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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. 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)

    1998-12-31

    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.

  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. 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)

    1996-12-31

    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.

  5. Pinched Nerve

    Science.gov (United States)

    ... You are here Home » Disorders » All Disorders Pinched Nerve Information Page Pinched Nerve Information Page What research is being done? Within the NINDS research programs, pinched nerves are addressed primarily through studies associated with pain ...

  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. Development of an analytic outline for the aflatoxins analysis in grains and flours; Desarrollo de un esquema analitico para el analisis de aflatoxinas en granos y harinas

    Energy Technology Data Exchange (ETDEWEB)

    Sibaja Adams, Roxana

    2000-07-01

    The instrumental and analytic conditions were optimized for the aflatoxine determination B1, B2, 1 and G2 in corn and peanut byl iquid chromatography of high discharge following the analyzing method AOAC 994,08. Besides, it was defined a function for evaluating the dependence of the chromatographic discharge with the aflatoxine concentration. The analyzing method was validated, and four calibration curves were obtained for the aflatoxine B1, B2, G1 and G2, which turned to have a heterocedastico behavior. The applicability of this method was demonstrated, obtaining imagines of appropriate merit and comparable with those reported by the AOAC. Additionally, the applicability of the chromatographic method was demonstrated in fine layer for the presumptive analysis of aflatoxine, allowing both methods to propose an outline of reliable analysis of real samples. [Spanish] Se optimizaron las condiciones instrumentales y analiticas para la determinacion de aflatoxinas B1, B2, G1 y G2 en maiz y mani por Cromatografia liquida de alto desempeno siguiendo el metodo de analisis AOAC 994,08. Ademas, se definio una funcion para evaluar la dependencia del desempeno cromatografico con la concentracion de aflatoxinas.Se valido el metodo de analisis y se obtuvieron las cuatro curvas de calibracion para las aflatoxinas B1, B2, G1 y G2, las que resultaron tener un comportamiento heterocedastico. Se demostro la aplicabilidad del metodo, obteniendose figuras de merito adecuadas y comparables con las reportadas por el AOAC.Adicionalmente, se demostro la aplicabilidad del metodo de cromatografia en capa fina para el analisis presuntivo de aflatoxinas, permitiendo ambos metodos proponer un esquema de analisis confiable de muestras reales.

  8. 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.

  9. ANALISIS PRELIMINARES DE UN FELDESPATO PARA SU CERTIFICACIÓN COMO MATERIAL DE REFERENCIA

    OpenAIRE

    Lizeth Mendoza Sánchez; Edith Zapata Campos; Florianne Castillo Borja

    2010-01-01

    En este trabajo se presentan los análisis cualitativos y semi-cuantitativos aplicados a un feldespato candidato a MRC (material certificado de referencia) para la industria del vidrio. Los elementos que se encontraron por medio de FRX (espectrometría de fluorescencia de rayos X) en el feldespato son Mg, Na, Fe, K, Ti, Zr, Al y Si. El análisis cualitativo por medio de difracción de rayos X demostró que el 81.6% del material analizado correspondía a un feldespato compuesto por sodio y potasio p...

  10. 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.

  11. ANALISIS PRELIMINARES DE UN FELDESPATO PARA SU CERTIFICACIÓN COMO MATERIAL DE REFERENCIA

    Directory of Open Access Journals (Sweden)

    Lizeth Mendoza Sánchez

    2010-01-01

    Full Text Available En este trabajo se presentan los análisis cualitativos y semi-cuantitativos aplicados a un feldespato candidato a MRC (material certificado de referencia para la industria del vidrio. Los elementos que se encontraron por medio de FRX (espectrometría de fluorescencia de rayos X en el feldespato son Mg, Na, Fe, K, Ti, Zr, Al y Si. El análisis cualitativo por medio de difracción de rayos X demostró que el 81.6% del material analizado correspondía a un feldespato compuesto por sodio y potasio principalmente. Los análisis de homogeneidad física y química mostraron que el material era homogéneo con un tamaño de partícula no mayor a 63 μm y que todos los elementos de interés son homogéneos en muestras de 4 g.

  12. 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.

  13. Sistemas de control de gestion, analisis para organizaciones sin fines de lucro

    Directory of Open Access Journals (Sweden)

    Juan Ricardo Saldías Cerda

    2006-07-01

    Full Text Available En la presente investigación se revisarán distintos modelos de control de gestión y como estos han evolucionado desde los basados exclusivamente en la contabilidad, hasta hoy en día, en que la incorporación de conceptos como capital humano y Stakeholder son considerados como elementos claves. Modelos que también han sido considerado por las instituciones sin fines de lucro, como son las organizaciones  públicas en su implantación de la estrategia. Junto a la revisión de los antecedentes bibliográficos, se procedió a realizar algunas comparaciones de modelos encontrados, en  particular se utilizó el Cuadro de Mando Integral (CMI como referencia, en sus distintos estados evolutivos, el cual ha incorporado cada vez con mayor énfasis el concepto de capital humano en su enfoque. Además, se consideró el concepto de Stakeholder, planteado por algunos autores como una variable imprescindible en el planteamiento estratégico y posterior desarrollo del modelo de gestión. Lo anterior permitió definir el marco referencial, para plantear un modelo que pudiese ser aplicado en organizaciones sin fines de lucro, como lo es un hospital público. En donde se deben tener presente las diferentes restricciones estructurales y culturales que afectan o interfieren en la aplicación de cualquier modelo o estrategia, representados y descritos en los Satkeholder. Next to the revision of the bibliographical antecedents, proceeded to carry out some comparisons of models found, particularly the Balance Scorecard was utilized (BSC as reference, in its different evolutionary states, which has incorporated each time with greater emphasis the concept of human capital in its focus. Besides, the concept was considered of Stakeholder, presented by some authors as an indispensable variable in the approach strategic and subsequent development of the model of management. The previous thing permitted to define the framework referential, to present a model that could

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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)

    1999-12-31

    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.

  19. 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

  20. Introduction to Pinch Technology

    DEFF Research Database (Denmark)

    Rokni, Masoud

    ? 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 introduced...

  1. Helical-D pinch

    International Nuclear Information System (INIS)

    Schaffer, M.J.

    1997-08-01

    A stabilized pinch configuration is described, consisting of a D-shaped plasma cross section wrapped tightly around a guiding axis. The open-quotes helical-Dclose quotes geometry produces a very large axial (toroidal) transform of magnetic line direction that reverses the pitch of the magnetic lines without the need of azimuthal (poloidal) plasma current. Thus, there is no need of a open-quotes dynamoclose quotes process and its associated fluctuations. The resulting configuration has the high magnetic shear and pitch reversal of the reversed field pinch (RFP). (Pitch = P = qR, where R = major radius). A helical-D pinch might demonstrate good confinement at q << 1

  2. Z-pinches

    International Nuclear Information System (INIS)

    Yan'kov, V.V.

    1991-01-01

    Although pinches, unlike tokamaks, have not occupied a central position in fusion research, their structural simplicity and the wealth of physical processes associated with plasma foci have maintained a steady interest. The development of Z-pinches, including plasma foci, micropinches, and dense Z-pinches, is reviewed. Attention is focused on theoretical as opposed to experimental questions, and on recent work rather than the basic results now found in textbooks. Finally, Soviet work is discussed more fully than work done abroad, and applications to controlled fusion are emphasized

  3. 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.

  4. CÁLCULO E INTERPRETACIÓN DE LAS TRAYECTORIAS DE PUNTOS DE COMPOSICIÓN CONSTANTE (PINCH EN COLUMNAS SIMPLES DE DESTILACIÓN PARA MEZCLAS AZEOTRÓPICAS HOMOGÉNEAS CÁLCULO E INTERPRETAÇÃO DAS TRAJETÓRIAS DE PONTOS DE COMPOSIÇÃO CONSTANTE (PINCH EM COLUNAS SIMPLES DE DESTILAÇÃO PARA MISTURAS AZEOTRÓPICAS HOMOGÊNEAS CALCULATION AND INTERPRETATION OF THE PINCH POINTS TRAJECTORIES IN SIMPLE DISTILLATION COLUMNS FOR HOMOGENEOUS AZEOTROPIC MIXTURES

    Directory of Open Access Journals (Sweden)

    César Augusto Sánchez

    2011-12-01

    Full Text Available Se presenta un método de continuación del tipo predictor-corrector para trazar completamente los ramales de puntos de pinch asociados con los productos o seudoproductos de una columna de destilación azeotrópica homogénea. El método trata fácilmente con los puntos de retorno permitiendo la localización de los puntos pinch del tipo tangente. El concepto se fundamenta en las ideas de Fidkowski, Malone y Doherty, pero incluye algunas novedades, como la estrategia de iniciación de los cálculos, la forma de obtener el vector tangente y el grupo de ecuaciones sobre el cual se aplica la técnica. Se ilustran tres ejemplos con las soluciones de acetona + cloroformo + benceno, acetona + cloroformo + metanol y ácido acético + amilalcohol + amilacetato, enfatizando en casos que muestran mejores posibilidades de separación en la condición de reflujo finito que en la operación con reflujo total.Apresenta-se um método de continuação do tipo preditor-corretor para traçar completamente os ramos de pontos de pinch associados com os produtos ou pseudoprodutos de uma coluna de destilação azeotrópica homogénea. O método trata facilmente com os pontos de retorno permitindo a localização dos pontos pinch do tipo tangente. O conceito fundamenta-se nas ideias de Fidkowski, Malone e Doherty, mas inclui algumas novidades, como a estratégia de iniciação dos cálculos, a forma de obter o vetor tangente e o grupo de equações sobre o qual se aplica a técnica. Ilustram-se três exemplos com as soluções de acetona + clorofórmio + benzeno, acetona + clorofórmio + metanol e ácido acético + amilálcool+ amilacetato, enfatizando em casos que mostram melhores possibilidades de separação na condição de refluxo finito que na operação com refluxo total.A continuation method of the kind predictor-corrector is presented for completely tracking of the pinch points branches related to the products or pseudoproducts of a homogeneous azeotropic

  5. Z-pinches

    International Nuclear Information System (INIS)

    Yan'kov, V.V.

    1991-01-01

    The development of Z-pinches, including plasma foci, micropinches and dense Z-pinches are reviewed. A special attention is paid to the physics of sausage instability development. Theoretical questions are discussed in more detail that the experimental ones, recent works - to a fuller extent than the fundamental pioneer ones which are included in the textbooks. The Soviet works are given a greater coverage as compared to the foreign ones. An emphasis is made on the problem of controlled thermonuclear fusion

  6. Development of a computer system for the thermodynamic analysis; Desarrollo de un sistema de computo para el analisis termodinamico

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez R, Aurelio; Romero S, Antonio; Gomez G, Herminia [Instituto Politecnico Nacional, Mexico, D.F. (Mexico)

    1996-02-01

    The objective of this paper is to explain the programs that are contained in a Thermodynamic Computer System. Students can use this Computer System to make complicated calculations that are required in Thermodynamic Analysis. One of this programs is used to obtain the expression of heat capacity of pure substances in terms of temperature, at constant pressure. A database of pure substances has been created which retrieves the thermodynamic properties (enthalpy, entropy and Gibbs free energy) in such a format that it is very easy to understand. The changes of state functions for chemical reactions can also be calculated. Another program is used to estimate the equilibrium conditions in multicomponent and multiphase systems. [Spanish] En el presente trabajo se muestran los programas de computo que conforman un Sistema de Analisis Termodinamico desarrollado con el fin de facilitar los calculos y la comprension de algunos principios de la Termodinamica. Este sistema permite obtener la funcionalidad de la capacidad calorifica con la temperatura de sustancias puras, a presion constante; obtener de manera rapida y concisa las propiedades termodinamicas (entalpia, entropia y energia libre de Gibbs) de elementos y compuestos puros almacenados en una base de datos; determinar los cambios en las funciones de estado de reacciones quimicas entre sustancias puras; determinar el equilibrio en sistemas multicomponentes y multifasicos. Se indican los alcances de este grupo de programas de computo asi como su aplicacion a procesos practicos.

  7. 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

  8. 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.

  9. 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.

  10. Dense Z-pinch plasmas

    International Nuclear Information System (INIS)

    Shlachter, J.S.; Hammel, J.E.; Scudder, D.W.

    1985-01-01

    Early researchers recogniZed the desirable features of the linear Z-pinch configuration as a magnetic fusion scheme. In particular, a Z-pinch reactor might not require auxiliary heating or external field coils, and could constitute an uncomplicated, high plasma β geometry. The simple Z pinch, however, exhibited gross MHD instabilities that disrupted the plasma, and the linear Z pinch was abandoned in favor of more stable configurations. Recent advances in pulsed-power technology and an appreciation of the dynamic behavior of an ohmically heated Z pinch have led to a reexamination of the Z pinch as a workable fusion concept

  11. Dense sheet Z-pinches

    International Nuclear Information System (INIS)

    Tetsu, Miyamoto

    1999-01-01

    The steady state and quasi-steady processes of infinite- and finite-width sheet z-pinches are studied. The relations corresponding to the Bennett relation and Pease-Braginskii current of cylindrical fiber z-pinches depend on a geometrical factor in the sheet z-pinches. The finite-width sheet z-pinch is approximated by a segment of infinite-width sheet z-pinch, if it is wide enough, and corresponds to a number of (width/thickness) times fiber z-pinch plasmas of the diameter that equals the sheet thickness. If the sheet current equals this number times the fiber current, the plasma created in the sheet z-pinches is as dense as in the fiber z-pinches. The total energy of plasma and magnetic field per unit mass is approximately equal in both pinches. Quasi-static transient processes are different in several aspects from the fiber z-pinch. No radiation collapse occurs in the sheet z-pinch. The stability is improved in the sheet z-pinches. The fusion criterions and the experimental arrangements to produce the sheet z-pinches are also discussed. (author)

  12. 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)

    1993-12-31

    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.

  13. 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.

  14. 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

  15. The static pinch

    Energy Technology Data Exchange (ETDEWEB)

    Longmire, Conrad L [University of California, Los Alamos Scientific Laboratory, Los Alamos, NM (United States)

    1958-07-01

    In a pinch, the outward diffusion of plasma due to collisions can be balanced by the inward drift resulting from ExB, where E is the applied electric field and B the magnetic field. From the equation expressing the balance of these two effects, together with the pressure balance equation, one obtains the perpendicular conductivity, which is about one-half of the classical parallel conductivity. This result has been applied to the problem of a static pinch under the assumptions: 1) there is an applied longitudinal (B{sub z}) magnetic field; 2) the plasma is isothermal; 3) the solution depends only on the radial coordinate.

  16. 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...

  17. Un enfoque de analisis multiobjetivo para la planeación agregada de producción

    Directory of Open Access Journals (Sweden)

    Ricardo Smith Quintero

    2004-01-01

    Full Text Available La finalidad del presente articulo, es difundir las bondades del análisis multiobjetivo como herramienta de vital importancia dentro de las nuevas tendencias de los procesos de toma de decisiones. En concreto, en la planeación agregada de la producción. Para esto, gerencialmente se ha aceptado a la calidad, el tiempo y el costo como los tres objetivos fundamentales de dicho plan. Esto nos lleva a pensar que dentro del proceso de toma de decisiones que debe llevar a cabo un administrador de producción para realizar una correcta asignación de los recursos, existen múltiples sub objetivos empresariales derivados de los tres anteriores, los cuales deben ser cumplidos para alcanzar la meta corporativa. El artículo se basa principalmente en la creación de un modelo de planeación agregada bajo análisis multiobjetivo, sustentado en la teoría de la toma de decisiones contemporánea, y un problema de aplicación usando dicho modelo.

  18. 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

  19. Stage theta pinch experiments

    International Nuclear Information System (INIS)

    Linford, R.K.; Downing, J.N.; Gribble, R.F.; Jacobson, A.R.; Platts, D.A.; Thomas, K.S.

    1975-01-01

    The Staged Theta Pinch program is designed to study the technological and physics problems associated with producing fat plasmas and separating the implosion heating from the adiabatic compression. Several methods of implosion heating are discussed. Circuit diagrams and theoretical magnetic field behavior are described for the STP and resonant heating experiments. (MOW)

  20. Un enfoque de analisis multiobjetivo para la planeación agregada de producción

    OpenAIRE

    Ricardo Smith Quintero; Alexander Correa Espinal; Jaime Alberto Aristizábal

    2004-01-01

    La finalidad del presente articulo, es difundir las bondades del análisis multiobjetivo como herramienta de vital importancia dentro de las nuevas tendencias de los procesos de toma de decisiones. En concreto, en la planeación agregada de la producción. Para esto, gerencialmente se ha aceptado a la calidad, el tiempo y el costo como los tres objetivos fundamentales de dicho plan. Esto nos lleva a pensar que dentro del proceso de toma de decisiones que debe llevar a cabo un adminis...

  1. Analisis para la creación, organización y desarrollo de la biblioteca digital de Colombia

    OpenAIRE

    Arias Ordoñez, José de Jesús

    2008-01-01

    Resumen: Partiendo de una reflexión epistemológica se dilucida conceptualmente la biblioteca digital y se proyecta un modelo de carácter nacional. Se toman en consideración, y se estudian, los proyectos más relevantes que dieron origen a las bibliotecas digitales en USA y Europa, al igual que las investigaciones y los desarrollos alcanzados por la Federación Internacional de Bibliotecas Digitales. A partir de estos estudios, se hace un examen sobre las potencialidades de Colombia para soporta...

  2. Analisis de la Función Reflexiva-RF en Sesiones de Grupo de Terapia Focalizada para Adolescentes Violentos

    Directory of Open Access Journals (Sweden)

    Glenda Cryan

    2016-01-01

    Full Text Available En este artículo se realizó el análisis de la Función Reflexiva o mentalización en la segunda y octava sesión de un dispositivo específico de corto plazo y orientación psicodinámica desarrollado para el abordaje terapéutico de la violencia juvenil al que denominamos Grupo de Terapia Focalizada- GTF. Los resultados indican que los adolescentes violentos presentan un bajo nivel de mentalización, el cual se vio reflejado en la oscilación entre el rechazo y la evasión de las intervenciones terapéuticas vinculadas a los estados mentales y las explicaciones de desconocimiento o de recuerdos distorsionados hacia los mismos. Si bien no fue posible desarrollar una mayor actividad reflexiva o capacidad de mentalización en esta instancia del tratamiento, el análisis de proceso permitió observar que en la octava sesión del dispositivo GTF hubo un mayor porcentaje de segmentos en los que no se rechazó la posibilidad de reflexionar en comparación con la segunda sesión.

  3. Staged theta pinch experiments

    International Nuclear Information System (INIS)

    Linford, R.K.; Downing, J.N.; Gribble, R.F.; Jacobson, A.R.; Platts, D.A.; Thomas, K.S.

    1976-01-01

    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.)

  4. Sheet pinch devices

    International Nuclear Information System (INIS)

    Anderson, O.A.; Baker, W.R.; Ise, J. Jr.; Kunkel, W.B.; Pyle, R.V.; Stone, J.M.

    1958-01-01

    Three types of sheet-like discharges are being studied at Berkeley. The first of these, which has been given the name 'Triax', consists of a cylindrical plasma sleeve contained between two coaxial conducting cylinders A theoretical analysis of the stability of the cylindrical sheet plasma predicts the existence of a 'sausage-mode' instability which is, however, expected to grow more slowly than in the case of the unstabilized linear pinch (by the ratio of the radial dimensions). The second pinch device employs a disk shaped discharge with radial current guided between flat metal plates, this configuration being identical to that of the flat hydromagnetic capacitor without external magnetic field. A significant feature of these configurations is the absence of a plasma edge, i.e., there are no regions of sharply curved magnetic field lines anywhere in these discharges. The importance of this fact for stability is not yet fully investigated theoretically. As a third configuration a rectangular, flat pinch tube has been constructed, and the behaviour of a flat plasma sheet with edges is being studied experimentally

  5. Fusion with Z-pinches

    International Nuclear Information System (INIS)

    Cook, D.

    1998-06-01

    In the past thirty-six months, great progress has been made in x-ray production using high-current z-pinches. Today, the x-ray energy and power output of the Z accelerator (formerly PBFA-II) is the largest available in the laboratory. These z-pinch x-ray sources have the potential to drive high-yield ICF reactions at affordable cost if several challenging technical problems can be overcome. In this paper, the recent technical progress with Z-pinches will be described, and a technical strategy for achieving high-yield ICF with z-pinches will be presented

  6. 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.

  7. Communication system and spectral analysis for Ge-Li and GeHp detectors; Sistema de comunicaciones y analisis de espectros para detectores Ge-Li y GeHp

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J; Castano, P; Bonino, A D; Righetti, M A

    1991-12-31

    An integral communication and spectral analysis system (SICADE) was developed and implemented to satisfy the need to optimize and automate the measurement system used in Atucha I nuclear power plant for the activity in the primary loop`s water extracted by the TV system. The importance of these measurements is based on the fact that from the spectrometric analysis of the samples extracted, the Iodines-GN and Iodines-Iodines relations, which allow to detect the presence of deficient fuel elements, are calculated. The system developed is based on two modules integrated in a unique set commanded by the operators through the screen dialogue. (Author). [Espanol] Dada la necesidad de optimizar y automatizar el sistema de medicion utilizado en la Central Nuclear Atucha I para la actividad en el agua del circuito primario extraida a traves del sistema TV se desarrollo e implemento un sistema integral de Comunicacion y Analisis de espectros (SICADE). La importancia de estas mediciones radica en el hecho que del analisis espectrometrico de las muestras extraidas se calculan las relaciones entre Iodos-GN e Iodos-Iodos que permiten detectar la presencia de elementos combustibles fallados. El sistema desarrollado esta basado en dos modulos integrados en un unico conjunto comandado por el operador a traves del dialogo por pantalla. (Autor).

  8. 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

  9. 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

  10. Risk analysis; Analisis de riesgos

    Energy Technology Data Exchange (ETDEWEB)

    Baron, J H; Nunez McLeod, J; Rivera, S S [Universidad Nacional de Cuyo, Mendoza (Argentina). Instituto de Capacitacion Especial y Desarrollo de Ingenieria Asistida por Computadora (CEDIAC)

    1997-07-01

    This book contains a selection of research works performed in the CEDIAC Institute (Cuyo National University) in the area of Risk Analysis, with specific orientations to the subjects of uncertainty and sensitivity studies, software reliability, severe accident modeling, etc. This volume presents important material for all those researches who want to have an insight in the risk analysis field, as a tool to solution several problems frequently found in the engineering and applied sciences field, as well as for the academic teachers who want to keep up to date, including the new developments and improvements continuously arising in this field. [Spanish] Este libro contiene una seleccion de trabajos de investigacion realizados dentro del Instituto de Capacitacion Especial y Desarrollo de la Ingenieria Asistida por Computadora en el area del analisis de riesgos, con una orientacion hacia el estudio de incertidumbres y sensibilidad, confiabilidad de software, modelacion de accidentes severos, etc. Este volumen recoge un material de indudable importancia e interes para todos aquellos investigadores y profesionales que desean incursionar en este campo del analisis de riesgos como herramienta para la solucion de problemas frecuentemente encontrados en la ingenieria y las ciencias aplicadas, asi como para los academicos que desean mantenerse al dia, conociendo los nuevos desarrollos y tecnicas que constantemente aparecen en su area.

  11. 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

  12. 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)

    1998-12-31

    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

  13. 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.

  14. Development of an effective pinch bar

    CSIR Research Space (South Africa)

    Ottermann, RW

    2003-02-01

    Full Text Available . ....................................10 Figure 3-3: Layout of lightweight pinch bar extruded fibreglass tube. ..................................11 Figure 3-4: XDM lightweight pinch bar with manufactured glass fibre bar. ..........................12 Figure 3-5: XDM lightweight pinch... bar with extruded glass fibre tube. ................................12 Figure 3-6: Stiffness of a 2.8m lightweight pinch bar with an extruded glass fibre tube and a 25mm steel pinch bar...

  15. Reversed field pinch diagnostics

    International Nuclear Information System (INIS)

    Weber, P.G.

    1986-01-01

    The Reversed Field Pinch (RFP) is a toroidal, axisymmetric magnetic confinement configuration characterized by a magnetic field configuration in which the toroidal magnetic field is of similar strength to the poloidal field, and is reversed at the edge compared to the center. The RFP routinely operates at high beta, and is a strong candidate for a compact fusion device. Relevant attributes of the configuration will be presented, together with an overview of present and planned experiments and their diagnostics. RFP diagnostics are in many ways similar to those of other magnetic confinement devices (such as tokamaks); these lectures will point out pertinent differences, and will present some diagnostics which provide special insights into unique attributes of the RFP

  16. 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

  17. Putting the pinch on reactors

    International Nuclear Information System (INIS)

    Glavic, P.; Kravanja, Z.; Homsak, M.

    1990-01-01

    Pinch technology has proven to be a powerful tool for designing new processes and retrofitting old ones. But, until recently, it was thought to pertain only to heat exchanger networks, separators and power devices (such as heat engines and heat pumps). Regarded as process background, reactors have been left out of heat integrations. Their structure, however, can be changed and, within limits, their parameters modified to better exploit energy. In a pinch-designed plant, heat is transferred between the hot and cold process streams so efficiently that the plant's utility requirements (heat sources and sinks) are minimal. The design procedure is discussed. It involves two steps: finding a nearly optimal process structure by means of an analysis of process-temperature-vs.- enthalpy diagrams, and then optimizing the structure by means of grid diagrams or a computerized procedure

  18. Eigenvalue pinching on spinc manifolds

    Science.gov (United States)

    Roos, Saskia

    2017-02-01

    We derive various pinching results for small Dirac eigenvalues using the classification of spinc and spin manifolds admitting nontrivial Killing spinors. For this, we introduce a notion of convergence for spinc manifolds which involves a general study on convergence of Riemannian manifolds with a principal S1-bundle. We also analyze the relation between the regularity of the Riemannian metric and the regularity of the curvature of the associated principal S1-bundle on spinc manifolds with Killing spinors.

  19. 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.

  20. Z-Pinch Fusion for Energy Applications

    International Nuclear Information System (INIS)

    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

  1. 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.

  2. 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

  3. Analisis tecnico, socioeconomico y ambiental de la electrificación con energía solar fotovoltaica aislada para vivienda rural en Hato Corozal, Casanare, Colombia

    OpenAIRE

    Edwin Blasnilo Rúa Ramírez; Andrea Isabel Barrera Siabato; Martín Gómez Orduz

    2017-01-01

    La electrificación con energía solar fotovoltaica aislada es la opción más viable para vivienda rural, en especial si se encuentra muy distante del sistema nacional interconectado. Hato Corozal, Casanare, Colombia, es un municipio estructurado en su área rural por fincas muy alejadas entre sí. Su mayor inconveniente de desarrollo social y económico es la falta de electricidad como servicio de primera necesidad.  La gobernación de Casanare a través del fondo nacional de regalías aprobó la inst...

  4. ESPECTROS DE CARGA DE CAMIONES PARA EL ANALISIS Y DISEÑO DE PAVIMENTOS EN LA REGIÓN ANDINA COLOMBIANA

    Directory of Open Access Journals (Sweden)

    Luis Macea

    2015-01-01

    Full Text Available Para el adecuado dimensionamiento de las estructuras de pavimento, se requiere la estimación de los efectos agrupados de las cargas del tránsito, por lo cual se debe conocer el número y tipo de vehículos que circularán por la vía, así como la intensidad del peso y la configuración del eje que la aplica, aspecto que es abordado cuando se hace la caracterización del tránsito a través de espectros de carga. En razón de esto en el presente artículo se construyen espectros de la capacidad por tipo de eje de camiones para diferentes rutas y departamentos de la región andina colombiana, de igual forma se Identifican los porcentajes de sobrecarga y las zonas donde se sobrepasa el límite máximo de peso permitido, así como los tipos de productos transportados en condiciones de exceso de peso. Para esto, se realizaron veintiséis (26 operativos de pesaje móvil de camiones en distintos corredores de carga de la región andina en el año 2013, con lo cual se obtuvo una muestra de 94.132 ejes pesados, a partir de los cuales se agruparon las capacidades por cada tipo de eje y se determinaron sus respectivas frecuencias de arrumaje. Los resultados encontrados indicaron que el eje sencillo direccional de llanta sencilla presenta un solo pico máximo con cierto grado de asimetría, el cual se encuentra regularmente por debajo de la carga máxima legal establecida para este tipo de eje, Por otro lado, los ejes sencillo de llanta doble presentan una bimodalidad con dos picos máximos muy parejos, uno en el sentido de las cargas bajas y el otro en el sentido de las cargas altas, mientras que los ejes tándem y tridem de llanta doble presentan una bimodalidad caracterizada por el predominio de un pico máximo absoluto del lado de las cargas altas lo que indica que los camiones están circulando con carga al límite permitido.

  5. ANALISIS DE LA REMOCIÓN DE CARGAS CONTAMINANTES A TRAVÉS DE UN FILTRO BIOLÓGICO PARA TRATAR EFLUENTESPROVENIENTE DEPROCESOS PRODUCTIVOS AGROPECUARIOS

    OpenAIRE

    Huetio Passos, Jhenny Katherine; Ortiz Sarria, Mauricio Fernando; Granada T., Carlos Arturo

    2016-01-01

    Analizar las cargas contaminantes de un filtro biológico que recibe aguas residuales provenientes de procesos productivos agropecuarios de la granja del Centro Agropecuario del Servicio Nacional de Aprendizaje SENA, en el Municipio de Popayán, Departamento del Cauca.Este trabajo se desarrolló a nivel de campo y laboratorio en donde se utilizó equipo de análisis de agua y equipo de laboratorio. Para la caracterización del efluente se realizaron doce muestreos compuestos durante un el ciclo de ...

  6. 1/4-pinched contact sphere theorem

    DEFF Research Database (Denmark)

    Ge, Jian; Huang, Yang

    2016-01-01

    Given a closed contact 3-manifold with a compatible Riemannian metric, we show that if the sectional curvature is 1/4-pinched, then the contact structure is universally tight. This result improves the Contact Sphere Theorem in [EKM12], where a 4/9-pinching constant was imposed. Some tightness...

  7. 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.

  8. Lower pinch radius limit in EXTRAP

    International Nuclear Information System (INIS)

    Lehnert, B.

    1989-01-01

    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)

  9. Plasma sheath dynamics in pinch discharge

    International Nuclear Information System (INIS)

    Mansour, A.A.Abd-Fattah

    1995-01-01

    The main interest of the study was to understand the dynamic and to determine the plasma parameters in the 3.5 meter θ-pinch discharge. The 3.5 meter thetatron plasma device has been reconstructed and developed which consist of four capacitor banks: a) Main pinch capacitor bank, (θ-pinch bank) consists of 40 capacitors connected in parallel each of 1.5 μ F., with maximum energy equal to 48 k Joule. b) Preionization capacitor bank (z-pinch) consists of capacitors connected in series each of 1.5μ F., with maximum energy to 0.94 k Joule. c) Bias field bank consists of 4 capacitors connected in parallel each of 38μ F., with maximum energy equal to 4.46 k Joule. d) Screw pinch capacitor bank consists of 5 capacitors connected in parallel each of 1.5μ F., with maximum energy equal to 6 k Joule

  10. Solid fiber Z-pinches

    International Nuclear Information System (INIS)

    Lindemuth, I.R.

    1989-01-01

    One- and two-dimensional magnetohydrodynamic computations have been performed to study the behavior of solid deuterium fiber Z-pinch experiments performed at Los Alamos and the Naval Research Laboratory. The computations use a tabulated atomic data base and ''cold-start'' initial conditions. The computations predict that the solid fiber persists longer in existing experiments than previously expected and that the discharge actually consists of a relatively low-density, hot plasma which has been ablated from the fiber. The computations exhibit m = 0 behavior in the hot, exterior plasma prior to complete ablation of the solid fiber. The m = 0 behavior enhances the fiber ablation rate. 10 refs., 5 figs

  11. 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.

  12. 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)

    1998-12-31

    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.

  13. Analisis experimental de la propagacion en redes de area corporal para la banda de ultra wideband. experimental characterization of the propagation in ultra wideband body area networks

    Science.gov (United States)

    Garcia Serna, Ruben Gregorio

    Diferentes dispositivos capaces de obtener informacion sobre parametros fisiologicos, cinematicos o contextuales del cuerpo pueden interconectarse de manera inalambrica dando lugar a las denominadas Redes de Area Corporal Inalambricas (WBAN, Wireless Body Area Networks). De entre las posibles tecnologias para establecer los enlaces, Ultra Wideband (UWB) esta captando cada vez un mayor interes debido a caracteristicas tales como el bajo nivel de potencia de transmision requerido (bajo nivel de exposicion a campos electromagneticos), el alto ancho de banda disponible y la alta resolucion temporal/espacial. El diseno de sistemas centrados en el cuerpo requiere de modelos de canal que describan de manera precisa la propagacion de senales en este tipo de entornos. Esta tesis se plantea con el objetivo de contribuir al estudio experimental de la propagacion en sistemas centrados en el cuerpo operando en la banda UWB. En primer lugar, se presenta un marco introductorio a las redes WBAN, sus elementos constitutivos, bandas de frecuencia, estandarizacion y modelos de canal. Ademas, se introducen los fundamentos de la tecnologia UWB y sus aplicaciones en este area. Seguidamente, se analiza en terminos de las perdidas de propagacion y la dispersion de retardo la propagacion en el canal off-body entre un transmisor fijo y un dispositivo receptor colocado sobre la superficie del cuerpo de un sujeto. Se considera la influencia de diferentes aspectos, tales como el entorno de medidas, la posicion de colocacion de una antena sobre el cuerpo y la postura adoptada por un sujeto. Finalmente, se analiza el canal de propagacion in-body considerando el movimiento relativo entre dos dispositivos causado por efecto de la respiracion. Las condiciones de propagacion en el interior del cuerpo se emulan por medio de un phantom liquido para UWB y la caracterizacion se plantea tanto en frecuencia, en terminos del modelado de la forma y el ensanchamiento del espectro Doppler, como en tiempo, por

  14. 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.

  15. Upper pinch radius limit in EXTRAP

    International Nuclear Information System (INIS)

    Lehnert, B.

    1989-12-01

    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)

  16. Analisis tecnico, socioeconomico y ambiental de la electrificación con energía solar fotovoltaica aislada para vivienda rural en Hato Corozal, Casanare, Colombia

    Directory of Open Access Journals (Sweden)

    Edwin Blasnilo Rúa Ramírez

    2017-06-01

    Full Text Available La electrificación con energía solar fotovoltaica aislada es la opción más viable para vivienda rural, en especial si se encuentra muy distante del sistema nacional interconectado. Hato Corozal, Casanare, Colombia, es un municipio estructurado en su área rural por fincas muy alejadas entre sí. Su mayor inconveniente de desarrollo social y económico es la falta de electricidad como servicio de primera necesidad.  La gobernación de Casanare a través del fondo nacional de regalías aprobó la instalación de 206 sistemas solares fotovoltaicos (SFV a las familias más alejadas y más vulnerables del municipio. El objetivo principal de esta investigación fue realizar una evaluación socio-económica de las familias de la zona rural del municipio, beneficiadas con la instalación de estos sistemas SFV. Además, se realizó un análisis técnico de simulación de la operación del SFV dimensionado con 2 días sin sol y luego 12 días con sol, también se hizo una simulación de la operación del SFV dimensionado con 14 días con sol. Esta investigación se abordó desde el enfoque metodológico descriptivo y de investigación aplicada de campo que incluyó visita a las viviendas, aplicación, análisis de instrumentos y registro fotográfico.  Los resultados presentan gran incidencia desde un enfoque social, económico y ambiental que puede llegar a ser implementado en otras áreas rurales del país como ejemplo de uso de tecnologías limpias en favor del desarrollo rural sostenible.

  17. WASTE REDUCTION IN CARMINIC ACID PRODUCTION BY APPLYING PINCH TECHNOLOGY

    OpenAIRE

    Erazo E., Raymundo; Cárdenas R., Jorge L.; Woolcott H., Juan C.

    2014-01-01

    An integrated approach to the design and analisis of heat exchanger networrks (HEN) Is outlined. A case study is used, carminic acid,, to illustrate this integrated approach, to emphasize the economy of 60% energy with respect to convectional process. Se esbozó un análisis de integración de energía por aproximación para el diseño y análisis de una red de transferencia de calor (HEN). Se utilizó un caso estudio, ácido carmínico, para ilustrar esta vía de integración por aproximación y resal...

  18. History of the Z-pinch

    International Nuclear Information System (INIS)

    Lovberg, R.H.

    1988-01-01

    The plasma Z-Pinch occupies a unique position in the history of controlled fusion research as the first confinement and heating scheme to be tried experimentally. In contrast to the sophistication of programs being conducted today, in which extensive theoretical and experimental forces are in close collaboration, early pinch experiments were designed on quite elementary theoretical grounds. Indeed, these systems and the results from them provided the focus for much of the rapid development of theoretical plasma physics and magnetohydrodynamics during the 1950's. In comparison to present programs, these early experiments had the considerable advantage of small size and minimal managerial encumbrance. After nearly three decades of abandonment because of difficulties with MHD instabilities, the Z-pinch is arising once again in a new incarnation characterized by microscopic size and time scales, and very high density. Uniquely in the history of the pinch, the new experimental surprises seem encouraging, rather than discouraging, to the goal of thermonuclear fusion

  19. 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.

  20. The physics of fast Z pinches

    International Nuclear Information System (INIS)

    Ryutov, D.D.; Derzon, M.S.; Matzen, M.K.

    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

  1. Plasma and current structures in dynamical pinches

    International Nuclear Information System (INIS)

    Butov, I.Ya.; Matveev, Yu.V.

    1981-01-01

    Dynamics of plasma layers and current structure in aZ-pinch device has been experimentally investigated. It is found that shaping of a main current envelope is ended with its explosion-like expansion, the pinch decaying after compression to separated current filaments. It is also shown that filling of a region outside the pinch with plasma and currents alternating in directions occurs owing to interaction of current loops (inductions) formed in a magnetic piston during its compression with reflected shock wave. Current circulating in the loops sometimes exceeds 1.5-2 times the current of discharge circuit. The phenomena noted appear during development of superheat instability and can be realized, for example, in theta-pinches, plasma focuses, tokamaks. The experiments were carried out at the Dynamic Zeta-pinch device at an energy reserse of up to 15 kJ (V 0 =24 kV) in a capacitor bank. Half-period of the discharge current is 9 μs; Isub(max)=3.5x10sup(5) A. Back current guide surrounding a china chamber of 28 cm diameter and 50 cm length is made in the form of a hollow cylinder. Initial chamber vacuum is 10 -6 torr [ru

  2. Plasma focus - dense Z pinch and their applications

    International Nuclear Information System (INIS)

    Ishii, Shozo

    1986-02-01

    ''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)

  3. Reversed field pinch ignition requirements

    International Nuclear Information System (INIS)

    Werley, K.A.

    1991-01-01

    Plasma models are described and used to calculated numerically the transport confinement (nτ E ) requirements and steady state operation points for both the reversed field pinch (RFP) and the tokamak. The models are used to examine the CIT tokamak ignition conditions and the RFP experimental and ignition conditions. Physics differences between RFPs and tokamaks and their consequences for a D-T ignition machine are discussed. Compared with a tokamak, the ignition RFP has many physics advantages, including Ohmic heating to ignition (no need for auxiliary heating systems), higher beta, lower ignition current, less sensitivity of ignition requirements to impurity effects, no hard disruptions (associated with beta or density limits) and successful operation with high radiation fractions (f RAD ∼ 0.95). These physics advantages, coupled with important engineering advantages associated with lower external magnetic field, larger aspect ratios and smaller plasma cross-sections, translate to significant cost reductions for both ignition and reactor applications. The primary drawback of the RFP is the uncertainty that the present scaling will extrapolate to reactor regimes. Devices that are under construction should go a long way toward resolving this scaling uncertainty. The 4 MA ZTH is expected to extend the nτ E transport scaling data by three orders of magnitude above the results of ZT-40M, and, if the present scaling holds, ZTH is expected to achieve a D-T equivalent scientific energy breakeven, Q = 1. A base case RFP ignition point is identified with a plasma current of 8.1 MA and no auxiliary heating. (author). 19 refs, 11 figs, 3 tabs

  4. Measurements of high-current electron beams from X pinches and wire array Z pinches

    International Nuclear Information System (INIS)

    Shelkovenko, T. A.; Pikuz, S. A.; Blesener, I. C.; McBride, R. D.; Bell, K. S.; Hammer, D. A.; Agafonov, A. V.; Romanova, V. M.; Mingaleev, A. R.

    2008-01-01

    Some issues concerning high-current electron beam transport from the X pinch cross point to the diagnostic system and measurements of the beam current by Faraday cups are discussed. Results of computer simulation of electron beam propagation from the pinch to the Faraday cup give limits for the measured current for beams having different energy spreads. The beam is partially neutralized as it propagates from the X pinch to a diagnostic system, but within a Faraday cup diagnostic, space charge effects can be very important. Experimental results show evidence of such effects.

  5. ANALISIS PENYEBAB BANJIR KALI JUANA

    Directory of Open Access Journals (Sweden)

    Teguh Marhendi

    2017-04-01

    Full Text Available Kali Juana yang berada di Kabupaten Pati dan Kudus serta sebagian kecil di Kabupaten Grobogan dan Blora, merupakan kawasan banjir. Kejadian banjir di Kali Juana, sudah menjadi rutinitas setiap musim hujan.Dari Januari sampai bulan Mei 2016tercatat terjadi 11 kejadian banjir dibeberapa wilayah, seperti Kecamatan Kaliwungu, Undaan dan Mejobo (Kab. Kudus serta Pati, Margorejo dan Juwana (Kab. Pati. Kali Juana merupakan bifurkasi Kali Serang pada Pintu Wilalung, yang berfungsi sebagai pintu pengatur banjir (dibangun pada zaman Belanda tahun 1918, melalui Kali Babalan menuju ke Kali Juana. Tulisan inidimaksudkan untuk menganalisis penyebab kejadian banjir di Kali Juana. Analisis dilakukan dengan melakukan kajani dan analisis hujan serta mekanisme aliran. Hasil analisis menunjukkan bahwa kondisi Kali Juana dari pertemuan Kali Logung di pintu Wilalung sampai hilir telah mengalami pendangkalan akibat kemiringan dasar atau topografi yang landai, dan mengakibatkan mudah terjadi sedimentasi sehingga mengurangi kapasitas pengaliran. Hal ini menyebabkan luapan banjir sering menggenangi wilayah Kabupaten Kudus dan Pati.

  6. Engineering prototypes for theta-pinch devices

    International Nuclear Information System (INIS)

    Hansborough, L.D.; Hammer, C.F.; Hanks, K.W.; McDonald, T.E.; Nunnally, W.C.

    1975-01-01

    Past, present, and future engineering prototypes for theta-pinch plasma-physics devices at Los Alamos Scientific Laboratory are discussed. Engineering prototypes are designed to test and evaluate all components under system conditions expected on actual plasma-physics experimental devices. The importance of engineering prototype development increases as the size and complexity of the plasma-physics device increases. Past experiences with the Scyllac prototype and the Staged Theta-Pinch prototype are discussed and evaluated. The design of the proposed Staged Scyllac prototype and the Large Staged Scyllac implosion prototype assembly are discussed

  7. 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

  8. Characterization of laser-cut copper foil X-pinches

    Science.gov (United States)

    Collins, G. W.; Valenzuela, J. C.; Hansen, S. B.; Wei, M. S.; Reed, C. T.; Forsman, A. C.; Beg, F. N.

    2016-10-01

    Quantitative data analyses of laser-cut Cu foil X-pinch experiments on the 150 ns quarter-period, ˜250 kA GenASIS driver are presented. Three different foil designs are tested to determine the effects of initial structure on pinch outcome. Foil X-pinch data are also presented alongside the results from wire X-pinches with comparable mass. The X-ray flux and temporal profile of the emission from foil X-pinches differed significantly from that of wire X-pinches, with all emission from the foil X-pinches confined to a ˜3 ns period as opposed to the delayed, long-lasting electron beam emission common in wire X-pinches. Spectroscopic data show K-shell as well as significant L-shell emission from both foil and wire X-pinches. Fits to synthetic spectra using the SCRAM code suggest that pinching foil X's produced a ˜1 keV, ne ≥ 1023 cm-3 plasma. The spectral data combined with the improved reliability of the source timing, flux, and location indicate that foil X-pinches generate a reproducible, K-shell point-projection radiography source that can be easily modified and tailored to suit backlighting needs across a variety of applications.

  9. A summary of the Berkeley and Livermore pinch programs

    Energy Technology Data Exchange (ETDEWEB)

    Colgate, Stirling A [University of California Radiation Laboratory, Livermore, CA (United States)

    1958-07-01

    In order to progress toward practical thermonuclear devices, the principal objective must be to prolong containment times by improving the electrical conductivity of the plasma. Those pinch configurations which are grossly unstable are, of course, unsuitable for practical thermonuclear work. Therefore our purely dynamic experiments are conducted only to study basic shock heating and instability mechanisms. Our basic evaluation of progress in pinch-type experiments is the reduction of the dissipation rate of the magnetic fields. The present pessimistic viewpoint is that most of the pinch devices that depend upon high current density within the plasma are beset with an enhanced dissipation rate which is disastrous to pinch containment. This dissipation is derived either from an electron plasma current instability or from hydromagnetic turbulence. Both have been predicted in theory and observed in experiment. Studies have been presented for the following cases: linear and toroidal pinch experiments; sheet pinch devices of modest size; homopolar geometry; shock heating and screw dynamic pinch.

  10. Radiation hydrodynamics of z-pinch plasmas

    International Nuclear Information System (INIS)

    Davis, J.

    1993-01-01

    Over the years there has been a sustained interest in and fascination with Z-pinch plasmas. Whether the interest is in radiation source development, fusion plasmas, or basic research there exits an extensive bibliography of literature promulgating and perpetuating a variety of claims regarding the performance of Z-pinch plasmas. In this paper an attempt will be made to present a coherent picture of the documented and commonly held views for a class of Z-pinch plasmas concerned primarily with soft x-ray radiation source development. Many of the issues and findings are common to Z-pinch plasmas in general but the attention here will be focused on gas puffs and multiple wire arrays. The role and importance of radiation on the dynamics and the interplay between the radiation and the dynamics will also be presented and discussed. A number of comparisons with experimental results will be made with 0-, 1-, and 2-D numerical simulations for several pulsed power drivers ranging in current from several mega-amps to 10's of mega-amps for a variety of risetimes and load materials

  11. Self-stabilized pinch (SSP) concept

    International Nuclear Information System (INIS)

    Sugisaki, Kiwamu; Hirano, Keiichi.

