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Sample records for expansion con restricciones

  1. Infactibilidad en programas con restricciones lineales

    Directory of Open Access Journals (Sweden)

    Liern Carrión, V.

    1999-01-01

    Full Text Available En este trabajo resumimos las técnicas más habituales que permiten diagnosticar las causas de infactibilidad de programas con restricciones lineales. Además, presentamos dos métodos que, con las mínimas transformaciones posibles del modelo inicial, permiten hacer viable un programa infactible. Los métodos descritos son aplicados a un modelo de selección de carteras eficientes.

  2. Programación lineal flexible con restricciones difusas

    OpenAIRE

    López Ospina, Héctor Andrés; Restrepo López, Mauricio

    2010-01-01

    El presente trabajo tiene como objetivo presentar los conceptos básicos de la programación lineal flexible o progre-mación lineal con restricciones difusas. Dado que la literatura presenta dicha metodología para restricciones de de-sigualdad, se formula una metodología para restricciones de igualdad y de caja. Se muestra cómo un problema de este tipo equivale a uno de optimización paramétrica. Finalmente, se presentan dos ejemplos ilustrativos en los cua-les se muestra la ventaja de la metodo...

  3. Determinación de restricciones y posibilidades ambientales para la expansion del transporte de gas natural en Colombia

    Directory of Open Access Journals (Sweden)

    Ángel Sanint Enrique

    2011-11-01

    Full Text Available En la línea de la Evaluación Ambiental Estratégica, EAE, se desarrolló un método para la determinación de restricciones y posibilidades ambientales en proyectos de transporte de gas natural por ductos, basado en el uso de herramientas de análisis territorial aplicadas sobre la plataforma SIG (Sistema de Información Geográfica, incorporando criterios ambientales que a escala 1:500.000 apoyarán la toma de decisiones en el nivel de planeación y propiciarán la elaboración del plan de expansión para el transporte de gas natural en Colombia. Para esto, se definió el concepto de ambiente a partir de un Modelo Analítico preexistente; se delimitó un área con posibilidades para la expansión de la red de transporte de gas natural incorporando nuevos trazados; se seleccionaron las variables y factores que complementaban el Modelo Analítico; se definió la estructura de preferencias a partir de una encuesta a expertos; se determinaron las restricciones nacionales y se construyeron superficies numéricas síntesis de critici dad ambiental para cada dimensión. Como resultado, se obtuvieron 5 superficies síntesis, una por cada dimensión, y una superficie final para Colombia, con restricciones y posibilidades ambientales. Además se propusieron análisis complementarios para establecer prioridades en la gestión ambiental.

  4. Manejo de restricciones con funciones de penalidad para la planificación del mantenimiento de locaciones petroleras

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    Jorge Ceferino Valdez

    2014-06-01

    Full Text Available La explotación y transporte de petróleo son actividades muy importantes para el desarrollo económico de la sociedad moderna insdustrial. Sin embargo, estas actividades son generadoras de riesgos que se traducen en contaminaciones que afectan el medio ambiente. Por esta razón, es importante que las empresas petroleras lleven a cabo un correcto mantenimiento de sus locaciones. En casos de planificación de mantenimiento de 100 o más locaciones, PAE es una herramienta que provee un plan de visitas para el mantenimiento, usando un algoritmo evolutivo para producir múltiples soluciones a este problema con restricciones. En este trabajo, se implementa una herramienta de optimización evolutiva aplicando técnicas de manejo de restricciones basadas en funciones de penalidad. Detalles de la implementación, resultados experimentales y beneficios son presentados en este informe.

  5. Epistemic and doxastic logic with restrictions Lógicas epistémica y doxástica con restricciones

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    Manuel Sierra A

    2010-12-01

    Full Text Available Are presented as extensions of classical propositional calculus hierarchies of deductive systems LDR–n and LER–n with n > 1. LER–n is the epistemic logic with restrictions, LDR–n is the doxastic logic with restrictions. The systems LER–1 and LDR–1 are the classical propositional calculus. System LER–(n + 1 can be seen as the result of applying the rule: if X is theorem of LER–n then +X is theorem of LER–(n + 1. Systems also restricts the validity of the axioms +(X → Y → (+X → +Y and +X → X, in terms of depth (complexity with respect to the operator + of X and Y , and also includes restricted versions of the axioms of positive and negative introspection. LER system results from the union of LER–n systems, and can be seen as the S5 modal logic system with different types of restrictions. Changing +X → X by +X →∼+∼X are built LDR–n and the LDR systems. LDR can be seen as the KD45 modal logic system with different types of restrictions. The systems are characterized with a embedded worlds semantics, with which the ‘omniscience logical problem’ is limited.Se presentan como extensiones del cálculo proposicional clásico las jerarquías de sistemas deductivos LER–n y LDR–n, con n ≥ 1. LER–n es la Lógica epistémica con restricciones de profundidad–n, LDR–n es la Lógica doxástica con restricciones de profundidad–n. Los sistemas LER–1 y LDR–1 son el cálculo proposicional clásico. El sistema LER–(n + 1 puede ser visto como el resultado de aplicar la regla: de X se infiere +X, una vez a los teoremas del sistema LER–n, además, se restringe la validez de los axiomas +(X → Y → (+X → +Y y +X → X en términos de la profundidad (complejidad respecto al operador + de X y de Y , y también se incluyen versiones generalizadas y con restricciones de los axiomas de introspección positiva y negativa. El sistema LER resulta de la reunión de los sistemas de la jerarquía, y puede ser visto

  6. Modelo de optimización con restricciones de equilibrio para el control de semáforos

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    Pedreira Andrade, Luís P.

    2006-01-01

    Full Text Available En este trabajo analizamos un problema de control óptimo de semáforos para un cruce de dos carreteras con los dos sentidos de circulación. Exponemos primero, un modelo exacto y acíclico que describe la evolución de las longitudes de las colas como una función del tiempo y de los instantes de cambio (“switching”. Para obtener un modelo simplificado (más manejable para el análisis matemático hacemos algunas hipótesis simplificadoras. Pretendemos calcular una sucesión temporal switching para semáforos que minimiza un criterio, tal como la longitud media de la cola sobre todas las colas, la longitud de la cola en el peor caso, el tiempo medio de espera, etc. Interpretamos las restricciones de nuestro problema como un problema de complementariedad lineal extendido (ELCP, por tanto para determinar la sucesión temporal switching óptima, debemos optimizar la función objetivo en la solución del ELCP, como éste es un problema NP-duro y además como los algoritmos para resolverlo no son factibles cuando el número de ciclos es grande, discutimos varias técnicas para calcular eficientemente subóptimos y aproximar sucesiones temporales switching. También, exponemos un modelo con restricciones de complementariedad y proponemos un método híbrido de solución.

  7. Simulation of the park for electric generation of the Argentine Republic, analysis of its possible expansion with restrictions in the disposability of the fossil fuels; Simulacion del parque de generacion electrica de la Republica Argentina, analisis de su posible expansion con restricciones en la disponibilidad de los combustibles fosiles

    Energy Technology Data Exchange (ETDEWEB)

    Giubergia, J.H.; Coppari, N.R. [Comision Nacional de Energia Atomica, Centro Atomico Constituyentes, Unidad de Actividad Reactores y Centrales Nucleares, Avda. Gral. Paz 1499 (1650) San Martin, Provincia de Buenos Aires (Argentina); Rey, F.C. [Comision Nacional de Energia Atomica, Centro Atomico Ezeiza, Presbitero Juan Gonzalez y Aragon 15, (B1802AYA) Ezeiza, Provincia de Buenos Aires (Argentina)]. E-mail: giuberg@cnea.gov.ar

    2004-07-01

    In this work one simulates, using the program MESSAGE, the generation park electric of the Argentine Republic and their possible expansion, with restrictions in the readiness of fossil fuels. This, as other models of planning energetics promoted by IAEA, optimizes the expansion of the net having as function objective the smallest cost in the system. 25 years they were simulated, adopting like base the anus 2000 and considering different scenarios of internal and external demands. It was analysed the increase of the demand with restrictions in the readiness of the natural gas in the winter periods, since the Argentinean electric system has a great dependence of this fuel. To cover the increase of the electric demand, were selected the machines and fuels, at the moment available, with more technical and economic possibilities. In the scenarios without restrictions to the use of natural gas the program selects to the nuclear power station of Atucha II, to the increase of bench mark of the hydraulic power station of Yacireta and combined cycles that burn natural gas. In those in that the supply of natural gas is limited, it selects previously besides the signal ones, other nuclear power stations, other hydroelectric projects and turbines of gas operating with gas oil to cover the top requirements. (Author)

  8. Problema de Localización y Ruteo con Restricciones de Capacidad: Revisión de la Literatura

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    John Willmer Escobar

    2015-05-01

    Full Text Available En este artículo se hace una revisión exhaustiva del estado del arte de las metodologías de solución existentes para el problema combinado de localización y ruteo con restricciones de capacidad (CLRP. El problema de CLRP tiene una gran cantidad de aplicaciones prácticas en temas relacionados con transporte. Se ha propuesto el siguiente esquema de clasificación de acuerdo al método de solución: (1 Algoritmos Heurísticos Constructivos, (2 Algoritmos Heurísticos Basados en Clústeres, (3 Algoritmos Heurísticos Basados en Trayectoria, (4 Algoritmos Heurísticos Basados en Población, (5 Algoritmos Heurísticos Combinados, (6 Métodos Exactos. Se hace especial énfasis en fortalezas y debilidades de cada metodología publicada, identificando oportunidades de investigación y desarrollo en el área, en el contexto de la aplicación práctica de la problemática.

  9. CONTROL DE INTERVALOS ENTRE BUSES CON INFORMACION EN TIEMPO REAL CONSIDERANDO RESTRICCION DE CAPACIDAD

    OpenAIRE

    DELGADO BREINBAUER, FELIPE ALBERTO

    2011-01-01

    La presente investigación se centra en la formulación de diferentes estrategias de control para un servicio de transporte público. Este servicio opera sobre un corredor unidireccional, compuesto por un conjunto de paradas, semáforos y de buses con características heterogéneas y capacidad limitada de pasajeros. En este sistema, las acciones de control son tomadas al momento de la llegada de un bus a una parada o semáforo, por un controlador central que posee información en tiempo real sobr...

  10. Algoritmos Heurísticos para la Solución del Problema Lineal con Restricciones de Equilibrio (Heuristic Algorithms for Solving Linear Problems with Equilibrium Constraints

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    Dania Tamayo-Vera

    2016-04-01

    Full Text Available Spanish abstract Los problemas lineales con restricciones de equilibrio son un caso particular de los modelos de optimización con restricciones de equilibrio. Debido a la complejidad que presentan, la condición de equilibrio se sustituye por condiciones necesarias obteniéndose un problema con restricciones de complementariedad (MPCC. La estructura del conjunto de soluciones factibles del MPCC obtenido es compleja ya que es la unión de poliedros. Resolver todos los problemas correspondientes a minimizar la función objetivo sobre cada uno de estos poliedros es computacionalmente costoso. El presente trabajo utiliza un enfoque heurístico para dar solución al MPCC, adaptando los algoritmos de Búsqueda Local y Recocido Simulado. Este trabajo presenta un conjunto de funciones de prueba y los resultados computacionales más significativos obtenidos. English abstract Linear equilibrium constrained programming is a special class of optimization models with equilibrium constraints. Because of the complexity of the equilibrium condition it is replaced by necessary conditions, which leads to a complementarity constrained problem (MPCC. The set of feasible solutions in a MPCC is structured as a union of polyhedrons. Solving the MPCC problem would require the minimization of the objective function on each of these polyhedrons. The computation cost of this approach is unfeasible, thus, this work presents a new approach where heuristic algorithms such as Hill Climbing and Simulated Annealing are used to search for good solutions on the polyhedrons space. A new benchmark for linear equilibrium constrained optimization is introduced. The computational results achieved by the proposed heuristics on the new benchmark are presented.

  11. Consistencia interna y validez concurrente del cuestionario para evaluación de limitaciones y restricciones en niños con TDAH

    OpenAIRE

    Salamanca, L.M.

    2014-01-01

    El TDAH es uno de los diagnósticos más frecuentes en psiquiatría infantil, su diagnóstico temprano reviste una gran importancia para su intervención familiar, escolar y social. Basándose en la clasificación internacional del funcionamiento, la discapacidad y la salud CIF, se diseñó un cuestionario para la evaluación de limitaciones en la actividad y restricciones en la participaciónen niños con TDAH, el cuestionario CLARP-TDAH versión padres y profesores. El objetivo de este artículo es deter...

  12. Un algoritmo metaheurístico híbrido para el problema de localización y ruteo con restricciones de capacidad

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    John Willmer Escobar

    2015-01-01

    Full Text Available Este artículo considera el problema de localización y ruteo con restricciones de capacidad (CLRP, en el cual la meta es deter minar los depósitos a ser abiertos, los clie ntes a ser asignados a cada d epósito abierto y las rutas a ser desarrolladas para satisfacer la demanda de los clientes. El objetivo es minimizar la suma de los costos fijos de los depósitos abiertos, el costo del uso de los vehículos, y los costos variables asociados con la dista ncia recorrida por las rutas. E n este artículo, una búsqueda tabú granular (GTS con diferente s estrategias de diversificación contenida en una búsqueda iterativa local (I LS es propuesta para resolver el CLRP. Un procedimiento de per turbación es aplicado cuando la mejor soluc ión encontrada no se puede mej orar por un número determinado de iteraciones. Experimentos computacionales sobre instancias de benchmarking tomadas de la literatura muestran que el alg oritmo propuesto es capaz de obte ner, con tiempos computacionales reducidos, solucione s de alta calidad m ostrando su efectividad.

  13. Métodos computacionales de optimización sin derivadas para minimización con restricciones

    OpenAIRE

    Arouxét, María Belén

    2013-01-01

    La optimización sin derivadas es un área de creciente interés por su potencial relación con aplicaciones en otras disciplinas, dado que es frecuente no contar con una expresión explícita de las funciones involucradas en el problema de optimización sino sólo datos experimentales o simulaciones computacionales. Por lo tanto el objetivo general de este plan es desarrollar nuevos algoritmos eficientes y robustos basados en estrategias adecuadas, analizando su convergencia y validando los mismos m...

  14. Aspectos medioambientales dentro de la planificación forestal con criterios múltiples: Captura de Carbono y restricciones de Adyacencia.

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    León Sánchez, M Amparo

    2008-01-01

    Full Text Available En este trabajo se presenta un modelo de programación por metas no lineal devariable binaria para planificar el aprovechamiento de una plantación productora demadera en Cuba, donde se tienen en cuenta tanto objetivos económicos comoecológicos. Se trata de no superar ciertos niveles de volumen extraído, limitar la edad delos rodales a los que se aplica tala rasa, conseguir un bosque lo más equilibrado posiblerespecto a grupos de edad, superar ciertos niveles del valor actualizado neto en cadaperiodo de la planificación así como un umbral global prefijado de captura de carbonopara toda la planificación. Estos objetivos se tratan de superar teniendo en cuenta,además de restricciones técnicas relativas a los tratamientos, restricciones espaciales deadyacencias que limitan la superficie contigua máxima a la que se aplica tala rasa. Elresultado es un problema sumamente complejo, para el que se ha recurrido al métodometaheurístico basado en Scatter Search SSPMO a la hora de tratar su resolución. Conobjeto de contrastar la potencialidad del modelo propuesto, lo hemos aplicado a unaplantación de Pinus Caribaea situada en la provincia cubana de Pinar del Río.

  15. Solution to the problem of optimum power flows with restrictions of safety by a modified particle optimizer; Solucion del problema de flujos de potencia optimo con restricciones de seguridad por un optimizador de particulas modificado

    Energy Technology Data Exchange (ETDEWEB)

    Onarte Yumbla, Pablo Enrique

    2008-02-15

    de las unidades de generacion para satisfacer la demanda del sistema al minimo costo de produccion, mientras se satisface un conjunto de restricciones operativas de las unidades de generacion y de los sistemas de potencia, a traves del ajuste de las variables de control. Hoy en dia los sistemas de transmision son considerados como una compania independiente, la cual proporciona acceso a todos los participantes. Un esquema de precios debe compensar a las companias de transmision de una manera justa por proveer los servicios de transmision y asignar los costos totales de transmision entre todos los usuarios de la red de transporte. En este trabajo, se emplea un esquema de precios basado en el metodo de rastreo para determinar la contribucion real de los generadores en cada una de las lineas de transmision. Ademas los sistemas de potencia deben ser capaces de resistir la perdida de un componente (ej. lineas, transformadores, generadores), sin poner en peligro el sistema, garantizando su seguridad. Este problema se conoce como flujos de potencia optimo con restricciones de seguridad (FPO-RS). Ademas restricciones como tiempos minimos de encendido y apagado, velocidades de cambio de generacion, perfiles de voltaje y restricciones de estabilidad transitoria son incluidas al problema de FPO-RS. Se propone utilizar un optimizador por enjambre de particulas con operadores de reconstruccion como herramienta de optimizacion para solucionar el problema propuesto. La metodologia propuesta utiliza los operadores de reconstruccion y terminos de penalizacion dinamicos para manejar las restricciones del problema planteado. La utilizacion de los operadores de reconstruccion permite incrementar el numero de particulas (posibles soluciones) que se encuentran dentro de la zona factible de busqueda, lo que reduce el tiempo de computo y mejora la calidad de la solucion encontrada.

  16. Analisis comparativo de una metaheuristica en base a algoritmo genetico vs un metodo de ramificacion y corte para un caso de entrega y recolección con restricciones de ventana de horario

    Directory of Open Access Journals (Sweden)

    Lopez, F.

    2004-07-01

    Full Text Available En la solución de problemas combinatorios, es importante evaluar el costo-beneficio entre la obtención de soluciones de alta calidad en detrimento de los recursos computacionales requeridos. El problema planteado es para el ruteo de un vehículo con entrega y recolección de producto y con restricciones de ventana de horario. En la práctica, dicho problema requiere ser atendido con instancias de gran escala (nodos ≥100. Existe un fuerte porcentaje de ventanas de horario activas (≥90% y con factores de amplitud ≥75%. El problema es NP-hard y por tal motivo la aplicación de un método de solución exacta para resolverlo en la práctica, está limitado por el tiempo requerido para la actividad de ruteo. Se propone un algoritmo genético especializado, el cual ofrece soluciones de buena calidad (% de optimalidad aceptables y en tiempos de ejecución computacional que hacen útil su aplicación en la práctica de la logística. Para comprobar la eficacia de la propuesta algorítmica se desarrolla un diseño experimental el cual hará uso de las soluciones óptimas obtenidas mediante un algoritmo de ramificación y corte sin límite de tiempo. Los resultados son favorables.

  17. UN ALGORITMO METAHEURÍSTICO BASADO EN RECOCIDO SIMULADO CON ESPACIO DE BÚSQUEDA GRANULAR PARA EL PROBLEMA DE LOCALIZACIÓN Y RUTEO CON RESTRICCIONES DE CAPACIDAD A META-HEURISTIC ALGORITHM BASED ON THE SIMULATED ANNEALING WITH GRANULAR SEARCH SPACE FOR THE CAPACITATED LOCATION ROUTING PROBLEM

    Directory of Open Access Journals (Sweden)

    John Willmer Escobar

    2012-12-01

    Full Text Available Consideramos el problema de localización y ruteo con restricciones de capacidad (CLRP, en el cual la meta es determinar los depósitos a ser abiertos, los clientes a ser asignados a cada depósito abierto, y las rutas a ser construidas para satisfacer las demandas de los clientes. El objetivo es minimizar la suma de los costos de abrir depósitos, de los costos de los vehículos usados, y de los costos variables asociados con la distancia recorrida por las rutas. En este paper, proponemos una metaheurística basada en simulado y recocido con espacio de búsqueda granular para resolver el problema CLRP. Experimentos computacionales en instancias de benchmarking tomadas de la literatura muestran que el algoritmo propuesto es capaz de obtener, dentro de tiempos computacionales razonables, soluciones de alta calidad mostrando su eficacia.The article deals with the Capacitated Location Routing Problem (CLRP where the goal is to determine the depots to be opened, the customers to be assigned to each deposit opened, and the routes to be constructed for fulfilling customers' demands. The objective is to minimize the sum of costs resulting from opening depots, costs resulting from used vehicles, and variable costs associated to the distance across the routes. In this paper, a metaheuristic based on simulated annealing with granular search space for solving the CLRP is proposed. Computational experiments on benchmarking instances taken from literature show that the proposed algorithm is able to obtain high-quality solutions within reasonable computational times, thus showing its efficiency.

  18. Expansion ortopedica maxilar con ortodoncia osteogenica periodontalmente acelerada

    National Research Council Canada - National Science Library

    Lopez Buitrago, Diego Fernando; Jaramillo Abadia, Isabel Cristina

    2014-01-01

    .... Historicamente, el tratamiento de la discrepancia esqueletica transversal ha estado acompanado de procedimientos de cirugia ortognatica que separan las suturas para permitir la expansion mediante...

  19. Estrategias evolutivas como una opción para la optimización de funciones no lineales con restricciones Evolution strategies as an option for optimizing non linear functions with restrictions

    Directory of Open Access Journals (Sweden)

    Diana M. Ortiz

    2011-01-01

    Full Text Available Estrategias de evolución es una técnica bio-inspirada, eficiente y robusta para resolver problemas de optimización donde el espacio de soluciones es no restringido. Sin embargo, esta suposición es irreal en muchos casos porque el espacio de soluciones es limitado por fronteras complejas en la forma de restricciones tanto lineales como no lineales. En este artículo de investigación, se propone una modificación al algoritmo original de estrategias de evolución para optimizar problemas donde el espacio de soluciones es limitado usando restricciones complejas. El método propuesto es basado en el uso de una función de penalización la cual es cero dentro de la región factible, e igual al máximo valor dentro de la región factible cuando se considera un punto que es no factible. La aproximación propuesta es probada usando seis problemas de prueba bien conocidos. En todos los casos, esta aproximación encontró un punto óptimo igual o menor que los valores reportados en la literatura.Evolution Strategies is a bio-inspired, robust, and efficient technique for solving optimization problems where the solution space is unrestricted. However, this assumption is unreal in many cases because the solution space is limited by complex boundaries in the form of linear and non-linear restrictions. In this paper, a modification of the original algorithm of Evolution Strategies for optimizing problems where the solution space is bounded using complex restrictions is proposed. The proposed method is based on the use of a penalization function which is zero inside of the feasible region and equal to the maximum value inside of the feasible region when an unfeasible point is considered. The proposed approach is proved using six benchmark problems. In all cases, our approach found an optimal point equal or lower than the values reported in the literature.

  20. Short run hydrothermal coordination with network constraints using an interior point method Coordinación hidrotérmica de corto plazo con restricciones de red usando un método de punto interior

    Directory of Open Access Journals (Sweden)

    Jesús María López Lezama

    2008-12-01

    Full Text Available This paper presents a lineal optimization model to solve the hydrothermal coordination problem. The main contribution of this work is the inclusion of the network constraints to the hydrothermal coordination problem and its solution using an interior point method. The proposed model allows working with a system that can be completely hydraulic, thermal or mixed. Results are presented on the IEEE 14 bus test system.En este artículo se presenta un modelo de optimización lineal para resolver el problema de la coordinación hidrotérmica. El principal aporte de este trabajo es la inclusión de las restricciones de red al problema de coordinación hidrotérmica y su solución usando un método de punto interior. El modelo propuesto permite manejar un sistema completamente hídrico, completamente térmico o un sistema mixto. Se presentan resultados para el sistema de prueba IEEE de 14 barras.

  1. Modelado de materiales compuestos por elementos finitos usando restricciones cinematicas

    National Research Council Canada - National Science Library

    Barschke, Merlin; Uribe, David; Ruiz, Oscar E; Jensen, Jens; Lopez, Carlos

    2009-01-01

    El proposito de este articulo es presentar simulaciones del comportamiento de materiales compuestos basado en restricciones cinematicas entre las mismas fibras y entre las fibras y la resina circundante...

  2. LA INCIDENCIA DE LOS ENTORNOS REGIONALES SOBRE LAS RESTRICCIONES FINANCIERAS EN PEQUEÑAS Y MEDIANAS EMPRESAS

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    Mariluz Maté Sánchez-Val

    2016-01-01

    Full Text Available El principal objetivo de este artículo es estudiar la heterogeneidad regional en las restricciones financieras sufridas por la pequeña y mediana empresas (pyme. Para ello, se desarrolló una aplicación empírica con una muestra de pyme españolas, proponiendo un modelo de acceso financiero y diferenciando entre dos regiones. Las estimaciones se realizan mediante modelos probit dinámicos con datos de panel. Los resultados confirman la importancia de incluir esa diferenciación regional. En concreto, se encontró que en la región menos desarrollada, las características específicas de las empresas de reducido tamaño no son tan importantes para determinar la probabilidad de tener restricciones financieras como las propias condiciones regionales donde la empresa tenga su sede.

  3. Teoría de restricciones para procesos de manufactura

    National Research Council Canada - National Science Library

    Gabriela Villagómez; Jorge Viteri Moya; Alberto Medina

    2012-01-01

    ... específicamente la producción de snacks de papas fritas utilizando la Teoría de Restricciones (TOC) como metodología científica. Se realizó la medición de capacidad de cada una de las operaciones que componen el proceso de...

  4. Teoría de restricciones para procesos de manufactura

    Directory of Open Access Journals (Sweden)

    Gabriela Villagómez

    2012-06-01

    Full Text Available La empresa “Productos Alexander” fabricante de snacks de la ciudad de Quito, tiene un sistema de producción que no permite el abastecimiento de los pedidos de sus clientes reflejando un índice de servicio al cliente de 89,58% ya que sus procesos están trabajando con capacidades que no se encuentran correctamente programadas, en vista de tal razón el objetivo de esta investigación es proponer un sistema de mejora continua con el fin de aumentar y efectivizar específicamente la producción de snacks de papas fritas utilizando la Teoría de Restricciones (TOC como metodología científica. Se realizó la medición de capacidad de cada una de las operaciones que componen el proceso de elaboración de snacks y se identificó la restricción en el proceso de fritura, que no estaba trabajando el 100% del tiempo en la jornada diaria limitando así la capacidad de la fábrica, por lo que se optó por explotar la restricción para eliminarla. La propuesta planteada para explotar la restricción consiste en una mejor programación de la producción, reducción de lote de transferencia de proceso a proceso, programación de la cantidad de trabajo para cada uno de los operarios en la jornada, la preparación del proceso y la fijación de turnos en la hora de almuerzo de los operarios lo que contribuye a agilizar el proceso de fritura y permitir que trabaje a su máxima capacidad el 100% del tiempo.Dicha propuesta se puede considerar como una solución al problema y así mejorar los niveles de producción de la empresa, tomando en cuenta que en base a los indicadores de TOC el Beneficio Neto de la empresa aumentaría de $15 333.09 a $ 17 392.14 al cumplir en cantidad y a tiempo todos los pedidos de los clientes.Abstract:The company "Products Alexander" snack manufacturer in the city of Quito, has a production system that cannot supply customer orders, with a customer service index of 89,58%, also their processes are working with capabilities that

  5. Restricciones cambiarias y el boom del fideicomiso inmobiliario

    OpenAIRE

    Olthoff, Bárbara

    2015-01-01

    TEMA: Impacto de las modificaciones del mercado cambiario en los fideicomisos de construcción. PROBLEMA: ¿Cual fue el impacto y las posteriores consecuencias de las modificaciones del mercado cambiario a raíz de las restricciones a la compra de moneda extranjera impuesta por la Comunicación A 5239 del Banco Central de la República Argentina y siguientes, en los fideicomisos de construcción en la ciudad de Mar del Plata? ¿Qué medidas se llevaron a cabo para adaptar la figura jurídica del...

  6. Planning the expansion of transmission with evolutionary programming; Planeacion de la expansion de transmision con programacion evolutiva

    Energy Technology Data Exchange (ETDEWEB)

    Ceciliano Meza, Jose Luis; Nieva Gomez, Rolando [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    1999-07-01

    A method of evolutionary programming for the planning of transmission networks in electrical power systems is presented. This is a whole problem mixed and nonlinear, with a combinatory nature that leads to a very large number of possible solutions for electrical systems of medium and large scale. The problem of transmission planning is described briefly and later it is formulated in mathematical terms. The proposed algorithm of evolutionary programming is applied to a large scale network that is representative of the Mexican electrical system. [Spanish] Se presenta un metodo de programacion evolutiva para la planeacion de redes de transmision en sistemas electricos de potencia. Este es un problema entero mixto y no lineal, con una naturaleza combinatoria que conduce a un numero muy grande de soluciones posibles para sistemas electricos de mediana y gran escala. Se describe brevemente el problema de planeacion de transmision y posteriormente se formula en terminos matematicos. El algoritmo propuesto de programacion evolutiva se aplica a una red electrica de gran escala que es representativa del sistema electrico Mexicano.

  7. Planning the expansion of electrical transmission networks with evolutionary programming; Planeacion de la expansion de redes de transmision electrica con programacion evolucionaria

    Energy Technology Data Exchange (ETDEWEB)

    Ceciliano Meza, Jose Luis

    1997-12-31

    In this work it is presented for the first time in the literature the solution of the problem of the planning the expansion of an electrical transmission network (PERTE) with the use of the Evolutionary Programming. The evolutionary programming is a stochastic method of optimization with similar characteristics to the generic algorithms, but different. During the development of this work it is shown what each one of these two heuristic methods of optimization consist of. Additionally, the main characteristics of other two heuristic methods known in the literature are described (Tabu Searching and Simulated Annealing). These two methods together with the genetic algorithms and decomposition of Benders have also been used to solve the problem of planning PERTE. The operation of the proposed algorithm of evolutionary programming was tested in two networks of electrical transmission. The first case of test is a system which is known in the literature. The second case is a representative system of the electrical transmission network of Central America. The results obtained improve all the results shown when applying different heuristic methods of optimization (genetic algorithms, simulated annealing and Tabu searching) to solve the same problem. [Espanol] En este trabajo se presenta por primera vez en la literatura, la solucion del problema de la planeacion de expansion de una red de transmision electrica (PERTE) con el uso de la Programacion Evolucionaria. La programacion evolucionaria es un metodo estocastico de optimizacion con caracteristicas similares a los algoritmos geneticos, pero diferente. Durante el desarrollo de este trabajo se muestra en que consiste cada uno de estos dos metodos heuristicos de optimizacion. Ademas, se describen las caracteristicas principales de otros dos metodos heuristicos conocidos en la literatura (busqueda Tabu y Recorrido Simulado). Estos dos metodos juntos con los algoritmos geneticos y descomposicion de Benders tambien han sido

  8. Detección de restricciones en la producción de agave azul (Agave tequilana Weber var. azul) mediante percepción remota

    OpenAIRE

    Ramón Ceja Ramírez; Diego Raymundo González Eguiarte; José Ariel Ruiz Corral; Luis Alberto Rendón Salcido; José Germán Flores Garnica

    2017-01-01

    El agave azul (Agave tequilana Weber, var. azul) se utiliza, principalmente, para la producción del Tequila; una bebida espirituosa. El estado de Jalisco, México, contribuye con el 90% de la producción; esto constituye un importante apoyo a la economía del Estado. El objetivo de la presente investigación fue determinar la superficie ocupada por agave azul, que presentó restricciones en su producción en la región Valles, correspondiente a los municipios de Tequila, Amatitán y El Arenal, en el ...

  9. Una formulación matemática y de solución para programar cirugías con restricciones de recursos humanos en el hospital público A mathematical formulation and solution to schedule surgeries with human resource constraints in a public hospital

    Directory of Open Access Journals (Sweden)

    Lorena Pradenas Rojas

    2012-08-01

    Full Text Available Actualmente, los hospitales públicos nacionales e internacionales presentan demandas que sobrepasan la capacidad de atención, lo que ha provocado un creciente interés por usar herramientas de gestión en los centros clínicos que les permita realizar de forma eficiente y eficaz la entrega de servicios a los distintos pacientes. El presente estudio aporta una nueva forma de abordar el problema de programación de cirugías, desde la programación matemática, presentando un modelo de optimización multiobjetivo y un algoritmo metaheurístico implementado computacionalmente, que permite la programación semanal de intervenciones quirúrgicas, cumpliendo con los requerimientos de pabellones y personal especializado necesario para su realización. Se utiliza una instancia de prueba, donde el tiempo de ejecución del algoritmo, implementado en C++, fue de siete minutos para 191 cirugías en lista de espera. El tiempo alcanzado es considerablemente menor a la programación realizada con un sistema manual, como los actualmente usados en hospitales públicos.Currently, national and international public hospitals have demands that exceed their service capacity, which has caused a growing interest in management sciences to deliver these medical centers the tools that will enable them to perform efficiently and effectively, delivering services to different patients. This study provides a new way of approaching the problem of surgical scheduling using mathematical programming, presenting a multi-objective optimization model and a metaheuristic algorithm implemented computationall. The solution allows weekly schedule of surgical procedure and complying with the requirements of the flag and expertise necessary for realization. We ordered test instances where the execution time of the algorithm, coded in C++, was 7 minutes for a 191 surgeries waiting list, which is a considerable less amount of time to this schedule than using a manual approach. The latest

  10. Detección de restricciones en la producción de agave azul (Agave tequilana Weber var. azul mediante percepción remota

    Directory of Open Access Journals (Sweden)

    Ramón Ceja Ramírez

    2017-07-01

    Full Text Available El agave azul (Agave tequilana Weber, var. azul se utiliza, principalmente, para la producción del Tequila; una bebida espirituosa. El estado de Jalisco, México, contribuye con el 90% de la producción; esto constituye un importante apoyo a la economía del Estado. El objetivo de la presente investigación fue determinar la superficie ocupada por agave azul, que presentó restricciones en su producción en la región Valles, correspondiente a los municipios de Tequila, Amatitán y El Arenal, en el estado de Jalisco, México, por medio de percepción remota. Se utilizó una imagen adquirida por el satélite LANDSAT 5 el 2 de abril de 2011, la cual se procesó para su calibración radiométrica, corrección atmosférica y georreferenciación. La interpretación digital se hizo a través del proceso de clasificación supervisada utilizando la opción de máxima probabilidad. Los campos de entrenamiento se seleccionaron de información de campo y de la base de datos del Consejo Regulador del Tequila (CRT. Los resultados se plasmaron en mapas temáticos; distribución de agave y no agave y distribución de agave con restricciones. El 45% del área ocupada por el cultivo presentó restricciones relacionadas con: aspectos económicos (restricción tipo 1, plagas y enfermedades (restricción tipo 2 y efectos por exceso de humedad del suelo (restricción tipo 3. Para evaluar la precisión de estos datos se aplicó una matriz de error que reportó una precisión general del 73%. Este valor es aceptable considerando la resolución a 30 m del sensor (LANDSAT 5 y la peculiaridad del cultivo. El uso de imágenes LANDSAT por su resolución espectral y radiométrica es aceptable para el estudio del cultivo del agave azul según lo observado en campo y lo expresado por el procesamiento de la imagen.

  11. Expansión posterior con resortes y avance fronto-orbitario simultáneo en craneosinostosis sindrómicas Spring-assisted posterior expansion and simultaneous fronto-orbitary expansion in syndromic cranyosinostosis

    Directory of Open Access Journals (Sweden)

    J.C. Rodríguez

    2011-12-01

    Full Text Available Las craneoestenosis sindrómicas son anomalías congénitas de difícil resolución y requieren generalmente varios procedimientos quirúrgicos. La expansión posterior de la calota permite disminuir la hipertensión endocraneana y sus efectos sobre el cerebro. La utilización de resortes para la expansión posterior ha demostrado ser un método efectivo y estable, disminuyendo la morbilidad de los procedimientos tradicionales. La combinación de la expansión posterior con resortes y el avance frontoorbitario en una sola etapa, antes del año de vida, disminuye el número de intervenciones necesarias obteniéndose una buena remodelación de la bóveda craneana. Presentamos nuestra experiencia en 3 casos de craneoestenosis sindrómica mediante la realización simultánea de ambos procedimientos con buenos resultados estéticos y funcionales.Syndromic craniosynostosis is a difficult-to-resolve congenital anomaly generally requiring several surgical procedures. Expansion of the posterior cranial vault diminishes intracranial hypertension and its deleterious effect on the brain. The use of spring-assisted distraction for posterior vault expansion showed to be an effective and stable method with lower morbidity than that seen in traditional procedures. The combination of spring-assisted posterior vault expansion and fronto-orbital advancement in a single stage before one year of life decreases the number of surgical interventions necessary and leads to adequate remodeling of the cranial vault. Here we present 3 cases of syndromic craniosynostosis who simultaneously underwent both procedures with good esthetic and functional results.

  12. Planning model for the expansion of the electrical generation system with risk demarcation criteria; Modelo para la planificacion de la expansion del sistema electrico de generacion con criterios de acotamiento de riesgo

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Galicia, Julio Alberto; Nieva Gomez, Rolando [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2009-07-01

    The general characteristics of a planning model for the electrical generation system expansion with risk demarcation criteria, as well as the main results of a representative study case of the Mexican Electrical System is presented. The model is based on a methodology of multiannual optimization for the generation expansion plans determination. In this context, every expansion plan defines the technology type to be installed, as well as the installation year, unit size and its location within a regional electric network. For this purpose, the model considers an interregional representation of the system identifying the necessary reinforcements to the capacity of the interregional connections. It also incorporates a Demarcation of Risk module that considers the uncertainty of the future scenarios of fuels prices to generate a set of expansion plans, among which includes the following: a) For every future of the fuel prices: the plan that diminishes the present value of the total cost (investment plus production). b) The plan that diminishes the economic risk derived from the uncertainty in the future of the fuel prices. c) A subgroup of expansion plans that are located in the efficient borders of decision, under the context of three criteria of interest: the economic risk, the investment cost of and the total cost in the future considered of greater relevance. [Spanish] Se presentan las caracteristicas generales de un modelo de planificacion de la expansion del sistema electrico de generacion con criterios de acotamiento de riesgo, asi como los principales resultados de un caso de estudio representativo del Sistema Electrico Mexicano. El modelo se basa en una metodologia de optimacion multi-anual para la determinacion de planes de expansion de la generacion. En este contexto, cada plan de expansion define el tipo de tecnologia que debera instalarse, asi como el ano de instalacion, el tamano de la unidad y su localizacion dentro de una red electrica regional. Para

  13. Percepción de inseguridad, victimización y restricciones en la vida cotidiana en función del ciclo vital, en Morelos, México

    OpenAIRE

    Vera Jiménez, Alejandro; Ávila Guerrero, María Elena; Musitu Ochoa, Gonzalo; Martinez-Ferrer, Belen; Musitu Ochoa, Gonzalo; Montero Montero, David

    2017-01-01

    Palabras claves: fuente, Tesauro de política criminal latinoamericana - ILANUD Los estudios sobre percepción de inseguridad, victimización y restricciones en la vida cotidiana en países con altos índices de criminalidad son escasos. Objetivo: examinar la percepción de inseguridad, victimización y variaciones de las rutinas en función de la edad. Método: se ha realizado una adaptación de la Encuesta Nacional sobre Victimización y Percepción de Inseguridad (ENVIPE). Partici...

  14. Estímulos y restricciones para la investigación en administración en Colombia

    Directory of Open Access Journals (Sweden)

    Liliana María Gutiérrez Vargas

    2013-09-01

    Full Text Available Este artículo presenta los estímulos y restricciones que tiene la investigación en administración en Colombia, partiendo de las consideraciones generales del país, como la política de Ciencia y Tecnología, las consideraciones de calidad que impone el Ministerio de Educación Nacional a los programas curriculares y las condiciones propias que hacia el fortalecimiento de la investigación ofrecen las universidades y las facultades de administración en el país. El trabajo empírico se desarrolló con investigadores y decanos de las facultades, mediante una encuesta online en la que participaron 194 investigadores (tasa de respuesta de 30,6% y 63 decanos o directores de programas (tasa de respuesta del 27,7%; adicionalmente, se seleccionó una muestra intencional de 25 investigadores y 11 decanos para realizar entrevistas a profundidad, y se realizaron tres grupos focales. Los principales hallazgos en referencia se evidencian en: recursos para investigar, estímulos económicos para los investigadores, la política de ciencia y tecnología, la comunidad científica, las formas de divulgación de los resultados investigativos y los aspectos administrativos; puntos estos que vienen siendo analizados como políticas institucionales por las universidades para fomentar la investigación. Sin duda, los esfuerzos que se focalicen para minimizar los restrictores potencian el desarrollo de esta incipiente comunidad académica.

  15. Allocation of the transmission service cost with base in marginal costs of the transmission network expansion; Asignacion del costo del servicio de transmision con base en costos marginales de expansion de la red de transmision

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Casillas, Manuel E.; Nieva Gomez, Rolando [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2001-07-01

    The transmission charges to the users must be completely defined in those systems where the restructuring has broken up the traditional functions of the companies; in order to introduce competition in the generation and commercialization segments of the electrical energy. The fundamentals of a method used are explained to assure the transmission service cases between their users. The method is based on the marginal expansion costs of the transmission network. Their more known applications have been in competitive markets of energy, in particular, where the energy price is the same one in all the localities. Nevertheless, it can be used under other forms of organization of the electrical industry. In order to illustrate results, the obtained ones from their application to the most important part of the transmission network of the Mexican system that operates interconnected, are presented. [Spanish] Los cargos de transmision a los usuarios deben estar completamente definidos en aquellos sistemas donde la reestructuracion ha desagregado las funciones tradicionales de las empresas; para introducir competencia en los segmentos de generacion y comercializacion de la energia electrica. Se explican los fundamentos de un metodo utilizado para asegurar los casos del servicio de transmision entre sus usuarios. El metodo se basa en los costos marginales de expansion de la red de transmision. Sus aplicaciones mas conocidas han sido en mercados competitivos de energia, en particular, donde el precio de la energia es el mismo en todas las localidades. Sin embargo, puede utilizarse bajo otras formas de organizacion de la industria electrica. Con el proposito de ilustrar resultados, se muestran los obtenidos de su aplicacion a la parte mas importante de la red de transmision del sistema mexicano que opera interconectada.

  16. RESTRICCIONES AL DOMINIO, RELACIONES DE VECINDAD E INMISIONES INMATERIALES: UN RECORRIDO DESDE EL DERECHO ROMANO

    Directory of Open Access Journals (Sweden)

    Jonathan Matías Brodsky

    2015-09-01

    Full Text Available Si bien el dominio siempre ha sido concebido como el más amplio derecho que una persona puede tener sobre una cosa, también es cierto que ha reconocido limitaciones de distinta índole. El propósito de este ensayo es analizar el origen de estas restricciones en el Derecho Romano –y particularmente aquella vinculada a las inmisiones inmateriales en las relaciones de vecindad– así como estudiar la proyección de tales nociones romanas en el Derecho decimonónico francés, el Código Civil argentino y su Proyecto de Reforma del año 2012.

  17. DESARROLLO DE UNA METODOLOGÍA DE IMPLEMENTACIÓN DE LOS CONCEPTOS DE TOC (TEORÍA DE RESTRICCIONES, PARA EMPRESAS COLOMBIANAS

    Directory of Open Access Journals (Sweden)

    José Arturo Gonzáles Gómez

    2003-01-01

    Full Text Available La Teoría de Restricciones (TOC es un sistema de pensamiento gerencial que ha sido aplicado con éxito en multitud de empresas en el mundo. Sin embargo, no existe una documentación adecuada de su implementación en Pequeñas y Medianas Empresas (PyMEs en Colombia, por lo que no hay un protocolo de implementación que guíe al empresario en dicho proceso. Al realizar una investigación documental, unida con un diagnóstico y aplicación piloto en dos pequeñas empresas del sector de manufactura de productos plásticos, se estructuró una propuesta que parte desde conocer el estado actual de la empresa, satisfacer algunos requerimientos previos a la implementación de técnicas de TOC y la implementación propiamente dicha de las mismas. Como conclusión se encontró que antes de emprender cualquier proceso de mejoramiento es necesario “ordenar la casa”: Lograr una claridad en los aspectos administrativos, productivos y de calidad básicos, para así garantizar la efectividad y sostenibilidad de cualquier avance que se alcance.

  18. Modelado de Materiales Compuestos por Elementos Finitos usando Restricciones Cinemáticas Finite Element Modeling of Composite Materials using Kinematic Constraints

    Directory of Open Access Journals (Sweden)

    Oscar E. Ruiz

    2009-12-01

    Full Text Available El propósito de este artículo es presentar simulaciones del comportamiento de materiales compuestos basado en restricciones cinemáticas entre las mismas fibras y entre las fibras y la resina circundante. En la revisión de literatura, los autores han encontrado que las restricciones cinemáticas no han sido plenamente explotadas para modelar materiales compuestos, probablemente debido a su alto costo computacional. El propósito de este articulo es exponer la implementación y resultados de tal modelo, usando Análisis por Elementos Finitos de restricciones geométricas prescritas a los nodos de la resina y las fibras. Las descripciones analíticas del comportamiento de materiales compuestos raramente aparecen. Muchas aproximaciones para describir materiales compuestos en capas son basadas en la teoría de funciones C1Z y C0 Z, tal como la Teoría Clásica de Capas (CLT. Estas teorías de funciones contienen significativas simplificaciones del material, especialmente para compuestos tejidos. Una aproximación hibrida para modelar materiales compuestos con Elementos Finitos (FEA fue desarrollada por Sidhu y Averill y adaptada por Li y Sherwood para materiales compuestos tejidos con polipropileno de vidrio.The purpose of this article is to present simulations of the behavior of composite materials based on kinematic restrictions among the fibers themselves and among fibers and the surrounding resine. In the literature review the authors have found that the kinematic restrictions have not been fully exploited for modeling composite materials, probably due to their high computational expense. The purpose of this article is to show the implementation and results of such a model, by using a Finite Element Analysis of geometric restrictions prescribed to the resine and fiber nodes. Closed analytic descriptions on behavior of layered composite materials are very rare. Many approaches to describe layered composite material are based on the theory of

  19. SELECCIÓN DE PORTAFOLIOS DE INVERSIÓN SOCIALMENTE RESPONSABLES USANDO EL MÉTODO DE LAS RESTRICCIONES Y LA TÉCNICA MULTICRITERIO PROCESO ANALÍTICO JERÁRQUICO

    Directory of Open Access Journals (Sweden)

    Lady Mayerly Bernard Suárez

    Full Text Available En este artículo se presenta un procedimiento que permite apoyar el proceso de decisión de los inversionistas al seleccionar un portafolio que cumpla con sus expectativas económicas y con aquellas relacionadas con Responsabilidad Social Empresarial (RSE. Para ello, se consideran criterios de rentabilidad y riesgo como medidas económicas que, abordadas desde el método de las restricciones, dan como resultado una serie de portafolios eficientes que se emplean como alternativas para la aplicación de la técnica multicriterio AHP (sigla en inglés, la cual permite establecer el portafolio que cumple con criterios de gobierno corporativo, relaciones con colaboradores, medio ambiente y relaciones con la comunidad como medidas de RSE. El procedimiento se aplica en la selección de portafolios de inversión para acciones del mercado bursátil colombiano, dando como resultado que el portafolio que mejor cumple con los criterios establecidos en este artículo para RSE también es el de mínimo riesgo.

  20. Nacidos para la adopción: hijos de personas con discapacidad intelectual y mental

    OpenAIRE

    Seda, Juan Antonio

    2014-01-01

    Existe una brecha entre las declaraciones y normas sobre las personas con discapacidad y el efectivo respeto de sus derechos. Esta incongruencia entre discursos públicos y prácticas sociales reales puede verse reflejada, entre otras situaciones, en las restricciones en el ejercicio de la paternidad, la maternidad y la sexualidad plena, en personas con discapacidad intelectual o mental. La Convención sobre los Derechos de las Personas con Discapacidad promueve el respeto por el matrimonio, la ...

  1. Maxillary Expansion

    OpenAIRE

    Agarwal, Anirudh; Mathur, Rinku

    2010-01-01

    ABSTRACT Maxillary transverse discrepancy usually requires expansion of the palate by a combination of orthopedic and orthodontic tooth movements. Three expansion treatment modalities are used today: rapid maxillary expansion, slow maxillary expansion and surgically assisted maxillary expansion.This article aims to review the maxillary expansion by all the three modalities and a brief on commonly used appliances.

  2. Restricciones conceptuales del ordenamiento territorial colombiano; usos del territorio y formas de propiedad

    Directory of Open Access Journals (Sweden)

    Catalina Trujillo-Osorio

    2015-01-01

    Full Text Available El presente trabajo analiza los efectos que las diversas formas de propiedad generan sobre el ordenamiento territorial del país. El estudio se desarrolla a partir de la revisión de fuentes documentales académicas, información estadística y la normatividad relacionada. Los resultados se estructuran en tres secciones: la primera sobre conceptos y definiciones en torno a las formas de propiedad; la segunda describe las características de cada tipo de propiedad, y la tercera analiza las relaciones entre formas de propiedad, ordenación del territorio y desa - rrollo regional. Dentro de los resultados se resalta la transformación dinámica de los conceptos de propiedad asociados al suelo, la tierra, y el territorio. También se identifican diversas restricciones que las formas de propiedad ocasionan en la gestión del territorio, especialmente la propiedad sobre el subsuelo, que aparece como el elemento más restrictivo en la planificación territorial; también se resaltan el traslape múltiple de formas de propiedad y la ausencia de información estadística actualizada sobre estos temas.De los resultados se desprende la necesidad de profundizar en las implicaciones del dominio estatal sobre el subsuelo, en la planificación y ordenación del territorio. La importancia del saneamiento y la definición de límites de cada tipo de propiedad por parte de los respectivos entes administrativos y la pertinencia del acceso a la información estadística y espacial, desde la cual se pueda reconocer la realidad territorial del país.

  3. Manejo de restricciones con algoritmos evolutivos aplicados al problema de optimización de corte y empaquetado

    Directory of Open Access Journals (Sweden)

    Eduardo Alberto Burgos Portarreiu

    2014-06-01

    Full Text Available Se considera el problema de encontrar un patrón de empaquetamiento de rectángulos de distintos tamaños, dentro de un rectángulo de mayor tamaño cuyo objetivo consiste en que el área desperdiciada sea mínima. El problema de corte de piezas rectangulares pertenece a la familia de problemas de corte y empaque y sus aplicaciones se pueden observar en industrias de perfiles metálicos, corte de maderas, papel, plástico o vidrio en donde los componentes rectangulares tienen que ser cortados desde grandes hojas de material realizando cortes perpendiculares a los ejes horizontales y verticales. Este problema de empaquetamiento y corte es de interés académico y científico ya que sirve como base para problemas de mayor complejidad.

  4. Anonimización de citas médicas mediante programación con restricciones

    OpenAIRE

    Cabana Ramírez, Richard Jordan

    2016-01-01

    El actual auge de internet y las comunicaciones genera inmensas cantidades de información. De entre toda esta información tiene especial interés aquella que es personal y privada, ya que puede comprometer la seguridad o intimidad de las personas. La información médica de una persona es una de las más vulnerables y es de vital importancia proteger la identidad de los pacientes, así como los resultados y diagnósticos a los que se someten. Este trabajo se centra en intentar dificultar la identif...

  5. Herramienta para la enseñanza de la Teoría de las Restricciones para la Toma de Decisiones Empresariales

    OpenAIRE

    Pessacq, Raúl Adolfo; Champredonde, Raúl; Sanz, Cecilia Verónica

    1997-01-01

    Se desarrolló un software educativo de nivel universitario, tomando como base la Teoría de Restricciones para la toma de decisiones empresariales. Se realiza conjuntamente una crítica a la Contabilidad de Costos, utilizando conceptos del libro de E. Goldratt: “El Síndrome de Pajar”. El tema pertenece a uno de los nuevos movimientos de gerenciamiento y propone el estudio sistémico de un proceso productivo, optimizando el todo a partir de la detección y explotación de restricciones. Contrapone ...

  6. Rasgos de personalidad, edad, cultura y restricciones hidricas y dieteticas en pacientes en hemodialisis

    National Research Council Canada - National Science Library

    Ruiz Vaca, Ana Maria; Munoz Garcia, Victoria Eugenia; Garcia Vega, Jose Luis; Mohamed Maanan, Nayet; Garcia Criado, Juana; Bagdad Abselam, Aziza

    2011-01-01

    .... Pensamos que los rasgos de la personalidad, la edad, la cultura, pueden influir en la aceptacion de la enfermedad de nuestros pacientes renales en tratamiento sustitutivo con hemodialisis, y por lo...

  7. Restricciones en el canal de comunicación y representación de influencia en situación de toma de decisión Restrictions in the communication channel and influence representation in taking up decisions

    Directory of Open Access Journals (Sweden)

    Jorge R. Vivas

    2001-06-01

    Full Text Available La comunicación mediada por computadora ha tenido un efecto de alto impacto social en la última década. Los efectos psicosociales de la utilización de estos medios tecnológicos en la comunicación humana son observados con creciente interés. Este trabajo reporta las variaciones de la percepción de influencia durante una tarea de toma de decisión colaborativa al modificar las restricciones del canal de comunicación (presencial o mediado por computadora. Se trabajó con cien sujetos repartidos en ambas condiciones de tarea sobre un problema de decisión múltiple. Los análisis muestran una diferencia notable en los aspectos considerados por los individuos para la construcción de la representación de influencia en una y otra modalidad. Estas diferencias son interpretadas como producto de que la magnitud de la presencia social esta modulada por las restricciones inherentes al canal mediador, dificultando y hasta impidiendo, la percepción de los mecanismos de influencia social que permiten la construcción de una representación de influencia ajustada a los efectivos intercambios realizados en torno al producto generado colaborativamente.Computer mediated communication had a high social impact in the last decade. The psychosocial effects of the use of these technological media on human communication are observed with growing interest. This work reports the differences of influence perception during the collaborative making decision task when varying the communicational channel restrictions (Face To Face or computer mediated. The design included a hundred students in both task conditions on a multiple decision problem. The outcomes show a great differences in how individuals remarks different aspects for the representational construction of the influence in each modality. These results suggest that the amount of social presence is modulated by the channel restrictions, which make it difficult and even constrain, the perception of the

  8. RESTRICCIONES NO ARANCELARIAS AL COMERCIO CHILENO: PRINCIPALES OBSTÁCULOS PARA LOS EXPORTADORES COLOMBIANOS

    Directory of Open Access Journals (Sweden)

    Ana María Barajas Ramírez

    2017-07-01

    Full Text Available La naturaleza cambiante del comercio internacional conlleva a que los países protejan tanto su industria nacional como sectores importantes de su economía con el fin de garantizar la producción doméstica , por tanto no sorprende encontrar como la economía chilena aparentemente la más exitosa de América latina elabora un esquema de barreras no arancelarias con el fin de impulsar las exportaciones pero también restringir la entrada de productos extranjeros al mercado nacional, bajo la perspectiva de asegurar ser más competitivos , desde luego el articulo busca determinar cuáles son los obstáculos que afrontan los exportadores colombianos , no obstante el trabajo constituye una matriz analítica que permite ver la injerencia de estas medidas no arancelarias en el comercio , a partir de la evidencia recogida para el caso Chileno en 1995 como resultados de la Ronda de Uruguay.

