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Modelado, medición y caracterización de inductores integrados

JOSÉ VALDÉS RAYÓN (2016)

Actualmente, las aplicaciones de RF trabajan con señales eléctricas que tienen frecuencias del rango de las microondas, permitiendo a los diseñadores de circuitos integrados utilizar dispositivos pasivos en un chip. Los inductores integrados más utilizados son los hechos con geometrías espirales, pues son compatibles con los procesos de fabricación de la tecnología CMOS. Sin embargo, éstos presentan desventajas tales como pérdidas por el substrato y un bajo factor de calidad. Una solución a estos problemas es la implementación de un escudo de tierra entre el dispositivo y el substrato. En la mayoría de sus aplicaciones este escudo está aterrizado, lo que genera un lazo de corriente entre el inductor y el escudo, dando lugar a una inductancia adicional.

Master thesis

Spiral inductors Intrinsic inductance Model T Model scalable CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA CIRCUITOS INTEGRADOS

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

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

Estimación de áreas vulnerables a inundaciones en zonas urbanas, caso: Morelia, Michoacán, México.

ANASTASIA ALARCON NEVA (2018)

Tesis (Maestría en Ciencias, especialista en Hidrociencias).- Colegio de Postgraduados, 2018.

Se presenta una técnica para definir áreas vulnerables a inundaciones, aplicada para la ciudad de Morelia, Michoacán, causadas por avenidas del el Río Grande de Morelia, que la cruza. Esta es una combinación de dos modelos: uno hidrológico, de precipitación-escurrimiento, HEC-HMS, en la cuenca hidrológica y uno hidráulico, IBER sobre el área de la ciudad de Morelia Michoacán, para delimitar áreas susceptibles a inundaciones, para avenidas esperadas con periodos de retorno, TRs, de 100 y 500 años. Se elaboró un Sistema de Información Geográfica como base para la delimitación, caracterizaron y modelación de la cuenca y subcuencas, hasta la Estación Hidrométrica Convencional, EHC, El Plan. El análisis estadístico de los registros históricos de precipitaciones máximas en 24 horas de 6 Estaciones Meteorológicas Convencionales, EMC, con influencia en la cuenca, se realizó con la Función de Distribución de Probabilidad Gumbel. Las distribuciones de la precipitación en 24 horas, en las 6 EMCs, se estimaron mediante la elaboración de hietogramas sintéticos correspondientes al mes de septiembre del 2013, aplicando hietogramas adimensionales de precipitaciones registradas en 2 Estaciones Meteorológicas Automáticas, EMAs, ubicadas en la cuenca. Las áreas susceptibles a inundación, para los TRs, considerados, se estimaron con el modelo hidráulico, utilizando topografía de campo, un modelo LIDAR y Coeficientes de Rugosidad de los cauces ubicados en y el que cruza la ciudad, con los hidrogramas de las avenidas obtenidos con el modelo hidrológico con el método de la Curva Numérica, CN. Los resultados permitieron estimar y mostrar razonablemente y en forma más localizada, áreas de la ciudad vulnerables a inundaciones por avenidas esperadas para los periodos de retorno considerados. _______________ ESTIMATION OF VULNERABLE ZONES TO FLOODING IN URBAN AREAS, CASE: CITY OF MORELIA, MICHOACÁN, MEXICO. ABSTRACT: A technique to define areas vulnerable to inundations, in the Morelia, Michoacán city caused by the runoff of the Rio Grande de Morelia, which crosses it, is presented. It is a combination of two models: one hydrologic, rainfall-runoff, HEC-HMS, in the Basin and one hydraulic, IBER on the area of the city of Morelia Michoacán, to delimit areas susceptible to floods, for expected runoffs for return periods, IRs, of 100 and 500 years. A geographic information system was developed as a basis for the delimitation, characterization and modeling of the basin and sub-basins, up to the conventional Hydrometric station, EHC, the Plan. Statistical analysis of the historical records of maximum rainfall in 24 hours of 6 conventional meteorological stations, EMC, with influence in the watershed, was performed with the Gumbel Probability Distribution Function. The precipitation distributions in 24 hours, in the 6 EMCs, were estimated trough Synthetic distribution hyetographs corresponding to the month of September of 2013, applying dimensionless distribution hyetographs calculated with rainfall records from 2 automatic meteorological stations, EMAs, located on the basin. The susceptible areas to flooding, for the considered IRs, were estimated with the hydraulic model, using field topography, a LIDAR model and roughness coefficients of tributaries located on and the river that crosses the city, with the hydrographs of the runoffs obtained with the hydrologic model with the Curve Number method. The results allowed to estimate and to show reasonably and in a more localized way, areas of the city vulnerable to flooding by expected runoffs, for the return periods considered.

Master thesis

Modelo Hietograma Estación meteorológica automática Hidrograma Gumbel Periodo de Retorno Model Hyetograph Automatic weather station Hydrograph Gumbel PDF Return periods Recurrence interval Hidrociencias Maestría CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO HIDROLOGÍA AGUAS SUPERFICIALES

Efficiency of quarantine and self-protection processes in epidemic spreading control on scale-free networks

JOSE DE JESUS ESQUIVEL GOMEZ JUAN GONZALO BARAJAS RAMIREZ (2018)

"One of the most effective mechanisms to contain the spread of an infectious disease through a population is the implementation of quarantine policies. However, its efficiency is affected by different aspects, for example, the structure of the underlining social network where highly connected individuals are more likely to become infected; therefore, the speed of the transmission of the decease is directly determined by the degree distribution of the network. Another aspect that influences the effectiveness of the quarantine is the self-protection processes of the individuals in the population, that is, they try to avoid contact with potentially infected individuals. In this paper, we investigate the efficiency of quarantine and self-protection processes in preventing the spreading of infectious diseases over complex networks with a power-law degree distribution [PðkÞ k] for different values. We propose two alternative scale-free models that result in power-law degree distributions above and below the exponent ¼ 3 associated with the conventional Barabasi-Albert model. Our results show that the exponent determines the effectiveness of these policies in controlling the spreading process. More precisely, we show that for the exponent below three, the quarantine mechanism loses effectiveness. However, the efficiency is improved if the quarantine is jointly implemented with a self-protection process driving the number of infected individuals significantly lower."

Article

Complex networks Model CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS MATEMÁTICAS

Occurrence of anticyclonic tornadoes in a topographically complex region of Mexico

JOSE NOEL CARBAJAL PEREZ José Francisco León Cruz Luis Felipe Pineda Martínez JOSE TUXPAN VARGAS JUAN HEBERTO GAVIÑO RODRIGUEZ (2019)

"Tornadoes are violent and destructive natural phenomena that occur on a local scale in most regions around the world. Severe storms occasionally lead to the formation of mesocyclones, whose direction or sense of rotation is often determined by the Coriolis force, among other factors. In the Northern Hemisphere, more than 99% of all tornadoes rotate anticlockwise. The present research shows that, in topographically complex regions, tornadoes have a different probability of rotating clockwise or anticlockwise. Our ongoing research programme on tornadoes in Mexico has shown that the number of tornadoes is significantly higher than previously thought. About 40% of all tornadoes occur in the complex topographic region of the Trans-Mexican Volcanic Belt. Data collected (from Internet videos) on the rotation of tornadoes formed in this region showed that about 50% of them rotated in a clockwise direction, contradicting tornado statistics for most of North America. Time series of the helicity parameter showed that tornadoes formed in topographically complex areas exhibited different behaviours compared to those formed in plains that are related with supercell systems."

Article

Meteorological analysis Convection Model Parameterization Thunderstorm Climatology Supercell India BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA