WorldWideScience

Sample records for plants controlador digital

  1. SIMULACIÓN DE CONTROLADORES DIGITALES SIMULATION OF DIGITAL CONTROLLERS

    Directory of Open Access Journals (Sweden)

    Carlos Álvarez G

    2009-12-01

    Full Text Available El presente trabajo tiene como objetivo la implementación de controladores digitales en un entorno de simulación controlado, para esto se desarrolla una plataforma de hardware que permite ejecutar los programas en lenguaje C generados en una estación de trabajo. Estos programas corresponden al controlador y a la planta que son generados por un software que genera dichos programas a partir de sus parámetros de modelación aplicando teoría de control digital sobre procesos reales.This paper describes an implementation of digital controllers in a simulation environment for including a hardware platform for running programs generated on a workstation. These programs for both the controller and the plant are generated by software based on parameters using digital control theory for real processes.

  2. Digital viscosity controller for fossil power plants; Controlador digital de viscosidad para plantas termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Bautista B, Amberto; Ocampo P, Carlos; Gutierrez A, Ruben; Madinaveitia V, Miguel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    Upon the need of increasing the efficiency of the existing fossil power plants in Mexico, the Instrumentation and Control Department of the Instituto de Investigaciones Electricas (IIE) designed and built a viscosity controller to enhance the fuel oil heating process. The system strategy, that allows the control either by temperature or viscosity considers, as an important element, the changing characteristics of the supplied fuels. The equipment that is utilized forms apart of the line Acquisition and Control System (ACS) developed at the same Institute, that has been successfully applied in other systems. [Espanol] Ante la necesidad de aumentar la eficiencia de las plantas termoelectricas existentes en Mexico, el Departamento de Instrumentacion y Control, del Instituto de Investigaciones Electricas (IIE), diseno y construyo un controlador de viscosidad para mejorar el proceso de calentamiento del aceite combustible. La estrategia del sistema, que permite controlar ya sea por viscosidad o por temperatura, considera como elemento importante las caracteristicas cambiantes de los combustibles suministrados. El equipo que se utiliza forma parte de la linea SAC (sistema de adquisicion y control), desarrollada en el mismo Instituto, que se ha aplicado satisfactoriamente en otros sistemas.

  3. Digital viscosity controller for fossil power plants; Controlador digital de viscosidad para plantas termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Bautista B, Amberto; Ocampo P, Carlos; Gutierrez A, Ruben; Madinaveitia V, Miguel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1989-12-31

    Upon the need of increasing the efficiency of the existing fossil power plants in Mexico, the Instrumentation and Control Department of the Instituto de Investigaciones Electricas (IIE) designed and built a viscosity controller to enhance the fuel oil heating process. The system strategy, that allows the control either by temperature or viscosity considers, as an important element, the changing characteristics of the supplied fuels. The equipment that is utilized forms apart of the line Acquisition and Control System (ACS) developed at the same Institute, that has been successfully applied in other systems. [Espanol] Ante la necesidad de aumentar la eficiencia de las plantas termoelectricas existentes en Mexico, el Departamento de Instrumentacion y Control, del Instituto de Investigaciones Electricas (IIE), diseno y construyo un controlador de viscosidad para mejorar el proceso de calentamiento del aceite combustible. La estrategia del sistema, que permite controlar ya sea por viscosidad o por temperatura, considera como elemento importante las caracteristicas cambiantes de los combustibles suministrados. El equipo que se utiliza forma parte de la linea SAC (sistema de adquisicion y control), desarrollada en el mismo Instituto, que se ha aplicado satisfactoriamente en otros sistemas.

  4. COMPARACIÓN DE DESEMPEÑO ENTRE CONTROLADORES FUZZY Y CONTROLADORES PROPORCIONALES

    Directory of Open Access Journals (Sweden)

    Sergio L. Martínez

    2012-01-01

    Full Text Available El objetivo de este trabajo es comparar el desempeño de dos controladores fuzzy y un controlador proporcional. La variable controlada es el nivel de un tanque con descarga gravitatoria. Para realizar el estudio, se desarrolló un simulador dinámico implementado en Simulink® de MatLab®. Para cada controlador estudiado, se evaluó la respuesta producida ante un cambio escalón en el set point. Para realizar una comparación válida, los controladores fueron ajustados para producir offset iguales. Los resultados obtenidos muestran que los sistemas basados en heurísticas (controladores fuzzy pueden ser tanto o más convenientes que aquellos basados en conocimiento determinístico (el controlador proporcional. Si bien el controlador proporcional actúa con mayor velocidad, los controladores fuzzy mejoran los valores de algunos de los índices más importantes de desempeño, como los sobrepicos, las oscilaciones y el factor de ripple.