  9. Aplicación de la Teoría de Restricciones (TOC a la gestión de facturación de las Empresas Sociales del Estado, ESE Una contribución al Sistema de Seguridad Social en Colombia

    Directory of Open Access Journals (Sweden)

    Iván Darío López López

    2007-06-01

    Full Text Available Los hospitales públicos de Colombia, denominados Empresas Sociales del Estado, ESE, Prestadoras de Servicios de Salud, mantienen conflictos con las Entidades Promotoras de Salud (EPS y las Administradoras del Régimen Subsidiado (ARS, debido a las facturas de cobro que las entidades hospitalarias envían a estas instituciones y son devueltas por inconsistencias en su diligenciamiento. Este hecho acarrea demoras en el pago por servicios médicos prestados. En este artículo se describe la situación actual de los hospitales públicos en esta materia, se enuncia la estrategia de solución al problema detectado y se formula una aplicación práctica y sistemática para corregirlo bajo los principios de la teoría de restricciones.

  10. expansion method

    Indian Academy of Sciences (India)

    In this paper, we shall apply the (G /G)-expansion method to obtain the exact travelling wave solution of the two-dimensional ... In §3, we apply our method to the mentioned equations. In §4, some conclusions are ..... The exact solution obtained by this method can be used to check computer codes or as initial condition for ...

  11. El proceso de mejora continua a través de la teoría de las restricciones (TOC): aplicación a Fibroluz

    OpenAIRE

    Garnica Tacuri, Maritza Fernanda; Guevara Segarra, María Fernanda

    2008-01-01

    TOC (Teoría de las Restricciones) es una nueva filosofía de administración empresarial integral, que abarca producción, mercadeo, finanzas, contabilidad y ejecuciones de proyectos; considera al Sistema (empresa), como un todo, no busca las eficiencias locales de cada parte del sistema, busca la eficiencia global; su única "Meta" es ganar dinero ahora y en el futuro, esta "Meta"podría alcanzarse de manera infinita, si no existieran factores que la limiten, factores a los que en TOC, se los co...

  12. Restrições causadas pela incontinência urinária à vida da mulher Restricciones ocasionadas por la incontinencia urinaria en la vida de la mujer Urinary incontinence restrictions in women's life

    Directory of Open Access Journals (Sweden)

    Maria Helena Baena de Moraes Lopes

    2006-03-01

    Full Text Available O objetivo deste estudo foi identificar as restrições causadas pela incontinência urinária (IU à vida da mulher, considerando-se o tipo de incontinência, e verificar como manejam este problema. Trata-se de uma análise secundária de dados obtidos em estudo anterior, coletados por meio de entrevista com perguntas abertas e fechadas. A amostra foi composta por 164 mulheres com queixa de IU, internadas em clínicas de ginecologia e urologia de dois hospitais-escola da cidade de Campinas, SP. Apresentavam idade entre 25 e 85 anos e 104 (64% referiram uma ou mais restrições. Citaram alterações nas atividades sexuais (40,9%, sociais (33,5%, domésticas (18,9% e ocupacionais (15,2%. A incontinência urinária mista e a de urgência forem as que mais afetavam a vida das mulheres. A estratégia mais utilizada para minimizar a IU foi o uso de forro e/ou absorvente higiênico. Concluiu-se que a IU tem implicações negativas no cotidiano dessas mulheres.En este estudio se tuvo como objetivo identificar las restricciones causadas por la incontinencia urinaria (IU en la vida de la mujer, considerándose el tipo de incontinencia, y verificar cómo manejan este problema. Se trata de un análisis secundario de datos obtenidos en un estudio anterior, recolectados por medio de entrevista con preguntas abiertas y cerradas. La muestra estuvo compuesta por 164 mujeres con queja de IU, internadas en clínicas de ginecología y urología de dos hospitales docentes de la ciudad de Campinas, SP. Las mujeres tenían entre 25 y 85 años de edad, habiendo relatado 104 (64% de ellas una o más restricciones. Citaron alteraciones en las actividades sexuales (40,9%, sociales (33,5%, domésticas (18,9% y ocupacionales (15,2%. La incontinencia urinaria mixta y la de urgencia fueron las que más afectaban la vida de las mujeres. La estrategia más utilizada para minimizar la IU fue el uso de paños y/o toallas higiénicas. Se concluyó que la IU tiene implicancias

  13. Teorías sobre cobertura con contratos de futuro

    Directory of Open Access Journals (Sweden)

    Aragó Mananza Vicent

    2009-10-01

    Full Text Available En este trabajo se presenta una revisión de las principales teorías sobre cobertura con contratos de futuro y de los distintos métodos de estimación utilizados para determinar el ratio de cobertura óptimo. La aproximación a la cobertura más utilizada en la literatura especializada es la basada en el modelo de la teoría de carteras. No obstante, debido a sus hipótesis relacionadas con la función de utilidad del inversor y con las propiedades de la función de distribución de los rendimientos, XI han surgido nuevas propuestas (por ejemplo, las construidas a partir del coeficiente de Gini y el concepto de Lower Partial Moments, que intentan reducir dichas restricciones.

  14. Técnicas borrosas para el análisis de la sensibilidad en la selección de carteras con restricciones de diversificación

    Directory of Open Access Journals (Sweden)

    Liern, Vicente

    Full Text Available We use fuzzy set theory to obtain alternative solutions to the Portfolio Selection Problemthat can better fit the inverstor’s preferences about the expected return and the corresponding risk of theefficient portfolio he or she finally chooses. We show by means of an example that, when diversificationconstraints are incorporated into the portfolio selection problem, the characteristics of the optimal efficientportfolio (composition, risk and expected return can be very sensitive to small variations of the parametersasociated to the investor’s subjective preferences, and then the fuzzy alternatives provided by our methodcan substantially improve the investor’s satisfaction.

  15. Técnicas borrosas para el análisis de la sensibilidad en la selección de carteras con restricciones de diversificación

    Directory of Open Access Journals (Sweden)

    Ivorra, Carlos

    2012-01-01

    Full Text Available We use fuzzy set theory to obtain alternative solutions to the Portfolio Selection Problemthat can better fit the inverstor’s preferences about the expected return and the corresponding risk of theefficient portfolio he or she finally chooses. We show by means of an example that, when diversificationconstraints are incorporated into the portfolio selection problem, the characteristics of the optimal efficientportfolio (composition, risk and expected return can be very sensitive to small variations of the parametersasociated to the investor’s subjective preferences, and then the fuzzy alternatives provided by our methodcan substantially improve the investor’s satisfaction.

  16. Control Multivariable Centralizado con Desacoplo para Aerogeneradores de Velocidad Variable

    Directory of Open Access Journals (Sweden)

    Miguel E. González

    2010-10-01

    Full Text Available Resumen: El diseño de sistemas de control para aerogeneradores de velocidad variable representa un reto importante ya que se trata de procesos multivariables no lineales, con fuertes perturbaciones, diversas restricciones y gran interacción entre sus variables. Bajo este escenario se debe generar eficientemente la potencia eléctrica y al mismo tiempo regular la velocidad de giro de la turbina. En este trabajo se proponen varios esquemas de control multivariable, con el objetivo de mejorar el rendimiento de los aerogeneradores atenuando los efectos de la interacción entre sus variables. La solución propuesta se basa en controladores PID con diseños del tipo descentralizado, centralizado con diversas redes de desacoplo y un esquema con cuatro PI. El comportamiento del aerogenerador se describe mediante un modelo matemático no lineal, que se linealiza para obtener una matriz de funciones de transferencia, a partir de la cual se diseñan los controladores. Finalmente se realiza un análisis comparativo para determinar qué controlador presenta mejores resultados, aplicando perturbaciones con un modelo de la velocidad del viento y cambios aleatorios de la carga eléctrica. Palabras Clave: Aerogenerador, Control Multivariable, Modelado e Interacción

  17. DESARROLLO E IMPLEMENTACIÓN DE UN MODELO DE TEORÍA DE RESTRICCIONES PARA SINCRONIZAR LAS OPERACIONES EN LA CADENA DE SUMINISTRO

    Directory of Open Access Journals (Sweden)

    William Marín Marín

    Full Text Available En este artículo se presenta una propuesta metodológica y práctica que permite sincronizar las operaciones y las decisiones en una cadena de suministro de una empresa del sector de revestimientos cerámicos en Colombia. Para ello se utilizaron dos herramientas de Teoría de Restricciones (TOC: la primera asociada a la sincronización de operaciones de la cadena de suministro (método Drum-Buffer-Rope, y la segunda, al desarrollo de una herramienta contable que permita mejorar la toma de decisiones de cada miembro de la cadena de suministro (Contabilidad de Throughput. Los resultados de la implementación muestran que mediante un análisis integral de la cadena de suministro puede mejorarse el desempeño de métricas globales como el nivel de servicio al cliente, el cumplimiento de los programas de producción, el costo de inventarios de materias primas y producto terminado, y la productividad de la empresa.

  18. Restricciones ontológicas en la política de calidad del aire en Bogotá

    Directory of Open Access Journals (Sweden)

    Héctor García Lozada

    2009-11-01

    Full Text Available Se examinan tres momentos de la política de calidad del aire en Bogotá (1974-2007, desde la perspectiva constructivista y desde el análisis crítico del discurso, con la intención de develar los paradigmas que sustentan estas decisiones así como la influencia de los actores sociales, en el contexto de un mundo globalizado y neoliberal. La precaria comprensión de la problemática le imprime a las políticas un sello de inoperancia que supera ampliamente las expectativas que sugieren sus textos, pero permite que la tecno-burocracia justifique el cumplimiento de sus obligaciones sin que se logren transformar o revertir las situaciones indeseables. / Three moments of the Bogota´s air quality policies (1974-2007 are examined, from the constructivist perspective and of the critical analysis of the discourse, with the purpose of reveal the paradigms that sustain these decisions as well as the influence of the social actors, in the context of an globalized and neoliberal world. The precarious comprehension of the problems prints on the policies ones a stamp of ineffectiveness that overcomes widely the expectations that suggest his texts but it allows that the tecno-bureaucracy should justify the fulfillment of his obligations without one manages to transform, or reverse, the undesirable situations

  19. Bridges Expansion Joints

    OpenAIRE

    Sergey W. Kozlachkow

    2012-01-01

    The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  20. On skin expansion.

    Science.gov (United States)

    Pamplona, Djenane C; Velloso, Raquel Q; Radwanski, Henrique N

    2014-01-01

    This article discusses skin expansion without considering cellular growth of the skin. An in vivo analysis was carried out that involved expansion at three different sites on one patient, allowing for the observation of the relaxation process. Those measurements were used to characterize the human skin of the thorax during the surgical process of skin expansion. A comparison between the in vivo results and the numerical finite elements model of the expansion was used to identify the material elastic parameters of the skin of the thorax of that patient. Delfino's constitutive equation was chosen to model the in vivo results. The skin is considered to be an isotropic, homogeneous, hyperelastic, and incompressible membrane. When the skin is extended, such as with expanders, the collagen fibers are also extended and cause stiffening in the skin, which results in increasing resistance to expansion or further stretching. We observed this phenomenon as an increase in the parameters as subsequent expansions continued. The number and shape of the skin expanders used in expansions were also studied, both mathematically and experimentally. The choice of the site where the expansion should be performed is discussed to enlighten problems that can lead to frustrated skin expansions. These results are very encouraging and provide insight into our understanding of the behavior of stretched skin by expansion. To our knowledge, this study has provided results that considerably improve our understanding of the behavior of human skin under expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Finite element model for expansive stress due to corrosion of reinforced concrete structures; Analisis con elemento finito de los esfuerzos expansivos por corrosion en las estructuras de concreto reforzado

    Energy Technology Data Exchange (ETDEWEB)

    Castorena Gonzalez, J.H.; Calderon Guillen, J.A. [Universidad Autonoma de Sinaloa, Los Mochis, Sinaloa (Mexico)]. E-mail: kstor28@yahoo.com.mx; cajoel_99@yahoo.com; Almeraya Calderon, F.; Gaona Tiburcio, C. [Centro de Investigacion en Materiales Avanzados, S.C., Chihuahua, Chihuahua (Mexico)]. E-mail: facundo.almeraya@cimav.edu.mx; citlalli.gaona@cimav.edu.mx; Almaral Sanchez, J.L. [Universidad Autonoma de Sinaloa, Los Mochis, Sinaloa (Mexico)]. E-mail: jalmaral@gmail.com; Martinez Villafane, A. [Centro de Investigacion en Materiales Avanzados, S.C., Chihuahua, Chihuahua (Mexico)]. E-mail: martinez.villafane@cimav.edu.mx

    2011-01-15

    The corrosion in the reinforcement steel is a problem that diminishes the useful life of reinforced concrete structures, reside committing its structural security. In the available models to estimate the mechanical effect of the corrosion, it is assumed that the corroded steel, through the oxides that grow to its surroundings, exercises a pressure on the surrounding concrete supposing a problem of plane stress or plane strain. In this work, the problem is modeled with three-dimensional finite element starting from an experiment on a subjected cylinder to accelerated corrosion, with strain gage to measure the pressure indirectly in the interface steel-concrete. From the results obtained it can be concluded that the effect of the length of corroded steel, anodic length, has a significant effect on the magnitude of the pressure in the interface steel-concrete, fact that can be used to improve the existing models. [Spanish] La corrosion en el acero de refuerzo es un problema que disminuye la vida util en las estructuras de concreto reforzado, ademas de comprometer su seguridad estructural. En los modelos disponibles para estimar el efecto mecanico de la corrosion, se supone que el acero corroido, a traves de los oxidos que crecen a su alrededor, ejercen una presion sobre el concreto circundante suponiendo un problema de esfuerzos o deformaciones planas, En el presente trabajo, se modela el problema con elemento finito tridimensional a partir de un experimento sobre un cilindro de concreto reforzado sometido a corrosion acelerada, instrumentado para medir indirectamente la presion en la interfase acero-concreto. De los resultados obtenidos se concluye que el efecto de la longitud de acero corroido, longitud anodica, tiene un efecto significativo sobre la magnitud de la presion en la interfase acero-concreto, hecho que puede ser utilizado para mejorar los modelos existentes.

  2. Bridges Expansion Joints

    Directory of Open Access Journals (Sweden)

    Sergey W. Kozlachkow

    2012-05-01

    Full Text Available The survey is concerned with the expansion joints, used in bridge constructions to compensate medium and significant operational linear and spatial displacements between adjacent spans or between bridge span and pier. The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting the modern demands imposed to expansion joints.

  3. Análisis del contexto de oportunidades y restricciones políticas bajo el cual se ha llevado a cabo la movilización del pueblo Mapuche en Chile (2000-2010)

    OpenAIRE

    Morales Hernández, Yalima Fernanda

    2011-01-01

    Monografía de grado por medio de la cual a partir de la teoría de Estructura de Oportunidades y de restricciones Políticas de Sydney Tarrow, se analiza el contexto en el que la movilización mapuche emergió durante los dos últimos gobiernos del partido socialista chileno. Para ello en un primer momento se hizo un análisis histórico de la problemática indígena hasta el restablecimiento de la democracia en 1989. Paso seguido fueron analizadas las respuestas que dieron los gobiernos de Ricardo ...

  4. Análisis, estudio e identificación de elementos críticos en los procesos de servicio en el Tecnicentro Uncoauto Cía. Ltda., mediante la teoría de restricciones

    OpenAIRE

    Chacón Guazhco, Bruno Fernando; Jimbo Landi, Wilson Roberto

    2008-01-01

    El presente trabajo aplica la Teoría de las Restricciones (TOC) al igual que conocimientos estadísticos, control de la producción, simulación mediante software y otros herramientas de Ingeniería Industrial en una empresa joven en el mercado, que tiene áreas definidas para el mantenimiento automotriz, y ha sabido disciplinadamente realizar la acumulación de sus datos históricos que le permitirán a corto plazo conocer su realidad y posteriormente proyectarse hacia el futuro sobre bases sólidas,...

  5. Bridges Expansion Joints

    National Research Council Canada - National Science Library

    Sergey W. Kozlachkow

    2012-01-01

    .... The analysis of design features of these types of expansion joints, their advantages and disadvantages, based on operational experience justified the necessity to design constructions, meeting...

  6. Conformal expansions and renormalons

    CERN Document Server

    Brodsky, S J; Grunberg, G; Rathsman, J; Brodsky, Stanley J.; Gardi, Einan; Grunberg, Georges; Rathsman, Johan

    2001-01-01

    The coefficients in perturbative expansions in gauge theories are factoriallyincreasing, predominantly due to renormalons. This type of factorial increaseis not expected in conformal theories. In QCD conformal relations betweenobservables can be defined in the presence of a perturbative infraredfixed-point. Using the Banks-Zaks expansion we study the effect of thelarge-order behavior of the perturbative series on the conformal coefficients.We find that in general these coefficients become factorially increasing.However, when the factorial behavior genuinely originates in a renormalonintegral, as implied by a postulated skeleton expansion, it does not affect theconformal coefficients. As a consequence, the conformal coefficients willindeed be free of renormalon divergence, in accordance with previousobservations concerning the smallness of these coefficients for specificobservables. We further show that the correspondence of the BLM method with theskeleton expansion implies a unique scale-setting procedure. Th...

  7. Expansion ortopedica maxilar con ortodoncia osteogenica periodontalmente acelerada

    National Research Council Canada - National Science Library

    Lopez Buitrago, Diego Fernando; Jaramillo Abadia, Isabel Cristina

    2014-01-01

    ... aparatos de disyuncion maxilar. Proposito: Analizar las aproximaciones terapeuticas actuales, como la ortodoncia osteogenica periodontalmente acelerada, que ofrecen alternativas de tratamiento en casos complejos, disminuyen la gravedad...

  8. Resonant state expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lind, P.

    1993-02-01

    The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.).

  9. Cylinder expansion test and gas gun experiment comparison

    Energy Technology Data Exchange (ETDEWEB)

    Harrier, Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-30

    This is a summer internship presentation by the Hydro Working Group at Los Alamos National Laboratory (LANL) and goes into detail about their cylinder expansion test and gas gun experiment comparison. Specifically, the gas gun experiment is detailed along with applications, the cylinder expansion test is detailed along with applications, there is a comparison of the methods with pros and cons and limitations listed, the summer project is detailed, and future work is talked about.

  10. Establecimiento del cálculo del diámetro de cresta exterior de un engranaje cónico con técnicas de grafos. // Procedure for the calculation of outer tip diameter on straight bevel gear by means of graphs technique.

    OpenAIRE

    G. González Rey

    2007-01-01

    Mediante un modelo matemático son dadas las principales relaciones entre los parámetros geométricos básicos requeridosen la evaluación del diámetro de cresta exterior de un engranaje ortogonal de ruedas cónicas con dientes rectos y suma decorrecciones radiales iguales a cero. Adicionalmente, serán brindados algunos resultados que asocian la correspondenciaentre una geometría racional y la capacidad de carga de un engranaje cónico con restricciones del diámetro de crestaexterior. Para la deter...

  11. Virial Expansion Bounds

    Science.gov (United States)

    Tate, Stephen James

    2013-10-01

    In the 1960s, the technique of using cluster expansion bounds in order to achieve bounds on the virial expansion was developed by Lebowitz and Penrose (J. Math. Phys. 5:841, 1964) and Ruelle (Statistical Mechanics: Rigorous Results. Benjamin, Elmsford, 1969). This technique is generalised to more recent cluster expansion bounds by Poghosyan and Ueltschi (J. Math. Phys. 50:053509, 2009), which are related to the work of Procacci (J. Stat. Phys. 129:171, 2007) and the tree-graph identity, detailed by Brydges (Phénomènes Critiques, Systèmes Aléatoires, Théories de Jauge. Les Houches 1984, pp. 129-183, 1986). The bounds achieved by Lebowitz and Penrose can also be sharpened by doing the actual optimisation and achieving expressions in terms of the Lambert W-function. The different bound from the cluster expansion shows some improvements for bounds on the convergence of the virial expansion in the case of positive potentials, which are allowed to have a hard core.

  12. Wake Expansion Models

    DEFF Research Database (Denmark)

    Branlard, Emmanuel Simon Pierre

    2017-01-01

    Different models of wake expansion are presented in this chapter: the 1D momentum theory model, the cylinder analog model and Theodorsen’s model. Far wake models such as the ones from Frandsen or Rathmann or only briefly mentioned. The different models are compared to each other. Results from thi...... this chapter are used in Chap. 16 to link near-wake and far-wake parameters and in Chap. 20 to study the influence of expansion on tip-losses....

  13. Nuclear expansion with excitation

    Energy Technology Data Exchange (ETDEWEB)

    De, J.N. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Samaddar, S.K. [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Vinas, X. [Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain); Centelles, M. [Departament d' Estructura i Constituents de la Materia, Facultat de Fisica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona (Spain)]. E-mail: mario@ecm.ub.es

    2006-07-06

    The expansion of an isolated hot spherical nucleus with excitation energy and its caloric curve are studied in a thermodynamic model with the SkM{sup *} force as the nuclear effective two-body interaction. The calted results are shown to compare well with the recent experimental data from energetic nuclear collisions. The fluctuations in temperature and density are also studied. They are seen to build up very rapidly beyond an excitation energy of {approx}9 MeV/u. Volume-conserving quadrupole deformation in addition to expansion indicates, however, nuclear disassembly above an excitation energy of {approx}4 MeV/u.

  14. Uniform gradient expansions

    Directory of Open Access Journals (Sweden)

    Massimo Giovannini

    2015-06-01

    Full Text Available Cosmological singularities are often discussed by means of a gradient expansion that can also describe, during a quasi-de Sitter phase, the progressive suppression of curvature inhomogeneities. While the inflationary event horizon is being formed the two mentioned regimes coexist and a uniform expansion can be conceived and applied to the evolution of spatial gradients across the protoinflationary boundary. It is argued that conventional arguments addressing the preinflationary initial conditions are necessary but generally not sufficient to guarantee a homogeneous onset of the conventional inflationary stage.

  15. Teoría de restricciones aplicada a la cadena de suministros en un operador logístico de productos farmacéuticos

    OpenAIRE

    Barrero Muñoz, Diana; Guerrero Mora, Karina Elizabeth

    2013-01-01

    En las instituciones hospitalarias es fundamental el tema relacionado con los medicamentos y dispositivos médicos para la atención del paciente, por lo tanto el mecanismo de adquisición y disponibilidad de éstos productos, ha llevado a la participación masiva de operadores logísticos (Outsoursing) interviniendo áreas de la cadena de suministros, desde el punto de fabricación con el producto terminado hasta la dispensación del medicamento o dispositivo médico, para que ser usado o administrado...

  16. Evaluación externa de los cambios funcionales y la marcha tras una sesión de miofibrotomía múltiple en escolares con diplejía espástica

    OpenAIRE

    Gómez-Andrés, David; Pulido-Valdeolivas, Irene; Martín-Gonzalo, Juan Andrés; López-López, Javier; Martínez-Caballero, Ignacio; Gómez-Barrena, Enrique; Rausell, Estrella

    2014-01-01

    Introducción. Unos 23.000 pacientes con espasticidad han optado voluntariamente por la miofibrotomía múltiple (MFM), una técnica alternativa consistente en seccionar tejidos blandos para liberar restricciones articulares. Iniciada por Ulzibat (Rusia), se realiza fuera de controles clínicos ortodoxos. Objetivo. Evaluar externamente los efectos de la MFM sobre la funcionalidad motora y la marcha. Pacientes y métodos. Estudio observacional autocontrolado que evalúa cambios en variabl...

  17. AUTO-EXPANSIVE FLOW

    Science.gov (United States)

    Physics suggests that the interplay of momentum, continuity, and geometry in outward radial flow must produce density and concomitant pressure reductions. In other words, this flow is intrinsically auto-expansive. It has been proposed that this process is the key to understanding...

  18. Rethinking expansive learning

    DEFF Research Database (Denmark)

    Kolbæk, Ditte; Lundh Snis, Ulrika

    discussion forum on Google groups, they created new ways of reflecting and learning. We used netnography to select qualitative postings from the online community and expansive learning concepts for data analysis. The findings show how students changed practices of organisational learning...

  19. Validación de un algoritmo híbrido del pso con el método simplex y de topología de evolución paramétrica

    OpenAIRE

    CORREA, RODRIGO; BEGAMBRE, OSCAR; CARRILLO E., JULIO C.

    2011-01-01

    Este artículo describe algunos de los aspectos más importantes relacionados con la experimentación numérica de un híbrido del algoritmo PSO (Particle Swarm Optimization) con el tradicional método simplex modificado de Nelder-Mead. El híbrido de estas dos técnicas de optimización sin restricciones se realizó con una topología que permite optimizar en cada iteración los parámetros del algoritmo PSO utilizando el método simplex modificado. Se realizaron experimentos numéricos con este algoritmo ...

  20. Teorías sobre cobertura con contratos de futuro

    National Research Council Canada - National Science Library

    Vicent Aragó Mananza

    2009-01-01

    ... de distribución de los rendimientos, XI han surgido nuevas propuestas (por ejemplo, las construidas a partir del coeficiente de Gini y el concepto de Lower Partial Moments), que intentan reducir dichas restricciones.

  1. IKEA's International Expansion

    OpenAIRE

    Harapiak, Clayton

    2013-01-01

    This case concerns a global retailing firm that is dealing with strategic management and marketing issues. Applying a scenario of international expansion, this case provides a thorough analysis of the current business environment for IKEA. Utilizing a variety of methods (e.g. SWOT, PESTLE, McKinsey Matrix) the overall objective is to provide students with the opportunity to apply their research skills and knowledge regarding a highly competitive industry to develop strategic marketing strateg...

  2. Character expansion of matrix integrals

    OpenAIRE

    van de Leur, J. W.; Orlov, A. Yu.

    2016-01-01

    We consider character expansion of tau functions and multiple integrals in characters of orhtogonal and symplectic groups. In particular we consider character expansions of integrals over orthogonal and over symplectic matrices.

  3. Mejoramiento del proceso productivo en la Planta Pifo de Eni Ecuador S.A. aplicando el enfoque de procesos y la teoría de restricciones

    OpenAIRE

    Mosquera Lastra, Edison Ramiro

    2014-01-01

    215 hojas : ilustraciones, 29 x 21 cm + CD-ROM 5697 El objetivo del presente trabajo fue mejorar el proceso productivo en el envasado de glp y reparación de cilindros en la Planta de envasado Pifo de Eni Ecuador S.A., para esto se realizó un modelamiento del proceso productivo con base en la adopción del enfoque en procesos el cual sirvió para orientar a la organización hacia el cliente y hacia sus objetivos. Luego se procedió a realizar un estudio para determinar los tiempos de cada acti...

  4. Aplicación de la Teoría de Restricciones en la gestión de la seguridad del paciente

    OpenAIRE

    León Vanegas, Yuli Licet

    2013-01-01

    La seguridad del paciente constituye una prioridad y un reto para los organismos Gubernamentales y para las instituciones de salud tanto a nivel nacional como internacional (Sescam, 2007), quienes han emprendido una búsqueda de soluciones por medio de diferentes metodologías y estrategias que permitan reducir al máximo los riesgos de la atención de salud para el paciente (Ministerio de Sanidad y Consumo, 2002). Aunque se cuenta con mejores sistemas o metodología de análisis y sistemas de noti...

  5. O-PRECISION: UNA ALTERNATIVA METODOLÓGICA DE TRABAJO CON PERSONAS CON DISCAPACIDAD FÍSICA E INTELECTUAL

    Directory of Open Access Journals (Sweden)

    Victoria Rey Niño

    2015-04-01

    Full Text Available La Clasificación Internacional del Funcionamiento, de la Discapacidad y de la Salud (CIF define la discapacidad como un término genérico que abarca deficiencias, limitaciones de la actividad y restricciones a la participación. En este caso hablamos de personas con discapacidad física e intelectual por parálisis cerebral, lo que significa que su acceso al mundo de la actividad física se encuentra en la mayoría de los casos muy restringido. Pero existe una modalidad de la orientación llamada Orientación de Precisión u O-Trail que, según la Federación Deportiva de Orientación (FEDO, ha sido adaptada para ofrecer a todos, independientemente de su sexo, edad, capacidad o discapacidad física, la oportunidad de participar en igualdad de condiciones en una típica competición de orientación. Como sugiere Arribas y Sánchez (1998: “En la actividad física podemos encontrar recursos y herramientas de intervención adecuadas a cada contexto y etapa de ciclo vital además, a través de su práctica pueden verse satisfechas determinadas necesidades e intereses personales y grupales, que pueden ser tratados desde un planteamiento educativo” . Este proyecto tiene la intención de ir más allá y pretende utilizar la Orientación de precisión como una herramienta para implementar una alternativa metodológica de trabajo a las actividades que se llevan a cabo con un colectivo de personas con discapacidad física e intelectual en la Asociación Cultural y rehabilitadora de Discapacitados Físicos de Palencia, desarrollando y estimulando sus aspectos intelectuales y sociales mediante una disciplina deportiva desconocida para ellos, con la intención de que aumente su motivación por participar.Objetivo: Implementar la O-Precisión como alternativa metodológica de trabajo con personas con discapacidad física e intelectual con el fin de desarrollar sus capacidades cognitivas y aumentar su autoestima.

  6. Cementos con cenizas volantes

    Directory of Open Access Journals (Sweden)

    Ossa M., Mauricio

    1984-03-01

    Full Text Available Almost all the studies carried out on cements with the addition of flying ash refer to their characteristics and behaviours in pastes, mortars and concretes, always in relation with Portland cement. This time, there has been developed an experimental work oriented to relate between themselves the cements with additions of flying ash and of natural puzzolan. For this there were manufactured on laboratory scale cements of both types, using the same raw materials, clinker and plaster, and as variables, different percentages of the two additions, which previously complied with the standard requisites concerning their puzzolanic (?? activities. The quality of the cements manufactured was adequate and in accord with that of Portland-puzzolanic (?? cement obtained on an industrial scale with the same clinkers, plaster and natural puzzolan (?? of this study. Later there were determined the characteristics of the experimental cements and normal mortars were prepared for carrying out physical and mechanical tests. The test results indicated that the cements with addition of flying ash (CCV require less water for normal consistency, present greater times of forging and fewer expansions in autoclave than the cements with the addition of puzzolan (CP. The hydration heats at 7 and 28 days were approximately similar for both types of cement. In normal mortars, the CCV cements showed less retraction of drying, greater retentivenness and greater fluidity (for the same quantity of water than the CP cements. In the exudation tests it was observed that this depends more on the fineness than the type of addition. Finally, the mechanical tests showed that the resistances to compression and flexotraction of the mortars with CCV cements are lesser at ages less than 14 days (about 5 to 10% at one day of age, but from then on become greater than those of mortars with CP cements, with growing differences which reach 15% in compression tests, at 120 days of age, for

  7. Métodos de optimización para el problema de ruteo de vehículos con inventarios y ventanas de tiempo duras

    Directory of Open Access Journals (Sweden)

    Eliseo Pérez Kaligari

    2015-10-01

    Full Text Available El problema estudiado considera las decisiones de ruteo de vehículos con inventarios y restricciones de ventanas de tiempo duras (IRPTW en una cadena de abastecimiento compuesta por un depósito y múltiples minoristas. Se asume un horizonte de planeación discreto y finito en donde las decisiones por optimizar son: las cantidades a aprovisionar a los minoristas y, simultáneamente, la secuencia de minoristas a visitar en cada periodo de tiempo. El sistema cuenta con un sólo vehículo de capacidad limitada, restricciones de capacidad de almacenamiento de los minoristas, y tasa de producción limitada del depósito. Se requiere satisfacer la demanda que tienen los minoristas. Se asume que los minoristas tienen demanda determinística y no homogénea. Se propone una formulación matemática basada en programación entera mixta y se estudia el impacto que tiene la configuración de las ventanas de tiempo sobre las decisiones de ruteo de vehículos con inventarios, a través de dos métodos de optimización. El primer método optimiza las decisiones de forma simultánea, mientras que el segundo método propuesto considera las decisiones de forma secuencial, lo que lo convierte en un método heurístico. Se presenta un estudio computacional con 80 instancias adaptadas de la literatura. Los resultados muestran que el método de optimización simultáneo tiene un desempeño mejor que el método heurístico de optimización secuencial generando ahorros potenciales en los costos logísticos de al menos 6%.

  8. Restricciones y prejuicios en torno a las relaciones sentimentales y familiares de la comunidad esclava en tiempos de la independencia de Colombia

    Directory of Open Access Journals (Sweden)

    Roger Pita Pico

    2014-01-01

    Full Text Available e ste artículo aborda la complejidad de la vida afectiva de la población esclava durante el proceso de i ndependencia de c olombia. e n términos generales, muchas de las limitaciones establecidas durante el periodo colonial siguieron vigentes, tanto en los vínculos familiares de los esclavos como en las relaciones sentimentales entabladas con el elemento blanco. a l final, fueron muy pocos los avances en esta materia debido a la posición asumida por los amos en defensa del sistema esclavista y de sus intereses como propietarios, y a la falta de compromiso por parte de las autoridades españolas y republicanas. La crisis económica y los efectos sociales de la guerra ahondarían aún más la fragmentación de la comunidad esclava.

  9. Vulnerabilidad social de las mujeres y la población indígena en Oaxaca, 2005: restricciones y estrategias

    Directory of Open Access Journals (Sweden)

    Rafael G. Reyes Morales

    2007-05-01

    Full Text Available La discusión sobre vulnerabilidad de las mujeres y los indígenas en el estado de Oaxaca son: la exclusión de beneficios de las políticas públicas de bienestar, el poder adquisitivo y las estrategias para superar la condición de vulnerabilidad. Los hallazgos del artículo contradicen la situación de relativa precariedad de los hogares con jefatura femenina reportada por la literatura especializada. La migración aparece como un instrumento que contribuye a la equidad de género y permite elevar la escolaridad de la población indígena.

  10. Algunas novelas de Darío Fernández-Flórez: de Zarabanda (1944 a Alta Costura (1954. Temas escabrosos en tiempos de restricciones moralistas

    Directory of Open Access Journals (Sweden)

    Montejo Gurruchaga, Lucía

    2008-06-01

    Full Text Available Dario Fernández-Flórez begins in 1944 with Zarabanda a narrative style of intellectual eroticism and inmoral atmosphere which attracted no attention. Six years later he published Lola, espejo oscuro the recollections of a high prostitute. The novel was an scandal and an immediate success. Although the topic and its treatment were odd at the time because the strict moral values which mantained Franco´s regime were ignored, the novel was published with no cuts at all. Censorship was deaf to all the voices that warned of its dangers. This had an explanation: Darío Fernández-Flórez held an important post in the Propaganda National Service. After his dismissal censors were less lenient.Darío Fernández-Flórez inicia en 1944 con Zarabanda una narrativa de erotismo intelectualizado y ambiente amoral que no tuvo ningún eco. Seis años después publicará Lola, espejo oscuro, las memorias de una prostituta de alto copete. La novela suscitó un gran escándalo y su éxito fue inmediato. Aunque el tema y su tratamiento eran inusitados en aquellos momentos porque la obra daba al traste con los estrictos valores morales que sustentaban el régimen franquista, la novela fue publicada sin recortes; la censura hizo oídos sordos a todas las voces que alertaban de su peligro. Este hecho tiene una explicación: Darío Fernández-Flórez ocupaba un cargo importante en el Servicio Nacional de Propaganda. Tras su cese, los censores serán menos benevolentes.

  11. Conformal expansions and renormalons

    CERN Document Server

    Gardi, E; Gardi, Einan; Grunberg, Georges

    2001-01-01

    The large-order behaviour of QCD is dominated by renormalons. On the other hand renormalons do not occur in conformal theories, such as the one describing the infrared fixed-point of QCD at small beta_0 (the Banks--Zaks limit). Since the fixed-point has a perturbative realization, all-order perturbative relations exist between the conformal coefficients, which are renormalon-free, and the standard perturbative coefficients, which contain renormalons. Therefore, an explicit cancellation of renormalons should occur in these relations. The absence of renormalons in the conformal limit can thus be seen as a constraint on the structure of the QCD perturbative expansion. We show that the conformal constraint is non-trivial: a generic model for the large-order behaviour violates it. We also analyse a specific example, based on a renormalon-type integral over the two-loop running-coupling, where the required cancellation does occur.

  12. Permissible limit for mandibular expansion.

    Science.gov (United States)

    Motoyoshi, Mitsuru; Shirai, Sawa; Yano, Shinya; Nakanishi, Kotoe; Shimizu, Noriyoshi

    2005-04-01

    In recent years, mandibular expansion has been increasingly performed in conjunction with orthodontic treatment. Lateral tipping of the molars associated with mandibular expansion should, however, be considered, because excessive expansion may result in excessive buccal tooth inclination, which may disturb the occlusal relationship. This study was conducted to quantitatively clarify molar movement during mandibular expansion using the Schwarz appliance to determine the permissible limit of mandibular expansion as a clinical index for inclination movement. Inclinations in the masticatory surface of the first molar and intermolar width were measured before expansion (T1), after expansion (T2), and before edgewise treatment (T3). Lower plaster models from 29 subjects treated with expansion plates were used and compared with models from 11 control subjects with normal occlusion. The average treatment change (T1-T2) in intermolar width was 5.42 mm (standard deviation 1.98), and the average angle of buccal tooth inclination was 10.16 degrees (standard deviation 3.83). No significant correlation was found between age prior to treatment and the treatment period when they were compared with the intermolar width increments and inclination angles. There was a significant positive correlation between retention duration and the amount of expansion. The regression coefficient of the angle of buccal tooth inclination during expansion to the increment of the intermolar width was approximately 0.2. This means that 1 mm of expansion is accompanied by 5 degrees of molar lateral tipping. This coefficient is clinically useful for estimating the permissible limit for mandibular expansion.

  13. El portafolio docente a escrutinio: sus posibilidades y restricciones en la formación y evaluación del profesorado.

    Directory of Open Access Journals (Sweden)

    Frida Díaz Barriga Arceo

    2010-07-01

    Full Text Available A pesar del gran entusiasmo y amplia difusión que han despertado los portafolios como recurso innovador en la evaluación y formación del profesorado, debe realizarse un análisis de su sentido y alcances, para evitar su empleo indiscriminado y poco crítico. En este artículo se revisa el surgimiento y supuestos educativos de los portafolios docentes, así como algunos estudios que dan cuenta de su potencialidad como recurso de evaluación auténtica y reflexión sobre la propia identidad y práctica educativa de los docentes en formación. Asimismo, se revisan una serie de críticas y notas precautorias respecto a su empleo, sobre todo cuando se pretende su aplicación como instrumento estandarizado a gran escala. Se concluye que su mayor potencial reside en promover la autoevaluación reflexiva de los profesores y en la posibilidad de impulsar un cambio en la cultura de la evaluación en las instituciones educativas. Al mismo tiempo, el gran riesgo consiste en la proliferación de una mirada exclusivamente técnica y sesgada, centrada en los instrumentos de calificación, con poco fundamento teórico e investigación empírica.

  14. Burial Ground Expansion Hydrogeologic Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Gaughan , T.F.

    1999-02-26

    Sirrine Environmental Consultants provided technical oversight of the installation of eighteen groundwater monitoring wells and six exploratory borings around the location of the Burial Ground Expansion.

  15. De la “maldición de la basura” y restricciones institucionales: una evaluación ambiental ex ante al desperdicio Nortecaucano

    Directory of Open Access Journals (Sweden)

    Cortés Landázury Raúl

    2012-05-01

    Full Text Available En el análisis de la brecha entre anhelos y realizaciones en materia de desarrollo sostenible en América latina, la mayoría de los argumentos se inclinan por interpretaciones de corte económico ortodoxo. Sin embargo, si se consideran los problemas ambientales anteriores e independientes del paradigma económico de turno, las razones para la persistencia y universalidad de estos fenómenos no deben buscarse meramente en este tipo de dimensión. Tal es el caso de la disposición final de residuos sólidos en el norte del departamento del Cauca, donde la eficiencia técnica en torno a la solución del problema traba con elementos de tipo ético y cultural que, quizás, se entiendan mejor desde la economía política. Este documento expone algunas interpretaciones del asunto, abordando la problemática a partir de la idea de fallo de coordinación derivado de la incongruencia entre mecanismos de decisión y acción colectiva. Por este motivo, se describe el contexto de la problemática, indicando el protagonismo de los factores de presión, el papel de las instituciones involucradas, los lineamientos generales de la solución técnica y la percepción de los actores a través de la medición económica de sus preferencias, y finalmente se concluye.

  16. Convergence of generalized eigenfunction expansions

    Directory of Open Access Journals (Sweden)

    Mayumi Sakata

    2007-05-01

    Full Text Available We present a simplified theory of generalized eigenfunction expansions for a commuting family of bounded operators and with finitely many unbounded operators. We also study the convergence of these expansions, giving an abstract type of uniform convergence result, and illustrate the theory by giving two examples: The Fourier transform on Hecke operators, and the Laplacian operators in hyperbolic spaces.

  17. On the Bantu expansion.

    Science.gov (United States)

    Rowold, Daine J; Perez-Benedico, David; Stojkovic, Oliver; Garcia-Bertrand, Ralph; Herrera, Rene J

    2016-11-15

    Here we report the results of fine resolution Y chromosomal analyses (Y-SNP and Y-STR) of 267 Bantu-speaking males from three populations located in the southeast region of Africa. In an effort to determine the relative Y chromosomal affinities of these three genotyped populations, the findings are interpreted in the context of 74 geographically and ethnically targeted African reference populations representing four major ethno-linguistic groups (Afro-Asiatic, Niger Kordofanin, Khoisan and Pygmoid). In this investigation, we detected a general similarity in the Y chromosome lineages among the geographically dispersed Bantu-speaking populations suggesting a shared heritage and the shallow time depth of the Bantu Expansion. Also, micro-variations in the Bantu Y chromosomal composition across the continent highlight location-specific gene flow patterns with non-Bantu-speaking populations (Khoisan, Pygmy, Afro-Asiatic). Our Y chromosomal results also indicate that the three Bantu-speaking Southeast populations genotyped exhibit unique gene flow patterns involving Eurasian populations but fail to reveal a prevailing genetic affinity to East or Central African Bantu-speaking groups. In addition, the Y-SNP data underscores a longitudinal partitioning in sub-Sahara Africa of two R1b1 subgroups, R1b1-P25* (west) and R1b1a2-M269 (east). No evidence was observed linking the B2a haplogroup detected in the genotyped Southeast African Bantu-speaking populations to gene flow from contemporary Khoisan groups. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Desarrollo de un modelo generalizado para realimentación de fuerza y torque en cirugía cardiotorácica robótica mínimamente invasiva: determinación de condiciones y restricciones Development of a generalized model for force and torque feedback in robotic minimally invasive cardiothoracic surgery: identification of conditions and restrictions

    Directory of Open Access Journals (Sweden)

    Vera Pérez

    2011-07-01

    Full Text Available INTRODUCCIÓN: los procedimientos de cirugía cardiotorácica mínimamente invasiva (MICS, su sigla en Inglés buscan reducir las complicaciones de las grandes disecciones. No obstante, ante la falta de contacto directo con el tejido por parte del cirujano, éste recibe una sensación parcial de tacto y fuerza, lo que puede originar errores de procedimiento, inadecuada fuerza aplicada al tejido y fatiga durante el acto quirúrgico. La inclusión de dispositivos robóticos con la técnica MICS ha potencializado las habilidades del cirujano para la manipulación de los tejidos, y aunque los desarrollos del mercado no cuentan aún con retroalimentación táctil, se trabaja en prototipos robóticos que incorporan realimentación de fuerza y torque. OBJETIVO: proponer las condiciones y restricciones relacionadas con la incorporación de realimentación de fuerza y torque en MICS robótica, aplicables a diferentes configuraciones de manipuladores, y analizar la implementación de dichas condiciones en un simulador quirúrgico. MATERIAL Y MÉTODOS: partiendo del análisis de necesidades durante procedimientos cardiotorácicos y las condiciones de cirugía mínimamente invasiva, se identificaron los requerimientos para garantizar reflexión de fuerza y se realizó un análisis matemático de dichas consideraciones. Finalmente, se verificaron los análisis matemáticos mediante técnicas de modelización y simulación utilizando la plataforma computacional Matlab®. RESULTADOS: se argumentaron tres tipos de consideraciones: a Cinemático: la existencia de un punto fijo, las formas de garantizarlo durante procedimientos MICS robóticos, y las trayectorias de movimiento que el manipulador sigue en aplicaciones de cirugía cardiotorácica; b Dinámico: la repercusión de fuerzas externas en el manipulador y la manera de considerarlas en el desarrollo de controladores que permitan al cirujano percibir una sensación de contacto con el tejido; c Sensorial

  19. TOPICAL REVIEW: Negative thermal expansion

    Science.gov (United States)

    Barrera, G. D.; Bruno, J. A. O.; Barron, T. H. K.; Allan, N. L.

    2005-02-01

    There has been substantial renewed interest in negative thermal expansion following the discovery that cubic ZrW2O8 contracts over a temperature range in excess of 1000 K. Substances of many different kinds show negative thermal expansion, especially at low temperatures. In this article we review the underlying thermodynamics, emphasizing the roles of thermal stress and elasticity. We also discuss vibrational and non-vibrational mechanisms operating on the atomic scale that are responsible for negative expansion, both isotropic and anisotropic, in a wide range of materials.

  20. Thermal Expansion of Polyurethane Foam

    Science.gov (United States)

    Lerch, Bradley A.; Sullivan, Roy M.

    2006-01-01

    Closed cell foams are often used for thermal insulation. In the case of the Space Shuttle, the External Tank uses several thermal protection systems to maintain the temperature of the cryogenic fuels. A few of these systems are polyurethane, closed cell foams. In an attempt to better understand the foam behavior on the tank, we are in the process of developing and improving thermal-mechanical models for the foams. These models will start at the microstructural level and progress to the overall structural behavior of the foams on the tank. One of the key properties for model characterization and verification is thermal expansion. Since the foam is not a material, but a structure, the modeling of the expansion is complex. It is also exacerbated by the anisoptropy of the material. During the spraying and foaming process, the cells become elongated in the rise direction and this imparts different properties in the rise direction than in the transverse directions. Our approach is to treat the foam as a two part structure consisting of the polymeric cell structure and the gas inside the cells. The polymeric skeleton has a thermal expansion of its own which is derived from the basic polymer chemistry. However, a major contributor to the thermal expansion is the volume change associated with the gas inside of the closed cells. As this gas expands it exerts pressure on the cell walls and changes the shape and size of the cells. The amount that this occurs depends on the elastic and viscoplastic properties of the polymer skeleton. The more compliant the polymeric skeleton, the more influence the gas pressure has on the expansion. An additional influence on the expansion process is that the polymeric skeleton begins to breakdown at elevated temperatures and releases additional gas species into the cell interiors, adding to the gas pressure. The fact that this is such a complex process makes thermal expansion ideal for testing the models. This report focuses on the thermal

  1. Strategic Complexity and Global Expansion

    DEFF Research Database (Denmark)

    Oladottir, Asta Dis; Hobdari, Bersant; Papanastassiou, Marina

    2012-01-01

    The purpose of this paper is to analyse the determinants of global expansion strategies of newcomer Multinational Corporations (MNCs) by focusing on Iceland, Israel and Ireland. We argue that newcomer MNCs from small open economies pursue complex global expansion strategies (CGES). We distinguish....... The empirical evidence suggests that newcomer MNCs move away from simplistic dualities in the formulation of their strategic choices towards more complex options as a means of maintaining and enhancing their global competitiveness....

  2. Estimates of expansion time scales

    Science.gov (United States)

    Jones, E. M.

    Monte Carlo simulations of the expansion of a spacefaring civilization show that descendants of that civilization should be found near virtually every useful star in the Galaxy in a time much less than the current age of the Galaxy. Only extreme assumptions about local population growth rates, emigration rates, or ship ranges can slow or halt an expansion. The apparent absence of extraterrestrials from the solar system suggests that no such civilization has arisen in the Galaxy.

  3. Ganho de peso nos pacientes portadores de mielomeningocele após tratamento com prótese vertical expansível de titânio para costela Aumento de peso en pacientes con mielomeningocele después del tratamiento con la prótesis vertical expansible de titanio para costilla Weight gain in patients with myelomeningocele after treatment with vertical expandable prosthetic titanium rib

    Directory of Open Access Journals (Sweden)

    Rafael Marques Ielpo

    2012-09-01

    Full Text Available OBJETIVO: Avaliar o ganho de peso e a variação do estado nutricional dos pacientes portadores de mielomeningocele torácica após o uso da prótese vertical expansível de titânio (VEPTR como opção para tratamento sem fusão da coluna vertebral. MÉTODOS: Estudo retrospectivo de oito pacientes (com média de idade de 5,3 anos; variando de 3,6 a 7,6 anos no momento da cirurgia inicial, portadores de mielomeningocele torácica que apresentavam escoliose, medida pelo método de Cobb, superior a 40º e cifose superior a 80º, tratados com VEPTR pelo grupo de Escoliose da AACD de São Paulo. Foram analisados os pesos, desvio-padrão em que cada paciente se encontrava na tabela idade versus peso referência da OMS e valores angulares da cifose, no pré-operatório, pós-operatório imediato e pós-operatório tardio. RESULTADOS: Houve ganho absoluto de peso em todos os pacientes, com média de 8,7 kg (variando de 3 a 20 kg. Seis pacientes (75% apresentaram ganho de peso e aumento do valor do desvio padrão, traduzindo-se em aproximação de seu peso com relação à mediana considerada normal da curva idade versus peso referência após o início do tratamento com VEPTR. CONCLUSÃO: O ganho de peso absoluto observado não foi acompanhado de melhora do estado nutricional e não houve relação entre correção da cifose e ganho de peso.OBJETIVO: Evaluar la ganancia de peso y el cambio en el estado nutricional de los pacientes con mielomeningocele torácico después de usar la prótesis vertical expandible de titanio (VEPTR como una opción para el tratamiento sin la fusión de la columna vertebral. MÉTODOS: Estudio retrospectivo de ocho pacientes (edad media de 5,3 años, entre 3,6 y 7,6 años en el momento de la cirugía inicial, con mielomeningocele torácico que tenían escoliosis , medida por el método de Cobb, con valores superiores a 40 º y cifosis mayores de 80 º, tratados con VEPTR en el Grupo de Escoliosis de la AACD en São Paulo. Se

  4. Análisis prospectivo de la base alimentaria en una lechería tropical con programación lineal

    Directory of Open Access Journals (Sweden)

    J. A Herrera

    Full Text Available El objetivo de la investigación fue analizar prospectivamente la base alimentaria de una lechería tropical, por medio de un modelo de optimización. Las variables de este modelo fueron: pasto estrella, leucaena asociada con guinea común, caña de azúcar y CT-115. Los requerimientos se estimaron para vacas de 425 kg de PV, con una producción de 4 kg/animal/día, y se establecieron ocho restricciones. El modelo fue resuelto con el programa WinQSB versión 2.0. La función objetivo fue maximizar la producción de MS por hectárea. La solución óptima indicó que la mayor parte del área debe corresponder al pasto estrella, con 45 % del total. El análisis de sensibilidad mostró que la producción de MS por hectárea de la caña de azúcar puede disminuir hasta 7,64 t y aumentar hasta un valor infinito, sin que se afecte la solución óptima obtenida. En el caso del pasto estrella, la disminución permisible sobrepasó el valor cero, y el incremento no debe ser superior a 6,30 t de MS/ha. De acuerdo con los amplios rangos que se lograron con los análisis de sensibilidad, se puede plantear que el modelo no es sensible a grandes cambios en los coeficientes en la función objetivo ni en las restricciones. La técnica matemática de programación lineal resultó una herramienta útil para el análisis prospectivo de la base alimentaria en una lechería tropical, con un enfoque de optimización

  5. Estimación y análisis de precios nodales como efecto de las restricciones de transmisión en el mercado mayorista de Colombia Assessment and analysis of local marginal prices as an effect of electric transmission constraints in the Colombian power market

    Directory of Open Access Journals (Sweden)

    Gallego Vega Luis Eduardo

    2010-12-01

    Full Text Available El presente artículo presenta los resultados de una investigación sobre la estimación y análisis de precios nodales para el sistema de transmisión nacional de Colombia, como una alternativa para analizar el efecto de las restricciones de transmisión en el mercado mayorista de Colombia. Esta alternativa se plantea contra el modelo actual del mercado mayorista, el cual consiste en un modelo uninodal del sistema, sin darle un tratamiento adecuado a las restricciones de transmisión. La investigación describe el modelamiento del sistema de transmisión nacional, el modelamiento de la operación del despacho económico en el país y una metodología de refinamiento que incluye tanto las restricciones eléctricas como operativas del sistema. Como resultados se presenta un análisis de los precios nodales obtenidos para cada área operativa del sistema de transmisión colombiano y un análisis sobre las rentas de congestión del sistema.This paper gives the results of research assessing and analysing local marginal prices in the national transmission grid as an alternative for analysing the effect of electric transmission constraints in the Colombian power market. This study compares the current one-bus model where a spot price is determined without considering transmission network constraints. It describes the modelling of the national transmission grid, power system operation and economic dispatch and a methodology for approaching the system’s electrical constraints and operational constraints. An analysis of local marginal prices for each operational zone in the Colombian power system is presented as a result of this modelling, as well as statistical modelling of congestion income

  6. Tratamento da escoliose em crianças com paralisia cerebral utilizando a prótese vertical expansível de titânio para costela (VEPTR Tratamiento de la escoliosis en niños con parálisis cerebral mediante la prótesis vertical expansible de titanio para las costillas (VEPTR Treatment of scoliosis in children with cerebral palsy using the vertical expandable prosthetic titanium rib (VEPTR

    Directory of Open Access Journals (Sweden)

    Kiyomori de Quental Tyba

    2011-01-01

    Full Text Available OBJETIVO: Avaliar o uso da prótese vertical expansível de titânio (VEPTR como opção de tratamento inicial da escoliose em crianças de baixa idade portadoras de paralisia cerebral. MÉTODOS: Foram avaliados 10 pacientes portadores de paralisia cerebral (PC tratados com VEPTR pelo grupo de escoliose da AACD de São Paulo. Caracterizavam-se por imaturidade esquelética e escoliose progressiva; sem deformidade grave no plano sagital. Realizamos avaliação da curva pelo método de Cobb no pré e pós-operatório e após dois anos de seguimento. RESULTADOS: A correção obtida com o uso do VEPTR no pós-operatório imediato foi em média de 41,4% nas radiografias iniciais sem tração (p = 0,005 e 9,1% (p = 0,055 nas radiografias com tração. Após quatro meses de pós-operatório mantiveram-se ganhos de 27,2% com relação ao início. Houve correção da obliquidade pélvica de 10,2º no pré-operatório para 5,4º em média (p = 0,007. As complicações ocorreram em seis pacientes (60% e em apenas um paciente foi necessária a retirada do VEPTR. CONCLUSÃO: O VEPTR é um método que obteve correção significativa no tratamento provisório das escolioses na PC, apesar de frequentes complicações de baixa morbidade.OBJETIVO: Evaluar el uso de la prótesis vertical expansible de titanio (VEPTR como opción de tratamiento inicial para la escoliosis en niños pequeños con parálisis cerebral. MÉTODOS: 10 pacientes con parálisis cerebral (PC fueron evaluados y tratados con VEPTR por el grupo de escoliosis de la AACD en Sao Paulo. Caracterizados por escoliosis progresiva inmadurez esquelética, sin deformidad grave en el plano sagital. Se evaluó la curva por el método de Cobb en el preoperatorio, posoperatorio, y después de dos años de seguimiento. RESULTADOS: LA CORRECCIón, obtenida con el uso de VEPTR en el posoperatorio inmediato, fue en promedio 41,4% en relación a las radiografías iniciales sin tracción (p = 0,005 y 9,1% (p = 0

  7. Reed's Conjecture on hole expansions

    CERN Document Server

    Fouquet, Jean-Luc

    2012-01-01

    In 1998, Reed conjectured that for any graph $G$, $\\chi(G) \\leq \\lceil \\frac{\\omega(G) + \\Delta(G)+1}{2}\\rceil$, where $\\chi(G)$, $\\omega(G)$, and $\\Delta(G)$ respectively denote the chromatic number, the clique number and the maximum degree of $G$. In this paper, we study this conjecture for some {\\em expansions} of graphs, that is graphs obtained with the well known operation {\\em composition} of graphs. We prove that Reed's Conjecture holds for expansions of bipartite graphs, for expansions of odd holes where the minimum chromatic number of the components is even, when some component of the expansion has chromatic number 1 or when a component induces a bipartite graph. Moreover, Reed's Conjecture holds if all components have the same chromatic number, if the components have chromatic number at most 4 and when the odd hole has length 5. Finally, when $G$ is an odd hole expansion, we prove $\\chi(G)\\leq\\lceil\\frac{\\omega(G)+\\Delta(G)+1}{2}\\rceil+1$.