    1985-01-01

    Self-Stabilized pinch (SSP) consept is revealed. SSP providcs many attractive features for application to a fusion reactor. Design studies for high temperature plasma production are carried out. Use of adiabatic compression leads to a remarkable reduction of required power source. (author)

  12. Scylla IV-P theta pinch

    International Nuclear Information System (INIS)

    Bailey, A.G.; Chandler, G.I.; Ekdahl, C.A. Jr.; Lillberg, J.W.; Machalek, M.D.; Seibel, F.T.

    1976-01-01

    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

  13. 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.

  14. The Analisis Sentimen Sosial Media Twitter Dengan Algoritma Machine Learning Menggunakan Software R

    Directory of Open Access Journals (Sweden)

    Jaka Aulia Pratama

    2017-10-01

    Full Text Available Media sosial adalah wadah untuk mengungkapkan opini terhadap suatu topik tertentu. Ketersediaan informasi dan opini dari para pengguna media sosial merupakan kumpulan dokumen data berupa teks yang amat sangat besar dan berguna untuk kepentingan penelitian maupun membuat suatu keputusan bagi pihak – pihak tertentu. Text Mining bisa didefinisikan sebagai proses penggalian informasi di mana pengguna berinteraksi dengan kumpulan dokumen dari waktu ke waktu dengan menggunakan suatu alat analisis. Analisis sentimen atau Opinion Mining adalah salah satu studi di bidang komputasi yang berhubungan dengan kasus publik mengenai opini, penilaian, sikap, dan emosi. Penelitian ini akan menggunakan metode Machine Learning pada analisis sentimen pengguna layanan jejaring sosial Twitter terhadap Donald Trump dan Barack Obama dalam 20000 tweets. Nilai akurasi metode Machine Learning yang diperoleh cukup tinggi yaitu 87.52% untuk Data Training dan 87.4% untuk Data Testing.

  15. PENERAPAN ANALISIS SWOC DALAM RENCANA STRATEGIS PENDIDIKAN

    Directory of Open Access Journals (Sweden)

    Hardianto -

    2018-01-01

    Full Text Available Analisis SWOC merupakan salah satu langkah yang bisa diambil dalam membuat sebuah rencana strategis pendidikan. Analisis ini dilakukan untuk melihat secara mendalam situasi internal dan eksternal organisasi. Situasi internal yang dilihat adalah kekuatan (Strenghts dan kelemahan (Weaknesses organisasi pendidikan. Situasi eksternal berupa peluang (Opportinities dan tantangan (Challenges. Untuk membuat sebuah rencana strategis yang baik dapat dilakukan dengan menganalisis setiap kekuatan, kelemahan, peluang dan tantangan. Teknik kartu salju (snow card bisa digunakan dalam melakukan analisis SWOC. Hasil analisis tersebut nantinya akan melahirkan kombinasi strategi kekuatan-peluang, kekuatan-tantangan, kelemahan-peluang dan kelemahan-tantangan.

  16. Analisis Cadangan Devisa Indonesia

    Directory of Open Access Journals (Sweden)

    Lusia Bunga Uli

    2016-09-01

    Full Text Available Abstract This study aims to determine the relationship between variables export, import, and exchange rate against Foreign Exchange Reserves in Indonesia. The data used in the empirical study of a sequence of data monthly time of year 2011.01 through 2014.12 from Bank Indonesia and the Central Statistics Agency (BPS. The analysis tool used is Auto Regression Vector Model (VAR. The results of this study indicate that the one-way relationship between the variables of foreign reserves and export. Then one-way relationship between exchange rate and exports. Lastly, there is a two-way relationship between imports and foreign exchange reserves, two-way relationship between exchange rate and foreign exchange reserves, two-way relationship between imports and exports, two-way relationship between the exchange rate and imports. The results also showed foreign exchange reserves are significantly influenced by the movement itself at a probability of 1 %. Export variable negative and not significantly affect the foreign exchange reserves. While imports of positive and not significant to the foreign exchange reserves. Foreign Exchange Reserves Indonesia is positively influenced by the exchange rate and not significant. Keywords: Foreign exchange reserves, exports, imports, exchange rate   Abstrak. Penelitian ini bertujuan untuk mengetahui seberapa keterkaitan antar variabel ekspor, impor, dan nilai tukar rupiah terhadap Cadangan Devisa Indonesia. Data yang digunakan dalam kajian empiris ini merupakan data runtutaan waktu bulanan dari tahun 2011.01 sampai 2014. 12 yang berasal dari Bank Indonesia dan Badan Pusat Statistik (BPS. Alat analisis yang digunakan yaitu Vector Autoregression Model (VAR. Hasil dari penelitian ini menunjukkan bahwa hubungan searah antara variabel cadangan devisa ke ekspor. Lalu hubungan searah antara kurs terhadap ekspor Terakhir, terdapat hubungan dua arah antara impor dan cadangan devisa, hubungan dua arah antara kurs dan cadangan

  17. 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...... gradient length, with an experimental scaling for the pinch number being -Rvpinch/χφ = 1.2R/Ln +1.4. There is no dependence of the pinch number on collisionality, whereas the pinch seems to depend weakly on q-profile, the pinch number decreasing with increasing q. The Prandtl number was not found to depend...... either on R/Ln, collisionality or on q. The gyro-kinetic simulations show qualitatively similar dependence of the pinch number on R/Ln, but the dependence is weaker in the simulations. Gyro-kinetic simulations do not find any clear parametric dependence in the Prandtl number, in agreement...

  18. LASL toroidal reversed-field pinch programme

    International Nuclear Information System (INIS)

    Baker, D.A.; Buchenauer, C.J.; Burkhardt, L.C.

    1979-01-01

    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)

  19. LASL toroidal reversed-field pinch program

    International Nuclear Information System (INIS)

    Baker, D.A.; Buchenauer, C.J.; Burkhardt, L.C.

    1978-01-01

    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 over half of 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 are 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

  20. Evolution of the MHD sheet pinch

    International Nuclear Information System (INIS)

    Matthaeus, W.H.; Montgomery, D.

    1979-01-01

    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

  1. Pinching Solutions of Slender Cylindrical Jets

    Science.gov (United States)

    1993-06-01

    NASA Langley Research Center, Hampton, VA 23681.2This research was supported in part by Fondo Nacional de Desarrollo Cientifico y Tecnologico (FONDE...concentrate on inviscid irrotational flows of liquid jets. A review article has been written by Bogy [2]. Of relevance is also the work of Chandrasekhar...equations become elliptic and allow the possibility of admissible pinching solutions described in this article . It is interesting to find that for jets

  2. ZAPP: Z-pinch atomic physics program

    International Nuclear Information System (INIS)

    Reed, K.

    1983-01-01

    High-density and high-temperature plasmas have been produced in a z-pinch with a hollow gas puff. A number of interesting atomic-physics phenomena occur in these plasmas and some of these phenomena provide important diagnostic information for characterizing the plasmas. We have been interested in collisions of high-energy electrons with highly stripped ions in these plasmas. Such collisions may produce a population inversion which could result in stimulated emission in the x-ray regime

  3. Turbulent transport in reversed field pinches

    International Nuclear Information System (INIS)

    Christiansen, J.P.; Roberts, K.V.

    1976-01-01

    MHD stability of the Reversed Field Pinch (RFP) relies on reversal of the toroidal field component in the outer plasma region. Interest in this configuration comes from its potential economic advantages as a thermonuclear reactor, since compared to a Tokamak the RFP supports a higher value of β, the ratio between plasma and total magnetic pressure. Results of computations on the time-evolution of the RFP using a 1D MHD model are reported. (orig./GG) [de

  4. Analisis Semiotik Sajak Bulang Cahaya

    Directory of Open Access Journals (Sweden)

    Junaidi Junaidi

    2014-11-01

    Full Text Available Penelitian ini bertujuan menggali makna tanda yang terdapat dalam sajak Bulang Cahaya karya Rida K Liamsi. Untuk menggali makna itu, pendekatan analisis semiotik Roland Barthes digunakan. Hasil penelitian menunjukkan bahwa sajak ini berisi tanda-tanda bersumber dari kosa kata Melayu lama. Sajak ini juga berisi simbol-simbol yang berkaitan dengan kehidupan orang Melayu. Penggunaan kata-kata Melayu lama dan simbol Melayu memperkuat setting Melayu dalam sajak ini. Analisis makna menunjukkan bahwa seseorang merasakan kedukaan sangat mendalam ketika cintanya harus berakhir, tetapi ia terus merasakan kerinduan dengan kekasihnya yang telah pergi. Mitos cinta yang terdapat dalam pusinya adalah orang tahu bahwa putus cinta itu menyakitkan tetapi orang tetap saja jatuh cinta.

  5. On the instability increments of a stationary pinch

    International Nuclear Information System (INIS)

    Bud'ko, A.B.

    1989-01-01

    The stability of stationary pinch to helical modes is numerically studied. It is shown that in the case of a rather fast plasma pressure decrease to the pinch boundary, for example, for an isothermal diffusion pinch with Gauss density distribution instabilities with m=0 modes are the most quickly growing. Instability increments are calculated. A simple analytical expression of a maximum increment of growth of sausage instability for automodel Gauss profiles is obtained

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

    International Nuclear Information System (INIS)

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

    2008-01-01

    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', nm i U # parallel# R/B 2 , 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.

  7. Analisis Industri Ritel Di Indonesia

    OpenAIRE

    Soliha, Euis

    2008-01-01

    This article presents an overview the analisys of retail industry in Indonesia.Retail industry in Indonesia grow rapidly. Industrial presence of modern retailbasically exploits public shopping pattern especially middle-weight and to which donot want to mill around in traditional market. Analysis Five Forces is used toanalysis retail industry. Analysis five force is bargaining power of buyers,bargaining power of suppliers, threat of new entrants, threat of new substituteproducts, and rivalry a...

  8. X-ray backlighting of two-wire Z-pinch plasma using X-pinch

    International Nuclear Information System (INIS)

    Tong, Zhao; Xiao-Bing, Zou; Ran, Zhang; Xin-Xin, Wang

    2010-01-01

    Two 50-μm Mo wires in parallel used as a Z-pinch load are electrically exploded with a pulsed current rising to 275 kA in 125 ns and their explosion processes are backlighted using an X-pinch as an x-ray source. The backlighting images show clearly the processes similar to those occurring in the initial stages of a cylindrical wire-array Z-pinch, including the electric explosion of single wires characterised by the dense wire cores surrounded by a 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 the current centroid, the formation of the precursor plasma column with a twist structure something like that of higher mode instability, especially the kink instability (m = 1). (fluids, plasmas and electric discharges)

  9. ANALISIS POSITIONING RESTORAN CEPAT SAJI

    Directory of Open Access Journals (Sweden)

    Osa Omar Sharif

    2017-04-01

    Full Text Available Penelitian ini bertujuan untuk meneliti positioning restoran cepat saji McDonald's, Kentucky Fried Chicken, California Fried Chicken, A&W, dan Texas Chicken. Penelitian dilakukan di Kota Bandung dengan mengambil sebanyak 400 responden. Analisis yang digunakan dalam penelitian ini adalah analisis multidimensional scaling, analisis memberikan gambaran positioning dari restoran cepat saji yang ditampilkan dalam perceptual map. Restoran cepat saji yang memiliki layanan paling baik adalah McD dan yang memiliki layanan paling buruk adalah CFC. Restoran cepat saji yang memiliki rasa makanan paling enak adalah McD dan yang memiliki rasa makanan tidak enak adalah CFC. KFC dinilai paling ideal karena selalu berhasil menduduki peringkat satu dan dua jika dilihat dari sudut pandang restoran cepat saji yang lain. Pesaing terdekat McD adalah KFC. McD mendapatkan ranking pertama dari segi atribut layanan, kebersihan, variasi makanan, dan rasa makanan. Dengan posisi seperti ini McD seharusnya tetap menjaga kualitas layanan, kebersihan, variasi makanan, dan rasa makanan agar konsumen tetap memilih untuk datang ke McD. KFC sebaiknya tetap menjaga suasana yang membuat konsumen nyaman akan suasana di dalam atau diluar restoran

  10. High-density fusion and the Z-pinch

    International Nuclear Information System (INIS)

    Hartman, C.W.; Eddleman, J.L.; Munger, R.H.

    1975-01-01

    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 10 21 cm 3 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)

  11. On the Heating of Ions in Noncylindrical Z-Pinches

    Science.gov (United States)

    Svirsky, E. B.

    2018-01-01

    The method proposed here for analyzing processes in a hot plasma of noncylindrical Z-pinches is based on separation of the group of high-energy ions into a special fraction. Such ions constitute an insignificant fraction ( 10%) of the total volume of the Z-pinch plasma, but these ions contribute the most to the formation of conditions in which the pinch becomes a source of nuclear fusion products and X-ray radiation. The method allows a quite correct approach to obtaining quantitative estimates of the plasma parameters, the nuclear fusion energy yield, and the features of neutron fluxes in experiments with Z-pinches.

  12. Plasma dynamics in a staged pinch device

    International Nuclear Information System (INIS)

    Khattak, N.A.D.; Ahmed, Z.; Mirza, A.M.; Murtaza, G.

    1998-01-01

    Plasma parameters in fiber initiated fast and dense theta-pinch plasma driven by an annular finite-thickness gas-puff Z-pinch are studied. The imploding gas-puff Z-pinch plasma traps an axial magnetic field B/sub z/, compressing it to large values (of the order of several megagauss) in an extremely short time. The rapidly changing magnetic flux of this field induces an azimuthal current on the surface of the coaxially placed fiber, with a rise time an order of magnitude shorter than the applied Z-pinch current. The shorter rise time of the current stabilizes the pinch against sausage mode of MHD instabilities. Our numerical results demonstrate that for a relatively thick gas-puff layer, the compression occurs before the current saturates. At the peak compression the fuel densities of the order of 10/sup 25/ cm/sup -3/ and temperature above 10 keV can be achieved on a time scale of 0.1 nanoseconds, yielding the Lawson Criterion parameters n tau is approximately equal to 10/sup 14/ sec cm/sup -3/ for D-T fuel. The snow-plow effect incorporated in our model exercise a strong influence on the onset and growth rate of sausage and Rayleigh-Taylor (R-T) modes of instabilities. Imposing a rotational velocity on the outer thin gas-puff plasma can control the Rayleigh-Taylor instability. Numerical results indicate that the choice of the spin velocity is critical. Large values of the spin velocity, though provide stabilization against the R-T instability at the final stage of compression, however, it adversely reduce the plasma parameters so essential to achieve controlled fusion. Our analysis, therefore, suggests that a judicious choice of the spin velocity is necessary to obtain the desired temperature and density, especially when we seed D-T fiber plasma with a small fraction of high-Z Kr impurity to initiate the radiative collapse. (author)

  13. Analisis Gameplay Game Genre Virtual Pet

    Directory of Open Access Journals (Sweden)

    Abi Senoprabowo

    2015-02-01

    Full Text Available Game adalah struktur interaktif yang membuat pemain berjuang menuju sebuah tujuan. Game dapat memberikan emosi dan mood, menghubungkan dengan orang latihan, sarana latihan, serta dapat memberikan edukasi. Salah satu game yang berkembang saat ini adalah game bergenre Virtual pet. Game virtual pet merupakan game simulasi memelihara sesuatu. Virtual pet memiliki gameplay yang menarik dan menyenangkan yang membuat pemain seolah-olah benar-benar memiliki binatang peliharaan mereka sendiri. Virtual pet dianggap oleh sebagian besar penggunanya dapat memberikan kegembiraan serta rasa kasih sayang karena tingkat interaksinya yang baik. Banyak pengembang game pemula yang mengembangkan genre ini sebagai game yang mereka buat karena kemudahaan dan tingkat penggunanya yang banyak. Akan tetapi banyak dari pengembang game pemula tidak memperhatikan tingkat keberlanjutan game virtual pet yang mereka buat sehingga membuat pemain cepat bosan. Pada penelitian ini, analisis game bergenre virtual pet yang sudah sukses dibuat seperti Zombigotchi, Tamagotchi Unicorn, dan Bird Land, diharapkan dapat membantu para pengembang game pemula agar mengetahui cara merancang dan mengembangkan game virtual pet dengan baik. Kata Kunci: game, gameplay, virtual pet

  14. 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.

  15. Deuterated fibre Z-pinch on the S-300 generator

    NARCIS (Netherlands)

    Klir, D.; Kravarik, J.; Kubes, P.; Bakshaev, Yu L.; Blinov, P. I.; Chernenko, A. S.; Danko, S. A.; Korolev, V. D.; Ustroev, G. I.; Ivanov, M. I.; Cai, Hongchun

    2006-01-01

    Dense Z-pinch experiments were carried out on the S-300 generator (3.5 MA, 100 ns, 0.15 Omega) at the Kurchatov Institute in Moscow. The experiments were performed at a peak current of 2 MA with a rise time of about 100 ns. The Z-pinch was formed from a deuterated polyethylene fibre of 100 mu m

  16. Self-pinched lithium beam transport experiments on SABRE

    International Nuclear Information System (INIS)

    Hanson, D.L.; Olson, C.L.; Poukey, J.W.; Shokir, I.; Cuneo, M.E.; Menge, P.R.; Johnston, R.R.; Welch, D.R.

    1996-01-01

    Self-pinched transport of ion beams has many advantages for ion-driven ICF applications involving high yield and energy production. The authors are currently preparing for a self-pinched lithium beam transport experiment on the SABRE accelerator. There are three transport elements that must eventually be demonstrated: (1) efficient lithium beam generation and ballistic transport to a focus at the self-pinched transport channel entrance; (2) self-pinched transport in the channel, requiring optimized injection conditions and gas breakdown; and (3) self-pinched transport of the equilibrated beam from the channel into free space, with associated aiming and stability considerations. In the present experiment, a hollow annular lithium beam from an applied-B extraction ion diode will be focused to small radius (r ≤ 2 cm) in a 60 cm long ballistic focus section containing argon gas at a pressure of a few Torr. The self-pinched transport channel will contain a low pressure background gas of 10--40 mTorr argon to allow sufficient net current to confine the beam for long distance transport. IPROP simulations are in progress to optimize the design of the ballistic and self-pinched transport sections. Progress on preparation of this lithium self-pinched transport experiment, including a discussion of transport system design, important gas breakdown issues, and diagnostics, will be presented

  17. Effect of transcranial magnetic stimulation on force of finger pinch

    Science.gov (United States)

    Odagaki, Masato; Fukuda, Hiroshi; Hiwaki, Osamu

    2009-04-01

    Transcranial magnetic stimulation (TMS) is used to explore many aspects of brain function, and to treat neurological disorders. Cortical motor neuronal activation by TMS over the primary motor cortex (M1) produces efferent signals that pass through the corticospinal tracts. Motor-evoked potentials (MEPs) are observed in muscles innervated by the stimulated motor cortex. TMS can cause a silent period (SP) following MEP in voluntary electromyography (EMG). The present study examined the effects of TMS eliciting MEP and SP on the force of pinching using two fingers. Subjects pinched a wooden block with the thumb and index finger. TMS was applied to M1 during the pinch task. EMG of first dorsal interosseous muscles and pinch forces were measured. Force output increased after the TMS, and then oscillated. The results indicated that the motor control system to keep isotonic forces of the muscles participated in the finger pinch was disrupted by the TMS.

  18. Influence of pinches on magnetic reconnection in turbulent space plasmas

    Science.gov (United States)

    Olshevsky, Vyacheslav; Lapenta, Giovanni; Markidis, Stefano; Divin, Andrey

    A generally accepted scenario of magnetic reconnection in space plasmas is the breakage of magnetic field lines in X-points. In laboratory, reconnection is widely studied in pinches, current channels embedded into twisted magnetic fields. No model of magnetic reconnection in space plasmas considers both null-points and pinches as peers. We have performed a particle-in-cell simulation of magnetic reconnection in a three-dimensional configuration where null-points are present nitially, and Z-pinches are formed during the simulation. The X-points are relatively stable, and no substantial energy dissipation is associated with them. On contrary, turbulent magnetic reconnection in the pinches causes the magnetic energy to decay at a rate of approximately 1.5 percent per ion gyro period. Current channels and twisted magnetic fields are ubiquitous in turbulent space plasmas, so pinches can be responsible for the observed high magnetic reconnection rates.

  19. Integration thermal processes through Pinch technology

    International Nuclear Information System (INIS)

    Rios H, Carlos Mario; Grisales Rincon, Rogelio; Cardona, Carlos Ariel

    2004-01-01

    This paper presents the techniques of heat integration used for process optimization, their fortresses and weaknesses during the implementation in several specific process are also discussed. It is focused to the pinch technology, explaining algorithms for method applications in the industry. The paper provides the concepts and models involved in different types of commercial software applying this method for energy cost reduction, both in design of new plants and improve of old ones. As complement to benefits of the energy cost reduction it is analysed other favorable aspects of process integration, as the emissions waste reduction and the combined heat end power systems

  20. The Magpie dense z-pinch project

    International Nuclear Information System (INIS)

    Chittenden, J.; Choi, P.; Mitchell, I.; Dangor, A.E.; Haines, M.G.

    1990-01-01

    The authors present a design study on the Mega Ampere Generator for Plasma Implosion Experiments (MAGPIE), a project currently under construction at Imperial College London, to study radiative collapse of a dense Z-pinch plasma created from a 20 um diameter cryogenic hydrogen fiber. The 2 TW generator is composed of four individual 2.4 MV Marx banks of the HERMES III type design with a maximum stored energy of 336 kJ. They drive four 5 ohm Pulse Forming Lines which are combined into a single 1.25 MA in 150 ns to a 150 nH load

  1. MHD simulations of molybdenum X-pinches

    International Nuclear Information System (INIS)

    Ivanenkov, G.V.; Stepnevski, V.

    2002-01-01

    One investigates into compression of molybdenum X-pinches applying numerical MHD-models with parabolic and conical initial geometry. The second model describing plasma axial motion in greater detail offers a real geometry of a discharge and is applicable to loads characterized by higher masses in contrast to the first one. Both models enabled to describe all basic phases of compression including origination of a minidiode, occurrence of a narrow neck, microexplosion of a hot point and origination of shock waves followed by sausage instability [ru

  2. Numerical studies of the linear theta pinch

    International Nuclear Information System (INIS)

    Brackbill, J.U.; Menzel, M.T.; Barnes, D.C.

    1975-01-01

    Aspects of several physical problems associated with linear theta pinches were studied using recently developed numerical methods for the solution of the nonlinear equations for time-dependent magnetohydrodynamic flow in two- and three-dimensions. The problems studied include the propagation of end-loss produced rarefaction waves, the flow produced in a proposed injection experiment geometry, and the linear growth and nonlinear saturation of instabilities in rotating plasmas, all in linear geometries. The studies illustrate how numerical computations aid in flow visualization, and how the small amplitude behavior and nonlinear fate of plasmas in unstable equilibria can be connected through the numerical solution of the dynamical equations. (auth)

  3. Electron temperature measurement in Z-pinch

    International Nuclear Information System (INIS)

    Gerusov, A.V.; Orlov, M.M.; Terent'ev, A.R.; Khrabrov, V.A.

    1987-01-01

    Measurement of temperature of emitting plasma sheath in noncylindrical Z-pinch in neon at the stage of convergence to the axis, based on comparing the intensity of spectral lines belonging to Ne1, Ne2, is performed. Line intensity relation dependence was determined using calculations according to emitting-collision model. Spectra were recorded by electron-optical converter and relative intensity was determined by subsequent photometry of photolayer. Cylindric symmetrical MHD-calculations during which temperature and the observed line intensity relation were determined, are conducted

  4. Confinement dynamics in the reversed field pinch

    International Nuclear Information System (INIS)

    Schoenberg, K.F.

    1988-01-01

    The study of basic transport and confinement dynamics is central to the development of the reversed field pinch (RFP) as a confinement concept. Thus, the goal of RFP research is to understand the connection between processes that sustain the RFP configuration and related transport/confinement properties. Recently, new insights into confinement have emerged from a detailed investigation of RFP electron and ion physics. These insights derive from the recognition that both magnetohydrodynamic (MHD) and electron kinetic effects play an important and strongly coupled role in RFP sustainment and confinement dynamics. In this paper, we summarize the results of these studies on the ZT-40M experiment. 8 refs

  5. Reversed-Field Pinch plasma model

    International Nuclear Information System (INIS)

    Miley, G.H.; Nebel, R.A.; Moses, R.W.

    1979-01-01

    The stability of a Reversed-Field Pinch (RFP) is strongly dependent on the plasma profile and the confining sheared magnetic field. Magnetic diffusion and thermal transport produce changing conditions of stability. Despite the limited understanding of RFP transport, modelling is important to predict general trends and to study possible field programming options. To study the ZT-40 experiment and to predict the performance of future RFP reactors, a one-dimensional transport code has been developed. This code includes a linear, ideal MHD stability check based on an energy principle. The transport section integrates plasma profiles forward in time while the stability section periodically checks the stability of the evolving plasma profile

  6. Interchange stability of noncircular reversed field pinches

    International Nuclear Information System (INIS)

    Skinner, D.A.; Prager, S.C.; Todd, A.M.M.

    1987-08-01

    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

  7. ANALISIS PERBAIKAN SISTEM PENTANAHAN TELEKOMUNIKASI

    Directory of Open Access Journals (Sweden)

    Umar Umar

    2015-04-01

    Hasil dari penelitian ini adalah perbaikan sistem pentanahan site Kampung Baru dengan menggunakan konfigurasi single point connection window (SPCW, untuk mengamankan sistem telekomunikasi dari kebocoran arus dan petir serta imbasnya.  Perbaikan sistem pentanahan di site Kampung Baru menggunakan banyak elektroda yang membentuk persegi dikarenakan topografi tempat di sana yang memungkinkan dan efektif adalah menggunakan sistem tersebut. Berdasarkan hasil analisis dan perhitungan perbaikan sistem di site Kampung Baru, didapatkan nilai perhitungan sistem pentanahan adalah 1.34 Ohm serta pengukurannya 1.21-1.25 Ohm.

  8. Rotational instability in a linear theta pinch

    International Nuclear Information System (INIS)

    Ekdahl, C.; Bartsch, R.R.; Commisso, R.J.; Gribble, R.F.; McKenna, K.F.; Miller, G.; Siemon, R.E.

    1980-01-01

    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

  9. Engineering feasibility evaluation of a peristaltic pinch

    International Nuclear Information System (INIS)

    Boicourt, G.P.

    1977-04-01

    A recent proposal for reducing the end loss of a linear theta pinch is to produce moving magnetic mirrors at the coil ends. The concept entails the sequential pulsing of an axially arranged series of two-turn coaxial coils. The electrical design of such a system presents some unique problems. Ideally, the individual pulse circuits should be completely independent. This would facilitate the design by eliminating interactive effects. In practice, the circuits must be interconnected through isolating inductors to enable the production of a uniform biasing magnetic field. Moreover, the coils must be located physically close together. This produces strong magnetic coupling between the pulse circuits, which can seriously affect the shape and speed of the inward-moving magnetic-mirror field. Possible systems were modeled for the NET-2 circuit analysis code. The models took account of the inductive coupling between the individual circuits in the model. The results show that an increasing magnetic mirror can be produced provided the radius of the theta pinch is not too great compared to the intercoil spacing. The peristaltic field can be maintained for several cycles in the inner coils. The voltage hold-off requirements on the pulse circuit switches are found to be severe, but not impossible to meet

  10. Moderately reverberant learning ultrasonic pinch panel.

    Science.gov (United States)

    Nikolovski, Jean-Pierre

    2013-10-01

    Tactile sensing is widely used in human-computer interfaces. However, mechanical integration of touch technologies is often perceived as difficult by engineers because it often limits the freedom of style or form factor requested by designers. Recent work in active ultrasonic touch technologies has made it possible to transform thin glass plates, metallic sheets, or plastic shells into interactive surfaces. The method is based on a learning process of touch-induced, amplitude-disturbed diffraction patterns. This paper proposes, first, an evolution in the design with multiple dipole transducers that improves touch sensitivity or maximum panel size by a factor of ten, and improves robustness and usability in moderately reverberant panels, and second, defines a set of acoustic variables in the signal processing for the evaluation of sensitivity and radiating features. For proof of concept purposes, the design and process are applied to 3.2- and 6-mm-thick glass plates with variable damping conditions. Transducers are bonded to only one short side of the rectangular substrates. Measurements show that the highly sensitive free lateral sides are perfectly adapted for pinch-touch and pinch-slide interactions. The advantage of relative versus absolute touch disturbance measurement is discussed, together with tolerance to abutting contaminants.

  11. Material testing in a linear theta pinch

    International Nuclear Information System (INIS)

    Alani, R.; Azodi, H.; Naraghi, M.; Safaii, B.; Torabi-Fard, A.

    1983-01-01

    The interaction of stainless steel 316 and Inconel 625 alloys has been investigated with a thermonuclear-like plasma, n = 10 16 cm -3 and Tsub(i) = 1 keV, generated in the Alvand I linear theta pinch. The average power flux is 10 7 W/cm 2 and the interaction time nearly one μs. A theoretical analysis based on the formation of an observed impurity layer near the material, has been used to determine the properties of the impurity layer and the extent of the damage on the material. Although arcing has been observed, the dominant damage mechanism has been assessed to be due to evaporation. Exposure to single shots has produced very heavily defective areas and even surface cracks on the SS 316 sample, but no cracks were observed on Inconel 625 after exposure to even 18 shots. On the basis of temperature rise and evaporation a comparison is made among materials exposed to plasmas of a theta pinch, shock tube, present generation tokamak and an anticipated tokamak reactor. (orig.)

  12. Electrostatic turbulence in the Z pinch corona

    International Nuclear Information System (INIS)

    Terry, R.E.

    1994-01-01

    The microstability of electrostatic waves in the periphery of a Z pinch is formulated and resolved for a new class of Vlasov meta-equilibria admitting self-similar solutions in the electron gyrokinetic limit. These equilibria are subject to strong radial motions, and a mild deviation from charge neutrality arises to maintain ion acceleration close to that of the magnetized electrons. A unique class of profiles in density, axial current, temperature, and drift speed defines these equilibria. They are characterized by (i) the interior pinch current, (ii) the interior number density, (iii) the parallel and perpendicular temperatures, (iv) the exterior axial electric field value at the initial time, and (v) the radial ion acceleration relative to that of the electrons. Unstable ion sound waves arise in this medium by coupling radial and axial free energy to azimuthal longitudinal oscillations. The waves grow only for a limited range of radial or axial Exb/B drift speeds and electron temperatures. The growth rate, which can be as large as 0.115ω pi , is found to scale proportional to plasma frequency over the density range from 10 12 to 10 18 ions cm -3

  13. Processes governing pinch formation in diodes

    International Nuclear Information System (INIS)

    Blaugrund, A.E.; Cooperstein, G.; Goldstein, S.A.

    1975-01-01

    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

  14. An ultra miniature pinch-focus discharge

    International Nuclear Information System (INIS)

    Soto, L.; Pavez, C.; Moreno, J.; Pavez, C.; Barbaglia, M.; Clausse, A.

    2004-01-01

    As a way to investigate the minimum energy to produce a pinch plasma focus discharge, an ultra miniature device has been designed and constructed (nano focus NF: 5 nF, 5-10 kV, 5-10 kA, 60-250 mJ, 16 ns time to peak current). Sub-millimetric anode radius covered by a coaxial insulator were used for experiments in hydrogen. Evidence of pinch was observed in electrical signals in discharges operating at 60 mJ. A single-frame image converter camera (4 ns exposure) was used to obtain plasma images in the visible range. The dynamics observed from the photographs is consistent with: a) formation of a plasma sheath close to the insulator surface, b) fast axial motion of the plasma sheath, c) radial compression over the anode, and d) finally the plasma is detached from the anode in the axial direction. The total time since stage a) to d) was observed to be about 30 ns. X ray and neutron emission is being studied. Neutron yield of the order of 10 3 neutrons per shot is expected for discharges operating in deuterium at 10 kA. (authors)

  15. Analysis of pinching in deterministic particle separation

    Science.gov (United States)

    Risbud, Sumedh; Luo, Mingxiang; Frechette, Joelle; Drazer, German

    2011-11-01

    We investigate the problem of spherical particles vertically settling parallel to Y-axis (under gravity), through a pinching gap created by an obstacle (spherical or cylindrical, center at the origin) and a wall (normal to X axis), to uncover the physics governing microfluidic separation techniques such as deterministic lateral displacement and pinched flow fractionation: (1) theoretically, by linearly superimposing the resistances offered by the wall and the obstacle separately, (2) computationally, using the lattice Boltzmann method for particulate systems and (3) experimentally, by conducting macroscopic experiments. Both, theory and simulations, show that for a given initial separation between the particle centre and the Y-axis, presence of a wall pushes the particles closer to the obstacle, than its absence. Experimentally, this is expected to result in an early onset of the short-range repulsive forces caused by solid-solid contact. We indeed observe such an early onset, which we quantify by measuring the asymmetry in the trajectories of the spherical particles around the obstacle. This work is partially supported by the National Science Foundation Grant Nos. CBET- 0731032, CMMI-0748094, and CBET-0954840.

  16. Semiotika Teks: Sebuah Pendekatan Analisis Teks

    Directory of Open Access Journals (Sweden)

    Yasraf Amir Piliang

    2004-12-01

    tanda-tanda yang membentuk apa yang disebut sebagai ‘teks’. Analisis teks, menurut Roland Barthes, akan menghasilkan makna denotatif, yakni makna tanda yang bersifat eksplisit, dan makna konotatif, yaitu makna tanda lapis kedua yang bersifat implisit.

  17. 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.

  18. ANALISIS DAYA SAING KEDELAI INDONESIA

    Directory of Open Access Journals (Sweden)

    Sarwono Sarwono

    2014-09-01

    Full Text Available RCA (Revealed Comparative Advantage index of soybean in Indonesia from 1983 up to 2013 is less than one, mostly. It means that the competitiveness of soybean in Indonesia is low. The purpose of this study is to analyze the factors influence the soybean competitiveness. OLS (Ordinary Least Square was used as the analysis method. Hypotheses test based on that analysis model is not bias, so that, classic divergence test is needed. It is for getting the Best Linier Unbiased Estimator (BLUE appraisal. T statistic and F statistic were also applied. The result of this research shows that production and export have positive and significant influence. In addition, exchange rate and government policy do not influence the Indonesia soybean competitiveness.Indeks RCA (Revealed Comparative Advantage kedelai Indonesia dari tahun 1983-2013 kecenderungan bernilai kurang dari satu yang berarti daya saing kedelai Indonesia rendah.Penelitian ini bertujuan untuk menganalisis faktor-faktor yang mempengaruhi daya saing kedelai Indonesia.Metode analisis yang digunakan adalah Ordinary Least Square (OLS.Pengujian hipotesis berdasarkan model analisis tersebut tidak bias maka perlu dilakukan uji penyimpangan klasik yang tujuannya agar diperoleh penaksiran yang bersifat Best Linier Unbiased Estimator (BLUE.Pengujian statistik menggunakan uji t statistikdan uji f statistik.Hasil penelitian ini menunjukkan bahwa produksi dan ekspor berpengaruh secara positif dan signifikan terhadap daya saing kedelai Indonesia. Nilai tukar rupiah dan kebijakan pemerintah tidak berpengaruh terhadap daya saing kedelai Indonesia.

  19. Analisis Harmonisa Inverter PWM Satu Fasa

    OpenAIRE

    Rejeki Simanjorang

    2008-01-01

    Pada tesis ini dianalisis harmonisa inverter PWM satu fasa. Inverter PWM satu fasa yang akan ditinjau adalah inverter satu fasa jembatan penuh (konvensional) dan inverter komposit. Analisis difokuskan pada penentuan pola penyaklaran yang optimum agar pembangkitan harmonisa dan switching losses inverter rendah. Untuk menentukan pola penyaklaran optimum maka dilakukan analisis yang berbasis pada rangkaian ekivalen harmonisa inverter satu fasa. Dengan menggunakan pola penyaklaran optimum, kedua ...

  20. Linear pinch driven by a moving compact torus

    International Nuclear Information System (INIS)

    Hartman, C.W.; Hammer, J.H.; Eddleman, J.L.

    1984-01-01

    In principle, a Z-pinch of sufficiently large aspect ratio can provide arbitrarily high magnetic field intensity for the confinement of plasma. In practice, however, achievable field intensities and timescales are limited by parasitic inductances, pulse driver power, current, voltage, and voltage standoff of nearby insulating surfaces or surrounding gas. Further, instabilities may dominate to prevent high fields (kink mode) or enhance them (sausage mode) but in a nonuniform and uncontrollable way. In this paper we discuss an approach to producing a high-field-intensity pinch using a moving compact torus. The moving torus can serve as a very high power driver and may be used to compress a pre-established pinch field, switch on an accelerating pinch field, or may itself be reconfigured to form an intense pinch. In any case, the high energy, high energy density, and high velocity possible with an accelerated compact torus can provide extremely high power to overcome, by a number of orders of magnitude, the limitations to pinch formation described earlier. In this paper we will consider in detail pinches formed by reconfiguration of the compact torus

  1. Progress on z-pinch inertial fusion energy

    International Nuclear Information System (INIS)

    Olson, C.; Rochau, G.; Matzen, M.K.

    2005-01-01

    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. (author)

  2. 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

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

    Directory of Open Access Journals (Sweden)

    Lopez, F.

    2004-07-01

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

  4. ANALISIS FINANSIAL DAN KELEMBAGAAN RANTAI NILAI MEBEL MAHONI JEPARA

    Directory of Open Access Journals (Sweden)

    Nunung Parlinah

    2011-12-01

    Full Text Available Industri mebel umumnya termasuk dalam industri kecil dan menengah. Selain berperan dalam penerimaan devisa, bisnis di bidang mebel ini juga menciptakan lapangan kerja bagi masyarakat terutama di Kabupaten Jepara. Adanya hubungan (pemberi kepercayaan - (penerima kepercayaan yang terjadi antar aktor atau pelaku di dalam rantai berpengaruh terhadap besarnya distribusi nilai tambah yang diperoleh oleh masingmasing pelaku di sepanjang rantai nilai Tujuan dari penelitian ini adalah mengidentifikasi kelembagaan (aturan yang terjadi antar pelaku di sepanjang rantai nilai mebel mahoni Jepara dan menentukan skenario kebijakan yang dapat mendukung bagi kelestarian industri mebel Jepara. Data yang digunakan meliputi data primer dan data sekunder. Analisis data meliputi identifikasi aktor dan kelembagaan (aturan yang terjadi antar pelaku serta analisis manfaat biaya yang terdiri dari NVP, BCR dan IRR. Hasil penelitian menunjukkan bahwa (1 para pengrajin ( memproduksi mebelnya lebih didasarkan pada pesanan pembeli ( . agent principal Asymetic information yang terjadi antara pedagang kayu dan petani juga telah mengakibatkan posisi petani sebagai (2 Nilai NPV, BCRdan IRR untuk tiap pelaku berbeda-beda tetapi nilai-nilai tersebut mengindikasikan bahwa pola kemitraan yang terjadi antar pelaku dalam rantai nilai mebel mahoni saat ini sudah efektif. Skenario kebijakan yang dapat diterapkan adalah kebijakan yang bersifat insentif bagi petani hutan rakyat, peningkatan kemampuan pengrajin di bidang pemasaran; dan membangun aksi kolektif diantara pengrajin. price taker;

  5. Direction of Impurity Pinch and Auxiliary Heating in Tokamak Plasmas

    International Nuclear Information System (INIS)

    Angioni, C.; Peeters, A.G.

    2006-01-01

    A mechanism of particle pinch for trace impurities in tokamak plasmas, arising from the effect of parallel velocity fluctuations in the presence of a turbulent electrostatic potential, is identified analytically by means of a reduced fluid model and verified numerically with a gyrokinetic code for the first time. The direction of such a pinch reverses as a function of the direction of rotation of the turbulence in agreement with the impurity pinch reversal observed in some experiments when moving from dominant auxiliary ion heating to dominant auxiliary electron heating

  6. Compact reversed-field pinch reactors (CRFPR)

    International Nuclear Information System (INIS)

    Krakowski, R.A.; Miller, R.L.; Bathke, C.G.; Hagenson, R.L.; Copenhaver, C.; Werley, K.A.

    1986-01-01

    The unique confinement properties of the Reversed-Field Pinch (RFP) are exploited to examine physics and technical issues related to a compact, high-power-density fusion reactor. This resistive-coil, steady-state, toroidal device would use a dual-media power cycle driven by a fusion power core (FPC, i.e., plasma chamber, first wall, blanket, shield, and coils) with a power density and mass approaching values characteristic of pressurized-water fission rectors. A 1000-MWe(net) base case is selected from a comprehensive trade-off study to examine technological issues related to operating a high-power-density FPC. After describing the main physics and technology issues for this base-case reactor, directions for future study are suggested

  7. Pinching parameters for open (super) strings

    Science.gov (United States)

    Playle, Sam; Sciuto, Stefano

    2018-02-01

    We present an approach to the parametrization of (super) Schottky space obtained by sewing together three-punctured discs with strips. Different cubic ribbon graphs classify distinct sets of pinching parameters; we show how they are mapped onto each other. The parametrization is particularly well-suited to describing the region within (super) moduli space where open bosonic or Neveu-Schwarz string propagators become very long and thin, which dominates the IR behaviour of string theories. We show how worldsheet objects such as the Green's function converge to graph theoretic objects such as the Symanzik polynomials in the α ' → 0 limit, allowing us to see how string theory reproduces the sum over Feynman graphs. The (super) string measure takes on a simple and elegant form when expressed in terms of these parameters.

  8. Energy required to pinch a DNA plectoneme

    Science.gov (United States)

    Barde, Céline; Destainville, Nicolas; Manghi, Manoel

    2018-03-01

    DNA supercoiling plays an important role from a biological point of view. One of its consequences at the supramolecular level is the formation of DNA superhelices named plectonemes. Normally separated by a distance on the order of 10 nm, the two opposite double strands of a DNA plectoneme must be brought closer if a protein or protein complex implicated in genetic regulation is to be bound simultaneously to both strands, as if the plectoneme was locally pinched. We propose an analytic calculation of the energetic barrier, of elastic nature, required to bring closer the two loci situated on the opposed double strands. We examine how this energy barrier scales with the DNA supercoiling. For physically relevant values of elastic parameters and of supercoiling density, we show that the energy barrier is in the kBT range under physiological conditions, thus demonstrating that the limiting step to loci encounter is more likely the preceding plectoneme slithering bringing the two loci side by side.

  9. New bifocal pinch experiment SPEED 3

    International Nuclear Information System (INIS)

    Raacke, J.; Berntien, U.; Decker, G.; Kies, W.; Roewekamp, P.

    1996-01-01

    The SPEED 3 compact plasma focus device will be used as a soft x-ray source for various practical applications. It exploits a bifocal configuration with a plane insulator, very short accelerator and a hollow inner electrode. The discharge is driven by eight parallel two-stage Marx modules, capable of delivering up to 1.25 MA of current with the rise time of 0.3 s. The key parts of the device, the plasma diagnostic systems used, and the processes in the discharge are described in the paper. Framing camera pictures of a typical discharge are shown for illustration. The results of preliminary experiments are discussed, dealing almost exclusively with the discharge inaction, sheath and pinch formation. (J.U.). 1 tab., 3 figs., 2 refs

  10. New bifocal pinch experiment SPEED 3

    Energy Technology Data Exchange (ETDEWEB)

    Raacke, J; Berntien, U; Decker, G; Kies, W; Roewekamp, P [Heinrich-Heine-Univ., Duesseldorf (Germany). Inst. fuer Experimentalphysik

    1997-12-31

    The SPEED 3 compact plasma focus device will be used as a soft x-ray source for various practical applications. It exploits a bifocal configuration with a plane insulator, very short accelerator and a hollow inner electrode. The discharge is driven by eight parallel two-stage Marx modules, capable of delivering up to 1.25 MA of current with the rise time of 0.3 s. The key parts of the device, the plasma diagnostic systems used, and the processes in the discharge are described in the paper. Framing camera pictures of a typical discharge are shown for illustration. The results of preliminary experiments are discussed, dealing almost exclusively with the discharge inaction, sheath and pinch formation. (J.U.). 1 tab., 3 figs., 2 refs.

  11. Z-pinch driven fusion energy

    International Nuclear Information System (INIS)

    Slutz, Stephen A.; Olson, Craig L.; Rochau, Gary E.; Dezon, Mark S.; Peterson, P.F.; Degroot, J.S.; Jensen, N.; Miller, G.

    2000-01-01

    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. Ramp discharge in Z-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Gaber, W.H.; Beshara, A.B.; El-Bialy, A.B.; Masoud, M.M. [Plasma and Nuclear Fusion Dept., N.R.C., Atomic Energy Authority, Enshass (Egypt)

    2004-07-01

    A ramp Z-pinch discharge is designed and built in order to increase the pinch ratio and obtain a maximum contraction, and to increase the temperature. The discharge chamber is a cylindrical Pyrex tube of 25 cm long, 18.5 cm, 20 cm inner and outer diameter and two circular Aluminum plates of radius 15 cm separated by 21 cm are inserted into the tube. The tube is filled with He gas at 0.1 mbar. Two capacitor banks are used, the first bank 30 {mu}F and the second fast bank 1.3 {mu}F. The charging voltage was 8 kV for both banks. The discharge current and voltage of each bank are measured by potential divider and Rogowski coil respectively. Also the plasma inductance and resistance are obtained for each case. The plasma inductance has its peak value 300 nH at 4 {mu}s, while the plasma resistance has it minimum 8 m{omega} at the same time in the case of conventional discharge (single bank). In the case of ramp discharge, the inductance has two peaks 440 nH, 380 nH at 4 {mu}s, 9.5 {mu}s respectively, while the resistance has two minimum 4 m{omega}, 20 m{omega} at at 4 {mu}s, 9.5 {mu}s respectively. The temperature has been measure spectroscopically by using relative continuum intensity ratio method. The temperature has its peak value 38 eV at 4 {mu}s for single bank case, while it larger peak value 55 eV for ramp case. (orig.)

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

    International Nuclear Information System (INIS)

    1990-01-01

    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

  14. Nonlinear stage of a Z-pinch instability

    International Nuclear Information System (INIS)

    Garanin, S.F.; Chernyshev, Y.D.

