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Autómata Celular Estocástico paralelizado por GPU aplicado a la simulación de enfermedades infecciosas en grandes poblaciones

Stochastic Cellular Automata approach for infectious disease simulation on large populations parallelized by GPU

HECTOR CUESTA ARVIZU Adrián Trueba Espinosa José Sergio Ruiz Castilla (2012)

Un gran número de áreas de la ciencia están siendo beneficiadas por la reducción de tiempo de cómputo gracias al uso de las Unidades Gráficas de Proceso (GPU). En el caso de la Epidemiología, tales unidades agilizan la simulación de escenarios con poblaciones grandes, escenarios en los que el tiempo de procesamiento es muy significativo. El presente artículo introduce la simulación de eventos epidemiológicos basado en un modelo de Autómatas Celulares Estocásticos (AC), el cual ofrece la implementación de las características principales de una enfermedad infecciosa a gran escala: contacto, vecindario, trayectorias y transmisibilidad. Un caso de estudio es simulado en una implementación del algoritmo AC para una enfermedad infecciosa de tipo SEIRS (Susceptible, Expuesto, Infectado, Recuperado y Susceptible). Una población de 1 000 000 de individuos es paralelizada a través de un algoritmo de balanceo de procesos implementado en el lenguaje de programación C-CUDA. El resultado dado por el software paralelizado por GPU es comparado contra un análisis hecho del modelo paralelizado por multi-hilos CPU. Los resultados demuestran que el tiempo de cómputo puede ser reducido significativamente gracias al uso de C-CUDA.

In science, a large number of areas are being benefited by the reduction of computational time with the use of Graphics Processing Units (GPU). In the case of Epidemiology, the benefit consists in the speedup of simulation of scenarios with bigger populations in which the processing time is large. This article introduces an epidemiological event simulation with a model based on Stochastic Cellular Automata (SCA). This model provides an implementation of the main features of a large-scale infectious disease: contact, neighborhood, trajectories and transmissibility. A case study is simulated on an implementation of the SCA algorithm for an infectious disease type SEIRS (Susceptible, Exposed, Infected, Recovered and Susceptible). A population with 1 000 000 of individuals is parallelized through a process balancing algorithm implemented in C-CUDA. The result given by the GPU parallelized software is compared against a parallelized model analysis made by multi-threaded CPU. The results show that the computation time can be significantly reduced through the use of C-CUDA.

Article

MEDICINA Y CIENCIAS DE LA SALUD Epidemiología Autómata Celular Modelo estocástico Simulación GPU (Unidades Gráficas de Proceso) Epidemiology Cellular Automata Stochastic model Simulation GPU (Graphics Processing Units)

Development of an analytical model for a charge-controlled memristor and its applications

Yojanes Andrés Rodríguez Velásquez (2017)

In this work, the development of an analytical model for a memristor is presented. The

model is based on the solution of the differential equation that governs the physical

behaviour of the device. The solution has been obtained by resorting to a homotopy

perturbation method.

The resulting memristance function is controlled by the electric charge, and full

symbolic expressions are obtained in function of the main parameters of the

memristor. The obtained model is characterised both for AC and DC sources. The main

fingerprints of the device in AC regime have been verified, as well as the main

parameters in DC (the switching voltages and saturation time).

In order to show the usefulness of the model, two applications that use memristive

grids as an analog processor, are studied. In a first application, the memristive grid is

used as a filter for image edge detection and smoothing, obtaining a good performance

in comparison with the edge recognition made by humans. In a second application,

the memristive grid is used in the maze solving problem, since the analog processor

implements the shortest path method.

En este trabajo se presenta el desarrollo de un modelo analítico para un memristor,

basado en la solución de la ecuación diferencial que rige el comportamiento físico del

dispositivo. La solución se obtiene utilizando el método de homotopía de perturbación.