  8. Low thermal expansion glass ceramics

    CERN Document Server

    1995-01-01

    This book is one of a series reporting on international research and development activities conducted by the Schott group of companies With the series, Schott aims to provide an overview of its activities for scientists, engineers, and managers from all branches of industry worldwide where glasses and glass ceramics are of interest Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated This volume describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization Thus glass ceramics with thermal c...

  9. Low Thermal Expansion Glass Ceramics

    CERN Document Server

    Bach, Hans

    2005-01-01

    This book appears in the authoritative series reporting the international research and development activities conducted by the Schott group of companies. This series provides an overview of Schott's activities for scientists, engineers, and managers from all branches of industry worldwide in which glasses and glass ceramics are of interest. Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated. This new extended edition describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics. The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions. Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization. Thus g...

  10. Thermal Expansion of Hafnium Carbide

    Science.gov (United States)

    Grisaffe, Salvatore J.

    1960-01-01

    Since hafnium carbide (HfC) has a melting point of 7029 deg. F, it may have many high-temperature applications. A literature search uncovered very little information about the properties of HfC, and so a program was initiated at the Lewis Research Center to determine some of the physical properties of this material. This note presents the results of the thermal expansion investigation. The thermal-expansion measurements were made with a Gaertner dilatation interferometer calibrated to an accuracy of +/- 1 deg. F. This device indicates expansion by the movement of fringes produced by the cancellation and reinforcement of fixed wave-length light rays which are reflected from the surfaces of two parallel quartz glass disks. The test specimens which separate these disks are three small cones, each approximately 0.20 in. high.

  11. Repeated expansion in burn sequela.

    Science.gov (United States)

    Pitanguy, Ivo; Gontijo de Amorim, Natale Ferreira; Radwanski, Henrique N; Lintz, José Eduardo

    2002-08-01

    This paper presents a retrospective study of the use of 346 expanders in 132 patients operated at the Ivo Pitanguy Clinic, between the period of 1985 and 2000. The expanders were used in the treatment of burn sequela. In the majority of cases, more than one expander was used at the same time. In 42 patients, repeated tissue expansion was done. The re-expanded flaps demonstrated good distension and viability. With the increase in area at each new expansion, larger volume expanders were employed, achieving an adequate advancement of the flaps to remove the injured tissue. The great advantage of using tissue re-expansion in the burned patient is the reconstruction of extensive areas with the same color and texture of neighboring tissues, without the addition of new scars.

  12. 18 CFR 154.309 - Incremental expansions.

    Science.gov (United States)

    2010-04-01

    ... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Incremental expansions... incremental facilities to be rolled-in to the pipeline's rates. For every expansion that has an at-risk...

  13. Low-thermal expansion infrared glass ceramics

    Science.gov (United States)

    Lam, Philip

    2009-05-01

    L2 Tech, Inc. is in development of an innovative infrared-transparent glass ceramic material with low-thermal expansion (ZrW2O8) which has Negative Thermal Expansion (NTE). The glass phase is the infrared-transparent germanate glass which has positive thermal expansion (PTE). Then glass ceramic material has a balanced thermal expansion of near zero. The crystal structure is cubic and the thermal expansion of the glass ceramic is isotropic or equal in all directions.

  14. Expansive Openness in Teacher Practice

    Science.gov (United States)

    Kimmons, Royce

    2016-01-01

    Background/Context: Previous work on the use of open educational resources in K-12 classrooms has generally focused on issues related to cost. The current study takes a more expansive view of openness that also accounts for adaptation and sharing in authentic classroom contexts. Purpose/Objective/Research Question/Focus of Study The study seeks to…

  15. On Fourier re-expansions

    OpenAIRE

    Liflyand, E.

    2012-01-01

    We study an extension to Fourier transforms of the old problem on absolute convergence of the re-expansion in the sine (cosine) Fourier series of an absolutely convergent cosine (sine) Fourier series. The results are obtained by revealing certain relations between the Fourier transforms and their Hilbert transforms.

  16. On persistently positively expansive maps

    Directory of Open Access Journals (Sweden)

    Alexander Arbieto

    2010-06-01

    Full Text Available In this paper, we prove that any C¹-persistently positively expansive map is expanding. This improves a result due to Sakai (Sakai 2004.Neste artigo, mostramos que todo mapa C¹-persistentemente positivamente expansivo e expansor. Isto melhora um resultado devido a Sakai (Sakai 2004.

  17. The bootstrap and edgeworth expansion

    CERN Document Server

    Hall, Peter

    1992-01-01

    This monograph addresses two quite different topics, in the belief that each can shed light on the other. Firstly, it lays the foundation for a particular view of the bootstrap. Secondly, it gives an account of Edgeworth expansion. Chapter 1 is about the bootstrap, witih almost no mention of Edgeworth expansion; Chapter 2 is about Edgeworth expansion, with scarcely a word about the bootstrap; and Chapters 3 and 4 bring these two themes together, using Edgeworth expansion to explore and develop the properites of the bootstrap. The book is aimed a a graduate level audience who has some exposure to the methods of theoretical statistics. However, technical details are delayed until the last chapter (entitled "Details of Mathematical Rogour"), and so a mathematically able reader without knowledge of the rigorous theory of probability will have no trouble understanding the first four-fifths of the book. The book simultaneously fills two gaps in the literature; it provides a very readable graduate level account of t...

  18. Multiscale expansions in discrete world

    Indian Academy of Sciences (India)

    ... multiscale expansions discretely. The power of this manageable method is confirmed by applying it to two selected nonlinear Schrödinger evolution equations. This approach can also be applied to other nonlinear discrete evolution equations. All the computations have been made with Maple computer packet program.

  19. Large N Expansion. Vector Models

    OpenAIRE

    Nissimov, Emil; Pacheva, Svetlana

    2006-01-01

    Preliminary version of a contribution to the "Quantum Field Theory. Non-Perturbative QFT" topical area of "Modern Encyclopedia of Mathematical Physics" (SELECTA), eds. Aref'eva I, and Sternheimer D, Springer (2007). Consists of two parts - "main article" (Large N Expansion. Vector Models) and a "brief article" (BPHZL Renormalization).

  20. Effective Expansion: Balance between Shrinkage and Hygroscopic Expansion.

    Science.gov (United States)

    Suiter, E A; Watson, L E; Tantbirojn, D; Lou, J S B; Versluis, A

    2016-05-01

    The purpose of this study was to investigate the relationship between hygroscopic expansion and polymerization shrinkage for compensation of polymerization shrinkage stresses in a restored tooth. One resin-modified glass-ionomer (RMGI) (Ketac Nano, 3M ESPE), 2 compomers (Dyract, Dentsply; Compoglass, Ivoclar), and a universal resin-based composite (Esthet•X HD, Dentsply) were tested. Volumetric change after polymerization ("total shrinkage") and during 4 wk of water storage at 37°C was measured using an optical method (n= 10). Post-gel shrinkage was measured during polymerization using a strain gauge method (n= 10). Extracted human molars with large mesio-occluso-distal slot preparations were restored with the tested restorative materials. Tooth surfaces at baseline (preparation), after restoration, and during 4 wk of 37°C water storage were scanned with an optical scanner to determine cuspal flexure (n= 8). Occlusal interface integrity was measured using dye penetration. Data were analyzed using analysis of variance and post hoc tests (significance level 0.05). All tested materials shrunk after polymerization. RMGI had the highest total shrinkage (4.65%) but lowest post-gel shrinkage (0.35%). Shrinkage values dropped significantly during storage in water but had not completely compensated polymerization shrinkage after 4 wk. All restored teeth initially exhibited inward (negative) cuspal flexure due to polymerization shrinkage. Cuspal flexure with the RMGI restoration was significantly less (-6.4 µm) than with the other materials (-12.1 to -14.1 µm). After 1 d, cuspal flexure reversed to +5.0 µm cuspal expansion with the RMGI and increased to +9.3 µm at 4 wk. After 4 wk, hygroscopic expansion compensated cuspal flexure in a compomer (Compoglass) and reduced flexure with Dyract and resin-based composite. Marginal integrity (93.7% intact restoration wall) was best for the Compoglass restorations and lowest (73.1%) for the RMGI restorations. Hygroscopic

  1. Conteo de personas con un sensor RGBD comercial

    Directory of Open Access Journals (Sweden)

    M. Castrillón-Santan

    2014-07-01

    Full Text Available Resumen: En este trabajo se demuestra que la información de profundidad proporcionada por una cámara RGBD comercial de bajo coste, es una fuente fiable de datos para realizar de forma robusta el conteo automático de personas. La adopción de una configuración de vista cenital reduce la complejidad del problema, al mismo tiempo que permite preservar la privacidad de las personas moni- torizadas. Para llevar a cabo el estudio experimental se han considerado dos técnicas propias del campo de análisis de imágenes 2D trasladadas al contexto de imágenes de profundidad. Las pruebas evaluaron su rendimiento con v́ıdeos reales sin restricciones de iluminación, incluyendo episodios de iluminación cambiante o muy baja. En este conjunto experimental se realizó la detección, seguimiento y análisis de patrones de comportamiento de las personas que cruzaban el campo de visión. Los resultados obtenidos alcanzan una tasa de acierto próxima al 95%, superando los obtenidos con técnicas actuales basadas exclusivamente en información visual. Estos resultados sugieren la utilidad del uso de información de profundidad en esta tarea particular. Abstract: In this paper, we prove that depth information provided by a consumer depth camera is a reliable data source to perform ro- bust people counting. The adoption of a top view configuration reduces the space problem complexity for this task, while pre- serving privacy. Two different background subtraction approaches for color images are transferred to this context and tested in real video to perform detection, tracking, and behavioral pat- terns analysis of subjects crossing the field of view. The results achieved in an experimental setup with real video reported a TPR over 95%, beating robust GMM background subtraction based only on the visual cue. The results suggest the benefits of the depth cue for this particular task. Palabras clave: Conteo de personas, c

  2. con turbinas de disco con paletas planas

    Directory of Open Access Journals (Sweden)

    D. García-Cortés

    2006-01-01

    Full Text Available Las turbinas de disco con paletas planas son los impelentes de flujo radial más ampliamente utilizados en la industria por constituir el impelente que forma parte de la configuración geométrica estándar para obtener este patrón de flujo en los tanques agitados. El estudio detallado de la hidrodinámica en este sistema de agitación es fundamental para continuar obteniendo conocimientos básicos imprescindibles para la síntesis y la modelación matemática de diferentes procesos complejos que se llevan a cabo en los tanques agitados, por ejemplo, la cristalización esférica. El propósito de este artículo es hacer una revisión de la información publicada sobre la hidrodinámica y la modelación matemática de la dinámica de fluidos en los tanques agitados con turbinas de disco con paletas planas y señalar los avances logrados en cada uno de los aspectos abordados y aquellos en los cuales es necesario seguir investigando.

  3. Inversor Resonante de Tres Elementos L-LC con Caracteristica Cortocircuitable para Aplicaciones de Calentamiento por Induccion

    Science.gov (United States)

    Espi Huerta, Jose Miguel

    Los generadores de calentamiento por induccion son puentes inversores con carga resonante, cuya mision es basicamente crear una corriente sinusoidal de gran amplitud sobre la "bobina de caldeo", que forma parte del tanque resonante. En el interior de esta bobina se introduce la pieza que se desea calentar. EI campo magnetico creado induce corrientes superficiales (corrientes de Foucault) sobre la pieza, que producen su calentamiento. Los tanques resonantes (tambien llamados osciladores) utilizados en la actualidad son el resonante serie y el resonante paralelo. Aunque ya desde hace algun tiempo se vienen construyendo generadores de alta potencia basados en estos dos osciladores, el exito nunca ha. sido completo en ninguno de los dos casos. Tal y como se explica en la introduccion de esta memoria, los puentes inversores utilizados deben operar sobre una carga inductiva (corriente retrasada) para evitar el fenomeno de la recuperacion inversa de sus diodos y la consiguiente ruptura de los transistores. De la restriccion topologica anterior se deduce que el generador paralelo debe conmutar a frecuencias inferiores a la resonancia, y el serie a frecuencias superiores. A esta restriccion topologica hay que unir otra que es exclusiva del calentamiento por induccion: La corriente por la bobina de caldeo debe ser sinusoidal. De no ser asi, resultaria imposible disponer toda la potencia de calentamiento sobre la pieza en el espesor requerido por la aplicacion. Como consecuencia, los inversores no pueden operar por debajo de la frecuencia de resonancia del oscilador, pues en ese caso se amplifican los armonicos de orden superior de la tension/corriente de entrada situados sobre la resonancia, con la consiguiente distorsion de la corriente de salida. La conjuncion de las dos restricciones anteriores obligan al inversor paralelo a funcionar a la frecuencia de resonancia del oscilador. Esto imposibilita un control por variacion de frecuencia, regulandose la potencia desde la

  4. Shrub expansion in SW Greenland

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Halfdan

    , and has a range of ecosystem effects where it occurs. Shrub expansion has to a large extend been attributed to increasing temperatures over the past century, while grazing and human disturbance have received less attention. Alnus viridis ssp. crispa is a common arctic species that contributes...... including only undisturbed sites. Shrub cover increased most on E and SE facing slopes, in sites with stable substrate, in areas characterised by human disturbance and in areas without muskoxen grazing. Aspect and human disturbances had the strongest effect on shrub expansion, followed by muskoxen...... locations. A. viridis represents an interesting case to study these effects. SW Greenland is a subarctic to low-arctic region with only limited increases in temperatures during the past decades, and observed climate trends being largely dependent on the observation period. In this region there is limited...

  5. Shrub expansion in SW Greenland

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Halfdan

    of firewood collection. A delayed reaction to the ending of the little ice age cannot be excluded, but seems rather unlikely considering other studies from Greenland. Effects of global warming in SW Greenland must be studied over even longer time periods than the 120 years of the current study. To answer......, and has a range of ecosystem effects where it occurs. Shrub expansion has to a large extend been attributed to increasing temperatures over the past century, while grazing and human disturbance have received less attention. Alnus viridis ssp. crispa is a common arctic species that contributes...... by factors like grazing and human disturbance; II. which climatic factors control shrub growth in SW Greenland and whether these have improved sufficiently over the past century to allow shrub expansion; III. whether growth of A. viridis is promoted by experimental warming; IV. and whether plant genotypes...

  6. Videojuego con Realidad Virtual

    OpenAIRE

    González Mora, César

    2017-01-01

    El objetivo del proyecto es el desarrollo de un videojuego deportivo que utilice realidad mixta. El videojuego se podrá utilizar con dispositivos de tipo cardboard, y utilizará realidad aumentada para la interacción del jugador con el videojuego. En el desarrollo se utilizará el motor Unity para conseguir una aplicación multiplataforma, y la librería Vuforia para implementar realidad mixta.

  7. Sistemas integrados con Arduino

    OpenAIRE

    EL YAKOUTI, MOHAMMED

    2017-01-01

    Design of a robot prototype remotely controllable from Bluetooth using Arduino. Control and testing of sensors and events interacting with Arduino and Bluetooth. Diseño de un prototipo de robot controlable remotamente con Bluetooth utilizando Arduino. Control y verificación de los sensores y eventos que interactúan mediante el Arduino y el Bluetooth. El Yakouti, M. (2017). Sistemas integrados con Arduino. http://hdl.handle.net/10251/89274. TFGM

  8. RELIABILITY OF LENTICULAR EXPANSION COMPENSATORS

    Directory of Open Access Journals (Sweden)

    Gabriel BURLACU,

    2011-11-01

    Full Text Available Axial lenticular compensators are made to take over the longitudinal heat expansion, shock , vibration and noise, made elastic connections for piping systems. In order to have a long life for installations it is necessary that all elements, including lenticular compensators, have a good reliability. This desire can be did by technology of manufactoring and assembly of compensators, the material for lenses and by maintenance.of compensator

  9. Investigando con personas con dificultades de aprendizaje

    Directory of Open Access Journals (Sweden)

    Borja González Luna

    2013-12-01

    Full Text Available El artículo muestra los orígenes de lo que Walmsley (2008 denomina «investigación inclusiva». Para comprender qué se entiende por investigación inclusiva tenemos que remontarnos a los debates epistemológicos sobre las metodologías cuantitativas y cualitativas, acontecidos en la década de los 90, en torno a la revista Disability & Society. A partir de una síntesis de dichos debates, focalizados en el ámbito de la «discapacidad intelectual y del desarrollo», se exponen dos estrategias de colaboración con dicha población: a una aproximación etnográfica (de trabajo grupal, y b una aproximación biográfica (de trabajo individual. A continuación se esboza un posible diseño de trabajo de campo que intenta superar el paradigma cualitativo «clásico» con el objetivo de incluir a dicho colectivo más allá del rol de «sujetos de la investigación». Para finalizar se recoge el debate sobre la accesibilidad de los resultados de la investigación a los participantes en dichas investigaciones, y con ello la necesaria innovación en el ámbito de las «devoluciones» de los resultados, cuando se trata de incluir a personas que presentan limitaciones para la comprensión del lenguaje abstracto oral y/o escrito.

  10. Simplifying Bridge Expansion Joint Design and Maintenance

    Science.gov (United States)

    2011-10-19

    This report presents a study focused on identifying the most durable expansion joints for the South : Carolina Department of Transportation. This is performed by proposing a degradation model for the : expansion joints and updating it based on bridge...

  11. VALIDACIÓN DE UN ALGORITMO HÍBRIDO DEL PSO CON EL MÉTODO SIMPLEX Y DE TOPOLOGÍA DE EVOLUCIÓN PARAMÉTRICA

    Directory of Open Access Journals (Sweden)

    RODRIGO CORREA

    2011-01-01

    Full Text Available Este artículo describe algunos de los aspectos más importantes relacionados con la experimentación numérica de un híbrido del algoritmo PSO (Particle Swarm Optimization con el tradicional método simplex modificado de NelderMead. El híbrido de estas dos técnicas de optimización sin restricciones se realizó con una topología que permite optimizar en cada iteración los parámetros del algoritmo PSO utilizando el método simplex modificado. Se realizaron experimentos numéricos con este algoritmo híbrido aplicados a varias funciones de prueba típicas para establecer su efectividad. Los resultados obtenidos se compararon con los del método simplex y el método cuadrático, los cuales resultaron ser muy satisfactorios desde el punto de vista de su repetibilidad y reproducibilidad, aunque el tiempo de cómputo fue considerablemente mayor. Se resalta, sin embargo, que la precisión del algoritmo híbrido fue del cien por ciento en todos los ensayos para las funciones de prueba seleccionadas.

  12. Review: Algoritmos de planificación para la transmisión de datos en tiempo real con IEEE 802.15.4

    Directory of Open Access Journals (Sweden)

    Sixto Enrique Campaña Bastidas

    2015-10-01

    Full Text Available Las redes de sensores inalámbricas (WSN se están extendiendo a muchos campos de aplicación, tales como ciudades inteligentes, ambientes inteligentes, internet de las cosas, entre otras tecnologías. Para muchasde estas tendencias es esencial establecer métodos para la entrega de paquetes, sobre todo aquellos que presenten garantías de tiempo real. En este trabajo se presenta un estudio de los avances recientes publicadosen la literatura científica, considerando principalmente las técnicas de acceso al medio y la planificación de transmisión de datos con garantías de tiempo real en WSN basadas en el estándar IEEE 802.15.4. Este estudiopresenta las características más importantes, así como las principales diferencias entre las distintas técnicas. Al final se presentan algunas conclusiones y se proponen futuras líneas de investigación que buscan con interés la aplicación de WSN en ambientes con restricciones de tiempo real.

  13. Construcción, validación y confiabilidad de un cuestionario sobre niños y niñas con TDAH

    Directory of Open Access Journals (Sweden)

    Luisa Matilde Salamanca

    2010-10-01

    Full Text Available Objetivo: Diseñar, validar y determinar la confiabilidad de un instrumento para evaluar limitaciones y restricciones de niños y niñas con TDAH. Procedimiento: Determiné la validez del contenido y apariencia por juicio de expertos y expertas, y la consistencia interna mediante alfa de Cronbach, de una muestra de 42 padres y madres de niños y niñas de 6 a 12 años con TDAH. Resultados: Diseñé el cuestionario CLARPTDAH Padres con 7 dominios y 39 ítems, buena validez de apariencia y contenido y consistencia interna por alfa de Cronbach de 0.74. Conclusiones: El uso de la Clasificación Internacional del Funcionamiento, la Discapacidad y la Salud en el TDAH trasciende los signos a otras alteraciones y al funcionamiento de los niños y niñas. Es necesario continuar procesos de validación y confiabilidad del cuestionario.

  14. Construcción, validación y confiabilidad de un cuestionario sobre niños y niñas con TDAH

    Directory of Open Access Journals (Sweden)

    Luisa Matilde Salamanca

    2010-01-01

    Full Text Available Objetivo: Diseñar, validar y determinar la confiabilidad de un instrumento para evaluar limitaciones y restricciones de niños y niñas con TDAH. Procedimiento: Determiné la validez del contenido y apariencia por juicio de expertos y expertas, y la consistencia interna mediante alfa de Cronbach, de una muestra de 42 padres y madres de niños y niñas de 6 a 12 años con TDAH. Resultados: Diseñé el cuestionario CLARPTDAH Padres con 7 dominios y 39 ítems, buena validez de apariencia y contenido y consistencia interna por alfa de Cronbach de 0.74. Conclusiones: El uso de la Clasificación Internacional del Funcionamiento, la Discapacidad y la Salud en el TDAH trasciende los signos a otras alteraciones y al funcionamiento de los niños y niñas. Es necesario continuar procesos de validación y confiabilidad del cuestionario.

  15. 48 CFR 570.403 - Expansion requests.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Expansion requests. 570.403 Section 570.403 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION SPECIAL... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope...

  16. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  17. Contribution of thermal expansion and

    Directory of Open Access Journals (Sweden)

    O.I.Pursky

    2007-01-01

    Full Text Available A theoretical model is developed to describe the experimental results obtained for the isobaric thermal conductivity of rare gas solids (RGS. The isobaric thermal conductivity of RGS has been analysed within Debye approximation with regard to the effect of thermal expansion. The suggested model takes into consideration the fact that thermal conductivity is determined by U-processes while above the phonon mobility edge it is determined by "diffusive" modes migrating randomly from site to site. The mobility edge ω0 is determined from the condition that the phonon mean-free path restricted by the U-processes cannot be smaller than half of the phonon wavelength.

  18. Gravitational entropy of cosmic expansion

    CERN Document Server

    Sussman, Roberto A

    2014-01-01

    We apply a recent proposal to define "gravitational entropy" to the expansion of cosmic voids within the framework of non-perturbative General Relativity. By considering CDM void configurations compatible with basic observational constraints, we show that this entropy grows from post-inflationary conditions towards a final asymptotic value in a late time fully non-linear regime described by the Lemaitre-Tolman-Bondi (LTB) dust models. A qualitatively analogous behavior occurs if we assume a positive cosmological constant consistent with a $\\Lambda$-CDM background model. However, the $\\Lambda$ term introduces a significant suppression of entropy growth with the terminal equilibrium value reached at a much faster rate.

  19. Cerrejon expansion in a tight market?

    Energy Technology Data Exchange (ETDEWEB)

    Pretelt, A. [Carbocol SA, Bogota (Colombia)

    1995-12-31

    Examines plans to expand Carbocol`s Cerrejon North Zone coal mine (Colombia). Covers: background; current status of the project; main features of the expansion (i.e. coal reserves, infrastructure, operating costs, expansion schedule and market factors); advantages of expansion; and Carbocol`s vision of the market. A positive decision to expand will depend on the results of a feasibility class III study which will define in exact terms the technical and economic aspects of the expansion and the best way to execute it. The study will be completed next year. The expansion programme should improve the profitability of the project. 10 figs.

  20. Giochiamo con i robot

    Directory of Open Access Journals (Sweden)

    Andrea Bonarini

    2009-01-01

    Full Text Available "Giochiamo con i robot" e' un laboratorio interattivo per grandi e piccini realizzato per l'edizione 2007 del Festival della Scienza di Genova. Lungo un percorso che va dalla telerobotica alla robotica evolutiva, il laboratorio sviluppa il tema di dare intelligenza ai robot. Questo percorso, le cui tappe sono le varie installazioni, si conclude nella "bottega" dove e' possibile costruire e programmare i propri robot o smontare e modificare quelli esposti durante il percorso didattico. I visitatori sono coinvolti in attivita' ludiche grazie alle quali possonoentrare in contatto con alcune delle idee potenti della robotica,

  1. Pensar con las manos

    OpenAIRE

    Campo Baeza, Alberto

    2009-01-01

    Cuántas veces habré repetido este hermoso poema de Blake a mis alumnos tratando de inculcarles cuánto de inefable tiene la mejor Arquitectura. "To see a World in a grain of sand" tiene bastante que ver con lo que es un pequeño dibujo en relación con el proyecto que es capaz de explicarnos. Si el diccionario dice que diagrama es la "figura gráfica que explica un fenómeno determinado", sabiendo que la arquitectura construida es tan compleja, nos sorprende la capacidad de un diagrama, un p...

  2. El efecto de la evaluación del desempeño para alcanzar el rendimiento deseado: un estudio de caso en el hospital santa marta en Samacá-Boyacá. Colombia - enfoque a teoría de restricciones - armonía del ambiente laboral

    OpenAIRE

    Plata Castillo, Nury Lorena

    2014-01-01

    Este trabajo se centró en enfocar, El efecto de la Evaluación del desempeño para alcanzar el rendimiento deseado, aplicado a Teoría de Restricciones (TOC) encaminándolo a una profundización desde la mirada que permite TOC para la solución de problemas identificando los efectos indeseables del sistema, reconociendo el impacto de la evaluación del desempeño y proponiendo la solución para el mejoramiento a través de la comprensión del problema y diseño de estrategias para el cambio y alcanzar la...

  3. Imagination as expansion of experience.

    Science.gov (United States)

    Zittoun, Tania; Cerchia, Frédéric

    2013-09-01

    This paper proposes a developmental view on imagination: from this perspective, imagination can be seen as triggered by some disrupting event, which generates a disjunction from the person's unfolding experience of the "real" world, and as unfolding as a loop, which eventually comes back to the actual experience. Examining recent and classical theorization of imagination in psychology, the paper opposes a deficitary view of imagination to an expansive notion of imagination. The paper explores Piaget, Vygotsky, Harris and Pelaprat & Cole consider: 1) What does provoke a "rupture" or disjunction? 2) What are the psychological processes involved in the imaginary loop? 3) What nourishes such processes? 4) What are the consequences of such imaginary loop, or what does it enable doing? The paper proposes to adopt an expansive view of imagination, as Vygotsky proposed-a perspective that has been under-explored empirically since his seminal work. To stimulate such sociocultural psychology of imagination, two empirical examples are provided, one showing how children make sense of metaphor in an experimental setting, the other showing a young person using a novel met at school as symbolic resource.

  4. Fast algorithms for Quadrature by Expansion I: Globally valid expansions

    Science.gov (United States)

    Rachh, Manas; Klöckner, Andreas; O'Neil, Michael

    2017-09-01

    The use of integral equation methods for the efficient numerical solution of PDE boundary value problems requires two main tools: quadrature rules for the evaluation of layer potential integral operators with singular kernels, and fast algorithms for solving the resulting dense linear systems. Classically, these tools were developed separately. In this work, we present a unified numerical scheme based on coupling Quadrature by Expansion, a recent quadrature method, to a customized Fast Multipole Method (FMM) for the Helmholtz equation in two dimensions. The method allows the evaluation of layer potentials in linear-time complexity, anywhere in space, with a uniform, user-chosen level of accuracy as a black-box computational method. Providing this capability requires geometric and algorithmic considerations beyond the needs of standard FMMs as well as careful consideration of the accuracy of multipole translations. We illustrate the speed and accuracy of our method with various numerical examples.

  5. fertilizada con diferentes abonos

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Elizondo-Salazar

    2007-01-01

    Full Text Available Producción y calidad de la biomasa de morera (Morus alba fertilizada con diferentes abonos. Se llevó a cabo un experimento en la Estación Experimental “Alfredo Volio Mata” de la Universidad de Costa Rica con el fi n de evaluar la aplicación de 150 kg de N/ha/año proveniente de dos abonos orgánicos: lombriabono y compostaje; y de un fertilizante químico, sobre la producción y calidad de la biomasa de morera. El periodo experimental comprendió un ciclo de 12 meses, iniciando en julio del 2003 y fi nalizando en julio del 2004. Se utilizó una plantación de morera de 12 años de establecida con una densidad de siembra de 27.777 plantas/ ha. Se empleó un diseño de bloques completos al azar con cuatro tratamientos: dos abonos orgánicos, nitrato de amonio (33,5% N y un control. Las plantas se podaron a 0,6 m sobre el nivel del suelo al inicio del ensayo. Durante el periodo experimental, las plantas fueron podadas consecutivamente cada 90 días. Las hojas y los tallos fueron separados y analizados para determinar el contenido de materia seca y proteína cruda. La producción de materia seca fue 23% superior y el contenido de proteína cruda fue signifi cativamente mayor con el nitrógeno químico, mientras que el contenido de materia seca fue menor. No se encontraron diferencias signifi cativas entre el tratamiento control y los tratamientos orgánicos.

  6. On the equisummability of Hermite and Fourier expansions

    Indian Academy of Sciences (India)

    We prove an equisummability result for the Fourier expansions and Hermite expansions as well as special Hermite expansions. We also prove the uniform boundedness of the Bochner-Riesz means associated to the Hermite expansions for polyradial functions.

  7. Dualidad de las funciones de costo y de producción en sus formas homotética y no homotética con aplicación de transformadas de Lagrange

    Directory of Open Access Journals (Sweden)

    Giovanni E. Reyes

    2006-01-01

    Full Text Available Este escrito estudia las funciones tanto de producción como de costos, no solamente en sí misma, sino lo que es más importante, en términos de sus mutas transformaciones, cuando las condiciones de cálculo pueden ser particularmente difíciles o complicadas. Es un tópico relacionado con la teoría de producción la que se presenta más allá de las formas tradicionales, de abordar las funciones de costo y producción por separado. Es un tema que pertenece a los aspectos fundamentales de gestión de cualquier empresa. En este estudio, utilicé las formas homotéticas y no homotéticas de las funciones, finalizando el escrito con aplicaciones derivadas del método de transformadas de Lagrange, con el fin de maximizar resultados a partir de factores específicos que tienen restricciones, tales como aquellas relacionadas con límites en el presupuesto.

  8. Relationship Development in Greenfield Expansions

    DEFF Research Database (Denmark)

    Drogendijk, Rian; Andersson, Ulf

    2013-01-01

    This paper investigates conceptually how new Greenfield subsidiaries develop relationships over time. We focus our analysis on the earliest start-up stage of new Greenfield subsidiaries, and on the dynamics of relationships development with five different groups of actors within the MNC...... and the local environment of the new Greenfield. We argue that relationship strength, or the intensity of interaction and resource exchange, depends on the new Greenfield''s degree of dependence or interdependence within these relationships and develop propositions based on institutional theory, resource...... dependency theory and network approaches. In the concluding sections we suggest directions for future work to enhance understanding of the dynamics of relationship management in new Greenfield expansions....

  9. Expansion of Physician Assistant Education.

    Science.gov (United States)

    Cawley, James F; Jones, P. Eugene; Miller, Anthony A; Orcutt, Venetia L

    2016-12-01

    Physician assistant (PA) educational programs were created in the 1960s to prepare a new type of health care practitioner. Physician assistant programs began as experiments in medical education, and later, they proved to be highly successful in preparing capable, flexible, and productive clinicians. The growth of PA educational programs in US medical education-stimulated by grants, public policy, and anticipated shortages of providers-has gone through 3 distinct phases. At present, such programs are in the midst of the third growth spurt that is expected to continue beyond 2020, as a large number of colleges and universities seek to sponsor PA programs and attain accreditation status. Characteristics of these new programs are described, and the implications of the current expansion of PA education are examined.

  10. Serial Tissue Expansion at the Same Site in Pediatric Patients: Is the Subsequent Expansion Faster?

    Directory of Open Access Journals (Sweden)

    Moon Ki Lee

    2017-11-01

    Full Text Available Background Serial tissue expansion is performed to remove giant congenital melanocytic nevi. However, there have been no studies comparing the expansion rate between the subsequent and preceding expansions. In this study, we analyzed the rate of expansion in accordance with the number of surgeries, expander location, expander size, and sex. Methods A retrospective analysis was performed in pediatric patients who underwent tissue expansion for giant congenital melanocytic nevi. We tested four factors that may influence the expansion rate: The number of surgeries, expander location, expander size, and sex. The rate of expansion was calculated by dividing the ‘inflation amount’ by the ‘expander size’. Results The expansion rate, compared with the first-time group, was 1.25 times higher in the second-or-more group (P=0.04 and 1.84 times higher in the third-or-more group (P<0.01. The expansion rate was higher at the trunk than at other sites (P<0.01. There was a tendency of lower expansion rate for larger expanders (P=0.03. Sex did not affect the expansion rate. Conclusions There was a positive correlation between the number of surgeries and the expansion rate, a positive correlation between the expander location and the expansion rate, and a negative correlation between the expander size and the expansion rate.

  11. Pressurized electrolysis stack with thermal expansion capability

    Science.gov (United States)

    Bourgeois, Richard Scott

    2015-07-14

    The present techniques provide systems and methods for mounting an electrolyzer stack in an outer shell so as to allow for differential thermal expansion of the electrolyzer stack and shell. Generally, an electrolyzer stack may be formed from a material with a high coefficient of thermal expansion, while the shell may be formed from a material having a lower coefficient of thermal expansion. The differences between the coefficients of thermal expansion may lead to damage to the electrolyzer stack as the shell may restrain the thermal expansion of the electrolyzer stack. To allow for the differences in thermal expansion, the electrolyzer stack may be mounted within the shell leaving a space between the electrolyzer stack and shell. The space between the electrolyzer stack and the shell may be filled with a non-conductive fluid to further equalize pressure inside and outside of the electrolyzer stack.

  12. Aspectos relevantes en la rehabilitación de los niños con enfermedades neuromusculares

    Directory of Open Access Journals (Sweden)

    V. Rebeca Valdebenito, Dra.

    2014-03-01

    Full Text Available Las Enfermedades Neuromusculares representan un grupo heterogéneo de trastornos que incluyen alteraciones en la motoneurona, nervios periféricos, transmisión neuromuscular y las patologías que afectan al músculo propiamente tal. Su progresión varía considerablemente presentando diversos déficits que pueden variar desde la debilidad muscular, pérdida sensorial, dolor, fatiga y la disfunción autonómica, los que se combinan para dar lugar al daño músculo-esquelético generando limitaciones en las actividades de la vida diaria y restricciones en la participación. Es por esto, que en las últimas décadas se han creado programas de rehabilitación integrados por un equipo multidisciplinario, que trabajan de manera coordinada, abarcando todos los factores que producen y aumentan la discapacidad realizando el control, la prevención y el tratamiento de las complicaciones que derivan durante la evolución de este grupo de enfermedades, con el objetivo de lograr la mayor integración que el estadio de su enfermedad pueda permitir.

  13. Fundamentals of Thermal Expansion and Thermal Contraction

    OpenAIRE

    Liu, Zi-Kui; Shang, Shun-Li; Wang, Yi

    2017-01-01

    Thermal expansion is an important property of substances. Its theoretical prediction has been challenging, particularly in cases the volume decreases with temperature, i.e., thermal contraction or negative thermal expansion at high temperatures. In this paper, a new theory recently developed by the authors has been reviewed and further examined in the framework of fundamental thermodynamics and statistical mechanics. Its applications to cerium with colossal thermal expansion and Fe3Pt with th...

  14. pacientes con falla cardiaca

    Directory of Open Access Journals (Sweden)

    Diana Marcela Achury Saldaña

    2007-01-01

    Full Text Available Objetivo: determinar la adherencia al tratamiento de pacientes con falla cardiaca hospitalizados, al aplicar un plan educativo quefomenta el autocuidado.Método: estudio cuasiexperimental (entrevistas enfermera-paciente realizado entre diciembre de 2004 y mayo de 2006, con unamuestra de 50 pacientes seleccionados por conveniencia. Se diseñó un instrumento para evaluar los comportamientos de los pacientes,con base en algunos resultados de la adherencia y sus respectivos indicadores de la taxonomía NOC (Nursing out comes classification. Laadherencia al tratamiento fue medida en dos momentos: el primero durante la hospitalización, seguido de la aplicación del plan educativoantes del alta, que proporcionaba información en el manejo de su enfermedad desde una dimensión física, psicológica y social quepromueve el autocuidado; y el segundo un mes después del alta en su domicilio.Resultados: diferencias estadísticamente significativas (P=0,0001 que demuestran cómo mediante la capacitación al paciente enel manejo de su tratamiento farmacológico y no farmacológico, el establecimiento de una sana relación entre el profesional de enfermeríay el paciente, y la participación de la familia, se logra una total adherencia al tratamiento.Conclusiones: para lograr una adherencia total del paciente con falla cardiaca al tratamiento es necesario un proceso educativo y unseguimiento continuo y personalizado que motive permanentemente al paciente y se le reconozca el papel protagónico en su cuidado y manejo de la enfermedad.

  15. Encuentros con Elena Poniatowska

    OpenAIRE

    Uzquiza González, José Ignacio

    2008-01-01

    El autor analiza, desde su encuentro con Elena Poniatowska, la vertiente de la literatura testimonial como literatura de mujeres. Un análisis interior de la relación entre realidad y ficción, entre Elena, Jesusa o Tinísima. The author analyzes testimonial literature from the perspective of female literature through his meeting with Elena Poniatowska. An analysis of reality vs. Fiction in Elena, Jesusa and Tinisima.

  16. Lectura con adolescentes

    Directory of Open Access Journals (Sweden)

    Silvia Méndez Anchía

    2007-01-01

    Full Text Available Con base en la premisa de que la lectura de textos literarios tiene una función formadora y que esta se acentúa en la adolescencia, me propongo demostrar que el cuento “Rapunzel” puede utilizarse como estrategia para explorar algunas situaciones que los sujetos adolescentes perciben como particulares en relación con su vida, pero que se inscriben dentro de grandes problemáticas estudiadas por varias disciplinas. Para ello, he identificado, desde dos marcos de referencia (sociológico y psicoanalítico, diversas problemáticas y discursos que se desprenden de la lectura del cuento realizada por dos mujeres adolescentes, quienes respondieron una guía de lectura y participaron en una entrevista a profundidad. Concluyo que la lectura y comentario del cuento hacen posible que una serie de experiencias que los sujetos adolescentes viven como únicas (como el embarazo de una amiga, las críticas de las personas adultas y las exigencias de padres y madres, ingresen en el circuito de los conocimientos generales al relacionarlas con los discursos y problemáticas en que se inscriben (por ejemplo, el discurso de la “crisis” de la adolescencia, el enfoque de derechos humanos, el mundo fantasmático materno. Por ello, recomiendo la lectura y comentario de textos literarios como estrategia didáctica para contribuir a la elaboración de la subjetividad de personas adolescentes.

  17. Structure and thermal expansion of liquid bismuth

    Directory of Open Access Journals (Sweden)

    Mudry S.

    2015-12-01

    Full Text Available Experimental structural data for liquid Bi were used for estimation of the main structure parameters as well as the thermal expansion coefficient both in supercooled and superheated temperature ranges. It was shown that the equilibrium melt had a positive thermal expansion coefficient within a temperature range upon melting and a negative one at higher temperatures. The former was related to structure changes upon melting, whereas the latter with topologic disordering upon further heating. It was found that the superheated melt had a negative thermal expansion coefficient. The results obtained from structural data were compared with the thermal expansion coefficient calculated from the data of density for liquid Bi.

  18. Thermal expansion of L-ascorbic acid

    Science.gov (United States)

    Nicolaï, B.; Barrio, M.; Tamarit, J.-Ll.; Céolin, R.; Rietveld, I. B.

    2017-04-01

    The specific volume of vitamin C has been investigated by X-ray powder diffraction as a function of temperature from 110 K up to complete degradation around 440 K. Its thermal expansion is relatively small in comparison with other organic compounds with an expansivity α v of 1.2(3) × 10-4 K-1. The structure consists of strongly bound molecules in the ac plane through a dense network of hydrogen bonds. The thermal expansion is anisotropic. Along the b axis, the expansion has most leeway and is about 10 times larger than in the other directions.

  19. Desarrollo de un modelo generalizado para realimentación de fuerza y torque en cirugía cardiotorácica robótica mínimamente invasiva: determinación de condiciones y restricciones

    Directory of Open Access Journals (Sweden)

    Vera Pérez, IEE., PhD.(c

    2011-07-01

    Conclusiones: Las condiciones relacionadas con la incorporación de un sensor de fuerza y la percepción del cirujano en cuanto al tacto y la fuerza aplicada, resultan ser importantes en procedimientos de MICS robótica y requiere la inclusión de un sistema de control que permita la optimización de procedimientos por telepresencia.

  20. Primordial vorticity and gradient expansion

    CERN Document Server

    Giovannini, Massimo

    2012-01-01

    The evolution equations of the vorticities of the electrons, ions and photons in a pre-decoupling plasma are derived, in a fully inhomogeneous geometry, by combining the general relativistic gradient expansion and the drift approximation within the Adler-Misner-Deser decomposition. The vorticity transfer between the different species is discussed in this novel framework and a set of general conservation laws, connecting the vorticities of the three-component plasma with the magnetic field intensity, is derived. After demonstrating that a source of large-scale vorticity resides in the spatial gradients of the geometry and of the electromagnetic sources, the total vorticity is estimated to lowest order in the spatial gradients and by enforcing the validity of the momentum constraint. By acknowledging the current bounds on the tensor to scalar ratio in the (minimal) tensor extension of the $\\Lambda$CDM paradigm the maximal comoving magnetic field induced by the total vorticity turns out to be, at most, of the or...

  1. Local expansions and accretive mappings

    Directory of Open Access Journals (Sweden)

    W. A. Kirk

    1983-01-01

    Full Text Available Let X and Y be complete metric spaces with Y metrically convex, let D⊂X be open, fix u0∈X, and let d(u=d(u0,u for all u∈D. Let f:X→2Y be a closed mapping which maps open subsets of D onto open sets in Y, and suppose f is locally expansive on D in the sense that there exists a continuous nonincreasing function c:R+→R+ with ∫+∞c(sds=+∞ such that each point x∈D has a neighborhood N for which dist(f(u,f(v≥c(max{d(u,d(v}d(u,v for all u,v∈N. Then, given y∈Y, it is shown that y∈f(D iff there exists x0∈D such that for x∈X\\D, dist(y,f(x0≤dist(u,f(x. This result is then applied to the study of existence of zeros of (set-valued locally strongly accretive and ϕ-accretive mappings in Banach spaces

  2. Earnings Returns to the British Education Expansion

    Science.gov (United States)

    Devereux, Paul J.; Fan, Wen

    2011-01-01

    We study the effects of the large expansion in British educational attainment that took place for cohorts born between 1970 and 1975. Using the Quarterly Labour Force Survey, we find that the expansion caused men to increase education by about a year on average and gain about 8% higher wages; women obtained a slightly greater increase in education…

  3. Series expansion of the modified Einstein Procedure

    Science.gov (United States)

    Seema Chandrakant Shah-Fairbank

    2009-01-01

    This study examines calculating total sediment discharge based on the Modified Einstein Procedure (MEP). A new procedure based on the Series Expansion of the Modified Einstein Procedure (SEMEP) has been developed. This procedure contains four main modifications to MEP. First, SEMEP solves the Einstein integrals quickly and accurately based on a series expansion. Next,...

  4. Virial expansion coefficients in the harmonic approximation

    DEFF Research Database (Denmark)

    R. Armstrong, J.; Zinner, Nikolaj Thomas; V. Fedorov, D.

    2012-01-01

    The virial expansion method is applied within a harmonic approximation to an interacting N-body system of identical fermions. We compute the canonical partition functions for two and three particles to get the two lowest orders in the expansion. The energy spectrum is carefully interpolated...

  5. Platform Expansion Design as Strategic Choice

    DEFF Research Database (Denmark)

    Staykova, Kalina S.; Damsgaard, Jan

    2016-01-01

    In this paper, we address how the strategic choice of platform expansion design impacts the subse-quent platform strategy. We identify two distinct approaches to platform expansion – platform bun-dling and platform constellations, which currently co-exist. The purpose of this paper is to outline...

  6. The heavy quark expansion of QCD

    Energy Technology Data Exchange (ETDEWEB)

    Falk, A.F. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy

    1997-06-01

    These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic B decays are included. Heavy hadron production via nonperturbative fragmentation processes is also discussed. 54 refs., 7 figs.

  7. Expansion techniques for collisionless stellar dynamical simulations

    Energy Technology Data Exchange (ETDEWEB)

    Meiron, Yohai [Kavli Institute for Astronomy and Astrophysics at Peking University, Beijing 100871 (China); Li, Baile; Holley-Bockelmann, Kelly [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 (United States); Spurzem, Rainer, E-mail: ymeiron@pku.edu.cn [National Astronomical Observatories of China, Chinese Academy of Sciences, Beijing 100012 (China)

    2014-09-10

    We present graphics processing unit (GPU) implementations of two fast force calculation methods based on series expansions of the Poisson equation. One method is the self-consistent field (SCF) method, which is a Fourier-like expansion of the density field in some basis set; the other method is the multipole expansion (MEX) method, which is a Taylor-like expansion of the Green's function. MEX, which has been advocated in the past, has not gained as much popularity as SCF. Both are particle-field methods and optimized for collisionless galactic dynamics, but while SCF is a 'pure' expansion, MEX is an expansion in just the angular part; thus, MEX is capable of capturing radial structure easily, while SCF needs a large number of radial terms. We show that despite the expansion bias, these methods are more accurate than direct techniques for the same number of particles. The performance of our GPU code, which we call ETICS, is profiled and compared to a CPU implementation. On the tested GPU hardware, a full force calculation for one million particles took ∼0.1 s (depending on expansion cutoff), making simulations with as many as 10{sup 8} particles fast for a comparatively small number of nodes.

  8. Arquitectura con discurso

    OpenAIRE

    Schaposnik, Viviana

    2001-01-01

    En particular a la Carrera Arquitectura le compete un doble rol social: uno general, "educar" desde la Universidad y otro, específico, el que le es propio: dar respuesta a las necesidades planteadas por la sociedad haciéndole su lugar: construyéndolo junto con ella. Aparece la figura del "alumno de arquitectura"' nuestro destinatario específico. El alumno de arquitectura, también deberá tomar conciencia, entender, que el "espacio" que él deberá dominar a través d...

  9. Mayonesa con quitosano

    OpenAIRE

    Gaffrey, María Celeste

    2014-01-01

    Introducción: El quitosano es un polímero natural que se obtiene a partir de la quitina, la cual forma parte de la estructura de soporte de numerosos organismos vivos, tales como artrópodos (crustáceos e insectos), moluscos y hongos. Presenta propiedades aplicables en los alimentos, como estabilizante, emulsificante, y quelante. No puede ser digerido por los seres humanos por lo cual está considerado como una fibra dietética con un contenido calórico cero. Objetivos: Evaluar...

  10. Eugenistas, pero con prudencia

    Directory of Open Access Journals (Sweden)

    Pogliano, Claudio

    1999-12-01

    Full Text Available Thinking that one could not describe eugenics like a unique movement, since numerous bound varians took place related to the geographical and cultural context, this article tries to demostrate the peculiarity of the Italian case. If already in 1889 Giuseppe Sergi wanted that the artificial selection take it to end what should make the natural, avoiding the risk of the so called «degeneration», only in the face of the First World War seems to grow the alarm for the decadent quality of the population, finding a more and more wide echo. In 1919 the Siges was born (Società italiana de genetica ed eugenica shocked under the impression of the difusse fear about the butcher the war had caused. From there from now on fastens a «nazional» direction closely related to the traditional thought and also with the new political temper. A «moderate» direction, Fascist, Catholic, that was built in consonance with the pronatalism of the regime and in rough polemic with the presumed Anglo-Saxon eugenics aberration.

    Partiendo de la base de que no se puede describir la eugénica como un movimiento unitario, ya que se produjeron numerosas variantes ligadas al contexto geográfico y cultural, este artículo intenta demostrar la peculiaridad del caso italiano. Si ya en 1889 Giuseppe Sergi deseaba que la selección artificial llevase a cabo lo que debía de hacer la natural, evitando así el riesgo de la «degeneración », sólo ante la Primera Guerra Mundial parece crecer la alarma por la decadente calidad de la población, encontrando un eco cada vez más amplio. En 1919 nació la Sige (Società italiana de genetica ed eugenica bajo la impresión del difuso temor que la carnicería bélica había provocado. De ahí en adelante prende rápidamente una dirección «nazional» que se imbrica tanto con una tradición del pensamiento como con el nuevo temple político. Una dirección «moderada» fascista, católica, que se construyó en consonancia con el

  11. ABS dopado con grafeno

    OpenAIRE

    Gago Velasco, Israel; Ibarra Berrocal, Isidro Jesús; León Albert, Gerardo; Miguel Hernández, Beatriz

    2016-01-01

    Número de publicación: 2570391 Número de solicitud: 201630046 La presente invención se refiere a un procedimiento para la preparación de un polímero de ABS (acrilonitrilo-butadieno-estireno) dopado con grafeno que comprende dispersar el grafeno en un disolvente, adicionar a la dispersión anterior el ABS, reflujo de la dispersión la etapa anterior y evaporación del disolvente para obtener un gel. La presente invención se refiere también al polímero obtenido por dicho procedimiento. U...

  12. Business information query expansion through semantic network

    Science.gov (United States)

    Gong, Zhiguo; Muyeba, Maybin; Guo, Jingzhi

    2010-02-01

    In this article, we propose a method for business information query expansions. In our approach, hypernym/hyponymy and synonym relations in WordNet are used as the basic expansion rules. Then we use WordNet Lexical Chains and WordNet semantic similarity to assign terms in the same query into different groups with respect to their semantic similarities. For each group, we expand the highest terms in the WordNet hierarchies with hypernym and synonym, the lowest terms with hyponym and synonym and all other terms with only synonym. In this way, the contradictory caused by full expansion can be well controlled. Furthermore, we use collection-related term semantic network to further improve the expansion performance. And our experiment reveals that our solution for query expansion can improve the query performance dramatically.

  13. Maxwell superalgebras and Abelian semigroup expansion

    Directory of Open Access Journals (Sweden)

    P.K. Concha

    2014-09-01

    Full Text Available The Abelian semigroup expansion is a powerful and simple method to derive new Lie algebras from a given one. Recently it was shown that the S-expansion of so(3,2 leads us to the Maxwell algebra M. In this paper we extend this result to superalgebras, by proving that different choices of abelian semigroups S lead to interesting D=4 Maxwell Superalgebras. In particular, the minimal Maxwell superalgebra sM and the N-extended Maxwell superalgebra sM(N recently found by the Maurer–Cartan expansion procedure, are derived alternatively as an S-expansion of osp(4|N. Moreover, we show that new minimal Maxwell superalgebras type sMm+2 and their N-extended generalization can be obtained using the S-expansion procedure.

  14. Entrevista con Giovanni Levi

    Directory of Open Access Journals (Sweden)

    Monica Oliveira

    2017-06-01

    Full Text Available En esta entrevista, Giovanni Levi - como un conocedor del tema de Familia - realiza una importante evaluación sobre el actual estado de las investigaciones realizadas en el Brasil y em el exterior. Con estilo franco, agudo y lucido critica las visiones tradicionales y sus ilusiones ypropone nuevos conceptos y métodos. La historia de la familia debería ceder espacio para el estudio de las redes relacionales o de los mundos relacionales. De la misma forma, la historia cuantitativa debería abrir espacio para el estudio de las cualidades. Ya con relación a la historia de las elites, tan estudiada y reproducida en una diversidad de trabajos, que deberíase mirar en otra perspectiva. Es decir, no mirar a las reglas sociales predeterminadas, sino a los desvíos y a las variaciones. Levi defiende que los historiadores deben trascender a los documentos que se encuentran fácilmente y que pueden fortalecer perspectivas deformadas y esequilibradas de la sociedad. Para él, los historiadores deben esforzarse por estudiar a aquellos grupos que dejaron pocos rastros documentales. En ese esfuerzo existiría una nueva mirada sobre la historia de la familia.

  15. Entrevista con Patricia Ariza

    Directory of Open Access Journals (Sweden)

    Esperanza Londoño La Rotta

    2017-01-01

    Full Text Available Pensamiento, Palabra y Obra entrevista a una artista, feminista y activista política, quien como mujer y artista ha permitido pensar el arte más allá de un simple espectáculo. Toda una vida dedicada al teatro y a darle voz, a través de sus obras, a víctimas del conflicto colombiano, defensora de derechos humanos; además de hacer evidente en su vida y a través de la plataforma “Artistas por la paz”, las múltiples relaciones que se pueden establecer entre el arte, la construcción de paz y la resolución de conflictos. Hablamos en su casa, en medio del calor de la bienvenida con Patricia Ariza, directora del festival alternativo de teatro, de Mujeres en Escena y de la Corporación Colombiana de Teatro, entre otras muchas actividades que voluntariamente su espíritu libertario ha asumido. Esta entrevista se realizó antes del 2 de octubre, pero con la revisión de los acuerdos que propició el plebiscito ganado por una ínfima minoría por el no, sigue siendo vigente este planteamiento.

  16. Giant negative thermal expansion in magnetic nanocrystals

    Science.gov (United States)

    Zheng, X. G.; Kubozono, H.; Yamada, H.; Kato, K.; Ishiwata, Y.; Xu, C. N.