  5. Controladores neuronales en robótica evolutiva

    OpenAIRE

    Fernández León, José A.; Acosta, Gerardo

    2004-01-01

    Este trabajo consiste en el estudio de las características más relevantes de la metodología denominada Robótica Evolutiva, en cuanto a la construcción de controladores neuronales evolutivos genéticamente determinados. Dichos controladores son aplicados a un robot tipo Khepera para llevar a cabo tareas (por ejemplo: planificación de trayectorias en navegación de robots) dentro de un entrono no conocido previamente. Los controladores propuestos están basados en controladores neuronales de tiemp...

  6. Control de un sistema eólico-fotovoltaico utilizando un controlador fuzzy; Control of a wind-photovoltaic system using a controller fuzzy

    Directory of Open Access Journals (Sweden)

    Alfredo G M Gámez López

    2011-02-01

    Full Text Available En este artículo, se prueba de manera virtual, un controlador basado en lógica difusa para un sistema híbrido degeneración de energía. La simulación digital emplea como herramienta el Labview, obteniéndose resultadosgráficos descriptivos de la acción del controlador, así como la interfaz gráfica representativa del comportamientodel sistema. In this article is tested a virtual controller using fuzzy logic for a hybrid system of power generation.LABVIEW is used as a digital simulation tool obtaining descriptive graphical results of the action of the driveras well as a graphical interface of the behavior of the system.

  7. Programación de controladores de dispositivos en Windows

    OpenAIRE

    Gutiérrez Peón, Pablo

    2013-01-01

    Este documento pretende servir como toma de contacto en la construcción de controladores de dispositivos para el sistema operativo Windows. Se repasa brevemente el entorno Windows para continuar con los componentes básicos en la realización de controladores. Para finalizar se da una pequeña guía con los pasos a seguir al desarrollar controladores de dispositivos. La información contenida en este documento procede del siguiente manual: Art Baker y Jerry Lozano. The Windows 2...

  8. Controlador Inteligente De Transporte

    Directory of Open Access Journals (Sweden)

    Alejandro J. Cabrera Sarmiento

    2011-03-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} En el presente trabajo se expone la concepción, desarrollo e implementación de un Controlador Inteligente de Transporte, el cual se encarga del control de una intersección semaforizada. La estructura hardware del controlador ha sido dividida en dos clases de tarjetas: las Tarjetas de Luces, encargadas de activar las señales para las indicaciones en una intersección (luces, sonido, etc. y la Tarjeta de Control, encargada del control de la intersección gobernando hasta cuatro tarjetas de luces con las cuales se comunica, así como de establecer comunicación con un nivel jerárquico superior. Ambas tarjetas han sido desarrolladas en base a microcontroladores de 8 bits de Microchip. El firmware de ambos tipos de tarjetas ha sido desarrollado y puesto a punto utilizando PIC C de CCS. El desarrollo de este controlador, de prestaciones superiores a los existentes actualmente en el país, permite su inserción en un Sistema Inteligente de Transporte (SIT que se encuentra en fase de desarrollo.

  9. Controlador electrònic programable per vehicles de maquinària pesada

    OpenAIRE

    Gómez Areste, Sergi

    2017-01-01

    Disseny d'un controlador electrònic per maquinària pesada basat en sistemes de lògica reconfigurable. Diseño de un controlador electrónico para maquinaria pesada basado en sistemas de lógica reconfigurable. Designing an electronic controller for heavy machinery systems based on reconfigurable logic.

  10. Núcleo de Control: Controladores modulares en entornos distribuidos

    Directory of Open Access Journals (Sweden)

    Raúl Simarro

    2016-04-01

    Full Text Available Resumen: En este artículo se describe una estrategia de control distribuida, utilizando elementos empotrados, mediante un middleware de control denominado núcleo de control, en el que se implementan controladores digitales de altas prestaciones, diseñados de forma modular, en sistemas con capacidad de cómputo limitada. Se presenta una metodología tanto para la obtención de una métrica que permita la comparación de los distintos modos de funcionamiento ante pérdidas de datos, como para la elección de los parámetros de los controladores a implementar en cada nodo del sistema distribuido de control. Se presentan varios modos de funcionamiento que permite adaptar el sistema desarrollado a distintas situaciones. El trabajo se completa con la implementación de la simulación del sistema distribuido y su prueba sobre un proceso real. Abstract: In this paper a distributed control strategy described using embedded items, using a control middleware called control kernel, in which high performance digital controllers designed in a modular way, on systems with limited computational capabilities are implemented. A methodology is presented for both obtaining a metric that allows comparison of different modes of operation for any loss of data, and for the choice of parameters of the controllers implemented in each node of the distributed control system. Multi-mode which allows adapting the system developed at different situations arise. The work was completed with the implementation of distributed system simulation and test of a real process. Palabras clave: Sistemas empotrados, control predictivo basado en modelo, control de sistemas distribuidos, Keywords: Embedded systems, model predictive control, distributed control systems.

  11. Controlador empotrado en FPGA para Sistema Inteligente de Transporte

    Directory of Open Access Journals (Sweden)

    Alejandro José Cabrera Sarmiento

    2011-11-01

    Full Text Available 1024x768 Normal 0 21 false false false ES X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} En el presente trabajo se expone la concepción, desarrollo e implementación de un controlador empotrado en un FPGA de Xilinx para ser utilizado en un Sistema Inteligente de Transporte (SIT. La estructura hardware del controlador está basada en la utilización de diversos módulos de propiedad intelectual del sistema de procesamiento MicroBlaze y el soporte de software está basado en la utilización del sistema operativo Petalinux. El controlador empotrado dispone de interfaces Ethernet, USB, UART, SPI e I2C para la comunicación con los diferentes niveles jerárquicos del SIT. Ha sido implementado sobre una placa de desarrollo basada en un FPGA Spartan3E de 1.200 k compuertas, ocupando un 59% de sus recursos configurables. El resto de los recursos disponibles en el FPGA permite, además de la posible actualización del controlador, la implementación hardware de algoritmos que requieren una alta velocidad de procesamiento.

  12. Control de velocidad de un motor de inducción utilizando un controlador Fuzzy

    Directory of Open Access Journals (Sweden)

    Madelín Lima Álvarez

    2011-03-01

    Full Text Available Se realiza la simulación del sistema de control de velocidad del motor de inducción. Se parte del enfoquevectorial y de un sistema de coordenadas adecuado a su futura utilización, utilizando para esto el lenguaje desimulación de sistemas dinámicos Simulink. En cuanto a la simulación del método de control vectorial porcampo orientado se ha empleado el denominado método de control vectorial indirecto. El control de la velocidaddel motor se simuló utilizando un controlador Fuzzy, comparándose posteriormente estos resultados con losobtenidos mediante la utilización de un controlador PI digital.  This work carries out the simulation of speed control of induction motor. It is based on the field orientation theoryand on a system of coordinates adapted to its future use. The language that has been used for the simulation ofdynamics systems is Simulink. The indirect method of the field orientation control theory was used in themathematical analysis of the induction motor. The speed control of the induction motor was simulated using aFuzzy controller and these results were compared with those obtained by means of the use of a PI digitalcontroller.

  13. Linealización de sistemas VSC-HVDC para el diseño de un controlador PI vectorial

    Directory of Open Access Journals (Sweden)

    Nelson Díaz Aldana

    2014-01-01

    Full Text Available Los sistemas VSC-HVDC son muy utilizados para la transmisión de energía en redes de interconexión eléctrica. Uno de los principales problemas que poseen estos sistemas es la complejidad de su modelo matemático, lo que conlleva grandes dificultades para el diseño de controladores que permitan la regulación de parámetros como la tensión DC de transmisión, así como la potencia activa y reactiva del sistema VSC-HVDC. En este artículo se presenta la linealización de un sistema VSC-HVDC y el posterior diseño de un controlador lineal PI vectorial a partir del modelo linealizado. Adicionalmente, se proponen dos estrategias para la validación de este tipo de controladores, la primera consiste en un único controlador PI para regular los estados del sistema para cada VSC, la segunda consiste en el diseño de controladores PI vectoriales independientes para la regulación de cada estado del VSC.