La memristancia en este modelo es controlada por la carga eléctrica y se obtienen

expresiones puramente simbólicas en función de los principales parámetros del

memristor. El modelo obtenido es caracterizado tanto para fuentes de AC como DC. Se verifica

que el modelo cumple con las principales características en AC, y adicionalmente se

determinan los principales parámetros DC (los voltajes de conmutación y tiempo de

saturación). Con el fin de mostrar la utilidad del modelo, se estudian dos aplicaciones que utilizan

una red memristiva a modo de procesador analógico. En la primera, la red memristiva

se utiliza como filtro para suavizado y extracción de bordes en imágenes, mostrando un

buen desempeño al ser comparada con los bordes extraídos por seres humanos. En la

segunda aplicación, la red memristiva se utiliza en la solución de laberintos, ya que el

procesador analógico implementa el método de la trayectoria más corta.

Master thesis

Memristor Maze solving Model Image edge detection CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA DISEÑO DE CIRCUITOS

Computation of a model of laminates with interlaminar dramage

ALBERTO DIAZ DIAZ (2007)

In this paper, a model of laminated plates called M4-5N and validated in a previous paper is modified in order to take into account damage at the interfaces between layers. Displacement discontinuities at the interfaces are considered in the model. These discontinuities are calculated by means of a damage model. This damage model involves non linear equations. In order to compute the model, the LATIN method is employed. With this method, two sub-problems are considered: one is linear and the other is non linear. In the linear problem the non-linear equations of the model are linearized. By iterating the resolution of each sub-problem, one obtains the solution of the global problem. The method is then applied to the resolution of a free edge problem of a composite laminate. Calculations prove that the model can help predict delamination in these laminates.

Article

laminates model CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA OTRAS ESPECIALIDADES FÍSICAS OTRAS

Genealogy of human capital governance

FRANCISCO RUBEN SANDOVAL VAZQUEZ ELEAZAR VILLEGAS GONZALEZ Enrique Martínez Muñoz MARIA LUISA QUINTERO SOTO BEATRIZ LLAMAS ARECHIGA Cruz García Lirios TIRSO JAVIER HERNANDEZ GRACIA (2018)

The psychological studies of organizations, about human capital, have shown that this factor increases to the extent that the environmental demands are intensified, but it is the intellectual trait that acquires the greatest value when considered as the main intangible asset. of an organization. In this way, the objective of this paper was to expose the theoretical, conceptual and empirical frameworks related to human capital to establish discussion scenarios related to the value chain of an organization based on its intangible assets. A documentary study was carried out with a non-probabilistic selection of sources indexed to repositories such as Dialne , Latindex, Publindex, Redalyc and Scielo , considering the year of publication and relationship between the concepts of organization and human capital. There are lines of research around empathy, trust, commitment, satisfaction and happiness as inherent factors of human capital as an intellectual asset of an organization.

Article

Organization human capital intangible asset model specification CIENCIAS SOCIALES

Exploratory Category Structure of the Formation of Intellectual Capital

Eloisa Segura Ovalle MARIA LUISA QUINTERO SOTO HECTOR DANIEL MOLINA RUIZ FRANCISCO RUBEN SANDOVAL VAZQUEZ María Guadalupe Alvarado Ibarra Cruz García Lirios (2018)

The objective of the present work was to specify a model for the study of governance training. The theory intellectual capital essentially means that there is an indirect relationship between vocational training and job placement. Leadership styles are mediators in this process because they transfer values and norms that guide needs and expectations, as well as skills and knowledge to carry out the tasks and achieve the achievements. A non-experimental, documentary, cross-sectional and exploratory study was carried out with a selection of sources indexed to Latin American leading repositories, considering the publication period and ISSN and DOI registration; Dialnet, Latindex, Publindex, Redalyc and Scielo repositories. Since the specified model can be contrasted, the inclusion of factors such as empowerment and entrepreneurships are recommended to establish the scope and limits of the model.

Article

Human capital Vocational training Job placement Model Specification CIENCIAS SOCIALES

Data interactivity in social networks as a strategic design. An approach to Fair Trade

MIGUEL ANGEL RUBIO TOLEDO EMILIANO MORAS GOMEZ RICARDO VICTORIA URIBE ALEJANDRO HIGUERA ZIMBRON ARTURO SANTAMARIA ORTEGA ERIKA RIVERA GUTIERREZ SANDRA ALICIA UTRILLA COBOS (2014)

Nowadays and according to Ries (2006:14) the mass communication that has been implemented in a globalized world is branded by five ‘revolutions’ that have evolved the way the information is exchanged, allowing to share ideas or opinions of any kind with speed and ease. There is a direct correlation between each one of these mass communication revolutions that have been democratized and the start of a new interaction era. That way, such revolutions are defined by a particular mean of communication. These means are: 1) The book, which main characteristic is the information mass distribution as first communication revolution. 2) Newspapers, in which the main characteristic is the periodicity added to the mass distribution. This is the second revolution. 3) The radio broadcast, which has as characteristics the mass distribution, the immediacy and the audio. 4) Television, which adds to the previously mentioned characteristics the movement of images. 5) Finally the Internet, the fifth revolution implied a new element in the transmission of ideas: the interactivity.

Nowadays, the electronic means of communication have an unprecedented impact in the way of projects are developed. The electronic information –due to its nature– has now a more democratic approach of operation, plummeting the power of the great companies and governments. With the creation of the web 2.0, the common users of Internet have now a huge number of communication tools, which allow them to know –in an immediate, measured and effective way– what they or others think or believe. So, the object that has changed as a main channel is the operation by Internet. This current and simple –for many– phenomena, has a deep implication in the way of replanting the new paradigms with a global impact in productive projects as a commerce target.

Article

communication model internet strategic business CIENCIAS SOCIALES

Modelo de transporte para la logística de distribución de tuna (Opuntia spp) en fresco en México

JULIO CESAR AYLLON BENITEZ (2015)

Tesis (Maestría en Ciencias, especialista en Economía).- Colegio de Postgraduados, 2015.

En México la zona centro es la mayor productora de tuna a nivel nacional, en las zonas costeras, noreste, sur y sureste es bajo el consumo del fruto debido a la falta de distribución y al elevando costo de trasporte a estas zonas geográficas. Esta investigación se realizó en 2014, obteniendo la óptima distribución y rutas para comercializar el producto, utilizando el modelo de transporte correspondiente a técnicas matemáticas de la programación lineal, basado en el método de costo mínimo, asignando la mayor cantidad posible de oferta a menor costo unitario de zonas productoras a zonas consumidoras, planteándose dos escenarios, el primero es la dinámica del mercado cerrado y el segundo muestra la solución de mercado abierto. En los resultados se observa que solo cinco estados son autosuficientes, los cuales tienen la capacidad de ofrecer sus excedentes a los estados demandantes. Los costos de transporte demuestran como son proporcionales a las distancias recorridas, principalmente los estados productores del centro de la República Mexicana, existiendo clara restricción de distribución por su ubicación, por lo cual a partir del modelo se activaron las rutas que permitieron minimizarlos. _______________ TRANSPORT MODEL FOR THE LOGISTICS OF FRESH PRICKLY PEAR (Opuntia spp.) DISTRIBUTION IN MEXICO. ABSTRACT: The central part of Mexico is the national major producer of prickly pear; in the coastal areas, northeast, south and southeast, the consumption of this fruit is low due to lack of distribution and the high cost of transportation to these geographical zones. This research was carried out in 2014, using the optimum distribution and routes to trade the product, using the transport model that corresponds to mathematical techniques of linear programming, based on the minimum cost method, providing the widest possible offer at a lower unit cost from producer to consumption zones. It raised two sceneries, the first one is the closed market dynamic and the second one shows the solution of the open market. According to the results, it can be observed that only five states are self -sufficient, which have the capacity to offer their surplus to the demanding states. The costs of transportation demonstrate how they are proportional to the distances covered, mainly in the producer states of the central part of the Mexican Republic; it shows the existence of a clear restriction of distribution by its location, that is why, from this model, it was necessary to activate the routes that allowed to reduce the costs.

Master thesis

Optimización Programación lineal Modelo Optimization Linear programming Model Economía Maestría CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Analysis of the simulated global temperature using a simple energy balance stochastic model

LUIS EFRAIN MORELES VAZQUEZ BENJAMIN MARTINEZ LOPEZ (2016)

This work presents a study of the response of the simulated global temperature variability to additive and multiplicative stochastic parameterizations of heat fluxes, along with a description of the long-term variability in terms of simple autoregressive processes. The Earth’s global temperature was simulated using a globally averaged energy balance climate model coupled to a thermodynamic ocean model. It was found that simple autoregressive processes explain the temperature variability in the case of additive parameterizations; whereas in the case of multiplicative parameterizations, the description of the temperature variability would involve higher order autoregressive processes, suggesting the presence of complex feedback mechanisms originated by the multiplicative forcing. Also, it was found that multiplicative parameterizations produced a rich structure that emulates closely observed climate processes. Finally, a new approach to describe the stability in the steady state of a general one-dimensional stochastic system, through its potential function, was proposed. From an analytical expression of the potential function, further insight into the description of a stochastic system was provided.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Temperature variability stochastic parameterizations autoregressive process steady state potential function

Vuelo autónomo basado en estimadores estocásticos para mantener a un objetivo dentro del campo de visión

BEATRIZ HERNANDEZ HERNANDEZ (2017)

The use of drones in areas such as cinema, sports, social events and even military

areas has been increasing due to their exibility to capture video in scenarios where

there is an interest to keep a target within the field of view of the drones onboard

camera. In order to remove the dependence of the pilot that controls the drone, in

this work we present a system for an autonomous flight control of the drone with

the goal of keeping a target within the field of view of its onboard camera. For the

latter, the images were captured by a camera onboard the drone, whose output was

combined with a stochastic estimator of the target states, based on the Unscented

Kalman Filter, to generate control commands so that the drone performs such recording

autonomously. Two approaches are proposed, the first with the target seen from

the front of the drone and the second with the target seen from above by the drone.

Both approaches of the system were validated with real-time tests involving different

targets moving with different trajectories and compared against human pilots. For

the first approach, our system kept the target within the field of view with a 96.60%

of success and the second approach with a 92.05 %, compared to 83.30% and 89.13%

of success obtained by human pilots, respectively. The latter indicates that our approach

has the potential to be used in applications where autonomous drones could be used for

aerial video recording, with a special interest in keeping a target within

the field of view of the drone's camera.

El uso de los drones en áreas como el cine, deportes, eventos sociales e incluso

en áreas militares ha incrementado debido a su flexibilidad para capturar video en

escenarios donde hay un gran interés por mantener a un objetivo dentro del campo

de visión de la cámara a bordo del dron. Con el fin de eliminar la dependencia del

piloto que controla al dron, en este trabajo se presenta un sistema para el control

del vuelo autónomo del dron con el propósito de mantener a un objetivo dentro del

campo de visión de la cámara que tiene a bordo. Las imágenes fueron capturadas por

la cámara a bordo del dron y combinadas con un estimador estocástico de los estados

del objetivo, basado en el Filtro Kalman Unscented, para generar comandos de control

que permitan al dron realizar la grabación de forma autónoma. Se proponen dos

enfoques, el primero con el objetivo visto desde el frente del dron y el segundo con el

objetivo visto desde arriba por el dron. Ambos enfoques fueron validados con pruebas

en tiempo real que involucran a un objetivo que se mueve en diferentes trayectorias y

son comparadas con pilotos humanos. Para el primer enfoque, nuestro sistema mantiene

al objetivo dentro del campo de visión con un 96.60% de éxito y para el segundo

enfoque con un 92.05 %, mientras que el éxito obtenido con pilotos humanos es del

83.30% y del 89.13% respectivamente. Lo anterior, indica que nuestro enfoque tiene

el potencial para ser usado en aplicaciones en las que los drones autónomos pueden

ser utilizados para grabación aérea de video, con un especial interés por mantener a

un objetivo dentro del campo de visión de la cámara a bordo del dron.

Master thesis

Autonomous flight Stochastic estimators Kalman unscented filter Image processing CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA MICROELECTRÓNICA. DISEÑO

Segmentación de coberturas de la tierra espectralmente similares empleando campos aleatorios de Markov y características de textura estructural y estocástica

ERIKA DANAE LOPEZ ESPINOZA (2009)

In this thesis,Markovian modeling is applied to perform segmentation of land cover

from remote sensing and digital images. The segmentation problem is approached as a

classification problem, where the goal is to decompose an image in a set of homogeneous

regions using a similarity characteristics set.

In the Bayesian framework using Markov Random Fields (MRF) the image texture

is introduced as clique potentials of a second-order posterior energy function. These

clique potentials or texture fields are obtained by means of the 2-DWold decomposition

and the obtained final function is called texture energy function (TEF). Texture fields

are obtained from the frequency domain, therefore, a model is defined through both

the spatial (contextual constraint) and frequency (reference fields) domain. This model

allows us to define better the segmented image borders.

Experiments were carried out on a variety of synthetic and real images. From the

segmentation results, it is observed that by incorporating texture fields to the posterior

energy function, the segmentation quality is improved.

In this thesis, the main result is the TEF function which is possible to introduce

within MRF and tree-structured Markov random fields (TS-MRF) models. In this way,

a new model for segmentation of classes with similar spectral response based on TSMRF

and the TEF function is proposed.

In addition, a methodology that involves the TEF function and a stochastic geometry

model to improve image segmentation is proposed. The segmentation preliminary

results on synthetic images are encouraging, but there is still work to be done in this

direction.

En esta tesis se analiza el modelado Markoviano y su uso en la segmentación de

coberturas de la tierra a partir de imágenes para técnicas de percepción remota, sin dejar

a un lado el dominio de imágenes digitales en general. El problema de segmentación

lo consideramos análogo al de clasificación, donde el objetivo es dividir una imagen en

regiones homogéneas de acuerdo a un conjunto dado de características.

Bajo el enfoque Bayesiano usando campos aleatorios de Markov (MRF por sus

siglas en ingle´s), la textura de la imagen a ser segmentada se introduce como parte

de las funciones potenciales de la función de energía posterior de segundo grado. Los

campos de textura de la imagen segmentada son obtenidos mediante la descomposición

de Wold, y a la función final la llamamos Función de Energía de Textura o función

TEF por sus siglas en inglés. Al obtener los campos de textura en el dominio de las

frecuencias mediante la descomposición de Wold, la función propuesta queda definida

tanto en el dominio espacial (interacciones entre los píxeles) como en el dominio de las

frecuencias (campos de referencia). Lo anterior permite definir mejor los bordes de los

objetos que están siendo segmentados.

Una variedad de imágenes sintéticas y reales son segmentadas usando la función

TEF. A partir de los resultados de segmentación obtenidos se observa que, al incorporar

campos de textura en la función de energía posterior de losMRF se mejora el porcentaje

de segmentación.

La principal aportación en esta tesis es la función TEF la cual es posible introducir

en modelos de campos aleatorios deMarkov planos y de estructura de árbol (TS-MRF).

De esta manera en esta tesis se propone un nuevo modelo basado en TS-MRF y la

función TEF para segmentación de clases espectralmente similares.

Adicionalmente, se propone una metodología preliminar que involucra la función

TEF y un modelo de geometría estocástica para mejorar la segmentación de imágenes

con objetos geométricos. Los resultados de segmentación preliminares obtenidos sobre

imágenes sintéticas son alentadores, sin embargo existemucho trabajo por hacer en este

tema.

Doctoral thesis

Image segmentation Image texture Markov processes Remote sensing Spectral analysis Stochastic processes CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES