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Sample records for analisis pinch para

  1. Application of the Pinch analysis for the design of a cogeneration system in a paper mill; Aplicacion del analisis Pinch para el diseno de un sistema de cogeneracion en una industria papelera

    Energy Technology Data Exchange (ETDEWEB)

    Mani Gonzalez, A. G.; Arriola Medellin, A. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    The Pinch Analysis is a set of principles, tools and rules for the design that allow the engineer find the best way to configure the elements of a process. In the last ten years it has been utilized for the design of new processes as well as in the energy optimization of existing processes. In this paper the tools utilized for the integration of a cogeneration system in a process for the production of paper is presented. It is also presented how the combined treatment of the Pinch Analysis and the exergy concept allows to define, before the detailed design, the cogeneration potential, the fuel consumption and the amount of pollutant emissions for different cogeneration schemes. [Espanol] El analisis Pinch es un conjunto de principios, herramientas y reglas de diseno que permiten al ingeniero encontrar la mejor manera de configurar los elementos de un proceso. En los ultimos diez anos se ha utilizado para el diseno de procesos nuevos asi como en la optimacion energetica de procesos existentes. En el presente articulo se presentan las herramientas utilizadas para la integracion de un sistema de cogeneracion en un proceso de produccion de papel. Se muestra tambien como el tratamiento combinado del analisis Pinch y el concepto de energia permite definir, antes del diseno detallado, el potencial de cogeneracion, el consumo de combustible y la cantidad de emisiones contaminantes para diferentes esquemas de cogeneracion.

  2. Expert system for failure analysis of shafts; Sistema experto para analisis de falla de ejes

    Energy Technology Data Exchange (ETDEWEB)

    Jacobo Armendariz, V.H.; Cerrud Sanchez, S.M.; Ramirez Rodriguez, M.A.; Ortiz Prado, A. [Facultad de Ingenieria, UNAM, Mexico, D.F. (Mexico)

    2002-09-01

    An expert system for the failure analysis in metallic mechanical devices is being Developer at the Mechanical Engineering departments of the Faculty of Engineering of the Universidad Nacional Autonoma de Mexico (UNAM) to provide a solution for the failure analysis in cases where considerable experience in needed. The system pretends to resolve the scarceness of experts in the field of failure analysis and is oriented toward the metal-mechanics industry and will also have didactic applications. The main complication in the development of the system is the broad range of applications envisioned, like gears, shafts, bolts and springs between others. Therefore, it was decided to develop the system in a modular way, using the experience obtained in a first module to proceed faster in the others. The present paper presents the elaboration of the module that analyses shafts. This will serve as the base to expand the system toward other components. It uses the general structure of the global system, including an auxiliary software for the determination of maximum stresses in the corresponding parts. [Spanish] Con el fin de contar con un medio eficaz para la solucion de problemas relacionados con el analisis de falla, en donde la experiencia juega un papel fundamental, el Departamento de Ingenieria Mecanica de la Facultad de ingenieria de la Universidad Nacional Autonoma de Mexico (UNAM) , esta desarrollando el proyecto Sistema experto para analisis de falla de elementos mecanicos, dicho sistema busca resolver el inconveniente de la escasez de expertos y se orienta, tanto a la necesidad de la industria metalmecanica como a la de la docencia. Presenta tambien complicaciones en su desarrollo, ya que se pretende la posibilidad de realizar analisis de falla de elementos como ejes, engranes, pernos, bielas, resortes, tornillos etc. Por lo anterior, se establecio como estrategia el desarrollo del sistema por modulos, ya que teniendo la experiencia de elaboracion de un primer

  3. Practical aspects of the application of the pinch technology for the reduction of the energy and cooling water consumption in a fertilizer plant; Aspectos practicos de la aplicacion de la tecnologia pinch para la reduccion del consumo de energia y agua de enfriamiento de una planta de fertilizantes

    Energy Technology Data Exchange (ETDEWEB)

    Picon Nunez, M. [Guanajuato (Mexico)

    1995-12-31

    The energy and cooling water system make-up water consumption of a fertilizer plant were reduced in 18% and in 16.4 Tons/hr respectively, representing a substantial saving in the operational costs. The application of the pinch analysis to the process revealed the potential saving of existing energy. The need of reducing the incoming raw materials temperature and the operating pressure of two evaporators was identified, for this purpose it was necessary to install three additional heat exchangers. [Espanol] Los consumos de energia y de agua de reposicion del sistema de enfriamiento de una planta de fertilizantes se redujeron en 18% y en 16.4 ton/hr respectivamente, representando un ahorro sustancial en los costos de operacion. La aplicacion del analisis Pinch al proceso revelo el potencial de ahorro de energia existente. Se identifico la necesidad de reducir la temperatura de alimentacion de la materia prima y la presion de operacion de dos evaporadores, para lo cual fue necesario implementar tres intercambiadores de calor adicionales.

  4. Pinched Nerve

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS NINDS Pinched Nerve Information Page Table of Contents (click to jump ... being done? Clinical Trials Organizations What is Pinched Nerve? The term "pinched nerve" is a colloquial term ...

  5. Analisis de los Servicios y Aplicaciones LBS. Desarrollo de una plataforma de apoyo para la gestión de procesos y localización de personas

    OpenAIRE

    IRIMIA CERVERA, JAVIER

    2015-01-01

    Irimia Cervera, J. (2015). Analisis de los Servicios y Aplicaciones LBS. Desarrollo de una plataforma de apoyo para la gestión de procesos y localización de personas [Tesis doctoral no publicada]. Universitat Politècnica de València. doi:10.4995/Thesis/10251/48879.

  6. Analysis tools for simulation of hybrid systems; Herramientas de analisis para simulacion de sistemas hibridos

    Energy Technology Data Exchange (ETDEWEB)

    Guillen S, Omar; Mejia N, Fortino [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2005-07-01

    In order to facilitate and to simplify the development and analysis of a Hybrid System in reference to its design, construction, operation and maintenance, it turns out optimal to carry out the simulation of this one by means of software, with which a significant reduction in the investment costs is obtained. Given the mix of technology of electrical generation which is involved in a hybrid system, it is very important to have a tool integrated with specialized packages of calculation (software), that allow to carry out the simulation tasks of the operational functioning of these systems. Combined with the former, one must not fail to consider the operation characteristics, the facilities of the user, the clarity in the obtained results and the possibility of its validation with respect to prototypes orchestrated in field. Equally, it is necessary to consider the identification of tasks involved in relation to the place of installation of this electrification technology. At the moment, the hybrid systems technology still is in a stage of development in the international level, and exist important limitations as far as the methodology availability and engineering tools for the optimum design of these systems. With the development of this paper, it is intended to contribute to the advance of the technology and to count on own tools to solve the described series of problems. In this article are described the activities that more impact have in the design and development of hybrid systems, as well as the identification of variables, basic characteristics and form of validation of tools in the integration of a methodology for the simulation of these systems, facilitating their design and development. [Spanish] Para facilitar y simplificar el desarrollo y analisis de un Sistema Hibrido en lo que refiere a su diseno, construccion, operacion y mantenimiento, resulta optimo efectuar la simulacion de este por medio de un software, con lo que se obtiene una reduccien

  7. Thermal analysis of the integration of an ammonia plant; Analisis de la integracion termica de una planta de amoniaco

    Energy Technology Data Exchange (ETDEWEB)

    Arriola Medellin, Alejandro M.; Huante Perez, Liborio; Rodriguez Martinez, J. Hugo; Alcaraz Calderon, A. Moises [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: aarriola@iie.org.mx; lhp@iie.org.mx; jhrm@iie.org.mx; malcaraz@iie.org.mx

    2010-11-15

    In this paper the thermal integration of an existing ammonia plant is evaluated using the Pinch Analysis tools. It is shown the design criteria that would have to fulfill the heat recovery network to take advantage of process streams thermal potentials. It was identified the heat recovery equipment that induces energy losses by incorrect streams selection, and the economic implications. [Spanish] En este trabajo se evalua la integracion termica de una planta existente de amoniaco usando las herramientas del analisis Pinch. Se muestran los criterios de diseno que deberian de cumplir las redes de recuperacion de calor, para aprovechar al maximo el potencial termico de las corrientes del proceso. Tomando como base dichos criterios se analizo el diseno la red de recuperacion de calor de la planta existente, identificando los equipos de recuperacion de calor que generan perdidas de calor por la seleccion incorrecta de las corrientes. Se estiman las perdidas economicas derivadas del diseno ineficiente de la red.

  8. SISTEMAS DE TRATAMIENTO PARA RESIDUOS LIQUIDOS GENERADOS EN LABORATORIOS DE ANALISIS QUIMICO

    Directory of Open Access Journals (Sweden)

    BERRIO LINDA

    2012-12-01

    Full Text Available Actualmente los residuos líquidos de laboratorios de análisis químicos plantean una problemática que enfrentan distintas entidades públicas y privadas debido al manejo y la gestión integral que requieren. Este artículo revisa las diversas tecnologías de tratamientos y sus eficiencias de remoción, con el fin de establecer criterios para seleccionar el sistema y las variables adecuadas que permitan el cumplimiento de los objetivos de investigación y la sostenibilidad ambiental. La revisión inicia con una contextualización del problema y continúa con el estudio de los tratamientos para los residuos de laboratorio. Estas tecnologías se dividen en dos corrientes: tratamientos biológicos y fisicoquímicos, los cuales a su vez comprenden una gran variedad de procesos, algunos de los cuales se consideran en esta revisión.

  9. Spherical pinch

    International Nuclear Information System (INIS)

    This is essentially a review article covering several years of work on the spherical pinch (SP) concept of plasma formation and containment. Central to this concept is the creation of a hot plasma in the center of a sphere, plasma which is then compressed by strong imploding shock waves launched from the periphery of the vessel. The experimental program, which started with the classical cylindrical theta-pinch and continued with the inductive spherical pinch, has taken a turn, in recent times, with the discovery of the scaling laws governing spherical pinch experiments, which prescribe that high gas pressures are required for achieving fusion break-even conditions. As a consequence, energy deposition in present spherical pinch devices is done through resistive, rather than inductive, discharges. In a pilot experimental program of modest initial condenser bank energy (∼ 1 KJ), we find that the instantaneous energy deposition in the central plasma can lead to temperatures of the order of 2 KeV, in agreement with the prediction of the Braginskii resistivity for such a plasma, and with the relation to the velocity of the diverging shock wave generated by the sudden deposition of energy into this plasma. Moreover, when the imploding shock waves contain the central plasma, we find the containment time to be as long as 5.4 μsec and the plasma to be stable. In discharges in deuterium, neutrons are emitted close to 107 per shot. From the experimental parameters of the plasma, one can derive a particle density for the shocked gas equal to 3.21 x 1019 cm-3, a plasma temperature equal to 730 eV and a product ntau = 1.73 x 1014 cm-3 sec

  10. Analysis methodology for economic technical feasibility studies in offshore electrical generation systems; Metodologia de analisis para estudios de factibilidad tecnica economica en sistemas de generacion electrica costa fuera

    Energy Technology Data Exchange (ETDEWEB)

    Fiscal Escalante, Raul [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2007-07-01

    An analysis methodology followed in the development of technique-economic feasibility studies of systems of electrical generation in offshore electrical installations is presented, including the obtaining of the curves of the turbine and generator performance, the technical considerations for the formulation of the operation scenes and the calculations of the economic evaluation of a real scenario. [Spanish] Se muestra una metodologia de analisis seguida en el desarrollo de estudios de factibilidad tecnica-economica de sistemas de generacion electrica en instalaciones electricas costa fuera, incluyendo la obtencion de las curvas de comportamiento de la turbina y el generador, las consideraciones tecnicas para la formulacion de los escenarios de operacion y los calculos de la evaluacion economica de un escenario real.

  11. Metodologia para el analisis de demanda laboral mediante datos de Internet: el caso colombiano

    Directory of Open Access Journals (Sweden)

    Jeisson Arley Cardenas Rubio

    2015-06-01

    Full Text Available La coyuntura laboral reciente del desempleo en Colombia muestra que su componente cíclico se ha reducido a su mínima expresión y que, por ende, la mayor parte del desempleo actual hace referencia a las tipologías friccional y estructural del desempleo, y puede ser explicado en gran parte por el “mismatch” existente entre la demanda y la oferta de trabajo. La carencia de información sobre las necesidades y requerimientos del sector productivo ahondan y mantiene, aún más, las brechas existentes entre ambos componentes del mercado laboral. Dada esta situación, este trabajo propone una solución a la falta de información sobre los requerimientos cuantitativos y cualitativos de la demanda de trabajo, desde una metodología de big data, es decir, la aglomeración y sistematización de grandes cantidades de información, teniendo como fuente de información la utilizada por las bolsas de empleo colombianas en sus actividades de colocación. Procesada esta información, y luego comparada con la información de oferta laboral disponible en encuestas de hogares, puede concluirse que una base de vacantes construida a partir de big data en Colombia, es una excelente herramienta para conocer la demanda que, por distintas habilidades, tiene el sector productivo y, por ende, la formulación de políticas públicas integrales de educación y formación, sumamente requeridas en el país. Este artículo documenta el esfuerzo pionero desarrollado al respecto.

  12. Analysis of pumping systems to large flows of cooling water in power plants; Analisis de sistemas de bombeo para grandes flujos de agua de enfriamiento en centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Sanchez, Ramon; Herrera Velarde, Jose Ramon; Gonzalez Sanchez, Angel [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rsanchez@iie.org.mx; jrhv@iie.org.mx; ags@iie.org.mx

    2010-11-15

    Accurate measurement of large water flows remains being a challenge in the problems of implementation of circulating water systems of power plants and other applications. This paper, presents a methodology for the analysis in pumping systems with high rates of water in power plants, as well as their practical application and results in pipelines water flow of a thermoelectrical power plant of 350 MW. In this power plant, the water flow per pipeline for a half of condenser oscillates around 7 m{sup 3}/s (14 m{sup 3}/s per power generating unit). In this analysis, we present the techniques used to measure large flows of water with high accurately, as well as the computational model for water circulating system using PIPE FLO and the results of practical application techniques. [Spanish] La medicion precisa de grandes flujos de agua, sigue siendo un reto en los problemas de aplicacion de sistemas de agua de circulacion de centrales termoelectricas, entre otras aplicaciones. En este articulo, se presenta una metodologia para el analisis de sistemas de bombeo con grandes flujos de agua en centrales termoelectricas, asi como, su aplicacion practica y los resultados obtenidos en los ductos de agua de circulacion de una central generadora con unidades de 350 MW. En esta central, los flujos por caja de agua oscilan alrededor de los 7 m{sup 3}/s (14 m{sup 3}/s por unidad generadora). En el analisis, se presentan las tecnicas utilizadas para medir con precision grandes flujos de agua (tubo de Pitot), asi como, el modelado del sistema de agua de circulacion por medio de un paquete computacional (PIPE FLO) y resultados obtenidos de la aplicacion de dichas tecnicas.

  13. Thermal analysis for energy consumption reduction in cooling water systems; Analisis termico para la reduccion del consumo de energia en sistemas de agua de enfriamiento

    Energy Technology Data Exchange (ETDEWEB)

    Picon Nunez, Martin [Instituto de Investigaciones Cientificas, Universidad de Guanajuato, Guanajuato (Mexico); Quillares Vargas, Luis [Tecnopinch, S. A. de C. V., (Mexico)

    1998-12-31

    This paper presents the fundamental principles for the thermal analysis of cooling water systems in processing plants. In existing heat dissipating networks this methodology application allows the identification of opportunities for reducing the energy consumption used for cooling water pumping. The methodology is based on the determination of the minimum cooling water flow as a function of the installed heat exchange capacity, subjected to the restrictions of the maximum allowed temperature elevation. The methodology application to real systems, has resulted in saving 20% of the total energy consumed in cooling water pumping. [Espanol] En este trabajo se presentan los principios fundamentales para el analisis termico de sistemas de enfriamiento en plantas de proceso. En redes de eliminacion de calor existentes, la aplicacion de esta metodologia permite identificar oportunidades para reducir el consumo de energia utilizada para el bombeo del fluido enfriante. La metodologia se basa en la determinacion del flujo minimo de agua de enfriamiento en funcion de la capacidad de transferencia de calor instalada, sujeta a las restricciones de maximo incremento de temperatura permitido. La aplicacion de la metodologia a sistemas reales, ha resultado en ahorros del 20% del total de la energia que se consume en el bombeo del agua de enfriamiento.

  14. Analysis of the indices of thermal comfort for the conditions of the Mexican Republic; Analisis de los indices de confort termico para las condiciones de la republica mexicana

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes Freixanet, Victor; Rodriguez Viqueira, Manuel [Universidad Autonoma Metropolitana - Unidad Azcapotzalco (Mexico)

    2009-07-15

    The objective of this article is to analyze different indices of thermal comfort for the Mexican Republic. Among them the Fanger (PMV and PPD) physiological methods of comfort and the new effective temperature index are included. The standard effective temperature (SET), as well as the adaptive methods of Humphreys and Nicol, Auliciems, De Dear and Brager. A comparative analysis is done of the different indices through thematic maps determined by interpolation, using a climatic data base of 700 cities obtained from the observatories and stations of the National Meteorological Service. This article pretends to establish general criteria of the thermal comfort to later define design strategies for each one of the climatic regions of the Mexican Republic. [Spanish] El objetivo de este articulo es analizar distintos indices de confort termico para la Republica Mexicana. Entre ellos se incluyen los metodos fisiologicos de confort de Fanger (PMV y PPD), el indice de nueva temperatura efectiva. La temperatura efectiva estandar (SET), asi como los metodos adaptativos de Humphreys y Nicol, Auliciems, De Dear y Brager. Se hace un analisis comparativo de los distintos indices a traves de mapas tematicos determinados por interpolacion, usando una base de datos climaticos de 700 ciudades obtenidos de los observatorios y estaciones del Servicio Meteorologico Nacional. Este articulo presenta establecer criterios generales del confort termico para posteriormente definir estrategias de diseno para cada una de las regiones climaticas de la Republica Mexicana.

  15. Computational package for the dynamic analysis of synchronous generators and their controls; Paquete computacional para el analisis de generadores sincronos y sus controles

    Energy Technology Data Exchange (ETDEWEB)

    Perez Guillen, Jesus Artemio

    1997-12-31

    This thesis presents a computational package for the dynamic analysis of synchronous generators and their controls in a machine - infinite bus system. The package is integrated by a graphic interface for Windows environment and several models for the different components of the generation system. The development of the graphic interface was carried out with object oriented programming under Windows environment, available from Borland C++, which generates a group of menus that integrates an environment of interactive and versatile simulation. The package contains mathematical models of third, fourth, fifth and sixth order for synchronous generators of round and salient poles. Several mathematical models for the excitation systems DC1A, AC1A and ST1A, according to the IEEE classification, are included. Models for thermal and hydraulic turbines with governor of speed are also included, as well as a mathematical model for the power system stabilizer and magnetic saturation on synchronous generators. Numerical methods like Euler, Modified Euler and Runge Kutta of second and fourth order are used to solve the characteristics differential equations of the system under study. Algorithms for graphic generation includes phasor diagram, capability and saturation curves for synchronous machine. Computer models are validated and sensitivity analysis is carried out in order to assess the ef ect of type of model for synchronous machine, excitation systems, power system stabilizer, magnetic saturation in the synchronous generator and different numerical methods of integration. The computational package is useful in teaching and research on the dynamic response of synchronous machines and their controls. [Espanol] En este trabajo se presenta el desarrollo de un paquete computacional para el analisis dinamico de generadores sincronos y sus controles en el esquema de una unidad de generacion - bus infinito. El paquete esta integrado por una interfaz grafica para ambiente Windows y un

  16. Analisis del contenido curricular de los Documentos Normativos del Programa de Ciencias en el area de biologia para la escuela superior del sistema de educacion publica de Puerto Rico: 1993-2012

    Science.gov (United States)

    Davila Montanez, Melissa

    Esta investigacion de naturaleza cualitativa se ocupo de realizar un analisis de contenido documental de los Documentos Normativos del Programa de Ciencias en el area de biologia de la escuela superior del sistema de educacion publica de Puerto Rico del periodo 1993-2012. Los documentos analizados fueron: Guia Curricular, 1995; Marco Curricular, 2003; Estandares de Excelencia, 1996, 2000 y Estandares de Contenido y Expectativas de Grado, 2007. Se indago si hubo cambios en significados en los Componentes Estructurales: Naturaleza de la ciencia, Paradigmas para la ensenanza de la ciencia, Funcion del curriculo formal, Mision de la ensenanza de la ciencia; Contenidos, destrezas y competencias, Estrategias de ensenanza y Evaluacion/Assessment del aprendizaje. El analisis sugiere que no hubo cambios sustanciales en los significados de los Componentes Estructurales. Los documentos estudiados muestran mayormente caracteristicas similares, aunque los documentos mas recientes eran mas descriptivos, explicativos y especificos.

  17. Development of a tool for the analysis and diagnosis in real time of centrifugal pumps; Desarrollo en una herramienta para el analisis y diagnostico en tiempo real de bombas centrifugas

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco, J.J.; Aviles, J.J.; Zaleta, A.; Olivares, A. [Facultad de Ingenieria Mecanica, Electrica y Electronica (FIMEE), Universidad de Guanajuato (Mexico)

    2007-11-15

    In this paper the development of a computer tool for the analysis of centrifugal pumps is presented. This tool allows the user to analyze the performance of the pump by means of the analysis of the behavior curves at its design conditions, reference and operation. In order to realize the analysis it is necessary that the user feeds the tool with the missing and necessary information according to norm ASME PTC 8.2 and under the specified conditions of calibration of the same norm, to eliminate possible errors in the results, a bad qualification or erroneous acquisition of the signals. The system must early be fed with the polynomials of the behavior curves of the pump in its design conditions to later correct the behavior based on a velocity of present operation. [Spanish] En este trabajo se presenta el desarrollo de una herramienta computacional para el analisis de bombas centrifugas. Dicha herramienta permite al usuario analizar el desempeno de la bomba mediante el analisis de las curvas de comportamiento en sus condiciones de diseno, referencia y operacion. Para realizar el analisis es necesario que el usuario alimente la herramienta con la informacion faltante y necesaria de acuerdo a la norma ASME PTC 8.2 y bajo las condiciones de calibracion especificadas en la misma norma, para eliminar posibles errores en los resultados a una mala calificacion o adquisicion erronea de las senales. El sistema tiene que ser anticipadamente alimentado con los polinomios de las curvas de comportamiento de la bomba en sus condiciones de diseno para posteriormente corregir el comportamiento en funcion de una velocidad de operacion actual.

  18. Choice and the cost and benefit analysis of one solar system of renewable energy for the Tepozan Park; Seleccion y analisis costo-beneficio de un sistema de energia renovable para el parque Tepozan

    Energy Technology Data Exchange (ETDEWEB)

    Lopez P, J. Manuel A; Sheinbaum P, Claudia [Instituto de Ingenieria de la UNAM, Mexico, D. F. (Mexico)

    2000-07-01

    This article is about the choice process and the cost and benefit analysis of one solar photovoltaic system for the Tepozan Park, which is a space of ecoturism and ecological education, it is at the Tlalpan District in Mexico, D.F. According to this objective, we start with an introduction related to general conditions in the Park and we talk about the energy requirement. Next, the method for the better option choice is shown, this is based on decision analysis of Kepner and Tregoe. The choice option is evaluated according to the main financial tools of the Cost and Benefit Analysis private evaluation. This shows the decision analysis including issued about ecology. Finally, we add a point for the result synthesis, so we can have a complete approach in order to choice a renewable energy. As conclusion is shown the most important costs and benefits, thinking on future decisions about operation and maintenance of the system. [Spanish] En este articulo se presenta el proceso de seleccion y analisis Costo-Beneficio de un sistema de energia solar fotovoltaica para las instalaciones del Parque Tepozan, un espacio de ecoturismo y educacion ambiental, ubicado en la delegacion Tlalpan de Mexico, D.F. Para ello, se da una introduccion de las condiciones generales del parque y de los requerimientos de energia. Posteriormente se presenta un apartado del metodo para la seleccion de la alternativa mas adecuada, sustentado en un analisis de decisiones. La alternativa seleccionada, se somete a una evaluacion de los principales criterios de la evaluacion privada derivada del Analisis Costo Beneficio, con lo que se ilustra el proceso de toma de decision, incluyendo los factores de impacto ambiental. Finalmente, se incorpora un apartado de sintesis de resultados, para aportar un panorama completo en cuanto a la operacion y mantenimiento del sistema dentro del parque.

  19. Vibration analysis to characterize the behavior of fracture rotors operating in line; Analisis de vibracion para caracterizar el comportamiento de rotores fracturados operando en linea

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Illescas, Rafael

    2001-07-01

    , in other words. Unstable response behavior is quite sensitive to such nonlinear parameters. A general overview in this area is presented as a part of a multidisciplinary study. [Spanish] En este trabajo se presenta un analisis en tres enfoques: teorico, numerico y experimental, del comportamiento dinamico y de la estabilidad vibratoria de un sistema rotor chumacera conteniendo una grieta transversal localizada a medio tramo de la longitud axial del eje. La presencia de una grieta transversal es considerada mediante la modelacion de la variacion periodica de la rigidez estructural del rotor, la cual se expresa en funcion del tiempo (o posicion angular). El amortiguamiento del sistema incluye un amortiguamiento externo debido al fluido dentro del cual se encuentra el rotor girando y, el mas significativamente, un amortiguamiento viscoso originado por la pelicula de aceite en las chumaceras. El problema en estudio consiste en un rotor extendido del tipo Jeffcott, el cual tiene un disco al centro y chumaceras hidrodinamicas identicas en los dos extremos. Un aspecto innovador que aumenta la complejidad del analisis es que se incluye el efecto que tiene la masa del eje en cada una de las chumaceras en los extremos, ademas del efecto obvio de la masa del disco. Se hace una analisis numerico de la estabilidad lineal del sistema incluyendo todos los aspectos mencionados mediante la teoria de Floquet. Algunos resultados son comparados con los obtenidos por otros investigadores en este campo como Gasch, Meng y otros. El sistema parametricamente excitado resultante es analizado utilizado una solucion de perturbacion lineal del sistema. El sistema de ecuaciones se encuentra utilizando terminos complejos y ha sido representado y escrito en programas de computo en MATLAB desarrollados por el autor de la tesis para calcular la estabilidad lineal del problema. Varias configuraciones de rotores simples y reales son estudiados con el fin de ilustrar las propiedades basicas de rotores

  20. Analysis of efficiency of a solar dryer tunnel type of mango pulp; Analisis de la eficiencia de un secador solar tipo tunel para pulpa de mango

    Energy Technology Data Exchange (ETDEWEB)

    Chagoyan Serrano, Jose [Universidad Autonoma de Baja California Sur, La Paz, Baja California Sur (Mexico)

    2000-07-01

    A new method to assess the performance of a solar dryer is presented. It describes energy efficiency indicators to improve a commercial dryer design. First, a preliminary dryer design procedure is described step by step. Then, two different modes of a tunnel dryer are investigated: Batch and semi-continue operations. The results of the analysis show that, the thermal efficiency is not sufficient to rate de dryer performance. It is necessary to include the productivity of the drying process and the quality of the dried fruit. The drying process and productivity tend to go hand-in-hand but in opposite directions. That is to say, raising the thermal efficiency reduce the process productivity and conversely. The analysis also suggests that an agreement between the efficiency, productivity and the quality must be specified in the drier design. [Spanish] Se presenta un procedimiento nuevo para evaluar la operacion de un secador solar, con el cual se precisan indicadores de la eficiencia que pueden ser utiles para mejorar el diseno del equipo. Se empieza por describir los pasos de un procedimiento de diseno preliminar de un sistema de secado. Despues, se analizan cualitativamente dos secadores: uno que opera por lotes y el otro de modo semicontinuo. Los resultados del analisis muestran que, la eficiencia termica del equipo no es un criterio suficiente para evaluar su operacion; tambien se requiere tomar encuenta la productividad del proceso de secado y la calidad del producto final. Se concluye que la eficiencia termica y la productividad del proceso son conceptos encontrados. Es decir, la eficiencia termica del equipo no es un criterio suficiente para evaluar su operacion; tambien se requiere tomar en cuenta la productividad del proceso de secado y la calidad del producto final. Se concluye que la eficiencia termica y la productividad del proceso son conceptos encontrados. Es decir, la eficiencia termica solo se puede aumentar a costa de la productividad y viceversa

  1. STABILIZED PINCH MACHINE

    Science.gov (United States)

    Anderson, O.A.

    1962-04-24

    A device for heating and confining a high temperature gas or plasma utilizing the linear pinch effect is described. The pinch discharge produced is the form of an elongated cylinder. The electrical discharge current is returned in parallel along an axial and a concentric conductor whereby the magnetic field of the conductors compresses and stabilizes the pinch discharge against lateral instability. (AEC)

  2. Un modelo de equilibrio general aplicado a Baleares: analisis economico de la reasignacion intrasectorial del aqua para uso agricola

    OpenAIRE

    Tirado B., Dolores; Gomez G., Carlos M.; Lozano, Javier

    2006-01-01

    En este articulo analizamos las ganancias potenciales en bienestar asociadas al establecimiento de un mercado de derechos sobre aqua para uso agricola. Frente a la tradicional asignacion administrativa del recurso, los intercambios voluntarios de derechos entre los distintos sectores agricolas confieren la flexibilidad necesaria para hacer frente a las sequias ciclicas que caracterizan el regimen hidrico de Baleares. Para simular el funcionamiento del mercado propuesto hemos contruido un Mode...

  3. Analisi matematica

    CERN Document Server

    Canuto, Claudio

    2014-01-01

    Il presente testo intende essere di supporto ad un secondo insegnamento di Analisi Matematica in quei corsi di studio (quali ad esempio Ingegneria, Informatica, Fisica) in cui lo strumento matematico parte significativa della formazione dell'allievo. I concetti e i metodi fondamentali del calcolo differenziale ed integrale in più variabili, le serie di funzioni e le equazioni differenziali ordinarie sono presentati con l'obiettivo primario di addestrare lo studente ad un loro uso operativo, ma critico. L'impostazione didattica dell'opera ricalca quella usata nel testo parallelo di Analisi Matematica I. La modalità di presentazione degli argomenti ne permette un uso flessibile e modulare. Lo stile adottato privilegia la chiarezza e la linearità dell'esposizione. Il testo organizzato su due livelli di lettura. Uno, più essenziale, permette allo studente di cogliere i concetti indispensabili della materia, di familiarizzarsi con le relative tecniche di calcolo e di trovare le giustificazioni dei principali r...

  4. Methodology for the energy analysis of compressed air systems; Metodologia para analisis energetico de sistemas de aire comprimido

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, T.; Ambriz, J. J.; Romero, H. [Universidad Autonoma Metropolitana-Iztapalapa, Mexico, D. F. (Mexico)

    1992-12-31

    In this paper a methodology for the diagnosis of compressed air systems, for the identification of the potential energy saving is presented. The methodology consists in detecting the largest number of possible ways of energy saving. For this purpose it is divided into three parts: 1. Compressed air generation. 2. Compressed air distribution. 3. Compressed air users. For each one of the parts, the type of information required to perform the diagnosis study, as well as the necessary measuring equipment needed, is indicated. Afterwards, the possible saving ways that can be found and the ones that can be feasible, are analyzed. [Espanol] En este trabajo se presenta una metodologia para diagnosticar sistemas de aire comprimido, para identificar los potenciales de ahorro de energia. La metodologia consiste en detectar el mayor numero de posibles medidas de ahorro, para lo cual se divide en tres partes: 1. Generacion de aire comprimido. 2. Distribucion del aire comprimido. 3 Usuarios de aire comprimido. Para cada una de las partes se indica el tipo de informacion requerida para realizar el estudio de diagnostico, asi como el uso de equipo necesario de medicion. Despues se analizan las posibles medidas de ahorro que se pueden encontrar y las que pueden ser viables.

  5. Monitoring systems for the analysis of vibrations and balance of rotary machines; Sistemas de monitorizacion para el analisis de vibraciones y balanceo de maquinas rotatorias

    Energy Technology Data Exchange (ETDEWEB)

    Serrano R, Luis E; Ramirez Solis, J. Antonio; Munoz Q, Rodolfo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2004-07-01

    Often, the rotary equipment faults appear as an abnormal vibration or a change in the characteristic vibration pattern of each machine. From here the importance of counting on tools that allow to acquire and to analyze the vibration signals of the equipment while it is in operation. The Gerencia de Turbomaquinaria has worked in this field since the end of the Seventies, developing diagnosis systems based on personal computers that allow the monitoring of the dynamic behavior of the rotary equipment. The main system of this type that the Instituto de Investigaciones Electricas (IIE), nowadays offers, is the Computerized System for Dynamic Analysis, also known by its abbreviation in Spanish as: SICAD II. This was designed under the requirements of the Comision Federal de Electricidad (CFE) to collect, measure and analyze vibration data of rotary equipment. It is also used in the balance, fault diagnosis and the solution of problems in rotary equipment. The system SICAD II is portable and versatile system with which vibrations are acquired, measured and analyzed by means of the presentation of the data in graphical formats of different type and application. [Spanish] A menudo, las fallas en los equipos rotatorios se manifiestan como una vibracion anormal o como un cambio en el patron de vibraciones caracteristico de cada maquina. De ahi la importancia de contar con herramientas que permitan adquirir y analizar las senales de vibracion de los equipos mientras estan en operacion. La Gerencia de Turbomaquinaria ha trabajado en este campo desde finales de la decada de los setenta, desarrollando sistemas de diagnostico basados en computadoras personales que permiten monitorear el comportamiento dinamico de los equipos rotatorios. El principal sistema de este tipo que ofrece, actualmente, el Instituto de Investigaciones Electricas (IIE) es el Sistema Computarizado para Analisis Dinamico, conocido tambien por su abreviacion como: Sicad II. Este fue disenado bajo los

  6. Empleo, productividad y salarios en Mexico: Un analisis de corto y de largo plazo para el sector manufacturero

    OpenAIRE

    Maria de Lourdes Rodriguez Espinosa; Ramon A. Castillo Ponce

    2009-01-01

    En este documento se evalua la existencia de relaciones estadisticamente significativas, de largo y de corto plazo, entre los salarios, la productividad y el empleo en el sector manufacturero mexicano. En particular se estima una ecuacion de cointegracion y una de ciclo comun para las variables antes mencionadas. Encontramos que, en el largo plazo, los salarios comparten movimientos comunes con la productividad y el empleo, pero no asi en el corto plazo. Estos resultados sugieren que el merca...

  7. Analisis de la estructura productiva y de ingreso-gasto del estado de Nuevo Leon para el ano 2004

    OpenAIRE

    Joana Cecilia Chapa Cantu; Erick Rangel Gonzalez

    2010-01-01

    En este articulo se analiza la estructura productiva y de ingreso-gasto del estado de Nuevo Leon mediante la construccion de una Matriz de Contabilidad Social y el calculo de los efectos multiplicadores de los sectores productivos sobre el ingreso de los hogares para el ano 2004. Una de las caracteristicas mas importantes de la Matriz de Contabilidad Social es que fue elaborada con base en los microdatos de la Encuesta Nacional de Ingreso y Gasto de los Hogares. Los principales resultados ind...

  8. Tipologias y analisis del escenario actual de las energias renovables.: propuesta futura para el caso del territorio catalan

    OpenAIRE

    Latorre Garrido, David

    2011-01-01

    En las últimas décadas el contexto internacional ha sido cada vez más sensible a los efectos del calentamiento global del planeta, que se ha denominado “cambio climático”. En éste sentido se redactó el Protocolo de Kyoto, en el que los gobiernos se comprometieron a hacer un esfuerzo para reducir las emisiones de gases de efecto invernadero. El protocolo apuntaba a los combustibles fósiles (gas natural, petróleo y carbón) como los principales responsables de dichas emisiones, combustibles ...

  9. Uso y adaptación de un sistema de Deep Learning para analisis de imagenes en un Supercomputador

    OpenAIRE

    Arias Navarro, Borja

    2016-01-01

    Este proyecto es el estudio de la implantación de un sistema de DeepLearning (DeepLearning4J) en Spark4MN y las pruebas de rendimiento del Framework escogido. Se usa una implementación de la clasificación de dígitos escritos a mano para el estudio de escalabilidad. This project is about the implantation of a DeepLearning system (DeepLearning4J) on top of Spark4MN and the performance tests of the framework chosen. To do the benchmarks a classification of hand written digits has been impleme...

  10. Chemical processes of coal for use in power plants. Part 1: Approximate analysis and associated indexes of pulverized coal; Procesos quimicos del carbon para su uso en centrales termoelectricas. Parte 1: Analisis aproximado e indices asociados del carbon pulverizado

    Energy Technology Data Exchange (ETDEWEB)

    Altamirano-Bedolla, J. A.; Manzanares-Papayanopoulos, E.; Herrera-Velarde, J. R. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: emp@iie.org.mx

    2010-11-15

    The usage of hydrocarbons, such as natural gas, oil products and coal, will be the main source of energy to the mankind for next generations. Therefore, the actual research and technological developments point out to employ with high efficiency those fuels. The main interests are to release most of the energy as possible and to guide the combustion reactions. It is well known that during the combustion process of coal, the chemical energy is converted to thermal energy, which it allows the steam production, and therefore to produce energy through an electric generator. The main interest of the work presented here is to study the behavior of the coal combustion processes in function of the approximate analysis and some associate indices of that analysis, to point out the optimization of the coal usage as main fuel in electrical power generation plants. [Spanish] El uso de hidrocarburos como son el gas natural, los derivados del petroleo y el carbon mineral, continuara siendo en las proximas decadas la principal fuente de energia de la humanidad. Por consiguiente, la investigacion cientifica y los desarrollos tecnologicos actualmente se enfocan en emplear de manera mas eficiente dichos combustibles, satisfaciendo entre otros factores, dos intereses principales: liberar la mayor cantidad de energia, reduciendo al minimo el material combustible no quemado, y direccionar las reacciones del proceso de combustion para minimizar la cantidad de productos no deseados resultantes de la reaccion. A traves de los procesos quimicos de combustion del carbon, se transforma la energia quimica a energia termica, lo que permite la produccion de vapor para a su vez impulsar una turbina la cual esta acoplada a un generador electrico. El objetivo del presente trabajo es el estudio del comportamiento de los procesos quimicos que se llevan a cabo durante las reacciones de combus-tion del carbon en funcion del analisis aproximado y de los indices asociados resultantes de dicho analisis; lo

  11. Irreversibility analysis of non isothermal flat plate solar collectors for air heating with a dimensionless model; Analisis de las irreversibilidades en colectores solares de placas planas no isotermicos para calentamiento de aire utilizando un modelo adimensional

    Energy Technology Data Exchange (ETDEWEB)

    Bracamonte-Baran, Johane Hans; Baritto-Loreto, Miguel Leonardo [Universidad Central de Venezuela (Venezuela)]. E-mails: johanehb@gmail.com; johane.bracamonte@ucv.ve; miguel.baritto@ucv.ve

    2013-04-15

    The dimensionless model developed and validated by Baritto and Bracamonte (2012) for the thermal behavior of flat plate solar collector without glass cover is improved by adding the entropy balance equation in a dimensionless form. The model is solved for a wide range of aspect ratios and mass flow numbers. A parametric study is developed and the distribution of internal irreversibilities along the collector is analyzed. The influence of the design parameters on the entropy generation by fluid friction and heat transfer is analyzed and it is found that for certain combinations of these parameters optimal thermodynamic operation can be achieved. [Spanish] En el presente trabajo, el modelo adimensional desarrollado y validado por Baritto y Bracamonte (2012) para describir el comportamiento termico de colectores solares de placas planas sin cubierta transparente, se complementa con la ecuacion adimensional de balance de entropia para un elemento diferencial de colector solar. El modelo se resuelve para un amplio rango de valores de relaciones de aspecto y numero de flujo de masa. A partir de los resultados del modelo se desarrolla un analisis detallado de la influencia de estos parametros sobre la distribucion de irreversibilidades internas a lo largo del colector. Adicionalmente se estudia la influencia de estos parametros sobre los numeros de generacion de entropia por friccion viscosa, por transferencia de calor y total. Se encuentra que existen combinaciones de los parametros antes mencionados, para los cuales, la operacion del colector es termodinamicamente optima para numeros de flujo de masa elevados.

  12. Analisis Statistika dengan SPSS

    OpenAIRE

    Mustari, Kahar

    2012-01-01

    Buku ini membahas tentang berbagai model analisis statistika yang dapat digunakan dalam berbagai bidang penelitian. Pembahasan buku ini dilengkapi pula dengan penerapan analisis statistika yang menggunakan program SPSS versi 20 sehingga memudahkan pembaca untuk menerapkannya. Oleh karena itu, buku ini penting dibaca oleh mahasiswa atau peneliti yang melakukan pengolahan data penelitian.

  13. Revision curricular a partir de un analisis comparativo de las discrepancias en los curriculos de una escuela de optometria en Puerto Rico con las competencias requeridas para las agencias de revalida y acreditacion 2004

    Science.gov (United States)

    Rivera Pacheco, Andres

    El proposito de esta investigacion, un estudio cualitativo de caso, fue comparar y contrastar el curriculo vigente de la Escuela de Optometria de la UIAPR con las competencias y estandares requeridos por las agencias de acreditacion y de revalida. Con este proposito, decidimos realizar una revision y un analisis de documentos: el prontuario de cada uno de los cursos de los curriculos implantados en el 1993 y en el 2001; las competencias y estandares establecidos por las agencias de revalida y de acreditacion; y las estadisticas en las que se analiza el porcentaje de estudiantes que aprueban cada una de las partes de los examenes de revalida entre el 1998 al 2003. Se realizaron entrevistas dirigidas para dar apoyo y complementar la revision y el analisis de estos documentos. Los participantes de las entrevistas fueron tres estudiantes de la clase de optometria del 2004 (ultima clase del curriculo del 1993); tres estudiantes de la clase de optometria del 2005 (primera clase graduanda del curriculo vigente) y tres profesores y/o directores de los Departamentos de Ciencias Basicas, Ciencias Clinicas y Cuidado al Paciente. Esta investigacion se enmarco en el modelo de evaluacion curricular de discrepancia de Malcolm Provus y en el modelo de desarrollo basado en competencias. Uno de los hallazgos mas importantes del estudio es que los cambios que se implantaron al curriculo del 2001 no han logrado que los estudiantes mejoren su ejecucion en los examenes de revalida. Por otro lado, se encontro que el curriculo vigente atiende completamente los estandares de la practica de Optometria, pero no las competencias. Esta informacion fue validada mediante el uso de una tabla de cotejo para el analisis de los cursos y de la informacion obtenida de las entrevistas. El estudio determina y concluye que existen discrepancias entre los prontuarios de los cursos del curriculo y las competencias requeridas por la agencia de revalida. Segundo, que el Departamento de Ciencias Basicas es el

  14. Analysis of the methods for the achievement of comfort conditions of humidity and temperature in energetically efficient designs; Analisis de los mtodos para lograr condiciones de confort higrotermico en disenos energeticamente eficientes

    Energy Technology Data Exchange (ETDEWEB)

    Mesa A., N. A.; Morillon G., D. [Division de Estudios de Posgrado de la Facultad de Arquitectura, Universidad Nacional Autonoma de Mexico (Mexico)

    1997-12-31

    This paper presents the analysis of the tools commonly utilized in Bioclimatic Design, for the achievement of humidity an temperature comfort conditions in architectonic spaces. The analysis was performed by means of field studies and experimentally for different sport activities, carried out in spaces designed for each purpose. In the experimental part, inside ambient temperature and relative humidity were measured in the different spaces where sport activities were conducted, such as calisthenics, dance, judo, wrestling, weight lifting, boxing, basket-ball, volley-ball, gymnastics and fencing. At the same time an inquiry was conducted among their occupants in respect to the thermal sensation they experimented while conducting such activities. The results obtained in the inquiry were compared with the results reported by other researchers, by means of tables and psychometric diagrams as optimum values for temperature comfort. As a conclusion it was decided that the graphic and mathematical methods analyzed, are based on a sedentary activity, therefore in using them for the design of spaces for different activities uncomfortable conditions are experimented with the consequential necessity of air conditioning, which implies energy consumption and the corresponding expenditure, lastly it is necessary to adapt these tools, that is, consider the activity that is going to be performed in the buildings. [Espanol] En este documento se presenta el analisis de las herramientas, comunmente utilizadas en Diseo Bioclimatico, para lograr el confort higrotermico de espacios arquitectonicos, el analisis se realizo mediante estudios de campo y experimental, para diversas actividades deportivas, llevadas a cabo en espacios disenados para ello. En la parte experimental, se tomaron mediciones de temperatura y humedad relativa internas, de los distintos espacios en los cuales se desarrollaban las actividades deportivas, tales como calistenia, danza, judo, lucha, trabajo con pesas

  15. Introduction to Pinch Technology

    DEFF Research Database (Denmark)

    Rokni, Masoud

    efficient as it should be? How can new projects be evaluated with respect to their energy requirements? What changes can be made to increase the energy efficiency without incurring any cost? What investments can be made to improve energy efficiency? What is the most appropriate utility mix for the process......? How to put energy efficiency and other targets like reducing emissions, increasing plant capacities, improve product qualities etc, into a one coherent strategic plan for the overall site? All these questions and more can be answered with a full understanding of Pinch Technology and an awareness of...... the available tools for applying it in a practical way. The aim here is to provide the basic knowledge of pinch technology concept and how it can be applied across a wide range of process industries. The pinch technology was proposed firstly for optimization of heat exchangers and therefore it is...

  16. Staged theta pinch experiments

    International Nuclear Information System (INIS)

    Two implosion heating circuits are being experimentally tested. The principal experiment in the program is the 4.5-m-long Staged Theta Pinch (STP). It uses two relatively low energy (50kJ and 100 kJ), high voltage (125 kV) capacitor banks to produce the theta pinch plasma inside the 20 cm i.d. quartz discharge tube. A lower voltage (50 kV), higher energy (750 kJ) capacitor bank is used to contain the plasma and provide a variable amount of adiabatic compression. Because the experiment produces a higher ratio of implosion heating to compressional heating than conventional theta pinches, it should be capable of producing high temperature plasmas with a much larger ratio of plasma radius to discharge tube radius than has been possible in the past. The Resonant Heating Experiment (RHX) in its initial configuration is the same as a 0.9-m-long section of the high voltage part of the STP experiment and all the plasma results here were obtained with the experiment in that configuration. Part of the implosion bank will be removed and a low inductance crowbar added to convert it to the resonant heating configuration. (U.K.)

  17. Z-Pinch Fusion Propulsion

    Science.gov (United States)

    Miernik, Janie

    2011-01-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Shorter trips are better for humans in the harmful radiation environment of deep space. Nuclear propulsion and power plants can enable high Ispand payload mass fractions because they require less fuel mass. Fusion energy research has characterized the Z-Pinch dense plasma focus method. (1) Lightning is form of pinched plasma electrical discharge phenomena. (2) Wire array Z-Pinch experiments are commonly studied and nuclear power plant configurations have been proposed. (3) Used in the field of Nuclear Weapons Effects (NWE) testing in the defense industry, nuclear weapon x-rays are simulated through Z-Pinch phenomena.

  18. PENGKAJIAN MISCLASSIFICATION PADA ANALISIS DISKRIMINAN

    OpenAIRE

    Drs. Raupong, M.Si.

    2003-01-01

    Misclassification adalah pengamatan yang pengelompokannya tidak benar. Pengamatan tersebut kemungkinanan besra berpengaruh dalam analisis diskriminan. Dalam melakukan analisis diskriminan sebaiknya nilai total peluang misclassification dalam pengelompokan sekecil-kecilnya atau nilai laju galat terlihat (Rate Apparent Error atau APER) terkecil. Penggunaan pendekatan penghilangan pengamatan misclassification untuk meperoleh nilai APER terkecil yang tidak mempengaruhi pengelompokkan pengamatan ...

  19. Simulation for double shell pinch

    Institute of Scientific and Technical Information of China (English)

    Wang Gang-Hua; Hu Xi-Jing; Sun Cheng-Wei

    2004-01-01

    Basic shock phenomena are presented in a composite pinch, a hybrid of the Z-pinch. The successive transfer of current within the plasma structure is demonstrated by our calculations. Properties of the shock wave are described.The current distribution between the two shells after the outer shell hitting the inner shell is also discussed.

  20. Technology of field reversed pinch

    International Nuclear Information System (INIS)

    This paper presents a review of field-reversed pinch technology. It covers the basic design requirements for various components involved in a field-reversed pinch device, such as circuit, switch, triggering system, transmission line, load assembly and power supply. Precautions against electric interferences are also mentioned

  1. Papel de los consorcios entre microorganismos fotótrofos y analisis de su poténcial para bioreparar ambientes contaminados por metales pesados

    OpenAIRE

    Burgos Arcos, Alvaro Javier

    2013-01-01

    En este trabajo se ha evaluado la capacidad bioreparadora de tres cianobacterias, dos de ellas procedentes de la Colección de Cultivos Pasteur: Spirulina sp. PCC 6313 (Sp) y Chroococcus sp. 9106 PCC (Ch), y dos aisladas del delta del Ebro: una cianobacteria DE2011 (Ge) y una microalga DE2009 (Sc). Por primera vez, se ha ensayado la capacidad de los consorcios, asociaciones de microorganismos, para tolerar o resistir (T-R) la presencia de metales y para determinar su capacidad para captarlo...

  2. Uma nova pinça regulável para a produção de lesões por esmagamento do nervo ciático do rato A new adjustable pinch designed for producing crush nerve injuries in the sciatic nerve of rats

    Directory of Open Access Journals (Sweden)

    Vanessa Vilela Monte-Raso

    2009-01-01

    Full Text Available OBJETIVO: Foi nosso objetivo, desenvolver uma pinça regulável que permite produzir uma lesão com carga conhecida, num segmento de 5 mm de comprimento do nervo isquiático de ratos. MÉTODOS: O material escolhido para confecção da pinça foi o aço inoxidável, pela sua maior durabilidade e possibilidade de esterilização com soluções anti-sépticas, quase sempre corrosivas. A carga de esmagamento da pinça é regulável, pelo aumento ou diminuição da tensão da mola que a aciona, por meio de um parafuso de regulagem de calibração, feita com uma célula de carga. RESULTADO: A pinça foi utilizada em investigações experimentais e mostrou-se tão eficiente quanto as máquinas de ensaio e de peso morto anteriormente utilizadas. CONCLUSÃO: A pinça desenvolvida apresenta vantagens de ser portátil, de fácil manuseio, baixo custo e permite padronização da carga aplicada.OBJECTIVE: A new adjustable pinch has been developed for producing a crush injury, with a previously known load of 5 kg, on a 5 mm-long segment of the nerve. METHODS: Stainless steel was the material selected for building the pinch due its durability and possibility of sterilization with anti-septic substances, which are often corrosive. The crushing load of the pinch is adjustable by increasing or decreasing the tension of the spring by means of a screw used for calibration, which is performed by a load cell. RESULT: This pinch has been used in a few experimental investigations and was shown to be as efficient as both the universal testing machine and the dead weight machine, previously used. CONCLUSION: The developed pinch has the advantages of being portable and user-friendly. In addition, the pinch is cheap and allows for the standardization of the applied load.

  3. Dense-Pinch Photocathode

    Science.gov (United States)

    Asmus, John F.; Lovberg, Ralph H.

    1988-05-01

    A promising approach to the generation of low-emittance e-beams for particle beam and FEL application employs a photoelectron cathode. IF such an e-beam source is to be viable at high power, a high-performance hard-UV illuminator is needed. Toward this end, experiments have been performed by illuminating a metal photocathode with the VUV radiation from a laser-guided gas-embedded high-density high-Z pinch. Such a VUV source is interesting because the plasma is created at high density and is optically thick. Thus, it is both a stable and an efficient radiator. Coupled with a copper photocathode it has generated a-beam current densities up to 60 A/sq-cm. The test device has been modified to utilize a pinch formed from a liquid jet in vacuum, rather than the laser-guided discharge in high-pressure gas. This is more suitable for rep-rate operation as it dispenses with the VUV-absorbing interposed gas, the channel-forming laser, and gas transport at high average power. A decane-jet device has been tested at 10 Hz with a peak pulse VUV power of 100 MW.

  4. Alternative analysis to increase the power in combined-cycle power plants; Analisis de alternativas para el incremento de potencia en plantas termoelectricas de Ciclo Combinado

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco Cruz, Hector; Arriola Medellin, Alejandro M. [Gerencia de Procesos Termicos, Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: hpacheco@iie.org.mx; aarriola@iie.org.mx

    2010-11-15

    The electricity industry traditionally had two thermodynamic cycles for power generation: conventional steam turbine (Rankine cycle) used to supply a base load during the day, and gas turbines (Brayton cycle), for its speed response, normally used to cover peak loads. However, to provide variable peak loads, the gas turbine, as a volumetric machine is affected by the change in air density by changing the combustion temperature. This paper shows the scheme of integration of both systems, that it's known as combined cycle and the different options that would have these power plants, to maintain or increase their power in variable ambient conditions. It analyzes different options, such as: 1. Supplementary fire in the stove. 2. Air cooling intake in the gas turbine (evaporation system or mechanical system). 3. Steam injection in the combustion chamber. [Spanish] La industria electrica tradicionalmente a contado con dos ciclos termodinamicos para generacion electrica: las turbinas convencionales de vapor (ciclo de Rankine) se utilizan para suministrar una carga base durante el dia, y las turbinas de gas (ciclo de Brayton), por su rapidez de respuesta, se utilizan normalmente para cubrir las cargas pico. Sin embargo, para suministrar las cargas variables pico, la turbina a gas, por ser una maquina volumetrica, se ve afectada por el cambio de la densidad del aire de combustion al cambiar la temperatura ambiente. En este trabajo se muestra el esquema de integracion de ambos sistemas, en lo que se conoce como ciclo combinado y las diferentes opciones que tendrian estas plantas de generacion electrica para mantener o incrementar su potencia en condiciones ambiente variable. Para ello se analizan diferentes opciones, tales como: 1.- Combustion suplementaria en el recuperador de calor. 2.- Enfriamiento del aire de admision a la turbina de gas (mediante un sistema de evaporacion o mediante un sistema mecanico). 3.- Inyeccion de vapor a la camara de combustion. Palabras

  5. Methodology for maintenance analysis based on hydroelectric power stations reliability; Metodologia para realizar analisis de mantenimiento basado en confiabilidad en centrales hidroelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Rea Soto, Rogelio; Calixto Rodriguez, Roberto; Sandoval Valenzuela, Salvador; Velasco Flores, Rocio; Garcia Lizarraga, Maria del Carmen [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2012-07-01

    A methodology to carry out Reliability Centered Maintenance (RCM) studies for hydroelectric power plants is presented. The methodology is an implantation/extension of the guidelines proposed by the Engineering Society for Advanced Mobility Land, Sea and Space in the SAE-JA1012 standard. With the purpose of answering the first five questions, that are set out in that standard, the use of standard ISO14224 is strongly recommended. This approach standardizes failure mechanisms and homogenizes RCM studies with the process of collecting failure and maintenance data. The use of risk matrixes to rank the importance of each failure based on a risk criteria is also proposed. [Spanish] Se presenta una metodologia para realizar estudios de mantenimiento Basado en Confiabilidad (RCM) aplicados a la industria hidroelectrica. La metodologia es una implantacion/ extension realizada por los autores de este trabajo, de los lineamientos propuestos por la Engineering Society for Advanced Mobility Land, Sea and Space en el estandar SAE-JA1012. Para contestar las primeras cinco preguntas del estandar se propone tomar como base los modos y mecanismos de fallas de componentes documentados en la guia para recopilar datos de falla en el estandar ISO-14224. Este enfoque permite estandarizar la descripcion de mecanismos de fallas de los equipos, tanto en el estudio RCM como en el proceso de recopilacion de datos de falla y de mantenimiento, lo que permite retroalimentar el ciclo de mejora continua de los procesos RCM. Tambien se propone el uso de matrices de riesgo para jerarquizar la importancia de los mecanismos de falla con base en el nivel de riesgo.

  6. Analisis Tingkat Efektifitas Mesin Sheeter Dengan Menggunakan Metode Oee (Overall Equipment Effectiveness) Pada Pabrik Pengolahan Latex PT. Perkebunan Nusantara III Kebun Gunung Para

    OpenAIRE

    Stefano, Danny

    2010-01-01

    PT. Perkebunan Nusantara III Kebun Gunung Para merupakan perusahaan yang bergerak dalam pengolahan latex, yang tidak terlepas dari masalah yang berhubungan dengan efektivitas mesin/peralatan yang diakibatkan oleh six big losses. Pada mesin Sheeter I ini masalah yang sering terjadi adalah menurunnya kemampuan kerja dari mesin diakibatkan oleh kurangnya kadar air/buruknya kualitas latex sehingga mengakibatkan menurunnya efisiensi kerja mesin Sheeter I, hal ini mengakibatkan kondisi mesin menjad...

  7. Analisis Faktor yang Mempengaruhi Indeks Prestasi Mahasiswa

    Directory of Open Access Journals (Sweden)

    Putriaji Hendikawati

    2011-12-01

    Full Text Available Penelitian ini dilaksanakan untuk mengungkap dan menganalisis faktor-faktor yangmempengaruhi perolehan indeks prestasi mahasiswa. Populasi penelitian adalahmahasiswa program studi Pendidikan Matematika FMIPA Unnes dan dipilih sampelsebanyak 3 kelas. Pengambilan sampel dilakukan dengan cara stratified cluster randomsamplingdengan sampel penelitian berjumlah 114 mahasiswa.Hasil penelitian menunjukkan bahwa Indeks Prestasi (IP mahasiswa dipengaruhioleh beberapa variabel antara lain: variabel suasana hati, membagi waktu, hubungandengan keluarga, penjelasan dosen, suasana tempat tinggal, kegiatan selain kuliah, bakat,adaptasi lingkungan, pantauan orang tua, perhatian orang tua, pergaulan, makan dan gizi,IQ dan EQ, kemampuan sosialisasi, kondisi keuangan, suasana belajar kampus, pancaindera kemampuan menangkap materi, dan olahraga. Setelahdilakukan analisis faktor danproses reduksi diperoleh5 faktor yang mempengaruhi IP mahasiswa. Lima faktor tersebutadalah Faktor Manajemen Diri, Faktor Lingkungan Sekitar, Faktor Kondisi Eksternal,Faktor Kondisi Fisik dan Faktor Olahraga.Hasil penelitian ini bermanfaat bagi mahasiswa serta para dosen khususnyapenentu kebijakan di jurusan Matematika FMIPA Unnes, untuk mengembangkan sertameningkatkan faktor-faktor yang mempengaruhi IP mahasiswa yang berhubungan dengankebijakan dalam kampus agar dapat memberikan kontribusi positif bagi perolehan IPmahasiswa. Kata kunci: analisis faktor, indeks prestasi, mahasiswa.

  8. Analysis of inflow in geothermal wells to determine their maximum flow; Analisis del influjo en pozos geotermicos para la determinacion de sus flujos maximos

    Energy Technology Data Exchange (ETDEWEB)

    Aragon-Aguilar, Alfonso; Izquierdo-Montalvo, Georgina; Pal-Verma, Mahendra; Santoyo-Gutierrez, Socrates [Instituto de Investigaciones Electricas (Mexico); Moya-Acosta, Sara L [Centro Nacional de Investigacion y Desarrollo Tecnologico (Mexico)

    2009-01-15

    Inflow performance relationships developed for petroleum and geothermal reservoirs are presented. Four of them were selected to be used in this work. Such relationships were developed considering features of a typical geothermal system. The performance of the selected relationships was assessed using data from production tests in several wells of different fields. A methodology is presented to determine the value of the maximum flow (W{sub max}) from the inflow relationships; its application is demonstrated using the data of the 10 production tests. It was found that the calculated value of W{sub max} under stabilization conditions may be related to the reservoir response. In general, there is a good agreement between the calculated values of W{sub max} from the different methods. The differences in the W{sub max} values vary within 10%. It was found that the stability in the calculated values of W{sub max} as a response of the reservoir is a function of the flow magnitude. So, the wells with flow greater than 200 t/h reach the stability of W{sub max} at openings 50% less of their total capacity. [Spanish] Se presentan las relaciones del comportamiento de influjo desarrolladas para yacimientos petroleros y geotermicos. Se seleccionaron cuatro de ellas para usar en este trabajo. Tales relaciones fueron desarrolladas considerando condiciones de un sistema geotermico tipico. Se analizo el comportamiento de las relaciones escogidas utilizando datos de pruebas de produccion de varios pozos de diferentes campos. Se presenta una metodologia para determinar el valor del flujo maximo (W{sub max}) a partir de las relaciones de influjo; se demuestra su aplicabilidad usando los datos de diez pruebas de produccion. Se encontro que el valor de W{sub max} calculado bajo condiciones de estabilizacion se puede relacionar con la respuesta del yacimiento. En general se encuentra buena concordancia entre los valores calculados de W{sub max} usando los diferentes metodos. Las

  9. EVALUACION DE METODOLOGÍAS PARA EL ANALISIS DE PRODUCTOS TÓXICOS DE LA DEGRADACIÓN DE FUNGICIDAS DITIOCARBAMATOS

    Directory of Open Access Journals (Sweden)

    Jairo Arturo Guerrero

    2013-11-01

    Full Text Available Se evaluaron cuatro metodologías para la determinación de etilentiourea y propilentiourea en frutas y hortalizas; se seleccionó y optimizó un método de extracción utilizando una mezcla metanol:agua 3:1 y posterior limpieza con partición liquido-líquido soportada sobre extrelut. La determinación y cuantificación se llevó a cabo utilizando cromatografía liquida de alta eficiencia con detección de arreglo de diodos. La metodología validada es específica y selectiva, con porcentajes de recuperación entre 77,82% y 83,57%, coeficientes de variación menores al 20% y límites de detección entre 0,003 y 0,006 mg.kg-1. Los parámetros estadísticos de linealidad mostraron resultados adecuados en los rangos de concentración evaluados. La metodología es robusta para las variables evaluadas y no se observó efecto matriz. Se encontraron trazas de etilentiourea y propilentiourea en una muestra de tomate y una muestra de papa, respectivamente.

  10. System for the reliability analysis of the electric energy supply; Sistema para el analisis de confiabilidad del suministro de energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Perales, Favio; Martinez, Javier; Huesca, Francisco; Garcia, Norma; Nieva, Rolando [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    A computer tool, developed for the reliability evaluation of the electric energy supply, considering the faults in the generation and transmission systems, is presented. The application of the tool in planning the expansion and operation of the electric systems, the methodology of the solution employed and the various functions it accounts for, are described. At the end some illustrative examples of its applications by means of the studies with a model of representative characteristics of the interconnected national system. [Espanol] Se presenta una herramienta computacional desarrollada para evaluar la confiabilidad del suministro de energia electrica, considerando las fallas en los sistemas de generacion y transmision. Se describen las aplicaciones de la herramienta en la planeacion de la expansion y de la operacion de sistemas electricos, la metodologia de solucion empleada y las diversas funciones con que cuenta. Al final se presentan algunos ejemplos ilustrativos de sus aplicaciones mediante estudios con un modelo de caracteristicas representativas del sistema interconectado nacional.

  11. m=0 Z-Pinch stability reconsidered

    International Nuclear Information System (INIS)

    The m=0 linear stability of the collisionless, small Larmor radius Z-pinch is examined. By using a generalized form of the energy principle it is shown that a finite pressure external gas can stabilize the pinch. Equilibrium skin currents are always destabilizing. Our results clarify why the gas-embedded pinch and Extrap are m=0 stable, whereas the fibre and compressional pinches are not

  12. Application of exergy balances for the analysis of an oil plant; Aplicacion de balances de exergia para el analisis de una planta de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Toral, Miguel Angel; Rangel Davalos, Humberto [Instituto Mexicano del Petroleo (Mexico)

    1996-07-01

    The Mexican oil industry requires of the technological modernization, for this purpose it is planning the optimization of its operations of primary production, among which it stands out the separation and the stabilization. These operations take place in an oil complex which has been planned to be installed in the Mexican Southeastern. This paper shows some of the advances in the installation of the complex of separation, compression and stabilization of crude oil, which was analyzed at the light of the concepts of energy saving and of the second law of thermodynamics. [Spanish] La industria petrolera mexicana requiere de modernizacion tecnologica, para ello se esta planeando la optimizacion de sus operaciones de produccion primaria, entre las que destaca la separacion y estabilizacion. Dichas operaciones se efectuan en un complejo petrolero, mismo que se tiene planeado instalar en el sureste mexicano. Este trabajo muestra algunos de los avances en la instalacion del complejo de separacion, compresion y estabilizacion de petroleo crudo, el cual se analizo a la luz de los conceptos de ahorro de energia y de la segunda ley de la termodinamica.

  13. Methodology for the analysis of electric power systems at harmonic frequencies; Metodologia para el analisis de sistemas electricos a frecuencias armonicas

    Energy Technology Data Exchange (ETDEWEB)

    Silva Farias, Jose Luis

    1989-07-01

    chapter is an historical sketch of the harmonic sources in power systems, as well as the problems that the presence of these cause. For the good performance of the work, its importance must be specified, to have the required data available and to carry out the necessary considerations to simplify the study without including significant errors. These requirements comprise part of chapter two. Chapter three deals, in a summarized way, with the analysis tools and the Standards, as well as with some important considerations with respect to the measurements. In chapter four the models of some electric elements, linear as well as nonlinear are presented. The presence of the capacitors to correct the power factor can originate resonance effects under different schemes of harmonic injection. For this reason, the purpose of chapter five is the specification of the scheme that represents the most severe resonance condition. Chapter six describes the electric arc model, as well as the way the necessary conditions were carried out to approximate the proposed model. Later, chapter seven includes the validation of the electric arc model and emphasizes the importance that the simulation of transients due to maneuvers in the system has. Finally, chapter eight contains the conclusions generated as a result of the research work, as well as the recommendations for future works in the area. [Spanish] La presencia de armonicas es un problema que ha existido durante muchos anos en los sistemas de potencia. Sin embargo, en la epoca actual el aumento en las cargas generadoras de armonicas se ha incrementado considerablemente como respuesta al desarrollo de la industria y de los satisfactores que reclama la vida moderna. Para llevar a cabo este trabajo de investigacion se considera la red electrica de una planta industrial destinada a la produccion de acero, la cual cuenta con tres hornos electricos en arco. La seleccion de este sistema es muy importante ya que los hornos de arco son una de las

  14. Analisis Pengaruh Pengalaman Pelanggan (Customer Experience) Terhadap Kepuasan Pelanggan Pada KFC Cabang Walikota

    OpenAIRE

    MAHMUDAH, RIFAATUL

    2011-01-01

    Penelitian ini bertujuan untuk untuk mengetahui dan menganalisis pengaruh pengalaman pelanggan (customer experience) terhadap kepuasan pelanggan pada KFC cabang walikota. Populasi dalam penelitian ini adalah para pelanggan KFC Walikota selama waktu penelitian. Teknik pengambilan sampel menggunakan metode purposive sampling, yaitu metode penentuan sampel dengan pertimbangan tertentu. Peneliti mengambil 138 orang pelanggan sebagai sampel. Metode analisis yang dipergunakan adalah metode anali...

  15. Giant bubble pinch-off

    OpenAIRE

    Bergmann, Raymond; Meer, Van Der; Stijnman, Mark; Sandtke, Marijn; Prosperetti, Andrea; Lohse, Detlef

    2006-01-01

    Self-similarity has been the paradigmatic picture for the pinch-off of a drop. Here we will show through high-speed imaging and boundary integral simulations that the inverse problem, the pinch-off of an air bubble in water, is not self-similar in a strict sense: A disk is quickly pulled through a water surface, leading to a giant, cylindrical void which after collapse creates an upward and a downward jet. Only in the limiting case of large Froude numbers does the purely inertial scaling h(-l...

  16. Power of the pinch: pinch lower lid blepharoplasty.

    Science.gov (United States)

    Kim, Elizabeth M; Bucky, Louis P

    2008-05-01

    Lower lid blepharoplasty is performed with great variation in technique. Conventional lower lid blepharoplasty with anterior fat removal via the orbital septum has a potential lower lid malposition rate of 15% to 20%. Lower lid malposition and the stigma of obvious lower lid surgery have led plastic surgeons to continue to change their approach to lower lid rejuvenation. In recent years, some surgeons have come to rely on alternative procedures like laser resurfacing alone or in conjunction with transconjunctival fat removal and canthopexy in an effort to avoid such complications. The pinch blepharoplasty technique removes redundant skin without undermining. This allows for more controlled wound healing, predictable recovery, and potential for simultaneous laser resurfacing. The combination of pinch blepharoplasty with transconjunctival fat removal leaves the middle lamella intact and reduces the chance of scleral show or ectropion. The purpose of this series is to demonstrate that pinch excision of redundant lower eyelid skin can be safely performed and that it can be used with laser resurfacing and/or transconjunctival fat removal for optimal treatment of the aging eye. A retrospective review of 46 consecutive patients who underwent pinch blepharoplasty, either in isolation or with other periorbital procedures was performed. Follow-up was at least 4 months (range of 4-24 months). In addition, we performed a prospective study of 25 consecutive patients to quantify the amount of skin removed and evaluate results and complications. An average of 8 mm of skin was resected (range of 4-12 mm) with the pinch blepharoplasty technique. Of these patients, 5.6% also underwent transconjunctival blepharoplasty, laser resurfacing, and/or fat grafting of the nasojugal groove. Despite the addition of simultaneous laser resurfacing, we did not see an increase in lower lid malposition. Three of the 71 patients had temporary scleral show that resolved with lower lid massage. In

  17. ANALISIS LITERASI EKONOMI

    Directory of Open Access Journals (Sweden)

    Peter Garlans Sina

    2012-10-01

    Full Text Available Abstract: Analysis of Economic Literacy. The aim of this research is as an effort to increase economic literacy for individuals and households who want to achieve prosperity. Therefore, the obligation of improving the economic literacy needs to be done in a well-planned manner and come from the strong intention to learn in order to improve the economic literacy. It could have an effect on the assets accumulation, a better debt management, as a protection, as well as to increase savings and managing spending intelligently.   Keyword: economic literacy, asset, debt, protection, saving, spending   Abstrak: Analisis Literasi Ekonomi. Tulisan ini bertujuan sebagai upaya meningkatkan literasi ekonomi bagi individu maupun rumah tangga yang menginginkan mencapai kesejahteraan. Oleh karena itu, kewajiban meningkatkan literasi ekonomi perlu dilakukan secara terencana dan diawali dari niat untuk belajar meningkatkan literasi ekonomi karena dapat berefek pada akumulasi aset, pengelolaan utang yang tepat, proteksi, meningkatkan tabungan dan cerdas mengelola pengeluaran.   Kata kunci: literasi ekonomi, aset, utang, proteksi, menabung, pengeluaran

  18. Z-Pinch Fusion for Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    SPIELMAN,RICK B.

    2000-01-01

    Z pinches, the oldest fusion concept, have recently been revisited in light of significant advances in the fields of plasma physics and pulsed power engineering. The possibility exists for z-pinch fusion to play a role in commercial energy applications. We report on work to develop z-pinch fusion concepts, the result of an extensive literature search, and the output for a congressionally-mandated workshop on fusion energy held in Snowmass, Co July 11-23,1999.

  19. Z-Pinch Fusion for Energy Applications

    International Nuclear Information System (INIS)

    Z pinches, the oldest fusion concept, have recently been revisited in light of significant advances in the fields of plasma physics and pulsed power engineering. The possibility exists for z-pinch fusion to play a role in commercial energy applications. We report on work to develop z-pinch fusion concepts, the result of an extensive literature search, and the output for a congressionally-mandated workshop on fusion energy held in Snowmass, Co July 11-23,1999

  20. Giant bubble pinch-off

    CERN Document Server

    Bergmann, R; Prosperetti, A; Sandtke, M; Stijnman, M; Van der Meer, D; Bergmann, Raymond; Lohse, Detlef; Meer, Devaraj van der; Prosperetti, Andrea; Sandtke, Marijn; Stijnman, Mark

    2006-01-01

    Self-similarity has been the paradigmatic picture for the pinch-off of a drop. Here we will show through high-speed imaging and boundary integral simulations that the inverse problem, the pinch-off of an air bubble in water, is not self-similar in a strict sense: A disk is quickly pulled through a water surface, leading to a giant, cylindrical void which after collapse creates an upward and a downward jet. Only in the limiting case of large Froude number the neck radius $h$ scales as $h(-\\log h)^{1/4} \\propto \\tau^{1/2}$, the purely inertial scaling. For any finite Froude number the collapse is slower, and a second length-scale, the curvature of the void, comes into play. Both length-scales are found to exhibit power-law scaling in time, but with different exponents depending on the Froude number, signaling the non-universality of the bubble pinch-off.

  1. Ulnar Nerve Tendon Transfers for Pinch.

    Science.gov (United States)

    Cook, Shane; Gaston, R Glenn; Lourie, Gary M

    2016-08-01

    Power and tip pinch are an integral part of intrinsic hand function that can be significantly compromised with dysfunction of the ulnar nerve. Loss of power pinch is one component that can significantly affect an individual's ability to perform simple daily tasks. Tip pinch is less affected, as this task has significant contributions from the median nerve. To restore power pinch, the primary focus must be on restoring the action of the adductor pollicis primarily, and if indicated the first dorsal interosseous muscle and flexor pollicis brevis. PMID:27387080

  2. Development and validation of single-phase and three-phase transformer models with saturation for the analysis of harmonics in electrical power systems; Desarrollo y validacion de modelos de transformadores monofasicos y trifasicos con saturacion, para el analisis de armonicos en sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Garcia, Ricardo

    2000-11-01

    This work allowed to develop a modeling of the transformer with saturation of the magnetic core focussed to the analysis of flows with harmonics. An experimental study was performed in three laboratories, the laboratory of the Department of Electrical Engineering of the Polytechnic University of Cataluna, and two laboratories of manufacturers of electrical equipment, SALICRV and MIMAVEN. The program of Pspice simulation was used to make the model of the experimental study allowing with it the validation of the developed model against the laboratory tests. [Spanish] Este trabajo permitio desarrollar una modelacion del transformador con saturacion del nucleo magnetico enfocado para el analisis de flujos con armonicos. Se realizo un estudio experimental en tres laboratorios, el laboratorio de el Departamento de Ingenieria Electrica de la Universidad Politecnica de Cataluna, y dos laboratorios de fabricantes de equipos electricos, SALICRV y MIMAVEN. Se utilizo el programa de simulacion Pspice para realizar la modelacion del estudio experimental permitiendo con ello la validacion del modelo desarrollado contra los ensayos de laboratorio.

  3. Analisis Pembentukan Portofolio Saham Optimal Menggunakan Single Index Model Pada Saham-Saham Perbankan Yang Terdaftar Di Bursa Efek Indonesia

    OpenAIRE

    Nanci, Okri

    2015-01-01

    Untuk meminimalkan risiko, investor perlu melakukan portofolio optimal agar risiko dapat disebarkan. Pemilihan portofolio yang optimal sangat tergantung pada analisis ketepatan ketepatan para investor dalam mencermati dan menganalisis pasar. Tujuan penelitian adalah untuk membentuk portofolio optimal dan mengetahui perbedaan return dan risiko antara saham kandidat dan non kandidat portofolio. Penelitian ini dilakukan menggunakan model indeks tunggal, dan data yang digunakan adalah harga p...

  4. ANALISIS PENILAIAN PRESTASI KERJA PEGAWAI

    Directory of Open Access Journals (Sweden)

    Puspita Rokhmawati

    2013-03-01

    Full Text Available Tujuan analisis ini untuk mengetahui sistem, evaluasi dan perubahan penilaian prestasi kerja pegawai UPT Balai Konservasi Tumbuhan Kebun Raya Cibodas -LIPI. Pengambilan sampel dalam penelitian ini dilakukan secara acak dengan metode yang digunakan terdiri dari beberapa bagian, yaitu studi pustaka, studi lapangan dan metode analisis. Metode yang digunakan adalah Metode Analisis SWOT. Hasil analisis menunjukkan banyak kelemahan yang muncul daripada kekuatan yang dimiliki. Peluang dan ancaman yang ada pun tidak memotivasi dalam mengimplementasi ke sistem penilaian prestasi kerja. Oleh karena itu perlu upaya mengevaluasi dan mengubah sistem penilaian prestasi kerja pegawai. Pemberian umpan balik akan mendorong kearah kemajuan dan kemungkinan meningkatkan kualitas kerja pegawai. Maka penilaian harus dibuat seobjektif dan seteliti mungkin berdasarkan data yang tersedia.The purpose of this study is  to determine the system, the  evaluation and the assessment of employees’ job performance in UPT Botanical Gardens Plant Conservation Center Cibodas - LIPI. UPT Botanical Gardens Plant Conservation Center Cibodas - LIPI has not carry out  an optimal job performance assessment. There are indications that the condition relate to the presence of subjectivity in the assessment so depth analysis is needed to find out the solution. Sampling technique uses random sampling. SWOT analysis is used to analyze the data along with study of literature and field study. The result shows that more weaknesses reveale in job performance assessment system than strengths.Opportunities and treats are ignored in implementing the job performance assessment system. Evaluation and modification are needed to improve employees’ job quality.

  5. Lower pinch radius limit in EXTRAP

    International Nuclear Information System (INIS)

    In an Extrap pinch there is a superimposed magnetic octupole field which forms a magnetic separatrix with the field generated by the pinch current. Earlier experiments have shown that the octupole field has a stabilizing influence on the plasma. Regardless of the details of this stabilizing mechanism, it is expected that the influence of the octupole field should become negligible for a sufficiently small ratio between the characteristic pinch and separatrix radii. In other words, there should exist a lower limit of this ratio below which the system approaches the state of an ordinary unstabilized Z-pinch. The present paper presents an extended version of an earlier theoretical model of this lower limit, and its relation to the corresponding critical ratio between the external conductor and pinch currents. This ratio is found to vary substantially with the plasma parameters. (authors)

  6. Autocatalytic plume pinch-off

    CERN Document Server

    Rogers, Michael C; Morris, Stephen W

    2010-01-01

    A localized source of buoyancy flux in a non-reactive fluid medium creates a plume. The flux can be provided by either heat, a compositional difference between the fluid comprising the plume and its surroundings, or a combination of both. For autocatalytic plumes produced by the iodate-arsenous acid reaction, however, buoyancy is produced along the entire reacting interface between the plume and its surroundings. Buoyancy production at the moving interface drives fluid motion, which in turn generates flow that advects the reaction front. As a consequence of this interplay between fluid flow and chemical reaction, autocatalytic plumes exhibit a rich dynamics during their ascent through the reactant medium. One of the more interesting dynamical features is the production of an accelerating vortical plume head that in certain cases pinches-off and detaches from the upwelling conduit. After pinch-off, a new plume head forms in the conduit below, and this can lead to multiple generations of plume heads for a singl...

  7. Upper pinch radius limit in EXTRAP

    International Nuclear Information System (INIS)

    A simple static equilibrium model of the Z-pinch is considered where a hot plasma core is surrounded by a cold-mantle (gas blanket). The pinch radius, defined as the radial extension of the fully ionized plasma core, is uniquely determined by the plasma particle. momentum and heat balance equations. In Extrap configurations an octupole field is introduced which imposes a magnetic separatrix on Z-pinch geometry. This makes the conditions for Extrap equilibrium 'overdetermined' when the characteristic pinch radium given by the plasma parameters tends to exceed the characteristic radius of the magnetic separatrix. In this case no conventional pinch equilibrium can exist, and part of the current which is forced into the plasma discharge by external sources must be channelled outside of the separatrix, i.e. into the surrounding support structure of the Extrap conductors and the vessel walls. A possibly existing bootstrap current in the plasma boundary layer is further expected to be 'scraped off' in this case. The present paper gives some illustrations of the marginal case of this upper pinch radius limit, in a state where the pinch current is antiparallel to the external rod currents which generate the octupole field. (authors)

  8. Investigation of table top X-pinches

    International Nuclear Information System (INIS)

    The X-pinch is created by passing a large current through two or more wires crossed and touching at a single point. The X-pinch has been found to be an excellent source of high intensity, short duration X-rays, which has led to a wide range of applications in areas such as lithography, radiography, biomedicine, and materials science. An investigation was carried out relating to how the characteristics of the X-rays emissions and plasma dynamics of X-pinches change with the number of wires utilized. The pinches were created by passing a 58 ns, 38 kA current pulse through tungsten wires. Wire configurations using 2,3,4, and 6 wires were used. The main diagnostic tools consisted of a CCD camera for time-integrated optical images, a pinhole camera to record time-integrated images of the X-ray emissions and X-ray diodes to determine the pinch time. X-pinches with a greater number of wires were found to result in an increase in size and intensity of the vertical plasma jets, as well as an increase in the time taken before the pinch would occur.

  9. Nitrogen laser system for diagnosing z-pinch and x-pinch plasmas

    International Nuclear Information System (INIS)

    A nitrogen laser system built to probe dense z-pinch and x-pinch plasmas is described. This low-cost system consists of an atmospheric pressure oscillator and a low pressure amplifier. It generates a 1-cm-diam 3371 Angstrom laser beam with approximately 0.33 mJ in a approx-lt 1 ns pulse, and with a coherence length of at least 5 cm. This laser has been used in several modes of operation, such as for simultaneous schlieren and interferometry imaging of dense z-pinch and x-pinch plasmas. Example results are presented. copyright 1997 American Institute of Physics

  10. Analisis sobre las obligaciones

    OpenAIRE

    Parra Avila, Elliot

    2013-01-01

    Los lenguajes ordinarios presentan dificultades de interpretación cuando son usados para formular y resolver problemas filosoficos. Estos inconvenientes intentaron ser solucionados desde las funciones propositivas (Russell) y los lenguajes artificiales (Carnap). Como respuesta a estas tesis surge la escuela de la filosofia del lenguaje ordinario que sostiene 1) la confianza en el lenguaje claro y siple 2) la ideificacion del abuso del lenguaje como origen de todos los problemas filosoficos 3)...

  11. Pinch analysis of evaporation systems

    Directory of Open Access Journals (Sweden)

    Westphalen D.L.

    2000-01-01

    Full Text Available Evaporation systems are separation processes widely used in chemical industries. Some guidelines can be found in the literature for the process integration of multiple effect evaporators. In the published methodologies some aspects are neglected as boiling point rise, effect of pressure on latent heat of water, sensible heat of liquid streams, heat of mixing, effects configuration and inclusion of accessories. In this work, a new graphical representation for the integration of multiple effect evaporators was developed, using rigorous physical properties. From this representation, an algorithm for optimization of bleed streams was conceived using the concepts of Pinch Analysis. As a case study, a crystal glucose plant was optimized using this new methodology. The optimization of bleed streams showed as result a steam consumption 16% smaller than a similar previous study. From energy and capital costs, it is shown that the integrated evaporator exhibits a total cost 14% smaller than the non-integrated configuration.

  12. Separation enhancement in pinched flow fractionation

    DEFF Research Database (Denmark)

    Vig, Asger Laurberg; Kristensen, Anders

    2008-01-01

    A method for enhancing the separation in the microfluidic size separation technique called pinched flow fractionation (PFF) is demonstrated experimentally and analyzed by numerical calculations. The enhancement is caused by a geometrical modification of the original PFF design. Seven different...

  13. Analisi SWOT Terhadap Manajemen Rumah Sakit

    OpenAIRE

    Rahmati MR

    2008-01-01

    SWOT adalah singkatan dari strengths dan weaknesses serta opportunities dan threats. Analisis SWOT merupakan suatu kajian terhadap kekuatan dan kelemahan internal sebuah organisasi serta kesempatan dan ancaman lingkungan eksternalnya. Teknik analisis SWOT yang digunakan adalah mathematics of SWOT yaitu dengan menggunakan rumus (S-W) + (0—T), jika hasil yang diperoleh plus maka strateginya adalah menguatkan S dan O, jika equal maka strateginya adalah mengurangi W dan T9 dan jika minus maka ...

  14. Superfast Z-pinch-produced plasmas

    International Nuclear Information System (INIS)

    The superfast z-pinch has been investigated as a possible means of producing an ultra-high (approx. 100 keV) temperature plasma. An ion Vlasov fluid electron code is shown to simulate the experimental behavior of a pinch. Dependence of the temperature on wall generated impurity, initial density profile, and generator parameters are indicated. Extrapolation of the code using state of the art pulse generators indicate feasibility of an ultra-high temperature plasma

  15. The Physics of Fast Z Pinches

    Energy Technology Data Exchange (ETDEWEB)

    RYUTOV,D.D.; DERZON,MARK S.; MATZEN,M. KEITH

    1999-10-25

    The spectacular progress made during the last few years in reaching high energy densities in fast implosions of annular current sheaths (fast Z pinches) opens new possibilities for a broad spectrum of experiments, from x-ray generation to controlled thermonuclear fusion and astrophysics. Presently Z pinches are the most intense laboratory X ray sources (1.8 MJ in 5 ns from a volume 2 mm in diameter and 2 cm tall). Powers in excess of 200 TW have been obtained. This warrants summarizing the present knowledge of physics that governs the behavior of radiating current-carrying plasma in fast Z pinches. This survey covers essentially all aspects of the physics of fast Z pinches: initiation, instabilities of the early stage, magnetic Rayleigh-Taylor instability in the implosion phase, formation of a transient quasi-equilibrium near the stagnation point, and rebound. Considerable attention is paid to the analysis of hydrodynamic instabilities governing the implosion symmetry. Possible ways of mitigating these instabilities are discussed. Non-magnetohydrodynamic effects (anomalous resistivity, generation of particle beams, etc.) are summarized. Various applications of fast Z pinches are briefly described. Scaling laws governing development of more powerful Z pinches are presented. The survey contains 36 figures and more than 300 references.

  16. The physics of fast Z pinches

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D.D. [Lawrence Livermore National Lab., CA (United States); Derzon, M.S.; Matzen, M.K. [Sandia National Labs., Albuquerque, NM (United States)

    1998-07-01

    The spectacular progress made during the last few years in reaching high energy densities in fast implosions of annular current sheaths (fast Z pinches) opens new possibilities for a broad spectrum of experiments, from x-ray generation to controlled thermonuclear fusion and astrophysics. Presently Z pinches are the most intense laboratory X ray sources (1.8 MJ in 5 ns from a volume 2 mm in diameter and 2 cm tall). Powers in excess of 200 TW have been obtained. This warrants summarizes the present knowledge of physics that governs the behavior of radiating current-carrying plasma in fast Z-pinches. This survey covers essentially all aspects of the physics of fast Z pinches: initiation, instabilities of the early stage, magnetic Rayleigh-Taylor instability in the implosion phase, formation of a transient quasi-equilibrium near the stagnation point, and rebound. Considerable attention is paid to the analysis of hydrodynamic instabilities governing the implosion symmetry. Possible ways of mitigating these instabilities are discussed. Non-magnetohydrodynamic effects (anomalous resistivity, generation of particle beams, etc.) are summarized. Various applications of fast Z pinches are briefly described. Scaling laws governing development of more powerful Z pinches are presented. The survey contains 52 figures and nearly 300 references.

  17. The physics of fast Z pinches

    International Nuclear Information System (INIS)

    The spectacular progress made during the last few years in reaching high energy densities in fast implosions of annular current sheaths (fast Z pinches) opens new possibilities for a broad spectrum of experiments, from x-ray generation to controlled thermonuclear fusion and astrophysics. Presently Z pinches are the most intense laboratory X ray sources (1.8 MJ in 5 ns from a volume 2 mm in diameter and 2 cm tall). Powers in excess of 200 TW have been obtained. This warrants summarizes the present knowledge of physics that governs the behavior of radiating current-carrying plasma in fast Z-pinches. This survey covers essentially all aspects of the physics of fast Z pinches: initiation, instabilities of the early stage, magnetic Rayleigh-Taylor instability in the implosion phase, formation of a transient quasi-equilibrium near the stagnation point, and rebound. Considerable attention is paid to the analysis of hydrodynamic instabilities governing the implosion symmetry. Possible ways of mitigating these instabilities are discussed. Non-magnetohydrodynamic effects (anomalous resistivity, generation of particle beams, etc.) are summarized. Various applications of fast Z pinches are briefly described. Scaling laws governing development of more powerful Z pinches are presented. The survey contains 52 figures and nearly 300 references

  18. Analisis Kebijakan dan Efektivitas Organisasi

    Directory of Open Access Journals (Sweden)

    Amir Syarifudin Kiwang

    2015-05-01

    Full Text Available Penerapan Peraturan Gubernur Nusa Tenggara Timur Nomor 8 Tahun 2011 tentang Organisasi dan Tata Kerja Unit Pelaksana Teknis Pendidikan dan Pelatihan Koperasi dan Usaha Mikro Kecil dan Menengah pada Dinas Koperasi dan Usaha Mikro Kecil dan Menengah Provinsi Nusa Tenggara Timur adalah dalam rangka untuk meningkatkan efektivitas kerja organisasi pada UPT Diklat Koperasi dan UMKM. Penelitian ini berusaha untuk melihat dampak kebijakan organisasi terhadap efektivitas organisasi dengan menggunakan enam elemen variabel dari kebijakan dan praktik manajemen. Keenam elemen tersebut adalah penetapan tujuan strategis, pencarian dan pemanfaatan sumber daya, lingkungan prestasi, proses komunikasi, kepemimpinan dan pengambilan keputusan, serta adaptasi dan inovasi organisasi. Penelitian kualitatif ini menggunakan pendekatan studi kasus. Teknik analisis data yang digunakan adalah analisis data model Miles dan Huberman, yang terdiri atas reduksi data, display/penyajian data, dan kesimpulan/verifikasi. Hasil penelitian menunjukkan bahwa efektivitas organisasi pada UPT Diklat koperasi dan UMKM belum berjalan secara baik, hal ini dapat dilihat dari beberapa hal antara lain, belum adanya tenaga spesialisasi pengelola diklat dan tenaga khusus (sarjana di bidang perkoperasian dan kondisi lingkungan kerja (lingkungan prestasi pada UPT Diklat koperasi dan UMKM yang belum efektif. Penempatan pegawai juga belum tepat, mutasi ke UPT Diklat Koperasi dan UMKM tidak memperhatikan latar belakang pendidikan dan spesialisasi/keahlian pegawai sehingga membutuhkan waktu dalam proses penyesuaian serta menurunkan jumlah pelaksanaan diklat dikarenakan keterbatasan alokasi dana.

  19. Risk analysis in the chemical industry; Analisis de riesgos en la industria quimica

    Energy Technology Data Exchange (ETDEWEB)

    Rea Soto, Rogelio; Sandoval Valenzuela, Salvador [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2000-07-01

    The Instituto de Investigaciones Electricas has a group of risk analysis (GAR), specialized in the most advanced methodologies to apply them in diverse industries of the productive sector, such as the nuclear, the oil and the chemical industries. In this work the integrated methodology that the GAR uses to make risk analysis in the chemical and oil industries is described. These analyses have as an objective to make a meticulous evaluation of the system design, the operation practices, the maintenance and inspection policies and the emergency plans. [Spanish] El Instituto de Investigaciones Electricas cuenta con un grupo de analisis de riesgo (GAR), especializado en las metodologias mas avanzadas para aplicarlas en diversas industrias del sector productivo, como lo son la nuclear, la petrolera y la quimica. En este trabajo se describe la metodologia integrada que el GAR utiliza para realizar analisis de riesgos en las industrias quimica y petrolera. Estos analisis tienen como objetivo realizar una minuciosa evaluacion del diseno del sistema, las practicas de operacion, las politicas de mantenimiento e inspeccion y los planes de emergencia.

  20. Development Path for Z-Pinch IFE

    International Nuclear Information System (INIS)

    The long-range goal of the Z-Pinch IFE program is to produce an economically-attractive power plant using high-yield z-pinch-driven targets (∼3GJ) with low rep-rate per chamber (∼0.1 Hz). The present mainline choice for a Z-Pinch IFE power plant uses an LTD (Linear Transformer Driver) repetitive pulsed power driver, a Recyclable Transmission Line (RTL), a dynamic hohlraum z-pinch-driven target, and a thick-liquid wall chamber. The RTL connects the pulsed power driver directly to the z-pinch-driven target, and is made from frozen coolant or a material that is easily separable from the coolant (such as carbon steel). The RTL is destroyed by the fusion explosion, but the RTL materials are recycled, and a new RTL is inserted on each shot.A development path for Z-Pinch IFE has been created that complements and leverages the NNSA DP ICF program. Funding by a U.S. Congressional initiative of $4M for FY04 through NNSA DP is supporting assessment and initial research on (1) RTLs, (2) repetitive pulsed power drivers, (3) shock mitigation [because of the high yield targets], (4) planning for a proof-of-principle full RTL cycle demonstration [with a 1 MA, 1 MV, 100 ns, 0.1 Hz driver], (5) IFE target studies for multi-GJ yield targets, and (6) z-pinch IFE power plant engineering and technology development. Initial results from all areas of this research are discussed

  1. Anomalous particle pinch in Tokamaks

    International Nuclear Information System (INIS)

    The diffusion coefficient in phase space usually varies with the particle energy. A consequence is the dependence of the fluid particle flux on the temperature gradient. If the diffusion coefficient in phase space decreases with the energy in the bulk of the thermal distribution function, the particle thermodiffusion coefficient which links the particle flux to the temperature gradient is negative. This is a possible explanation for the inward particle pinch that is observed in tokamaks. A quasilinear theory shows that such a thermodiffusion is generic for a tokamak electrostatic turbulence at low frequency. This effect adds to the particle flux associated with the radial gradient of magnetic field. This behavior is illustrated with a perturbed electric potential, for which the trajectories of charged particle guiding centers are calculated. The diffusion coefficient of particles is computed and compared to the quasilinear theory, which predicts a divergence at low velocity. It is shown that at low velocity, the actual diffusion coefficient increases, but remains lower than the quasilinear value. Nevertheless, this differential diffusion between cold and fast particles leads to an inward flux of particles. (author)

  2. Hot spots in fiber pinches

    International Nuclear Information System (INIS)

    Results are presented on the behavior of ''bright spots'' in carbon and deuterium fiber Z-pinches using the MAGPIE generator at the I MA current level. The experimental diagnosis was carried out using optical and X-ray framing and streak images, along with Schlieren and shadowgraphy laser probing. After a short (∼4 ns) duration formation phase, these bright spots exhibit highly dynamic behavior. Bifurcation of the bright spots gives rise to rapid axial motion at 1-3x105 m/sec. The post-bifurcation bright spots persist for up to 40 ns. The important features of bright spot evolution can be reproduced using a 2-D MHD code incorporating LTE ionization dynamics and cold start conditions. Construction of ''artificial'' diagnostic images from the simulation data allows direct comparison to experiment. From the close agreement between experiment and 2-D simulation we infer that the observed bright spot behavior can be explained entirely in terms of the non-linear evolution of the m=0 instability

  3. The use of multivariate analysis to link sediment contamination and toxicity data to establish sediment quality guidelines: an example in the Gulf of Cadiz (Spain); El uso del analisis multivariante en la union de datos de toxicidad y contaminacion para establecer guias de calidad de sedimento: Un ejemplo en la Bahia de Cadiz (Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Del Valls, T. Angel; Forja, Jesus M [Departamento de Quimica Fisica, Facultad de Ciencias del Mar, Universidad de Cadiz, Cadiz, (Spain); Gomez-Parra, Abelardo [Instituto de Ciencias Marinas de Andalucia, CSIC, Puerto Real, Cadiz, (Spain)

    1998-03-01

    which biological effects have been shown to be minimal (mg kg{sup -}1 dry sediment), are: Hg, 0.25; Ag, 0.78; Pb, 66.80; Cr, 101.2; LAS, 2.6. [Spanish] Para evaluar la calidad de los sedimentos marinos en el Golfo de Cadiz, los datos provenientes de concentraciones quimicas y respuestas de toxicidad en sedimentos fueron unidos usando el analisis ultivariante. Las muestras de sedimentos fueron recogidas sinopticamente en siete estaciones de dos ecosistemas litorales en el Golfo de Cadiz (cinco en la Bahia de Cadiz y dos en las marismas del rio Barbate) y fueron sujetas a seis tests de toxicidad de forma independiente y replicada, asi como a analisis quimicos. Los efectos toxicos en los sedimentos se chequearon utilizando tres fases operativas del sedimento: sedimento bruto, utilizando el anfipodo Microdeutopus gryllotalpa (10 d estatico: supervivencia) y la almeja de estuario Ruditapes philippinarum (48 h estatico: enterramiento); extracto de sedimento, utilizando larvas del bivalvo de estuario Crassostrea angulata (48 h estatico: supervivencia) y del pez marino Sparus aurata (48 h estatico: supervivencia); y agua intersticial, utilizando poblaciones del rotifero de estuario Brachionus plicatilis (7 d estatico: decaimiento de la poblacion) y de la bacteria marina Photobacterium phosphoreum (Microtox ). Para evaluar los niveles de contaminacion se determinaron las concentraciones en los sedimentos de carbono organico, 14 metales traza (Fe, Mn, Cu, Zn, Pb, Cd, Ag, Hg, As, Sn, V, Ni, Co y Cr) y el detergente alquibencenosulfonato lineal (LAS). Los resultados de los ensayos de toxicidad se compararon mediante relaciones de respuesta entre las diferentes estaciones, demostrando una concordancia general entre los valores de toxicidad determinados en todos los tests, excepto en el caso de la toxicidad en el agua intersticial (principalmente debido a mezclas de metales traza toxicas). Los datos obtenidos en los ensayos quimicos y de toxicidad se ensamblaron utilizando tecnicas

  4. Radiative signatures of Z-pinch plasmas at UNR: from X-pinches to wire arrays

    International Nuclear Information System (INIS)

    University-scale Z-pinch generators are able to produce High Energy Density (HED) plasmas in a broad range of plasma parameters under well-controlled and monitored experimental conditions suitable for radiation studies. The implosion of X-pinch and wire array loads at a 1 MA generator yields short (1-20 nsec) x-ray bursts from one or several bright plasma spots near the wire cross point (for X-pinches) or along and near Z-pinch axis (for wire arrays). Such X- and Z-pinch HED plasma with scales from a few µm to several mm in size emits radiation in a broad range of energies from 10 eV to 0.5 MeV and is subject of our studies during the last ten years. In particular, the substantial number of experiments with very different wire loads was performed on the 1 MA Zebra generator and analyzed: X-pinch, cylindrical, nested, and various types of the novel load, Planar Wire Arrays (PWA). Also, the experiments at an enhanced current of 1.5-1.7 MA on Zebra using Load Current Multiplier (LCM) were performed. This paper highlights radiative signatures of X-pinches and Single and Double PWAs which are illustrated using the new results with combined wire loads from two different materials. (author)

  5. Axial x-ray backlighting of wire-array Z-pinches using X pinches

    International Nuclear Information System (INIS)

    For the first time, a geometry has been developed to allow for an axial imaging system for wire-array Z-pinch experiments that produce high-resolution x-ray images. The new geometry required a significant redesign of the electrode hardware. Calibrated areal density measurements of the Z-pinch plasma including wire cores, coronal plasma, streaming plasma, and the precursor were obtained. The system used eight-wire molybdenum (Mo) X pinches in series with and directly below the Z-pinch axis to provide micron-scale x-rays sources for point-projection radiography. The images formed on the x-ray sensitive film had a 15 mm diameter field of view at the center height of the array and a magnification of about 7.5:1. Titanium (Ti) filters in front of the film transmitted radiation in the spectral range of 3-5 keV. For calibration, a separate film with the same thickness Ti filter was placed the same distance from the X pinch. This film had an unobstructed path that bypasses the Z-pinch but included step wedges for calibration of the Z-pinch plasma. The step wedges had thicknesses of tungsten (W) ranging from 0.015 to 1.1 μm to obtain areal density measurements of the W plasma from the wire-array. Images had subnanosecond temporal resolution and about 10 μm spatial resolution.

  6. Axial x-ray backlighting of wire-array Z-pinches using X pinches

    Science.gov (United States)

    Blesener, I. C.; Greenly, J. B.; Pikuz, S. A.; Shelkovenko, T. A.; Vishniakou, S.; Hammer, D. A.; Kusse, B. R.

    2009-12-01

    For the first time, a geometry has been developed to allow for an axial imaging system for wire-array Z-pinch experiments that produce high-resolution x-ray images. The new geometry required a significant redesign of the electrode hardware. Calibrated areal density measurements of the Z-pinch plasma including wire cores, coronal plasma, streaming plasma, and the precursor were obtained. The system used eight-wire molybdenum (Mo) X pinches in series with and directly below the Z-pinch axis to provide micron-scale x-rays sources for point-projection radiography. The images formed on the x-ray sensitive film had a 15 mm diameter field of view at the center height of the array and a magnification of about 7.5:1. Titanium (Ti) filters in front of the film transmitted radiation in the spectral range of 3-5 keV. For calibration, a separate film with the same thickness Ti filter was placed the same distance from the X pinch. This film had an unobstructed path that bypasses the Z-pinch but included step wedges for calibration of the Z-pinch plasma. The step wedges had thicknesses of tungsten (W) ranging from 0.015 to 1.1 μm to obtain areal density measurements of the W plasma from the wire-array. Images had subnanosecond temporal resolution and about 10 μm spatial resolution.

  7. Plasma focus - dense Z pinch and their applications

    International Nuclear Information System (INIS)

    ''Workshop on the possibility of Z-pinch as a intense pulse light source'' in 1983 and ''Research meeting on plasma focus and Z-pinch'' in 1984 were held at Institute of Plasma Physics, Nagoya University under a collaborating research program. Research activities reported at the meetings on plasma focus, dense Z-pinch, and related phenomena are summerized. (author)

  8. High-density Z-pinch research

    International Nuclear Information System (INIS)

    The linear Z pinch is a plasma configuration which in its simplest form requires no auxiliary magnetic field; an axial current carried by the plasma produces an azimuthal confining field and provides ohmic (resistive) or implosion heating. The Lawson criterion (n tau > 1020 m-3s) and high temperatures (T > 10 keV) must be simultaneously satisfied in any reactor scheme. Early Z-pinch experiments concentrated on the sub-atmospheric fill pressure regime, with 1019 m-3 23 m-3 and a corresponding confinement time constraint of 101 s > tau > 10-4 s. In addition, these studies involved plasmas formed at the surface of an insulating wall; the plasmas were subsequently pinched inward by the radial j x B force. Following the implosion phase, gross MHD instabilities were invariably observed on a time scale short compared to the required confinement time

  9. Gas-puff Z-pinch experiment

    International Nuclear Information System (INIS)

    The fast linear Z-pinch was experimentally investigatedusing a pulse high-current generator (10.8 μF, 5 to 10 kJ. 150 to 250 kA) and a pulse injectionof argon and neon. Measured electrical characteristics of the discharge (current shape and risetime, inductance) and calculated dynamic parameters of plasma implosion (accelerated mass, radial plasma velocity) are presented. X-ray diagnostics with temporal resolution (vacuum X-ray diodes, semiconductor detectors) were utilized. The temperature and the density of pinch plasma (Te ≅ 50 eV, ne ≅ 1.4x1026 m-3) and its size and lifetime were estimated. Total energy emitted by pinch in ultra-soft X-ray region (hν<1 keV) during ∼ 200 ns pulse achieves 125 J/4π. (author). 5 figs., 1 tab., 16 refs

  10. PROTOCOLOS DE CONTROL DE DISPOSITIVOS DOMOTICOS: ANALISIS DE PATENTESPROTOCOLO DE COMUNICACIÓN PARA SISTEMAS INALÁMBRICOS DE BUS DE REPETICIÓN EN EQUIPOS DE MEDICIÓN

    Directory of Open Access Journals (Sweden)

    Paz Silmer E.

    2006-07-01

    Full Text Available La presente investigación plantea el diseño de un protocolo de comunicación, para sistemas inalámbricos, específicamente de radiofrecuencia con lo cual todos los nodos en la red puedan recibir la información enviada desde cualquier otro dentro de su alcance, esta habilidad permite que cada uno pueda servir de repetidor para alcanzar nodos fuera del radio de acción del emisor, estableciendo el tipo de red como bus de repetición. Las características y propiedades de la red conllevan una serie de inconvenientes, entre los cuales tenemos la saturación de la red, altas probabilidades de error, posibles pérdidas de paquetes, entre otros. Dichas debilidades se atacan en este diseño para el uso eficiente de la infraestructura planteada. La investigación se catalogó como descriptiva bajo la modalidad de campo, con un diseño no experimental. La metodología utilizada es propia del autor contemplando 4 fases basadas en el modelo referencial OSI para el diseño de protocolos. Como resultado se obtuvo la selección de algoritmos y técnicas óptimas para el establecimiento de comunicación de sistemas inalámbricos de este tipo, se muestra la comparación de los algoritmos de Reed-Solomon y Viterbi para corrección de errores. También se presentan el diseño del modelo de direccionamiento, estructura de paquetes y el algoritmo de balanceo de carga y enrutamiento basado en el camino más corto de Bellman para grafos.

  11. Dense Z-pinches by carbon fiber pinch and by conductive thin film linear compression

    International Nuclear Information System (INIS)

    Dense Z-pinch plasmas are created by two different ways and are examined experimentally. A stable plasma column existing for about 20 ns has been created in the carbon fiber pinch driven by a pulsed power generator. Any significant differences in emitted soft X-ray intensity from the plasma are not observed between fiber pinches of carbon fiber with nickel or copper coating and without any coating material. Techninal difficulties in handling thin foil metal liner for linear compression experiments are overcome by proposing a conductive thin film deposited on the surface of discharge tube wall as a compression liner. Uniform cyclindrical compression of the thin film liner has been confirmed

  12. Wave dynamics of theta pinch implosions

    International Nuclear Information System (INIS)

    A model based on two constraints is proposed for theta pinch implosions. The first constraint states that the external radial force per mass density is the same for both electron and ion fluids like in a newtonian system. The second constraint is the quasi-neutrality. In cylindrical geometry, this model claims different radial velocities for the two fluids, plasma rotation in the azimuthal direction, and a minimum two dimensional consistent description. The physics of electron beam current saturation is shown to be very relevant in reverse biased pinches. (author)

  13. Fusion in a staged Z-pinch

    Science.gov (United States)

    Wessel, F. J.; Rahman, H. U.; Ney, P.; Valenzuela, J.; Beg, F.; McKee, E.; Darling, T.

    2016-03-01

    This paper is dedicated to Norman Rostoker, our (FJW and HUR) mentor and long-term collaborator, who will always be remembered for the incredible inspiration that he has provided us. Norman's illustrious career dealt with a broad range of fundamental-physics problems and we were fortunate to have worked with him on many important topics: intense-charged-particle beams, field-reversed configurations, and Z-pinches. Rostoker 's group at the University of CA, Irvine was well known for having implemented many refinements to the Z-pinch, that make it more stable, scalable, and efficient, including the development of: the gas-puff Z-pinch [1], which provides for the use of an expanded range of pinch-load materials; the gas-mixture Z-pinch [2], which enhances the pinch stability and increases its radiation efficiency; e-beam pre-ionization [3], which enhances the uniformity of the initial-breakdown process in a gas pinch; magnetic-flux-compression [4, 5], which allows for the amplification of an axial-magnetic field Bz; the Z-θ pinch [6], which predicts fusion in a pinch-on-fiber configuration; the Staged Z-pinch (SZP) [7], which allows for the amplification of the pinch self-magnetic field, Bθ , in addition to a Bz, and leads to a stable implosion and high-gain fusion [8, 9, 10]. This paper describes the physical basis for a magneto-inertial compression in a liner-on-target SZP [11]. Initially a high-atomic-number liner implodes under the action of the J →×B → , Lorentz Force. As the implosion becomes super Alfvénic, magnetosonic waves form, transporting current and magnetic field through the liner toward the interface of the low-atomic-number target. The target implosion remains subsonic with its surface bounded by a stable-shock front. Shock waves that pass into the target provide a source of target plasma pre-heat. At peak compression the assembly is compressed by liner inertia, with flux compression producing an intense-magnetic field near the target

  14. Pinch-off of rods by bulk diffusion

    DEFF Research Database (Denmark)

    Aagesen, L.K.; Johnson, A.E.; Fife, J.L.;

    2011-01-01

    pinching. The theory is compared to experiments that employ in situ four-dimensional X-ray tomographic microscopy for rods of liquid or solid pinching by solute diffusion in the high-diffusivity liquid phase. The excellent agreement between experiment and theory confirms that the interfacial morphology......The morphology of a rod embedded in a matrix undergoing pinching by interfacial-energy-driven bulk diffusion is determined near the point of pinching. We find a self-similar solution that gives a unique temporal power law and interfacial shape prior to pinching and self-similar solutions after...

  15. Hybrid simulations of Z-pinches

    Czech Academy of Sciences Publication Activity Database

    Sotnikov, V. I.; Bauer, B. S.; LeBoeuf, J. N.; Hellinger, Petr; Trávníček, Pavel; Fiala, Vladimír

    2004-01-01

    Roč. 164, č. 1-3 (2004), s. 150-155. ISSN 0010-4655 R&D Projects: GA AV ČR IAB3042106 Institutional research plan: CEZ:AV0Z3042911 Keywords : Z-pinch * Instability * Hall term * Kinetic ions Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.515, year: 2004

  16. Bootstrap states of the Z-pinch

    International Nuclear Information System (INIS)

    Steady bootstrap states of a Z-pinch are investigated both in absence and in presence of an imposed axial magnetic field, in terms of MHD theory with classical resistivity. The results indicate that bootstrap operation should become possible for certain classes of plasma profiles and that such operation can lead to higher bootstrap currents in a Z-pinch without axial magnetic field than in a tokamak-like case under similar plasma conditions. The ratio between the latter and the former currents is of the order of the square root of the beta value in the tokamak-like case. A simple numerical example is given on boot-strap operation in the Z-pinch. Neoclassical or anomalous diffusion will increase the diffusion velocity of the plasma but are not expected to affect the main physical features of the present results. This applies also to the kinetic effects in the weak-field region near the axis of the Z-pinch, because these effects can largely be described by MHD-like equations for a steady equilibrium. Bootstrap operation and the technical difficulty in realizing a volume distribution of particle sinks introduce certain constraints on the plasma and current profiles. This has to be taken into account in a stability analysis. The latter cannot only be performed in terms of MHD-like theory but has to be based on kinetic theory including large Larmor radius (LLR) effects. (author)

  17. Dynamics of hybrid X-pinches

    Energy Technology Data Exchange (ETDEWEB)

    Shelkovenko, T. A.; Tilikin, I. N.; Ivanenkov, G. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Stepniewski, W. [Institute of Plasma Physics and Laser Microfusion (Poland); Mingaleev, A. R.; Romanova, V. M.; Agafonov, A. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Cahill, A. D.; Hoyt, C. L.; Gourdain, P. A.; Hammer, D. A. [Cornell University (United States); Pikuz, S. A., E-mail: pikuz@mail.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2015-01-15

    The dynamics of a new type of pinches—hybrid X-pinches (HXPs)—has been studied experimentally and numerically. The initial configuration of an HXP consists of a high-current diode with conical tungsten electrodes separated by a 1- to 3-mm-long gap and shunted with a 20- to 100-μm diameter wire. It was shown earlier that a hot spot (HS) with high plasma parameters also formed in the HXP, although its initial configuration is simpler than that of a standard X-pinch. Although details of the HXP dynamics still remain insufficiently studied, the main factors governing the HXP formation were investigated both experimentally and using magnetohydrodynamic simulations. The formation of a specific pressure profile in the electrode plasma after the wire explosion was investigated both experimentally and theoretically. It is shown that the effect of the pressure profile on the expanding wire plasma is similar for both standard X-pinches and HXPs, which allows one to assign them to the same class of loads of pulsed facilities. It is also established that the final stages of HS formation and the parameters of the HS plasma in standard X-pinches and HXPs are practically identical.

  18. Scylla IV-P theta pinch

    International Nuclear Information System (INIS)

    Scylla IV-P is a flexible, linear theta pinch designed to investigate high-density linear concepts, end-stoppering, alternate heating methods, and plasma injection techniques relevant to a pure fusion reactor and/or a fusion-fission hybrid system. The construction and experimental arrangement of the device are briefly described

  19. Pinched Flow Fractionation – Teknologi and Applikation

    DEFF Research Database (Denmark)

    Vig, Asger Laurberg

    biologiske og kemiske systemer, er en mikrofluid størrelsessorteringsteknik ved navn pinched flow fractionation (PFF) valgt som modelsystem. En høj-volumen fabrikations teknik, baseret på rulleaftryk til polymer-baseret LOC komponenter, er udviklet og demonstreret ved fabrikation af funktionsdygtige PFF...

  20. Cadenas de Markov, evaluacion multicriterio y evaluacion multiobjetivo para la modelizacion prospectiva del paisaje

    OpenAIRE

    Paegelow, Martin; Camacho Olmedo, Maria,; Menor Toribio, José

    2003-01-01

    Los SIG incluyen entre sus funciones de analisis aquellas destinadas a la modelizacion espacio-temporal. En este trabajo se presentan los resultados de la aplicacion de un método prospectivo, que combina el analisis de una serie cronologica de usos del suelo (cadenas de markov) con la puesta en relacion de estos usos y un conjunto de variables explicativas (evaluacion multicriterio), para, por ultimo, asignar a cada pixel una categoria de ocupacion del suelo (evaluacion multiobjetivo) en la f...

  1. Pinch Strengths in Healthy Iranian Children and Young Adult Population

    Directory of Open Access Journals (Sweden)

    Iman Dianat

    2015-03-01

    Full Text Available Background: Data on the physical strength capabilities are essential for design-ing safe and usable products and are useful in a wide range of clinical settings especially during treatment of disease affecting the function of the hand. The purpose of this study was to determine peak lateral pinch strength, key pinch strength, tip-to-tip pinch strength and three-jaw pinch strength exertions in a healthy Iranian children and young adult population.Methods: The study was conducted among 511 participants (242 males and 269 females aged 7-30 years. Measurements were carried out with both dominant and non-dominant hands in standard sitting posture using a B&L pinch gauge. Two repetitions of each strength measurement were recorded for each condition and the average value of the two trials was used in the subsequent analysis.Results: The results showed significant differences in the pinch strength data in terms of the age, gender and hand dominance. The lateral pinch strength, key pinch strength, tip-to-tip pinch strength and three-jaw pinch strength exertions by females were 68.4%, 68.8%, 78.8% and 81.8% of those exerted by males, respectively. Strength exertions with the non-dominant hand were 6.4%, 5.2%, 6.6% and 5.1% lower than strength exertions of the dominant hand for the lat-eral pinch strength, key pinch strength, tip-to-tip pinch strength and three-jaw pinch strength exertions, respectively.Conclusion: These findings can be used to fill the gaps in strength data for Iranian population.

  2. Delineasi Model Tentatif Sistem Geotermal dan Interpretasi Komprehensif Berdasarkan Analisis Geofisika, Geokimia, dan Geologi

    OpenAIRE

    Makhrani, Makhrani

    2013-01-01

    Telah didelineasi model tentatif sistem geothermal berdasarkan interpretasi komprehensif dari analisis geofisika, geokimia dan geologi yang dapat memperlihatkan lebih jauh tentang sistem geothermal di daerah penelitian. Analisis geofisika dilakukan untuk zonasi bawah permukaan (overburden, claycap dan reservoar) dan penentuan fasa fluida reservoar. Pola aliran hidrotermal bawah permukaan ditentukan dari analisis geofisika dan geokimia, didukung oleh analisis geologi. D...

  3. ANALISIS PENGARUH BIAYA BAURAN PROMOSI TERHADAP PENJUALAN PIPA PVC PADA PT. RAJAWALI JAYA SAKTI DI MAKASSAR

    OpenAIRE

    IRWANSYAH, MUHAMMAD

    2008-01-01

    Tujuan dari penelitian ini adalah untuk mengetahui perkembangan penjualan pipa PVC yang dicapai oleh perusahaan PT Rajawali Jaya Sakti di Makassar, untuk menganalisis sejauah mana pengaruh biaya bauran promosi melalui periklanan dan promosi penjualan dalam kaitannya dengan peningkatan penjualan Pipa PVC. Sedangkan metode analisis yang digunakan dalam penelitian ini adalah analisis deskriptif, analisis inferensial, uji parsial. Hasil analisis menunjukkan bahwa kegiatan promosi yang dilakuk...

  4. Analisis SWOT pada Toko Lestari Rattan and Furniture Jl. Gatot Subroto No. 457 Medan

    OpenAIRE

    Desira, Sheila

    2011-01-01

    Penelitian ini bertujuan untuk menganalisis SWOT yang ada pada Toko Lestari Rattan and Furniture. Analisis SWOT merupakan penilaian lingkungan internal berupa kekuatan (strength) dan kelemahan (weakness) serta lingkungan eksternal berupa peluang (opportunity) dan ancaman (treath). Analisis SWOT akan menghasilkan strategi yang tepat bagi perusahaan. Analisis SWOT umumnya digunakan pada perusahaan besar. Penelitian ini melihat penerapan analisis SWOT pada UKM (Usaha Kecil Mene...

  5. ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI INDEPENDENSI PENAMPILAN AKUNTAN PUBLIK

    Directory of Open Access Journals (Sweden)

    Ardiani Ika S.

    2012-03-01

    Full Text Available Tujuan dari penelitian ini adalah untuk menguji secara empiris faktor-faktor yang mempengaruhi independensi penampilan akuntan publik baik secara parsial dan simultan. Faktor-faktor tersebut adalah financial interests, hubungan bisnis dengan klien, pelayanan asuransi dan audit, hubungan antara klien atau yg diaudit dengan auditor, kompetisi antara Kantor Akuntan Publik (KAP, ukuran KAP dan audit fee. Populasi dalam penelitian ini adalah para auditor di akuntan publik di Semarang tahun 2009. Metode penyeleksian sampel yang digunakan adalah convenience sampling dan jumlah respondennya 35. Alat analisis yang digunakan adalah multiple regression analysis. Dimulai dengan analisis kuantitatif untuk mengetes validitas dan reabilitas. Kemudian dilanjutkan uji asumsi klasik termasuk normality, multicollinearity, and heteroscedastisity. Hasil menunjukkan bahwa 6 variabel yang sudah dikaji secara simultan dan partial tersebut mempunyai efek yang signifikan terhadap independensi penampilan akuntan publik dengan R square 0.749. The objective of this study is to test empirically the factors that influence the independence of public accountant appearance both partially and simultaneously. The factors cover financial interests, business relationships with clients, assurance services and audit services, the length of relationship between client or auditee and auditor, the competition between Public Accountan Offices (KAPs, the size of KAP, and audit fee. The population in this study was the auditors who worked in the public accountant’s office in Semarang in 2009. The sample selection method is a convenience sampling and the  number of  respondents are 35. The Analysis tools used is multiple regression analysis. It starts by applying quantitative analysis to test the validity and reliability. Then, it is continued by testing the classical assumptions which include normality, multicollinearity, and heteroscedastisity. The result shows that the six

  6. PRINSIP DAN METODE ANALISIS RISIKO KESEHATAN LINGKUNGAN

    Directory of Open Access Journals (Sweden)

    Defriman Djafri

    2014-04-01

    Full Text Available Analisis risiko kesehatan lingkungan merupakan penilaian atau penaksiran risiko kesehatan yang bisa terjadi di suatu waktu pada populasi manusia berisiko. Kajian prediktif ini menghasilkan karakteristik risiko secara kuantitatif, pilihan-pilihan manajemen risiko dan strategi komunikasi untuk meminimalkan risiko tersebut. Data kualitas lingkungan yang bersifat agent specific dan site specific, karakteristik antropometri dan pola aktivitas populasi terpajan dibutuhkan untuk kajian ini.

  7. PRINSIP DAN METODE ANALISIS RISIKO KESEHATAN LINGKUNGAN

    OpenAIRE

    Defriman Djafri

    2014-01-01

    Analisis risiko kesehatan lingkungan merupakan penilaian atau penaksiran risiko kesehatan yang bisa terjadi di suatu waktu pada populasi manusia berisiko. Kajian prediktif ini menghasilkan karakteristik risiko secara kuantitatif, pilihan-pilihan manajemen risiko dan strategi komunikasi untuk meminimalkan risiko tersebut. Data kualitas lingkungan yang bersifat agent specific dan site specific, karakteristik antropometri dan pola aktivitas populasi terpajan dibutuhkan untuk kajian ini.

  8. Z-Pinch Experiments with Shock Heating

    International Nuclear Information System (INIS)

    Two z-pinch experiments are reported. The first is a linear pinch whose results have encouraged the authors to construct the second, a toroidal system. In these experiments, a shock produces plasma temperatures higher than have been produced by ohmic heating. Theory predicts that with the higher temperatures the drift instabilities can be avoided resulting in a reduction of the anomalous field diffusion. MHD calculations predict stable configurations for some diffuse z-pinch profiles with a reversed Bz field external to the pinch, and a conducting wall. The linear z-pinch experiment has a length of 30 cm, a diameter of 10 cm and the discharge current is ∼ 200 kA. Initial values of Bθ of 80 kG/μs produce the shock. A magnetic energy storage system generates the necessary high voltage ≲ 80 kV. Probes measure the initial shock structure and plasma pressure profiles. Together with holographic interferometric density measurements, they yield temperatures (Ti + Te) of 750 eV and peak densities of 1016/cm3 with initial pressure of 30 mTorr of deuterium. The limit of sensitivity of the holographic technique prevents data from being obtained at a lower filling pressure where higher plasma temperatures should be obtained. The plasma column exhibits gross stability for times of the order of the time scale of the experiment (∼8 μs). One-dimensional MHD calculations are performed both with classical and anomalous resistivities. The results, including density and magnetic field profiles, are compared with experiment. The toroidal experiment has a major diameter of 76 cm and a minor diameter of 10.25 cm. A 500 kj inductive energy storage system develops a peak voltage of ≤ 320 kV around the circumference of the torus with maximum plasma currents of about 200 kA. Iron cores couple the primary to the plasma secondary circuit. Toroidal equilibrium calculations have been made for diffuse plasma profiles. A numerical stability analysis of these toroidal equilibria, free

  9. ANALISIS DE COSTEO PARA UN SISTEMA DE PRODUCCION DE LECHERIA ESPECIALIZADA "UN ACERCAMIENTO AL ANÁLISIS ECONÓMICO EN GANADERÍA DE LECHE": ESTUDIO DE CASO

    Directory of Open Access Journals (Sweden)

    GLORIA P. RÍOS ATEHORTÚA

    2008-01-01

    Full Text Available Con este estudio se pretende mostrar a pequeños y medianos productores de sistemas de producción de lechería especializada, un método adecuado para determinar costos de producción, mediante la estructuración de centros de costos de los procesos productivos allí identificados (praderas, cría y levante y centros de utilidades (producción de leche; herramienta que se convierte en la mayor fuente de información interna en las empresas, con el fin de posibilitar la toma de decisiones administrativas adecuadas. Para el estudio de caso, fue seleccionada La Pradera, finca ubicada en la vereda La Almería, municipio de la Unión, Antioquia. Los análisis económicos muestran el comportamiento de los diferentes elementos de costo en la obtención del costo unitario de producción por: litro de leche, kilogramo de pasto, mantenimiento promedio por día de un ternero y de una novilla.

  10. Analisis económico del proyecto de montaje de un módulo de deshidratación en un central azucarero cubano para la mezcla de alcohol - gasolina

    Directory of Open Access Journals (Sweden)

    Alfredo Torres-Fernández

    2013-01-01

    Full Text Available La adición de este tipo de alcohol a la gasolina permite aumentar su octano, sustituyen- do el tetraetilo de plomo, sin la utilización de otros componentes de origen fósil de alto valor agregado (naftas reformadas, isomerizadas, craqueadas, alquiladas, etc. Se está trabajando en Cuba en la implementación de un programa con vistas a producir etanol combustible para su mezcla con las gasolinas cubanas en un rango de 8 a 10 %. Se hace el análisis económico de cuatro variantes en la ejecución del proyecto de pro- ducción de la mezcla alcohol - gasolina, utilizando el programa computacional COMFAR III Expert, el cual permite realizar un análisis de sensibilidad para conocer las variaciones en los indicadores financieros al cambiar el monto de las inversiones asociadas al equipamiento de los diferentes objetos de obra, lo que resulta un elemento muy valioso en la toma de decisiones en el proceso inversionista.

  11. Interrupted z-pinch in argon

    International Nuclear Information System (INIS)

    The pinch effect in a low-pressure discharge in air between two cone-shaped copper electrodes was investigated. The paraxial dense part of the z-pinch became interrupted due to the barrel shape of the magnetic and electric fields, and two relatively stable plasma jets, connected with the electrode tips, were formed in the discharge shortly after the breakdown. Later a high-density ellipsoidal structure with a sharp boundary formed. Michelson interferometry and the Schlieren method, respectively, were used in measurements of the plasma density in the discharge channel and in the small inhomogeneity regions. A distinct filamentary structure of the plasma jets was well seen in the Schlieren pictures. The electron temperature was calculated from the intensities of spectral lines and of continuum radiation in the visible region. (J.U.) 1 fig., 3 refs

  12. Field mapping of the KATRIN pinch magnet

    International Nuclear Information System (INIS)

    The Karlsruhe Tritium Neutrino experiment aims to probe the effective mass of the electron antineutrino in a model-independent way with an unsurpassed sensitivity of 200 meV/c2 (90% C.L.). The energy spectrum of the electrons from Tritium β-decay is analyzed by an electrostatic spectrometer which is based on the MAC-E filter principle. The so-called PINCH magnet - a superconducting solenoid located at the end of the spectrometer - is a crucial part of the MAC-E filter and its field strength of 6 T is directly related to the sensitivity of the experiment. Thus, a clear understanding of its field stability and field map is indispensable for the success of KATRIN. Along with an overview of the KATRIN experiment and the MAC-E filter principle this poster presents the results of a detailed study of the PINCH magnet's field map obtained with a 3-axis Hall probe.

  13. Evolution of the MHD sheet pinch

    International Nuclear Information System (INIS)

    A magnetohydrodynamic (MHD) problem of recurrent interest for both astrophysical and laboratory plasmas is the evolution of the unstable sheet pinch, a current sheet across which a dc magnetic field reverses sign. The evolution of such a sheet pinch is followed with a spectral-method, incompressible, two-dimensional, MHD turbulence code. Spectral diagnostics are employed, as are contour plots of vector potential (magnetic field lines), electric current density, and velocity stream function (velocity streamlines). The nonlinear effect which seems most important is seen to be current filamentation: the concentration of the current density onto sets of small measure near a mgnetic X point. A great deal of turbulence is apparent in the current distribution, which, for high Reynolds numbers, requires large spatial grids (greater than or equal to (64)2). 11 figures, 1 table

  14. Quark-hadron duality: pinched kernel approch

    CERN Document Server

    Dominguez, C A; Schilcher, K; Spiesberger, H

    2016-01-01

    Hadronic spectral functions measured by the ALEPH collaboration in the vector and axial-vector channels are used to study potential quark-hadron duality violations (DV). This is done entirely in the framework of pinched kernel finite energy sum rules (FESR), i.e. in a model independent fashion. The kinematical range of the ALEPH data is effectively extended up to $s = 10\\; {\\mbox{GeV}^2}$ by using an appropriate kernel, and assuming that in this region the spectral functions are given by perturbative QCD. Support for this assumption is obtained by using $e^+ e^-$ annihilation data in the vector channel. Results in both channels show a good saturation of the pinched FESR, without further need of explicit models of DV.

  15. LASL toroidal reversed-field pinch programme

    International Nuclear Information System (INIS)

    The determination of the absolute energy loss due to radiation from impurities in the LASL toroidal reversed-field pinch experiment ZT-S is reported. The measurements show that over half the energy loss is accounted for by this mechanism. Thomson-scattering electron density measurements indicate only a gradual increase in temperature as the filling pressure is reduced, indicating an increased energy loss at lower pressures. Cylindrical and toroidal simulations of the experiment indicate either that a highly radiative pinch boundary or anomalous transport is needed to match the experimental results. New effects on the equilibrium due to plasma flows induced by the toroidal geometry are predicted by the toroidal simulations. The preliminary results on the low-temperature discharge cleaning of the ZT-S torus are reported. A description of the upgrade of the ZT-S experiment and the objectives, construction and theoretical predictions for the new ZT-40 experiment are given. (author)

  16. A study in blood at pinch

    CERN Document Server

    Kar, Shantimoy; Chaudhury, Kaustav; Maiti, Tapas Kumar; Chakraborty, Suman

    2016-01-01

    The complex fluidic nature of blood, though necessary to serve different physiological purposes, gives rise to daunting challenges in developing unified conceptual paradigm describing the underlying physics of blood at pinch, which may otherwise be essential for understanding various bio-technological processes demanding precise and efficient handling of blood samples. Intuitively, a blood-drop may be formed simply by dripping. However, the pinch-off dynamics leading to blood-drop-breakup is elusively more complex than what may be portrayed by any unique model depicting the underlying morpho-dynamics, as our study reveals. With blood samples, here we observe two distinctive modes of the breakup process. One mode corresponds to incessant collapsing of a liquid-neck, while in other mode formation and thinning of an extended long thread leads to the breakup and drop formation. We further show that these modes are respectively described by power law and exponential law based universal scaling dynamics, depicting ...

  17. ANALISIS TINGKAT PENDAPATAN PEDAGANG CANANG DI PASAR BADUNG

    Directory of Open Access Journals (Sweden)

    Surya Dewi Rustariyuni

    2015-12-01

    Full Text Available This studyanalyzes thecharacteristic of “canang”sellers, their economicactivities, their revenues, the factors which influencethem to chooseBadung Market for selling their products and theircontributions in their household economy. As a matter of fact,all of Hindu ismpeoplein Bali use canang everyday for conductingall ceremonies, but only few people whomake canang. It has occured foryears. The method used for analizing the data isdescriptive analysis. The result shows thatthe canang sellersare mostlyfrom Bali. They are dominated by married women atthe age of 15 up to 35 years old. Then, theireducational backgroundaresenior high schools. They start selling early in the morning and stop their activities in the evening.Finally, usually the sellers get much money when there is a big ceremony.Penelitian ini menganalisis karakteristik penjual "canang", kegiatan ekonominya, pendapatannya, faktor-faktor yang mempengaruhi penjual canang untuk memilih Pasar Badung sebagai tempat untuk menjual canangnya dan kontribusi penjual canang dalam perekonomian rumah tangga. Sebenarnya, semua orang Hindu di Bali menggunakan canang setiap hari untuk melakukan semua upacara, tetapi hanya sedikit orang yang membuat canang. Ini telah terjadi selama bertahun-tahun. Metode yang digunakan untuk menganalisis data disini adalah analisis deskriptif. Hasil penelitian menunjukkan bahwa para penjual canang sebagian besar dari Bali. Mereka didominasi oleh perempuan yang sudah menikah danusianya antara 15 hingga 35 tahun. Kemudian, latar belakang pendidikan mereka adalah sekolah menengah atas. Mereka mulai menjual canang di pagi hari dan selesai di malam hari. Biasanya para penjual mendapatkan uang banyak ketika ada upacara besar.

  18. Analysis of passive systems as a tool for energy saving in buildings: solar control; Analisis de sistemas pasivos como herramienta para el ahorro de energia en edificaciones: Control solar

    Energy Technology Data Exchange (ETDEWEB)

    Saravia, Maricela; Morillon Galvez, David [Instituto de Ingenieria, UNAM, Mexico, D. F. (Mexico)

    1999-07-01

    A bioclimatic study of El Salvador is presented, with the purpose of using window eaves as elements of passive solar control and to determine the optimal angles of orientation, in order to diminish the thermal gains by direct solar radiation and to manage to get close to the comfort conditions. The former with the intention of integrating measures that help to obtain energy efficiency and comfortable buildings, for the conditions of warm humid climate, characteristic of a Central American country like El Salvador. Besides offering a document of consultation among the professionals dedicated to the design and as base of bioclimatic considerations that must have the construction regulations. As a conclusion the optimal angles of eaves for each orientation are presented and a quantitative estimation of the savings that would imply not to consume electrical energy in cooling systems using these elements as a protection to the direct solar radiation. [Spanish] Se presenta un estudio del bioclima de El Salvador, con el fin de utilizar aleros de ventana como elementos de control solar pasivo y determinar los angulos optimos por orientacion, para disminuir las ganancias termicas por radiacion solar directa y lograr acercar a las condiciones de confort. Lo anterior con el objeto de integrar medidas que coadyuven a lograr edificios energeticamente eficientes y confortables, para las condiciones de clima calido humedo, caracteristico de un pais centroamericano como El Salvador. Ademas de brindar un documento de consulta entre los profesionales dedicados al dise y como base de consideraciones bioclimaticas que debe tener el reglamento de construcciones. Como conclusion se presentan los angulos optimos de alero por cada orientacion y una estimacion cuantitativa del ahorro que implicaria el no consumir energia electrica en sistemas de enfriamiento utilizando estos elementos como una proteccion a la radiacion solar directa.

  19. High-intensity-laser-driven Z pinches

    International Nuclear Information System (INIS)

    Experiments were performed in which ultrahigh intensity laser pulses (I>5x1019 W cm-2) were used to irradiate thin wire targets. It was observed that such interactions generate a large number of relativistic electrons which escape the target and induce multimega ampere return currents within the wire. MHD instabilities can subsequently be observed in the pinching plasma along with field emission of electrons from nearby objects. Coherent optical transition radiation from adjacent objects was also observed

  20. Singularities in droplet pinching without viscosity

    CERN Document Server

    Eggers, J

    1997-01-01

    A model for the pinching of an inviscid liquid column, originally developed by Lee, is considered. We find that Lee's model has a singularity in the curvature at a finite thread radius, and therefore does not describe breakup. However, the observed steepening of the profile corresponds to experiments with fluids at low viscosity. The singularity has similarity form, which we compute analytically. The result agrees well with numerical simulations of Lee's model.

  1. Persistence of a pinch in a pipe

    OpenAIRE

    Mahadevan, L.; Vaziri, A.; Das, Moumita

    2006-01-01

    The response of low-dimensional solid objects combines geometry and physics in unusual ways, exemplified in structures of great utility such as a thin-walled tube that is ubiquitous in nature and technology. Here we provide a particularly surprising consequence of this confluence of geometry and physics in tubular structures: the anomalously large persistence of a localized pinch in an elastic pipe whose effect decays very slowly as an oscillatory exponential with a persistence length that di...

  2. Electroweak pinch technique to all orders

    International Nuclear Information System (INIS)

    The generalization of the pinch technique to all orders in the electroweak sector of the Standard Model within the class of the renormalizable 't Hooft gauges, is presented. In particular, both the all-order PT gauge-boson- and scalar-fermion vertices, as well as the diagonal and mixed gauge-boson and scalar self-energies are explicitly constructed. This is achieved through the generalization to the Standard Model of the procedure recently applied to the QCD case, which consists of two steps: (i) the identification of special Green's functions, which serve as a common kernel to all self-energy and vertex diagrams and (ii) the study of the (on-shell) Slavnov-Taylor identities they satisfy. It is then shown that the ghost, scalar and scalar-gauge-boson Green's functions appearing in these identities capture precisely the result of the pinching action at arbitrary order. It turns out that the aforementioned Green's functions play a crucial role, their net effect being the non-trivial modification of the ghost, scalar and scalar-gauge-boson diagrams of the gauge-boson- or scalar-fermion vertex we have started from, in such a way as to dynamically generate the characteristic ghost and scalar sector of the background field method. The pinch technique gauge-boson and scalar self-energies are also explicitly constructed by resorting to the method of the background-quantum identities

  3. Staged Z-pinch for Fusion

    Science.gov (United States)

    Wessel, Frank; Rahman, Hafiz; Ney, Paul; Darling, Tim; McKee, Erik; Covington, Aaron; Beg, Farhat; Valenzuela, Julio; Narkis, Jeff; Presura, Radu

    2015-11-01

    The Staged Z-pinch (SZP) is configured as a plasma shell imploding onto an uniform, plasma fill (50:50 Deuterium:Tritium); the pinch is pre-magnetized, with an axial Bz field. Gas-puff experiments, at the University of California, Irvine, 1.25 MA, 1.25 μs, and 50 kJ, demonstrated that the implosion was stable, as primary (DD) and secondary (DT) neutrons were produced at peak compression. Subsequent analysis accounts for the stability and neutron yield, indicating that the SZP implosion is magneto-inertial, shock-driven, with magneto-sonic shocks in the liner and ordinary (sonic) shocks in the target. The shock waves preheat the target, as a stable, current-carrying, shock front forms at the interface. Near-term, the SZP team will test pinch loads on the 1 MA, 130 ns, 100 kJ University of Nevada, Reno, Nevada Terawatt, Zebra Facility. This paper details the context and our specific plans for the upcoming experiments, as well as our recent simulations predicting breakeven fusion on existing devices. Funded by the US Department of Energy, ARPA-E, Control Number 1184-1527.