  14. Controlador en Modo Deslizante para Sistemas Fotovoltaicos Conectados a la Red Eléctrica

    Directory of Open Access Journals (Sweden)

    D. Arcos

    2012-11-01

    Full Text Available Se describe el análisis, modelamiento y diseño de un lazo de control para sistemas fotovoltaicos (PV conectados a la red eléctrica. Se aborda el modelado de un panel fotovoltaico; el diseño de un convertidor elevador (Boost y su lazo de control mediante un controlador proporcional-integral PI de corriente y un controlador en modo deslizante; y finalmente el diseño de un inversor DC-AC de una fase. Se realiza una descripción de la dinámica del convertidor Boost y de las ecuaciones para el diseño del controlador en modo deslizante y del inversor de una sola fase. El sistema propuesto ha sido simulado utilizando las herramientas de la librería SimPowerSystems de Matlab/Simulink.

  15. Análisis de estabilidad de controladores borrosos tipo Mamdani mediante el cálculo del exponente de Lyapunov

    Directory of Open Access Journals (Sweden)

    Leonardo-Alonso Martínez Rivera

    2015-10-01

    Full Text Available Resumen: Determinar la estabilidad de los controladores, ya sea mediante simulaciones o mediante técnicas analíticas, es vital en su diseño e implantación. El método analítico de estabilidad en el sentido de Lyapunov requiere encontrar una función candidata, como criterio suficiente pero no necesario para tal fin. Esta función candidata es elusiva para los controladores borrosos. Se propone, como posible solución a este problema, cuantificar la estabilidad de los controladores borrosos mediante el exponente de Lyapunov (EL calculado numéricamente. Las series de tiempo de la cuales se calculan los exponentes de Lyapunov son obtenidas de la salida de diversos controladores borrosos tipo Mamdani en lazo cerrado con la dinámica de la planta no lineal estabilizada en una región de operación admisible. Los experimentos fueron llevados al cabo mediante la implantación del método numérico en la plataforma MATLAB, integrándolo con datos provenientes de la simulación de diversos controladores borrosos. La planta a controlar es el sistema carro-péndulo invertido modelado con la formulación Euler Lagrange. En cada experimento se obtuvo la serie de tiempo correspondiente a la señal de control y se calculó el exponente de Lyapunov. Aunque se observan variaciones en magnitud, el exponente calculado resulta negativo en todos los casos. Esto indica que los controladores difusos tipo Mamdani empleados son sistemas disipativos. Como trabajo futuro se esboza el empleo del EL en control adaptable. Abstract: In order to design and implement any type of controller, their stability analysis is pivotal. At this regard, Lyapunov's analytical method consists in finding a candidate function as a sufficient but not necessary condition to validate the stability of the controller. In the case of fuzzy controllers such a candidate function is not always found, leading to an uncertainty about their stability. To

  16. Controlador fuzzy de código aberto para uso em controladores programáveis.

    OpenAIRE

    Edinei Peres Legaspe

    2012-01-01

    Sistemas de controle fuzzy são amplamente empregados na indústria de controle de processos. Normalmente controlando variáveis analógicas, tais como pressão, temperatura, vazão, posição e velocidade. Hoje existem diversas soluções de mercado que permitem o uso da lógica fuzzy em CPs (Controladores programáveis). Porém essas soluções são proprietárias e de custo elevado. Adicionalmente existe a norma IEC 61131-7, introduzida no ano de 2000, que especifica sistemas fuzzy em CPs, onde a mesma def...

  17. Control de velocidad de un motor de CD con un controlador PID Wavenet

    Directory of Open Access Journals (Sweden)

    Abraham Christian Pedroza Araujo

    2014-01-01

    Full Text Available El controlador más utilizado actualmente en la industria es el controlador PID. Sin embargo, el algoritmo PID lineal tiene bajo desempeño cuando el proceso a controlar presenta dinámicas complejas como zonas muertas y características no lineales. El funcionamiento del controlador PID en general, se basa en la actuación en forma proporcional, integral y derivativa sobre la señal de error e(t, definida como e(t = yref(t - y(t, con la finalidad de efectuar la señal de control u(t que manipula la salida del proceso en forma deseada como se muestra la Figura 1. Figura 1. Esquema de un control clásico. Figura 1. Esquema de un control clásico. Las constantes kp ki kd son las ganancias del PID. Existen distintas técnicas analíticas y experimentales con el fin de sintonizar esas ganancias. Una alternativa a este problema de sintonización es el controlador PID wavenet, donde por medio de una wavenet y un filtro IIR se estima la salida del sistema a controlar, lo cual se utiliza para re-sintonizar las ganancias de un PID discreto, todo esto en línea. Esta es la alternativa que se emplea en el presente trabajo de investigación y enfocada a la simulación y control de un motor de cd obteniendo resultados.

