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Sea surface temperature and mixed layer depth changes due to cold-air outbreak in the gulf of México

ELBA ELSA VILLANUEVA URRUTIA VICTOR MANUEL MENDOZA CASTRO JULIAN JORGE ADEM CHAHIN (2010)

The impact of a cold-air outbreak (CAO) on the mixed layer in the Gulf of México (GoM), during the period 18-23 October 1999, is shown in this work. A numerical model, based on the thermal energy equation and the balance equation between the thermal and mechanical energies, is used for computing both, the sea surface temperature (SST) and the sea mixed layer depth (MLD) changes due to atmospheric forcing before and during the CAO. The importance of the contributions to the temperature tendency by thermal forcing at the surface, the vertical entrainment of cold water from the thermocline, the horizontal transport of thermal energy by ocean currents and by turbulent eddies in the mixed layer are analyzed, as well as the contributions to the entrainment velocity by deepening of the mixed layer and the Ekman's pumping velocity. During the passage of the CAO on the Gulf of México the SST changes were markedly influenced by the increase in the surface wind speed. At the end of the period the experiments show that the vertical entrainment turned out to be the most determining process in the cooling of the mixed layer, even overhead of the latent and sensible heat fluxes and the horizontal transport by ocean currents and by turbulent eddies.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Sea surface temperature mixed layer depth cold-air outbreak Gulf of México

Sea surface temperature and mixed layer depth changes due to cold-air outbreak in the gulf of México

ELBA ELSA VILLANUEVA URRUTIA VICTOR MANUEL MENDOZA CASTRO JULIAN JORGE ADEM CHAHIN (2010)

The impact of a cold-air outbreak (CAO) on the mixed layer in the Gulf of México (GoM), during the period 18-23 October 1999, is shown in this work. A numerical model, based on the thermal energy equation and the balance equation between the thermal and mechanical energies, is used for computing both, the sea surface temperature (SST) and the sea mixed layer depth (MLD) changes due to atmospheric forcing before and during the CAO. The importance of the contributions to the temperature tendency by thermal forcing at the surface, the vertical entrainment of cold water from the thermocline, the horizontal transport of thermal energy by ocean currents and by turbulent eddies in the mixed layer are analyzed, as well as the contributions to the entrainment velocity by deepening of the mixed layer and the Ekman's pumping velocity. During the passage of the CAO on the Gulf of México the SST changes were markedly influenced by the increase in the surface wind speed. At the end of the period the experiments show that the vertical entrainment turned out to be the most determining process in the cooling of the mixed layer, even overhead of the latent and sensible heat fluxes and the horizontal transport by ocean currents and by turbulent eddies.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Sea surface temperature mixed layer depth cold-air outbreak Gulf of México

On the annual cycle of the sea surface temperature and the mixed layer depth in the Gulf of México

VICTOR MANUEL MENDOZA CASTRO ELBA ELSA VILLANUEVA URRUTIA JULIAN JORGE ADEM CHAHIN (2005)

Using an integrated mixed layer model we carry out a simulation of the annual cycle of the sea surface temperature (SST) and of the mixed layer depth (MLD) in the Gulf of México. We also compute the annual cycle of the entrainment velocity in the deepest region of the Gulf of México. The model is based on the thermal energy equation and on an equation of mechanical and thermal energy balance based on the Kraus- Turner theory; both equations are coupled and are vertically integrated in the mixed layer. The model equations are solved in a uniform grid of 25 km in the Gulf of México, the northwestern region of the Caribbean Sea and the eastern coast of Florida. The surface ocean current velocity and the atmospheric variables are prescribed in the model using observed values. We show the importance of the Ekman pumping in the entrainment velocity. We found that the upwelling plays an important role in increasing the entrainment velocity, producing an important reduction in the SST and diminishing the depth of the mixed layer in the Campeche Bay. In the rest of the Gulf of México the downwelling tends to reduce the entrainment velocity, increasing the SST and the MLD. Comparison of the computed annual cycle of the SST and the MLD with the corresponding observations reported by Robinson (1973), shows a good agreement. In the deepest region of the Gulf of México, the photosynthetic pigment concentration data obtained from the Mexican Pacific CD-ROM of environmental analysis shows significative correlation with the computed annual cycle of the computed entrainment velocity only in January, April, May, June and September.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Sea surface temperature mixed layer depth Gulf of Mexico