    2008-12-01

    Most solids expand when they are heated, but a property known as negative thermal expansion has been observed in a number of materials, including the oxide ZrW2O8 (ref. 1) and the framework material ZnxCd1-x(CN)2 (refs 2,3). This unusual behaviour can be understood in terms of low-energy phonons, while the colossal values of both positive and negative thermal expansion recently observed in another framework material, Ag3[Co(CN)6], have been explained in terms of the geometric flexibility of its metal-cyanide-metal linkages. Thermal expansion can also be stopped in some magnetic transition metal alloys below their magnetic ordering temperature, a phenomenon known as the Invar effect, and the possibility of exploiting materials with tuneable positive or negative thermal expansion in industrial applications has led to intense interest in both the Invar effect and negative thermal expansion. Here we report the results of thermal expansion experiments on three magnetic nanocrystals-CuO, MnF2 and NiO-and find evidence for negative thermal expansion in both CuO and MnF2 below their magnetic ordering temperatures, but not in NiO. Larger particles of CuO and MnF2 also show prominent magnetostriction (that is, they change shape in response to an applied magnetic field), which results in significantly reduced thermal expansion below their magnetic ordering temperatures; this behaviour is not observed in NiO. We propose that the negative thermal expansion effect in CuO (which is four times larger than that observed in ZrW2O8) and MnF2 is a general property of nanoparticles in which there is strong coupling between magnetism and the crystal lattice.

  17. On the equisummability of Hermite and Fourier expansions

    Indian Academy of Sciences (India)

    We prove an equisummability result for the Fourier expansions and. Hermite expansions as well as special Hermite expansions. We also prove the uniform boundedness of the Bochner-Riesz means associated to the Hermite expansions for polyradial functions. Keywords. Hermite functions; special Hermite expansions; ...

  18. Expansion Coefficient on Oxides and Oxide Ceramics.

    Science.gov (United States)

    1986-05-01

    Classification) EXPANSION COEFFICIENTS ON OXIDES AND OXIDE CERAMICS 12 PFRSONAL AUTHOR(S) Josephine Covino 13a TYPE OF REPORT 13b TIME COVERED 114 DATE OF REPORT...drastically alter expansion properties of oxides. It has been found that fine-grained (᝺ tm) anisotropic ceramic materials, such as hafnium oxide, hafnium ...Gokhale. "Thermal Expansion of Zircon ," Jap. J. AppZ. Phys., 7 (1968), p. 1126. 34 -- ’-a.’! nw-W’W L. .WW U. .PV _ 77 NWC TP 6663 81. J. L. Amoros, M

  19. Some Improved Nonperturbative Bounds for Fermionic Expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lohmann, Martin, E-mail: marlohmann@gmail.com [Universita di Roma Tre, Dipartimento di Matematica (Italy)

    2016-06-15

    We reconsider the Gram-Hadamard bound as it is used in constructive quantum field theory and many body physics to prove convergence of Fermionic perturbative expansions. Our approach uses a recursion for the amplitudes of the expansion, discovered in a model problem by Djokic (2013). It explains the standard way to bound the expansion from a new point of view, and for some of the amplitudes provides new bounds, which avoid the use of Fourier transform, and are therefore superior to the standard bounds for models like the cold interacting Fermi gas.

  20. Thermal expansion: Metallic elements and alloys. [Handbook

    Science.gov (United States)

    Touloukian, Y. S.; Kirby, R. K.; Taylor, R. E.; Desai, P. D.

    1975-01-01

    The introductory sections of the work are devoted to the theory of thermal expansion of solids and to methods for the measurement of the linear thermal expansion of solids (X-ray methods, high speed methods, interferometry, push-rod dilatometry, etc.). The bulk of the work is devoted to numerical data on the thermal linear expansion of all the metallic elements, a large number of intermetallics, and a large number of binary alloy systems and multiple alloy systems. A comprehensive bibliography is provided along with an index to the materials examined.

  1. El Huayno con Arpa

    OpenAIRE

    Ferrier, Claude; Rüegg, Daniel

    2015-01-01

    El fenómeno musical que este libro estudia proviene de la región de la sierra de Lima y parte de los departamentos de Áncash, Huánuco y Pasco. El arpa - casi siempre con encordado metálico - es un instrumento fundamental de la región, y los huaynos cantados, acompañados por este instrumento son, desde hace décadas, una manifestación musical que se considera típica de la zona. Se puede afirmar que la función tradicional del instrumento es la del acompañamiento de cantantes, incluso cuando el a...

  2. preescolares desnutridos con madres con obesidad y sin obesidad

    Directory of Open Access Journals (Sweden)

    Viridiana Vanessa Conzuelo-González

    2009-01-01

    Full Text Available El primer objetivo fue conocer cuántos menores de cinco años con diferentes grados de desnutrición tienen una madre con sobrepeso/obesidad/ en una comunidad indígena que vive en extrema pobreza y bajo condiciones de migración masculina internacional. El segundo fue comparar tres variables socionutricionales (ingreso familiar, educación de la madre y adecuación nutrimental de la dieta diaria entre estos hogares y los hogares con desnutrición infantil y madres sin obesidad. Se realizó un estudio transversal (2006-2007, en la comunidad mazahua de San Francisco Tepeolulco, Municipio de Temascalcingo; que incluyó a 85 hogares integrados por preescolares con desnutrición inscritos al programa Oportunidades. Se determinó el estado nutrición de los preescolares con indicadores antropométricos y se obtuvo el IMC de las madres de estos infantes. Se aplicó una encuesta socionutricional, incluida el recordatorio de 24 horas, y complementado con la observación participante (cualitativa. Se encontró que 83% de las madres mazahuas presentaron sobrepeso u obesidad. El estado de nutrición de los preescolares con madres con obesidad presentó un porcentaje mayor de desnutrición (76%. En la variable género, se encontró que 54% de los niños con madres con obesidad tenía baja talla. Al relacionar el nivel educativo de la madre, esta variable resultó ser estadísticamente significativa (p=0.015, donde el analfabetismo está más relacionado con la desnutrición infantil que tienen madres de bajo y/o peso normal. La elevada prevalencia de hogares conformados con preescolares con desnutrición y madres con obesidad, es un síntoma más de la pobreza en zonas indígenas en México, con bajo índice de desarrollo humano.

  3. Collisional and collisionless expansion of Yukawa balls.

    Science.gov (United States)

    Piel, Alexander; Goree, John A

    2013-12-01

    The expansion of Yukawa balls is studied by means of molecular dynamics simulations of collisionless and collisional situations. High computation speed was achieved by using the parallel computing power of graphics processing units. When the radius of the Yukawa ball is large compared to the shielding length, the expansion process starts with the blow-off of the outermost layer. A rarefactive wave subsequently propagates radially inward at the speed of longitudinal phonons. This mechanism is fundamentally different from Coulomb explosions, which employ a self-similar expansion of the entire system. In the collisionless limit, the outer layers carry away most of the available energy. The simulations are compared with analytical estimates. In the collisional case, the expansion process can be described by a nonlinear diffusion equation that is a special case of the porous medium equation.

  4. Thermal expansion of doped lanthanum gallates

    Indian Academy of Sciences (India)

    Thermal expansion of several compositions of Sr and Mg-doped LaGaO3 including an -site deficient composition (La0.9Sr0.1)0.98(Ga0.8Mg0.2)O2.821 were measured in the temperature range from 298 to 1273 K. The effect of doping on thermal expansion was studied by varying the composition at one site of the ...

  5. Expansion and rupture of charged microcapsules

    OpenAIRE

    Datta, Sujit S.; Abbaspourrad, Alireza; Weitz, David A

    2014-01-01

    We study the deformations of pH-responsive spherical microcapsules -- micrometer-scale liquid drops surrounded by thin, solid shells -- under the influence of electrostatic forces. When exposed to a large concentration of NaOH, the microcapsules become highly charged, and expand isotropically. We find that the extent of this expansion can be understood by coupling electrostatics with shell theory; moreover, the expansion dynamics is well described by Darcy's law for fluid flow through the mic...

  6. Tissue expansion: Concepts, techniques and unfavourable results

    OpenAIRE

    Milind S Wagh; Varun Dixit

    2013-01-01

    The phenomenon of tissue expansion is observed in nature all the time. The same properties of the human skin to stretch and expand and yield extra skin if placed under continuous stress over a prolonged period of time has been utilised for reconstructive purposes with the help of a silicon balloon inserted under the skin and progressively filled with saline. The technique of tissue expansion is now more than three decades old and has been a value addition to our armamentarium in reconstructiv...

  7. Negative thermal expansion in framework compounds

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... We have studied negative thermal expansion (NTE) compounds with chemi- cal compositions of NX2O8 and NX2O7 (N=Zr, Hf and X=W, Mo, V) and M2O (M=Cu, Ag) using the techniques of inelastic neutron scattering and lattice dynamics. There is a large variation in the negative thermal expansion ...

  8. Russia and the Future Expansion of NATO

    Science.gov (United States)

    2011-03-24

    2001 that he did not intend to let enlargement undermine the potential for U.S.- Russia cooperation. Later in the summer, Putin took a further step...St ra te gy R es ea rc h Pr oj ec t RUSSIA AND THE FUTURE EXPANSION OF NATO BY COLONEL RADEK CERNY Czech Army DISTRIBUTION STATEMENT A...Strategy Research Project 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Russia and the Future Expansion of NATO 5a. CONTRACT

  9. The. delta. expansion and local gauge invariance

    Energy Technology Data Exchange (ETDEWEB)

    Bender, C.M. (Department of Physics, Washington University, St. Louis, Missouri 63130 (US)); Cooper, F. (Department of Physics, Brown University, Providence, Rhode Island 02912 Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexic o 87545); Milton, K.A. (Department of Physics, The Ohio State University, Columbus, Ohio 43210 Department of Physics and Astronomy, University of Oklahoma, Norman, Oklaho ma 73019)

    1989-08-15

    A recently proposed approximation method, called the {delta} expansion, was introduced in the context of a self-interacting scalar field theory. This approximation method offers the hope of obtaining nonperturbative information about a quantum field theory using perturbative techniques. In this paper we extend formally the {delta}-expansion methods to field theories having local gauge symmetry. We then compute the anomaly in the Schwinger model.

  10. Stochastic quantization and 1/N expansion

    Energy Technology Data Exchange (ETDEWEB)

    Brunelli, J.C. [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil); Mendes, R.S. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica

    1992-10-01

    We study the 1/N expansion of field theories in the stochastic quantization method of Parisi and Wu using the supersymmetric functional approach. This formulation provides a systematic procedure to implement the 1/N expansion which resembles the ones used in the equilibrium. The 1/N perturbation theory for the non linear sigma model in two dimensions is worked out as an example. (author). 19 refs., 5 figs.

  11. Fixed Point Theorems for Times Reasonable Expansive Mapping

    Directory of Open Access Journals (Sweden)

    Chen Chunfang

    2008-01-01

    Full Text Available Abstract Based on previous notions of expansive mapping, times reasonable expansive mapping is defined. The existence of fixed point for times reasonable expansive mapping is discussed and some new results are obtained.

  12. Expansive Soil Crack Depth under Cumulative Damage

    Directory of Open Access Journals (Sweden)

    Bei-xiao Shi

    2014-01-01

    Full Text Available The crack developing depth is a key problem to slope stability of the expansive soil and its project governance and the crack appears under the roles of dry-wet cycle and gradually develops. It is believed from the analysis that, because of its own cohesion, the expansive soil will have a certain amount of deformation under pulling stress but without cracks. The soil body will crack only when the deformation exceeds the ultimate tensile strain that causes cracks. And it is also believed that, due to the combined effect of various environmental factors, particularly changes of the internal water content, the inherent basic physical properties of expansive soil are weakened, and irreversible cumulative damages are eventually formed, resulting in the development of expansive soil cracks in depth. Starting from the perspective of volumetric strain that is caused by water loss, considering the influences of water loss rate and dry-wet cycle on crack developing depth, the crack developing depth calculation model which considers the water loss rate and the cumulative damages is established. Both the proposal of water loss rate and the application of cumulative damage theory to the expansive soil crack development problems try to avoid difficulties in matrix suction measurement, which will surely play a good role in promoting and improving the research of unsaturated expansive soil.

  13. Organizadores e cortadores de comprimidos: riscos e restrições ao uso Organizadores y cortadores de comprimidos: riesgos y restricciones del uso Pill organizers and pill cutters: risks and limitations

    Directory of Open Access Journals (Sweden)

    Caroline Ribeiro de Borja-Oliveira

    2013-02-01

    Full Text Available Com base em análise documental, foram discutidas e problematizadas as limitações associadas à utilização de organizadores e cortadores de comprimidos, como questão de saúde pública. Os organizadores destinados ao armazenamento e transporte de comprimidos e cápsulas expõem essas formas farmacêuticas a fatores ambientais dos quais estariam protegidos em suas embalagens originais, comprometendo sua estabilidade, eficácia e segurança. Os cortadores oferecem risco adicional quanto a perda da eficácia, reações adversas e intoxicação. Por outro lado, o transporte de medicamentos pelo usuário é reflexo da conciliação entre autonomia e autocuidado e a partição de comprimidos é necessária para cumprir certos regimes posológicos. Conclui-se que cabe aos profissionais observar e orientar pacientes e cuidadores, visando à adequação dessas condutas e à prevenção dos riscos envolvidos.Objetivo Con base en análisis documental, se discutieron y señalaron los problemas de las limitaciones asociadas a la utilización de organizadores y cortadores de comprimidos, con respecto a la salud pública. Los organizadores destinados al almacenamiento y transporte de comprimidos y cápsulas exponen las formas farmacéuticas a factores ambientales de los cuales estarían protegidos en sus embalajes originales, comprometiendo su estabilidad, eficacia y seguridad. Los cortadores ofrecen riesgo adicional con relación a la pérdida de la eficacia, reacciones adversas e intoxicación. Por otro lado, el transporte de medicamentos por el usuario es reflejo de la conciliación entre autonomía y autocuidado, y la partición de comprimidos es necesaria para cumplir ciertos regímenes posológicos. Se concluye que resta a los profesionales observar y orientar pacientes y cuidadores, buscando la adecuación de esas conductas y la prevención de los riesgos involucrados.In this essay, based on documental analysis, the limitations associated with the

  14. Negative thermal expansion materials: technological key for control of thermal expansion

    Directory of Open Access Journals (Sweden)

    Koshi Takenaka

    2012-01-01

    Full Text Available Most materials expand upon heating. However, although rare, some materials contract upon heating. Such negative thermal expansion (NTE materials have enormous industrial merit because they can control the thermal expansion of materials. Recent progress in materials research enables us to obtain materials exhibiting negative coefficients of linear thermal expansion over −30 ppm K−1. Such giant NTE is opening a new phase of control of thermal expansion in composites. Specifically examining practical aspects, this review briefly summarizes materials and mechanisms of NTE as well as composites containing NTE materials, based mainly on activities of the last decade.

  15. Violencia con el anciano

    Directory of Open Access Journals (Sweden)

    Rita Campillo Motilva

    2002-08-01

    Full Text Available La violencia doméstica es tan antigua como la humanidad misma y se reconocen la violencia infantil, contra la mujer y al anciano, fundamentalmente; siendo este último grupo una población en ascenso por las mayores expectativas de vida de los últimos años. Como resultado de ello, el número de casos de abuso en el anciano se incrementará y el impacto de este abuso sobre la salud debe ser considerado de forma adecuada. La gama de maltratos es variadísima e incluye el abuso físico, emocional, financiero, sexual, por negligencia, negación a brindarle ayuda y otras formas más. Los ancianos con deterioro cognitivo son los más vulnerables. El médico en la atención primaria de salud es un pilar importante en la prevención y educación de este problema.Domestic violence is as old as humanity itself. Child, women and elderly abuse are mainly recognized. The elderly group is increasing due to the higher life expectancy experimented during the last years. As a result, the number of battered elderly will grow and the impact of this abuse on health should be adequately considered. The range of abuse is very wide and it includes physical, emotional, financial and sexual abuse, negligence, rejection to give assistance and others. The elderly with cognitive deterioration are the most vulnerable. The physician at the primary health care level is an important milestone in the prevention and education of this problem.

  16. Mapping Brazilian Cropland Expansion, 2000-2013

    Science.gov (United States)

    Zalles, V.; Hansen, M.; Potapov, P.

    2016-12-01

    Brazil is one of the world's leading producers and exporters of agricultural goods. Despite undergoing significant increases in its cropland area in the last decades, it remains one of the countries with the most potential for further agricultural expansion. Most notably, the expansion in production areas of commodity crops such as soybean, corn, and sugarcane has become the leading cause of land cover conversion in Brazil. Natural land covers, such as the Amazon and Cerrado forests, have been negatively affected by this agricultural expansion, causing carbon emissions, biodiversity loss, altered water cycles, and many other disturbances to ecosystem services. Monitoring of change in cropland area extent can provide relevant information to decision makers seeking to understand and manage land cover change drivers and their impacts. In this study, the freely-available Landsat archive was leveraged to produce a large-scale, methodologically consistent map of cropland cover at 30 m. resolution for the entire Brazilian territory in the year 2000. Additionally, we mapped cropland expansion from 2000 to 2013, and used statistical sampling techniques to accurately estimate cropland area per Brazilian state. Using the Global Forest Change product produced by Hansen et al. (2013), we can disaggregate forest cover loss due to cropland expansion by year, revealing spatiotemporal trends that could advance our understanding of the drivers of forest loss.

  17. Supercritical flow characteristics at abrupt expansion structure

    Science.gov (United States)

    Lim, Jia Jun; Puay, How Tion; Zakaria, Nor Azazi

    2017-10-01

    When dealing with the design of a hydraulic structure, lateral expansion is often necessary for flow emerging at high velocity served as a cross-sectional transition. If the abrupt expansion structure is made to diverge rapidly, it will cause the major part of the flow fail to follow the boundaries. If the transition is too gradual, it will result in a waste of structural material. A preliminary study on the flow structure near the expansion and its relationship with flow parameter is carried out in this study. A two-dimensional depth-averaged model is developed to simulate the supercritical flow at the abrupt expansion structure. Constrained Interpolation Profile (CIP) scheme (which is of third order accuracy) is adopted in the numerical model. Results show that the flow structure and flow characteristics at the abrupt expansion can be reproduced numerically. The validation of numerical result is done against analytical studies. The result from numerical simulation showed good agreement with the analytical solution.

  18. Ultra-low thermal expansion realized in giant negative thermal expansion materials through self-compensation

    Science.gov (United States)

    Shen, Fei-Ran; Kuang, Hao; Hu, Feng-Xia; Wu, Hui; Huang, Qing-Zhen; Liang, Fei-Xiang; Qiao, Kai-Ming; Li, Jia; Wang, Jing; Liu, Yao; Zhang, Lei; He, Min; Zhang, Ying; Zuo, Wen-Liang; Sun, Ji-Rong; Shen, Bao-Gen

    2017-10-01

    Materials with zero thermal expansion (ZTE) or precisely tailored thermal expansion are in urgent demand of modern industries. However, the overwhelming majority of materials show positive thermal expansion. To develop ZTE or negative thermal expansion (NTE) materials as compensators has become an important challenge. Here, we present the evidence for the realization of ultra-low thermal expansion in Mn-Co-Ge-In particles. The bulk with the Ni2In-type hexagonal structure undergoes giant NTE owing to a martensitic magnetostructural transition. The major finding is that the thermal expansion behavior can be totally controlled by modulating the crystallinity degree and phase transition from atomic scale. Self-compensation effect leads to ultra-low thermal expansion with a linear expansion coefficient as small as +0.68 × 10-6/K over a wide temperature range around room temperature. The present study opens an avenue to reach ZTE particularly from the large class of giant NTE materials based on phase transition.

  19. Expansions and Extensions : Ergodic, combinatorial and geometric properties of β-expansions with arbitrary digits

    NARCIS (Netherlands)

    Kalle, C.C.C.J.

    2009-01-01

    Let beta be a real number bigger than 1 and A a finite set of arbitrary real numbers. A beta-expansion with digits in A of a real number x is an expression for x by an infinite sum of fractions with powers of beta in the denominators and elements from A in the numerators. Such expansions can be

  20. [Forum on tissue expansion. Expansion of the scalp. Surgical techniques and clinical applications].

    Science.gov (United States)

    Foyatier, J L; Delay, E; Comparin, J P; Latarjet, J; Masson, C L

    1993-02-01

    Repair of all forms of alopecia is one of the principal applications of scalp expansion. The authors have inserted 400 expansion prostheses, including 20 in the scalp. The surgical technique, choice of material and various types of flaps are described and illustrated by clinical cases of extensive alopecia.

  1. Anisotropic thermal expansion in flexible materials

    Science.gov (United States)

    Romao, Carl P.

    2017-10-01

    A definition of the Grüneisen parameters for anisotropic materials is derived based on the response of phonon frequencies to uniaxial stress perturbations. This Grüneisen model relates the thermal expansion in a given direction (αi i) to one element of the elastic compliance tensor, which corresponds to the Young's modulus in that direction (Yi i). The model is tested through ab initio prediction of thermal expansion in zinc, graphite, and calcite using density functional perturbation theory, indicating that it could lead to increased accuracy for structurally complex systems. The direct dependence of αi i on Yi i suggests that materials which are flexible along their principal axes but rigid in other directions will generally display both positive and negative thermal expansion.

  2. Extrudate Expansion Modelling through Dimensional Analysis Method

    DEFF Research Database (Denmark)

    A new model framework is proposed to correlate extrudate expansion and extrusion operation parameters for a food extrusion cooking process through dimensional analysis principle, i.e. Buckingham pi theorem. Three dimensionless groups, i.e. energy, water content and temperature, are suggested...... to describe the extrudates expansion. From the three dimensionless groups, an equation with three experimentally determined parameters is derived to express the extrudate expansion. The model is evaluated with whole wheat flour and aquatic feed extrusion experimental data. The average deviations...... of the correlation are respectively 5.9% and 9% for the whole wheat flour and the aquatic feed extrusion. An alternative 4-coefficient equation is also suggested from the 3 dimensionless groups. The average deviations of the alternative equation are respectively 5.8% and 2.5% in correlation with the same set...

  3. Actividad deportiva en pacientes con artroplastía total de rodilla

    Directory of Open Access Journals (Sweden)

    Dr. U. Jaime Duboy

    2012-05-01

    Por esto es importante conocer y difundir entre los pacientes y médicos qué restricciones y cuidados se debe tener en estos pacientes para las recomendaciones de actividad física y práctica deportiva que no comprometan la durabilidad del implante, siendo el objetivo de este artículo recalcar estos puntos.

  4. Rapid palatal expansion: the role of microcirculation.

    Science.gov (United States)

    Bilello, G; Currò, G; Messina, P; Scardina, G

    2015-08-01

    Transverse palate modifications fall under expansive orthopedic therapy of the upper maxilla. The only practical approach to the problem on the transverse plane is that of performing the expansion of the maxillary arch through an opening of the median palatal suture. It is important to understand the changes of the vascular network in midpalatal suture following the starting of rapid maxillary expansion. It is critical to maintain the blood supply and circulation for the osteogenesis and bone remodeling after the expansion. The aim of this research was to evaluate the effects of rapid orthopedic expansion (REP) at the microcirculatory level through capillaroscopic examination. Fifteen patients in their developing years between 9 and 15 years of age (average age 12.16 years) were examined. The application of the REP was the first step in the planning of orthopedic-orthodontic treatment which foresaw further stages in the odonto-osseous movement. The method of Biomicroscopic Video-Imaging of the microcirculation of oral mucosa is performed through the technique of computerized capillaroscopy and the related software. From the results it is evident that immediately after achieving the expansion of the upper maxilla (t1), a slight decrease in the number of vessels per mm² can be observed. In addition, a slight ectasia can be observed in these vessels in comparison to t0. Comparing the videocapillaroscopic images of t1 and t2, an increase in the capillaries per mm² can be observed. Ectasia of the capillaries, though subject to strictly individual variables, can be considered perfectly normal and it is compatible with the normal biology and physiology of vessel microcirculation.

  5. Longitudinal expansion of field line dipolarization

    Science.gov (United States)

    Saka, O.; Hayashi, K.

    2017-11-01

    We examine the substorm expansions that started at 1155 UT 10 August 1994 in the midnight sector focusing on the longitudinal (eastward) expansion of field line dipolarization in the auroral zone. Eastward expansion of the dipolarization region was observed in all of the H, D, and Z components. The dipolarization that started at 1155 UT (0027 MLT) from 260° of geomagnetic longitude (CMO) expanded to 351°(PBQ) in about 48 min. The expansion velocity was 0.03-0.04°/s, or 1.9 km/s at 62°N of geomagnetic latitude. The dipolarization region expanding to the east was accompanied by a bipolar event at the leading edge of the expansion in latitudes equatorward of the westward electrojet (WEJ). In the midnight sector at the onset meridian, the Magnetospheric Plasma Analyzer (MAP) on board geosynchronous satellite L9 measured electrons and ions between 10 eV and 40 keV. We conclude from the satellite observations that this dipolarization was characterized by the evolution of temperature anisotropies, an increase of the electron and ion temperatures, and a rapid change in the symmetry axis of the temperature tensor. The field line dipolarization and its longitudinal expansion were interpreted in terms of the slow MHD mode triggered by the current disruption. We propose a new magnetosphere-ionosphere coupling (MI-coupling) mechanism based on the scenario that transmitted westward electric fields from the magnetosphere in association with expanding dipolarization produced electrostatic potential (negative) in the ionosphere through differences in the mobility of collisional ions and collisionless electrons. The field-aligned currents that emerged from the negative potential region are arranged in a concentric pattern around the negative potential region, upward toward the center and downward on the peripheral.

  6. Perfil del trabajador con discapacidad

    OpenAIRE

    CAPGEMINI; FUNDACIÓN ADECCO

    2014-01-01

    Capgemini y la Fundación Adeco analizan y reflexionan sobre empleo de las personas con discapacidad. A pesar de los avances que se están registrando en este ámbito, la situación laboral de las personas con discapacidad aún está lejos de alcanzar las cotas deseadas de normalización: mientras que la tasa de actividad de las personas sin discapacidad se sitúa en el 76,3%, la de las que sí la tienen desciende bruscamente hasta el 36,5%. En otras palabras, un 63,4% de las personas con discapacidad...

  7. Parabolic cyclinder functions : examples of error bounds for asymptotic expansions

    NARCIS (Netherlands)

    R. Vidunas; N.M. Temme (Nico)

    2002-01-01

    textabstractSeveral asymptotic expansions of parabolic cylinder functions are discussedand error bounds for remainders in the expansions are presented. Inparticular Poincaré-type expansions for large values of the argument$z$ and uniform expansions for large values of the parameter areconsidered.

  8. Reseñas y comentarios restricciones de una política óptima de producción industrial en ramas nuevas en economías semi-industrializadas

    Directory of Open Access Journals (Sweden)

    Martínez Astrid

    1989-12-01

    Full Text Available El artículo de Fritsch y Franco se propone analizar las oportunidades que existen en el mercado mundial para ampliar y sostener las exportaciones de manufacturas brasileras y en particular cómo incide la tecnología en el comercio de esos bienes entre el Norte y el Sur del planeta.
    Las ondas de redespliegue industrial al sur, según el trabajo, transfieren procesos de producción cuyos requisitos tecnológicos son el piso del espectro tecnológico en el Norte. A medida que es mayor el progreso tecnológico,
    los requisitos de inserción del Sur se hacen más exigentes. Los llamados NICs son los países que califican primero en los movimientos más recientes que tienen requisitos de inversión de capital y de calificación del trabajo más altos, tales como siderúrgica, astilleros y computadores. El redespliegue ha dado lugar a una redefinición de la 'diversión internacional del trabajo según la cual unos países exportan bienes intensivos en tecnología e importan -bienes de bajo contenido tecnológic o mientras los NICs muestran el patrón contrario. Otros países quedan al margen de este comercio. Las políticas para permanecer en la corriente de intercambio tecnológico en países semi-industrializados deben asumir la tarea de la actualización tecnológica con respaldo de inversión pública y proyección de largo plazo. El esquema usual de promoción industrial en el caso de industrias nacientes que justificaba incluso la protección aduanera mientras se "aprendía haciendo" ha perdido validez en la medida que en las nuevas industrias el proceso de introducción de nuevos productos y de obsolescencia tecnológica es muy rápido.

  9. Soft Manifold Dynamics behind Negative Thermal Expansion

    Science.gov (United States)

    Schlesinger, Z.; Rosen, J. A.; Hancock, J. N.; Ramirez, A. P.

    2008-07-01

    Minimal models are developed to examine the origin of large negative thermal expansion in underconstrained systems. The dynamics of these models reveals how underconstraint can organize a thermodynamically extensive manifold of low-energy modes which not only drives negative thermal expansion but extends across the Brillioun zone. Mixing of twist and translation in the eigenvectors of these modes, for which in ZrW2O8 there is evidence from infrared and neutron scattering measurements, emerges naturally in our model as a signature of the dynamics of underconstraint.

  10. Air expansion in the water rocket

    CERN Document Server

    Romanelli, Alejandro; Madina, Federico González

    2012-01-01

    We study the thermodynamics of the water rocket in the thrust phase, taking into account the expansion of the air with water vapor, vapor condensation and the energy taken from the environment. We set up a simple experimental device with a stationary bottle and verified that the gas expansion in the bottle is well approximated by a polytropic process $PV^\\beta$= constant, where the parameter $\\beta$ depends on the initial conditions. We find an analytical expression for $\\beta $ that only depends on the thermodynamic initial conditions and is in good agreement with the experimental results.

  11. NATO Expansion and Alternative Future Security Alignments,

    Science.gov (United States)

    1995-04-01

    International Security," a joint paper by the Institute for USA and Canada and the Center for Naval Analysis, June 1992. 11. Malcolm Mackintosh , "Reform in the...former Under Secretary of Defense for Policy Fred C. Ikle, who opposes NATO expansion, has observed that "This remedy may seem all the more urgent as...opposition to NATO expansion include Fred C. Ikl6, former Under Secretary of Defense for Policy Charles Kupchan, a former member of the U.S. National

  12. Large J expansion in ABJM theory revisited.

    Science.gov (United States)

    Dimov, H; Mladenov, S; Rashkov, R C

    Recently there has been progress in the computation of the anomalous dimensions of gauge theory operators at strong coupling by making use of the AdS/CFT correspondence. On the string theory side they are given by dispersion relations in the semiclassical regime. We revisit the problem of a large-charge expansion of the dispersion relations for simple semiclassical strings in an [Formula: see text] background. We present the calculation of the corresponding anomalous dimensions of the gauge theory operators to an arbitrary order using three different methods. Although the results of the three methods look different, power series expansions show their consistency.

  13. The Monetary Policy – Restrictive or Expansive?

    Directory of Open Access Journals (Sweden)

    Adam Szafarczyk

    2007-12-01

    Full Text Available The monetary policy plays an important role in macroeconomic policy of government. There is a question concerning type of this policy ñ expansive or restrictive (easy or tidy monetary policy. Unfortunately, we have a lot of criteria. Each of them gives us other answer. So due to equitation of Irving Fisher we have dominantly expansive monetary policy. This same situation exists when we use nominal value of rediscount interest rate of central bank. Opposite result appears when we use real value of this interest rate or level of obligatory reserve. Taking under consideration liquidity on money market we know, that level of interest rate is too high.  

  14. Scenarios of Expansion to Electric Generation Capacity

    Directory of Open Access Journals (Sweden)

    José Somoza-Cabrera

    2017-06-01

    Full Text Available We show the building scenarios of expansion to electric generation capacity enough to supply the demand to 2050. We were using the LEAP facility (Long-range Energy Alternatives Planning System, to simulate dispatch of electricity at minimum cost. Finally, we show the cost-benefice analysis of the technologies availability, included externality and CO2 emission limited. However that we included the externals cost in this analysis, it results insufficient to closed gap between fossil and renewable technologies of electric generation. Nevertheless, in some opportunities the renewable options had very important participations in the minimal cost scenario of expansion.

  15. Expansion of the whole wheat flour extrusion

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2008-01-01

    A new model framework is proposed to describe the expansion of extrudates with extruder operating conditions based on dimensional analysis principle. The Buckingham pi dimensional analysis method is applied to form the basic structure of the model from extrusion process operational parameters. Us....... Using the Central Composite Design (CCD) method, whole wheat flour was processed in a twin-screw extruder with 16 trials. The proposed model can well correlate the expansion of the 16 trials using 3 regression parameters. The average deviation of the correlation is 5.9%....

  16. Cluster expansions for the correlated basis functions theory

    Energy Technology Data Exchange (ETDEWEB)

    Guardiola, R. (Granada Univ. (Spain). Dept. de Fisica Nuclear)

    1982-08-16

    Four kinds of cluster expansions for the calculation of non-diagonal matrix elements of the hamiltonian between correlated states have been derived. The derivation is based on a linearization mechanism for the standard cluster expansions in a configuration mixed state. Particulary simple formulae result for the multiplicative Factor-Aviles-Hartog-Tolhoek expansion and for the exponential form of the Gaudin-Gillespie-Ripka cluster expansion. The resulting expansions are directly usable in finite nuclei.

  17. On Learning Ring-Sum-Expansions

    DEFF Research Database (Denmark)

    Fischer, Paul; Simon, H. -U.

    1992-01-01

    The problem of learning ring-sum-expansions from examples is studied. Ring-sum-expansions (RSE) are representations of Boolean functions over the base {#123;small infinum, (+), 1}#125;, which reflect arithmetic operations in GF(2). k-RSE is the class of ring-sum-expansions containing only monomials...... of length at most k:. term-RSE is the class of ring-sum-expansions having at most I: monomials. It is shown that k-RSE, k>or=1, is learnable while k-term-RSE, k>2, is not learnable if RPnot=NP. Without using a complexity-theoretical hypothesis, it is proven that k-RSE, k>or=1, and k-term-RSE, k>or=2 cannot...... be learned from positive (negative) examples alone. However, if the restriction that the hypothesis which is output by the learning algorithm is also a k-RSE is suspended, then k-RSE is learnable from positive (negative) examples only. Moreover, it is proved that 2-term-RSE is learnable by a conjunction...

  18. Negative thermal expansion in framework compounds

    Indian Academy of Sciences (India)

    electron microscopy, EXAFS and differential scanning calorimetry have been used to study structural properties as a function of temperature for these compounds. In this paper we report the results obtained from our study [14–20] of negative thermal expansion (NTE) compounds with chemical compositions of NX2O8 and.

  19. Polytope expansion of Lie characters and applications

    Energy Technology Data Exchange (ETDEWEB)

    Walton, Mark A., E-mail: walton@uleth.ca [Department of Physics and Astronomy, University of Lethbridge, Lethbridge, Alberta T1K 3M4 (Canada)

    2013-12-15

    The weight systems of finite-dimensional representations of complex, simple Lie algebras exhibit patterns beyond Weyl-group symmetry. These patterns occur because weight systems can be decomposed into lattice polytopes in a natural way. Since lattice polytopes are relatively simple, this decomposition is useful, in addition to being more economical than the decomposition into single weights. An expansion of characters into polytope sums follows from the polytope decomposition of weight systems. We study this polytope expansion here. A new, general formula is given for the polytope sums involved. The combinatorics of the polytope expansion are analyzed; we point out that they are reduced from those of the Weyl character formula (described by the Kostant partition function) in an optimal way. We also show that the weight multiplicities can be found easily from the polytope multiplicities, indicating explicitly the equivalence of the two descriptions. Finally, we demonstrate the utility of the polytope expansion by showing how polytope multiplicities can be used in the calculation of tensor product decompositions, and subalgebra branching rules.

  20. Resonant state expansion of the resolvent

    Energy Technology Data Exchange (ETDEWEB)

    Berggren, T.; Lind, P. (Department of Mathematical Physics, Lund Institute of Technology, P.O. Box 118, S-22100 Lund (Sweden))

    1993-02-01

    An analytic method of generating resonant state expansions from the standard completeness relation of nonrelativistic quantum mechanics is described and shown to reproduce the generalized completeness relations, earlier derived, involving resonant states. The method is then applied to the expansion of the resolvent (the complete Green's function), the symmetry properties of which [ital seem] to be destroyed if a conventional application of the completeness relations is made. These forms of expansions have a continuum term which contains symmetry-restoring contributions and can therefore never vanish identically, nor can it be neglected. The symmetry-conserving form of the expansion has a set of discrete terms which are identical in form to those of the Mittag-Leffler series for the resolvent. In addition, it contains a continuum contribution which in some cases vanishes identically, but in general does not. We illustrate these findings with numerical applictions in which the potential (a square well) is chosen so as to permit analytic evaluation of practically all functions and quantities involved.

  1. Annual cropped area expansion and agricultural production ...

    African Journals Online (AJOL)

    This paper assesses the relationship between annual cropped area expansion and crop output and discusses the implication of such a relationship for environmental management in Benue State, Nigeria. The study was carried out using agricultural production survey (APS) data of five selected crops, namely: rice, sorghum, ...

  2. Hole expansion test of third generation steels

    Science.gov (United States)

    Agirre, Julen; Mendiguren, Joseba; Galdos, Lander; de Argandoña, Eneko Sáenz

    2017-10-01

    The trend towards the implementation of new materials in the chassis of the automobiles is considerably making more complex the manufacturing of the components that built it up. In this scenario materials with higher strengths and lower formabilities are daily faced by tool makers and component producers what reduces the process windows and makes the forming processes to be in the limits of the materials. One of the concerns that tool makers must face during the definition of the tools is the expansion ratios that the holes in the sheet may reach before producing a breakage due to the stretching of the material (also known as edge cracks). For the characterization of such limits, a standard test, the hole expansion test, can be applied so that the limits of the material are known. At the present study, hole expansion tests of a third generation steel, Fortiform1050 with a thickness of 1.2 millimeters have been carried out and compared them to a mild steel, DX54D with a thickness of 0.6 millimeters. A comparison for each material in terms of technology used to punch the hole, mechanical punching vs laser cutting has also been conducted. In addition, the measurement technique (online measurement vs offline measurement) followed in the Hole Expansion Ratio (HER) identification has also been analyzed. Finally, differences between both materials and techniques are presented.

  3. The Asymptotic Expansion Method via Symbolic Computation

    Directory of Open Access Journals (Sweden)

    Juan F. Navarro

    2012-01-01

    Full Text Available This paper describes an algorithm for implementing a perturbation method based on an asymptotic expansion of the solution to a second-order differential equation. We also introduce a new symbolic computation system which works with the so-called modified quasipolynomials, as well as an implementation of the algorithm on it.

  4. Hydrodynamic Gradient Expansion in Gauge Theory Plasmas,

    NARCIS (Netherlands)

    Heller, M.P.; Janik, R.A.; Witaszczyk, P

    2013-01-01

    We utilize the fluid-gravity duality to investigate the large order behavior of hydrodynamic gradient expansion of the dynamics of a gauge theory plasma system. This corresponds to the inclusion of dissipative terms and transport coefficients of very high order. Using the dual gravity description,

  5. Expansion and contraction of finite states

    NARCIS (Netherlands)

    Tamminga, Allard

    2004-01-01

    We present a theory that copes with the dynamics of inconsistent information. A method is set forth to represent possibly inconsistent information by a *finite state*. Next, finite operations for expansion and contraction of finite states are given. No extra-logical element -- a choice function or

  6. A Computational Approach to Competitive Range Expansions

    Science.gov (United States)

    Weber, Markus F.; Poxleitner, Gabriele; Hebisch, Elke; Frey, Erwin; Opitz, Madeleine

    2014-03-01

    Bacterial communities represent complex and dynamic ecological systems. Environmental conditions and microbial interactions determine whether a bacterial strain survives an expansion to new territory. In our work, we studied competitive range expansions in a model system of three Escherichia coli strains. In this system, a colicin producing strain competed with a colicin resistant, and with a colicin sensitive strain for new territory. Genetic engineering allowed us to tune the strains' growth rates and to study their expansion in distinct ecological scenarios (with either cyclic or hierarchical dominance). The control over growth rates also enabled us to construct and to validate a predictive computational model of the bacterial dynamics. The model rested on an agent-based, coarse-grained description of the expansion process and we conducted independent experiments on the growth of single-strain colonies for its parametrization. Furthermore, the model considered the long-range nature of the toxin interaction between strains. The integration of experimental analysis with computational modeling made it possible to quantify how the level of biodiversity depends on the interplay between bacterial growth rates, the initial composition of the inoculum, and the toxin range.

  7. Effects of forest expansion on mountain grassland

    DEFF Research Database (Denmark)

    Guidi, Claudia; Magid, Jakob; Rodeghiero, Mirco

    2014-01-01

    Background and aims. Grassland abandonment followed by forest succession is the dominant land-use change in the European Alps. We studied the impact of current forest expansion on mountain grassland on changes in physical soil organic carbon (SOC) fractions along a land-use and management gradient...

  8. Stakeholder Support for School Food Policy Expansions

    Science.gov (United States)

    Pettigrew, Simone; Pescud, Melanie; Donovan, Robert J.

    2012-01-01

    The aim of this study was to assess the extent to which parents and school-based stakeholders (principals, teachers, canteen managers and Parents & Citizen Committee presidents) are supportive of potential expansions to a new school food policy. Eight additional policy components elicited in preliminary focus groups with parents and 19 additional…

  9. Global Expansion and English Language Learning

    Science.gov (United States)

    Andrade, Maureen Snow

    2016-01-01

    Demand for higher education is global. As institutions extend opportunities beyond their borders, English language proficiency must be considered. This chapter focuses on considerations related to global expansion, with an emphasis on the role of distance English language courses and the distinct considerations in their development.

  10. Taylor series expansions for stationary Markov chains

    NARCIS (Netherlands)

    Heidergott, B.F.; Hordijk, A.

    2003-01-01

    We study Taylor series expansions of stationary characteristics of general-state-space Markov chains. The elements of the Taylor series are explicitly calculated and a lower bound for the radius of convergence of the Taylor series is established. The analysis provided in this paper applies to the

  11. Term Dependence: Truncating the Bahadur Lazarsfeld Expansion.

    Science.gov (United States)

    Losee, Robert M., Jr.

    1994-01-01

    Studies the performance of probabilistic information retrieval systems using differing statistical dependence assumptions when estimating the probabilities inherent in the retrieval model. Experimental results using the Bahadur Lazarsfeld expansion on the Cystic Fibrosis database are discussed that suggest that incorporating term dependence…

  12. Revisting expansive learning for knowledge production and ...

    African Journals Online (AJOL)

    Revisting expansive learning for knowledge production and capability development at postgraduate level in Higher Education Studies. R Niemann. Abstract. Higher education in South Africa is challenged by academic and social demands. Universities, therefore, have to produce graduates who will be able to function ...

  13. On the Convergence of the Virial Expansion

    NARCIS (Netherlands)

    Ramawadh, S.D.

    2015-01-01

    The virial expansion appears in statistical mechanics, an area where physics and mathematics intersect. Throughout this thesis we will mostly ignore the physics and mainly focus on the mathematical aspects. This is a deliberate choice, made for two reasons. Firstly, there are several books that

  14. Critical point anomalies include expansion shock waves

    NARCIS (Netherlands)

    Nannen, N.R.; Guardone, A.; Colonna, P.

    2014-01-01

    From first-principle fluid dynamics, complemented by a rigorous state equation accounting for critical anomalies, we discovered that expansion shock waves may occur in the vicinity of the liquid-vapor critical point in the two-phase region. Due to universality of near-critical thermodynamics, the

  15. The replication of expansive production knowledge

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Yang, Cheng; Madsen, Erik Skov

    2012-01-01

    Purpose – With the aim to support offshore production line replication, this paper specifically aims to explore the use of templates and principles to transfer expansive productive knowledge embedded in a production line and understand the contingencies that influence the mix of these approaches....

  16. Expansion patterns and parallaxes for planetary nebulae

    Science.gov (United States)

    Schönberner, D.; Balick, B.; Jacob, R.

    2018-02-01

    Aims: We aim to determine individual distances to a small number of rather round, quite regularly shaped planetary nebulae by combining their angular expansion in the plane of the sky with a spectroscopically measured expansion along the line of sight. Methods: We combined up to three epochs of Hubble Space Telescope imaging data and determined the angular proper motions of rim and shell edges and of other features. These results are combined with measured expansion speeds to determine individual distances by assuming that line of sight and sky-plane expansions are equal. We employed 1D radiation-hydrodynamics simulations of nebular evolution to correct for the difference between the spectroscopically measured expansion velocities of rim and shell and of their respective shock fronts. Results: Rim and shell are two independently expanding entities, driven by different physical mechanisms, although their model-based expansion timescales are quite similar. We derive good individual distances for 15 objects, and the main results are as follows: (i) distances derived from rim and shell agree well; (ii) comparison with the statistical distances in the literature gives reasonable agreement; (iii) our distances disagree with those derived by spectroscopic methods; (iv) central-star "plateau" luminosities range from about 2000 L⊙ to well below 10 000 L⊙, with a mean value at about 5000 L⊙, in excellent agreement with other samples of known distance (Galactic bulge, Magellanic Clouds, and K648 in the globular cluster M 15); (v) the central-star mass range is rather restricted: from about 0.53 to about 0.56 M⊙, with a mean value of 0.55 M⊙. Conclusions: The expansion measurements of nebular rim and shell edges confirm the predictions of radiation-hydrodynamics simulations and offer a reliable method for the evaluation of distances to suited objects. Results of this paper are based on observations made with the NASA/ESA Hubble Space Telescope in Cycle 16 (GO11122

  17. 216-B-3 expansion ponds closure plan

    Energy Technology Data Exchange (ETDEWEB)

    1994-10-01

    This document describes the activities for clean closure under the Resource Conservation and Recovery Act of 1976 (RCRA) of the 216-B-3 Expansion Ponds. The 216-B-3 Expansion Ponds are operated by the US Department of Energy, Richland Operations Office (DOE-RL) and co-operated by Westinghouse Hanford Company (Westinghouse Hanford). The 216-B-3 Expansion Ponds consists of a series of three earthen, unlined, interconnected ponds that receive waste water from various 200 East Area operating facilities. The 3A, 3B, and 3C ponds are referred to as Expansion Ponds because they expanded the capability of the B Pond System. Waste water (primarily cooling water, steam condensate, and sanitary water) from various 200 East Area facilities is discharged to the Bypass pipe (Project X-009). Water discharged to the Bypass pipe flows directly into the 216-B-3C Pond. The ponds were operated in a cascade mode, where the Main Pond overflowed into the 3A Pond and the 3A Pond overflowed into the 3C Pond. The 3B Pond has not received waste water since May 1985; however, when in operation, the 3B Pond received overflow from the 3A Pond. In the past, waste water discharges to the Expansion Ponds had the potential to have contained mixed waste (radioactive waste and dangerous waste). The radioactive portion of mixed waste has been interpreted by the US Department of Energy (DOE) to be regulated under the Atomic Energy Act of 1954; the dangerous waste portion of mixed waste is regulated under RCRA.

  18. Experimental Analysis on Flow Expansion Over Fan

    Science.gov (United States)

    Sittoni, L.; Paola, C.

    2005-12-01

    We present experimental evidence on the occurrence of large angles of flow expansion with no flow separation over depositional fans. The evolution of a number of self-formed experimental fans was analyzed using overhead images and detailed topographic surveys. Angles of flow expansion up to 45 degrees were found in association with a characteristic bed curvature. Although precise measurements indicate that transverse curvature appeared to slightly decrease downstream over the fans, an approximately constant value of curvature of about 0.1 (r/W = 0.1, where r is the dimensional curvature and W is the maximum width of the fan) fits well all fan sections analyzed. In addition, we found that bed curvature shows a weak proportional dependence with fan expansion angles (alpha around 20 degrees, where alpha is the local plan angle). The curvature appears sufficient to explain the common occurrence of unchannelized, simple fans with opening angles, and hence rates of bedload divergence, much larger than would be predicted from jet theory. We have also analyzed fan development. In our experiments, an instability phenomenon causes a sudden increase in channel width, in association with the formation of a scour. A common development pattern was observed: the upstream-migrating scour initiates flow expansion, inducing in turn the formation of a transient concave heart-shaped fan shape that then slowly develops into a final, steady cone-shaped deposit. Most of the deposition appears to occur during the initial expansion phase. During final steady conditions, fans were also observed to reach values of L/0.5W (L is the final fan length and W is the fan width) approximately constant and in the range 2-4.

  19. con mala calidad de vida

    Directory of Open Access Journals (Sweden)

    Agustín Martín-Rodríguez

    2007-01-01

    Full Text Available En este estudio ex post facto se ha analizado si los familiares de pacientes con mala calidad de vida presentan diferencias en las variables clínicas de personalidad y relaciones familiares en función de que el paciente haya estado o no ingresado en una Unidad de Cuidados Intensivos. Seleccionamos dos grupos: 29 familiares de pacientes traumatizados graves transcurridos cuatro años de su ingreso en una UCI de Traumatología y con mala calidad de vida (debido a secuelas físicas y/o psicológicas tras el ingreso, tales como traumatismos craneoencefálicos, politraumatismos y tetraplejias traumáticas y 32 familiares de pacientes con mala calidad de vida con cuatro años de evolución de su enfermedad física (hipertensión, diabetes, artritis reumatoide y síndrome de intestino irritable que no han estado ingresados en la UCI. Para alcanzar nuestro objetivo empleamos una Encuesta Psicosocial y los siguientes instrumentos: Cuestionario de Análisis Clínico, Escala de Clima Social en la Familia y Escala de Adaptación Psicosocial de la Enfermedad. Los resultados mostraron que los familiares de pacientes con mala calidad de vida que estuvieron ingresados en la UCI hace cuatro años, presentan diferencias significativas en las variables agitación y expresividad comparados con los familiares de pacientes con mala calidad de vida que no han estado ingresados en la UCI.

  20. Encuentro con el tiempo: Adagio con variaciones de Alfredo Aracil

    Directory of Open Access Journals (Sweden)

    Rosa María Rodríguez Hernández

    2012-01-01

    Full Text Available Examinando analíticamente la obra sinfónica Adagio con variaciones de Aracil, estudiaremos los principales componentes para concluir con una evaluación de los mismos. A través de la cronología de la obra de Aracil175, observamos la importancia que adquiere en su trayectoria la memoria; su pensamiento va siempre unido a ésta. Uno de sus recursos principales es la cita; es Adagio con variaciones donde claramente observaremos la memoria lejana e inmediata al tiempo: Wagner es el punto de referencia al pasado, Wolf impulsa hacia el presente, y, Aracil advierte el devenir en cada una de sus variaciones.

  1. Medicaid Expansion and Infant Mortality in the United States.

    Science.gov (United States)

    Bhatt, Chintan B; Beck-Sagué, Consuelo M

    2018-01-18

    To explore the effect of Medicaid expansion on US infant mortality rate. We examined data from 2010 to 2016 and 2014 to 2016 to compare infant mortality rates in states and Washington, DC, that accepted the Affordable Care Act Medicaid expansion (Medicaid expansion states) and states that did not (non-Medicaid expansion states), stratifying data by race/ethnicity. Mean infant mortality rate in non-Medicaid expansion states rose (6.4 to 6.5) from 2014 to 2016 but declined in Medicaid expansion states (5.9 to 5.6). Mean difference in infant mortality rate in Medicaid expansion versus non-Medicaid expansion states increased from 0.573 (P = .08) in 2014 to 0.838 in 2016 (P = .006) because of smaller declines in non-Medicaid expansion (11.0%) than in Medicaid expansion (15.2%) states. The 14.5% infant mortality rate decline from 11.7 to 10.0 in African American infants in Medicaid expansion states was more than twice that in non-Medicaid expansion states (6.6%: 12.2 to 11.4; P = .012). Infant mortality rate decline was greater in Medicaid expansion states, with greater declines among African American infants. Future research should explore what aspects of Medicaid expansion may improve infant survival. (Am J Public Health. Published online ahead of print January 18, 2018: e1-e3. doi:10.2105/AJPH.2017.304218).

  2. Los nenes con los zombies, las nenas con los vampiros

    OpenAIRE

    López Corral, Manuela

    2012-01-01

    En este artículo nos circunscribiremos, dentro de este género literario, a las sagas de reciente salida editorial y, con mayor precisión, a las sagas de novelas románticas para adolescentes tales como Crepúsculo (Stephenie Meyer, 2005), Hush Hush (Becca Fitzpatrick, 2009), Cazadores de Sombras (Cassandra Clare, 2007), Fallen (Lauren Kate, 2010), y otras similares, dejando de lado sagas con otro tipo de particularidades como los citados libros de Harry Potter o los pertenecientes a la trilogía...

  3. Expansion of World Drylands Under Global Warming

    Science.gov (United States)

    Feng, S.; Fu, Q.; Hu, Q. S.

    2012-12-01

    The world drylands including both semi-arid and arid regions comprise of one-third of the global land surfaces, which support 14% of the world's inhabitants and a significant share of the world agriculture. Because of meager annual precipitation and large potential evaporative water loss, the ecosystems over drylands are fragile and sensitive to the global change. By analyzing the observations during 1948-2008 and 20 fully coupled climate model simulations from CMIP5 for the period 1900-2100, this study evaluated the changes of the world drylands that are defined with a modified form of the Thornthwaite's moisture index. The results based on observational data showed that the world drylands are steadily expanding during the past 60 years. The areas occupied by drylands in 1994-2008 is about 2.0×10^6km^2 (or 4%) larger than the average during the 1950s. Such an expansion is also a robust feature in the simulations of the 20 global climate models, though the rate is much smaller in the models. A stronger expanding rate is projected during the first half of this century than the simulations in the last century, followed by accelerating expansion after 2050s under the high greenhouse gas emission scenario (RCP8.5). By the end of this century, the world drylands are projected to be over 58×10^6km^2 (or 11% increase compared to the 1961-1990 climatology). The projected expansion of drylands, however, is not homogeneous over the world drylands, with major expansion of arid regions over the southwest North America, the northern fringe of Africa, southern Africa and Australia. Major expansions of semi-arid regions are projected over the north side of the Mediterranean, southern Africa, North and South America. The global warming is the main factor causing the increase of potential evapotranspiration estimated by Penman-Monteith algorithm, which in turn dominants the expansion of drylands. The widening of Hadley cell, which has impact on both temperature and precipitation

  4. Defining chemical expansion: the choice of units for the stoichiometric expansion coefficient

    DEFF Research Database (Denmark)

    Marrocchelli, Dario; Chatzichristodoulou, Christodoulos; Bishop, Sean R.

    2014-01-01

    Chemical expansion refers to the spatial dilation of a material that occurs upon changes in its composition. When this dilation is caused by a gradual, iso-structural increase in the lattice parameter with composition, it is related to the composition change by the stoichiometric expansion coeffi...... are provided for changes in oxygen content in fluorite, perovskite, and Ruddlesden-Popper (K2NiF4) phase materials used in solid oxide fuel cells....

  5. Unión del Canal del Atazar con la Red de distribución de agua de Madrid (Plaza de Castilla (II

    Directory of Open Access Journals (Sweden)

    López de Berges y de los Santos, Emilio

    1967-05-01

    Full Text Available This paper describes the connecting conduit between the Atazar Canal, which finishes at the El Goloso reservoir, and the water distribution network of Madrid, whose reservoir is at the Plaza de Castilla. The main features of this conduit are: the initial stage of the conduit, the pipe itself, the valves and the final stage of the conduit. Work has been done quickly, and the use of one of the pipes saved Madrid from undergoing strong water restrictions during the summer months. The project was adjudicated by auction, and the price estimate was about 500 million pesetas, which gives some idea of the magnitude of the enterprise.En el presente artículo se describe el conducto de unión del Canal del Atazar —que finaliza en los depósitos de El Goloso— con la red de distribución de Madrid y los depósitos de la Plaza de Castilla. Los elementos más destacados de la conducción son: dispositivo de origen, conducción propiamente dicha, cámaras de válvulas y dispositivo final. Las obras se han llevado a buen ritmo, y la puesta en funcionamiento de una de sus tuberías evitó imponer severas restricciones al abastecimiento de la capital. Los trabajos se adjudicaron por el sistema de subasta con un presupuesto de ejecución material de unos 500 millones de pesetas, lo que da idea de su gran importancia.

  6. REGENERATIVE GAS TURBINES WITH DIVIDED EXPANSION

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Qvale, Einar Bjørn

    2004-01-01

    their efficiency are always of interest. Recently, two independent studies have proposed recuperated gas turbines to be configured with the turbine expansion divided, in order to obtain higher efficiency. The idea is to operate the system with a gas generator and a power turbine, and use the gas from the gas......Recuperated gas turbines are currently drawing an increased attention due to the recent commercialization of micro gas turbines with recuperation. This system may reach a high efficiency even for the small units of less than 100 kW. In order to improve the economics of the plants, ways to improve...... divided expansion can be advantageous under certain circumstances. But, in order for todays micro gas turbines to be competitive, the thermodynamic efficiencies will have to be rather high. This requires that all component efficiencies including the recuperator effectiveness will have to be high...

  7. Off-diagonal expansion quantum Monte Carlo.

    Science.gov (United States)

    Albash, Tameem; Wagenbreth, Gene; Hen, Itay

    2017-12-01

    We propose a Monte Carlo algorithm designed to simulate quantum as well as classical systems at equilibrium, bridging the algorithmic gap between quantum and classical thermal simulation algorithms. The method is based on a decomposition of the quantum partition function that can be viewed as a series expansion about its classical part. We argue that the algorithm not only provides a theoretical advancement in the field of quantum Monte Carlo simulations, but is optimally suited to tackle quantum many-body systems that exhibit a range of behaviors from "fully quantum" to "fully classical," in contrast to many existing methods. We demonstrate the advantages, sometimes by orders of magnitude, of the technique by comparing it against existing state-of-the-art schemes such as path integral quantum Monte Carlo and stochastic series expansion. We also illustrate how our method allows for the unification of quantum and classical thermal parallel tempering techniques into a single algorithm and discuss its practical significance.

  8. Locally-smeared operator product expansions

    Energy Technology Data Exchange (ETDEWEB)

    Monahan, Christopher; Orginos, Kostantinos

    2014-12-01

    We propose a "locally-smeared Operator Product Expansion" (sOPE) to decompose non-local operators in terms of a basis of locally-smeared operators. The sOPE formally connects nonperturbative matrix elements of smeared degrees of freedom, determined numerically using the gradient flow, to non-local operators in the continuum. The nonperturbative matrix elements do not suffer from power-divergent mixing on the lattice, provided the smearing scale is kept fixed in the continuum limit. The presence of this smearing scale prevents a simple connection to the standard operator product expansion and therefore requires the construction of a two-scale formalism. We demonstrate the feasibility of our approach using the example of real scalar field theory.

  9. Morse basis expansion applied to diatomic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Emanuel F. de, E-mail: eflima@rc.unesp.br [Departamento de Estatística, Matemática Aplicada e Computação, Instituto de Geociências e Ciências Exatas, Universidade Estadual Paulista – UNESP, Rio Claro, São Paulo 13506-900 (Brazil)

    2012-02-20

    This work explores the use of the eigenfunctions of the Morse potential with a infinite barrier at long range to solve the radial Schrödinger equation for diatomic molecules. Analytical formulas are obtained for the kinetic energy operator matrix elements in the Morse basis. The Morse basis expansion is applied to find the vibrational–rotational levels of the sodium molecule in the electronic ground state. -- Highlights: ► The Morse potential basis is invoked to find the rovibrational levels of diatomic molecules. ► Analytical formulas for the kinetic energy operator in the Morse basis are obtained. ► The results of the Morse basis expansion show good agreement with the Fourier Grid technique.

  10. Off-diagonal expansion quantum Monte Carlo

    Science.gov (United States)

    Albash, Tameem; Wagenbreth, Gene; Hen, Itay

    2017-12-01

    We propose a Monte Carlo algorithm designed to simulate quantum as well as classical systems at equilibrium, bridging the algorithmic gap between quantum and classical thermal simulation algorithms. The method is based on a decomposition of the quantum partition function that can be viewed as a series expansion about its classical part. We argue that the algorithm not only provides a theoretical advancement in the field of quantum Monte Carlo simulations, but is optimally suited to tackle quantum many-body systems that exhibit a range of behaviors from "fully quantum" to "fully classical," in contrast to many existing methods. We demonstrate the advantages, sometimes by orders of magnitude, of the technique by comparing it against existing state-of-the-art schemes such as path integral quantum Monte Carlo and stochastic series expansion. We also illustrate how our method allows for the unification of quantum and classical thermal parallel tempering techniques into a single algorithm and discuss its practical significance.

  11. 6th International Symposium on Thermal Expansion

    CERN Document Server

    1978-01-01

    This 6th International Symposium on Thermal Expansion, the first outside the USA, was held on August 29-31, 1977 at the Gull Harbour Resort on Hecla Island, Manitoba, Canada. Symposium Chairman was Ian D. Peggs, Atomic Energy of Canada Limited, and our continuing sponsor was CINDAS/Purdue University. We made considerable efforts to broaden the base this year to include more users of expansion data but with little success. We were successful, however, in establishing a session on liquids, an area which is receiving more attention as a logical extension to the high-speed thermophysical property measurements on materials at temperatures close to their melting points. The Symposium had good international representation but the overall attendance was, disappointingly, relatively low. Neverthe­ less, this enhanced the informal atmosphere throughout the meeting with a resultant frank exchange of information and ideas which all attendees appreciated. A totally new item this year was the presentation of a bursary to ...

  12. Asymptotic expansions for the Gaussian unitary ensemble

    DEFF Research Database (Denmark)

    Haagerup, Uffe; Thorbjørnsen, Steen

    2012-01-01

    Let g : R ¿ C be a C8-function with all derivatives bounded and let trn denote the normalized trace on the n × n matrices. In Ref. 3 Ercolani and McLaughlin established asymptotic expansions of the mean value ¿{trn(g(Xn))} for a rather general class of random matrices Xn, including the Gaussian...... aj(g), j ¿ N, as distributions (in the sense of L. Schwarts). We derive a similar asymptotic expansion for the covariance Cov{Trn[f(Xn)], Trn[g(Xn)]}, where f is a function of the same kind as g, and Trn = n trn. Special focus is drawn to the case where and for ¿, µ in C\\R. In this case the mean...

  13. Frostless heat pump having thermal expansion valves

    Science.gov (United States)

    Chen, Fang C [Knoxville, TN; Mei, Viung C [Oak Ridge, TN

    2002-10-22

    A heat pump system having an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant and further having a compressor, an interior heat exchanger, an exterior heat exchanger, a heat pump reversing valve, an accumulator, a thermal expansion valve having a remote sensing bulb disposed in heat transferable contact with the refrigerant piping section between said accumulator and said reversing valve, an outdoor temperature sensor, and a first means for heating said remote sensing bulb in response to said outdoor temperature sensor thereby opening said thermal expansion valve to raise suction pressure in order to mitigate defrosting of said exterior heat exchanger wherein said heat pump continues to operate in a heating mode.

  14. Bond return predictability in expansions and recessions

    DEFF Research Database (Denmark)

    Engsted, Tom; Møller, Stig Vinther; Jensen, Magnus David Sander

    We document that over the period 1953-2011 US bond returns are predictable in expansionary periods but unpredictable during recessions. This result holds in both in-sample and out-of-sample analyses and using both univariate regressions and combination forecasting techniques. A simulation study...... but negative in recessions. The results are also consistent with tests showing that the expectations hypothesis of the term structure holds in recessions but not in expansions. However, the results for bonds are in sharp contrast to results for stocks showing that stock returns are predictable in recessions...... but not in expansions. Thus, our results indicate that there is not a common predictive pattern of stock and bond returns associated with the state of the economy....

  15. Boosting Government Performance with Open Source Software? – A Roadmap for Germany (¿Impulsar el desempeño del estado con software de código abierto? - Plan de trabajo para Alemania

    Directory of Open Access Journals (Sweden)

    Norbert Jesse

    2014-05-01

    Full Text Available English abstract Governments face a considerable pressure from all directions: budget restrictions, citizens’ expectations, demographical trends, local competition from surrounding areas – to name just a few. EGovernment is regarded as an imminent tool to tackle many of these challenges. Obviously, IT itself is object of increasing complexity, constant change and financial implications. This paper outlines how the federal German government follows a strategic roadmap for eGovernment by shaping the objectives and goals for IT expansion. We discuss the role of open source software and how new approaches for software development can turn the ambitious aims into reality. Spanish abstract Los gobiernos se enfrentan a una gran presión desde todas las direcciones: las restricciones presupuestarias, las expectativas de los ciudadanos, las tendencias demográficas, la competencia local- por nombrar algunos. El gobierno electrónico es considerado una herramienta inminente para abordar muchos de estos problemas. Obviamente, las TIC son objetos de complejidad creciente, cambio constante e implicaciones financieras. Este documento describe cómo el gobierno federal alemán sigue una hoja de ruta estratégica para el gobierno electrónico dándole forma a los objetivos y metas para su expansión tecnológica. Se discute el papel del software libre y cómo los nuevos enfoques para el desarrollo de software pueden convertir estos ambiciosos objetivos en realidad.

  16. Cellular Responses to Auxin: Division versus Expansion

    OpenAIRE

    Perrot-Rechenmann, Catherine

    2010-01-01

    The phytohormone auxin is a major regulator of plant growth and development. Many aspects of these processes depend on the multiple controls exerted by auxin on cell division and cell expansion. The detailed mechanisms by which auxin controls these essential cellular responses are still poorly understood, despite recent progress in the identification of auxin receptors and components of auxin signaling pathways. The purpose of this review is to provide an overview of the present knowledge of ...

  17. Multipole expansion in the quantum hall effect

    Energy Technology Data Exchange (ETDEWEB)

    Cappelli, Andrea [INFN, Sezione di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino, Firenze (Italy); Randellini, Enrico [INFN, Sezione di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino, Firenze (Italy); Dipartimento di Fisica, Università di Firenze,Via G. Sansone 1, 50019 Sesto Fiorentino, Firenze (Italy)

    2016-03-15

    The effective action for low-energy excitations of Laughlin’s states is obtained by systematic expansion in inverse powers of the magnetic field. It is based on the W-infinity symmetry of quantum incompressible fluids and the associated higher-spin fields. Besides reproducing the Wen and Wen-Zee actions and the Hall viscosity, this approach further indicates that the low-energy excitations are extended objects with dipolar and multipolar moments.

  18. Tratamiento con implantes Leader-Nano en paciente con oligodoncia

    Directory of Open Access Journals (Sweden)

    Salvador Javier Santos Medina

    2015-03-01

    Full Text Available Los implantes dentales de titanio han revolucionado el mundo de la rehabilitación desde su surgimiento. De manera particular, el empleo de implantes de carga inmediata acorta el tiempo quirúrgico y protésico, con el consiguiente bienestar estético. Se presenta el caso de una paciente femenina de 32 años de edad, con antecedentes de oligodoncia de ambos incisivos laterales superiores y portadora de prótesis parcial acrílica. Fue atendida por el equipo multidisciplinario de implantes en la Clínica Estomatológica Docente “3 de Octubre” y se le realizó tratamiento de rehabilitación integral con implantes Leader-Nano y prótesis fija con corona acrílica sobre dichos implantes. La implantología fue satisfactoria en la paciente; la mejoría estética y funcional, así como la satisfacción de la paciente, fueron los principales logros obtenidos

  19. Acute plasma volume expansion alters cardiovascular but not thermal function during moderate intensity prolonged exercise.

    Science.gov (United States)

    Roy, B D; Green, H J; Grant, S M; Tarnopolsky, M A

    2000-03-01

    To investigate the hypothesis that the increase in plasma volume (PV) that typically occurs with training results in improved cardiovascular and thermal regulation during prolonged exercise, eight untrained males (V(O2)peak = 3.52 +/- 0.12 L x min(-1)) performed 90 min of cycle ergometry at 62% V(O2)peak before and after acute PV expansion. Subjects were infused with a PV-expanding solution (dextran (6%) or Pentaspan (10%)) equivalent to 6.7 mL x kg(-1) body mass (PVX) or acted as their own control (CON) in a randomized order. PVX resulted in a calculated 15.8% increase in resting PV, which relative to CON, was maintained throughout the exercise (P performance without affecting the thermoregulatory response to prolonged cycle exercise.

  20. Spatial Linkage and Urban Expansion: AN Urban Agglomeration View

    Science.gov (United States)

    Jiao, L. M.; Tang, X.; Liu, X. P.

    2017-09-01

    Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  1. SPATIAL LINKAGE AND URBAN EXPANSION: AN URBAN AGGLOMERATION VIEW

    Directory of Open Access Journals (Sweden)

    L. M. Jiao

    2017-09-01

    Full Text Available Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1 Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2 Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980–1990 and second (1990–2000 period. However, it exhibits a negative relationship in the third period (2000–2010, i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3 Results of Zipf’s law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

  2. Huevos enriquecidos con omega 3

    OpenAIRE

    Viteri, Evelyn

    2013-01-01

    El presente trabajo es una contribución al estudio de usos de ingredientes no tradicionales; harina de algas, Macrocystis pyrifera, y la inclusión en raciones para aves de postura destinado a aumentar la concentración de omega 3 del huevo. Objetivo: Evaluar en la alimentación de la gallina la inclusión de harina de alga marina Macrocystis pyrifera con el fin de aumentar el valor de omega 3 en el huevo, y el grado de aceptación de un producto elaborado con el mismo en estudiante...

  3. Frequency dependent thermal expansion in binary viscoelasticcomposites

    Energy Technology Data Exchange (ETDEWEB)

    Berryman, James G.

    2007-12-01

    The effective thermal expansion coefficient beta* of abinary viscoelastic composite is shown to be frequency dependent even ifthe thermal expansion coefficients beta A and beta B of both constituentsare themselves frequency independent. Exact calculations for binaryviscoelastic systems show that beta* is related to constituent valuesbeta A, beta B, volume fractions, and bulk moduli KA, KB, as well as tothe overall bulk modulus K* of the composite system. Then, beta* isdetermined for isotropic systems by first bounding (or measuring) K* andtherefore beta*. For anisotropic systems with hexagonal symmetry, theprincipal values of the thermal expansion beta*perp and beta*para can bedetermined exactly when the constituents form a layered system. In allthe examples studied, it is shown explicitly that the eigenvectors of thethermoviscoelastic system possess non-negative dissipation -- despite thecomplicated analytical behavior of the frequency dependent thermalexpansivities themselves. Methods presented have a variety ofapplications from fluid-fluid mixtures to fluid-solid suspensions, andfrom fluid-saturated porous media to viscoelastic solid-solidcomposites.

  4. Tissue expansion: Concepts, techniques and unfavourable results

    Directory of Open Access Journals (Sweden)

    Milind S Wagh

    2013-01-01

    Full Text Available The phenomenon of tissue expansion is observed in nature all the time. The same properties of the human skin to stretch and expand and yield extra skin if placed under continuous stress over a prolonged period of time has been utilised for reconstructive purposes with the help of a silicon balloon inserted under the skin and progressively filled with saline. The technique of tissue expansion is now more than three decades old and has been a value addition to our armamentarium in reconstructive surgery in all parts of the body. However, it still requires careful patient selection, meticulous planning and faultless execution to successfully carry out the process, which usually lasts for more than 8-12 weeks and involves two sittings of surgery. Any compromise in this process can lead to unfavourable results and complications, some minor, which allow continuance of the process to attain the expected goal and others major, which force abandonment of the process without reaching the expected goal. This article seeks to highlight the intricacies of the concept of tissue expansion, the technique related to flawless execution of the process and likely complications with emphasis on their management. We also present our results from a personal series of 138 patients operated over a period of 18 years between 1994 and 2012.

  5. Precision Quantum Chromodynamics From Heavy Quark Expansions

    CERN Document Server

    Benson, D G

    2005-01-01

    The heavy quark expansion is applied to the semileptonic width of b → c and b → u transitions along with the moments of various decay distributions in the semileptonic b → c transitions. The resulting expressions can be used to improve the precision with which we can extract the values of the CKM matrix elements Vcb and Vub from the data. Heavy quark parameters like mb and m2p are also obtained with values that are completely consistent with theoretical expectations. The observed agreement between the theoretical predictions of the heavy quark expansion and the experimental data tightly constrain the theoretical uncertainty. The heavy quark expansion can also be applied to the photon energy moments in B → Xsγ. The first two of these moments are directly related to mb and m2p . The experimentally imposed cuts on the photon energy spectrum introduce biases into the extracted values of these parameters. Correcting for these biases generates a remarkable agreem...

  6. con dietas suplementadas con Cromo-L-metionina

    Directory of Open Access Journals (Sweden)

    Ram\\u00F3n Garc\\u00EDa-Castillo

    2006-01-01

    Full Text Available Un total de 48 cerdos (Sus scrofa domesticus; 24 machos castrados y 24 hembras cruzados (Yorkshire, Hampshire, Duroc y Landrace de 3,5 a 4,0 meses de edad y 60,0 ± 5,0 kg PV en finalización. Se alimentaron con dietas isoproteícas (14,5 % PC e isoenergéticas (3.400 kcal EM/kg de MS, adicionadas con Cr-L-metionina (MiCroPlex® (0, 200, 400 y 600 ppb. El experimento tuvo una duración de 45 días y se realizó de agosto a noviembre del 2002 en las instalaciones de la Universidad Autónoma Agraria Antonio Narro, localizada en Saltillo, Coahuila, México. Al tener los animales aproximadamente 95 kg PV, se tomó muestra de 15 ml de sangre por cada animal para determinar la concentración de glucosa, ácido úrico, creatinina, urea, proteinas totales y colesterol. Se aplicó un diseño completamente al azar con arreglo factorial 2 x 4; dos para el factor sexo y cuatro para nivel de cromo. Los metabolitos en suero no fueron afectados (P>0,05 por el factor sexo. La glucosa en suero disminuyó (P<0,05 y el colesterol incrementó (P<0,05 con cromo en la dieta. Se concluye que el Cr incrementa el metabolismo de glucosa y disminuye el de colesterol, con lo cual puede haber energía disponible para síntesis de proteína la cual es necesaria para el crecimiento de los animales

  7. Lessons from Early Medicaid Expansions Under Health Reform..

    Data.gov (United States)

    U.S. Department of Health & Human Services — Lessons from Early Medicaid Expansions Under Health Reform, Interviews with Medicaid Officials In a new study entitled Lessons from Early Medicaid Expansions Under...

  8. NiTi Expansion in Operated Unilateral Cleft Palate Patients

    Directory of Open Access Journals (Sweden)

    K Y Poornima

    2011-01-01

    Conclusion : NiTi expansion in operated cleft patients, showed mainly orthodontic expansion. The significant change in the maxillary inter- molar region is due to the direct placement of NiTi palatal expander to 16, 26.

  9. Following Surgically Assisted Rapid Palatal Expansion, Do Tooth-Borne or Bone-Borne Appliances Provide More Skeletal Expansion and Dental Expansion?

    Science.gov (United States)

    Hamedi-Sangsari, Adrien; Chinipardaz, Zahra; Carrasco, Lee

    2017-10-01

    The aim of this study was to compare outcome measurements of skeletal and dental expansion with bone-borne (BB) versus tooth-borne (TB) appliances after surgically assisted rapid palatal expansion (SARPE). This study was performed to provide quantitative measurements that will help the oral surgeon and orthodontist in selecting the appliance with, on average, the greatest amount of skeletal expansion and the least amount of dental expansion. A computerized database search was performed using PubMed, EBSCO, Cochrane, Scopus, Web of Science, and Google Scholar on publications in reputable oral surgery and orthodontic journals. A systematic review and meta-analysis was completed with the predictor variable of expansion appliance (TB vs BB) and outcome measurement of expansion (in millimeters). Of 487 articles retrieved from the 6 databases, 5 articles were included, 4 with cone-beam computed tomographic (CBCT) data and 1 with non-CBCT 3-dimensional cast data. There was a significant difference in skeletal expansion (standardized mean difference [SMD], 0.92; 95% confidence interval [CI], 0.54-1.30; P < .001) in favor of BB rather than TB appliances. However, there was no significant difference in dental expansion (SMD, 0.05; 95% CI, -0.24 to 0.34; P = .03). According to the literature, to achieve more effective skeletal expansion and minimize dental expansion after SARPE, a BB appliance should be favored. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  10. Detection automatique de bulles HI en expansion

    Science.gov (United States)

    Daigle, Anik

    Plusieurs cavités en expansion observées dans le gaz d'hydrogène neutre galactique ont été associées à la présence d'étoiles massives présentant d'intenses vents stellaires ou à des explosions de supernovae. Ces bulles, qui sont remplies de gaz très chaud ( T = 10 5 -10 7 K), tracent donc à la fois les étoiles massives et la phase chaude et ionisée du gaz interstellaire. La morphologie de ces bulles est instable et généralement perturbée par la multitude de structures et de phénomènes existant dans le milieu interstellaire. Leur détection par inspection visuelle est donc difficile et subjective. L'objet de cette thèse est le développement d'une technique de détection automatique et objective de bulles en expansion dans le gaz d'hydrogène neutre de la Voie lactée. Les bulles à progéniteurs stellaires présentent toutes des vitesses d'expansion comprises entre 6 et 19 km s -1 . Une telle caractéristique peut généralement être reconnue dans les spectres en vitesse des cubes de données à 21 cm de l'hydrogène neutre. Notre technique de détection a donc été fondée sur la reconnaissance automatique de la signature d'une expansion à [6, 19] km s -1 dans les spectres en vitesse. La caractérisation et la généralisation de la signature dynamique propre à une bulle en expansion a été confiée à des réseaux de neurones artificiels. Des validations subséquentes, dont certaines liées à la morphologie, ont ensuite été appliquées. La technique a été testée sur onze bulles connues, dont dix ont pu être détectées. La technique a aussi été employée pour la réalisation d'un relevé dans la région du bras de Persée. La distribution spatiale des objets détectés s'est révélée suivre la distribution des étoiles du disque de la Voie lactée. De plus, la distribution selon le rayon et selon la vitesse d'expansion des bulles détectées de rayons plus petits que 10 pc correspondent aux distributions dérivées du mod

  11. Power system capacity expansion planning model considering carbon emissions constraints

    Directory of Open Access Journals (Sweden)

    Diego Adolfo Mejía Giraldo

    2012-01-01

    Full Text Available Este artículo presenta un modelo de planeamiento de expansión de la capacidad de sistemas de potencia considerando restricciones en emisiones de carbono. Además de los aspectos técnicos y económicos considerados usualmente en el proceso de planeamiento, se consideran dos políticas ambientales que consisten en el cobro de un impuesto y un límite anual a las emisiones de dióxido de carbono (CO2. Adicionalmente se ha incluido el retiro gradual de las plantas de generación ineficientes. Este abordaje garantiza una producción de electricidad más limpia en el sistema expandido a un costo relativamente bajo. El modelo propuesto considera la red de transmisión y es aplicado a un sistema de potencia de prueba de 4 regiones y a uno de 11 regiones para un horizonte de planeación de 20 años. Los resultados muestran decisiones de inversión prácticas en términos de sostenibilidad y costos.

  12. La atención a los padres con hijos con necesidades educativas especiales (NEE)

    OpenAIRE

    Claudia María Pernas Pico

    2011-01-01

    Los padres que tienen hijos con necesidades educativas especiales (NEE) necesitan al igual que sus hijos de la intervención del maestro de Audición y Lenguaje con el objetivo primordial de mejorar la comunicación y el lenguaje de los niños. Se pretende en este artículo dar un abanico de posibilidades de cómo se puede intervenir con los padres desde las escuelas: con largas horas de reuniones, con formación, con talleres, con actividades y juegos, con libretas viajeras, con pequeñas pautas, et...

  13. 36 CFR 72.42 - Expansion and new development.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Expansion and new development... INTERIOR URBAN PARK AND RECREATION RECOVERY ACT OF 1978 Grants for Recovery Action Program Development, Rehabilitation and Innovation § 72.42 Expansion and new development. (a) Expansion. Because the UPARR Program is...

  14. Electrical Resistance Alloys and Low-Expansion Alloys

    DEFF Research Database (Denmark)

    Kjer, Torben

    1996-01-01

    The article gives an overview of electrical resistance alloys and alloys with low thermal expansion. The electrical resistance alloys comprise resistance alloys, heating alloys and thermostat alloys. The low expansion alloys comprise alloys with very low expansion coefficients, alloys with very low...

  15. Rapid replacement of bridge deck expansion joints study - phase I.

    Science.gov (United States)

    2014-12-01

    Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

  16. 46 CFR 61.15-12 - Nonmetallic expansion joints.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Nonmetallic expansion joints. 61.15-12 Section 61.15-12... INSPECTIONS Periodic Tests of Piping Systems § 61.15-12 Nonmetallic expansion joints. (a) Nonmetallic expansion joints must be examined externally at each inspection for certification and periodic inspection...

  17. 14 CFR 23.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  18. Con

    DEFF Research Database (Denmark)

    Szpirt, Wladimir; Schwartz, Joseph

    2017-01-01

    The rationale behind the use of plasma exchange (PE) includes the removal of autoantibodies and other plasma constituents, such as cytokines, complement components, neutrophil extracellular traps, and microparticles, and the substitution of missing plasma factors. The more established indications...

  19. Con

    DEFF Research Database (Denmark)

    Graudal, Niels

    2016-01-01

    Scientific evidence to support the recommended salt intake of < 5.8 g/day is virtually non-existingent. There are no randomized controlled trials (RCTs) to investigate the effect of salt reduction (SR) below 5.8 g on health outcomes. The effect of SR on blood pressure (BP) reaches maximal efficac...

  20. High flux expansion divertor studies in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    Soukhanovskii, V A; Maingi, R; Bell, R E; Gates, D A; Kaita, R; Kugel, H W; LeBlanc, B P; Maqueda, R; Menard, J E; Mueller, D; Paul, S F; Raman, R; Roquemore, A L

    2009-06-29

    Projections for high-performance H-mode scenarios in spherical torus (ST)-based devices assume low electron collisionality for increased efficiency of the neutral beam current drive. At lower collisionality (lower density), the mitigation techniques based on induced divertor volumetric power and momentum losses may not be capable of reducing heat and material erosion to acceptable levels in a compact ST divertor. Divertor geometry can also be used to reduce high peak heat and particle fluxes by flaring a scrape-off layer (SOL) flux tube at the divertor plate, and by optimizing the angle at which the flux tube intersects the divertor plate, or reduce heat flow to the divertor by increasing the length of the flux tube. The recently proposed advanced divertor concepts [1, 2] take advantage of these geometry effects. In a high triangularity ST plasma configuration, the magnetic flux expansion at the divertor strike point (SP) is inherently high, leading to a reduction of heat and particle fluxes and a facilitated access to the outer SP detachment, as has been demonstrated recently in NSTX [3]. The natural synergy of the highly-shaped high-performance ST plasmas with beneficial divertor properties motivated a further systematic study of the high flux expansion divertor. The National Spherical Torus Experiment (NSTX) is a mid-sized device with the aspect ratio A = 1.3-1.5 [4]. In NSTX, the graphite tile divertor has an open horizontal plate geometry. The divertor magnetic configuration geometry was systematically changed in an experiment by either (1) changing the distance between the lower divertor X-point and the divertor plate (X-point height h{sub X}), or by (2) keeping the X-point height constant and increasing the outer SP radius. An initial analysis of the former experiment is presented below. Since in the divertor the poloidal field B{sub {theta}} strength is proportional to h{sub X}, the X-point height variation changed the divertor plasma wetted area due to

  1. Zirconium titanate: stability and thermal expansion; Titanato de circonio: estabilidad termodinamica y expansion termica

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Lopez, E.; Moreno, R.; Baudin, C.

    2011-07-01

    Zirconium titanate is a well known compound in the field of electro ceramics, although it has also been used in catalyst and sensors applications. The crystallographic thermal expansion anisotropy of this compound makes it a potential candidate as constituent of structural components. In general, to assure the structural integrity and microstructural homogeneity of a ceramic piece, relatively low cooling rates from the fabrication temperature are required. This requirement is essential for zirconium titanate because thermal expansion as well as phase distribution is affected by small variations in the composition and cooling rate. This work reviews the available data on the phase equilibrium relationships in the systems ZrO{sub 2}-TiO{sub 2} and ZrO{sub 2}-TiO{sub 2}-Y{sub 2}O{sub 3}. The main discrepancies as well as the possible origins of them are discussed. Additionally, the crystallographic thermal expansion data in the current literature are reviewed. (Author) 56 refs.

  2. Private randomness expansion with untrusted devices

    Energy Technology Data Exchange (ETDEWEB)

    Colbeck, Roger; Kent, Adrian, E-mail: rcolbeck@perimeterinstitute.ca, E-mail: a.p.a.kent@damtp.cam.ac.uk [Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, ON N2L 2Y5 (Canada)

    2011-03-04

    Randomness is an important resource for many applications, from gambling to secure communication. However, guaranteeing that the output from a candidate random source could not have been predicted by an outside party is a challenging task, and many supposedly random sources used today provide no such guarantee. Quantum solutions to this problem exist, for example a device which internally sends a photon through a beamsplitter and observes on which side it emerges, but, presently, such solutions require the user to trust the internal workings of the device. Here, we seek to go beyond this limitation by asking whether randomness can be generated using untrusted devices-even ones created by an adversarial agent-while providing a guarantee that no outside party (including the agent) can predict it. Since this is easily seen to be impossible unless the user has an initially private random string, the task we investigate here is private randomness expansion. We introduce a protocol for private randomness expansion with untrusted devices which is designed to take as input an initially private random string and produce as output a longer private random string. We point out that private randomness expansion protocols are generally vulnerable to attacks that can render the initial string partially insecure, even though that string is used only inside a secure laboratory; our protocol is designed to remove this previously unconsidered vulnerability by privacy amplification. We also discuss extensions of our protocol designed to generate an arbitrarily long random string from a finite initially private random string. The security of these protocols against the most general attacks is left as an open question.

  3. Coordinación en Ratas: Ajuste a Restricciones Interdependientes

    Directory of Open Access Journals (Sweden)

    ALEJANDRO SEGURA

    2013-01-01

    Full Text Available El estudio del ajuste conductual a entornos donde las interacciones entre los individuos y sus consecuencias son interdependientes ha derivado en procedimientos que limitan la interacción y restringen la operante a la simple simultaneidad de acciones sobre operandos individuales. En este estudio se evaluó una metodología alterna, en la que se expuso a pares de ratas a ir de un lugar a otro. El acceso al alimento fue contingente al trabajo individual o conjunto, en función de las posibilidades de interacción directa, determinadas por la ubicación de los sujetos. Se identificó coordinación únicamente en las diadas expuestas a interacción directa. El protocolo propuesto permite estudiar el ajuste a pagos interdependientes producto de patrones de acción conjunta.

  4. Maxillary protraction after surgically assisted maxillary expansion

    Directory of Open Access Journals (Sweden)

    Laurindo Zanco Furquim

    2010-06-01

    Full Text Available This case report describes the orthodontic treatment of a 32-year-old woman with a Class III malocclusion, whose chief compliant was her dentofacial esthetics. The pretreatment lateral cephalometric tracings showed the presence of a Class III dentoskeletal malocclusion with components of maxillary deficiency. After discussion with the patient, the treatment option included surgically assisted rapid maxillary expansion (SARME followed by orthopedic protraction (Sky Hook and Class III elastics. Patient compliance was excellent and satisfactory dentofacial esthetics was achieved after treatment completion.

  5. Eta-Expansion Does The Trick

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1995-01-01

    Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta-expansion, and a p......Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta...

  6. Eta-Expansion Does The Trick

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1996-01-01

    Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta-expansion, and a p......Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta...

  7. Eta-expansion does The Trick

    DEFF Research Database (Denmark)

    Danvy, Olivier; Malmkjær, Karoline; Palsberg, Jens

    1996-01-01

    Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta-expansion, and a p......Partial-evaluation folklore has it that massaging one's source programs can make them specialize better. In Jones, Gomard, and Sestoft's recent textbook, a whole chapter is dedicated to listing such “binding-time improvements”: nonstandard use of continuation-passing style, eta...

  8. Exploring the expansion history of the universe.

    Science.gov (United States)

    Linder, Eric V

    2003-03-07

    Exploring the recent expansion history of the universe promises insights into the cosmological model, the nature of dark energy, and potentially clues to high energy physics theories and gravitation. We examine the extent to which precision distance-redshift observations can map out the history, including the acceleration-deceleration transition, and the components and equations of state of the energy density. We consider the ability to distinguish between various dynamical scalar field models for the dark energy, as well as higher dimension and alternate gravity theories. Finally, we present a new, advantageous parametrization for the study of dark energy.

  9. Unique expansions and intersections of Cantor sets

    Science.gov (United States)

    Baker, Simon; Kong, Derong

    2017-04-01

    To each α \\in (1/3,1/2) we associate the Cantor set Γα:={∑i=1∞ɛiαi:ɛi∈{0,1}, i⩾1}. In this paper we consider the intersection {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) for any translation t\\in {R} . We pay special attention to those t with a unique {-1, 0, 1} α-expansion, and study the set Dα:={dimH(Γα∩(Γα+t)):t has a unique {-1,0,1} α-expansion}. We prove that there exists a transcendental number {αKL}≈ 0.394 33\\ldots such that: {{D}α} is finite for α \\in ≤ft({αKL},1/2\\right), {{D}{αKL}}} is infinitely countable, and {{D}α} contains an interval for α \\in ≤ft(1/3,{{αKL}\\right). We also prove that {{D}α} equals ≤ft[0,\\frac{log 2}{-log α}\\right] if and only if α \\in ≤ft(1/3,\\frac{3-\\sqrt{5}}{2}\\right] . As a consequence of our investigation we prove some results on the possible values of \\text{di}{{\\text{m}}H}≤ft({{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right)\\right) when {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) is a self-similar set. We also give examples of t with a continuum of {-1, 0, 1} α-expansions for which we can explicitly calculate \\text{di}{{\\text{m}}H}≤ft({{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right)\\right), and for which {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) is a self-similar set. We also construct α and t for which {{ Γ }α}{\\cap}≤ft({{ Γ }α}+t\\right) contains only transcendental numbers. Our approach makes use of digit frequency arguments and a lexicographic characterisation of those t with a unique {-1, 0, 1} α-expansion.

  10. Capacity Expansion Modeling for Storage Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Elaine; Stoll, Brady; Mai, Trieu

    2017-04-03

    The Resource Planning Model (RPM) is a capacity expansion model designed for regional power systems and high levels of renewable generation. Recent extensions capture value-stacking for storage technologies, including batteries and concentrating solar power with storage. After estimating per-unit capacity value and curtailment reduction potential, RPM co-optimizes investment decisions and reduced-form dispatch, accounting for planning reserves; energy value, including arbitrage and curtailment reduction; and three types of operating reserves. Multiple technology cost scenarios are analyzed to determine level of deployment in the Western Interconnection under various conditions.

  11. Landownership Concentration and the Expansion of Education

    DEFF Research Database (Denmark)

    Cinnirella, Francesco; Hornung, Erik

    2016-01-01

    We study the relationship between large landownership concentration and the expansion of mass education in nineteenth-century Prussia. Cross-sectional estimates show a negative association between landownership concentration and enrollment rates. Fixed-effects panel estimates indicate that regions...... with an initially stronger landownership concentration exhibit increasing enrollment rates. This relationship is not driven by differences in the supply of schooling. We argue that the implementation of agricultural reforms including the stepwise abolition of serfdom is an important driver of the change...

  12. Exploring the expansion history of the universe

    Energy Technology Data Exchange (ETDEWEB)

    Linder, Eric V.

    2002-08-30

    Exploring the recent expansion history of the universe promises insights into the cosmological model, the nature of dark energy, and potentially clues to high energy physics theories and gravitation. They examine the extent to which precision distance-redshift observations can map out the history, including the acceleration-deceleration transition, and the components and equations of state of the energy density. They consider the ability to distinguish between various dynamical scalar field models for the dark energy, as well as higher dimension and alternate gravity theories. Finally, they present a new, advantageous parametrization for the study of dark energy.

  13. Further analysis of the connected moments expansion

    Energy Technology Data Exchange (ETDEWEB)

    Amore, Paolo; Rodriguez, Martin [Facultad de Ciencias, Universidad de Colima, Bernal Diaz del Castillo 340, Colima, Colima (Mexico); Fernandez, Francisco M, E-mail: paolo.amore@gmail.com, E-mail: fernande@quimica.unlp.edu.ar, E-mail: martinalexander.rv@gmail.com [INIFTA (UNLP, CCT La Plata-CONICET), Division Quimica Teorica, Blvd. 113 S/N, Sucursal 4, Casilla de Correo 16, 1900 La Plata (Argentina)

    2011-12-16

    By means of simple quantum-mechanical models we show that under certain conditions the main assumptions of the connected moments expansion (CMX) are no longer valid. In particular, we consider two-level systems: the harmonic oscillator and the pure quartic oscillator. Although derived from such simple models, we think that the results of this investigation may be of utility in future applications of the approach to realistic problems. We show that a straightforward analysis of the CMX exponential parameters may provide a clear indication of the success of the approach. (paper)

  14. Santiago, una ciudad con temor

    Directory of Open Access Journals (Sweden)

    Oviedo S. Enrique

    1999-01-01

    Full Text Available El objetivo general de este artículo es evaluar los efectos de la inseguridad ciudadana en el uso del espacio público. Dicha evaluación exige analizar dos relaciones que se establecen en el ámbito de la violencia: la relación entre victimización y percepción de inseguridad; y la que se establece entre actitudes sociales y resolución pacífica de conflictos nacionales. Para ello, se analizaron las variables victimización, percepción de inseguridad, uso del espacio físico, actitudes hacia el sistema institucional político y social y hacia la resolución de conflictos nacionales, y las posibles relaciones entre ellas. Los datos para realizar el estudio se obtuvieron por medio de una encuesta que se llevó a cabo con 1 200 personas de 18 y 70 años de edad residentes en la ciudad de Santiago. Los resultados indican que Santiago es una ciudad de habitantes con temor y que el aumento de la percepción de inseguridad de sus habitantes contrasta con el hecho de que las tasas de victimización se hayan mantenido, más o menos, constantes en los años que precedieron a la encuesta. El temor se relaciona con el abandono del espacio público físico y sociopolítico, así como con el refugio en los espacios y la vida privados. La actitud de resolver los conflictos por medios no pacíficos es frecuente y se asocia en mayor medida con la inseguridad, la actitud negativa hacia la democracia y la falta de expectativas sobre el futuro del país. Los resultados de este estudio respaldan la idea de que para superar el temor la gente tiende a adaptarse a la realidad adoptando una postura conformista, homogeneizando las creencias y los comportamientos, y sobreestimando la fuerza como medio para resolver las diferencias.

  15. Santiago, una ciudad con temor

    Directory of Open Access Journals (Sweden)

    Enrique Oviedo S.

    1999-04-01

    Full Text Available El objetivo general de este artículo es evaluar los efectos de la inseguridad ciudadana en el uso del espacio público. Dicha evaluación exige analizar dos relaciones que se establecen en el ámbito de la violencia: la relación entre victimización y percepción de inseguridad; y la que se establece entre actitudes sociales y resolución pacífica de conflictos nacionales. Para ello, se analizaron las variables victimización, percepción de inseguridad, uso del espacio físico, actitudes hacia el sistema institucional político y social y hacia la resolución de conflictos nacionales, y las posibles relaciones entre ellas. Los datos para realizar el estudio se obtuvieron por medio de una encuesta que se llevó a cabo con 1 200 personas de 18 y 70 años de edad residentes en la ciudad de Santiago. Los resultados indican que Santiago es una ciudad de habitantes con temor y que el aumento de la percepción de inseguridad de sus habitantes contrasta con el hecho de que las tasas de victimización se hayan mantenido, más o menos, constantes en los años que precedieron a la encuesta. El temor se relaciona con el abandono del espacio público físico y sociopolítico, así como con el refugio en los espacios y la vida privados. La actitud de resolver los conflictos por medios no pacíficos es frecuente y se asocia en mayor medida con la inseguridad, la actitud negativa hacia la democracia y la falta de expectativas sobre el futuro del país. Los resultados de este estudio respaldan la idea de que para superar el temor la gente tiende a adaptarse a la realidad adoptando una postura conformista, homogeneizando las creencias y los comportamientos, y sobreestimando la fuerza como medio para resolver las diferencias.

  16. Molienda asistida con microondas de un coque metalúrgico

    Directory of Open Access Journals (Sweden)

    Ruisánchez, Esteban

    2014-06-01

    Full Text Available Metallurgical cokes are composed of graphitic carbon (s2p2 and different inorganic compounds with very different capacities to absorb microwave radiation. Moreover, due to the electric conductivity shown by the metallurgical cokes, microwave radiation produces electric arcs or microplasmas, which gives rise to hot spots. Therefore, when these cokes are irradiated with microwaves some parts of the particle experiment a rapid heating, while some others do not heat at all. As a result of the different expansion and stress caused by thermal the shock, small cracks and micro-fissures are produced in the particle. The weakening of the coke particles, and therefore an improvement of its grindability, is produced. This paper studies the microwave-assisted grinding of metallurgical coke and evaluates the grinding improvement and energy saving.Los coques metalúrgicos están compuestos mayoritariamente de carbono grafítico (s2p2 y diferentes compuestos inorgánicos con distintas capacidades de absorber la radiación de microondas. Cuando se irradian con microondas fragmentos de estos coques, algunas partes de las partículas experimentan un rápido calentamiento, mientras otras no. Además, debido a que el coque presenta una cierta conductividad eléctrica, al ser irradiados con microondas se producen de forma puntual arcos eléctricos o microplasmas, dando lugar a puntos muy calientes. Como consecuencia de las diferentes dilataciones y tensiones producidas por el choque térmico, se producen en las partículas pequeñas grietas y microfisuras. Esto produce una mayor fragilidad en las partículas de coque y un incremento en la molturabilidad de las mismas. En el presente artículo se estudia la molienda de coque asistida con microondas y se evalúan las mejoras en la molturabilidad y el ahorro de energía producido.

  17. REDUCCIÓN DE ÓXIDOSDE NITROGENO CON CATALIZADORES ZEOLÍTICOS INTERCAMBIADOS CON COBALTO

    National Research Council Canada - National Science Library

    Enrique Alexis García Moya; Felipe Bustamante Londoño; Consuelo Montes de Correa

    2012-01-01

    ... de oxígeno en exceso con varios catalizadores a base de las zeolitas mordenita, ferrierita y ZSM-5 intercambiadas con diferentes cargas de cobalto y con las correspondientes zeolitas en forma acida...

  18. Modelo de evaluación del impacto en Andalucía de las obras civiles realizadas con motivo de la Exposición Universal de Sevilla 1992

    Directory of Open Access Journals (Sweden)

    José Javier Rodríguez Alcaide

    1994-02-01

    Full Text Available Han pasado ya casi sesenta años desde que el enfoque original de Leontief (1936 de caracter input-output abrió un nuevo camino de análisis y proyección del entramado económico. Desde entonces hasta hoy , de modo creciente, rápido y vigoroso han florecido numerosas áreas de estudio y debate alrededor del análisis input-output. Tantos logros vienen a reafirmar la validez de esta línea de pensamiento que pretende dar respuesta a múltiples cuestiones económicas relacionadas con la realidad de los procesos productivos y de intercambio. El análisis input-output ha ayudado a los procedimientos de recogida de datos y a la clasificación de la metodología de dicha recogida. También ha ayudado al diseño de modelos económicos que contemplan restricciones en las capacidades de producción y asimismo el comportamiento optimizador de los agentes sociales. El análisis input-output ha iluminado estudios de carácter nacional y regional. Dentro de este ámbito regional hemos trabajado en diferentes ocasiones y de modo especial en esta contribución que ahora aportamos.

  19. Ubicación y dimensionamiento óptimo de condensadores en sistemas eléctricos de distribución con polución armónica usando recocido simulado

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Ríos

    2006-11-01

    Full Text Available Se emplea el algoritmo de recocido simulado para resolver el problema de la ubicación óptima y la elección del tamaño de bancos de condensadores fijos en sistemas de distribución, cuando existen señales eléctricas con contenido armónico. El modelo matemático contempla como función objetivo el costo de pérdidas en energía y potencia para cada armónico, así como los costos de inversión de los condensadores. Las restricciones incluyen límites de voltaje, calidad de potencia, tamaño, número y ubicación de los bancos de condensadores. Como herramienta de análisis se usa un flujo de carga armónico desarrollado por el grupo de investigación./ The Simulated Annealing Algorithm is used to solve the problem of optimal placement and sizing of fixed capacitor banks in distribution networks in the presence of harmonic electrical signals. In the mathematical model, the objective function includes the cost of power and energy losses at each harmonic frequency, and the inverting cost of capacitor banks. Constrains include voltage limits, power quality limits, number, size and locations of capacitors banks. A harmonic load flow was implemented as analysis tool.

  20. Literatura con mayúsculas

    Directory of Open Access Journals (Sweden)

    Cerrillo, P.

    2006-11-01

    Full Text Available En este trabajo se presenta un acercamiento alconcepto de la Literatura Infantil y Juvenil a travésde una breve visión diacrítica desde sus orígeneshasta nuestros días, subrayando los usos particularesmás característicos de esta literatura en cadaépoca (didáctico, doctrinal, proselitista…. Ademásde señalar sus coincidencias con la Literatura engeneral, se pone también de relieve sus particularidadesy características específicas, en lo que noes sino un nuevo intento de delimitar la caracterizaciónde la LIJ (contenidos, temática, estructuraliteraria, forma, ediciones… y reivindicar estaLiteratura con mayúsculas.

  1. Laboratory simulation of Hot Jupiters atmosphere expansion

    Science.gov (United States)

    Prokopov, P. A.; Shaikhislamov, I. F.; Zakharov, Yu P.; Posukh, V. G.; Melekhov, A. V.; Boyarintsev, E. L.; Ponomarenko, A. G.

    2017-11-01

    Hot Jupiters (HJ) are exoplanets, gas giants with low orbits (≤ 0.1 a.u.). The stellar X-ray and ultraviolet (XUV) radiation energy deposition result in heating ionization and the consequent expansion of planetary atmosphere. Expansion of upper atmosphere under certain conditions could be so large that the majority of light atmospheric constituents overcome the gravitational binding and escape from the planet in a form of hydrodynamic wind. Besides interaction of two counter-streaming plasma flows (stellar wind and ionized upper layers of planet atmosphere), each of this flows interact with planetary magnetic field. In such complex situation laboratory simulation can provide data that can’t be obtained by computer simulation or observation. Experiment was carried out on KI-1 facility: high-vacuum chamber 5m long, 1.2 m in diameter with pressure ∼ 10-6 Torr. Magnetic dipole with two attached laser targets played the role of a planet, and background plasma from θ-pinch used for simulation of stellar wind. As a result, data on a behavior of plasma density and magnetic field were obtained. The novel phenomenon was registered: magnetic field is transferred by the cloud of laser plasma, which was not observed before in experiments or calculations.

  2. Improved Expansion of Random Cayley Graphs

    Directory of Open Access Journals (Sweden)

    Po-Shen Loh

    2004-12-01

    Full Text Available In Random Cayley Graphs and Expanders, N. Alon and Y. Roichman proved that for every ε > 0 there is a finite c(ε such that for any sufficiently large group G, the expected value of the second largest (in absolute value eigenvalue of the normalized adjacency matrix of the Cayley graph with respect to c(ε log |G| random elements is less than ε. We reduce the number of elements to c(εlog D(G (for the same c, where D(G is the sum of the dimensions of the irreducible representations of G. In sufficiently non-abelian families of groups (as measured by these dimensions, log D(G is asymptotically (1/2log|G|. As is well known, a small eigenvalue implies large graph expansion (and conversely; see Tanner84 and AlonMilman84-2,AlonMilman84-1. For any specified eigenvalue or expansion, therefore, random Cayley graphs (of sufficiently non-abelian groups require only half as many edges as was previously known.

  3. Completeness relations and resonant state expansions

    Energy Technology Data Exchange (ETDEWEB)

    Lind, P. (Department of Mathematical Physics, Lund Institute of Technology, P.O. Box 118, S-221 00 Lund (Sweden))

    1993-05-01

    The completeness properties of the discrete set of bound states, virtual states, and resonant states characterizing the system of a single nonrelativistic particle moving in a central cutoff potential are investigated. We do not limit ourselves to the restricted form of completeness that can be obtained from Mittag-Leffler theory in this case. Instead we will make use of the information contained in the asymptotic behavior of the discrete states to get a new approach to the question of eventual overcompleteness. Using the theory of analytic functions we derive a number of completeness relations in terms of discrete states and complex continuum states and give some criteria for how to use them to form resonant state expansions of functions, matrix elements, and Green's functions. In cases where the integral contribution vanishes, the discrete part of the expansions is of the same form as that given by Mittag-Leffler theory but with regularized inner products. We also consider the possibility of using the discrete states as basis in a matrix representation.

  4. Contradictions of TNCs’ Foreign Economic Expansion

    Directory of Open Access Journals (Sweden)

    Melnikov Aleksandr Borisovich

    2014-11-01

    Full Text Available Some directions of the external economic expansion of multinational corporations in modern conditions of globalization, the contradictions generated by these conditions and the conflicts in the system of world economy are presented in the article. The global strategy of functioning of multinational corporation professes the principle of “double standards”. Multinational corporations, on the one hand, support liberalization and internationalization in scales of world reproduction, on the other hand – further redistribution of spheres of influence, and imposing the new world economic order. The functional role of modern multinational corporations is inconsistent. Though they stimulate the tendency of increasing the competitiveness, concentration of the capital and production, at the same time, the monopolization and institutional barriers created by multinational corporation and its structural divisions. Multinational corporations determine the competitive struggle, implement the sanitation mechanism and optimization of world economy. The diversification of multinational corporations’ activity promotes the generation of new requirements and the markets (information, innovations, technologies, services, etc. where individual subjects and competitive forces are formed. It is caused by a progressive functional role of modern multinational corporations in the global economy. Massive penetration into the international business, external expansion of transnational monopolies stimulates economic growth in host countries, promotes specialization, division of labor, cooperation. At the same time, the monopolist form of these processes inevitably leads to numerous negative phenomena, a slow down and inconsistent development of production in the countries-recipients.

  5. Extended Plefka expansion for stochastic dynamics

    Science.gov (United States)

    Bravi, B.; Sollich, P.; Opper, M.

    2016-05-01

    We propose an extension of the Plefka expansion, which is well known for the dynamics of discrete spins, to stochastic differential equations with continuous degrees of freedom and exhibiting generic nonlinearities. The scenario is sufficiently general to allow application to e.g. biochemical networks involved in metabolism and regulation. The main feature of our approach is to constrain in the Plefka expansion not just first moments akin to magnetizations, but also second moments, specifically two-time correlations and responses for each degree of freedom. The end result is an effective equation of motion for each single degree of freedom, where couplings to other variables appear as a self-coupling to the past (i.e. memory term) and a coloured noise. This constitutes a new mean field approximation that should become exact in the thermodynamic limit of a large network, for suitably long-ranged couplings. For the analytically tractable case of linear dynamics we establish this exactness explicitly by appeal to spectral methods of random matrix theory, for Gaussian couplings with arbitrary degree of symmetry.

  6. Thin metastructures with engineered thermal expansion

    Science.gov (United States)

    Gdoutos, Eleftherios E.

    The geometry and constituent materials of metastructures can be used to engineer the thermal expansion coefficient. In this thesis, we design, fabricate, and test thin thermally stable metastructures consisting of bi-metallic unit cells and show how the coefficient of thermal expansion (CTE) of these metastructures can be finely and coarsely tuned by varying the CTE of the constituent materials and the unit cell geometry. Planar and three-dimensional finite element method modeling is used to drive the design and inform experiments, and predict the response of these metastructures. We demonstrate computationally the significance of out-of-plane effects in the metastructure response. We develop an experimental setup using digital image correlation and an infrared camera to experimentally measure full displacement and temperature fields during testing and accurately measure the metastructures' CTE. We experimentally demonstrate high aspect ratio metastructures of Ti/Al and Kovar/Al which exhibit near-zero and negative CTE, respectively. We demonstrate robust fabrication procedures for thermally stable samples with high aspect ratios in thin foil and thin film scales. We investigate the lattice structure and mechanical properties of thin films comprising a near-zero CTE metastructure. The mechanics developed in this work can be used to engineer metastructures of arbitrary CTE and can be extended to three dimensions.

  7. Spontaneous thermal expansion of nematic elastomers

    Science.gov (United States)

    Tajbakhsh, A. R.; Terentjev, E. M.

    2001-10-01

    We study the monodomain (single-crystal) nematic elastomer materials, all side-chain siloxane polymers with the same mesogenic groups and crosslinking density, but differing in the type of crosslinking. Increasing the proportion of long di-functional segments of main-chain nematic polymer, acting as network crosslinking, results in dramatic changes in the uniaxial equilibrium thermal expansion on cooling from the isotropic phase. At higher concentration of main chains their behaviour dominates the elastomer properties. At low concentration of main-chain material, we detect two distinct transitions at different temperatures, one attributed to the main-chain, the other to the side-chain component. The effective uniaxial anisotropy of nematic rubber, r(T)=ell_{allel}/ell_{bot} proportional to the effective nematic order parameter Q(T), is given by an average of the two components and thus reflects the two-transition nature of thermal expansion. The experimental data is compared with the theoretical model of ideal nematic elastomers; applications in high-amplitude thermal actuators are discussed in the end.

  8. Optimizing a Query by Transformation and Expansion.

    Science.gov (United States)

    Glocker, Katrin; Knurr, Alexander; Dieter, Julia; Dominick, Friederike; Forche, Melanie; Koch, Christian; Pascoe Pérez, Analie; Roth, Benjamin; Ückert, Frank

    2017-01-01

    In the biomedical sector not only the amount of information produced and uploaded into the web is enormous, but also the number of sources where these data can be found. Clinicians and researchers spend huge amounts of time on trying to access this information and to filter the most important answers to a given question. As the formulation of these queries is crucial, automated query expansion is an effective tool to optimize a query and receive the best possible results. In this paper we introduce the concept of a workflow for an optimization of queries in the medical and biological sector by using a series of tools for expansion and transformation of the query. After the definition of attributes by the user, the query string is compared to previous queries in order to add semantic co-occurring terms to the query. Additionally, the query is enlarged by an inclusion of synonyms. The translation into database specific ontologies ensures the optimal query formulation for the chosen database(s). As this process can be performed in various databases at once, the results are ranked and normalized in order to achieve a comparable list of answers for a question.