  18. Fuzzy controller of speed-power of a synchronous micro generator; Controlador difuso de velocidad-potencia de un microgenerador sincrono

    Energy Technology Data Exchange (ETDEWEB)

    Martinez Alvarado, Raziel

    2002-11-01

    This thesis shows the design and implementation of a speed-power fuzzy-logic controller. The controller implementation was carried out on the Schrage motor-synchronous generator set. The synchronous alternator is rated 7 kVA, 220 V, 1800 rpm, 60 Hz. Two PI like fuzzy-logic controllers were developed with 9 and 25 rules. The controllers use the speed or power error and its integral as input variables and as an output the control signal from the brush-positioner of the Schrage motor. At the controller design stage, the anfis (adaptive-network-based fuzzy inference system) learning and structure procedure was used for tuning up parameters of the membership functions used on the designed fuzzy controllers. These controllers are first-order Sugeno-type. The designed controllers were tested on the motor-generator set under loaded and no-loaded conditions. It was found that PI-9 rules fuzzy-logic controller had better performance on both operating conditions. [Spanish] En este trabajo de tesis se presenta el diseno e implementacion de un controlador difuso de velocidad-potencia, para un grupo motor Schrage-generador sincrono de 7 kVA, 220 V, 1800 rpm, 60 Hz. Se implementaron controladores difusos del tipo PI de 9 y 25 reglas. Estos controladores utilizan como variables de entrada el error y la integral del error, de velocidad o potencia segun corresponda, y como variable de salida la senal de control del posicionador de las escobillas del motor Schrage. En la etapa de diseno de los controladores, se utilizo la estructura y el procedimiento de aprendizaje anfis (Sistema de Inferencia Difuso Basado en Redes Adaptables, por sus siglas en ingles) para sintonizar los parametros de las funciones de membresia de los controladores difusos, los cuales son del tipo Sugeno de primer orden. Con la finalidad de validar los controladores disenados, se realizaron pruebas experimentales al grupo motor-generador en condiciones de vacio y carga. Se encontro que el controlador difuso tipo

  19. Controladores multivariables para un vehículo autónomo terrestre: Comparación basada en la fiabilidad del software

    Directory of Open Access Journals (Sweden)

    Norberto Cañas

    2014-04-01

    Full Text Available Resumen: Se presenta en este artículo la comparación de tres controladores de velocidad (regulador cuadrático lineal-LQR-, proporcional integral derivativo-PID-y borroso con la intención de determinar cuál de ellos ofrece mejor fiabilidad desde una perspectiva software. Para realizar las pruebas necesarias se utilizaron versiones mutantes de controladores bien ajustados, en los que se inyectaron defectos que simulaban errores de programación. Los controladores fueron diseñados para operar un vehículo autónomo terrestre y fueron ajustados por medio de un algoritmo genético.Dado el elevado número de pruebas a efectuar se decidió construir un simulador multicomputador con el que se realizaron más de 90000 ensayos. En cada uno de los ensayos se sometió a cada controlador mutante a la realización de un recorrido, de unos 20 minutos de duración máxima, sobre un suelo ligeramente ondulado. Con los datos obtenidos se generaron las curvas de fiabilidad por el procedimiento de Kaplan-Meier, lo cual permitió la comparación de controladores objetivo del estudio.De las curvas de fiabilidad del software obtenidas se deduce que, en las condiciones experimentales planteadas, el controlador LQR ofrece el mejor comportamiento, el segundo lugar le corresponde al controlador PID y el tercero al controlador borroso. Abstract: In this paper, three multivariable speed controllers (linear quadratic regulator-LQR, proportional integral derivative - PID, and Fuzzy were compared with each other to find which one has the best software reliability. The reliability tests were conducted on perturbed controllers with injected faults, simulating typical programmer errors. These controllers were designed to operate in an autonomous ground vehicle, and they were tuned by using a genetic algorithm. Given the large number of tests to be performed it was decided to build a multi-computer simulator in which they were carried out more than 90000 essays. In each of

  20. Clonación artificial de controladores basados en técnicas de inteligencia artificial

    Directory of Open Access Journals (Sweden)

    Javier Antonio Ballesteros

    2004-11-01

    Full Text Available En el presente articulo se expone un avance de anteproyecto, sobre técnicas de inteligencia Artificial, su aplicación a procesos industriales y herramientas para realizar simulación. Se citan algunos trabajos en los cuales hay resultados, y que prestan un soporte lógico para continuar con el desarrollo del proyecto. Ademas, se analiza, la función que cumple el controlador el cual debe ser preciso, confiable y que a su vez reduzca costos. Por estas razones se tomó como base del proyecto un controlador que posea estas características para que se puedan aplicar técnicas de lnteligencia Artificial y poder realizar Ia colación artificial.

  1. Estudo comparativo de controladores de Mamdani e Sugeno para controle de tráfego em interseções isoladas

    Directory of Open Access Journals (Sweden)

    Michelle Andrade

    2009-10-01

    Full Text Available

    Na definição de um controlador

     

    fuzzy que modele o conhecimento do especialista e promova o controle desejado de um determinado sistema, o projetista precisa selecionar, inicialmente, o tipo básico de controlador a ser projetado. Isto é, precisa definir se o controlador será do tipo proposto por Mamdani ou Sugeno. Na literatura são encontrados controladores semafóricos fuzzy dos dois tipos sem que, no entanto, referência seja feita às razões que levaram à adoção de um tipo em detrimento do outro. Visando cobrir essa lacuna, este trabalho analisa as principais características dos dois tipos de controladores, e compara as respostas e os efeitos dos mesmos no controle de diferentes volumes de tráfego em uma interseção isolada. Os resultados mostram que o controlador de Sugeno apresenta nítidas vantagens sobre o de Mamdani para a aplicação considerada.

  2. PROJETO DE UM CONTROLADOR PROPORCIONAL-INTEGRAL PARA O SISTEMA DE CONTROLE DE QUALIDADE DO AR E DE UM NOVO SISTEMA DE CONTROLE HVAC

    Directory of Open Access Journals (Sweden)

    Millene Caroline Albino de Oliveira

    2015-09-01

    Full Text Available Uma sala do Perlstein Hall, da Illinois Institute of Techonology, (Chicago, IL, USA possui um sistema de aquecimento, ventilação e ar condicionado (em inglês – HVAC equipado com um sensor de gás carbônico, cujo intuito é regular diretamente a qualidade do ar e assegurar que a sala esteja em condições aceitáveis. Este procedimento, porém, pode colocar uma carga extra no sistema HVAC e aumentar o consumo de energia. Desta forma, o objetivo principal do trabalho foi o desenvolvimento e a aplicação de uma estratégia de controle de temperatura e concentração de CO2 para o sistema em questão, utilizando um controlador Proporcional-Integral (PI. Dados coletados em testes realizados na sala foram utilizados para a estimação dos parâmetros das funções de transferência e dos controladores. Inicialmente, os controladores foram testados separadamente e, em seguida, em conjunto. Pode-se observar que o controlador PI obteve bons resultados, apesar do overshoot e oscilações do sistema já observados pela literatura, conseguindo atingir o set point desejado de temperatura de 70°F e de concentração de CO2 de 150 ppm. Palavras-chave: HVAC, Controle, controlador PI.

  3. Voltage controller design for air conditioning; Diseno de controlador de voltaje para aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Andrade, R; Lopez Villalobos, J.J; Valderrama Chairez, J; Ramirez, R.L. [Instituto Tecnologico de Nuevo Leon, Guadalupe, Nuevo Leon (Mexico)]. E-mails: roxana_garciaandrade@yahoo.com; xe2n@yahoo.com.mx; jose.valderrama@ieee.org

    2013-03-15

    This paper discusses the design of a voltage controller for an air conditioning system in order to generate additional power in activation or startup of the system, for which as a first stage is presented the modeling power generation of electric current through alternative means, such as solar energy. The results of this study will be the basis for development of the physical prototype of this system controller. [Spanish] El presente trabajo trata sobre el diseno de un controlador de voltaje para un sistema de aire acondicionado con el fin de generar energia adicional en la activacion o arranque de dicho sistema, para lo cual como primer fase se presenta el modelado de la generacion de corriente electrica mediante medios alternos, como lo es la energia solar. Los resultados de este trabajo seran la base para desarrollo del prototipo fisico de este sistema controlador.

  4. Revolution of Nuclear Power Plant Design Through Digital Technology

    International Nuclear Information System (INIS)

    Zhang, L.; Shi, J.; Chen, W.

    2015-01-01

    In the digital times, digital technology has penetrated into every industry. As the highest safety requirement standard, nuclear power industry needs digital technology more to breed high quality and efficiency. Digital power plant is derived from digital design and the digitisation of power plant transfer is an inevitable trend. This paper introduces the technical solutions and features of digital nuclear power plant construction by Shanghai Nuclear Engineering Research & Design Institute, points out the key points and technical difficulties that exist in the process of construction and can serve as references for further promoting construction of digital nuclear power plant. Digital technology is still flourishing. Although many problems will be encountered in construction, it is believed that digital technology will make nuclear power industry more safe, cost-effective and efficient. (author)

  5. Arquitectura multi-controlador con transferencia sin salto para procesos con conmutación de modos

    Directory of Open Access Journals (Sweden)

    Nagore Iriondo

    2013-04-01

    Full Text Available Resumen: Los sistemas con conmutación de modos se definen como aquéllos que pueden exhibir diferente comportamiento dinámico en función del estado en que se encuentran. Pueden por tanto ser descritos por un conjunto finito de subsistemas dinámicos y una lógica que rige la conmutación entre ellos. Una alternativa para su control es la arquitectura multi-controlador con supervisión ya que permite utilizar controladores de modo diferentes y alcanzar así múltiples objetivos de control. Pero la conmutación de controladores suele tener como consecuencia la aparición de saltos o transitorios derivados que pueden ser inaceptables. Este tipo de sistemas y problemática son frecuentes en diferentes áreas de aplicación industrial, en donde la tecnología de control más utilizada es el Controlador Lógico Programable (PLC. Es por ello que el objetivo de este trabajo es presentar un método de diseño e implementación de un mecanismo de transferencia sin salto (BT en una arquitectura multi-modo y multi-bucle para sistemas con conmutación de modos, en PLC y en conformidad con el estándar IEC 61131-3. La estrategia BT se basa en que controladores de modos candidatos a conmutar realicen un seguimiento a los controladores activos, siendo la detección del estado de operación actual y de los posibles estados siguientes, clave en la definición de la forma de ejecución de los algoritmos de control que componen la arquitectura. Se presentan también los pasos del diseño de la arquitectura completa así como resultados experimentales que validan la arquitectura. Abstract: Switched mode systems are defined as those represented by a finite set of linear subsystems and a set of logic rules orchestrating the switching among them. A set of dynamic subsystems together with a logical system that orchestrates the switching among them could be used in order to describe it. An alternative to control them is a supervisory multi-mode controller architecture

  6. Application of digital control in Japanese PWR Plants

    International Nuclear Information System (INIS)

    Taguchi, S.; Kondo, Y.; Teranishi, S.; Matsumiya, M.; Takashima, M.; Nagai, T.

    1986-01-01

    More reliable and flexible control system to improve the plant availability and operability is constantly demanded. In order to answer the demands, digital control systems are being applied to Japanese PWR plants. Microprocessor-based digital control systems are widely used in other industries and show good performance. The digital control system has been already applied to the chemical and volume control system and the radioactive waste disposal system in the operating plants. These systems have been working as expected and demonstrating good performances. The digital control system for the reactor control system, which is the main control system of the PWR plants, is being developed. The design of the system has been already finished and the verification/validation process is now in progress

  7. General digitalized system on nuclear power plants

    International Nuclear Information System (INIS)

    Akagi, Katsumi; Kadohara, Hozumi; Taniguchi, Manabu

    2000-01-01

    Hitherto, instrumentation control system in a PWR nuclear power plant has stepwisely adopted digital technology such as application of digital instrumentation control device to ordinary use (primary/secondary system control device, and so on), application of CRT display system to monitoring function, and so forth, to realize load reduction of an operator due to expansion of operation automation range, upgrading of reliability and maintenance due to self-diagnosis function, reduction of mass in cables due to multiple transfer, and upgrading of visual recognition due to information integration. In next term PWR plant instrumentation control system, under consideration of application practice of conventional digital technology, application of general digitalisation system to adopt digitalisation of overall instrumentation control system containing safety protection system, and central instrumentation system (new type of instrumentation system) and to intend to further upgrade economics, maintenance, operability/monitoring under security of reliability/safety is planned. And, together with embodiment of construction program of the next-term plant, verification at the general digitalisation proto-system aiming at establishment of basic technology on the system is carried out. Then, here was described on abstract of the general digitalisation system and characteristics of a digital type safety protection apparatus to be adopted in the next-term plant. (G.K.)