On the annual cycle of the sea surface temperature and the mixed layer depth in the Gulf of México

VICTOR MANUEL MENDOZA CASTRO ELBA ELSA VILLANUEVA URRUTIA JULIAN JORGE ADEM CHAHIN (2005)

Using an integrated mixed layer model we carry out a simulation of the annual cycle of the sea surface temperature (SST) and of the mixed layer depth (MLD) in the Gulf of México. We also compute the annual cycle of the entrainment velocity in the deepest region of the Gulf of México. The model is based on the thermal energy equation and on an equation of mechanical and thermal energy balance based on the Kraus- Turner theory; both equations are coupled and are vertically integrated in the mixed layer. The model equations are solved in a uniform grid of 25 km in the Gulf of México, the northwestern region of the Caribbean Sea and the eastern coast of Florida. The surface ocean current velocity and the atmospheric variables are prescribed in the model using observed values. We show the importance of the Ekman pumping in the entrainment velocity. We found that the upwelling plays an important role in increasing the entrainment velocity, producing an important reduction in the SST and diminishing the depth of the mixed layer in the Campeche Bay. In the rest of the Gulf of México the downwelling tends to reduce the entrainment velocity, increasing the SST and the MLD. Comparison of the computed annual cycle of the SST and the MLD with the corresponding observations reported by Robinson (1973), shows a good agreement. In the deepest region of the Gulf of México, the photosynthetic pigment concentration data obtained from the Mexican Pacific CD-ROM of environmental analysis shows significative correlation with the computed annual cycle of the computed entrainment velocity only in January, April, May, June and September.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Sea surface temperature mixed layer depth Gulf of Mexico

Effect of an axially-symmetric cyclonic vortex on the sea surface temperature in the Gulf of México

ELBA ELSA VILLANUEVA URRUTIA VICTOR MANUEL MENDOZA CASTRO JULIAN JORGE ADEM CHAHIN (2006)

A model for the mixed layer of the Gulf of México has been used to determine the effect that an idealized cyclonic vortex has in the sea surface temperature. The model consists of the equations of conservation of thermal energy and this of balance between mechanical energy and thermal energy, last based on the Kraus- Turner theory; both equations are vertically integrated in the mixed layer. As atmospheric forcing, we prescribe the surface wind associated with an axially-symmetric cyclonic vortex characterized by two parameters: the maximum tangential velocity and the radius at which that velocity is reached. The values of these two parameters, which depend on the position of the vortex, correspond to two cases: hurricane Hilda, which crossed the central part of the Gulf of México between September 29 and October 3, 1964 and hurricane Gilbert whose trajectory between 11 and 17 September, 1988 crossed the Caribbean Sea, the Yucatán Peninsula and the southwest Gulf of México. The results show that a cyclonic vortex with such characteristics, produce during its passage by the sea vertical turbulent water transport through the thermocline (entrainment) that is able to cool down the mixed layer in several degrees and increases the thermocline depth in several meters, in agreement with the observations.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Gulf of México sea surface temperature mixed layer numerical model atmospheric forcing entrainment

Effect of an axially-symmetric cyclonic vortex on the sea surface temperature in the Gulf of México

ELBA ELSA VILLANUEVA URRUTIA VICTOR MANUEL MENDOZA CASTRO JULIAN JORGE ADEM CHAHIN (2006)

A model for the mixed layer of the Gulf of México has been used to determine the effect that an idealized cyclonic vortex has in the sea surface temperature. The model consists of the equations of conservation of thermal energy and this of balance between mechanical energy and thermal energy, last based on the Kraus- Turner theory; both equations are vertically integrated in the mixed layer. As atmospheric forcing, we prescribe the surface wind associated with an axially-symmetric cyclonic vortex characterized by two parameters: the maximum tangential velocity and the radius at which that velocity is reached. The values of these two parameters, which depend on the position of the vortex, correspond to two cases: hurricane Hilda, which crossed the central part of the Gulf of México between September 29 and October 3, 1964 and hurricane Gilbert whose trajectory between 11 and 17 September, 1988 crossed the Caribbean Sea, the Yucatán Peninsula and the southwest Gulf of México. The results show that a cyclonic vortex with such characteristics, produce during its passage by the sea vertical turbulent water transport through the thermocline (entrainment) that is able to cool down the mixed layer in several degrees and increases the thermocline depth in several meters, in agreement with the observations.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Gulf of México sea surface temperature mixed layer numerical model atmospheric forcing entrainment

Desarrollo del sector microfinanciero en México

EVELINA ALVAREZ GONZALEZ (2013)

Tesis (Maestría en Ciencias, especialista en Economía).- Colegio de Postgraduados, 2013.

El propósito de este trabajo fue analizar el desarrollo y desempeño del sector microfinanciero en México durante el periodo de 1996-2012, mediante los indicadores profundidad y amplitud con el objetivo de conocer sobre que niveles de pobreza están realmente incidiendo las instituciones de microfinanzas en nuestro país y como se está comportando el mercado de prestatarios. El estudio se realizó con una muestra correspondiente a 120 IMF´S (Instituciones de Microfinanzas) mexicanas registradas y disponibles en las bases de datos de Microfinance Information Exchange, Inc. (Mix). y ProDesarrollo, Finanzas y Microempresa A.C. (Benchmarking 2012), para lo cual se empleo una metodología de tipo cuantitativa analítica con grupos de control y de estudio para facilitar el análisis, en el cual las variables consideradas en profundidad fueron: sexo, tamaño de crédito y ubicación. Y para amplitud: numero de prestatarios activos. Los resultados indican que el nivel de pobreza sobre el cual están trabajando las instituciones microfinancieras es bajo, pero apenas lo suficientemente bajo como para garantizar el retorno de los prestamos. Y en cuanto a el número de prestatarios se advierte un crecimiento positivo a lo largo del periodo pero en los últimos años solamente constante y sostenido lo que hace evidente que el sector se encuentra en un proceso de expansión y constante cambio. Se concluye que el sector microfinanciero mexicano, si bien esta incidiendo en el combate a la pobreza, el empoderamiento de la mujer y el incremento en la participación financiera por parte de una población tradicionalmente excluida de la banca convencional, lo hace de forma discreta y básica, por lo tanto los retos del aun joven sector son numerosos y de ello depende su supervivencia en los próximos años. _______________ DEVELOPMENT OF THE MICROFINANCIAL SECTOR IN MEXICO. ABSTRACT: The purpose of this study was to analyze the development and performance of the microfinance sector in Mexico during the period 1996-2012, by depth and breadth indicators in order to learn about that poverty levels are really affecting microfinance institutions in our country and as the market is behaving borrowers. The study was conducted with a sample corresponding to 120 Mexican IMF´S registered and available in databases Microfinance Information Exchange, Inc. (Mix). and ProDesarrollo, Finance and Micro B.C. (Benchmarking 2012)., For which we use a methodology for a quantitative analytical and control groups to facilitate analysis studies, in which the variables considered in depth were: sex, size and location credit. And for amplitude: number of active borrowers. The results indicate that the level of poverty they are working on microfinance institutions is low but just low enough to ensure the return of loans. As for the number of borrowers have seen a positive growth throughout the period but in recent years only constant and sustained it becomes clear that the sector is in a constant process of expansion and change. We conclude that the Mexican microfinance industry, although this impacting on poverty alleviation, empowerment of women and increased financial participation by a population traditionally excluded from conventional banking, it does so basic discrete therefore challenges still young industry are numerous and their survival depends on it in the coming years.

Master thesis

Microfinanzas Profundidad Amplitud Pobreza Microfinance Depth Breadth Poverty Economía Maestría CIENCIAS SOCIALES

Flujos de calor y momentum a través de la superficie en el Golfo de California

Surface heat and momentum fluxes in the Gulf of California

JESUS MANUEL FIGUEROA RODRIGUEZ (1991)

"Con datos meteorológicos colectados en 11 campañas hidrográficas realizadas en el golfo de California entre octubre de 1981 y diciembre de 1986, empleando fórmulas empíricas se calculan los flujos superficiales de calor y momentum, y se estudia su comportamiento temporal (interanual y estacional) y espacial. Si bien la información disponible es insuficiente para hacer una descripción completa, permite encontrar algunas tendencias generales. Los distintos flujos aquí estudiados muestran la presencia de una señal estacional y la existencia de diferencias regionales apreciables. El golfo gana más calor neto en verano que en invierno, y globalmente no pierde calor en ninguno de los meses aquí estudiados. Se encuentra que los altos valores de calor neto en verano no son nece sanamente resultado de surgencias, sino tal vez de frentes térmicos que inhiben la evaporación (reducen el flujo de calor latente) y reducen o anulan el flujo de calor sensible, o incluso invierten su sentido. Los bajos valores de calor neto en invierno y la alta evaporación apoyan la hipótesis del hundimiento convectivo en el alto golfo como factor contribuyente a la formación de la masa de agua del golfo. Contrariamente a lo que se pensaba, el flujo de calor latente hacia la atmósfera tiene una participación mas bien modesta (7% de la radiación solar de onda corta) en el balance de calor en el golfo de California, lo cual sugiere que el golfo no es una cuenca de evaporación y determina en cierta medida que, durante un ciclo anual, el balance sea una ganancia considerable de calor. De este modo, el golfo debe exportar más calor por convección hacia el Pacifico adyacente de lo que se ha supuesto. Con los datos de 1983 se establece. en términos generales, el efecto que sobre los flujos de calor tiene el fenómeno El Niño en el golfo de California; mientras que con los correspondientes a 1985 se analiza la influencia que sobre éstos tiene un frente térmico detectado en la región de las islas. En cuanto a los flujos de momentum, la calidad y la cantidad de los datos no permite hacer conclusiones que sean sostenibles ya que los patrones no son claros ni muestran tendencias definidas."

"Meteorological data gathered during eleven cruises in the Gulf of California (between October 1981 and December 1986) are used to calculate (on the basis of empirical formulae) surface heat and momentum fluxes. Their spatial and temporal distribution are studied. The available information is not enough to make a complete description of the fluxes, but a few general tendencies are found. The presente of a seasonal signal is evident and very Sharp spatial gradients are present. In the general heat balance, latent heat fluxes represent a very small part (7% of the shortwave radiation). This implies that the Gulf is not an evaporation basin and that in an annual cycle it must gain heat across the surface and, in order to be in balance, heat must be exported across the Guifs mouth to the Pacific Ocean."

Article

Capa mezclada, Golfo de California, flujos de calor, Mixed layer, Gulf of California, Heat fluxes CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA FÍSICA (VE R 5603 .04)

Determine routes using an algorithm search with information in a simulated environment using player / stage and robot Pioneer

MICHEL GARCIA GARCIA CINHTIA MARIBEL GONZALEZ SEGURA SERGIO ALEJANDRO GONZALEZ SEGURA (2015)

In this paper it implements a depth-first search algorithm performed in the C ++ programming language implemented on the Player / Stage, that allows the use of a robot Pioneer in a simulated environment. The program developed solves a maze that was represented as a binary tree; the results show a solution to the maze with path previously found, the robot travels the map from an initial state, and using its sensors to detect obstacles, the robot take a decision based on the information obtained with his sensors to solve map, same that allows you to reach a destination point.

Article

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS stage Robot Pionner Simulated environment Depth search Maze search

Pattern-based clustering using unsupervised decision trees

ANDRES EDUARDO GUTIERREZ RODRÍGUEZ (2015)

In clustering, providing an explanation of the results is an important task.

Pattern-based clustering algorithms provide, in addition to the list of objects

belonging to each cluster, an explanation of the results in terms of a set of

patterns that describe the objects grouped in each cluster. It makes these

algorithms very attractive from the practical point of view; however, patternbased

clustering algorithms commonly have a high computational cost in the

clustering stage. Moreover, the most recent algorithms proposed within this

approach, extract patterns from numerical datasets by applying an a priori

discretization process, which may cause information loss. In this thesis, we

propose new algorithms for extracting only a subset of patterns useful for

clustering, from a collection of diverse unsupervised decision trees induced

from a dataset. Additionally, we propose a new clustering algorithm based

on these patterns.

Doctoral thesis

Patter mining Pattern-based clustering Clustering Mixed Datasets CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS CIENCIA DE LOS ORDENADORES SISTEMAS DE RECONOCIMIENTO DE CARACTERES