  9. Transmission network expansion planning with simulation optimization

    Energy Technology Data Exchange (ETDEWEB)

    Bent, Russell W [Los Alamos National Laboratory; Berscheid, Alan [Los Alamos National Laboratory; Toole, G. Loren [Los Alamos National Laboratory

    2010-01-01

    Within the electric power literatW''e the transmi ssion expansion planning problem (TNEP) refers to the problem of how to upgrade an electric power network to meet future demands. As this problem is a complex, non-linear, and non-convex optimization problem, researchers have traditionally focused on approximate models. Often, their approaches are tightly coupled to the approximation choice. Until recently, these approximations have produced results that are straight-forward to adapt to the more complex (real) problem. However, the power grid is evolving towards a state where the adaptations are no longer easy (i.e. large amounts of limited control, renewable generation) that necessitates new optimization techniques. In this paper, we propose a generalization of the powerful Limited Discrepancy Search (LDS) that encapsulates the complexity in a black box that may be queJied for information about the quality of a proposed expansion. This allows the development of a new optimization algOlitlun that is independent of the underlying power model.

  10. Tensor integrand reduction via Laurent expansion

    Energy Technology Data Exchange (ETDEWEB)

    Hirschi, Valentin [SLAC, National Accelerator Laboratory,2575 Sand Hill Road, Menlo Park, CA 94025-7090 (United States); Peraro, Tiziano [Higgs Centre for Theoretical Physics, School of Physics and Astronomy,The University of Edinburgh,Edinburgh EH9 3JZ, Scotland (United Kingdom)

    2016-06-09

    We introduce a new method for the application of one-loop integrand reduction via the Laurent expansion algorithm, as implemented in the public C++ library Ninja. We show how the coefficients of the Laurent expansion can be computed by suitable contractions of the loop numerator tensor with cut-dependent projectors, making it possible to interface Ninja to any one-loop matrix element generator that can provide the components of this tensor. We implemented this technique in the Ninja library and interfaced it to MADLOOP, which is part of the public MADGRAPH5{sub A}MC@NLO framework. We performed a detailed performance study, comparing against other public reduction tools, namely CUTTOOLS, SAMURAI, IREGI, PJFRY++ and GOLEM95. We find that Ninja outperforms traditional integrand reduction in both speed and numerical stability, the latter being on par with that of the tensor integral reduction tool GOLEM95 which is however more limited and slower than Ninja. We considered many benchmark multi-scale processes of increasing complexity, involving QCD and electro-weak corrections as well as effective non-renormalizable couplings, showing that Ninja’s performance scales well with both the rank and multiplicity of the considered process.

  11. Renormalized Wick expansion for a modified PQCD

    Energy Technology Data Exchange (ETDEWEB)

    Cabo Montes de Oca, Alejandro [Instituto de Cibernetica, Matematica y Fisica, Group of Theoretical Physics, Vedado, La Habana (Cuba); Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)

    2008-05-15

    The renormalization scheme for the Wick expansion of a modified version of the perturbative QCD introduced in previous works is discussed. Massless QCD is considered by implementing the usual multiplicative scaling of the gluon and quark wave functions and vertices. However, also massive quark and gluon counterterms are allowed in this massless theory since the condensates are expected to generate masses. A natural set of expansion parameters of the physical quantities is introduced: the coupling itself and the two masses m{sub q} and m{sub g} associated to quarks and gluons, respectively. This procedure allows one to implement a dimensional transmutation effect through these new mass scales. A general expression for the new generating functional in terms of the mass parameters m{sub q} and m{sub g} is obtained in terms of integrals over arbitrary but constant gluon or quark fields in each case. Further, the one loop potential is evaluated in more detail in the case when only the quark condensate is retained. This lowest order result again indicates the dynamical generation of quark condensates in the vacuum. (orig.)

  12. pacientes con insuficiencia renal terminal

    Directory of Open Access Journals (Sweden)

    Karen Herrera Herrera

    2011-01-01

    Full Text Available La presente investigación fundamenta en la clínica psicoanalítica el estudio de dos casos de tres personas diagnosticadas con IRT que reciben tratamiento de hemodiálisis, en razón a que dadas las características y el aumento de los reportes que se presentan, ya esto se considera un problema de salud pública. El objetivo principal es describir las características dinámicas del proceso de duelo en pacientes con IRT en un centro de terapia renal de la ciudad de Cartagena. El procedimiento metodológico empleó un diseño de tipo cualitativo; la investigación se desarrolló con un diseño clínico mediante el estudio de casos, y fundamentada en la hermenéutica psicoanalítica. Todo esto respaldado en la historia clínica, la entrevista semiestructurada individual y familiar, los test proyectivos, test del dibujo de la figura humana Machover y TAT de Murray, para la debida integración de los análisis. Se concluye que predominan funciones fallidas de los progenitores y que son individuos provenientes de familias psicosomáticas, que utilizan la enfermedad para obtener un beneficio secundario.

  13. con bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Adriana Mora Antó

    2005-01-01

    Full Text Available Esta investigación dio cuenta de la relación entre el estilo de funcionamiento familiar, los patrones de crianza y las edades de desarrollo evolutivo en niños, nacidos con bajo peso. El estudio descriptivo correlacional se realizó con 41 niños y sus madres, aplicándose cuestionarios sobre funcionamiento familiar, prácticas de crianza y desarrollo infantil. Los resultados señalaron la existencia de un funcionamiento familiar caracterizado por una cohesión amalgamada y una adaptabilidad caótica, una disciplina complaciente, falta de control y de límites claros en la díada madre-hijo. Se trataba de familias monoparentales, donde la temprana edad de concepción, el madresolterismo y el apoyo de la familia extensa eran constantes. Las edades evolutivas registradas indicaron un desarrollo inferior a la edad cronológica, en la mayor parte de los casos; sin embargo, éstas tendieron a ser superiores al compararlas con la edades reales de los infantes. No se encontró una correlación estadísticamente significativa entre la edad de desarrollo y los diferentes factores del funcionamiento familiar para algunos de los rangos de edad considerados; sin embargo, no se lo descartó por completo, especialmente en lo referente al optimismo familiar

  14. The Game Object Model and Expansive Learning: Creation, Instantiation, Expansion, and Re-representation

    Science.gov (United States)

    Amory, Alan; Molomo, Bolepo; Blignaut, Seugnet

    2011-01-01

    In this paper, the collaborative development, instantiation, expansion and re-representation as research instrument of the Game Object Model (GOM) are explored from a Cultural Historical Activity Theory perspective. The aim of the paper is to develop insights into the design, integration, evaluation and use of video games in learning and teaching.…

  15. Establecimiento del cálculo del diámetro de cresta exterior de un engranaje cónico con técnicas de grafos. // Procedure for the calculation of outer tip diameter on straight bevel gear by means of graphs technique.

    Directory of Open Access Journals (Sweden)

    G. González Rey

    2007-09-01

    Full Text Available Mediante un modelo matemático son dadas las principales relaciones entre los parámetros geométricos básicos requeridosen la evaluación del diámetro de cresta exterior de un engranaje ortogonal de ruedas cónicas con dientes rectos y suma decorrecciones radiales iguales a cero. Adicionalmente, serán brindados algunos resultados que asocian la correspondenciaentre una geometría racional y la capacidad de carga de un engranaje cónico con restricciones del diámetro de crestaexterior. Para la determinación de los procedimientos de cálculo, los problemas planteados sobre los modelos matemáticoshan sido serán representados por medio de grafos bicromáticos.Palabras claves: Engranajes cónicos, diseño racional, modelo matemático._______________________________________________________________________________Abstract:By means of a mathematical model, the main relations for the evaluation of the outer tip diameter on straight bevelgear with sum of the profile shift coefficients equal to zero are given. Additionally, some results associated with arational geometry and high load capacities of straight bevel gear with restrictions in the outer tip diameter arepresented. For the determination of the calculation procedures based on mathematical models was used thetechnique of representation by means of graphs.Key words: Straight bevel gear, rational design, mathematical models, graphs technique.

  16. The SWAP Upper Atmosphere Expansion Benchmark

    Science.gov (United States)

    Fuller-Rowell, T. J.; Zesta, E.; Basu, S.; Black, C.; Emmert, J. T.; Sutton, E. K.; Thayer, J. P.; Codrescu, M.; Fedrizzi, M.; Tobiska, W. K.; Crowley, G.; Pilinski, M.; Bowman, B. R.; Woods, T. N.; Chamberlin, P. C.

    2016-12-01

    Atmospheric expansion during extreme events gives rise to increases in neutral density at low-Earth orbit altitudes, which poses two distinct risks to operational spacecraft. The first is the direct effect of enhanced drag on the spacecraft, changing its orbit, increasing the uncertainty of its position, and reducing the orbital lifetime. The second is the indirect effect of atmospheric expansion on the ability to monitor the trajectories of debris, including objects with high area-to-mass ratios, for collision avoidance at all times. The Benchmark for neutral density is defined relative to the empirical neutral density reference models, e.g., JB2008 or NRLMSIS-00. These models are used as a reference in order to extrapolate the response to a 100-year and theoretical maximum event. The Benchmark is also defined for neutral winds: in-track winds change apparent density along an orbit; cross-track winds influence orbit trajectory. The Benchmark is established at three altitudes: 250 km, 400 km, and 850 km, and quantifies the impact from solar ultraviolet radiation (EUV and FUV) at low, medium, and high solar activity on timescales greater than one day; EUV enhancement during impulsive events, such as solar flares; and coronal mass ejections (CMEs) driving geomagnetic storms. A 100-year and theoretical maximum estimate of the peak daily F10.7 proxy are 390 and 500 units, respectively, which would increase global mean density by 100% and 160% at 400 km altitude above the empirical model values at an F10.7 of 240 units. Estimates for a 100-year flare are X30 with a theoretical maximum of X40. The response to an X30 or X40 flare would produce a 75% and 135% density increase, respectively, on the dayside at 400 km altitude at a median solar flux level of 150 sfu. For a Carrington storm the thermospheric temperature is expected to exceed 4000 K, and neutral density is predicted to exceed empirical model estimates of the response to a Bastille or Halloween-like storm by a

  17. Progressive GAA.TTC repeat expansion in human cell lines.

    Science.gov (United States)

    Ditch, Scott; Sammarco, Mimi C; Banerjee, Ayan; Grabczyk, Ed

    2009-10-01

    Trinucleotide repeat expansion is the genetic basis for a sizeable group of inherited neurological and neuromuscular disorders. Friedreich ataxia (FRDA) is a relentlessly progressive neurodegenerative disorder caused by GAA.TTC repeat expansion in the first intron of the FXN gene. The expanded repeat reduces FXN mRNA expression and the length of the repeat tract is proportional to disease severity. Somatic expansion of the GAA.TTC repeat sequence in disease-relevant tissues is thought to contribute to the progression of disease severity during patient aging. Previous models of GAA.TTC instability have not been able to produce substantial levels of expansion within an experimentally useful time frame, which has limited our understanding of the molecular basis for this expansion. Here, we present a novel model for studying GAA.TTC expansion in human cells. In our model system, uninterrupted GAA.TTC repeat sequences display high levels of genomic instability, with an overall tendency towards progressive expansion. Using this model, we characterize the relationship between repeat length and expansion. We identify the interval between 88 and 176 repeats as being an important length threshold where expansion rates dramatically increase. We show that expansion levels are affected by both the purity and orientation of the repeat tract within the genomic context. We further demonstrate that GAA.TTC expansion in our model is independent of cell division. Using unique reporter constructs, we identify transcription through the repeat tract as a major contributor to GAA.TTC expansion. Our findings provide novel insight into the mechanisms responsible for GAA.TTC expansion in human cells.

  18. Welfare – con o senza stato

    DEFF Research Database (Denmark)

    Bengtsson, Steen

    Welfare – con o senza stato analizza una vasta gamma di servizi sociali presenti a Padova, comprandoli con quelli di una cittá di dimensioni simili, Århus. La ricerca pertanto illustra la concreta erticolazione del sisterma di sicurezza sociale danese, confrontadolo con quello realizzato del nord...

  19. Conflation: a new type of accelerated expansion

    Energy Technology Data Exchange (ETDEWEB)

    Fertig, Angelika; Lehners, Jean-Luc; Mallwitz, Enno [Max-Planck-Institute for Gravitational Physics (Albert-Einstein-Institute),Am Mühlenberg 1, Potsdam-Golm, 14476 (Germany)

    2016-08-31

    In the framework of scalar-tensor theories of gravity, we construct a new kind of cosmological model that conflates inflation and ekpyrosis. During a phase of conflation, the universe undergoes accelerated expansion, but with crucial differences compared to ordinary inflation. In particular, the potential energy is negative, which is of interest for supergravity and string theory where both negative potentials and the required scalar-tensor couplings are rather natural. A distinguishing feature of the model is that, for a large parameter range, it does not significantly amplify adiabatic scalar and tensor fluctuations, and in particular does not lead to eternal inflation and the associated infinities. We also show how density fluctuations in accord with current observations may be generated by adding a second scalar field to the model. Conflation may be viewed as complementary to the recently proposed anamorphic universe of Ijjas and Steinhardt.

  20. DISRUPTING SHOCKS IN POSTWAR GLOBAL ECONOMIC EXPANSION

    Directory of Open Access Journals (Sweden)

    Dumitru FILIPEANU

    2016-06-01

    Full Text Available The coherence of the global economic system, created by its upswing in the first postwar decades, started to crumble in the ’70s. The destabilizing shocks affected the entire world, but in an uneven manner, in different geographical areas and at different times, being felt most acutely, with devastating economic and social effects, in Third World countries. Although the developed countries were affected as well, they always had means to combat or to diminish the adverse effects of the crises, leading to "gentler" consequences. This paper focuses on four main aspects in postwar global economic expansion, namely: the ’70s – the international monetary crisis and the oil shocks; the foreign debt crisis; the Latin American debt crisis, the Asian financial crises and the current global crisis.

  1. A non-perturbative operator product expansion

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, W. [Universidad Nacional Autonoma de Mexico, Distrito Federal (Mexico). Inst. de Ciencias Nucleares; Cundy, N.; Goeckeler, M. [Regensburg Univ. (DE). Inst. fuer Theoretische Physik] (and others)

    2009-10-15

    Nucleon structure functions can be observed in Deep Inelastic Scattering experiments, but it is an outstanding challenge to confront them with fully non-perturbative QCD results. For this purpose we investigate the product of electromagnetic currents (with large photonmomenta) between quark states (of low momenta). By means of an Operator Product Expansion the structure function can be decomposed into matrix elements of local operators, and Wilson coefficients. For consistency both have to be computed non-perturbatively. Here we present precision results for a set of Wilson coefficients. They are evaluated from propagators for numerous quark momenta on the lattice, where the use of chiral fermions suppresses undesired operator mixing. This overdetermines the Wilson coefficients, but reliable results can be extracted by means of a Singular Value Decomposition. (orig.)

  2. The replication of expansive production knowledge

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Yang, Cheng; Madsen, Erik Skov

    2012-01-01

    ; and (2) rather than being viewed as alternative approaches, templates and principles should be seen as complementary once the transfer motive moves beyond pure replication. Research limitations – The concepts introduced in this paper were derived from two Danish cases. While acceptable for theory......Purpose – With the aim to support offshore production line replication, this paper specifically aims to explore the use of templates and principles to transfer expansive productive knowledge embedded in a production line and understand the contingencies that influence the mix of these approaches...... exploration, the small sample size is an obvious limitation for generalisation. Practical implications – A roadmap for knowledge transfer within the replication of a production line is suggested, which, together with four managerial suggestions, provides strong support and clear directions to managers...

  3. Sectoral and regional expansion of emissions trading

    Energy Technology Data Exchange (ETDEWEB)

    Boehringer, Christoph; Bouwe, Dijkstra; Rosendahl, Knut Einar

    2011-07-01

    We consider an international emissions trading scheme with partial sectoral and regional coverage. Sectoral and regional expansion of the trading scheme is beneficial in aggregate, but not necessarily for individual countries. We simulate international CO{sub 2} emission quota markets using marginal abatement cost functions and the Copenhagen 2020 climate policy targets for selected countries that strategically allocate emissions in a bid to manipulate the quota price. Quota exporters and importers generally have conflicting interests about admitting more countries to the trading coalition, and our results indicate that some countries may lose substantially when the coalition expands in terms of new countries. For a given coalition, expanding sectoral coverage makes most countries better off, but some countries (notably the USA and Russia) may lose out due to loss of strategic advantages. In general, exporters tend to have stronger strategic power than importers.(Author)

  4. Population Genetics of Three Dimensional Range Expansions

    Science.gov (United States)

    Lavrentovich, Maxim; Nelson, David

    2014-03-01

    We develop a simple model of genetic diversity in growing spherical cell clusters, where the growth is confined to the cluster surface. This kind of growth occurs in cells growing in soft agar, and can also serve as a simple model of avascular tumors. Mutation-selection balance in these radial expansions is strongly influenced by scaling near a neutral, voter model critical point and by the inflating frontier. We develop a scaling theory to describe how the dynamics of mutation-selection balance is cut off by inflation. Genetic drift, i.e., local fluctuations in the genetic diversity, also plays an important role, and can lead to the extinction even of selectively advantageous strains. We calculate this extinction probability, taking into account the effect of rough population frontiers.

  5. Expansion of museums in Central Europe?

    Directory of Open Access Journals (Sweden)

    Jagodzińska, Katarzyna

    2015-06-01

    Full Text Available The paper presents reflections on the specificity of collections and museums of contemporary art in Central Europe and considers a possibility of creating a regional alternative for the West. The analysis is conducted in the context of the expansionist policy of contemporary museums – notably the Louvre, the Guggenheim Foundation, and the Hermitage – whose numerous new development projects gave rise to a number of dilemmas in the museological world. The author discusses global "museum brands" that invest in Central Europe and addresses the possible profits of the expansion of such "concerns" for culture in the region, as well as emphasises the potential of the region itself, which may be used for its development without the avail of the internationally renowned collectors' names.

  6. Large-spin expansions of GKP strings

    Science.gov (United States)

    Floratos, Emmanuel; Georgiou, George; Linardopoulos, Georgios

    2014-03-01

    We demonstrate that the large-spin expansion of the energy of Gubser-Klebanov-Polyakov (GKP) strings that rotate in ℝ × S2 and AdS3 can be expressed in terms of Lambert's W-function. We compute the leading, subleading and next-to-subleading series of exponential corrections to the infinite-volume dispersion relation of GKP strings that rotate in ℝ × S2. These strings are dual to the long = 4 SYM operators +… and provide their scaling dimensions at strong coupling. We also show that the strings obey a short-long (strings) duality. For the folded GKP strings that spin inside AdS3 and are dual to twist-2 operators, we confirm the known formulas for the leading and next-to-leading coefficients of their anomalous dimensions and derive the corresponding expressions for the next-to-next-to-leading coefficients.

  7. EMPIRE ULTIMATE EXPANSION: RESONANCES AND COVARIANCES.

    Energy Technology Data Exchange (ETDEWEB)

    HERMAN,M.; MUGHABGHAB, S.F.; OBLOZINSKY, P.; ROCHMAN, D.; PIGNI, M.T.; KAWANO, T.; CAPOTE, R.; ZERKIN, V.; TRKOV, A.; SIN, M.; CARSON, B.V.; WIENKE, H. CHO, Y.-S.

    2007-04-22

    The EMPIRE code system is being extended to cover the resolved and unresolved resonance region employing proven methodology used for the production of new evaluations in the recent Atlas of Neutron Resonances. Another directions of Empire expansion are uncertainties and correlations among them. These include covariances for cross sections as well as for model parameters. In this presentation we concentrate on the KALMAN method that has been applied in EMPIRE to the fast neutron range as well as to the resonance region. We also summarize role of the EMPIRE code in the ENDF/B-VII.0 development. Finally, large scale calculations and their impact on nuclear model parameters are discussed along with the exciting perspectives offered by the parallel supercomputing.

  8. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

    Vogel, Valerie; Pedersen, Jes Søe; Giraud, Tatiana

    2010-01-01

    Aim The aim of this study was to determine the number of successful establishments of the invasive Argentine ant outside native range and to see whether introduced supercolonies have resulted from single or multiple introductions. We also compared the genetic diversity of native versus introduced...... supercolonies to assess the size of the propagules (i.e. the number of founding individuals) at the origin of the introduced supercolonies. Location Global. Methods We used mitochondrial DNA (mtDNA) markers and microsatellite loci to study 39 supercolonies of the Argentine ant Linepithema humile covering both......) and secondary introductions (from sites with established invasive supercolonies) were important in the global expansion of the Argentine ant. In combination with the similar social organization of colonies in the native and introduced range, this indicates that invasiveness did not evolve recently as a unique...

  9. Quantization Noise Shaping on Arbitrary Frame Expansions

    Directory of Open Access Journals (Sweden)

    Boufounos Petros T

    2006-01-01

    Full Text Available Quantization noise shaping is commonly used in oversampled A/D and D/A converters with uniform sampling. This paper considers quantization noise shaping for arbitrary finite frame expansions based on generalizing the view of first-order classical oversampled noise shaping as a compensation of the quantization error through projections. Two levels of generalization are developed, one a special case of the other, and two different cost models are proposed to evaluate the quantizer structures. Within our framework, the synthesis frame vectors are assumed given, and the computational complexity is in the initial determination of frame vector ordering, carried out off-line as part of the quantizer design. We consider the extension of the results to infinite shift-invariant frames and consider in particular filtering and oversampled filter banks.

  10. The new Medicaid debate: expansion or retrenchment?

    Science.gov (United States)

    2001-01-01

    Health advocates are facing a sea-change in Washington. Comprehensive federal health care reform eluded the nation under the Clinton Administration, but incremental progress through state-based Medicaid expansions and new CHIP programs was widespread, giving rise to some innovative state efforts to cover more of the uninsured. Washington's support was instrumental in those efforts, but the second Bush Administration seems intent on reversing that direction. To protect--and build upon--these nascent Medicaid efforts, advocates will have to mount careful strategies in defense of Medicaid. This States of Health looks at the dangers that may lie ahead and suggests how advocates can respond to keep Medicaid moving in the right direction.

  11. A collisionless plasma thruster plume expansion model

    Science.gov (United States)

    Merino, Mario; Cichocki, Filippo; Ahedo, Eduardo

    2015-06-01

    A two-fluid model of the unmagnetized, collisionless far region expansion of the plasma plume for gridded ion thrusters and Hall effect thrusters is presented. The model is integrated into two semi-analytical solutions valid in the hypersonic case. These solutions are discussed and compared against the results from the (exact) method of characteristics; the relative errors in density and velocity increase slowly axially and radially and are of the order of 10-2-10-3 in the cases studied. The plasma density, ion flux and ambipolar electric field are investigated. A sensitivity analysis of the problem parameters and initial conditions is carried out in order to characterize the far plume divergence angle in the range of interest for space electric propulsion. A qualitative discussion of the physics of the secondary plasma plume is also provided.

  12. The Dynamics of Regional and Global Expansion

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Nielsen, Bo Bernhard; Osegowitsch, Tom

    2015-01-01

    presence over time. The authors test the resulting hypotheses using sales data from a sample of 220 of the world’s largest MNEs over the period 1995-2005. The authors focus specifically on the relationship between levels of market penetration inside and outside the home region and rates of change in each......Purpose – The purpose of this paper is to model and test the dynamics of home-regional and global penetration by multi-national enterprises (MNEs). Design/methodology/approach – Drawing on international business (IB) theory, the authors model MNEs adjusting their home-regional and global market...... domain. Findings – The authors demonstrate that MNEs do penetrate both home-regional and global markets, often simultaneously, and that penetration levels often oscillate within an MNE over time. The authors show firms’ rates of regional and global expansion to be affected by their existing regional...

  13. Expansive focal cemento-osseous dysplasia.

    Science.gov (United States)

    Bulut, Emel Uzun; Acikgoz, Aydan; Ozan, Bora; Zengin, Ayse Zeynep; Gunhan, Omer

    2012-01-01

    To present a case of expansive focal cemento-osseous dysplasia and emphasize the importance of differential diagnosis. Cemento-osseous dysplasia is categorized into three subtypes on the basis of the clinical and radiographic features: Periapical, focal and florid. The focal type exhibits a single site of involvement in any tooth-bearing or edentulous area of the jaws. These lesions are usually asymptomatic; therefore, they are frequently diagnosed incidentally during routine radiographic examinations. Lesions are usually benign, show limited growth, and do not require further surgical intervention, but periodic follow-up is recommended because occasionally, this type of dysplasia progresses into florid osseous dysplasia and simple bone cysts are formed. A 24-year-old female patient was referred to our clinic for swelling in the left edentulous mandibular premolarmolar region and felt discomfort when she wore her prosthetics. She had no pain, tenderness or paresthesia. Clinical examination showed that the swelling in the posterior mandible that was firm, nonfluctuant and covered by normal mucosa. On panoramic radiography and computed tomography, a well defined lesion of approximately 1.5 cm in diameter of mixed density was observed. The swelling increased slightly in size over 2 years making it difficult to use prosthetics and, therefore, the lesion was totally excised under local anesthesia, and surgical specimens were submitted for histopathological examination. The histopathological diagnosis was focal cemento-osseous dysplasia. In the present case, because of the increasing size of the swelling making it difficult to use prosthetics, young age of the patient and localization of the lesion, in the initial examination, cemento-ossifying fibroma was suspected, and the lesion was excised surgically; the histopathological diagnosis confirmed it as focal cemento-osseous dysplasia. We present a case of expansive focal cemento-osseous dysplasia. Differential diagnosis

  14. Secadero tendalero con chimenea solar

    OpenAIRE

    Iriarte, Adolfo Antonio; Bistoni, S.; Luque, V.; Lara, M.; Brizuela, L.

    2017-01-01

    El secado solar de frutas y hortalizas está siendo utilizado en distintos lugares del mundo y particularmente en Argentina. Si bien existen numerosos diseños de distinta complejidad, se presentan algunos problemas que requieren atención y estudio, especialmente en lo que se refiere a la tecnología de secaderos en convección natural. En el presente trabajo se detallan los aspectos constructivos de un tendalero adaptado para funcionar como secadero solar pasivo con una chimenea solar incorporad...

  15. Tratamiento del paciente con artrosis

    OpenAIRE

    Vargas Negrín, Francisco; María D. Medina Abellán; Hermosa Hernán, Juan Carlos; de Felipe Medina, Ricardo

    2014-01-01

    El manejo terapéutico del paciente con artrosis tiene como objetivo disminuir la sintomatología dolorosa e inflamatoria, mejorar la capacidad funcional del paciente y la aplicación de intervenciones terapéuticas eficaces y lo más seguras posibles. Un enfoque centrado en el paciente implica su participación activa en el diseño del plan terapéutico y en la toma de decisiones informadas oportunas en todas las etapas de la enfermedad. La educación terapéutica, la actividad física y el ejercicio t...

  16. FloCon 2011 Proceedings

    Science.gov (United States)

    2011-01-01

    C.COJ81.lJ"’tP ..PTP ·F~~ ,_ ... ...., • ... C.:o....Pl.JIX.J!T$1 ! lr ’~· ""il l’f<lil; e..lo’.ol l .. St:ru ’"’ ·--s.,, ... ,J’too ’~.&o...Biggest advantage: a single parser for IPFIX 4 Using Flow For Other Things Than Network DataFloCon2011 SNMP versus IPFIX  SNMP = poll, IPFIX = push

  17. RASGOS DE PERSONALIDAD EN PACIENTES CON OBESIDAD

    OpenAIRE

    Alejandra Bravo Del Toro; Tania Espinosa Rodríguez; Laura Nancy Mancilla Arroyo; Mariana Tello Recillas

    2011-01-01

    El presente estudio analizó los rasgos de personalidad con mayor incidencia en una población mexicana con obesidad. Se distinguieron los rasgos que intervienen en el funcionamiento diario de los sujetos. La muestra estuvo conformada por 60 pacientes: 31 hombres y 29 mujeres, con edades de 30 a 40 años, casados, con nivel educativo básico y que acudían a consulta médica en un centro de diagnóstico clínico, con antecedentes de obesidad. Se utilizó el perfil-inventario de la personalidad de Gord...

  18. ENERGY GENERATION EXPANSION PLANNING MODEL CONSIDERING EMISSIONS CONSTRAINTS

    Directory of Open Access Journals (Sweden)

    DIEGO ADOLFO MEJIA GIRALDO

    2010-01-01

    Full Text Available El problema de expansión de la generación consiste en determinar el tipo de tecnología, dimensionamiento, ubicación y momento en el cual nuevas plantas de generación deben ser integradas al sistema, en un horizonte de planeamiento dado, para satisfacer la demanda de energía pronosticada. En los últimos años, debido a un creciente interés en asuntos medioambientales, varias metodologías para resolver el problema de expansión de la generación han incluido algún tipo de política medioambiental, típicamente basada en restricciones de emisiones. Este artículo presenta un modelo lineal en una versión dinámica para resolver el problema de planeamiento de expansión de la generación. La principal diferencia entre el modelo propuesto y la mayoría de los trabajos presentados en la literatura especializada es la forma en que la política medioambiental ha sido contemplada. Tal política incluye: i impuestos sobre las emisiones de CO2, ii una reducción anual de emisiones en todo el sistema y iii el retiro gradual de plantas de generación ineficientes. El modelo propuesto ha sido aplicado al caso de expansión de los Estados Unidos para encontrar el portafolio de energía más rentable y sostenible en los próximos 20 años, considerando 11 regiones y 10 tipos diferentes de tecnología.

  19. Preliminary Report on the Effect of Pre-Boring on the Mobilized Friction Capacity of Pile Foundation Hydraulically Jacked into Expansive Soil

    OpenAIRE

    Budi G.S.

    2015-01-01

    Pre-drilling was performed to reduce lateral earth pressure generated by pile foundation hydraulically jacked into expansive soil. Nineteen prestressed-precast spun concrete pile with diameter of 800 mm were penetrated into expansive soil up the depth of 40 m. Pre-drilling with diameter of 700 mm was carried out up to the depth of 12.5 m. Penetration loads required to install the piles, which was displayed on the built-in pressure panel, were recorded every 1 m interval. The load that was con...

  20. Expansion by regions: revealing potential and Glauber regions automatically

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, Bernd [RWTH Aachen University, Institut fuer Theoretische Teilchenphysik und Kosmologie, Aachen (Germany); Smirnov, Alexander V. [Moscow State University, Scientific Research Computing Center, Moscow (Russian Federation); KIT, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany); Smirnov, Vladimir A. [Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); KIT, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany)

    2012-09-15

    When performing asymptotic expansions using the strategy of expansion by regions, it is a non-trivial task to find the relevant regions. The recently published Mathematica code asy.m automates this task, but it has not been able to detect potential regions in threshold expansions or Glauber regions. In this work we present an algorithm and its implementation in the update asy2.m which also reveals potential and Glauber regions automatically. (orig.)

  1. Anisotropic thermal expansion in crystals of different categories

    Science.gov (United States)

    Zamkovskaya, A.; Maksimova, E.

    2015-12-01

    The three-dimensional (3D) indicatory surfaces of thermal expansion in crystals of different categories were constructed in program MathCad. Indicatory surface of thermal expansion is a sphere, spheroid, ellipsoid or surface of multiple parts, depending on the category of the crystal symmetry. The symmetry elements of thermal expansion include the symmetry elements of the point group of the crystal according Neumann's Principle.

  2. Effect of rapid maxillary expansion on sleep characteristics in children

    OpenAIRE

    Navya Ashok; N. K. Sapna Varma; Ajith, V. V.; Siby Gopinath

    2014-01-01

    Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and a...

  3. Orthopedic Treatment of Maxillary Expansion: A Review of the Literature

    OpenAIRE

    Sylvia Ng; Minjie Li; Yanqi Yang

    2015-01-01

    Transverse maxillary deficiency, no matter in adolescents or in adults, is frequently seen in the patients seeking orthodontic treatment. The treatment goal of detaching the midpalatal suture can be achieved using an expansion device. In present article we give a review on various palatal expansion appliances and treatment protocol. A comprehensive search of the literatures was performed to observe the regime of different maxillary expansion appliances and therapies.

  4. Flow in axisymmetric expansion in a catalytic converter

    OpenAIRE

    Gotfredsen, Erik; Meyer, Knud Erik

    2017-01-01

    The flow in an axisymmetric expansion (circular diffusor) is used in many different engineering applications, such as heat exchangers, catalytic converters and filters. These applications require a relatively uniform flow at the inlet. To minimise the pressure loss, an ideal solution would be to use a quite long expansion, but this is often not possible due to space restrictions. Therefore a short expansion combined with e.g. guide vanes is often used. The present study will use a Selective C...

  5. Series expansions of rotating two and three dimensional sound fields.

    Science.gov (United States)

    Poletti, M A

    2010-12-01

    The cylindrical and spherical harmonic expansions of oscillating sound fields rotating at a constant rate are derived. These expansions are a generalized form of the stationary sound field expansions. The derivations are based on the representation of interior and exterior sound fields using the simple source approach and determination of the simple source solutions with uniform rotation. Numerical simulations of rotating sound fields are presented to verify the theory.

  6. Does query expansion limit our learning? A comparison of social-based expansion to content-based expansion for medical queries on the internet.

    Science.gov (United States)

    Pentoney, Christopher; Harwell, Jeff; Leroy, Gondy

    2014-01-01

    Searching for medical information online is a common activity. While it has been shown that forming good queries is difficult, Google's query suggestion tool, a type of query expansion, aims to facilitate query formation. However, it is unknown how this expansion, which is based on what others searched for, affects the information gathering of the online community. To measure the impact of social-based query expansion, this study compared it with content-based expansion, i.e., what is really in the text. We used 138,906 medical queries from the AOL User Session Collection and expanded them using Google's Autocomplete method (social-based) and the content of the Google Web Corpus (content-based). We evaluated the specificity and ambiguity of the expansion terms for trigram queries. We also looked at the impact on the actual results using domain diversity and expansion edit distance. Results showed that the social-based method provided more precise expansion terms as well as terms that were less ambiguous. Expanded queries do not differ significantly in diversity when expanded using the social-based method (6.72 different domains returned in the first ten results, on average) vs. content-based method (6.73 different domains, on average).

  7. Tratamiento del paciente con artrosis

    Directory of Open Access Journals (Sweden)

    Francisco Vargas Negrín

    2014-01-01

    Full Text Available El manejo terapéutico del paciente con artrosis tiene como objetivo disminuir la sintomatología dolorosa e inflamatoria, mejorar la capacidad funcional del paciente y la aplicación de intervenciones terapéuticas eficaces y lo más seguras posibles. Un enfoque centrado en el paciente implica su participación activa en el diseño del plan terapéutico y en la toma de decisiones informadas oportunas en todas las etapas de la enfermedad. La educación terapéutica, la actividad física y el ejercicio terapéutico junto con el control de peso, en caso de sobrepeso u obesidad, constituyen el núcleo central del tratamiento. Los autocuidados individuales y por los familiares son fundamentales en el control del día a día del paciente. El uso de terapias físicas, ayudas técnicas (bastón, etc. y de fármacos tipo analgésicos simples, opioides y antiinflamatorios tiene evidencias demostradas en el control del dolor, mejora la funcionalidad y la calidad de vida del paciente y una clara recomendación de uso en el tratamiento de la artrosis. La cirugía conservadora y la de reemplazo articular se indican en los casos en los que no se logran los objetivos terapéuticos en casos concretos.

  8. Food irradiation - pros and cons

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    The use of ionising radiation for food preservation is a much-disputed topic, both among experts and among consumers. Pros and cons of this issue were discussed in detail at the consumers' forum. Professor Dr. Johannes Friedrich Diehl, Director of the Institute for Biochemistry of the Food Research Centre, Karlsruhe, is a well-known supporter of the new method of food preservation; he sees advantages in the radiopreservation of food because, for example, losses due to inedibility are reduced, the danger of salmonellosis is decreased, just as the use of chemicals. He thinks this method to be without danger to health, shown by many years of experience. Opponents to food irradiation like Prof. Dr. Konrad Pfeilsticker, Professor for food science and food chemistry at the Bonn University deem the method to be unnecessary and raise the problem of qualitative changes caused in the food. In the course of the discussions, the pros and cons seemed to balance each other out.

  9. Conversaciones con Eduardo Ibarra Colado

    Directory of Open Access Journals (Sweden)

    Luis Porter Galetar

    2014-01-01

    Full Text Available Este artículo narra, en forma intimista y coloquial, el contexto en el que dos amigos y colaboradores universitarios integran un grupo de trabajo y escriben un libro. El objetivo del libro es curativo, busca recuperar la esperanza, la sensibilidad y el buen humor. Es útil, o intenta serlo, en el sentido de ilustrar con ejemplos algunos procesos de vida por los que pasan los miembros de la planta académica. Puede ser de interés para los que se preocupan por el desarrollo en la carrera de vida, que hoy afecta a la universidad pública mexicana, con un alto promedio de edad, y corre el peligro de convertirse en una universidad de viejos. Aporta ideas sobre formas de recuperar la salud, y, en alguna medida, la juventud. Propone caminos para unir los fragmentos en que se ha quebrado la universidad y tomar conciencia de la importancia de estar conectados entre nosotros, como una comunidad inserta en una totalidad mayor, representada por el cosmos.

  10. Expansion of Tubular with Elastomers in Multilateral Wells

    Directory of Open Access Journals (Sweden)

    Md Velden

    2013-06-01

    Full Text Available The use of solid expandable tubular technology during the last decade has focused on solving many challenges in well drilling and delivery including zonal isolation, deep drilling, conservation of hole sizes, etc. not only as pioneered solution but also providing cost effective and long lasting solutions. Concurrently, the technology was extended for construction of multilateral in typical wells. The process of horizontal tubular expansion is similar to the vertical expansion of expandable tubular in down-hole environment with the addition of uniformly distributed force due to its weight. The expansion is targeted to increase its diameter such that post expansion characteristics remain within allowable limits. In this study a typical expandable tubular of 57.15 mm outer diameter and 6.35 mm wall thickness was used with two different elastomer seals of 5 and 7 mm thickness placed at equal spacing of 200 mm. The developed stress contours during expansion process clearly showed the high stress areas in the vicinity of expansion region which lies around the mandrel. These high stresses may result in excessive wear of the mandrel. It was also found out that the drawing force increases as the mandrel angle, expansion ratio, and friction coefficient increases. A mandrel angle of 20o  requires minimum expansion force and can be considered as an optimum geometrical parameter to lower the power required for expansion.

  11. 3D automatic expansion: clinical application; L`expansion 3D automatique: application clinique

    Energy Technology Data Exchange (ETDEWEB)

    Gaboriaud, G.; Pontvert, D.; Rosenwald, J.C. [Institut Curie, 75 - Paris (France)

    1998-09-01

    The determination of the various volumes (GTV: gross target volume, CTV: clinical target volume, PTV: planned target volume) recommended by the ICRU 50 report is a critical step in conformal treatment planning, since treatment optimisation procedures and documentation rely on accurate dose-volume histograms. The shape and the size of the CTV vary with the computer algorithm, the patient image acquisition parameters, the definition of the GTV and the margins surrounding it. The automatic expansion programs included in commercially available treatment planning system require careful validation and control before and during their routine use by the clinicians. Significant differences have been observed between 2D- and 3D-based expansions, with a usual underestimation of the PTV by 2D algorithms. (author)

  12. Human expansion precipitates niche expansion for an opportunistic apex predator (Puma concolor).

    Science.gov (United States)

    Moss, Wynne E; Alldredge, Mathew W; Logan, Kenneth A; Pauli, Jonathan N

    2016-12-23

    There is growing recognition that developed landscapes are important systems in which to promote ecological complexity and conservation. Yet, little is known about processes regulating these novel ecosystems, or behaviours employed by species adapting to them. We evaluated the isotopic niche of an apex carnivore, the cougar (Puma concolor), over broad spatiotemporal scales and in a region characterized by rapid landscape change. We detected a shift in resource use, from near complete specialization on native herbivores in wildlands to greater use of exotic and invasive species by cougars in contemporary urban interfaces. We show that 25 years ago, cougars inhabiting these same urban interfaces possessed diets that were intermediate. Thus, niche expansion followed human expansion over both time and space, indicating that an important top predator is interacting with prey in novel ways. Thus, though human-dominated landscapes can provide sufficient resources for apex carnivores, they do not necessarily preserve their ecological relationships.

  13. Cons ICARUS, TIGER and Fascism

    Directory of Open Access Journals (Sweden)

    Janez Vrečko

    2010-12-01

    Full Text Available Like the scientists of their time, Russian artists in the 1920s considered gravity the central problem – a view which points to the close harmony between modern physics and the avant-garde. It was only with the constructivist movement that the Icarus revolution grasped the principles of the “mobile philosophy” (3.651 which was almost at the same time recognised by modern physics as well. The static view of the world became obsolete, space and time were no longer absolute values. It was necessary to transcend Euclidean geometry, shake off the political ʻshackles on one’s hands’ and surrender to Lisicki’s imaginary space, where “At 2000 metres in the air / there is no more perspective” (Integrals 276.  Kosovel’s Icarus project accorded with Tatlin’s, and both of them accorded with the quintessential aims of the constructivist movement. It is no accident that Kosovel wished to name one of his poetry collections The Dream of Icarus. Poems on the Icarus theme, such as “Cons Icarus”, “Evacuation of the Spirit”, “Eh, Hey”, “A Heart in Alcohol” etc. belong to the group of Kosovel’s conses which follow his “mobile philosophy” (3.650 and “letters growing into space” (Int. 282.  The question “Man, do you want up in the air?” (Int. 128 will remain a question until the moment when man is finally ready to transcend the existing boundary and dive “beyond”. Hence Kosovel’s clear-cut contrast between the “green windows of an illuminated / express on a viaduct”, which moves horizontally and is, like a water current, subject to the earth’s gravity, and “the spirit in space”, whose direction of motion is “the perpendicular of the spirit”, atectonicity. “The spirit burns in space”: fire is an element that knows vertical movement alone, the only one of the elements to outgrow and transcend the earth’s gravity, therefore it is associated with another mythological figure important for

  14. Behaviour of built light construction on expansible clays. Technical of design and rehabilitation

    Directory of Open Access Journals (Sweden)

    Arrieta, L.

    2003-12-01

    Full Text Available The construction pathology of housing built on expansible clays is one of the most requested topics to be investigated in order to obtain solutions mainly in housing of social interest. A vision of the solution alternatives is presented that are being applying in Venezuela and specifically in the cities of Barquisimeto and Coro where the most harmful expansion characteristics are presented registered in the world literature. This population is located to the north of the country in front of the Caribbean Sea with arid climate, deep phreatic level, appreciable loamy profile and water deficit. The investigation methodology and some proven procedures for the design of foundations in light housings and for the rehabilitation of damaged buildings are supported with the results of the researches on the part of the two authors and their research teams coming from two different Universities and with 20 years of experience in the practical field. 3 cases are illustrated, two of them with historical value in the design of housings of social interest and one of severely affected constructions and actually rehabilitated with success. Finally some practical recommendations are provided to be considered in the elaboration of projects related with the construction of light housings on expansible floors.

    La patología de construcción de viviendas construidas sobre arcillas expansivas constituye uno de los temas más investigados debido a la gran cantidad de casos identificados con fallos, sobre todo en viviendas de interés social. Se presenta una visión de las alternativas de solución que se vienen aplicando en Venezuela y, específicamente, en las ciudades de Barquisimeto y Coro donde se presentan las características de expansión más perjudiciales registradas en la literatura mundial. Esta población está ubicada al norte del país, frente al mar Caribe, con clima árido, nivel freático profundo, perfil arcilloso apreciable y régimen h

  15. Fare astronomia con piccoli telescopi

    CERN Document Server

    Gainer, Michael K

    2007-01-01

    Non sono necessariamente richiesti strumenti mastodontici per produrre risultati scientificamente validi nel campo dell’astronomia. Anche l’astrofilo dotato di un piccolo telescopio, con un diametro di soli 8-9 cm, può contribuire alla scienza del cielo realizzando utili osservazioni del Sole, della Luna, dei pianeti, delle comete, degli asteroidi, delle stelle doppie o variabili, delle nebulose e degli ammassi stellari. Il manuale di M.K. Gainer spiega quale sia la dotazione minima (un piccolo telescopio, un computer, una semplice fotocamera digitale), come utilizzarla, e quali siano le tecniche appropriate da adottare nelle osservazioni. Offre inoltre schemi per interpretare e ridurre i dati raccolti, nonché schede da compilare e da spedire ai centri di raccolta internazionali. Questo libro è il passaporto grazie al quale l’astrofilo può entrare a pieno titolo nel mondo affascinante della scienza astronomica.

  16. Theology and development as capability expansion

    Directory of Open Access Journals (Sweden)

    Séverine Deneulin

    2016-05-01

    Full Text Available For the last 25 years, human development has become part of official development discourses. It takes the normative position that the success of policies depends on whether they have expanded human flourishing, or expanded the ‘freedoms’ or ‘capabilities’ people have ‘reason to value’, as Amartya Sen would put it. It emphasises the importance of institutions to facilitate such expansion, and the agency of people to create such institutions. The ability of institutions to be conducive to human flourishing depends on the nature of human interaction. When human interaction no longer has the flourishing of other persons as its aim, it can create structures which then constrain human agency. The article argues that the human development perspective could be enriched by theological insights such as structural sin and the contribution of religious narratives to public reasoning. It concentrates on the idea of justice of one biblical parable, and illustrates its argument with examples from the Argentine labour context.

  17. The optimizied expansion method for wavefield extrapolation

    KAUST Repository

    Wu, Zedong

    2013-01-01

    Spectral methods are fast becoming an indispensable tool for wave-field extrapolation, especially in anisotropic media, because of its dispersion and artifact free, as well as highly accurate, solutions of the wave equation. However, for inhomogeneous media, we face difficulties in dealing with the mixed space-wavenumber domain operator.In this abstract, we propose an optimized expansion method that can approximate this operator with its low rank representation. The rank defines the number of inverse FFT required per time extrapolation step, and thus, a lower rank admits faster extrapolations. The method uses optimization instead of matrix decomposition to find the optimal wavenumbers and velocities needed to approximate the full operator with its low rank representation.Thus,we obtain more accurate wave-fields using lower rank representation, and thus cheaper extrapolations. The optimization operation to define the low rank representation depends only on the velocity model, and this is done only once, and valid for a full reverse time migration (many shots) or one iteration of full waveform inversion. Applications on the BP model yielded superior results than those obtained using the decomposition approach. For transversely isotopic media, the solutions were free of the shear wave artifacts, and does not require that eta>0.

  18. Technology portfolio and capacity expansion under uncertainty

    Science.gov (United States)

    Filomena, Tiago Pascoal

    We analyze the problem of generation capacity expansion and portfolio of technologies choice in a restructured electricity market in which marginal costs are uncertain. In our investment model, firms behave as Cournot players and they make three different decisions in equilibrium: (i) the portfolio of technologies, (ii) technologies capacity and (iii) technologies production for every scenario. The decisions related to the portfolio and capacity are ex-ante and the production is ex-post to the realization of uncertainty. We consider the marginal cost as the uncertain parameter and we show with a simple transformation that the model is also flexible to allow for general load curves. Our main result is that portfolio diversification arises even with risk-neutral firms and technologies with different cost expectations. Furthermore, we characterize the production level of each firm for each possible scenario realization. All the conditions that yield (or do not yield) to diversification in a duopoly with two scenarios are discussed in the dissertation. Under our assumptions, we point out that in aggregate terms firms always invest and produce the same quantities. Asymmetry on the use of technologies between players can occur, but it just happens when technologies have the same cost expectation. We show that when technologies present different cost expectation the equilibrium results are unique and symmetric.

  19. Survivial Strategies in Bacterial Range Expansions

    Science.gov (United States)

    Frey, Erwin

    2014-03-01

    Bacterial communities represent complex and dynamic ecological systems. Different environmental conditions as well as bacterial interactions determine the establishment and sustainability of bacterial diversity. In this talk we discuss the competition of three Escherichia coli strains during range expansions on agar plates. In this bacterial model system, a colicin E2 producing strain C competes with a colicin resistant strain R and with a colicin sensitive strain S for new territory. Genetic engineering allows us to tune the growth rates of the strains and to study distinct ecological scenarios. These scenarios may lead to either single-strain dominance, pairwise coexistence, or to the coexistence of all three strains. In order to elucidate the survival mechanisms of the individual strains, we also developed a stochastic agent-based model to capture the ecological scenarios in silico. In a combined theoretical and experimental approach we are able to show that the level of biodiversity depends crucially on the composition of the inoculum, on the relative growth rates of the three strains, and on the effective reach of colicin toxicity.

  20. Medicaid Expansion: A Tale of Two Governors.

    Science.gov (United States)

    Flagg, Robin

    2016-10-01

    This is a study of why two seemingly similar governors made divergent decisions on expanding Medicaid under the Patient Protection and Affordable Care Act (ACA). Performing a case study of Governors John Kasich (OH) and Scott Walker (WI), I explore the roles played by electoral pressures, political party, governor's ideology, the state's policy heritage, stakeholder advocacy, and the economy in each governor's decision about whether to expand Medicaid. Electoral pressure was the most significant factor for both governors. I demonstrate that even Walker succumbed to state electoral pressures and expanded Medicaid, albeit in a manner unique to Wisconsin. He did this despite his emphatic national rhetoric rejecting Obamacare and expansion. Additionally, existing state political institutions drove each governor to decide in a manner unique to his state: previous Medicaid decisions in Wisconsin and direct democracy in Ohio provided additional pressures and divergent starting points. The remaining factors served less as a driving force behind the decision and more as a frame to justify the decision ex post facto. Case studies allow for a more complex view of how political pressures fit together; differences can be explained and expanded, and an enhanced understanding of political processes can be gleaned. Copyright © 2016 by Duke University Press.

  1. Semiquantum chaos and the large N expansion

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, F.; Habib, S.; Kluger, Y. [Los Alamos National Lab., NM (United States); Dawson, J.; Meredith, D.; Shepard, H. [New Hampshire Univ., Durham, NH (United States). Dept. of Physics

    1994-06-29

    When a classical oscillator is interacting with a purely quantum mechanical oscillator, described by the Lagrangian L = 1/2 x{sup 2} + 1/2A{sup 2} - 1/2 (m{sup 2} + e{sup 2} A{sup 2})x{sup 2}, where A is a classical variable and x is a quantum operator the relevant degrees of freedom for the quantum oscillator when {l_angle}x(t)x(t){r_angle} = G(t). The classical Hamiltonian dynamics governing the variables A(t). {Pi}{sub A}(t). G(t) and {Pi}{sub G}(t) is chaotic so that the results of making measurements on the quantum system at later times are sensitive to initial conditions. We review this system and discuss how this behavior is altered when the quantum fluctuations of the A oscillator are determined exactly and in a 1/N expansion where N is the number of copies of the x oscillator.

  2. [Feedback control mechanisms of plant cell expansion

    Energy Technology Data Exchange (ETDEWEB)

    Cosgrove, D.J.

    1992-01-01

    We have generated considerable evidence for the significance of wall stress relaxation in the control of plant growth and found that several agents (gibberellin, light, genetic loci for dwarf stature) influence growth rate via alteration of wall relaxation. We have refined our methods for measuring wall relaxation and, moreover, have found that wall relaxation properties bear only a distance relationship to wall mechanical properties. We have garnered novel insights into the nature of cell expansion mechanisms by analyzing spontaneous fluctuations of plant growth rate in seedlings. These experiments involved the application of mathematical techniques for analyzing growth rate fluctuations and the development of new instrumentation for measuring and forcing plant growth in a controlled fashion. These studies conclude that growth rate fluctuations generated by the plant as consequence of a feedback control system. This conclusion has important implications for the nature of wall loosening processes and demands a different framework for thinking about growth control. It also implies the existence of a growth rate sensor.

  3. Progesterone induces adult mammary stem cell expansion.

    Science.gov (United States)

    Joshi, Purna A; Jackson, Hartland W; Beristain, Alexander G; Di Grappa, Marco A; Mote, Patricia A; Clarke, Christine L; Stingl, John; Waterhouse, Paul D; Khokha, Rama

    2010-06-10

    Reproductive history is the strongest risk factor for breast cancer after age, genetics and breast density. Increased breast cancer risk is entwined with a greater number of ovarian hormone-dependent reproductive cycles, yet the basis for this predisposition is unknown. Mammary stem cells (MaSCs) are located within a specialized niche in the basal epithelial compartment that is under local and systemic regulation. The emerging role of MaSCs in cancer initiation warrants the study of ovarian hormones in MaSC homeostasis. Here we show that the MaSC pool increases 14-fold during maximal progesterone levels at the luteal dioestrus phase of the mouse. Stem-cell-enriched CD49fhi cells amplify at dioestrus, or with exogenous progesterone, demonstrating a key role for progesterone in propelling this expansion. In aged mice, CD49fhi cells display stasis upon cessation of the reproductive cycle. Progesterone drives a series of events where luminal cells probably provide Wnt4 and RANKL signals to basal cells which in turn respond by upregulating their cognate receptors, transcriptional targets and cell cycle markers. Our findings uncover a dynamic role for progesterone in activating adult MaSCs within the mammary stem cell niche during the reproductive cycle, where MaSCs are putative targets for cell transformation events leading to breast cancer.

  4. Testing option pricing with the Edgeworth expansion

    Science.gov (United States)

    Balieiro Filho, Ruy Gabriel; Rosenfeld, Rogerio

    2004-12-01

    There is a well-developed framework, the Black-Scholes theory, for the pricing of contracts based on the future prices of certain assets, called options. This theory assumes that the probability distribution of the returns of the underlying asset is a Gaussian distribution. However, it is observed in the market that this hypothesis is flawed, leading to the introduction of a fudge factor, the so-called volatility smile. Therefore, it would be interesting to explore extensions of the Black-Scholes theory to non-Gaussian distributions. In this paper, we provide an explicit formula for the price of an option when the distributions of the returns of the underlying asset is parametrized by an Edgeworth expansion, which allows for the introduction of higher independent moments of the probability distribution, namely skewness and kurtosis. We test our formula with options in the Brazilian and American markets, showing that the volatility smile can be reduced. We also check whether our approach leads to more efficient hedging strategies of these instruments.

  5. Can snowshoe hares control treeline expansions?

    Science.gov (United States)

    Olnes, Justin; Kielland, Knut; Juday, Glenn P; Mann, Daniel H; Genet, Hélène; Ruess, Roger W

    2017-10-01

    Treelines in Alaska are advancing in elevation and latitude because of climate warming, which is expanding the habitat available for boreal wildlife species, including snowshoe hares (Lepus americanus). Snowshoe hares are already present in tall shrub communities beyond treeline and are the main browser of white spruce (Picea glauca), the dominant tree species at treeline in Alaska. We investigated the processes involved in a "snowshoe hare filter" to white spruce establishment near treeline in Denali National Park, Alaska, USA. We modeled the pattern of spruce establishment from 1970 to 2009 and found that fewer spruce established during periods of high hare abundance. Multiple factors interact to influence browsing of spruce, including the hare cycle, snow depth and the characteristics of surrounding vegetation. Hares are abundant at treeline and may exclude spruce from otherwise optimal establishment sites, particularly floodplain locations with closed shrub canopies. The expansion of white spruce treeline in response to warming climate will be strongly modified by the spatial and temporal dynamics of the snowshoe hare filter. © 2017 by the Ecological Society of America.

