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Condición y posición de personas adultas mayores ante procesos migratorios en Chiautzingo, Puebla.

HIDALIA GARCÍA RÍOS (2019)

Tesis (Doctorado en Ciencias, especialista en Estrategias para el Desarrollo Agrícola Regional).- Colegio de Postgraduados, 2019.

En la investigación se analizan los efectos por género de procesos migratorios de hombres migrantes, habitantes de localidades del Municipio de Chiautzingo, Puebla, México, quienes se encuentran hoy, en situación de retorno y de mujeres integrantes del grupo doméstico en su condición y posición de género; y conocer la función social que ejercen, mediante las aportaciones desde el trabajo productivo y reproductivo que realizan mujeres y hombres durante su curso de vida, en sus trayectorias y transiciones. Se consideró en el análisis la interseccionalidad de género, parentesco, clase, generación y aspectos de orden estructural como la migración y la reproducción de la ideología de género. El estudio se realizó desde un enfoque cualitativo, con la aplicación de entrevistas en profundidad, observación participante, e identificación de informantes clave. Los y las sujetos de la investigación fueron 11 mujeres y 10 hombres adultos mayores, integrantes de grupos domésticos con procesos migratorios, hasta la obtención de la saturación teórica de acuerdo a las categorías de análisis. Se transcribió y analizó la información recabada. Se identificó que la condición y posición de género de las mujeres y hombres adultos mayores que vivieron procesos migratorios en su curso de vida, tuvo efectos diferenciales por género al interior del grupo doméstico, reproduciéndose desigualdades que ubican a las mujeres en situación de desventaja. La función social ejercida por los hombres y mujeres incluidos en la investigación afectó su condición y posición actual por construcciones sociales que afectan la valoración diferencial del trabajo que realizan. Pudieron identificarse en el curso de vida de las y los participantes en el estudio puntos de quiebre y toma de decisiones que trazaron sus trayectorias de vida, con diferencias y desigualdades entre los géneros. Se recomienda tomar en cuenta en el diseño de políticas las diferencias en la valoración del trabajo de hombres y mujeres para apuntar en disminuir la reproducción de las desigualdades aún en las políticas migratorias y las de combate a la pobreza. _______________ CONDITION AND POSITION OF OLDER ADULTS BEFORE MIGRATORY PROCESSES IN CHIAUTZINGO, PUEBLA. ABSTRACT: The aim of the research was to analyze the effects by gender of migratory processes of migrant men, inhabitants of localities of the Municipality of Chiautzingo, Puebla, Mexico, who are today, in a situation of return and of women members of the domestic group in their condition and position of gender; and to know the social function that they exert, by means of the contributions from the productive and reproductive work that women and men perform during their lifetime, in their trajectories and transitions. The intersectionality of gender, kinship, class, generation and structural aspects such as migration and the reproduction of gender ideology were considered and analyzed. The study was conducted from a qualitative approach, with the application of in-depth interviews, participant observation, and identification of key informants. The subjects of the investigation were 11 women and 10 older adult men, members of domestic groups with migratory processes, until obtaining theoretical saturation according to the analysis categories. The information collected was transcribed and analyzed. It was identified that the gender status and position of elderly women and men who experienced migratory processes in their lifetime, had gender differential effects within the domestic group, reproducing inequalities that place women at a disadvantage. The social function exercised by the men and women included in the research affected their current status and position by social constructions that affect the differential assessment of the work they perform. They were able to identify in the course of life of the participants in the study break points and decision making that traced their life trajectories, with differences and inequalities between the genders. It is recommended to take into account in the design of policies the differences in the valuation of the work of men and women to aim at reducing the reproduction of inequalities even in migration and poverty reduction policies.

Doctoral thesis

Género Función social Curso de vida Migración Grupo doméstico Chiautzingo, Puebla, México Gender Social function Life course Migration Domestic group Estrategias para el Desarrollo Agrícola Regional EDAR Doctorado CIENCIAS SOCIALES DEMOGRAFÍA CARACTERÍSTICAS DE LA POBLACIÓN ENVEJECIMIENTO DE LA POBLACIÓN

Límites indeterminados mediante el uso de tablas de valores y gráficas.

VICTOR IGNACIO ESPIRITU MONTIEL CATALINA NAVARRO SANDOVAL (2014)

This document proposes an alternative for calculating indeterminate limits through using tables of values and graphs, to pre-university students (aged between 17 and 18 years). For this, we have been given the task of analyzing research considering the historicalepistemological aspects, didactic and cognitive. Furthermore, was elaborated a questionnaire preliminary with the objective of exploring the procedures used by students to solve indeterminate limits, once applied and analyzed the results, we identified various problematic and according to these was designed a didactic proposal covering in particular the calculation of indeterminate limits, also presented in this paper, the results of the staging.