    1987-01-01

    The nonlinear evolution of the sausage instability is analyzed for a Z-pinch with a fully developed skin effect in the current. Two-dimensional numerical calculations carried out on the sausage instability show that its occurrence leads to a stage describable by a self-similar solution when the length of the neck is fixed and the plasma compression is isentropic. At a perturbation wavelength small in comparison with the pinch radius, this stage is preceded by a stage which reduces to a nonlinear Rayleigh--Taylor instability. The dynamics of the motion of magnetic field ''bubbles'' and of plasma ''jets'' is analyzed in this case. The plasma jets emerging from the pinch do not block the pinch from the current source

  15. Plant Measurement, Sampling and Analysis for Accountancy Purposes with Particular Reference to Separation Plants at Windscale; Mesures, Echantillonnages et Analyses en Usine a des Fins Comptables, Notamment dans les Installations de Separation de Windscale; Izmereniya, vzyatie obraztsov i analizy v tselyakh ucheta na opyte ustanovki razdeleniya radioizotopov v uindskejle; Medicion, Muestreo y Analisis para Fines Contables, Especialmente en las Plantas de Separacion de Windscale

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, A. S.; Elliott, F.; Powell, R.; Swinburn, K. A. [United Kingdom Atomic Energy Authority, Windscale and Calder Works, Cumberland (United Kingdom)

    1966-02-15

    ) titrimetrie, e) dilution isotopique suivie de spectrometrie de masse, et f) spectrometrie differentielle. Ils soulignent egalement les methodes de dosage de l'uranium, notamment les suivantes: a) gravimetrie de U{sub 3}O{sub 8}. b) extraction a l ' ether suivie de gravimetrie ou de colorimetrie, c) titrimetrie, d) dilution isotopique suivie de spectrometrie de masse, et e) determination de l'enrichissement par spectrometrie de masse ou spectrographie des emissions accompagnees d'un deplacement des raies. Pour toutes les methodes comptables, on utilise des etalons pour assurer le controle de la qualite et faire ressortir toute inexactitude qu'il est necessaire de corriger. Les auteurs indiquent la precision de chaque methode et enumerent les methodes effectivement utilisees dans la nouvelle usine de separation. (author) [Spanish] Todas las cifras destinadas a la contabilidad de materiales especiales corresponden por lo menos a uno de los tres parametros siguientes: medicion en la planta, muestreo y analisis. Para las mediciones en la planta conviene emplear la pesada siempre que sea posible; por ejemplo, la cantidad de plutonio que entra en la nueva planta de separacion de Windscale se calcula a base del peso de las barras de uranio. Los autores exponen los metodos de medicion de volumenes: a) 'pneumercator', y b) empleo de cesio radiactivo como indicador, y evaluan la exactitud y precision de cada uno de esos metodos. El muestreo de soluciones en un proceso intermitente se efectua con tubos evacuados despues de homogeneizar la solucion. Para las corrientes 'continuas' , que requieren mucha exactitud, se ha ideado un dispositivo de muestreo continuo que se emplea a la entrada de la nueva planta de separacion. En Windscale, el metodo normal de muestreo consiste en taladrar lingotes metalicos; para otros solidos se sigue la practica de homogeneizar todo lo posible el material antes de tomar la muestra (para el oxido de plutonio, por ejemplo, se emplea una mezcladora conica en Y

  16. ANALISIS IMPOR BERAS DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Ratih Kumala Sari

    2014-10-01

    Full Text Available Abstrak ___________________________________________________________________ Salah satu kebijakan pemerintah untuk memenuhi kebutuhan beras yaitu dengan menggenjot produksi beras dalam negeri. Namun dengan semakin meningkatnya jumlah penduduk akan meningkatkan permintaan terhadap beras dan upaya peningkatan produktivitas dalam negeri tidak dapat memenuhi kebutuhan beras dalam negeri. Sehingga untuk menutupi kekurangan tersebut pemerintah mengambil keputusan untuk melakukan impor beras dari negara lain. Akan tetapi pada kenyataannya impor beras dilakukan ketika data statistik menunjukkan bahwa Indonesia sedang mengalami surplus beras. Penelitian ini bertujuan untuk mengetahui faktor-faktor apa saja yang mempengaruhi impor beras di Indonesia. Metode analisis yang digunakan adalah analisis regresi linier berganda dengan model Error Correction Model (ECM. Berdasarkan hasil penelitian disimpulkan bahwa secara parsial maupun secara bersama-sama produksi beras, konsumsi beras, harga beras dalam negeri dan nilai tukar rupiah terhadap dollar AS berpengaruh dan signifikan terhadap impor beras di Indonesia. Abstract ___________________________________________________________________ One of the government’s policy to fulfill the need of rice is to boost the domestic production. However, by increasing the population, the demand of rice will also increase and the effort of increasing the domestic productivity cannot supply domestic rice need. So, to cover the shortage the government make decision to import rice from other countries. Yet, in fact importing rice is occurred when the statistical data showed that the supply of rice in Indonesia is surplus. The purpose of this research is necessary to study the factors which influence the import of rice in Indonesia. The analysis method used is multiple linear regression analysis model with Error Correction Model (ECM. Based on the research proven that partially or jointly the production, the consumption, the

  17. Determining the resistance of X-pinch plasma

    International Nuclear Information System (INIS)

    Zhao Shen; Zhu Xin-Lei; Zhang Ran; Luo Hai-Yun; Zou Xiao-Bing; Wang Xin-Xin; Xue Chuang; Ning Cheng; Ding Ning; Shu Xiao-Jian

    2013-01-01

    The current and the voltage of an X-pinch were measured. The inductance of the X-pinch was assumed to be a constant and estimated by the calculation of the magnetic field based on the well-known Biot—Savart's Law. The voltage of the inductance was calculated with L · di/dt and subtracted from the measured voltage of the X-pinch. Then, the resistance of the X-pinch was determined and the following results were obtained. At the start of the current flow the resistance of the exploding wires is several tens of Ohms, one order of magnitude, higher than the metallic resistance of the wires at room temperature, and then it falls quickly to about 1 Ω, which reflects the physical processes occurring in the electrically exploding wires, i.e., a current transition from the highly resistive wire core to the highly conductive plasma. It was shown that the inductive contribution to the voltage of the X-pinch is less than the resistive contribution. For the wires we used, the wires' material and diameter have no strong influence on the resistance of the X-pinch, which may be explained by the fact that the current flows through the plasma rather than through the metallic wire itself. As a result, the current is almost equally divided between two parallel X-pinches even though the diameter and material of the wires used for these two X-pinches are significantly different. (physics of gases, plasmas, and electric discharges)

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

    International Nuclear Information System (INIS)

    Lööf, Jasmine; Rosell, Johan; Bratthäll, Charlotte; Doré, Siv; Starkhammar, Hans; Zhang, Hong; Sun, Xiao-Feng

    2011-01-01

    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

  19. Experimental study of the neck formation in an X pinch

    International Nuclear Information System (INIS)

    Artyomov, A P; Chaikovsky, S A; Fedunin, A V; Labetskaya, N A; Rousskikh, A G; Zhigalin, A S; Oreshkin, V I

    2014-01-01

    X-pinch experiments have been performed on a compact 250 kA, 180 ns pulsed power generator specially designed for this purpose at the Institute of High Current Electronics (Tomsk, Russia). The X pinches were composed of two molybdenum wires of diameter 25 μm making an angle of 36° with the z-axis. The X-pinch dynamics was recorded with a 3 ns exposure time using an HSFC Pro four-frame camera. Axial plasma jets propagating toward both the anode and the cathode were observed. The jets became noticeable within 10 ns after the onset of current flow, which approximately corresponded to the time at which the electrical explosion of the X-pinch wires occurred. The velocity of the anode-directed jet reached 10 7 cm/s, which was about 1.5 times the velocity of the cathode-directed jet. These high jet velocities are inconsistent with the plasma temperature resulting from the wire explosion. Hence, these jets seem to develop due to implosion of the light plasma layer stripped by magnetic forces from the wire surface, and the increase in their velocities is perhaps due to cumulative effects taking place at the X-pinch axis. The X-pinch neck formed as a rule above the initial wire cross point (closer to the anode). In this region, the plasma diameter gradually increased with time and then drastically decreased 10-15 ns prior to the x-ray pulse. Immediately before the x-ray pulse, in the (250-300 μm long) plasma neck, a lower scale constriction developed, forming a h ot spot . It has been confirmed that the anode-directed plasma jet could take some part of the X-pinch wire current because of the evident jet pinching in the anode region. This process seems to determine the neck length

  20. Pinch grafting for chronic venous leg ulcers in general practice

    OpenAIRE

    Steele, Keith

    1985-01-01

    Twenty-five patients with chronic venous leg ulcers were treated in general practice by pinch grafting. Fifteen of the ulcers (60%) were completely healed one year after grafting. Prior to grafting 19 patients (76%) complained of daily pain in the ulcer. These patients experienced complete relief from pain after grafting. Pinch grafting is a simple, safe and effective therapy when applied in a domiciliary environment.

  1. 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.

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

    OpenAIRE

    Alfredo Torres-Fernández; Manuel Díaz-de los Ríos; Marlen Ramil-Mesa; Indira Pérez-Bermúdez

    2013-01-01

    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 de...

  3. ANALISIS PERANCANGAN BUSINESS INTELLIGENCE BERBASIS SAAS CLOUD COMPUTING

    Directory of Open Access Journals (Sweden)

    I Gede Adnyana

    2014-05-01

    Full Text Available Persaingan bisnis yang ketat, mendorong setiap perusahaan menyusun strategi bisnis agar dapat bertahan dari para pesaing. Penyusunan strategi bisnis mutlak memerlukan informasi yang tepat dan akurat, pengolahan hingga analisis data yang menghasilkan informasi yang tepat dan akurat menjadi proses yang sangat penting. Business Intelligence (BI menawarkan solusi bisnis untuk menganalisis data dan memungkinkan suatu perusahaan untuk mengambil keputusan untuk meningkatkan keuntungan dan kinerja bisnis. Namun, BI mahal untuk diimplementasikan, memerlukan biaya pemeliharaan yang tidak sedikit dan infrastruktur yang kuat. Hal ini mendorong perusahaan mengurangi biaya tetapi masih memiliki teknologi yang tepat untuk memungkinkan mereka untuk membuat keputusan, mengidentifikasi peluang dan proaktif mengidentifikasi risiko yang dapat mempengaruhi bisnis. Konsep Software as a Service (SaaS Cloud Computing dapat menjawab tantangan yang dihadapi BI. Sebelum merancang BI berbasis SaaS perlu diketahui parameter-parameter evaluasi hingga kelebihan dan kekurangannya.

  4. Pinch-off Scaling Law of Soap Bubbles

    Science.gov (United States)

    Davidson, John; Ryu, Sangjin

    2014-11-01

    Three common interfacial phenomena that occur daily are liquid drops in gas, gas bubbles in liquid and thin-film bubbles. One aspect that has been studied for these phenomena is the formation or pinch-off of the drop/bubble from the liquid/gas threads. In contrast to the formation of liquid drops in gas and gas bubbles in liquid, thin-film bubble pinch-off has not been well documented. Having thin-film interfaces may alter the pinch-off process due to the limiting factor of the film thickness. We observed the pinch-off of one common thin-film bubble, soap bubbles, in order to characterize its pinch-off behavior. We achieved this by constructing an experimental model replicating the process of a human producing soap bubbles. Using high-speed videography and image processing, we determined that the minimal neck radius scaled with the time left till pinch-off, and that the scaling law exponent was 2/3, similar to that of liquid drops in gas.

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

    International Nuclear Information System (INIS)

    Lassing, H.W.

    1989-01-01

    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

  6. Sausage mode of a high density Z-pinch

    International Nuclear Information System (INIS)

    Pereira, N.; Rostoker, N.

    1983-01-01

    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

  7. The ZaP Flow Z-Pinch Project

    International Nuclear Information System (INIS)

    Shumlak, U.; Nelson, B. A.

    2005-01-01

    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 0.1kV A , 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

  8. 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.

  9. 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.

  10. Finite-Larmor-radius effects on z-pinch stability

    Science.gov (United States)

    Scheffel, Jan; Faghihi, Mostafa

    1989-06-01

    The effect of finite Larmor radius (FLR) on the stability of m = 1 small-axial-wavelength kinks in a z-pinch with purely poloidal magnetic field is investigated. We use the incompressible FLR MHD model; a collisionless fluid model that consistently includes the relevant FLR terms due to ion gyroviscosity, Hall effect and electron diamagnetism. With FLR terms absent, the Kadomtsev criterion of ideal MHD, 2r dp/dr + m2B2/μ0 ≥ 0 predicts instability for internal modes unless the current density is singular at the centre of the pinch. The same result is obtained in the present model, with FLR terms absent. When the FLR terms are included, a normal-mode analysis of the linearized equations yields the following results. Marginally unstable (ideal) modes are stabilized by gyroviscosity. The Hall term has a damping (but not absolutely stabilizing) effect - in agreement with earlier work. On specifying a constant current and particle density equilibrium, the effect of electron diamagnetism vanishes. For a z-pinch with parameters relevant to the EXTRAP experiment, the m = 1 modes are then fully stabilized over the crosssection for wavelengths λ/a ≤ 1, where a denotes the pinch radius. As a general z-pinch result a critical line-density limit Nmax = 5 × 1018 m-1 is found, above which gyroviscous stabilization near the plasma boundary becomes insufficient. This limit corresponds to about five Larmor radii along the pinch radius. The result holds for wavelengths close to, or smaller than, the pinch radius and for realistic equilibrium profiles. This limit is far below the required limit for a reactor with contained alpha particles, which is in excess of 1020 m-1.

  11. Finite-Larmor-radius effects on z-pinch stability

    Energy Technology Data Exchange (ETDEWEB)

    Scheffel, J.; Faghihi, M. (Royal Inst. of Tech., Stockholm (Sweden))

    1989-06-01

    The effect of finite Larmor radius (FLR) on the stability of m = 1 small-axial-wavelength kinks in a z-pinch with purely poloidal magnetic field is investigated. The incompressible FLR MHD model is used; a collisionless fluid model that consistently includes the relevant FLR terms due to ion gyroviscosity, Hall effect and electron diamagnetism. With FLR terms absent, the Kadomtsev criterion of ideal MHD, 2rdp/dr+m{sup 2}B{sup 2}/{mu}{sub 0}{ge}0 predicts instability for internal modes unless the current density is singular at the centre of the pinch. The same result is obtained in the present model, with FLR terms absent. When the LFR terms are included, a normal-mode analysis of the linearized equations yields the following results. Marginally unstable (ideal) modes are stabilized by gyroviscosity. The Hall term has a damping (but no absolutely stabilizing) effect - in agreement with earlier work. On specifying a constant current and particle density equilibrium, the effect of electron diamagnetism vanishes. For a z-pinch with parameters relevant to the EXTRAP experiment, the m = 1 modes are then fully stabilized over the cross-section for wavelengths {lambda}/{alpha}{le}1, where {alpha} denotes the pinch radius. As a general z-pinch result a critical line-density limit ''N''{sub max}=5x10{sup 18}m{sup -1} is found, above which gyroviscous stabilization near the plasma boundary becomes insufficient. This limit corresponds to about five Larmor radii along the pinch radius. The result holds for wavelengths close to, or smaller than, the pinch radius and for realistic equilibrium profiles. This limit is far below the required limit for a reactor with contained alpha particles, which is in excess of 10{sup 20} m{sup -1}. (author).

  12. Finite-Larmor-radius effects on z-pinch stability

    International Nuclear Information System (INIS)

    Scheffel, J.; Faghihi, M.

    1989-01-01

    The effect of finite Larmor radius (FLR) on the stability of m = 1 small-axial-wavelength kinks in a z-pinch with purely poloidal magnetic field is investigated. The incompressible FLR MHD model is used; a collisionless fluid model that consistently includes the relevant FLR terms due to ion gyroviscosity, Hall effect and electron diamagnetism. With FLR terms absent, the Kadomtsev criterion of ideal MHD, 2rdp/dr+m 2 B 2 /μ 0 ≥0 predicts instability for internal modes unless the current density is singular at the centre of the pinch. The same result is obtained in the present model, with FLR terms absent. When the LFR terms are included, a normal-mode analysis of the linearized equations yields the following results. Marginally unstable (ideal) modes are stabilized by gyroviscosity. The Hall term has a damping (but no absolutely stabilizing) effect - in agreement with earlier work. On specifying a constant current and particle density equilibrium, the effect of electron diamagnetism vanishes. For a z-pinch with parameters relevant to the EXTRAP experiment, the m = 1 modes are then fully stabilized over the cross-section for wavelengths λ/α≤1, where α denotes the pinch radius. As a general z-pinch result a critical line-density limit ''N'' max =5x10 18 m -1 is found, above which gyroviscous stabilization near the plasma boundary becomes insufficient. This limit corresponds to about five Larmor radii along the pinch radius. The result holds for wavelengths close to, or smaller than, the pinch radius and for realistic equilibrium profiles. This limit is far below the required limit for a reactor with contained alpha particles, which is in excess of 10 20 m -1 . (author)

  13. Reversed field pinch reactor study 3

    International Nuclear Information System (INIS)

    Hollis, A.A.; Mitchell, J.T.D.

    1977-12-01

    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)

  14. Reversed-Field Pinch Reactor (RFPR) concept

    International Nuclear Information System (INIS)

    Hagenson, R.L.; Krakowski, R.A.; Cort, G.E.

    1979-08-01

    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 Li 2 O 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 Li 2 O 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

  15. Scaling laws for spherical pinch experiments

    International Nuclear Information System (INIS)

    Singh, D.P.; Palleschi, V.; Vaselli, M.

    1991-01-01

    In spherical pinch (SP) experiments, the plasma heated at the center of a cell to reach ignition temperature is confined by imploding shock waves for a time long enough to satisfy the Lawson criterion for plasma fusion. In earlier theoretical studies, the expansion of the central plasma either is neglected or is assumed to be radially uniform. The energy is considered to be deposited instantaneously at the center of the cell and the nonlinear heat conduction equation is solved to study the temporal evolution of the central plasma. Incorporating the ignition condition for the average temperature of the expanding fireball, and its confinement by imploding convergent shock waves, which may be fired from the periphery of the cell with some time delay, the scaling laws for satisfying the Lawson criterion are investigated in detail. The relevant calculations indicate that the cumulative effects of the convergent shock waves in the vicinity of the center of the cell play an important role in these scaling laws. (author)

  16. Pinch technique for Schwinger-Dyson equations

    International Nuclear Information System (INIS)

    Binosi, Daniele; Papavassiliou, Joannis

    2007-01-01

    In the context of scalar QED we derive the pinch technique self-energies and vertices directly from the Schwinger-Dyson equations. After reviewing the perturbative construction, we discuss in detail the general methodology and the basic field-theoretic ingredients necessary for the completion of this task. The construction requires the simultaneous treatment of the equations governing the scalar self-energy and the fundamental interaction vertices. The resulting non-trivial rearrangement of terms generates dynamically the Schwinger-Dyson equations for the corresponding Green's functions of the background field method. The proof relies on the extensive use of the all-order Ward-identities satisfied by the full vertices of the theory and by the one-particle-irreducible kernels appearing in the usual skeleton expansion. The Ward identities for these latter quantities are derived formally, and several subtleties related to the structure of the multiparticle kernels are addressed. The general strategy for the generalization of the method in a non-Abelian context is briefly outlined, and some of the technical difficulties are discussed

  17. Pinch Me - I'm Fusing

    International Nuclear Information System (INIS)

    Derzon, Mark S.

    2000-01-01

    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. 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

  18. Reversed-field pinch fusion reactor

    International Nuclear Information System (INIS)

    Hagenson, R.L.; Krakowski, R.A.

    1980-01-01

    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 Li 2 O 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

  19. Magnetic field compression using pinch-plasma

    International Nuclear Information System (INIS)

    Koyama, K.; Tanimoto, M.; Matsumoto, Y.; Veno, I.

    1987-01-01

    In a previous report, the method for ultra-high magnetic field compression by using the pinchplasma was discussed. It is summarized as follows. The experiment is performed with the Mather-type plasma focus device tau/sub 1/4/ = 2 μs, I=880 kA at V=20 kV). An initial DC magnetic field is fed by an electromagnet embedded in the inner electrode. The axial component of the magnetic field diverges from the maximum field of 1 kG on the surface of the inner electrode. The density profile deduced from a Mach-Zehnder interferogram with a 2-ns N/sub 2/-laser shows a density dip lasting for 30 ns along the axes. Using the measured density of 8 x 10/sup 18/ cm/sup -3/, the temperature of 1.5 keV and the pressure balance relation, the magnitude of the trapped magnetic field is estimated to be 1.0 MG. The magnitude of the compressed magnetic field is also measured by Faraday rotation in a single-mode quartz fiber and a magnetic pickup soil. A protective polyethylene tube (3-mm o.d.) is used along the central axis through the inner electrode and the discharge chamber. The peak value of the compressed field range from 150 to 190 kG. No signal of the magnetic field appears up to the instance of the maximum pinch

  20. Compact reversed-field pinch reactors (CRFPR)

    International Nuclear Information System (INIS)

    Krakowski, R.A.; Hagenson, R.L.; Schnurr, N.M.; Copenhaver, C.; Bathke, C.G.; Miller, R.L.; Embrechts, M.J.

    1986-01-01

    The unique confinement properties of the poloidal-field-dominated Reversed-Field Pinch (RFP) are exploited to examine physics and technical issues related to a compact high-power-density fusion reactor. This resistive-coil, steady-state, toroidal device would use a dual-media (i.e., two separate coolants) power cycle that would be driven by a fusion power core (FPC, i.e., plasma chamber, first wall, blanket, shield, and coils) having a power density and mass approaching pressurized-water-fission reactor values. A 1000-MWe(net) base case is selected from a comprehensive trade-off study to examine technological issues related to operating a high-power-density FPC. A general rationale outlining the need for improved fusion concepts is given, followed by a description of the RFP principle, a detailed systems and trade-off analysis, and a conceptual FPC design for the ∝ 20-MW/m 2 (neutrons) compact RFP reactor, CRFPR(20). Key FPC components are quantified, and full power-balance, thermal, and mechanical FPC integrations are given. (orig.)

  1. 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

  2. Scaling of X pinches from 1 MA to 6 MA

    International Nuclear Information System (INIS)

    Bland, Simon Nicholas; McBride, Ryan D.; Wenger, David Franklin; Sinars, Daniel Brian; Chittenden, Jeremy Paul; Pikuz, Sergei A.; Harding, Eric; Jennings, Christopher A.; Ampleford, David J.; Yu, Edmund P.; Cuneo, Michael Edward; Shelkovenko, Tatiana A.; Hansen, Stephanie B.

    2010-01-01

    This final report for Project 117863 summarizes progress made toward understanding how X-pinch load designs scale to high currents. The X-pinch load geometry was conceived in 1982 as a method to study the formation and properties of bright x-ray spots in z-pinch plasmas. X-pinch plasmas driven by 0.2 MA currents were found to have source sizes of 1 micron, temperatures >1 keV, lifetimes of 10-100 ps, and densities >0.1 times solid density. These conditions are believed to result from the direct magnetic compression of matter. Physical models that capture the behavior of 0.2 MA X pinches predict more extreme parameters at currents >1 MA. This project developed load designs for up to 6 MA on the SATURN facility and attempted to measure the resulting plasma parameters. Source sizes of 5-8 microns were observed in some cases along with evidence for high temperatures (several keV) and short time durations (<500 ps).

  3. Hybrid Z-Θ Pinches with fused capacitor banks

    International Nuclear Information System (INIS)

    Grandey, R.; Gersten, M.; Loter, N.; Rauch, J.; Rostoker, N.; Thompson, W.; Ware, K.

    1987-01-01

    The Hybrid Z-Θ Pinch circuit equations in the thin shell model were reexamined to see what advantages can be obtained by using a fused, high-energy (>--1MJ) bank driver. The DNA ACE facility at MLI utilizes a 36 μF capacitor band which can be charged to 120 kV to provide 250 kJ of stored energy. This configuration appears to be very appropriate to test the performance of a hybrid-stabilized fused-bank driven pinch. The circuit analyses suggest that the energy transfer efficiency from the bank to a pinched plasma can be increased from less than 1%, for a nonfused bank, to about 10% for a fused configuration. In the applicable region of parameter space, the Hybrid Pinch does not increase the efficiency of energy transfer into the plasma over that obtainable from a Z-pinch. The additional stability may allow larger initial radii to be used with concomitant improved coupling into radiation above 1 keV

  4. Acoustic bubble enhanced pinched flow fractionation for microparticle separation

    International Nuclear Information System (INIS)

    Zhou, Ran; Wang, Cheng

    2015-01-01

    Pinched flow fractionation is a simple method for separating micron-sized particles by size, but has certain intrinsic limitations, e.g. requirement of a pinched segment similar to particle size and limited separation distance. In this paper, we developed an acoustic bubble enhanced pinched flow fractionation (PFF) method for microparticle separation. The proposed technique utilized microbubble streaming flows to overcome the limitations of conventional PFF. Our device has demonstrated separation of different sized microparticles (diameters 10 and 2 μm) with a larger pinched segment (60 μm) and at different buffer/particle solution flow rate ratios (5–25). The separation distances between particles are larger (as much as twice as large) than those achieved with conventional PFF. In addition, the separation position and distance can be adjusted by changing the driving voltage. The robust performance is due to the unique features of the flow field inside the pinched segment. We investigated several factors, including flow rate ratio, total flow rate and driving voltage, that affect the separation performance. (paper)

  5. Analisis Value Chain Di Industri Otomotif

    OpenAIRE

    Hendri, Hendri

    2017-01-01

    Penelitian ini untuk menganalisis industri otomotif. Tujuan dari penelitian ini adalah untuk menganalisis dan mengetahui aktivitas dan kondisi internal proses industri manufaktur dengan menggunakan value chain guna masukan dimasa akan datang bagi industri otomotif secara khusus. Value Chain merupakan rantai nilai yang dapat mengetahui kekuatan Perusahaan, keuntungan dan kesuksesan dari rantai aktivitas dalam Perusahaan atau industri manufaktur.Metode analisis menggunakan Statistika Deskript...

  6. 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

  7. Experimental studies of an Extrap Z-Pinch

    International Nuclear Information System (INIS)

    Drake, J.R.

    1983-01-01

    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 10 18 m - 1 , are consistent in magnitude and scaling with the Bennet relation. (Author)

  8. Self-similar oscillations of the Extrap pinch

    International Nuclear Information System (INIS)

    Tendler, M.

    1987-11-01

    The method of the dynamic stabilization is invoked to explain the enhanced stability of a Z-pinch in EXTRAP configuration. The oscillatory motion is assumed to be forced on EXTRAP due to self-similar oscillations of a Z-pinch. Using a scaling for the net energy loss with plasma density and temperature typical for divertor configurations, a new analytic, self-similar solution of the fluid equations is presented. Strongly unharmonic oscillations of the plasma parameters in the pinch arise. These results are used in a discussion on the stability of EXTRAP, considered as a system with a time dependent internal magnetic field. The effect of the dynamic stabilization is considered by taking estimates. (author)

  9. Mechanism of hot spots formation in magnetic Z-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Kubes, P; Kravarik, J [Ceske Vysoke Uceni Technicke, Prague (Czech Republic). Fakulta Elektrotechnicka; Kolacek, K; Krejci, A [Akademie Ved Ceske Republiky, Prague (Czech Republic). Ustav Fyziky Plazmatu; Paduch, M; Tomaszewski, K [Inst. of Plasma Physics and Laser Microfusion, Warsaw (Poland)

    1997-12-31

    The evolution of neon implosion of low energy discharge (4 kJ, 40 kV, 150 kA, 1.1 {mu}s) was studied using X-ray, schlieren and high speed electrooptical visible gated Quadro camera diagnostics. The geometry, the helical structure of pinched column, two steps of pinching and X-ray emission were studied. The diameters, electron density and temperature of the hot spots were determined. The hypothesis of axial component of magnetic field generation, of helical shape of magnetic and electric field lines, of the possibility of the release of magnetic energy and of the acceleration of the keV electrons and ions due to voltage induction during the second pinching of the column are discussed. (author). 3 figs., 5 refs.

  10. Magnetostatic Analysis of a Pinch Mode Magnetorheological Valve

    Directory of Open Access Journals (Sweden)

    Gołdasz Janusz

    2017-09-01

    Full Text Available The study deals with the pinch mode of magnetorheological (MR fluids’ operation and its application in MR valves. By applying the principle in MR valves a highly non-uniform magnetic field can be generated in flow channels in such a way to solidify the portion of the material that is the nearest to the flow channel’s walls. This is in contrary to well-known MR flow mode valves. The authors investigate a basic pinch mode valve in several fundamental configurations, and then examine their magnetic circuits through magnetostatic finite-element (FE analysis. Flux density contour maps are revealed and basic performance figures calculated and analysed. The FE analysis results yield confidence in that the performance of MR pinch mode devices can be effectively controlled through electromagnetic means.

  11. ANALISIS KESELAMATAN TERMOHIDROLIK BULK SHIELDING REAKTOR KARTINI

    Directory of Open Access Journals (Sweden)

    Azizul Khakim

    2015-10-01

    Full Text Available ABSTRAK ANALISIS KESELAMATAN TERMOHIDROLIK BULK SHIELDING REAKTOR KARTINI. Bulk shielding merupakan fasilitas yang terintegrasi dengan reaktor Kartini yang berfungsi sebagai penyimpanan sementara bahan bakar bekas. Fasilitas ini merupakan fasilitas yang termasuk dalam struktur, sistem dan komponen (SSK yang penting bagi keselamatan. Salah satu fungsi keselamatan dari sistem penanganan dan penyimpanan bahan bakar adalah mencegah kecelakaan kekritisan yang tak terkendali dan membatasi naiknya temperatur bahan bakar. Analisis keselamatan paling kurang harus mencakup analisis keselamatan dari sisi neutronik dan termo hidrolik Bulk shielding. Analisis termo hidrolik ditujukan untuk memastikan perpindahan panas dan proses pendinginan bahan bakar bekas berjalan baik dan tidak terjadi akumulasi panas yang mengancam integritas bahan bakar. Code tervalidasi PARET/ANL digunakan untuk analisis pendinginan dengan mode konveksi alam. Hasil perhitungan menunjukkan bahwa mode pendinginan konvekasi alam cukup memadai dalam mendinginkan panas sisa tanpa mengakibatkan kenaikan temperatur bahan bakar yang signifikan. Kata kunci: Bulk shielding, bahan bakar bekas, konveksi alam, PARET.   ABSTRACT THERMAL HYDRAULIC SAFETY ANALYSIS OF BULK SHIELDING KARTINI REACTOR. Bulk shielding is an integrated facility to Kartini reactor which is used for temporary spent fuels storage. The facility is one of the structures, systems and components (SSCs important to safety. Among the safety functions of fuel handling and storage are to prevent any uncontrolable criticality accidents and to limit the fuel temperature increase. Safety analyses should, at least, cover neutronic and thermal hydraulic calculations of the bulk shielding. Thermal hydraulic analyses were intended to ensure that heat removal and the process of the spent fuels cooling takes place adequately and no heat accumulation that challenges the fuel integrity. Validated code, PARET/ANL was used for analysing the

  12. Computer modeling of a small neon gas-puff pinch

    International Nuclear Information System (INIS)

    Ullschmied, J.

    1996-01-01

    The macroscopic dynamics of a cylindrical gas-puff pinch and conditions of radiation plasma collapse are studied by using a one-dimensional ('mechanical') computer model. Besides the Joule plasma heating, compressional heating, magnetic field freezing in a plasma and recombination losses, also the real temperature- and density-dependences of radiation plasma loss are taken into account. The results of calculations are compared with experimental data taken from a small neon-puff z-pinch experiment operated at the Institute of Plasma Physics in Prague. (author). 7 figs., 11 refs

  13. Pinched hysteresis behavior in a PID-controlled resistor

    Directory of Open Access Journals (Sweden)

    M.A. Carrasco-Aguilar

    2018-06-01

    Full Text Available A current-controlled grounded resistor that exhibits a frequency-dependent pinched hysteresis loop is described. A mathematical model describing this behavior is derived and validated numerically, which has the form of a Proportional Integral-Derivative (PID controller. The proposed topology is build by using AD844 commercially available active device configured as second-generation current conveyor and experimental tests are compared with numerical simulations, showing a good agreement among them. Moreover, the proposed PID-controlled resistor can be reconfigured in order to be used in future applications such as programmable analog circuits. Keyword: Pinched hysteresis, Current conveyors, Nonlinear resistor, Proportional-Integral-Derivative Controller

  14. Seeded perturbations in wire array Z-Pinches

    International Nuclear Information System (INIS)

    Robinson, Allen Conrad; Fedin, Dmitry; Kantsyrev, Victor Leonidovich; Wunsch, Scott Edward; Oliver, Bryan Velten; Lebedev, Sergey V.; Coverdale, Christine Anne; Ouart, Nicholas D.; LePell, Paul David; Safronova, Alla S.; Shrestha, I.; McKenney, John Lee; Ampleford, David J.; Rapley, J.; Bott, S.C.; Palmer, J.B.A.; Sotnikov, Vladimir Isaakovich; Bland, Simon Nicholas; Ivanov, Vladimir V.; Chittenden, Jeremy Paul; Jones, B.; Garasi, Christopher Joseph; Hall, Gareth Neville; Yilmaz, M. Faith; Mehlhorn, Thomas Alan; Deeney, Christopher; Pokala, S.; Nalajala, V.

    2005-01-01

    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.

  15. Mechanism of neutron generation in Z-pinches

    International Nuclear Information System (INIS)

    Vikhrev, V.V.

    1986-01-01

    The review of experimental and theoretical investigations in a mechanism of neutron generation in Z-pinches is presented. Special attention is paid to the thermonuclear mechanism of neutron generation occuring due to the formation of high-temperature plasma regions in Z-pinch sausage-type instabilities. This mechanism is shown to be predominant in charges with the neutron yield more than 10 9 per a charge. Experimental data, which are considered to be contradicting to thermonuclear nature of neutron radiation, are explained

  16. Numerical investigations of Z-pinch plasma instabilities

    International Nuclear Information System (INIS)

    Duan Yaoyong; Guo Yonghui; Wang Wensheng; Qiu Aici

    2004-01-01

    A two-dimensional, radiation magneto-hydrodynamics model is applied to the simulation of Z-pinch plasma sausage instability. Different implosion mechanisms in the cases of the existence and the non-existence of instability are analyzed, and the effects of various initial density perturbation levels on the x-ray power and energy are investigated. Numerical results show that x-ray energy output is not susceptive to sausage instabilities in a certain extent but x-ray power versus time is evidently dependent on the instabilities. In addition, this paper also studies the effects of numerical treatment of extreme low density in Z-pinch simulations on numerical results

  17. MHD turbulence models for the reversed field pinch

    International Nuclear Information System (INIS)

    Gimblett, C.G.; Watkins, M.L.

    1976-01-01

    A kinematic model which describes the effect of isotropic, non-mirror symmetric turbulence on a mean magnetic field is used to examine the temporal behaviour of magnetic field in high beta pinch experiments. Solutions to the model can indicate the formation of a steady-state, force-free configuration that corresponds to the state of lowest magnetic energy and the reversal of the toroidal magnetic field at the plasma boundary in accordance with experimental observations on toroidal pinches such as ZETA and HBTX. This model neglects both the dynamic interaction between fluid and field and the associated anisotropy. These effects are examined in a further model. (author)

  18. Simplified scaling model for the THETA-pinch

    Science.gov (United States)

    Ewing, K. J.; Thomson, D. B.

    1982-02-01

    A simple ID scaing model for the fast Theta pinch was developed and written as a code that would be flexible, inexpensive in computer time, and readily available for use with the Los Alamos explosive-driven high magnetic field program. The simplified model uses three successive separate stages: (1) a snowplow-like radial implosion, (2) an idealized resistive annihilation of reverse bias field, and (3) an adiabatic compression stage of a Beta = 1 plasma for which ideal pressure balance is assumed to hold. The code uses one adjustable fitting constant whose value was first determined by comparison with results from the Los Alamos Scylla III, Scyllacita, and Scylla IA Theta pinches.

  19. Architecture of petawatt-class z-pinch accelerators

    International Nuclear Information System (INIS)

    Stygar, William A.; Mazarakis, Michael Gerrassimos; Cuneo, Michael Edward; Leeper, Ramon Joe; Ives, H.C.; Headley, D.I.; Wagoner, Tim C.; Porter, John Larry Jr.

    2006-01-01

    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 10 6 capacitors and 5 x 10 5 200-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

  20. Energy transfer efficiency measurements in a theta-pinch

    International Nuclear Information System (INIS)

    Cavalcanti, G.H.; Luna, F.R.T.; Trigueiros, A.G.

    1993-01-01

    An increase in energy transfer efficiency of the capacitor bank to the plasma was obtained when the electrical system of a theta-pinch was changed so that the ratio of total inductance to coil inductance was switched of 1/6 to 1/2. A further increase about 20% was obtained for 16/1 ratio. The measurements were made through the current discharge decay, and the spectral analysis of the emitted light from theta-pinch shows a correspondent efficiency increase. (author)

  1. Explosive instabilities of reaction-diffusion equations including pinch effects

    International Nuclear Information System (INIS)

    Wilhelmsson, H.

    1992-01-01

    Particular solutions of reaction-diffusion equations for temperature are obtained for explosively unstable situations. As a result of the interplay between inertial, diffusion, pinch and source processes certain 'bell-shaped' distributions may grow explosively in time with preserved shape of the spatial distribution. The effect of the pinch, which requires a density inhomogeneity, is found to diminish the effect of diffusion, or inversely to support the inertial and source processes in creating the explosion. The results may be described in terms of elliptic integrals or. more simply, by means of expansions in the spatial coordinate. An application is the temperature evolution of a burning fusion plasma. (au) (18 refs.)

  2. Cryogenic deuterium Z-pinch and wire array Z-pinch studies at Imperial College

    International Nuclear Information System (INIS)

    Haines, M.G.; Aliaga-Rossel, R.; Beg, N.F.

    2001-01-01

    Z-pinch experiments using cryogenic deuterium fibre loads have been carried out on the MAGPIE generator at currents up to 1.4MA. M=0 instabilities in the corona caused plasma expansion and disruption before the plasma could enter the collisionless Large ion Larmor radius regime. For the last 12 months we have studied Aluminium wire array implosions using laser probing, optical streaks and gated X-ray images. Plasma from the wires in accelerated to the axis as radial plasma streams with uncorrelated m=0 instabilities superimposed. Later in the discharge a global Rayleigh-Taylor (R-T) instability develops. Single and double aluminium and tungsten wire shots were conducted at 150kA. 2-D and 3-D simulations and a heuristic model of wire arrays will be presented along with theories on the combined MHD/R-T instability and sheared axial flow generation by large ion Larmor radius effects. (author)

  3. Cryogenic deuterium Z-pinch and wire array Z-pinch studies at imperial college

    International Nuclear Information System (INIS)

    Haines, M.G.; Aliaga-Rossel, R.; Beg, F.N.

    1999-01-01

    Z-pinch experiments using cryogenic deuterium fibre loads have been carried out on the MAGPIE generator at currents up to 1.4MA. M=0 instabilities in the corona caused plasma expansion and disruption before the plasma could enter the collisionless Large ion Larmor radius regime. For the last 12 months we have studied Aluminium wire array implosions using laser probing, optical streaks and gated X-ray images. Plasma from the wires in accelerated to the axis as radial plasma streams with uncorrelated m=0 instabilities superimposed. Later in the discharge a global Rayleigh-Taylor (R-T) instability develops. Single and double aluminium and tungsten wire shots were conducted at 150kA. 2-D and 3-D simulations and a heuristic model of wire arrays will be presented along with theories on the combined MHD/R-T instability and sheared axial flow generation by large ion Larmor radius effects. (author)

  4. 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.

  5. Current redistribution and generation of kinetic energy in the stagnated Z pinch.

    Science.gov (United States)

    Ivanov, V V; Anderson, A A; Papp, D; Astanovitskiy, A L; Talbot, B R; Chittenden, J P; Niasse, N

    2013-07-01

    The structure of magnetic fields was investigated in stagnated wire-array Z pinches using a Faraday rotation diagnostic at the wavelength of 266 nm. The distribution of current in the pinch and trailing material was reconstructed. A significant part of current can switch from the main pinch to the trailing plasma preheated by x-ray radiation of the pinch. Secondary implosions of trailing plasma generate kinetic energy and provide enhanced heating and radiation of plasma at stagnation. Hot spots in wire-array Z pinches also provide enhanced radiation of the Z pinch. A collapse of a single hot spot radiates 1%-3% of x-ray energy of the Z pinch with a total contribution of hot spots of 10%-30%.

  6. ANALISIS RESPON PEMANGKU KEPENTINGAN DI DAERAH TERHADAP KEBIJAKAN HUTAN TANAMAN RAKYAT

    Directory of Open Access Journals (Sweden)

    Tuti Herawati

    2014-08-01

    Full Text Available Tujuan penelitian adalah menganalisis respon para pemangku kepentingan di daerah terhadap kebijakan Hutan Tanaman Rakyat. Penelitian menggunakan metode pendekatan kuantifikasi data kualitatif. Lokasi penelitian ditentukan secara sengaja dengan pertimbangan tingginya potensi pengembangan kegiatan HTR, yaitu di Provinsi Kalimantan Selatan dan Riau. Hasil penelitian menunjukkan bahwa masyarakat di Kalimantan Selatan, khususnya mereka yang telah terlibat dalam pengembangan tanaman kehutanan memiliki minat yang tinggi untuk menjadi peserta program HTR. Sedangkan masyarakat di Riau kurang berminat terhadap program penanaman tanaman kehutanan, disebabkan adanya pengalaman buruk di masa sebelumnya. Para pemangku kepentingan di tingkat kabupaten yang terdiri dari pihak pemerintah daerah dan swasta menyambut baik program tersebut, dan mendukung terselenggaranya program sebagai upaya peningkatan kesejahteraan masyarakat sekitar hutan. Berdasarkan hasil analisis stakeholder diketahui bahwa terdapat sejumlah pemangku kepentingan di daerah yang memiliki posisi dan pengaruh penting untuk keberhasilan program. Hal ini berimplikasi bahwa para pengambil kebijakan di tingkat pusat harus mempertimbangkan aspirasi mereka untuk mewujudkan keberhasilan program HTR.

  7. Toroidal equilibrium in an iron-core reversed field pinch

    International Nuclear Information System (INIS)

    Miller, G.

    1984-04-01

    An analytical theory of toroidal equilibrium in the ZT-40M reversed field pinch is obtained, including effects of iron cores and resistive shell. The iron cores alter the form of the equilibrium condition and cause the equilibrium to be unstable on the shell resistive time scale

  8. More efficient mushroom canning through pinch and exergy analysis

    NARCIS (Netherlands)

    Paudel, Ekaraj; Sman, van der Ruud G.M.; Westerik, Nieke; Awasthi, Ashutosh; Dewi, Belinda P.C.; Boom, Remko M.

    2017-01-01

    Conventional production of canned mushrooms involves multiple processing steps as vacuum hydration, blanching, sterilization, etc. that are intensive in energy and water usage. We analyzed the current mushroom processing technique plus three alternative scenarios via pinch and exergy analysis.

  9. Pinch analysis for bioethanol production process from lignocellulosic biomass

    International Nuclear Information System (INIS)

    Fujimoto, S.; Yanagida, T.; Nakaiwa, M.; Tatsumi, H.; Minowa, T.

    2011-01-01

    Bioethanol produced from carbon neutral and renewable biomass resources is an attractive process for the mitigation of greenhouse gases from vehicle exhaust. This study investigated energy utilization during bioethanol production from lignocellulose while avoiding competition with food production from corn and considering the potential mitigation of greenhouse gases. Process design and simulations were performed for bioethanol production using concentrated sulfuric acid. Mass and heat balances were obtained by process simulations, and the heat recovery ratio was determined by pinch analysis. An energy saving of 38% was achieved. However, energy supply and demand were not effectively utilized in the temperature range from 95 to 100 o C. Therefore, a heat pump was used to improve the temperature range of efficient energy supply and demand. Results showed that the energy required for the process could be supplied by heat released during the process. Additionally, the power required was supplied by surplus power generated during the process. Thus, pinch analysis was used to improve the energy efficiency of the process. - Highlights: → Effective energy utilization of bioethanol production was studied by using pinch analysis. → It was found that energy was not effectively utilized in the temperature range from 95 to 100 o C. → Use of a heat pump was considered to improve the ineffective utilization. → Then, remarkable energy savings could be achieved by it. → Pinch analysis effectively improved the energy efficiency of the bioethanol production.

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

    International Nuclear Information System (INIS)

    Lins, G.

    1980-01-01

    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)

  11. Diffusion-driven steady states of the Z-pinch

    International Nuclear Information System (INIS)

    Lehnert, B.

    1988-01-01

    Steady states of a Z-pinch where no electric field is imposed along the pinch axis by external means are investigated. In this case, diffusion-driven states become possible when imposed volume sources of particles and heat drive a radial diffusion velocity that, in its turn, generates the electric plasma current. The particle sources can be from pellet injection or a neutral gas blanket, and the heat sources provided by thermonuclear reactions or auxiliary heating. The present analysis and associated kinetic considerations indicate that steady diffusion-driven operation should become possible for certain classes of plasma profiles, without running into singularity problems at the pinch axis. Such operation leads to higher axial currents in a Z-pinch without an axial magnetic field than in a tokamaklike case under similar plasma conditions. The technical difficulty in realizing a volume distribution of particle sinks introduces certain constraints on the plasma and current profiles. This fact has to be taken into account in a stability analysis. Neoclassical or anomalous diffusion will increase the diffusion velocity of the plasma but is not expected to affect the main physical features of the present results

  12. Investigation of the preionization in the high voltage belt pinch

    International Nuclear Information System (INIS)

    Protz, R.

    1975-07-01

    The production of plasmas is investigated which are necessary for shock wave experiments. By optimization of a two-stage pre-ionization, an ignition can be initiated down to 0.5 m of Hg deuterium. The plasma is diagnosed with a 90 0 multichannel laser light scattering in the belt-pinch. (GG/LH) [de

  13. Overview of quasi single helicity experiments in reversed field pinches

    International Nuclear Information System (INIS)

    Martin, P.; Marrelli, L.; Spizzo, G.

    2003-01-01

    We report the results of an experimental and theoretical project dedicated to the study of Quasi Single Helicity Reversed Field Pinch plasmas. The project has involved several RFP devices and numerical codes. It appears that QSH spectra are a feature common to all the experiments. (author)

  14. Flow effects on the stability of z-pinches

    International Nuclear Information System (INIS)

    Shumlak, U.; Hartman, C.W.