  6. Oil sector expansion hits small road bump

    Energy Technology Data Exchange (ETDEWEB)

    Budd, G.

    2002-04-01

    Indications are that the upward production trend in Saskatchewan's oil industry, evident in recent years, will be reversed in 2002. Predictions are that the drop in production will be a modest one, reflecting the slower economy and the lag time between drilling activity and produced barrels of oil. Also a contributing factor is the fact that the year 2001 marked a decline of 20 per cent in oil well drilling from the previous year, down from 2,401 wells drilled to 1,931 wells. Expansions of last year such as PanCanadian's carbon dioxide project, Husky Energy's heavy oil project at Pike's Peak, northeast of Lloydminster, PanCanadian's SAGD project, Conoco's project at the Kerrobert Pool and Apache Canada's Midale area project southeast of Regina, are all likely to see more modest development during 2002. Similar retrenchment is expected at Nexen's (Wascana) Williston Basin area operations, due in part to the increased drilling cost resulting from the intense activity during 2001, and a 5 to 10 per cent rise in operating costs.

  7. Modeling the expansion of a contactor plasma

    Science.gov (United States)

    Hogan, E. A.; Delzanno, G.; Camporeale, E.; Borovsky, J. E.; MacDonald, E.; Thomsen, M. F.

    2012-12-01

    Plasma contactor technology is widely used on board spacecraft to keep spacecraft charging levels under control. On the International Space Station, for instance, it is used to prevent high current discharges between differently charged surfaces. It consists of emitting a neutral plasma to create a plasma reservoir near the spacecraft in order to balance the currents collected by the spacecraft from the magnetospheric environment. One approach to modeling the contactor plasma plume applies a self-similar solution in order to gain insight into the plume dynamics without requiring expensive numerical simulations [1, 2]. Typically, hydrodynamic fluid equations are used to model the plasma behavior. We present a comparison of different self-similar plume models existing in the literature [1, 2] and compare these with our Particle-In-Cell simulations in the near-field to assess their validity. We will consider both the unmagnetized and the magnetized limit, treating the magnitude and angle (relative to the plasma injection velocity) of the magnetic field as a parameter. [1] F. F. Gabdullin, A. G. Korsun, E. M. Tverdokhlebova, 'The plasma plume emitted onboard the international space station under the effect of the geomagnetic field', IEEE Trans. Plasma Science 36(5) 2207 (2008). [2] M. Merino, E. Ahedo, C. Bombardelli, H. Urrutxua, J. Pelaez, 'Hypersonic plasma plume expansion in space', 32nd International Electric Propulsion Conference, IEPC-2011-086, Wiesbaden, Germany, 2011.

  8. Harmonious Expansion of China's Higher Education: A New Growth Pattern

    Science.gov (United States)

    Gu, Jiafeng

    2012-01-01

    How can one country narrow the regional disparity during the tremendous expansion of higher education? This issue remains unexamined and critical analysis is needed to unveil the spatial dynamics behind expansion of higher education. The spatial analysis shows that there is significant strategic interaction among neighboring provinces in China…

  9. Analysis of Factors Influencing Agritourism Businesses in Expansion

    OpenAIRE

    Jensen, Kimberly; Bruch Leffew, Megan; Menard, Jamey; English, Burton C.

    2014-01-01

    This study assesses how characteristics of agritourism operations may influence future expansion plans. Differences in barriers which agritourism operations face, as well as types of promotion methods used are examined for expansion-minded agritourism operators. This information will be useful to agritourism operators, as they look for contributors to future growth.

  10. STABILIZATION OF EXPANSIVE SOIL USING BAGASSE ASH & LIME

    African Journals Online (AJOL)

    tekimerry

    (MDD) and plasticity of the soil for all additives. But there was also a tremendous improvement in the CBR value when the soil is stabilized with a combination of lime and bagasse ash. This shows a potential of using bagasse ash as admixture in lime stabilized expansive soil. Keywords: Expansive soil, bagasse ash, lime,.

  11. Impact of size and temperature on thermal expansion of nanomaterials

    Indian Academy of Sciences (India)

    A theoretical method has been discussed to study the size dependency of thermal expansion of nanomaterials at higher temperature by considering the surface effect. A thermodynamical analysis of the equation of state (EoS) is studied from the knowledge of thermal expansion of nano-materials based on theoretical ...

  12. Did the Higgs boson drive the universe's expansion?

    CERN Multimedia

    2008-01-01

    The Higgs boson has been moonlighting. Not content with its day job of giving other particles their mass, it may also have driven the expansion of the early universe, given a little tinkering, according to two separate studies. Soon after the big bang the early universe is believed to have undergone a period of rapid expansion, known as inflation.

  13. Implementation of centrifuge testing of expansive soils for pavement design.

    Science.gov (United States)

    2017-03-01

    The novel centrifuge-based method for testing of expansive soils from project 5-6048-01 was implemented into : use for the determination of the Potential Vertical Rise (PVR) of roadways that sit on expansive subgrades. The : centrifuge method was mod...

  14. Studies of Expansive Learning: Foundations, Findings and Future Challenges

    Directory of Open Access Journals (Sweden)

    Yrjö Engeström

    2013-07-01

    Full Text Available The paper examines studies based on the theory of expansive learning, formulated in 1987. In recent years the theory has been used in a wide variety of studies and interventions. The theory builds on foundational ideas put forward by Vygotsky, Leont’ev, Il’enkov, and Davydov, key figures in the Russian school of cultural-historical activity theory. Studies based on the theory are reviewed in six sections: expansive learning as transformation of the object, expansive learning as movement in the zone of proximal development, expansive learning as cycles of learning actions, expansive learning as boundary crossing and network building, expansive learning as distributed and discontinuous movement, and formative interventions.A separate section is devoted to critiques of expansive learning. It is concluded that the ultimate test of learning theories is how they help practitioners to generate learning that grasps pressing issues the humankind is facing. The theory of expansive learning currently expands its analyses both up and down, outward and inward. Moving up and outward, it tackles learning in fields or networks of interconnected activity systems with their partially shared and often contested objects. Moving down and inward, it tackles issues of subjectivity, experiencing, personal sense, emotion, embodiment, identity, and moral commitment.

  15. Clusters of Organic Molecules in a Supersonic Jet Expansion

    NARCIS (Netherlands)

    Jonkman, Harry T.; Even, Uzi; Kommandeur, Jan

    1985-01-01

    A wide variety of clusters were obtained in seeded supersonic conical jet expansions of organic molecules. It was shown that mixed clusters probably are formed statistically in the collisional region of the expansion, although kinetic effects cannot be excluded. The molecular fragmentation in the

  16. Shrub expansion in SW Greenland under modest regional warming

    DEFF Research Database (Denmark)

    Jørgensen, Rasmus Halfdan; Meilby, Henrik; Kollmann, Johannes

    2013-01-01

    Shrub expansion has been observed widely in tundra areas across the Arctic. This phenomenon has been partially attributed to increasing temperatures over the past century. However, relationships among shrub expansion, grazing, and human disturbance have been studied little. SW Greenland is a suba...

  17. Dynamics of plasma expansion in the pulsed laser material interaction

    Indian Academy of Sciences (India)

    process results from the anisotropic expansion velocities associated with different species. These velocities are mainly controlled by the initial dimension of the expanding plasma. An attempt was undertaken to estimate the length of the plume at different ambient gas pressures using an adiabatic expansion model. The rate.

  18. Surgical Splint Design Influences Transverse Expansion in Segmental Maxillary Osteotomies

    DEFF Research Database (Denmark)

    Stokbro, Kasper; Aagaard, Esben; Torkov, Peter

    2017-01-01

    Purpose: In segmental maxillary procedures, it is imperative to obtain as much of the planned expansion as possible. Lack of obtained expansion, in addition to late relapse after splint removal, can result in relapse of the posterior crossbite. This study investigated the influence of 2 surgical ...

  19. Expansion of U. S. uranium enrichment capacity. Final environmental statement

    Energy Technology Data Exchange (ETDEWEB)

    1976-04-01

    Reasonably foreseeable environmental, social, economic, and technological costs and benefits of postulated expansion of U. S. enrichment capacity through the year 2000 and reasonably available alternatives to such expansion are described. Both the gas centrifuge and gaseous diffusion methods for the enrichment of uranium are considered in this impact assessment. (JGB)

  20. 1 INVESTIGATIONS ON THE EXPANSIVE SOILS OF ADDIS ABABA ...

    African Journals Online (AJOL)

    group comprises of basic igneous rocks. Here feldspar and pyroxene minerals of the parent rocks decompose to form montmorillonite - the predominant mineral of expansive soil - and other secondary minerals. The second group comprises of sedimentary rocks that contain montmorillonite. The expansive soils of Ethiopia ...

  1. Higher Education in Ethiopia: Expansion, Quality Assurance and Institutional Autonomy

    Science.gov (United States)

    Akalu, Girmaw Abebe

    2014-01-01

    This article chronicles the key challenges facing Ethiopia as it embarks on an ambitious, ideologically-driven and aggressive expansion of its higher education system in an effort to address its national goals of economic growth and poverty reduction. It is argued that the urge for higher education expansion has placed undue pressures particularly…

  2. 12 CFR 34.84 - Future bank expansion.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Future bank expansion. 34.84 Section 34.84 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.84 Future bank expansion. A national bank normally should use real...

  3. Asymptotic expansions for high-contrast linear elasticity

    KAUST Repository

    Poveda, Leonardo A.

    2015-03-01

    We study linear elasticity problems with high contrast in the coefficients using asymptotic limits recently introduced. We derive an asymptotic expansion to solve heterogeneous elasticity problems in terms of the contrast in the coefficients. We study the convergence of the expansion in the H1 norm. © 2015 Elsevier B.V.

  4. 14 CFR 29.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 29.969 Section 29.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Fuel System § 29.969 Fuel tank expansion space...

  5. 14 CFR 27.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 27.969 Section 27.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Fuel System § 27.969 Fuel tank expansion space...

  6. 14 CFR 25.969 - Fuel tank expansion space.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 25.969 Section 25.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant Fuel System § 25.969 Fuel tank expansion space...

  7. Electric Grid Expansion Planning with High Levels of Variable Generation

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, Stanton W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); You, Shutang [Univ. of Tennessee, Knoxville, TN (United States); Shankar, Mallikarjun [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Yilu [Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-02-01

    Renewables are taking a large proportion of generation capacity in U.S. power grids. As their randomness has increasing influence on power system operation, it is necessary to consider their impact on system expansion planning. To this end, this project studies the generation and transmission expansion co-optimization problem of the US Eastern Interconnection (EI) power grid with a high wind power penetration rate. In this project, the generation and transmission expansion problem for the EI system is modeled as a mixed-integer programming (MIP) problem. This study analyzed a time series creation method to capture the diversity of load and wind power across balancing regions in the EI system. The obtained time series can be easily introduced into the MIP co-optimization problem and then solved robustly through available MIP solvers. Simulation results show that the proposed time series generation method and the expansion co-optimization model and can improve the expansion result significantly after considering the diversity of wind and load across EI regions. The improved expansion plan that combines generation and transmission will aid system planners and policy makers to maximize the social welfare. This study shows that modelling load and wind variations and diversities across balancing regions will produce significantly different expansion result compared with former studies. For example, if wind is modeled in more details (by increasing the number of wind output levels) so that more wind blocks are considered in expansion planning, transmission expansion will be larger and the expansion timing will be earlier. Regarding generation expansion, more wind scenarios will slightly reduce wind generation expansion in the EI system and increase the expansion of other generation such as gas. Also, adopting detailed wind scenarios will reveal that it may be uneconomic to expand transmission networks for transmitting a large amount of wind power through a long distance

  8. Micro-architected Composite Lattices with Tunable Negative Thermal Expansions

    Science.gov (United States)

    Wang, Qiming

    Solid materials with minimum or negative thermal expansion (NTE) have broad applications, from dental fillings to thermal-sensitive precision instruments. Previous studies on NTE structures were mostly focused on theoretically design and 2D experimental demonstrations. Here, aided with multimaterial projection micro-stereolithography, we experimentally fabricate multi-material composite lattices that exhibit significant negative thermal expansion in three directions and over a large range of temperature variations. The negative thermal expansion is induced by the structural interaction of material components with distinct thermal expansion coefficients. The NTE performance can be tuned over a large range by varying the thermal expansion coefficient difference between constituent beams and geometrical arrangement. Our experimental results match qualitatively with a simple scaling law and quantitatively consistently with computational models.

  9. Bubble motion in sudden expansion in vertical pipe flow

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Koichi [Marine Technical College, Ashiya, Hyogo (Japan); Yoshida, Kenji; Matsumoto, Tadayoshi; Okawa, Tomio; Kataoka, Isao [Osaka Univ., Suita, Osaka (Japan)

    2002-07-01

    Experimental studies were made on the multi-dimensional behavior of upward gas-liquid two-phase flow through the vertical round tube with an axisymmetric sudden expansion, which is one of the typical multi-dimensional channel geometry. The direct observation using high-speed video camera was performed and revealed the multi-dimensional dynamic flow behavior affected by the sudden expansion. Characteristic phenomena were observed such as bubble break-up, deformation due to the strong share of liquid flow, or liquid micro jet penetration through the gas-slug, and so on. From these results, the flow regime map at the below or above of the sudden expansion part was classified. The phase distributions in sudden expansion were also showed in detail that how the two-phase flow develops along the direction of the downstream of the sudden expansion. (J.P.N.)

  10. Assessing thesaurus-based query expansion using the UMLS Metathesaurus.

    Science.gov (United States)

    Hersh, W; Price, S; Donohoe, L

    2000-01-01

    Assess query expansion using thesaurus relationships and definitions in the UMLS Metathesaurus for improving searching performance. The queries from a MEDLINE test collection (OHSUMED) were expanded using synonym, hierarchical, and related term information as well as term definitions from the UMLS Metathesaurus. Documents were retrieved from a word-statistical retrieval system and assessed for recall and precision based on relevance judgments from the test collection. All types of query expansion degraded aggregate retrieval performance as measured by recall and precision, although 38.6% of the queries with synonym expansion and up to 29.7% of the queries with hierarchical expansion showed improvement. Thesaurus-based query expansion causes a decline in retrieval performance generally but improves it in specific instances. Further research must focus on identifying instances where performance improves and how it can be exploited by real users.

  11. Tratamiento conservador en pacientes con retinoblastoma bilateral

    OpenAIRE

    Juan C. Suárez; Mabel C. Ospina; Sandra A. Arias; María E. González

    2008-01-01

    OBJETIVO: comparar el tratamiento convencional del retinoblastoma bilateral, usado hasta hace algunos años, consistente en radioterapia o enucleación bilateral, con el tratamiento conservador actual que incluye termoterapia transpupilar (TTT) o TTT/quimioterapia al menos en un ojo, en niños con diagnóstico de retinoblastoma bilateral. DISEÑO: estudio retrospectivo descriptivo. MUESTRA: 20 pacientes con diagnóstico de retinoblastoma bilateral que consultaron al Hospital Universitario San Vicen...

  12. A Meta-Analysis of Global Urban Land Expansion

    Science.gov (United States)

    Seto, Karen C.; Fragkias, Michail; Güneralp, Burak; Reilly, Michael K.

    2011-01-01

    The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km2 from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km2 and 12,568,000 km2, with an estimate of 1,527,000 km2 more likely. PMID:21876770

  13. Expansion of IFC model with structural sensors

    Directory of Open Access Journals (Sweden)

    Rio, J.

    2013-06-01

    Full Text Available The instrumentation and structural health monitoring, SHM, of buildings is a growing field in the construction industry. The goal of this research work is to explore ways of modeling SHM systems, and the resulting data collected from buildings, in standard information management system such as Building Information Models, BIM. These models need to be stored in digital databases with structures suitable for the specific building related information. In this work the Industry Foundation Classes, IFC, data model was used. A case study is presented to assess the applicability of the present IFC standard as a tool to build a three-dimensional digital model of a real instrumented building, as well as some of the structural sensors and their results. The interoperability of the digital model was verified by using different modeling, viewing and analysis software tools. Limitations of the current IFC model were explored and extensions to the sensor classes are proposed.La instrumentación y monitorización de la salud estructural de edificios, SHM, es un campo creciente en la industria de la construcción. El objetivo del presente trabajo es estudiar la modelación de sistemas SHM tomados de edificios en un modelo digital BIM e la sua integración de datos. Estos modelos deben almacenarse en bases de datos con una estructura apropiada para albergar información específica relacionada con la construcción. En este trabajo se utilizó el estándar Industry Foundation Classes, IFC. Se presenta un estudio de caso para evaluar la norma IFC como herramienta para modelar un edificio real instrumentado, así como algunos sensores estruturales e sus resultados. La inter-operatividad de lo modelo digital se ha comprobado mediante el uso de diferentes herramientas de software de modelación, visualización y análisis. Se exploran además limitaciones del modelo IFC y se proponen extensiones de las clases de sensores.

  14. Reconocimiento de actividad mediante pulsera con sensores

    OpenAIRE

    Aguilera Calle, Iván; García Moreno, Daniel; Morante Pindado, Verónica; Pidal Gallego, Alejandro

    2017-01-01

    Desde hace unos años, con el desarrollo de los smartphones y actualmente con el auge del internet de las cosas, la tecnología ha invadido gran parte de nuestra vida como en campos de la salud, el deporte o el bienestar. Este trabajo se centra en los dos últimos aspectos con el fin de hacer una app para smartphone de reconocimiento de actividad mediante sensores, con el que se busca conseguir que las personas lleven un control de las actividades que hacen a lo largo del día, pudiendo tener un ...

  15. Criptococosis diseminada en anciano con VIH

    National Research Council Canada - National Science Library

    Escobar, Ana Maria; Diaz, Ricardo; Posada, Alfredo

    2011-01-01

    Se presenta un paciente masculino de 79 anos con un cuadro clinico de sintomas constitucionales, asociado a pleuresia linfocitica, meningitis e hidrocefalia, confirmandose posteriormente criptococosis...

  16. Criptococosis gingival en un paciente con SIDA

    OpenAIRE

    Delgado-Azañero, Wilson A.; Facultad de Estomatología, Universidad Peruana Cayetano Heredia. Lima; Meneses Rivadeneyra, Leopoldo; Facultad de Estomatología, Universidad Peruana Cayetano Heredia. Lima,; Gotuzzo Herencia, Eduardo; Instituto de Medicina Tropical “Alexander von Humboldt”. Universidad Peruana Cayetano Heredia. Lima,; Bustamante, Beatriz; Instituto de Medicina Tropical “Alexander von Humboldt”. Universidad Peruana Cayetano Heredia. Lima,

    2014-01-01

    La criptococosis es una infección micótica que afecta a personas con o sin inmunosupresión. Sepresenta principalmente como una infección pulmonar crónica. La mayoría de casos enmucosa oral han sido reportados en pacientes con SIDA que cursaban con la forma diseminadade la infección. Se presenta un paciente varón de 36 años con SIDA, cuyo diagnóstico decriptococosis se estableció por biopsias de las encías. El cuadro oral se caracterizó poragrandamientos gingivales del sector ántero superior e...

  17. Mejorando la planificación de sistemas territoriales con optimización metaheurística

    Directory of Open Access Journals (Sweden)

    Roger Z. Ríos Mercado

    2015-01-01

    Full Text Available Este artículo tiene por objetivo ilustrar cómo la ciencia puede impactar positivamente en procesos de decisiones de carácter industrial. El problema consiste en encontrar una partición del conjunto total de unidades geográficas (bloques que minimice una única función de dispersión territorial. Esta medida de desempeño es equivalente a maximizar la compacidad de los territorios, es decir, obtener diseños donde ls unidades geográficas estén lo más cercanas entre sí. La solución debe satisfacer además otros requerimientos como equilibrar las distintas medidas de actividad entre los distintos territorios, así como contigüidad de territorios. Como resultado se tiene un modelo mono-objetivo de optimización combinatoria. Método: Para tal efecto, se presenta un método metaheurístico de solución, denominado GRASP, para la resolución de un problema de diseño de territorios comerciales, motivado por una aplicación real de una compañía de distribución de bebidas embotelladas. El método integra componentes de construcción de soluciones y de búsqueda local o mejora de las mismas que intentan explotar inteligentemente la estructura matemática del problema. Resultados: El algoritmo se ha evaluado en varios conjuntos de instancias generados aleatoriamente a partir de datos reales proporcionados por el socio industrial. Los resultados obtenidos indican la eficacia del método propuesto dado que, en tiempos de cómputo relativamente rápidos, pudieron obtenerse soluciones de calidad muy superior a la de las obtenidas por la empresa, tanto respecto a la medida de compacidad, como respecto a la satisfacción de todas las restricciones. Previo a abordar el trabajo, la empresa no podía encontrar solcuiones que satisfacieran grados de balence, por ejemplo, inferiores al 20%. EL método propuesto encuentra siempre soluciones factibles con desbalances menores al 5%. Conclusión: Se ha ilustrado cómo los problemas de toma de decisiones

  18. 78 FR 2952 - Foreign-Trade Zone 3-San Francisco, California; Application for Expansion and Expansion of...

    Science.gov (United States)

    2013-01-15

    ... Foreign-Trade Zones Board Foreign-Trade Zone 3--San Francisco, California; Application for Expansion and Expansion of Service Area Under Alternative Site Framework An application has been submitted to the Foreign..., 10/20/2010). The zone project currently has a service area that includes the City and County of San...

  19. Myocardial infarct expansion, infarct extension, and reinfarction: pathophysiologic concepts.

    Science.gov (United States)

    Weisman, H F; Healy, B

    1987-01-01

    Infarct expansion and infarct extension are events early in the course of myocardial infarction with serious short- and long-term consequences. Infarct expansion, disproportionate thinning, and dilatation of the infarct segment probably begin within hours of acute infarction and usually reach peak extent within seven to 14 days. Clinical data suggest that infarct expansion occurs in approximately 35% to 45% of anterior transmural myocardial infarctions and to a lesser extent in infarctions at other sites. Although expansion usually develops in large infarcts, the extent of transmural necrosis rather than absolute infarct size predicts its occurrence. Expansion has an adverse effect on infarct structure and function for several reasons. Functional infarct size is increased because of infarct segment lengthening, and expansion results in over-all ventricular dilatation. Thus, patients with expansion of an infarct have poorer exercise tolerance, more congestive heart failure symptoms, and greater early and late mortality than those without expansion. Infarct rupture and late aneurysm formation are two additional structural consequences of infarct expansion. Experimental and clinical data suggest that the incidence and severity of expansion can be modified by interventions. Increased ventricular loading conditions and steroidal and nonsteroidal antiinflammatory agents make expansion more severe. Reperfusion of the infarct segment and pharmacologic interventions that decrease ventricular afterload lessen the severity of expansion. Previous myocardial infarction and preexisting ventricular hypertrophy may also limit the development of infarct expansion. Infarct extension is defined clinically as early in-hospital reinfarction after a myocardial infarction. The pathologic finding of infarct extension is necrotic and healing myocardium of several different recent ages within the same vascular territory. Although this pathologic criterion usually cannot be verified, studies

  20. Optimal expansion planning of stand-alone systems with stochastic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Hoese, Alejandro [Instituto de Energia Electrica (IEE), Universidad Nacional de San Juan, (Argentina)

    1997-12-31

    Stand-alone systems in the range of 1 kW - 10 MW are taking relevance in the new (global) liberal concept of energy market. State and private investors are becoming increasingly attention on the use of renewable for these systems, but it must be shown that these non-conventional solutions are competitive with the established conventional ones. The high investment costs and the technical and economic uncertainties coupled with the use of time-dependent energy sources are the mainly inhibiting factors for the decision agents to choose these systems instead of conventional ones. In the paper a new model for optimal expansion planning of hybrid stand-alone generating systems under consideration of uncertainties is presented. This model is at present in {sup d}evelopment state{sup .} Results already obtained in the first steps of this research are promising and some of them are here presented. [Espanol] Los sistemas autocontenidos en el rango de 1 Kw a 10 MW estan tomando importancia en el nuevo (global) concepto liberal del mercado de la energia. Inversionistas privados y del Estado estan poniendo mayor atencion en el uso de energias renovables para estos sistemas, pero debe mostrarse que estas soluciones no-convencionales son competitivas con las convencionales establecidas. Los altos costos de inversion y las incertidumbres tecnicas y economicas aunadamente con el uso de fuentes de energia dependientes del tiempo son los principales factores inhibidores de los factores de decision para escoger estos sistemas en lugar de los convencionales. En este articulo se presenta un nuevo modelo de planeacion de expansion optima de sistemas hibridos autocontenidos de generacion electrica bajo la consideracion de incertidumbres. Este modelo esta actualmente en {sup e}stado de desarrollo{sup .} Los resultados ya obtenidos en las primeras etapas de esta investigacion son prometedores y se presentan algunos de ellos.

  1. Adiciones y cementos con adiciones

    Directory of Open Access Journals (Sweden)

    Calleja, José

    1983-09-01

    Full Text Available The present paper deals with aspects concerning the conditions to be fulfilled by raw materials and manufacturing process of cements containing components other than clinker and setting regulator. It deals also with proper conditions for the utilization of these cements, as well as with the knowledge of the interrelation between manufacture and use of them, in order to aid the manufacturers and the users in the better profit o such energy saving blended cements in optimal technical and economical conditions.

    Se tratan en este trabajo aspectos relativos a las condiciones exigibles a las materias primas y a los procesos de fabricación de los cementos que contienen constituyentes distintos del clínker y del yeso. Se tienen también en cuenta las condiciones adecuadas para utilizar estos cementos, así como el conocimiento de las relaciones entre la fabricación y el empleo de los cementos con constituyentes secundarios que ahorran energía, a fin de ayudar a fabricantes y usuarios en su mejor aprovechamiento en condiciones técnicas y económicas óptimas.

  2. Plantas cubanas con efecto antiinflamatorio

    Directory of Open Access Journals (Sweden)

    Ada Ivis Regalado Veloz

    Full Text Available La actividad antiinflamatoria suscita gran interés científico en el área farmacológica, debido a que muchas enfermedades en su evolución cursan por procesos inflamatorios (artritis reumatoide, ateroesclerosis, cáncer, diabetes, gota, asma, dermatitis, trastornos neurodegenerativos y diversas dolencias menores. Las enfermedades inflamatorias constituyen un problema de salud importante, debido a la falta de medicamentos eficaces y seguros para su uso por periodos prolongados. Hoy en día se trabaja en la búsqueda de alternativas de antiinflamatorios más seguros, en el que las plantas medicinales, una de las formas más antiguas de tratamiento, constituyen una elección a considerar. En este trabajo se realizó una revisión bibliográfica, sobre especies de plantas que crecen en Cuba que le reportan propiedades farmacológicas como antinflamatorios. En la revisión de la literatura se utilizó la base de datos Medline (vía PubMed, así como revistas nacionales desde el periodo de 2000 hasta el presente, con las palabras claves "inflamación" y "plantas cubanas antiinflamatorias" o "actividad antiinflamatoria" y "plantas medicinales".

  3. Itinerari Musicali con la Wiild

    Directory of Open Access Journals (Sweden)

    Elisabetta Nanni

    2013-03-01

    Full Text Available La Wiild, acronimo di Wiimote Lavagna Digitale, è uno strumento didattico che utilizza il telecomando della Wii, il famoso gioco della Nintendo, insieme a un software libero, rendendolo così estremamente versatile. Non vincolato a software proprietario, il suo utilizzo è legato alla capacità dell’insegnante di ripartire dalla didattica, dalle risorse selezionate e dall’epistemologia di ogni singola disciplina, trovando così nel proprio contesto un ruolo per le tecnologie. Il contributo presenta ipotesi di lavoro per l’educazione musicale nella scuola secondaria di primo grado che si sviluppano sia attraverso lo studio del rapporto suono/segno con affinità pittoriche e successiva codificazione grafica, sia attraverso un’attività di laboratorio in cui co-costruire percorsi storico-musicali. La Wiild diventerà davvero utile ed efficace nel momento in cui, affiancando le risorse selezionate dal docente, verrà utilizzata senza essere notata, giocando un ruolo di strumento tecnologico «normale e trasparente».

  4. Hospitalidad, con y sin papeles

    Directory of Open Access Journals (Sweden)

    Ana Paula Penchaszadeh

    Full Text Available Resumen El objetivo de este artículo es vincular el trabajo sobre el archivo de Jacques Derrida con la experiencia de la hospitalidad. Se intentará mostrar que, por un lado, se trata siempre de los papeles, de la legitimidad que éstos otorgan o no tanto a nivel filosófico (deseo de poseer los papeles que autoricen tal o cual decisión interpretativa, como a nivel político ("tener papeles" como el principio básico de todo derecho a tener derechos, de todo derecho a la comunidad. Mas también, por otro lado, se intentará pensar aquello que arruina la idea misma de tener o no tener (papeles, la idea de propiedad, aquello que hace imposible fundar una decisión o identidad en última instancia y, por ende, una soberanía, una frontera. La hospitalidad, la llegada inminente del otro, representa un desafío político y ético para la filosofía: pues no se trata de un saber, sino de una experiencia transformando el sustrato del nos-otros, del ser común.

  5. Variacion del nivel de citoquinas en liquido sinovial de equinos con enfermedad articular tratados con bisfosfonatos

    National Research Council Canada - National Science Library

    Polli, Magali; Caggiano, Nicolas; Rolando, Jesica; Perrone, Gustavo; Marino, Mario; De Simone, Emilio; Chiappe, Barbara Angelina

    2013-01-01

    .... El diagnostico precoz de esta enfermedad, que en ocasiones no es factible con estudios radiograficos, deviene en la posibilidad de realizar un tratamiento temprano con el objeto de evitar mayor...

  6. Estado oxidativo en gatas suplementadas con aceite de pescado y desafiadas con acetaminofen

    National Research Council Canada - National Science Library

    Constanza Gonzalez, Iris; Noro, Mirela; Sebastian Galecio, Juan; Chihuailaf, Ricardo; Wittwer, Fernando

    2013-01-01

    El objetivo del estudio fue evaluar el balance energetico y oxidativo en gatas suplementadas con aceite de pescado y determinar la presencia de dano oxidativo posterior a un desafio con acetaminofen...

  7. La atencion a los padres con hijos con necesidades educativas especiales

    National Research Council Canada - National Science Library

    Pernas Pico, Claudia Maria

    2011-01-01

    Los padres que tienen hijos con necesidades educativas especiales (NEE) necesitan al igual que sus hijos de la intervencion del maestro de Audicion y Lenguaje con el objetivo primordial de mejorar la comunicacion y el lenguaje de los ninos...

  8. Future urban land expansion and implications for global croplands.

    Science.gov (United States)

    Bren d'Amour, Christopher; Reitsma, Femke; Baiocchi, Giovanni; Barthel, Stephan; Güneralp, Burak; Erb, Karl-Heinz; Haberl, Helmut; Creutzig, Felix; Seto, Karen C

    2017-08-22

    Urban expansion often occurs on croplands. However, there is little scientific understanding of how global patterns of future urban expansion will affect the world's cultivated areas. Here, we combine spatially explicit projections of urban expansion with datasets on global croplands and crop yields. Our results show that urban expansion will result in a 1.8-2.4% loss of global croplands by 2030, with substantial regional disparities. About 80% of global cropland loss from urban expansion will take place in Asia and Africa. In both Asia and Africa, much of the cropland that will be lost is more than twice as productive as national averages. Asia will experience the highest absolute loss in cropland, whereas African countries will experience the highest percentage loss of cropland. Globally, the croplands that are likely to be lost were responsible for 3-4% of worldwide crop production in 2000. Urban expansion is expected to take place on cropland that is 1.77 times more productive than the global average. The loss of cropland is likely to be accompanied by other sustainability risks and threatens livelihoods, with diverging characteristics for different megaurban regions. Governance of urban area expansion thus emerges as a key area for securing livelihoods in the agrarian economies of the Global South.

  9. Effect of rapid maxillary expansion on sleep characteristics in children

    Directory of Open Access Journals (Sweden)

    Navya Ashok

    2014-01-01

    Full Text Available Introduction: Rapid maxillary expansion (RME is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB. Aims and Objectives: The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Materials and Methods: Polysomnography was done on children of 8-13 years of age before expansion (T0, after expansion (T1 and after a period of 3 months after retention (T2. Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Statistical Analysis: Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2. Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2. P < 0.05 were considered as significant. Results: All children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Conclusions: Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination.

  10. Effect of rapid maxillary expansion on sleep characteristics in children.

    Science.gov (United States)

    Ashok, Navya; Varma, N K Sapna; Ajith, V V; Gopinath, Siby

    2014-10-01

    Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB). The main objective of this study was to evaluate the effects of RME on sleep characteristics in children. Polysomnography was done on children of 8-13 years of age before expansion (T0), after expansion (T1) and after a period of 3 months after retention (T2). Bonded rapid maxillary expander was cemented in all children. Inter-molar distance was also measured at T0 and T2. Nonparametric Friedman test was used for comparing the averages of sleep parameters at different time period (T0, T1, T2). Wilcoxon signed ranks test was used for comparing the averages of inter-molar width (T0-T2). P children showed an improvement in sleep parameters with an increase in sleep efficiency, decreased in arousal and desaturation index after expansion. Total sleep time showed a statistically significant increase after expansion. A statistically significant increase in inter-molar distance was obtained after expansion. Rapid maxillary expansion is a useful treatment option for improving quality of sleep even in normal children without SDB. It also induces widening of the maxilla, corrects posterior crossbites and improves maxillary and mandibular dental arch coordination.

  11. Controlling Thermal Expansion: A Metal–Organic Frameworks Route

    Science.gov (United States)

    2016-01-01

    Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal–organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host–guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion. PMID:28190918

  12. Controlling Thermal Expansion: A Metal-Organic Frameworks Route.

    Science.gov (United States)

    Balestra, Salvador R G; Bueno-Perez, Rocio; Hamad, Said; Dubbeldam, David; Ruiz-Salvador, A Rabdel; Calero, Sofia

    2016-11-22

    Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal-organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host-guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion.

  13. The [epsilon] expansion and the electroweak phase transition

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, P.; Yaffe, L.G. (Department of Physics, University of Washington, Seattle, Washington 98195 (United States))

    1994-03-15

    Standard perturbative (or mean field theory) techniques are not adequate for studying the finite-temperature electroweak phase transition in some cases of interest to scenarios for electroweak baryogenesis. We instead study the properties of this transition using the renormalization group and the [epsilon] expansion. This expansion, based on dimensional continuation from 3 to 4--[epsilon] spatial dimensions, provides a systematic approximation for computing the effects of (near-)critical fluctuations. The [epsilon] expansion is known to predict a first-order transition in Higgs theories, even for heavy Higgs boson masses. The validity of this conclusion in the standard model is examined in detail. A variety of physical quantities are computed at leading and next-to-leading order in [epsilon]. For moderately light Higgs boson masses (below 100 GeV), the [epsilon] expansion suggests that the transition is more strongly first order than is predicted by the conventional analysis based on the one-loop (ring-improved) effective potential. Nevertheless, the rate of baryon nonconservation after the transition is found to be [ital larger] than that given by the one-loop effective potential calculation. Detailed next-to-leading order calculations of some sample quantities suggests that the [epsilon] expansion is reasonably well behaved for Higgs boson masses below 100--200 GeV. We also compare the [epsilon] expansion with large-[ital N] results (where [ital N] is the number of scalar fields) and find that the [epsilon] expansion is less well behaved in this limit.

  14. Asymptotic expansions for high-contrast elliptic equations

    KAUST Repository

    Calo, Victor M.

    2014-03-01

    In this paper, we present a high-order expansion for elliptic equations in high-contrast media. The background conductivity is taken to be one and we assume the medium contains high (or low) conductivity inclusions. We derive an asymptotic expansion with respect to the contrast and provide a procedure to compute the terms in the expansion. The computation of the expansion does not depend on the contrast which is important for simulations. The latter allows avoiding increased mesh resolution around high conductivity features. This work is partly motivated by our earlier work in [Domain decomposition preconditioners for multiscale flows in high-contrast media, Multiscale Model Simul. 8 (2010) 1461-1483] where we design efficient numerical procedures for solving high-contrast problems. These multiscale approaches require local solutions and our proposed high-order expansion can be used to approximate these local solutions inexpensively. In the case of a large-number of inclusions, the proposed analysis can help to design localization techniques for computing the terms in the expansion. In the paper, we present a rigorous analysis of the proposed high-order expansion and estimate the remainder of it. We consider both high-and low-conductivity inclusions. © 2014 World Scientific Publishing Company.

  15. Spatial and Temporal Dimensions of Urban Expansion in China.

    Science.gov (United States)

    Zhao, Shuqing; Zhou, Decheng; Zhu, Chao; Sun, Yan; Wu, Wenjia; Liu, Shuguang

    2015-08-18

    The scale of urbanization in China during the past three decades is unprecedented in human history, and the processes are poorly understood. Here we present an effort to map the urban land expansion processes of 32 major cities in China from 1978 to 2010 using Landsat satellite data to understand the temporal and spatial characteristics. Results showed that the urban extent of the 32 cities expanded exponentially with very high annual rates varying from 3.2% to 12.8%. Temporal fluctuation in urban expansion rates in these 32 cities was obvious, with unexpected and alarming expansion rates from 2005 to 2010 that drastically exceeded their expectation, which was calculated from the long-term trend between 1978 and 2005, by 45%. Overall, we found that the growth rates of cities during the entire study period were inversely related to city size, contradicting the theory or Gibrat's law, which states that the growth rate is independent of city size. More detailed analysis indicated that city growth in China has transitioned from contradicting to conforming to Gibrat's law since 1995. Our study suggests that the urban expansion theory (i.e., Gibrat's law) does not fit Chinese expansion consistently over time, and the exact causes are unknown. Exploring the causes in future research will improve our understanding of the theory and, more importantly, understand the feasibility of the theoretical relationship between city size and expansion rate in guiding contemporary urban expansion planning.

  16. Evolution of density-dependent movement during experimental range expansions.

    Science.gov (United States)

    Fronhofer, E A; Gut, S; Altermatt, F

    2017-12-01

    Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  17. MULTIPLE ANT COLONY SYSTEM FOR A VRP WITH TIME WINDOWS AND SCHEDULED LOADING MÚLTIPLES SISTEMAS DE COLONIAS DE HORMIGAS PARA UN VRP CON VENTANAS DE TIEMPO Y PROGRAMACIÓN DE LA CARGA

    Directory of Open Access Journals (Sweden)

    Pablo Ortega

    2009-12-01

    Full Text Available The vehicle routing problem with time windows and scheduled loading [VRPTWSL] requires not only the design of routes with time windows and capacity constraints, but also a schedule of the departures of vehicles from the depot given a load time due to the limited resources available to load the demand in the vehicles. A mathematical formulation of the vehicle routing problem with time windows and scheduled loading is presented and a metaheuristics based on Multiple Ant Colony System is proposed and implemented where two ant colonies, each with a single objective function, are organized in a hierarchical way. A time update procedure is incorporated into the ant constructive procedure to update and schedule the departure of a vehicle from the depot when each ant moves to a new customer-node. Constraint programming is used to determine a feasible move to a new customer-node. As [VRPTWSL] incorporates the vehicle departure scheduling, the algorithm presented in this paper has a direct application to real problems, in this way [VRPTWSL] can be taken as an important advance for practical vehicle routing problems.El problema de rutas para vehículos con ventanas de tiempo y programación de la carga no solo requiere el diseño de las rutas que satisfagan las restricciones temporales y de capacidad de los vehículos sino que también la programación de las salidas de los vehículos desde un terminal dado un tiempo de carga debido a los recursos limitados disponibles para cargar las demandas de los clientes en los vehículos. No solo se presenta una formulación del problema de diseño de rutas para vehículos con ventanas de tiempo y programación de la carga, sino que también se propone e implementa una metaheurística basada en múltiples sistemas de colonias de hormigas, cada una con una sola función objetivo, organizadas de manera jerárquica. Se incorpora una forma de actualización de tiempo dentro del procedimiento constructivo para actualizar

  18. Evaluation on expansive performance of the expansive soil using electrical responses

    Science.gov (United States)

    Chu, Ya; Liu, Songyu; Bate, Bate; Xu, Lei

    2018-01-01

    Light structures, such as highways and railroads, built on expansive soils are prone to damages from the swelling of their underlain soil layers. Considerable amount of research has been conducted to characterize the swelling properties of expansive soils. Current swell characterization models, however, are limited by lack of standardized tests. Electrical methods are non-destructive, and are faster and less expensive than the traditional geotechnical methods. Therefore, geo-electrical methods are attractive for defining soil characteristics, including the swelling behavior. In this study, comprehensive laboratory experiments were undertaken to measure the free swelling and electrical resistivity of the mixtures of commercial kaolinite and bentonite. The electrical conductivity of kaolinite-bentonite mixtures was measured by a self-developed four-electrode soil resistivity box. Increasing the free swelling rate of the kaolinite-bentonite mixtures (0.72 to 1 of porosity of soils samples) led to a reduction in the electrical resistivity and an increase in conductivity. A unique relationship between free swelling rate and normalized surface conductivity was constructed for expensive soils by eliminating influences of porosity and m exponent. Therefore, electrical response measurement can be used to characterize the free swelling rate of expensive soils.

  19. Expansion plan of the electrical sector; Plan de expansion del sector electrico

    Energy Technology Data Exchange (ETDEWEB)

    Cristerna Ocampo, Rafael [Comision Federal de Electricidad (Mexico)

    1996-07-01

    An analysis of the Mexican electrical market in the year 1994 as far as sales of electrical energy and types of users who utilized that energy, is presented. In addition, an analysis is made of the options for the future supply, where the installed electrical capacity in Mexico in 1994 is described. Also the requirements of additional capacity of power generation, from year 1995 to year 2004 are analyzed. In the internal supply of primary energy in Mexico, the hydrocarbons represent 83%, the diversified sources (nuclear, geothermal, hydro and coal) represent 7% and the biomass as well as complementary coal, the 10% balance of the primary energy. Finally an expansion plan of the transmission network of the Mexican electrical system is described. [Spanish] Se presenta un analisis del mercado electrico mexicano en el ano de 1994 en cuanto a ventas de energia electrica y los tipos de usuarios que utilizaron esa energia. Se hace un analisis ademas, de las opciones para la oferta futura, donde se describe la capacidad electrica instalada de Mexico en 1994. Tambien se analizan los requerimientos de capacidad adicional de generacion de 1995 al 2004. En la oferta interna de energia primaria en Mexico, los hidrocarburos representan el 83%, las fuentes diversificadas (nuclear, geotermia, hidro y carboelectrica) representan el 7% y la biomasa asi como el carbon complementario, el 10% restante de la energia primaria. Finalmente se describe un plan de expansion de la red de transmision del sistema electrico mexicano.

  20. Evaluating expansion strategies for startup European Union dairy farm businesses.

    Science.gov (United States)

    McDonald, R; Shalloo, L; Pierce, K M; Horan, B

    2013-06-01

    A stochastic whole-farm simulation model was used to examine alternative strategies for new entrant dairy farmers to grow and develop dairy farm businesses in the context of European Union (EU) milk quota abolition in 2015. Six alternative strategies were compared: remain static, natural growth expansion, waiting until after EU milk quota abolition to expand, a full-scale expansion strategy without milk quotas and not incurring super levy penalties, a full-scale expansion strategy with milk quotas and incurring super levy penalties, and once-a-day milking until EU milk quota abolition, followed by full-scale expansion. Each discrete whole farm investment strategy was evaluated over a 15-yr period (2013-2027) using multiple financial stability and risk indicators, including overall discounted farm business profitability, net worth change, return on investment, and financial risk. The results of this study indicate that, although associated with increased risk, dairy farm expansion will ensure the future profitability of the farm business. Within the context of EU milk quotas until 2015, the most attractive expansion strategy is to increase cow numbers while avoiding super levy fines using once-a-day milking techniques, increasing to the full capacity of the dairy farm once milk quotas are removed. In contrast, the results also indicate that dairy farms that remain static will experience a significant reduction in farm profitability in the coming year due to production cost inflation. Cash flow deficits were observed during the initial year of expansion and, therefore, rapidly expanding dairy farm businesses require a significant cash reserve to alleviate business risk during the initial year of expansion. The results of this analysis also indicate that dairy farm businesses that expand using lower cost capital investments and avoid milk quota super levy fines significantly reduce the financial risks associated with expansion. Copyright © 2013 American Dairy Science

  1. Multiple pathways of commodity crop expansion in tropical forest landscapes

    Science.gov (United States)

    Meyfroidt, Patrick; Carlson, Kimberly M.; Fagan, Matthew E.; Gutiérrez-Vélez, Victor H.; Macedo, Marcia N.; Curran, Lisa M.; DeFries, Ruth S.; Dyer, George A.; Gibbs, Holly K.; Lambin, Eric F.; Morton, Douglas C.; Robiglio, Valentina

    2014-07-01

    Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement

  2. Bases tratadas con cemento, en California

    Directory of Open Access Journals (Sweden)

    Chinchilla, M.

    1962-05-01

    Full Text Available El uso de bases tratadas con cemento para autopistas se inició en el Estado de California en 1938, empleándose para carreteras con determinadas condiciones de tráfico. Inicialmente, se especificó el uso obligatorio de plantas mezcladoras para asegurar el debido control de las proporciones adecuadas.

  3. Arte con lenguaje matemático

    OpenAIRE

    Moratalla de la Hoz, Ascension; Sanz Garcia, Agripina

    2010-01-01

    En este artículo mostramos la experiencia realizada con alumnos de primer curso de la ETSA de la Universidad Politécnica de Madrid, basada en el análisis de obras arquitectónicas y de arte con lenguaje matemático

  4. The Lost Foam method – pre-expansion process

    Directory of Open Access Journals (Sweden)

    T. Pacyniak

    2010-04-01

    Full Text Available In the study, a pre-expansion station, designed by authors, was presented. It consists of a batch pre-expander with a 90 liters capacity foaming chamber, equipped with fluidized-solid dryer of pre-expanded beads and a pneumatic transport system of granules to the silo. Steam is delivered to the pre-expander from the electric vapor generator type LW 40.1. In the study, work principle of the pre-expansion station and pre-expansion tests carried out on this position were presented.

  5. DYN3D thermal expansion models for SFR applications

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, Evgeny; Fridman, Emil [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Div. Reactor Safety

    2016-07-01

    The nodal diffusion code DYN3D is under extension for SFR applications. As a part of the extension a new model for axial thermal expansion of fuel rods was developed. The new model provides a flexible way of handling the axial fuel rod expansion, because each sub-assembly and node can be treated independently. The performance of the model was tested on a large oxide SFR core, and the results were compared to the reference full core Serpent solution. The test results indicated that the proposed model can accurately account for the axial expansion effects on full core level.

  6. Small dead-time expansion in counting distributions and moments

    Science.gov (United States)

    Ackermann, J.; Hogreve, H.

    2010-03-01

    Considering type I counters affected by a dead-time τ, we study the τ expansion of the probabilities and moments of the underlying stochastic renewal process. For the counting distributions and probabilities we extend results from the literature and analyse their approximation properties. Our results show, in particular, that for increasing counting numbers ever larger orders of the τ expansion are required for accurate approximations. Furthermore, the τ expansion for the first and second moments are obtained; their series is proved to coincide with the respective long time asymptotics. This asymptotics is demonstrated to converge exponentially fast to the exact quantities for growing time.

  7. Expansive Learning in Construction Projects - a Contradiction in terms?

    DEFF Research Database (Denmark)

    Klitgaard, Anne; Nissen, Søren Bülow; Beck, Frederikke

    2016-01-01

    This research is a preliminary study performed as part of a primary research into expansive learning in interorganizational network set up to solve a construction project. The construction industry has long had issues about productivity, which can be an indication of lack of learning. A case study...... acquisition and participation but not by expansive learning. The construction industry needs to accept that the learning generated from projects will be limited to learning by acquisition and participation. The interorganizational network cannot facilitate expansive learning while working on object......-fixed projects. Research in construction management fails to generate and document knowledge because of the limitations of case studies....

  8. Edgeworth expansion for the pre-averaging estimator

    DEFF Research Database (Denmark)

    Podolskij, Mark; Veliyev, Bezirgen; Yoshida, Nakahiro

    asymptotic variance. Our approach is based on martingale embedding, Malliavin calculus and stable central limit theorems for continuous diffusions. Moreover, we derive the density expansion for the studentized statistic, which might be applied to construct asymptotic confidence regions.......In this paper, we study the Edgeworth expansion for a pre-averaging estimator of quadratic variation in the framework of continuous diffusion models observed with noise. More specifically, we obtain a second order expansion for the joint density of the estimators of quadratic variation and its...

  9. Chemical Expansion: Implications for Electrochemical Energy Storage and Conversion Devices

    DEFF Research Database (Denmark)

    Bishop, S.R.; Marrocchelli, D.; Chatzichristodoulou, Christodoulos

    2014-01-01

    Many energy-related materials rely on the uptake and release of large quantities of ions, for example, Li+ in batteries, H+ in hydrogen storage materials, and O2− in solid-oxide fuel cell and related materials. These compositional changes often result in large volumetric dilation of the material...... modeling and an overview of factors impacting chemical expansion. We discuss the implications of chemical expansion for mechanical stability and functionality in the energy applications above, as well as in other oxide-based systems. The use of chemical expansion as a new means to probe other materials...

  10. Mechanism of actuation in conducting polymers: Osmotic expansion

    DEFF Research Database (Denmark)

    Bay, Lasse; Jacobsen, Torben; West, Keld

    2001-01-01

    Conducting polymers expand or contract when their redox state is changed. This expansion/contraction effect can be separated in an intrinsic part because of changes of the polymer backbone on reduction/oxidation and a part depending on the surrounding electrolyte phase, because of osmotic expansion...... of the polymer phase. The osmotic effect causes solvent molecules to move into the polymer in a number far in excess of those bound strongly in the solvation shell of the mobile ion, resulting in large volume changes. In this paper, a thermodynamic description of the osmotic expansion is worked out. The model...

  11. Application of the optimum reactive power dispatch to the cost establishment for the support voltage in a power electrical system for generalized dispatch; Aplicacion del despacho optimo de potencia reactiva al establecimiento del costo por el soporte de voltaje en un sistema electrico de potencia con despacho centralizado

    Energy Technology Data Exchange (ETDEWEB)

    Barragan Gomez, Sergio Baruch

    2004-05-15

    de operacion. Por lo tanto existe la necesidad de determinar un costo por el soporte de voltaje de los generadores, ya que esta accion es considerada como un servicio auxiliar y es retribuida de manera independiente. En este trabajo, se utiliza el metodo del gradiente para solucionar el despacho de potencia reactiva y determinar el costo por el soporte de voltaje de cada generador participante en el sistema. El despacho de potencia reactiva esta sujeto a restricciones de igualdad que representan las ecuaciones de balance de potencia activa y reactiva de cada nodo y a restricciones de desigualdad que corresponden a los limites en los perfiles de voltaje de todos los nodos del sistema. Las restricciones de igualdad se consideran dentro del problema de optimizacion con el metodo de los multiplicadores de Lagrange y las restricciones de desigualdad a partir de funciones de penalizacion cuadraticas. El costo total por el soporte de voltaje de cada generador esta formado por un costo fijo y un costo variable. El costo fijo se calcula a partir del factor de recuperacion anual del capital invertido en el generador. El costo variable depende de las condiciones de operacion y del costo por perdida de oportunidad del generador. Para determinar el costo total por el soporte de voltaje de los generadores, se considera que el mercado de potencia activa ya ha sido resuelto con anterioridad a traves de un despacho economico de potencia activa. Los sistemas utilizados para la evaluacion del programa desarrollado son: el sistema de 5 nodos y el sistema de 30 nodos de la IEEE.

  12. Global Grid of Probabilities of Urban Expansion to 2030

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Grid of Probabilities of Urban Expansion to 2030 presents spatially explicit probabilistic forecasts of global urban land cover change from 2000 to 2030...

  13. Observed poleward expansion of the Hadley circulation since 1979

    Directory of Open Access Journals (Sweden)

    Y. Hu

    2007-10-01

    Full Text Available Using three meteorological reanalyses and three outgoing long-wave radiation (OLR datasets, we show that the Hadley circulation has a significant expansion of about 2 to 4.5 degrees of latitude since 1979. The three reanalyses all indicate that the poleward expansion of the Hadley circulation in each hemisphere occurs during its summer and fall seasons. Results from the OLR datasets do not have such seasonality. The expansion of the Hadley circulation implies a poleward expansion of the band of subtropical subsidence, leading to enhanced mid-latitude tropospheric warming and poleward shifts of the subtropical dry zone. This would contribute to an increased frequency of midlatitude droughts in both hemispheres.

  14. Yes and no to grid expansion.; Jein zum Netzausbau.

    Energy Technology Data Exchange (ETDEWEB)

    Huebner, Gundula; Pohl, Johannes [Halle-Wittenberg Univ. (Germany). Inst. fuer Psychologie

    2011-09-15

    The construction of new power plants using renewable energy sources necessitates expansion of power transmission grids. Everyone is in agreement about that, but there is disagreement about the details.

  15. Effect of rapid maxillary expansion on sleep characteristics in children

    National Research Council Canada - National Science Library

    Ashok, Navya; Varma, N K Sapna; Ajith, V V; Gopinath, Siby

    2014-01-01

    Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB...

  16. Effect of rapid maxillary expansion on sleep characteristics in children

    National Research Council Canada - National Science Library

    Navya Ashok; N. K. Sapna Varma; V V Ajith; Siby Gopinath

    2014-01-01

    Introduction: Rapid maxillary expansion (RME) is an orthopedic treatment procedure routinely used to treat constricted maxillary arches and also a potential additional treatment in children presenting with sleep-disordered breathing (SDB...

  17. Seal assembly for materials with different coefficients of thermal expansion

    Science.gov (United States)

    Minford, Eric [Laurys Station, PA

    2009-09-01

    Seal assembly comprising (a) two or more seal elements, each element having having a coefficient of thermal expansion; and (b) a clamping element having a first segment, a second segment, and a connecting segment between and attached to the first and second segments, wherein the two or more seal elements are disposed between the first and second segments of the clamping element. The connecting segment has a central portion extending between the first segment of the clamping element and the second segment of the clamping element, and the connecting segment is made of a material having a coefficient of thermal expansion. The coefficient of thermal expansion of the material of the connecting segment is intermediate the largest and smallest of the coefficients of thermal expansion of the materials of the two or more seal elements.

  18. Geographic Expansion Strategic Model in Iran: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Shahram Yazdani

    2016-12-01

    Conclusion: For promotion of community health and improvement of the national and international position of Iran’s medical universities and HE centers, policymakers should consider the diverse factors that influence HE expansion in our developed model.

  19. The Electroweak Phase Transition, Part 2: $\\epsilon$-Expansion Results

    OpenAIRE

    Yaffe, Laurence

    1994-01-01

    Talk presented at the conference Quarks `94: Vladimir, Russia. I summarize the application of $\\epsilon$-expansion methods to the electroweak phase transition. Results from both leading and next-to-leading order calculations are discussed.