Article

Limit Indeterminate Function table of values graph HUMANIDADES Y CIENCIAS DE LA CONDUCTA PEDAGOGÍA OTRAS ESPECIALIDADES PEDAGÓGICAS

Caracterización eléctrica de tejido sanguíneo mediante función de transferencia

JOSE FRANCISCO GOMEZ AGUILAR JOSE DE JESUS BERNAL ALVARADO J. JUAN ROSALES GARCIA MANUEL GUIA CALDERON TEODORO CORDOVA FRAGA (2010)

En este trabajo se presenta un análisis y modelado de espectros de impedancia eléctrica aplicados al estudio de datos experimentales de tejido sanguíneo y sus principales componentes: glóbulos rojos, blancos y plasma. Usando la teoría de circuitos eléctricos se obtienen las funciones de transferencia y la representación gráfica de Bode y Nyquist. Se puede ver en este trabajo el potencial de la técnica experimental para diferenciar los elementos que forman al tejido sanguíneo, así como la utilidad de desarrollar modelos precisos para su análisis.

This paper presents an analysis and modeling of electrical impedance spectra applied to the study of experimental data of blood tissue and its main components: red cells, white and plasma. Using the electrical circuit theory yields the transfer functions and the graphic representation of Bode and Nyquist. You can see in this work the experimental technique’s potential to differentiate cellular components of blood tissue, and the usefulness of develo-ping accurate models for analysis.

Article

MEDICINA Y CIENCIAS DE LA SALUD Función de transferencia Diagrama de Bode Impedancia eléctrica Transfer function Bode diagram Electrical impedance

Realization of multiscroll chaotic attractors by using current-feedback operational amplifiers

RODOLFO TREJO GUERRA ESTEBAN TLELO CUAUTLE CARLOS SANCHEZ LOPEZ JESUS MANUEL MUÑOZ PACHECO (2010)

Multiscroll chaotic attractors are physically implemented by using commercially available current-feedback operational amplifiers (CFOAs). The values of the circuit elements are obtained systematically by a proposed technique based in the saturation of the CFOA to create Piece- Wise Linear (PWL) functions. Herein the technique is verified by Spice simulations and in experimental form by using CFOAs to generate n-scroll attractors in a systematic way. Lyapunov exponents are given to prove the chaotic behavior.

Se realiza la implementacion física de atractores caóticos de múltiples enrollamientos por medio del circuito comercial denominado amplificador operacional retroalimentado en corriente (CFOA). Los valores de los elementos del circuito son obtenidos sistemáticamente por medio de una técnica propuesta basada en la saturación del CFOA para generar funciones lineales a tramos (PWL functions). En este punto, la técnica es verificada por medio de simulaciones en Spice, así como de manera experimental utilizando CFOAs para generar atractores de n–enrollamientos de forma sistemática. Se presentan los exponentes de Lyapunov para corroborar el comportamiento caótico.

Article

n-scroll attractors Chua’s circuit Break point Lyapunov exponent CFOA PWL function Atractores n-enrollamientos Circuito de Chua Punto de quiebre Exponente de Lyapunov Función lineal a tramos CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

An extension of generalized linear models

EDUARDO GUTIERREZ GONZALEZ ANA LAURA REYES OLVERA (2011)

"In this paper, a general model is proposed to extend generalized linear models to non monotonic link functions. In order to determine the best model, different link function families are analysed, and through AIC, the best model is chosen. Moreover, using asymptotic properties of maximum likelihood estimates are calculated with confidence intervals and hypothesis tests for each of the parameters. Lastly, one example of regression extension is proposed for the bernoulli distribution applied to in vitro germination of leucocoryne coquimbensis seeds."

Article

Generalized linear model Link function AIC Bernoulli distribution CIENCIAS SOCIALES

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

Synthesis of piece-wise linear functions and its application to chaotic oscillators

RODOLFO TREJO GUERRA (2008)

Although chaotic systems were first introduced to describe dynamical behaviors by

modeling natural complex phenomena, they have been an important subject of research

during the last two decades mainly because of the growing of the computing available

resources. Nowadays, chaos research is present in very different fields to model complex

behaviors such as: behavior of the human being, the market prices until physical

relations between celestial corps, the modeling of fluids dynamics and information encrypting.

As many phenomena in nature, most of the chaotic systems can be described and

modeled by electrical circuits, which are then denoted as chaotic oscillators. There

are several known forms to implement them, the majority of the electronic realizations

are based on the use of operational amplifiers (Opamps) and in some cases, on more

complex blocks like those which realize mathematical operations just as multiplication

and division, with electrical signals mainly voltages.

Among all the kinds of chaotic oscillators, there is a set which only requires differential

operators and the use of destabilizing functions known as ”piece wise linear

functions” or PWL functions. Such kinds of systems are among the simplest to be

implemented by using electronic circuits; however, they are capable of achieving very

complex dynamics. On the other hand, the implementation of PWL-based chaotic oscillators

at the integrated circuit level, is becoming an important field of research. In this

manner, this Thesis is devoted to implement such PWL-based chaotic systems using

VLSI design techniques.

The main contribution of this work is related to the use of unity-gain cells to build

behavioral models and later to realize simulations using HSPICE and standard CMOS

technology of 0.35μm. This implies for an analog circuit designer to take into account

practical considerations with respect to the limited dynamical ranges, the system

bandwidth and other characteristics analyzed in the singular blocks which conform the

chaotic oscillator.