  4. ''Turbulent Equipartition'' Theory of Toroidal Momentum Pinch

    International Nuclear Information System (INIS)

    The mode-independent part of magnetic curvature driven turbulent convective (TuroCo) pinch of the angular momentum density (Hahm et al., Phys. Plasmas 14,072302 (2007)) which was originally derived from the gyrokinetic equation, can be interpreted in terms of the turbulent equipartition (TEP) theory. It is shown that the previous results can be obtained from the local conservation of 'magnetically weighted angular momentum density', nmi U#parallel# R/B2, and its homogenization due to turbulent flows. It is also demonstrated that the magnetic curvature modification of the parallel acceleration in the nonlinear gyrokinetic equation in the laboratory frame, which was shown to be responsible for the TEP part of the TurCo pinch of angular momentum density in the previous work, is closely related to the Coriolis drift coupling to the perturbed electric field. In addition, the origin of the diffusive flux in the rotating frame is highlighted. Finally, it is illustrated that there should be a difference in scalings between the momentum pinch originated from inherently toroidal effects and that coming from other mechanisms which exist in a simpler geometry.

  5. Turbulent Equipartition Theory of Toroidal Momentum Pinch

    Energy Technology Data Exchange (ETDEWEB)

    T.S. Hahm, P.H. Diamond, O.D. Gurcan, and G. Rewaldt

    2008-01-31

    The mode-independet part of magnetic curvature driven turbulent convective (TuroCo) pinch of the angular momentum density [Hahm et al., Phys. Plasmas 14,072302 (2007)] which was originally derived from the gyrokinetic equation, can be interpreted in terms of the turbulent equipartition (TEP) theory. It is shown that the previous results can be obtained from the local conservation of "magnetically weighted angular momentum density," nmi U|| R/B2, and its homogenization due to turbulent flows. It is also demonstrated that the magnetic curvature modification of the parallel acceleration in the nonlinear gyrokinetic equation in the laboratory frame, which was shown to be responsible for the TEP part of the TurCo pinch of angular momentum density in the previous work, is closely related to the Coriolis drift coupling to the perturbed electric field. In addition, the origin of the diffusive flux in the rotating frame is highlighted. Finally, it is illustratd that there should be a difference in scalings between the momentum pinch originated from inherently toroidal effects and that coming from other mechanisms which exist in a simpler geometry.

  6. ANALISIS MATRIKS BOSTON CONSULTING GROUP (BCG) UNTUK MEMENANGKAN STRATEGI ORGANISASI

    OpenAIRE

    Haryadi Sarjono; Engkos Achmad Kuncoro

    2013-01-01

    Penelitian ini bertujuan untuk mengetahui posisi tingkat pertumbuhan pasar pada perguruan tinggi khususnya Sekolah Tinggi berdasarkan market share, menggunakan matriks BCG. Unit analisis adalah semua perguruan tinggi swasta yang termasuk dalam Kopertis Wilayah III DKI Jakarta, yang terdiri dari Universitas, Sekolah Tinggi, Institut, dan Akademi. Objek analisis adalah jumlah penerimaan mahasiswa baru. Metode pengumpulan data yang dilakukan dalam penulisan ini adalah dengan metode ...

  7. Analisis SWOT Dalam Upaya Meningkatkan Keunggulan Bersaing Pada Salon Cleopatra

    OpenAIRE

    Syafitri, Yudhi

    2010-01-01

    Tujuan penelitian adalah untuk mengetahui dan menganalisis peranan analisis SWOT dalam upaya meningkatkan keunggulan bersaing pada Salon Cleopatra. Kesimpulan yang diperoleh penulis berdasarkan hasil dari penelitian yang dilakukan dengan menggunakan analisis SWOT dan Matriks SPACE dengan strategi agresif yang dilakukan oleh Salon Cleopatra sudah cukup baik, akan tetapi Salon Cleopatra melakukan strategi berdasarkan pengalaman, insting dan keadaan pasar, bukan dilakukan berdasarkan strategi a...

  8. High-density fusion and the Z-pinch

    International Nuclear Information System (INIS)

    The formation of a Z-pinch in dense gas is investigated using numerical modeling in one and two dimensions. Hot, dense Z-pinches are calculated with n approximately 2 x 1021cm3 and T = 10 keV. Relaxation by sausage instability of an unstable pinch profile to a marginally stable one is calculated along with end losses in 2 dimensions to show that, if plasma is confined for N = 50 to 200 sound transits across the radius a, pinches with length L = Na are of interest for fusion power. A conceptual, ''no-wall'' fusion reactor is discussed. (author)

  9. Thermonuclear Fusion with the Sheared Flow Stabilized Z-Pinch

    CERN Document Server

    Winterberg, F

    2008-01-01

    Two basic approaches to producing thermonuclear fusion with a sheared flow stabilized z-pinch are considered. One consists of heating the entire length of the z-pinch column to the required temperatures. The other basic approach considered here involves the concept of fast ignition. A localized "hot-spot" is produced under the proper conditions to ignite a thermonuclear burn wave in the z-pinch plasma. Here we demonstrate that sheared flow stabilization is more efficient in the fast-ignition method with isentropic compression then in a z-pinch where the entire plasma column is heated.

  10. Analisis de la dispersion del PIB per capita en las regiones de la Republica Mexicana, 1940-2009

    OpenAIRE

    Manuel Gomez-Zaldivar

    2012-01-01

    En el presente articulo se propone y emplea un metodo para el analisis de la convergencia relativa para regiones de la Republica Mexicana, en el periodo 1940-2009. Los resultados indican que todas las regiones analizadas convergen en este sentido hasta la decada de los ochenta. Sin embargo, a partir de entonces, la evolucion de la dispersion en las diferentes regiones fue diversa. La dispersion relativa en los estados de la Frontera norte se incrementa en relacion al del resto de las regiones...

  11. TECNOLOGÍAS PARA LA INCLUSIÓN SOCIAL Y DINAMICAS DESARROLLO SUSTENTABLE. ANALISIS SOCIO-TÉCNICO DE EXPERIENCIAS DE DESARROLLO LOCAL BASADAS EN EL APROVECHAMIENTO DE ENERGÍAS RENOVABLES

    Directory of Open Access Journals (Sweden)

    Santiago Manuel Garrido

    2014-06-01

    Full Text Available 800x600 Este trabajo tiene como objetivo principal analizar, desde una perspectiva socio-técnica, un conjunto de iniciativas, proyectos y políticas orientadas al aprovechamiento de energías renovables en la Argentina, prestando atención particular a las acciones desarrolladas con el fin de promover dinámicas de desarrollo local sustentable e inclusión social. En los últimos años en Argentina, se están implementando diversas experiencias y proyectos de este tipo. Sin embargo, la mayoría de estas experiencias, proyectos y políticas se manifiestan en última instancia como paliativos, ya que proveen simplemente el recurso energético, ofreciendo una solución puntual a un problema complejo. De este modo, no se contemplan las necesidades energéticas vinculadas a actividades productivas o estrategias de desarrollo local. Para esto se presentan, en primer lugar, un conjunto de herramientas analíticas que permitirán proceder a la desconstrucción y re-construcción de los problemas y las soluciones vinculadas al desarrollo e implementación de políticas y proyectos de investigación en el campo de las energías renovables. A continuación se presenta un resumen de la trayectoria socio-técnica de algunas ejemplos de este tipo de experiencias en Argentina, y, finalmente, se concluye con algunas observaciones acerca del proceso de co-construcción de tecnologías, problemas sociales, políticas públicas y dinámicas de desarrollo local.  Normal 0 21 false false false ES-AR X-NONE X-NONE MicrosoftInternetExplorer4

  12. ANALISIS PERBANDINGAN SPAP, IAS DAN SPKN

    OpenAIRE

    Maylia Pramono Sari

    2012-01-01

    Dalam mewujudkan Good Goveronance  akan dilakukan analisis perbandingan mengenai standar pemeriksaan nasional yaitu SPAP, ISA, dan SPKN untuk menemukan standar yang lebih tepat dan lebih lengkap untuk pemeriksaan sektor publik. Persamaan SPKN dan ISS  adalah tanggungjawab manajemen dan tanggungjawab auditor sedangkan perbedaannya adalah badan yang menerbitkannya. Perbedaan yang mendasar terletak pada karakter pemeriksaan BPK. Karakter tersebut adalah keharusan pemeriksa BPK untuk merancang ...

  13. Analisis Mineralogi Batuan Gua Lakasa, Buton.

    OpenAIRE

    Massinai, Muhammad Altin; Rahmat, Adnan

    2014-01-01

    Gua Lakasa merupakan salah satu gua di Buton yang berpotensi dengan kandungan mineral-mineral yang bernilai ekonomis. Penelitian di Gua Lakasa bertujuan menentukan jenis-jenis batuan dan mineral pembentuk speleothem /ornament gua. Metode penelitian yang digunakan adalah analisis mineralogi. Hasil penelitian menunjukkan bahwa Gua Lakasa merupakan gua batugamping (karst).Jenis-jenis batuan yang terdapat di Gua Lakasa berupa dolomite, fosil gampingan, batugamping kompak dan konglomerat, sedangk...

  14. Análise da viabilidade econômica para produção de flores em Umuarama, noroeste do Paraná. = Analisys of the economic viability of fl ower production in Uuarama, northwest Paraná.

    Directory of Open Access Journals (Sweden)

    Claudia Regina Dias-Arieira

    2008-12-01

    Full Text Available O noroeste do Paraná caracteriza-se pelas atividades agropecuárias, com ênfase na exploração de grandesculturas, como soja, milho e cana-de-açúcar e na pecuária de corte. Contudo, outras oportunidades têm se apresentado dadaa crescente dinâmica da atividade econômica brasileira. A produção de fl ores é uma alternativa para os pequenos e médiosempresários rurais, e uma atividade em expansão no Brasil. Além disso, fatores como difi culdades de escoamento, transportee armazenamento, antes limitantes dessa cultura, hoje têm sido superados com pesquisas e tecnologia. No entanto, antes de seefetivar o investimento, o empresário deve fazer um estudo da viabilidade técnica e econômica da atividade ou cultura a serimplantada, conhecer suas peculiaridades e estar apto a aproveitar as oportunidades e a proteger-se das ameaças do negócio.Dentre tais peculiaridades, deve-se destacar a estrutura de custos da atividade, identifi cando os principais fatores de produçãoque afetam o rendimento e a rentabilidade do negócio. Objetivou-se com esse trabalho avaliar a viabilidade de implantação emanutenção de uma estrutura de produção de fl ores em Umuarama, região noroeste no Paraná. = The northeastern of Paraná is characterized by agribussines activities with enfasis on agricultural exploration, assoybean, corn, sugar cane and meat cattle. However, others opportunities are present, by moment of brasilian economy. Theflowers production is an alternative for the agricultural entrepeneurs and an activity in growth in Brazil. Moreover, factorsas diffi cults of dry, transport and stock, before limitantes for this culture, have been eliminated with research and tecnology.However, if accomplishing the investment, the entrepreneur must make a study of the economic and technological viability ofthe activity or culture to be implanted, to know your peculiarities and left it apt to use to advantage the chances and to protectthemselves of the

  15. Characteristic Differences Between Wire and Foil X-pinches

    Science.gov (United States)

    Collins, Gilbert; Valenzuela, Julio; Krasheninnikov, Igor; Beg, Farhat; Wei, Mingsheng

    2015-11-01

    We conducted X-pinch experiments using laser-cut Ni and Cu foils on the 250kA GenASIS current driver at UC San Diego. General Atomics' Laser Micro-Machining (LMM) Center manufactured the X's. To characterize the foil X-pinches, we measured and compared the evolution, emission spectra, yield, and source size of these new arrays to that of comparably massed wire X-pinches on the same driver. Diagnostics included Si PN diodes and diamond PCDs, optical probing, X-ray spectroscopy, an XUV framing camera, a slit-wire camera, and current probes. We used novel structures machined into the crosspoint in an effort to better understand the effects of the initial geometry on the final pinch and to spatially confine the source location. Some designs entirely prohibited pinching. In other designs, when pinching occurred, the sources were comparable to ideal wire shots on GenASIS both in size (at or less than five microns) and X-ray flux (5-10 MW @ 1-10 keV). The data collected here also show considerable differences between successful foil and wire pinches. The X-ray spectra are not identical, and we find that the foil X's produce a single >2.5 keV emission pulse with none of the additional later and longer-lasting hard emission pulses found in wire X-pinches.

  16. Investigation on the pinch point position in heat exchangers

    Science.gov (United States)

    Pan, Lisheng; Shi, Weixiu

    2016-06-01

    The pinch point is important for analyzing heat transfer in thermodynamic cycles. With the aim to reveal the importance of determining the accurate pinch point, the research on the pinch point position is carried out by theoretical method. The results show that the pinch point position depends on the parameters of the heat transfer fluids and the major fluid properties. In most cases, the pinch point locates at the bubble point for the evaporator and the dew point for the condenser. However, the pinch point shifts to the supercooled liquid state in the near critical conditions for the evaporator. Similarly, it shifts to the superheated vapor state with the condensing temperature approaching the critical temperature for the condenser. It even can shift to the working fluid entrance of the evaporator or the supercritical heater when the heat source fluid temperature is very high compared with the absorbing heat temperature. A wrong position for the pinch point may generate serious mistake. In brief, the pinch point should be founded by the iterative method in all conditions rather than taking for granted.

  17. End plugging of a linear theta pinch by pulsed mirrors

    International Nuclear Information System (INIS)

    It is shown that by suitably pulsing a magnetic mirror end plug of a linear theta pinch, one can substantially reduce the end loss. A system consisting of a linear pinch with sequentially pulsed multimirror end plugs is proposed which shows promise of fusion feasibility. (author)

  18. Investigation on the Pinch Point Position in Heat Exchangers

    Institute of Scientific and Technical Information of China (English)

    PAN Lisheng; SHI Weixiu

    2016-01-01

    The pinch point is important for analyzing heat transfer in thermodynamic cycles.With the aim to reveal the importance of determining the accurate pinch point,the research on the pinch point position is carried out by theoretical method.The results show that the pinch point position depends on the parameters of the heat transfer fluids and the major fluid properties.In most cases,the pinch point locates at the bubble point for the evaporator and the dew point for the condenser.However,the pinch point shifts to the supercooled liquid state in the near critical conditions for the evaporator.Similarly,it shifts to the superheated vapor state with the condensing temperature approaching the critical temperature for the condenser.It even can shift to the working fluid entrance of the evaporator or the supercritical heater when the heat source fluid temperature is very high compared with the absorbing heat temperature.A wrong position for the pinch point may generate serious mistake.In brief,the pinch point should be founded by the iterative method in all conditions rather than taking for granted.

  19. Electrophoretic analisys to detect and quantify additional whey in milk and dairy beverages Análise eletroforética para detectar e quantificar soro de leite adicional em leite e bebidas lácteas

    Directory of Open Access Journals (Sweden)

    Elizabeth Maria Talá de SOUZA

    2000-12-01

    Full Text Available Polyacrylamide gel electrophoresis, SDS-PAGE system, was adjusted to detect the presence of additional whey in dairy beverages distributed in a Brazilian Government School Meals Program. Aqueous solutions of samples in 8 M urea were submitted to a polyacrylamide gel gradient (10% to 18%. Gel scans from electrophoresis patterns of previously adulterated milk samples showed that caseins peak areas decreased while peak areas of beta -lactoglobulin plus alpha -lactalbumin increased as the percentage of raw milk powder replaced by whey powder increased. The relative densitometer areas of caseins or beta -lactoglobulin plus alpha -lactalbumin plotted against the percentage of whey added to the raw milk showed a linear correlation coefficient square higher than 0.97. The caseins plot was used to determine the percentage of additional whey in 116 dairy beverages, chocolate or coffee flavor. Considering that the lowest relative caseins concentration found in commercial milk powder samples by the present method was 72%, the dairy beverages containing caseins percentages equal to or higher than this value were considered free of additional whey. Based on this criterion, about 49% of the coffee-flavor dairy beverages and 29% of the chocolate-flavor beverages, among all the samples analyzed were adulterated with whey protein to reach the total protein contents specified on their labels. The present method showed a sensitivity of 5% to additional whey.A adulteração de bebidas lácteas, distribuídas no Programa Nacional da Merenda Escolar, pela adição de soro, foi investigada através da análise eletroforética em sistema de SDS-PAGE. Soluções aquosas de amostras em uréia 8M, foram submetidas a um gradiente de 10% a 18% de gel de poliacrilamida. Após a eletroforese, o gel corado com "Comassie Blue" foi submetido à densitometria para identificação e quantificação das proteínas lácteas. A partir de amostras de leite em pó, previamente

  20. Plasma Flow in a Theta Pinch

    International Nuclear Information System (INIS)

    In the absence of instabilities, the loss of plasma in a theta pinch is almost wholly due to flow along the magnetic field to the ends of the coil. Thus, in order to understand the containment of the plasma, it is necessary to study the transient axial flow of the plasma. This is done in the present work by setting up a simple model of the plasma in which the problem is reduced to that of studying a one-dimensional flow. Initially a similarity area-wave is propagated from the open ends. The properties of this wave and the resulting loss are calculated. For high-β plasmas the plasma is lost rapidly behind the wave-front. However, the wave-front itself propagates very slowly and the resulting loss is consequently small. In these conditions the loss is approximately equal to that of the corresponding steady flow. For lower values of β the loss is much less than in the steady flow. When the rarefaction waves from the two ends reach the centre of the pinch they are reflected. The trajectory of the reflected wave is determined as a function of β and wave profiles calculated by numerical integration of the equations are presented. The flow may be reduced by applying increased fields at the ends of the pinch. In this case a rarefaction wave is propagated from these ''mirrors'', but behind the wave there is a region of uniform flow. This flow pattern is described and the resulting loss rate calculated. (author)

  1. Nonlocal Transport in the Reversed Field Pinch

    International Nuclear Information System (INIS)

    Several heuristic models for nonlocal transport in plasmas have been developed, but they have had a limited possibility of detailed comparison with experimental data. Nonlocal aspects introduced by the existence of a known spectrum of relatively stable saturated tearing modes in a low current reversed field pinch offers a unique possibility for such a study. A numerical modeling of the magnetic structure and associated particle transport is carried out for the reversed-field pinch experiment at the Consorzio RFX, Padova, Italy. A reproduction of the tearing mode spectrum with a guiding center code1 reliably reproduces the observed soft X-ray tomography. Following particle trajectories in the stochastic magnetic field shows the transport across the unperturbed flux surfaces to be due to a spectrum of Levy flights, with the details of the spectrum position dependent. The resulting transport is subdiffusive, and cannot be described by Rechester-Rosenbluth diffusion, which depends on a random phase approximation. If one attempts to fit the local transport phenomenologically, the subdiffusion can be fit with a combination of diffusion and inward pinch. It is found that whereas passing particles explore the stochastic field and hence participate in Levy flights, the trapped particles experience normal neoclassical diffusion. A two fluid nonlocal Montroll equation is used to model this transport, with a Levy flight defined as the motion of an ion during the period that the pitch has one sign. The necessary input to the Montroll equation consists of a time distribution for the Levy flights, given by the pitch angle scattering operator, and a distribution of the flight distances, determined numerically using a guiding center code. Results are compared to experiment. The relation of this formulation to fractional kinetics is also described.

  2. Interchange stability of noncircular reversed field pinches

    International Nuclear Information System (INIS)

    Interchange (Mercier) stability of toroidal reversed-field-pinch plasmas with noncircular cross-section is evaluated numerically. Marginally stable pressure profiles and beta values are produced. Most shapes, such as indented or vertically elongated, reduce stability by making the net magnetic curvature of the poloidal-field-dominated plasmas yet worse than that of the circle. Horizontally elongated plasmas slightly enhance stability beyond that of the circle as a result of increased shear produced by toroidicity. Such shear enhancement by the toroidal shift of magnetic surfaces might be exploited for future, more comprehensive studies

  3. XUV Radiation Emitted by Capillary Pinching Discharge

    Czech Academy of Sciences Publication Activity Database

    Vrbová, M.; Jančárek, A.; Vrba, Pavel; Nevrkla, M.; Kolař, P.

    Vol. 136. Dordrecht: Springer Proceedings in Physics , 2010 - (Lee, J.; Nam, C.; Janulewicz, K.), s. 257-262. (Springer Proceedings in Physics . 136). ISBN 978-94-007-1185-3. ISSN 0930-8989. [International Conference on X-Ray Laser s 2010/12th./. Gwangju (KR), 30.05.2010-04.06.2010] R&D Projects: GA MŠk LA08024 Institutional research plan: CEZ:AV0Z20430508 Keywords : Capillary Z-pinch * water window radiation source * RHMD Z engine Subject RIV: BH - Optics, Masers, Laser s http://www.springer.com/series/361

  4. What is a Reversed Field Pinch?

    Science.gov (United States)

    Escande, D. F.

    2015-12-01

    The following sections are included: * Introduction * Short description * Usefulness of the RFP configuration for fusion science and dynamo physics * Attractivity of the RFP configuration for a reactor * Challenges ahead * Lawson criterion * Intuitive model of magnetic self-reversal * Intuitive description of the dynamo * Necessity of a helical deformation * MHD simulations * From single to multiple helicity * Single helicity * Multiple helicity * Quasi single helicity * Experimental results * Multiple helicity * Quasi single helicity * Upgrade of the RFX device * From double to single magnetic axis * Analytical description of the single helicity RFP * Helical Grad-Shafranov equation * Parallel Ohm's law * Pinch-stellarator equation * Single helicity ohmic RFP states * Calculation of the dynamo * Conclusion * Acknowledgments * References

  5. Reversed field pinch experiments on HIT-1

    International Nuclear Information System (INIS)

    HIT-1 (Hiroshima Torus-1) is constructed to elucidate the basic physical phenomena in the reversed field pinch (RFP) plasma. Design of HIT-1 system started in April 1983 and construction of its major parts finished in December 1983. Computational analyses are performed to calculate the magnetic field distributions in the torus, the load current and voltage on the poloidal and toroidal circuits of HIT-1. The analytic methods and calculated results for the magnetic fields and the poloidal and toroidal circuits are described in detail. (author)

  6. Fusion Propulsion Z-Pinch Engine Concept

    Science.gov (United States)

    Miernik, J.; Statham, G.; Fabisinski, L.; Maples, C. D.; Adams, R.; Polsgrove, T.; Fincher, S.; Cassibry, J.; Cortez, R.; Turner, M.; Percy, T.

    2011-01-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Due to the great distances between the planets of our solar system and the harmful radiation environment of interplanetary space, high specific impulse (Isp) propulsion in vehicles with high payload mass fractions must be developed to provide practical and safe vehicles for human spaceflight missions. The Z-Pinch dense plasma focus method is a Magneto-Inertial Fusion (MIF) approach that may potentially lead to a small, low cost fusion reactor/engine assembly1. Recent advancements in experimental and theoretical understanding of this concept suggest favorable scaling of fusion power output yield 2. The magnetic field resulting from the large current compresses the plasma to fusion conditions, and this process can be pulsed over short timescales (10(exp -6 sec). This type of plasma formation is widely used in the field of Nuclear Weapons Effects testing in the defense industry, as well as in fusion energy research. A Decade Module 2 (DM2), approx.500 KJ pulsed-power is coming to the RSA Aerophysics Lab managed by UAHuntsville in January, 2012. A Z-Pinch propulsion concept was designed for a vehicle based on a previous fusion vehicle study called "Human Outer Planet Exploration" (HOPE), which used Magnetized Target Fusion (MTF) 3 propulsion. The reference mission is the transport of crew and cargo to Mars and back, with a reusable vehicle.

  7. Rotational instability in a linear theta pinch

    International Nuclear Information System (INIS)

    The m=1 ''wobble'' instability of the plasma column in a 5-m linear theta pinch has been studied using an axial array of orthogonally viewing position detectors to resolve the wavelength and frequency of the column motion. The experimental results are compared with recent theoretical predictions that include finite Larmor orbit effects. The frequency and wavelength characteristics at saturation agree with the predicted dispersion relation for a plasma rotating faster than the diamagnetic drift speed. Measurements of the magnetic fields at the ends of the pinch establish the existence of currents flowing in such a way that they short out the radial electric fields in the plasma column. The magnitude of rotation, the observed delay in the onset of m=1 motion, and the magnitude of end-shorting currents can all be understood in terms of the torsional Alfven waves that communicate to the central plasma column the information that the ends have been shorted. The same waves are responsible for the torque which rotates the plasma and leads to the observed m=1 instability. Observations of the plasma in the presence of solid end plugs indicate a stabilization of high-m number modes and a reduction of the m=1 amplitude

  8. Processes governing pinch formation in diodes

    International Nuclear Information System (INIS)

    The process of pinch formation in large aspect ratio diodes has been studied by means of streak photography and time-resolved x-ray detectors. A tight pinch is formed at the anode center by a collapsing thin hollow electron beam. The collapse velocity depends, among other things, on the type of material in the top 1 μm layer of the anode. In a tentative model it is assumed that an anode plasma is at least partially created from gases released from the surface layer of the anode by the heating action of the beam. These gases are ionized by primary, backscattered, and secondary electrons. Ions emitted from this plasma modify the electron trajectories in the diode leading to a radial collapse of the hollow electron beam. The observed monotonic dependence of the collapse velocity on the atomic number of the anode material can be explained by the smooth dependence on Z of both the specific heat and the electron backscatter coefficient. In the case of high-Z anodes the ion expansion time appears to be the factor limiting the collapse velocity. Detailed experimental data are presented

  9. Modal analysis of electromechanical oscillations in electrical power systems; Analisis modal de oscilaciones electromecanicas en sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Calderon-Guizar, J.G [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: jgcg@iie.org.mx

    2008-10-15

    The presence of electromechanical oscillations in any electrical power system is a typical characteristic of this kind of systems. Provided the damping associated with these oscillations lies above of a minimum specified value, the occurrence of these oscillations is not considered as a threat to the system operation. This paper focuses the attention on the application of modal analysis for assessing the dynamical behavior of a power system subjected to small disturbances for different operating conditions and transmission system topologies, as well. The reported results indicate, that modal analysis enables a straight identification of the causes that contribute negatively to the damping of the electromechanical modes. [Spanish] La presencia de oscilaciones electromecanicas en cualquier Sistema Electrico de Potencia (SEP) es una caracteristica propia de estos sistemas. Mientras el amortiguamiento asociado con este tipo de oscilaciones se encuentre dentro de los limites considerados como aceptables para la operacion continua de este tipo de sistemas, el surgimiento de estas no se considera una amenaza para la operacion segura del SEP. El presente articulo, centra su atencion en la aplicacion del analisis modal para evaluar el comportamiento dinamico de un SEP ante la ocurrencia de disturbios de magnitud pequena para diferentes topologias y condiciones de operacion. Los resultados reportados indican, que la aplicacion del analisis modal permite la identificacion directa de las causas que contribuyen en forma negativa al amortiguamiento asociado con los modos electromecanicos, asi como la ubicacion mas adecuada de controles que contribuyan a mejorar el amortiguamiento de los mismos.

  10. Pinch-off of rods by bulk diffusion

    International Nuclear Information System (INIS)

    The morphology of a rod embedded in a matrix undergoing pinching by interfacial-energy-driven bulk diffusion is determined near the point of pinching. We find a self-similar solution that gives a unique temporal power law and interfacial shape prior to pinching and self-similar solutions after pinching. The theory is compared to experiments that employ in situ four-dimensional X-ray tomographic microscopy for rods of liquid or solid pinching by solute diffusion in the high-diffusivity liquid phase. The excellent agreement between experiment and theory confirms that the interfacial morphology near the singularity is universal both before and after pinching; the shape holds regardless of the material system and initial condition. This also implies that the predictions of the time-dependence of the process can be used to determine the time to pinching for a wide variety of physical systems, and thus provide estimates of the time required for capillarity-driven break-up of microstructures from the detachment of secondary dendrite arms to polymer blends.

  11. Progress on z-pinch inertial fusion energy

    International Nuclear Information System (INIS)

    The goal of z-pinch inertial fusion energy (IFE) is to extend the single-shot z-pinch inertial confinement fusion (ICF) results on Z to a repetitive-shot z-pinch power plant concept for the economical production of electricity. Z produces up to 1.8 MJ of x-rays at powers as high as 230 TW. Recent target experiments on Z have demonstrated capsule implosion convergence ratios of 14-21 with a double-pinch driven target, and DD neutron yields up to 8x10exp10 with a dynamic hohlraum target. For z-pinch IFE, a power plant concept is discussed that uses high-yield IFE targets (3 GJ) with a low rep-rate per chamber (0.1 Hz). The concept includes a repetitive driver at 0.1 Hz, a Recyclable Transmission Line (RTL) to connect the driver to the target, high-yield targets, and a thick-liquid wall chamber. Recent funding by a U.S. Congressional initiative for $4M for FY04 is supporting research on RTLs, repetitive pulsed power drivers, shock mitigation, full RTL cycle planned experiments, high-yield IFE targets, and z-pinch power plant technologies. Recent results of research in all of these areas are discussed, and a Road Map for Z-Pinch IFE is presented. (author)

  12. Progress on Z-pinch inertial fusion energy

    International Nuclear Information System (INIS)

    Full text: The goal of z-pinch IFE is to extend the single-shot z-pinch ICF results on Z to a repetitive shot z-pinch power plant concept for energy. Z produces up to 1.8 MJ of x-rays at powers as high as 230 TW. Results of recent target experiments on Z are discussed, including capsule implosion convergence ratios of 14-21 with a double-pinch driven target, and DD neutron yields up to 8 x 1010 with a dynamic hohlraum target. For z-pinch IFE, a power plant concept is discussed that uses high-yield targets (3 GJ) with a low rep-rate per chamber (0.1 Hz). The concept includes a repetitive driver at 0.1 Hz, a Recyclable Transmission Line (RTL) to connect the driver to the target, high-yield targets, and a thick-liquid wall chamber. Recent results on z-pinch IFE research on RTLs, repetitive drivers, shock mitigation, full RTL cycle planned experiments, high-yield IFE targets, and z-pinch power plant technologies are discussed. (author)

  13. Progress in Z-pinch inertial fusion energy.

    Energy Technology Data Exchange (ETDEWEB)

    Weed, John Woodruff

    2010-03-01

    The goal of z-pinch inertial fusion energy (IFE) is to extend the single-shot z-pinch inertial confinement fusion (ICF) results on Z to a repetitive-shot z-pinch power plant concept for the economical production of electricity. Z produces up to 1.8 MJ of x-rays at powers as high as 230 TW. Recent target experiments on Z have demonstrated capsule implosion convergence ratios of 14-21 with a double-pinch driven target, and DD neutron yields up to 8x10exp10 with a dynamic hohlraum target. For z-pinch IFE, a power plant concept is discussed that uses high-yield IFE targets (3 GJ) with a low rep-rate per chamber (0.1 Hz). The concept includes a repetitive driver at 0.1 Hz, a Recyclable Transmission Line (RTL) to connect the driver to the target, high-yield targets, and a thick-liquid wall chamber. Recent funding by a U.S. Congressional initiative for $4M for FY04 is supporting research on RTLs, repetitive pulsed power drivers, shock mitigation, full RTL cycle planned experiments, high-yield IFE targets, and z-pinch power plant technologies. Recent results of research in all of these areas are discussed, and a Road Map for Z-Pinch IFE is presented.

  14. Optimum pinch grips in the handling of dies.

    Science.gov (United States)

    Heffernan, C; Freivalds, A

    2000-08-01

    Handling roller-press dies has caused numerous work-related musculoskeletal disorders in the leather industry. The dies are quite large (0.61 x 0.30 m), heavy (3.5 kg) and are difficult to handle because of the large pinch span requirements (up to 16 cm). The purpose of this study was to determine the optimum pinch span and optimum crossbar angulation to minimize die handling forces. Five-finger pulp-pinch forces were measured on five males and five females with a force-sensitive-resistor instrumented glove while handling a simulated adjustable die. Maximum pinch forces occurred at pinch spans between 1.27 and 3.81 cm, with average female strengths being 57% of average male pinch strengths. Minimum pinch forces to hold the die occurred at a 45 degrees angulation and increased linearly as the angle approached 90 degrees or the normal vertical orientation. The simplest solution to redesigning the dies is to: (1) decrease the distance between the braces to less than 4 cm and (2) slant the braces at 45 degrees. PMID:10975667

  15. Progress on Z-pinch inertial fusion energy.

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Craig Lee

    2004-09-01

    The goal of z-pinch inertial fusion energy (IFE) is to extend the single-shot z-pinch inertial confinement fusion (ICF) results on Z to a repetitive-shot z-pinch power plant concept for the economical production of electricity. Z produces up to 1.8 MJ of x-rays at powers as high as 230 TW. Recent target experiments on Z have demonstrated capsule implosion convergence ratios of 14-21 with a double-pinch driven target, and DD neutron yields up to 8x10exp10 with a dynamic hohlraum target. For z-pinch IFE, a power plant concept is discussed that uses high-yield IFE targets (3 GJ) with a low rep-rate per chamber (0.1 Hz). The concept includes a repetitive driver at 0.1 Hz, a Recyclable Transmission Line (RTL) to connect the driver to the target, high-yield targets, and a thick-liquid wall chamber. Recent funding by a U.S. Congressional initiative for $4M for FY04 is supporting research on RTLs, repetitive pulsed power drivers, shock mitigation, full RTL cycle planned experiments, high-yield IFE targets, and z-pinch power plant technologies. Recent results of research in all of these areas are discussed, and a Road Map for Z-Pinch IFE is presented.

  16. Application of X-Pinch Plasma as X Ray Source for Backlighting High Density Z-Pinch Plasma

    International Nuclear Information System (INIS)

    The characteristics of X ray emission from an X-pinch powered by pulsed power generator PPG-1 (400kA, 100 ns) were investigated with photoconducting detectors (PCDs) and pinhole camera. It was shown that the X-pinch is an intensive and subnanosecond-pulse X ray point source that is very suitable to be used as X ray source for backlighting of wire-array Z- pinch plasma. The evolution of two-wire Z-pinch plasma in its initial stage was ''viewed'' by X ray backlighting method using PPG-1 X-pinch as X ray source. The backlighting images show clearly that all the processes are similar to those occurring in the initial stages of a cylindrical wire-array Z-pinch, including the electric explosion of single wires characterized by the dense wire cores surrounded by the low-density coronal plasma, the expansion of the exploding wire, the sausage instability (m=0) in the coronal plasma around each wire, the motion of the coronal plasma as well as the wire core toward to the symmetrical axis, the formation of the precursor plasma column with a twist structure something like that of higher mode instability, especially the kink instability (m=1). The quantitative measurement of mass density in the plasma around Z-pinch wires was performed based on a step-wedges having known thickness. The mass ablation rate and expansion rate of wire core were obtained. For the purpose of using X-pinch as X ray source for phase-contrast imaging of small and soft biological object, a movable table-top X-pinch device (2m x 1m x 1.5m) was constructed and tested. It was shown that the X ray emission from the X-pinch was observed even with a current as low as 60 kA when thinner wires were used as X-pinch load. The characteristics of the X ray emission from the table-top X-pinch are similar to those from PPG-1 X-pinch. (author)

  17. Theoretical z -pinch scaling relations for thermonuclear-fusion experiments.

    Science.gov (United States)

    Stygar, W A; Cuneo, M E; Vesey, R A; Ives, H C; Mazarakis, M G; Chandler, G A; Fehl, D L; Leeper, R J; Matzen, M K; McDaniel, D H; McGurn, J S; McKenney, J L; Muron, D J; Olson, C L; Porter, J L; Ramirez, J J; Seamen, J F; Speas, C S; Spielman, R B; Struve, K W; Torres, J A; Waisman, E M; Wagoner, T C; Gilliland, T L

    2005-08-01

    We have developed wire-array z -pinch scaling relations for plasma-physics and inertial-confinement-fusion (ICF) experiments. The relations can be applied to the design of z -pinch accelerators for high-fusion-yield (approximately 0.4 GJ/shot) and inertial-fusion-energy (approximately 3 GJ/shot) research. We find that (delta(a)/delta(RT)) proportional (m/l)1/4 (Rgamma)(-1/2), where delta(a) is the imploding-sheath thickness of a wire-ablation-dominated pinch, delta(RT) is the sheath thickness of a Rayleigh-Taylor-dominated pinch, m is the total wire-array mass, l is the axial length of the array, R is the initial array radius, and gamma is a dimensionless functional of the shape of the current pulse that drives the pinch implosion. When the product Rgamma is held constant the sheath thickness is, at sufficiently large values of m/l, determined primarily by wire ablation. For an ablation-dominated pinch, we estimate that the peak radiated x-ray power P(r) proportional (I/tau(i))(3/2)Rlphigamma, where I is the peak pinch current, tau(i) is the pinch implosion time, and phi is a dimensionless functional of the current-pulse shape. This scaling relation is consistent with experiment when 13 MA fusion scale as tau(i)0.36 and tau(i)1.36, respectively. Thus the accelerator requirements decrease as the implosion time is decreased. However, the x-ray-power and thermonuclear-yield efficiencies of such a coupled system increase with tau(i). We also find that increasing the anode-cathode gap of the pinch from 2 to 4 mm increases the requisite values of P(a) and E(a) by as much as a factor of 2. PMID:16196715

  18. Kajian Bentuk Pengolahan dan Analisis Finansial Buah Api api (Avicennia officinalis L.) Sebagai Bahan Makanan dan Minuman di Kabupaten Deli Serdang

    OpenAIRE

    Sianturi, Gustinaria

    2013-01-01

    Penelitian ini bertujuan untuk mengidentifikasi bentuk pengolahan, tingkat kelayakan nilai finansial, dan strategi pengembangan usaha pengolahan buah api-api (Avicennia officinalis L.) di Dusun Paluh Merbau, Desa Tanjung Rejo, Kecamatan Percut Sei Tuan, Kabupaten Deli Serdang. Metode analisis yang digunakan adalah analisis deskriptif, analisis finansial, dan analisis strategi pengembangan usaha dengan menggunakan analisis SWOT. Hasil penelitian menunjukkan bahwa produk olahan buah api-...

  19. Experiments with a fully toroidal Extrap Z-pinch

    International Nuclear Information System (INIS)

    In the Extrap plasma confinement scheme, a Z-pinch is produced along the null of an octupole field generated by currents in external conductors. In the paper, studies of the discharge startup process in a fully toroidal configuration are described. Startup involves first breaking down a toroidal discharge and then driving up the current in order to reach the pinch parameter regime. Current densities of 2x106 A·m-2 have been achieved. The estimated plasma density is 6x1020m-3, and the temperature is about 4 eV. These parameters correspond to pinch conditions. (author)

  20. Thermonuclear Fusion with the Sheared Flow Stabilized Z-Pinch

    OpenAIRE

    Winterberg, F.; Wanex, L. F.

    2008-01-01

    Two basic approaches to producing thermonuclear fusion with a sheared flow stabilized z-pinch are considered. One consists of heating the entire length of the z-pinch column to the required temperatures. The other basic approach considered here involves the concept of fast ignition. A localized "hot-spot" is produced under the proper conditions to ignite a thermonuclear burn wave in the z-pinch plasma. Here we demonstrate that sheared flow stabilization is more efficient in the fast-ignition ...

  1. Design of magnetic mirrors for a linear theta pinch

    International Nuclear Information System (INIS)

    The problem of generating optimum magnetic mirror fields at the ends of a 50-cm long theta-pinch experiment to study particle flow and loss effects has been investigated. A combination of active and passive mirrors was developed to produce 2-3:1 fields for a 23-kG pinch. Biot-Savart and potential field prediction solutions for the magnetic field distribution were compared with experimental measurements in 2-5-cm long coils for the 50-cm long pinch

  2. Laser beam plasma pinch x-ray system

    International Nuclear Information System (INIS)

    A system is provided for producing plasma pinch X-rays usable in X-ray lithography. Ionized heated plasma vapor is repeatably generated directly from solid material by impingement of a plurality of circumferentially spaced laser beams to generate an annulus of plasma. X-rays are generated by passing high current through the annular plasma in an axial gap between the solid material target electrode and another electrode, causing magnetic field radial inward plasma pinching to a central constricted area further heating the plasma and emitting X-rays. A central axially directed laser may further heat the plasma in the pinched area

  3. EL DERECHO A LA INTEGRIDAD PERSONAL -ELEMENTOS PARA SU ANALISIS

    Directory of Open Access Journals (Sweden)

    María Isabel Afanador C.

    2002-01-01

    Full Text Available El presente ensayo se ocupa del estudio de los elementos esenciales del derecho a la integridad personal, desde la evolución histórica y normativa de su reconocimiento, así como del análisis crítico respecto de las más graves manifestaciones de su violación, tales como la tortura y la desaparición forzada de personas. El escrito está centrado no sólo en la fundamentación jurídica del tema, desde la perspectiva del Derecho Internacional de los Derechos Humanos (DIDH, sino que comprende el análisis político de la realidad colombiana en esta materia, en el contexto de una concepción democrática de los derechos humanos, sin negar que el problema pueda ser abordado y discutido desde otras perspectivas.

  4. Desain Dan Analisis Perhitungan Roda Pendaratan Pesawat Tanpa Awak

    OpenAIRE

    Aulia, T. Muhammad Rinaldi

    2015-01-01

    Landing gear merupakan struktur pesawat yang berfungsi menahan beban statis pesawat dan juga beban dinamis ketika pesawat melakukan pendaratan. Dalam mendesain landing gear dilakukan pemilihan jenis landing gear dan dilakukan analisis perhitungan pada tiap komponen landing gear yang meliputi pusat gravitasi, tinggi pesawat, wheel base, wheel track, dan roda. Desain dan analisis perhitungan dilakukan dengan metode studi pustaka dimana setiap desain dan perhitungan didasarkan pada literatur pu...

  5. Nasionalisme dalam Novel 5 cm. Karya Donny Dhirgantoro: Analisis Strukturalisme

    OpenAIRE

    Ichwan, Yasir

    2014-01-01

    Penelitian ini menganalisis tentang struktur yang membangun nilai nasionalisme dan bentuk nasionalisme dalam novel 5 cm. karya Donny Dhirgantoro. Adapun tujuan penelitian ini adalah untuk memahami makna nasionalisme secara lebih luas. Metode pengumpulan data yang dilakukan peneliti adalah teknik pustaka, baca, dan catat. Teknik analisis data yang dilakukan peneliti adalah menganalisis unsur-unsur pembangun novel, mengaitkan antara unsur pembangun novel, menyajikan hasil analisis, dan menyimpu...

  6. Analisis Dan Strategi Pengembangan Nilai Tambah Produk Perikanan (Studi Kasus: Kecamatan Teluk Mengkudu, Kabupaten Serdang Bedagai)

    OpenAIRE

    Ramadani, Rizki

    2015-01-01

    Daerah penelitian ditentukan secara sengaja (purposive) berdasarkan pertimbangan tertentu. Penarikan sampel dilakukan dengan Metode Sensus, yaitu keseluruhan populasi diambil sebagai sampel dikarenakan jumlah populasi hanya sedikit yaitu berjumlah 16 pengusaha pengolahan ikan asin. Metode analisis yang digunakan adalah Analisis Nilai Tambah Metode Hayami dan Analisis SWOT. Hasil penelitian menunjukkan bahwa nilai tambah yang diperoleh pengusaha dalam pengolahan ikan asin sebe...

  7. Alfven wave heating of a theta pinch

    International Nuclear Information System (INIS)

    The process of shear Alfven wave resonant absorption for plasma heating has been applied to a theta pinch. The m=1 mode is excited by means of a helical launching structure with a given wavelength, at a number of different frequencies. When the frequency lies in the continuous Alfven spectrum the kink energy is transferred to the Alfven wave and then is rapidly thermalized. The heating power is measured by a diamagnetic probe. It is shown that the probe signal can be treated as a thermodynamic variable permitting an exact energy balance to be deduced. The measured resonance curve of the heating power is in agreement with the predicted behaviour. A 50% efficiency is achieved and the coupling between the plasma and the external circuit is strong, in spite of the high compression ratio. (author)

  8. The interrupted Z-pinch dynamics modeling

    International Nuclear Information System (INIS)

    The Z-pinch has been formed in the discharge between two cone-shaped copper electrodes (top angle 90o and diameter 10 mm each, interelectrode distance 10 mm) placed in a glass vacuum chamber filled with the air under the pressure 5kPa. The used energy source - 3 μF condenser battery - was charged to a voltage of 18 kV and the discharge current reached its maximum 50 kA at a time 1 μs after the breakdown. The discharge was studied by the Michelson interferometry and Schlieren methods. The Michelson interferometry enabled to average the electron density calculations under the assumption of Z-pinch cylindrical geometry. The Schlieren method with variable diameter of the focal point disk screen was used to study the small scale concentration gradients in the filaments of the discharge. Both methods, the Michelson interferometry and the Schlieren method, comprise a ruby laser switched in the Q-regime as the light source. The laser light pulse duration was 0.04 μs. Due to the synchronization and the delay of the light pulse from the discharge ignition, there was a possibility to get a series of experiments. The experiments were carried out every 0.1 μs during the 1 μs time interval after the discharge ignition, the results were registered with a camera. During every discharge there was taken one snap only, but the sequence of measurements was very well acceptable for the discharge evolution study due to the discharge good repeatability (25% variance about a mean). (author) 2 refs., 5 figs

  9. Nonlocal transport in the reversed field pinch

    International Nuclear Information System (INIS)

    Several heuristic models for nonlocal transport in plasmas have been developed, but they have had a limited possibility of detailed comparison with experimental data. Nonlocal aspects introduced by the existence of a known spectrum of relatively stable saturated tearing modes in a low current reversed field pinch (RFP) offers a unique possibility for such a study. A numerical modeling of the magnetic structure and associated particle transport is carried out for the RFP experiment at the Consorzio RFX, Padova, Italy. A reproduction of the tearing mode spectrum with a guiding center code (White and Chance 1984 Phys. Fluids 27 2455) reliably reproduces the observed soft x-ray tomography. Following particle trajectories in the stochastic magnetic field shows the transport across the unperturbed flux surfaces to be due to a spectrum of Levy flights, with the details of the spectrum position dependent. The resulting transport is subdiffusive, and cannot be described by Rechester-Rosenbluth diffusion, which depends on a random phase approximation. If one attempts to fit the local transport phenomenologically, the subdiffusion can be fit with a combination of diffusion and inward pinch (Spizzo et al 2007 Phys. Plasmas 14 102310). It is found that whereas passing particles explore the stochastic field and hence participate in Levy flights, the trapped particles experience normal neoclassical diffusion. A two fluid nonlocal Montroll equation is used to model this transport, with a Levy flight defined as the motion of an ion during the period that the pitch has one sign. The necessary input to the Montroll equation consists of a time distribution for the Levy flights, given by the pitch angle scattering operator, and a distribution of the flight distances, determined numerically using a guiding center code. Results are compared with the experiment. The relation of this formulation to fractional kinetics is also described.

  10. Z-pinch driven fusion energy

    International Nuclear Information System (INIS)

    The Z machine at Sandia National Laboratories (SNL) is the most powerful multi-module synchronized pulsed-power accelerator in the world. Rapid development of z-pinch loads on Z has led to outstanding progress in the last few years, resulting in radiative powers of up to 280 TW in 4 ns and a total radiated x-ray energy of 1.8 MJ. The present goal is to demonstrate single-shot, high-yield fusion capsules. Pulsed power is a robust and inexpensive technology, which should be well suited for Inertial Fusion Energy, but a rep-rated capability is needed. Recent developments have led to a viable conceptual approach for a rep-rated z-pinch power plant for IFE. This concept exploits the advantages of going to high yield (a few GJ) at low rep-rate (approximately 0.1 Hz), and using a Recyclable Transmission Line (RTL) to provide the necessary standoff between the fusion target and the power plant chamber. In this approach, a portion of the transmission line near the capsule is replaced after each shot. The RTL should be constructed of materials that can easily be separated from the liquid coolant stream and refabricated for a subsequent shots. One possibility is that most of the RTL is formed by casting FLiBe, a salt composed of fluorine, lithium, and beryllium, which is an attractive choice for the reactor coolant, with chemically compatible lead or tin on the surface to provide conductivity. The authors estimate that fusion yields greater than 1 GJ will be required for efficient generation of electricity. Calculations indicate that the first wall will have an acceptable lifetime with these high yields if blast mitigation techniques are used. Furthermore, yields above 5 GJ may allow the use of a compact blanket direct conversion scheme

  11. Z-pinch driven fusion energy

    Energy Technology Data Exchange (ETDEWEB)

    SLUTZ,STEPHEN A.; OLSON,CRAIG L.; ROCHAU,GARY E.; DERZON,MARK S.; PETERSON,P.F.; DEGROOT,J.S.; JENSEN,N.; MILLER,G.

    2000-05-30

    The Z machine at Sandia National Laboratories (SNL) is the most powerful multi-module synchronized pulsed-power accelerator in the world. Rapid development of z-pinch loads on Z has led to outstanding progress in the last few years, resulting in radiative powers of up to 280 TW in 4 ns and a total radiated x-ray energy of 1.8 MJ. The present goal is to demonstrate single-shot, high-yield fusion capsules. Pulsed power is a robust and inexpensive technology, which should be well suited for Inertial Fusion Energy, but a rep-rated capability is needed. Recent developments have led to a viable conceptual approach for a rep-rated z-pinch power plant for IFE. This concept exploits the advantages of going to high yield (a few GJ) at low rep-rate ({approximately} 0.1 Hz), and using a Recyclable Transmission Line (RTL) to provide the necessary standoff between the fusion target and the power plant chamber. In this approach, a portion of the transmission line near the capsule is replaced after each shot. The RTL should be constructed of materials that can easily be separated from the liquid coolant stream and refabricated for a subsequent shots. One possibility is that most of the RTL is formed by casting FLiBe, a salt composed of fluorine, lithium, and beryllium, which is an attractive choice for the reactor coolant, with chemically compatible lead or tin on the surface to provide conductivity. The authors estimate that fusion yields greater than 1 GJ will be required for efficient generation of electricity. Calculations indicate that the first wall will have an acceptable lifetime with these high yields if blast mitigation techniques are used. Furthermore, yields above 5 GJ may allow the use of a compact blanket direct conversion scheme.

  12. Sawteeth in the MST reversed field pinch

    International Nuclear Information System (INIS)

    A dynamo mechanism has been used in astrophysics to explain the self-generation of the magnetic fields observed throughout the universe. This same type of phenomenon is believed to occur in the reversed field pinch (RFP) plasmas. The RFP dynamo has been a major theoretical and experimental investigation since the first observations of the self-reversal process in early pinch research. A discrete dynamo event has been observed in the experimental RFP plasmas; this event is termed the RFP sawtooth. This phenomenon is similar to the sawtooth phenomenon observed in tokamak plasmas, but the two events differ in many respects. Both events are a result of the inward diffusion of the plasma current density. This causes the plasma to become unstable to the m = 1 tearing modes. It has been shown theoretically that the nonlinear interaction of these modes can generate the reversed toroidal field in the RFP. This thesis is a study of the RFP sawtooth phenomenon on the MST RFP. This includes experimental observations as well as 1-D numerical simulations of the sawtooth rise-time. During the rise-time of the sawtooth, the plasma is undergoing a purely diffusive process -- no dynamo is occurring during this phase. The dynamo only occurs during the sawtooth crash. During the rise-time, the m = 1 modes are observed to grow, and nonlinear interactions are observed prior to the sawtooth crash. At the time of the crash, many of the plasma profiles are flattened; these include the current density, the plasma temperature and the plasma density. The period of the sawteeth is observed to increase with the plasma current, as well as the magnetic Reynolds number, S

  13. Turbulent equipartition pinch of toroidal momentum in spherical torus

    International Nuclear Information System (INIS)

    We present a new analytic expression for turbulent equipartition (TEP) pinch of toroidal angular momentum originating from magnetic field inhomogeneity of spherical torus (ST) plasmas. Starting from a conservative modern nonlinear gyrokinetic equation (Hahm et al 1988 Phys. Fluids 31 2670), we derive an expression for pinch to momentum diffusivity ratio without using a usual tokamak approximation of B ∝ 1/R which has been previously employed for TEP momentum pinch derivation in tokamaks (Hahm et al 2007 Phys. Plasmas 14 072302). Our new formula is evaluated for model equilibria of National Spherical Torus eXperiment (NSTX) (Ono et al 2001 Nucl. Fusion 41 1435) and Versatile Experiment Spherical Torus (VEST) (Chung et al 2013 Plasma Sci. Technol. 15 244) plasmas. Our result predicts stronger inward pinch for both cases, as compared to the prediction based on the tokamak formula. (paper)

  14. The TITAN reversed-field-pinch fusion reactor study

    International Nuclear Information System (INIS)

    This paper on titan plasma engineering contains papers on the following topics: reversed-field pinch as a fusion reactor; parametric systems studies; magnetics; burning-plasma simulations; plasma transient operations; current drive; and physics issues for compact RFP reactors

  15. A Z-Pinch Driven Fusion Reactor Concept

    Science.gov (United States)

    Derzon, Mark; Rochau, Gregory; Spielman, Rick; Slutz, Stephen; Rochau, G. E.; Peterson, R. R.; Peterson, P. F.

    1999-11-01

    Recent z-pinch target physics progress has encouraged us to consider how a power reactor could be configured based on a fast z-pinch driver. Initial cost estimates show that recyclable transmission lines (RTLs) are economically viable. Providing 'standoff' between the primary power supply and the target, which is what disposable RTLs provide, has historically been the main obstacle to the consideration of pinches as fusion drivers. We will be introducing basic reactor scaling in terms of shot rate, yield, tritium breeding and neutron flux, etc. This concept has advantages in that z-pinches provide a robust mechanical environment, as well as a chamber which does not require low-pressure pumping between shots and the wall lifetime is expected to be limited factors other than neutron damage. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000.

  16. Impact of PINCH expression on survival in colorectal cancer patients

    International Nuclear Information System (INIS)

    The adaptor protein PINCH is overexpressed in the stroma of several types of cancer, and is an independent prognostic marker in colorectal cancer. In this study we further investigate the relationship of PINCH and survival regarding the response to chemotherapy in colorectal cancer. Paraffin-embedded tissue sections from 251 primary adenocarcinomas, 149 samples of adjacent normal mucosa, 57 samples of distant normal mucosa and 75 lymph node metastases were used for immunohistochemical staining. Stromal staining for PINCH increased from normal mucosa to primary tumour to metastasis. Strong staining in adjacent normal mucosa was related to worse survival independently of sex, age, tumour location, differentiation and stage (p = 0.044, HR, 1.60, 95% CI, 1.01-2.52). PINCH staining at the invasive margin tended to be related to survival (p = 0.051). In poorly differentiated tumours PINCH staining at the invasive margin was related to survival independently of sex, age and stage (p = 0.013, HR, 1.90, 95% CI, 1.14-3.16), while in better differentiated tumours it was not. In patients with weak staining, adjuvant chemotherapy was related to survival (p = 0.010, 0.013 and 0.013 in entire tumour area, invasive margin and inner tumour area, respectively), but not in patients with strong staining. However, in the multivariate analysis no such relationship was seen. PINCH staining in normal adjacent mucosa was related to survival. Further, PINCH staining at the tumour invasive margin was related to survival in poorly differentiated tumours but not in better differentiated tumours, indicating that the impact of PINCH on prognosis was dependent on differentiation status

  17. The ZaP Flow Z-Pinch Project

    International Nuclear Information System (INIS)

    The results from the ZaP experiment are consistent with the theoretical predictions of sheared flow stabilization. Z pinches with a sheared flow are generated in the ZaP experiment using a coaxial accelerator coupled to an assembly region. The current sheet in the accelerator initially acts as a snowplow. As the Z pinch forms, plasma formation in the accelerator transits to a deflagration process. The plasma exits the accelerator and maintains the flow in the Z pinch. During the quiescent period in the magnetic mode activity at z=0 cm, a stable Z pinch is seen on the axis of the assembly region. The evolution of the axial velocity profile shows a large velocity shear is measured at the edge of the Z pinch during the quiescent period. The velocity shear is above the theoretical threshold. As the velocity shear decreases towards 0.1kVA, the predicted stability threshold, the quiescent period ends. The present understanding of the ZaP experiment shows that it may be possible for the Z pinch to operate in a steady state if the deflagration process can be maintained by constantly supplying neutral gas or plasma to the accelerator

  18. Sausage mode of a high density Z-pinch

    International Nuclear Information System (INIS)

    In Z-pinch experiments at Maxwell Laboratories, Inc., growth rates have been measured by observing optical emission along the pinch axis. Growth rates estimated by means of the usual model of a pinch involving an incompressible fluid and a surface current are too large by a factor of 2-4. X-ray pinhole photographs generally have the appearance of a series of beads that would be expected from instability of the sausage mode. In some cases, particularly the implosion of large diameter wire arrays with BLACKJACK 5, the beads disappear and only the kink instability is apparent. Generalizing the pinch model to include compressibility does not significantly alter the predictions. A further generalization to include distributed current has therefore been considered. It seems likely that the current can penetrate significantly during the lifetime of the pinch. We consider a model of the pinch that is initially an infinite cylinder. For the sausage mode, stability is determined by a simple second order differential equation together with the boundary condition that follows from the wave number and the frequency of the instability

  19. Experiments on screw-pinch plasmas with elongated cross section

    International Nuclear Information System (INIS)

    In this thesis experiments are described carried out with SPICA II, a toroidal screw-pinch plasma device. this device is the last one in a series of plasma machines of the toroidal screw-pinch differing from its predecessor in its race-track shaped section. In devices of the type toroidal screw-pinch stable confinement is possible of plasmas with larger β values than in a tokamak discharge. In a pinch the plasma is screwed up, during the formation, in such a way that in a relatively small volume a plasma is formated with a high pressure. During the screwing up the plasma is heated by shock heating as well as adiabatic compression. With the modified snowplow model the density and temperature after the formation can be calculated, starting from the initial conditions. When all ions arrive into the plasma column, the density in the column is determined by the volume compression. First purpose of the experiments was to find a stable discharge. Subsequently discharges have been made with a high as possible β in order to investigate at which maximum β it is possible to confine screw-pinch plasmas stably. When these had been found, the nature and importance could be investigated of the processes following which the screw-pinch plasma looses its energy. (author), 75 res.; 95 figs.; 8 tabs

  20. Z-Pinch Pulsed Plasma Propulsion Technology Development

    Science.gov (United States)

    Polsgrove, Tara; Adams, Robert B.; Fabisinski, Leo; Fincher, Sharon; Maples, C. Dauphne; Miernik, Janie; Percy, Tom; Statham, Geoff; Turner, Matt; Cassibry, Jason; Cortez, Ross; Santarius, John

    2010-01-01

    Fusion-based propulsion can enable fast interplanetary transportation. Magneto-inertial fusion (MIF) is an approach which has been shown to potentially lead to a low cost, small reactor for fusion break even. The Z-Pinch/dense plasma focus method is an MIF concept in which a column of gas is compressed to thermonuclear conditions by an axial current (I approximates 100 MA). Recent advancements in experiments and the theoretical understanding of this concept suggest favorable scaling of fusion power output yield as I(sup 4). This document presents a conceptual design of a Z-Pinch fusion propulsion system and a vehicle for human exploration. The purpose of this study is to apply Z-Pinch fusion principles to the design of a propulsion system for an interplanetary spacecraft. This study took four steps in service of that objective; these steps are identified below. 1. Z-Pinch Modeling and Analysis: There is a wealth of literature characterizing Z-Pinch physics and existing Z-Pinch physics models. In order to be useful in engineering analysis, simplified Z-Pinch fusion thermodynamic models are required to give propulsion engineers the quantity of plasma, plasma temperature, rate of expansion, etc. The study team developed these models in this study. 2. Propulsion Modeling and Analysis: While the Z-Pinch models characterize the fusion process itself, propulsion models calculate the parameters that characterize the propulsion system (thrust, specific impulse, etc.) The study team developed a Z-Pinch propulsion model and used it to determine the best values for pulse rate, amount of propellant per pulse, and mixture ratio of the D-T and liner materials as well as the resulting thrust and specific impulse of the system. 3. Mission Analysis: Several potential missions were studied. Trajectory analysis using data from the propulsion model was used to determine the duration of the propulsion burns, the amount of propellant expended to complete each mission considered. 4

  1. Historical-statistical analysis of energy consumption in energy management; Analisis historico-estadistico del consumo energetico en la administracion de energia

    Energy Technology Data Exchange (ETDEWEB)

    Guizar Bejarano, Ruben [IMENOR (Mexico); Oven, Mark [RCG/Hagler, Bailly, Inc., Washington (United States)

    1992-12-31

    Traditionally the specific consumption of energy has been considered as the most adequate index to evaluate the efficiencies in the productive processes. Nevertheless, this index, in some instances is highly susceptible to suffer significant variations, due to factors such as equipment condition, raw materials quality, operational parameters, climate and production level. This last one definitely is the most important and requires a deeper analysis. In this presentation a methodology is developed to analyze the energy consumption as well as their specific energy consumption with respect to production. Enough historical data are utilized to allow for a statistical analysis. This study is of equal usefulness in an energy diagnosis, as in a management program of energy saving. In presenting the possibility of identifying potential energy saving, stands out the advantages of the analysis and the conclusions that can be derived from it. Through the actual data collected in several industries during the energy diagnosis, various possible results of the analysis are presented. Finally, how this type of analysis can be adapted to a more precise control of the energy consumption is described and be used as a base for establishing goals in energy efficiency in the long term. [Espanol] Tradicionalmente se ha considerado al consumo especifico de energia como el indice energetico mas adecuado para evaluar las eficiencias de los procesos productivos. Sin embargo, este indice es en ocasiones altamente susceptible a sufrir variaciones importantes, debido a factores como el estado de los equipos, la calidad de la materia prima, los parametros operativos, el clima, y el nivel de produccion. Este ultimo es decididamente el mas importante, y requiere un analisis mas profundo. En esta presentacion se desarrolla una metodologia para analizar tanto consumos de energia como consumos especificos de energia con respecto a la produccion. Se utilizan suficientes datos historicos para permitir

  2. Entropy generation reduction through chemical pinch analysis

    International Nuclear Information System (INIS)

    The pinch analysis (PA) concept emerged, late '80s, as one of the methods to address the energy management in the new era of sustainable development. It was derived from combined first and second law analysis, as a technique ensuring a better thermal integration, aiming the minimization of entropy production or, equivalently, exergy destruction by heat exchanger networks (HEN). Although its ascendance from the second law analysis is questionable, the PA reveals as a widespread tool, nowadays, helping in energy savings mostly through a more rational use of utilities. Unfortunately, as principal downside, one should be aware that the global minimum entropy production is seldom attained, since the PA does not tackle the whole plant letting aside the chemical reactors or separation trains. The chemical reactor network (CRN) is responsible for large amounts of entropy generation (exergy losses), mainly due to the combined composition and temperature change. The chemical pinch analysis (CPA) concept focuses on, simultaneously, the entropy generation reduction of both CRN and HEN, while keeping the state and working parameters of the plant in the range of industrial interest. The fundamental idea of CPA is to include the CRN (through the chemical reaction heat developed in reactors) into the HEN and to submit this extended system to the PA. This is accomplished by replacing the chemical reactor with a virtual heat exchanger system producing the same amount of entropy. For an endothermic non-adiabatic chemical reactor, the (stepwise infinitesimal) supply heat δq flows from a source (an external/internal heater) to the stream undergoing the chemical transformation through the reactor, which in turn releases the heat of reaction ΔHR to a virtual cold stream flowing through a virtual cooler. For an exothermic non-adiabatic chemical reactor, the replacement is likewise, but the heat flows oppositely. Thus, in the practice of designing or retrofitting a flowsheet, in order to

  3. Nonlinear analysis of thermal stresses of a of first stage nozzle of a gas turbine at full load from the results of an analysis of conjugated heat transference; Analisis no lineal de esfuerzos termicos de una tobera de primera etapa de turbina de gas a plena carga a partir de resultados de un analisis de transferencia de calor conjugado

    Energy Technology Data Exchange (ETDEWEB)

    Perez Hernandez, Efrain [Centro Nacional de Investigacion y Desarrollo Tecnologico (Cenidet), Cuernavaca, Morelos (Mexico); Mazur C, Zdzislaw; Garcia Illescas, R; Hernandez Rossette, Alejandro [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2007-11-15

    The gas turbines operate at extremely high temperatures, at high thermal and mechanical stresses, causing that the useful life of the involved components be reduced. In the present article the results realized by previous investigations of temperatures obtained from analysis of heat transfer and flow of fluids of the nozzle by means of the Star-CD program based on finite volumes is presented. Later, the NISA program of finite elements was used to realize the analysis of thermal stresses considering the material plasticity. The methodology employed to determine the material properties variable with the temperature of the super-alloy FSX-414 and the plasticity model used in the structural analysis in the finite element program. The result will be later used in the fatigue analysis for the useful life assessment. [Spanish] Las turbinas de gas operan a temperatura extremadamente altas, a elevados esfuerzos termicos y mecanicos, ocasionando que la vida de los componentes involucrados se reduzca. En el presente articulo se presentan los resultados realizados por previas investigaciones de temperaturas obtenidas a partir de analisis de transferencia de calor y flujo de fluidos de la tobera mediante el programa Star-CD basado en volumenes finitos. Posteriormente, se utilizo el programa NISA de elementos finitos para realizar el analisis de esfuerzos termicos considerando plasticidad del material. Se muestra la metodologia empleada para determinar las propiedades del material variables con la temperatura de la superaleacion FSX-414 y el modelo de plasticidad utilizado en el analisis estructural en el programa de elemento finito. Los resultados seran empleados posteriormente en el analisis de fatiga para la estimacion de vida util.

  4. Progress on Z-pinch inertial fusion energy

    International Nuclear Information System (INIS)

    The long-range goal of the Z-Pinch IFE programme is to produce an economically attractive power plant using high-yield z-pinch-driven targets (∼3 G J) with low rep-rate per chamber (∼0.1 Hz). The present mainline choice for a Z-Pinch IFE power plant uses an LTD (Linear Transformer Driver) repetitive pulsed power driver, a Recyclable Transmission Line (Rl), a dynamic hohlraum z-pinch-driven target, and a thick-liquid wall chamber. The RTL connects the pulsed power driver directly to the z-pinch-driven target, and is made from frozen coolant or a material that is easily separable from the coolant (such as carbon steel). The RTL is destroyed by the fusion explosion, but the RTL materials are recycled, and a new RTL is inserted on each shot. The RTL concept eliminates the problems of a final optic, high-speed target injection, and pointing and tracking N beams (N∼100). Instead, the RTL concept must be shown to be feasible and economically attractive. Results of z-pinch IFE studies over the last three years are discussed, including RTL experiments at the 10 MA level on Saturn, RTL structural studies, RTL manufacturing/cost studies, RTL activation analysis, power plant studies, high-yield IFE target studies, etc. Recent funding by a U.S. Congressional initiative of 4 million dollars for FY04 is supporting research on (1) RTLs, (2) repetitive pulsed power drivers, (3) shock mitigation [because of the high yield targets], (4) planning for a proof-of-principle full RTL cycle demonstration [with a 1 MA, 1 MV, 100 ns, 0.1 Hz driver], (5) IFE target studies for multi-GJ yield targets, and (6) z-pinch IFE power plant engineering and technology development. (author)

  5. Reversed-field pinch fusion reactor

    International Nuclear Information System (INIS)

    A conceptual engineering design of a fusion reactor based on plasma confinement in a toroidal Reversed-Field Pinch (RFP) configuration is described. The plasma is ohmically ignited by toroidal plasma currents which also inherently provide the confining magnetic fields in a toroidal chamber having major and minor radii of 12.7 and 1.5 m, respectively. The DT plasma ignites in 2 to 3 s and undergoes a transient, unrefueled burn at 10 to 20 keV for approx. 20 s to give a DT burnup of approx. 50%. The 5-s dwell period between burn pulses for plasma quench and refueling allows steady-state operation of all thermal systems outside the first wall; no auxiliary thermal capacity is required. Tritium breeding occurs in a granular Li2O blanket which is packed around an array of radially oriented water/steam coolant tubes. The slightly superheated steam emerging from this blanket directly drives a turbine that produces electrical power at an efficiency of 30%. A borated-water shield is located immediately outside the thermal blanket to protect the superconducting magnet coils. Both the superconducting poloidal and toroidal field coils are energized by homopolar motor/generators. Accounting for all major energy sinks yields a cost-optimized system with a recirculating power fraction of 0.17; the power output is 750 MWe

  6. Pinch Me - I'm Fusing

    International Nuclear Information System (INIS)

    The process of combining nuclei (the protons and neutrons inside an atomic nucleus) together with a release of kinetic energy is called fusion. This process powers the Sun, it contributes to the world stockpile of weapons of mass destruction and may one day generate safe, clean electrical power. Understanding the intricacies of fusion power, promised for 50 years, ,is sometimes difficult because there are a number of ways of doing it. There is hot fusion, cold fusion and con-fusion. Hot fusion is what powers suns through the conversion of mass energy to kinetic energy. Cold fusion generates con-fusion and nobody really knows what it is. Honestly - this is true. There does seem to be something going on here; I just don't know what. Apparently some experimenters get energy out of a process many call cold fission but no one seems to know what it is, or how to do it reliably. It is not getting much attention from the mainline physics community. Even so, no one is generating electrical power for you and me with either method. In this article 1 will point out some basic features of the mainstream approaches taken to hot fusion power, as well as describe why z pinches are worth pursuing as a driver for a power reactor and may one day generate electrical power for mankind

  7. Pinch Me - I'm Fusing!

    Energy Technology Data Exchange (ETDEWEB)

    DERZON,MARK S.

    2000-07-19

    The process of combining nuclei (the protons and neutrons inside an atomic nucleus) together with a release of kinetic energy is called fusion. This process powers the Sun, it contributes to the world stockpile of weapons of mass destruction and may one day generate safe, clean electrical power. Understanding the intricacies of fusion power, promised for 50 years, ,is sometimes difficult because there are a number of ways of doing it. There is hot fusion, cold fusion and con-fusion. Hot fusion is what powers suns through the conversion of mass energy to kinetic energy. Cold fusion generates con-fusion and nobody really knows what it is. Honestly - this is true. There does seem to be something going on here; I just don't know what. Apparently some experimenters get energy out of a process many call cold fission but no one seems to know what it is, or how to do it reliably. It is not getting much attention from the mainline physics community. Even so, no one is generating electrical power for you and me with either method. In this article 1 will point out some basic features of the mainstream approaches taken to hot fusion power, as well as describe why z pinches are worth pursuing as a driver for a power reactor and may one day generate electrical power for mankind.

  8. Two Fluid Dynamo in Reversed Field Pinch

    Science.gov (United States)

    Mirnov, V. V.; Hegna, C. C.; Prager, S. C.; Sovinec, C. R.

    2006-10-01

    In the Madison Symmetric Torus reversed field pinch experiments, tearing instabilities are observed to generate magnetic field, flow velocity and current density fluctuations that follow a temporally cyclic sawtooth behavior. One of the consequences of these instabilities is the production of dynamos, fluctuation-induced mean electromotive forces in the generalized Ohm's law, that surge during sawtooth crashes. In two-fluid theories, the dynamo is produced from the combination of the MHD (vxB) and Hall (jxB) contributions to Ohm's law. We report new results on the physics of two-fluid dynamos with particular focus on edge-resonant m=0 tearing modes. The two fluid quasilinear theory that was originally derived for a sheared slab [1] is generalized to cylindrical geometry and illuminates the effects of current gradient and field line curvature. The key results are: (1) two fluid effects are important for dynamo through their influence on the phase between the fluctuations; (2) two-fluid theory yields a non-zero flux surface averaged Hall dynamo that is absent in resistive MHD; (3) the two fluid version of the NIMROD code confirms analytic results during the linear stage of the instability but exhibits significant broadening of the Hall dynamo profile on the longer time scales of nonlinear evolution. *Work supported by the USDoE and NSF. [1]V.V.Mirnov, C.C.Hegna, and S.C.Prager, Plasma Physics Report 29, 612 (2003)

  9. Reversed-Field Pinch Reactor (RFPR) concept

    International Nuclear Information System (INIS)

    A conceptual engineering design of a fusion reactor based on plasma confinement in a Reversed-Field Pinch (FRP) configuration is presented. A 50% atomic mixture of deuterium and tritium (DT) is ohmically heated to ignition by currents flowing in the toroidal plasma; this plasma current also inherently produces the confining magnetic fields in a toroidal chamber having a major and minor radii of 12.7 and 1.5 m, respectively. The DT plasma ignites in 2 to 3 s and burns at 10 to 20 keV for approx. 20 s to give a fuel burnup of approx. 50%. Tritium breeding occurs in a granular Li2O blanket which is packed around an array of radially oriented coolant tubes carrying a mixture of high-pressure steam and water. The slightly superheated steam emerging from this blanket would be used to drive a turbine directly. Low-pressure helium containing trace amounts of oxygen is circulated through the packed Li2O bed to extract the tritium. A 20-mm-thick copper first wall serves as a neutron multiplier, acts as a tritium barrier, and supports image currents to provide plasma stabilization on a 0.1-s timescale; external windings provide stability for longer times

  10. Reversed field pinch reactor study 3

    International Nuclear Information System (INIS)

    This report, the third of a series on the Reversed Field Pinch Reactor, describes a preliminary concept of the engineering design and layout of this pulsed toroidal reactor, which uses the stable plasma behaviour first observed in ZETA. The basic parameters of the 600 MW(e) reactor are taken from a companion study by Hancox and Spears. The plasma volume is 1.75m minor radius and 16m major radius surrounded by a 1.8m blanket-shield region - with the blanket divided into 14 removable segments for servicing. The magnetic confinement system consists of 28 toroidal field coils situated just outside the blanket and inside the poloidal and vertical field coils and all coils have normal copper conductors. The requirement to incorporate a conducting shell at the front of the blanket to provide a short-time plasma stability has a marked effect on the design. It sets the size of the blanket segment and the scale of the servicing operations, limits the breeding gain and complicates the blanket cooling and its integration with the heat engine. An extensive study will be required to confirm the overall reactor potential of the concept. (author)

  11. ANALISIS VARIABEL KEUANGAN YANG MEMPENGARUHI KEBIJAKAN DEVIDEN

    Directory of Open Access Journals (Sweden)

    Sumiadji -

    2012-03-01

    Full Text Available Penelitian ini dilakukan untuk menguji pengaruh variabel keuangan yang terdiri dari: rasio pro-fitabilitas (return on assets, likuiditas (cash ratio, rasio hutang (debt to equity ratio, market value (earnings per share, dan perputaran total aset (total assets turnover terhadap kebijakan dividen yang diproksikan dengan dividend payout ratio (DPR pada perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia tahun 2004-2008. Prosedur pemilihan sampel penelitian menggunakan purposive sampling sehingga menghasilkan 8 perusahaan yang memenuhi kriteria sampel. Data sekunder dikumpulkan dengan teknik dokumentasi bersumber dari Indonesian Capital Market Directory (ICMD, laporan keuangan, dan hasil Rapat Umum Pemegang Saham (RUPS. Teknik analisis yang digunakan dalam penelitian ini adalah analisis regresi linear berganda. Hasil penelitian ini adalah secara simultan variabel ROA, CR, DER, EPS dan TATO berpengaruh terhadap DPR. Secara parsial variabel yang mempengaruhi DPR adalah CR, EPS dan TATO. Varabel lainnya, yaitu ROA dan DER ditemukan tidak berpengaruh terhadap DPR. This research was conducted to examine the influence of the financial variables which consists of: return on assets (ROA, cash ratio (CR, debt to equity ratio (DER, earnings per share (EPS, and total asset turnover (TATO to the dividend policy that indicated by the dividend payout ratio (DPR of listed manufacturing company in Indonesia Stock Exchange  2004 to 2008. The sample selection procedure used was a purposive sampling so that it produced eight companies that met the sample criteria. Se-condary data was collected by the documentation technique were obtained from the Indonesian Capital Market Directory (ICMD, financial statements, and the results of the Annual General Meeting of Shareholders. The analysis technique used was multiple linear regression analysis. The research found that five variables of kind of ROA, CR, DER, EPS dan TATO simultaneously influence to dividend

  12. PENENTUAN DAERAH RAWAN GIZI BERDASARKAN ANALISIS SPATIAL

    Directory of Open Access Journals (Sweden)

    Noviati Fuada

    2012-11-01

    Full Text Available Latar Belakang : Riset Kesehatan Dasar telah dilakukan di Indonesia (RISKESDAS 2007. Riset telah mengumpulkan data-data yang terdiri dari data kesehatan yang menggambarkan status gizi anak di bawah lima (antrophometri data di seluruh wilayah Indonesia. Kenyataanya masih sedikit analisis dengan menggunakan metode GIS, oleh karena itu artikel ini akan dikaji dengan metode spasial. Kajian ini diharapkan dapat memberikan informasi faktual, yang dapat mendukung kebijakan daerah. Tujuan: Mengidentifikasi daerah kabupaten/provinsi rawan status gizi anak balita, Metode: Analisa GIS denganmenggunakan metode spasial (pengelompokan data dan overlay dengan cara union. Data RISKESDAS 2007. Hasil: Wilayah tingkat tinggi potensi rawan gizi bermasalah (bersumber overlay antara peta sebaran status gizi balita dengan peta sebaran KK miskin  adalah; Kota Tasikmalaya, Kab. Tasikmalaya, Cianjur, Garut, Ciamis, Bandung, Subang dan Majalengka. Wilayah tingkat tinggi berpotensi terkena infeksi penyakit (berdasarkan peta sebaran resiko Infeksi Penyakit dan pemanfaatan posyandu adalah: Kabupaten Purwakarta, Karawang, Bekasi, Bogor, Sukabumi, Tasikmalaya, Kota Tasikmalaya, Bekasi dan Bogor. Wilayah berpotensi rawan gizi kategori tinggi (bersumber pada 4 faktor/peta sebaran meliputi, Kabupaten Cianjur, Garut, Tasikmalaya dan Kota Tasikmalaya. Kasus Gizi bermasalah berdasarkan 3 indeks gabungan menyebar di seluruh wilayah Provinsi Jawa Barat. Wilayah kasus gizi bermasalah kategori tinggi, dan kategori sedang, sebagian besar  terjadi di wilayah Kabupaten. Baik kategori sedang maupun tinggi merupakan wilayah yang berdampingan. Gambaran ini mengarah pada fakta bahwa  masalah gizi cenderung merupakan masalah epidemiologi. Kesimpulan: Terdapat empat wilayah kabupaten status gizi yang paling serius dalam kategori tinggi meliputi, Kabupaten Cianjur, Garut, Tasikmalaya dan Kota Tasikmalaya.  Kata kunci: analisis spasial, status gizi, posyandu, rawan gizi 

  13. Diagnostics of low energy carbon fibre Z-pinch

    International Nuclear Information System (INIS)

    Time-resolved pinhole x-ray cameras, soft and hard x-ray detectors, electron and ion collectors, and optical schlieren method have been used at investigations of a carbon z pinch. The z pinch discharge was produced by exploding an ultrathin carbon fiber (6 m in diameter) located between the tips of conical electrodes of a small (0.5 kJ) z-pinch device. Several pulses of soft x-ray radiation with energy of 0.5-1.5 keV were observed near the current maximum. Also the observed ion and electron signals demonstrate appearance of 2 - 3 separate pulses with a mean energy differing by about two orders of magnitude. Short (10-20 ns) strongly asymmetric XUV radiation pulses, with the axial intensity more than 100 times higher than the radial intensity, were observed during 100-300 ns after the breakdown. (J.U.). 5 figs., 2 refs

  14. Experimental studies of an Extrap Z-Pinch

    International Nuclear Information System (INIS)

    Experimental studies of the formation, equilibrium and stability of a linear Extrap Z-pinch are reported on. The Z-pinch discharge is generated between electrodes along the Z-axis of a linear octupole field produced by currents in four Z-directed rods. The combined discharge current and rod currents produce a magnetic field having a separatrix with four null X-points which define the corners of a square shaped region where the high beta plasma discharge is contained. Bounding the pinch discharge with a separatrix produces equilibria which are stable against global kink modes for the 50-μsec duration of the discharge which corresponds to about 100 Alfven transit times. The equilibria, with line densities of about 3 x 1018m-1, are consistent in magnitude and scaling with the Bennet relation. (Author)

  15. Resolving microstructures in Z pinches with intensity interferometry

    International Nuclear Information System (INIS)

    Nearly 60 years ago, Hanbury Brown and Twiss [R. Hanbury Brown and R. Q. Twiss, Nature 178, 1046 (1956)] succeeded in measuring the 30 nrad angular diameter of Sirius using a new type of interferometry that exploited the interference of photons independently emitted from different regions of the stellar disk. Its basis was the measurement of intensity correlations as a function of detector spacing, with no beam splitting or preservation of phase information needed. Applied to Z pinches, X pinches, or laser-produced plasmas, this method could potentially provide spatial resolution under one micron. A quantitative analysis based on the work of Purcell [E. M. Purcell, Nature 178, 1449 (1956)] reveals that obtaining adequate statistics from x-ray interferometry of a Z-pinch microstructure would require using the highest-current generators available. However, using visible light interferometry would reduce the needed photon count and could enable its use on sub-MA machines

  16. Turbulent corona in a dense Z-pinch

    International Nuclear Information System (INIS)

    In this paper the author considers the convection which arises due to the MHD interchange instability of a superheated skin layer in a Z-pinch. The increase in size of the Z-pinch corona resulting from this process is a likely explanation for several unexpected results reported from experiments on Angara-5. This high-voltage high-current device has in recent experiments revealed intense evaporation of plasma from the surface of a Z-pinch, probably giving rise to recapture of the current of this low-density plasma. In these experiments an electric current of magnitude J ∼ 3 MA passed through a polyethylene rod of diameter OE 0 = 2 mm and height h ∼ 5 mm for a time ∼ 80 ns. After a time ∼ 50 ns the discharge gap was filled with plasma with a density ne ≥ 1019 cm-3 out to distances of 5-10 mm from the discharge axis. These experiments were partly aimed at verifying the basic hypotheses of the proposal for producing ignition of thermonuclear field in the constrictions of Z-pinches in already existing devices, with a resulting energy yield greater than breakeven. The phenomenon observed, according to Sasorov, can interfere with the high compression in the constrictions of a Z-pinch which is necessary to implement the ideas of Yan'kov. In the present work he discusses the mechanism for turbulent spreading of the superheated skin layer of a Z-pinch, which enables one to understand some of the unexpected results of these experiments

  17. Architecture of petawatt-class z-pinch accelerators

    International Nuclear Information System (INIS)

    We have developed an accelerator architecture that can serve as the basis of the design of petawatt-class z-pinch drivers. The architecture has been applied to the design of two z-pinch accelerators, each of which can be contained within a 104-m-diameter cylindrical tank. One accelerator is driven by slow (∼1 (micro)s) Marx generators, which are a mature technology but which necessitate significant pulse compression to achieve the short pulses (4 capacitors, store 98 MJ, and erect to 5 MV; (ii) 600 water-dielectric triplate intermediate-store transmission lines, which also serve as pulse-forming lines; (iii) 600 5-MV laser-triggered gas switches; (iv) three monolithic radial-transmission-line impedance transformers, with triplate geometries and exponential impedance profiles; (v) a 6-level 5.5-m-diameter 15-MV vacuum insulator stack; (vi) six magnetically insulated vacuum transmission lines (MITLs); and (vii) a triple-post-hole vacuum convolute that adds the output currents of the six MITLs, and delivers the combined current to a z-pinch load. The accelerator delivers an effective peak current of 52 MA to a 10-mm-length z pinch that implodes in 95 ns, and 57 MA to a pinch that implodes in 120 ns. The LTD-driven accelerator includes monolithic radial transformers and a MITL system similar to those described above, but does not include intermediate-store transmission lines, multimegavolt gas switches, or a laser trigger system. Instead, this accelerator is driven by 210 LTD modules that include a total of 1 x 106 capacitors and 5 x 105 200-kV electrically triggered gas switches. The LTD accelerator stores 182 MJ and produces a peak electrical power of 1000 TW. The accelerator delivers an effective peak current of 68 MA to a pinch that implodes in 95 ns, and 75 MA to a pinch that implodes in 120 ns. Conceptually straightforward upgrades to these designs would deliver even higher pinch currents and faster implosions

  18. A compact, coaxial shunt current diagnostic for X pinches

    Science.gov (United States)

    Wang, Liangping; Zhang, Jinhai; Li, Mo; Zhang, Xinjun; Zhao, Chen; Zhang, Shaoguo

    2015-08-01

    A compact coaxial shunt was applied in X-pinches experiments on Qiangguang pulsed power generator. The coaxial shunt was designed to have a compact construction for smaller inductance and more, for conveniently assembling upon the X pinch load structure. The coaxial shunt is also a cheap current probe and was easily built by research groups. The shunt can monitor a 100 kA high current with a 100 ns rise time. The calibration results showed that the probe used in the experiments has a resistance of 3.2 mΩ with an uncertainty of 3%, and its response time to the step signal is less than 7 ns.

  19. Self-pinching of pulsed laser beams during filamentary propagation

    International Nuclear Information System (INIS)

    Competing nonlinear optical effects that act on femtosecond laser pulses propagating in a self-generated light filament may give rise to a pronounced radial beam deformation, similar to the z-pinch contraction of pulsed high-current discharges. This self-generated spatial beam contraction is accompanied by a pulse break-up that can be beneficially exploited for on-axis temporal compression of the pulse. The pinching mechanism therefore explains the recently observed self-compression and the complicated spatio-temporal shapes typical for filament propagation experiments. (authors)

  20. Seeded perturbations in wire array Z-Pinches

    International Nuclear Information System (INIS)

    Controlled seeding of perturbations is employed to study the evolution of wire array z-pinch implosion instabilities which strongly impact x-ray production when the 3D plasma stagnates on axis. Wires modulated in radius exhibit locally enhanced magnetic field and imploding bubble formation at discontinuities in wire radius due to the perturbed current path. Wires coated with localized spectroscopic dopants are used to track turbulent material flow. Experiments and MHD modeling offer insight into the behavior of z-pinch instabilities.

  1. ELECTROSTATIC MODE ASSOCIATED WITH PINCH VELOCITY IN RFPS

    Energy Technology Data Exchange (ETDEWEB)

    DELZANNO, GIAN LUCA [Los Alamos National Laboratory; FINN, JOHN M. [Los Alamos National Laboratory; CHACON, LUIS [Los Alamos National Laboratory

    2007-02-08

    The existence of a new electrostatic instability is shown for RFP (reversed field pinch) equilibria. This mode arises due to the non-zero equilibrium radial flow (pinch flow). In RFP simulations with no-stress boundary conditions on the tangential velocity at the radial wall, this electrostatic mode is unstable and dominates the nonlinear dynamics, even in the presence of the MHD modes typically responsible for the reversal of the axial magnetic field at edge. Nonlinearly, this mode leads to two beams moving azimuthally towards each other, which eventually collide. The electrostatic mode can be controlled by using Dirichlet (no-slip) boundary conditions on the azimuthal velocity at the radial wall.

  2. Advisory expert system for energy analysis in industrial boilers; Sistema experto asesor en el analisis energetico de calderas industriales

    Energy Technology Data Exchange (ETDEWEB)

    Kemper Valverde, Nicolas; Lara Rosano, Felipe; Vazquez Nava, Rodolfo [Laboratorio de Inteligencia Artificial, Instituto de Ingenieria UNAM, Mexico, D. F. (Mexico)

    1994-12-31

    This paper presents an expert system for the operational analysis of industrial boilers, estimating the potential of heat recovery, in the small and medium size industry. The package is friendly, practical, flexible easy to maintain and expandable to take into consideration the user`s specific requirements and allows the analysis of the energy losses in the combustion, feed water, drains, and insulation, identifying the enhancements and estimating the saving potential, in energy as well as economical. [Espanol] En este trabajo se presenta un sistema experto para analizar la operacion de calderas industriales estimando el potencial de recuperacion de calor, en la pequena y mediana industria. El paquete es amigable, practico, flexible, facil en su mantenimiento y expandible para tomar en consideracion los requerimientos especificos de los usuarios y permite el analisis de las perdidas de energia en la combustion, agua de alimentacion, purgas y aislamientos, identificando las mejoras y estimando ahorros potenciales, tanto energeticos como economicos.

  3. ANALISIS GEN HAEMAGGLUTININ PADA VIRUS CAMPAK LIAR

    Directory of Open Access Journals (Sweden)

    Subangkit Subangkit

    2015-05-01

    Full Text Available AbstrakPenyakit Campak disebabkan oleh virus campak yang termasuk genus Morbilivirus dan Family Paramyxoviridae. Penyakit campak masih menjadi masalah kesehatan karena masih ditemukan Kejadian Luar Biasa (KLB di Indonesia. Salah satu penyebab terjadinya KLB tersebut diduga sebagaiakibat perbedaan antigenesitas antara strain vaksin yang digunakan dengan strain virus campak liar yang beredar di Indonesia. Penelitian ini bertujuan mendapatkan gambaran tentang karakteristik genetik gen Haemagglutinin virus campak liar yang ada di Indonesia. Spesimen yang digunakan sebanyak 27 isolat virus penyebab KLB dari 17 propinsi selama periode tahun 2003-2010. Isolat virus dilakukan pemeriksaan secara RT-PCR dan sekuensing dengan metode Sanger. Hasil sekuensing dianalisis dengan menggunakan perangkat lunak Bioedit 7.0 dan MEGA 4.0. Hasil penelitian didapatkan perbedaan 10 asam amino antara virus campak strain vaksin CAM-70 dan virus campak liar pada posisi D416N; K424T; V451M; N455T; V466I; I473T; F476L; Y481S atau Y481N; H495N; G505D. Kesimpulan penelitian ini adalah terdapat perbedaan karakteristik genetik antara virus campak liar di Indonesia berbeda dengan strain virus vaksin CAM-70.Kata kunci : Campak, Analisis Molekuler, Hemagglutinin, CD46AbstractMeasles is caused by virus belonging to the genus Morbilivirus and Family Paramyxoviridae. Measles is still a public health problem because outbreak of measles still found in Indonesia. Outbreak is suspected as a result of differences in antigenicity between vaccine strains used with wild-type measles virus strains circulating in Indonesia. This study aims to get genetic characteristics of wild-type measles virus haemagglutinin gene in Indonesia. The specimens were used 27 viral isolates from 17 provinces period 2003-2010. Viral isolates examined by RT-PCR and sequencing with Sanger method. Sequencing analysis were conducted using Bioedit 7.0 and MEGA 4.0 software. The results showed 10 amino acid differences

  4. Raices y tuberculos para el siglo 21: tendencias, projecciones y opciones de politica

    OpenAIRE

    Scott, Gregory J.; Rosegrant, Mark W.; Ringler, Claudia

    2000-01-01

    La gran importancia de las raices y tuberculos como fuente de ingresos para los agricultores pobres y como fuente de alimento para la poblacion de escasos recursos, tanto rural como urbana, es muchas veces ignorada en el debate sobre el mejoramiento de la seguridad alimentaria y la erradicacion de la pobreza en los paises en desarrollo. Es de esperarse que los analisis del presente informe, preparados en forma conjunta por el Centro Internacional de la Papa (CIP) y el Instituto Internacional ...

  5. Sheared flow stabilization experiments in the ZaP flow Z pinch

    International Nuclear Information System (INIS)

    The stabilizing effect of a sheared axial flow on the m=1 kink instability in Z pinches has been studied numerically with a linearized ideal magnetohydrodynamic model to reveal that a sheared axial flow stabilizes the kink mode when the shear exceeds a threshold. The sheared flow stabilizing effect is investigated with the ZaP (Z-Pinch) Flow Z-pinch experiment at the University of Washington. An axially flowing Z pinch is generated with a 1 m coaxial accelerator coupled to a pinch assembly chamber. The plasma assembles into a pinch 50 cm long with a radius of approximately 1 cm. An azimuthal array of surface mounted magnetic probes located at the midplane of the pinch measures the fluctuation levels of the azimuthal modes m=1, 2, and 3. After the pinch assembles a quiescent period is found where the mode activity is significantly reduced. Optical images from a fast framing camera and a ruby holographic interferometer indicate a stable, discrete pinch plasma during this time. Multichord Doppler shift measurements of impurity lines show a large, sheared flow during the quiescent period and low, uniform flow profiles during periods of high mode activity. Z-pinch plasmas have been produced that are globally stable for over 700 times the theoretically predicted growth time for the kink mode of a static Z pinch. The plasma has a sheared axial flow that exceeds the theoretical threshold for stability during the quiescent period and is lower than the threshold during periods of high mode activity

  6. Analisis Tingkat Kesejahteraan Masyarakat Pesisir Di Kecamatan Medan Labuhan

    OpenAIRE

    Ismail, Fakhri

    2013-01-01

    Tujuan penelitian ini adalah mengetahui tingkat kesejahteraan masyarakat pesisir di Kecamatan Medan Labuhan dengan menggunakan data primer untuk 100 responden yang mewakili seluruh populasi masyarakat pesisir di Kecamatan Medan Labuhan. Pengumpulan data dilakukan dengan menggunakan daftar kuesioner. Metode analisis yang digunakan adalah deskriptif kualitatif. Data yang terkumpul diolah dan disajikan dalam bentuk tabel Hasil penelitian menunjukkan bahwa masyarakat pesisir di Kecamatan Meda...

  7. Un’analisi strutturale: Il corvo bianco di P. Bigongiari

    Directory of Open Access Journals (Sweden)

    Luciano Vitacolonna

    2011-12-01

    Full Text Available Presentiamo qui un'analisi strutturale della lirica Il corvo bianco di Piero Bigongiari. Vengono così messi in luce sia gli strati del testo, sia le relazioni intra- e intertestuali. Attraverso lo scandaglio degli aspetti compositivi della poesia ne proponiamo infine una complessiva lettura simbolica.

  8. Analisis Perpindahan Merek Produk Minyak Goreng Dengan Menggunakan Rantai Markov

    OpenAIRE

    Tumanggor, Sabam D.

    2012-01-01

    Sabam Dameriama Tumanggor (070304029) dengan judul skripsi ”Analisis Perpindahan Merek Produk Minyak Goreng dengan Menggunakan Rantai Markov“. Penelitian ini dibimbing oleh Bapak Ir. Luhut Sihombing, MP dan Ir. Thomson Sebayang, MT. Penelitian ini bertujuan untuk menjelaskan pola perpindahan merek minyak goring dari satu merek ke merek lainnya yang dilakukan oleh ibu rumah tangga, untuk menganalisis apa saja yang menjadi pertimbangan ibu rumah ...

  9. Collapse of Z-pinch necks for inertial fusion

    International Nuclear Information System (INIS)

    The ignition is possible under the condition of collapring z-pinch neck up to the diameter 10-4cm. The current pulse with duration 10-7s and 107A must be applied to a cylinder of condensed D-T mixture in order to obtain the parameter ρr≥0.4 g/cm2. 22 refs

  10. Steady state theta pinch concept for slow formation of FRC

    International Nuclear Information System (INIS)

    A steady state high beta plasma flow through a channel along the magnetic field increasing downstream can be regarded as a ''steady state theta pinch'', because if we see the plasma riding on the flow we should observe very similar process taking place in a theta pinch. Anticipating to produce an FRC without using very high voltage technics such as the ones required in a conventional theta pinch, we have studied after the analogy a ''steady state reversed field theta pinch'' which is brought about by steady head-on collision of counter plasma streams along the channel as ejected from two identical co-axial plasma sources mounted at the both ends of the apparatus. The ideal Poisson and shock adiabatic flow models are employed for the analysis of the steady colliding process. It is demonstrated that an FRC involving large numbers of particles is produced only by the weak shock mode which is achieved in case energetic plasma flow is decelerated almost to be stagnated through Poisson adiabatic process before the streams are collided. (author)

  11. Diffusion-driven currents in a Z-pinch

    International Nuclear Information System (INIS)

    A model of a Z-pinch and related systems such as Extrap is considered where there is a hot fully ionized plasma core which is impermeable to neutral gas and being surrounded by a partially ionized cool boundary layer. The pinch is driven by an imposed toroidal (axial) electric field. The model should apply both to linear geometry at sufficiently long axial lengths and to toroidal geometry at large aspect ratios. The recirculation of matter in the boundary layer generates diffusion-driven 'bootstrap-like' currents, both in the toroidal and the poloidal (transverse) directions. The largest toroidal bootstrap currents arise at relatively low plasma densities, high temperatures of the core edge and weak toroidal magnetic fields. There is a low-density limit at which the core becomes 'permeable' to neutral gas and where the bootstrap currents and plasma-neutral gas interaction are distributed all over the plasma body. The toroidal bootstrap current reinforces the externally driven pinch current, and the poloidal bootstrap current produces a diamagnetic effect. The diffusion-driven current system is expected to become disturbed when the pinch radius approaches its upper limit, as defined by a magnetic separatrix or a metal limiter

  12. Laser emission from an embedded-pinch sheath

    International Nuclear Information System (INIS)

    Hot plasma pinches emit intense vacuum uv radiation. In the embedded configuration cold surrounding gas damps pinch instabilities and insulates the plasma from vessel walls. When such a pinch is formed within a high-Z gas its copious uv production may induce photolytic processes in the surrounding gas blanket. To explore this process we have investigated laser-initiated high-Z gas-embedded pinches both theoretically and experimentally. Focusing on high-Z and high density media leads to a simplification in the problem because the plasma becomes optically dense and energy is lost principally through black-body radiation. Radiated power densities of 107-108W/cm2 have been measured. This flux drives sequential luminous photolytic waves into the enveloping gas at radial velocities in excess of 107 cm/sec. XeF (B-X) laser radiation was generated within the photolytic sheath by installing a 350 nm optical resonator and seeding the gas with XeF2

  13. Investigation of plasma turbulence in a theta-pinch-discharge

    International Nuclear Information System (INIS)

    This thesis is concerned with investigations of plasma turbulence in a 3 KJ Theta-Pinch during implosion by high-frequency Stark-effect and Thomson scattering. The next points are modifications of electron-distribution function by ionization in low preionizized turbulent plasma and energy losses by particle flow and heat flow at the ends. (HT)

  14. Kinetic theory of sausage instability of z-pinch

    International Nuclear Information System (INIS)

    The linear problem of the development of the sausage instability of a z-pinch is analyzed. Kinetic effects are taken into account for the case of a current with an ideal skin effect. The electrons of the plasma are assumed to be cold, and the ions collisionless. It is also assumed that the magnetic field in the pinch does not affect the motion of the ions. The ions are reflected specularly from the potential jump which arises at the plasma boundary. In the case of long-wave perturbations, with ka much-lt 1 (a is the pinch radius, and k is the wave number), the instability growth rate differs from the hydrodynamic growth rate only by a numerial factor. For short-wave perturbations, ka much-gt 1, kinetic effects lead to a substantial decrease in the growth rate [by a factor of (ka)1/2] from that in the hydrodynamic description. It thus becomes possible to explain the improved stability of z-pinches which is observed experimentally

  15. A Pinching Strategy for Fabrics Using Wiping Deformation

    Directory of Open Access Journals (Sweden)

    Mizuho Shibata

    2016-04-01

    Full Text Available This paper discusses a strategy by which a robotic hand can use the physical properties of a fabric to pinch the fabric. Pinching may be accomplished by using a wiping motion, during which the movement and deformation of a deformable object occur simultaneously. The wiping motion differs from the displacement of a deformable object. During the wiping motion, there is contact, but no relative movement, between the manipulator and the object, whereas, during displacement, there is both contact and relative movement between the object and the floor. This paper first describes wiping motion and distinguishes wiping slide from wiping deformation by displacement of the internal points of an object. Wiping motion is also shown to be an extended scheme of pushing and sliding of rigid objects. Our strategy for pinching a fabric is accomplished with a combination of wiping deformation and residual deformation of the fabric under unloaded conditions. Using this strategy, a single-armed robotic hand can pinch both surfaces of the fabric without handover motion.

  16. Parametric dependences of momentum pinch and Prandtl number in JET

    NARCIS (Netherlands)

    Tala, T.; Salmi, A.; Angioni, C.; Casson, F. J.; Corrigan, G.; Ferreira, J.; Giroud, C.; Mantica, P.; Naulin, V.; Peeters, A.G.; Solomon, W. M.; Strintzi, D.; Tsalas, M.; Versloot, T. W.; de Vries, P. C.; Zastrow, K. D.

    2011-01-01

    Several parametric scans have been performed to study momentum transport on JET. A neutral beam injection modulation technique has been applied to separate the diffusive and convective momentum transport terms. The magnitude of the inward momentum pinch depends strongly on the inverse density gradie

  17. Comment on Turbulent Equipartition Theory of Toroidal Momentum Pinch

    International Nuclear Information System (INIS)

    This response demonstrates that the comment by Peeters et al. contains an incorrect and misleading interpretation of our paper (Hahm et al., Phys. Plasmas 15, 055902 (2008)) regarding the density gradient dependence of momentum pinch and the turbulent equipartition (TEP) theory

  18. Parametric dependences of momentum pinch and Prandtl number in JET

    DEFF Research Database (Denmark)

    Tala, T.; Salmi, A.; Angioni, C.;

    2011-01-01

    Several parametric scans have been performed to study momentum transport on JET. A neutral beam injection modulation technique has been applied to separate the diffusive and convective momentum transport terms. The magnitude of the inward momentum pinch depends strongly on the inverse density gra...

  19. Classical transport in a non-circular z-pinch

    International Nuclear Information System (INIS)

    A method is devised, in which particle and heat fluxes are found by solving the heat balance equation self-consistently for specified profiles. The procedure is applied to an equilibrium which corresponds to a non-circular z-pinch. (author)

  20. ANALISIS MODEL KEPUASAN TERHADAP PEMBELIAN ULANG

    Directory of Open Access Journals (Sweden)

    Naili Farida

    2014-09-01

    Full Text Available Tujuan penelitian ini yaitu untuk menguji pengaruh brand equity, nilai pelanggan dan lifestyle yang dimediasi kepuasan konsumen terhadap pembelian ulang produk gadget di Kota Semarang. Responden dalam penelitian ini adalah seluruh konsumen yang telah melakukan pembelian produk gadget merek Samsung, sebanyak 120 orang. Teknik sampling yang digunakan yaitu purposive sampling. Teknik analisis yang digunakan yaitu Partial Least Square (PLS. Hasil penelitian menunjukkan bahwa terdapat pengaruh brand equity terhadap kepuasan, namun dalam konteks lifestyle dan nilai pelanggan tidak ada pengaruh terhadap kepuasan. Sedangkan kepuasan menunjukkan adanya pengaruh terhadap pembelian ulang. Diharapkan dari hasil penelitian ini mampu meningkatkan pembelian ulang melalui brand equity, lifestyle dan nilai pelanggan dalam konteks kepuasan. The objective of the research was to test the influence of brand equity, customer value and lifestyle which were mediated by consumer satisfaction toward re-purchasing of gadget products in Semarang. The respondents of the study were all consumers who have purchased Samsung gadget products. It was a purposive sampling study with 120 respondents. The data were analyzed by Partial Least Square (PLS. The result of the study showed that there was an influence of brand equity toward satisfaction, but in the lifestyle context and customer value did not give any influence toward satisfaction. Whereas; the satisfaction gave influence toward re-purchase. It is expected that this study can increase the repurchasethrough brand equity, lifestyle and customer values in the satisfaction context.

  1. Analisis SWOT untuk Penentuan Strategi Optimalisasi Infrastruktur

    Directory of Open Access Journals (Sweden)

    Sri Wahyuningsih

    2012-12-01

    Full Text Available Undang-undang No.38 tahun 2009 tentang Pos memberikan keleluasaan penyelenggara pos untuk melakukan pengembangan produksi serta peningkatan infrastruktur, yang mendukung daya saing masing-masing penyelenggara pos. Sebagai badan usaha milik negara, PT.Pos Indonesia memiliki jaringan terintegrasi sampai ke pedesaan dan daerah transmigrasi, yang diketahui hampir 100% jaringan dibangun oleh pemerintah. Jaringan Pos adalah jaringan fisik maupun virtual untuk mendukung terselenggaranya layanan pos. Jumlah titik layanan mencapai 24 ribu titik layanan yang menjangkau hampir 100% kecamatan dan 42 % kelurahan/desa. Untuk mengetahui strategi dalam rangka optimalisasi infrastruktur di PT.Pos Indonesia, dilakukan penelitian dengan pendekatan kualitatif dan analisis SWOT dan hasilnya penggambaran pada Matrik Grand Strategi, posisi pada  Kuadran I (positif, positif, artinya, PT.Pos Indonesia khususnya untuk KPRK Jakarta Pusat10000, KPRK Jakarta Utara14000 dan KPRK Bandung 40000 manajemen organisasinya sudah solid, dan banyak mempunyai peluang. Ekspansi dapat dilanjutkan untuk memperbesar pertumbuhan dan pengembangan produk, namun aspek SDM masih perlu ditingkatkan.

  2. ANALISIS PERBANDINGAN SPAP, IAS DAN SPKN

    Directory of Open Access Journals (Sweden)

    Maylia Pramono Sari

    2012-03-01

    Full Text Available Dalam mewujudkan Good Goveronance  akan dilakukan analisis perbandingan mengenai standar pemeriksaan nasional yaitu SPAP, ISA, dan SPKN untuk menemukan standar yang lebih tepat dan lebih lengkap untuk pemeriksaan sektor publik. Persamaan SPKN dan ISS  adalah tanggungjawab manajemen dan tanggungjawab auditor sedangkan perbedaannya adalah badan yang menerbitkannya. Perbedaan yang mendasar terletak pada karakter pemeriksaan BPK. Karakter tersebut adalah keharusan pemeriksa BPK untuk merancang prosedur pemeriksaan terhadap kepatuhan yang terkait dengan pemeriksaan yang dilakukan dan waspada atas penyimpangan lainnya. Abstract To realize Good Governance, it needs a comparative analysis for finding out the national standardization of SPAP, ISA, and SPKN . It is used for auditing public sector. SPKN and ISA have similarities and difference. Both SPKN and ISA have the same responsibility of management and audit. SPKN and ISA  have different characteristics in auditing. The compliance of audit procedure is obligatory for  BPK. Moreover, it becomes the strength of BPK RI and the one that make BPK and KAP different.Keywords: SPAP; ISA; SPKN

  3. Hubungan Sudut Interinsial dengan Jaringan Lunak Wajah Berdasarkan Analisis Steiner pada Mahasiswa FKG USU Ras Deutro Melayu

    OpenAIRE

    Akbar, Fajri

    2015-01-01

    Kelainan gigi dan jaringan lunak wajah atau dentofasial merupakan masalah penyakit gigi yang sering terjadi. Analisis sefalometri sering digunakan oleh dokter gigi untuk mengetahui pertumbuhan skeletal, diagnosis sefalometri, perencanaan perawatan, hasil perawatan dan stabilitas hasil perawatan. Analisis Steiner merupakan salah satu analisis yang sering dipakai dalam ilmu kedokteran gigi. Kelompok etnik yang berbeda cenderung memiliki bentuk tengkorak dan rahang yang berbeda. Tujuan Penelitia...

  4. Dense Z-pinch research - Experiment and theory

    International Nuclear Information System (INIS)

    Dense Z-pinch research at Imperial College is currently dominated by the design and construction of the MAGPIE generator which can deliver up to 2 MA at 2.4 MV for 200 ns into a Z-pinch load. It will be operational in 1993 and allow an investigation into radiative collapse at currents above the Pease-Braginskii current, as well as the attainment of Z-Pinch under thermonuclear conditions. In a joint experiment at the Ecole polytechnique, enhanced stability has recently been found by collapsing a current carrying plasma jet on to a fibre. In theoretical work a general class of non-stationary Z-pinch equilibria has been studied, distinguishing between cases of rising and falling current. A stability analysis of the m = 0 mode using the Chew, Goldberger and Low (CGL) model (valid in the small Larmor radius limit) with an anisotropic equilibrium shows that somewhat enhanced stability can be achieved if P perpendicular0 > Pparallel0. However, CGL absolute stability to the m = 0 mode can only be achieved in the gas embedded pinch. For stability with finite or large ion Larmor radius effects, two methods based on the Vlasov fluid mode are being studied; the first is a linear initial value code, FIGARO, and the second uses a variational formulation of the eigenvalue equation. For a parabolic pressure profile the growth rate falls sharply to a minimum value as the ion Larmor radius is increased. Non-linear MHD evolution of m = 1 kink is studied with a simplified model. Finally, Ettinghausen and Nernst effects are shown to remove a surface thermal instability and cause a slight central peaking of the temperature. (author). 25 refs, 7 figs

  5. Analysis of turbomachineries by means of the application of the SMDTurbo system; Analisis de turbomaquinas mediante la aplicacion del sistema SMDTurbo

    Energy Technology Data Exchange (ETDEWEB)

    Zuniga, Helen; Garcia, Ernesto; Bernabe, Jose; Aboites, Fernando [CIATEQ, A.C., Queretaro (Mexico)

    2007-11-15

    In this paper is presented an integral system in experimental phase developed by CIATEQ for the monitoring and acquisition of involved physical variables in the turbo-machinery analysis. The system has been denominated SMDTurbo (System of Monitoring and Diagnosis for Turbo machinery) and its purpose is to realize a diagnosis (on the basis of mathematical and graphical tools) of the performance of the turbo machinery through the measurement of variables such as pressure, temperature and vibration. The obtained data from these elements is used for its later processing of analysis and diagnosis by means of specialized software with which the performance of the turbo machinery will be able to be performed (TM). Preliminary results of the proposal are presented. [Spanish] En este trabajo se presenta un sistema integral en fase experimental desarrollado por CIATEQ para el monitoreo y adquisicion de variables fisicas involucradas en el analisis de turbomaquinaria. El sistema se ha denominado SMDTuro (Sistema de Monitoreo y Diagnostico para Turbomaquinaria) y tiene como proposito realizar un diagnostico (en base a herramientas matematicas y graficas) del rendimiento de la turbomaquina a traves de la medicion de variables como presion, tempreratura y vibracion. La informacion obtenida de estos elementos se utiliza para su posterior proceso de analisis y diagnostico mediante un software especializado con el cual se podra realizar el rendimiento de la turbomaquinaria (TM). Se presentan resultados preliminares de la propuesta.

  6. ANALISIS KINERJA DENGAN MENGGUNAKAN PENDEKATAN RASIO CAMEL

    Directory of Open Access Journals (Sweden)

    Sri Murdiati

    2015-06-01

    Full Text Available Tujuan penelitian ini adalah untuk menganalisis tingkat kesehatan bank dilihat dari kategori CAMEL. Metode penelitian yang digunakan adalah studi kasus di PD BPR BKK Banjarharjo.Dalam menguji hipotesis digunakan alat analisis CAMEL. Hasil penelitian ini yaitu modal pada 2008 sampai 2010 termasuk dalam kriteria sehat. ROA meningkat 2008 sampai 2010 dengan kriteria sehat bagi biaya operasional yang dikeluarkan oleh pendapatan operasional yang seimbang. Rasio Kas tahun 2008 sampai 2010 termasuk dalam kriteria sehat berarti bank memiliki kemampuan untuk mengelola asset yang digunakan untuk membayar kewajiban. LDR mengalami tren yang signifikan selama tahun 2008 sampai 2010 sehingga dana yang diterima bank untuk meningkatkan baik tabungan, deposito berjangka, modal inti, yang berarti kemampuan bank untuk meningkatkan penyaluran kredit, IRR menunjukan nilai positif dalam menghadapi resiko pasar.Pengembangan tingkat kesehatan pada tahun 2008 sampai 2010 untuk komponen Capital, Assets, Laba dan Likuiditas meningkat. The goal of this research is to analyze the healtiness of banks seen from CAMEL category. The research applied a case study in PD BPR BKK Banjarharjo. The hypotheses tested using CAMEL analysis tools. The result of the study is that the modal used 2008 until 2010 is consideredin a healthy criteria. The increasing ROA in 2008 until 2010 is considered healthy criteria for operational expenses incurred by the operating income. Such condition meant that the banks are able to manage the assets which are used to pay the obligations. The significant increasing of LDR over the years 2008 until 2010 makes the received funds by the bank to increase the savings deposits, time deposits and the core capital. As the recunts, the banks are able to increase credit disstribution. More over, the IRR showed a positive values in the face of market risks and the development of healthy levels in 2008 until 2010 for the components of Capital, Assets, Earnings and

  7. ANALISIS FAKTOR DAYA SAING DI KABUPATEN SEMARANG

    Directory of Open Access Journals (Sweden)

    Eka Handriani

    2010-03-01

    Full Text Available Jika perusahaan dapat mengoptimalkan penggunaan sumberdaya maka perusahaan mampu menghasilkan sustained competitive advantage. Tujuan dari penelitian ini adalah untuk membuktikan bahwa faktor internal dan eksternal, keterampilan pengusaha dan strategi yang diterapkan dalam UKM Kabupaten Semarang berpengaruh terhadap keunggulan kompetitif baik secara simultan dan parsial. Pengusaha mikro memiliki potensi besar dalam ekonomi nasional dan lokal sesuai dengan periode pasar bebas. Namun, etos dan persaingan masih dalam tingkat rendah. Penyebab utama dari masalah ini berasal dari faktor tenaga lingkungan, di antaranya adalah faktor internal dan eksternal keterampilan pengusaha, strategi, dan etos. Sebuah strategi yang akurat diperlukan untuk memecahkan masalah ini. Penelitian ini dilakukan pada 60 pengusaha mikro melalui empat variabel dependen dan satu variabel independen dengan menggunakan alat analisis statistik program SPSS. Hasilnya menunjukkan bahwa faktor internal dan eksternal, keterampilan pengusaha, strategi dan etos telah signifikan berpengaruh pada keunggulan kompetitif yang diterapkan oleh pengusaha mikro di Kabupaten Semarang secara parsial maupun simultan. The purpose of this research is to attest that internal and external factor, entrepreneur skill and strategy which applied in the UKM of Kabupaten Semarang are influence to the competitive advantage simultaneously and partially. Micro entrepreneur has great potency in the national and local economic according to this free market period. However, it is ethos and competition still in the low level. The main cause of this problem come up from environmental exertion factor, among them are internal and external factor the entrepreneur skill, strategy, and ethos. An accurate strategy is needed to solve this problem. This research has been done on 60 micro entrepreneurs through four dependent variables and one independent variable using to SPSS statistic program. The result shown that

  8. An Inertial-Fusion Z-Pinch Power Plant Concept

    International Nuclear Information System (INIS)

    With the promising new results of fast z-pinch technology developed at Sandia National Laboratories, we are investigating using z-pinch driven high-yield Inertial Confinement Fusion (ICF) as a fusion power plant energy source. These investigations have led to a novel fusion system concept based on an attempt to separate many of the difficult fusion engineering issues and a strict reliance on existing technology, or a reasonable extrapolation of existing technology, wherever possible. In this paper, we describe the main components of such a system with a focus on the fusion chamber dynamics. The concept works with all of the electrically-coupled ICF proposed fusion designs. It is proposed that a z-pinch driven ICF power system can be feasibly operated at high yields (1 to 30 GJ) with a relatively low pulse rate (0.01-0.1 Hz). To deliver the required current from the rep-rated pulse power driver to the z-pinch diode, a Recyclable Transmission Line (RTL) and the integrated target hardware are fabricated, vacuum pumped, and aligned prior to loading for each power pulse. In this z-pinch driven system, no laser or ion beams propagate in the chamber such that the portion of the chamber outside the RTL does not need to be under vacuum. Additionally, by utilizing a graded-density solid lithium or fluorine/lithium/beryllium eutectic (FLiBe) blanket between the source and the first-wall the system can breed its own fuel absorb a large majority of the fusion energy released from each capsule and shield the first-wall from a damaging neutron flux. This neutron shielding significantly reduces the neutron energy fluence at the first-wall such that radiation damage should be minimal and will not limit the first-wall lifetime. Assuming a 4 m radius, 8 m tall cylindrical chamber design with an 80 cm thick spherical FLiBe blanket, our calculations suggest that a 20 cm thick 6061-T6 Al chamber wall will reach the equivalent uranium ore radioactivity level within 100 years after a 30

  9. An Inertial-Fusion Z-Pinch Power Plant Concept

    Energy Technology Data Exchange (ETDEWEB)

    DERZON,MARK S.; ROCHAU,GARY E.; DEGROOT,J.; OLSON,CRAIG L.; PETERSON,P.; PETERSON,R.R.; SLUTZ,STEPHEN A.; ZAMORA,ANTONIO J.

    2000-12-15

    With the promising new results of fast z-pinch technology developed at Sandia National Laboratories, we are investigating using z-pinch driven high-yield Inertial Confinement Fusion (ICF) as a fusion power plant energy source. These investigations have led to a novel fusion system concept based on an attempt to separate many of the difficult fusion engineering issues and a strict reliance on existing technology, or a reasonable extrapolation of existing technology, wherever possible. In this paper, we describe the main components of such a system with a focus on the fusion chamber dynamics. The concept works with all of the electrically-coupled ICF proposed fusion designs. It is proposed that a z-pinch driven ICF power system can be feasibly operated at high yields (1 to 30 GJ) with a relatively low pulse rate (0.01-0.1 Hz). To deliver the required current from the rep-rated pulse power driver to the z-pinch diode, a Recyclable Transmission Line (RTL) and the integrated target hardware are fabricated, vacuum pumped, and aligned prior to loading for each power pulse. In this z-pinch driven system, no laser or ion beams propagate in the chamber such that the portion of the chamber outside the RTL does not need to be under vacuum. Additionally, by utilizing a graded-density solid lithium or fluorine/lithium/beryllium eutectic (FLiBe) blanket between the source and the first-wall the system can breed its own fuel absorb a large majority of the fusion energy released from each capsule and shield the first-wall from a damaging neutron flux. This neutron shielding significantly reduces the neutron energy fluence at the first-wall such that radiation damage should be minimal and will not limit the first-wall lifetime. Assuming a 4 m radius, 8 m tall cylindrical chamber design with an 80 cm thick spherical FLiBe blanket, our calculations suggest that a 20 cm thick 6061-T6 Al chamber wall will reach the equivalent uranium ore radioactivity level within 100 years after a 30

  10. ANALISIS TINGKAT KAPABILITAS SISTEM INFORMASI RUMAH SAKIT BERDASARKAN COBIT 5 (MEA01) PADA RSUD TUGUREJO SEMARANG

    OpenAIRE

    Ariel Bagus Nugroho; Amiq Fahmi

    2015-01-01

    RSUD Tugurejo Semarang merupakan Rumah Sakit kelas B milik pemerintah Provinsi Jawa Tengah yang menyediakan pelayanan jasa untuk masyarakat. Dalam manajemen pengolahan data, RSUD Tugurejo Semarang telah menggunakan sistem informasi rumah sakit. Untuk mengetahui apakah sistem informasi telah berjalan seperti yang diharapkan, maka perlu dilakukan analisis tatakelola teknologi informasi. Pada penelitian ini analisis tatakelola teknologi informasi berfokus pada proses pengawasan, evaluasi dan pen...

  11. Analisis Makna Peribahasa dalam Bahasa Melayu Riau Kabupaten Kepulauan Meranti: Kajian Semantik

    OpenAIRE

    Lumban Gaol, Angelia Ramita

    2015-01-01

    Penelitian ini berjudul Analisis Makna Peribahasa dalam Bahasa Melayu Riau Kabupaten Kepulauan Meranti: Kajian Semantik. Desa Selatpanjang di Kecamatan Tebing Tinggi Kabupaten Kepulauan Meranti merupakan salah satu desa yang penulis teliti. Penelitian ini bertujuan untuk: 1) Menjelaskan jenis-jenis peribahasa dalam bahasa Melayu Riau Kabupaten Kepulauan Meranti; 2) Mendeskripsikan makna peribahasa dalam bahasa Melayu Riau Kabupaten Kepulauan Meranti. Penelitian tentang Analisis Makna Peribaha...

  12. Transport and Measurements of High-Current Electron Beams from X pinches

    Science.gov (United States)

    Agafonov, Alexey V.; Mingaleev, Albert R.; Romanova, Vera M.; Tarakanov, Vladimir P.; Shelkovenko, Tatiana A.; Pikuz, Sergey A.; Blesener, Isaac C.; Kusse, Bruce R.; Hammer, David A.

    2009-01-01

    Generation of electron beams is an unavoidable property of X-pinches and other pulsed-power-driven pinches of different geometry. Some issues concerning high-current electron beam transport from the X pinch to the diagnostic system and measurements of the beam current by Faraday cups with different geometry's are discussed. Of particular interest is the partially neutralized nature of the beam propagating from the X-pinch to a diagnostic system. Two scenarios of electron beam propagation from X-pinch to Faraday cup are analyzed by means of computer simulation using the PIC-code KARAT. The first is longitudinal neutralization by ions extracted from plasma at an output window of the X-pinch diode; the second is the beam transport through a plasma background between the diode and a diagnostic system.

  13. Transport and Measurements of High-Current Electron Beams from X pinches

    International Nuclear Information System (INIS)

    Generation of electron beams is an unavoidable property of X-pinches and other pulsed-power-driven pinches of different geometry. Some issues concerning high-current electron beam transport from the X pinch to the diagnostic system and measurements of the beam current by Faraday cups with different geometry's are discussed. Of particular interest is the partially neutralized nature of the beam propagating from the X-pinch to a diagnostic system. Two scenarios of electron beam propagation from X-pinch to Faraday cup are analyzed by means of computer simulation using the PIC-code KARAT. The first is longitudinal neutralization by ions extracted from plasma at an output window of the X-pinch diode; the second is the beam transport through a plasma background between the diode and a diagnostic system.

  14. Developments of sausages in a z-pinch with short-wave perturbation of a boundary

    International Nuclear Information System (INIS)

    A numeric simulation of sausage evolution in z-pinch during short-wave excitation of the boundary of plasma column pinch is carried out. The simulation has shown that due to nonlinear development of sausages in a pinch plasma colomn the cavities filled with a magnetic field in a rarefied pinch plasma are formed. Simultaneously compact column of tense plasma whose temperature is much higher than the average temperature of pinch plasma column are formed on the pinch axis. In the region of inlet in the cavity plasma is radially directed due to ponderomotoric force 1/2 x jB up to velocities greatly increasing the thermal velocity of ions in a plasma column

  15. Numerical-experimental analysis of a rin AISI{sub 7}Mg Alloy; Analisis numerico experimental de un rin de aleacion AISi{sub 7}Mg

    Energy Technology Data Exchange (ETDEWEB)

    Sauceda Mesa, Israel; Mata Lucero, Omar; Tirado Delgado, Luis; Ocampo Diaz, Juan de Dios [Universidad Autonoma de Baja California, Mexicali, Baja California (Mexico)

    2005-10-15

    The present work shows the results obtained from an investigation mode on the behaviour of a rin of alloy AISi{sub 7}Mg, which is used in compact Volkswagen's cars. Due to two kind of analysis were realized, firstly an experimental and numerical analysis was done, using a special machine for test the flexionante torque and material fatigue, besides was used an equipment of laser to scanner zone with strength concentrations and the maximum displacement amplitudes. The second analysis was done with the finite element technique, using the software ANSYS and CATIA. The difference between life fatigue cycles obtained from the two analyses was 0.6%. While the time optimize by MEF, was of 85% less than experimental analysis. [Spanish] En el presente trabajo se hicieron investigaciones del comportamiento de un rin de aleacion AISi{sub 7}Mg, el cual es usado en automoviles compactos de volkswagen (VW). Para esto, se realizo analisis experimental y numerico. En el primero se utilizo una maquina para prueba de fatiga de momento flexionante, un equipo de medicion de laser escaner donde se detectaron las zonas de concentraciones de esfuerzos y la maxima amplitud de desplazamiento en el rin. Mientras que en el segundo se obtuvieron los esfuerzos que ocasionaban la fatiga por el elemento finito, utilizando los paquetes de computo Ansys y Catia. La diferencia de los ciclos de vida de fatiga obtenidos entre ambos analisis fue del 0.6%. Mientras que el tiempo que se optimizo por el MEF, fue de un 85% menos que el analisis experimental.

  16. X pinch a point x-ray source

    International Nuclear Information System (INIS)

    X ray emission from an X pinch, a point x-ray source has been studied using a pin-hole camera by a 30 kV, 7.2 μ F capacitor bank. The wires of different material like W, Mo, Cu, S.S.(stainless steel) and Ti were used. Molybdenum pinch gives the most intense x-rays and stainless steel gives the minimum intensity x-rays for same bank energy (∼ 3.2 kJ). Point x-ray source of size (≤ 0.5 mm) was observed using pin hole camera. The size of the source is limited by the size of the pin hole camera. The peak current in the load is approximately 150 kA. The point x-ray source could be useful in many fields like micro lithography, medicine and to study the basic physics of high Z plasmas. (author). 4 refs., 3 figs

  17. Magnetic Pinching of Hyperbolic Flux Tubes I. Basic Estimations

    CERN Document Server

    Titov, V S; Neukirch, T

    2003-01-01

    The concept of hyperbolic flux tubes (HFTs) is a generalization of the concept of separator field lines for coronal magnetic fields with a trivial magnetic topology. An effective mechanism of a current layer formation in HFTs is proposed. This mechanism is called magnetic pinching and it is caused by large-scale shearing motions applied to the photospheric feet of HFTs in a way as if trying to twist the HFT. It is shown that in the middle of an HFT such motions produce a hyperbolic flow that causes an exponentially fast growth of the current density in a thin force-free current layer. The magnetic energy associated with the current layer that is built up over a few hours is sufficient for a large flare. Other implications of HFT pinching for solar flares are discussed as well.

  18. Bubble Pinch-Off in a Rotating Flow

    DEFF Research Database (Denmark)

    Bergmann, Raymond; Andersen, Anders Peter; van der Meer, Devaraj;

    2009-01-01

    bubbles which are carried down by the flow. Using high-speed imaging we find that the minimal neck radius of the unstable tip decreases in time as a power law with an exponent close to 1/3. This exponent was found by Gordillo et al. [Phys. Rev. Lett. 95, 194501 (2005)] to govern gas flow driven pinch......We create air bubbles at the tip of a "bathtub vortex" which reaches to a finite depth. The bathtub vortex is formed by letting water drain through a small hole at the bottom of a rotating cylindrical container. The tip of the needlelike surface dip is unstable at high rotation rates and releases......-off, and indeed we find that the volume oscillations of the tip creates a considerable air flow through the neck. We argue that the Bernoulli pressure reduction caused by this air flow can become sufficient to overcome the centrifugal forces and cause the final pinch-off....

  19. Modeling Z-Pinch implosions in two dimensions

    International Nuclear Information System (INIS)

    Ideally, simulations of Z-Pinch implosions should provide useful information about important physics processes underlying observed experimental results and provide design capabilities for future experiments. With this goal the authors have developed a methodology for simulating hollow Z-Pinches in two dimensions and applied it to experiments conducted on the Pegasus I and Pegasus II capacitor banks, the Procyon explosion generator system, and the Saturn and PBFA-Z accelerators. In comparisons with experimental results the simulations have reproduced important features of the current drive, spectrum, radiation pulse shape, peak power and total radiated energy. Comparison of the instability development in the simulations with visible light framing camera photos has shown a close correlation with the observed instability wavelengths and amplitudes. Using this methodology the authors are analyzing recent Saturn and PBFA-Z experiments and applying the 2-D modeling in developing applications such as the dynamic hohlraum

  20. Modeling the Parker instability in a rotating plasma screw pinch

    CERN Document Server

    Khalzov, I V; Katz, N; Forest, C B; 10.1063/1.3684240

    2012-01-01

    We analytically and numerically study the analogue of the Parker (magnetic buoyancy) instability in a uniformly rotating plasma screw pinch confined in a cylinder. Uniform plasma rotation is imposed to create a centrifugal acceleration, which mimics the gravity required for the classical Parker instability. The goal of this study is to determine how the Parker instability could be unambiguously identified in a weakly magnetized, rapidly rotating screw pinch, in which the rotation provides an effective gravity and a radially varying azimuthal field is controlled to give conditions for which the plasma is magnetically buoyant to inward motion. We show that an axial magnetic field is also required to circumvent conventional current driven magnetohydrodynamic (MHD) instabilities such as the sausage and kink modes that would obscure the Parker instability. These conditions can be realized in the Madison Plasma Couette Experiment (MPCX). Simulations are performed using the extended MHD code NIMROD for an isothermal...

  1. D-D fusion experiments using fast Z pinches

    International Nuclear Information System (INIS)

    The development of high current (I > 10 MA) drivers provides the authors with a new tool for the study of neutron-producing plasmas in the thermal regime. The imploded deuterium mass (or collisionality) increases as I2 and the ability of the driver to heat the plasma to relevant fusion temperatures improves as the power of the driver increases. Additionally, fast (2 fiber arrays were imploded in a fast z-pinch configuration on Sandia's Saturn facility generating up to 3 x 1012 D-D neutrons. These experiments were designed to explore the physics of neutron-generating plasmas in a z-pinch geometry. Specifically, the authors intended to produce neutrons from a nearly thermal plasma where the electrons and ions have a nearly Maxwellian distribution. This is to be clearly differentiated from the more usual D-D beam-target neutrons generated in many dense plasma focus (DPF) devices

  2. A 600 MW(e) reversed field pinch reactor study

    International Nuclear Information System (INIS)

    The Reversed Field Pinch is an axisymmetric toroidal magnetic system in which the stable confinement of high β plasma has already been demonstrated experimentally. This study has reviewed the plasma physics relevant to a reactor based on the Reversed Field Pinch, defined a possible set of reactor parameters and undertaken a preliminary consideration of the mechanical and electrical engineering problems of this system. The design assumes pulsed operation without refuelling during the burn, ignition by ohmic heating alone, and the use of normal (i.e. not superconducting) magnetic field windings. For the chosen net output of 600 MW(e) and mean neutron wall loading of 1.5MW/m2 the plasma minor and major radii are 1.75m and 16m respectively. The energy multiplication factor Q of the system is 5.9. (author)

  3. Spectroscopic diagnosis of foam z-pinch plasmas on SATURN

    International Nuclear Information System (INIS)

    Solid and annular silicon aerogel and agar foams were shot on the accelerator SATURN to study plasma initiation, acceleration, and stagnation. SATURN delivers 7 MA with a 50 nsec rise time to these foam loads. We fielded several spectroscopic diagnostics to measure plasma parameters throughout the z-pinch discharge. A spatially resolved single frame time-gated EUV spectrometer measured the extent of plasma ablation off the surface foam. A time integrated crystal spectrometer showed that characteristic K shell radiation of silicon in the aerogel and of S and Na impurities in the agar were all attenuated when the foam loads were coated with a conductive layer of gold. The time resolved pinhole camera showed that in general the quality of the pinch implosions was poor but improved with increasing efforts to improve current continuity such as prepulse and conductive coatings

  4. Dense X-pinch plasmas for x-ray microlithography

    International Nuclear Information System (INIS)

    The authors report experimental results from a study of the radiation emission from aluminum and magnesium x-pinch experiments. The single cross x-pinch, driven by the 0.5 TW, 40ns pulse width Lion accelerator, consists of 2-8 fine wires stretched between the output electrodes of Lion so as to touch at a single point. The wires were twisted up to 360 degrees at the crossing point. The number and size of Al and Mg wires were varied in order to optimize the K-shell line radiation. Diagnostics used for the experiments included pinhole photography, streak imaging, filtered photoconducting diodes and x-ray crystal spectroscopy. The source size and distribution are determined through x-ray pinhole photographs. The radiation energy spectrum is determined by x-ray spectroscopy and attenuation through filters. Energy intensities were obtained from the filtered photoconducting diodes

  5. Light detonation wave in a cylindrical Z-pinch

    Science.gov (United States)

    Yusupaliev, U.; Sysoev, N. N.; Shuteev, S. A.; Elenskii, V. G.

    2015-09-01

    A secondary compression wave previously observed by other researchers in a cylindrical Z-pinch has been identified in this work as a light detonation wave. It appears on the inner surface of a discharge chamber under the action of the intense ultraviolet radiation from a plasma pinch at the stage of its maximum compression. The condition of the light detonation wave has been determined experimentally. The dependence of its Mach number on a generalized dimensionless variable has been determined taking into account the conservation laws for the light detonation wave including the pressure of the gas, expenses on the formation of the surface plasma, and the energy of ionization of the gas involved in the wave. An analogy with the laser-supported detonation wave created by intense laser radiation has been revealed. The indicated dependence is within the error of measurement in agreement with the experimental data for light detonation waves created by both methods.

  6. A theta-pinch as a spectroscopic light source

    Energy Technology Data Exchange (ETDEWEB)

    Luna, F.R.T.; Trigueiros, A.G. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Fisica; Cavalcanti, G.H. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Fisica

    1998-12-31

    The aim of this work is to describe a theta-pinch for spectroscopic studies. This machine is different in some aspects from its equivalent for fusion studies. Here, in a single experiment, 1000 shots are used normally. The capacitor bank stores 14 kJ of electrical energy at 60 kV, but only 1 kJ is necessary to obtain an electron peak temperature of 150 eV, which is enough to produce a good emission spectrum in the VUV range of 300 to 2000 A. With this device it is possible to obtain intermediate ionization states of many elements (ionized six or seven times). Similarly to tokamaks, the theta-pinch spectrum contains spectral lines due to forbidden transitions, where the {delta}S = 0 rule for dipole electric transition is violated. (author) 8 refs., 6 figs., 1 tab.

  7. Energy integration of nitric acid production using pinch methodology

    OpenAIRE

    Ivaniš Gorica R.; Lazarević Marija; Radović Ivona R.; Kijevčanin Mirjana Lj.

    2015-01-01

    Pinch methodology was applied to the heat exchangers network (HEN) synthesis of nitric acid production. The integration is analyzed in two ways, and the results are presented as two different solutions: (i) the first solution is based on the original heat transfer equipment arrangement, (ii) in order to eliminate the shortages of the first solution the second HEN was obtained using process simulation with optimized process parameters. Optimized HEN, with ne...

  8. Schlieren measurements of a high density z-pinch

    International Nuclear Information System (INIS)

    The dense plasma phase of a dynamic z-pinch working at a high filling pressure is studied. By using the Schlieren-technique it is found that the compressed plasma column, though macroscopically stable for times less than 1 μs develops quickly from a homogeneous state to a turbulent one with a perturbation scale length of typically some millimeters. Quantitative measurements of light deflection give electron densities of typically 1019 cm-3 at 0.25 torr He filling. (orig.)

  9. Sausage mode of a pinched charged particle beam

    International Nuclear Information System (INIS)

    The axisymmetric oscillations of a self-pinched charged particle beam are analyzed using a dispersion relation derived from a 3/2 dimensional model. This calculation includes the effects of rounded profiles, finite conductivity, a steady return current, and phase mix damping among particle orbits. However, only the lowest order radial mode of distortion is treated, and this is done in an approximate fashion

  10. Hard-core deuterium fibre Z-pinch

    International Nuclear Information System (INIS)

    A novel fusion concept is considered, related to present day deuterium fibre pinch experiments. The hard core is allowed to persist during the discharge, being completely ablated only at the end of the pulse. The Lawson requirement ητΕ> 1022M-3s for the catalysed D-D reaction is exceeded at a plasma temperature >30 keV by using high power generators with short pulse times of order a few ns. (au)

  11. Pinched Material Einstein Space-Time Produces Accelerated Cosmic Expansion

    OpenAIRE

    M. S. El Naschie

    2014-01-01

    An instructive analogy between the deformation of a pinched elastic cylindrical shell and the anti-gravity behind accelerated cosmic expansion is established. Subsequently the entire model is interpreted in terms of a hyperbolic fractal Rindler space-time leading to the same robust results regarding real energy and dark energy being 4.5% and 95.5% respectively in full agreement with all recent cosmological measurements.