    1996-01-01

    The effect of an axial flow on the m = 1 kink instability in z-pinches is studied numerically by reducing the linearized ideal MHD equations to a one-dimensional eigenvalue equation for the radial displacement. The derivation of the displacement equation for equilibria with axial flows will be presented. A diffuse z-pinch equilibrium is chosen that is made marginally stable to the m = 0 sausage mode by tailoring the pressure profile. The principle result reveals that a sheared axial flow does stabilize the kink mode when the shear exceeds a threshold value. Additionally, the m = 0 sausage mode is driven from marginal stability into the stable regime which suggests that the equilibrium pressure profile control can be relaxed. Fast z-pinches such as liner implosions are plagued by the Rayleigh-Taylor instability which destroys the liner and disrupts the current path before the liner arrives on axis. A sheared axial flow in a liner may quench the Rayleigh-Taylor instability in the same way that it quenches MHD instabilities in a diffuse z-pinch. Simulation results will be presented showing the effect of a sheared axial flow on the Rayleigh-Taylor instability in a fast liner implosion

  15. Migration of plasma points in the Z-pinch

    International Nuclear Information System (INIS)

    Afonin, V.I.

    1995-01-01

    The paper deals with the generation of a spontaneous magnetic field in Z-pinch sausage-type instability plasma and the effect of magnetic field on sausage-type instability movement. The presented evaluations of spontaneous magnetic fields and their role in the migration of plasma points are in a satisfactory agreement with the experimental data. 8 refs

  16. Liquid conductor model of instabilities in a pinched discharge

    Energy Technology Data Exchange (ETDEWEB)

    Dattnery, A; Lehnert, B [Dept. of Electronics, Royal Institute of Technology, Stockholm (Sweden); Lundquist, S [Swedish State Power Board (Sweden)

    1958-07-01

    The pinched gas discharge experiments seem to have been handicapped by the great speed with which the instability develops as well as by the light coming from impurities instead of the main body of pinched gas. In the present work a liquid conductor is used in order to study the structure of the instabilities. The study of a pinch was made with and without the axial magnetic field. In cases with a magnetic field, the currents and fields were chosen so as to give a longitudinal magnetic field equal to or three times the azimuthal field at the boundary of the mercury stream. The study of the results shows that in the case without an external magnetic field there is a similarity between the behavior of the pinch in a stream of mercury and in an ionized gas column. The stabilizing action of the surface tension is small and the instabilities develop easily. The case with an external magnetic field is more complicated. The magnetic lines of force are not frozen into the medium; they can 'escape' from the medium. In this case the magnetic field has no stabilizing effect. The influence of conducting walls around the mercury column will be studied in forthcoming experiments.

  17. Draws on a relativistic pinch with a longitudinal magnetic field

    International Nuclear Information System (INIS)

    Trubnikov, B.A.

    1991-01-01

    The problems of draws on a relativistic pinch with longitudinal magnetic field are discussed. The absence of collisions promoting the energy exchange between different degrees of particle freedom is assumed. The calculations are conducted using the ideal relativistic anisotropic magnetic hydrodynamics equations. The spectrum of particles accelerated in the draws, is determined

  18. Linear Transformer Drivers for Z-pinch Based Propulsion

    Science.gov (United States)

    Adams, Robert; Seidler, William; Giddens, Patrick; Fabisinski, Leo; Cassibry, Jason

    2017-01-01

    The MSFC/UAH team has been developing of a novel power management and distribution system called a Linear Transformer Driver (LTD). LTD's hold the promise of dramatically reducing the required mass to drive a z-pinch by replacing the capacitor banks which constitute half the mass of the entire system. The MSFC?UAH tea, is developing this technology in hope of integrating it with the Pulsed Fission Fusion (PuFF) propulsion concept. High-Voltage pulsed power systems used for Z-Pinch experimentation have in the past largely been based on Marx Generators. Marx generators deliver the voltage and current required for the Z-Pinch, but suffer from two significant drawbacks when applied to a flight system: they are very massive, consisting of high-voltage capacitor banks insulated in oil-filled tanks and they do not lend themselves to rapid pulsing. The overall goal of Phase 2 is to demonstrate the construction of a higher voltage stack from a number of cavities each of the design proven in Phase 1 and to characterize and understand the techniques for designing the stack. The overall goal of Phase 3 is to demonstrate the feasibility of constructing a higher energy cavity from a number of smaller LTD stacks, to characterize and understand the way in which the constituent stacks combine, and to extend this demonstration LTD to serve as the basis for a 64 kJ pulse generator for Z-Pinch experiments.

  19. Finite Larmor radius effects on Z-pinch stability

    International Nuclear Information System (INIS)

    Scheffel, J.; Faghihi, M.

    1987-10-01

    The effect of finite Larmor radius (FLR) on the stability of m=1 small axial wavelength kinks in a z-pinch with purely poloidal magnetic field is investigated. We use the Incompressible FLR MHD model; a collisionless fluid model which consistently includes the relevant FLR terms due to ion gyroviscosity, Hall effect and electron diamagnetism. With FLR terms absent, the Kadomtsev criterion of ideal MHD 2rdp/dr+m 2 B 2 /μ 0 >=0 predicts instability for internal modes unless the current density becomes singular at the centre of the pinch. The same result is obtained in the present model, with FLR terms absent. When the FLR terms are included, a normal mode analysis of the linearized equations yields the following results. Marginally unstable (ideal) modes are stabilized by gyroviscosity. The Hall terms have a damping, however not stabilizing, effect, in agreement with earlier work. Specifying a constant current and particle density equilibrium, the effect of electron diamagnetism vanishes. For a z-pinch with parameters relevant to the EXTRAP experiment, the m=1 modes are then fully stabilized over the cross-section for wavelengths λ/a max =3-5x10 18 m -1 is found, above which gyroviscous stabilization near the plasma boundary becomes insufficient. The result holds for wavelengths close to, or smaller than, the pinch radius and for realistic equilibrium profiles. This limit is far below the required limit for a reactor with contained alpha particles, which is in excess of 10 20 m -1 . (authors)

  20. Collapse of Z-pinch necks for inertial fusion

    International Nuclear Information System (INIS)

    Yan'kov, V.V.

    1989-01-01

    The ignition is possible under the condition of collapring z-pinch neck up to the diameter 10 -4 cm. The current pulse with duration 10 -7 s and 10 7 A must be applied to a cylinder of condensed D-T mixture in order to obtain the parameter ρr≥0.4 g/cm 2 . 22 refs

  1. 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

  2. On finite larmor radius stabilization of Z-pinches

    International Nuclear Information System (INIS)

    Hellsten, T.

    1982-12-01

    Finite Larmor radius stabilization of Z-pinches is discussed. Stability criteria can be derived for a class of equilibria having constant mass and current density. The internal modes can be stabilized provided the line density not exceed a critical value of the order of 10 18 ions/m. (Author)

  3. Radiative collapse of a Bennett-relaxed z-pinch

    International Nuclear Information System (INIS)

    Turner, L.

    1989-01-01

    The global evolution of a z-pinch has been studied with the assumption of a relaxed state consisting of ions and electrons, each in a rigidly drifting isothermal Maxwellian distribution. This speculative approach has the pragmatic feature of possessing phenomenologically useful global parameters such as drift velocity and temperature that vary in accordance with global physical quantities such as energy and entropy. The plasma gains energy from a time-dependent electric field by means of Poynting's vector. Coulomb collisions between electrons and ions is calculated with a Fokker-Planck treatment analogous to that used by Dreicer to calculate runaways. For a variety of initial conditions and time-independent applied electric fields, the pinch evolution always culminates in a time-independent (attractor) state whose current is the Pease-Braginskii current and whose final radius is proportional to (line density)/sup 3/4//(electric field)/sup 1/2/. Before the final state is attained, the pinch may bounce toward and away from a highly collapsed state. For the case of a Bennett pinch, the classical limit of the resistivity is attained when the line density is much greater than 4πm/sub e//e 2 μ/sub o/; i.e., 3.55 /times/ 10 14 m/sup /minus/1/. 6 refs., 2 figs

  4. Instability study during implosion in the Tupa Theta-Pinch

    International Nuclear Information System (INIS)

    Kayama, M.E.; Boeckelmann, H.K.

    1986-01-01

    The importance of instabilities which occur during plasma heating in a Theta Pinch, in the implosion phase, is analysed. The plasma diagnostic was done by ultrafast photography and diamagnetic probe. The implosion time and the current layer thickness were calculated using a hybrid code for plasma simulation. The theoretical data were compared with the experimental ones. (M.C.K.) [pt

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

    International Nuclear Information System (INIS)

    Hirano, K.

    1987-05-01

    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)

  6. Electrical insulators for the theta-pinch fusion reactor

    International Nuclear Information System (INIS)

    Clinard, F.W. Jr.

    1976-01-01

    The five major applications for electrical insulators in the Reference Theta Pinch Reactor are as follows: (1) first-wall insulator, (2) blanket intersegment insulator, (3) graphite encapsulating insulator, (4) implosion coil insulator, and (5) compression coil insulator. Insulator design proposals and some preliminary test results are given for each application

  7. The physics of reversed-field pinch profile sustainment

    International Nuclear Information System (INIS)

    Moses, R.W.

    1985-01-01

    A description of the Reversed-Field Pinch (RFP) is given. There is experimental evidence that indicates that an RFP dynamo effect sustains field reversal in steady state. Three sustainment mechanisms are reviewed: the MHD model, the tangled discharge model, and the kinetic dynamo model. The relationship of these models to each another is discussed briefly

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

    International Nuclear Information System (INIS)

    Eriksson, G.

    1987-05-01

    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)

  9. Architecture of petawatt-class z-pinch accelerators

    Directory of Open Access Journals (Sweden)

    W. A. Stygar

    2007-03-01

    Full Text Available 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   μs Marx generators, which are a mature technology but which necessitate significant pulse compression to achieve the short pulses (≪1   μs required to drive z pinches. The other is powered by linear transformer drivers (LTDs, which are less mature but produce much shorter pulses than conventional Marxes. Consequently, an LTD-driven accelerator promises to be (at a given pinch current and implosion time more efficient and reliable. The Marx-driven accelerator produces a peak electrical power of 500 TW and includes the following components: (i 300 Marx generators that comprise a total of 1.8×10^{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

  10. Pinch modes in the SPEED2 plasma focus

    International Nuclear Information System (INIS)

    Kies, W.; Decker, G.; Berntien, U.; Glushkov, D.A.; Sidelnikov, Yu.V.; Koshelev, K.N.; Simanovskij, D.M.; Bobashev, S.V.

    2001-01-01

    Deuterium discharges in the SPEED2 plasma focus (80 kJ, 200 kV, 2 MA, 400 ns) have been found unexpectedly stable within the operational regime as a neutron source. Only at higher filling pressures (above 6 mbar) sometimes m=0 instabilities appeared in the pinch column, especially in discharges of lower efficiency (moderate dynamics and neutron yield). Enhancing the electromagnetic radiation by doping these discharges with heavy gases (e.g. neon, argon) distinctly two pinch modes are produced, the micropinch mode (MPM) or the stable column mode (SCM), with a transition regime where the initial SCM is followed by the MPM. Micropinches are local radiative collapses initiated by m=0 instabilities of low-energy-density pinch plasmas. These instabilities and the successive micropinches can be suppressed by kinetic deuterons produced during dynamical compression of high-energy-density deuterium plasma sheaths. Depending on the relaxation of this fast deuteron component the pinch column can be stabilized for several tens of nanoseconds. While the short-lived (appr.1 ns) micropinches erratically appear as point-like successive flashes along the pinch axis with temperatures about 1 keV and about solid density the reproducible SCM, optimized with respect to the compression ratio, forms a powerful linear radiation source of temperatures and densities similar to the MPM. The SCM needs powerful (fast) drivers in order to use the kinetic ion stabilization, but not necessarily MA currents as available from the SPEED2 driver. This opens the possibility to establish the SCM also in compact experiments like SPEED3 (8 kJ, 80 kV, 0.8 MA, 300 ns) or even SPEED4 (2 kJ, 40 kV 250 kA, 300 ns). (author)

  11. Analisis Kinerja Local Area Network Menggunakan Router.

    OpenAIRE

    Hutahaean, Yosua

    2012-01-01

    Perangkat internetworking menawarkan komunikasi di antara segmen Local Area Network (LAN). Ada empat tipe utama perangkat internetworking ini: repeater, bridge, router, dan gateway. Perangkat ini dibedakan atas dasar system lapisan Open System Interconnection (OSI) yang digunakan, berfungsi sebagai media komunikasi dari LAN ke LAN. Pada Tugas Akhir ini penulis tertarik untuk membahas analisis kinerja Local Area Network (LAN) menggunakan Router yang menggunakan sistem antrian M/M/1 dimana j...

  12. EKSLUSI DAN INKLUSI PADA RUBRIK METROPOLITAN HARIAN KOMPAS: ANALISIS WACANA KRITIS BERDASARKAN SUDUT PANDANG THEO VAN LEEUWEN

    Directory of Open Access Journals (Sweden)

    Harry Andheska

    2015-10-01

    Full Text Available Penggunaan teori kritis sebagai alat pengkajian dalam penelitian ini disebabkan oleh adanya persoalan tentang penumpang kereta rel listrik (KRL yang sering melanggar aturan dengan menaiki atap kereta tersebut. Penelitian ini pada dasarnya lebih menekankan titik perhatiannya pada sosok penumpang KRL sebagai sosok yang senantiasa termajinalkan dalam kehidupan sosial. Kajian ini merupakan pendekatan kualitatif dengan metode analisis isi. Kajian ini juga terbatas hanya pada satu teks berita yang dimuat dalam satu rubrik metropolitan pada haian Kompas. Model analisis wacana yang digunakan adalah model Theo Van Leuween dengan tujuan untuk mendeteksi dan meneliti bagaimana para penumpang yang duduk di atap KRL dimarjinalkan posisinya dalam suatu wacana. Hasil penelitian ditemukan bahwa terdapat dua jenis eksklusi yang dilakukan, yakni pasivasi dan nominalisasi; sedangkan inklusi ada tiga jenis, yakni diferensiasi, abstraksi, dan identifikasi. Keterbatasan dalam kajian ini disebabkan karena faktor kajian yang hanya terfokus pada satu teks berita.

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

    International Nuclear Information System (INIS)

    Vikhrev, V.V.; Ivanov, V.V.; Rozanova, G.A.

    1989-01-01

    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

  14. Kinetic simulation of neutron production in a deuterium z-pinch

    International Nuclear Information System (INIS)

    Mostrom, C.; Stygar, William A.; Thoma, Carsten; Welch, Dale Robert; Clark, R.E.; Leeper, Ramon Joe; Rose, David V.

    2010-01-01

    We have found computationally that, at sufficiently high currents, half of the neutrons produced by a deuterium z pinch are thermonuclear in origin. Early experiments below 1-MA current found that essentially all of the neutrons produced by a deuterium pinch are not thermonuclear, but are initiated by an instability that creates beam-target neutrons. Many subsequent authors have supported this result while others have claimed that pinch neutrons are thermonuclear. To resolve this issue, we have conducted fully kinetic, collisional, and electromagnetic simulations of the complete time evolution of a deuterium pinch. We find that at 1-MA pinch currents, most of the neutrons are, indeed, beam-target in origin. At much higher current, half of the neutrons are thermonuclear and half are beam-target driven by instabilities that produce a power law fall off in the ion energy distribution function at large energy. The implications for fusion energy production with such pinches are discussed.

  15. Proposal for the ZT-40 reversed-field Z-pinch experiment

    International Nuclear Information System (INIS)

    Baker, D.A.; Machalek, M.D.

    1977-08-01

    A next-generation, toroidal, reversed-field Z-pinch experiment to be constructed at LASL is proposed. On the basis of encouraging ZT-I and ZT-S experimental results, a larger device with a 40-cm bore and a 114-cm major radius is proposed, to extend the confinement time by about an order of magnitude. The new experiment will explore the physics of programming reversed-field pinches in a size range unexplored by previous reversed-field pinch experiments. Model reversed-field pinch reactor calculations show that, if stability is assumed, small fusion reactors are possible if the pinch current density is high. A basic aim will be to delineate the plasma and current density ranges in which stable reversed-field pinches can be produced. Improved vacuum techniques will be used to overcome the radiation losses that probably kept electron temperatures low in the earlier, smaller experiments

  16. D-D fusion experiments using fast z pinches

    International Nuclear Information System (INIS)

    Spielman, R.B.; Baldwin, G.T.; Cooper, G.

    1994-01-01

    The development of high current (I > 10 MA) drivers provides us with a new tool for the study of neutron-producing plasmas in the thermal regime. The imploded deuterium mass (or collisionality) increases as I 2 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 10 12 D-D neutrons. These experiments were designed to explore the physics of neutron-generating plasmas in a z-pinch geometry. Specifically, we 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

  17. X pinch a point x-ray source

    International Nuclear Information System (INIS)

    Garg, A.B.; Rout, R.K.; Shyam, A.; Srinivasan, M.

    1993-01-01

    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

  18. The Rayleigh-Taylor instability in the spherical pinch

    International Nuclear Information System (INIS)

    Chen, H.B.; Hilko, B.; Panarella, E.

    1994-01-01

    The spherical pinch (SP) concept is an outgrowth of the inertial confinement model (ICF). Unlike the ICF where instabilities, especially the Rayleigh-Taylor instability, have been studied extensively, the instability study of the spherical pinch has just begun. The Raleigh-Taylor instability is investigated for the first time in the SP in the present work. By using the simple condition for the Rayleigh-Taylor instability ∇p · ∇p < O (density and pressure gradients have opposite direction), we have qualitatively identified the regions for development of instabilities in the SP. It is found that the explosion phase (central discharge) is stable and instabilities take place in the imploding phase. However, the growth rate for the instability is not in exponential form, and the appearance of the Rayleigh-Taylor instability does not prevent the main shock wave from converging to the center of the sphere

  19. Characterisation of Plasma Filled Rod Pinch electron beam diode operation

    Science.gov (United States)

    MacDonald, James; Bland, Simon; Chittenden, Jeremy

    2016-10-01

    The plasma filled rod pinch diode (aka PFRP) offers a small radiographic spot size and a high brightness source. It operates in a very similar to plasma opening switches and dense plasma focus devices - with a plasma prefill, supplied via a number of simple coaxial plasma guns, being snowploughed along a thin rod cathode, before detaching at the end. The aim of this study is to model the PFRP and understand the factors that affect its performance, potentially improving future output. Given the dependence on the PFRP on the prefill, we are making detailed measurements of the density (1015-1018 cm-3), velocity, ionisation and temperature of the plasma emitted from a plasma gun/set of plasma guns. This will then be used to provide initial conditions to the Gorgon 3D MHD code, and the dynamics of the entire rod pinch process studied.

  20. Production of ion beam by conical pinched electron beam diode

    International Nuclear Information System (INIS)

    Matsukawa, Y.; Nakagawa, Y.

    1982-01-01

    Some properties of the ion beam produced by pinched electron beam diode having conical shape electrodes and organic insulator anode was studied. Ion energy is about 200keV and the peak diode current is about 30 kA. At 11cm from the diode apex, not the geometrical focus point, concentrated ion beam was obtained. Its density is more than 500A/cm 2 . The mean ion current density within the radius of 1.6cm around the axis from conical diode is two or three times that from an usual pinched electron beam diode with flat parallel electrodes of same dimension and impedance under the same conditions. (author)

  1. On the equilibrium of a linear Extrap pinch

    International Nuclear Information System (INIS)

    Lehnert, B.

    1982-01-01

    The equilibrium is studied of a pinched linear plasma column of 'Extrap' type which is confined in a purely transverse magnetic field, partly arising from currents in a set of external conductor rods being introduced for stabilizing purposes. The axial and transverse losses are separated in a simplified theoretical model for which stability is assumed as a working hypothesis and anomalous transport as well as impurity radiation are neglected. Then, the reduction of the axial heat transport by the magnetic field will have a substantial effect on the over-all heat balance, thus leading to high temperatures at large axial lengths of the plasma column. Conditions near ignition should become possible at technically realistic linear dimensions and pinch currents. (orig.)

  2. A heuristic model of the wire array z-pinch

    International Nuclear Information System (INIS)

    Haines, M.G.

    1998-01-01

    Recent experimental results at the Sandia National Laboratory have shown that the X-ray power increases as the number of wires n employed is increased, with a sharper increase in power when the wire gap is below a critical value. This paper proposes a model that can not only explain these phenomena, but also shows how the initial perturbations that lead to the Rayleigh-Taylor instability scale as n -1/2 . The model predicts the shell thickness at merger of the expanding separate wires which will mainly determine the final pinch radius. The largest amplitude Rayleigh-Taylor mode at the pinch time is also found, in reasonable agreement with experiment

  3. The belt-shaped screw-pinch reactor

    International Nuclear Information System (INIS)

    Bustraan, M.; Klippel, H.Th.; Veringa, H.J.; Verschuur, K.A.; Lievense, K.

    1981-12-01

    The belt-shaped screw pinch is a pulsed toroidal plasma with an elongated cross-section. Force-free currents in an outer plasma envelope of low density allow beta to rise to high values in the order of 50%. This is a potential possibility to develop an economically attractive reactor. The physical requirements of its realization are described: formation, heating and ignition of a very small amount of the fuel to be burnt in one pulse by the fields generated by normal or superconducting coils. Then follows injection of the greater part of the fuel by D-T pellets and consequent plasma heating and expansion by nuclear reactions without undue disturbing of the plasma current configuration. Technical requirements include an insulating first wall and fast rising magnetic fields produced by superconducting coils. This reactor system is compared with the tokamak and the reversed-field pinch system

  4. Seeded perturbations in wire array z-pinches

    International Nuclear Information System (INIS)

    Robinson, Allen Conrad; Kantsyrev, Victor Leonidovich; Wunsch, Scott Edward; Oliver, Bryan Velten; Lebedev, Sergey V.; Safronova, Alla S.; Maxwell, J.; McKenney, John Lee; Ampleford, David J.; Rapley, J.; Bott, S.C.; Palmer, J.B.A.; Bland, Simon Nicholas; Jones, Brent Manley; Chittenden, Jeremy Paul; Garasi, Christopher Joseph; Hall, Gareth Neville; Mehlhorn, Thomas Alan; Deeney, Christopher

    2004-01-01

    The impact of 3D structure on wire array z-pinch dynamics is a topic of current interest, and has been studied by the controlled seeding of wire perturbations. First, Al wires were etched at Sandia, creating 20% radial perturbations with variable axial wavelength. Observations of magnetic bubble formation in the etched regions during experiments on the MAGPIE accelerator are discussed and compared to 3D MHD modeling. Second, thin NaF coatings of 1 mm axial extent were deposited on Al wires and fielded on the Zebra accelerator. Little or no axial transport of the NaF spectroscopic dopant was observed in spatially resolved K-shell spectra, which places constraints on particle diffusivity in dense z-pinch plasmas. Finally, technology development for seeding perturbations is discussed

  5. On the dynamics of cylindrical z-pinch

    International Nuclear Information System (INIS)

    Solov'ev, L.S.

    1984-01-01

    The stationary configurations of cylindrical plasma flow in the framework of two-liquid relativistic electromagnetic gas dynamics (REMG)) and nonlinear radial oscillations of the plasma cylinder with longitudinal current in the framework of classical monoliquid MGD are considered. It is shown that at sufficiently high conductivity Z-pinch is stable relative to one-dimensional radial perturbations and its motion represents respectively nonlinear radial oscillations. In case of a rather low conductivity or low particle concentration there is in cross section a stability also in relation to the development of sausage type instability. The performed investigations of cylindrical equilibrium and radial oscillations give a qualitative representation on plasma behaviour in Z-pinch at the initial stage of it compression and expansion as well as on motion in an average plane of the developing sausage type instability

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

    International Nuclear Information System (INIS)

    Kalantar, D.H.; Hammer, D.A.; Qi, N.; Mittal, K.C.

    1990-01-01

    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

  7. Recent studies of Reversed-Field Pinch reactors

    International Nuclear Information System (INIS)

    Hagenson, R.L.; Krakowski, R.A.

    1981-01-01

    The reactor prognoses of a class of confinement scheme that relies primarily on self-fields induced by axial currents flowing within a plasma column are presented. The primary focus has been placed on the toroidal Reversed-Field Pinch (RFP). At the limit of very large current densities is the gas-embedded Dense Z-Pinch (DZP), a small-radius, linear device. Past conventional RFP reactor designs are reviewed. The extention of these conventional RFP reactors to DD advanced-fuel operation is described. The implications are summarized of operating higher-density, compact RFPs as reactors, wherein the current density rather than physical dimensions are scaled. Lastly, the application of very high current densities supported in a sub-millimeter linear current channel, as embodied in the DZP reactor, is reviewed

  8. D-D fusion experiments using fast Z pinches

    International Nuclear Information System (INIS)

    Spielman, R.B.; Baldwin, G.T.; Cooper, G.

    1998-03-01

    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 I 2 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 10 12 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

  9. Tungsten Z-Pinch Long Implosions on the Saturn Generator

    International Nuclear Information System (INIS)

    DOUGLAS, MELISSA R.; DEENEY, Christopher; SPIELMAN, RICK B.; COVERDALE, CHRISTINE A.; RODERICK, N.F.; HAINES, M.G.

    1999-01-01

    Recent success on the Saturn and Z accelerators at Sandia National Laboratories have demonstrated the ability to scale z-pinch parameters to increasingly larger current pulsed power facilities. Next generation machines will require even larger currents (>20 MA), placing further demands on pulsed power technology. To this end, experiments have been carried out on Saturn operating in a long pulse mode, investigating the potential of lower voltages and longer implosion times while still maintaining pinch fidelity. High wire number, 25 mm diameter tungsten arrays were imploded with implosion times ranging from 130 to 240 ns. The results were comparable to those observed in the Saturn short pulse mode, with risetimes on the order of 4.5 to 6.5 ns. Experimental data will be presented, along with two dimensional radiation magnetohydrodynamic simulations used to explain and reproduce the experiment

  10. The stability of Z-pinches with equilibrium flows

    International Nuclear Information System (INIS)

    Howell, D.F.

    1999-01-01

    According to Ideal Magnetohydrodynamic (MHD) theory the Z-pinch is an inherently unstable magnetic configuration. However it is possible that there exist regimes of operation whereby the predicted instabilities may be reduced or even eliminated. We must look to effects normally ignored in the Ideal MHD model in order to predict such regimes. In this thesis various non-ideal effects will be studied, namely the inclusion of equilibrium flow and finite Larmor radius effects. Astrophysical jets, for example those seen to be emitted from active galactic nuclei, are seen to persist for a greater time than suggested by Ideal MHD before the onset of instabilities. It is postulated that one of the contributing factors to this enhanced stability is the presence of a sheared axial flow. In this thesis we study the stability properties of the Z-pinch where flow is present in the equilibrium. It is found that a sheared axial flow generally has a stabilising effect, the degree of which is determined by the equilibrium and flow profiles, but that absolute stability cannot be achieved due to the onset of the Kelvin-Helmholtz instability. The effect of adding rotation has also been studied. It is found that adding rotation changes the equilibrium density profiles from the static case, and that it always has a destabilising effect. Another postulated method of stabilising the Z-pinch is by increasing the ratio of the ion Larmor radius to the pinch radius, and it is seen to have a stabilising effect for some equilibria in the collisionless regime. In this thesis we study the effects of increasing the Larmor radius in the collisional regime using the Hall fluid model. It is found that for free boundary modes the stability properties are unchanged for experimentally realistic values of the Larmor radius, but for fixed boundary modes a small stabilising effect is noted for some equilibria. (author)

  11. Necessary stability condition for field-reversed theta pinches

    International Nuclear Information System (INIS)

    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 2 is positive, where kappa is the curvature. A similar criterion is derived for linear systems and is applied to a noncircular z-pinch

  12. Primarily Experimental Results for a W Wire Array Z Pinch

    International Nuclear Information System (INIS)

    Kuai Bin; Aici, Qiu; Wang Liangping; Zeng Zhengzhong; Wang Wensheng; Cong Peitian; Gai Tongyang; Wei Fuli; Guo Ning; Zhang Zhong

    2006-01-01

    Primarily experimental results are given for a W wire array Z pinch imploded with up to 2 MA in 100 ns on a Qiangguang-I pulsed power generator. The configuration and parameters of the generator, the W wire array load assembly and the diagnostic system for the experiment are described. The total X-ray energy has been obtained with a averaged power of X-ray radiation of 1.28 TW

  13. Global properties of ohmically heated reversed-field pinches

    International Nuclear Information System (INIS)

    Gerwin, R.A.

    The simultaneous requirements of power balance and pressure balance have been considered. The treatment generalizes the Pease-Braginskii pinch current limit by including toroidal magnetic field, anomalous resistivity, nonradiative losses, and time-dependent fields. The rise of the temperature to a state of power balance proves to be amenable to a very simple and unified description. Finally, the practical parameter windows implied by the joint action of power balance and pressure balance are displayed

  14. Self-similar oscillations of a Z pinch

    International Nuclear Information System (INIS)

    Felber, F.S.

    1982-01-01

    A new analytic, self-similar solution of the equations of ideal magnetohydrodynamics describes cylindrically symmetric plasmas conducting constant current. The solution indicates that an adiabatic Z pinch oscillates radially with a period typically of the order of a few acoustic transit times. A stability analysis, which shows the growth rate of the sausage instability to be a saturating function of wavenumber, suggests that the oscillations are observable

  15. Prospects for fusion applications of reversed-field pinches

    International Nuclear Information System (INIS)

    Bathke, C.G.; Krakowski, R.A.; Hagenson, R.L.

    1985-01-01

    The applicability of the Reversed-Field Pinch (RFP) as a source of fusion neutrons for use in developing key fusion nuclear technologies is examined. This Fusion Test Facility (FTF) would emphasize high neutron wall loading, small plasma volume, low fusion and driver powers, and steady-state operation. Both parametric tradeoffs based on present-day physics understanding and a conceptual design based on an approx.1-MW/m 2 (neutron) driven operation are reported. 10 refs

  16. BATCH PROCESS INTEGRATION OF APPLYING TECHNOLOGY OF ACID CARMINIC PINCH

    OpenAIRE

    Erazo E., Raymundo; Cárdenas R., Jorge L.; Woolcott H., Juan C.

    2014-01-01

    This work was developed in order to implement the PINCH technology integration batch process for carminic acid. The method used consisted of the application of the concepts of bottle necks total process (OPB) together with part-time models (TAM) and time fractionated! (TSM). The drying operation is identified as the rate limiting step of the process identifying it as an OPB plant capacity. The extraction yield was 95% w / p carminic acid with an energy savings of approximately 60% of the...

  17. Electron beam generation in z-pinch discharges

    Energy Technology Data Exchange (ETDEWEB)

    Vikhrev, V.V.; Baronova, E.O. [Kurchatov Inst., Moscow (Russian Federation). Russian Research Center

    1997-12-31

    Numerical modelling of the process of electron beam generation in z-pinch discharges are presented. The proposed model represents the electron beam generation under turbulent plasma conditions. Strong current distribution inhomogeneity in the plasma column and the zigzag drift current motion through the plasma have accounted for the adequate generation process investigation. Electron beam is generated near the maximum of compression and it is not related with the current break effect. (author)

  18. A reversed-field theta-pinch plasma machine

    International Nuclear Information System (INIS)

    Yasojima, Yoshiyuki; Ueda, Yoshihiro; Sasao, Hiroyuki; Ueno, Noboru; Tanaka, Toshihide

    1984-01-01

    Mitsubishi Electric has constructed a reversed-field theta-pinch machine at its Central Research Laboratory and initiated a series of plasma diagnostics and control studies for development of nuclear-fusion technology. Although the device has a linear configuration, a stable high-temperature, high-density toroidal plasma can be generated. The article describes the overall structure, vacuum system, power-supply system, and diagnostics and control system of the plasma machine. (author)

  19. Preliminary study of Rayleigh-Taylor instability in wire-array Z-pinch

    International Nuclear Information System (INIS)

    He Kaihui; Feng Kaiming; Li Qiang; Gao Chunming

    2000-01-01

    It is important to research into the MHD Rayleigh-Taylor instability developed in Z-pinch implosion. A snowplough model of the single wire Z-pinch is presented. The perturbation amplitude of Rayleigh-Taylor instability in the wire-array Z-pinch is analyzed quantitatively. Sheared axial flow is put forward to mitigate and reduce the Rayleigh-Taylor instability. And other approaches used to mitigate MHD instability in such a super-fast process are explored

  20. Effects of boundary conditions on temperature and density in an EXTRAP Z-pinch

    International Nuclear Information System (INIS)

    Drake, J.R.; Karlsson, P.

    1985-08-01

    Using the fluid equations, we examine transport in an Extrap configuration by carrying out calculations incorporating model profiles for the density and temperature. The goal of this analysis is to examine the scaling of the pinch equilibrium plasma density, temperature and radius with parameters that are characteristic for Extrap Z-pinches. These parameters include the discharge current, the neutral hydrogen filling density, an oxygen impurity fractional concentration and the condition at the pinch boundary. An Extrap Z-pinch is a pinch discharge where the current channel has a characteristic non-circular cross-section achieved by bounding the discharge by a magnetic separatrix produced when a vacuum octupole magnetic field, generated by currents in external conductors, combines with the self-magnetic field produced by the discharge current. The pinch boundary is changed from a plasma-vacuum boundary to an interface between a high-beta pinch plasma and a low-beta plasma contained in the vacuum magnetic field. The energy that is lost from the pinch region sustains this boundary layer. The introduction of a separatrix boundary around the pinch with four X-point nulls deteriorates the containment of the pinch somewhat. However the presence of the warm, low-beta plasma scrape-off layer, which provides a boundary condition on the pinch, tends to counteract the negative effects of the poorer confinement. Thus the equilibrium parameters that characterize the pinch may not be severely deteriorated by the introduction of the separatrix when the entire configuration, including the scrape-off layer, is considered. (author)

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

    International Nuclear Information System (INIS)

    Akiyama, Hidenori; Katsuki, Sunao; Lisitsyn, Igor

    1999-01-01

    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)

  2. Determination of plasma Z-pinch effect by intrinsic stimulated emission

    International Nuclear Information System (INIS)

    Lue, J.T.; Liang, J.M.

    1977-01-01

    The plasma Z-pinch behavior has been observed in a relatively small-bore diameter tube and low bank voltage discharge system. The instant of the occurrence of the laser line at 4880 A coincides with the plasma pinch time calculated by using a one-fluid snow-plow model. A determination of plasma pinch parameters by measuring the intrinsic stimulated emission of the ions is described

  3. The ZaP Flow Z-Pinch Project - Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Shumlak, Uri [Univ. of Washington, Seattle, WA (United States); Nelson, Brian A. [Univ. of Washington, Seattle, WA (United States)

    2013-12-31

    The ZaP Flow Z-Pinch Project is a project to extend the performance of the flow Z-pinch experiment at the University of Washington to investigate and isolate the relevant physics of the stabilizing effect of plasma flow. Experimental plasmas have exhibited an enhanced stability under certain operating parameters which generate a flow state (axial flows in Z-pinches and VH mode in tokamaks). Flow has also been suggested as the stabilizing mechanism in astrophysical jets.

  4. Reconsideration of the m=0 Z-pinch stability

    International Nuclear Information System (INIS)

    Scheffel, J.; Coppins, M.

    1993-01-01

    Possible paths for obtaining linear stability against the m=0 mode in the Z-pinch are studied. Using a generalized energy principle, the necessary and sufficient Chew-Goldberger-Low (CGL) m=0 stability criterion is derived. This criterion is less restrictive than that of ideal MHD, although it also requires the boundary plasma pressure to be finite. It is shown that the edge pressure cannot be stably upheld by a surface current. By instead assuming a finite pressure external gas, it is found that an edge pressure to on-axis pressure ratio of 0.5 is required for stability of a constant current density profile. A parabolic current density profile lowers the limit to the value 0.17. The growth rates are shown to be monotonically decreasing as a function of the external gas pressure. Detailed derivations of the boundary conditions are also given. The results aid in clarifying the experimental stability of four major Z-pinch experiments. Finite Larmor radius stabilization is hence required to maintain stability in future fibre pinch experiments in vacuum, implying line densities less than 10 19 m -1 . (author). 28 refs, 10 figs

  5. Nonlinear tearing modes in the reversed field pinch

    International Nuclear Information System (INIS)

    Miller, G.

    1989-01-01

    Finite-amplitude islands, which are the saturated states of tearing modes in the reversed field pinch, are calculated. These states are bifurcated noncylindrical equilibrium states. With σ(r) (σequivalentj x B/B 2 ) nonuniform across the plasma, as is consistent with experiment, a variety of m = 1 and m = 0 bifurcated equilibria are possible, instead of just the m = 1 helix calculated for uniform σ(r) by Taylor [in Pulsed High Beta Plasmas, edited by D. Evans (Pergamon, Oxford, 1976), p. 59]. Assuming the magnetic field lines in the reversed field pinch are weakly stochastic, the growth time of an unstable tearing mode is on the inertial time scale, as in the Taylor model, in constrast to growth on the resistive time scale predicted from nonlinear tearing mode theory when magnetic surfaces exist. The dependence of the saturated island width on radius of a conducting shell is investigated. Islands in the reversed field pinch often have magnetic wells in the island interior, which may result in improved confinement in the island regions

  6. X-Pinch soft x-ray source for microlithography

    International Nuclear Information System (INIS)

    Glidden, S.C.; Hammer, D.A.; Kalantar, D.H.; Qi, N.

    1993-01-01

    The x-pinch soft x-ray source is described for application in submicron resolution lithography. Experiments have been performed to characterize the radiation emitted from magnesium wire x-pinch plasmas using an 80 ns, ≤500 kA pulse. Yields of 14.2 J averaged over three independent calibrated diagnostics at 445 kA have been measured in magnesium K-shell radiation (predominantly 8.4 angstrom to 9.4 angstrom or 1.5 keV to 1.3 keV) from a submillimeter source, with as little as 5-10% of the yield below the 6.74 angstrom silicon absorption edge. A new ≤700 kA, 100 ns pulser being used for x-pinch physics experiments is described. The design of a 40 pulse per second pulsed power system and wire loading mechanism for exposing a resist in 1 second at a distance 40 cm is presented

  7. 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.

  8. Two-dimensional integrated Z-pinch ICF design simulations

    Energy Technology Data Exchange (ETDEWEB)

    Lash, J.S.

    1999-07-01

    The dynamic hohlraum ICF concept for a Z-pinch driver utilizes the imploding wire array collision with a target to produce a radiation history suitable for driving an embedded inertial confinement fusion (ICF) capsule. This target may consist of various shaped layers of low-density foams or solid-density materials. The use of detailed radiation magneto-hydrodynamic (RMHD) modeling is required for understanding and designing these complex systems. Critical to producing credible simulations and designs is inclusion of the Rayleigh-Taylor unstable wire-array dynamics; the bubble and spike structure of the collapsing sheath may yield regions of low-opacity enhancing radiation loss as well as introduce non-uniformities in the capsule's radiation drive. Recent improvements in LASNEX have allowed significant progress to be made in the modeling of unstable z-pinch implosions. Combining this with the proven ICF capsule design capabilities of LASNEX, the authors now have the modeling tools to produce credible, fully-integrated ICF dynamic hohlraum simulations. They present detailed two-dimensional RMHD simulations of recent ICF dynamic hohlraum experiments on the Sandia Z-machine as well as design simulations for the next-generation Z-pinch facility and future high-yield facility.

  9. Two-dimensional integrated Z-pinch ICF design simulations

    International Nuclear Information System (INIS)

    Lash, J.S.

    1999-01-01

    The dynamic hohlraum ICF concept for a Z-pinch driver utilizes the imploding wire array collision with a target to produce a radiation history suitable for driving an embedded inertial confinement fusion (ICF) capsule. This target may consist of various shaped layers of low-density foams or solid-density materials. The use of detailed radiation magneto-hydrodynamic (RMHD) modeling is required for understanding and designing these complex systems. Critical to producing credible simulations and designs is inclusion of the Rayleigh-Taylor unstable wire-array dynamics; the bubble and spike structure of the collapsing sheath may yield regions of low-opacity enhancing radiation loss as well as introduce non-uniformities in the capsule's radiation drive. Recent improvements in LASNEX have allowed significant progress to be made in the modeling of unstable z-pinch implosions. Combining this with the proven ICF capsule design capabilities of LASNEX, the authors now have the modeling tools to produce credible, fully-integrated ICF dynamic hohlraum simulations. They present detailed two-dimensional RMHD simulations of recent ICF dynamic hohlraum experiments on the Sandia Z-machine as well as design simulations for the next-generation Z-pinch facility and future high-yield facility

  10. 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.

  11. Pinch Related Research At Institute For Plasma Research, India

    International Nuclear Information System (INIS)

    Shyam, Anurag

    2006-01-01

    Several pinch related experiment, their drivers and related diagnostics are being developed in our laboratory. The first set of experiments is to investigate various aspects of magnetized target fusion (MTF/MAGO). To drive the liner, in Z or theta pinch configuration, a 1.2 MJ, 3.6 MA capacitor bank is developed. For liner diagnostics flash radiography, VISAR and pyrometery are being developed. To produce magnetized (target) plasma a 120 kJ, 3 MA and several other banks are developed. Hot magnetized Plasma will be diagnosed by optical schlieren, interferometery and X-Ray spectrometry. A terra-watt system consisting of a Marx bank and water line delivering 800 kA at 1.6 MV will be commissioned, soon. The device will be used to study different pinch (wire array) configurations for production of electro-magnetic radiations. Smaller pulsed power systems, consisting of 1MV/500 kV Marx bank/tesla transformer and than water or solid state (cables) pulse forming network (coax) are also being developed for capillary discharge and other experiments. Two plasma foci experiments are also being conducted. The effort is produce a repetitively operating compact plasma focus

  12. ANALISIS COMPARADO SOBRE LA RESPONSABILIDAD SOCIAL EMPRESARIAL EN AMERICA LATINA Y EL ECUADOR

    Directory of Open Access Journals (Sweden)

    Sofia Lovato

    2016-04-01

    Full Text Available El presente estudio comparado concibe una serie de reflexiones generales desde la perspectiva social, pobreza para el analisis de la Responsabilidad Social, incorpornado la relacion políticas gubernamentales o estadp y empresa, que facilite la implementacion de la resposabilidad social empresarial en América Latina y el Ecuador como respuesta a la globalizacion considerándose un desafio para la sociedad internacional, los paises de America Latina se encuentra en etapa de confusion debido a que no existe un consenso en q ue consiste la repsonsabilidad social empresarial que permita una adecuada aplicacion de la misma a nivel internacional con el propósito de contribuis al desarrollo socioeconómico de la region mejorando la calidad de v ida de la sociedad.

  13. ANALISIS METODOLÓGICO PARA LA MODELACIÓN DE LA SEGURIDAD ALIMENTARIA A NIVEL NACIONAL ANALISE METODOLÓGICO PARA A MODELAÇÃO DE A SEGURIDADE ALIMENTAR A NÍVEL NACIONAL METHODOLOGICAL ANALYSIS TO MODELING FOOD SECURITY FROM A NATIONAL PERSPECTIVE

    Directory of Open Access Journals (Sweden)

    DIANA P GIRALDO

    2010-06-01

    Full Text Available La comunidad científica y política ha incrementado el interés por entender e intervenir el problema de seguridad alimentaria, especialmente desde la crisis alimentaria en la década de los 70's. Diferentes estrategias metodológicas han sido utilizadas con el ánimo de proyectar, predecir y evaluar políticas como soporte para la toma de decisiones en el sector público. Este artículo explora un conjunto de metodologías usadas para el estudio de la seguridad alimentaria a nivel nacional, herramientas estratégicas para una apropiada formulación, evaluación y aplicación de políticas. Se discute el potencial uso de metodologías complementarias al análisis tradicional, especialmente la Dinámica de Sistemas, como una herramienta de simulación que permite el análisis de relaciones causales, el establecimiento de variables críticas y la evaluación de escenarios a favor de una efectiva toma de decisionesA comunidade científica e política hão acrescentado o interesse por entender e intervir o problema de seguridade alimentar, especialmente, desde a crise alimentar na década dos 70's. Diferentes estratégias metodológicas hão sido utilizadas com o interesse de projetar, predizer e avaliar políticas como suportes para a toma de decisões no setor público. Este artigo explora um conjunto de metodologias empregadas no estudo da seguridade alimentar a nível nacional, ferramentas estratégicas para uma apropriada formulação, avaliação e aplicação de políticas. Discutese o potencial uso de metodologias complementárias à análise tradicional, especialmente a Dinâmica de Sistemas, como ferramentas de simulação que permite a analise de relações causais, o estabelecimento de variáveis críticas e a avaliação de cenários a favor de uma toma de decisõesThe scientific and politic community has had increasing concerns for strategic understanding and intervention of the food security problem, especially since the 70's food

  14. Instrumento para classificação de pacientes: opinião de usuários e análise de indicadores de cuidado Instrumento para clasificación de pacientes: opinión de los usuarios y análisis de indicadores del cuidado Instrument for patient classification: users' opinions and analisys of healthcare indicators

    Directory of Open Access Journals (Sweden)

    Marcia Galan Perroca

    2008-12-01

    Full Text Available Esta pesquisa descritiva foi conduzida com o intuito de: 1.investigar a opinião de usuários sobre um instrumento de classificação de pacientes; e 2. analisar os indicadores de cuidados que mais contribuem para a classificação dos pacientes nas diferentes categorias de cuidados. A opinião dos 24 usuários foi obtida por meio de questionário. O instrumento de classificação foi aplicado em 796 pacientes em um hospital de ensino no interior do Estado de São Paulo, no período de setembro de 2006 a maio de 2007. Para o tratamento estatístico, utilizou-se a Análise de Componentes Principais (ACP e Análise Discriminante. Os usuários investigados mostraram-se satisfeitos com o instrumento utilizado, mas apontaram uma tendência do mesmo à subestimar a categoria de cuidados à qual o paciente pertence. Os resultados evidenciaram os indicadores Terapêutica, Cuidado Corporal, Educação à Saúde e Integridade Cutâneo-Mucosa como aqueles com maior capacidade discriminatória. A classificação correta dos pacientes variou de 89,8% (cuidados semi-intensivos a 95,6% (cuidados intensivos.Investigación descriptiva conducida con la intención de: 1.investigar la opinión de los usuarios con relación a un instrumento de clasificación de pacientes y 2. analizar los indicadores de cuidados que más contribuyeron para clasificar pacientes en sus diferentes categorías de cuidados. La opinión de los 24 usuarios fue obtenida a través de un cuestionario. El instrumento de clasificación fue aplicado en 796 pacientes de un hospital de enseñanza del interior de São Paulo, durante setiembre del 2006 a mayo del 2007. El análisis estadístico realizado por Análisis de Componentes Principales (ACP y Discriminativo. Los usuarios se mostraron satisfechos con el instrumento utilizado, sin embargo indicaron una tendencia del mismo para subestimar la categoría de cuidado al cual el paciente pertenece. Los resultados mostraron los indicadores: Terap

  15. Metal Wire-array Load for Z-pinch Used as X-ray Source

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    <正> The inertial confinement fusion (ICF) has evident minatory applications becasuse ICF ignites the fusion fuel with high energy media. As a method of ICF, Z-pinch has obtained evidently increased X-ray power PX-ray and energy EX-ray. The scientists have noticed this promising achievement. The Z-accelerator which is an operating Z-pinch device in Sandia national laboratory (SNL) in USA achieved 290 TW Px-ray in 1997 and the energy and defense departments of USA will finance SNL for a larger Z-pinch device. The early Z-pinch aimed to obtain high tempera

  16. Energy balance in a Z pinch with suppressed Rayleigh-Taylor instability

    Science.gov (United States)

    Baksht, R. B.; Oreshkin, V. I.; Rousskikh, A. G.; Zhigalin, A. S.

    2018-03-01

    At present Z-pinch has evolved into a powerful plasma source of soft x-ray. This paper considers the energy balance in a radiating metallic gas-puff Z pinch. In this type of Z pinch, a power-law density distribution is realized, promoting suppression of Rayleigh-Taylor (RT) instabilities that occur in the pinch plasma during compression. The energy coupled into the pinch plasma, is determined as the difference between the total energy delivered to the load from the generator and the magnetic energy of the load inductance. A calibrated voltage divider and a Rogowski coil were used to determine the coupled energy and the load inductance. Time-gated optical imaging of the pinch plasma showed its stable compression up to the stagnation phase. The pinch implosion was simulated using a 1D two-temperature radiative magnetohydrodynamic code. Comparison of the experimental and simulation results has shown that the simulation adequately describes the pinch dynamics for conditions in which RT instability is suppressed. It has been found that the proportion of the Ohmic heating in the energy balance of a Z pinch with suppressed RT instability is determined by Spitzer resistance and makes no more than ten percent.

  17. A Reactor Development Scenario for the FuZE Sheared-Flow Stabilized Z-pinch

    Science.gov (United States)

    McLean, Harry S.; Higginson, D. P.; Schmidt, A.; Tummel, K. K.; Shumlak, U.; Nelson, B. A.; Claveau, E. L.; Forbes, E. G.; Golingo, R. P.; Stepanov, A. D.; Weber, T. R.; Zhang, Y.

    2017-10-01

    We present a conceptual design, scaling calculations, and development path for a pulsed fusion reactor based on a flow-stabilized Z-pinch. Experiments performed on the ZaP and ZaP-HD devices have largely demonstrated the basic physics of sheared-flow stabilization at pinch currents up to 100 kA. Initial experiments on the FuZE device, a high-power upgrade of ZaP, have achieved 20 usec of stability at pinch current 100-200 kA and pinch diameter few mm for a pinch length of 50 cm. Scaling calculations based on a quasi-steady-state power balance show that extending stable duration to 100 usec at a pinch current of 1.5 MA and pinch length of 50 cm, results in a reactor plant Q 5. Future performance milestones are proposed for pinch currents of: 300 kA, where Te and Ti are calculated to exceed 1-2 keV; 700 kA, where DT fusion power would be expected to exceed pinch input power; and 1 MA, where fusion energy per pulse exceeds input energy per pulse. This work funded by USDOE ARPA-E and performed under the auspices of Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-734770.

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

    International Nuclear Information System (INIS)

    Boyd, J.K.; Mark, J.W.K.; Sharp, W.M.; Yu, S.S.

    1984-01-01

    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

  19. Numerical simulation on the screw pinch by 2-D MHD pinch code 'topics' including impurities and neutrals effects

    International Nuclear Information System (INIS)

    Nagata, A.; Ashida, H.; Okamoto, M.; Hirano, K.

    1981-03-01

    Two dimentional fluid simulation code ''TOPICS'' is developed for the STP-2, the shock heated screw pinch at Nagoya. It involves the effects of impurity ions and neutral atoms. In order to estimate the radiation losses, the impurity continuity equations with ionizations and recombinations are solved simultaneously with the plasma fluid equations. The results are compared with the coronal equilibrium model. It is found that the coronal equilibrium model underestimates the radiation losses from shock heated pinch plasmas in its initial dynamic phase. The present calculations including impurities and neutrals show the importance of the radiation losses from the plasma of the STP-2. Introducing the anomalous resistivity caused by the ion acoustic instability, the observed magnetic field penetration is explained fairly well. (author)

  20. Self-pinched transport of intense ion beams

    International Nuclear Information System (INIS)

    Ottinger, P.F.; Neri, J.M.; Stephanakis, S.J.

    1999-01-01

    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

  1. 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

  2. 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.

  3. Uncertainty and sensitivity analysis methodology in a level-I PSA (Probabilistic Safety Assessment); Analisis de incertidumbres y sensibilidad aen un APS (Analisis Probabilistico de Seguridad) nivel-I

    Energy Technology Data Exchange (ETDEWEB)

    Nunez McLeod, J E; Rivera, S S [Universidad Nacional de Cuyo, Mendoza (Argentina). Instituto de Capacitacion Especial y Desarrollo de Ingenieria Asistida por Computadora (CEDIAC)

    1997-07-01

    This work presents a methodology for sensitivity and uncertainty analysis, applicable to a probabilistic safety assessment level I. The work contents are: correct association of distributions to parameters, importance and qualification of expert opinions, generations of samples according to sample sizes, and study of the relationships among system variables and system response. A series of statistical-mathematical techniques are recommended along the development of the analysis methodology, as well different graphical visualization for the control of the study. (author) [Spanish] En este trabajo se presenta una metodologia de analisis de sensibilidad e incertidumbres, aplicable a un analisis probabilistico de seguridad (APS) de nivel I. En el cual se plantea: la adecuada asociacion de distribuciones a variables, la importancia y penalizacion de la opinion de expertos, la generacion de muestras y su tamano, y el estudio de las relaciones entre las variables del sistema y la respuesta de este. Ademas durante el desarrollo de la metodologia de analisis se recomiendan una serie de tecnicas estadistico-matematicas y tipos de visualizacion grafica para el control del estudio. (autor)

  4. ANALISIS PERIKANAN HUHATE DI PERAIRAN LARANTUKA, FLORES

    Directory of Open Access Journals (Sweden)

    Mohamad Adha Akbar

    2016-11-01

    Full Text Available Informasi mengenai beberapa aspek perikanan huhate sangat diperlukan sebagai bahan untuk perencanaan pengelolaan perikanan yang berkelanjutan. Penelitian ini dilakukan di Larantuka, Flores Timur pada tahun 2014 dengan tujuan untuk menganalisis perikanan huhate sebagai salah satu tulang punggung perikanan TCT. Kegiatan penelitian diprioritaskan pada analisis unit alat tangkap, daerah penangkapan, komposisi hasil tangkapan dan estimasi Total Faktor Produktivitas (TFP perikanan huhate. Basis data pengukuran adalah himpunan  data pendaratan dan observasi lapang. Hasil penelitian menunjukan bahwa karakteristik armada terdiri dari kapal yang terbuat dari fibreglass dengan kisaran bobot kapal 6 - 30 GT. Daerah penangkapan di sekitar perairan Laut Sawu dan Laut Flores. Hasil tangkapan utama didominansi oleh cakalang (Katsuwonus pelamis sebanyak 82%, juwana tuna (Thunnus spp. 17% dan tongkol (Auxis spp. 1% serta hasil tangkapan ikutan lemadang (Coryphaena hippurus dan marlin (Makaira spp. < 1%. Hasil analisis tangkapan per unit upaya (CPUE memberikan nilai rata-rata sebesar 1,1 ton/trip (0,4-1,7 ton/trip dengan nilai tertinggi terjadi pada Februari, sedangkan terendah terjadi pada Januari. Hasil penelitian menunjukkan terdapat hubungan yang signifikan antara tren bulanan CPUE dan nilai TFP.

  5. ANALISIS PENGELOLAAN LINGKUNGAN PERMUKIMAN DI KABUPATEN SOPPENG

    Directory of Open Access Journals (Sweden)

    Bakhrani Rauf

    2016-08-01

    Full Text Available Penelitian ini  bertujuan untuk mendeskripsikan pengelolaan lingkungan permukiman di Kabupaten Soppeng pada aspek: (1 penyediaan dan penanganan lahan terbuka hijau (open space; (2 penyediaan dan penanganan drainase; (3  penanganan sampah; (4 penyediaan dan penanganan pembuangan veses (septic tank. Jenis penelitian ini adalah penelitian kuantitatif dengan pendekatan survei.  Sampel wailayah penelitian ini adalah satu RW di ibu kota kabupaten dan satu RW di desa yang dipilih dengan metode purpossive sampling,  yaitu RW yang sudah maju di ibu kota kabupaten dan RW yang tertinggal di desa. Responden sebanyak 50 kepala keluarga yakni masing-masing 25 kepala keuarga di setiap RW, dipilih dengan  systematic random sampling.  Teknik pengumpulan data yang dilakukan adalah melakukan observasi langsung dan dilengkapi dengan wawancara terhadap responden. Analisis yang digunakan adalah analisis deskriptif. Hasil penelitian menunjukkan bahwa pengelolaan lingkungan permukiman di Kabupaten Soppeng pada aspek: (1 ketersediaan dan penanganan lahan terbuka hijau (open space ditemukan belum memadai; (2 ketersediaan drainase (air kotor dan air hujan ditemukan belum memadai; (3 Penanganan sampahbelum memadai; dan (4 penanganan veses dan penyediaan septic tankbelum memadai.

  6. IDENTIFIKASI MISKONSEPSI SISWA SMP PADA KONSEP FOTOSINTESIS MELALUI ANALISIS GAMBAR

    Directory of Open Access Journals (Sweden)

    Devi Ariandini

    2014-01-01

    Full Text Available Tujuan dari penelitian ini adalah untuk mengidentifikasi miskonsepsi siswa dengan analisis menggambar. Tiga puluh empat siswa di kelas 8 di sekolah menengah pertama digunakan sebagai subyek dalam penelitian ini. Teknik sampel menggunakan teknik purposive sampling. Data yang diperlukan untuk penelitian ini dikumpulkan melalui kuesioner, menggambar analisis rubrik, dan wawancara. Identifikasi Kesalahpahaman ditentukan dengan menggambar siswa berdasarkan menggambar kriteria klasifikasi oleh Kose (2008. Siswa diperintahkan untuk menarik tentang konsep fotosintesis setelah proses pembelajaran. Gambar siswa dianalisis dengan rubrik dan setelah itu mereka diwawancarai. Hasil penelitian menunjukkan tidak semua tingkat kriteria menggambar dari tingkat 1 sampai 5 diidentifikasi. Dari hasil analisa, gambar paling banyak ditemukan adalah pada tingkat 4. Gambar pada tingkat 4 dikategorikan sebagai gambar lengkap konsep fotosintesis dan tidak ada kesalahpahaman ditemukan. Berdasarkan gambar mereka, ada siswa 2,9% diidentifikasi yang diselenggarakan kesalahpahaman. Ada perbedaan jumlah siswa yang diadakan kesalahpahaman antara gambar hasil analisis dan hasil wawancara. Dari hasil wawancara, ada siswa 35,2% dimiliki kesalahpahaman, lebih dari menggambar hasil analisis. Ini berarti bahwa identifikasi kesalahpahaman melalui analisis gambar tidak efektif. Kesalahpahaman siswa yang paling sering terjadi pada konsep fotosintesis adalah tempat berlangsungnya fotosintesis. Faktor yang membuat kesalahpahaman siswa yaitu karena siswa itu sendiri dan lingkungannya. Kata Kunci: fotosintesis, kesalahpahaman, konsep, menggambar analisis

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

    International Nuclear Information System (INIS)

    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

  8. Torus C-I field reversed theta-pinch at UNICAMP

    International Nuclear Information System (INIS)

    Machida, M.; Collares, M.P.; Honda, R.Y.; Sakanaka, P.H.; Scheid, V.H.B.

    1984-01-01

    The influence of multipole fields (octopole and quadrupole) on supressing the n=2 rotational instability, field reconnection, particle loss effects is studied, and the viability of transforming the theta-pinch from Campinas, Brazil (100Kv, 55Kj) to the field reversed theta-pinch with plasma translation program is analyzed. (E.G.) [pt

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

    International Nuclear Information System (INIS)

    Colombant, D.; Mosher, D.

    1989-01-01

    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

  10. Experiments on the ZT-S reversed-field pinch, August--December 1978

    International Nuclear Information System (INIS)

    Jacobson, A.R.

    1979-06-01

    During the latter half of 1978 the ZT-S reversed-field pinch was used to explore the utility of pitch-programming techniques in setting up stable diffuse pinch profiles. Several experimental observations relating to this goal are presented

  11. High-energy electron acceleration in the gas-puff Z-pinch plasma

    Energy Technology Data Exchange (ETDEWEB)

    Takasugi, Keiichi, E-mail: takasugi@phys.cst.nihon-u.ac.jp [Institute of Quantum Science, Nihon University, 1-8 Kanda-Surugadai, Chiyoda, Tokyo 101-8308 (Japan); Miyazaki, Takanori [Institute of Quantum Science, Nihon University, 1-8 Kanda-Surugadai, Chiyoda, Tokyo 101-8308, Japan and Dept. Innovation Systems Eng., Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi 321-8585 (Japan); Nishio, Mineyuki [Anan National College of Technology, 265 Aoki, Minobayashi, Anan, Tokushima 774-0017 (Japan)

    2014-12-15

    The characteristics of hard x-ray generation were examined in the gas-puff z-pinch experiment. The experiment on reversing the voltage was conducted. In both of the positive and negative discharges, the x-ray was generated only from the anode surface, so it was considered that the electrons were accelerated by the induced electromagnetic force at the pinch time.

  12. ANALISIS POSISI BERSAING UNTUK MENENTUKAN STRATEGI PEMASARAN INDUSTRI KRIPIK TEMPE DI KOTA MALANG

    Directory of Open Access Journals (Sweden)

    Rusno Rusno

    2014-11-01

    Full Text Available Industri kripik tempe di desa Sanan Malang merupakan bagian dari UMKM mengalami perkembang-an yang cukup baik. Hingga akhir tahun 2013 kemarin berjumlah kurang lebih 65 pengrajin, bahkan saat ini Sanan sudah menjadi sentra industri kecil penghasil kripik tempe dan menjadi salah satu pro-duk unggulan kota Malang. Namun dalam perjalanannya industri ini banyak mengalami masalah diantaranya banyak pesaing yang terus masuk dalam bisnis ini. Hal ini mengakibatkan persaingan yang semakin ketat sehingga para pelaku harus dapat menentukan strategi untuk dapat memenangkan persaingan, maka Tujuan dalam penelitian ini adalah untuk mengetahui bagaimana posisi bersaing dan penetapan strategi pemasaran produsen kripik tempe di kota Malang. Jenis penelitian ini adalah confirmatory research. Sebagai populasinya adalah pengusaha kripik tempe yang berlokasi di kecamatan Blimbing kota Malang yang berjumlah 65 pemilik home industri. Sampel dilakukan dengan teknik Simple random sampling berjumlah 33 pengusaha industri kripik tempe. Pengambilan data dilakukan dengan kuesioner, dan teknik analisis data dengan teknik deskriptif dan tabulasi silang. Berdasarkan analisis data didapatkan hasil penelitian bahwa posisi bersaing industri kripik tempe di Sanan terdapat 4 cluster yang terbagi dalam : Cluster 1 (pemimpin pasar/market leader beranggota-kan 1 perusahaan. Cluster 2(penceruk pasar/market nicher beranggotakan 13 perusahaan, Cluster 3 (penantang pasar/market challenger beranggotakan 8 perusahaan dan cluster 4 (pengikut pasar /market follower beranggotakan 11 perusahaan. 

  13. TUGAS DAN WEWENANG PUSAT PELAPORAN DAN ANALISIS TRANSAKSI KEUANGAN (PPATK DALAM PEMBERANTASAN TINDAK PIDANA PENCUCIAN UANG

    Directory of Open Access Journals (Sweden)

    Johari Johari

    2014-03-01

    Full Text Available Tugas dan wewenang Pusat Pelaporan dan Analisis Transaksi Keuangan (PPATK terdapat di dalam Pasal 26 dan Pasal 27 Undang-Undang No. 25 Tahun 2003 tentang Tindak Pencucian Uang. Berdasarkan ketentuan tersebut, tugas dan wewenang PPATK tersebut bertujuan untuk mendeteksi terjadinya tindak pidana pencucian uang, dan membantu penegakan hukum yang berkaitan dengan pencucian uang, termasuk tindak pidana asal yang melahirkannya (predicate offences. Namun, Peranan PPATK akan berjalan secara efektif apabila aparat penegak hukum seperti Kepolisian, Kejaksaan, Pengadilan, Bea dan Cukai, para regulator seperti Bank Indonesia, Departemen Keuangan, Badan Pengawas Pasar Modal serta Penyedia Jasa Keuangan, industri perbankan, asuransi, perusahaan pembiayaan, dana pensiun, perusahaan efek, pengelola reksadana, media massa, masyarakat bekerjasama secara terorganisir dan terpadu dalam pemberantasan tindak pencucian uang di Indonesia. Dengan kewenangan yang dimilikinya, PPATK dapat mengejar hasil dari kejahatan, apabila hasil kejahatan tersebut dapat dikejar dan disita maka negara dengan sendirinya akan mengurangi tindak kejahatan itu sendiri. Kata kunci : Pencucian uang, tindak pidana pencucian uang (money laundering, kejahatan terorganisir, dan Pusat Pelaporan dan Analisis Transaksi Keuangan (PPATK.

  14. ANALISIS BEBAN KERJA DENGAN MENGGUNAKAN METODE CVL DAN NASATLX DI PT. ABC

    Directory of Open Access Journals (Sweden)

    Renty Anugerah Mahaji Puteri

    2017-10-01

    Full Text Available PT. ABC merupakan perusahaan Jepang yang bergerak di bidang usaha jasa konstruksi mekanikal, elektrikal, dan system komunikasi. Sebagai perusahaan jasa konstruksi, PT. ABC dituntut untuk mencapai tujuan / target perusahaan tiap tahunnya yaitu mendapatkan tender proyek, maka tak jarang karyawannya dituntut untuk lembur. Seringnya karyawan lembur, maka menimbulkan masalah kelelahan terhadap para karyawannya sehingga target tidak tercapai. Penelitian ini bertujuan untuk mengevaluasi beban kerja yang dialami oleh engineer leader pada Departemen DesaindanOperasional di PT. ABC. Beban kerja yang diukur adalah beban kerja fisik dan mental. Beban kerja fisik diukur berdasarkan cardiovascular load (CVL. Beban kerja mental diukur dengan menggunakan metode NASA-Task Load Index (NASA-TLX. Berdasarkan hasil analisis CVL, beban kerja fisik yang diterima engineer proyek memiliki presentase CVL sebesar 31,16%, denganhasilperbaikanmenjadi 23,38%. Sedangkan dari hasil analisis NASA-TLX, beban kerja mental yang diterima engineer proyek yaitu dengan skor NASA-TLX 74,2% denganhasilperbaikanmenjadi 51,6%, sedangkan skor NASA-TLX engineer head office 61,5% denganhasilperbaikanmenjadi 47,66%.

  15. Analisis Daya Saing untuk Meningkatkan Kualitas Layanan terhadap Pelanggan dengan Pendekatan CRM di CV. BLITZSPOT

    Directory of Open Access Journals (Sweden)

    Suryadi Muhammad

    2017-04-01

    Full Text Available CV. Blitzspot adalah perusahaan yang bergerak di bidang jasa penyediaan layanan internet (internet service provider, yang berkantor pusat di Komplek Padasuka Indah Ruko Blok A-1, Cimahi, Jawa Barat. Berdasarkan hasil wawancara dan hasil observasi pada data transaksi CV. Blitzspot, konsumen CV. Blitzspot yang melakukan transaksi tiap tahunnya selalu berkurang, hal ini dikarenakan konsumen sering membandingkan layanan-layanan yang ditawarkan oleh para pesaing CV. Blitzspot. Bila permasalahan tersebut belum teratasi, konsumen CV. Blitzspot akan menurun tiap tahunnya dan akan selalu berpindah ke pesaing CV. Blitzspot. Direktur Utama CV. Blitzspot ingin menganalisis daya saing untuk menentukan layanan-layanan yang akan diberikan kepada pelanggan CV. Blitzspot dan penentuan strategi untuk mempertahankan konsumen CV. Blitzspot.  Metode Analisis daya saing yang digunakan adalah Model Analisis Berlian Porter dan Metode Pengelompokkan Pelanggan yang digunakan adalah Metode LRFM. Berdasarkan hasil pengujian dan pembahasan yang telah dibuat, maka dapat ditarik kesimpulan bahwa Direktur Utama dapat menganalisis daya saing CV. Blitzspot dengan menggunakan Berlian Porter untuk meningkatkan kualitas layanan terhadap pelanggan CV. Blitzspot.

  16. Modelling high density phenomena in hydrogen fibre Z-pinches

    International Nuclear Information System (INIS)

    Chittenden, J.P.

    1990-09-01

    The application of hydrogen fibre Z-pinches to the study of the radiative collapse phenomenon is studied computationally. Two areas of difficulty, the formation of a fully ionized pinch from a cryogenic fibre and the processes leading to collapse termination, are addressed in detail. A zero-D model based on the energy equation highlights the importance of particle end losses and changes in the Coulomb logarithm upon collapse initiation and termination. A 1-D Lagrangian resistive MHD code shows the importance of the changing radial profile shapes, particularly in delaying collapse termination. A 1-D, three fluid MHD code is developed to model the ionization of the fibre by thermal conduction from a high temperature surface corona to the cold core. Rate equations for collisional ionization, 3-body recombination and equilibration are solved in tandem with fluid equations for the electrons, ions and neutrals. Continuum lowering is found to assist ionization at the corona-core interface. The high density plasma phenomena responsible for radiative collapse termination are identified as the self-trapping of radiation and free electron degeneracy. A radiation transport model and computational analogues for the effects of degeneracy upon the equation of state, transport coefficients and opacity are implemented in the 1-D, single fluid model. As opacity increases the emergent spectrum is observed to become increasingly Planckian and a fall off in radiative cooling at small radii and low frequencies occurs giving rise to collapse termination. Electron degeneracy terminates radiative collapse by supplementing the radial pressure gradient until the electromagnetic pinch force is balanced. Collapse termination is found to be a hybrid process of opacity and degeneracy effects across a wide range of line densities with opacity dominant at large line densities but with electron degeneracy becoming increasingly important at lower line densities. (author)

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

    International Nuclear Information System (INIS)

    Hamann, F.

    2003-12-01

    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)

  18. Overview of the Fusion Z-Pinch Experiment FuZE

    Science.gov (United States)

    Weber, T. R.; Shumlak, U.; Nelson, B. A.; Golingo, R. P.; Claveau, E. L.; McLean, H. S.; Tummel, K. K.; Higginson, D. P.; Schmidt, A. E.; UW/LLNL Team

    2016-10-01

    Previously, the ZaP device, at the University of Washington, demonstrated sheared flow stabilized (SFS) Z-pinch plasmas. Instabilities that have historically plagued Z-pinch plasma confinement were mitigated using sheared flows generated from a coaxial plasma gun of the Marshall type. Based on these results, a new SFS Z-pinch experiment, the Fusion Z-pinch Experiment (FuZE), has been constructed. FuZE is designed to investigate the scaling of SFS Z-pinch plasmas towards fusion conditions. The experiment will be supported by high fidelity physics modeling using kinetic and fluid simulations. Initial plans are in place for a pulsed fusion reactor following the results of FuZE. Notably, the design relies on proven commercial technologies, including a modest discharge current (1.5 MA) and voltage (40 kV), and liquid metal electrodes. Supported by DoE FES, NNSA, and ARPA-E ALPHA.

  19. Experimental study of the 'NOVA' Z-pinch equipment working as vacuum-gap

    International Nuclear Information System (INIS)

    Acuna, H.; Bernal, L.; Cortazar, D.; Iglesias, G.; Pouzo, J.

    1990-01-01

    The Z-pinch device 'NOVA' (2 kjoule, 10 kV, 250 kA) is operated as a vacuum gap. The plasma is generated in high vacuum (10 -5 mb) by the material let loose from the copper electrodes. Many strong compressions (micro pinches) are produced in the pinch column over the first quarter of the current period. This is detected by the observable pulses in the dI/dt signal. Hard X-rays generated in coincidence with the micro pinches are detected using a scintillator-photomultiplier system. This work studies the plasma evolution, by taking pictures of the pinch with obturation times of about 15 ns, temporally correlated with the dI/dt signal. Instabilities of types m=0 and m=1 are observed. (Author). 3 refs., 6 figs

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

    International Nuclear Information System (INIS)

    Vikhrev, V.V.; Ivanov, V.V.; Rozanova, G.A.

    1993-01-01

    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

  1. High current density toroidal pinch discharges with weak toroidal fields

    International Nuclear Information System (INIS)

    Brunsell, P.; Brzozowski, J.; Drake, J.R.; Hellblom, G.; Kaellne, E.; Mazur, S.; Nordlund, P.

    1990-01-01

    Toroidal discharges in the ultralow q regime (ULQ) have been studied in the rebuilt Extrap TI device. ULQ discharges are sustained for pulse lengths exceeding 1 ms, which corresponds to more than 10 resistiv shell times. Values for the safety factor at the vacuum vessel wall are between rational values: 1/(n+1) -2 . The magnetic fluctuation level increases during the transition between rational values of q(a). For very low values of q(a), the loop voltage increases and the toroidal field development in the discharge exhibits the characteristic behaviour of the setting-up phase of a field reversed pinch. (author) 1 ref., 2 figs., 1 tab

  2. 3-dimensional simulation of dynamo effect of reversed field pinch

    International Nuclear Information System (INIS)

    Koide, Shinji.

    1990-09-01

    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 10 3 5 , while Nebel, Caramana and Schnack obtained the fluctuation level is independent of S for a pressureless RFP plasma. (author)

  3. Electron temperature diagnostics in the RFX reversed field pinch experiment

    International Nuclear Information System (INIS)

    Bartiromo, R.; Carraro, L.; Marrelli, L.; Murari, A.; Pasqualotto, R.; Puiatti, M.E.; Scarin, P.; Valisa, M.; Franz, P.; Martin, P.; Zabeo, L.

    2000-01-01

    The paper presents an integrated approach to the problem of electron temperature diagnostics of the plasma in a reversed field pinch. Three different methods, sampling different portions of the electron distribution function, are adopted, namely Thomson scattering, soft X-ray spectroscopy by pulse-height analysis and filtered soft X-ray intensity ratio. A careful analysis of the different sources of systematic errors is performed and a novel statistical approach is adopted to mutually validate the three independent measurements. A satisfactory agreement is obtained over a large range of experimental conditions, indicating that in the plasma core the energy distribution function is well represented by a maxwellian. (author)

  4. Optimization of gas target production for Z-pinch implosions

    International Nuclear Information System (INIS)

    Semushin, S.; Etlicher, B.; Rouille, C.

    1996-01-01

    Optimization of shell parameters for further imploding in a Z-pinch has been done. The nozzle shape was selected with the help of two-dimensional gas dynamics computer simulation. The influence of the electrode configuration was taken into account during the optimization. Two types of nozzle are presented. The advanced design with three gaseous shells may use different gases. The other design is based on aluminium vapor jet. The designs were tested by interferometry. The resulting mass distributions are analyzed by a real experiment and by means of 2D MHD computer simulations. The new nozzles provide smaller zippering, higher radiation power and better reproducible results. (author). 4 figs., 4 refs

  5. Conical pinched electron beam diode for intense ion beam source

    International Nuclear Information System (INIS)

    Matsukawa, Yoshinobu; Nakagawa, Yoshiro

    1982-01-01

    For the purpose of improvement of the pinched electron beam diode, the production of an ion beam by a diode with electrodes in a conical shape was studied at low voltage operation (--200 kV). The ion beam is emitted from a small region of the diode apex. The mean ion beam current density near the axis at 12 cm from the diode apex is two or three times that from an usual flat parallel diode with the same dimension and impedance. The brightness and the power brightness at the otigin are 450 MA/cm 2 sr and 0.12 TW/cm 2 sr respectively. (author)

  6. Ion current reduction in pinched electron beam diodes

    International Nuclear Information System (INIS)

    Quintenz, J.P.; Poukey, J.W.

    1977-01-01

    A new version of a particle-in-cell diode code has been written which permits the accurate treatment of higher-current diodes with greater physical dimensions. Using this code, we have studied ways to reduce the ion current in large-aspect-ratio pinched electron beam diodes. In particular, we find that allowing the ions to reflex in such diodes lowers the ion to electron current ratio considerably. In a 3-MV R/d=24 case this ratio was lowered by a factor of 6--8 compared with the corresponding nonreflexing-ion diode, while still producing a superpinched electron beam

  7. Spectroscopical studies of impurities in the belt pinch HECTOR

    International Nuclear Information System (INIS)

    Singethan, J.

    1981-04-01

    In this paper UV-line-intensity measurements of impurities are presented, which have been performed in the belt-pinch HECTOR. From the line-intensities impurity concentrations and information on the radiation losses is be obtained. At temperatures below 100 eV, the energy loss due to line emission of oxygen and carbon impurities is one of the most important electron energy loss mechanisms. Thus the measurement and calculation of the radiation losses is of particular relevance. Furthermore the electron temperature time dependence can be obtained by comparing the line intensity time dependence with the solution of the respective rate equations. (orig./HT) [de

  8. Energy Conversion in Imploding Z-Pinch Plasma

    International Nuclear Information System (INIS)

    Fisher, V.I.; Gregorian, L.; Davara, G.; Kroupp, E.; Bernshtam, V.A.; Ralchenko, Yu. V.; Starobinets, A.; Maron, Y.

    2002-01-01

    Due to important applications, Z-pinches became a subject of extensive studies. In these studies, main attention is directed towards improvement in efficiency of electric energy conversion into high-power radiation burst. At present, knowledge available on physics of Z-pinch operation, plasma motion, atomic kinetics, and energy conversion is mainly knowledge of numerical simulation results. We believe further progress require (i) experimental determination of spatial distribution and time history of thermodynamic parameters and magnetic field, as well as (ii) utilization of this data for experiment-based calculation of r,t-distribution of driving forces, mass and energy fluxes, and local energy deposition rates due to each of contributing mechanisms, what provides an insight into a process of conversion of stored electric energy into radiation burst. Moreover, experimentally determined r, t-distribution of parameters may serve for verification of computer programs developed for simulation of Z-pinch operation and optimization of radiation output. Within this research program we performed detailed spectroscopic study of plasmas imploding in modest-size (25 kV, 5 kJ, 1.2 μs quaterperiod) gas-puff Z-pinch. This facility has reasonably high repetition rate and provides good reproducibility of results. Consistent with plasma ionization degree in the implosion period, measurements are performed in UV-visible spectral range. Observation of spectral lines emitted at various azimuthal angles f showed no dependence on f. Dependence on axial coordinate z is found to be weak in near-anode half of the anode-cathode gap. Based on these observations and restricting the measurements to near-anode half of the gap, an evolution of parameters is studied in time and radial coordinate r only. In present talk we report on determination of radial component of plasma hydrodynamic velocity u r (r,t), magnetic field B ζ (r,t), electron density n e (r,t), density of ions in various

  9. Field reversed theta pinch TC-I UNICAMP

    International Nuclear Information System (INIS)

    Honda, R.Y.; Machida, M.; Aramaki, E.A.; Porto, P.; Berni, L.A.

    1990-01-01

    Field reversed configuration TC-I device is 16 cm diameter, 1 meter long with two mirror coils and 30 kJ field reversed theta pinch working for over two years at University of Campinas. Its implosion dynamics and field reversal parameters have been studied using flux excluded loops, internal magnetic probe, visible spectroscopy, photodiode array and image converter camera. The vacuum vessel is a pyrex tube of 14,5 cm diameter pumped with a liquid nitrogen cooled diffusion pump to a base pressure of 6 x 10 -7 Torr. The schematic view of the machine and experimental set up are shown. (Author)

  10. Reactor advantages of the belt pinch and liquid metal walls

    International Nuclear Information System (INIS)

    Kotschenreuther, M.; Manickam, J.; Menard, J.; Rappaport, H.; Zheng Linjin; Dorland, B.; Miller, R.; Turnbull, A.

    2001-01-01

    MHD stability of highly elongated tokamaks (termed a belt pinch) are considered for high bootstrap fraction cases. By employing high triangularity or indentation, and invoking wall stabilization, and β can be increased by a factor of roughly 3 by increasing κ from 2 to 4. Axisymmetric stability up to κ=4 tolerable by employing a shell which conforms more closely to the boundary than in present experiments. Engineering difficulties with a close fitting shell in a reactor environment may be overcome by employing a liquid lithium alloy shell. Rapid metal flows can lead to potentially deleterious plasma shifts and damping of the flow. (author)

  11. Non ideal instabilities in field reversed O-pinches

    International Nuclear Information System (INIS)

    Santiago, M.A.M.; Gomes, A.S.

    1987-01-01

    Rotational instabilities and resistive tearing modes are the most striking modes observed in high temperature θ-pinches with zero orversed bias field. The configurations which have the effect of a rigid rotation of the plasma column are studied. Some recent experimental data indicate that an m=2 mode appears after the rotation reaches a critical value. It is shown that the growth rate of the m=2 mode may be greater than that of the m=1 resistive kink mode, depending on the experimental conditions. The result are applied to several experimental data in the literature. (author) [pt

  12. Energy confinement in a high-current reversed field pinch

    International Nuclear Information System (INIS)

    An, Z.G.; Lee, G.S.; Diamond, P.H.

    1985-07-01

    The ion temperature gradient driven (eta/sub i/) mode is proposed as a candidate for the cause of anomalous transport in high current reversed field pinches. A 'four-field' fluid model is derived to describe the coupled nonlinear evolution of resistive interchange and eta/sub i/ modes. A renormalized theory is discussed, and the saturation level of the fluctuations is analytically estimated. Transport scalings are obtained, and their implications discussed. In particular, these results indicate that pellet injection is a potentially viable mechanism for improving energy confinement in a high temperature RFP

  13. Bubble Pinch-Off in a Rotating Flow

    DEFF Research Database (Denmark)

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

    2009-01-01

    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...... 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...

  14. Asymmetric flux generation and its relaxation in reversed field pinch

    International Nuclear Information System (INIS)

    Arimoto, H.; Masamune, S.; Nagata, A.

    1985-02-01

    The toroidally asymmetric flux enhancement [''dynamo effect''] and the axisymmetrization of the enhanced fluxes that follows in the setting up phase of Reversed Field Pinch are investigated on the STP-3[M] device. A rapid increase in the toroidal flux generated by the dynamo effect is first observed near the poloidal and toroidal current feeders. Then, this inhomogeneity of the flux propagates toroidally towards the plasma current. The axisymmetrization of the flux is attained just after the maximum of plasma current. The MHD activities decrease significantly after this axisymmetrization and the quiescent period is obtained. (author)

  15. Behaviour of the peripheral plasma in the reversed field pinch

    International Nuclear Information System (INIS)

    Matsuoka, A.; Sato, K.I.; Arimoto, H.; Yamada, S.; Nagata, A.; Murata, H.

    1986-01-01

    By using Langmuir probes installed behind limiters, time behaviour of the peripheral plasma in the Reversed Field Pinch (RFP) are investigated. They are strongly affected by the confined RFP plasma and are divided into three phases (the initial phase before setting up the RFP configuration, the current rising phase, and the quiescent phase), which are just the same as those of the confined RFP plasma. Typical behaviour of the peripheral plasma have relations to the pump out phenomena and of the toroidal flux generation. (author)

  16. Model of emittance growth in a self-pinched beam

    International Nuclear Information System (INIS)

    Lee, E.P.; Yu, S.S.

    1979-01-01

    A semi-phenomenological formula is proposed for the change of emittance of a self-pinched beam which is not matched to its equilibrium radius. Near equilibrium this formula, coupled with an envelope equation, yields the damped sausage oscillations observed in simulation and experiments. For a beam which is injected cold (no transverse velocity spread), the formula coincides with the analytically calculated initial growth of emittance. The basic theory is developed here and used to compute the linear damping rate for several current profiles. The resultant non-linear increase in equilibrium quantities is also calculated in lowest order of the degree of mismatch

  17. Analisis Tingkat Kepentingan Dan Kinerja Layanan Automated Teller Machine (Atm) Bank Mandiri

    OpenAIRE

    Setiawati, Lenny; Sugiharto, Toto

    2008-01-01

    Penelitian ini ditujukan untuk menganalisis tingkat kepentingan dan kinerja layananATM Bank Mandiri. Analisis Servqual yang terdiri atas dimensi tangible, realibility,responsiveness, assurance,dan empathy digunakan untuk menganalisis kinerjalayanan ATM. Sementara itu, Customer Satisfaction Index dan ImportancePerformance Analysis yang terdiri atas analisis kuadran dan analisis kesenjangandigunakan untuk menginvestigasi kepuasan pelanggan dan untuk mengidentifikasikandimensi layanan yang kiner...

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

    International Nuclear Information System (INIS)

    Bliss, David Emery; Vesey, Roger Alan; Rambo, Patrick K.; Lebedev, Sergey V.; Hanson, David L.; Nash, Thomas J.; Yu, Edmund P.; Matzen, Maurice Keith; Afeyan, Bedros B.; 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; Waisman, Eduardo Mario; Mehlhorn, Thomas Alan

    2005-01-01

    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.

  19. Plasma-wall interaction and locked modes in the toroidal pinch experiment TPE-RX reversed-field pinch

    International Nuclear Information System (INIS)

    Pasqualini, D.; Martin, P.; Koguchi, H.; Yagi, Y.; Hirano, Y.; Sakakita, H.; Spizzo, G.

    2006-01-01

    The MHD instabilities that sustain the reversed-field pinch (RFP) configuration tend to phase-lock together and also to wall-lock, forming a bulging of the plasma column, called 'locked mode'. This phenomenon is of particular interest, since the locked mode causes a larger plasma resistivity, plasma cooling, and, in some cases, anomalous discharge termination. Up to now, studies of the locked mode have been focused on m=1 modes (being m the poloidal mode number). In this Letter we show that m=0 modes also play a role, based on the cross-check between magnetic spectra and toroidally resolved D α array measurements. (author)

  20. 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)

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

    International Nuclear Information System (INIS)

    Bustraan, M.; Franken, W.M.P.; Klippel, H.Th.; Veringa, H.J.; Verschuur, K.A.

    1979-10-01

    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

  2. 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.

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

    International Nuclear Information System (INIS)

    Trubnikov, B.A.; Zhdanov, S.K.

    1986-01-01

    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

  4. Anode plasma dynamics in the self-magnetic-pinch diode

    Directory of Open Access Journals (Sweden)

    Nichelle Bruner

    2011-02-01

    Full Text Available The self-magnetic-pinch diode is being developed as an intense electron beam source for pulsed-power-driven x-ray radiography. In high-power operation, the beam electrons desorb contaminants from the anode surface from which positive ions are drawn to the cathode. The counterstreaming electrons and ions establish an equilibrium current. It has long been recognized, however, that expanding electrode plasmas can disrupt this equilibrium and cause rapid reduction of the diode impedance and the radiation pulse. Recently developed numerical techniques, which enable simultaneous modeling of particle currents with 10^{13}  cm^{-3} densities to plasmas of near solid density, are applied to a model of the self-magnetic-pinch diode which includes the formation and evolution of anode surface plasmas. Two mechanisms are shown to cause rapid impedance loss, anode plasma expansion into the anode-cathode (A-K gap, and increased ion space-charge near the cathode surface. The former mechanism dominates for shorter A-K gaps, while the latter dominates for longer gaps. Model results qualitatively reproduce the time-dependent impedances measured for this diode.

  5. Increasing Z-pinch vacuum hohlraum capsule coupling efficiency

    International Nuclear Information System (INIS)

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

    2004-01-01

    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

  6. Confinement in TPE-RX reversed field pinch

    International Nuclear Information System (INIS)

    Yagi, Y.; Bolzonella, T.; Canton, A.

    2001-01-01

    Characteristics of the confinement properties of a reversed field pinch (RFP), the TPE-RX (R/a=1.72/0.45 m, R and a are major and minor radii), are presented for the plasma current, I p of 0.2-0.4 MA. TPE-RX has been operational since 1998, and I p =0.5 MA and duration time of up to 0.1 s have been obtained separately. It is found that I p /N (=12x10 -14 Am, N is the line density) is higher than those of other RFPs and poloidal beta, β p , and energy confinement time, τ E , are 5-10% and 0.5-1 ms, respectively, which are comparable with those of other RFPs of comparable sizes (RFX and MST). Pulsed poloidal current drive has recently been tested and the result has shown a twofold improvement of β p and τ E . The improvement is discussed in terms of the dynamic trajectories in the F-Θ plane, where F and Θ are reversal and pinch parameters, respectively. The global confinement properties are compared between the locked and non-locked discharges, which yields a better understanding of the mode-locking phenomena in RFP plasmas. (author)

  7. 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

  8. Analisis SWOT Implementasi Tekonologi Finansial terhadap Kualitas Layanan Perbankan di Indonesia

    Directory of Open Access Journals (Sweden)

    Imanuel Adhitya Wulanata Chrismastianto

    2017-04-01

    Menyikapi realisasi era digital saat ini, kualitas layanan perbankan di Indonesia diharapkan semakin meningkat secara signifikan, agar mampu menjangkau seluruh lapisan masyarakat, khususnya bagi masyarakat yang tinggal di daerah 3T (Terdepan, Terluar, dan Terpencil. Namun, pada kenyataannya kualitas layanan perbankan di Indonesia saat ini masih minim dalam mengakses masyarakat yang tinggal di daerah 3T tersebut. Mencermati berbagai realita yang telah diuraikan di atas, maka melalui analisis SWOT implementasi kebijakan teknologi finansial ini, diharapkan kualitas layanan perbankan semakin dapat ditingkatkan dan dirasakan oleh seluruh lapisan masyarakat Indonesia secara riil dan para pelaku perbankan dapat memahami pengelolaan fungsi manajemen perbankan dengan tepat didasarkan pada sikap takut akan Tuhan dan menghargai sesama, dalam konteks pengelolaan aset internal maupun eksternal yang mencakup aktivitas perbankan secara holistik. Dengan demikian, tulisan ini bertujuan untuk menganalisis secara lebih mendalam mengenai kekuatan, kelemahan, peluang, dan ancaman (SWOT implementasi teknologi finansial terhadap kualitas layanan perbankan Indonesia di era digital melalui studi literatur perbankan.

  9. Development of a Z-pinch-driven ICF hohlraum concept on Z

    International Nuclear Information System (INIS)

    Cuneo, M.E.; Porter, J.L. Jr.; Vesey, R.A.

    1999-01-01

    Recent development of high power z-pinches (> 150 MW) on the Z driver has permitted the study of high-temperature, radiation-driven hohlraums. Three complementary, Z-pinch source-hohlraum-ICF capsule configurations are being developed to harness the x-ray output of these Z-pinch's. These are the dynamic-hohlraum, static-wall hohlraum, and Z-pinch-driven hohlraum concepts. Each has different potential strengths and concerns. In this paper, the authors report on the first experiments with the Z-pinch-driven hohlraum (ZPDH) concept. A high-yield ICF capsule design for this concept appears feasible, when driven by z-pinches from a 60 MA-class driver. Initial experiments characterize the behavior of the spoke array on Z-pinch performance and x-ray transmission, and the uniformity of radiation flux incident on a foam capsule in the secondary, for a single-sided drive. Measurements of x-ray wall re-emission power and spectrum, radiation temperatures, spoke-plasma location, and drive uniformity will be presented and compared with 0-D energetics, 2-D Lasnex rad-hydro, and 3-D radiosity calculations of energy transport and drive uniformity

  10. Development of a Z-pinch-driven ICF hohlraum concept on Z

    Energy Technology Data Exchange (ETDEWEB)

    Cuneo, M E; Porter, Jr, J L; Vesey, R A [and others

    1999-07-01

    Recent development of high power z-pinches (> 150 MW) on the Z driver has permitted the study of high-temperature, radiation-driven hohlraums. Three complementary, Z-pinch source-hohlraum-ICF capsule configurations are being developed to harness the x-ray output of these Z-pinch's. These are the dynamic-hohlraum, static-wall hohlraum, and Z-pinch-driven hohlraum concepts. Each has different potential strengths and concerns. In this paper, the authors report on the first experiments with the Z-pinch-driven hohlraum (ZPDH) concept. A high-yield ICF capsule design for this concept appears feasible, when driven by z-pinches from a 60 MA-class driver. Initial experiments characterize the behavior of the spoke array on Z-pinch performance and x-ray transmission, and the uniformity of radiation flux incident on a foam capsule in the secondary, for a single-sided drive. Measurements of x-ray wall re-emission power and spectrum, radiation temperatures, spoke-plasma location, and drive uniformity will be presented and compared with 0-D energetics, 2-D Lasnex rad-hydro, and 3-D radiosity calculations of energy transport and drive uniformity.

  11. A Reactor Development Scenario for the FUZE Shear-flow Stabilized Z-pinch

    Science.gov (United States)

    McLean, H. S.; Higginson, D. P.; Schmidt, A.; Tummel, K. K.; Shumlak, U.; Nelson, B. A.; Claveau, E. L.; Golingo, R. P.; Weber, T. R.

    2016-10-01

    We present a conceptual design, scaling calculations, and a development path for a pulsed fusion reactor based on the shear-flow-stabilized Z-pinch device. Experiments performed on the ZaP device have demonstrated stable operation for 40 us at 150 kA total discharge current (with 100 kA in the pinch) for pinches that are 1cm in diameter and 100 cm long. Scaling calculations show that achieving stabilization for a pulse of 100 usec, for discharge current 1.5 MA, in a shortened pinch 50 cm, results in a pinch diameter of 200 um and a reactor plant Q 5 for reasonable assumptions of the various system efficiencies. We propose several key intermediate performance levels in order to justify further development. These include achieving operation at pinch currents of 300 kA, where Te and Ti are calculated to exceed 1 keV, 700 kA where fusion power exceeds pinch input power, and 1 MA where fusion energy per pulse exceeds input energy per pulse. This work funded by USDOE ARPAe ALPHA Program and performed under the auspices of Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-697801.

  12. Waste Management Pinch Analysis (WAMPA): Application of Pinch Analysis for greenhouse gas (GHG) emission reduction in municipal solid waste management

    International Nuclear Information System (INIS)

    Ho, Wai Shin; Hashim, Haslenda; Lim, Jeng Shiun; Lee, Chew Tin; Sam, Kah Chiin; Tan, Sie Ting

    2017-01-01

    Highlights: • A novel method known as Waste Management Pinch Analysis (WAMPA) is presented. • WAMPA aims to identify waste management strategies based on specific target. • WAMPA is capable to examine the capacity of waste management strategies through graphical representation. - Abstract: Improper waste management happened in most of the developing country where inadequate disposal of waste in landfill is commonly practiced. Apart from disposal, MSW can turn into valuable product through recycling, energy recovery, and biological recovery action as suggested in the hierarchy of waste management. This study presents a method known as Waste Management Pinch Analysis (WAMPA) to examine the implication of a dual-objective – landfill and GHG emission reduction target in sustainable waste management. WAMPA is capable to identify the capacity of each waste processing strategy through graphical representation. A general methodology of WAMPA is presented through a demonstration of a SWM case followed by a detailed representation of WAMPA for five waste types. Application of the WAMPA is then applied on a case study for sustainable waste management planning from year 2015 to 2035. Three waste management strategies are incorporated into the case study – landfill, Waste-to-Energy (WtE), and reduce, reuse, and recycle (3R). The results show a 13.5% of total GHG emission reduction and 54.6% of total reduction of landfill are achieved. The major contributor of GHG emission which are from food waste (landfill emission) and plastic (WtE emission) is reduced.

  13. ANALYSIS OF POWER GRIP AND PINCH GRIP AMONG HEALTH CARE PROFESSIONALS

    Directory of Open Access Journals (Sweden)

    Zakariya M P

    2016-02-01

    Full Text Available Background: Grip and pinch strength are commonly employed indices of strength used in hand evaluations. Pinch grip and power grip strengths are used as indices of strength in hand therapy assessments. For all professions grip strength is an important criterion to be successful in their profession. Such phenomena may be explained by differences in nature of work, working environment, and objects workers handle. Method: 200 healthy subjects, satisfying the selection criteria were included and assessed with standardized procedure for power grip and pinch grip (lateral pinch, pad-pad, and tip-tip strength. They were divided in four groups, 50 group each according to profession i.e. medical surgeons, dentist, physiotherapists and nurses. Results: The mean power grip strength shows highly significant difference between medical vs. dental (p>0.01 and medical vs. physiotherapy group (p> 0.05 .The mean lateral pinch strength shows there is highly significant difference (p< 0.001 between dental vs. nursing profession and dental vs. physiotherapy group. No significant difference among other groups. The mean pad-pad pinch strength shows there is significant difference between dental vs. nursing (p< 0.05 and dental vs physiotherapy group (p< 0.05. The mean Tip-Tip pinch strength shows there is significant difference between dental vs nursing profession(p< 0.05 and dental vs. physiotherapy(p< 0.05. No significant different among other groups. Conclusion: Surgeons have highest power grip strength followed by Nursing, Physiotherapy and Dental professionals. Dentists have the maximum pinch strength in all three positions, followed by Surgeons, Nurses and Physiotherapists. Surgeons have maximum pinch strength next to Dentists.

  14. ANALISIS VARIABILITAS CURAH HUJAN DAN SUHU DI BALI

    Directory of Open Access Journals (Sweden)

    Ogi Setiawan

    2017-01-01

    Full Text Available Indonesia sebagai negara kepulauan yang terdiri dari pulau-pulau besar dan kecil menjadi sangat rentan terhadap dampak perubahan iklim. Salah satu pulau yang juga rentan terhadap perubahan iklim adalah pulau Bali. Dampak potensial adanya perubahan iklim adalah perubahan pola hujan, peningkatan suhuudaradankenaikanpermukaanlaut. Sektoryangakanmenerimadampakperubahaniklimdengan serius adalah sektor kehutanan dan pertanian. Untuk mendukung upaya mitigasi dan adaptasi maka diperlukan informasi perubahan iklim yang terjadi. Penelitian ini bertujuan untuk mengetahui variabilitas iklim di Bali. Metode yang digunakan adalah analisis kecenderungan curah hujan, analisis perubahan suhu udara, analisis perubahan tipe iklim dan analisis pergeseran bulan basah, lembab dan kering. Data hujan yang digunakan adalah data hujan dari GPCC (1961-1998 dan BMKG Bali (19992008, sedangkan data suhu berasal dari BMKG Bali (2004-2008. Hasil analisis menunjukkan bahwa di pulau Bali secara umum sudah mengalami perubahan iklim. Tipe iklim berdasarkan Schmidt-Ferguson mengalami perubahan dari relatif basah menjadi agak kering. Suhu udara rata-rata bulanan serta curah hujan bulanan dan tahunan memiliki kecenderungan yang semakin meningkat. Bulan basah dan bulan kering telah mengalami pergeseran dan perubahan jumlahnya. Dampak perubahan iklim terhadap ekosistem hutan di Bali belum diketahui dengan pasti, namun terdapat beberapa implikasi perubahan iklim terhadap sektor kehutanan diantaranya kebakaran hutan dan perubahan jadwal penanaman.

  15. 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)

    1993-12-31

    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

  16. 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

  17. The belt-screw-pinch reactor and other high-beta systems

    International Nuclear Information System (INIS)

    Bustraan, M.; Klippel, H.Th.; Veringa, H.J.; Verschuur, K.A.

    1981-01-01

    In a screw-pinch reactor the expenditure for plasma implosion and compression can be reduced and the reacting volume and burn time can be enlarged. This is possible by pinch ignition of only a few percent of the fuel. Fusion energy then ignites injected fuel pellets and expands the plasma. The magnitude of the pulsed magnetic fields is such as to make the application of superconducting coils feasible. An economical reactor model is described. A comparison is made with tokamak and reversed field pinch reactor designs. (author)

  18. The belt pinch - a high-β tokamak with non-circular cross-section

    International Nuclear Information System (INIS)

    Gruber, O.; Peiry, J.M.; Wilhelm, R.

    1975-10-01

    The stability behaviour of non-circular plasma cross-sections is discussed on the basis of present known theory. Then the technical arrangement and the preionization of the Belt Pinch is described. The following section deals with the establishment of the non-circular equilibrium and summarizes the essential plasma paramters and the used diagnostic methods. The stability properties of the Belt Pinch, lead to a critical q-value. Finnaly, supporting experiments for the future Belt Pinch programm are presented. (orig./GG) [de

  19. The effect of magnetic field configuration on particle pinch velocity in compact helical system (CHS)

    International Nuclear Information System (INIS)

    Iguchi, H.; Ida, K.; Yamada, H.

    1994-01-01

    Radial particle transport has been experimentally studied in the low-aspect-ratio heliotron/torsatron device CHS. A non-diffusive outward particle flow (inverse pinch) is observed in the magnetic configuration with the magnetic axis shifted outward, while an inward pinch, like in tokamaks, is observed with the magnetic axis shifted inward. This change in the direction of anomalous particle flow is not due to the reversal of temperature gradient nor the radial electric field. The observation suggests that the particle pinch velocity is sensitive to the magnetic field structure. (author)

  20. Electron-Cloud Pinch Dynamics in Presence of Lattice Magnet Fields

    CERN Document Server

    Franchetti, G

    2011-01-01

    The pinch of the electron cloud due to a passing proton bunch was extensively studied in a field free region and in a dipolar magnetic field. For the latter study, a strong field approximation helped to formulate the equations of motion and to understand the complex electron pinch dynamics, which exhibited some similarities with the field-free situation. Here we extend the analysis to the case of electron pinch in quadrupoles and in sextupoles. We discuss the limits of validity for the strong field approximation and we evaluate the relative magnitude of the peak tune shift along the bunch expected for the different fields.

  1. Investigation of layered Z-pinches on ANGARA-5-1

    Energy Technology Data Exchange (ETDEWEB)

    Branitskij, A V; Grabovskij, E V; Zakharov, S V; Zurin, M V; Nedoseev, S L; Olejnik, G M; Smirnov, V P; Frolov, I N [Troitsk Inst. of Innovative and Fusion Research (Russian Federation)

    1997-12-31

    Experimental results of layered Z-pinch investigations on Angara-5-1 are presented. The level of current was 3-4 MA through a load with a 70-90 ns rise time. The initial-to-final radius ratio increased from 10-15 for a conventional single pinch, up to 30-50 for the double layered design. A power flux of about 8-12 TW/cm{sup 2} was achieved with front rise time about 3 ns. The final pinch diameter was down to 0.5-1 mm. (author). 4 figs., 1 ref.

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

    International Nuclear Information System (INIS)

    Pedrow, P.D.; Nasiruddin, A.M.

    1989-01-01

    Langmuir probe, photodiode, and optical multichannel analyzer (OMA) measurements have been made on a pulsed CF 4 conical theta pinch plasma. A cloud of CF 4 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

  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. Performance improvement of centrifugal compressor stage with pinched geometry or vaned diffuser

    Energy Technology Data Exchange (ETDEWEB)

    Jaatinen, A.

    2009-07-01

    Centrifugal compressors are widely used for example in refrigeration processes, the oil and gas industry, superchargers, and waste water treatment. In this work, five different vaneless diffusers and six different vaned diffusers are investigated numerically. The vaneless diffusers vary only by their diffuser width, so that four of the geometries have pinch implemented to them. Pinch means a decrease in the diffuser width. Four of the vaned diffusers have the same vane turning angle and a different number of vanes, and two have different vane turning angles. The flow solver used to solve the flow fields is Finfo, which is a Navier-Stokes solver. All the cases are modeled Chien's k-epsilon turbulence model. All five vaneless diffusers and three vaned diffusers are investigated also experimentally. For each construction, the compressor operating map is measured according to relevant standards. In addition to this, the flow fields before and after the diffuser are measured with static and total pressure, flow angle and total temperature measurements k-omega SST turbulence model. The simulation results indicate that it is possible to improve the efficiency with the pinch, and according to the numerical results, the two best geometries are the ones with most pinch at the shroud. These geometries have approximately 4 percentage points higher effciency than the unpinched vaneless diffusers. The hub pinch does not seem to have any major benefits. In general, the pinches make the flow fields before and after the diffuser more uniform. The pinch also seems to improve the impeller effciency. This is down to two reasons. The major reason is that the pinch decreases the size of slow flow and possible backflow region located near the shroud after the impeller. Secondly, the pinches decrease the flow velocity in the tip clearance, leading to a smaller tip leakage flow and therefore slightly better impeller efficiency. Also some of the vaned diffusers improve the efficiency

  5. 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)

    DERZON, MARK S.

    2000-01-01

    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

  6. Dynamical determination of ohmic states of a cylindrical pinch

    International Nuclear Information System (INIS)

    Schnack, D.D.

    1980-04-01

    The dual problems of generation and sustainment of the reversed axial field are studied. It is shown that, if a cylindrical plasma is initially in an axisymmetric state with a sufficient degree of paramagnetism, field reversal can be attained by mode activity of a single helicity. The initial paramagnetism may be due to the method of pinch formation, as in fast experiments, or to a gradual altering of the pitch profile resulting from a succession of instabilities. Furthermore, if the total current is kept constant and energy loss and resistivity profiles are included in an ad hoc manner, one finds that the final steady state of the helical instability can be maintained for long times against resistive diffusion without the need for further unstable activity. These states, which possess zero order flow and possibly reversed axial field, represent steady equilibria which simultaneously satisfy force balance and Ohm's law, and are termed Ohmic states

  7. Oscillating field current drive for reversed field pinch discharges

    International Nuclear Information System (INIS)

    Schoenberg, K.F.; Gribble, R.F.; Baker, D.A.

    1984-06-01

    Oscillating Field Current Drive (OFCD), also known as F-THETA pumping, is a steady-state current-drive technique proposed for the Reversed Field Pinch (RFP). Unlike other current-drive techniques, which employ high-technology, invasive, and power intensive schemes using radio frequency or neutral particle injection, F-THETA pumping entails driving the toroidal and poloidal magnetic field circuits with low-frequency (audio) oscillating voltage sources. Current drive by this technique is a consequence of the strong nonlinear plasma coupling in the RFP. Because of its low frequency and efficient plasma coupling, F-THETA pumping shows excellent promise as a reactor-relevant current-drive technique. A conceptual and computational study of this concept, including its experimental and reactor relevance, is explored in this paper

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

    International Nuclear Information System (INIS)

    Hagenson, R.L.; Krakowski, R.A.

    1980-01-01

    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

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

    International Nuclear Information System (INIS)

    Bertschinger, G.

    1980-01-01

    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 10 24 m -3 with an electron temperature of about 1.2 x 10 5 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) [de

  10. 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.

  11. LTPF: a linear theta-pinch neutron source

    International Nuclear Information System (INIS)

    Ellis, W.R.

    1975-07-01

    The linear theta pinch is optimized with respect to maximum neutron current on a sample located between the discharge tube and the compression coil wall. Emphasis throughout is placed on physics and technology considerations which govern the choice of parameters. Technological demands are (hopefully) kept to a minimum. Two ''point designs'' are developed which are distinguished by their compressional magnetic field (i.e., coil current) wave-forms: one is sinusoidal and continuous, the other trapezoidal and pulsed intermittently. Both point designs give an average neutron current of approximately 5 x 10 13 n/cm 2 /s. Both devices are characterized by short lengths (approximately 1 m), rapid cycling (2 to 30 kHz), and magnetic mirrors (2 to 5:1) at the ends. A crucial item is the power supply, which is discussed in detail. (U.S.)

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

    International Nuclear Information System (INIS)

    Glasser, A.H.; Nebel, R.A.

    1989-01-01

    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

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

    International Nuclear Information System (INIS)

    Glasser, A.H.; Nebel, R.A.

    1989-01-01

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

    International Nuclear Information System (INIS)

    Hagenson, R.L.; Krakowski, R.A.

    1981-10-01

    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

  15. Divertor design for the TITAN reversed-field-pinch reactor

    International Nuclear Information System (INIS)

    Cooke, P.I.H.; Bathke, C.G.; Blanchard, J.P.; Creedon, R.L.; Grotz, S.P.; Hasan, M.Z.; Orient, G.; Sharafat, S.; Werley, K.A.

    1987-01-01

    The design of the toroidal-field divertor for the TITAN high-power-density reversed-field-pinch reactor is described. The heat flux on the divertor target is limited to acceptable levels (≤ 10 MW/m 2 ) for liquid-lithium cooling by use of an open divertor geometry, strong radiation from the core and edge plasma, and careful shaping of the target surface. The divertor coils are based on the Integrated-Blanket-Coil approach to minimize the loss in breeding-blanket coverage due to the divertor. A tungsten-rhenium armour plate, chosen for reasons of sputtering resistance, and good thermal and mechanical properties, protects the vanadium-alloy coolant tubes

  16. Cost estimation for a theta-pinch reactor

    International Nuclear Information System (INIS)

    Coultas, T.A.; Cook, J.M.; Crnkovich, P.; Dauzvardis, P.

    1976-02-01

    A simulation of a theta-pinch fusion power plant has been completed to the point where economic feasibility can be examined. A PL/I cost subprogram is presented for interfacing with the computer code TPFPP. This code is then used to obtain a first approximation of the costs for the reactor. Independent geometrical and plant design parameters are varied over a wide range, with simultaneous variation of magnetic field, minor first wall radius, and plasma maximum compression. The study indicates that the plant energy balance must be favorable, availability must be high, and major component costs must be low to achieve economical results. Although costing uncertainties remain, it is clear that development of easy and rapid replacement methods for reactor components is essential and that new staging concepts to reduce the implosion energy requirement must be pursued

  17. 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.

  18. Imploding to equilibrium of helically symmetric theta pinches

    International Nuclear Information System (INIS)

    Sharky, N.N.

    1978-01-01

    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

  19. Magnetohydrodynamic effects of current profile control in reversed field pinches

    International Nuclear Information System (INIS)

    Sovinec, C.R.; Prager, S.C.

    1999-01-01

    Linear and non-linear MHD computations are used to investigate reversed field pinch configurations with magnetic fluctuations reduced through current profile control. Simulations with reduced ohmic drive and moderate auxiliary current drive, represented generically with an electron force term, applied locally in radius near the plasma edge show magnetic fluctuation energies that are orders of magnitude smaller than those in simulations without profile control. The core of the improved configurations has reduced magnetic shear and closed flux surfaces in some cases, and reversal is sustained through the auxiliary current drive. Modes resonant near the edge may become unstable with auxiliary drive, but their saturation levels can be controlled. The space of auxiliary drive parameters is explored, and the ill effects of deviating far from optimal conditions is demonstrated in non-linear simulations. (author)

  20. Catalyzed deuterium fueled reversed-field pinch reactor assessment

    International Nuclear Information System (INIS)

    Dobrott, D.

    1985-01-01

    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

  1. A vented pump limiter for the reversed field pinch RFX

    International Nuclear Information System (INIS)

    Sonato, P.

    1998-01-01

    The reversed field pinch (RFP) plasma performance, as in the Tokamak, is strongly correlated with the edge neutral particle control. The drawbacks of the conventional magnetic divertors and throat limiters on the RFP plasma have slackened the application of an active particle control system in existing devices. An advanced solution, based on the idea of the 'vented pump limiter' experimented on Tore Supra, has been conceived for RFX. This type of pump limiter is very attractive for a RFP. In this paper, the design of a 'vented limiter' prototype for RFX is presented. Up to six modules of this limiter can be installed at the equatorial plane of RFX, allowing a particle exhaust efficiency comparable with a divertor or a throat limiter working in a Tokamak. Finally, the optimization of this concept for the next step RFP device is presented. (orig.)

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

    International Nuclear Information System (INIS)

    Armstrong, W.T.

    1978-06-01

    Prompt stimulated Brillouin scatter (SBS) is studied in an experiment wherein a high power, pulsed CO 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 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

  3. Ohmic heating of the reversed-field pinch

    International Nuclear Information System (INIS)

    Gerwin, R.

    1980-04-01

    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

  4. Pinches and micropinches in the SPEED 2 plasma focus

    Energy Technology Data Exchange (ETDEWEB)

    Roewekamp, P; Decker, G; Kies, W; Lucas, B; Schmitz, F; Ziethen, G [Heinrich-Heine-Univ., Duesseldorf (Germany). Institut fuer Experimentalphysik; Simanovskij, D M; Bobashev, S V [Russian Academy of Sciences, St. Petersburg (Russian Federation). A.F. Ioffe Physico-Technical Inst.

    1997-12-31

    The discharges in the SPEED 2 Plasma Focus as well as other pinch plasmas generated in a plasma focus configuration exhibit two different modes. The micropinch mode is experimentally investigated in detail and well theoretically modelled. Therefore its characteristics e.g. temperature, density, life time and energy output are well known. Nevertheless the micropinches appear very erratic in space and time and their optimization and application is rather difficult. In contrast to this the column mode is not equally well understood yet. Its remarkable features are the unexpectedly high stability (also if the critical current for radiative collapse is exceeded) and its reproducibility, which are important for applications in soft x-ray microscopy or lithography. (J.U.). 6 figs., 9 refs.

  5. Turbulent transport in the MST reversed-field pinch

    International Nuclear Information System (INIS)

    Rempel, T.D.; Almagri, A.F.; Assadi, S.; Den Hartog, D.J.; Hokin, S.A.; Prager, S.C.; Sarff, J.S.; Shen, W.; Sidikman, K.L.; Spragins, C.W.; Sprott, J.C.; Stoneking, M.R.; Zita, E.J.

    1991-11-01

    Measurements of edge turbulence and the associated transport are ongoing in the Madison Symmetric Torus (R = 1.5 m, a = 0.52 m) reversed-field pinch using magnetic and electrostatic probes. Magnetic fluctuations are dominated by m = 1 and n ∼ 2R/a tearing modes. Particle losses induced by magnetic field fluctuations have been found to be ambipolar ( parallel B r > = O). Electrostatic fluctuations are broadband and turbulent, with mode widths δm ∼ 3--7 and δn ∼70--150. Particle, parallel current, and energy transport arising from coherent motion with the fluctuating ExB drift has been measured. Particle transport via this channel is comparable to the total particle loss from MST. Energy transport (from phi >/B o ) due to electrostatic fluctuations is relatively small, and parallel current transport (from parallel E chi >/B o ) may be small as well

  6. Interferometry and MHD turbulence measurements in toroidal pinches

    International Nuclear Information System (INIS)

    Dutt, T.L.; Evans, D.E.; Wilcock, P.D.

    1976-01-01

    A 10.6 micron interferometer produced 2 to 3 good quality fringes in the HBTX plasma. There is substantial agreement in the electron densities determined by interferometry and by Thomson scattering, but since the former is an absolute measurement and is systematically lower than the Thomson scattering values, the latter may be too great by about 35%. In RF Pinches, turbulence associated with the instability deflects the beam and corrupts the interferogram. However, if the intensity fluctuations induced in this beam by the turbulence, are measured, as is done in the second experiment performed in the FRSX plasma with a HCN laser, the frequency spectrum of the turbulence can be deduced. In this plasma, rms fluctuations in the density were measured by this means to be 20%, and the dominant frequency of the fluctuations multiplied by the tube diameter was approximately Alfven speed, favouring an interpretation of the gross turbulence in this plasma in terms of Alfen waves. (U.K.)

  7. Simulation of the implosion of a theta pinch

    International Nuclear Information System (INIS)

    Busnardo Neto, J.; Leite Neto, J.P.; Jesus Paes, A.C. de

    1982-01-01

    A two-fluid model was used to simulate the implosion of a theta-pinch, with initial densities varying from 10 12 to 10 16 cm -3 . The gases used were hydrogen, helium, neon and argon; initial temperatures of 2 eV and total ionization were assumed. For hydrogen the anomalous resistivity is dominant everywhere when the density is low (ν sub(eff) - ω sub(pi)). For high densities both resistivities are not high enough to allow diffusion of the magnetic field during the time of the implosion (ν sub(eff) approximatelly 0.3 ω sub(pi)). For heavier gases a surprisingly high value of the anomalous resistivity was found, due to the greater mass, (ν sub(eff) approximatelly 10-12 ω sub(pi)). (Author) [pt

  8. Physics of reversed-field pinch profile sustainment

    International Nuclear Information System (INIS)

    Moses, R.W.

    1984-01-01

    A description of the Reversed-Field Pinch (RFP) is given, emphasizing the necessity of a magnetohydrodynamic (MHD) or kinetic process to sustain field reversal. Three sustainment mechanisms are reviewed: the MHD dynamo, the tangled discharge model, and nonlocal resistivity. A slab model of steady (ohmic) states is described. A relationship between ohmic state wave numbers and the minimum amplitude of nonsymmetric field components is given. If ohmic states are the sole source of the sustainment process, their wave lengths are probably much longer than the minor diameter of the plasma. Otherwise field asymmetries would exceed those observed in experiments. It is noted that internal field data are still limited, restricting the generality of our comments

  9. Phenomenological modeling of argon Z-pinch implosions

    International Nuclear Information System (INIS)

    Whitney, K.G.; Thornhill, J.W.; Deeney, C.; LePell, P.D.; Coulter, M.C.

    1992-01-01

    The authors investigate some of the effects of plasma turbulence on the K-shell emission dynamics of argon gas puff Z-pinch implosions. The increases that turbulence produces in the plasma viscosity, heat conductivity, and electrical resistivity are modeled phenomenologically using multipliers for these quantities in the MHD calculations. The choice of multipliers was made by benchmarking a 1-D MHD simulation of a Physics International Inc. argon gas puff experiment against the inferred densities and temperatures achieved in the experiment. These multipliers were then used to study the parametric dependence of the K-shell emission on the energy input to the argon plasma for a fixed mass loading. Comparisons between turbulent and non-turbulent argon implosions are made

  10. Instability heating of solid-fiber Z pinches

    International Nuclear Information System (INIS)

    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 2 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

  11. Instability heating of solid-fiber Z pinches

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Jr., Ronald Alan [Univ. of California, San Diego, CA (United States)

    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 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.

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

    International Nuclear Information System (INIS)

    Erckmann, V.

    1983-02-01

    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) [de

  13. Charger 1: A New Facility for Z-Pinch Research

    Science.gov (United States)

    Taylor, Brian; Cassibry, Jason; Cortez, Ross; Doughty, Glen; Adams, Robert; DeCicco, Anthony

    2017-01-01

    Charger 1 is a multipurpose pulsed power laboratory located on Redstone Arsenal, with a focus on fusion propulsion relevant experiments involving testing z-pinch diodes, pulsed magnetic nozzle and other related physics experiments. UAH and its team of pulsed power researchers are investigating ways to increase and optimize fusion production from Charger 1. Currently the team has reached high-power testing. Due to the unique safety issues related to high power operations the UAH/MSFC team has slowed repair efforts to develop safety and operations protocols. The facility is expected to be operational by the time DZP 2017 convenes. Charger 1 began life as the Decade Module 2, an experimental prototype built to prove the Decade Quad pinch configuration. The system was donated to UAH by the Defense Threat Reduction Agency (DRTA) in 2012. For the past 5 years a UAH/MSFC/Boeing team has worked to refurbish, assemble and test the system. With completion of high power testing in summer 2017 Charger 1 will become operational for experimentation. Charger 1 utilizes a Marx Bank of 72 100-kV capacitors that are charged in parallel and discharged in series. The Marx output is compressed to a pulse width of approximately 200 ns via a pulse forming network of 32 coaxial stainless steel tubes using water as a dielectric. After pulse compression a set of SF6 switches are triggered, allowing the wave front to propagate through the output line to the load. Charger 1 is capable of storing 572-kJ of energy and time compressing discharge to less than 250 ns discharge time producing a discharge of about 1 TW of discharge with 1 MV and 1 MA peak voltage and current, respectively. This capability will be used to study energy yield scaling and physics from solid density target as applied to advanced propulsion research.

  14. ANALISIS SPASIAL KEJADIAN DEMAM BERDARAH DENGUE BERDASARKAN KEPADATAN PENDUDUK

    Directory of Open Access Journals (Sweden)

    Agcrista Permata Kusuma

    2016-01-01

    Full Text Available Abstrak Puskesmas Kedungmundu merupakan wilayah endemis DBD dengan kasus yang tinggi. Diperlukan upaya dalam menentukan kebijakan strategi pengendalian vektor secara efektif dan efisien. Analisis spasial dalam SIG dapat digunakan untuk mengetahui pola penyebaran dan daerah potensi penularan DBD. Jenis penelitian ini adalah penelitian deskriptif analitik menggunakan pendekatan cross sectional. Teknik pengambilan sampel menggunakan sampel wilayah memperhatikan proporsi sampel dengan jumlah sampel 146 responden. Pengambilan titik koordinat menggunakan GPS. Analisis data menggunakan analisis univariat dan analisis spasial. Hasil perhitungan statistik spasial ANN diperoleh nilai Z-score = -11,054 terdapat pola spasial kasus DBD di wilayah kerja Puskesmas Kedungmundu. Nilai ANN = 0,52 < 1, artinya pola penyebaran kejadian DBD yang terjadi adalah berkerumun. Kesimpulan dalam penelitian ini sebaran kasus DBD memiliki keterkaitan secara spasial dengan kepadatan penduduk. Abstract Kedungmundu PHC is an endemich region with a high case. Be required to determine policy of vector control strategies effectively and efficiently. Spatial analsys in GIS can be used to determine the pattern of distribution and areas of DHF potential transmission. The type this research was analysis descriptive with cross sectional approach. The sampling technique used a sample area of attention to the proportion of the sample with 146 respondents of total sample. Capturing the coordinates used GPS. Data analisys used univariat and spatial analisys. Result of ANN obtained a Z-score= -11,054, there was a spatial pattern of dengue cases in Kedungmundu PHC. ANN value = 0,52 < 1, it meant that the pattern of DHF distribution was clustered. The conclution of this research was DHF distribution cases has spatial correlation with density population.

  15. 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

  16. Analisis Kelayakan Finansial Usaha Budidaya Bambu

    Directory of Open Access Journals (Sweden)

    Husnul Khotimah

    2015-12-01

    Full Text Available Budidaya bambu diperlukan untuk menambah populasi bambu yang cenderung berkurang yang disebabkan oleh beralihnya fungsi lahan yang digunakan untuk pemukiman atau diganti dengan komoditi tanaman lain yang dianggap lebih menguntungkan. Sementara itu kebutuhan bahan baku bambu terus meningkat sejalan dengan pertumbuhan penduduk dan perkembangan kemajuan ilmu pengetahuan. Budidaya bambu bermanfaat selain untuk menjaga ketersediaan suplai juga untuk meningkatkan kualitas bambu untuk memenuhi permintaan pasar. Tulisan ini mengkaji analisis finansial dari penanaman bambu. Kajian finansial dibutuhkan untuk menunjukkan bahwa upaya penanaman atau budidaya bambu ini layak atau tidak secara finansial untuk dilakukan. Data yang digunakan adalah data hasil penelitian di perusahaan perkebunan bambu PT XYZ di Lampung. Hasil penelitian menunjukkan bahwa nilai NPV (Rp 36.644.364,08 lebih besar dari nol, Net B/C (2,56 lebih besar dari satu, IRR (11 % lebih besar dari suku bunga 6 %, serta payback period pada tahun ke-9 umur proyek 15 tahun. Berdasarkan kriteria indikator kelayakan finansial dapat disimpulkan bahwa usaha budidaya bambu layak secara finansial untuk diusahakan. Katakunci: Hasil Hutan Bukan Kayu (HHBK, budidaya bambu, studi kelayakan, analisis finansial   Financial analysis and feasibity study of bamboo cultivation  Abstract Bamboo cultivation is necessary to increase the population of bamboo clumps. The bamboo clumps tend to decrease due to the shift of used lands for residential or replaced by other crop comodities, which are considered more profitable. On the other hand, the need of bamboo for raw materials remain increase in line with population growth and the development of science. The important of the bamboo cultivation are to maintain the availability of its supply and to improve the quality of bamboo, which meet the market demands. This paper examined financial analysis of bamboo cultivation. Financial study was necessary to show whether

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

    International Nuclear Information System (INIS)

    Singh, R.; Weiland, J.

    1989-01-01

    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.)

  18. Statistical theory of field fluctuations in a reversed-field pinch

    International Nuclear Information System (INIS)

    Turner, L.

    1982-01-01

    A statistical description of three-dimensional, incompressible turbulence in an ideal, current-bearing, bounded magnetofluid is given both analytically and numerically. Our results are then compared with existing data taken from reversed-field pinch experiments

  19. A tentative opinion of modeling plasma formation in metallic wire Z pinch

    International Nuclear Information System (INIS)

    Ding Ning

    2002-01-01

    Numerous experiments in both single wire and in wire arrays have attracted much attention. For the wire array Z-pinch implosions the plasma formation in the metallic wire Z pinches is a key question. By means of analyzing a number of single-wire and multi-wire experiments, two models to describe the behavior of a wire array Z-pinch in initial phase are suggested. In this phase each wire carries a rising current and behaves independently in a way similar to that found in single wire Z-pinch experiments in which a comparable current in one wire is employed. Based on one- or/and two-dimensional magnetohydrodynamics (MHD) theory, one model is used to simulate the electrical explosion stage of the metallic wire, another is used to simulate the wire-plasma formation stage

  20. Experimental studies of the argon-puff Z-pinch implosion process

    International Nuclear Information System (INIS)

    Huang Xianbin; Yang Libing; Gu Yuanchao; Deng Jianjun; Zhou Rongguo; Zou Jie; Zhou Shaotong; Zhang Siqun; Chen Guanghua; Chang Lihua; Li Fengping; Ouyang Kai; Li Jun; Yang Liang; Wang Xiong; Zhang Zhaohui

    2006-01-01

    A preliminary experiment for studying the argon-puff Z-pinch implosion process has been performed on the Yang accelerator. The ten-frame nanosecond temporal and spatial gated camera, visible high-speed scanning camera, differential laser interferometer, X-ray time integration pinhole camera and X-ray power system have been used to investigated the evolution of the argon-puff Z-pinch. Some typical results of argon-puff Z-pinch during implosion and pinch phase, including the 'zipper' effect, necking phenomenon, sausage instability, temperature changes and the effect of load current rise time, are given and analyzed as examples, and some relevant conclusions are drawn. (authors)

  1. X-Pinch And Its Applications In X-ray Radiograph

    International Nuclear Information System (INIS)

    Zou Xiaobing; Wang Xinxin; Liu Rui; Zhao Tong; Zeng Naigong; Zhao Yongchao; Du Yanqiang

    2009-01-01

    An X-pinch device and the related diagnostics of x-ray emission from X-pinch were briefly described. The time-resolved x-ray measurements with photoconducting diodes show that the x-ray pulse usually consists of two subnanosecond peaks with a time interval of about 0.5 ns. Being consistent with these two peaks of the x-ray pulse, two point x-ray sources of size ranging from 100 μm to 5 μm and depending on cut-off x-ray photon energy were usually observed on the pinhole pictures. The x-pinch was used as x-ray source for backlighting of the electrical explosion of single wire and the evolution of X-pinch, and for phase-contrast imaging of soft biological objects such as a small shrimp and a mosquito.

  2. Dynamical analysis of surface-insulated planar wire array Z-pinches

    Science.gov (United States)

    Li, Yang; Sheng, Liang; Hei, Dongwei; Li, Xingwen; Zhang, Jinhai; Li, Mo; Qiu, Aici

    2018-05-01

    The ablation and implosion dynamics of planar wire array Z-pinches with and without surface insulation are compared and discussed in this paper. This paper first presents a phenomenological model named the ablation and cascade snowplow implosion (ACSI) model, which accounts for the ablation and implosion phases of a planar wire array Z-pinch in a single simulation. The comparison between experimental data and simulation results shows that the ACSI model could give a fairly good description about the dynamical characteristics of planar wire array Z-pinches. Surface insulation introduces notable differences in the ablation phase of planar wire array Z-pinches. The ablation phase is divided into two stages: insulation layer ablation and tungsten wire ablation. The two-stage ablation process of insulated wires is simulated in the ACSI model by updating the formulas describing the ablation process.

  3. Analisis Korelasi Kanonik Hubungan Perilaku Pemimpin dan Motivasi Kerja Karyawan

    Directory of Open Access Journals (Sweden)

    I Gusti Ayu Made Srinadi

    2014-06-01

    Full Text Available Kualitas pemimpin merupakan penentu keberhasilan organisasi yang dipimpin. Hubungan antara pemimpin dengan karyawannya merupakan hubungan saling ketergantungan yang umumnya tidak seimbang. Dalam proses interaksi yang terjadi antara pemimpin dan karyawan, berlangsung proses saling memengaruhi. Penelitian ini bertujuan untuk mencari hubungan perilaku pemimpin terhadap motivasi kerja karyawan dengan menggunakan analisis korelasi kanonik. Pengujian dengan menggunakan analisis korelasi kanonik menunjukkan bahwa perilaku pemimpin dengan motivasi karyawan memiliki keeratan hubungan dengan nilai korelasi kanonik sebesar 0,9058533. Faktor perilaku pemimpin yang paling tinggi berkorelasi dengan motivasi kerja karyawan di McDonald’s Kuta Beach adalah faktor kemampuan mengarahkan dan menghadapi karyawan dengan nilai korelasi yaitu sebesar 0,7619707.

  4. Analisis Korelasi Kanonik Hubungan Perilaku Pemimpin dan Motivasi Kerja Karyawan

    Directory of Open Access Journals (Sweden)

    I Gusti Ayu Made Srinadi

    2015-04-01

    Full Text Available Kualitas pemimpin merupakan penentu keberhasilan organisasi yang dipimpin. Hubungan antara pemimpin dengan karyawannya merupakan hubungan saling ketergantungan yang umumnya tidak seimbang. Dalam proses interaksi yang terjadi antara pemimpin dan karyawan, berlangsung proses saling memengaruhi. Penelitian ini bertujuan untuk mencari hubungan perilaku pemimpin terhadap motivasi kerja karyawan dengan menggunakan analisis korelasi kanonik. Pengujian dengan menggunakan analisis korelasi kanonik menunjukkan bahwa perilaku pemimpin dengan motivasi karyawan memiliki keeratan hubungan dengan nilai korelasi kanonik sebesar 0,9058533. Faktor perilaku pemimpin yang paling tinggi berkorelasi dengan motivasi kerja karyawan di McDonald’s Kuta Beach adalah faktor kemampuan mengarahkan dan menghadapi karyawan dengan nilai korelasi yaitu sebesar 0,7619707.

  5. Analisis Aliran Daya Berbasis Injeksi Arus dalam Bentuk Vektor

    Directory of Open Access Journals (Sweden)

    Ahmad Wira Satriawan

    2017-11-01

    Full Text Available Tulisan ini memaparkan hasil penelitian yang telah dilakukan untuk membandingkan metode analisis aliran daya berbasis injeksi arus dalam bentuk vektor dengan format polar dan rektangular. Penelitian ini dilakukan untuk memperoleh metode analisa aliran daya dengan perhitungan yang lebih cepat dan akurat, serta iterasi yang lebih sedikit. Metode iterasi Newton Raphson diadopsi dalam penelitian ini dan bahasa pemrograman Python serta library komputasinya digunakan. Analisis terhadap karakteristik konvergensi dari kedua format dilakukan pada IEEE 14-bus Test System. Dari penelitian ini diperoleh hasil bahwa format rektangular lebih unggul dibandingkan format polar untuk kasus yang diteliti.

  6. 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

    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....... 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....... The results of this study indicate that shoulder load might influence blood flow to the forearm....

  7. The fabrication techniques of Z-pinch targets. Techniques of fabricating self-adapted Z-pinch wire-arrays

    International Nuclear Information System (INIS)

    Qiu Longhui; Wei Yun; Liu Debin; Sun Zuoke; Yuan Yuping

    2002-01-01

    In order to fabricate wire arrays for use in the Z-pinch physical experiments, the fabrication techniques are investigated as follow: Thickness of about 1-1.5 μm of gold is electroplated on the surface of ultra-fine tungsten wires. Fibers of deuterated-polystyrene (DPS) with diameters from 30 to 100 microns are made from molten DPS. And two kinds of planar wire-arrays and four types of annular wire-arrays are designed, which are able to adapt to the variation of the distance between the cathode and anode inside the target chamber. Furthermore, wire-arrays with diameters form 5-24 μm are fabricated with tungsten wires, respectively. The on-site test shows that the wire-arrays can self-adapt to the distance changes perfectly

  8. Comparative study of millennials' (age 20-34 years) grip and lateral pinch with the norms.

    Science.gov (United States)

    Fain, Elizabeth; Weatherford, Cara

    Cross-sectional research design. Clinical practice continues to use normative data for grip and pinch measurements that were established in 1985. There is no updated norms despite different hand usage patterns in today's society. Measuring and comparing grip and pinch strengths with normative data is a valid method to determine hand function. This research was implemented to compare the grip and pinch measurements obtained from healthy millennials to the established norms and to describe hand usage patterns for millennials. Grip and lateral pinch measurements were obtained from a sample of 237 healthy millennials (ages 20-34 years). Strength scores were statistically lower that older normative data in all millennial grip strengths, with the exception of the women in the age group of 30-34 years. Specifically, this statistically significant trend was observed in all male grip strengths, as well as in women in the age group of 20-24 years (bilateral grip) and 25-29 years (right grip). However, the lateral pinch data reflected was similar to the older norms with variances of 0.5-1 kg. Current data reflect statistically significant differences from the norms for all male grip measurements, as well as for women in the age group of 20-24 years (bilateral grip) and 25-29 years (right grip). No statistical significance was observed in the independent-sample t tests for the lateral pinch in men of all age groups. Statistical significance was noted for lateral pinch for female age groups for the left hand (20-24 years) and for bilateral lateral pinches (30-34 years). IV. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

  9. Generation of an intense ion beam by a pinched relativistic electron beam

    International Nuclear Information System (INIS)

    Gilad, P.; Zinamon, Z.

    1976-01-01

    The pinched electron beam of a pulsed electron accelerator is used to generate an intense beam of ions. A foil anode and vacuum drift tube are used. The space charge field of the pinched beam in the tube accelerates ions from the foil anode. Ion currents of 10 kA at a density of 5kA/cm 2 with pulse length of 50 ns are obtained using a 5 kJ, 450 kV, 3 Ω diode. (author)

  10. Reduction of thermal expansion in Z-pinches by electron beam assisted magnetic field generation

    International Nuclear Information System (INIS)

    Heikkinen, J.A.; Karttunen, S.J.

    1989-01-01

    Weak radial expansion of a Z-pinch plasma column during its strong initial ohmic heating phase is expected when the generation of a confining magnetic field is assisted by a correctly formed electron beam pulse. Appropriate one-dimensional magnetohydrodynamic equations are numerically solved, and the observed increase of plasma radius as a function of time for various discharge parameters is compared to a normal Z-pinch discharge initiation. (author)

  11. Gas-puff Z-pinch experiment on the LIMAY-I

    International Nuclear Information System (INIS)

    Takasugi, K.; Miyamoto, T.; Akiyama, H.; Shimomura, N.; Sato, M.; Tazima, T.

    1989-01-01

    A gas-puff z-pinch plasma has been produced on the pulsed power generator LIMAY-I at IPP Nagoya University. The stored energy of the generator is 13 kJ, and it generates 600 kV-70 ns-3 Ω power pulse. Ar or He gas is puffed from a hollow nozzle with 18 mm diameter, and a z-pinch plasma is produced by a discharge between 3 mm gap electrodes

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

    International Nuclear Information System (INIS)

    Loverich, J.; Shumlak, U.

    2006-01-01

    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

  13. Pinch-off syndrome: transection of implantable central venous access device

    OpenAIRE

    Sugimoto, Takuya; Nagata, Hiroshi; Hayashi, Ken; Kano, Nobuyasu

    2012-01-01

    As the population of people with cancer increases so does the number of patients who take chemotherapy. Majority of them are administered parentally continuously. Implantable central venous catheter device is a good choice for those patients; however, severe complication would occur concerning the devices. Pinch-off syndrome is one of the most severe complications. The authors report a severe case of pinch-off syndrome. The patient with the implantable central venous device could not take che...

  14. 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.

  15. Review of effects of dielectric coatings on electrical exploding wires and Z pinches

    Science.gov (United States)

    Wu, Jian; Li, Xingwen; Li, Mo; Li, Yang; Qiu, Aici

    2017-10-01

    As the most powerful x-ray source in the laboratories, the wire array Z pinches have been of great relevance to inertial confinement fusions, laboratory astrophysics, and other high-energy density applications. In order to produce x-ray with greater power and higher efficiency, the dynamics of wire array has been investigated extensively, and various methods have been proposed to improve the implosion quality of the wire array. This review focuses on the experimental and theoretical investigations regarding the effects of the dielectric coatings on electrical exploding wires and Z pinches. Since the early 2000, the electrical wire explosion related to the first stage of the wire array Z pinches has been studied extensively, and the results indicated that the dielectric coatings can significantly increase the joule energy deposition into a wire in the initial stage, and even the corona free explosion of tungsten wires can be achieved. Recently, there is an increasing interest in the dynamics of insulated wire array Z pinches. By applying dielectric coatings, the ablation process is suppressed, the x-ray start time is delayed, and the possibility of multi-peak radiation is decreased. This review is organized by the evolution dynamics of wire array Z pinches, and a broad introduction to relevant scientific concepts and various other applications are presented. According to the current research status, the challenges, opportunities and further developments of Z pinch loads using dielectric coatings are proposed to further promote the researches and their applications.

  16. Review of effects of dielectric coatings on electrical exploding wires and Z pinches

    International Nuclear Information System (INIS)

    Wu, Jian; Li, Mo; Li, Yang; Li, Xingwen; Qiu, Aici

    2017-01-01

    As the most powerful x-ray source in the laboratories, the wire array Z pinches have been of great relevance to inertial confinement fusions, laboratory astrophysics, and other high-energy density applications. In order to produce x-ray with greater power and higher efficiency, the dynamics of wire array has been investigated extensively, and various methods have been proposed to improve the implosion quality of the wire array. This review focuses on the experimental and theoretical investigations regarding the effects of the dielectric coatings on electrical exploding wires and Z pinches. Since the early 2000, the electrical wire explosion related to the first stage of the wire array Z pinches has been studied extensively, and the results indicated that the dielectric coatings can significantly increase the joule energy deposition into a wire in the initial stage, and even the corona free explosion of tungsten wires can be achieved. Recently, there is an increasing interest in the dynamics of insulated wire array Z pinches. By applying dielectric coatings, the ablation process is suppressed, the x-ray start time is delayed, and the possibility of multi-peak radiation is decreased. This review is organized by the evolution dynamics of wire array Z pinches, and a broad introduction to relevant scientific concepts and various other applications are presented. According to the current research status, the challenges, opportunities and further developments of Z pinch loads using dielectric coatings are proposed to further promote the researches and their applications. (topical review)

  17. 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.

  18. Spatially and temporally resolved EUV emissions from SATURN z-pinches

    International Nuclear Information System (INIS)

    Nash, T.J.; Breeze, S.; Mock, R.; Jobe, D.

    1995-01-01

    EUV emissions can be used to measure several z-pinch parameters. The authors have measured implosion velocity from Doppler splitting of lines and estimated electron temperature during run-in from the mean ionization state of line emissions. In an argon pinch they measure an electron temperature of 100 eV before stagnation. To date Doppler split lines have measured implosion velocities less than 40 cm/microsecond. They are presently attempting to measure magnetic field or load current from Zeeman splitting and it may be possible to measure electron density from a Stark-broadened line. Opacity and ion thermal broadening may also contribute to line width information. The spectrometer utilizes a variable line space grating to give a flat focal field. Spectral resolution with a 60 micron detector resolution is up to 3,000 and generally increases with wavelength. This is sufficient to detect several plasma line broadening mechanisms. The spectrometer may detect lines above 100 angstrom and below 1,400 angstrom. Spectral range across a microchannel plate stripline detector decreases with increasing wavelength setting. The authors may gate two striplines with 1 to 12 nsec gates at any time during the pinch discharge. Each stripline spatially images the pinch diameter perpendicular to the direction of dispersion. Spatial resolution in the pinch diameter is 1 mm. Spatial acquisition along the z axis is also 1 mm. Data are presented from argon, krypton, and aluminum z-pinch discharges on the SATURN accelerator

  19. PBFA Z: A 20-MA z-pinch driver for plasma radiation sources

    International Nuclear Information System (INIS)

    Spielman, R.B.; Breeze, S.F.; Deeney, C.

    1996-01-01

    Sandia National Laboratories is completing a major modification to the PBFA-II facility. PBFA Z will be a z-pinch driver capable of delivering up to 20 MA to a z-pinch load. It optimizes the electrical coupling to the implosion energy of z pinches at implosion velocities of ∼ 40 cm/μs. Design constraints resulted in an accelerator with a 0.12-Ω impedance, a 10.25-nH inductance, and a 120-ns pulse width. The design required new water transmission lines, insulator stack, and vacuum power feeds. Current is delivered to the z-pinch load through four, self-magnetically-insulated vacuum transmission lines and a double post-hole convolute. A variety of design codes are used to model the power flow. These predict a peak current of 20 MA to a z-pinch load having a 2-cm length, a 2-cm radius, and a 15--mg mass, coupling 1.5 MJ into kinetic energy. We present 2-D Rad-Hydro calculations showing MJ x-ray outputs from tungsten wire-array z pinches

  20. Plasma-erosion-enhanced neutron emission in fiber-generated dense Z-pinches

    International Nuclear Information System (INIS)

    Mosher, D.; Colombant, D.

    1990-01-01

    Experiments in which dense z-pinches are created from high-current discharges through frozen deuterium fibers have reported neutron yields far in excess of those expected from thermal processes. A simple analysis based on pinch collapse due to the sausage instability has successfully predicted the relative variation of neutron yield with discharge current, but model assumptions precluded prediction of absolute values of the yield. A pinch-collapse model derived from a 2-dimensional, nonlinear treatment of the sausage instability, combined with space-charged-limited (SCL) ion orbital dynamic for the vacuum region above the pinches and between the expanding flares, leads to neutron yields four or more orders-of-magnitude below experimental values. Here, the same pinch-collapse model is used in conjunction with a low-density plasma background above the collapsing pinches. Ions are accelerated across the space-charge sheath separating the background plasma from the flares, which electron emission from the flares is strongly insulated by the z-discharge magnetic field. The sheath gap increases in time, i.e., the background plasma erodes, at a rate determined by its density and the SCL ion current density which, in turn, depends on the z-discharge dynamics and the associated induced electromagnetic fields. A model incorporating the above processes is used to determine the accelerated ion energy spectrum and associated neutron yield as functions of the discharge, instability, and background parameters

  1. The pinch of cold ions from recycling in the tokamak edge pedestal

    International Nuclear Information System (INIS)

    Wan Weigang; Parker, Scott E.; Chen Yang; Park, Gun-Young; Chang, Choong-Seock; Stotler, Daren

    2011-01-01

    We apply the ''natural fueling mechanism'' [W. Wan, S. E. Parker, Y. Chen, and F. W. Perkins, Phys. Plasmas 17, 040701 (2010)] to the edge pedestal. The natural fueling mechanism is where cold ions naturally pinch radially inward for a heat-flux dominated plasma. It is shown from neoclassical-neutral transport coupled simulations that the recycling neutrals and the associated source ions are colder than the main ions in the edge pedestal. These recycling source ions will pinch radially inward due to microturbulence. Gyrokinetic turbulence simulations indicate that near the top of the pedestal, the pinch velocity of the recycling source ions is much higher than the main ion outgoing flow velocity. The turbulent pinch of the recycling source ions may play a role in the edge pedestal transport and dynamics. The cold ion temperature significantly enhances the pinch velocity of the recycling source ions near to the pedestal top. Neoclassical calculations show a cold ion pinch in the pedestal as well.

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

    International Nuclear Information System (INIS)

    Soto, L.; Chuaqui, H.; Favre, M.; Saavedra, R.; Wyndham, E.; Aliaga-Rossel, R.; Mitchell, I.

    1996-01-01

    Recent experiments in a gas embedded compressional Z-pinch are presented. The experiments have been carried out in H 2 at 1/3 atm, using a pulse power generator capable of delivering a dl/dt > 10 12 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

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

    International Nuclear Information System (INIS)

    Shumlak, U.; Crawford, E.; Golingo, R.P.; Nelson, B.A.; Zyrmpas, A.; Den Hartog, D.J.; Holly, D.J.

    2001-01-01

    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 9.6x10 4 m/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)

  4. ANALISIS FAKTOR KEHADIRAN DOSEN DI UNIVERSITAS X

    Directory of Open Access Journals (Sweden)

    Annisa Mulia Rani

    2016-10-01

    Full Text Available Aspek kualitas pekerjaan berkaitan langsung dengan waktu yang khusus digunakan dosen untuk mengembangkan kemampuan. Maka untuk merealisasikan kualitas dosen yang terbaik , pihak manajemen khusunya dekan membuat peraturan untuk kehadiran dosen adalah minimal 25 jam/minggu. Dengan peraturan ini diharapkan dosen dapat melaksanakan beban kerja dosen sebaik-baiknya. Peraturan ini tertulis dan tertuang pada SK Dekan No 20/2006 pada kampus X. Dengan Menggunakan Analisis faktor mencoba menemukan hubungan atar sejumlah variable-variabel yang awalnya saling independen satu dengan yang lain dimana variable penyebab kekurangan jam dosen datang/minggu adalah keluaraga, manajemen, hubungan social, fasilitas pengajaran, jarak/lokasi, kompensasi transport. Berdasarkan uji Bartley test dan Measure sample of adequate yang pertama maka dengan nilai sig 0.04 dan msa 0.540 . Dengan menggunakan metode principal component analysis maka pembentukan factor hanya ada 1 componen karena nilai eigen value yang mempunyai nilai diatas 1. Faktor pembentuk baru yaitu manajemen, kompensasi dan jarak menjadi satu component.

  5. 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.

  6. Correlacion entre metodos de analisis de Zn disponible en cuatro ordenes de suelos de Costa Rica

    Directory of Open Access Journals (Sweden)

    Eloy Molina

    2001-01-01

    Full Text Available Se realizo una comparación entre métodos analisis del Zn disponible en 4 ordenes de sue- Analytilos de Costa Rica (Ultisoles, Vertisoles, Andisoles Inceptisoles, 25 de c/u, utilizando las siguientes soluciones extractoras: Olsen Modificado, Meh- lich 3, Morgan Modificado, DTPA y HC1. Las cantidades de Zn extrafdas dependieron de la natu- raleza qufmica de la solucion extractora. El HCl presento los contenidos mas altos de Zn en los chasuelos, excepto en Vertisoles. Las soluciones que hicontienen el agente quelante EDTA (Olsen Modi- ficado y Mehlich`3, extrajeron niveles interme- Modidios de Zn, en tanto que los metodos que contie- Den el quelato DTPA (Morgan Modificado y DT - PA, obtuvieron los valores mas bajos. Las corre- laciones de Zn extrafble entre los 5 metodos fue- signifirOD significativas en la mayona de los casos, tanto nivel de orden de suelos como en el conjunto de indivilos 100 suelos analizados. Los coeficientes de co- rrelacion mas altos, se presentaron entre Mehlich Morgan Modificado y DTPA. Las correlaciones Modifueron consistentes en los 4 ordenes, 10 que indica que estas soluciones poseen un amplio margen de adaptacion a diferentes tipos de suelo, siendo una caractenstica ventajosa para la selección de un metodo de analisis. El Olsen Modificado fue mas slighteficiente para la extraccion de Zn en suelos de pH ligeramente acido 0 neutro (Vertisoles e Inceptiso- les, que en suelos acidos (Ultisoles y Andisoles. EI HCI extrajo cantidades muy aItas de Zn que Moraparentementestan relacionadas con formas no disponibles para lag plantas. Se concluye que lag soluciones Mehlich 3, Morgan Modificado y DT - PA son semejantes en la forma de extraer Zn dispo- Dible, y podrian seT una altemativa para sustituir el metoda tradicional de Olsen Modificado utilizado en Costa Rica. Sin embargo,la eficiencia de ellas no puede seT establecida sino a traves de log estudios de correlacion contra rendimiento en invernadero y campo.

  7. Study of the internal structure, instabilities, and magnetic fields in the dense Z-pinch

    International Nuclear Information System (INIS)

    Ivanov, Vladimir V.

    2016-01-01

    Z-pinches are sources of hot dense plasma which generates powerful x-ray bursts and can been applied to various areas of high-energy-density physics (HEDP). The 26-MA Z machine is at the forefront of many of these applications, but important aspects of HEDP have been studied on generators at the 1 MA current level. Recent development of laser diagnostics and upgrade of the Leopard laser at Nevada Terawatt Facility (NTF) give new opportunities for the dense Z-pinch study. The goal of this project is the investigation of the internal structure of the stagnated Z pinch including sub-mm and micron-scale instabilities, plasma dynamics, magnetic fields, and hot spots formation and initiation. New plasma diagnostics will be developed for this project. A 3D structure and instabilities of the pinch will be compared with 3D MHD and spectroscopic modeling and theoretical analysis. The structure and dynamics of stagnated Z pinches has been studied with x-ray self-radiation diagnostics which derive a temperature map of the pinch with a spatial resolution of 70-150 µm. The regular laser diagnostics at 532 nm does not penetrate in the dense pinch due to strong absorption and refraction in trailing plasma. Recent experiments at NTF showed that shadowgraphy at the UV wavelength of 266 nm unfolds a fine structure of the stagnated Z-pinch with unprecedented detail. We propose to develop laser UV diagnostics for Z pinches with a spatial resolution 20 MG, suggested in micropinches, Cotton-Mouton and cutoff diagnostics will be applied. A picosecond optical Kerr shutter will be tested to increase a sensitivity of UV methods for application at multi-MA Z pinches. The proposal is based on the experimental capability of NTF. The Zebra generator produces 1-1.7 MA Z-pinches with electron plasma density of 10"2"0-10"2"1cm"-"3, electron temperature of 0.5-1 keV, and magnetic fields >10 MG. The Leopard laser was upgraded to energy of 90-J at 0.8 ns. This regime will be used for laser initiation

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

    International Nuclear Information System (INIS)

    Cuneo, Michael E.; Vesey, Roger A.; Porter, John L. Jr.; Chandler, Gordon A.; Fehl, David L.; Gilliland, Terrance L.; Hanson, David L.; McGurn, John S.; Reynolds, Paul G.; Ruggles, Laurence E.; Seamen, Hans; Spielman, Rick B.; Struve, Ken W.; Stygar, William A.; Simpson, Walter W.; Torres, Jose A.; Wenger, David F.; Hammer, James H.; Rambo, Peter W.; Peterson, Darrell L.

    2001-01-01

    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)

  9. Efektivitas dan Kendala Pembelajaran Sains Berbasis Inkuiri terhadap Capaian Dimensi Kognitif Siswa: Meta Analisis

    Directory of Open Access Journals (Sweden)

    Abdurrahman Abdurrahman

    2017-06-01

    teknologi informasi. Pembelajaran berbasis inkuiri sering disusun dalam fase penyelidikan yang berfokus untuk membangun kemampuan sains bagi para siswa. Namun, variasi yang berbeda mengenai makna kompetensi penyelidikan sering kita temukan di berbagai literatur. Artikel ini berfokus untuk mengidentifikasi dan meringkas fitur inti dari pembelajaran berbasis inkuiri melalui metode meta analisis, mengkaji literatur secara sistematis dan mengembangkan proses penyelidikan yang disintesis dengan menggabungkan kekuatan kerangka kerja pembelajaran berbasis inkuiri yang ada untuk meningkatkan prestasi belajar siswa. Kajian ini dilakukan dengan menggunakan basis data dari Web of Science dan ERIC (Education Resources Information Center; Sebanyak 15 artikel yang menjelaskan tahap penyelidikan atau keseluruhan proses penyelidikan dipilih berdasarkan kriteria pencarian yang spesifik. Analisis terhadap artikel menghasilkan identifikasi lima fase penyelidikan umum yang dapat berbeda secara istilah satu sama lainnya yaitu: Orientasi, Konseptualisasi, Investigasi, Diskusi dan Kesimpulan. Disamping itu, hampir seluruh pembelajaran berbasis inkuiri biasanya berakhir dengan fase Kesimpulan. Berdasarkan analisis di seluruh hasil penelitian menunjukkan bahwa pembelajaran berbasis inkuiri telah berhasil menunjukkan peningkatan penguasaan aspek kognitif siswa secara signifikan.

  10. BAHASA DAN IDEOLOGI: MENGUNGKAP IDEOLOGI DAN KEKUASAAN SIMBOLIK DI BALIK PENGGUNAAN BAHASA (KAJIAN TEKS MEDIA MELALUI ANALISIS WACANA KRITIS

    Directory of Open Access Journals (Sweden)

    Su haryo

    2014-11-01

    Full Text Available Abstrak   Tulisan ini didasari sebuah anggapan bahwa bahasa tidak berada di ruang hampa sosial.Maka, bahasa pada dasarnya bukan hanya untaian kata yang hanya bersifat linguistik, tetapi bersifat sosial. Karenanya, bahasa dipahami sebagai tindakan sosial.Implikasinya, bahasa bukan hanya bermatra linguistik, tetapi juga bermatra sosial. Van Dijk menjadi salah satu model yang dapat digunakan sebagai alat untuk menganalisis wacana secara kritis. Penelitian analisis wacana kritis model van Dijk mempertimbangkan teks, konteks, kognisi sosial, dan analisis/konteks sosial. Untuk mengungkap hal itu, langkah yang dapat dilakukan adalah: mengungkap struktur makro (tematik, suprstruktur (skematik, dan struktur mikro yang terdiri atas semantik, sintaksis, stilitistik, dan retorika. Untuk mengungkap hal itu, di sini digunakan metode simak dan catat dengan menjadikan Suara Merdeka dan Kompassebagai sumber datanya. Hasilnya pertama,SM cenderung berideologi kasar, provokatif, dan konotatif/figuratif. Hal itu, tampak pada pilihan kata/kalimat  kata yang cenderung kasar, seperti mengancam,menyerang, memanggil paksa, menyeret, menembak.Sementara, harian K cenderung berideologi idealisme pers yang objektif, netral, dan berimbang. Kedua, dari dimensi kekuasaan (simbolik, harian SM cenderung menjadi “oposisi”  dan “oposan”sebagai pihak yang di-dominan-kan, sedang pihak pemerintah sebagai pihak yang “dimarginalkan”. Sementara, harian K menempatkan pihak yang dominan/marginal lebih didasarkan pada kondisi objektif di lapangan yang  berbasis data dan keterangan yang dari narasumber yang cenderung netral, seperti pengamat, warga, dan akademisi; tidak didasarkan pada keterangan yang cenderung subjektif, seperti dari para politisi.Ketiga, dari sisi analisis sosial dan kognisi sosial; SM lebih tampak sebagai cerminan tagline-nya yaitu lokal (yaitu “perekat komunitas Jawa Tengah”, sedangkan harian K lebih “mengabdi” pada rakyat seperti tampak pada

  11. ANALISIS KONTRIBUSI PAJAK HOTEL TERHADAP PENDAPATAN ASLI DAERAH KABUPATEN NUNUKAN

    OpenAIRE

    -, MULIATI

    2014-01-01

    2014 Analisis Kontribusi Pajak Hotel terhadap Pendapatan Asli Daerah Kabupaten Nunukan Analysis of The Contributions Tax on Hotel Againts Regional Renenue Nunukan District Muliati Haerial M. Christian Mangiwa Penelitian ini bertujuan untuk mengetahui seberapa besar kontribusi pajak hotel terhadap pendapatan asli daerah, mengetahui sistem pengawasan, dan potensi yang ada untuk meningkatkan pajak hotel, mengetahui sistem dan prosedur...

  12. Analisis Sektor/Sub Sektor Unggulan di Kabupaten Bungo

    Directory of Open Access Journals (Sweden)

    Gafur Gafur

    2016-03-01

    Full Text Available Abstract. This study aimed to analyze the leading sectors in Bungo. The method used is Location Quotient (LQ, Dynamic Location Quotient (DLQ, specialization index, Growth Ratio Model (MRP. Based on analysis of LQ and DLQ, there are only two basis sectors at present and in the future, namely the construction sector and trade, hotels and restaurants. Based on the analysis of Specialization Index, in Bungo Regency has a concentration of the economy in the agricultural sector and the manufacturing sector. Based on MRP analysis also showed that prominent sector growth at the level of Bungo and Jambi Province, namely electricity, gas and water supply; the building sector; and trade, hotels and restaurants. Keywords : Location Quotient (LQ, Dinamic Location Quotient (DLQ, Specialization Index, Growth Ratio Model   Abstrak. Penelitian ini bertujuan untuk menganalisis sektor unggulan di Kabupaten Bungo. Metode yang digunakan adalah analisis Location Quotient (LQ, Dinamic Location Quotient (DLQ, indeks spesialisasi, Model Rasio Pertumbuhan (MRP. Berdasarkan analisis LQ dan DLQ,  hanya ada 2 sektor yang menjadi sektor basis pada saat ini dan pada masa yang akan datang yaitu sektor bangunan dan sektor perdagangan, hotel dan restoran. Berdasarkan analisis Indeks Spesialisasi, di Kabupaten Bungo telah terjadi konsentrasi ekonomi pada sektor pertanian dan sektor industri pengolahan. Berdasarkan analisis MRP juga dapat diketahui bahwa sektor yang menonjol pertumbuhannya pada tingkat Kabupaten Bungo dan Provinsi Jambi yaitu sektor listrik, gas dan air bersih; sektor bangunan; serta sektor perdagangan, hotel dan restoran. Kata Kunci : Location Quotient (LQ, Dinamic Location Quotient (DLQ, indeks spesialisasi, Model Rasio Pertumbuhan

  13. Experiments on a Toroidal Screw Pinch with Various Field Programming

    Energy Technology Data Exchange (ETDEWEB)

    Zwicker, H.; Wilhelm, R.; Krause, H. [Max-Planck-Institut Fuer Plasmaphysik, EURATOM-Association, Garching, Munich, Federal Republic of Germany (Germany)

    1971-10-15

    In the toroidal screw pinch ISAR-IV (large diameter 60 cm, aspect ratio 5, maximum storage, energy 140 kj) attempts were made to get an improved stability of the plasma by different kinds of field programming. The best results were obtained with positive trapped B{sub z}-fields and simultaneous switching of main B{sub z}-field and I{sub z}-current. In this case the dense plasma column (n{sub e} Almost-Equal-To 2-3 x 10{sup 16} , kT Almost-Equal-To 50-100 eV, {beta} Almost-Equal-To 15-20%) is surrounded by a force-free plasma ({beta} = 1%) with weak shear and it behaves stably for, at least, 25 {mu}s. The resulting containment time nr of near 10{sup 12} s cm{sup -3} remains a factor of 2-3 below the upper limit given by the classical diffusion. The following loss of the equilibrium position near the coil axis ({Delta} Almost-Equal-To 1-2 cm) is connected to a strong damping of the axial plasma current which starts near the end of the containment. It may be assumed that the increase of the effective plasma resistance mainly results from a contact of the force-free regions with the tube wall. Attempts were made to improve the containment by suitable programming of a plasma z-current. The results are presented. Experiments with one quartz limiter inside the torus improved the equilibrium but introduced instabilities at the new surface of the dilute plasma. To obtain more information about the outer region, the dilute plasma was produced without a dense core and separated from the tube walls by weak adiabatic compression. Under these Tokamak-like conditions the q-value was varied. In the region of q Almost-Equal-To 1 there appeared instabilities which seem to haver higher m-modes and rather short wavelengths. In a different kind of field programming the field distribution of the ''diffuse pinch'' was realized within an accuracy of 5-10% (kT Almost-Equal-To 100 eV, {beta} Almost-Equal-To 30%). In contrast to the predictions of MHD-theory, stability was observed only for

  14. Plasma dynamics in aluminium wire array Z-pinch implosions

    International Nuclear Information System (INIS)

    Bland, S.N.

    2001-01-01

    The wire array Z-pinch is the world's most powerful laboratory X-ray source. An achieved power of ∼280TW has generated great interest in the use of these devices as a source of hohlraum heating for inertial confinement fusion experiments. However, the physics underlying how wire array Z-pinches implode is not well understood. This thesis presents the first detailed measurements of plasma dynamics in wire array experiments. The MAGPIE generator, with currents of up to 1.4MA, 150ns 10-90% rise-time, was used to implode arrays of 16mm diameter typically containing between 8 and 64 15μm aluminium wires. Diagnostics included: end and side-on laser probing with interferometry, schlieren and shadowgraphy channels; radial and axial streak photography; gated X-ray imaging; XUV and hard X-ray spectrometry; filtered XRDs and diamond PCDs; and a novel X-ray backlighting system to probe high density plasma. It was found that the plasma formed from the wires consisted of cold, dense cores, which ablated producing hot, low density coronal plasma. After an initial acceleration around the cores, coronal plasma streams flowed force-free towards the axis, with an instability wavelength determined by the core size. At ∼50% of the implosion time, the streams collided on axis forming a precursor plasma which appeared to be uniform, stable, and inertially confined. The existence of core-corona structure significantly affected implosion dynamics. For arrays with <64 wires, the wire cores remained in their original positions until ∼80% of the implosion time before accelerating rapidly. At 64 wires a transition in implosion trajectories to 0-D like occurred indicating a possible merger of current carrying plasma close to the cores - the cores themselves did not merge. During implosion, the cores initially developed uncorrelated instabilities that then transformed into a longer wavelength global mode of instability. The study of nested arrays (2 concentric arrays, one inside the other

  15. 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

  16. 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

  17. Experimental studies of Z-pinches of mixed wire array with aluminum and tungsten

    International Nuclear Information System (INIS)

    Ning Cheng; Li Zhenghong; Hua Xinsheng; Xu Rongkun; Peng Xianjue; Xu Zeping; Yang Jianlun; Guo Cun; Jiang Shilun; Feng Shuping; Yang Libing; Yan Chengli; Song Fengjun; Smirnov, V.P.; Kalinin, Yu.G.; Kingsep, A.S.; Chernenko, A.S.; Grabovsky, E.V.

    2004-01-01

    In the form of joint experiment between China and Russia, the experimental studies of Z-pinches of mixed wire array of aluminum (A1) and tungsten (W) were carried out on S-300 generator, which was located on Kurchatov Institute of Russia. The experimental results were compared with those of single A1 array and single W array, respectively. There are obvious difference between mixed one and single one in their photon spectral distributions. The intensity of K-series emission lines from the mixed wire array Z-pinch is lower than that from single A1 array. The radiated lines with wavelengths less than 1.6 nm were not found in single W array Z-pinches. In the Z-pinch processes, the area radiating x-rays in mixed wire array is smaller than that of single A1 array, but is slightly lower than that from single W array. The FWHM of x-ray pulse with a maximal power 0.3-0.5 TW and total energy 10-20 kJ is about 25 ns, which radiated from Z-pinches with a radial convergence of 4-5 on S-300 generator. The shadow photograph of the mixed wire-array Z-pinch plasma by laser probe shows that the core-corona configuration was formed and the corona was moving toward the center axis during the wire-array plasma formation, that the interface of the plasma is not clear, and that there are a number structures inside. They also suggests that there was an obvious development of Magneto Rayleigh-Taylor instability in the Z-pinch process as well

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

    Science.gov (United States)

    Sethian, John

    1997-05-01

    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.

  19. Pellet injection in the RFP (Reversed Field Pinch)

    Science.gov (United States)

    Wurden, G. A.; Weber, P. G.; Munson, C. P.; Cayton, T. E.; Bunting, C. A.; Carolan, P. G.

    Observation of pellets injected into the ZT-40M Reversed Field Pinch has allowed a new twist on the usual tokamak ablation physics modeling. The RFP provides a strong ohmic heating regime with relatively high electron drift parameter (xi sub drift approx. 0.2), in the presence of a highly sheared magnetic field geometry. In situ photos of the pellet ablation cloud using a grated-intensified CCD camera, as well as two-view integrated photos of the pellet trajectory show substantial modification of the original pellet trajectory, in both direction and speed. Depending on the launch geometry, increases in the initial 500 m/s pellet speed by 50 percent were observed, and a ski jump deflector plate in the launch port has been used to counteract strong poloidal curvature. In contrast to the tokamak, the D sub alpha light signature is strongest near the edge, and weaker in the plasma center. Additional information on ion temperature response to pellet injection with 20 microsec time resolution has been obtained using a 5-channel neutral particle analyzer (NPA). The energy confinement is transiently degraded while the beta is largely unchanged. This may be indicative of pellet injection into a high-beta plasma operating at fixed beta.

  20. Measurement of the ion temperature in a diffuse theta pinch

    International Nuclear Information System (INIS)

    Kudo, Koichi; Watanabe, Yukio; Ogi, Sukeomi; Sumikawa, Toshio; Akazaki, Masanori

    1979-01-01

    The Doppler broadening of helium ion spectra was observed, and the ion temperature of theta pinch plasma was obtained. The apparatus for the measurement consists of a spectroscope, a photomultiplier and an oscilloscope. The time variation of initial plasma density was obtained. The doppler broadening of the spectra was observed in case of the plasma density of 2 x 10 13 /cm 3 and 3 x 10 12 /cm 3 . The analyses of the spectra gave the ion temperature. The double temperature distribution was seen. The temperature of the low temperature part was 5 to 9 electron-volt, and that of the high temperature part several hundred electron-volt. The high temperature is caused by the thermalization of particles accelerated by the magnetic piston. The decay of high temperature ions is due to the charge exchange with the neutral particles. The time of the highest temperature corresponds to the time at which the luminescent layer reaches to the central axis. (Kato, T.)

  1. Scaling of sustained ZT-40 M reversed field pinches

    International Nuclear Information System (INIS)

    Graham, J.; Haberstich, A.; Baker, D.A.; Buchenauer, C.J.; Caramana, E.J.; DiMarco, J.N.; Erickson, R.M.; Ingraham, J.C.; Jacobson, A.R.; Little, E.M.; Massey, R.S.; Phillips, J.A.; Schoenberg, K.F.; Schofield, A.E.; Thomas, K.S.; Watt, R.G.; Weber, P.G.

    1993-12-01

    Experiments aimed at evaluating the scaling properties of the ZT-40M Reversed-Field Pinch (RFP) facility were conducted in 1983 at Los Alamos. Sustained discharges were produced at nominal toroidal currents ranging from 60 to 240 kA. The standard fill pressure was kept close to the lower limit of the usable pressure range, and the scaling data were acquired at a fixed time in the discharges while the plasma was in a quasi-steady state. Scalings of the diameter-averaged electron density, electron temperature on axis, product of these two parameters, and of various definitions of the electrical resistivity are presented. Trends of the toroidal voltage, energy containment time, and poloidal beta are shown. The impurity contents, particle containment time, and total radiation losses are described, and results obtained with and without poloidal limiters are compared. In addition, the performance of the facility at higher than standard density and at a constant ratio of the toroidal current over the electron line density is examined

  2. Nonlinear dynamics of tearing modes in the reversed field pinch

    International Nuclear Information System (INIS)

    Holmes, J.A.; Carreras, B.A.; Diamond, P.H.; Lynch, V.E.

    1987-05-01

    The results of investigations of nonlinear tearing-mode dynamics in reversed field pinch plasmas are described. The linear instabilities have poloidal mode number m = 1 and toroidal mode numbers 10 ≤ n ≤ 20, and the resonant surfaces are therefore in the plasma core. The nonlinear dynamics result in dual cascade processes. The first process is a rapid m = 1 spectral broadening toward high n, with a simultaneous spreading of magnetic turbulence radially outward toward the field-reversal surface. Global m = 0 perturbations, which are driven to large amplitudes by the m = 1 instabilities, in turn trigger the m = 1 spectral broadening by back-coupling to the higher n. The second process is a cascade toward large m and is mediated by m = 2 modes. The m = 2 perturbations have the structure of localized, driven current sheets and nonlinearly stabilize the m = 1 modes by transferring m = 1 energy to small-scale dissipation. The calculated spectrum has many of the qualitative features observed in experiments. 13 refs., 21 figs., 1 tab

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

    International Nuclear Information System (INIS)

    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

  4. Confined discharge plasma sources for Z-pinch experiments

    International Nuclear Information System (INIS)

    Hinshelwood, D.D.; Goodrich, P.J.; Mehlman, G.; Scherrer, V.E.; Stephanakis, S.J.; Young, F.C.

    1989-01-01

    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 (MgF 2 ), and aluminum (Al 2 0 3 ). 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

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

    International Nuclear Information System (INIS)

    Sarff, J.S.; Almagri, A.F.; Anderson, J.K.; Borchardt, M.; Carmody, D.; Caspary, K.; Chapman, B.E.; Den Hartog, D.J.; Duff, J.; Eilerman, S.; Falkowski, A.; Forest, C.B.; Goetz, J.A.; Holly, D.J.; Kim, J.-H.; King, J.; Ko, J.; Koliner, J.; Kumar, S.; Lee, J.D.

    2013-01-01

    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)

  6. Plasma behaviour in large reversed-field pinches and reactors

    International Nuclear Information System (INIS)

    Christiansen, J.P.; Bodin, H.A.B.; Carolan, P.G.; Johnston, J.W.; Newton, A.A.; Roberts, K.V.; Robinson, D.C.; Watts, M.R.C.; Piotrowicz, V.A.

    1981-01-01

    Recent analytic and numerical results on large reversed-field-pinch (RFP) systems and RFP reactors are presented. Predictions are made of the plasma behaviour in Eta Beta II, HBTXIA (under construction) and RFX (planned). The setting-up phase of an RFP is studied by using turbulence theory in transport equilibrium calculations, and estimates are made of the volt-seconds consumption for four different modes of field control. A prescription is given for a dynamo producing self-reversal which yields finite-β configurations. Residual instabilities of these equilibria may be resistive pressure-driven g-modes, and a new study of these modes that includes parallel viscosity indicates stability for anti β approximately 10%. The sustainment phase of the RFP is examined with tokamak scaling laws assumed for the energy confinement time. Temperatures in excess of 1keV are predicted for currents of 2MA in RFX. An operating cycle for a pulsed RFP reactor including gas puffing to reach ignition is proposed following a study of the energy replacement time for an Ohmically heated plasma. The scaling of the reactor parameters with minor radius is also investigated. (author)

  7. Paramagnetism and plasma beta in a screw-pinch

    International Nuclear Information System (INIS)

    Lehnert, B.; Scheffel, J.

    1991-02-01

    Anisotropic resistivity causes paramagnetic effects (B z ' (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)

  8. If it’s pinched it’s a memristor

    International Nuclear Information System (INIS)

    Chua, Leon

    2014-01-01

    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. (tutorial)

  9. Pinched flow fractionation of microbubbles for ultrasound contrast agent enrichment

    Science.gov (United States)

    Versluis, Michel; Kok, Maarten; Segers, Tim

    2014-11-01

    An ultrasound contrast agent (UCA) suspension contains a wide size distribution of encapsulated microbubbles (typically 1-10 μm in diameter) that resonate to the driving ultrasound field by the intrinsic relationship between bubble size and ultrasound frequency. Medical transducers, however, operate in a narrow frequency range, which severely limits the number of bubbles that contribute to the echo signal. Thus, the sensitivity can be improved by narrowing down the size distribution of the bubble suspension. Here, we present a novel, low-cost, lab-on-a-chip method for the sorting of contrast microbubbles by size, based on a microfluidic separation technique known as pinched flow fractionation (PFF). We show by experimental and numerical investigation that the inclusion of particle rotation is essential for an accurate physical description of the sorting behavior of the larger bubbles. Successful sorting of a bubble suspension with a narrow size distribution (3.0 +/- 0.6 μm) has been achieved with a PFF microdevice. This sorting technique can be easily parallelized, and may lead to a significant improvement in the sensitivity of contrast-enhanced medical ultrasound. This work is supported by NanoNextNL, a micro and nanotechnology consortium of the Government of the Netherlands and 130 partners.

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

    International Nuclear Information System (INIS)

    Watts, C.; Newman, D.E.; Sprott, J.C.

    1994-01-01

    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

  11. Filamentation instability of a self-pinched hollow electron beam

    International Nuclear Information System (INIS)

    Uhm, H.S.; Hughes, T.P.

    1986-01-01

    Filamentation stability properties of a self-pinched hollow electron beam propagating through a collisional plasma channel are investigated within the framework of linearized Vlasov--Maxwell equations, assuming that the beam is thin and that the equilibrium and perturbed space-charge fields are neutralized by background plasma. It is further assumed that the perturbations are well tuned with kβ/sub b/c+lω/sub b/ and satisfy la 0 , where l and k are the azimuthal and axial wavenumbers, β/sub b/c and ω/sub b/ are the axial velocity and the rotational frequency of the beam, and 2a and R 0 are the thickness and mean radius of the beam. From the stability analysis, two distinctive unstable mechanisms are identified: the return-current driven instability and the resistively driven instability. It is also found that high-l-mode perturbations are easily stabilized by a spread in the canonical angular momentum. Making use of a linearized particle-in-cell code, numerical simulations are performed. The agreement between the analytical results and those of simulations is excellent

  12. Confinement properties of the RFP [Reversed Field Pinch

    International Nuclear Information System (INIS)

    Weber, P.G.; Schoenberg, K.F.; Ingraham, J.C.; Miller, G.; Munson, C.P.; Pickrell, M.M.; Wurden; Tsui, H.Y.W.; Ritz, Ch.P.

    1990-01-01

    Research in ZT-40M has been focused on elucidating the confinement properties of the Reversed Field Pinch (RFP). Recent improvements in diagnostic capability have permitted measurement of radial profiles, as well as a detailed study of the edge plasma. The emerging confinement picture for ZT-40M has several ingredients: Typically 0.3 of the Ohmic input power to ZT-40M is available to drive fluctuations. Evidence points to this fluctuational power heating the ions. Approximately one quarter of the input power is lost through radiation, with metal impurities playing a key role. Magnetic fluctations in ZT-40M are at the percent level, as measured in the edge plasma. Extrapolating these data to small radii shows stochasticity in the core plasma. Suprathermal electrons are measured in the edge plasma. These electrons originate in the core, and transport to the edge along the fluctuating magnetic field lines. Under typical conditions, these electrons constitute the major electron energy loss channel in ZT-40M. Electrostatic fluctuations dominate the edge electron particle flux, but not the electron thermal flux. The major ion loss process is charge exchange, with smaller contributions from conduction and convection. In examining these observations, and the parametric dependences of confinement, a working model for RFP confinement emerges. An overview of this model, together with implications for the multi-mega-ampere ZTH experiment will be presented

  13. The dense Z-pinch project at Imperial College

    International Nuclear Information System (INIS)

    Haines, M.G.; Dangor, A.E.; Choi, P.; Mitchell, I.; Coppins, M.; Chittenden, J.P.; Culverwell, I.D.; Bayley, J.; Power, A.

    1990-01-01

    The Science and Engineering Research Council has recently awarded a grant of over L0.8M to build a large new Z-pinch driven by a high voltage pulsed power generator. The generator will be 4 Marx generators in parallel which together will supply up to 2MA at 2.85MV for 200ns. When the load is a frozen fibre of hydrogen, it is predicted that radiative collapse above the Pease-Bragniskii current will lead to ultra high density (10 4 x solid density) at 10 to 20 KeV temperature. Deuterium-tritium fibres would lead to conditions close to thermonuclear breakeven. Scaled experiments at lower currents reveal anomalous stability due to finite Larmor radius effects in one case or to a low magnetic Lundquist number in another. The theory of stability has been extensively studied in many regimes, and it is found the ideal MHD occupies a small fraction of parameter space. (author) 7 refs., 3 figs

  14. The physics of the high density Z-pinch

    International Nuclear Information System (INIS)

    Glasser, A.H.; Hammel, J.E.; Lewis, H.R.

    1988-01-01

    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

  15. Simulation study of dynamo structure in reversed field pinch

    International Nuclear Information System (INIS)

    Nagata, A.; Sato, K.I.; Ashida, H.; Amano, T.

    1992-10-01

    The dynamo structure in the reversed field pinch (RFP) is studied through the nonlinear dynamics of single-helicity mode. Simulation is concentrated upon the physical structure of nonlinear interactions of the plasma flow and magnetic fluctuation. The result indicates that when the initial equilibrium profile is deformed by resistive diffusion, the radial flow is driven near the core of the plasma. As this flow forms a vortex structure and magnetic fluctuation grows radially, the dynamo electric field is spirally induced just inside the reversal surface and then the toroidal flux is increased. This dynamo electric field correlates to nonlinear evolution of the kinetic energy of m=1 mode, and the increase of the toroidal flux is originated in the growth process of the magnetic energy of this mode. Consequently, the RFP configuration can be sustained by the single-helicity evolution of m=1 mode alone, and the electric field induced by the interactions of the toroidal velocity and the radial magnetic field is the most dominant source on the dynamo action. (author)

  16. Liner of a thermonuclear pulse THETA-pinch reactor

    International Nuclear Information System (INIS)

    Baranov, G.A.; Izotov, E.N.; Karasev, B.G.; Komin, A.V.; Krivosheev, M.V.; Levashov, A.D.

    1975-01-01

    Some possible constructive solutions to the problem of fabrication of the theta-pinch reactor liner by the method of centrifugal casting in a casting mould are considered. A scheme for liner manufacturing is presented, which includes the following elements: 1) a casting mould of dielectric material presenting a hollow cylinder of 4 m in diam., 3 m in length and 12 t in weight, which rotates at 8 rps in the reactor chamber; 2) a system for heat protection of the casting mould; the volume heat of the mould is suggested to remove by gaseous helium flowing under pressure along axial cooling channels of 5 mm in diam.; the channels are evenly distributed throughout the thickness of the mould shell; 3) a system for preparation and supply of a liquid metal to the casting mould, the metal is being supplied into the casting mould from its both ends at a rate of 1.7 t of the melt per second; 4) a system for rotation of the mould, which comprises two gas turbines mounted on both ends of the mould and two main stop-radial slip supports with gas lubrication

  17. Does shaping bring an advantage for reversed field pinch plasmas?

    International Nuclear Information System (INIS)

    Guo, S.C.; Xu, X.Y.; Wang, Z.R.; Liu, Y.Q.

    2013-01-01

    The MHD–kinetic hybrid toroidal stability code MARS-K (Liu et al 2008 Phys. Plasmas 15 112503) is applied to study the shaping effects on magnetohydrodynamic (MHD) stabilities in reversed field pinch (RFP) plasmas, where both elongation and triangularity are taken into account. The ideal wall β (the ratio of the gaso-kinetic to magnetic pressures) limit set by the ideal kink mode/resistive wall mode in shaped RFP is investigated first, followed by a study of the kinetic damping on the resistive wall mode. Physics understanding of the results is provided by a systematic numerical analysis. Furthermore, the stability boundary of the linear resistive tearing mode in shaped RFP plasmas is computed and compared with that of the circular case. Finally, bootstrap currents are calculated for both circular and shaped RFP plasmas. Overall, the results of these studies indicate that the current circular cross-section is an appropriate choice for RFP devices, in the sense that the plasma shaping does not bring an appreciable advantage to the RFP performance in terms of macroscopic stabilities. In order to reach a steady-state operation, future RFP fusion reactors will probably need a substantial fraction of external current drives, due to the unfavourable scaling for the plasma-generated bootstrap current in the RFP configuration. (paper)

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

    International Nuclear Information System (INIS)

    Forest, C.B.; Chattopadhyay, P.K.; Nornberg, M.D.; Prager, S.C.; Thomas, M.A.; Harvey, R.W.; Ram, A.K.

    1999-04-01

    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-n parallel lower hybrid (LH) waves and electron Bernstein waves (EBWs)

  19. Results from TRX-2 slow field-reversed-theta-pinch

    International Nuclear Information System (INIS)

    Slough, J.T.; Harding, D.; Hoffman, A.L.

    1984-01-01

    FRCs have been successfully generated in the TRX-2 slow risetime theta pinch. Initial studies indicate that the flux trapping through field reversal is about as good (''50%) as on TRX-1, although the quarter cycle time of the main coil was increased from 3 to 10 μsec. Formation studies have been started using the programmed formation techniques developed on TRX-1. The plasma dynamics are very similar to those exhibited in the faster rise TRX-1 experiments. The formation phase shows the same high degree of symmetry and reproducibility that was observed in TRX-1. Equilibrium behaviour of the FRCs formed is very similar to that observed on TRX-1, as long as impurity content is kept low. T/sub e/ + T/sub i/ temperatures of 400 to 500 eV are obtained and confirmed by impurity line broadening and decay rates. Flux and particle lifetimes ≅ 100 μsec have been observed and show the same strong scaling with x/sub s/ that was observed on TRX-1

  20. Nonlinear dynamics of tearing modes in the reversed field pinch

    International Nuclear Information System (INIS)

    Holmes, J.A.; Carreras, B.A.; Diamond, P.H.; Lynch, V.E.

    1988-01-01

    The results of investigations of nonlinear tearing-mode dynamics in reversed field pinch plasmas are described. The linear instabilities have poloidal mode number m = 1 and toroidal mode numbers 10approx. < napprox. <20, and the resonant surfaces are therefore in the plasma core. The nonlinear dynamics result in dual cascade processes. The first process is a rapid m = 1 spectral broadening toward high n, with a simultaneous spreading of magnetic turbulence radially outward toward the field-reversal surface. Global m = 0 perturbations, which are driven to large amplitudes by the m = 1 instabilities, in turn trigger the m = 1 spectral broadening by back coupling to the higher n. The second process is a cascade toward large m and is mediated by m = 2 modes. The m = 2 perturbations have the structure of localized, driven current sheets and nonlinearly stabilize the m = 1 modes by transferring m = 1 energy to small-scale dissipation. The calculated spectrum has many of the qualitative features observed in experiments

  1. Studies of a poloidal divertor reversed field pinch

    International Nuclear Information System (INIS)

    Sarff, J.S.; Almagri, A.F.; Assadi, S.; Den Hartog, D.J.; Dexter, R.N.; Prager, S.C.; Sprott, J.C.

    1988-07-01

    An attempt has been made to form a reversed field pinch (RFP) in a poloidal divertor configuration which position the plasma far from a conducting wall. In this configuration, the plasma is localized within a magnetic separatrix formed by the combination of toroidal currents in the plasma and four internal aluminum rings. Plasmas were formed with plasma current /approximately/135 kA, toroidal field reversal lasting /approximately/1 msec, line-averaged density /approximately/1--2 /times/ 10 13 cm/sup /minus/3/ and central electron temperature /approximately/55 eV, but a large asymmetry in the magnetic field (δB/B /approximately/40%) onset at about the time the toroidal field reversed at the wall. Symmetric, poloidal divertor RFP equilibria were not formed. This behavior might be expected based on linear MHD stability analysis of a cylindrical plasma bounded by a large vacuum region and distant conducting wall. The symmetric equilibrium before the asymmetry develops and the asymmetry itself are described. 15 refs., 3 figs

  2. Electromagnetic Wave Propagation Through the ZR Z-Pinch Accelerator

    International Nuclear Information System (INIS)

    Rose, D. V.; Welch, D. R.; Madrid, E. A.; Miller, C. L.; Clark, R. E.; Stygar, W. A.; Struve, K.; Corcoran, P. A.; Whitney, B.

    2009-01-01

    A fully three-dimensional electromagnetic model of the major pulsed power components of the 26-MA ZR accelerator is presented. This large-scale simulation model tracks the evolution of electromagnetic waves through the intermediate storage capacitors, laser-triggered gas switches, pulse-forming lines, water switches, tri-plate transmission lines, and water convolute to the vacuum insulator stack. The plates at the insulator stack are coupled to a transmission line circuit model of the four-level magnetically-insulated transmission line section and post-hole convolutes. The vacuum section circuit model is terminated by either a short-circuit load or dynamic models of imploding z-pinch loads. The simulations results are compared with electrical measurements made throughout the ZR accelerator and good agreement is found, especially for times before and up to peak load power. This modeling effort represents new opportunities for modeling existing and future large-scale pulsed power systems used in a variety of high energy density physics and radiographic applications.

  3. Pellet injection in the RFP [Reversed Field Pinch

    International Nuclear Information System (INIS)

    Wurden, G.A.; Weber, P.G.; Munson, C.P.; Cayton, T.E.; Bunting, C.A.; Carolan, P.G.

    1988-01-01

    Observation of pellets injected into the ZT-40M Reversed Field Pinch has allowed a new twist on the usual tokamak ablation physics modeling. The RFP provides a strong ohmic heating regime with relatively high electron drift parameter (ξ/sub drift/ /approximately/ 0.2), in the presence of a highly sheared magnetic field geometry. In situ photos of the pellet ablation cloud using a grated-intensified CCD camera, as well as two-view integrated photos of the pellet trajectory show substantial modification of the original pellet trajectory, in both direction and speed. Depending on the launch geometry, increases in the initial 500 m/s pellet speed by 50% have been observed, and a ski jump deflector plate in the launch port has been used to counteract strong poloidal curvature. In contrast to the tokamak, the D/sub α/ light signature is strongest near the edge, and weaker in the plasma center. Additional information on ion temperature response to pellet injection with 20 μsec time resolution has been obtained using a 5-channel neutral particle analyzer (NPA). The energy confinement is transiently degraded while the beta is largely unchanged. This may be indicative of pellet injection into a high-beta plasma operating at fixed beta. 10 refs., 6 figs

  4. Phenomenological modeling of turbulence in Z-pinch implosions

    International Nuclear Information System (INIS)

    Thornhill, J.W.; Whitney, K.G.; Deeney, C.; LePell, P.D.

    1994-01-01

    A phenomenological investigation into the effects of magnetohydrodynamic (MHD) turbulence on the initial stagnation dynamics of aluminum wire array and argon gas puff Z-pinch implosions is performed. The increases that turbulence produces in the plasma viscosity, heat conductivity, and electrical resistivity are modeled by using multipliers for these quantities in one-dimensional (1-D) MHD calculations. The major effect of these increases is to soften the 1-D implosions by decreasing the densities that are achieved on axis at stagnation. As a consequence, a set of multipliers can be found that reasonably duplicates the average electron temperatures, ion densities, and mass of the K-shell emission region that were measured at stagnation for a variety of Physics International aluminum wire array and argon gas puff experiments. It is determined that the dependence of these measured quantities on the multipliers is weak once a level of enhancement is reached, where agreement between calculations and experiments is attained. The scaling of K-shell yield with load mass for a fixed implosion velocity is then reexamined, and the minimum load mass needed to efficiently produce K-shell emission by thermalization of kinetic energy is calculated for aluminum and argon using this phenomenological soft implosion modeling. The results show an upward shift in the minimum mass by a factor of 6 when compared to the original nonturbulent hard implosion calculations

  5. Opacity test using a neon-seeded theta pinch

    International Nuclear Information System (INIS)

    Thomson, D.B.

    1980-02-01

    Vacuum ultraviolet (VUV) emission from a neon-seeded high-density theta-pinch has been observed for comparison with theoretical radiation emission calculations. The plasma was created in a 25-cm-long theta-coil with 90-kG field having a 3.0-μs quarter period. A gas fill of 1 torr of helium + 2% neon was used. Observation of the HeII 4686 line/continuum ratio gave an electron temperature of 25 +- 4 eV. Shadowgraphs of the plasma radius, taken with a ruby laser, gave an electron density of 0.9 +- 0.09 x 10 18 cm -3 . The VUV emission was observed in radial view and with time resolution with a 2.2-m grazing-incidence monochromator equipped with a photomultiplier and p-terphenyl scintillator. Thin foils of carbon and aluminum were used as filters to absorb stray light and pass emission in the 44- to 100-A region

  6. Kinetic description of linear theta-pinch equilibria

    International Nuclear Information System (INIS)

    Batchelor, D.B.; Davidson, R.C.

    1975-01-01

    Equilibrium properties of linear theta-pinch plasmas are studied within the framework of the steady-state (o/x=0) Vlasov-Maxwell equations. The analysis is carried out for an infinitely long plasma column aligned parallel to an externally applied axial magnetic field Bsub(z)sup(ext)esub(z). Equilibrium properties are calculated for the class of rigid-rotor Vlasov equilibria, in which the th component distribution function (Hsub(perpendicular), Psub(theta), upsilonsub(z) depends on perpendicular energy H and canonical angular momentum Psub(theta), exclusively through the linear combination Hsub(perpendicular)-ωsub(j)Psub(theta), where ω;=const.=angular velocity of mean rotation. General equilibrium relations that pertain to the entire class of rigid-rotor Vlasov equilibria are discussed; and specific examples of sharp- and diffuse-boundary equilibrium configurations are considered. Rigid-rotor density and magnetic field profiles are compared with experimentally observed profiles. A general prescription is given for determining the functional dependence of the equilibrium distribution function on Hsub(perpendicular)-ωsub(j)Psub(theta) in circumstances, where the density profile or magnetic field profile is specified. (author)

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

    International Nuclear Information System (INIS)

    Perkins, F.W.; Hulse, R.A.

    1984-03-01

    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 10 14 cm -3 for beryllium, n/sub eo/ = 5 x 10 13 cm -3 for oxygen, n/sub eo/ = 1.0 x 10 13 cm -3 for iron, and n/sub eo/ = 0.5 x 10 13 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

  8. 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

  9. 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)

    1998-12-31

    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

  10. A new graphical method for Pinch Analysis applications: Heat exchanger network retrofit and energy integration

    International Nuclear Information System (INIS)

    Gadalla, Mamdouh A.

    2015-01-01

    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

  11. Un instrumento para analizar las actividades prácticas en la formación inicial del profesorado de Secundaria de Ciencias y Matemáticas desde la perspectiva de la sostenibilidad

    Directory of Open Access Journals (Sweden)

    José María Cardeñoso Domingo

    2015-01-01

    Full Text Available En este articulo se presenta un instrumento que refleja un sistema de analisis sobre la presencia de la sostenibilidad en las actividades practicas realizadas por los estudiantes durante el desarrollo de los diferentes modulos del “Master Universitario en Profesorado de Secundaria Obligatoria, Bachiller, Formacion Profesional y Ensenanza de Idiomas”. El objetivo de dicho instrumento, como recurso didactico, era promover el analisis y reflexion de los estudiantes sobre sus propias producciones. Este instrumento ha sido utilizado en diferentes momentos del proceso y esta configurado con una serie de categorias e indicadores que nos pueden dar claves para reconocer la presencia de los valores implicitos en la educacion para la sostenibilidad en las reflexiones y argumentaciones de los futuros profesores de Secundaria. Los indicadores de analisis inciden en la presencia de las competencias y valores relacionados con la Educacion para la Sostenibilidad.

  12. The Z-pinch as plasma lens for the focusing of heavy ion beams

    International Nuclear Information System (INIS)

    Elfers, M.

    1992-04-01

    In the present thesis the influence of a Z-pinch plasma on the shape of heavy-ion beams and the for the understanding of this interaction most important plasma parameters were studied. For this the Z-pinch at the heavy-ion accelerator UNILAC was operated. The magnet field gradients of up to (25 ± 3) T/m occuring in the Z-pinch lead to the plasma-lens effect - the focusing of a charged-particle beam traversing axially the Z-pinch. In this thesis for the first time the focusing of a heavy-ion beam by the azimutal magnetic field of a Z-pinch is described. Different beams with an original diameter of 10 mm were focused. The smallest measured beam diameter amounts to 1 mm half-width. The beam energy amounts to 11.4 MeV/u, which leads at gold as projectile matter to a beam energy of 2.25 GeV. (orig./HSI) [de

  13. A novel graphical technique for Pinch Analysis applications: Energy Targets and grassroots design

    International Nuclear Information System (INIS)

    Gadalla, Mamdouh A.

    2015-01-01

    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

  14. PBFA Z: A 20-MA Z-pinch driver for plasma radiation sources

    International Nuclear Information System (INIS)

    Spielman, R.B.; Breeze, S.F.; Deeney, C.

    1996-01-01

    Sandia National Laboratories is completing a major modification to the PBFA-II facility. PBFA Z will be capable of delivering up to 20 MA to a z-pinch load. It optimizes the electrical coupling to the implosion energy of z pinches at implosion velocities of ∼ 40 cm/μs. Design constraints resulted in an accelerator with a 0.12-Ω impedance, a 10.25-nH inductance, and a 120-ns pulse width. The design required new water transmission lines, insulator stack, and vacuum power feeds. Current is delivered to the z-pinch load through four self-magnetically-insulated vacuum transmission lines and a double post-hole convolute. A variety of design codes are used to model the power flow. These predict a peak current of 20 MA to a z-pinch load having a 2-cm length, a 2-cm radius, and a 15-mg mass, coupling 1.5 MJ into kinetic energy. Calculations are presented showing MJ x-ray outputs from tungsten wire-array z pinches. (author). 4 figs., 14 refs

  15. Fiber Z-pinch experiments and calculations in the finite Larmor radius regime

    International Nuclear Information System (INIS)

    Haines, M.G.; Dangor, A.E.; Coppins, M.

    1996-01-01

    The dense Z-pinch project at Imperial College is aimed at achieving radiative collapse to high density in a hydrogen plasma, and also to study plasmas close to controlled fusion conditions. To this end, the MAGPIE generator (2.4 MV, 1.25 Ω, and 200 ns) has been built and tested, and is now giving preliminary experimental data at 60% of full voltage for carbon and CD 2 fibers. These discharges are characterized by an initial radial expansion followed by the occurrence of m = 0 structures with transient X-ray emission from bright spots. Late in the discharge a disruption can occur, accompanied by hard X-ray emission from the anode due to an energetic electron beam and, in the case of CD 2 fibers, a neutron burst. Concomitant theoretical studies have solved the linear stability problem for a Z-pinch with large ion Larmor radii, showing that a reduction in growth rate of m = 0 and m = 1 modes to about 20% of the magnetohydrodynamic (MHD) value can occur for a parabolic density profile when the Larmor radius is optimally 20% of the pinch radius. Two-dimensional MHD simulations of Z-pinches in two extremes of focussed short-pulse laser-plasma interactions and of galactic jets reveal a nonlinear stabilizing effect in the presence of sheared flow. One-dimensional simulations show that at low line density the lower hybrid drift instability can lead to coronal radial expansion of a Z-pinch plasma. (Author)

  16. PBFA Z: A 60-TW/5-MJ Z-pinch driver

    International Nuclear Information System (INIS)

    Spielman, R.B.; Deeney, C.; Chandler, G.A.; Douglas, M.R.; Fehl, D.L.; Matzen, M.K.; McDaniel, D.H.; Nash, T.J.; Porter, J.L.; Sanford, T.W.; Seamen, J.F.; Stygar, W.A.; Struve, K.W.; Breeze, S.P.; McGurn, J.S.; Torres, J.A.; Zagar, D.M.; Gilliland, T.L.; Jobe, D.O.; McKenney, J.L.; Mock, R.C.; Vargas, M.; Wagoner, T.; Peterson, D.L.

    1997-01-01

    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

  17. PBFA Z: A 20-MA Z-pinch driver for plasma radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Spielman, R B; Breeze, S F; Deeney, C [Sandia Labs., Albuquerque, NM (United States); and others

    1997-12-31

    Sandia National Laboratories is completing a major modification to the PBFA-II facility. PBFA Z will be capable of delivering up to 20 MA to a z-pinch load. It optimizes the electrical coupling to the implosion energy of z pinches at implosion velocities of {approx} 40 cm/{mu}s. Design constraints resulted in an accelerator with a 0.12-{Omega} impedance, a 10.25-nH inductance, and a 120-ns pulse width. The design required new water transmission lines, insulator stack, and vacuum power feeds. Current is delivered to the z-pinch load through four self-magnetically-insulated vacuum transmission lines and a double post-hole convolute. A variety of design codes are used to model the power flow. These predict a peak current of 20 MA to a z-pinch load having a 2-cm length, a 2-cm radius, and a 15-mg mass, coupling 1.5 MJ into kinetic energy. Calculations are presented showing MJ x-ray outputs from tungsten wire-array z pinches. (author). 4 figs., 14 refs.

  18. Computational modeling of z-pinch-driven hohlraum experiments on Z

    International Nuclear Information System (INIS)

    Vesey, R.A.; Porter, J.L. Jr.; Cuneo, M.E.

    1999-01-01

    The high-yield inertial confinement fusion concept based on a double-ended z-pinch driven hohlraum tolerates the degree of spatial inhomogeneity present in z-pinch plasma radiation sources by utilizing a relatively large hohlraum wall surface to provide spatial smoothing of the radiation delivered to the fusion capsule. The z-pinch radiation sources are separated from the capsule by radial spoke arrays. Key physics issues for this concept are the behavior of the spoke array (effect on the z-pinch performance, x-ray transmission) and the uniformity of the radiation flux incident on the surface of the capsule. Experiments are underway on the Z accelerator at Sandia National laboratories to gain understanding of these issues in a single-sided drive geometry. These experiments seek to measure the radiation coupling among the z-pinch, source hohlraum, and secondary hohlraum, as well as the uniformity of the radiation flux striking a foam witness ball diagnostic positioned in the secondary hohlraum. This paper will present the results of computational modeling of various aspects of these experiments

  19. The design and implementation of a windowing interface pinch force measurement system

    Science.gov (United States)

    Ho, Tze-Yee; Chen, Yuanu-Joan; Chung, Chin-Teng; Hsiao, Ming-Heng

    2010-02-01

    This paper presents a novel windowing interface pinch force measurement system that is basically based on an USB (Universal Series Bus) microcontroller which mainly processes the sensing data from the force sensing resistance sensors mounted on five digits. It possesses several friendly functions, such as the value and curve trace of the applied force by a hand injured patient displayed in real time on a monitoring screen, consequently, not only the physician can easily evaluate the effect of hand injury rehabilitation, but also the patients get more progressive during the hand physical therapy by interacting with the screen of pinch force measurement. In order to facilitate the pinch force measurement system and make it friendly, the detail hardware design and software programming flowchart are described in this paper. Through a series of carefully and detailed experimental tests, first of all, the relationship between the applying force and the FSR sensors are measured and verified. Later, the different type of pinch force measurements are verified by the oscilloscope and compared with the corresponding values and waveform traces in the window interface display panel to obtain the consistency. Finally, a windowing interface pinch force measurement system based on the USB microcontroller is implemented and demonstrated. The experimental results show the verification and feasibility of the designed system.

  20. 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.

  1. Analisis Pembiayaan Kesehatan Keluarga Penderita Talasemia

    Directory of Open Access Journals (Sweden)

    Arif Kurniawan

    2013-04-01

    Full Text Available Pembiayaan kesehatan sekitar 146 (60% penderita talasemia di Banyumas, tahun 2011 ditanggung rumah tangga dalam bentuk pembayaran langsung (out of pocket payment. Penelitian ini bertujuan untuk menganalisis ability to pay, willingness to pay, dan need assessment pembiayaan kesehatan penderita talasemia di Kabupaten Banyumas. Jenis penelitian ini adalah observasional analitik dengan rancangan studi kasus. Penelitian ini menggunakan desain studi cross sectional dengan teknik pengambilan sampel simple random sampling. Jumlah sampel penelitian 30 responden yang mempunyai anggota keluarga penderita talasemia di Kabupaten Banyumas. Hasil penelitian menunjukkan keluarga penderita talasemia mempunyai ability to pay rata-rata adalah Rp34.448,8/bulan dan rata-rata willingness to pay pengobatan talasemia adalah Rp133.833,3/ bulan. Pola pembiayaan kesehatan talasemia di Kabupaten Banyumas menggunakan 93,3% Jaminan Kesehatan Masyarakat (Jamkesmas, 3,3% biaya sendiri, dan 3,3% asuransi kesehatan. Sebelum mendapatkan Jamkesmas, 90,0% responden membayar dengan out of pocket, berhutang, berhemat pada kebutuhan nonkesehatan, dan menjual perhiasan/sawah. Kebutuhan pelayanan kesehatan yang diharapkan keluarga penderita talasemia adalah konsultasi talasemia dan desain khusus ruang perawatan anak. Kebutuhan pembiayaan kesehatan keluarga penderita talasemia adalah uang transportasi ke rumah sakit sebagai bentuk biaya tidak langsung. Health financing of majority thalassemia patients, around 146 people (60% in Banyumas year 2011 is assured by Households in direct payments to health care providers (out-of-pocket payment. This study aimed to analyze the ability to pay, willingness to pay, and need assessment of health financing thalassemia in Banyumas. This research an analytic observation- Analisis Pembiayaan Kesehatan Keluarga Penderita Talasemia Health Financing Analysis of Thalassemia Patient Family Arif Kurniawan, Arih Diyaning Intiasari al with case study design

  2. Study of the internal structure, instabilities, and magnetic fields in the dense Z-pinch

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Vladimir V. [Univ. of Nevada, Reno, NV (United States)

    2016-08-17

    Z-pinches are sources of hot dense plasma which generates powerful x-ray bursts and can been applied to various areas of high-energy-density physics (HEDP). The 26-MA Z machine is at the forefront of many of these applications, but important aspects of HEDP have been studied on generators at the 1 MA current level. Recent development of laser diagnostics and upgrade of the Leopard laser at Nevada Terawatt Facility (NTF) give new opportunities for the dense Z-pinch study. The goal of this project is the investigation of the internal structure of the stagnated Z pinch including sub-mm and micron-scale instabilities, plasma dynamics, magnetic fields, and hot spots formation and initiation. New plasma diagnostics will be developed for this project. A 3D structure and instabilities of the pinch will be compared with 3D MHD and spectroscopic modeling and theoretical analysis. The structure and dynamics of stagnated Z pinches has been studied with x-ray self-radiation diagnostics which derive a temperature map of the pinch with a spatial resolution of 70-150 µm. The regular laser diagnostics at 532 nm does not penetrate in the dense pinch due to strong absorption and refraction in trailing plasma. Recent experiments at NTF showed that shadowgraphy at the UV wavelength of 266 nm unfolds a fine structure of the stagnated Z-pinch with unprecedented detail. We propose to develop laser UV diagnostics for Z pinches with a spatial resolution <5 μm to study the small-scale plasma structures, implement two-frame shadowgraphy/interferometry, and develop methods for investigation of strong magnetic fields. New diagnostics will help to understand better basic physical processes in Z pinches. A 3D internal structure of the pinch and characteristic instabilities will be studied in wire arrays with different configurations and compared with 3D MHD simulations and analytical models. Mechanisms of “enhanced heating” of Z-pinch plasma will be studied. Fast dynamics of stagnated

  3. Microinstabilities and turbulent transport in the reversed field pinch

    Science.gov (United States)

    Carmody, Daniel Richard

    The work presented in this thesis is concerned with addressing the nature of drift wave microturbulence in the reversed field pinch (RFP). Microturbulence is an important phenomenon and contributor to heat and particle transport in tokamaks, where it has been studied for several decades, but its role in the RFP is a rather new topic of study. As such, the nature of RFP drift waves and their relationship to their tokamak counterparts is still developing, and many of the results in this work are focused on addressing this challenge. Fundamental advances in microturbulence research have been made in recent decades through two parallel developments: the theoretical framework encompassed in the gyrokinetic model, and the computational power offered by massively-parallel, high-performance computing systems. Gyrokinetics is a formulation of kinetic theory in such a way that the fast timescale gyromotion of particles around magnetic field lines is averaged out. The implementation and use of RFP equilibrium models in gyrokinetic codes constitutes the bulk of this thesis. A simplified analytic equilibrium, the toroidal Bessel function model (TBFM), is used in the gyrokinetic code GYRO to explore the fundamental scaling properties of drift waves in the RFP geometry. Two drift wave instabilities, the ion temperature gradient (ITG) mode and the microtearing mode (MTM) are found to occur, and the relationship of their critical threshold in driving gradients and plasma beta is explored. The critical values in these parameters are found to be above those of similar tokamak cases by roughly a factor of the flux surface aspect ratio. The MTM is found to be stabilized by increasing the RFP pinch parameter theta, making it unlikely for it to unstable in the high-theta improved confinement pulsed poloidal current drive (PPCD) discharges. Efforts are also made to address microinstabilities in specific experimental discharges of the Madison Symmetric Torus (MST). A semi

  4. The TITAN Reversed-Field Pinch fusion reactor study

    International Nuclear Information System (INIS)

    1988-03-01

    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/m 2 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/m 2 ; 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. Self-consistent equilibria in cylindrical reversed-field pinch

    International Nuclear Information System (INIS)

    Lo Surdo, C.; Paccagnella, R.; Guo, S.

    1995-03-01

    The object of this work is to study the self-consistent magnetofluidstatic equilibria of a 2-region (plasma + gas) reversed-field pinch (RFP) in cylindrical approximation (namely, with vanishing inverse aspect ratio). Differently from what happens in a tokamak, in a RFP a significant part of the plasma current is driven by a dynamo electric field (DEF), in its turn mainly due to plasma turbulence. So, it is worked out a reasonable mathematical model of the above self-consistent equilibria under the following main points it has been: a) to the lowest order, and according to a standard ansatz, the turbulent DEF say ε t , is expressed as a homogeneous transform of the magnetic field B of degree 1, ε t =(α) (B), with α≡a given 2-nd rank tensor, homogeneous of degree 0 in B and generally depending on the plasma state; b) ε t does not explicitly appear in the plasma energy balance, as it were produced by a Maxwell demon able of extract the corresponding Joule power from the plasma. In particular, it is showed that, if both α and the resistivity tensor η are isotropic and constant, the magnetic field is force-free with abnormality equal to αη 0 /η, in the limit of vanishing β; that is, the well-known J.B. Taylor'result is recovered, in this particular conditions, starting from ideas quite different from the usual ones (minimization of total magnetic energy under constrained total elicity). Finally, the general problem is solved numerically under circular (besides cylindrical) symmetry, for simplicity neglecting the existence of gas region (i.e., assuming the plasma in direct contact with the external wall)

  6. Edge topology and flows in the reversed-field pinch

    International Nuclear Information System (INIS)

    Spizzo, G.; Agostini, M.; Scarin, P.; Vianello, N.; Cappello, S.; Puiatti, M. E.; Valisa, M.; White, R. B.

    2012-01-01

    Edge topology and plasma flow deeply influence transport in the reversed-field pinch as well as in all fusion devices, playing an important role in many practical aspects of plasma performance, such as access to enhanced confinement regimes, the impact on global power balance and operative limits, such as the density limit (Spizzo G. et al 2010 Plasma Phys. Control. Fusion 52 095011). A central role is played by the edge electric field, which is determined by the ambipolar constraint guaranteeing quasi-neutrality in a sheath next to the plasma wall. Its radial component is experimentally determined in RFX over the whole toroidal angle by means of a diagnostic set measuring edge plasma potential and flow with different techniques (Scarin P. et al 2011 Nucl. Fusion 51 073002). The measured radial electric field is used to construct the potential in the form Φ(ψ p , θ, ζ) (ψ p radial coordinate, θ, ζ angles), by means of the Hamiltonian guiding-centre code ORBIT. Simulations show that a proper functional form of the potential can balance the differential radial diffusion of electrons and ions subject to m = 0 magnetic island O- and X-points. Electrons spend more time in the X-points of such islands than in O-points; ions have comparatively larger drifts and their radial motion is more uniform over the toroidal angle. The final spatial distribution of Φ(ψ p , θ, ζ) results in a complex 3D pattern, with convective cells next to the wall. Generally speaking, an edge topology dominating parallel transport with a given symmetry brings about an edge potential with the same symmetry. This fact helps us to build a first step of a unified picture of the effect of magnetic topology on the Greenwald limit, and, more generally, on flows in the edge of RFPs and tokamaks. (paper)

  7. Design and experimental research on a self-magnetic pinch diode under MV

    Science.gov (United States)

    Pengfei, ZHANG; Yang, HU; Jiang, SUN; Yan, SONG; Jianfeng, SUN; Zhiming, YAO; Peitian, CONG; Mengtong, QIU; Aici, QIU

    2018-01-01

    A self-magnetic pinch diode (SMPD) integrating an anode foil-reinforced electron beam pinch focus and a small high-dose x-ray spot output was designed and optimized. An x-ray focal spot measuring system was developed in accordance with the principle of pinhole imaging. The designed SMPD and the corresponding measuring system were tested under ∼MV, with 1.75 × 2 mm2 oval x-ray spots (AWE defined) and forward directed dose 1.6 rad at 1 m. Results confirmed that the anode foil can significantly strengthen the electron beam pinch focus, and the focal spot measuring system can collect clear focal spot images. This finding indicated that the principle and method are feasible.

  8. Numerical studies of neon gas-puff Z-pinch dynamic processes

    International Nuclear Information System (INIS)

    Ning Cheng; Yang Zhenhua; Ding Ning

    2003-01-01

    Dynamic processes of neon gas-puff Z-pinch are studied numerically in this paper. A high temperature plasma with a high density can be generated in the process. Based on some physical analysis and assumption, a set of equations of one-dimensional Lagrangian radiation magneto-hydrodynamic (MHD) and its code are developed to solve the problem. Spatio-temporal distributions of plasma parameters in the processes are obtained, and their dynamic variations show that the major results are self-consistent. The duration for the plasma pinched to centre, as well as the width and the total energy of the x-ray pulse caused by the Z-pinch are in reasonable agreement with experimental results of GAMBLE-II. A zipping effect is also clearly shown in the simulation

  9. Collisional tearing in a field-reversed sheet pinch assuming nonparallel propagation

    International Nuclear Information System (INIS)

    Quest, K.B.; Coroniti, F.V.

    1985-01-01

    We examine the linear stability properties of the collisional tearing mode in a reversed-field sheet pinch assuming that the wave vector is not parallel to B, where B is the equilibrium magnetic field. We show that pressure balance in the direction of the equilibrium current requires a nonzero perturbed current component deltaJ/sub z/ that is driven toward tyhe center of the pinch. At the center of the pinch, deltaJ/sub z/ goes to zero, and momentum is balanced by coupling to the ion-acoustic mode. In order to achieve current closure, a large perturbed field-aligned current is generated that is strongly localized about the dissipative tearing layer. The relation of this work to the collisionless case is discussed

  10. Equilibrium, stability and heating of plasmas in linear and toroidal Extrap pinches

    International Nuclear Information System (INIS)

    Bonnevier, B.; Drake, J.R.; Dalhed, H.E.

    1983-01-01

    The Extrap scheme consists of a Z-pinch immersed in an octupole field. The total magnetic field has no component along the pinch axis. Globally stable Z-pinch equilibria with a distributed plasma current density and a duration of about 100 Alfven transit times have been observed in linear and toroidal sector experiments. Theoretical studies indicate that this stability can be the result of constraints introduced by the octupole field and the resulting separatrix of the total field, in combination with finite-Larmor-radius effects. A scheme for ICRF heating of the plasma in configurations with a magnetic neutral line, being applicable to Extrap and FRC, is analysed. Wave propagation arises owing to the Hall effect. Particle resonances are responsible for the absorption, owing to a high parallel wavenumber and a weak magnetic field. (author)

  11. A spin-liquid with pinch-line singularities on the pyrochlore lattice.

    Science.gov (United States)

    Benton, Owen; Jaubert, L D C; Yan, Han; Shannon, Nic

    2016-05-26

    The mathematics of gauge theories lies behind many of the most profound advances in physics in the past 200 years, from Maxwell's theory of electromagnetism to Einstein's theory of general relativity. More recently it has become clear that gauge theories also emerge in condensed matter, a prime example being the spin-ice materials which host an emergent electromagnetic gauge field. In spin-ice, the underlying gauge structure is revealed by the presence of pinch-point singularities in neutron-scattering measurements. Here we report the discovery of a spin-liquid where the low-temperature physics is naturally described by the fluctuations of a tensor field with a continuous gauge freedom. This gauge structure underpins an unusual form of spin correlations, giving rise to pinch-line singularities: line-like analogues of the pinch points observed in spin-ice. Remarkably, these features may already have been observed in the pyrochlore material Tb2Ti2O7.

  12. Method and apparatus for producing average magnetic well in a reversed field pinch

    International Nuclear Information System (INIS)

    Ohkawa, T.

    1983-01-01

    A magnetic well reversed field plasma pinch method and apparatus produces hot magnetically confined pinch plasma in a toroidal chamber having a major toroidal axis and a minor toroidal axis and a small aspect ratio, e.g. < 6. A pinch current channel within the plasma and at least one hyperbolic magnetic axis outside substantially all of the plasma form a region of average magnetic well in a region surrounding the plasma current channel. The apparatus is operated so that reversal of the safety factor q and of the toroidal magnetic field takes place within the plasma. The well-producing plasma cross section shape is produced by a conductive shell surrounding the shaped envelope and by coils. A shell is of copper or aluminium with non-conductive breaks, and is bonded to a thin aluminium envelope by silicone rubber. (author)

  13. Soft X-Ray Measurements of Z-Pinch-Driven Vacuum Hohlraums

    International Nuclear Information System (INIS)

    Baker, K.L.; Porter, J.L.; Ruggles, L.E.; Chandler, G.A.; Deeney, Chris; Varas, M.; Moats, Ann; Struve, Ken; Torres, J.; McGurn, J.; Simpson, W.W.; Fehl, D.L.; Chrien, R.E.; Matuska, W.; Idzorek, G.C.

    1999-01-01

    This article reports the experimental characterization of a z-pinch driven-vacuum hohlraum. The authors have measured soft x-ray fluxes of 5 x 10 12 W/cm 2 radiating from the walls of hohlraums which are 2.4--2.5 cm in diameter by 1 cm tall. The x-ray source used to drive these hohlraums was a z-pinch consisting of a 300 wire tungsten array driven by a 2 MA, 100 ns current pulse. In this hohlraum geometry, the z-pinch x-ray source can produce energies in excess of 800 kJ and powers in excess of 100 TW to drive these hohlraums. The x-rays released in these hohlraums represent greater than a factor of 25 in energy and more than a factor of three in x-ray power over previous laboratory-driven hohlraums

  14. Progress in Z-pinch research driven by the mega-ampere device SPEED2

    International Nuclear Information System (INIS)

    Pavez, Cristian; Soto, Leopoldo; Moreno, Jose; Sylvester, Gustavo; Tarifeno, Ariel

    2008-01-01

    Several pinch configurations have being studied at the Chilean Nuclear Energy Commission using the SPEED2 generator: plasma focus, gas embedded z-pinch and wire arrays. SPEED2 is a generator based on Marx technology (4.1 μF equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dt∼10 13 A/s). Currently the device is being operated at 70kJ stored energy producing a peak current of 2.4 MA in short circuit. In this work results related to studies in gas embedded z-pinch in deuterium and studies in wire arrays are presented.

  15. Theory of wire number scaling in wire-array Z pinches

    International Nuclear Information System (INIS)

    Desjarlais, M.P.; Marder, B.M.

    1999-01-01

    Pulsed-power-driven Z pinches, produced by imploding cylindrical arrays of many wires, have generated very high x-ray radiation powers (>200 TW) and energies (2 MJ). Experiments have revealed a steady improvement in Z-pinch performance with increasing wire number at fixed total mass and array radius. The dominant mechanism acting to limit the performance of these devices is believed to be the Rayleigh-Taylor instability which broadens the radially imploding plasma sheath and consequently reduces the peak radiation power. A model is presented which describes an amplification over the two-dimensional Rayleigh-Taylor growth rate brought about by kink-like forces on the individual wires. This amplification factor goes to zero as the number of wires approaches infinity. This model gives results which are in good agreement with the experimental data and provides a scaling for wire-array Z pinches. copyright 1999 American Institute of Physics

  16. Progress in Z-pinch research driven by the mega-ampere device SPEED2

    International Nuclear Information System (INIS)

    Pavez, Cristian; Soto, Leopoldo; Moreno, Jose; Tarifeno, Ariel; Sylvester, Gustavo

    2008-01-01

    Several pinch configurations have being studied at the Chilean Nuclear Energy Commission using the SPEED2 generator: plasma focus, gas embedded z-pinch and wire arrays. SPEED2 is a generator based on Marx technology (4.1 μF equivalent Marx generator capacity, 300 kV, 4 MA in short circuit, 187 kJ, 400 ns rise time, dI/dt∼10 13 A/s). Currently the device is being operated at 70kJ stored energy producing a peak current of 2.4 MA in short circuit. In this work results related to studies in gas embedded z-pinch in deuterium and studies in wire arrays are presented

  17. Observation of helical structure in a low energy plasma focus pinch

    International Nuclear Information System (INIS)

    Rout, R.K.; Shyam, A.

    1989-01-01

    Helical structure and hot spots were observed in a Mather-type plasma focus operated at 3 KJ of bank energy. The experiments were carried out with the help of a fast optical framing camera and two X-ray pin-hole cameras with different filters. It was observed that initially a conical pinch (with base diameter of 6 mm and length of 14 mm) with temperature of ≅ 10 2 eV was formed. This pinch disintegrated after ≅ 50 ns by a single lobe sausage instability into a central high temperature (≅ 10 3 eV) filament of 1 mm diameter and 8 mm length containing a high emissivity helical structure. This helix is probably responsible for generation of axial magnetic field and relaxation of the focus pinch. Hot spots of high X-ray intensity and temperature (≅ 10 3 eV) were also observed much beyond the filament region. (author)

  18. Kinetic theory of the sausage instability of a z-pinch

    International Nuclear Information System (INIS)

    Isichenko, M.B.; Kulyabin, K.L.; Yan'kov, V.V.

    1989-01-01

    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

  19. Los Alamos Compact Toroid, fast liner, and High-Density Z-Pinch programs

    International Nuclear Information System (INIS)

    Linford, R.K.; Hammel, J.E.; Sherwood, H.R.

    1982-01-01

    The compact Toroid and High Density Z-Pinch are two of the plasma configurations presently being studied at Los Alamos. This paper summarizes these two programs along with the recently terminated Fast Liner Program. Included in this discussion is an analysis of compact Toroid formation techniques showing the tearing and reconnection of the fields that separate the spheromak from the radial fields of the coaxial source, and the final equilibrium state of the elongated FRC in the theta-pinch coil. In addition the typical dimensions of the geometry of the Fast Liner experiments are delineated Z-pinch and electrode assembly is displayed as is a graphic of the temporal behavior of the current required for radial equilibrium. Spheromak is examined in terms of formation, gross stability, and equilibrium and field reversed configuration is discussed in terms of gross stability, equilibrium, and confinement scaling

  20. Application of 2-D Simulations to Z-Pinch Experiment Design and Analysis

    International Nuclear Information System (INIS)

    Peterson, D.L.; Bowers, R.L.; Matuska, W.; Chandler, G.A.; Deeney, C.; Derzon, M.S.; Matzen, M.K.; Mock, R.C.; Nash, T.J.; Sanford, T.W.L.; Spielman, R.B.; Struve, K.W.

    1998-01-01

    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

  1. Design and experimental research on a self-magnetic pinch diode under MV

    Institute of Scientific and Technical Information of China (English)

    Pengfei ZHANG; Yang HU; Jiang SUN; Yan SONG; Jianfeng SUN; Zhiming YAO; Peitian CONG; Mengtong QIU; Aici QIU

    2018-01-01

    A self-magnetic pinch diode (SMPD) integrating an anode foil-reinforced electron beam pinch focus and a small high-dose x-ray spot output was designed and optimized.An x-ray focal spot measuring system was developed in accordance with the principle of pinhole imaging.The designed SMPD and the corresponding measuring system were tested under ~MV,with 1.75 × 2 mm2 oval x-ray spots (AWE defined) and forward directed dose 1.6 rad at 1 m.Results confirmed that the anode foil can significantly strengthen the electron beam pinch focus,and the focal spot measuring system can collect clear focal spot images.This finding indicated that the principle and method are feasible.

  2. Characterization of aluminum x-pinch plasmas driven by the 0.5 TW Lion accelerator

    International Nuclear Information System (INIS)

    Qi, N.; Hammer, D.A.; Kalantantar, D.H.; Noonan, W.A.; Rondeau, G.; Workman, J.B.; Richardson, M.C.

    1989-01-01

    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

  3. Development of fast pulsed power driver for radiography and Z-pinch

    International Nuclear Information System (INIS)

    Qiu Aici; Sun Fengju

    2008-01-01

    Z-pinch and flash X-ray radiography have an important application in inertial confine fusion (ICF) and nuclear radiation effects simulation and high performance hydrodynamic test, etc. Z-pinch ICF and multi-pulse multi-axis high energy X-ray radiography put forward a huge challenge for pulsed power driver, so the direct-driven-load fast pulsed power driver are developed actively in home and abroard. The paper summarized the recent advances and developing trends of the fast pulsed power driver based on fast Marx(FMG) and fast linear transformer driver (LTD), and analysized the advantages and disadvantages and restricting factors about FMG and FLTD and their key technologies, then introduced the state-of-arts on the investigation in Northwest Institute of Nuclear Technology. In the end, the paper presented some advices and views about studying fast pulsed power driver applied to Z-pinch and flash X-ray radiography in home. (authors)

  4. Scintillator power meter applied on Z-pinch plasma soft X-ray yield measurement

    International Nuclear Information System (INIS)

    Zhang Siqun; Huang Xianbin; Li Jing; Dan Jiakun; Li Jun; Yang Libing; Cui Mingqi; Zhao Yidong

    2010-01-01

    This paper presents the configuration and measuring parameters of scintillator power meter applied in Z-pinch plasma soft X-ray yield measurement on Yang accelerator. It also introduces the calibration experiment on BSRF, and analyzes the defect of the power meter from calibration results, the possible errors and feasible method for correcting the errors. The measuring results are revised according to spectrum acquired from Dante spectrometer. The revised discrepancy of two instruments is decreased from over 30% to subter-15%. Finally, the result of yield measurement of the puff Z-pinch X-ray radiation is reported as well, i.e., hundreds of Joule, multigigawatt levels of soft X ray radiation were produced by puff Z-pinch on Yang accelerator. (authors)

  5. 3D modeling of instabilities in multi-wire Z pinches

    International Nuclear Information System (INIS)

    Haill, T.A.; Desjarlais, M.P.; Marder, B.M.; Robinson, A.C.

    1998-01-01

    Recent success in generating large x-ray energies and powers from large wire-number Z pinch arrays has revived a strong interest in MHD and magneto-Rayleigh-Taylor (RT) instabilities. Two-dimensional r-z simulations of Z pinches typically start calculations with a preformed plasma sheath and seed RT instabilities with a random density perturbation. The magnitude of the random density perturbation is tuned so that the calculated x-ray radiation pulse matches the amplitude and pulse-width of experimentally measured data. While these calculations have been extremely useful in understanding the effect of RT instabilities on experiments, they do not capture all of the three-dimension structure seen in experimental images and are not truly predictive in nature. To remedy this shortcoming Sandia is developing a 3D nature of Z pinch dynamics, namely the merger of arrays of wires into a plasma sheath

  6. Current driven instabilities of the kinetic shear Alfven wave: application to reversed field pinches and spheromaks

    International Nuclear Information System (INIS)

    Meyerhofer, D.D.; Perkins, F.W.

    1984-04-01

    The kinetic Alfven wave is studied in a cylindrical force-free plasma with self-consistent magnetic fields. This equilibrium represents a reversed field pinch or a spheromak. The stability of the wave is found to depend on the ratio of the electron drift velocity to the Alfven velocity. This ratio varies inversely with the square root of the plasma line density. The critical line density using the Spitzer-Harm electron distribution function is found for reversed field pinches with deuterium plasmas to be approximately 2 x 10 18 m -1 and is 5 x 10 17 m -1 in spheromaks with hydrogen plasmas. The critical line density is in reasonable agreement with experimental data for reversed field pinches

  7. ANALISIS DEL COMPORTAMIENTO DEL USUARIO WEB

    OpenAIRE

    ROMAN ASENJO, PABLO ENRIQUE; ROMAN ASENJO, PABLO ENRIQUE

    2011-01-01

    Desde los orígenes de la Web en el CERN, ha existido una pregunta recurrente entre los investigadores y desarrolladores: ¿Cual es la estructura y contenido correcto para que un sitio Web atraiga y/o retenga a sus visitantes? En parte, la respuesta a esta interrogante, se encuentra fuertemente relacionada con una mayor comprensión de las motivaciones que posee un usuario al visitar un sitio. Tradicionalmente, se han utilizado algoritmos de minería de datos (Machine Learning) para extraer...

  8. ANALISIS DEL COMPORTAMIENTO DEL USUARIO WEB

    OpenAIRE

    ROMAN ASENJO, PABLO ENRIQUE

    2011-01-01

    Desde los orígenes de la Web en el CERN, ha existido una pregunta recurrente entre los investigadores y desarrolladores: ¿Cual es la estructura y contenido correcto para que un sitio Web atraiga y/o retenga a sus visitantes? En parte, la respuesta a esta inteJTogante, se encuentra fuertemente relacionada con una mayor comprensión de las motivaciones que posee un usuario al visitar un sitio. Tradicionalmente, se han utilizado algoritmos de minería de datos (Machine Learning) para extraer pa...

  9. Stabilization of long wavelength sausage and kink modes of a Z-pinch by nonlinear radial oscillations

    International Nuclear Information System (INIS)

    Bud'ko, A.B.; Karlson, E.T.; Liberman, M.A.

    1992-01-01

    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

  10. Comparative Studies of Traditional (Non-Energy Integration and Energy Integration of Catalytic Reforming Unit using Pinch Analysis

    Directory of Open Access Journals (Sweden)

    M. Alta

    2012-12-01

    Full Text Available Energy Integration of Catalytic Reforming Unit (CRU of Kaduna Refinery and petrochemicals Company Kaduna Nigeria was carried out using Pinch Technology. The pinch analysis was carried out using Maple. Optimum minimum approach temperature of 20 °C was used to determine the energy target. The pinch point temperature was found to be 278 °C. The utilities targets for the minimum approach temperature were found to be 72711839.47 kJ/hr and 87105834.43 kJ/hr for hot and cold utilities respectively. Pinch analysis as an energy integration technique was found to save more energy and utilities cost than the traditional energy technique. Key words: Pinch point, CRU, Energy Target, Maple

  11. Target design for high fusion yield with the double Z-pinch-driven hohlraum

    International Nuclear Information System (INIS)

    Vesey, R. A.; Herrmann, M. C.; Lemke, R. W.; Desjarlais, M. P.; Cuneo, M. E.; Stygar, W. A.; Bennett, G. R.; Campbell, R. B.; Christenson, P. J.; Mehlhorn, T. A.; Porter, J. L.; Slutz, S. A.

    2007-01-01

    A key demonstration on the path to inertial fusion energy is the achievement of high fusion yield (hundreds of MJ) and high target gain. Toward this goal, an indirect-drive high-yield inertial confinement fusion (ICF) target involving two Z-pinch x-ray sources heating a central secondary hohlraum is described by Hammer et al. [Phys. Plasmas 6, 2129 (1999)]. In subsequent research at Sandia National Laboratories, theoretical/computational models have been developed and an extensive series of validation experiments have been performed to study hohlraum energetics, capsule coupling, and capsule implosion symmetry for this system. These models have been used to design a high-yield Z-pinch-driven ICF target that incorporates the latest experience in capsule design, hohlraum symmetry control, and x-ray production by Z pinches. An x-ray energy output of 9 MJ per pinch, suitably pulse-shaped, is sufficient for this concept to drive 0.3-0.5 GJ capsules. For the first time, integrated two-dimensional (2D) hohlraum/capsule radiation-hydrodynamics simulations have demonstrated adequate hohlraum coupling, time-dependent radiation symmetry control, and the successful implosion, ignition, and burn of a high-yield capsule in the double Z-pinch hohlraum. An important new feature of this target design is mode-selective symmetry control: the use of burn-through shields offset from the capsule that selectively tune certain low-order asymmetry modes (P 2 ,P 4 ) without significantly perturbing higher-order modes and without a significant energy penalty. This paper will describe the capsule and hohlraum design that have produced 0.4-0.5 GJ yields in 2D simulations, provide a preliminary estimate of the Z-pinch load and accelerator requirements necessary to drive the system, and suggest future directions for target design work

  12. Analisis Komoditi Unggulan Subsektor Tanaman Pangan di Sumatera Utara Tahun 2010 – 2014

    OpenAIRE

    Sinaga, Terry Praganda

    2016-01-01

    Tujuan penelitian ini adalah untuk mengetahui perkembangan produksi komoditi tanaman pangan selama periode tersebut sehingga dapat menganalisis komoditi subsektor tanaman pangan yang menjadi unggulan di Sumatera Utara. Komoditi unggulan tersebut juga dijabarkan untuk setiap kabupatem/kota yang ada di Sumatera Utara. Metode yang digunakan yaitu secara Convenience Sampling, dan metode analisis data dengan menggunakan analisis Location Quotient. Hasil penelitian menyimpulkan ba...

  13. ANALISIS KINERJA KEUANGAN PERUSAHAAN PT. ASURANSI JIWASRAYA (PERSERO) CABANG SULAWESI SELATAN

    OpenAIRE

    ARIANTY, ASTRI

    2012-01-01

    ANALISIS KINERJA KEUANGAN PERUSAHAAN PT. ASURANSI JIWASRAYA (PERSERO) CABANG SULAWESI SELATAN COMPANY FINANCIAL PERFORMANCE ANALYSIS PT. INSURANCE JIWASRAYA (LIMITED) SOUTH BRANCH SULAWESI Astri Arianty Prof. Dr. H. Muhammad Ali, SE., M.S Drs. Armayah Sida, M.Si Analisis terhadap kinerja keuangan perusahaan sangat penting dilakukan untuk mengetahui sejauh mana tingkat pencapaian yang telah diperoleh perusahaan sebagaimana tujuan perusahaan dalam menjalankan proses produk...

  14. Compressibility Effects in the Dynamics of the Reversed-Field Pinch

    International Nuclear Information System (INIS)

    Onofri, M.; Malara, F.; Veltri, P.

    2008-01-01

    We study the reversed-field pinch through the numerical solution of the compressible magnetohydrodynamic equations. Two cases are investigated: In the first case the pressure is derived from an adiabatic condition, and in the second case the pressure equation includes heating terms due to resistivity and viscosity. In the adiabatic case a single helicity state is observed, and the reversed-field pinch configuration is formed for short time intervals and is finally lost. In the nonadiabatic case the system reaches a multiple helicity state, and the reversal parameter remains negative for a longer time. The results show the importance of compressibility in determining the large scale dynamics of the system

  15. Particle pinch with fully noninductive lower hybrid current drive in Tore Supra.

    Science.gov (United States)

    Hoang, G T; Bourdelle, C; Pégourié, B; Schunke, B; Artaud, J F; Bucalossi, J; Clairet, F; Fenzi-Bonizec, C; Garbet, X; Gil, C; Guirlet, R; Imbeaux, F; Lasalle, J; Loarer, T; Lowry, C; Travère, J M; Tsitrone, E

    2003-04-18

    Recently, plasmas exceeding 4 min have been obtained with lower hybrid current drive (LHCD) in Tore Supra. These LHCD plasmas extend for over 80 times the resistive current diffusion time with zero loop voltage. Under such unique conditions the neoclassical particle pinch driven by the toroidal electric field vanishes. Nevertheless, the density profile remains peaked for more than 4 min. For the first time, the existence of an inward particle pinch in steady-state plasma without toroidal electric field, much larger than the value predicted by the collisional neoclassical theory, is experimentally demonstrated.

  16. Plasma channel and Z-pinch dynamics for heavy ion transport

    Energy Technology Data Exchange (ETDEWEB)

    Ponce-Marquez, David [Univ. of California, Berkeley, CA (United States)

    2002-01-01

    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 ~ 2 cm. Results also show that typical main bank discharge plasma densities reach 1017 cm-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

  17. Investigation of intense XUV emission of nitrogen-puff Z-pinch with small energy input

    International Nuclear Information System (INIS)

    Raus, J.; Krejci, A.; Piffl, V.

    1992-01-01

    Light elements like nitrogen or carbon are suggested as optimum working media for small Z-pinches (several kJ energy input). It is shown that such elements can be ionized up to K-shell ionization stages not only in hot-spots, but also in the bulk plasma. The yield of nitrogen K-shell radiation (about 10 J/shot) is therefore substantially higher than that of the conventionally used neon. In addition to pinch physics and radiation dynamics, such radiation could be of interest for applications in the 'water window' spectral region. (author) 1 tab., 4 figs., 8 refs

  18. Interferometric characterization of density dynamics of an ultradense Z-pinch plasma

    International Nuclear Information System (INIS)

    Ackenhusen, J.G.; Bach, D.R.

    1979-01-01

    We have measured the spatially and temporally resolved density in a Z-pinch plasma by holographic interferometry. The high electron density (4 x 10 19 e/cm 3 ), short density scale length (100 μm), and low temperature (about 20 eV) make the plasma source suitable for simulation of laser-pellet interaction experiments at 10.6-μm laser wavelengths. A cinema of density evolution, indicating plasma pinching and subsequent relaxation, provides an experimental view of plasma dynamics which is then compared to simple theoretical models

  19. Reversed-field pinch configuration with minimum energy and finite beta

    International Nuclear Information System (INIS)

    Zhang Peng

    1989-01-01

    The reversed-field pinch (RFP) configuration has been studied for the case of finite beta. Suydam's condition and the sufficient criterion have been used to examine this configuration. Results of numerical calculations show that the critical value of the pinch parameter Θ for the appearance of the reverse toroidal field increases as the β-value increases. The critical value of Θ for the helical state increases with β as well. Suydam's and Robinson's stability regions increase and shift towards higher values of Θ with increasing β. Theoretical results for finite β coincide with recent RFP experimental results

  20. Pinch-off syndrome: transection of implantable central venous access device.

    Science.gov (United States)

    Sugimoto, Takuya; Nagata, Hiroshi; Hayashi, Ken; Kano, Nobuyasu

    2012-11-30

    As the population of people with cancer increases so does the number of patients who take chemotherapy. Majority of them are administered parentally continuously. Implantable central venous catheter device is a good choice for those patients; however, severe complication would occur concerning the devices. Pinch-off syndrome is one of the most severe complications. The authors report a severe case of pinch-off syndrome. The patient with the implantable central venous device could not take chemotherapy because the device occluded. Further examination revealed the transection of the catheter. The transected fragment of the catheter in the heart was successfully removed by using a loop snare placed through the right femoral vein.