Si bien los sistemas caóticos fueron primero introducidos para describir comportamientos

dinámicos por medio del modelado de fenómenos naturales complejos, han sido

materia importante de investigación principalmente los últimos veinte años debido a

la facilidad del procesamiento de datos que se ha desarrollado en materia de cómputo.

Actualmente se desarrolla investigación en muy diversos campos para modelar comportamientos

complejos como: las conductas y patrones del ser humano, la fluctuación

de la economía hasta las relaciones físicas entre cuerpos celestes, el modelado de las

dinámicas de fluidos y el encriptamiento de información.

Al igual que muchos otros fenómenos en la naturaleza, la mayoría de los sistemas

caóticos se pueden describir y modelar por medio de circuitos, los cuales se denominan

osciladores caóticos. Existen varias formas de implementarlos, la mayoría de las realizaciones

electrónicas se basan en el uso de Amplificadores Operacionales (Opamps por

sus siglas en inglés) y en algunos casos, bloques más complejos para realizar operaciones

matemáticas tales como el producto o la división de señales eléctricas generalmente de

voltaje.

Entre todos los tipos de osciladores caóticos hay un conjunto que puede ser realizado

simplemente con las relaciones diferenciales entre sus variables y el uso de funciones

desestabilizantes conocidas como ”funciones lineales a tramos” o funciones PWL. Dichos

tipos de sistemas están entre los más sencillos para realizar por medio de circuitos

electrónicos; sin embargo, son capaces de producir dinámicas muy complejas. Por otro

lado, la implementación de sistemas caóticos basados en técnicas PWL a nivel de circuito

integrado se esta volviendo un importante campo de investigación. De esta forma, esta

tesis esta dedicada a implementar dichos sistemas caóticos PWL utilizando técnicas de

diseño VLSI.

La principal contribución de este trabajo está relacionada con el uso de celdas de

ganancia unitaria para construir modelos comportamentales y posteriormente realizar

simulaciones usando HSPICE y una tecnología CMOS estandard de 0.35μm. Esto implica

para el diseñador de circuitos analógicos el tomar consideraciones prácticas respecto

de los rangos dinámicos limitados, el ancho de banda, y otras características

analizadas en los bloques que conforman el oscilador caótico.

Master thesis

Chaos generators Piecewise linear techniques Function generators CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA DISEÑO DE FILTROS

Electron energy-loss spectroscopy of V2O5 nanofibers synthesized by electro-spinning

MARTHA TERESITA OCHOA LARA FRANCISCO ESPINOSA MAGAÑA (2013)

The dielectric properties of V2O5 nanofibers, synthesized by the electrospinning method, are studied by analyzing the low-loss region of the electron energy loss spectroscopy (EELS) in a transmission electron microscope. A comparison of experimental EELS spectra and ab initio density-functional theory calcula-tions (WIEN2k code) within the Generalized Gradient Approximation (GGA) is presented, having found an excellent agreement between them. Although the experimental EELS has been acquired for the nanopar-ticles composing the fibers, and numerical calculations were carried out for bulk material, agreement between experimental and calculated results shows that no difference exists between the electronic structure in calculated bulk material and the nanoparticles. Furthermore, our results from EELS confirm that we accomplished the expected crystalline phase. The origins of interband transitions are identified in the electronic band structure by calculating the partial imaginary part of the dielectric function and the partial density of states.

Article

EELS Dielectric function CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA OTRAS ESPECIALIDADES FÍSICAS OTRAS

Regularization of divergent integrals: A comparison of the classical and generalized-functions approaches

VOLODYMYR ZOZULYA (2015)

This article considers methods of weakly singular and hypersingular integral regularization based on the theory of distributions. For regularization of divergent integrals, the Gauss–Ostrogradskii theorem and the second Green’s theorem in the sense of the theory of distribution have been used. Equations that allow easy calculation of weakly singular, singular, and hypersingular integrals in one- and two-dimensional cases for any sufficiently smooth function have been obtained. These equations are compared with classical methods of regularization. The results of numerical calculation using classical approaches and those based of the theory of generalized functions, along with a comparison for different functions, are presented in tables and graphs of the values of divergent integrals versus the position of the colocation point.

Article

BEM BIE DIVERGENT GENERALIZED FUNCTION HYPERSINGULAR INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS

Optical matrix elements in tight-binding approach of hydrogenated Si nanowires

JOSE ALEJANDRO DIAZ MENDEZ MIGUEL CRUZ IRISSON (2009)

The dependence of the imaginary part of the dielectric function on the quantum confinement within two different schemes: intra-atomic and interatomic optical matrix elements are applied and compared. The optical spectra of Si nanowires are studied by means of a semi-empirical sp3s* tight-binding supercell model. The surface dangling bonds are passivated by hydrogen atoms. The results show that although the intra-atomic matrix elements are small in magnitude, the interference between these terms and the interatomic matrix elements contributes with nearly 25% of the total absorption. Thus, a quantitative treatment of nanostructures may not be possible without the inclusion of intra-atomic matrix elements.

Article

Silicon nanowires Tight-binding approach Dielectric function CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA