model is simplified it captures the essence of laser phenomenology: (i) there is a threshold pumping rate that depends inversely on t...

This thesis presents interdisciplinary research carried out in the areas of physics and computer science. We introduce a new model based on cellular automata (CA) to describe laser dynamics, which is an alternative to the standard description based on differential equations. We also study how to take advantage of the intrinsic parallel nature of CA...

Cellular automaton models of complex systems (CSs) are gaining greater popularity; simultaneously, they have proven the capability to solve real scientific and engineering applications. To enable everybody a quick penetration into the core of this type of modeling, three real applications of cellular automaton models, including selected open source...

We present a hybrid model combining cellular automata (CA) and agent-based modeling (ABM) to analyze the deployment of electric vehicle charging stations through microscopic traffic simulations. This model is implemented in a simulation tool called SIMTRAVEL, which allows combining electric vehicles (EVs) and internal combustion engine vehicles (IC...

In this paper we show how to efficiently implement parallel discrete simulations on multicore and GPU architectures through a real example of an application: a cellular automata model of laser dynamics. We describe the techniques employed to build and optimize the implementations using OpenMP and CUDA frameworks. We have evaluated the performance o...

In this paper, we present a cellular automata model for a two-level laser which includes a saturable absorber. We show that the model reproduces laser passive Q-switching, a behavior in which intense short pulses of laser radiation are produced. Depending on the concentration of the absorbent, the automaton model qualitatively reproduces two operat...

A Cellular Automaton is a bio-inspired discrete model of computation with multiple applications, consisting of a regular grid of cells that have different states along time. Our research group at the University of Seville (Spain) collaborated in the past with Prof. Mohammad S. Obaidat in the fusion of Cellular Automata (CA) with another bio-inspire...

Graphics Processing Units (GPUs) can be used as convenient hardware accelerators to speed up Cellular Automata (CA) simulations, which are employed in many scientific areas. However, an important set of CA have performance constraints due to GPU memory bandwidth. Few studies have fully explored how CA implementations can take advantage of modern GP...

Membrane computing is an unconventional computing paradigm that has gained much attention in recent decades because of its massively parallel character and its usefulness to build models of complex systems. However, until now, there was no generic hardware implementation of P systems. Computational frameworks to execute P systems up to this day rel...

In this paper we show how to efficiently implement parallel discrete simulations on Multi-Core and GPU architectures through a real example of application: a cellular automata model of laser dynamics. We describe the techniques employed to build and optimize the implementations using OpenMP and CUDA frameworks. We have evaluated the performance on...

The long-established approach to study laser dynamics uses a set of differential equations known as the laser rate equations. In this work we present an overview of an alternative model based on a cellular automaton (CA). We also present a panorama of different variants of the model: the original one, designed to simulate general laser dynamics; an...

Modelling real systems and processes is a task classically performed through the approach of diferential equation systems, defining the evolution of diferent variables as the diferent components of the system. A bad feature that diferential equations have is that if some new parameter has to be introduced in the system, then often the previous equa...

Understanding the regulation of gene expression is one of the key problems in current biology. A promising method for that purpose is the determination of the temporal dynamics between known initial and ending network states, by using simple acting rules. The huge amount of rule combinations and the nonlinear inherent nature of the problem make gen...

This paper presents a study of performance of RAM-based implementations in FPGAs of Finite State Machines (FSMs). The influence of the FSM characteristics on speed and area has been studied, taking into account the particular features of different FPGA families, like the size of LUTs, the size of memory blocks, the number of embedded multiplexer le...

We present a parallel implementation for Graphics Processing Units (GPUs) of a model based on cellular automata (CA) to simulate laser dynamics. A cellular automaton is an inherent parallel type of algorithm that is very suitable to simulate complex systems formed by many individual components which give rise to emergent behaviours. We exploit the...

Here we report new results of a genetic algorithm (GA) used to evolve one dimensional Cellular Automata (CA) to perform a P3 non-trivial collective behavior task. For this task the goal is to find a CA rule that reaches one final configuration in which the concentration of active cells oscillates among three different values. Though the majority of...

This chapter reviews the application of a biologically inspired heuristic technique - Cellular Automata (CA) - for developing high performance simulations of a well known complex system: the laser. CA can be described as a class of mathematical systems. They were introduced several decades ago, and are well suited to model spatio-temporal phenomen...

Introduction Background Laser Dynamics Problem Algorithmic Proposal Experimental Analysis Parallel Implementation of the Algorithm Conclusions References

In order to analyze the feasibility of executing a parallel bioinspired model of laser dynamics on a heterogeneous non-dedicated cluster, we evaluate its performance including artificial load to simulate other tasks or jobs submitted by other users. As the model is based on a synchronous cellular automaton (CA), using the SPMD (Single Program, Mult...

Firstly, the application of a cellular automata (CA) model to simulate the dynamics of lasers is reviewed. With this kind of model, the macroscopic properties of the laser system emerge as a cooperative phenomenon from elementary components locally interacting under simple rules. Secondly, a parallel implementation of this kind of model for distrib...

In this article an experience of the utilization of PRC (Public Resource Computation) in research projects that needs large quantities of CPU time is presented. We have developed a distributed architecture based on middleware BOINC and LilGP Genetic Programming tool. In order to run LilGP applications under BOINC platforms, some core LilGP func-tio...

EXPERIENCIAS EN EL DISEÑO DE PLANES DOCENTES EN CLAVE ECTS En este artículo presentamos una experiencia docente en el marco del nuevo Espacio Europeo de Educación Superior: la potenciación de las competencias transversales en un Plan Piloto de Ingeniería Técnica Informática de Sistemas (ITIS). Para ello se seleccionó una asignatura de tercer curso...

A parallel implementation for distributed-memory MIMD systems of a 2D discrete model of laser dynamics based on cellular automata is presented. The model has been implemented on a PC cluster using a message passing library. A good performance has been obtained, allowing us to run realistic simulations of laser systems in clusters of workstations, w...

This paper presents an analysis on the performance of a parallel implementation of a discrete model of laser dynamics, which is based on cellular automata. The performance of a 2D parallel version of the model is studied as a first step to test the feasibility of a parallel 3D version, which is needed to simulate specific laser systems. The 3D vers...

Laser dynamics simulations have been carried out using a cellular automata model. The Shannon's entropy has been used to study the different emergent behaviors exhibited by the system, mainly the laser spiking and the laser constant operation. It is also shown that the Shannon's entropy of the distribution of the populations of photons and electron...

The different kinds of behavior exhibited by the system in a laser dynamics simulation using a cellular automata model are analyzed. Three distinct types of behavior have been found: laser constant operation, laser spiking and a complex behavior showing irregular oscillations. In the last case, the power spectrum follows a power law of the type 1/f...

Laser dynamics is traditionally modeled using differential equations. Recently, a new approach has been introduced in which laser dynamics is modeled using two-dimensional Cellular Automata (CA). In this work, we study a modified version of this model in order to simulate the dynamics of pulsed pumped lasers. The results of the CA approach are in q...

This paper presents a new proposal for reducing bloat in Genetic Programming. This proposal is based in a well-known parallel evolutionary model: the island model. We firstly describe the theoretical motivation for this new approach to the bloat problem, and then we present a set of experiments that gives us evidence of the findings extracted from...

We investigate the relative importance of the Coulomb and nuclear fields to induce the break-up of neutron-rich nuclei such as 11Li at energies close to the Coulomb barrier. We assume that the mechanism that leads to the separation is the excitation of a low-lying dipole mode in which the weakly-bound neutron halo performs a collective oscillation...