  20. Generation and transmission expansion planning for renewable energy integration

    Energy Technology Data Exchange (ETDEWEB)

    Bent, Russell W [Los Alamos National Laboratory; Berscheid, Alan [Los Alamos National Laboratory; Toole, G. Loren [Los Alamos National Laboratory

    2010-11-30

    In recent years the expansion planning problem has become increasingly complex. As expansion planning (sometimes called composite or integrated resource planning) is a non-linear and non-convex optimization problem, researchers have traditionally focused on approximate models of power flows to solve the problem. The problem has also been split into generation expansion planning (GEP) and transmission network expansion planning (TNEP) to improve computational tractability. Until recently these approximations have produced results that are straight-forward to combine and adapt to the more complex and complete problem. However, the power grid is evolving towards a state where the adaptations are no longer easy (e.g. large amounts of limited control, renewable generation, comparable generation and transmission construction costs) and necessitates new approaches. Recent work on deterministic Discrepancy Bounded Local Search (DBLS) has shown it to be quite effective in addressing the TNEP. In this paper, we propose a generalization of DBLS to handle simultaneous generation and transmission planning.

  1. Linear delta expansion technique for the solution of anharmonic ...

    Indian Academy of Sciences (India)

    The linear delta expansion technique has been developed for solving the differential equation of motion for symmetric and asymmetric anharmonic oscillators. We have also demonstrated the sophistication and simplicity of this new perturbation technique.

  2. Soil Organic Carbon Responses to Forest Expansion on Mountain Grasslands

    DEFF Research Database (Denmark)

    Guidi, Claudia

    Grassland abandonment followed by progressive forest expansion is the dominant land-use change in the European Alps. Contrasting trends in soil organic carbon (SOC) stocks have been reported for mountainous regions following forest expansion on grasslands. Moreover, its effects on SOC properties....... Changes in labile soil C were assessed by carbohydrate and thermal analyses of soil samples and fractions. Forest expansion on mountain grasslands caused a decrease in SOC stocks within the mineral soil. The SOC accumulation within the organic layers following forest establishment could not fully...... involved into long-term stability are largely unknown. The aim of this PhD thesis was to explore changes in: (i) SOC stocks; (ii) physical SOC fractions; and (iii) labile soil carbon components following forest expansion on mountain grasslands. A land-use gradient located in the Southern Alps (Italy...

  3. QUANTUM SPACE AND THE EXPANSION OF THE UNIVERSE

    OpenAIRE

    CARLOS A. MELENDRES

    2017-01-01

    A new quantum model of space  and the evolution of the universe is presented. They provide a a mechanism to explain the accelerated expansion of the universe, dark energy,  and the nature of dark matter.

  4. Negative thermal expansion near two structural quantum phase transitions

    Energy Technology Data Exchange (ETDEWEB)

    Occhialini, Connor A.; Handunkanda, Sahan U.; Said, Ayman; Trivedi, Sudhir; Guzmán-Verri, G. G.; Hancock, Jason N.

    2017-12-01

    Recent experimental work has revealed that the unusually strong, isotropic structural negative thermal expansion in cubic perovskite ionic insulator ScF3 occurs in excited states above a ground state tuned very near a structural quantum phase transition, posing a question of fundamental interest as to whether this special circumstance is related to the anomalous behavior. To test this hypothesis, we report an elastic and inelastic x-ray scattering study of a second system Hg2I2 also tuned near a structural quantum phase transition while retaining stoichiometric composition and high crystallinity. We find similar behavior and significant negative thermal expansion below 100 K for dimensions along the body-centered-tetragonal c axis, bolstering the connection between negative thermal expansion and zero-temperature structural transitions.We identify the common traits between these systems and propose a set of materials design principles that can guide discovery of newmaterials exhibiting negative thermal expansion

  5. Fixed Points of Expansive Type Mappings in 2-Banach Spaces

    Directory of Open Access Journals (Sweden)

    Prabha Chouhan

    2013-08-01

    Full Text Available In present paper, we define expansive mappings in 2-Banach space and prove some common unique fixed point theorems which are the extension of results of Wang et al. [12] and Rhoades [9] in 2-Banach space.

  6. Short interval expansion of Rényi entropy on torus

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Wu, Jun-Bao [Theoretical Physics Division, Institute of High Energy Physics, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Zhang, Jia-ju [Theoretical Physics Division, Institute of High Energy Physics, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China)

    2016-08-23

    We investigate the short interval expansion of the Rényi entropy for two-dimensional conformal field theory (CFT) on a torus. We require the length of the interval ℓ to be small with respect to the spatial and temporal sizes of the torus. The operator product expansion of the twist operators allows us to compute the short interval expansion of the Rényi entropy at any temperature. In particular, we pay special attention to the large c CFTs dual to the AdS{sub 3} gravity and its cousins. At both low and high temperature limits, we read the Rényi entropies to order ℓ{sup 6}, and find good agreements with holographic results. Moreover, the expansion allows us to read 1/c contribution, which is hard to get by expanding the thermal density matrix. We generalize the study to the case with the chemical potential as well.

  7. Expansion coding: Achieving the capacity of an AEN channel

    CERN Document Server

    Koyluoglu, O Ozan; Si, Hongbo; Vishwanath, Sriram

    2012-01-01

    A general method of coding over expansions is proposed, which allows one to reduce the highly non-trivial problem of coding over continuous channels to a much simpler discrete ones. More specifically, the focus is on the additive exponential noise (AEN) channel, for which the (binary) expansion of the (exponential) noise random variable is considered. It is shown that each of the random variables in the expansion corresponds to independent Bernoulli random variables. Thus, each of the expansion levels (of the underlying channel) corresponds to a binary symmetric channel (BSC), and the coding problem is reduced to coding over these parallel channels while satisfying the channel input constraint. This optimization formulation is stated as the achievable rate result, for which a specific choice of input distribution is shown to achieve a rate which is arbitrarily close to the channel capacity in the high SNR regime. Remarkably, the scheme allows for low-complexity capacity-achieving codes for AEN channels, using...

  8. Medicaid Managed Care Penetration Rates and Expansion Enr...

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Medicaid managed care penetration rates and expansion enrollment by state charts are composed annually by the Data and System Group (DSG) of the Centers for...

  9. Compact representation of radiation patterns using spherical mode expansions

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, T.L.; Chen, Yinchao (South Carolina Univ., Columbia, SC (USA). Dept. of Electrical and Computer Engineering)

    1990-07-15

    This report presents the results of an investigation of SM (Spherical Mode) expansions as a compact and efficient alternative to the use of current distributions for generating radiation patterns. The study included three areas: (1) SM expansion from the radiation pattern; (2) SM expansion from the antenna current; and (3) Literature search. SM expansions were obtained from radiation patterns during the initial phase of this study. Although straightforward in principal, however, this technique was found to be awkward for the treatment on theoretical radiation patterns. It is included here for completeness and for possible use to summarize experimental results in a more meaningful way than with an exhaustive display of amplitude with azimuth and elevation angles. In essence, the work in this area served as as warm-up problem to develop our skills in computing and manipulating spherical modes as mathematical entities. 6 refs., 21 figs., 6 tabs.

  10. INVESTIGATION OF HOLOCENE FAULTING PROPOSED C-746-U LANDFILL EXPANSION

    Energy Technology Data Exchange (ETDEWEB)

    Lettis, William [William Lettis & Associates, Inc.

    2006-07-01

    This report presents the findings of a fault hazard investigation for the C-746-U landfill's proposed expansion located at the Department of Energy's (DOE) Paducah Gaseous Diffusion Plant (PGDP), in Paducah, Kentucky. The planned expansion is located directly north of the present-day C-746-U landfill. Previous geophysical studies within the PGDP site vicinity interpret possible northeast-striking faults beneath the proposed landfill expansion, although prior to this investigation the existence, locations, and ages of these inferred faults have not been confirmed through independent subsurface exploration. The purpose of this investigation is to assess whether or not Holocene-active fault displacement is present beneath the footprint of the proposed landfill expansion.

  11. Integrating agricultural expansion into conservation biogeography: conflicts and priorities

    Directory of Open Access Journals (Sweden)

    Ricardo Dobrovolski

    2014-06-01

    Full Text Available Increasing food production without compromising biodiversity is one of the great challenges for humanity. The aims of my thesis were to define spatial priorities for biodiversity conservation and to evaluate conservation conflicts considering agricultural expansion in the 21st century. I also tested the effect of globalizing conservation efforts on both food production and biodiversity conservation. I found spatial conflicts between biodiversity conservation and agricultural expansion. However, incorporating agricultural expansion data into the spatial prioritization process can significantly alleviate conservation conflicts, by reducing spatial correlation between the areas under high impact of agriculture and the priority areas for conservation. Moreover, developing conservation blueprints at the global scale, instead of the usual approach based on national boundaries, can benefit both food production and biodiversity. Based on these findings I conclude that the incorporation of agricultural expansion as a key component for defining global conservation strategies should be added to the list of solutions for our cultivated planet.

  12. Can confidence indicators forecast the probability of expansion in Croatia?

    Directory of Open Access Journals (Sweden)

    Mirjana Čižmešija

    2016-04-01

    Full Text Available The aim of this paper is to investigate how reliable are confidence indicators in forecasting the probability of expansion. We consider three Croatian Business Survey indicators: the Industrial Confidence Indicator (ICI, the Construction Confidence Indicator (BCI and the Retail Trade Confidence Indicator (RTCI. The quarterly data, used in the research, covered the periods from 1999/Q1 to 2014/Q1. Empirical analysis consists of two parts. The non-parametric Bry-Boschan algorithm is used for distinguishing periods of expansion from the period of recession in the Croatian economy. Then, various nonlinear probit models were estimated. The models differ with respect to the regressors (confidence indicators and the time lags. The positive signs of estimated parameters suggest that the probability of expansion increases with an increase in Confidence Indicators. Based on the obtained results, the conclusion is that ICI is the most powerful predictor of the probability of expansion in Croatia.

  13. Rocky Mountain Arsenal Lower Derby Lake shoreline expansion project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this Project Completion Report is to document the completion of the Lower Derby Lake Shoreline Expansion Project and summarize project highlights....

  14. Gateway Arch Circulator Conceptual Feasibility Study : Jefferson National Expansion Memorial

    Science.gov (United States)

    2015-03-01

    The Jefferson National Expansion Memorial (JEFF) is undergoing major design changes as part of the City Arch River 2015 project (CAR) that will impact access for park visitors. The park and stakeholders are considering a circulator system to facilita...

  15. The expansion rate and size of the universe

    CERN Multimedia

    Freedman, Wendy L

    1998-01-01

    The age, evolution and fate of the universe depend on just how fast it is expanding. By measuring the size of the universe using a variety of new techniques, astronomers have recently improved estimates of the expansion rate

  16. Differential cosmic expansion and the Hubble flow anisotropy

    Science.gov (United States)

    Bolejko, Krzysztof; Nazer, M. Ahsan; Wiltshire, David L.

    2016-06-01

    The Universe on scales 01-100 h-1Mpc is dominated by a cosmic web of voids, filaments, sheets and knots of galaxy clusters. These structures participate differently in the global expansion of the Universe: from non-expanding clusters to the above average expansion rate of voids. In this paper we characterize Hubble expansion anisotropies in the COMPOSITE sample of 4534 galaxies and clusters. We concentrate on the dipole and quadrupole in the rest frame of the Local Group. These both have statistically significant amplitudes. These anisotropies, and their redshift dependence, cannot be explained solely by a boost of the Local Group in the Friedmann-Lemaitre-Robertson-Walker (FLRW) model which expands isotropically in the rest frame of the cosmic microwave background (CMB) radiation. We simulate the local expansion of the Universe with inhomogeneous Szekeres solutions, which match the standard FLRW model on gtrsim 100 h-1Mpc scales but exhibit nonkinematic relativistic differential expansion on small scales. We restrict models to be consistent with observed CMB temperature anisotropies, while simultaneously fitting the redshift variation of the Hubble expansion dipole. We include features to account for both the Local Void and the "Great Attractor". While this naturally accounts for the Hubble expansion and CMB dipoles, the simulated quadrupoles are smaller than observed. Further refinement to incorporate additional structures may improve this. This would enable a test of the hypothesis that some large angle CMB anomalies result from failing to treat the relativistic differential expansion of the background geometry; a natural feature of solutions to Einstein's equations not included in the current standard model of cosmology.

  17. Separable Ernst-Shakin-Thaler expansions of local potentials

    Science.gov (United States)

    Bund, Gerhard Wilhelm

    1985-06-01

    The boundary condition Ernst-Shakin-Thaler method, introduced previously to generate separable expansions of local potentials of finite range, is applied to the study of the triplet s-wave Malfliet-Tjon potential. The effect of varying the radius where the boundary condition is applied on the T matrix is analyzed. Further, we compare the convergence of the n-d scattering cross sections in the quartet state below the breakup threshold for expansions corresponding to two different boundaries.

  18. UTD at TREC 2014: Query Expansion for Clinical Decision Support

    Science.gov (United States)

    2014-11-01

    medical knowledge bases, such as the Unified Medical Language System ( UMLS ), the Systemized Nomenclature of Medicine – Clini- cal Terms (SNOMED-CT...System ( UMLS ), the Systemized Nomenclature of Medicine { Clini- cal Terms (SNOMED-CT), and Wikipedia as well as unsupervised distributional representa...following subsections describe the four methods of query expansion that we have considered. UMLS Expansions of fatigue) weariness lack of energy fatigue

  19. Thermal expansion of spinel-type Si3N4

    DEFF Research Database (Denmark)

    Paszkowics, W.; Minkikayev, R.; Piszora, P.

    2004-01-01

    The lattice parameter and thermal expansion coefficient (TEC) for the spinel-type Si3N4 phase prepared under high-pressure and high-temperature conditions are determined for 14 K......The lattice parameter and thermal expansion coefficient (TEC) for the spinel-type Si3N4 phase prepared under high-pressure and high-temperature conditions are determined for 14 K...

  20. Unduland universe: expansion with alternating eras of acceleration and deceleration

    OpenAIRE

    Barenboim Szuchman, Gabriela Alejandra; Mena Requejo, Olga; Quigg, Chris

    2005-01-01

    If the equation of state for "dark energy" varies periodically, the expansion of the Universe may have undergone alternating eras of acceleration and deceleration. We examine a specific form that survives existing observational tests, does not single out the present state of the Universe as exceptional, and suggests a future much like the matter-dominated past: a smooth expansion without a final inflationary epoch.

  1. Transmission Network Expansion Planning Considering Phase-Shifter Transformers

    OpenAIRE

    Miasaki, Celso T.; Franco, Edgar M. C.; Romero, Ruben A.

    2012-01-01

    This paper presents a novel mathematical model for the transmission network expansion planning problem. Main idea is to consider phase-shifter (PS) transformers as a new element of the transmission system expansion together with other traditional components such as transmission lines and conventional transformers. In this way, PS are added in order to redistribute active power flows in the system and, consequently, to diminish the total investment costs due to new transmission lines. Proposed...

  2. Use of Expansion Turbines in Natural Gas Pressure Reduction Stations

    Directory of Open Access Journals (Sweden)

    Poživil Jaroslav

    2004-09-01

    Full Text Available Through the use of expansion turbines in natural gas pressure reduction stations it is possible to produce clean, “green” electricity.Such energy recovery unit utilize the potential energy of natural gas being delivered under high pressure. Expansion turbines are not onlyefficient and profitable but meet the environmental criteria – no emissions of sulfur dioxide, nitrogen oxides or carbon dioxide.

  3. AL-HARM EXPANSION MOVIE BASED ON VIRTUAL REALITY

    OpenAIRE

    Alanoud Salem; Sara Musallam; El-Shaimaa Nada; Ahmed Ahmed

    2015-01-01

    Animated movies are excellent virtual environments for creating models in high quality. Animated movies can include 3D models, sounds and lights effects, and detailed maps. In this paper, a virtual reality movie is applied to Al-Haram Expansion stages including the future stage of expansion. 3DMAX program is used to rich the maximum benefits of using 3D modeling. Maps with details are built by using ARCGIS program in order to understand the real difference between the three dif...

  4. Experimental Test for epsilon-Expansions with n=4

    DEFF Research Database (Denmark)

    Ott, H. R.; Kjems, Jørgen

    1980-01-01

    epsilon (Porson)-expansion calculations predict the magnetic phase transitions of the Ce monochalcogenides to be first order. We present experimental evidence that the transitions in CeSe and CeTe are continuous.......epsilon (Porson)-expansion calculations predict the magnetic phase transitions of the Ce monochalcogenides to be first order. We present experimental evidence that the transitions in CeSe and CeTe are continuous....

  5. Early Medicaid Expansion Associated With Reduced Payday Borrowing In California.

    Science.gov (United States)

    Allen, Heidi; Swanson, Ashley; Wang, Jialan; Gross, Tal

    2017-10-01

    We examined the impact of California's early Medicaid expansion under the Affordable Care Act on the use of payday loans, a form of high-interest borrowing used by low- and middle-income Americans. Using a data set for the period 2009-13 (roughly twenty-four months before and twenty-four months after the 2011-12 Medicaid expansion) that covered the universe of payday loans from five large payday lenders with locations around the United States, we used a difference-in-differences research design to assess the effect of the expansion on payday borrowing, comparing trends in early-expansion counties in California to those in counties nationwide that did not expand early. The early Medicaid expansion was associated with an 11 percent reduction in the number of loans taken out each month. It also reduced the number of unique borrowers each month and the amount of payday loan debt. We were unable to determine precisely how and for whom the expansion reduced payday borrowing, since to our knowledge, no data exist that directly link payday lending to insurance status. Nonetheless, our results suggest that Medicaid reduced the demand for high-interest loans and improved the financial health of American families. Project HOPE—The People-to-People Health Foundation, Inc.

  6. Volume of Plasma Expansion and Functional Outcomes in Stroke.

    Science.gov (United States)

    Miller, Joseph B; Lewandowski, Christopher; Wira, Charles R; Taylor, Andrew; Burmeister, Charlotte; Welch, Robert

    2017-04-01

    Plasma expansion in acute ischemic stroke has potential to improve cerebral perfusion, but the long-term effects on functional outcome are mixed in prior trials. The goal of this study was to evaluate how the magnitude of plasma expansion affects neurological recovery in acute stroke. This was a secondary analysis of data from the Albumin in Acute Stroke Part 2 trial investigating the relationship between the magnitude of overall intravenous volume infusion (crystalloid and colloid) to clinical outcome. The data were inclusive of 841 patients with a mean age of 64 years and a median National Institutes of Health Stroke Scale (NIHSS) of 11. In a multivariable-adjusted logistic regression model, this analysis tested the volume of plasma expansion over the first 48 h of hospitalization as a predictor of favorable outcome, defined as either a modified Rankin Scale score of 0 or 1 or a NIHSS score of 0 or 1 at 90 days. This model included all study patients, irrespective of albumin or isotonic saline treatment. Patients that received higher volumes of plasma expansion more frequently had large vessel ischemic stroke and higher NIHSS scores. The multivariable-adjusted model revealed that there was decreased odds of a favorable outcome for every 250 ml additional volume plasma expansion over the first 48 h (OR 0.91, 95 % CI, 0.88-0.94). The present study demonstrates an association between greater volume of plasma expansion and worse neurological recovery.

  7. Strong anisotropic thermal expansion in cristobalite-type BPO 4

    Science.gov (United States)

    Achary, S. N.; Tyagi, A. K.

    2004-11-01

    In this communication, the thermal expansion behavior of cristobalite-type BPO 4, determined from high-temperature X-ray diffraction studies, is being reported. BPO 4 crystallizes in tetragonal lattice, with space group I-4 (No. 82) at room temperature, with unit cell parameters: a=4.3447(2), c=6.6415(5) Å and V=125.37(1) Å 3. The tetragonal unit cell parameters at 900 °C are: a=4.3939(2), c=6.6539(6) Å and V=128.46(1) Å 3. The results show a very strong anisotropic expansion in the lattice, with the typical thermal expansion coefficients along a- and c-axis 12.9×10 -6 and 2.1×10 -6/°C, respectively. The volume thermal expansion coefficient of the lattice is 28.2×10 -6/°C in the temperature range of 25-900 °C. The variation of the crystal structure with temperature and the thermal expansion behavior are explained in this manuscript. The role of inter-polyhedral angle on the thermal expansion behavior has also been established.

  8. Fracturas intertrocantéricas inestables tratadas con clavos endomedulares cortos. Intertrocantéricos/Subtrocantéricos. Valoración de la calidad de vida y de la recuperación funcional. [Unstable intertrochanteric fractures treated with ITST short intramedullary nails. Quality of life assessment and functional recovery.

    Directory of Open Access Journals (Sweden)

    Federico José Burgo

    2015-04-01

    Full Text Available Introducción El objetivo del presente estudio consistió en evaluar una serie de pacientes con fracturas intertrocantéricas inestables tratados con clavos cortos Intertrocantéricos/Subtrocantéricos ITST(NR con especial atención en la calidad de vida y la recuperación funcional. Material y métodos Se incluyeron 171 pacientes con fracturas AO 3.1 A2 y A3, con un seguimiento mínimo de 14 meses, y una edad promedio de 79 años. Se evaluó: calidad de vida, utilizando la escala de WOMAC reducida convertida a una escala del 1 al 100, recuperación funcional en función del tiempo en que se logró la bipedestación, necesidad de ortesis al final del seguimiento, y el regreso a las tareas de la vida diaria utilizando la sub-escala de función de la Sociedad Americana de Tumores Musculoesqueléticos. Resultados A los 14 meses el promedio de WOMAC total fue 77. El 73 % de la población caminó dentro de las 36 hs de la cirugía. El 48% retornó a las actividades diarias con una restricción mínima, el resto tuvo restricciones recreacionales y parciales. El 71% del grupo que no utilizaba ortesis conservó tal condición al finalizar el seguimiento. La incidencia de complicaciones intraoperatorias y postoperatoria fue 6,5% y 23%. La fractura distal al clavo y el “cut-out” se produjeron solo en el 1%. Discusión La baja incidencia de “cut-out” y fractura distal al clavo con la posibilidad de inserción temprana a las actividades, conservando una buena calidad de vida y función, convierten al ITST en un alternativa de elección para el tratamiento de las fracturas intertrocantéricas inestables de cadera.

  9. Experiencia educativa con Grupos de Facebook

    OpenAIRE

    Gómez, María Florencia

    2016-01-01

    Para continuar con el tema de este mes sobre relatos de experiencias educativas innovadoras con tecnologías, en esta publicación presentaré algunos beneficios de trabajar con Grupos Facebook para el seguimiento de un trabajo práctico grupal en la asignatura de grado Seminario de Psicología Experimental (Fac. de Psicología, UNLP). Dicha actividad consiste en el armado progresivo de una propuesta de investigación conforme se introducen las temáticas metodológicas en cada una de las clases. Asim...

  10. Miasis en paciente con Carcinoma Basocelular

    OpenAIRE

    Dr. Hugo Pérez Vedia; Claudia Mariela Cruz Copa; Daphne Ingrid Pérez López

    2012-01-01

    Paciente de sexo masculino, de 71 años de edad, proveniente de la provincia Chapare, Cochabamba, es remitido por sus familiares al servicio de Infectologíadel Hospital Obrero Nº2 Caja Nacional de Salud, tras presentar cuadro clínico de varios días de evolución, caracterizado por lesión ulcerada de bordes irregulares, con secreciónserosanguinolenta localizada en hemicara derecha, con extensión a tejidos profundos y destrucción ósea con pérdida del pabellón auricular derecho,destrucción de la f...

  11. Entornos adaptados para personas con discapacidad mental

    OpenAIRE

    Guasch Murillo, Daniel; Bonasa Jiménez, Mª del Pilar; López Novella, Judit; Mayor Sánchez, Carolina; Guasch Murillo, Yolanda

    2013-01-01

    Las universidades tienen ante sí un reto importante en conseguir entornos accesibles para el alumnado con discapacidad mental donde puedan desarrollar con éxito sus estudios universitarios y, de esta forma, mejorar sus perspectivas laborales. Sólo el 5,4% de las personas con discapacidad de 25 o más años tienen estudios universitarios o equivalentes, siendo este porcentaje del 18,7% en el caso de las personas sin discapacidad (Observatorio Estatal de la Discapacidad, 2010). Si se observa el p...

  12. Tratamiento conservador en pacientes con retinoblastoma bilateral

    Directory of Open Access Journals (Sweden)

    Juan C. Suárez

    2008-11-01

    Full Text Available OBJETIVO: comparar el tratamiento convencional del retinoblastoma bilateral, usado hasta hace algunos años, consistente en radioterapia o enucleación bilateral, con el tratamiento conservador actual que incluye termoterapia transpupilar (TTT o TTT/quimioterapia al menos en un ojo, en niños con diagnóstico de retinoblastoma bilateral. DISEÑO: estudio retrospectivo descriptivo. MUESTRA: 20 pacientes con diagnóstico de retinoblastoma bilateral que consultaron al Hospital Universitario San Vicente de Paúl, de Medellín, Colombia, entre 1997 y 2007. MÉTODO: se hizo enucleación del ojo con el tumor de mayor tamaño. En el otro ojo se hizo tratamiento con TTT, con el láser diodo (810 nm, spot amplio, solo o combinado con otras terapias. RESULTADOS: se dividió a los pacientes en dos grupos: 16 pacientes (32 ojos en el grupo 1 tratados conservadoramente y 4 pacientes (8 ojos en el grupo 2 con tratamiento convencional. El rango de edad fue de 1-72 meses en el grupo 1 y de 1-12 meses en el grupo 2. El tiempo de seguimiento fue de 7-67 meses para el grupo 1 y de 13-73 meses para el grupo 2. En el grupo 1 se hizo enucleación de 16 ojos (50%, radioterapia externa de uno (3,1%, quimioterapia más termoterapia de 5 (15,6% y quimioterapia más termoterapia más crioterapia de 10 (31,3%. En todos los pacientes se logró preservar al menos un ojo. En el grupo 2, se enuclearon 7 ojos (87,5% y se hizo radioterapia externa más enucleación en un paciente (12.5%. Además, todos los pacientes recibieron quimioterapia. CONCLUSIÓN: la terapia conservadora actual consistente en tratamiento local (termoterapia, crioterapia o braquiterapia y quimiorreducción permite preservar al menos un ojo y en algunos casos de los dos, muchas veces con buena agudeza visual, en niños con retinoblastoma bilateral; se evitan así la enucleación bilateral y la radioterapia externa usada en el tratamiento convencional con todos sus efectos secundarios. La enucleación contin

  13. con indicadores de pH caseros

    Directory of Open Access Journals (Sweden)

    Santiago Heredia-Avalos

    2006-01-01

    Full Text Available En este trabajo se describen varias experiencias sencillas relacionadas con las reacciones ácido-base. Todas ellas pueden realizarse con utensilios de cocina y usando sustancias baratas que pueden encontrarse fácilmente en un supermercado, una farmacia o en casa. En concreto, se describe la forma de obtener algunos indicadores de pH a partir de extractos vegetales o de medicamentos. Además, se proponen varias experiencias en las que se hace uso de estos indicadores con el fin de estudiar las reacciones ácido-base. Todas estas experiencias están enfocadas a alumnos de enseñanza secundaria.

  14. "En-red-ando" con la docencia

    OpenAIRE

    Gómez Ciriano, Emilio J.; Sánchez Pérez, María del Carmen

    2006-01-01

    No es una novedad en la E.U. de Trabajo Social de Cuenca desarrollar una docencia orientada al empleo y, por tanto, con una consideración importante a la formación reglada de carácter práctico. De ahí que la docencia en grupos, basada en el trabajo de los alumnos dentro y fuera de las aulas, programada, con supervisores externos, realizada sobre proyectos de intervención explícitos, con un seguimiento y evaluación continua, etc. venga siendo un rasgo característico del programa formativo de n...

  15. Pénfigo seborreico con eritema polimorfo

    OpenAIRE

    Marisabel R. Coronel Q.; Celia Chávez A; Zuan P Copana-Olmos

    2009-01-01

    Paciente femenino de 50 años, internadapor presentar dolor intenso generalizadoen la piel. Presenta lesiones dérmicasde mas o menos 2 meses de evolución, conáreas eritematosas y vesículas que confluyena ampollas con fondo eritematoso, que conel tiempo se extendió a una gran superficiedel cuerpo. Al examen físico se evidencian:lesiones dérmicas sobreinfectadas con secreciónpurulenta en algunas regiones delcuerpo (cuello y brazos) además de lesioneshiperqueratósicas y decamativas que compromete...

  16. Transverse Expansion and Stability after Segmental Le Fort I Osteotomy versus Surgically Assisted Rapid Maxillary Expansion: a Systematic Review

    Directory of Open Access Journals (Sweden)

    Thomas Starch-Jensen

    2017-01-01

    Full Text Available Objectives: The objective of the present systematic review was to test the hypothesis of no difference in transverse skeletal and dental arch expansion and relapse after segmental Le Fort I osteotomy versus surgically assisted rapid maxillary expansion. Material and Methods: A MEDLINE (PubMed, Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted by including human studies published in English from January 1, 2000 to June 1, 2016. Results: The search provided 130 titles and four studies fulfilled the inclusion criteria. All the included studies were characterized by high risk of bias and meta-analysis was not possible due to considerable variation. Both treatment modalities significantly increase the transverse maxillary skeletal and dental arch width. The transverse dental arch expansion and relapse seems to be substantial higher with tooth-borne surgically assisted rapid maxillary expansion compared to segmental Le Fort I osteotomy. The ratio of dental to skeletal relapse was significantly higher in the posterior maxilla with tooth-borne surgically assisted rapid maxillary expansion. Moreover, a parallel opening without segment tilting was observed after segmental Le Fort I osteotomy. Conclusions: Maxillary transverse deficiency in adults can be treated successfully with both treatment modalities, although surgically assisted rapid maxillary expansion seems more effective when large transverse maxillary skeletal and dental arch expansion is required. However, considering the methodological limitations of the included studies, long-term randomized studies assessing transverse skeletal and dental expansion and relapse with the two treatment modalities are needed before definite conclusions can be provided.

  17. Early Impacts of the Affordable Care Act on Health Insurance Coverage in Medicaid Expansion and Non-Expansion States.

    Science.gov (United States)

    Courtemanche, Charles; Marton, James; Ukert, Benjamin; Yelowitz, Aaron; Zapata, Daniela

    2017-01-01

    The Affordable Care Act (ACA) aimed to achieve nearly universal health insurance coverage in the United States through a combination of insurance market reforms, mandates, subsidies, health insurance exchanges, and Medicaid expansions, most of which took effect in 2014. This paper estimates the causal effects of the ACA on health insurance coverage in 2014 using data from the American Community Survey. We utilize difference-in-difference-in-differences models that exploit cross-sectional variation in the intensity of treatment arising from state participation in the Medicaid expansion and local area pre-ACA uninsured rates. This strategy allows us to identify the effects of the ACA in both Medicaid expansion and non-expansion states. Our preferred specification suggests that, at the average pre-treatment uninsured rate, the full ACA increased the proportion of residents with insurance by 5.9 percentage points compared to 2.8 percentage points in states that did not expand Medicaid. Private insurance expansions from the ACA were due to increases in both employer-provided and non-group coverage. The coverage gains from the full ACA were largest for those without a college degree, non-whites, young adults, unmarried individuals, and those without children in the home. We find no evidence that the Medicaid expansion crowded out private coverage.

  18. Breaking the link between environmental degradation and oil palm expansion: a method for enabling sustainable oil palm expansion.

    Directory of Open Access Journals (Sweden)

    Hans Harmen Smit

    Full Text Available Land degradation is a global concern. In tropical areas it primarily concerns the conversion of forest into non-forest lands and the associated losses of environmental services. Defining such degradation is not straightforward hampering effective reduction in degradation and use of already degraded lands for more productive purposes. To facilitate the processes of avoided degradation and land rehabilitation, we have developed a methodology in which we have used international environmental and social sustainability standards to determine the suitability of lands for sustainable agricultural expansion. The method was developed and tested in one of the frontiers of agricultural expansion, West Kalimantan province in Indonesia. The focus was on oil palm expansion, which is considered as a major driver for deforestation in tropical regions globally. The results suggest that substantial changes in current land-use planning are necessary for most new plantations to comply with international sustainability standards. Through visualizing options for sustainable expansion with our methodology, we demonstrate that the link between oil palm expansion and degradation can be broken. Application of the methodology with criteria and thresholds similar to ours could help the Indonesian government and the industry to achieve its pro-growth, pro-job, pro-poor and pro-environment development goals. For sustainable agricultural production, context specific guidance has to be developed in areas suitable for expansion. Our methodology can serve as a template for designing such commodity and country specific tools and deliver such guidance.

  19. Breaking the link between environmental degradation and oil palm expansion: a method for enabling sustainable oil palm expansion.

    Science.gov (United States)

    Harmen Smit, Hans; Meijaard, Erik; van der Laan, Carina; Mantel, Stephan; Budiman, Arif; Verweij, Pita

    2013-01-01

    Land degradation is a global concern. In tropical areas it primarily concerns the conversion of forest into non-forest lands and the associated losses of environmental services. Defining such degradation is not straightforward hampering effective reduction in degradation and use of already degraded lands for more productive purposes. To facilitate the processes of avoided degradation and land rehabilitation, we have developed a methodology in which we have used international environmental and social sustainability standards to determine the suitability of lands for sustainable agricultural expansion. The method was developed and tested in one of the frontiers of agricultural expansion, West Kalimantan province in Indonesia. The focus was on oil palm expansion, which is considered as a major driver for deforestation in tropical regions globally. The results suggest that substantial changes in current land-use planning are necessary for most new plantations to comply with international sustainability standards. Through visualizing options for sustainable expansion with our methodology, we demonstrate that the link between oil palm expansion and degradation can be broken. Application of the methodology with criteria and thresholds similar to ours could help the Indonesian government and the industry to achieve its pro-growth, pro-job, pro-poor and pro-environment development goals. For sustainable agricultural production, context specific guidance has to be developed in areas suitable for expansion. Our methodology can serve as a template for designing such commodity and country specific tools and deliver such guidance.

  20. In vitro evaluation of force-expansion characteristics in a newly designed orthodontic expansion screw compared to conventional screws

    Directory of Open Access Journals (Sweden)

    Oshagh Morteza

    2009-01-01

    Full Text Available Objective : Expansion screws like Hyrax, Haas and other types, produce heavy interrupted forces which are unfavorable for dental movement and could be harmful to the tooth and periodontium. The other disadvantage of these screws is the need for patient cooperation for their regular activation. The purpose of this study was to design a screw and compare its force- expansion curve with other types. Materials and Methods : A new screw was designed and fabricated in the same dimension, with conventional types, with the ability of 8 mm expansion (Free wire length: 12 mm, initial compression: 4.5 mm, spring wire diameter: 0.4 mm, spring diameter: 3 mm, number of the coils: n0 ine, material: s0 tainless steel. In this in vitro study, the new screw was placed in an acrylic orthodontic appliance, and after mounting on a stone cast, the force-expansion curve was evaluated by a compression test machine and compared to other screws. Results : Force-expansion curve of designed screw had a flatter inclination compared to other screws. Generally it produced a light continuous force (two to 3.5 pounds for every 4 mm of expansion. Conclusion : In comparison with heavy and interrupted forces of other screws, the newly designed screw created light and continuous forces.

  1. Desensibilización con aspirina en un paciente con intolerancia a antiinflamatorios no esteroides

    Directory of Open Access Journals (Sweden)

    Mirta Álvarez Castelló

    2011-12-01

    Full Text Available El ácido acetilsalicílico o aspirina es uno de los medicamentos más utilizados a nivel mundial. Los pacientes con enfermedad coronaria requieren tratamientos prolongados con este medicamento, el cual se les niega a aquellos con historias de reacciones adversas a este. Se recoge en la literatura internacional el uso de terapias de desensibilización en pacientes con intolerancia a los antiinflamatorios no esteroides con diferentes protocolos, con resultados satisfactorios. En este trabajo se describe la primera desensibilización con aspirina realizada a un paciente en el Hospital Universitario «Calixto García» y el protocolo de actuación utilizado. No se encontró otro caso en la bibliografía nacional. El paciente actualmente ingiere 125 mg diarios sin reacciones adversas. Se considera que la desensibilización con aspirina es una opción terapéutica efectiva en aquellos pacientes con intolerancia a esta y con una afección que justifique este proceder.

  2. Experiencias y aprendizajes con juegos cooperativos

    National Research Council Canada - National Science Library

    Evelyn Cerdas Agüero

    2013-01-01

    El presente trabajo tiene como objetivo presentar experiencias y aprendizajes que  han logrado algunos grupos de docentes con los que se ha trabajado por medio de talleres de juegos cooperativos para la paz...

  3. Complicaciones asociadas con osteotomia Le Fort I

    National Research Council Canada - National Science Library

    Duque S., Francisco L; Jaramillo V., Pedro M

    2009-01-01

    .... La osteotomia Le Fort I esta relacionada con gran variedad de complicaciones. Un conocimiento preciso de las complicaciones deberia ayudar al cirujano, al ortodoncista y al paciente para estimar los beneficios de una cirugia electiva versus los riesgos...

  4. Presa con revestimiento asfáltico

    Directory of Open Access Journals (Sweden)

    Proudfit, D. P.

    1960-07-01

    Full Text Available La presa denominada Montgomery se halla situada sobre el río South Platte River, a unos 8 km aguas arriba de la ciudad de Alma, del Estado de Colorado (EE. UU., y en la ladera oriental de la cordillera Continental Divide. El cuerpo o dique de esta presa está constituido por piedra, revestida con una capa de hormigón asfáltico en el paramento de contacto con el agua.

  5. Trastornos temporomandibulares en pacientes con maloclusiones

    Directory of Open Access Journals (Sweden)

    Luis Soto Cantero

    Full Text Available Introducción: existe una prevalencia de trastornos oclusales en gran medida relacionados con la presencia de disfunción temporomandibular. Objetivo: determinar el grado de disfunción temporomandibular según el Índice de Maglione en correspondencia con la prevalencia de maloclusiones en el área de salud del policlínico "Turcios Lima". Métodos: se realizó un estudio observacional descriptivo, de corte transversal, en la consulta de ortodoncia, de junio del 2008 a junio del 2009. De un universo constituido por los 280 pacientes que acudieron al servicio de ortodoncia en el período señalado con presencia de maloclusiones, se seleccionó una muestra de 84 pacientes por muestreo aleatorio simple, teniendo en cuenta los criterios de inclusión y exclusión realizados por criterios de expertos. Resultados: presentaban disfunción temporomandibular 74 pacientes y dentro de ellos 44 (52,4 % tenían disfunción grado II (Moderada. El 97 % de los pacientes con relación molar de clase II, presentaban disfunción temporomandibular. El 42,9 % de los pacientes con una maloclusión, presentaban disfunción grado I. El 60 % de los pacientes con dos maloclusiones presentaban disfunción grado II y el 66,7 % de los pacientes con tres maloclusiones, presentaban disfunción grado III. La mayor cantidad de pacientes tuvieron disfunción grado II (Moderada. Conclusiones: el mayor por ciento de los pacientes con disfunciones presentó una clase II molar y a medida que aumentó el número de maloclusiones aumentó también la severidad de la disfunción.

  6. Adolescente femenino con granulomatosis de Wegener fulminante

    Directory of Open Access Journals (Sweden)

    S C Scheffler-Mendoza

    2017-01-01

    Full Text Available Adolescente femenino de 13 años de edad, originaria de Guerrero, grupo étnico mixteco, padres analfabetos y con poco entendimiento del español. Sin otros antecedentes de importancia para el padecimiento. Inició un mes previo con la aparición de una pápula hipercrómica en párpado superior derecho que en los 10 días previos al ingreso aumentó de volumen generando proptosis. Al interrogatorio se negó dolor, lagrimeo, fiebre, o pérdida de peso. Ingresó con fiebre (39.0°C, palidez generalizada, proptosis derecha con exposición de córnea y conjuntiva, eritema periorbitario, movimientos oculares y agudeza visual disminuidos (i.e. contaba dedos a 1 m, pupila con tendencia a midriasis, hiperreactividad a la luz, y fondo de ojo con papila hiperémica edematosa y tortuosidad peripapilar. El resto de exploración no mostró datos relevantes. Se hospitalizó para iniciar tratamiento antimicrobiano parenteral de amplio espectro (i.e. ceftriaxona y vancomicina y abordar proptosis unilateral.

  7. Aspectos evolutivos de las personas con discapacidad, 2007-08

    OpenAIRE

    Santiago Vicente Martín, Santiago

    2007-01-01

    I. Materiales de clase: Tema 1: INTRODUCCIÓN AL CONCEPTO DE NECESIDADES EDUCATIVAS ESPECIALES; Tema 2: ASPECTOS EVOLUTIVOS DE LAS PERSONAS CON DISCAPACIDAD VISUAL; Tema 3: ASPECTOS EVOLUTIVOS DE LAS PERSONAS CON RETRASO MENTAL; Tema 4: ASPECTOS EVOLUTIVOS DE LAS PERSONAS CON DISCAPACIDAD MOTORA; Tema 5: ASPECTOS EVOLUTIVOS DE LAS PERSONAS CON AUTISMO; Tema 6: ALUMNOS CON ALTAS CAPACIDADES. II. Bibliografía Aspectos evolutivos de las personas con discapacidad: Los objetivos de la asignatura...

  8. The acoustics of short circular holes with finite expansion ratio

    Science.gov (United States)

    Yang, Dong; Morgans, Aimee

    2016-11-01

    The acoustic response of a circular hole with mean flow passing through it is highly relevant to Helmholtz resonators, fuel injectors, perforated liners, perforated plates and many other engineering applications. Analytical models for the acoustic response of these holes often ignore the impact of a finite expansion ratio either side, or account for it simply by adding an end mass inertial correction derived from the no mean flow assumption. The vortex-sound interaction within a short hole has been recently shown to strongly affect the acoustic response in the low frequency region. The present study uses an analytical model based on the Green's function method to investigate how the expansion ratios either side of a short hole affect the vortex-sound interaction within it - something neglected by previous models. This model is then incorporated into a Helmholtz resonator model, allowing us to consider the effect of a finite neck-to-cavity expansion ratio and the vortex-sound interaction within the finite length neck. Large resistance and acoustic energy absorption performance variations are seen even for small changes in the resonator neck length. Reducing the neck-to-cavity expansion ratio is found to decrease the resonator's sound absorption when the expansion ratio is low. CSC-Imperial PhD Scholarship; ERC Starting Grant, ACOULOMODE (2013-18).

  9. Underwater expansion wave focusing by reflecting at the air interface

    Science.gov (United States)

    Ohtani, K.; Ogawa, T.

    2017-02-01

    This paper reports a preliminarily experimental result of high-speed shadowgraph optical visualization of underwater expansion wave focusing by using a simple two-dimensional wedge model for understanding of shock wave interaction phenomena in simulated biomedical materials. Underwater shock wave generated by detonating a micro-explosive (10 mg silver azide pellet) in a small chamber. The generated underwater shock wave was interacted with a wedge shaped interface between water and air divided by a thin film, and an expansion wave was generated by reflection at the interface. The process of underwater expansion wave generation and focusing phenomena was visualized by shadowgraph method and recorded by ultra-high-speed framing camera. Underwater shock wave was reflected as an expansion wave from the interface between water and air at the both side and focused and then cavitation bubble was created by pressure decreasing at the expansion wave focusing area. The pressure histories were measured simultaneously with high-speed optical visualization by a needle type pressure sensor. At the focusing area, the pressure was decreased rapidly, the negative peak pressure was the lowest.

  10. Infinite S-expansion with ideal subtraction and some applications

    Science.gov (United States)

    Peñafiel, D. M.; Ravera, L.

    2017-08-01

    According to the literature, the S-expansion procedure involving a finite semigroup is valid no matter what the structure of the original Lie (super)algebra is; however, when something about the structure of the starting (super)algebra is known and when certain particular conditions are met, the S-expansion method (with its features of resonance and reduction) is able not only to lead to several kinds of expanded (super)algebras but also to reproduce the effects of the standard as well as the generalized Inönü-Wigner contraction. In the present paper, we propose a new prescription for S-expansion, involving an infinite abelian semigroup S(∞ ) and the subtraction of an infinite ideal subalgebra. We show that the subtraction of the infinite ideal subalgebra corresponds to a reduction. Our approach is a generalization of the finite S-expansion procedure presented in the literature, and it offers an alternative view of the generalized Inönü-Wigner contraction. We then show how to write the invariant tensors of the target (super)algebras in terms of those of the starting ones in the infinite S-expansion context presented in this work. We also give some interesting examples of application on algebras and superalgebras.

  11. Some properties of Riesz means and spectral expansions

    Directory of Open Access Journals (Sweden)

    S. A. Fulling

    1999-03-01

    Full Text Available It is well known that short-time expansions of heat kernels correlate to formal high-frequency expansions of spectral densities. It is also well known that the latter expansions are generally not literally true beyond the first term. However, the terms in the heat-kernel expansion correspond rigorously to quantities called Riesz means of the spectral expansion, which damp out oscillations in the spectral density at high frequencies by dint of performing an average over the density at all lower frequencies. In general, a change of variables leads to new Riesz means that contain different information from the old ones. In particular, for the standard second-order elliptic operators, Riesz means with respect to the square root of the spectral parameter correspond to terms in the asymptotics of elliptic and hyperbolic Green functions associated with the operator, and these quantities contain ``nonlocal'' information not contained in the usual Riesz means and their correlates in the heat kernel. Here the relationship between these two sets of Riesz means is worked out in detail; this involves just classical one-dimensional analysis and calculation, with no substantive input from spectral theory or quantum field theory. This work provides a general framework for calculations that are often carried out piecemeal (and without precise understanding of their rigorous meaning in the physics literature.

  12. k-string tensions and the 1/N expansion

    CERN Document Server

    Greensite, Jeff; Patella, Agostino

    2011-01-01

    We address the question of whether the large-N expansion in pure SU(N) gauge theories requires that k-string tensions must have a power series expansion in 1/N^2, as in the sine law, or whether 1/N contributions are also allowable, as in Casimir scaling. We find that k-string tensions may, in fact, have 1/N corrections, and consistency with the large-N expansion in the open-string sector depends crucially on an exact cancellation, which we will prove, among terms involving odd powers of 1/N in particular combinations of Wilson loops. It is shown how these cancellations are fulfilled, and consistency with the large-N expansion achieved, in a concrete example, namely, strong-coupling lattice gauge theory with the heat-kernel action. This is a model which has both a 1/N^2 expansion and Casimir scaling of the k-string tensions. Analysis of the closed string channel in this model confirms our conclusions, and provides further insights into the large-N dependence of energy eigenstates and eigenvalues.

  13. Urban Land Expansion and Spatial Dynamics in Globalizing Shanghai

    Directory of Open Access Journals (Sweden)

    Han Li

    2014-12-01

    Full Text Available Urban land expansion in China has attracted considerable scholarly attention. However, more work is needed to apply spatial modeling to understanding the mechanisms of urban growth from both institutional and physical perspectives. This paper analyzes urban expansion in Shanghai and its development zones (DZs. We find that, as nodes of global-local interface, the DZs are the most significant components of urban growth in Shanghai, and major spatial patterns of urban expansion in Shanghai are infilling and edge expansion. We apply logistic regression, geographically weighted logistic regression (GWLR and spatial regime regression to investigate the determinants of urban land expansion including physical conditions, state policy and land development. Regressions reveal that, though the market has been an important driving force in urban growth, the state has played a predominant role through the implementation of urban planning and the establishment of DZs to fully capitalize on globalization. We also find that differences in urban growth dynamics exist between the areas inside and outside of the DZs. Finally, this paper discusses policies to promote sustainable development in Shanghai.

  14. EXPANSION OF SOLIDARY ECONOMY IN THE SOUTH OF BRAZIL

    Directory of Open Access Journals (Sweden)

    Bolívar Alencar Ribeiro

    2013-03-01

    Full Text Available This work was based in a detailed analysis of supplied informations by SIES/MTE, the major database about Solidary Economy in Brazil. The object of this study was the expansion of the solidary economy in the south region of Brazil. This way the general objective to understand and to analyze the expansion of the solidary economy in the south region of Brazil. Thereby search to demonstrate the considerable expansion of activities under the principles of Economics Solidary, this occured on the crisis of formal employment in the decade of 1990, and your apex of growth after the year 2000, when this began to configure how public policy at national. This expansion it was given of differentiated form in Rio Grande do Sul state in general and in pioneering municipalities in the actions that involved the Solidary Economy. Had been considered as hypotheses for this expansion the actions of support entities and the implantation of public politics of support the solidary economy. The research it showed that existence of entities of support, governmental actions,organization capacity of the involved ones beyond the accumulation of experiences is that propitiates matureness of the joint around the solidary economy and induces the creation of public politics of support.

  15. An analytical model for the assessment of airline expansion strategies

    Directory of Open Access Journals (Sweden)

    Mauricio Emboaba Moreira

    2014-01-01

    Full Text Available Purpose: The purpose of this article is to develop an analytical model to assess airline expansion strategies by combining generic business strategy models with airline business models. Methodology and approach: A number of airline business models are examined, as are Porter’s (1983 industry five forces that drive competition, complemented by Nalebuff/ Brandenburger’s  (1996 sixth force, and the basic elements of the general environment in which the expansion process takes place.  A system of points and weights is developed to create a score among the 904,736 possible combinations considered. The model’s outputs are generic expansion strategies with quantitative assessments for each specific combination of elements inputted. Originality and value: The analytical model developed is original because it combines for the first time and explicitly elements of the general environment, industry environment, airline business models and the generic expansion strategy types. Besides it creates a system of scores that may be used to drive the decision process toward the choice of a specific strategic expansion path. Research implications: The analytical model may be adapted to other industries apart from the airline industry by substituting the element “airline business model” by other industries corresponding elements related to the different specific business models.

  16. Advanced methodology for generation expansion planning including interconnected systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, M.; Yokoyama, R.; Yasuda, K. [Tokyo Metropolitan Univ. (Japan); Sasaki, H. [Hiroshima Univ. (Japan); Ogimoto, K. [Electric Power Development Co. Ltd., Tokyo (Japan)

    1994-12-31

    This paper reviews advanced methodology for generation expansion planning including interconnected systems developed in Japan, putting focus on flexibility and efficiency in a practical application. First, criteria for evaluating flexibility of generation planning considering uncertainties are introduced. Secondly, the flexible generation mix problem is formulated as a multi-objective optimization with more than two objective functions. The multi-objective optimization problem is then transformed into a single objective problem by using the weighting method, to obtain the Pareto optimal solution, and solved by a dynamics programming technique. Thirdly, a new approach for electric generation expansion planning of interconnected systems is presented, based on the Benders Decomposition technique. That is, large scale generation problem constituted by the general economic load dispatch problem, and several sub problems which are composed of smaller scale isolated system generation expansion plans. Finally, the generation expansion plan solved by an artificial neural network is presented. In conclusion, the advantages and disadvantages of this method from the viewpoint of flexibility and applicability to practical generation expansion planning are presented. (author) 29 refs., 10 figs., 4 tabs.

  17. Reversión del Atracurium con dosis residuales de Neostigmine monitoreada con TOF WATCH

    OpenAIRE

    Jaramillo Mendoza, Karol Rodrigo

    2012-01-01

    Es de suma importancia conocer el momento exacto de la descurarización y las dosis más convenientes de la neostigmine y de la atropina, con la finalidad de tener resultados positivos que favorezcan al estado hemodinámico sin que haya mayores alteraciones para el paciente. Se realizó un estudio en 82 pacientes en el Hospital Enrique Sotomayor, los cuales fueron monitoreados con TOF WATCH, con la finalidad de revertir el atracurium con dosis residuales de neostigmine. El 32...

  18. Higiene postural relacionado con la integración de alumnos con necesidades educativas especiales

    OpenAIRE

    Martín Rodríguez, Cristina

    2014-01-01

    A lo largo de este trabajo pretendemos demostrar la importancia de la prevención e higiene postural para el mantenimiento de la salud de la comunidad educativa, con el objetivo de crear escuelas saludables. Hemos querido relacionar este tema con la inclusión e integración escolar de los alumnos con necesidades educativas especiales, partiendo de las inquietudes del resto del alumnado por el mobiliario adaptado y utilizado por los alumnos con discapacidad motórica. En primer ...

  19. Enfermedad coronaria en pacientes con psoriasis

    Directory of Open Access Journals (Sweden)

    Walter Masson

    2013-10-01

    Full Text Available Comunicaciones previas asociaron la psoriasis con la enfermedad coronaria. Desconocemos si en nuestro país o región existe dicha asociación. Se realizó un estudio transversal analizando los datos de la historia clínica electrónica de un sistema de salud de Buenos Aires. Analizamos todos los pacientes mayores de 18 años con diagnóstico de psoriasis entre el 1 de enero de 2003 y el 31 de julio de 2011 y los comparamos con un grupo control, en una relación 2:1, obtenido en forma aleatoria del mismo sistema de salud, apareados por edad y sexo. Determinamos la prevalencia de los factores de riesgo cardiovascular y de enfermedad coronaria. Analizamos la asociación entre la enfermedad coronaria y la psoriasis mediante análisis uni y multivariado. Se incluyeron 3 833 sujetos (1 286 pacientes con psoriasis y 2 547 controles. La prevalencia de hipertensión arterial (50% vs. 38%, p < 0.001, tabaquismo (25% vs. 17%, p < 0.001, diabetes (12% vs. 8%, p < 0.001 y enfermedad coronaria (4.98% vs. 3.06%, p = 0.003 fue mayor en los sujetos con psoriasis en comparación con el grupo control. Independientemente de la edad, la presencia de diabetes, hipertensión arterial o tabaquismo, hubo una asociación significativa entre la enfermedad coronaria y la psoriasis (OR 1.48, IC95% 1.04-2.11, p = 0.03. En conclusión, en esta población de Buenos Aires, los pacientes con psoriasis tuvieron una mayor prevalencia de diabetes, hipertensión arterial, tabaquismo y enfermedad coronaria. La asociación entre la psoriasis y la enfermedad coronaria fue independiente de los factores de riesgo explorados.

  20. Expansion/Facemask Treatment of an Adult Class III Malocclusion

    Directory of Open Access Journals (Sweden)

    Gregory W. Jackson

    2014-01-01

    Full Text Available The orthodontic treatment of class III malocclusion with a maxillary deficiency is often treated with maxillary protraction with or without expansion. Skeletal and dental changes have been documented which have combined for the protraction of the maxilla and the correction of the class III malocclusion. Concerning the ideal time to treat a developing class III malocclusion, studies have reported that, although early treatment may be the most effective, face mask therapy can provide a viable option for older children as well. But what about young adults? Can the skeletal and dental changes seen in expansion/facemask therapy in children and adolescents be demonstrated in this age group as well, possibly eliminating the need for orthodontic dental camouflage treatment or orthognathic surgery? A case report is presented of an adult class III malocclusion with a Class III skeletal pattern and maxillary retrusion. Treatment was with nonextraction, comprehensive edgewise mechanics with slow maxillary expansion with a bonded expander and protraction facemask.