  12. Theory of the striated corona in a theta pinch

    International Nuclear Information System (INIS)

    The radial striations observed in the low density corona surrounding a theta-pinch-confined plasma are explained as due to an instability at the ion plasma frequency driven by plasma rotation in the corona. A nonlocal theory is used to find radially extended modes, as observed experimentally. The observed wavelength of the striations can then be used to deduce the density in this region; this density is in reasonable agreement with estimates from numerical models

  13. End shorting induced rotation in a theta pinch

    International Nuclear Information System (INIS)

    A possible explanation for the observed rotation in open ended theta-pinch devices is shown to result from the shorting out of electric field components at the insulating boundary. The propagation of rotation into the plasma is primarily via torsional Alfven waves preceded by dispersive precursors. The precursors have spatially and temporally modulated amplitudes. They are due to gyrofrequency oscillations of the plasma and are seen throughout the plasma immediately following the shorting out of the electric field components at the insulators

  14. Necessary stability condition for field-reversed theta pinches

    International Nuclear Information System (INIS)

    Toroidal systems of arbitrary cross section without toroidal magnetic field are analyzed via the double adiabatic fluid equations. Such systems are shown to be unstable if there exists one closed field line on which the average of kapparB2 is positive, where kappa is the curvature. A similar criterion is derived for linear systems and is applied to a noncircular z-pinch

  15. Necessary stability condition for field-reversed theta pinches

    Energy Technology Data Exchange (ETDEWEB)

    Cary, J. R.

    1981-03-01

    Toroidal systems of arbitrary cross section without toroidal magnetic field are analyzed via the double adiabatic fluid equations. Such systems are shown to be unstable if there exists one closed field line on which the average of kapparB/sup 2/ is positive, where kappa is the curvature. A similar criterion is derived for linear systems and is applied to a noncircular z-pinch.

  16. X-ray sources by Z-pinch for inertial confinement fusion

    International Nuclear Information System (INIS)

    Inertial confinement nuclear fusion driven by X-ray from Z-pinch plasmas has been developed. Recently, extremely high X-ray power (290 TW) and energy (1.8 MJ) were produced in fast Z-pinch implosions on the Z accelerator (Sandia National Laboratories). Wire arrays are used to produce the initial plasma. The X-ray from Z-pinch plasmas produced by pulsed power has great potential as a driver of inertial confinement nuclear fusion. (author)

  17. Effect of longitudinal applied magnetic field on the self-pinched critical current in intense electron beam diode

    Institute of Scientific and Technical Information of China (English)

    Liu Guo-Zhi; Huang Wen-Hua; Shao Hao; Xiao Ren-Zhen

    2006-01-01

    The effect of applied longitudinal magnetic field on the self-pinched critical current in the intense electron beam diode is discussed. The self-pinched critical current is derived and its validity is tested by numerical simulations. The results shows that an applied longitudinal magnetic field tends to increase the self-pinched critical current. Without the effect of anode plasma, the maximal diode current approximately equals the self-pinched critical current with the longitudinal magnetic field applied; when self-pinched occurs, the diode current approaches the self-pinched critical current.

  18. Grip and Pinch Strength Norms for Michigan Workers

    Directory of Open Access Journals (Sweden)

    Joel M. Phillips M.S., OTRL

    2013-06-01

    Full Text Available The purpose of this study was to create a norm reference of current grip and pinch strength norms for working-age Michigan adults. This normative study included a convenience sample of 179 volunteers who were employees at car plants in South East Michigan or hospital sites in West Michigan. Participants’ ages ranged from between 20 and 62 years of age with a mean age of 49.15 years. There were 78 females (44% and 101 males (56%. Subjects were classified by gender and in the age categories of ages 20 to 49 years and ages 50-62 years. Grip and pinch strength norms were collected following the American Society of Hand Therapy protocol. The norms from these working adults were calculated with descriptive statistics for males and females in two age classifications: ages 20 to 49 and ages 50 to 62 years. Standard Errors (SE are better than the 1985 norms for both males and females ages 20 to 49 years. SEs are higher than the ages 20 to 49 years’ norms for the ages 50 to 62 years age categories in both males and females. These norms offer a point of comparison for clinicians to use for clients in Michigan who are ages 20 to 62 years and who have a goal to improve their grip strength. Clients’ grip and pinch strength could be compared to their age level or gender norms using the comparison for one standard deviation above, below, or at the means.

  19. Diagnostics for Z-pinch implosion experiments on PTS

    Science.gov (United States)

    Ren, X. D.; Huang, X. B.; Zhou, S. T.; Zhang, S. Q.; Dan, J. K.; Li, J.; Cai, H. C.; Wang, K. L.; Ouyang, K.; Xu, Q.; Duan, S. C.; Chen, G. H.; Wang, M.; Feng, S. P.; Yang, L. B.; Xie, W. P.; Deng, J. J.

    2014-12-01

    The preliminary experiments of wire array implosion were performed on PTS, a 10 MA z-pinch driver with a 70 ns rise time. A set of diagnostics have been developed and fielded on PTS to study pinch physics and implosion dynamics of wire array. Radiated power measurement for soft x-rays was performed by multichannel filtered x-ray diode array, and flat spectral responses x-ray diode detector. Total x-ray yield was measured by a calibrated, unfiltered nickel bolometer which was also used to obtain pinch power. Multiple time-gated pinhole cameras were used to produce spatial-resolved images of x-ray self-emission from plasmas. Two time-integrated pinhole cameras were used respectively with 20-μm Be filter and with multilayer mirrors to record images produced by >1-keV and 277±5 eV self-emission. An optical streak camera was used to produce radial implosion trajectories, and an x-ray streak camera paired with a horizontal slit was used to record a continuous time-history of emission with one-dimensional spatial resolution. A frequency-doubled Nd:YAG laser (532 nm) was used to produce four frame laser shadowgraph images with 6 ns time interval. We will briefly describe each of these diagnostics and present some typical results from them.

  20. Radiating Shock Properties in the Z-pinch Dynamic Hohlraum

    International Nuclear Information System (INIS)

    The Z-pinch dynamic hohlraum is a high-power x-ray source used for a variety of high energy-density physics applications including high temperature opacity measurements and inertial confinement fusion (ICF). The system consists of a tungsten wire-array Z pinch that implodes onto a low-density CH2 foam launching a radiating shock that heats the hohlraum to radiation temperatures >200 eV. The temperature and density evolution of this shock have been inferred through the measurement of time- and space-resolved line emission from Si atoms locally doped in the CH2 foam. The observed emission spectra are analyzed through comparison to collisional-radiative calculations that include a detailed treatment of line-shapes and the effect of non-local radiation on the atomic level populations. As a complement to the detailed spectral data, the radial and azimuthal distribution of the axially directed shock emission is recorded with time-gated x-ray pinhole images that provide information on the spatial profile of the shock conditions. Together with broadband x-ray power measurements, these data provide a comprehensive suite of information to determine the shock dynamics and associated energetics of the Z-pinch dynamic hohlraum.

  1. Diagnostics for Z-pinch implosion experiments on PTS

    Energy Technology Data Exchange (ETDEWEB)

    Ren, X. D., E-mail: amosrxd@163.com; Huang, X. B., E-mail: amosrxd@163.com; Zhou, S. T., E-mail: amosrxd@163.com; Zhang, S. Q., E-mail: amosrxd@163.com; Dan, J. K., E-mail: amosrxd@163.com; Li, J., E-mail: amosrxd@163.com; Cai, H. C., E-mail: amosrxd@163.com; Wang, K. L., E-mail: amosrxd@163.com; Ouyang, K., E-mail: amosrxd@163.com; Xu, Q., E-mail: amosrxd@163.com; Duan, S. C., E-mail: amosrxd@163.com; Chen, G. H., E-mail: amosrxd@163.com; Wang, M., E-mail: amosrxd@163.com; Feng, S. P., E-mail: amosrxd@163.com; Yang, L. B., E-mail: amosrxd@163.com; Xie, W. P., E-mail: amosrxd@163.com; Deng, J. J., E-mail: amosrxd@163.com [Key Lab of Pulsed Power, Institute of Fluid Physics, CAEP, P.O. Box 919-108, Mianyang, Sichuan 621999 (China)

    2014-12-15

    The preliminary experiments of wire array implosion were performed on PTS, a 10 MA z-pinch driver with a 70 ns rise time. A set of diagnostics have been developed and fielded on PTS to study pinch physics and implosion dynamics of wire array. Radiated power measurement for soft x-rays was performed by multichannel filtered x-ray diode array, and flat spectral responses x-ray diode detector. Total x-ray yield was measured by a calibrated, unfiltered nickel bolometer which was also used to obtain pinch power. Multiple time-gated pinhole cameras were used to produce spatial-resolved images of x-ray self-emission from plasmas. Two time-integrated pinhole cameras were used respectively with 20-μm Be filter and with multilayer mirrors to record images produced by >1-keV and 277±5 eV self-emission. An optical streak camera was used to produce radial implosion trajectories, and an x-ray streak camera paired with a horizontal slit was used to record a continuous time-history of emission with one-dimensional spatial resolution. A frequency-doubled Nd:YAG laser (532 nm) was used to produce four frame laser shadowgraph images with 6 ns time interval. We will briefly describe each of these diagnostics and present some typical results from them.

  2. ANALISIS CITRA PERMUKAAN THERMOCHROMIC LIQUID CRYSTAL BERDASARKAN NILAI STATISTIK HUE

    Directory of Open Access Journals (Sweden)

    Risti Suryantari

    2014-05-01

    Full Text Available Tujuan dari penelitian ini adalah untuk mengamati perbedaan citra pada permukaan Thermocromic Liquid Crystal (TLC R25C5W akibat perubahan temperatur. Metode yang digunakan untuk analisis adalah pengolahan citra berbasis morfologi matematika menggunakan perangkat lunak Matlab2013a. Citra asli yang diperoleh dalam bentuk RGB dikonversi menjadi HSV (hue, saturation, value, dengan mengambil komponen hue saja. Proses utama yang digunakan adalah opening dengan struktur elemen (SE line. Berdasarkan analisis visual pada citra akhir hasil pengolahan citra, tampak bahwa terdapat perbedaan setiap citra untuk berbagai temperatur berdasarkan tingkat kecerahannya. Secara kuantitatif perbedaan tersebut dapat dilihat dari nilai statistiknya. Nilai max dan mean citra hue semakin meningkat seiring dengan meningkatnya temperatur.

  3. The Prospects for High-Yield ICF with a Z-Pinch Driven Dynamic Hohlraum

    Energy Technology Data Exchange (ETDEWEB)

    CHANDLER, GORDON A.; CHRIEN, R.; COOPER, GARY WAYNE; DERZON, MARK S.; DOUGLAS, MELISSA R.; HEBRON, DAVID E.; LASH, JOEL S.; LEEPER, RAMON J.; MATZEN, M. KEITH; MEHLHORN, THOMAS A.; NASH, THOMAS J.; OLSON, RICHARD E.; PETERSON, D.L.; RUIZ, CARLOS L.; SANFORD, THOMAS W. L.; SLUTZ, STEPHEN A.

    1999-09-07

    Recent success with the Sandia Z machine has renewed interest in utilizing fast z-pinenes for ICF. One promising concept places the ICF capsule internal to the imploding z-pinch. At machine parameters relevant to achieving high yield, the imploding z-pinch mass has sufficient opacity to trap radiation giving rise to a dynamic hohlraum. The concept utilizes a 12 MJ, 54 MA z-pinch driver producing a capsule drive temperature exceeding 300 eV to realize a 550 MJ thermonuclear yield. They present the current high-yield design and its development that supports high-yield ICF with a z-pinch driven dynamic hohlraum.

  4. The Prospects for High-Yield ICF with a Z-Pinch Driven Dynamic Hohlraum

    International Nuclear Information System (INIS)

    Recent success with the Sandia Z machine has renewed interest in utilizing fast z-pinenes for ICF. One promising concept places the ICF capsule internal to the imploding z-pinch. At machine parameters relevant to achieving high yield, the imploding z-pinch mass has sufficient opacity to trap radiation giving rise to a dynamic hohlraum. The concept utilizes a 12 MJ, 54 MA z-pinch driver producing a capsule drive temperature exceeding 300 eV to realize a 550 MJ thermonuclear yield. They present the current high-yield design and its development that supports high-yield ICF with a z-pinch driven dynamic hohlraum

  5. Developing models for simulation of pinched-beam dynamics in heavy ion fusion. Revision 1

    International Nuclear Information System (INIS)

    For heavy-ion fusion energy applications, Mark and Yu have derived hydrodynamic models for numerical simulation of energetic pinched-beams including self-pinches and external-current pinches. These pinched-beams are applicable to beam propagation in fusion chambers and to the US High Temperature Experiment. The closure of the Mark-Yu model is obtained with adiabatic assumptions mathematically analogous to those of Chew, Goldberger, and Low for MHD. Features of this hydrodynamic beam model are compared with a kinetic treatment

  6. Influence of an external circuit on the pinch time in argon-filled capillary Z-pinch

    International Nuclear Information System (INIS)

    In this paper, we present a theoretical and experimental study on a capillary discharge for soft X-ray lasers. The theoretical analysis is based on the so called '' snow-plow '' model. By this model, it is possible to calculate pinch time as a function of current, gas pressure, tube diameter, discharge capacitance and inductance. In laboratory we have used table-top argon filled soft X-ray laser. By use of this machine, one can change the current from 10 kA to 35 kA, argon gas pressure from 100 mTorr to 800 mTorr. The laser output pulse was detected by an XRD. The calculated and measured results of pinch time are compared. (author)

  7. ANALISIS CITRA PERMUKAAN THERMOCHROMIC LIQUID CRYSTAL BERDASARKAN NILAI STATISTIK HUE

    OpenAIRE

    Risti Suryantari; - Flaviana

    2014-01-01

    Tujuan dari penelitian ini adalah untuk mengamati perbedaan citra pada permukaan Thermocromic Liquid Crystal (TLC) R25C5W akibat perubahan temperatur. Metode yang digunakan untuk analisis adalah pengolahan citra berbasis morfologi matematika menggunakan perangkat lunak Matlab2013a. Citra asli yang diperoleh dalam bentuk RGB dikonversi menjadi HSV (hue, saturation, value), dengan mengambil komponen hue saja. Proses utama yang digunakan adalah opening dengan struktur elemen (SE) line. Berdasark...

  8. Analisis Tema Pada Pantun Melayu, Suatu Kajian Fungsional Sistematik

    OpenAIRE

    Desri Wiyana

    2008-01-01

    Tujuan penelitian ini adalah mendeskripsikan tema yang terdapat pada pantun-pantun Melayu yang di dalam penelitian ini hanya dibatasi pada tiga jenis pantun Melayu, yaitu pantun percintaan, pantun jenaka dan pantun kias. Penelitian ini juga mendeskripsikan tema dan unsur-unsur yang paling dominan kehadirannya di dalam tiga jenis pantun tersebut. Data diambil dari buku karangan T. Luckman Sinar, S.H. yang berjudul "Pantun dan Pepatah Melayu". Metode analisis data dilakukan dengan pendekatan Te...

  9. MODEL TES DAN ANALISIS PRESTASI BELAJAR MATEMATIK SISWA SEKOLAH DASAR

    OpenAIRE

    Zamsir Zamsir

    2013-01-01

    Penelitian ini bertujuan untuk menemukan model tes dan analisis prestasi belajar siswa yang dapat dipakai untuk melakukan identifikasi level kemampuan dan menyusun profil pencapaian kompetensi siswa, khususnya di sekolah dasar. Penelitian ini merupakan penelitian pengembangan model yang dikembangkan menyangkut dua hal, yaitu: (1) prosedur dan langkah-langkah penyusunan tes serta teknik identifikasi level kemampuan siswa, dan (2) pelaporan hasil tes. Identifikasi dilakukan dengan cara menempat...

  10. Analysis of the temperature field of an instrument's guard to measure the thermal conductivity of insulating solid materials; Analisis del campo de temperatura de la guarda de un instrumento para medir la conductividad termica de materiales solidos aislantes

    Energy Technology Data Exchange (ETDEWEB)

    Lira Cortes, Leonel; Xaman Villasenor, Jesus P; Chavez Chena Yvonne [CENIDET: Centro Nacional de Investigacion y Desarrollo Tecnologico, Cuernavaca, Morelos(Mexico)

    2000-07-01

    In this paper the analysis of the temperature field of the guard of an instrument called hot plate apparatus with guard (APCG), is presented. The experimental results are compared against the ones that are obtained when solving the problem in analytical form. In the analytical solution the influence of taking into account more than one own value is analyzed and the results when truncating in the first term of sum that corresponds to the first own value and to truncate in the second term that includes the first and second root are compared. The instrument is a parallel flat plate apparatus with guards of 305 mm of diameter and operates in an interval of 10 to 80 of temperature and can measure insulating samples with a maximum thickness of 75 mm with a class of exactness of 4%. In applications of calculation of thermal loads, it is necessary to know the thermal conductivity of insulating and construction materials, when the applications are oriented to the use of renewable energies such as the solar, with the purpose of making an efficient use of this energy. [Spanish] En este trabajo se presenta el analisis del campo de temperatura de la guarda de un instrumento denominado aparato de placa caliente con guarda (APCG). Se comparan los resultados experimentales contra los que se obtienen al resolver el problema en forma analitica. En la solucion analitica se analiza la influencia de tomar en cuenta mas de un valor propio y se comparan los resultados al truncar en el primer termino de la sumatoria que corresponde al primer valor propio y truncar en el segundo termino que incluye la primera y segunda raiz. El instrumento es un aparato de platos planos paralelos con guardas de 305 mm de diametro y opera en un intervalo de 10 a 800 grados Celsius de temperatura y puede medir muestras aislantes con un maximo de espesor de 75 mm con una clase de exactitud del 4%. En aplicaciones del calculo de cargas termicas, es necesario conocer la conductividad termica de materiales

  11. ANALISIS PELAYANAN KB MANDIRI WANITA USIA SUBUR BERDASARKAN STATUS EKONOMI

    Directory of Open Access Journals (Sweden)

    Selma Siahaan

    2013-08-01

    Full Text Available Latar belakang: Penggunaan metode keluarga berencana (KB oleh Wanita Usia Subur (WUS antara lain dipengaruhi oleh faktor sosial ekonomi. Maka, masalah biaya yang harus dibayar oleh WUS untuk memperoleh pelayanan KB perludi pahami guna keberhasilan program KB Nasional. Metode: Studi menggunakan data Riset Kesehatan Dasar (Riskesdas 2010, bertujuan untuk mengetahui biaya pelayanan KB yang dibayar oleh perempuan usia 10–59 tahun (WUS yang pernah kawin menurut metode KB berdasarkan status ekonomi yang bersangkutan. Analisis data menggunakan analisis deskriptif, analisis bivariat dengan uji statistik chi-square. Hasil: Alat/obat KB disposible terbanyak yang digunakan WUS dari semua golongan status ekonomi adalah metode KB suntik, sedangkan kondom terbanyak digunakan oleh WUS dengan status ekonomi atas banyak. Sekitar 50% WUS dengan status ekonomi (SE rendah membayar biaya pelayanan KB berkisar Rp.10.000–Rp.15.000. Sementara itu WUS dengan SE atas terbanyak membayar sekitar > Rp. 20.000. Terdapat korelasi signifikan antara metode KB dengan biaya dan status ekonomi. Kesimpulan: Metode suntik masih merupakan metode pilihan bagi WUS di Indonesia dan pemilihan metode KB oleh WUS berhubungan dengan status ekonomi mereka. Oleh karena itu promosi kesehatan perlu terus digalakkan agar program KB pemerintah dengan IUD dapat lebih dikenal dan dapat diterima masyarakat. Di samping itu, diperlukan kebijakan khusus (bantuan kepada WUS dengan status ekonomi rendah sehingga IUD dapat diperoleh secara gratis atau setidaknya dengan biaya yang terjangkau.

  12. High energy density Z-pinch plasmas using flow stabilization

    International Nuclear Information System (INIS)

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and

  13. High energy density Z-pinch plasmas using flow stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Shumlak, U., E-mail: shumlak@uw.edu; Golingo, R. P., E-mail: shumlak@uw.edu; Nelson, B. A., E-mail: shumlak@uw.edu; Bowers, C. A., E-mail: shumlak@uw.edu; Doty, S. A., E-mail: shumlak@uw.edu; Forbes, E. G., E-mail: shumlak@uw.edu; Hughes, M. C., E-mail: shumlak@uw.edu; Kim, B., E-mail: shumlak@uw.edu; Knecht, S. D., E-mail: shumlak@uw.edu; Lambert, K. K., E-mail: shumlak@uw.edu; Lowrie, W., E-mail: shumlak@uw.edu; Ross, M. P., E-mail: shumlak@uw.edu; Weed, J. R., E-mail: shumlak@uw.edu [Aerospace and Energetics Research Program, University of Washington, Seattle, Washington, 98195-2250 (United States)

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and

  14. Polycrystalline diamond based detector for Z-pinch diagnosis

    International Nuclear Information System (INIS)

    Full text of publication follows: Z-pinch is a self-constricted plasma configuration, as well as a high efficient X-ray simulator with energy transfer coefficient in the range of 0.8% - 23% [1-4]. Characteristics of the X-ray from Z-pinch are very important for researches focusing on the physical processes of plasma [5-6]. A chemical vapour deposition (CVD) derived polycrystalline diamond film detector has been developed as the X-ray detector on Z-pinch at a high powerful pulsed electron beam accelerator named Qiangguang-I (current 1.4-2.1 MA, rising time 80-100 ns) in Northwest Institute of Nuclear Technology in P. R. China. This detector is 16 mm in diameter and 300 μm in thickness with gold electrodes on both sides. The dark current of the detector is lower than 60 pA with the electric field intensity of 3 V/μm. The charge collection efficiency is 60.8% with the electric field intensity of 1.67 V/μm. The energy response and the time response have been studied by both experiments and theoretical calculation. The spectral response to X-ray is flat over the range of 3-5 keV. The rising time of response pulse is 2-3 ns. This diamond detector acquires good experimental data which are in good agreement with the results got from the X-ray Diodes (XRDs) [7] on Z-pinch diagnosis at Qiangguang-I facility. These results show that the device we developed offers a good choice for Z-pinch diagnosis at high power electron beam accelerator. References: [1] R. B. Spielman, C. Deeney and G. A. Chandler, Phys of Plasmas 5, 5 (1998); [2] Proceedings of 10. IEEE International Pulsed Power Conference 1995, 1-2; [3] Proceedings of 11. IEEE International Pulsed Power Conference 1997, 23-36; [4] A. Qiu, Engineering Science 2, 9(2000); [5] A. Qiu, B. Kuai and Z. Zeng, Acta Physica Sinica 55, 11 (2006); [6] W. Wang, D. He and A. Qiu, High Power Laser and Particle Beams 15, 184(2003); [7] G. A. Chandler, C. Deeney and M. Cuneo, Review of Scientific Instruments 70, 1(1999). (authors)

  15. Self-pinched transport of intense ion beams

    International Nuclear Information System (INIS)

    Electron beams with substantial net currents have been routinely propagated in the self-pinched mode for the past two decades. However, as the physics of gas breakdown and beam neutralization is different for ion beams, previous predictions indicated insufficient net current for pinching so that ion beam self-pinched transport (SPT) was assumed impossible. Nevertheless, recent numerical simulations using the IPROP code have suggested that ion SPT is possible. These results have prompted initial experiments to investigate SPT of ion beams. A 100-kA, 1.2-MeV, 3-cm-radius proton beam, generated on the Gamble II pulsed-power accelerator at NRL, has been injected into helium in the 30- to 250-mTorr regime to study this phenomenon. Evidence of self-pinched ion beam transport was observed in the 35- to 80-mTorr SPT pressure window predicted by IPROP. Measured signals from a time- and space-resolved scattered proton diagnostic and a time-integrated Li(Cu) nuclear activation diagnostic, both of which measure protons striking a 10-cm diameter target 50 cm into the transport region, are significantly larger in this pressure window than expected for ballistic transport. These results are consistent with significant self-magnetic fields and self-pinching of the ion beam. On the other hand, time-integrated signals from these same two diagnostics are consistent with ballistic transport at pressures above and below the SPT window. Interferometric electron line-density measurements, acquired during beam injection into the helium gas, show insignificant ionization below 35 mTorr, a rapidly rising ionization fraction with pressure in the SPT window, and a plateau in ionization fraction at about 2% for pressures above 80 mTorr. These and other results are consistent with the physical picture for SPT. IPROP simulations, which closely model the Gamble II experimental conditions, produce results that are in qualitative agreement with the experimental results. The advantages of SPT for

  16. Critical analysis of the daylight saving time; Analisis critico al horario del verano

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes Rubio, Hernando [Universidad Autonoma Metropolitana Ciudad-Ixtapalapa, Mexico, D.F., (Mexico)

    2001-07-01

    The critical analysis is presented as a synthesis of the problem untied since the implementation of the daylight saving time. The often related history is retaken to introduce the reader into the context of the causes of a such program. The geometric aspect of the solar trajectories is discussed and the length of the day as a function of the latitude and the time of the year to have technical elements for the time displacement in a certain region. The technical implementation of the daylight saving time based on three elements is justified: time of dawn and the decline (length of the day), national economic motivation and tourism industry. Stands out that although the daylight saving time schedule has a set of social and economic benefits it is not centered in the individual but in the society as a whole. The errors in handling the information and the misinformation are pointed out as the main causes of the controversy, the discord and the political manipulation of competing groups. [Spanish] El analisis critico se presenta como una sintesis del problema desatado desde la implementacion del horario de verano. La historia muchas veces contada se retoma para introducir al lector en el contexto de las causas de un tal programa. Se discute el aspecto geometrico de las trayectorias solares y la longitud del dia como una funcion de la latitud y de la epoca del ano para tener elementos tecnicos para el desplazamiento horario en una region determinada. Se justifica la implementacion tecnica del horario de verano en funcion de tres elementos: hora de alba y del ocaso (longitud del dia), motivacion economica nacional e industria turistica. Se destaca que si bien el horario de verano tiene un conjunto de beneficios sociales y economicos no se centra en el individuo sino en la sociedad en su conjunto. Se senalan los errores de manejo de la informacion y la desinformacion como los principales causantes de la polemica, el desacuerdo y la manipulacion politica de grupos

  17. PINCH1 is transcriptional regulator in podocytes that interacts with WT1 and represses podocalyxin expression.

    Directory of Open Access Journals (Sweden)

    Dan Wang

    Full Text Available BACKGROUND: PINCH1, an adaptor protein containing five LIM domains, plays an important role in regulating the integrin-mediated cell adhesion, migration and epithelial-mesenchymal transition. PINCH1 is induced in the fibrotic kidney after injury, and it primarily localizes at the sites of focal adhesion. Whether it can translocate to the nucleus and directly participate in gene regulation is completely unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using cultured glomerular podocytes as a model system, we show that PINCH1 expression was induced by TGF-β1, a fibrogenic cytokine that promotes podocyte dysfunction. Interestingly, increased PINCH1 not only localized at the sites of focal adhesions, but also underwent nuclear translocation after TGF-β1 stimulation. This nuclear translocation of PINCH1 was apparently dependent on the putative nuclear export/localization signals (NES/NLS at its C-terminus, as deletion or site-directed mutations abolished its nuclear shuttling. Co-immunoprecipitation and pull-down experiments revealed that PINCH1 interacted with Wilms tumor 1 protein (WT1, a nuclear transcription factor that is essential for regulating podocyte-specific gene expression in adult kidney. Interaction of PINCH1 and WT1 was mediated by the LIM1 domain of PINCH1 and C-terminal zinc-finger domain of WT1, which led to the suppression of the WT1-mediated podocalyxin expression in podocytes. PINCH1 also repressed podocalyxin gene transcription in a promoter-luciferase reporter assay. CONCLUSION/SIGNIFICANCE: These results indicate that PINCH1 can shuttle into the nucleus from cytoplasm in podocytes, wherein it interacts with WT1 and suppresses podocyte-specific gene expression. Our studies reveal a previously unrecognized, novel function of PINCH1, in which it acts as a transcriptional regulator through controlling specific gene expression.

  18. Analysis of the potencial of natural illumination for the savings and efficient use of the energy in buildings located in hot climates; Analisis del potencial de la iluminacion natural para ahorro y uso eficiente de la energia en las edificaciones en climas calidos

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Chavez, J. R. [Universidad Autonoma Metropolitana-Azcapotzalco, Division de Ciencias y Artes para el Diseno, Departamento de Medio Ambiente, (Mexico)

    1997-12-31

    Daylight is an essential factor in lightening buildings. Its use is not only oriented to supply illumination to the spaces to provide adequate lightening levels for the optimum execution of their occupants` tasks, but also to supply the appropriate illumination level required in each case for specific functions, as well as to contribute to the psychophysiological health of its users and provide a favorable ambient and the germicide action in the ultraviolet component of the sunlight and besides a portion of vitamin {sup D,} that is needed for people`s health. On the other hand, the rational and efficient use of daylight can contribute to the diminish the consumption of electric power, that is used for the artificial lightning of buildings. This situation is particularly important in hot climates, where the consumption of electricity for lightening interior spaces is huge, mainly in non-dwelling buildings. In this paper the possibilities of the utilization of daylight are explored and analyzed for the purpose of achieving energy savings and the visual thermal and lightning comfort in buildings. [Espanol] La luz natural diurna es un factor indispensable en los edificios. Su uso no solamente esta orientado a proveer de iluminacion a los espacios para proporcionar niveles de iluminancia adecuados para la optima realizacion de las tareas visuales de los ocupantes, sino tambien para proporcionar la calidad luminica que se requiere para cada caso y funcion especificas, asi como contribuir a la salud psicofisiologica de los usuarios al brindarles un ambiente favorable y la accion germicida en la componente ultravioleta luminica y ademas, un contenido de vitamina {sup D,} necesario para la salud de las personas. Por otra parte, el uso sensato y eficiente de la luz natural diurna puede contribuir a reducir el consumo de energia electrica que se utiliza para el alumbrado artificial de los edificios. Esta situacion es de particular importancia en climas calidos, donde los

  19. Rancang Bangun Sistem Informasi Manajemen Customisable Sebagai Alat Analisis Pengelolaan Energi Listrik Di Pt. Indovillas Bali

    Directory of Open Access Journals (Sweden)

    I Made Sukafona

    2013-06-01

    Full Text Available Sistem informasi manajemen customizable sebagai alat analisis pengelolaan energi listrik di PT. Indovillas Bali merupakan suatu alat yang digunakan untuk mengelola data penggunaan energi listrik. Sistem customizable yaitu dapat disesuaikan dengan keadaan dimasing-masing vila, alur dan kebutuhan sistem dibuat dinamis agar dapat disesuaikan dengan keadaan. Dalam sistem terdapat sub-sub sistem berdasarkan para pengguna sistem yang memiliki database yang terpisah dengan hak akses sesuai dengan otoritas yang diberikan sistem. Hasil yang diharapkan dari sistem adalah report pengelolaan energi listrik yang terdiri dari  report penggunaan secara keseluruhan yang meliputi besaran konsumsi energi listrik setiap hari. Tingkat hunian kamar, serta batasan-batasan penggunaan energi listrik sebagai indikator perbandingan dengan data konsumsi energi listrik per hari Setiap bulan. Sistem juga diharapkan dapat menghasilkan potensi penghematan dari konsumsi energi listrik. Hasil dari keluaran sistem diharapkan dapat menjadi acuan utama  bagi manajer energi atau engineer dalam menentukan langkah-langkah yang tepat dalam penggunaan energi listrik yang efisien dan efektif. Bagi top manajemen, laporan ini diharapkan dapat menjadi bahan pertimbangan dalam menentukan harga sewa vila, dan memberikan informasi lebih terperinci tentang biaya konsumsi energi dalam pertanggungjawaban kepada pemilik vila.

  20. Recent developments in linear theta-pinch research: experiment and theory

    Energy Technology Data Exchange (ETDEWEB)

    McKenna, K.F.; Bartsch, R.R.; Commisso, R.J.

    1978-01-01

    High energy plasmas offusion interest can be generated in linear theta pinches. However, end losses present a fundamental limitation on the plasma containment time. This paper discusses recent progress in end-loss and end-stoppering experiments and in the theoretical understanding of linear theta-pinch physics.

  1. Generation of ultra-high magnetic fields by a degenerate, snow-plow pinch

    Science.gov (United States)

    Hartman, C. W.; Eddleman, J. L.; Gee, M.; Harte, J. A.; Zimmerman, G. B.

    1992-12-01

    We discuss 1-D and 2-D LASNEX calculations of a snow-plow pinch in Xenon. The pinch is driven by inductively stored energy, switched by a compact-torus, fast-opening switch, with performance characteristics calculated by the TRACII, 2-D, MHD code. The 10-cm initial radius, 1 cm long Xe pinch, is driven by 50 MA current thatis switched on in 100 ns. The pinch uniquely undergoes radiative collapse during the snow-plow phase, conforming to the original description of the 'snow-plow', to form a high-density, high-kinetic energy Xe shell which dynamically converges to a pinch equilibrium with degenerate electron pressure, high-density high-magnetic field. The described pinch configuration, calculated in 1-D, is expected to be unstable to R-T, sausage, and kink instabilities. A small initial B(sub zo) field (approximately 100 G) is calculated to be compressed to B(sub z) approximately = B (sub theta) at the final, degenerate, pinch equilibrium, thus stabilizing sausage instability. A larger initial B(sub z) field (approximately 10 kG) is calculated to be compressed by the radiatively collapsing plasma in the snow-plow to B(sub z) approximately = B (sub theta) to stabilize R-T instability during the snow-plow phase. Finally, the kink instability (if it occurs) is expected, as observed, to leave intact the tightly pinched plasma column.

  2. Nonlinear development of the sausage instability in dense Z-pinches

    International Nuclear Information System (INIS)

    In this paper, a 2d envelope model is described for the nonlinear development of the sausage instability in dense Z-pinches. Numerical solutions for various cases of interest are provided which lay the foundation for a quantitative model of nonthermal neutron emission in dense Z-pinches by determining the induced electric fields associated with the development of the instability

  3. On the kink stability of a linear extrap pinch

    International Nuclear Information System (INIS)

    With the main purpose of identifying and illustrating the relevant stabilizing and destabilizing mechanisms in a linear Z-pinch of 'Extrap' type, an analysis has been made on the particular case of plane incompressible kink modes. In this pinch there is a superimposed transverse inhomogeneous magnetic field B sub V, produced by currents in a set of external conductor rods. A modified form of the energy principle has been used which takes explicit account of induced surface currents. The stabilizing mechanisms are found to be due to induced surface currents in presence of the transverse field B sub V, to induced colume currents in presence of B sub V, and to volume currents induced by inhomogeneous motion in the field B sub p generated by the pinch current. Further, a cross-effect between B sub V and B sub p leads to destabilizing or stabilizing contributions depending on the orientation of the kink plane. Finally, there is a main destabilizing effect from the conventional kink force. As compared to all other mechanisms, the stabilizing effect of induced surface currents on free-surface kink modes becomes very strong at long wave lengths Λ. There are certain optimal parameter values, such as for plasmas which extend almost out to the magnetic separatrix, for which stability can be achieved for all wave lengths Λ. A new non-MHD mechanism has been predicted which is based on deviations from constancy of the second adiabatic invariant, and which may secure stability at small and intermediate wave lengths Λ. (author)

  4. Z-Pinch fusion-based nuclear propulsion

    Science.gov (United States)

    Miernik, J.; Statham, G.; Fabisinski, L.; Maples, C. D.; Adams, R.; Polsgrove, T.; Fincher, S.; Cassibry, J.; Cortez, R.; Turner, M.; Percy, T.

    2013-02-01

    Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Due to the great distances between the planets of our solar system and the harmful radiation environment of interplanetary space, high specific impulse (Isp) propulsion in vehicles with high payload mass fractions must be developed to provide practical and safe vehicles for human space flight missions. The Z-Pinch dense plasma focus method is a Magneto-Inertial Fusion (MIF) approach that may potentially lead to a small, low cost fusion reactor/engine assembly [1]. Recent advancements in experimental and theoretical understanding of this concept suggest favorable scaling of fusion power output yield [2]. The magnetic field resulting from the large current compresses the plasma to fusion conditions, and this process can be pulsed over short timescales (10-6 s). This type of plasma formation is widely used in the field of Nuclear Weapons Effects testing in the defense industry, as well as in fusion energy research. A Z-Pinch propulsion concept was designed for a vehicle based on a previous fusion vehicle study called "Human Outer Planet Exploration" (HOPE), which used Magnetized Target Fusion (MTF) [3] propulsion. The reference mission is the transport of crew and cargo to Mars and back, with a reusable vehicle. The analysis of the Z-Pinch MIF propulsion system concludes that a 40-fold increase of Isp over chemical propulsion is predicted. An Isp of 19,436 s and thrust of 3812 N s/pulse, along with nearly doubling the predicted payload mass fraction, warrants further development of enabling technologies.

  5. Liner Compression of a MAGO / Inverse-Pinch Configuration

    Energy Technology Data Exchange (ETDEWEB)

    Siemon, R E; Atchison, W L; Awe, T; Bauer, B S; Buyko, A M; Chernyshev, V K; Cowan, T E; Degnan, J H; Faehl, R J; Fuelling, S; Garanin, S F; Goodrich, T; Ivanovsky, A V; Lindemuth, I R; Makhin, V; Mokhov, V N; Reinovsky, R E; Ryutov, D D; Scudder, D W; Taylor, T; Yakubov, V B

    2005-05-18

    In the ''metal liner'' approach to Magnetized Target Fusion (MTF), a preheated magnetized plasma target is compressed to thermonuclear temperature and high density by externally driving the implosion of a flux conserving metal enclosure, or liner, which contains the plasma target. As in inertial confinement fusion, the principle fusion fuel heating mechanism is pdV work by the imploding enclosure, called a pusher in ICF. One possible MTF target, the hard-core diffuse z pinch, has been studied in MAGO experiments at VNIIEF, and is one possible target being considered for experiments on the Atlas pulsed power facility. Numerical MHD simulations show two intriguing and helpful features of the diffuse z pinch with respect to compressional heating. First, in two-dimensional simulations the m=0 interchange modes, arising from an unstable pressure profile, result in turbulent motions and self-organization into a stable pressure profile. The turbulence also gives rise to convective thermal transport, but the level of turbulence saturates at a finite level, and simulations show substantial heating during liner compression despite the turbulence. The second helpful feature is that pressure profile evolution during compression tends towards improved stability rather than instability when analyzed according to the Kadomtsev criteria. A liner experiment is planned for Atlas to study compression of magnetic flux without plasma as a first step. The Atlas geometry is compatible with a diffuse z pinch, and simulations of possible future experiments show that keV temperatures and useful neutron production for diagnostic purposes should be possible if a suitable plasma injector is added to the Atlas facility.

  6. Z-pinch driven hohlraums design for the 100 nanoseconds current time scale

    International Nuclear Information System (INIS)

    This work estimates Z-pinch driven hohlraums capabilities to obtain high temperatures (>200 eV). Simple models are proposed to calculate the performances offered by currents of 5 to 100 MA in 100 ns. The one dimensional physics of the Z-pinch at the length scale of its thickness and the hydrodynamics instabilities are studied. Then the enhancement of hohlraums performances with double nested Z-pinches or the use of an axial magnetic field is analysed. Z-pinch direct drive approach for inertial confinement fusion is finally considered. All the presented results are based on theoretical and 2D numerical approach and on the analysis of experimental results which were obtained on the american 'Z' generator. Annexes recall radiation MHD equations and check their validity for Z-pinch implosion. (author)

  7. Development of sausage-type instability in a Z-pinch plasma column

    International Nuclear Information System (INIS)

    The development of sausage-type instabilities in an initially homogeneous Z-pinch plasma column has been investigated by means of numerical modelling. It is shown that in the presence of short-wave perturbations of a Z-pinch boundary and a rarefied plasma surrounding the pinch, cavities filled with a rarefied plasma and with a magnetic field are formed in the plasma column. As a result of this cavity growth, small columns of dense plasma form on the axis in the Z-pinch which have a temperature substantially higher than the average plasma temperature in the plasma column. When deuterium is present in the pinch, these dense high temperature bunches can become a source of intensive neutron radiation. (author). 24 refs, 7 figs

  8. Entropy production and inward heat pinch of plasma

    International Nuclear Information System (INIS)

    Heat pinch phenomena in the plasma with peripheral heating is discussed from the view point of thermodynamics. The entropy production rate associated with inward energy flow in the presence of energy exchange between electrons and ions is calculated. The inward energy flow can increase the total entropy production rate. It is conjectured that the outward energy flow of colder species (say ions) could sustain the energy flux of hotter species (say electrons) in the core, which flows into the direction of higher temperature. (author)

  9. Energy integration of nitric acid production using pinch methodology

    Directory of Open Access Journals (Sweden)

    Ivaniš Gorica R.

    2015-01-01

    Full Text Available Pinch methodology was applied to the heat exchangers network (HEN synthesis of nitric acid production. The integration is analyzed in two ways, and the results are presented as two different solutions: (i the first solution is based on the original heat transfer equipment arrangement, (ii in order to eliminate the shortages of the first solution the second HEN was obtained using process simulation with optimized process parameters. Optimized HEN, with new arrangement of heat exchangers, gave good results in energy and process optimization. [Projekat Ministarstva nauke Republike Srbije, br. P172063

  10. Magnetic Pinching of Hyperbolic Flux Tubes: I. Basic Estimations

    OpenAIRE

    Titov, V. S.; Galsgaard, K.; Neukirch, T.

    2002-01-01

    The concept of hyperbolic flux tubes (HFTs) is a generalization of the concept of separator field lines for coronal magnetic fields with a trivial magnetic topology. An effective mechanism of a current layer formation in HFTs is proposed. This mechanism is called magnetic pinching and it is caused by large-scale shearing motions applied to the photospheric feet of HFTs in a way as if trying to twist the HFT. It is shown that in the middle of an HFT such motions produce a hyperbolic flow that ...

  11. High yield fusion in a Staged Z-pinch

    OpenAIRE

    Rahman, H. U.; Wessel, F. J.; Rostoker, N.; Ney, P.

    2008-01-01

    We simulate fusion in a Z-pinch; where the load is a xenon-plasma liner imploding onto a deuterium-tritium plasma target and the driver is a 2 MJ, 17 MA, 95 ns risetime pulser. The implosion system is modeled using the dynamic, 2-1/2 D, radiation-MHD code, MACH2. During implosion a shock forms in the Xe liner, transporting current and energy radially inward. After collision with the DT, a secondary shock forms pre-heating the DT to several hundred eV. Adiabatic compression leads subsequently ...

  12. Capillary pinching discharge as water window radiation source

    Czech Academy of Sciences Publication Activity Database

    Vrba, Pavel; Vrbová, M.; Jančárek, A.; Nevrkla, M.; Tamáš, M.; Stefanovic, M.

    Cancún: Institute of Physics(IOP), 2009 - (Juárez Reyes, A.), PB15-5-PB15-5. (ICPIG. 29). ISBN N. [The 29th International Conference on Phenomena in Ionized Gases 2009. Cancún (MX), 12.07.2009-17.07.2009] R&D Projects: GA ČR GA102/07/0275 Grant ostatní: GA MŠk.(CZ) LC528 Institutional research plan: CEZ:AV0Z20430508 Keywords : Capillary Z-pinch * water window radiation source * RHMD Z* engine Subject RIV: BH - Optics, Masers, Lasers http://www.icpig2009.unam.mx

  13. Pinching Capillary Discharge as a Water Window Radiation Source

    Czech Academy of Sciences Publication Activity Database

    Vrba, Pavel; Zakharov, S.V.; Jančárek, A.; Vrbová, M.; Nevrkla, M.; Kolař, P.

    2011-01-01

    Roč. 184, 3-6 (2011), s. 335-337. ISSN 0368-2048. [The 37th International Conference on Vacuum Ultraviolet and X-ray Physics (VUVX2010). Vancouver, 11.07.2010-16.07.2010] R&D Projects: GA MŠk LA08024 Institutional research plan: CEZ:AV0Z20430508 Keywords : Capillary Z-pinch * water window radiation * soft x-ray spectral diagnostics * RHMD Z* engine Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.958, year: 2011 http://www.sciencedirect.com/science/article/pii/S0368204810002847

  14. 3-dimensional simulation of dynamo effect of reversed field pinch

    International Nuclear Information System (INIS)

    A non-linear numerical simulation of the dynamo effect of a reversed field pinch (RFP) with finite beta is presented. It is shown that the m=-1, n=(9,10,11,....,19) modes cause the dynamo effect and sustain the field reversed configuration. The role of the m=0 modes on the dynamo effect is carefully examined. Our simulation shows that the magnetic field fluctuation level scales as S-0.2 or S-0.3 in the range of 103 5, while Nebel, Caramana and Schnack obtained the fluctuation level is independent of S for a pressureless RFP plasma. (author)

  15. Burst of energetic ions from reversed field pinch plasma

    International Nuclear Information System (INIS)

    In a reversed field pinch (RFP), behavior of edge plasma is investigated by an energy analyzer and movable electrostatic probes scanning from the boundary of the core plasma to 122 mm outside in order to separate effects of ions and electrons. We clearly confirmed the behavior of the edge plasma and found that the energetic ions with a monochromatic energy distribution of about 3 keV were emitted from the core plasma. Its particle flux is 1017 - 1018 cm-2 sec-1. The energetic ion burst does not synchronize with the RFP dynamo. It is accompanied with the generation of the island overlapping. (author)

  16. Useful life consumption analysis of the blades of a gas turbine by thermofluency during constant load operation; Analisis de consumo de vida util por termofluencia en alabes de turbinas de gas durante operacion con carga constante

    Energy Technology Data Exchange (ETDEWEB)

    Ortega Quiroz, Gerardo Daniel

    2005-08-15

    A new analytical model for creep life prediction of gas turbine blades is proposed. The ultimate tensile strength is included to reflect heat-to-heat variations in strength. A thermo mechanical analysis is made using the finite element method. With the stress distribution obtained, some creep life prediction models as the Norton-Bailey and Dorn-Bailey models were reviewed as well as the Larson-Miller parameter. The time to failure data obtained with the previous analysis, was used to determine the new creep life prediction model coefficients. The results obtained are in good concordance with experimental data for IN-738-LN gas turbine blades. [Spanish] En el presente trabajo se propone un nuevo modelo analitico para predecir la vida util por termofluencia en alabes de turbinas de gas, donde se incluye el esfuerzo ultimo de tension para reflejar el efecto que tiene la variacion de la temperatura en la rigidez del material. Para lograr esto, primero se hizo un analisis termomecanico del alabe, utilizando el metodo de elementos finitos. Con los esfuerzos obtenidos, se hizo una revision de los modelos de consumo de vida de Norton-Bailey y de Dorn-Bailey. Tambien se utilizo el parametro Larson-Miller para obtener datos de consumo de vida. Con los resultados de los analisis anteriores, fue posible determinar los coeficientes del modelo propuesto. Los resultados obtenidos estan en buena concordancia con los datos experimentales del alabe, y muestran un error menor que el de los modelos revisados.

  17. Classical scaling laws of a Z-pinch with a cold-mantle

    International Nuclear Information System (INIS)

    Classical scaling laws are deduced for the equilibrium relations between pinch current J, pinch radius a, axial density n0 and temperature T0 of linear Z-pinches having a finite length L, as well as for toroidal Z-pinches having a large aspect ratio. In both cases the radius a is found to increase almost linearly with the current J at a fixed density n0, and the temperature T0 to increase with J at fixed values of the radius a. In principle, anomalous transport can be simulated in a first approximation by multiplying the transport coefficients by corresponding numerical factors. At a fixed density n0 and a fixed external conductor current of an Extrap pinch, the radius a is found to increase more rapidly with J than the radius of the magnetic separatrix. Within the range of increasing pinch currents there are therefore three regimes of an Extrap system. For small J the system becomes unstable in the conventional way of unstabilized Z-pinches. For intermediate values of J, the magnetic surfaces become deformed by the external conductor field, and the constraints of this field combine with FLR and cold-mantle effects to provide a macroscopically stable state. Finally, for sufficiently large currents J, i.e. when the pinch radius a approaches and even tends to exceed the separatrix radius, the system is expected to become ballooning unstable in regions of -bad- field line curvature. The present analysis thus provides relations between the basic pinch parameters which can be tested by experiments, and it also contributes to the understanding of Extrap stability in terms of increasing pinch currents. (author)

  18. The importance of EBIT data for Z-pinch plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Safronova, A S; Kantsyrev, V L; Neill, P; Safronova, U I; Fedin, D A; Ouart, N D; Yilmaz, M F; Osborne, G; Shrestha, I; Williamson, K; Hoppe, T; Harris, C; Beiersdorfer, P; Hansen, S

    2007-04-04

    The results from the last six years of x-ray spectroscopy and spectropolarimetry of high energy density Z-pinch plasmas complemented by experiments with the electron beam ion trap (EBIT) at the Lawrence Livermore National Laboratory (LLNL) are presented. The two topics discussed are the development of M-shell x-ray W spectroscopic diagnostics and K-shell Ti spectropolarimetry of Z-pinch plasmas. The main focus is on radiation from a specific load configuration called an 'X-pinch'. X-pinches are excellent sources for testing new spectral diagnostics and for atomic modelling because of the high density and temperature of the pinch plasmas, which scale from a few {micro}m to several mm in size. They offer a variety of load configurations, which differ in wire connections, number of wires, and wire materials. In this work the study of X-pinches with tungsten wires combined with wires from other, lower-Z materials is reported. Utilizing data produced with the LLNL EBIT at different energies of the electron beam the theoretical prediction of line positions and intensity of M-shell W spectra were tested and calibrated. Polarization-sensitive X-pinch experiments at the University of Nevada, Reno (UNR) provide experimental evidence for the existence of strong electron beams in Ti and Mo X-pinch plasmas and motivate the development of x-ray spectropolarimetry of Z-pinch plasmas. This diagnostic is based on the measurement of spectra recorded simultaneously by two spectrometers with different sensitivity to the linear polarization of the observed lines and compared with theoretical models of polarization-dependent spectra. Polarization-dependent K-shell spectra from Ti X-pinches are presented and compared with model calculations and with spectra generated by a quasi-Maxwellian electron beam at the LLNL EBIT-II electron beam ion trap.

  19. Progress in symmetric ICF capsule implosions and wire-array z-pinch source physics for double z-pinch driven hohlraums

    International Nuclear Information System (INIS)

    Over the last several years, rapid progress has been made evaluating the double-z-pinch indirect-drive, inertial confinement fusion (ICF) high-yield target concept (Hammer et al 1999 Phys. Plasmas 6 2129). We have demonstrated efficient coupling of radiation from two wire-array-driven primary hohlraums to a secondary hohlraum that is large enough to drive a high yield ICF capsule. The secondary hohlraum is irradiated from two sides by z-pinches to produce low odd-mode radiation asymmetry. This double-pinch source is driven from a single electrical power feed (Cuneo et al 2002 Phys. Rev. Lett. 88 215004) on the 20 MA Z accelerator. The double z-pinch has imploded ICF capsules with even-mode radiation symmetry of 3.1 ± 1.4% and to high capsule radial convergence ratios of 14-21 (Bennett et al 2002 Phys. Rev. Lett. 89 245002; Bennett et al 2003 Phys. Plasmas 10 3717; Vesey et al 2003 Phys. Plasmas 10 1854). Advances in wire-array physics at 20 MA are improving our understanding of z-pinch power scaling with increasing drive current. Techniques for shaping the z-pinch radiation pulse necessary for low adiabat capsule compression have also been demonstrated.

  20. Progress in symmetric ICF capsule implosions and wire-array z-pinch source physics for double z-pinch driven hohlraums.

    Energy Technology Data Exchange (ETDEWEB)

    Bliss, David Emery; Vesey, Roger Alan; Rambo, Patrick K.; Lebedev, Sergey V. (Blackett Laboratory, Imperial College, London, UK); Hanson, David L.; Nash, Thomas J.; Yu, Edmund P.; Matzen, Maurice Keith; Afeyan, Bedros B. (Polymath Research, Inc., Pleasanton, CA); Smith, Ian Craig; Stygar, William A.; Porter, John Larry, Jr.; Cuneo, Michael Edward; Bennett, Guy R.; Campbell, Robert B.; Sinars, Daniel Brian; Chittenden, Jeremy Paul (Blackett Laboratory, Imperial College, London, UK); Waisman, Eduardo Mario; Mehlhorn, Thomas Alan

    2005-07-01

    Over the last several years, rapid progress has been made evaluating the double-z-pinch indirect-drive, inertial confinement fusion (ICF) high-yield target concept (Hammer et al 1999 Phys. Plasmas 6 2129). We have demonstrated efficient coupling of radiation from two wire-array-driven primary hohlraums to a secondary hohlraum that is large enough to drive a high yield ICF capsule. The secondary hohlraum is irradiated from two sides by z-pinches to produce low odd-mode radiation asymmetry. This double-pinch source is driven from a single electrical power feed (Cuneo et al 2002 Phys. Rev. Lett. 88 215004) on the 20 MA Z accelerator. The double z-pinch has imploded ICF capsules with even-mode radiation symmetry of 3.1 {+-} 1.4% and to high capsule radial convergence ratios of 14-21 (Bennett et al 2002 Phys. Rev. Lett. 89 245002; Bennett et al 2003 Phys. Plasmas 10 3717; Vesey et al 2003 Phys. Plasmas 10 1854). Advances in wire-array physics at 20 MA are improving our understanding of z-pinch power scaling with increasing drive current. Techniques for shaping the z-pinch radiation pulse necessary for low adiabat capsule compression have also been demonstrated.

  1. La mineria en Galicia: analisis economico cuantitativo.

    OpenAIRE

    Rodriguez, X.A.

    1995-01-01

    Los romanos consideraban a Galicia como un "coto minero" de especial relevancia para el Imperio, por sus ricos yacimientos de oro, plata, hierro, cobre, estaño, plomo... que poblaban su territorio. En el contexto de las dos Guerras Mundiales, y con finalidades belicas, adquieren importante protagonismo las extracciones gallegas de wolframio y estaño. En la actualidad la "vocacion" minera de esta Comunidad, dentro de lo que se dio en llamar la "nueva mineria" (productos de cantera y minerales ...

  2. Analisis Karakteristik Yang Mempengaruhi Terciptanya Word Of Mouth Pada Usaha Es Dawet Cah Mbanjar Medan (Studi Kasus Pada Mahasiswa FISIP USU)

    OpenAIRE

    Ardiansyah, Muhammad

    2010-01-01

    Tujuan penelitian ini adalah untuk mengetahui dan menganalisis karakteristik yang mempengaruhi word of mouth pada Usaha Es Dawet Cah Mbanjar pada mahasiswa FISIP USU. Metode analisis yang digunakan untuk karakteristik yang mempengaruhi word of mouth pada Usaha Es Dawet Cah Mbanjar pada mahasiswa FISIP USU adalah Analisis Deskriptif dan Analisis Kuantitatif dengan Metode Regresi Linier Berganda (Multiple Linear Regression). Hasil penelitian menunjukkan bahwa dari hasil analisis deskriptif ...

  3. Accelerated Ions from a Laser Driven Z-pinch

    CERN Document Server

    Helle, Michael H; Kaganovich, Dmitri; Chen, Yu-hsin; Palastro, John P; Ting, Antonio

    2015-01-01

    Intense laser acceleration of ions is inherently difficult due to the velocity mismatch between laser pulses moving at the speed of light and slowly moving massive ions. Instead of directly accelerating the ions, current approaches rely on TV/m laser fields to ionize and drive out electrons. The ions are then accelerated by the resulting electrostatic fields from charge separation. Here we report experimental and numerical acceleration of ions by means of laser driven Z-pinch exiting a sharp plasma interface. This is achieved by first driving a plasma wakefield in the self-modulated bubble regime. Cold return currents are generated to maintain quasi-neutrality of the plasma. The opposite current repel and form an axial fast current and a cylindrical-shell cold return current with a large (100 MG) azithmuthal field in between. These conditions produce a Z-pinch that compresses the fast electrons and ions on axis. If this process is terminated at a sharp plasma interface, a beam of ions are then accelerated in ...

  4. Capillary breakup of suspensions near pinch-off

    Science.gov (United States)

    Mathues, Wouter; McIlroy, Claire; Harlen, Oliver G.; Clasen, Christian

    2015-09-01

    We present new findings on how the presence of particles alters the pinch-off dynamics of a liquid bridge. For moderate concentrations, suspensions initially behave as a viscous liquid with dynamics determined by the bulk viscosity of the suspension. Close to breakup, however, the filament loses its homogeneous shape and localised accelerated breakup is observed. This paper focuses on quantifying these final thinning dynamics for different sized particles with radii between 3 μm and 20 μm in a Newtonian matrix with volume fractions ranging from 0.02 to 0.40. The dynamics of these capillary breakup experiments are very well described by a one-dimensional model that correlates changes in thinning dynamics with the particle distribution in the filament. For all samples, the accelerated dynamics are initiated by increasing particle-density fluctuations that generate locally diluted zones. The onset of these concentration fluctuations is described by a transition radius, which scales with the particle radius and volume fraction. The thinning rate continues to increase and reaches a maximum when the interstitial fluid is thinning between two particle clusters. Contrary to previous experimental studies, we observe that the final thinning dynamics are dominated by a deceleration, where the interstitial fluid appears not to be disturbed by the presence of the particles. By rescaling the experimental filament profiles, it is shown that the pinching dynamics return to the self-similar scaling of a viscous Newtonian liquid bridge in the final moments preceding breakup.

  5. Numerical Study of Pinching Liquid Filament Using VOF Method

    Institute of Scientific and Technical Information of China (English)

    洪若瑜

    2003-01-01

    Study on pinching liquid filament in literature was reviewed. The breakup of liquid filaments under surface tension is governed by incompressible, two-dimensional (2-D), Navier-Stokes Equations. Surface tension was expressed via a CSF (continuous surface force) model that ensures robustness and accuracy. A new surface reconstruction scheme, alternative phase integration (API) scheme was proposed to solve the kinematic equation,and was compared with other three referential schemes. A general-purpose computer program has been developed for simulating transient, 2-D, incompressible fluid flows with free surface of complex topology. The transient behavior of breaking Newtonian liquid filaments under surface tension was simulated successfully using the developed program.The initial wave growth predicted using API-VOF (volume of fluid) scheme was in good agreement with Rayleigh''s linear theory and one-dimensional (l-D) long-wave theory. Both long wave theory and two-dimensional (2-D) API-VOF model on fine meshes show that as time goes on, these waves pinch off large droplets separated by smaller satellite ones that decrease in size with decreasing wavelength. Self-similar structure during the breakup was found using 1-D and 2-D models, and three breakups were predicted for a typical case. The criterion of filament breaking predicted by the 2-D model is that the wavelength is longer than the circumference of a filament. The predicted sizes of main and satellite droplets were compared with published experimental measurements.

  6. Increasing Z-pinch vacuum hohlraum capsule coupling efficiency.

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, Debbie (LLNL); Vesey, Roger Alan; Cochrane, Kyle Robert (KTech); Nikroo, A. (General Atomics); Bennett, Guy R.; Schroen, Diana Grace (Schafer); Ruggles, Laurence E.; Porter, John L.; Streit, Jon (Schafer); Mehlhorn, Thomas Alan; Cuneo, Michael Edward

    2004-11-01

    Symmetric capsule implosions in the double-ended vacuum hohlraum (DEH) on Z have demonstrated convergence ratios of 14-21 for 2.15-mm plastic ablator capsules absorbing 5-7 kJ of x-rays, based on backlit images of the compressed ablator remaining at peak convergence [1]. Experiments with DD-filled 3.3-mm diameter capsules designed to absorb 14 kJ of x-rays have begun as an integrated test of drive temperature and symmetry, complementary to thin-shell symmetry diagnostic capsules. These capsule implosions are characterized by excellent control of symmetry (< 3% time-integrated), but low hohlraum efficiency (< 2%). Possible methods to increase the capsule absorbed energy in the DEH include mixed-component hohlraums, large diameter foam ablator capsules, transmissive shine shields between the z-pinch and capsule, higher spoke electrode x-ray transmission, a double-sided power feed, and smaller initial radius z-pinch wire arrays. Simulations will explore the potential for each of these modifications to increase the capsule coupling efficiency for near-term experiments on Z and ZR.

  7. Increasing Z-pinch vacuum hohlraum capsule coupling efficiency

    International Nuclear Information System (INIS)

    Symmetric capsule implosions in the double-ended vacuum hohlraum (DEH) on Z have demonstrated convergence ratios of 14-21 for 2.15-mm plastic ablator capsules absorbing 5-7 kJ of x-rays, based on backlit images of the compressed ablator remaining at peak convergence (1). Experiments with DD-filled 3.3-mm diameter capsules designed to absorb 14 kJ of x-rays have begun as an integrated test of drive temperature and symmetry, complementary to thin-shell symmetry diagnostic capsules. These capsule implosions are characterized by excellent control of symmetry (< 3% time-integrated), but low hohlraum efficiency (< 2%). Possible methods to increase the capsule absorbed energy in the DEH include mixed-component hohlraums, large diameter foam ablator capsules, transmissive shine shields between the z-pinch and capsule, higher spoke electrode x-ray transmission, a double-sided power feed, and smaller initial radius z-pinch wire arrays. Simulations will explore the potential for each of these modifications to increase the capsule coupling efficiency for near-term experiments on Z and ZR

  8. Process integration and pinch analysis in sugarcane industry

    Energy Technology Data Exchange (ETDEWEB)

    Prado, Adelk de Carvalho; Pinheiro, Ricardo Brant [UFMG, Departamento de Engenharia Nuclear, Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares, Belo Horizonte, MG (Brazil)], E-mail: rbp@nuclear.ufmg.br

    2010-07-01

    Process integration techniques were applied, particularly through the Pinch Analysis method, to sugarcane industry. Research was performed upon harvest data from an agroindustrial complex which processes sugarcane plant in excess of 3.5 million metric tons per year, producing motor fuel grade ethanol, standard quality sugar, and delivering excess electric power to the grid. Pinch Analysis was used in assessing internal heat recovery as well as external utility demand targets, while keeping the lowest but economically achievable targets for entropy increase. Efficiency on the use of energy was evaluated for the plant as it was found (the base case) as well as for five selected process and/or plant design modifications, always with guidance of the method. The first alternative design (case 2) was proposed to evaluate equipment mean idle time in the base case, to support subsequent comparisons. Cases 3 and 4 were used to estimate the upper limits of combined heat and power generation while raw material supply of the base case is kept; both the cases did not prove worth implementing. Cases 5 and 6 were devised to deal with the bottleneck of the plant, namely boiler capacity, in order to allow for some production increment. Inexpensive, minor modifications considered in case 5 were found unable to produce reasonable outcome gain. Nevertheless, proper changes in cane juice evaporation section (case 6) could allow sugar and ethanol combined production to rise up to 9.1% relative to the base case, without dropping cogenerated power. (author)

  9. Necking down of sausages in current-carrying plasma pinches

    International Nuclear Information System (INIS)

    The evolution of long-wave perturbations is shown to be equivalent, for various unstable media, to the dynamics of a gas with a negative adiabatic index γ. This evolution is described (for various values at N) by the quasi-Chaplygin system of equations Several examples of such media are considered, including a ''Chaplygin gas'' (N = 3), drops on a ceiling or ''solitons which have broken'' (N = 0), necks in a current-carrying plasma pinch with a skin effect, for both incompressible and compressible models (N = 2), and the breakup of liquid jets into drops (N = 3/2). A principle for selecting evolutionary solutions corresponding to the absence of perturbations in the limit t → -∞ is formulated. In the cases N = 0 and N = 2, a hodograph transformation reduces system (1) to a magnetostatic equation (ΔA)/sub phi/ = -(4π/c)j/sub phi/ and all the instability modes are equivalent to multipoles of circular currents which are localized on a circle. Exact solutions are given for periodic and isolated (localized) perturbations. The breakup of a medium into distinct blobs, in particular, the rupture of necks in a current-carrying plasma pinch, is demonstrated

  10. Optical diagnostics on dense Z-pinch plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Riley, R.A. Jr.; Lovberg, R.H.; Shlachter, J.S.; Scudder, D.W.

    1992-05-01

    A novel ``point-diffraction`` interferometer has been implemented on the Los Alamos Solid Fiber Z-Pinch experiment. The laser beam is split into two legs after passing through the plasma. The reference leg is filtered with a pin-hole aperture and recombined with the other leg to form an interferogram. This allows compact mounting of the optics and relative ease of alignment. The Z-Pinch experiment employs a pulsed-power generator that delivers up to 700 KA with a 100ns rise-time through a fiber of deuterium or deuterated polyethylene (CD{sub s}) that is 5-cm long and initially solid with radius r{approx}15{mu}m. The interferometer, using a {triangle}t{approx}200ps pulse from a Nd:YAG laser frequency doubled to {lambda}=532nm, measures the electron line density and, assuming azimuthal symmetry, the density as a function of radial and axial position. Calculations predict Faraday rotations of order {pi}/2 for plasma and current densities that this experiment was designed to produce. The resulting periodic loss of fringes would provide the current density distribution.

  11. Study of gas-puff Z-pinches on COBRA

    Energy Technology Data Exchange (ETDEWEB)

    Qi, N.; Rosenberg, E. W.; Gourdain, P. A.; Grouchy, P. W. L. de; Kusse, B. R.; Hammer, D. A.; Bell, K. S.; Shelkovenko, T. A.; Potter, W. M.; Atoyan, L.; Cahill, A. D.; Evans, M.; Greenly, J. B.; Hoyt, C. L.; Pikuz, S. A.; Schrafel, P. C. [Laboratory of Plasma Studies, Cornell University, Ithaca, New York 14853 (United States); Kroupp, E.; Fisher, A.; Maron, Y. [Weizmann Institute of Science, Rehovot 76100 (Israel)

    2014-11-15

    Gas-puff Z-pinch experiments were conducted on the 1 MA, 200 ns pulse duration Cornell Beam Research Accelerator (COBRA) pulsed power generator in order to achieve an understanding of the dynamics and instability development in the imploding and stagnating plasma. The triple-nozzle gas-puff valve, pre-ionizer, and load hardware are described. Specific diagnostics for the gas-puff experiments, including a Planar Laser Induced Fluorescence system for measuring the radial neutral density profiles along with a Laser Shearing Interferometer and Laser Wavefront Analyzer for electron density measurements, are also described. The results of a series of experiments using two annular argon (Ar) and/or neon (Ne) gas shells (puff-on-puff) with or without an on- (or near-) axis wire are presented. For all of these experiments, plenum pressures were adjusted to hold the radial mass density profile as similar as possible. Initial implosion stability studies were performed using various combinations of the heavier (Ar) and lighter (Ne) gasses. Implosions with Ne in the outer shell and Ar in the inner were more stable than the opposite arrangement. Current waveforms can be adjusted on COBRA and it was found that the particular shape of the 200 ns current pulse affected on the duration and diameter of the stagnated pinched column and the x-ray yield.

  12. A reactor study on a belt-shaped screw pinch

    International Nuclear Information System (INIS)

    A previous study on a screw-pinch reactor with circular cross section (ECN-16 (1977) or Rijnhuizen report 77-101) has been extended to a belt configuration which allows to raise β to 0.5. The present study starts from the main assumptions and principal constraints of the previous work, but some technical aspects are treated more realistically. More attention has been paid to the modular construction, the non-uniform distribution of the wall loading, the thermo-hydraulics, the design of and the losses in the coil systems, and the energy storage and electric transmission systems. A potential use of the first wall of the blanket as part of the implosion coil system is suggested. Finally, a conceptual design of a reactor, with a cost estimate is given. Numerical results are given of parameter variations around the values for the reference reactor. The belt screw-pinch reactor with resistive coils turns out to be uneconomical because of its low net efficiency and its high capital costs. The application of superconducting coils to reduce the ohmic losses turns out to be a non-viable alternative. A more promising way to improve the energy balance seems to be the alternative scheme of fuel injection during the burn

  13. Pinch and exergy based thermosolar integration in a dairy process

    International Nuclear Information System (INIS)

    Solar thermal is a promising renewable energy supplying technology that is being introduced slowly in industrial activities. Integration of solar thermal energy in a complex process, in combination with other energy provision devices, must be evaluated carefully, in order to obtain its maximum capacity and performance. This study tackles the integration of the thermosolar technology in a dairy process, sited in a climatic zone where diffuse irradiation is the meaningful one, based on two well developed thermodynamic tools: pinch and exergy analysis. Both tools have been utilized in the context of a low and middle temperature for the production of hot water for the steps of the dairy process. A combined implementation of both methodologies, helped by economical estimation, provides a powerful tool that allows finding the best integration of thermosolar and, by this, taking substantial design decisions. - Highlights: ► Integration of solar thermal energy in an industrial process was assessed. ► Pinch and exergy analysis were used to determine the optimal energy supply configuration. ► Solar thermal energy reduces the fossil energy demand with a moderate investment.

  14. Numerical modeling of an end-plugged theta pinch

    International Nuclear Information System (INIS)

    Analytical and numerical studies of an end-plugged theta pinch are described. The analytical model treats the ablated plug plasma in the quasi-static limit where radiation losses balance energy flowing from the main plasma. This model is used to calculate the enhancement in energy confinement due to an ablating end plug for various plug species. The numerical model employs a one-dimensional, time-dependent magnetohydro-dynamic code. Results of calculations simulating the Scylla IV-P end-plugged theta pinch experiment are presented. The calculations achieve good agreement with the observed decay time of the energy line density. Moreover, the observed tendency toward longer decay times at lower atomic number is also predicted. However, certain notable discrepancies are found. For Si plugs, the calculations indicate a somewhat longer decay time than observed with SiO2 plugs. In addition, an axial compression wave driven by plug ablation causes the calculated energy line density to rise after 15 to 20 μsec which was not observed in the experiments. This is believed to be a feature of the one radial cell model which forbids axial wave dispersion; such dispersion would tend to mute the appearance of such waves. For fusion reactor scale plasma, the calculations predict that higher atomic number leads to negligible enhancements in confinement time

  15. Thermo mechanical analysis and optimization in transient state of the first stage of blades in a gas turbine with internal cooling; Analisis y optimizacion termomecanica, en estado transitorio, de la primera etapa de alabes en una turbina de gas con enfriamiento interno

    Energy Technology Data Exchange (ETDEWEB)

    Campos Amezcua, Alfonso

    2007-04-15

    ). This interface allows integrating the computational models virtually, although they have different grids, and that the CFD model registers the data in center cells, whereas the FEA model registers them in the nodes. Pressure, temperature and velocity profiles were obtained for the fluid and, temperature and stress for the solid. The obtained results are compared with experimental data reported in literature obtaining acceptable results. With this work, information for complementary studies is generated, as failure analysis faults and blade life assessment. [Spanish] Este trabajo presenta una metodologia para el analisis termomecanico de un alabe de turbina de gas con enfriamiento interno, la cual permite eliminar simplificaciones tipicas en este tipo de estudios, tales como: analisis ensamblados de perfiles bidimensionales, que desprecia los efectos tridimensionales del flujo que rodea la punta del alabe entre otras zonas; uso de coeficientes de transferencia de calor semi-empiricos obtenidos de predicciones de flujo adiabatico, entre otros. Esta metodologia utiliza dinamica de fluidos computacional ((CFD) por sus siglas en ingles) para el analisis de flujo y transferencia de calor conjugado y, analisis por elementos finitos ((FEA) por sus siglas en ingles) para el analisis termoestructural, estas tecnicas de simulacion han llegado a ser herramientas estandar para cada uno de los analisis, pero su integracion virtual aun esta en proceso de desarrollo. El codigo de CFD utiliza las ecuaciones de conservacion, asi como ecuaciones constitutivas adicionales para los diversos fenomenos que se presentan, permitiendo utilizar funciones definidas por el usuario para utilizar condiciones de frontera dinamicas en el analisis transitorio y propiedades variables de los materiales, lo cual incrementa la presion de las predicciones. Para resolver las ecuaciones y encontrar una solucion aproximada, se utiliza el metodo de volumen finito. Por otro lado, el codigo de FEA utiliza las

  16. Analisis SWOT Pada Warung Bang Man Di Kawasan Waruug Kopi (Warkop) Harapan Medan

    OpenAIRE

    Ricka Alamia Z

    2008-01-01

    Ricka Alamia Z, 2006. Analisis SWOT Pada Warnng Bang Man di Kawasan Warung Kopi (Warkop) Harapan Medan. Di bawah bimbingan Dra. Marhaini, MS, Ibu Prof. Dr. Ritha F Dalimunthe, SE, MSi (Ketua Departemen Manajemen), ibu Frida Ramadini, SE, MM (Penguji I), Ibu Dra, Lisa Marlina, MSi (Penguji II). Penelitian ini bertujuan untuk menganalisis SWOT yang ada pada Warung Bang Man. Analisis SWOT merupakan penilaian lingkungan internal berupa kekuatan (strength) dan kelemahan (weakness) serta lingkungan...

  17. ANALISIS KOMPARATIF STATIK TERHADAP PERMINTAAN KREDIT PADA BANK SYARIAH DAN BANK KONVENSIONAL DI KOTA MAKASSAR

    OpenAIRE

    Hamzah, Anggriawan Pradana

    2012-01-01

    Permasalahan dalam penelitian ini adalah apakah PDRB, bagi hasil dan laju inflasi berpengaruh terhadap permintaan kredit pada Bank Syariah serta PDRB, suku bunga dan laju inflasi berpengaruh terhadap permintaan kredit pada Bank Konvensional, serta apakah ada perbedaan antara permintaan kredit Bank Syariah dengan Bank Konvensional. Untuk menjawab permasalahan tersebut maka digunakan metode analisis regresi linear sederhana. Hasil analisis yang dilakukan menunjukkan bahwa pengaruh PDRB terha...

  18. Unsur-unsur Humanisme dalam Novel Tabula Rasa Karya Ratih Kumala : Analisis Psikologi Sastra

    OpenAIRE

    Tarigan, Itana

    2011-01-01

    Penelitian ini berjudul Unsur-unsur Humanisme dalam Novel Tabula Rasa Karya Ratih Kumala : Analisis Psikologi Sastra. Penelitian ini bertujuan untuk mengetahui unsur-unsur humanisme. Untuk mencapai tujuan tersebut maka data dikumpulkan dari novel yang berjudul yang berjudul Tabula rasa dengan menggunakan metode membaca heuristik dan hermeneutik. Data yang digunakan yaitu data primer dan data sekunder. Data primer diambil dari bahan analisis yaitu novel Tabula Rasa dan data sekunder diambil ...

  19. Analisis Kualitas Air Dan Hubungannya Dengan Keanekaragaman Vegetasi Akuatik Di Perairan Balige Danau Toba

    OpenAIRE

    Juliana Silalahi

    2010-01-01

    Analisis kualitas air dan hubungannya dengan keanekaragaman vegetasi akuatik telah diteliti pada bulan Agustus 2008 – Maret 2009 pada 4 lokasi penelitian di Perairan Danau Toba, Balige. Lokasi penelitian ditentukan dengan menggunakan metode Purposive Random Sampling berdasarkan aktivitas yang bervariasi pada masing-masing lokasi penelitian, dan setiap stasiun dibagi menjadi 3 titik dengan masing-masing kedalaman yang berbeda yaitu 0m, 5m, 10m, 15m. Analisis dilakukan dengan komputerisasi Prog...

  20. Analisis Kualitas Air dan Hubungannya dengan Keanekaragaman Vegetasi Akuatik di Perairan Parapat Danau Toba

    OpenAIRE

    Eva Fitra

    2009-01-01

    Analisis kualitas air dan hubungannya dengan keanekaragaman vegetasi akuatik telah diteliti pada bulan Januari 2008-April 2008. Metode yang digunakan dalam menentukan lokasi pengambilan sampel adalah “Purpose Random Sampling”. Analisis kualitas air dilihat dari kandungan faktor fisik kimia air yang dianalisis di Puslit SDAL Universitas Sumatera Utara. Identifikasi sampel vegetasi akuatik dilakukan di Laboraturium Ekologi FMIPA Universitas Sumatera Utara Hasil penelitan menunjukkan sifat fi...

  1. Wire-array z pinches as intense x-ray sources for inertial confinement fusion

    International Nuclear Information System (INIS)

    Progress in pulsed power technologies has enabled the use of z pinches for inertial confinement fusion (ICF). Z pinches can provide x-ray powers of 200 TW and x-ray energies approaching 2 MJ. Computational capabilities have advanced to the point that 2-D radiation magneto-hydrodynamics computer codes can be used as detailed design tools. Several ICF configurations have been proposed. The z-pinch driven hohlraum configuration (ZPDH) uses two separate z pinches to provide the radiation to drive an ICF capsule. The decoupling of the z-pinch from the target in the ZPHD permits physics issues such as radiation production, transport, symmetry, and capsule hydrodynamics to be treated separately. The penalty is the increased energy requirement. ZPDH experiments have demonstrated the potential for acceptable capsule symmetry and radiation transport. The dynamic hohlraum concept uses the z pinch itself as a radiation case around the capsule providing the potential for very high coupling efficiency but at the expense of complex z-pinch/target coupling physics. (author)

  2. High yield ICF target design for a Z-pinch driven hohlraum

    International Nuclear Information System (INIS)

    We describe calculations for a high yield inertial fusion design, employing indirect drive with a double-ended z-pinch-driven hohlraum radiation source. A high current (∼60 MA) accelerator implodes z-pinches within an enclosing hohlraum. Radial spoke arrays and shine shields isolate the capsule from the pinch plasma, magnetic field and direct x-ray shine. Our approach places minimal requirements on z-pinch uniformity and stability, usually problematic due to magneto-Rayleigh Taylor (MRT) instability. Large inhomogeneities of the pinch and spoke array may be present, but the hohlraum adequately smooths the radiation field at the capsule. Simultaneity and reproducibility of the pinch x-ray output to better than 7% are required, however, for good symmetry. Recent experiments suggest a pulse shaping technique, through implosion of a multishell z-pinch. X-ray bursts are calculated and observed to occur at each shell collision. A capsule absorbing 1 MJ of x-rays at a peak drive temperature of 210 eV is found to have adequate stability and to produce 400 MJ of yield

  3. Soft x-ray tomography system for the toroidal pinch experiment-RX reversed-field pinch

    Science.gov (United States)

    Koguchi, H.; Shimada, T.; Asai, T.; Yagi, Y.; Hirano, Y.; Sakakita, H.

    2004-10-01

    A soft x-ray (SXR) measurement system for tomography analysis on a reversed-field pinch machine. torodial pinch experiment, RX [TPE-RX, R/a=1.72/0.45 m, Ipsoft x-ray imaging system consists of two surface barrier detector (SBD) arrays that are vertical and horizontal. Thirteen SBDs are installed on the vertical ports and used for the measurement along vertical lines of sight. Eleven SBDs are installed on the horizontal port and used for the measurement along a fan-shaped line of sight. These detectors have 15-μm-thick Be foil with sensitivity in the soft x-ray range. This system is installed in order to study the structure of the SXR emission from the plasma core and to know the relation between global performance and magnetohydrodynamics dynamics. This system has been used under several operating conditions in addition to those of standard operation. The first results of these experiments are reported.

  4. Soft x-ray tomography system for the toroidal pinch experiment-RX reversed-field pinch

    International Nuclear Information System (INIS)

    A soft x-ray (SXR) measurement system for tomography analysis on a reversed-field pinch machine. torodial pinch experiment, RX [TPE-RX, R/a=1.72/0.45 m, Ip<1 MA (designed)], is presented. The soft x-ray imaging system consists of two surface barrier detector (SBD) arrays that are vertical and horizontal. Thirteen SBDs are installed on the vertical ports and used for the measurement along vertical lines of sight. Eleven SBDs are installed on the horizontal port and used for the measurement along a fan-shaped line of sight. These detectors have 15-μm-thick Be foil with sensitivity in the soft x-ray range. This system is installed in order to study the structure of the SXR emission from the plasma core and to know the relation between global performance and magnetohydrodynamics dynamics. This system has been used under several operating conditions in addition to those of standard operation. The first results of these experiments are reported

  5. Uso de la STFT en el análisis de vibraciones para detectar y caracterizar la presencia de un defecto en la superficie de las ruedas de un tren/Use of the STFT in the Vibration Analisys to Detect and Characterice Defects at the Wheels Surface of a Train

    OpenAIRE

    Elkin G. Flórez Serrano.; Foix S. Cardona; Luisa Jordi Nebot

    2012-01-01

    El artículo muestra el procedimiento experimental utilizado para registrar las vibraciones que genera el paso deun tren por un punto fijo del carril. Igualmente muestra la forma de identificar y caracterizar un defecto en la superficie de una rueda, mediante el análisis en el dominio conjunto tiempo-frecuencia de dichas vibraciones utilizando la transformada de Fourier en tiempos cortos -STFT. Los resultados demuestran las ventajas de la STFT en esta aplicación, y cómo el uso de un sistema de...

  6. Analisis termodinamico de los ciclos de rankine

    OpenAIRE

    Fuste Paredes, Sergi

    2015-01-01

    Este proyecto final de grado tiene como objetivo general el estudio y análisis termodinámico del ciclo de Rankine y sus modificaciones. Pretende dar un enfoque general de los distintos parámetros que intervienen y afectan en el aumento del rendimiento de las instalaciones que trabajen con él, así como de las variaciones del ciclo de Rankine para instalaciones de gran potencia, como son el ciclo Rankine con recalentamiento y el ciclo regenerativo de Rankine. En definitiva, la finalidad de este...

  7. NEMÁTODOS PARÁSITOS DE Lutjanus synagris (Linneaus, 1758) Y Lutjanus analis> (Cuvier, 1828) (PERCIFORMES, LUTJANIDAE) EN LAS ZONAS DE SANTA MARTA Y NEGUANJE, CARIBE COLOMBIANO

    OpenAIRE

    Cortés J; Valbuena J.; Manrique G.

    2009-01-01

    Se describen los nemátodos encontrados en el sistema digestivo de las especies de pargo Lutjanus synagris y Lutjanus analis>. Esta investigación se orientó principalmente a la clasificación taxonómica de los parásitos y no a los efectos o patologías que estos puedan ocasionar en los peces. Se tuvo en cuenta que en Colombia los pargos constituyen uno de los recursos de mayor importancia para la comercialización; Lutjanus synagris y

  8. Combined Water-Oxygen Pinch Analysis with Mathematical Programming for Wastewater Treatment

    Institute of Scientific and Technical Information of China (English)

    宋丽丽; 都健; 柴绍斌; 姚平经

    2006-01-01

    Water-oxygen pinch analysis is an effective method to decrease the wastewater quantity and improve the wastewater quality. But when multiple-contaminants are present, the method is difficult to be carried out. In this paper, the method that combines water-oxygen pinch analysis with mathematical programming is proposed. It obtains the general optimal solution and leads to the reuse stream that cannot be found only by pinch analysis. The new method is illustrated by an example, and the annual cost is reduced by 8.43% compared with the solution of literature.

  9. Experimental study of CF4 conical theta pinch plasma expanding into vacuum

    International Nuclear Information System (INIS)

    Langmuir probe, photodiode, and optical multichannel analyzer (OMA) measurements have been made on a pulsed CF4 conical theta pinch plasma. A cloud of CF4 gas was puffed into a conical theta pinch coil, converted to plasma, and propelled into the vacuum region ahead of the expanding gas cloud. At a position 67 cm away from the conical theta pinch coil, the plasma arrived in separate packets that were about 20 μs in duration. The average drift velocity of these packets corresponded to an energy of about 3 eV. The OMA measurements showed that the second packet contained neutral atomic fluorine as well as charged particles

  10. Equilibrium states of Z-pinch with account of radiation and thermal conductivity

    International Nuclear Information System (INIS)

    The problem on equilibrium of cylindrically-symmetric radiative Z-pinch is considered. Radiation energy losses are mainly due to heavy impurity in a deuterium gas. Behaviour dependence of the problem solution on two dimensionless parameters: δ and Pboun, characterizing correspondingly thermal conductivity contribution and plasma pressure on the pinch boundary, is investigated. The equilibrium states obtained are important for definition of initial conditions for numerical simulation of the stage of the second compression of the plasma focus and for investigation of the problem on Z-pinch instability

  11. X-ray imaging measurements of capsule implosions driven by a Z-pinch dynamic hohlraum

    International Nuclear Information System (INIS)

    The radiation and shock generated by impact of an annular tungsten Z-pinch plasma on a 10-mm diam 5-mg/cc CH2 foam are diagnosed with x-ray imaging and power measurements. The radiative shock was virtually unaffected by Z-pinch plasma instabilities. The 5-ns-duration ∼135-eV radiation field imploded a 2.1-mm-diam CH capsule. The measured radiation temperature, shock radius, and capsule radius agreed well with computer simulations, indicating understanding of the main features of a Z-pinch dynamic-hohlraum-driven capsule implosion

  12. The influence of pinching on some technological characteristics of cluster and berry of Italia grape variety

    OpenAIRE

    Dimovska, Violeta; Božinović, Zvonimir; Beleski, Klime; Boskov, Krum

    2007-01-01

    The aim of investigation was to confirm the influence of pinching on some technological characteristics of Italia grape variety: dimension and shape of cluster and berry, mechanical characteristics of berry, and chemical content of must (sugar and total acids). Pinching was applied in two terms (before and after blooming) with two ways: by cutting 1/2 and 1/3 of bunch (P1, P2, P3, P4) and control (K). From the results we can concluded that the time and the way of pinching has the influe...

  13. A review of the dense Z-pinch

    International Nuclear Information System (INIS)

    The Z-pinch, perhaps the oldest subject in plasma physics, has achieved a remarkable renaissance in recent years, following a few decades of neglect due to its basically unstable MHD character. Using wire arrays, a significant transition at high wire number led to a great improvement in both compression and uniformity of the Z-pinch. Resulting from this the Z-accelerator at Sandia at 20 MA in 100 ns has produced a powerful, short pulse, soft x-ray source >230 TW for 4.5 ns) at a high efficiency of ∼15%. This has applications to inertial confinement fusion. Several hohlraum designs have been tested. The vacuum hohlraum has demonstrated the control of symmetry of irradiation on a capsule, while the dynamic hohlraum at a higher radiation temperature of 230 eV has compressed a capsule from 2 mm to 0.8 mm diameter with a neutron yield >3 x 1011 thermal DD neutrons, a record for any capsule implosion. World record ion temperatures of >200 keV have recently been measured in a stainless-steel plasma designed for Kα emission at stagnation, due, it was predicted, to ion-viscous heating associated with the dissipation of fast-growing short wavelength nonlinear MHD instabilities. Direct fusion experiments using deuterium gas-puffs have yielded 3.9 x 1013 neutrons with only 5% asymmetry, suggesting for the first time a mainly thermal source. The physics of wire-array implosions is a dominant theme. It is concerned with the transformation of wires to liquid-vapour expanding cores; then the generation of a surrounding plasma corona which carries most of the current, with inward flowing low magnetic Reynolds number jets correlated with axial instabilities on each wire; later an almost constant velocity, snowplough-like implosion occurs during which gaps appear in the cores, leading to stagnation on the axis, and the production of the main soft-x-ray pulse. These studies have been pursued also with smaller facilities in other laboratories around the world. At Imperial College

  14. Analysis regarding steam generator furnace's incident heat, temperature and composition of combustion gases; Analisis de calor incidente, temperatura y composicion de gases de combustion en hornos de generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Diego Marin, Antonio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    In order to obtain more precise evaluations of the combustion process in the furnace of a steam generator a suction pyrometer has been integrated to measure the temperature of the combustion gases; an ellipsoidal radiometer to measure the incident heat by thermal radiation in the water walls; a water cooled probe to determine the particle concentration, as well as a water cooled probe to determine the composition of the combustion gases present. This document clarifies the form of use of these instruments and their engineering specifications, simultaneously presenting an analysis that considers, unlike others, the internal conditions of the furnace to obtain a more precise evaluation of the efficiency that the combustion process presents and bases for the taking of preventive actions in specific zones of the furnace. Thus, the present work exhibits instruments and techniques of analysis to study the phenomena occurring within a steam generator. [Spanish] Con el fin de obtener evaluaciones mas precisas del proceso de combustion en el horno de un generador de vapor, se ha integrado un pirometro de succion para medir la temperatura de los gases de combustion; un radiometro elipsoidal para medir el calor incidente por radiacion termica en las paredes del agua; una sonda enfriada con agua para determinar la concentracion de particulas, asi como una sonda refrigerada con agua para determinar la composicion de los gases de combustion presentes. Este documento aclara la forma de uso de estos instrumentos y sus especificaciones tecnicas, a la vez que presenta un analisis que considera, a diferencia de otros, las condiciones internas del horno para obtener una evaluacion mas precisa sobre la eficiencia del proceso de combustion y bases para la toma de acciones preventivas en zonas especificas del horno. Asi, el presente trabajo exhibe instrumentos y tecnicas de analisis para estudiar los fenomenos que ocurren dentro de un generador de vapor.

  15. Pinch me - I'm fusing. Fusion Power - what is it? What is a z pinch? And why are z-pinches a promising fusion power technology?

    International Nuclear Information System (INIS)

    The process of combining nuclei (the protons and neutrons inside an atomic nucleus) together with a release of kinetic energy is called fusion. This process powers the Sun, it contributes to the world stockpile of weapons of mass destruction and may one day generate safe, clean electrical power. Understanding the intricacies of fusion power, promised for 50 years, is sometimes difficult because there are a number of ways of doing it. There is hot fusion, cold fusion and con-fusion. Hot fusion is what powers suns through the conversion of mass energy to kinetic energy. Cold fusion generates con-fusion and nobody really knows what it is. Even so, no one is generating electrical power for you and me with either method. In this article the author points out some basic features of the mainstream approaches taken to hot fusion power, as well as describe why z pinches are worth pursuing as a driver for a power reactor and how it may one day generate electrical power for mankind

  16. Pinch me - I'm fusing! Fusion Power - what is it? What is a z pinch? And why are z-pinches a promising fusion power technology?

    Energy Technology Data Exchange (ETDEWEB)

    DERZON,MARK S.

    2000-03-01

    The process of combining nuclei (the protons and neutrons inside an atomic nucleus) together with a release of kinetic energy is called fusion. This process powers the Sun, it contributes to the world stockpile of weapons of mass destruction and may one day generate safe, clean electrical power. Understanding the intricacies of fusion power, promised for 50 years, is sometimes difficult because there are a number of ways of doing it. There is hot fusion, cold fusion and con-fusion. Hot fusion is what powers suns through the conversion of mass energy to kinetic energy. Cold fusion generates con-fusion and nobody really knows what it is. Even so, no one is generating electrical power for you and me with either method. In this article the author points out some basic features of the mainstream approaches taken to hot fusion power, as well as describe why z pinches are worth pursuing as a driver for a power reactor and how it may one day generate electrical power for mankind.

  17. Laser--plasma interaction in a theta-pinch geometry

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, W.T.

    1978-06-01

    Prompt stimulated Brillouin scatter (SBS) is studied in an experiment wherein a high power, pulsed CO/sub 2/ laser irradiates an independently produced, theta-pinch plasma. SBS does not significantly affect laser heating of the plasma. Measurements of density profiles and temperature histories permitted examination of laser refraction, local heating and net absorption. Refractive containment of the CO/sub 2/ laser beam by an on-axis density minimum was observed at early times during the laser pulse. However, refractive containment was lost at late times due to the diffusive loss of the density minimum. Classical modeling of the expected heating required ''bleached'' absorption to account for the observed heating. A plasma absorptivity of approximately 46% was inferred from calorimetry measurements at 250 mtorr fill pressure. These results confirm that classical heating and refraction dominated the laser-plasma interaction.

  18. Pinched flow fractionation devices for detection of single nucleotide polymorphisms

    DEFF Research Database (Denmark)

    Larsen, A.V.; Poulsen, L.; Birgens, H.;

    2008-01-01

    We demonstrate a new and flexible micro fluidic based method for genotyping single nucleotide polymorphisms ( SNPs). The method relies on size separation of selectively hybridized polystyrene microspheres in a micro fluidic pinched flow fractionation (PFF) device. The micro fluidic PFF devices with......, synthesized using human DNA samples from individuals with point mutations in the HBB gene. Following a stringent wash, the beads were separated in a PFF device and the fluorescent signal from the beads was analyzed. Patients being wildtypes, heterozygotes or mutated respectively for the investigated mutation...... could reliably be diagnosed in the PFF device. This indicates that the PFF technique can be used for accurate and fast genotyping of SNPs Udgivelsesdato: 2008...

  19. Measurements of VUV lines on dense Z-pinch plasma

    International Nuclear Information System (INIS)

    The transition n = 1 to n = 2 has the most simple structure of all hydrogen transitions and the corresponding spectralline Ly-α is therefore very appropriate to reveal discrepancies between theory and experiment. In this work mainly the Ly-α spectral line of neutral hydrogen has been studied. The electron density of the Z-pinch amounts to 1.5 x 1024 m-3 with an electron temperature of about 1.2 x 105 K. In this parameter range the plasma can still be studied with spectroscopic methods in the visible spectral region. Based on a space and time resolved measurement of the continuous emission spectra the plasma parameters can be determined independent of line broadening. (orig./HT)

  20. Conceptual Design of a Z-Pinch Fusion Propulsion System

    Science.gov (United States)

    Adams, Robert; Polsgrove, Tara; Fincher, Sharon; Fabinski, Leo; Maples, Charlotte; Miernik, Janie; Stratham, Geoffrey; Cassibry, Jason; Cortez, Ross; Turner, Matthew; Santarius, John; Percy, Thomas

    2010-01-01

    This slide presentation reviews a project that aims to develop a conceptual design for a Z-pinch thruster, that could be applied to develop advanced thruster designs which promise high thrust/high specific impulse propulsion. Overviews shows the concept of the design, which use annular nozzles with deuterium-tritium (D-T) fuel and a Lithium mixture as a cathode, Charts show the engine performance as a function of linear mass, nozzle performance (i.e., plasma segment trajectories), and mission analysis for possible Mars and Jupiter missions using this concept for propulsion. Slides show views of the concepts for the vehicle configuration, thrust coil configuration, the power management system, the structural analysis of the magnetic nozzle, the thermal management system, and the avionics suite,

  1. Laser--plasma interaction in a theta-pinch geometry

    International Nuclear Information System (INIS)

    Prompt stimulated Brillouin scatter (SBS) is studied in an experiment wherein a high power, pulsed CO2 laser irradiates an independently produced, theta-pinch plasma. SBS does not significantly affect laser heating of the plasma. Measurements of density profiles and temperature histories permitted examination of laser refraction, local heating and net absorption. Refractive containment of the CO2 laser beam by an on-axis density minimum was observed at early times during the laser pulse. However, refractive containment was lost at late times due to the diffusive loss of the density minimum. Classical modeling of the expected heating required ''bleached'' absorption to account for the observed heating. A plasma absorptivity of approximately 46% was inferred from calorimetry measurements at 250 mtorr fill pressure. These results confirm that classical heating and refraction dominated the laser-plasma interaction

  2. Physics considerations of the Reversed-Field Pinch fusion reactor

    International Nuclear Information System (INIS)

    A conceptual engineering design of a fusion reactor based on plasma confinement in a toroidal Reversed-Field Pinch (RFP) configuration is described. The plasma is ohmically ignited by toroidal plasma currents which also inherently provide the confining magnetic fields in a toroidal chamber having major and minor radii of 12.7 and 1.5 m, respectively. The DT plasma ignites in 2 to 3 s and undergoes a transient, unrefueled burn at 10 to 20 keV for approx. 20 s to give a DT burnup of approx. 50%. Accounting for all major energy sinks yields a cost-optimized system with a recirculating power fraction of 0.17; the power output is 750 MWe

  3. Advanced-fuel reversed-field pinch reactor (RFPR)

    International Nuclear Information System (INIS)

    The utilization of deuterium-based fuels offers the potential advantages of greater flexibility in blanket design, significantly reduced tritium inventory, potential reduction in radioactivity level, and utilization of an inexhaustible fuel supply. The conventional DT-fueled Reversed-Field Pinch Reactor (RFPR) designs are reviewed, and the recent extension of these devices to advanced-fuel (catalyzed-DD) operation is presented. Attractive and economically competitive DD/RFPR systems are identified having power densities and plasma parameters comparable to the DT systems. Converting an RFP reactor from DT to DD primarily requires increasing the magnetic field levels a factor of two, still requiring only modest magnet coil fields (less than or equal to 4 T). When compared to the mainline tokamak, the unique advantages of the RFP (e.g., high beta, low fields at the coils, high ohmic-heating power densities, unrestricted aspect ratio) are particularly apparent for the utilization of advanced fuels

  4. Catalyzed deuterium fueled reversed-field pinch reactor assessment

    International Nuclear Information System (INIS)

    This study is part of a Department of Energy supported alternate fusion fuels program at Science Applications International Corporation. The purpose of this portion of the study is to perform an assessment of a conceptual compact reversed-field pinch reactor (CRFPR) that is fueled by the catalyzed-deuterium (Cat-d) fuel cycle with respect to physics, technology, safety, and cost. The Cat-d CRFPR is compared to a d-t fueled fusion reactor with respect to several issues in this study. The comparison includes cost, reactor performance, and technology requirements for a Cat-d fueled CRFPR and a comparable cost-optimized d-t fueled conceptual design developed by LANL

  5. Improved confinement of screw pinch plasma in SPICA 2

    International Nuclear Information System (INIS)

    SPICA II is a toroidal screw-pinch device, built to study the confinement and stability properties of plasmas having a highly elongated minor cross-section and a current density profile that is much broader than the pressure profile. This particular configuration is produced by applying a fast-rising toroidal fiels B-T to, and inducing simultaneously a toroidal plasma current I-P-L in, a partially ionized gas. After the shock formation, B-T and I-p-l- are (actively) crowbarred to study the evolution of the plasma. Scince the first report onm SPICA II results the main circuits and the preheating system have been modified in such a way that now each discharge can be routinely passively crowbarred, with a decay time of 0.35 ms, leading to reduced plasma-wall interaction prior to and during the main discharges. (author). 4 refs.; 4 figs

  6. Force-free configurations in reversed-field pinches

    International Nuclear Information System (INIS)

    The structure of reversed-field pinches is analyzed on the basis of analytic solutions of equations describing force-free configurations. A model with a constant coefficient of the proportionality between the current density and the magnetic field is used to analyze the effect of the toroidal geometry on the field distribution and the F--Θ diagrams. A modified model is proposed in which the ratio of the current density to the magnetic field tends toward zero near the wall of the discharge chamber. This model yields a more accurate description of the experiments F--Θ diagrams and of the field distributions. It is preferable to the Bessel-function model from the energy standpoint

  7. Dynamic Variability of Isometric Action Tremor in Precision Pinching

    Directory of Open Access Journals (Sweden)

    Tim Eakin

    2012-01-01

    Full Text Available Evolutionary development of isometric force impulse frequencies, power, and the directional concordance of changes in oscillatory tremor during performance of a two-digit force regulation task was examined. Analyses compared a patient group having tremor confounding volitional force regulation with a control group having no neuropathological diagnosis. Dependent variables for tremor varied temporally and spatially, both within individual trials and across trials, across individuals, across groups, and between digits. Particularly striking findings were magnitude increases during approaches to cue markers and shifts in the concordance phase from pinching toward rigid sway patterns as the magnitude increased. Magnitudes were significantly different among trace line segments of the task and were characterized by differences in relative force required and by the task progress with respect to cue markers for beginning, reversing force change direction, or task termination. The main systematic differences occurred during cue marker approach and were independent of trial sequence order.

  8. Experimental astrophysics with high power lasers and Z pinches

    Energy Technology Data Exchange (ETDEWEB)

    Remington, B A; Drake, R P; Ryutov, D D

    2004-12-10

    With the advent of high energy density (HED) experimental facilities, such as high-energy lasers and fast Z-pinch, pulsed-power facilities, mm-scale quantities of matter can be placed in extreme states of density, temperature, and/or velocity. This has enabled the emergence of a new class of experimental science, HED laboratory astrophysics, wherein the properties of matter and the processes that occur under extreme astrophysical conditions can be examined in the laboratory. Areas particularly suitable to this class of experimental astrophysics include the study of opacities relevant to stellar interiors; equations of state relevant to planetary interiors; strong shock driven nonlinear hydrodynamics and radiative dynamics, relevant to supernova explosions and subsequent evolution; protostellar jets and high Mach-number flows; radiatively driven molecular clouds and nonlinear photoevaporation front dynamics; and photoionized plasmas relevant to accretion disks around compact objects, such as black holes and neutron stars.

  9. Calculating area of fractional-order memristor pinched hysteresis loop

    Directory of Open Access Journals (Sweden)

    Ya-Juan Yu

    2015-11-01

    Full Text Available A fractional-order current-controlled memristor pinched hysteresis loop area is calculated in this study. The area is divided into two parts: one equals to the half of instantaneous power and the other is the part memory of the memristor. Moreover, two parts of the area are affected not only by the cosine components, but also by the sine components. The voltage of the fractional-order current-controlled memristor is no longer an odd function with respect to time and the coefficient of cos(ωt in its Fourier series is zero. In a closed loop, the average power and the memory rely only on sine harmonics of the voltage. Meanwhile, the power and the memory are related to the order of the fractional-order derivative.

  10. Implosion dynamics in double planar wire array Z pinches

    International Nuclear Information System (INIS)

    The double planar wire array (DPWA) Z pinch is a highly efficient radiation source with unique implosion dynamics and precursor formations. The inductively divided current successively ablates the wires and injects the material to the interior of the array. Three uniquely imploding DPWA load types were identified and classified according to the critical load parameter: low, intermediate, or high aspect ratio. Radiation pulse shaping was obtained from secondary precursors: off-axis mass carrying high current densities during the implosion phase. Time-gated EUV spectroscopy of off-axis mass accumulations is used to assess a 60 eV electron temperature prior to the implosion phase. These structures are shown to form by a different mechanism than the secondary precursors. High yields, compact size, and shaped radiation pulses merit further consideration of the DPWA as a candidate for inertial confinement fusion research.

  11. Spectroscopic study of z-pinch stagnation on Z.

    Energy Technology Data Exchange (ETDEWEB)

    Maron, Yitzhak (Weizmann Institute of Science); Weingarten, L. (Weizmann Institute of Science); Starobinets, A. (Weizmann Institute of Science); Fisher, V. (Weizmann Institute of Science); Jennings, Christopher A.; Ampleford, David J.; Bailey, James E.; Yu, Edmund P.; Bernshtam, V. (Weizmann Institute of Science); Cuneo, Michael Edward; Rochau, Gregory Alan; Coverdale, Christine Anne; Jones, Brent Manley; Hansen, Stephanie B.

    2010-11-01

    Fast z-pinches provide intense 1-10 keV photon energy radiation sources. Here, we analyze time-, space-, and spectrally-resolved {approx}2 keV K-shell emissions from Al (5% Mg) wire array implosions on Sandia's Z machine pulsed power driver. The stagnating plasma is modeled as three separate radial zones, and collisional-radiative modeling with radiation transport calculations are used to constrain the temperatures and densities in these regions, accounting for K-shell line opacity and Doppler effects. We discuss plasma conditions and dynamics at the onset of stagnation, and compare inferences from the atomic modeling to three-dimensional magneto-hydrodynamic simulations.

  12. The stability of the high-density z-pinch

    International Nuclear Information System (INIS)

    Fiber-initiated High Density Z-Pinches at Los Alamos, NRL, and Karlsruhe have shown anomalously good stability. Kink modes are never seen, and sausage modes are at least delayed until late in the discharge. The success of these devices in reaching fusion conditions may depend on maintaining and understanding this anomalous stability. We have developed two numerical methods to study the stability in the regime where fluid theory is valid. While our methods are applicable to all modes, we will describe them only for the m=0 sausage mode. The appearance of sausage modes late in the discharge and the total absence of kink modes suggest that an understanding of sausage modes is more urgent, and it is also simpler

  13. The stability of the High-Density Z-Pinch

    International Nuclear Information System (INIS)

    Fiber-initiated High Density Z-Pinches at Los Alamos, NRL, and Karlsruhe have shown anomalously good stability. Kink modes are never seen, and sausage modes are at least delayed until late in the discharge. The success of these devices in reaching fusion conditions may depend on maintaining and understanding this anomalous stability. We have developed two numerical methods to study the stability in the regime where fluid theory is valid. While our methods are applicable to all modes, we will describe them only for the m = 0 sausage mode. The appearance of sausage modes late in the discharge and the total absence of kink modes suggest that an understanding of sausage modes is more urgent, and it is also simpler. 14 refs., 8 figs

  14. Finite wavelength stability of the bumpy theta pinch

    International Nuclear Information System (INIS)

    The stability of the bumpy theta pinch is of importance, not only because of its relevance to the Scyllac experiment but also because in any magnetic confinement scheme the use of (discrete) magnetic coils necessarily introduces bumpiness in the applied field. The long wavelength stability has been considered by Weitzner who performed a double perturbation expansion on the linearized equations of ideal MHD: first in epsilon (characterizing the long wave-length or the modes) then in delta (characterizing the bumpiness of the field lines). The stability of the finite wave-length modes by expanding (only) in the small bumpiness parameter delta is examined. Currents flow only in the ignorable theta direction. (U.K.)

  15. Non linear wave plugging of a theta-pinch plasma

    International Nuclear Information System (INIS)

    A potencial possibility of confining theta-pinch plasma with high power laser beam is examined. The physical process involved is a laser plasma interaction, which can be modeled by non linear cubic polarizability. By means of solutions of wave equations and with the assumption of circular polarization we show that on plasma surface, there are eletromagnetic field gradient forces that can confine plasma, where the peaks of plasma density are in phase with the minimum of electric field (when efects of absorption by collisions are ignored). Also, we present a new formulation to generalize ponderomotive force, where adicional damping mechanism is considered. In this case, peaks of plasma density are in phase with the peaks of electric field. (Author)

  16. Imploding to equilibrium of helically symmetric theta pinches

    International Nuclear Information System (INIS)

    The time-dependent, single-fluid, dissipative magnetohydrodynamic equations are solved in helical coordinates (r,phi), where phi = THETA-kz, k = 2π/L and L is the periodicity length in the z-direction. The two-dimensional numerical calculations simulate theta pinches which have an l = 1 helical field added to them. Given the applied magnetic fields and the initial state of the plasma, we study the time evolution of the system. The plasma is found to experience two kinds of oscillations, occurring on different time scales. These are the radial compression oscillations, and the slower helical oscillations of the plasma column. The plasma motion is followed until these oscillations disappear and an equilibrium is nearly reached. Hence given the amplitude and the rise time of the applied magnetic fields, the calculations allow one to relate the initial state of a cold, homogeneous plasma to its final equilibrium state where it is heated and compressed

  17. Ohmic heating of the reversed-field pinch

    International Nuclear Information System (INIS)

    Simple analytic expressions are found for the global heating rate and the time needed to achieve global power balance with radiation and other losses, in useful agreement with large RFP transport codes. A simple condition is noted, which insures that the heating can be accomplished before appreciable resistive evolution occurs in the pinch profile. The product of poloidal beta, β/sub theta/, and toroidal current, I, that characterizes a condition of global power balance is derived subject to the above-mentioned condition without making key assumptions used by earlier investigators. First, a perfectly steady state (with local power balance) is not assumed, nor is it appropriate to do so. Secondly, the cross-field resistivity is not required to be classical. Since the value of (β/sub theta/ I) plays a fundamental role in determining the kind of device one requires, the foundations of this value are important

  18. Desenvolvimento de metodologia para determinação de 4-cloroanilina em frangos por cromatografia gasosa - espectrometria de massas: análise em tecidos tratados com digluconato de clorhexidina após o processamento térmico Methodology for 4-chloroaniline determination in poultry by GC-MS: analisys in chlorhexidine digluconate treated tissues after termical processing

    Directory of Open Access Journals (Sweden)

    Eduardo Vicente

    2003-12-01

    Full Text Available A degradação do antimicrobiano digluconato de clorhexidina (DGCH durante armazenamento ou processamento térmico pode formar a 4-cloroanilina (CA, um composto potencialmente carcinogênico. Conseqüentemente, o uso deste sanitizante para descontaminação de carcaças de frangos representa uma fonte de risco para o consumidor, devendo ser avaliada a presença da CA no produto tratado. Um método foi desenvolvido para determinação de resíduos de CA em tecidos de frangos. Após a extração com diclorometano, foi feita a limpeza do extrato em cartucho C18 e quantificação por cromatografia gasosa-espectrometria de massas (CG-EM, sem derivação. A recuperação média (89,2% - CV 9,9%. e o limite de detecção (1,8ng/g foram considerados satisfatórios para os propósitos do estudo. Em amostras tratadas com DGCH e não submetidas a processamento térmico, a quantidade de CA detectada foi relativamente baixa, e provavelmente se originou da solução de tratamento. A fritura e a cocção em forno convencional resultaram em níveis elevados de CA, enquanto que a cocção em panela de pressão não alterou os níveis de CA presentes na amostra crua. Em vista destes resultados e, considerando-se o potencial tóxico da CA, recomenda-se que estes dados sejam levados em consideração quando avaliada a utilização de DGCH como sanitizante de carcaças em abatedouros de aves.The degradation of the antimicrobial agent chlorhexidine digluconate (CHDG during storage or thermal process originates 4-chloroaniline (CA, a compound which is potentially carcinogenic. As the use of this sanitizing agent to decontaminate poultry carcasses in processing plants may represent a risk to the consumers, it is important to search for the presence of CA residues in the treated products. A method was developed to quantify CA in poultry tissues. After dichloromethane extraction, the extract was cleaned on a C18 cartridge and the quantitation was performed, without

  19. Magnetoacoustic heating and FCT-equilibria in the belt pinch

    International Nuclear Information System (INIS)

    In the HECTOR belt pinch of high β plasma is produced by magnetic compression in a Tokamak geometry. After compresseion the initial β value can be varied between 0.2 and 0.8. During 5 μs the plasma is further heated by a fast magnetoacoustic wave with a frequency near the first harmonic of the ion cyclotronfrequency. For the first time the β-value of a pinch plasma could be increased further from 0.34 after compression to 0.46 at the end of the rf-heating cycle. By proper selection of the final β-value the region for resonance absorption of the heating wave can be shifted. Strong heating (200 MW) has been observed in the cases, where the resonance region has been located in the center of the plasma. In deuterium discharges an increase in ion temperature is observed during the heating process, whereas the electrons are energetically decoupled, showing no temperature increase. Strong plasma losses are found in the 200 MW range after the rf-heating process. The dominant mechanisms are charge exchange collisions with neutral gas atoms. During rf-heating and the subsequent cooling phase the magnetic flux is frozen due to the high conductivity of the plasma. The observed equilibria could be identified as flux conserving Tokamak (FCT) equilibria. Based on a two-dimensional code the time-evolution of the equilibria has been calculated. The q-profiles are time-independent, with increasing β the magnetic axis of the plasma is shifted towards the outer boundary of the torus, and finally the linear relation between β and βsub(pol), which is characteristic for low-β-equilibria, is no longer valid. Thus for the first time the existence of FCT-equilibria at high β has been demonstrated experimentally together with a qualitative agreement with FCT-theory. (orig./AH)

  20. Instability heating of solid-fiber Z pinches

    International Nuclear Information System (INIS)

    The Los Alamos High Density Z Pinch-II (HDZP-II) facility is used to study the dynamics of z-pinch plasmas generated from solid fibers of deuterated polyethylene CD2 with a range in radii of 3--60 μm. HDZP-II is a pulsed-power generator that delivers a current that rises to 700 kA in 100 ns through an inductive load. A multiframe circular schlieren records the evolution of the shape and size of the plasma on seven images taken at 10-ns intervals. These circular-schlieren images show very strong m=0 instability at the onset of current and a rapid radial expansion of the plasma. No higher-order instabilities are observed. An interferometer is used to infer the electron density and electron line density, giving a measure of the fraction of plasma contained within the outline of the circular-schlieren image at one time during the multiframe sequence. A three-channel x-ray crystal-reflection spectrometer provides the time-resolved, spatially-averaged electron temperature. The magnitude of the x-ray emission at these energies also gives qualitative information about the electron temperature and density at late times. A lower bound on the ion temperature is inferred from the particle pressure needed to balance the magnetic field pressure. The ion temperature rose above that of the electrons, strongly suggesting an additional heating term that puts energy directly into the ions. An ion heating term is proposed to explain the observed rapid radial expansion and elevated ion temperatures. This heating term is based on the assumption that the observed m=0 instabilities reconnect, enclosing magnetic flux which degenerates into turbulence in the plasma. A 0-D simulation is developed to investigate the relevance of different physical models to the data presented

  1. Instability heating of solid-fiber Z pinches

    Energy Technology Data Exchange (ETDEWEB)

    Riley, R.A. Jr.

    1994-02-01

    The Los Alamos High Density Z Pinch-II (HDZP-II) facility is used to study the dynamics of z-pinch plasmas generated from solid fibers of deuterated polyethylene CD{sub 2} with a range in radii of 3--60 {mu}m. HDZP-II is a pulsed-power generator that delivers a current that rises to 700 kA in 100 ns through an inductive load. A multiframe circular schlieren records the evolution of the shape and size of the plasma on seven images taken at 10-ns intervals. These circular-schlieren images show very strong m=0 instability at the onset of current and a rapid radial expansion of the plasma. No higher-order instabilities are observed. An interferometer is used to infer the electron density and electron line density, giving a measure of the fraction of plasma contained within the outline of the circular-schlieren image at one time during the multiframe sequence. A three-channel x-ray crystal-reflection spectrometer provides the time-resolved, spatially-averaged electron temperature. The magnitude of the x-ray emission at these energies also gives qualitative information about the electron temperature and density at late times. A lower bound on the ion temperature is inferred from the particle pressure needed to balance the magnetic field pressure. The ion temperature rose above that of the electrons, strongly suggesting an additional heating term that puts energy directly into the ions. An ion heating term is proposed to explain the observed rapid radial expansion and elevated ion temperatures. This heating term is based on the assumption that the observed m=0 instabilities reconnect, enclosing magnetic flux which degenerates into turbulence in the plasma. A 0-D simulation is developed to investigate the relevance of different physical models to the data presented.

  2. Universality and self-similarity in pinch-off of rods by bulk diffusion

    DEFF Research Database (Denmark)

    Aagesen, Larry K.; Johnson, Anthony E.; Fife, Julie L.;

    2010-01-01

    As rodlike domains pinch off owing to Rayleigh instabilities, a finite-time singularity occurs as the interfacial curvature at the point of pinch-off becomes infinite. The dynamics controlling the interface become independent of initial conditions and, in some cases, the interface attains a...... universal shape1. Such behaviour occurs in the pinching of liquid jets and bridges2, 3, 4, 5, 6, 7, 8, 9 and when pinching occurs by surface diffusion10, 11, 12. Here we examine an unexplored class of topological singularities where interface motion is controlled by the diffusion of mass through a bulk...... liquid rods in an Al–Cu alloy. The universal solution applies to any physical system in which interfacial motion is controlled by bulk diffusion, from the break-up of rodlike reinforcing phases in eutectic composites to topological singularities that occur during coarsening of interconnected bicontinuous...

  3. Pinch-off voltage modeling for CMOS image pixels with a pinned photodiode structure

    International Nuclear Information System (INIS)

    A novel analytical model of pinch-off voltage for CMOS image pixels with a pinned photodiode structure is proposed. The derived model takes account of the gradient doping distributions in the N buried layer due to the impurity compensation formed by manufacturing processes; the impurity distribution characteristics of two boundary PN junctions located in the region for particular spectrum response of a pinned photodiode are quantitative analyzed. By solving Poisson's equation in vertical barrier regions, the relationships between the pinch-off voltage and the corresponding process parameters such as peak doping concentration, N type width and doping concentration gradient of the N buried layer are established. Test results have shown that the derived model features the variations of the pinch-off voltage versus the process implant conditions more accurately than the traditional model. The research conclusions in this paper provide theoretical evidence for evaluating the pinch-off voltage design. (semiconductor devices)

  4. Method for plasma formation for extreme ultraviolet lithography-theta pinch

    Science.gov (United States)

    Hassanein, Ahmed; Konkashbaev, Isak; Rice, Bryan

    2007-02-20

    A device and method for generating extremely short-wave ultraviolet electromagnetic wave, utilizing a theta pinch plasma generator to produce electromagnetic radiation in the range of 10 to 20 nm. The device comprises an axially aligned open-ended pinch chamber defining a plasma zone adapted to contain a plasma generating gas within the plasma zone; a means for generating a magnetic field radially outward of the open-ended pinch chamber to produce a discharge plasma from the plasma generating gas, thereby producing a electromagnetic wave in the extreme ultraviolet range; a collecting means in optical communication with the pinch chamber to collect the electromagnetic radiation; and focusing means in optical communication with the collecting means to concentrate the electromagnetic radiation.

  5. On the stabilization of toroidal pinches by finite larmor radius effects and toroidal magnetic field

    International Nuclear Information System (INIS)

    The radial eigenvalue problem for internal modes in a large aspect ratio toriodal pinch has been solved. A particularly stable regime for a weak but nonzero toroidal magnetic field has been found. (31 refs.)

  6. Theoretical and Numerical Stability Analysis of the Liquid Metal Pinch Using the Shallow Water Approximation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The pinch instability for a cylindrical jet of liquid metal passed through by an axial electrical current is investigated. Besides the pinch effect originating from surface tension, the Lorentz force, created by the axial current density and the corresponding azimuthal magnetic field, causes an electromagnetic pinch effect. This effect has drawn attention in electrical engineering, because it can be used in the construction of liquid metal current limiters with self-healing properties. In this paper a simple model is derived using the shallow water approximation:the equations describing the full system are reduced to two one-dimensional evolution equations for the axial velocity and the radius of the jet. A stability analysis for this reduced system is carried out yielding critical current density and the growth rate for the instability. To investigate the nonlinear behaviour of the pinch instability for finite perturbations simulations, the shallow water model are performed.

  7. Influence of a vacuum region on the stability of a high-beta screw pinch

    International Nuclear Information System (INIS)

    To ascertain the influence of a vacuum region on the stability of a high-β screw pinch, the stability properties of two confinement configurations are compared. Both configurations involve diffuse equilibrium profiles and a rigid, perfectly conducting cylindrical shell. In the first problem, perfectly conducting plasma extends to the rigid conducting wall; the plasma is extremely tenuous in the outer region of the pinch, however. In the second case, profiles identical to those of the first problem are chosen for the central portion of the pinch, but the outer tenuous plasma is replaced by a perfectly insulating vacuum region. The two configruations are found to be unstable for the same range of external parameter values; different modes are unstable in the two cases, however. Thus, the presence of a vacuum region does not affect the stability boundary of the pinch, but it does affect the nature of the unstable modes

  8. Transition from Beam-Target to Thermonuclear Fusion in High-Current Deuterium Z -Pinch Simulations

    Science.gov (United States)

    Offermann, Dustin T.; Welch, Dale R.; Rose, Dave V.; Thoma, Carsten; Clark, Robert E.; Mostrom, Chris B.; Schmidt, Andrea E. W.; Link, Anthony J.

    2016-05-01

    Fusion yields from dense, Z -pinch plasmas are known to scale with the drive current, which is favorable for many potential applications. Decades of experimental studies, however, show an unexplained drop in yield for currents above a few mega-ampere (MA). In this work, simulations of DD Z -Pinch plasmas have been performed in 1D and 2D for a constant pinch time and initial radius using the code Lsp, and observations of a shift in scaling are presented. The results show that yields below 3 MA are enhanced relative to pure thermonuclear scaling by beamlike particles accelerated in the Rayleigh-Taylor induced electric fields, while yields above 3 MA are reduced because of energy lost by the instability and the inability of the beamlike ions to enter the pinch region.

  9. Analisis Faktor-Faktor Yang Mempengaruhi Konsumen Dalam Melakukan Pembelian Kentucky Fried Chicken Pada KFC Jalan Gajah Mada Medan

    OpenAIRE

    Emmelya Kembaren

    2009-01-01

    Tujuan Penelitian ini adalah untuk mengetahui dan menganalisis pengaruh faktor lokasi, produk, harga, merek, program promosi dan pelayanan terhadap keputusan pembelian KFC Gajah Mada Medan, dan faktor yang lebih dominan mempengaruhinya adalah Produk. Penulis menarik hipotesis bahwa faktor lokasi, produk, harga, merek, program promosi dan pelayanan berpengaruh terhadap keputusan pembelian. Metode penelitian yang digunakan adalah metode analisis deskriptif dan metode analisis regresi linier...

  10. ANALISIS KEMAMPUAN BAMBU TALLANG Schyzostachyum branchyladum Kurz. DALAM MENGABSORPSI KARBON DIOKSIDA DI KECAMATAN BUNTAO??? RANTEBUA KABUPATEN TORAJA UTARA

    OpenAIRE

    MAHDALIFAH

    2014-01-01

    Penelitian ???Analisis Kemampuan Bambu Tallang Schizostachyum branchyladum Kurz. Dalam mengabsorpsi Karbon dioksida di Kecamatan Buntao??? Rantebua Kabupaten Toraja Utara???, telah dilakukan pada bulan Nopember 2013 - Januari 2014, yang bertujuan untuk mengetahui kemampuan bambu tallang dalam mengabsorpsi karbon dioksida di Kecamatan Buntao??? Rantebua kabupaten Toraja Utara. Analisis sampel daun dilakukan dengan Metode Nelson Somogy yang menggunakan alat spektrofotometri untuk mengetahui kad...

  11. The effects of shoulder load and pinch force on electromyographic activity and blood flow in the forearm during a pinch task

    DEFF Research Database (Denmark)

    Visser, Bart; Kofoed Nielsen, Pernille; de Kraker, Heleen; Smits, Miriam; Jensen, Bente Rona; Veeger, Dirkjan; van Dieën, Jaap H.

    2006-01-01

    loaded with 4.95 kg each) were combined with intermittent pinch forces at 0, 10 and 25% of the maximum voluntary contraction (MVC). Blood flow to the forearm was measured with Doppler ultrasound. Myoelectric activity of the forearm and neck-shoulder muscles was recorded to check for the workload levels......The object of the current study was to determine whether static contraction of proximal musculature has an effect on the blood flow more distally in the upper extremity. Static contractions of muscles in the neck shoulder region at three levels (relaxed, shoulders elevated and shoulders elevated....... Across all levels of shoulder load, blood flow increased significantly with increasing pinch force (21% at 10% MVC and by 44% at 25% MVC). Blood flow was significantly affected by shoulder load, with the lowest blood flow at the highest shoulder load. Interactions of pinch force and shoulder load were...

  12. Heat Recovery in a Pasta Factory. Pinch Analysis Leads to Optimal Heat Pump Usage.

    OpenAIRE

    Staine, Frédéric; Favrat, Daniel; Krummenacher, Pierre

    1994-01-01

    In the previous issue of the IEA Heat Pump Centre Newsletter (Vol, 12, No.3, pp. 29-31), an article by these authors described the use of pinch analysis (also known as pinch technology) in a buildings application. This article describes a similar procedure for integrating a heat pump into a pasta production process. Many industrial processes, and particularly those dealing with drying, are characterized by an overabundance of low- grade heat which often cannot be effi...

  13. Relationship Between Grip and Pinch Strength and Activities of Daily Living in Stroke Patients

    OpenAIRE

    Bae, Jung Hyun; Kang, Si Hyun; Seo, Kyung Mook; Kim, Don-Kyu; Shin, Hyun Iee; Shin, Hye Eun

    2015-01-01

    Objective To investigate the relationship between grip and pinch strength and independence in activities of daily living (ADL) in stroke patients. Methods Medical records of 577 stroke patients from January 2010 to February 2013 were retrospectively reviewed. Patients' grip and pinch strength of both hemiplegic and non-hemiplegic hands and the Korean version of Modified Barthel Index (K-MBI) score were collected. These patients were divided into three groups: group A (onset duration: ≤3 month...

  14. Nonlinear full two-fluid study of m=0 sausage instabilities in an axisymmetric Z pinch

    International Nuclear Information System (INIS)

    A nonlinear full five-moment two-fluid model is used to study axisymmetric instabilities in a Z pinch. When the electron velocity due to the current J is greater than the ion acoustic speed, high wave-number sausage instabilities develop that initiate shock waves in the ion fluid. This condition corresponds to a pinch radius on the order of a few ion Larmor radii

  15. Auxiliary heating of a theta-pinch plasma by radial magnetoacoustic standing waves

    International Nuclear Information System (INIS)

    Auxiliary heating of a linear theta-pinch plasma column by an externally driven radial magnetoacoustic oscillation has been experimentally investigated. The axial field of the theta pinch was modulated in time at the frequency of the plasma's fundamental radial magnetoacoustic oscillation. The dissipation in the plasma column was sufficient to transfer into the plasma at least 9% of the energy stored in the auxiliary capacitor bank used to drive the oscillation

  16. Current accretion in a ion and cluster emitting pinch with fusion reactions

    International Nuclear Information System (INIS)

    Non random fluctuations in the emission of MeV ions and clusters have been observed in self-field dominated pinches with a non uniform structure on a μ space scale and a high neutron yield/shot, Yn, from D-D fusion reactions. The particle emission increases with Yn in all directions up to Yn ≤Yn , where Y-bar is the mean value of yn from hundreds of shots under identical conditions. The particle emission decreases uniformly for Yn > Y-barn and becomes vanishingly small (except for the charged products of fusion reactions) when Yn approaches the peak yield ≥2 . Y-barn. This is consistent with an enhanced confinement of accelerated D+ ions (during and after the pinch disintegration) within a region of dia. 1-2 cm. The emission of particles is not impaired by the pinch-generated magnetic field if clusters with a charge/mass ratio Z/M ≅ 0 form the bulk of the ejected particle population which may disintegrate on flight. The continuous accretion of current layers (which are trailing the leading current sheath) in the pinch region was stimulated in experiment by inserting suitable field distortion elements in the interelectrode gap. The current distribution in the interelectrode gap was monitored. Current accretion in the pinch region is possible. The bearing of the fusion reaction yield of heavy ions in the pinch on the mechanisms of confinement and of beam-plasma target enhancement is clarified

  17. Self-similar pinch-off mechanism and scaling of ferrofluid drops.

    Science.gov (United States)

    Jiang, Xiao F; Li, Huai Z

    2015-12-01

    The pinch off of heterogeneous ferrofluid drops at a nozzle in air was experimentally investigated with a magnetic field (downward or upward) and without a magnetic field. Compared to homogeneous drops, the self-similarity and universal scaling law were verified through modifying the initial conditions, such as the nozzle diameter, flow rate, and magnitude and direction of the magnetic fields. Two pinch-off points were observed, and the two consecutive pinch-off dynamics were characterized through scaling laws. Here our scaling exponent remains within the scope of (0.70-0.80) for the primary whereas it remains within the scope of (0.60-0.70) for the secondary pinch off, respectively, comparable to the classic range from 2/3 to 1 for homogeneous drops. The gravity-compensating and gravity-superimposing magnetic fields display a negligible effect on the exponent but determine the sequence of double pinch offs. The universal character of the self-similar pinch off is extended to a heterogeneous fluid. PMID:26764624

  18. Space and time resolved observations of plasma dynamics in a compressional gas embedded Z-pinch

    International Nuclear Information System (INIS)

    Recent experiments in a gas embedded compressional Z-pinch are presented. The experiments have been carried out in H2 at 1/3 atm, using a pulse power generator capable of delivering a dl/dt > 1012 A/s. The pinch is initiated by a focused laser pulse, which is coaxial with a cylindrical DC microdischarge. This configuration results in double column pinch at early times, which at current rise evolves into a gas embedded compressional Z-pinch. Diagnostics used are Rogowski coil, single frame holographic interferometry, and holographic shadowgraphy, visible streak camera images from which current, density, line density, pinch radius and plasma motion are obtained. The pinch is characterized by a maximum on axis density which is much higher than the expected value from the filling pressure, with a Bennett temperature of 40 eV at 130 kA. The results shown confirm the high degree of compression achievable with the composite preionization scheme. (author). 4 figs., 5 refs

  19. Application of 2-D simulation to hollow z-pinch implosions

    International Nuclear Information System (INIS)

    The application of simulations of z-pinch implosions should have at least two goals: first, to properly model the most important physical processes occurring in the pinch allowing for a better understanding of the experiments and second, provide a design capability for future experiments. Beginning with experiments fielded at Los Alamos on the Pegasus 1 and Pegasus 2 capacitor banks, the authors have developed a methodology for simulating hollow z-pinches in two dimensions which has reproduced important features of the measured experimental current drive, spectrum, radiation pulse shape, peak power and total radiated energy. This methodology employs essentially one free parameter, the initial level of the random density perturbations imposed at the beginning of the 2-D simulation, but in general no adjustments to other parameters are required. Currently the authors are applying this capability to the analysis of recent Saturn and PBFA-Z experiments. The code results provide insight into the nature of the pinch plasma prior to arrival on-axis, during thermalization and development after peak pinch time. Among other things, the simulation results provide an explanation for the production of larger amounts of radiated energy than would be expected from a simple slug-model kinetic energy analysis and the appearance of multiple peaks in the radiation power. The 2-D modeling has also been applied to the analysis of Saturn dynamic hohlraum experiments and is being used in the design of this and other Z-Pinch applications on PBFA-Z

  20. Study of magnetic fields and current in the Z pinch at stagnation

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, V. V.; Anderson, A. A.; Astanovitskiy, A. L.; Nalajala, V.; Dmitriev, O. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); Papp, D. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); ELI-ALPS, ELI-Hu Nkft., H-6720 Szeged (Hungary)

    2015-09-15

    The structure of magnetic fields in wire-array Z pinches at stagnation was studied using a Faraday rotation diagnostic at the wavelength of 266 nm. The electron plasma density and the Faraday rotation angle in plasma were calculated from images of the three-channel polarimeter. The magnetic field was reconstructed with Abel transform, and the current was estimated using a simple model. Several shots with wire-array Z pinches at 0.5–1.5 MA were analyzed. The strength of the magnetic field measured in plasma of the stagnated pinch was in the range of 1–2 MG. The magnetic field and current profile in plasma near the neck on the pinch were reconstructed, and the size of the current-carrying plasma was estimated. It was found that current flowed in the large-size trailing plasma near the dense neck. Measurements of the magnetic field near the bulge on the pinch also showed current in trailing plasma. A distribution of current in the large-size trailing plasma can prevent the formation of multi-MG fields in the Z pinch.

  1. Self-similar pinch-off mechanism and scaling of ferrofluid drops

    Science.gov (United States)

    Jiang, Xiao F.; Li, Huai Z.

    2015-12-01

    The pinch off of heterogeneous ferrofluid drops at a nozzle in air was experimentally investigated with a magnetic field (downward or upward) and without a magnetic field. Compared to homogeneous drops, the self-similarity and universal scaling law were verified through modifying the initial conditions, such as the nozzle diameter, flow rate, and magnitude and direction of the magnetic fields. Two pinch-off points were observed, and the two consecutive pinch-off dynamics were characterized through scaling laws. Here our scaling exponent remains within the scope of (0.70-0.80) for the primary whereas it remains within the scope of (0.60-0.70) for the secondary pinch off, respectively, comparable to the classic range from 2/3 to 1 for homogeneous drops. The gravity-compensating and gravity-superimposing magnetic fields display a negligible effect on the exponent but determine the sequence of double pinch offs. The universal character of the self-similar pinch off is extended to a heterogeneous fluid.

  2. Scaling the Shear-flow Stabilized Z-pinch to Reactor Conditions

    Science.gov (United States)

    McLean, H. S.; Schmidt, A.; Shumlak, U.; Nelson, B. A.; Golingo, R. P.; Cleveau, E.

    2015-11-01

    We present a conceptual design along with scaling calculations for a pulsed fusion reactor based on the shear-flow-stabilized Z-pinch device. Experiments performed on the ZaP device, at the University of Washington, have demonstrated stable operation for durations of 20 usec at ~100kA discharge current for pinches that are ~1 cm in diameter and 100 cm long. The inverse of the pinch diameter and plasma energy density scale strongly with pinch current and calculations show that maintaining stabilization durations of ~7 usec for increased discharge current (~15x) in a shortened pinch (10 cm) results in a pinch diameter of ~200 um and plasma conditions that approach those needed to support significant fusion burn and energy gain (Ti ~ 30keV, density ~ 3e26/m3, ntau ~1.4e20 sec/m3). Compelling features of the concept include operation at modest discharge current (1.5 MA) and voltage (40kV) along with direct adoption of liquid metals for at least one electrode--technological capabilities that have been proven in existing, commercial, pulse power devices such as large ignitrons. LLNL-ABS-674920. This work performed under the auspices of the U.S. Department of Energy ARPAe ALPHA Program by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  3. Study of magnetic fields and current in the Z pinch at stagnation

    International Nuclear Information System (INIS)

    The structure of magnetic fields in wire-array Z pinches at stagnation was studied using a Faraday rotation diagnostic at the wavelength of 266 nm. The electron plasma density and the Faraday rotation angle in plasma were calculated from images of the three-channel polarimeter. The magnetic field was reconstructed with Abel transform, and the current was estimated using a simple model. Several shots with wire-array Z pinches at 0.5–1.5 MA were analyzed. The strength of the magnetic field measured in plasma of the stagnated pinch was in the range of 1–2 MG. The magnetic field and current profile in plasma near the neck on the pinch were reconstructed, and the size of the current-carrying plasma was estimated. It was found that current flowed in the large-size trailing plasma near the dense neck. Measurements of the magnetic field near the bulge on the pinch also showed current in trailing plasma. A distribution of current in the large-size trailing plasma can prevent the formation of multi-MG fields in the Z pinch

  4. Evolution of plasma flow shear and stability in the ZaP Flow Z-pinch

    International Nuclear Information System (INIS)

    The stabilizing effect of an axial flow on the m=1 kink instability in Z-pinches has been studied numerically with a linearized ideal MHD model to reveal that a sheared axial flow stabilizes the kink mode when the shear exceeds a threshold. The sheared flow stabilizing effect is investigated with the ZaP Flow Z-pinch experiment. An azimuthal array of surface mounted magnetic probes measures the fluctuation levels of the azimuthal modes m=1, 2, and 3. After pinch assembly a quiescent period is found where the mode activity is significantly reduced. The quiescent period lasts for over 2000 times the expected instability growth time in a static Z-pinch. Optical images from a fast framing camera, a two-chord HeNe interferometer, and a ruby holographic interferometer indicate a stable, discrete pinch plasma during this time. Multichord Doppler shift measurements of impurity lines show a large, sheared flow during the quiescent period and low, uniform flow profiles during periods of high mode activity. The value of the velocity shear satisfies the theoretical threshold for stability during the quiescent period and does not satisfy the threshold during the high mode activity. Experiments are conducted with varying amounts of injected neutral gas to gain an understanding of the Z-pinch formation and lifetime. (author)

  5. Evidence of flow stabilization in the ZaP Z pinch experiment

    International Nuclear Information System (INIS)

    The stabilizing effect of an axial flow on the m = 1 kink instability in Z pinches has been studied numerically with a linearized ideal MHD model to reveal that a sheared axial flow stabilizes the kink mode when the shear exceeds a threshold. The sheared flow stabilizing effect is investigated with the flow-through Z pinch experiment, ZaP. An azimuthal array of surface mounted magnetic probes located at the midplane of the 50 cm long pinch plasma measures the fluctuation levels of the azimuthal modes m=1, 2, and 3. After pinch formation a quiescent period is found where the mode activity is reduced to a few percent of the average field. Optical images from a fast framing camera and a HeNe interferometer also indicate a stable pinch plasma during this time. Doppler shift measurements of a C-III line correspond to an axial flow velocity of 9.6x104m/s internal to the pinch. During the time when the axial plasma flow is high, the plasma experiences a quiescent period which lasts approximately 800 exponential growth times predicted by linear theory for a static plasma. (author)

  6. Effects of electron beam pinching on microwave emission in a vircator

    Energy Technology Data Exchange (ETDEWEB)

    Young, D.; Ishihara, O. [Texas Tech Univ., Lubbock, TX (United States); Yatsuzuka, M. [Himeji Inst. of Tech. (Japan)

    1995-12-31

    Electron beam pinching in relativistic diodes has been widely observed. This pinching of electrons is understood to be caused by the flow of ions from the anode together with the flow of electrons from the cathode. The anode flow is created by the heating of the anode by the electron beam. Such a counter flow of electrons and ions is known as a bipolar flow. A vircator experiment at the Himeji Institute of Technology suggested that microwave emission in the vircator was due to a strongly pinched electron beam caused by bipolar flow. A MAGIC particle-in-cell simulation is being developed to study the effects of electron beam pinching on microwave emission in a vircator. Cathode emission from an annular cathode is modeled in the simulation by placing a plasma on the surface of the cathode and an electric field is applied to accelerate the electrons extracted from the plasma. To model the anode emission, the anode is divided into segments. The ion current is then taken to be a fraction of the electron current through each segment. Preliminary results suggest that the pinched electron beam would form a larger virtual cathode potential inside the waveguide behind the diode which should enhance microwave production. The effect of an axially applied magnetic field will also be studied to determine if the magnetic field would suppress electron pinching and microwave emission as was observed in the Himeji experiment.

  7. Exergy analysis in a space with ceiling shield; Analisis exegetico en un espacio con techo escudo

    Energy Technology Data Exchange (ETDEWEB)

    Laboratorio de Energia Solar, Universidad Nacional Autonoma de Mexico (Mexico)

    2009-07-15

    The Solar Laboratory of Energy (LES) of the Universidad Nacional Autonoma de Mexico (UNAM) was designed to be comfortable in spite of the extreme climate where it was built. One of the novel characteristics was the shield type ceiling used in cubicles. In order to compare the effect that had had with respect to the environmental conditions, one had to resort to an exergy analysis, since exergy is a measurement of the capacity of the energy to carry out a work. As a first system the data of the national meteorological system as initial conditions were used. The comparative system used as initial conditions the temperature and relative humidity measurements obtained in 1992 in a cubicle of the LES. Both systems were taken as open. The final conditions were settled at 25 Celsius degrees and 50% of relative humidity in a first case and variables (with respect to the perimeter a comfort zone) in a second case. The saving obtained was of 69% and 33% respectively. Although it is not possible to determine what percentage corresponds to the exclusive saving of the ceiling shield, we see that the cover all altogether, presents a significant exergy saving in respect to modifying the environmental conditions directly. [Spanish] El Laboratorio de Energia Solar (LES) de la Universidad Nacional Autonoma de Mexico (UNAM) fue disenado para ser confortable a pesar del clima extremoso donde fue construido. Una de las caracteristicas novedosas fue el uso de techo tipo escudo en cubiculo. Para comparar el efecto que se tuvo respecto a las condiciones ambientales, se recurrio a un analisis exergetico, ya que la exergia es una medida de la capacidad de la energia para realizar un trabajo. Como un primer sistema se utilizaron los datos del sistema meteorologico nacional como condiciones iniciales. El sistema comparativo utilizo como condiciones iniciales las mediciones de temperatura y humedad relativas obtenidas en 1992 en un cubiculo del LES. Ambos sistemas fueron tomados como abiertos

  8. Hydrodynamic Analysis of the Jaruco-Aguacate Aquifer; Analisis hidrodinamico del acuifero Jaurco-Aguacate

    Energy Technology Data Exchange (ETDEWEB)

    Dilla Salvador, Felix [Centro de Investigaciones Hidraulicas (Cuba)

    2002-03-01

    The paper shows the hydrodynamic analysis of the Jaruco-Aguacate aquifer using an unsteady groundwater flow mathematical model. The simulation includes conditions before and after pumping from a well filed, called El Gato, which is considered, as the most important water source for Havana city. The system is closed to the sea and conformed by an unconfined karstic aquifer with a well defined storage zone; its natural discharge flows through two spring groups. Results obtained with the model for the main spring discharge are near to the measured values, i. e. around 5 m{sup 3}/dec as the mean value for the period without main pumping station. Flow is reduced to 2.5-1.5 m{sup 3}/sec during pumping period but there are no data to confirm this result. Besides, a detailed study of the open boundary of the system is done when piezometric head variation in time is known. The mathematical modelling has been able to simulate the aquifer in its most general conception, in its regional as well as local representation, with a mean deviation of simulated head from observed values less than one meter in both analysed simulated periods. [Spanish] El objetivo del trabajo fue realizar un analisis hidrodinamico del acuifero Jaruco-Aguacate antes y despues de la puesta en marcha del acueducto el Gato, una de las fuentes de abasto mas importantes de la ciudad de La Habana, Cuba, basado en un modelo matematico de simulacion de flujo subterraneo transitorio bidimensional. El acuifero es una llanura carstica cerrada al mar y libre; hacia su centro, la zona de almacenamiento esta bien definida; el sistema de descarga natural realiza por medio de dos grupos de manantiales. El resultado obtenido para el gasto del manantial coincide con los valores aforados para un valor medio de 5 m{sup 3}/seg en el periodo analizado antes del funcionamiento del acueducto, pero su valor se reduce, variando desde 2.5 a 1.5 m{sup 3}/seg, en el periodo posterior, sin embargo, no existe informacion para

  9. Uma abordagem de avaliação de processos baseados no mundo dos custos para processos no mundo dos ganhos em instituições de ensino superior Process analisys for higher education institutions: from the cost world to the throughput world

    Directory of Open Access Journals (Sweden)

    Daniel Pacheco Lacerda

    2009-12-01

    Full Text Available O presente artigo detalha o processo específico de elaboração de preços à luz dos princípios da Contabilidade de Custos para uma organização de ensino superior. O trabalho proPõe uma revisão desse processo, tendo como pano de fundo os conceitos da Teoria das Restrições, no que tange a seu Processo de Raciocínio, e as premissas de custos adotadas na chamada Contabilidade dos Ganhos. Assim, o processo de elaboração do preço é avaliado sistemicamente e um redesenho desse processo alinhado à Contabilidade dos Ganhos é proposto.This paper investigates a University's pricing process, comparing two different accounting approaches: traditional cost accounting and Theory of Constraints. Relying on concepts from the Theory of Constraints, this paper applies the principles of the Thinking Process and Throughput Accounting to review the current approach to this process. As a result, the paper evaluates the dynamics behind such processes and, based on throughput accounting, presents a new approach in tackling this.

  10. Uso de la STFT en el análisis de vibraciones para detectar y caracterizar la presencia de un defecto en la superficie de las ruedas de un tren/Use of the STFT in the Vibration Analisys to Detect and Characterice Defects at the Wheels Surface of a Train

    Directory of Open Access Journals (Sweden)

    Elkin G. Flórez Serrano.

    2012-12-01

    Full Text Available El artículo muestra el procedimiento experimental utilizado para registrar las vibraciones que genera el paso deun tren por un punto fijo del carril. Igualmente muestra la forma de identificar y caracterizar un defecto en la superficie de una rueda, mediante el análisis en el dominio conjunto tiempo-frecuencia de dichas vibraciones utilizando la transformada de Fourier en tiempos cortos -STFT. Los resultados demuestran las ventajas de la STFT en esta aplicación, y cómo el uso de un sistema de monitorizado de las vibraciones generadas en el carril es eficiente y práctico en el mantenimiento predictivo de las ruedas de los trenes.The paper shows the experimental procedure used to record the vibrations generated by the passage of a train in a fixed point of the rail. Moreover, it also shows how to identify and characterize a defect on the surface of a wheel, by analyzing the joined time–frequency domain of these vibrations, using the short time Fourier transform – STFT. The results demonstrate the advantages of the STFTin this application, and that the use of a monitorizazing system of the vibration generated on the railway line is efficient and practical to implement a predictive maintenance of the train wheels.

  11. ANALISIS SPASIAL FAKTOR LINGKUNGAN DAN KEJADIAN DBD DI KABUPATEN DEMAK

    Directory of Open Access Journals (Sweden)

    Musyarifatun Farahiyah

    2014-05-01

    Full Text Available AbstractDengue Haemoragic Fever (DHF was still a public health problem in Demak District, Central Java. In the year of 2012, there were 483 DHF cases and 6 of them were died. Based on those cases, there was no clear information how those cases spread related to environmental and demographic factor. This research aimed to do spatial analysis of DHF incidence then it was related to House Index (HI, Container Index (CI, and the density of houses and occupant. It was an observational research using survey method. This Research took 150 samples of DHF cases. The site of DHF incidence was identified using Geographic Positioning System (GPS device, to gained its coordinat. Environmental and demographic data was collected based on secondary information from District Health Office of Demak. The colected data would be analyzed spatially using ArcView GIS software. This research showed that there was no association between environmental factors (HI, CI with the Incidence Rate (IR of DHF (p-value < 0,05. However, the level of HI and CI was 13,17% and 7,08% respectively. It was a potential condition for DHF spreading in the community. Spatial analysis indicated that Mranggen Sub-district had the most number of DHF incidence that the pattern of spreading covered all area of villages. The higher of population and house density, the higher of Incidence Rate of DHFKeywords : spatial analysis of DHF, environmental factors, DemakAbstrakDemam berdarah dengue (DBD masih merupakan permasalahan serius di Kabupaten Demak Pripinsi Jawa Tengah. Pada tahun 2012, Di Kabupaten Demak terdapat 483 kasus DBD dengan 6 kematian, namun belum diketahui bagaimana sebaran kasus tersebut secara spasial dikaitkan dengan faktor lingkungan dan demografi. Penelitian ini bertujuan untuk melakukan analisis spasial kejadian DBD yang dihubungkan dengan House Index (HI, Container Index (CI, kepadatan penduduk dan kepadatan rumah. Penelitian ini merupakan penelitian observasional dengan metode

  12. ANALISIS RELEVANSI LULUSAN PERGURUAN TINGGI DENGAN DUNIA KERJA

    Directory of Open Access Journals (Sweden)

    Ali Muhson

    2012-04-01

    Full Text Available Abstract: A Relevance Analysis of University Graduates with World of Work. Education should be oriented to the competencies required by the workforce as a percentage of unemployment among the educated increase continuously. This study aims to examine the relevance of YSU Economic Education graduates. The study only focuses on the type of work and subjects taught. The subject of this study is the alumni of Economic Education Study Program. Sampling technique used is snowball sampling. Data collection technique using questionnaires and documentation while the technique of data analysis using descriptive analysis. The result suggests that the majority of the graduates find their first job as private a teacher, a private employee and a tutor, while current job of the most graduates are private teacher, private employee, and civil servant (teacher. The data shows that more than 50 percent of the graduates work in the education area. This implies that the relevance level based on the type of work is categorized as sufficient. Majority of the graduates teaches social science, economic, and entrepreneurship, hence it can be concluded that the relevance level based on the subjects taught is highly relevant.   Keyword: relevance of graduates, type of work, unemployment, employment     Abstrak: Analisis Relevansi Lulusan Perguruan Tinggi dengan Dunia Kerja. Pendidikan harus berorientasi pada kompetensi yang dibutuhkan oleh dunia kerja karena persentase penganggur di kalangan terdidik terus meningkat. Penelitian ini bertujuan untuk mengkaji tingkat relevansi (kesesuaian lulusan Pendidikan Ekonomi UNY. Kajian hanya diarahkan pada jenis pekerjaan dan mata pelajaran yang diampu. Penelitian ini mengambil subjek alumni Prodi Pendidikan Ekonomi dari berbagai angkatan. Teknik sampling yang digunakan adalah snowball sampling. Teknik pengumpulan data menggunakan angket dan dokumentasi sedangkan teknik analisis data menggunakan analisis deskriptif. Penelitian ini

  13. Analysis of the operating cost of Petroleos Mexicanos; Analisis del costo de operacion de petroleos mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Decelis Contreras, Rafael [Petroleos Mexicanos (PEMEX), Mexico (Mexico)

    2006-11-15

    The utility for the operation of Petroleos Mexicanos is the highest world-wide of the oil industry, the official propaganda that we listen every day informs us of a weak company without future, of a company that only associated will be able to come out ahead and this is not so, the present government has received surplus in over excess of the budgeted by more than 500 billion pesos (47,600 million dollars), this money in excess has been thrown to the garbage, because it has not solved any problem for the Mexican nation, in a simple manner, the number of poor people has increased, going from 17.85 million to 19.95, and the total national debt has been increased 42%. We must demand the Secretario de Hacienda Francisco Gil Diaz, to explain to us what has he done with that money. Next, in picture 1 we can appreciate these circumstances in a consistent analysis of 4 years that go from 2002 to 2005. [Spanish] La utilidad de operacion de Petroleos Mexicanos es la mas alta de la industria petrolera mundial, la propaganda oficial que escuchamos todos los dias nos informa de una empresa debil y sin futuro, de una empresa que solamente asociada podra salir adelante y esto no es asi, el gobierno actual a recibido excedentes por encima de lo presupuestado por mas de 500 mil millones de pesos (47,600 millones de dolares), este dinero excedente ha sido tirado a la basura, pues no ha resuelto ningun problema para la nacion mexicana, siendo simplista el numero de pobres ha incrementado, paso de 17.85 millones a 19.95 millones de pobres, y la deuda total nacional se ha incrementado 42%. Tenemos que exigirle al Secretario de Hacienda Francisco Gil Diaz, el tendra que explicarnos que ha hecho con ese dinero, a continuacion en el cuadro 1 podemos apreciar estas circunstancias en un analisis consistente de 4 anos que van de 2002 a 2005.

  14. Development and characterization of a Z-pinch-driven hohlraum high-yield inertial confinement fusion target concept

    International Nuclear Information System (INIS)

    Initial experiments to study the Z-pinch-driven hohlraum high-yield inertial confinement fusion (ICF) concept of Hammer, Tabak, and Porter [Hammer et al., Phys. Plasmas 6, 2129 (1999)] are described. The relationship between measured pinch power, hohlraum temperature, and secondary hohlraum coupling ('hohlraum energetics') is well understood from zero-dimensional semianalytic, and two-dimensional view factor and radiation magnetohydrodynamics models. These experiments have shown the highest x-ray powers coupled to any Z-pinch-driven secondary hohlraum (26±5 TW), indicating the concept could scale to fusion yields of >200 MJ. A novel, single-sided power feed, double-pinch driven secondary that meets the pinch simultaneity requirements for polar radiation symmetry has also been developed. This source will permit investigation of the pinch power balance and hohlraum geometry requirements for ICF relevant secondary radiation symmetry, leading to a capsule implosion capability on the Z accelerator [Spielman et al., Phys. Plasmas 5, 2105 (1998)

  15. Development of a model of synchronous generator with a saturable transformer for the analysis of transient overvoltage in medium voltage systems; Desarrollo de un modelo de generador sincrono con transformador saturable para el analisis de sobrevoltajes transitorios en sistemas de mediana tension

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Martinez, Oscar Alfonso

    2001-02-01

    In this work the problems of the transient overvoltage produced in the components that integrate the synchronous generators installed in industrial systems of medium voltage are approached. The development of a mathematical model in phase components for the synchronous generator is presented. The model includes a current saturation transformer, a system of static excitation and a scheme of grounding by low impedance through an energy cable. In the formulation the effect of the dampening windings is neglected since the interest is only to evaluate the effect of the initial transient overvoltage. Also, symmetry in the phases is considered and the saturation is neglected. The proposed mathematical model was evaluated through cases of simulation using real data of a typical industrial system. Also some tests were conducted in laboratories that, qualitatively, endorse the results obtained by simulation. Two real cases of electrical equipment fault by effect of transient overvoltage in industrial centers in Mexico were analyzed, with generators grounded through high impedance. [Spanish] En este trabajo se aborda la problematica de los sobrevoltajes transitorios producidos en los componentes que integran los generadores sincronos instalados en sistemas industriales de mediana tension. Se presenta el desarrollo de un modelo matematico en componentes de fase para el generador sincrono. El modelo incluye un transformador de corriente saturable, un sistema de excitacion estatica y un esquema de aterrizamiento por baja impedancia a traves de un cable de energia. En la formulacion se desprecia el efecto de los devanados amortiguadores debido a que solo interesa evaluar el efecto del sobrevoltaje transitorio inicial. Asi mismo, se considera simetria en las fases y se desprecia la saturacion. El modelo matematico propuesto fue evaluado a traves de casos de simulacion utilizando datos reales de un sistema industrial tipico. Tambien se realizaron algunas pruebas en laboratorios que

  16. Relationship Between Grip, Pinch Strengths and Anthropometric Variables, Types of Pitch Throwing Among Japanese High School Baseball Pitchers

    OpenAIRE

    Tajika, Tsuyoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shitara, Hitoshi; Ichinose, Tsuyoshi; Shimoyama, Daisuke; Okura, Chisa; Kanazawa, Saeko; Nagai, Ayako; Takagishi, Kenji

    2015-01-01

    Background: Grip and pinch strength are crucially important attributes and standard parameters related to the functional integrity of the hand. It seems significant to investigate normative data for grip and pinch strength of baseball players to evaluate their performance and condition. Nevertheless, few reports have explained the association between grip and pinch strength and anthropometric variables and types of pitch throwing for baseball pitchers. Objectives: The aim of this study was to...

  17. Analisis Komparatif Biaya Hutang Sukuk Dan Obligasi Perusahaan

    Directory of Open Access Journals (Sweden)

    Burhanuddin Jiwandaru

    2014-03-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui perbandingan biaya hutang sukuk dibandingkan dengan obligasi sebagai sumber dana bagi perusahaan. Objek pada penelitian ini adalah seluruh sukuk dan obligasi korporasi yang diterbitkan perusahaan-perusahaan di Indonesia sejak Oktober 2006 sampai Juli 2010. Metode yang dilakukan dalam penelitian ini ialah dengan membandingkan rata-rata biaya hutang sukuk dengan rata-rata biaya hutang obligasi pada perusahaan. Hasil analisis data menunjukan bahwa rata-rata biaya hutang dari seluruh sukuk hampir sama daripada rata-rata biaya hutang dari seluruh obligasi. Bedasarkan data penelitian juga terdapat 21 obligasi yang memiliki biaya hutang yang sama dengan biaya hutang sukuknya, dan hanya terdapat dua obligasi memiliki biaya hutang yang sedikit lebih tinggi dari biaya hutang sukuknya.JEL Classification : G10, G14, G30Keywords : Biaya Hutang, Obligasi, Sukuk

  18. Meta Analisis sa Pagsusuri ng Maiikling Kwento sa mga Tesis at Disertasyon

    Directory of Open Access Journals (Sweden)

    Regina I. Cuizon

    2014-10-01

    Full Text Available Anumang mga pagbabago na makikita sa mundo ay bunga ng pananaliksik. Ang meta-analisis ay isa sa mga bunga ng pananaliksik na ginagamit sa kasalukuyan bilang teknik upang malaman iba pang mga nagsulputang informasyon. Ito’y pag-aaral sa mga pag-aaral. Isang kritikal at sistematikong pagsusuri sa istruktura ng mga pag-aaral. Maging gabay sa mga gradwadong paaralan sa pagpili ng paksang pagaaralan. Pangunahing layunin na matiyak ang mga pamamaraan sa pagsusuri ng maiikling kwento ng mga tesis at disertasyong nagawa mula sa mga piling SUCs. Desinyong kwalitatibo - kontent analisis sa pagsusuri ng: kaanyuan ayon sa suliranin, metodolohiya, paglalahad at interpretasyon ng mga datos, natuklasan, konklusyon, at rekomendasyon; kahinatnan ayon sa pagkatulad, pagkakaiba at kabuluhan; Emerging tema. Napag-alaman na ang karaniwang pinag-aralan ay 30% kahalagahang pangkatauhan, 20% larawangdiwa ng mga kababaihan at 10% gramatikang aspeto. Sa metodolohiyang ginamit, 80% desinyong kwalitatibo at 20% kwantitatibo-kwalitatibo. Sa paglikom ng datos 60% diretsahang pagsusuri, 30% talatanungan at 10% tseklis. Sa pag-analisa 90% kontent analisis at 10% gramatikal analisis. Batay sa natuklasan, ang pagsusuri ng maiikling kwento sa mga tesis at disertasyon mula sa iba’t ibang paaralan gamit ang meta analisis ay isang epektibo, mabisa, objektibong paraan at kagamitan na magagamit sa makatarungang paghatol; pamumuna sa kabuluhan at kagandahan; paghaham- bing sa mga kritikal na isyu; at pormulasyon ng panibagong pamantayan at batas.

  19. Las redes Eurydice y Quipu: potencial para la educación comparada

    Directory of Open Access Journals (Sweden)

    Mercedes Muñoz-Repiso Izaguirre

    1997-01-01

    Full Text Available Como ejemplo significative de las posibles aportaciones que los organismosinternacionales pueden ofrecer a quienes trabajan en Educacion Comparada, este articulo presenta un pormenorizado analisis de las dos redes internacionales de informacioneducativa en las que Espana se encuentra actualmente integrada: Eurydice, de la Union Europea y Quipu, de la Organizacion de Estados Iberoamericanos para la Educacion, la Ciencia y la Cultura. En 61 se hace referencia a los origenes de estas redes, su estructuray sufuncionamiento, y se detallan las actividades mas relevantes que desempefian, planteando, al mismo tiempo, reflexiones sobre sus posibilidades para los comparatistas, para los politicos y administradores de la educacion y para el publico en general, as! como sus aspectos mejorables y propuestas para mejorarlos

  20. ENCAPAI SUMBER DAYA MANUSIA UNGGUL (ANALISIS KINERJA DAN KUALITAS PELAYANAN

    Directory of Open Access Journals (Sweden)

    Ketut Sudarma

    2012-03-01

    Full Text Available Penelitian ini  bertujuan untuk menganalisis pengaruh kemampuan individu, kepuasan kerja, komitmen organisasi terhadap kinerja dan kinerja terhadap kualitas pelayanan. Sampel penelitian berjumlah 76 orang. Teknik pengambilan sampel menggunakan proportional random sampling. Variabel penelitian terdiri dari kemampuan individu, kepuasan kerja, komitmen organisasi, dan kinerja serta kualitas pelayanan  Analisis data menggunakan regresi dua tahap. Hasil penelitian menunjukkan bahwa kemampuan individu, kepuasan kerja dan komitmen organisasi mempunyai pengaruh positif signifikan terhadap kinerja dan kinerja berpengaruh positif signifikan terhadap kualitas pelayanan. Ini berarti semakin meningkat kinerja, maka semakin meningkat juga kualitas pelayanan. Dari hasil analisis deskriptif persentase tampak secara rata-rata  semua variabel penelitian  menunjukkan kategori baik, namun pada aspek-aspek tertentu pada masing-masing variabel masih terdapat kekurangan. Hasil penelitian ini diharapkan dapat menjadi masukan bagi pimpinan dalam meningkatkan kinerja dan kualitas pelayanan. Upaya perbaikan dimulai dari peningkatan kemampuan melalui pendidikan dan latihan, monitoring pelaksanaan kerja secara rutin, menumbuhkan komitmen kerja dan perbaikan standar operasi prosedur.The aim of the study is toanalyze the influence of individual abilities, job satisfaction, organizational commitment to performanceand performance againstservice quality. This samplingmethod is using 76 samples by the proportionalrandom sampling techniques. Variables consisted of individual ability, job satisfaction, organizational commitment, and performance andservice qualitydata analysisusingtwo-stageregression. The results showedthat theability of individuals, job satisfaction and organizational commitment had asignificant positive effecton performance and the performance ofa significant positive effecton quality of service. It means the higher performance, the higher service

  1. ANALISIS KENDALA POTENSIAL PENERAPAN TOTAL QUALITY MANAGEMENT HOTEL PLAZA SEMARANG

    Directory of Open Access Journals (Sweden)

    Hendrajaya -

    2010-03-01

    Full Text Available Penelitian ini bertujuan untuk menemukan faktor-faktor yang terbentuk dari kendala penerapan Total Quality Management (TQM, sebagai upaya untuk menganalisis masalah-masalah potensial dari penerapan TQM di Hotel Plaza, Semarang. Sampel dari penelitian ini sejumlah 65 karyawan Hotel Plaza, Semarang yang terdiri dari manajer dan staf. Teknik analisis menggunakan Faktor Analisis. Hasil penelitian menunjukkan, bahwa kendala potensial dari implementasi TQM dapat disimpulkan menjadi lima faktor, yaitu faktor inkonsistensi, visi-misi, transformasi budaya, manajerial dan manajemen kualitas. Penelitian ini memberikan rekomendasi bahwa peningkatan fungsi-fungsi korporat melalui optimalisasi kualitas sebagai strategi bisnis dan orientasi pada kepuasan konsumen dengan melibatkan seluruh anggota organisasi, akan menjadi dasar untuk memaksimalkan daya saing perusahaan dalam hal produk, layanan, SDM, lingkungan dan seluruh proses yang dapat mendukung upaya perbaikan produktivitas. This study aims to determine the constraint factors and to analyze the potential problems of TQM implementation of Plaza Semarang Hotel. The sample of 65 employees of TQM implementation of Plaza Semarang Hotel, consist of managers and staffs. Factor analysis is used to achieve the results of the potential constraint implementation of Total Quality Management which can be summarized into five factors, they are: the factor of inconsistencies, the factor of vision and mission, cultural transformation factors, managerial factors and the factors of quality management. In order to increase the corporate functions through the optimization of quality as a business strategy and to achieve customer satisfaction, this study suggests that all members of the organization should be involved by the company as on-going basis to maximize the competitiveness of the organization on products, services, human resources, environment and all processes that support productivity improvement.

  2. Computer program for the calculation of stresses in rotary equipment discs; Programas de computo para el calculo de esfuerzos en discos de equipo rotatorio

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez Delgado, Wilson; Kubiak, Janusz; Serrano Romero, Luis Enrique [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    In the preliminary design and diagnosis of rotary machines is very common to utilize simple calculation methods for the mechanical and thermal stresses, dynamic and thermodynamic analysis and flow of fluids in this machines (Gutierrez et al., 1989). The analysis with these methods provides the necessary results for the project initial stage of the machine. Later on, more complex tools are employed to refine the design of some machine components. In the Gutierrez report et al., (1989) 34 programs were developed for the preliminary design and diagnosis of rotating equipment; in this article, one of them is presented in which a method for the analysis of mechanical and thermal stresses is applied in discs of uniform or variable thickness that are normally found in turbomachines and rotary equipment. [Espanol] En el diseno preliminar y diagnostico de maquinas rotatorias es muy comun emplear metodos de calculo sencillos para el analisis de esfuerzos mecanicos y termicos, analisis dinamico y termodinamico y de flujo de fluidos en estas maquinas (Gutierrez et al., 1989). El analisis con estos metodos proporcionan los resultados necesarios para la etapa del proyecto inicial de la maquina. Posteriormente, para refinar el diseno de algunos componentes de la maquina, se aplican las herramientas mas complejas. En el informe de Gutierrez et al., (1989) se desarrollan 34 programas para el diseno preliminar y diagnostico de equipo rotatorio; en este articulo, se presenta uno de ellos, en el que se emplea un metodo para el analisis de esfuerzos mecanicos y termicos en discos de espesor constante o variable que se encuentran comunmente en turbomaquinas y en equipos rotatorios.

  3. Analysis of conjugated heat transfer, in transient state of the first stage of a gas turbine; Analisis de transferencia de calor conjugada, en estado transitorio, de la primera etapa de una turbina de gas

    Energy Technology Data Exchange (ETDEWEB)

    Campos Amezcua, Alfonso; Mazur C, Zdzislaw [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Gallegos Munoz, Armando [Facultad de Ingenieria Mecanica, Electrica y Electronica (FIMEE), Universidad de Guanajuato, Guanajuato (Mexico)

    2007-11-15

    This article presents an analysis of conjugated heat transfer in the first stage of movable blades during the starting of a gas turbine, covering a period of 1,012 seconds. The developed computer model is in 3D and uses as initial and border conditions typical starting curves for stack gases, the cooling air and the angular velocity of the blades. As a result of the numerical predictions, the temperature distributions in stack gases, the trowel of the blade and the cooling air are included, doing emphasis in the results obtained in the solid (body of the blade), since these are used for thermo-mechanical stress analysis and later estimation of the blade residual life. [Spanish] Este articulo presenta un analisis de transferencia de calor conjugada en la primera etapa de alabes moviles, durante el arranque de una turbina de gas, cubriendo un periodo de 1.012 segundos. El modelo computacional desarrollado es en tres dimensiones y utiliza como condiciones iniciales y de frontera curvas de arranque tipicas para los gases de combustion, el aire de enfriamiento y la velocidad angular de los alabes. Como resultado de las predicciones numericas, se incluyen las distribuciones de temperatura en los gases de combustion, la paleta del alabe y el aire de enfriamiento, haciendo enfasis en los resultados obtenidos en el solido (cuerpo del alabe), ya que estos se utilizan para analisis de esfuerzos termomecanicos y posterior estimacion de vida residual del alabe.

  4. Voltage stability analysis considering the load dynamic characteristics and the voltage control devices; Analisis de estabilidad de voltaje considerando las caracteristicas dinamicas de la carga y dispositivos de control de voltaje

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Alvarez, Enrique

    2001-09-15

    improvement of the voltage stability. Finally, the application of the proposed methods of study to the analysis of voltage stability in an electrical network derived from the Mexican Peninsular system is presented. The influence of voltage control devices in the stability phenomenon is discussed and a comparison with the results obtained by means of other analysis techniques are presented, specifically, the study of the Q-V curves and the modal analysis of the power flow equations. [Spanish] El trabajo de investigacion que se presenta en esta tesis se centra en el analisis de la estabilidad de voltaje de mediano plazo considerando el efecto de las caracteristicas de la carga y su interaccion con los modelos de dispositivos de control de voltaje en la red de transmision. Mas concretamente, se define y estudia un tipo de modelo de carga con caracteristicas deseables para el estudio de la estabilidad de voltaje; los modelos genericos de carga derivados de pruebas de campo o de la aplicacion de tecnicas de identificacion y se analiza la influencia de la aplicacion de dispositivos de control para mejorar los margenes de estabilidad del sistema. Se estudian, asimismo, alternativas al modelado de sistemas de potencia para el estudio de la estabilidad de voltaje en sistemas complejos. Se presenta, en primer lugar, un analisis fundamental de las caracteristicas de estabilidad de voltaje en un sistema simplificado de potencia y se introduce el metodo de analisis adoptado. Se muestra que el fenomeno de inestabilidad se manifiesta como una bifurcacion tipo singular inducida del modo critico de voltaje cuando se opera el sistema bajo condiciones de estres. A continuacion, se analiza la contribucion de la accion de dispositivos de control al margen de estabilidad y se deducen criterios de analisis de estabilidad basados en el estudio de dicho modo. Se propone, a continuacion, un modelo lineal del sistema de potencia con caracteristicas deseables para el estudio de la estabilidad de voltaje

  5. Quasi-linear gyrokinetic predictions of the Coriolis momentum pinch in National Spherical Torus Experiment

    Science.gov (United States)

    Guttenfelder, W.; Kaye, S. M.; Ren, Y.; Solomon, W.; Bell, R. E.; Candy, J.; Gerhardt, S. P.; LeBlanc, B. P.; Yuh, H.

    2016-05-01

    This paper presents quasi-linear gyrokinetic predictions of the Coriolis momentum pinch for low aspect-ratio National Spherical Torus Experiment (NSTX) H-modes where previous experimental measurements were focused. Local, linear calculations predict that in the region of interest (just outside the mid-radius) of these relatively high-beta plasmas, profiles are most unstable to microtearing modes that are only effective in transporting electron energy. However, sub-dominant electromagnetic and electrostatic ballooning modes are also unstable, which are effective at transporting energy, particles, and momentum. The quasi-linear prediction of transport from these weaker ballooning modes, assuming they contribute transport in addition to that from microtearing modes in a nonlinear turbulent state, leads to a very small or outward convection of momentum, inconsistent with the experimentally measured inward pinch, and opposite to predictions in conventional aspect ratio tokamaks. Additional predictions of a low beta L-mode plasma, unstable to more traditional electrostatic ion temperature gradient-trapped electron mode instability, show that the Coriolis pinch is inward but remains relatively weak and insensitive to many parameter variations. The weak or outward pinch predicted in NSTX plasmas appears to be at least partially correlated to changes in the parallel mode structure that occur at a finite beta and low aspect ratio, as discussed in previous theories. The only conditions identified where a stronger inward pinch is predicted occur either in the purely electrostatic limit or if the aspect ratio is increased. As the Coriolis pinch cannot explain the measured momentum pinch, additional theoretical momentum transport mechanisms are discussed that may be potentially important.

  6. Quasi-linear gyrokinetic predictions of the Coriolis momentum pinch in National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Guttenfelder, W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; Kaye, S. M. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; Ren, Y. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; Solomon, W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; Bell, R. E. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; Candy, J. [General Atomics, San Diego, California 92186, USA; Gerhardt, S. P. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; LeBlanc, B. P. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA; Yuh, H. [Nova Photonics Inc., Princeton, New Jersey 08540, USA

    2016-05-01

    This paper presents quasi-linear gyrokinetic predictions of the Coriolis momentum pinch for low aspect-ratio National Spherical Torus Experiment (NSTX) H-modes where previous experimental measurements were focused. Local, linear calculations predict that in the region of interest (just outside the mid-radius) of these relatively high-beta plasmas, profiles are most unstable to microtearing modes that are only effective in transporting electron energy. However, sub-dominant electromagnetic and electrostaticballooning modes are also unstable, which are effective at transporting energy, particles, and momentum. The quasi-linear prediction of transport from these weaker ballooning modes, assuming they contribute transport in addition to that from microtearing modes in a nonlinear turbulent state, leads to a very small or outward convection of momentum, inconsistent with the experimentally measured inward pinch, and opposite to predictions in conventional aspect ratio tokamaks. Additional predictions of a low beta L-mode plasma, unstable to more traditional electrostatic ion temperature gradient-trapped electron mode instability, show that the Coriolis pinch is inward but remains relatively weak and insensitive to many parameter variations. The weak or outward pinch predicted in NSTX plasmas appears to be at least partially correlated to changes in the parallel mode structure that occur at a finite beta and low aspect ratio, as discussed in previous theories. The only conditions identified where a stronger inward pinch is predicted occur either in the purely electrostatic limit or if the aspect ratio is increased. As the Coriolis pinch cannot explain the measured momentum pinch, additional theoretical momentum transport mechanisms are discussed that may be potentially important.

  7. The quest for a z-pinch based fusion energy source--a historical perspective

    International Nuclear Information System (INIS)

    Ever since 1958, when Oscar Anderson observed copious neutrons emanating from a 'magnetically self-constricted column of deuterium plasma', scientists have attempted to develop the simple linear pinch into a fusion power source. After all, simple calculations show that if one can pass a current of slightly less than 2 million amperes through a stable D-T plasma, then one could achieve not just thermonuclear break-even, but thermonuclear gain. Moreover, several reactor studies have shown that a simple linear pinch could be the basis for a very attractive fusion system. The problem is, of course, that the seemingly simple act of passing 2 MA through a stable pinch has proven to be quite difficult to accomplish. The pinch tends to disrupt due to instabilities, either by the m=0 (sausage) or m=1 (kink) modes. Curtailing the growth of these instabilities has been the primary thrust of z-pinch fusion research, and over the years a wide variety of formation techniques have been tried. The early pinches were driven by relatively slow capacitive discharges and were formed by imploding a plasma column. The advent of fast pulsed power technology brought on a whole new repertoire of formation techniques, including: fast implosions, laser or field-enhanced breakdown in a uniform volume of gas, a discharge inside a small capillary, a frozen deuterium fiber isolated by vacuum, and staged concepts in which one pinch implodes upon another. And although none of these have yet to be successful, some have come tantalizingly close. This paper will review the history of this four-decade long quest for fusion power

  8. The quest for a z-pinch based fusion energy source emdash a historical perspective

    International Nuclear Information System (INIS)

    Ever since 1958, when Oscar Anderson observed copious neutrons emanating from a open-quotes magnetically self-constricted column of deuterium plasma,close quotes scientists have attempted to develop the simple linear pinch into a fusion power source. After all, simple calculations show that if one can pass a current of slightly less than 2 million amperes through a stable D-T plasma, then one could achieve not just thermonuclear break-even, but thermonuclear gain. Moreover, several reactor studies have shown that a simple linear pinch could be the basis for a very attractive fusion system. The problem is, of course, that the seemingly simple act of passing 2 MA through a stable pinch has proven to be quite difficult to accomplish. The pinch tends to disrupt due to instabilities, either by the m=0 (sausage) or m=1 (kink) modes. Curtailing the growth of these instabilities has been the primary thrust of z-pinch fusion research, and over the years a wide variety of formation techniques have been tried. The early pinches were driven by relatively slow capacitive discharges and were formed by imploding a plasma column. The advent of fast pulsed power technology brought on a whole new repertoire of formation techniques, including: fast implosions, laser or field-enhanced breakdown in a uniform volume of gas, a discharge inside a small capillary, a frozen deuterium fiber isolated by vacuum, and staged concepts in which one pinch implodes upon another. And although none of these have yet to be successful, some have come tantalizingly close. This paper will review the history of this four-decade long quest for fusion power. copyright 1997 American Institute of Physics

  9. Pinch and swell structures: evidence for brittle-viscous behaviour in the middle crust

    Directory of Open Access Journals (Sweden)

    R. Gardner

    2015-04-01

    Full Text Available The flow properties of middle to lower crustal rocks are commonly represented by viscous flow. However, examples of pinch and swell structures found in a mid-crustal high strain zone at St. Anne Point (Fiordland, New Zealand suggest pinch and swell structures are initiated by brittle failure of the more competent layer in conjunction with material softening. On this basis we develop a flexible numerical model using brittle-viscous flow where Mohr–Coulomb failure is utilised to initiate pinch and swell structure development. Results show that pinch and swell structures develop in a competent layer in both Newtonian and non-Newtonian flow provided the competent layer has enough viscosity contrast and initially fails brittlely. The degree of material softening after initial failure is shown to impact pinch and swell characteristics with high rates of material softening causing the formation of thick necks between swells by limiting the successful localisation of strain. The flow regime and yielding characteristics of the matrix do not impact pinch and swell structure formation itself, so long as the matrix is less competent. To aid analysis of the structures and help derive the flow properties of rocks in the field, we define three stages of pinch and swell development and offer suggestions for measurements to be made in the field. Our study suggests that Mohr–Coulomb behaviour combined with viscous flow is an appropriate way to represent the heterogeneous rocks of the middle to lower crust. This type of mid-crustal rheological behaviour has significant influence on the localization of strain at all scales. For example, inclusion of Mohr–Coulomb brittle failure with viscous flow in just some mid-crustal layers within a crustal scale model will result in strain localisation throughout the whole crustal section allowing the development of through-going high strain structures from the upper crust into the middle and lower crust. This

  10. Pinch and swell structures: evidence for brittle-viscous behaviour in the middle crust

    Science.gov (United States)

    Gardner, R.; Piazolo, S.; Daczko, N.

    2015-04-01

    The flow properties of middle to lower crustal rocks are commonly represented by viscous flow. However, examples of pinch and swell structures found in a mid-crustal high strain zone at St. Anne Point (Fiordland, New Zealand) suggest pinch and swell structures are initiated by brittle failure of the more competent layer in conjunction with material softening. On this basis we develop a flexible numerical model using brittle-viscous flow where Mohr-Coulomb failure is utilised to initiate pinch and swell structure development. Results show that pinch and swell structures develop in a competent layer in both Newtonian and non-Newtonian flow provided the competent layer has enough viscosity contrast and initially fails brittlely. The degree of material softening after initial failure is shown to impact pinch and swell characteristics with high rates of material softening causing the formation of thick necks between swells by limiting the successful localisation of strain. The flow regime and yielding characteristics of the matrix do not impact pinch and swell structure formation itself, so long as the matrix is less competent. To aid analysis of the structures and help derive the flow properties of rocks in the field, we define three stages of pinch and swell development and offer suggestions for measurements to be made in the field. Our study suggests that Mohr-Coulomb behaviour combined with viscous flow is an appropriate way to represent the heterogeneous rocks of the middle to lower crust. This type of mid-crustal rheological behaviour has significant influence on the localization of strain at all scales. For example, inclusion of Mohr-Coulomb brittle failure with viscous flow in just some mid-crustal layers within a crustal scale model will result in strain localisation throughout the whole crustal section allowing the development of through-going high strain structures from the upper crust into the middle and lower crust. This localization then has a significant

  11. The physics of the high-density Z-pinch

    International Nuclear Information System (INIS)

    The fiber-initiated High-Density Z-pinch (HDZP) is a novel concept in which fusion plasma could be produced by applying 2 MV along a thin filament of frozen deuterium, 20-30 μm in diameter and 5-10 cm long. The megamp-range currents that result would ohmically heat the fiber to fusion temperatures in 100 ns while maintaining nearly constant radius. The plasma pressure would be held stable by the self-magnetic field for many radial sound transit times during the current-rise phase while, in the case of D-T, a significant fraction of the fiber undergoes thermonuclear fusion. The paper presents results of Los Alamos HDZP studies. Existing experiments and experiments in preparation are described. A succession of theoretical studies, including 1D self-similar and numerical studies of the hot plasma phase. 1D and 2D numerical studies of the cold startup phase, and 3D numerical studies of stability in the hot regime, are presented. (author). 9 refs, 4 figs

  12. Compact Reversed-Field Pinch Reactors (CRFPR): preliminary engineering considerations

    Energy Technology Data Exchange (ETDEWEB)

    Hagenson, R.L.; Krakowski, R.A.; Bathke, C.G.; Miller, R.L.; Embrechts, M.J.; Schnurr, N.M.; Battat, M.E.; LaBauve, R.J.; Davidson, J.W.

    1984-08-01

    The unique confinement physics of the Reversed-Field Pinch (RFP) projects to a compact, high-power-density fusion reactor that promises a significant reduction in the cost of electricity. The compact reactor also promises a factor-of-two reduction in the fraction of total cost devoted to the reactor plant equipment (i.e., fusion power core (FPC) plus support systems). In addition to operational and developmental benefits, these physically smaller systems can operate economically over a range of total power output. After giving an extended background and rationale for the compact fusion approaches, key FPC subsystems for the Compact RFP Reactor (CRFPR) are developed, designed, and integrated for a minimum-cost, 1000-MWe(net) system. Both the problems and promise of the compact, high-power-density fusion reactor are quantitatively evaluated on the basis of this conceptual design. The material presented in this report both forms a framework for a broader, more expanded conceptual design as well as suggests directions and emphases for related research and development.

  13. The Braginskii fluid stability of reversed field pinches

    International Nuclear Information System (INIS)

    Numerical results are presented concerning the linear stability of the current and future generations of RFP's (reversed field pinches). Resistive MHD (magnetohydrodynamics) indicates that finite beta RFP equilibria are unstable to resistive-g modes, and therefore indicates that these may be responsible for confinement degradation. However, as RFP's become more collisionless, terms that are neglected in resistive MHD become significant and should be included in any stability analysis. In this paper, a linear initial value-code has been used to examine the effect of additional terms in the Braginskii equations on the stability of a tearing mode stable equilibrium. In order to make contact with analytical work the additional physics is introduced term by term. The Hall terms alone are shown to stabilise resistive-g modes, but also to destabilise a variant of the ηi-mode. When electron thermal conductivities are also included the ηi-mode remains largely unaffected but the resistive-g mode is no longer stabilised, instead it evolves into a drift-tearing mode that is driven by the electron temperature gradient. Thus in the cold ion limit there are two identifiable branches of instability. The growth-rate of the drift tearing mode is slowed by finite Larmor radius effects, but both it and the ηi-mode remain unstable throughout the collisional ion regime for which the fluid equations are valid. (author)

  14. Murakami density limit in tokamaks and reversed-field pinches

    International Nuclear Information System (INIS)

    A theoretical upper limit for the density in an ohmically heated tokamak discharge follows from the requirement that the ohmic heating power deposited in the central current-carrying channel exceed the impurity radiative cooling in this critical region. A compact summary of our results gives this limit n/sub M/ for the central density as n/sub M/ = [Z/sub e//(Z/sub e/-1]/sup 1/2/n/sub eo/ (B/sub T//1T)(1m/R) where n/sub eo/ depends strongly on the impurity species and is remarkably independent of the central electron temperature T/sub e/(0). For T/sub e/(0) approx. 1 keV, we have n/sub eo/ = 1.5 x 1014 cm-3 for beryllium, n/sub eo/ = 5 x 1013 cm-3 for oxygen, n/sub eo/ = 1.0 x 1013 cm-3 for iron, and n/sub eo/ = 0.5 x 1013 cm-3 for tungsten. The results agree quantitatively with Murakami's original observations. A similar density limit, known as the I/N limit, exists for reversed-field pinch devices and this limit has also been evaluated for a variety of impurity species

  15. Thomson scattering measurements in the RFX reversed field pinch

    International Nuclear Information System (INIS)

    The first systematic measurements of the electron temperature (Te) spatial profile have been obtained in the reversed field pinch experiment RFX with a single pulse Thomson scattering (TS) diagnostic. Scattered light from a ruby laser pulse (E≤15 J, Δt=30 ns) is collected through three objectives from 10 positions along a diameter in the plasma equatorial plane, with a spatial resolution of 2.5 cm. Plasma discharges with current in the range 700 endash 900 kA have been investigated finding evidence of a quite flat Te profile. Data dispersion significantly greater than experimental uncertainties provides an indication of remarkable plasma fluctuations. Results are in good agreement with Te measurements from other single chord spectroscopic diagnostics (SiLi detector and SXR double filter), showing a reliable operation down to an electron density ne=3x1019 m-3. Integration of this apparatus with a ND:YLF laser system for multipulse Thomson scattering measurements, sharing the same input optics, is under way. copyright 1997 American Institute of Physics

  16. Cat-D fueled reversed-field pinch reactor assessment

    International Nuclear Information System (INIS)

    A quantitative comparison of the technology requirements, environmental and cost issues of D-D, Compact Reversed-Field Pinch Reactor (CRFPR) relative to a D-T/CRFPR has been perfomed. The first wall/blanket energy revovery cycle for the D-D reactor is simpler and more efficient than the D-T reactor. In other technology areas (such as magnets and vacuum systems) D-D requirements are not significantly different than the D-T reactor. Tritium technology for processing the plasma exhaust is required to D-D reactors, but no tritium containment around the blanket or heat transport system is needed. Safety analysis shows similar consequences for the release of activated corrosion products or activated first wall/blanket structure. Consequences of all postulated D-D accidents for tritium releases are significantly smaller than those from the D-T reactor. Cost studies have been performed for a series of D-D reactors and compared with the D-T reactor. (orig.)

  17. The interaction of plasma with quartz surfaces in pinch discharges

    International Nuclear Information System (INIS)

    The interaction of plasma with quartz walls was investigated in theta pinch discharges preionized by axial discharges at filling pressures below 12 mTorr. Implantation and sputtering of hydrogen and deuterium in the surface was deduced from neutron yield and Balmer line intensity measurements. A simple model describing these processes yields an implanted deuterium density of 1.6 x 1016/cm2 and a detrapping cross-section of 5 x 10-17 cm2 for a plasma with about 50 eV particle energy. Impurities within the plasma were observed by line intensity measurements. The vacuum and the composition of the filling gas before and after discharges were analysed by means of a mass spectrometer. Stationary conditions could only be obtained after about 30 discharges. The impurity concentration depends on the energy of the preheating discharge, on filling density, on the fact whether the plasma touches the walls during preheating, and on available sources like back diffusion of pump oil, seals, walls and leaks. (Auth.)

  18. Studies of large, non-circular, reversed field pinch discharges

    International Nuclear Information System (INIS)

    Reversed field pinch discharges have been produced in a large (1.39 meter major radius, 0.56 meter average minor radius), thick-walled (5 cm), aluminum vacuum vessel with indented sides. The discharges are self-reversed and ramped up to a current of 300 kA over a time of 10 ms. Reversal is sustained for ≥ 10 resistive diffusion times, despite the presence of large magnetic fluctuations. The influence of the bad poloidal magnetic curvature on RFP stability is examined by measurement of magnetic fluctuations near the plasma edge in the separate bad and good curvature regions of the noncircular plasma for RFP and non-reversed discharges with edge safety factor of 0.4 and 1.4. For q ∼ 1.4 discharges, poloidal field curvature should be small. The large size permits RFP startup at a low toroidal loop voltage (≤ 200 V), which is applied to a gap exposed to plasma, but successfully protected against arcing (up to 300 V). RFP plasmas have also been obtained with toroidal limiters

  19. High yield fusion in a Staged Z-pinch

    CERN Document Server

    Rahman, H U; Rostoker, N; Ney, P

    2008-01-01

    We simulate fusion in a Z-pinch; where the load is a xenon-plasma liner imploding onto a deuterium-tritium plasma target and the driver is a 2 MJ, 17 MA, 95 ns risetime pulser. The implosion system is modeled using the dynamic, 2-1/2 D, radiation-MHD code, MACH2. During implosion a shock forms in the Xe liner, transporting current and energy radially inward. After collision with the DT, a secondary shock forms pre-heating the DT to several hundred eV. Adiabatic compression leads subsequently to a fusion burn, as the target is surrounded by a flux-compressed, intense, azimuthal-magnetic field. The intense-magnetic field confines fusion $\\alpha$-particles, providing an additional source of ion heating that leads to target ignition. The target remains stable up to the time of ignition. Predictions are for a neutron yield of $3.0\\times 10^{19}$ and a thermonuclear energy of 84 MJ, that is, 42 times greater than the initial, capacitor-stored energy.

  20. Paramagnetism and plasma beta in a screw-pinch

    International Nuclear Information System (INIS)

    Anisotropic resistivity causes paramagnetic effects (Bz'(r) less then 0) in a screw pinch, being basically different to the self-relaxation described by Taylor. We compute, analytically and numerically, the resulting effect on equilibrium in a 1-D straight cylindrical plasma. In particular we compute paramagnetic effects on the plasma radius and on plasma beta. Ohm's law also contains diamagnetic terms; in this paper we consider radial particle diffusion and the Nernst effect. In a Tokamak or rector plasma these effects are shown to be negligible, whereas they may contribute in present ULQ, Extrap and RFP experiments. A basic result is an expression for the coupling between the poloidal and axial magnetic field components with the above effects included. A result of specific importance to the Extrap programme is that plasma current limitation can arise from lack of equilibrium when the plasma radius tends to exceed its upper limit, being defined by a magnetic or material limiter. The paramagnetic effect described in this work lowers the plasma beta further, making D-D reactor depending on safety factors q(a) bigger than 1 seems less attainable. (au)

  1. Carbon and oxygen behaviour in the reversed field pinch RFX

    International Nuclear Information System (INIS)

    The emission spectrum measured on the reversed field pinch RFX is dominated by carbon and oxygen lines. Nickel lines are seldom observed even though a large magnetic field perturbation causes intense plasma-wall interaction. The line emissions from hydrogen-like and helium-like ions observed in RFX are simulated by a collisional-radiative impurity diffusion model. An impurity diffusion coefficient of the order of 10 m2/s and an inward convective velocity of 90 m/s have been used for an adequate simulation of the hydrogen-like to helium-like resonant line ratios. The model can be used to estimate the effective charge of the plasma; the on-axis values in 800 kA discharges are found to range between 1.5 and 2.2, with peaks higher than 3 in the presence of carbon blooms. It is found that charge exchange processes with thermal hydrogen neutral atoms must be considered to account for the high G ratio values measured for carbon (0.6 to 0.7). (author). 41 refs, 9 figs, 1 tab

  2. Confined discharge plasma sources for Z-pinch experiments

    International Nuclear Information System (INIS)

    The authors report their investigation Z-pinch implosions on the NRL Gamble II generator using metallic sources of sodium and aluminum, and non-metallic source of sodium (NaF), magnesium (MgF2), and aluminum (Al203). For 1 MA driving currents, peak Κ-shell radiated powers of about 100 GW and energies of about 1.5 kj have been obtained with both pure aluminum and NaF implosions. The aluminum results are comparable to those in previous Gamble II experiments with aluminum wire arrays. Confined discharge sources have been used to generate tens of GW in the Na Heα pump line and flourescence of the neon has been observed. The effects of nozzle shape and size, chamber diameter, amount of fuse material, and confined discharge current have been investigated in Gamble II implosion experiments. These studies indicate that confined discharge sources are capable of supplying significantly more material than required for implosions at the 1 MA level, so that this technique could be extended to higher current generators

  3. Radio frequency wave experiments on the MST reversed field pinch

    International Nuclear Information System (INIS)

    Experiments, simulations, and theory all indicate that the magnetic fluctuations responsible for the poor confinement in the reversed field pinch (RFP) can be controlled by altering the radial profile of the current density. The magnetic fluctuations in the RFP are due to resistive MHD instabilities caused by current profile peaking; thus confinement in the RFP is ultimately the result of a misalignment between inductively driven current profiles and the stable current profiles characteristic of the Taylor state. If a technique such as rf current drive can be developed to non-inductively sustain a Taylor state (a current profile linearly stable to all tearing modes), the confinement of the RFP and its potential as a reactor concept are likely to increase. Whether there is a self-consistent path from poor confinement to greatly improved confinement through current profile modification is an issue for future experiments to address if and only if near term experiments can demonstrate: (1) coupling to and the propagation of rf waves in RFP plasmas, (2) efficient current drive, and (3) control of the power deposition which will make it possible to control the current profile. In this paper, modeling results and experimental plans are presented for two rf experiments which have the potential of satisfying these three goals: high-nparallel lower hybrid (LH) waves and electron Bernstein waves (EBWs)

  4. The physics of the high density Z-pinch

    International Nuclear Information System (INIS)

    The fiber-initiated High-Density Z-Pinch (HDZP) is a novel concept in which fusion plasma could be produced by applying 2 MV along a thin filament of frozen deuterium, 20-30 μm in diameter, 5-10 cm long. The megamp-range currents that result would ohmically heat the fiber to fusion temperatures in 100 ns while maintaining nearly constant radius. The plasma pressure would be held stably by the self-magnetic field for many radial sound transit times during the current-rise phase while, in the case of D-T, a significant fraction of the fiber undergoes thermonuclear fusion. This paper presents results of Los Alamos HDZP studies. Existing and new experiments are described. A succession of theoretical studies, including 1D self-similar and numerical studies of the hot plasma phase, 1D and 2D numerical studies of the cold startup phase, and 3D numerical studies of stability in the hot regime, are then presented. 9 refs., 4 figs

  5. Chaos in reversed-field-pinch plasma simulation and experiment

    International Nuclear Information System (INIS)

    We investigate the possibility that chaos and simple determinism are governing the dynamics of reversed-field-pinch (RFP) plasmas using data from both numerical simulations and experiment. A large repertoire of nonlinear-analysis techniques is used to identify low-dimensional chaos. These tools include phase portraits and Poincare sections, correlation dimension, the spectrum of Lyapunov exponents, and short-term predictability. In addition, nonlinear-noise-reduction techniques are applied to the experimental data in an attempt to extract any underlying deterministic dynamics. Two model systems are used to simulate the plasma dynamics. These are the DEBS computer code, which models global RFP dynamics, and the dissipative trapped-electron-mode model, which models drift-wave turbulence. Data from both simulations show strong indications of low-dimensional chaos and simple determinism. Experimental data were obtained from the Madison Symmetric Torus RFP and consist of a wide array of both global and local diagnostic signals. None of the signals shows any indication of low-dimensional chaos or other simple determinism. Moreover, most of the analysis tools indicate that the experimental system is very high dimensional with properties similar to noise. Nonlinear noise reduction is unsuccessful at extracting an underlying deterministic system

  6. Analytic model for the dynamic Z-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Piriz, A. R., E-mail: roberto.piriz@uclm.es; Sun, Y. B. [E. T. S. I. Industriales, CYTEMA, and Instituto de Investigaciones Energéticas (INEI), Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Tahir, N. A. [GSI Helmholtzzentrum für Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt (Germany)

    2015-06-15

    A model is presented for describing the cylindrical implosion of a shock wave driven by an accelerated piston. It is based in the identification of the acceleration of the shocked mass with the acceleration of the piston. The model yields the separate paths of the piston and the shock. In addition, by considering that the shocked region evolves isentropically, the approximate profiles of all the magnitudes in the shocked region are obtained. The application to the dynamic Z-pinch is presented and the results are compared with the well known snowplow and slug models which are also derived as limiting cases of the present model. The snowplow model is seen to yield a trajectory in between those of the shock and the piston. Instead, the neglect of the inertial effects in the slug model is seen to produce a too fast implosion, and the pressure uniformity is shown to lead to an unphysical instantaneous piston stopping when the shock arrives to the axis.

  7. A hybrid blanket for a reversed-field pinch reactor

    International Nuclear Information System (INIS)

    A hybrid blanket for a reversed-field pinch (RFP) reactor is presented for breeding 233U from thorium. This study focuses on the shellblanket design and assumes a plasma like that used by Culham Laboratory (CL) in its designs. The 233U bred helps the important neutron economy and allows the tritium breeding ratio to be 0.96 at beginning of life for a mean of 1.06 for a 9 MW . yrm2 burnup. A thick conducting shell is assumed for discharge stability and field reversal. This need for a good conductor requires that only pure copper or aluminum or alloys thereof be used. Two designs were investigated, one with a pure copper first wallshell, the other with an aluminum alloy. In these designs 3.4% of the thorium is converted to 233U. In both designs the low metallurgic temperature limit means the large amount of power deposited on and in the shell is not attractive thermodynamically. The resulting large temperature differences in the shell cause high mechanical stresses. The design as it stands is not feasible from the point of view of radiation damage to materials

  8. Spontaneous pinch-off in rotating Hele-Shaw flows

    CERN Document Server

    Folch, R; Ortín, J; Casademunt, J

    2004-01-01

    The dynamics of the interface between two immiscible fluids in a rotating Hele-Shaw cell are studied experimentally, theoretically and by phase-field simulations of the H-S equations. As the central, denser fluid is centrifuged, it forms fingering patterns with long, thin radial filaments ended by a droplet, alternating with incoming fingers of the outer fluid. Simulations show the length (width) of the filaments to grow (decay) roughly exponentially, and the incoming finger tips to asymptotically approach a finite radius for n-fold symmetric initial conditions; these thus tend to a stationary-shape, which is calculated. The filament width decays with a time constant which depends only on the viscosity contrast, whereas its length exhibits a completely universal growth rate, related to the run away of an isolated droplet, for which we give an exact solution. The exponential behavior is clear for high, but not low viscosity contrasts A. Both experiments and simulations show systematic pinch-off of the droplets...

  9. Measuring Fast Ion Losses in a Reversed Field Pinch Plasma

    Science.gov (United States)

    Bonofiglo, P. J.; Anderson, J. K.; Almagri, A. F.; Kim, J.; Clark, J.; Capecchi, W.; Sears, S. H.

    2015-11-01

    The reversed field pinch (RFP) provides a unique environment to study fast ion confinement and transport. The RFP's weak toroidal field, strong magnetic shear, and ability to enter a 3D state provide a wide range of dynamics to study fast ions. Core-localized, 25 keV fast ions are sourced into MST by a tangentially injected hydrogen/deuterium neutral beam. Neutral particle analysis and measured fusion neutron flux indicate enhanced fast ion transport in the plasma core. Past experiments point to a dynamic loss of fast ions associated with the RFP's transition to a 3D state and with beam-driven, bursting magnetic modes. Consequently, fast ion transport and losses in the RFP have garnered recent attention. Valuable information on fast-ion loss, such as energy and pitch distributions, are sought to provide a better understanding of the transport mechanisms at hand. We have constructed and implemented two fast ion loss detectors (FILDs) for use on MST. The FILDs have two, independent, design concepts: collecting particles as a function of v⊥ or with pitch greater than 0.8. In this work, we present our preliminary findings and results from our FILDs on MST. This research is supported by US DOE.

  10. A turbulently heated high-voltage theta pinch

    International Nuclear Information System (INIS)

    The heating of a plasma in a fast theta pinch is described in experiment and numerical simulation. The initial plasma parameters are n0=3x1012-3x1013 cm-3, T00=+-175 G. A shock-like disturbance created by a fast current pulse heats and compresses the plasma. Heating is attributed principally to drift instabilities, namely the Buneman two-stream, the modified two-stream and the ion sound instabilities. Experimental evidence is presented for heating of electrons to approximately 10 keV and ions to temperatures from 3 to tens of keV, depending upon initial conditions. Strongest heating and compression is seen at the lowest densities with antiparallel orientation of bias and pulse magnetic fields. Evidence of turbulent fields is seen, as well as indication of rapid heat loss out the ends of the tube. A numerical model describes the implosion using a two-fluid code with transport modified by local turbulent fields. These are in turn computed from linear and quasi-linear theory. Model and experiment show agreement in overall dynamical behaviour but fail to agree in details of electron and ion heating and sheath thickness. (author)

  11. Superthermal electron diffusion processes in a reversed field pinch

    International Nuclear Information System (INIS)

    In reversed field pinches (RFPs), edge fast electrons play some important roles in the energy transport and RFP dynamo. There have been here detailed measurements of electron currents and floating potential with electrostatic probes at the edge region, showing that field-aligned current is carried by superthermal electrons, which results in reversed toroidal current outside the reversal surface. The time evolution of radial electric field, which is estimated from that of floating potential measured with insertable probes with some assumptions, revealed that radially outward electric field is formed in about 100 μs. Given that the radial electric field is a result of superthermal electron diffusion in a stochastic magnetic field line, then the estimated diffusion coefficient agrees well with the numerically calculated values, which were obtained by using Monte-Carlo particle orbit calculation in combination with a 3-dimensional nonlinear MHD simulation. It is concluded that the radial electric field is formed by stochastic diffusion of superthermal electrons, which also play important roles in RFP dynamo. (author)

  12. Recyclable Transmission Line (RTL) Concept for Z-Pinch IFE*

    Science.gov (United States)

    Olson, C. L.; Slutz, S. A.; Rochau, G. E.; Morrow, C. W.; Kammer, D. C.; Fatenejad, M.; El-Guebaly, L. A.; de Groot, J. S.; Peterson, P. F.

    2003-10-01

    The Recyclable Transmission Line (RTL) concept for IFE uses a recyclable material for the magnetically-insulated transmission line that connects the pulsed power accelerator to the z-pinch fusion target. The RTL may be made of frozen coolant (e.g., Flibe) or a material that is easily separable from the coolant (e.g., low activation ferritic steel). Initial experiments on Saturn at the 10 MA level have already shown excellent electrical turn-on for several candidate RTL materials, and demonstrated high electrical conductivities for thin low-mass RTLs. The present RTL baseline is a 50 kg ferritic steel RTL operating in a 10-20 Torr background chamber pressure. Initial results of investigations are presented on the RTL structural strength (buckling analysis); post-shot RTL formation of schrapnel/plasma; vacuum and electrical RTL connections to the power feed; post-shot effects up the RTL (EMP, schrapnel, etc.); activation and waste stream analysis; study of mechanical properties of foam Flibe; handling of sheer mass of RTLs (one-day storage supply, etc.); and RTL manufacturing and recycling system design.

  13. Compact Reversed-Field Pinch Reactors (CRFPR): preliminary engineering considerations

    International Nuclear Information System (INIS)

    The unique confinement physics of the Reversed-Field Pinch (RFP) projects to a compact, high-power-density fusion reactor that promises a significant reduction in the cost of electricity. The compact reactor also promises a factor-of-two reduction in the fraction of total cost devoted to the reactor plant equipment [i.e., fusion power core (FPC) plus support systems]. In addition to operational and developmental benefits, these physically smaller systems can operate economically over a range of total power output. After giving an extended background and rationale for the compact fusion approaches, key FPC subsystems for the Compact RFP Reactor (CRFPR) are developed, designed, and integrated for a minimum-cost, 1000-MWe(net) system. Both the problems and promise of the compact, high-power-density fusion reactor are quantitatively evaluated on the basis of this conceptual design. The material presented in this report both forms a framework for a broader, more expanded conceptual design as well as suggests directions and emphases for related research and development

  14. Overview of results from the MST reversed field pinch experiment

    International Nuclear Information System (INIS)

    An overview of recent results from the MST programme on physics important for the advancement of the reversed field pinch (RFP) as well as for improved understanding of toroidal magnetic confinement more generally is reported. Evidence for the classical confinement of ions in the RFP is provided by analysis of impurity ions and energetic ions created by 1 MW neutral beam injection (NBI). The first appearance of energetic-particle-driven modes by NBI in a RFP plasma is described. MST plasmas robustly access the quasi-single-helicity state that has commonalities to the stellarator and ‘snake’ formation in tokamaks. In MST the dominant mode grows to 8% of the axisymmetric field strength, while the remaining modes are reduced. Predictive capability for tearing mode behaviour has been improved through nonlinear, 3D, resistive magnetohydrodynamic computation using the measured resistivity profile and Lundquist number, which reproduces the sawtooth cycle dynamics. Experimental evidence and computational analysis indicates two-fluid effects, e.g., Hall physics and gyro-viscosity, are needed to understand the coupling of parallel momentum transport and current profile relaxation. Large Reynolds and Maxwell stresses, plus separately measured kinetic stress, indicate an intricate momentum balance and a possible origin for MST's intrinsic plasma rotation. Gyrokinetic analysis indicates that micro-tearing modes can be unstable at high beta, with a critical gradient for the electron temperature that is larger than for tokamak plasmas by roughly the aspect ratio. (paper)

  15. If it’s pinched it’s a memristor

    Science.gov (United States)

    Chua, Leon

    2014-10-01

    This paper presents an in-depth review of the memristor from a rigorous circuit-theoretic perspective, independent of the material the device is made of. From an experimental perspective, a memristor is best defined as any two-terminal device that exhibits a pinched hysteresis loop in the voltage-current plane when driven by any periodic voltage or current signal that elicits a periodic response of the same frequency. This definition greatly broadens the scope of memristive devices to encompass even non-semiconductor devices, both organic and inorganic, from many unrelated disciplines, including biology, botany, brain science, etc. For pedagogical reasons, the broad terrain of memristors is partitioned into three classes of increasing generality, dubbed Ideal Memristors, Generic Memristors, and Extended Memristors. Each class is distinguished from the others via unique fingerprints and signatures. This paper clarifies many confusing issues, such as non-volatility, dc V-I curves, high-frequency v-i curves, local activity, as well as nonlinear dynamical and bifurcation phenomena that are the hallmarks of memristive devices. Above all, this paper addresses several fundamental issues and questions that many memristor researchers do not comprehend but are afraid to ask.

  16. If it’s pinched it’s a memristor

    International Nuclear Information System (INIS)

    This paper presents an in-depth review of the memristor from a rigorous circuit-theoretic perspective, independent of the material the device is made of. From an experimental perspective, a memristor is best defined as any two-terminal device that exhibits a pinched hysteresis loop in the voltage–current plane when driven by any periodic voltage or current signal that elicits a periodic response of the same frequency. This definition greatly broadens the scope of memristive devices to encompass even non-semiconductor devices, both organic and inorganic, from many unrelated disciplines, including biology, botany, brain science, etc. For pedagogical reasons, the broad terrain of memristors is partitioned into three classes of increasing generality, dubbed Ideal Memristors, Generic Memristors, and Extended Memristors. Each class is distinguished from the others via unique fingerprints and signatures. This paper clarifies many confusing issues, such as non-volatility, dc V–I curves, high-frequency v–i curves, local activity, as well as nonlinear dynamical and bifurcation phenomena that are the hallmarks of memristive devices. Above all, this paper addresses several fundamental issues and questions that many memristor researchers do not comprehend but are afraid to ask. (tutorial)

  17. An investigation of pinch welds using HTS SQUIDs

    International Nuclear Information System (INIS)

    To contain high-pressure gases inside a pressure vessel a seal is often made in a thin-walled tube, known as the stem tube, that connects the gas reservoir and the vessel. This seal can be achieved through the use of a resistance pinch weld that forms with only a limited amount of melting occurring. The lack of melting makes applying traditional post-weld nondestructive evaluation (NDE) techniques extremely difficult. The welds of interest here are made from 304L stainless steel (typically 3.8 mm diameter and 38 mm long) and have a non-uniform geometry that does not inherently lend itself to either eddy current or static field SQUID-based measurement techniques. We perform these NDE measurements with both the sample and the SQUID located inside local electromagnetic shielding. SQUID data are presented as individual time series traces for a set of welds that were fabricated using a broad range of fabrication parameters, and a comparison is made between the SQUID-based results and the known parameters. With the limited spatial resolution offered by our present SQUID system, it is not clear if weld quality can be evaluated from purely SQUID-based results

  18. An investigation of pinch welds using HTS SQUIDs

    Science.gov (United States)

    Carr, Chris; Espy, Michelle A.; Urbaitis, Algis V.; Kraus, Robert H., Jr.

    2006-05-01

    To contain high-pressure gases inside a pressure vessel a seal is often made in a thin-walled tube, known as the stem tube, that connects the gas reservoir and the vessel. This seal can be achieved through the use of a resistance pinch weld that forms with only a limited amount of melting occurring. The lack of melting makes applying traditional post-weld nondestructive evaluation (NDE) techniques extremely difficult. The welds of interest here are made from 304L stainless steel (typically 3.8 mm diameter and 38 mm long) and have a non-uniform geometry that does not inherently lend itself to either eddy current or static field SQUID-based measurement techniques. We perform these NDE measurements with both the sample and the SQUID located inside local electromagnetic shielding. SQUID data are presented as individual time series traces for a set of welds that were fabricated using a broad range of fabrication parameters, and a comparison is made between the SQUID-based results and the known parameters. With the limited spatial resolution offered by our present SQUID system, it is not clear if weld quality can be evaluated from purely SQUID-based results.

  19. Analisis dan Desain BI-Dashboard Monitoring Realisasi Daftar Isian Pelaksanaan Anggaran (DIPA pada Kantor Pelayanan Perbendaharaan Negara (KPPN

    Directory of Open Access Journals (Sweden)

    Ernestina Rahmanasari

    2013-09-01

    Full Text Available Transaksi keuangan badan pemerintahan tingkat daerah dipertanggungjawabkan kepada Kementrian Keuangan melalui Kantor Pelayanan Perbendaharaan Negara (KPPNsetiap bulan dalam bentuk Laporan Keuangan Pemerintah Pusat (LKPP. Laporan Keuangan, didukung dengan teknologi Business Intelligence(BI dashboarddapat dimanfaatkan sebagai data-driven decision support system yang mendorong performa kinerja. Analisis dan desainterhadap pembuatan BI dashboard menunjukkanbagaimana Laporan Keuangan dapat digunakan untuk monitoring realisasi penyerapan dana DIPA dan kinerja instansi secara tepat waktu dan interaktif.Analisis terdiri dari analisis Indikator Kinerja Utama (IKU dan analisis Laporan Keuangan. IKUpada analisis dan desain ini mencakup ketercapaian estimasi dengan penerimaan, ketercapaian pagu dengan belanja, ketepatan waktu pengiriman rekonsiliasi oleh instansi, validasi, akurasi, dan ketepatan data. Desain terdiri dari katalog dashboard, alur analisis, sumber data, desain User-Interface, dan desain objek dashboard. Sedangkan dashboard yang dirancang menggunakan aplikasi Vera sebagai Enterprise System, mengakses basis data MySQL, dan menampilkan data dengan teknologi data-driven business-intelligence Qlikview. Desain aplikasi yang telah dibuat akan menampilkan 4 (empat Tab yaitu: Dashboard utama, Analisis, Monitoring, dan Laporan

  20. A new graphical method for Pinch Analysis applications: Heat exchanger network retrofit and energy integration

    International Nuclear Information System (INIS)

    Energy integration is a key solution in chemical process and crude refining industries to minimise external fuel consumption and to face the impact of growing energy crises. Typical energy integration projects can reach a reduction of heating fuels and cold utilities by up to 40% compared with original designs or existing installations. Pinch Analysis is a leading tool and regarded as an efficient method to increase energy efficiency and minimise fuel flow consumptions. It is valid for both natures of design, grassroots and retrofit situations. It can practically be applied to synthesise a HEN (heat exchanger network) or modify an existing preheat train for minimum energy consumption. Heat recovery systems or HENs are networks for exchanging heat between hot and cold process sources. All heat transferred from hot process sources into cold process sinks represent the scope for energy integration. On the other hand, energies required beyond this integrated amount are to be satisfied by external utilities. Graphical representations of Pinch Analysis, such as Composite and Grand Composite Curves are very useful for grassroots designs. Nevertheless, in retrofit situation the analysis is not adequate and besides it is graphically tedious to represent existing exchangers on such graphs. This research proposes a new graphical method for the analysis of heat recovery systems, applicable to HEN retrofit. The new graphical method is based on plotting temperatures of process hot streams versus temperatures of process cold streams. A new graph is constructed for representing existing HENs. For a given network, each existing exchanger is represented by a straight line, whose slope is proportional to the ratio of heat capacities and flows. Further, the length of each exchanger line is related to the heat flow transferred across this exchanger. This new graphical representation can easily identify exchangers across the pinch, Network Pinch, pinching matches and improper placement

  1. ANALISIS STEGANOGRAFI METODE LEAST SIGNIFICANT BIT (LSB DENGAN PENYISIPAN SEKUENSIAL DAN ACAK SECARA KUANTITATIF DAN VISUAL

    Directory of Open Access Journals (Sweden)

    Erwin Yudi Hidayat

    2013-08-01

    Full Text Available Penelitian ini bertujuan untuk melakukan analisis terhadap steganografi Least Significant Bit (LSB yang mampu menyisipkan pesan secara sekuensial dan acak. Analisis dilakukan untuk mengetahui penyisipan yang manakah yang memiliki kemampuan paling baik. Secara kuantitatif, Peak Signal to Noise Ratio (PSNR digunakan untuk mengukur kualitas citra. Sedangkan secara visual, steganalisis Enhanced LSB dimanfaatkan untuk mengetahui teknik mana yang mampu menyisipkan pesan tanpa mudah dideteksi. Hasil percobaan menunjukkan, penyisipan secara acak memiliki kemampuan lebih baik daripada penyisipan secara sekuensial. Kata Kunci: steganografi, acak, sekuensial, PSNR, Enhanced LSB

  2. Narrazioni ed analisi qualitativa: una lettura di alcune biografie di criminali

    Directory of Open Access Journals (Sweden)

    Loredana Teresa Pedata

    2010-06-01

    Full Text Available L'articolo presenta una ricerca di tipo qualitativo condotta con il software Atlas.ti: si tratta di un software per l'analisi qualitativa molto flessibile che permette di lavorare con materiale diverso; proprio queste caratteristiche lo rendono utilizzabile in diversi ambiti e settori.Il materiale scelto per l'indagine è costituito da alcune biografie di criminali. La ricerca vuole dunque effettuare un'analisi sulle narrazioni. La narrazione costituisce, infatti, una modalità per organizzare gli episodi sociali, le azioni e i loro resoconti.In questa sede verranno riportati e discussi i primi risultati della ricerca.

  3. A novel graphical technique for Pinch Analysis applications: Energy Targets and grassroots design

    International Nuclear Information System (INIS)

    Graphical abstract: A new HEN graphical design. - Highlights: • A new graphical technique for heat exchanger networks design. • Pinch Analysis principles and design rules are better interpreted. • Graphical guidelines for optimum heat integration. • New temperature-based graphs provide user-interactive features. - Abstract: Pinch Analysis is for decades a leading tool to energy integration for retrofit and design. This paper presents a new graphical technique, based on Pinch Analysis, for the grassroots design of heat exchanger networks. In the new graph, the temperatures of hot streams are plotted versus those of the cold streams. The temperature–temperature based graph is constructed to include temperatures of hot and cold streams as straight lines, horizontal lines for hot streams, and vertical lines for cold streams. The graph is applied to determine the pinch temperatures and Energy Targets. It is then used to synthesise graphically a complete exchanger network, achieving the Energy Targets. Within the new graph, exchangers are represented by inclined straight lines, whose slopes are proportional to the ratio of heat capacities and flows. Pinch Analysis principles for design are easily interpreted using this new graphical technique to design a complete exchanger network. Network designs achieved by the new technique can guarantee maximum heat recovery. The new technique can also be employed to simulate basic designs of heat exchanger networks. The strengths of the new tool are that it is simply applied using computers, requires no commercial software, and can be used for academic purposes/engineering education

  4. X-ray Thomson Scattering using the Hybrid X-pinch X-ray Source

    Science.gov (United States)

    Hoyt, Cad; Pikuz, Sergei; Shelkovenko, Tania; Hammer, Dave

    2013-10-01

    Stringent photometric and bandwidth requirements have historically relegated X-ray Thomson scattering (XRTS) probe sources to high energy laser plasma sources or free electron lasers. Standard x-pinch configurations in which two or more fine wires cross and subtend an angle of about 30° forming an ``X'' between the anode and cathode of a pulsed power generatorcan produce extremely bright, subnanosecond bursts of continuum and line radiation from micron-scale sources. The hybrid x-pinch is a new configuration based on conical W-Cu alloy electrodes with a short 1-2 mm gap that is bridged by a fine wire resulting in an easier to load setup with improved performance characteristics. We explore the possibility of utilizing the hybid x-pinch as a novel XRTS probe source by examining certain spectral and temporal attributes of a range of materials in a hybrid x-pinch configuration on the XP (500 kA, 50 ns) and COBRA(1MA, 100ns) pulsed power generators. We find that a Ti hybrid x-pinch produces >1012 photons/sr in Ti He-alpha radiation and satisfies the noncollective scattering bandwidth requirement. Measurements of photon fluence, bandwidth and applicability to the relevant scattering regime and initial scattering results will be presented.

  5. Application of Proton Deflectometry to Z-Pinch Plasma Systems at the Mega-Ampere Scale

    Science.gov (United States)

    Mariscal, Derek; McGuffey, Chris; Valenzuela, Julio; Wei, Mingsheng; Beg, Farhat; Presura, Radu; Haque, Showera; Arias, Angel; Covington, Aaron; Sawada, Hiroshi; Chittenden, Jeremy

    2013-10-01

    Measuring magnetic fields in z-pinch plasmas is challenging. Typical laser-probing diagnostics are limited by the critical density and large density gradients, while electrical diagnostics have limited spatial resolution. We report the first demonstration of proton deflectometry of z-pinch plasma systems at the mega-ampere scale. The proton beam was produced using the 10J 0.3ps Leopard laser and coupled to z-pinch plasma produced by Zebra, a 1MA pulsed-power driver at the Nevada Terawatt Facility. The magnetic field distorted the proton beam profile, which was recorded on radiochromic film. The experimental data was compared against integrated modeling using the resistive MHD code, Gorgon, for Z-pinch plasmas, in combination with the hybrid PIC code, LSP, for proton-beam trajectory tracking. This comparison provided the field and current configuration for various plasma loads, including wire and foil z-pinches. Funded by the NSF/DoE Partnership in Basic Plasma Scienceand En- gineering under contracts DE-SC-0001992 / PHY-0903876. Use of the Nevada Terawatt Facility was supported by the US DOE, NNSA, under Contract No. DE-FC52-06NA27616.

  6. PBFA Z: A 60-TW/5-MJ Z-pinch driver

    International Nuclear Information System (INIS)

    PBFA Z, a new 60-TW/5-MJ electrical accelerator located at Sandia National Laboratories, is now the world's most powerful z-pinch driver. PBFA Z stores 11.4 MJ in its 36 Marx generators, couples 5 MJ into a 60-TW/105-ns FWHM pulse to the 120-mΩ water transmission lines, and delivers 3.0 MJ and 50 TW of electrical energy to the z-pinch load. Depending on load parameters, we attain peak load currents of 16-20 MA with a current rise time of ∼105ns with wire-array z-pinch loads. We have extended the x-ray performance of tungsten wire-array z pinches from earlier Saturn experiments. Using a 2-cm-radius, 2-cm-long tungsten wire array with 240, 7.5-μm diameter wires (4.1-mg mass), we achieved an x-ray power of 210 TW and an x-ray energy of 1.9 MJ. Preliminary spectral measurements suggest a mostly optically-thick, Planckian-like radiator below 1000 eV. Data indicate ∼100kJ of x rays radiated above 1000 eV. An intense z-pinch x-ray source with an overall coupling efficiency greater than 15% has been demonstrated. copyright 1997 American Institute of Physics

  7. PBFA Z: A 60-TW/5-MJ Z-pinch driver

    International Nuclear Information System (INIS)

    PBFA Z, a new 60-TW/5-MJ electrical accelerator located at Sandia National Laboratories, is now the world's most powerful z-pinch driver. PBFA Z stores 11.4 MJ in its 36 Marx generators, couples 5 MJ into a 60-TW/105-ns FWHM pulse to the 120-mΩ water transmission lines, and delivers 3.0 MJ and 50 TW of electrical energy to the z-pinch load. Depending on load parameters, we attain peak load currents of 16-20 MA with a current rise time of ∼105 ns with wire-array z-pinch loads. We have extended the x-ray performance of tungsten wire-array z pinches from earlier Saturn experiments. Using a 2-cm-radius, 2-cm-long tungsten wire array with 240, 7.5-μm diameter wires (4.1-mg mass), we achieved an x-ray power of 210 TW and an x-ray energy of 1.9 MJ. Preliminary spectral measurements suggest a mostly optically-thick, Planckian-like radiator below 1000 eV. Data indicate ∼100 kJ of x rays radiated above 1000 eV. An intense z-pinch x-ray source with an overall coupling efficiency greater than 15% has been demonstrated

  8. On the Decay of the Longitudinal Current in Toroidal Screw Pinches

    International Nuclear Information System (INIS)

    In toroidal screw pinch experiments in Garching and in Jutphaas the longitudinal plasma current is observed to decay rapidly, which leads to a loss of equilibrium or to instability. Several causes for this decay are listed. The problem of the matching of a decaying pinch to the external circuits is discussed. External losses in the z-circuit give rise to currents in the plasma near the wall and thereby to an enhanced decay of the net longitudinal plasma current. Losses in the θ-circuit, however, tend to increase the longitudinal current. Also the volume currents flowing in a combined pinch lead to a transfer of energy from one field component to the other; calculations are given for a uniform-pitch screw pinch. A toroidal screw pinch will oscillate around its eccentric equilibrium position. The oscillation may force field lines into the wall and decrease thereby the plasma current. This effect diminishes when the external inductances in the z-circuit are small. At this stage it is not possible to conclude what cause or causes are responsible for the decay of the plasma current; further experimental and theoretical studies are therefore needed. (author)

  9. The influence of the self-consistent mode structure on the Coriolis pinch effect

    International Nuclear Information System (INIS)

    This paper discusses the effect of the mode structure on the Coriolis pinch effect [A. G. Peeters, C. Angioni, and D. Strintzi, Phys. Rev. Lett. 98, 265003 (2007)]. It is shown that the Coriolis drift effect can be compensated for by a finite parallel wave vector, resulting in a reduced momentum pinch velocity. Gyrokinetic simulations in full toroidal geometry reveal that parallel dynamics effectively removes the Coriolis pinch for the case of adiabatic electrons, while the compensation due to the parallel dynamics is incomplete for the case of kinetic electrons, resulting in a finite pinch velocity. The finite flux in the case of kinetic electrons is interpreted to be related to the electron trapping, which prevents a strong asymmetry in the electrostatic potential with respect to the low field side position. The physics picture developed here leads to the discovery and explanation of two unexpected effects: First the pinch velocity scales with the trapped particle fraction (root of the inverse aspect ratio), and second there is no strong collisionality dependence. The latter is related to the role of the trapped electrons, which retain some symmetry in the eigenmode, but play no role in the perturbed parallel velocity.

  10. Flow shear stabilization experiments in the ZaP flow Z-pinch

    International Nuclear Information System (INIS)

    The stabilizing effect of an axial flow on the m = 1 kink instability in Z-pinches has been studied numerically with a linearized ideal MHD model to reveal that a sheared axial flow stabilizes the kink mode when the shear exceeds a threshold. The sheared flow stabilizing effect is investigated with the ZaP Flow Z- pinch experiment. An azimuthal array of surface mounted magnetic probes located at the midplane of the 50 cm plasma column measures the fluctuation levels of the azimuthal modes m = 1, 2, and 3. After pinch assembly a quiescent period is found where the mode activity is significantly reduced. The quiescent period lasts for over 700 times the expected instability growth time in a static Z-pinch. Optical images from a fast framing camera and a ruby holographic interferometer indicate a stable, discrete pinch plasma during this time. Multichord Doppler shift measurements of impurity lines show a large, sheared flow during the quiescent period and low, uniform flow profiles during periods of high mode activity. The value of the velocity shear satisfies the theoretical threshold for stability during the quiescent period and does not satisfy the threshold during the high mode activity. (author)

  11. Axial behaviors of a theta pinch plasma with an antiparallel trapped magnetic field

    International Nuclear Information System (INIS)

    Fundamental plasma behavior has been almost revealed for theta pinch method in the researches for realizing controlled fusion reactions. Interest is also being taken in the axial behavior of plasma under such condition that the direction of the line of magnetic force confined in a pinched plasma column is reversed in relation to external magnetic field. The authors examined the axial behavior of linear theta pinch plasma with a high speed camera using the image converter tube RCA-4449A and the magnetic probe, and succeeded in photographing the details of plasma shape and its change with time. The experimental results and examinations are described in detail with the outline of experimental apparatuses, and summarized as follows. Area waves in compressional wave mode were observed during a second half cycle of discharge current, and the measured value of their propagation speed coincided with the calculated value. Collision of area waves at the center of the coil did not give the effect to annihilate the antiparallel field. Antiparalllel field arrangement, in which the location of zero magnetic field exists in pinch plasma, presents interesting problems such as heating and the stability in torus system in addition to the phenomena of area waves. The study with toroidal pinch will be a future research subject. (Wakatsuki, Y.)

  12. Dendrite fragmentation in alloy solidification due to sidearm pinch-off.

    Science.gov (United States)

    Neumann-Heyme, H; Eckert, K; Beckermann, C

    2015-12-01

    Dendrite sidebranch detachment is an important fragmentation mechanism during the solidification of alloys. The detachment occurs at the junction between a sidearm and its parent stem. While this pinching process is driven by capillarity, the presence of solidification opposes the instability. Using a simple numerical model of a single sidearm, we are able to capture the essential dynamics of dendrite sidebranch development and the resulting morphological transitions. While shortly before pinch-off the neck itself obeys well-known universal scaling relations, the overall evolution of the sidearm shape sensitively depends on its initial geometry and the rate of solidification. It is found that pinch-off only occurs over limited ranges of geometrical parameters and cooling rates and is generally bounded by sidearm retraction and coalescence regimes. Simple scaling relations are identified that provide the bounds for the pinch-off regime. Pinching at the branching point is shown to be faster than the Rayleigh-Plateau instability of an infinitely long cylinder. PMID:26764615

  13. Equation-of-State Measurements with Z-Pinch Sources

    International Nuclear Information System (INIS)

    Validation of material models in a variety of scientific and technological applications requires accurate data regarding the high-pressure thermodynamic and mechanical properties. Traditional laboratory techniques for striking these measurements involve light gas guns to generate the required thermodynamic states, and the use of high-resolution time-resolved diagnostics to measure the desired material properties. EOS and constitutive material properties of importance to modeling needs include high-pressure Hugoniot curves and off-Hugoniot properties, such as. material strength and isentropic compression and decompression [1]. Conventional light gas guns are limited to impact pressures of about 7 Mbar in high-impedance materials. Pulsed radiation sources, such as high-intensity lasers, and pulsed power techniques significantly extend the accessible pressures and are becoming accepted methods for meeting the needs of material models in regimes inaccessible by gas guns. A present limitation of these new approaches is that samples must necessarily be small, typically a few tens of microns in thickness, which severely limits the accuracy of EOS measurements that can be made and also the ability to perform a variety of off-Hugoniot measurements. However, recent advances in z-pinch techniques for high-pressure material response studies provide potential opportunities for achieving accuracies comparable with gas guns because of the significantly larger samples that can be studied. Sample thicknesses approaching 1 mm may be possible with advances presently being made. These sample dimensions are comparable with gas gun sample dimensions so that accuracies should be comparable. The Sandia Z accelerator [2] is a recently developed facility that generates x-ray energies of about 2 MJ over time scales of 5-10 ns with resulting temperatures of 100-150 eV in containment fixtures, referred to as hohlraums, that are a few cubic centimeters in volume. This intense radiation source

  14. Study of the stability of Z-pinch implosions with different initial density profiles

    Energy Technology Data Exchange (ETDEWEB)

    Rousskikh, A. G.; Zhigalin, A. S.; Labetskaya, N. A.; Chaikovsky, S. A.; Yushkov, G. Yu. [Institute of High Current Electronics of the Siberian Branch of the Russian Academy of Sciences, Tomsk (Russian Federation); Oreshkin, V. I.; Batrakov, A. V. [Institute of High Current Electronics of the Siberian Branch of the Russian Academy of Sciences, Tomsk (Russian Federation); Tomsk Polytechnic University, Tomsk (Russian Federation); Baksht, R. B. [Institute of High Current Electronics of the Siberian Branch of the Russian Academy of Sciences, Tomsk (Russian Federation); Tel-Aviv University, Tel Aviv (Israel)

    2014-05-15

    Stability of metal-puff Z pinches was studied experimentally. Experiments were carried out on a facility producing a load current up to 450 kA with a rise time of 450 ns. In a metal-puff Z pinch, the plasma shell is produced due to evaporation of the electrode material during the operation of a vacuum arc. In the experiment to be reported, a single-shell and a shell-on-jet pinch load with magnesium electrodes were used. Two-dimensional, 3 ns gated, visible-light images were taken at different times during the implosion. When the shell was formed from a collimated plasma flow with small radial divergence, Rayleigh–Taylor (RT) instability typical of gas-puff implosions was recorded. The RT instability was completely suppressed in a mode where the initial density distribution of the shell approached a tailored density profile [A. L. Velikovich et al., Phys. Rev. Lett. 77, 853 (1996)].

  15. Kinetic theory of the sausage instability of a z-pinch

    International Nuclear Information System (INIS)

    A linear problem of z-pinch sausage development is considered taking into account the influence of kinetic effects for ideal scanning current. Plasma electrons are considered to be cold and ions - collisionless. It is also supposed that the magnetic field inside a pinch doesn't affect the motion of ions, which are reflected like in a mirror from a jump of an electric potential arising on the plasma boundary. In case of long-wave perturbations ka>1 the acount of kinetics leads to considerable decrease of the increment [(ka)1/2 times] in comparison with the hydrodynamic description, that permits to explain the increased instability of z-pinches observed in experiments

  16. Identification of the ubiquitous Coriolis momentum pinch in JET tokamak plasmas

    International Nuclear Information System (INIS)

    A broad survey of the experimental database of neutral beam heated plasmas in the JET tokamak has established the theoretically expected ubiquity, in rotating plasmas, of a convective transport mechanism which has its origin in the vertical particle drift resulting from the Coriolis force. This inward convection, or pinch, leads to inward transport of toroidal angular momentum and is characterized by pinch numbers RV/χφ, which rise from near unity at r/a ≈ 0.25 to around 5 at r/a ≈ 0.85. Linear gyrokinetic calculations of the Coriolis pinch number and the Prandtl number χφ/χi are in good agreement with the experimental observations, with similar dependences on plasma parameters. The data, however, do not rule out contributions from different processes, such as residual stresses. (letter)

  17. Mitigation Effect of Finite Larmor Radius on Rayleigh-Taylor Instability in Z-Pinch Implosions

    Institute of Scientific and Technical Information of China (English)

    邱孝明; 黄林; 简广德

    2002-01-01

    Based on the framework of magnetohydrodynamic theory, a simple model is proposed to study the mitigation effect of finite Larmor radius on the Rayleigh-Taylor instability in Z-pinch implosions. In this model, taking account of Ti ≥ Te in Z-pinch implosions we believe that the magnetohydrodynamic plasma responds to a perturbation (~ exp [i (k. x - ωt)]) at frequency (ω + ik2⊥ρ2iΩi) instead of frequency ω, where k2⊥ρ2i is due to the finite Larmor radius effects expressed from the generalkinetic theory of magnetized plasma. Therefore the linearized continuity and momentum equations for the perturbed mass-density and velocity include the finite Larmor radius effects. The calculations indicate that, in the wavenumber region of interest, the finite Larmor radius effects can mitigate the Rayleigh-Taylor instability in Z-pinch implosions.

  18. Characterization of aluminum x-pinch plasmas driven by the 0.5 TW Lion accelerator

    International Nuclear Information System (INIS)

    The x-pinch, obtained by crossing two fine wires at one or more points as the load for the 0.5 TW Lion accelerator, has been used as a bright x-ray source. High density and temperature hot spots are observed at the crossing point(s). From these hot spots, an intense, spatially confined burst of x-rays is emitted which can serve as a pump for resonant photo-pumping lasers. The authors present experimental results concerning the radiation emission using Al x-pinches. The optimum mass loading for different ionization stages of Al ions and the total x-ray energy yields are examined. The density and temperature of the plasma and the size of the hot spots are measures. Based upon the results of these experiments, the authors evaluate resonant photopumping schemes such as those involving Be-like ions, using the Al x-pinch emission as the pump source

  19. Clinical Observation of Infantile Persisting Diarrhea Treated by Spine-Pinching Manipulation plus Moxibustion

    Institute of Scientific and Technical Information of China (English)

    WANG Juan-yi; LIU Wei-di; LIU Chun-mei; HUANG Guo-qi

    2003-01-01

    Purpose: To observe the clinical therapeutic effect in the treatment of infantile persisting diarrhea with the spine-pinching manipulation plus moxibustion.Methods: 110 cases of the sick children were randomly divided into 68 cases in the treatment group and 42 cases in the control group for comparative observation. The treatment group was treated by the spine-pinching manipulation and the control group was given the expectant treatment of western medicine. Results: The total effective rates were 97.0% and 81.0% in the treatment group and control group respectively, and the therapeutic effect in the treatment was better group than in the control group (P<0.01). Conclusion: The treatment of infantile persisting diarrhea by the spine-pinching manipulation plus moxibustion could remarkably enhance the therapeutic effect and shorten the courses of the treatment.

  20. Observation on the Therapeutic Effect of Vertigo Treated by Pinching the Spine

    Institute of Scientific and Technical Information of China (English)

    SHEN Qun; ZHU Zhong-chun

    2003-01-01

    Objective: To observe the therapeutic effect of vertigo treated by pinching the spine. Methods: In the treatment group, 80 cases of vertigo were treated by pinching the spine and An-pressing and Rou-stationary circular pressing. In the control group, 66 cases were treated by An-pressing and Rou-stationary circular pressing. Results: The total effective rate was 95.0% in the treatment group, and 66.7% in control group. The therapeutic effect in treatment group was better than that in control group (P<0.01). Conclusions: Pinching the spine to treat the vertigo could get rapid and good therapeutic effect, and may avoid the toxic and side effect of drug treatment.

  1. Pinch-off of axisymmetric vortex pairs in the limit of vanishing vortex line curvature

    Science.gov (United States)

    Sadri, V.; Krueger, P. S.

    2016-07-01

    Pinch-off of axisymmetric vortex pairs generated by flow between concentric cylinders with radial separation ΔR was studied numerically and compared with planar vortex dipole behavior. The axisymmetric case approaches planar vortex dipole behavior in the limit of vanishing ΔR. The flow was simulated at a jet Reynolds number of 1000 (based on ΔR and the jet velocity), jet pulse length-to-gap ratio ( /L Δ R ) in the range 10-20, and gap-to-outer radius ratio ( /Δ R R o ) in the range 0.01-0.1. Contrary to investigations of strictly planar flows, vortex pinch-off was observed for all gap sizes investigated. This difference was attributed to the less constrained geometry considered, suggesting that even very small amounts of vortex line curvature and/or vortex stretching may disrupt the absence of pinch-off observed in strictly planar vortex dipoles.

  2. Application of 2-D Simulations to Z-Pinch Experiment Design and Analysis

    International Nuclear Information System (INIS)

    The successful 2-D simulations of z-pinch experiments (reproducing such features as the measured experimental current drive, radiation pulse shape, peak power and total radiated energy) can lead to a better understanding of the underlying physics in z-pinch implosions and to the opportunity to use such simulations in the analysis of experimental data and in the design of new experiments. Such use has been made with LANL simulations of experiments on the Sandia Saturn and Z accelerators. Applications have included ''vacuum'' and ''dynamic'' hohlraum experiments; variations in mass, radius and length; and ''nested'' array configurations. Notable examples include the explanation of the power/length results in reduced length pinches and the prediction of the current best power and pulsewidth nested array experiment. Examples of circumstances where the simulation results do not match the experiments will be given along with a discussion of opportunities for improved simulation results

  3. Behavior of the reversed field pinch with nonideal boundary conditions

    International Nuclear Information System (INIS)

    The linear and nonlinear magnetohydrodynamic stability of current-driven modes are studied for a reversed field pinch with nonideal boundary conditions. The plasma is bounded by a thin resistive shell surrounded by a vacuum region out to a radius at which a perfectly conducting wall is situated. The distant wall and the thin shell problems are studied by removing either the resistive shell or the conducting wall. Linearly, growth rates of tearing modes and kink modes are calculated by analytical solutions based on the modified Bessel function model for the equilibrium. The effects of variation of the shell resistivity and wall proximity on the growth rates are investigated. The modes that may be important in different parameter regimes and with different boundary conditions are identified. The nonlinear behaviors are studied with a three-dimensional magnetohydrodynamics code. The fluctuations generally rise with increasing distance between the conducting wall and the plasma. The enhanced fluctuation induced v x b electric field primarily oppose toroidal current; hence, loop voltage must increase to sustain the constant. Quasilinear interaction between modes typically associated with the dynamo action is identified as the most probable nonlinear destabilization mechanism. The helicity and energy balance properties of the simulation results are discussed. The interruption of current density along field lines intersecting the resistive shell is shown to lead to surface helicity leakage. This effect is intimately tied to stability, as fluctuation induced v x b electric field is necessary to transport the helicity to the surface. In this manner, all aspects of helicity balance, i.e., injection, transport, and dissipation, are considered self-consistently. The importance of the helicity and energy dissipation by the mean components of the magnetic field and current density is discussed. 88 refs., 41 figs., 3 tabs

  4. The TITAN Reversed-Field Pinch fusion reactor study

    International Nuclear Information System (INIS)

    The TITAN Reversed-Field Pinch (RFP) fusion reactor study is a multi-institutional research effort to determine the technical feasibility and key developmental issues of an RFP fusion reactor, especially at high power density, and to determine the potential economics, operations, safety, and environmental features of high-mass-power-density fusion systems. The TITAN conceptual designs are DT burning, 1000 MWe power reactors based on the RFP confinement concept. The designs are compact, have a high neutron wall loading of 18 MW/m2 and a mass power density of 700 kWe/tonne. The inherent characteristics of the RFP confinement concept make fusion reactors with such a high mass power density possible. Two different detailed designs have emerged: the TITAN-I lithium-vanadium design, incorporating the integrated-blanket-coil concept; and the TITAN-II aqueous loop-in-pool design with ferritic steel structure. This report contains a collection of 16 papers on the results of the TITAN study which were presented at the International Symposium on Fusion Nuclear Technology. This collection describes the TITAN research effort, and specifically the TITAN-I and TITAN-II designs, summarizing the major results, the key technical issues, and the central conclusions and recommendations. Overall, the basic conclusions are that high-mass power-density fusion reactors appear to be technically feasible even with neutron wall loadings up to 20 MW/m2; that single-piece maintenance of the FPC is possible and advantageous; that the economics of the reactor is enhanced by its compactness; and the safety and environmental features need not to be sacrificed in high-power-density designs. The fact that two design approaches have emerged, and others may also be possible, in some sense indicates the robustness of the general findings

  5. Z-pinch of an annular gas jet

    International Nuclear Information System (INIS)

    The implosion and thermalization of an annular argon plasma is investigated. The plasma is produced by the z-pinch of an annular jet of argon gas, using a marx bank-transmission line system which delivers a peak current of 415 kA in 200 ns. The annulus implodes from its initial diameter of 2.5 cm and reaches a peak velocity of approx.2.8 x 107 cm/sec. Measurements of the plasma's radius, thickness, electron density, and average ionization state as a function of time are performed. When the imploding plasma reaches the axis, an 8 ns pulse of soft (0.1-1 keV) x rays is emitted. X rays with energies between 1 and 6 keV are also observed, and are emitted in a single pulse 2 to 5 ns wide. The thermalized plasma is inhomogeneous along the axial direction; vacuum ultraviolet spectroscopy indicates that some regions are approx.270 eV, with Ar XIV in abundance, while x-ray spectroscopy indicates that other regions of the plasma have only highly ionized argon (XVI-XVIII). Although a thermal interpretation of the x-ray spectra would indicate an electron temperature of approx.1 keV, there is evidence that an energetic beam of electrons develops in the thermalized plasma. When this beam is included in the analysis of the x-ray spectra, it is found that the temperature in the hot spots could be as low as 400 eV. The electron density in the thermalized plasma is estimated to be greater than or equal to 1020 cm-3

  6. Analisis Kinerja Operasional Kereta Api Sriwedari Ekspress Jurusan Solo - Yogya

    Directory of Open Access Journals (Sweden)

    Bayu Rosida Sumantri

    2014-03-01

    Full Text Available Pada bulan Nopember 2012 PT. Kereta Api Indonesia (Persero DAOP 6 Yogyakarta mengoperasikan Kereta Api Sriwedari Ekspress dengan rute perjalanan Yogya – Solo, hal ini dilakukan untuk mengantisipasi lonjakan penumpang akibat pemangkasan rute perjalanan Kereta Api Prambanan Ekspress dari tiga belas kali perjalanan menjadi enam kali perjalanan. Menurut Humas PT. Kereta Api Indonesia (Persero DAOP 6 Yogyakarta, dibukanya rute baru Kereta Api Sriwedari Ekspress yang melayani delapan kali perjalanan hanya  dengan rute Yogya – Solo saja diharapkan kereta ini dapat memfasilitasi pergerakan penumpang antar dua daerah tersebut. Namun untuk mengetahui kinerja dari kereta api ini sesuai dengan Surat Keterangan Dirjen Perhubungan Darat No. 687 Tahun 2002, perlu ditinjau dari segi faktor muat, jumlah penumpang yang diangkut, waktu tunggu penumpang, ketepatan waktu kedatangan dan keberangkatan kereta dan kenyamanan penumpang. Dalam penelitian digunakan metode survey untuk mendapatkan nilai – nilai dari kinerja kereta api Sriwedari berupa survey observasi atau pengamatan lapangan.  Adapun  analisis yang digunakan untuk perhitungan waktu tempuh, waktu henti dan waktu tunda menggunakan uji hipotesis 1 sample t-test, karena uji ini paling memenuhi untuk melihat diterima atau tidaknya keterlambatan dari waktu kereta. Sedangkan untuk perhitungan load factor dan kenyamanan duduk dan berdiri berdasarkan perhitungan kapasitas dari Vukan R. Vuchic. Dari hasil analisis didapatkan waktu tempuh rata-rata untuk arah Yogyakarta selama 1 jam 14 menit dan untuk arah Solo selama 1 jam 12 menit. Waktu henti yang didapat dari seluruh jadwal perjalanan kereta arah Yogyakarta sebesar 3 menit, untuk arah Solo sebesar 5 menit. Waktu tunda dari seluruh perjalanan kereta Api Sriwedari untuk arah Yogyakarta didapat nilai waktu tunda kedatangan sebesar 22 menit dan nilai waktu tunda keberangkatan sebesar 20 menit, untuk arah Solo didapat nilai waktu tunda kedatangan sebesar 34

  7. Analisis komoditas unggulan perikanan budidaya Kabupaten Pidie Jaya

    Directory of Open Access Journals (Sweden)

    Farok Afero

    2015-06-01

    Full Text Available Abstract. Snapper (Lates calcarifer, grouper (Epinephelus coioides, tiger shrimp (Penaeus monodon, vannamei shrimp (Litopenaeus vannamei and tilapia (Oreochromis niloticus are leading commodity worthly cultivated in Pidie Jaya. Bandar Baru and Tringgadeng an appropriate areas for black tiger shrimp while Jangka Buya and Ulim approriate areas for vannamei cultivation. AHP analysis showed black tiger shrimp is top priority based on the economic value while vannamei shrimp is top priority based on enterprise sustainability. Financial analysis of snapper, grouper, black tiger shrimp, vannamei shrimp and tilapia farming generated positive cash flow and NPV, IRR > 100%, the ratio of benefit to cost of production > 1,30 and payback period of investment costs  < 1 year, thus demonstrating the feasibility of cultivation of these leading commodities. Vannamei shrimp cultivation showed positive prospect as long the market offers premium price. Grouper and snapper had a positive outlook because high demand of high-quality fish in the international market. Keywords: Leading commodity; financial analysis; aquaculture; Pidie Jaya Abstrak. Komoditas kakap (Lates calcarifer, kerapu (Epinephelus coioides,udang windu (Penaeus monodon, udang vannamei (Litopenaeus vannamei dan nila (Oreochromis niloticus adalah komoditas unggulan yang layak dibudidaya di Kabupaten Pidie Jaya. Bandar Baru dan Tringgadeng merupakan kawasan yang layak untuk pengembangan komoditas udang windu sedangkan Jangka Buya dan Ulim layak untuk pengembangan komoditas udang vannamei. Analisis AHP menunjukkan komoditas udang windu menjadi prioritas utama untuk dikembangkan berdasarkan nilai ekonomi sedangkan udang vannamei menjadi prioritas utama berdasarkan keberlanjutan usaha. Analisis indikator keuangan budidaya kakap, kerapu, udang windu, vannamei dan nila menunjukkan usaha budidaya komoditas unggulan menghasilkan arus kas kumulatif dan NPV positif, nilai  IRR diatas 100%, rasio keuntungan

  8. Stabilization of long wavelength sausage and kink modes of a Z-pinch by nonlinear radial oscillations

    International Nuclear Information System (INIS)

    A number of experiments with fiber-initiated dense Z-pinches, with compressional and gas-embedded Z-pinches, with imploding gas-puff Z-pinches and the straight Extrap configuration performed in the last decade demonstrated sufficiently improved stability of Z-pinch configurations. The striking stability with respect to the sausage modes can be explained, in principle, by ideal MHD theory as well as by finite plasma conductivity effects. The global kink mode can not be stabilized by the appropriate choice of the unperturbed profiles neither within the scope of the ideal MHD nor taking into account finite ion Larmor radius and viscous damping effects. In this report we shall demonstrate that stabilization of the global kink modes can be explained by the assumption that pinch is not in a stationary but in a dynamic equilibrium. (author) 12 refs., 2 figs

  9. Toroidal Momentum Pinch Velocity due to the Coriolis Drift Effect on Small Scale Instabilities in a Toroidal Plasma

    International Nuclear Information System (INIS)

    In this Letter, the influence of the ''Coriolis drift'' on small scale instabilities in toroidal plasmas is shown to generate a toroidal momentum pinch velocity. Such a pinch results because the Coriolis drift generates a coupling between the density and temperature perturbations on the one hand and the perturbed parallel flow velocity on the other. A simple fluid model is used to highlight the physics mechanism and gyro-kinetic calculations are performed to accurately assess the magnitude of the pinch. The derived pinch velocity leads to a radial gradient of the toroidal velocity profile even in the absence of a torque on the plasma and is predicted to generate a peaking of the toroidal velocity profile similar to the peaking of the density profile. Finally, the pinch also affects the interpretation of current experiments

  10. High yield inertial fusion design for a z-pinch accelerator

    International Nuclear Information System (INIS)

    In this paper we discuss design calculations for high yield inertial fusion capsules, indirectly driven by a double-ended z-pinch-driven hohlraum radiation source. The z-pinches are imploded by a high current (- 60 MA) accelerator while enclosed within a hohlraum. Radial spoke arrays and shine shields isolate the capsule from the pinch plasma, magnetic field and direct x-ray shine. Our approach places minimal requirements on z-pinch uniformity and stability, usually problematic due to magneto- Rayleigh Taylor (MRT) instability. The hohlraum smooths the radiation field at the capsule, even in the presence of large millimeter scale inhomogeneities of the pinch and the high-spatial-frequency pertur- bation of the spoke array. The design requires simultaneity and reproducibility of the x-ray output to 5- 10%, however. Reproducibility at this level may be achievable based on experience with the Z and Sat- urn accelerators. Recent Z experiments also suggest a method for generating the required x-ray pulse shape, through implosion of a multi-shell z-pinch. X-ray bursts are calculated and observed to occur at each shell collision. Variation of shell masses and radii allows considerable latitude for creating the desired pulse shape. For the design considered, a capsule absorbing 1 MJ of x-rays at a peak drive tem- perature of 210 eV is found to have adequate stability and produces 400 MJ of yield. A larger capsule with slightly longer drive and similar peak temperature absorbs 2 MJ with a yield of 1200 MJ

  11. Equilibrium evolution in the ZaP flow Z-pinch

    International Nuclear Information System (INIS)

    The ZaP Flow Z-pinch experiment at the University of Washington investigates the innovative plasma confinement concept of using sheared flows to stabilize an otherwise unstable configuration. The stabilizing effect of a sheared axial flow on the m = 1 kink instability in Z-pinches has been studied using linearized, ideal MHD theory to reveal that a sheared axial flow stabilizes the kink mode when the shear exceeds a threshold. The ZaP experiment generates an axially flowing Z-pinch that is 1 m long with a 1 cm radius with a coaxial accelerator coupled to a pinch assembly chamber. Magnetic probes measure the fluctuation levels of the azimuthal modes m = 1, 2, and 3. After assembly the plasma is magnetically confined for an extended quiescent period where the mode activity is significantly reduced. Time-resolved Doppler shifts of plasma impurity lines are measured along 20 chords to determine the plasma axial velocity profiles showing a large, but sub-Alfvenic, sheared flow during the quiescent period and low shear profiles during periods of high mode activity. The plasma has a sheared axial flow that exceeds the theoretical threshold for stability during the quiescent period and is lower than the threshold during periods of high mode activity. The sheared flow profile is coincident with a plasma quiescent period where magnetic mode fluctuations are low. The value of the velocity shear satisfies the theoretical threshold for stability during the quiescent period and does not satisfy the threshold during high mode activity. Multichord and holographic interferometers measure a Z-pinch plasma with a peaked radial profile during the quiescent period. Internal magnetic fields have been recently determined by measuring the Zeeman splitting of impurity carbon emission. The measurements are consistent with a well-confined pinch plasma. (author)

  12. Design of the PST: A Diagnostic for 1-D Imaging of Fast Z-Pinch Power Emissions

    International Nuclear Information System (INIS)

    Fast Z-pinch technology developed on the Z machine at Sandia National Laboratories can produce up to 230 TW of thermal x-ray power for applications in inertial confinement fusion (ICF) and weapons physics experiments. During implosion, these Z-pinches develop Rayleigh-Taylor (R-T) instabilities which are very difficult to diagnose and which functionally diminish the overall pinch quality. The Power-Space-Time (PST) instrument is a newly configured diagnostic for measuring the pinch power as a function of both space and time in a Z-pinch. Placing the diagnostic at 90 degrees from the Z-pinch axis, the PST provides a new capability in collecting experimental data on R-T characteristics for making meaningful comparisons to magneto-hydrodynamic computer models. This paper is a summary of the PST diagnostic design. By slit-imaging the Z-pinch x-ray emissions onto a linear scintillator/fiber-optic array coupled to a streak camera system, the PST can achieve ∼100 microm spatial resolution and ∼1.3 ns time resolution. Calculations indicate that a 20 microm thick scintillating detection element filtered by 1,000 angstrom of Al is theoretically linear in response to Plankian x-ray distributions corresponding to plasma temperatures from 40 eV to 150 eV, By calibrating this detection element to x-ray energies up to 5,000 eV, the PST can provide pinch power as a function of height and time in a Z-pinch for temperatures ranging from ∼40 eV to ∼400 eV. With these system pm-meters, the PST can provide data for an experimental determination of the R-T mode number, amplitude, and growth rate during the late-time pinch implosion

  13. Recent Improvements to MACH2 and MACH3 For Fast Z-Pinch Modeling

    Science.gov (United States)

    Frese, Sherry D.; Frese, Michael H.

    2002-12-01

    Many recent changes in MACH2 have improved the code's accuracy and speed in Z-pinch simulations. New code diagnostics monitoring energy are also useful in running the code efficiently. The changes to MACH3 are less numerous, though they are more sweeping: MACH3's grid is now truly three-dimensional and composed of a multiblock structure of arbitrary hexahedral zones; its difference equations have been upgraded to that new mesh. These new capabilities are currently being applied to wire-array Z-pinch problems.

  14. Investigation of turbulence in reversed field pinch plasma by using microwave imaging reflectometry

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Z. B. [Graduate University for Advanced Studies, Toki 509-5292 (Japan); Southwestern Institute of Physics, Chengdu 610041 (China); Nagayama, Y.; Hamada, Y. [National Institute for Fusion Science, Toki 509-5292 (Japan); Yamaguchi, S. [Kansai University, Suita 564-8680 (Japan); Hirano, Y.; Kiyama, S.; Koguchi, H.; Sakakita, H. [Advanced Industrial Science and Technology, Tsukuba 305-8568 (Japan); Michael, C. A. [UKAEA, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Yambe, K. [Osaka University, Osaka 565-0871 (Japan)

    2011-10-15

    Turbulence in the reversed field pinch (RFP) plasma has been investigated by using the microwave imaging reflectometry in the toroidal pinch experiment RX (TPE-RX). In conventional RFP plasma, the fluctuations are dominated by the intermittent blob-like structures. These structures are accompanied with the generation of magnetic field, the strong turbulence, and high nonlinear coupling among the high and low k modes. The pulsed poloidal current drive operation, which improves the plasma confinement significantly, suppresses the dynamo, the turbulence, and the blob-like structures.

  15. Temporal characteristics of X-ray emission from X-pinches

    International Nuclear Information System (INIS)

    Paper presents the results of study of time characteristics of X-ray radiation from X-pinch. To record radiation one made use of diamond and silicon photodiodes with subnanosecond time resolution, as well as, X-ray and electron-optical chambers with picosecond time resolution. One investigated into radiation of various material (Al, Ti, Mo, W) X-pinches within 1-10 keV energy range. Duration of X-ray radiation for heavy elements is shown to be maximum 5-10 ps

  16. Analysis of x-ray spectra obtained in foam Z-pinch experiments

    International Nuclear Information System (INIS)

    Foam Z-pinch experiments have recently been performed on SATURN to study issues associated with the initiation, acceleration, and stagnation phases of the pinch. Time-integrated x-ray crystal spectra have been recorded from experiments with 5 mg/cc Si aerogel loads and 10 mg/cc agar loads. In this article, we describe results from collisional-radiative equilibrium calculations performed to analyze the Si, Na, and S K-shell emission observed in the spectra. Particular attention is paid to density and opacity effects on intensity ratios involving Heα, He intercombination, and Li-like satellite lines. copyright 1997 American Institute of Physics

  17. Creation of high-temperature plasma through the use of a superfast Z-pinch

    International Nuclear Information System (INIS)

    This thesis is a theoretical and computational study of plasma temperature generated during a superfast Z-pinch hydrogen plasma implosion-driven by a modern multi-terrawatt pulsed power source. The solution of the time-dependent, one-dimensional, initial-value problem used to study and describe the pinch process includes the effects of kinetic instabilities, anomalous collisionality, plasma heating, and all relevant energy-loss mechanisms. Two dimensional effects are estimated by using a modified form of the one-dimensional model

  18. Transition from Symmetric to Asymmetric Scaling Function before Drop Pinch-Off

    International Nuclear Information System (INIS)

    The drop pinch-off at a nozzle is studied experimentally for a glycerin-water mixture in surrounding air. The neck diameter of the fluid shrinks with constant velocity. After a distinct transition point, the shrink velocity switches to a smaller value. Before that transition point, the shape of the neck can well be described by a symmetric scaling function, as obtained from Stokes-flow theory of drop formation. This function gives way to an asymmetric scaling function in the final stage before pinch-off

  19. Plasma channel and Z-pinch dynamics for heavy ion transport

    Energy Technology Data Exchange (ETDEWEB)

    Ponce-Marquez, David

    2002-07-09

    A self stabilized, free standing, z-pinch plasma channel has been proposed to deliver the high intensity heavy ion beam from the end of a driver to the fuel target in a heavy ion inertial fusion power plant. The z-pinch relaxes emittance and energy spread requirements requiring a lower cost driver. A z-pinch transport would reduce the number of beam entry port holes to the target chamber from over a hundred to four as compared to neutralized ballistic focusing thus reducing the driver hardware exposure to neutron flux. Experiments where a double pulse discharge technique is used, z-pinch plasma channels with enhanced stability are achieved. Typical parameters are 7 kV pre-pulse discharge and 30 kV main bank discharge with 50 kA of channel current in a 7 torr background gas atmosphere. This work is an experimental study of these plasma channels examining the relevant physics necessary to understand and model such plasmas. Laser diagnostics measured the dynamical properties of neutrals and plasma. Schlieren and phase contrast techniques probe the pre-pulse gas dynamics and infrared interferometry and faraday effect polarimetry are used on the z-pinch to study its electron density and current distribution. Stability and repeatability of the z-pinch depend on the initial conditions set by the pre-pulse. Results show that the z-pinch channel is wall stabilized by an on-axis gas density depression created by the pre-pulse through hydrodynamic expansion where the ratio of the initial gas density to the final gas density is > 10/1. The low on-axis density favors avalanching along the desired path for the main bank discharge. Pinch time is around 2 s from the main bank discharge initiation with a FWHM of {approx} 2 cm. Results also show that typical main bank discharge plasma densities reach 10{sup 17} cm{sup -3} peak on axis for a 30 kV, 7 torr gas nitrogen discharge. Current rise time is limited by the circuit-channel inductance with the highest contribution to the

  20. ANALISIS PERANAN DAN DAMPAK INVESTASI INFRASTRUKTUR TERHADAP PEREKONOMIAN INDONESIA: ANALISIS INPUT-OUTPUT

    Directory of Open Access Journals (Sweden)

    Chandra Darma Permana

    2011-08-01

    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Despite being recovered from economic crisis, the infrastructure development in Indonesia still hasn’t shown a significant improvement. It is reflected from the diminishing government allocation for infrastructure as a percentage of Gross Domestic Products. The main objective of the study is to analyze the role of infrastructure through the linkage analysis, dispersion effect analysis, multiplier effect analysis, and the investment effect analysis. The scope of infrastructure is only referred to electricity, gas and water, and construction sector. The data used for this study is the 2005 Indonesian Input-Output Table. The result of the study has shown that infrastructure has a higher backward linkage than its forward. In addition, all of the infrastructure sectors has shown more than one dispersion coefficient and conversely has revealed less than one value for the dispersion sensitivity. Which means that infrastructure had a better capability to support the development of its upstream sectors than its downstream. Infrastructure has a positive multiplier effect toward the other sectors. The growth of the investment in the electricity, gas and water sector has given the biggest effect toward the change of the total outpu, while the water sector has given the biggest effect toward the change in the total income,  and road, bridge and port sector has given the biggest effect toward the change in the total labour.

  1. ANALISIS PENGARUH CORPORATE SOCIAL RESPONSIBILITY TERHADAP CITRA PERUSAHAAN ( STUDI KASUS PT. International Nickel Indonesia Tbk)

    OpenAIRE

    ULVA, -

    2012-01-01

    ULVA. Analisis Pengaruh Corporate Social Responsibility terhadap Citra Perusahaan (Studi Kasus PT. International Nickel Indonesia Tbk), di bawah bimbingan Drs. M. Ishak Amsari, M.Si, Ak dan Drs. Agus Bandang, M.Si, Ak. Kata Kunci : Corporate Social Responsibility, Citra Perusahaan Penelitian ini dilatarbelakangi oleh semakin berkembangnya perusahaan yang juga memunculkan akan kesadaran tanggung jawab sosial perusahaan terhadap lingkungan dan ...

  2. ANALISIS LABELLING PEREMPUAN DENGAN TEORI FEMINISME PSIKOANALISIS: STUDI KASUS MAJALAH REMAJA OLGA!

    OpenAIRE

    - Muashomah

    2013-01-01

    Labelling perempuan dalam majalah remaja merupakan salah satu tindakan media yang merugikan perempuan. Dalam tulisan ini, penulis mengkaji label-label perempuan, bentuk labelling, analisis teori feminisme psikoanalisis terhadap labelling untuk perempuan dalam majalah remaja. Dalam penelitian ini penulis menggunakan metode semiotik dan penelitian dilakukan terhadap majalah Olga. Hasil penelitian menunjukkan bahwa praktek pelabelan terhadap perempuan yang dilakukan oleh majalah remaja ditujukan...

  3. ANALISIS PENGARUH SEGMENTASI PASAR TERHADAP PENINGKATAN PENJUALAN PIPA PADA PT. RAJAWALI JAYA SAKTI DI MAKASSAR

    OpenAIRE

    JAFAR, MUTMAINNA

    2012-01-01

    Mutmainna Jafar. A 211 08 927. Analisis Pengaruh Segmentasi Pasar Terhadap Peningkatan Penjualan Pipa Pada PT. Rajawali Jaya Sakti di Makassar. (dibimbing oleh H. Muh Asdar dan Hj. Nuraeni Kadir) Penelitian ini bertujuan untuk untuk mengetahui pelaksanaan penetapan segmentasi pasar yang dilakukan oleh perusahaan PT. Rajawali Jaya Sakti di Makassar dalam peningkatan penjualan pipa dan untuk mengetahui pengaruh segmentasi pasar terh...

  4. ANALISIS PENGARUH KUALITAS FINANSIAL PERUSAHAAN, KUALITAS AUDITOR DAN KUALITAS PEREKONOMIAN TERHADAP OPINI AUDIT (GOING CONCERN)

    OpenAIRE

    Baqarina Hadori; Bambang Sudibyo

    2014-01-01

    Abstrak: Analisis Pengaruh Kualitas Finansial Perusahaan, Kualitas Auditor, Dan Kualitas Perekonomian Terhadap Opini Audit (Going Concern). Penelitian ini bertujuan untuk menguji pengaruh faktor keuangan dan faktor non-keuangan terhadap pemberian opini audit going concern oleh auditor. Faktor keuangan yang diuji adalah profitabilitas, likuiditas, solvabilitas, pertumbuhan penjualan tahunan, dan pertumbuhan harga saham. Sedangkan faktor non-keuangan yang diuji adalah kualitas auditor dan kuali...

  5. "Analisis Strategi Bauran Pemasaran Terhadap Penjualan Mobil Toyota Vios pada PT. Toyota Hadji Kalla Makassar"

    OpenAIRE

    SYAIFULLAH, ANDI

    2012-01-01

    Dalam penelitian yang berjudul Analisis Strategi Bauran Pemasaran terhadap penjualan mobil Toyota Vios pada PT.Toyota Hadji Kalla Makassar. Dianalisis tentang konsep bauran pemasaran yang dikaitkan dengan penjualan. Penelitian ini bertujuan untuk menganalisis pengaruh dari variabel produk, harga, promosi dan distribusi terhadap penjualan. Jumlah sampel yang digunakan dalam penelitian ini sebesar 54 orang responden yang ...

  6. Cinemateca de Vertigo. El delirio de la mirada: Vertigo (1958, Alfred Hitchcock) Analisis de una secuencia

    OpenAIRE

    Castro de Paz, José Luis

    1992-01-01

    Castro De Paz, JL. (1992). Cinemateca de Vertigo. El delirio de la mirada: Vertigo (1958, Alfred Hitchcock) Analisis de una secuencia. Vértigo. Revista de cine. (2):43-48. http://hdl.handle.net/10251/42923. 43 48 2

  7. Comprehensive energy analysis using the 'Pinch' method; Gesamtenergieanalyse mit der Pinch-Methode. Perlen Papier AG. Energie- und Produktionskostensenkung - Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, F.; Morand, R.

    2008-06-15

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made on the use of the 'Pinch' Method to lower energy and production costs in a paper mill in Perlen, Switzerland. The energy supply systems used in this manufacturing facility, which produces over 300,000 tonnes of paper products annually, are described. Two production lines were analysed using systematic 'Pinch' analysis. The savings in energy that could be made possible if measures indicated by the analysis were implemented are discussed. These include the optimisation of operating temperatures and heat recovery. The recommendations made are noted and priorities for the staged implementation of the measures recommended are stated.

  8. TWITTER: UN’ANALISI DELL’ITALIANO NEL MICRO BLOGGING

    Directory of Open Access Journals (Sweden)

    Cristina Zaga

    2012-07-01

    Full Text Available Il contributo è incentrato su un’analisi linguistica dell’italiano scritto nella piattaforma sociale e di micro blogging Twitter. Attraverso alcuni esempi estrapolati da un corpus di 2.150 di messaggi, chiamati tweet, si cerca di definire la tipologia testuale e di individuare i tratti sintattici e lessicali salienti del micro blogging. In particolare ci si sofferma su quelle dinamiche micro sintattiche auto generate dall’utenza (@reply, @mention, retweet e su quei tratti lessicali di organizzazione e costruzione di significato e senso condiviso (hashtag che concorrono a far emergere, tramite una dinamica “conversazionale - collaborativa” (definita tweetonomy, quella che si potrebbe definire una ”grammatica di Twitter”.TWITTER: A LINGUISTIC ANALYSIS OF ITALIAN LANGUAGE IN MCRO BLOGGINGThe following paper is a linguistic analysis of Italian language use in Twitter, a well-known micro blogging and social awareness platform.The main purpose describe and define the Italian Twitter texting genre in terms of syntax and vocabulary, providing several examples taken from a corpus of 2.150 tweets.The analysis focus on user-generated micro syntax forms (@reply, @mention, retweet and on user-generated conversational tagging (hashtags which seem to create, through collaborative-conversational dynamics (aka tweetonomy, a sort of “Twitter grammar”.

  9. Khutbah Jum’at Di Kota Samarinda (Analisis Kesiapan Para Khotib Di Kota Samarinda

    Directory of Open Access Journals (Sweden)

    M. Tahir

    2013-12-01

    Full Text Available Friday Khutbah is one of the Friday prayers at the same time as a form of da’wah. Khotib as a da’i and the congregation of Friday prayers as a proselytizing receiver. One thing that is undeniable in the implementation of the Khutbah is the tendency of the mosque congregation to move where the choosing of Khotib who able to give new nuances in his speech, although, he has to travel relatively far to find a sympathetic Khotib. Khutbah will be interesting if delivered with feeling and the involvement of Khotib with the issues discussed . To achieve high quality Khutbah, a Khotib needs a long process. He must constantly improve their knowledge, develop skills and expand his experience with continuous training. In addition, the power of creativity and style of well-groomed appearance will also contribute to determine the success of Khutbah.

  10. Probabilistic analysis of free ways for maintenance; Analisis probabilista de vias libres para mantenimiento

    Energy Technology Data Exchange (ETDEWEB)

    Torres V, A.; Rivero O, J.J. [Dpto. Ingenieria Nuclear, Instituto Superior de Tecnologias y Ciencias Aplicadas, Ave. Salvador Allende y Luaces, Quinta de los Molinos, Plaza, Ciudad Habana (Cuba)]. e-mail: atorres@fctn.isctn.edu.cu

    2004-07-01

    The safety during the maintenance interventions is treated in limited manner and in general independent of the systems of management of the maintenance. This variable is affected by multiple technical or human factors many times subjective and difficult to quantifying, what limits the design of preventive plans. However, some factors constitute common points: the isolation configurations during the free ways (bank drafts in the oil industry) and the human errors associated to their violation. This characteristic allowed to develop the analysis of such situations through the methodology of fault trees that it links faults of teams and human errors cohesively. The methodology has been automated inside the MOSEG Win Ver 1.0 code and the same one can embrace from the analysis of a particular situation of free way until that of a complete strategy of maintenance from the point of view of the safety of the maintenance personal. (Author)

  11. Indicators for knowledge transfer analysis; Indicadores para el analisis de la transferencia de conocimientos

    Energy Technology Data Exchange (ETDEWEB)

    Plaza, L. M.

    2007-07-01

    Understanding by knowledge transfer, the process by which the scientific knowledge generated by the R+Ds Spanish public system investigators is finally harnessed and officially used by the agents that make up the productive system, or by the administration; this project aims to offer a global view of the main scientific indicators by which said process can be analysed and in particular, of the way that some of these indicators allow us to evaluate this transfer in the case of the Spanish I+D system and in that concerning the Biotechnology sector. (Author) 12 refs.

  12. UN SOFTWARE COMO COMPLEMENTO PARA EL ANALISIS DE LA PRACTICA EXPERIMENTAL DEL PENDULO

    Directory of Open Access Journals (Sweden)

    OLGA LUCIA CASTIBLANCO ABRIL

    2010-08-01

    Full Text Available We present an application for the software “Geogebra” as a tool that it allow to study in depth a physical phenomenon, for this case the study about simple and coupled pendulum. The fundamental idea is to extract the major profit from the analysis by means of graphs that are very difficult to obtain if they become taking information directly of the experience, in order to this goal is necessary to consider reflections for re thinking the speech with which usually the topic is presented, allowing students for exposes his confusions or doubts. The aim is not offer exactly activities sequences in order that the teacher develops the class, but to offer elements for the teacher could re create his educational work.

  13. Analisis Forecasting Penawaran dan Permintaan Ekspor Biji Kakao (Theobroma cacao L.) Sumatera Utara ke Malaysia Tahun 2020

    OpenAIRE

    Atikah, Fadiah

    2016-01-01

    Tujuan penelitian ini adalah untuk menganalisis faktor-faktor yang mempengaruhi penawaran ekspor biji kakao Sumatera Utara, faktor-faktor yang mempengaruhi permintaan ekspor biji kakao Sumatera Utara ke Malaysia, dan proyeksi penawaran dan permintaan ekspor biji kakao Sumatera Utara ke Malaysia tahun 2020. Metode analisis yang digunakan dalam penelitian ini adalah analisis regresi linear berganda untuk menganalisis faktor-faktor yang mempengaruhi penawaran dan permintaan ekspor biji kakao ...

  14. Analisis Faktor-faktor Yang Mempengaruhi Dividend Payout Ratio Pada Industri Barang Konsumsi Di Bursa Efek Indonesia.

    OpenAIRE

    Ketaren, Roby Juahta

    2011-01-01

    Penelitian ini bertujuan untuk menguji dan menganalisis faktor-faktor yang mempengaruhi Dividend Payout Ratio pada industri barang konsumsi di Bursa Efek Indonesia. Pada penelitian ini digunakan analisis fundamental perusahaan melalui analisis rasio keuangan antara lain Cash Position (CP), Debt to Equity Ratio (DER), Return on Assets (ROA), Growth Potential (GP), Firm Size, dan Dividend Payout Ratio (DPR). Periode penelitian dimulai dari tahun 2006-2009. Hipotesis yang dikemukakan adalah Cash...

  15. ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI KEPUTUSAN KONSUMEN DALAM PEMBELIAN MOBIL TOYOTA YARIS PADA PT. HADJI KALLA MAKASSAR

    OpenAIRE

    DWIPERKASA S, GALIH

    2007-01-01

    Penelitian ini bertujuan untuk menganalisis faktor-faktor yang mempengaruhi keputusan konsumen dalam pembelian mobil toyota yaris pada PT. Hadji kalla makassar. Metode analisis yang digunakan dalam penelitian ini adalah analisis regresi linear berganda dengan program SPSS Versi 18. Populasi yang digunakan adalah masyarakat Makassar yang telah membeli mobil Toyota Yaris PT. Hadji Kalla Makassar, sedangkan sampel yang digunakan sebanyak 100 orang dengan metode purposive sampling. Temuan penelit...

  16. Change of Paradigm for the Reversed Field Pinch

    International Nuclear Information System (INIS)

    The reversed field pinch (RFP) is a magnetic configuration germane to the tokamak, but it produces most of its magnetic field by the currents flowing inside the plasma; external coils provide only a small edge toroidal field whose sign is reversed with respect to the central one, whence the name of the configuration. Because of the presence of magnetic turbulence and chaos, the RFP had been considered for a long period as a terrible confinement configuration. However, recently a change of paradigm occurred for this device. Indeed, when the toroidal current is increased in the RFX-mod RFP in Padua (Italy), a self-organized helical state with an internal transport barrier (ITB) develops, and a broad zone of the plasma becomes hot (above 1 keV for a magnetic field above 0.8 T). The present theoretical picture of the RFP mainly comes from three-dimensional nonlinear visco-resistive MHD simulations whose dynamics has strong similarities with the experimental one, and triggered the experimental search for RFP states with improved confinement. The RFP ohmic state involves a helical electrostatic potential generating, as an electric drift, the so-called dynamo velocity field. The magnetic topology can bifurcate from a magnetic island to kink-like magnetic surfaces with higher resilience to magnetic chaos. This theoretical scenario was found to be relevant when ITB's enclosing a broad hot domain were discovered. The ITBs occur in the vicinity of the maximum of the safety factor. The new paradigm for the RFP supports its reappraisal as a low-external field, non-disruptive, ohmically heated approach to magnetic fusion, exploiting both self-organization and technological simplicity. Furthermore the RFP has the same Greenwald density limit as the tokamak, and it is an excellent test bed for the efficient control of multiple resistive wall modes. Its helical magnetic structure makes it germane to the stellarator too. As a result the RFP is also useful to bring support to the

  17. NEMÁTODOS PARÁSITOS DE Lutjanus synagris (Linneaus, 1758 Y Lutjanus analis> (Cuvier, 1828 (PERCIFORMES, LUTJANIDAE EN LAS ZONAS DE SANTA MARTA Y NEGUANJE, CARIBE COLOMBIANO

    Directory of Open Access Journals (Sweden)

    Cortés J.

    2009-09-01

    Full Text Available Se describen los nemátodos encontrados en el sistema digestivo de las especies de pargo Lutjanus synagris y Lutjanus analis>. Esta investigación se orientó principalmente a la clasificación taxonómica de los parásitos y no a los efectos o patologías que estos puedan ocasionar en los peces. Se tuvo en cuenta que en Colombia los pargos constituyen uno de los recursos de mayor importancia para la comercialización; Lutjanus synagris y Lutjanus analis> son especies demersales explotadas a lo largo de toda la región costera e insular del Caribe colombiano. Los tractos digestivos se colectaron de los pargos capturados artesanalmente (nasa, cordel por pescadores de las zonas de Santa Marta y Neguanje; se identificaron los siguientes géneros de nemátodos: Capillaria spp., Contracaecum spp., Cucullanus spp. y Raphidascaris spp.; el último género fue el más representativo.

  18. La tecnología como herramienta de empoderamiento para el colectivo de mujeres mayores

    OpenAIRE

    Del Prete, Annachiara

    2010-01-01

    La presente tesis se enmarca dentro del proyecto europeo Equal Igualdader 2005-2005, (AD 1002) El objetivo principal de esta investigación es lo de Capacitar a las mujeres mayores de la Comarca del Montsià en el uso de las TICs, como herramienta de empoderamiento en relación a la percepción de si mismas y para la recuperación de su memoria histórica.El resultado de un primer analisi estadisticos sobre la condiciones de las mujeres de la comarca del Montsiá, ha puesto de relieve la necesidad d...

  19. Los Alamos compact toroid, fast-liner, and high-density Z-pinch programs

    Energy Technology Data Exchange (ETDEWEB)

    Linford, R.K.; Sherwood, A.R.; Hammel, J.E.

    1981-03-01

    The Compact Toroid (CT) and High Density Z-Pinch (HDZP) are two of the plasma configurations presently being studied at Los Alamos. The purpose of these two programs, plus the recently terminated (May 1979) Fast Liner (FL) program, is summarized in this section along with a brief description of the experimental facilities. The remaining sections summarize the recent results and the experimental status.

  20. Magnetic Rayleigh-Taylor instability mitigation in large-diameter gas puff Z-pinch implosions

    International Nuclear Information System (INIS)

    Recently, a new approach for efficiently generating K-shell x-rays in large-diameter, long-implosion time, structured argon gas Z-pinches has been demonstrated based on a 'pusher-stabilizer-radiator' model. In this paper, direct observations of the Rayleigh-Taylor instability mitigation of a 12-cm diameter, 200-ns implosion time argon Z-pinch using a laser shearing interferometer (LSI) and a laser wavefront analyzer (LWA) are presented. Using a zero-dimensional snowplow model, the imploding plasma trajectories are calculated with the driver current waveforms and the initial mass distributions measured using the planar laser induced fluorescence method. From the LSI and LWA images, the plasma density and trajectory during the implosion are measured. The measured trajectory agrees with the snowplow calculations. The suppression of hydromagnetic instabilities in the ''pusher-stabilizer-radiator'' structured loads, leading to a high-compression ratio, high-yield Z-pinch, is discussed. For comparison, the LSI and LWA images of an alternative load (without stabilizer) show the evolution of a highly unstable Z-pinch