  8. Diseño de un controlador difuso supervisor para la regulación de un convertidor conmutado elevador

    Directory of Open Access Journals (Sweden)

    Spartacus Gomáriz

    2008-11-01

    Full Text Available En este trabajo, se diseña un controlador difuso del tipo Takagi-Sugeno-Kang (TSK para un regulador elevador conmu­tado DC-DC que opera a diferentes tensiones en estado estacionario. Este controlador realiza tareas de supervisión mediante su característica zonal. Por un lado, el controlador asigna diferentes leyes lineales de control acorde al valor de tensión de régimen estacionario y de los límites de aplicación a perturbación en pequeña señal. Por otra parte, el controlador asegura un arranque correcto para alcanzar el valor deseado de tensión de estado estacionario, por medio de una adecuada saturación del modulador de ancho de pulso (PWM de acuerdo con los principios de control en modo deslizamiento. Como resultado, se logra un comportamiento ecualizado en pequeña señal y un arranque controlado para diferentes tensiones de estado estacionario; por tanto, se amplían las características del regulador. Se presentan resultados de simulación y experimen­tales realizados sobre un regulador elevador controlado por corriente, operando sobre dos valores de tensión diferentes de estado estacionario que validan el diseño. / A complete design of a Takagi-Sugeno-Kang (TSK fuzzy controller for a PWM boost DC-DC switching regulator operating at different steady-state voltages is presented. This controller performs a supervisory role through its region characteristic. On the one hand, the controller assigns different linear control laws according to the steady-state voltage value and limits their application to small-signal perturbations. On the other hand, the controller ensures a proper start-up to reach the desired steady-state voltage by means of properly saturating the PWM according to sliding-mode control principles. As a result, both an equalized small-signal behavior and a controlled start-up are achieved for different steady-state voltages, thus extending the features of the regulator. Simulation and experimental results

  9. Localization of equipment for digital plant protection system

    Energy Technology Data Exchange (ETDEWEB)

    Koo, I. S.; Park, H. Y.; Lee, C. K. and others

    2000-10-01

    The objective of this project lies on the development of design requirements, establishment of structure and manufacture procedures, development of the software verification and validation(V and V) techniques of the digital plant protection system. The functional requirements based on the analog protection system and digital design requirements are introduced, the processor and system bus for safety grade equipment are selected and the interface requirements and the design specification have been developed in order to manufacture the quick prototype of the digital plant protection system. The selection guidelines of parts, software development and coding and testing for digital plant protection system have been performed through manufacturing the quick prototype based on the developed design specification. For the software verification and validation, the software review plan and techniques of verification and validation have been researched. The digital validation system is developed in order to verify the quick prototype. The digital design requirements are reviewed by the software safety plan and V and V plans. The formal methods for verifying the safety-grade software are researched, then the methodology of formal analysis and testing have been developed.

  10. Localization of equipment for digital plant protection system

    International Nuclear Information System (INIS)

    Koo, I. S.; Park, H. Y.; Lee, C. K. and others

    2000-10-01

    The objective of this project lies on the development of design requirements, establishment of structure and manufacture procedures, development of the software verification and validation(V and V) techniques of the digital plant protection system. The functional requirements based on the analog protection system and digital design requirements are introduced, the processor and system bus for safety grade equipment are selected and the interface requirements and the design specification have been developed in order to manufacture the quick prototype of the digital plant protection system. The selection guidelines of parts, software development and coding and testing for digital plant protection system have been performed through manufacturing the quick prototype based on the developed design specification. For the software verification and validation, the software review plan and techniques of verification and validation have been researched. The digital validation system is developed in order to verify the quick prototype. The digital design requirements are reviewed by the software safety plan and V and V plans. The formal methods for verifying the safety-grade software are researched, then the methodology of formal analysis and testing have been developed

  11. Trends in digital I and C for nuclear power plants

    International Nuclear Information System (INIS)

    Cook, B.M.

    2000-01-01

    Over the past decade, large-scale digital I and C systems have been installed on nuclear power plants as the original systems for plant operations. Examples of these include Sizewell B in the United Kingdom and Temelin NPP in the Czech Republic. Now, this digital technology is being used for replacement and upgrade systems such as those for Ringhals Unit 2 in Sweden and the Kewaunee plant in the United States. Such a digital upgrade is being planned for the Dukovany NPP in the Czech Republic. As the experience base grows with this digital technology on nuclear power plants, certain trends are developing in the application practices and licensing of these systems. This paper discusses these trends and suggests adaptations that may become necessary in the classical roles of vendors, regulators and plant operators. (author)

  12. Digital protection in power plants. Electrical unit and line protection. Digital protection systems for NPP

    International Nuclear Information System (INIS)

    Kaczmarek, A.

    2000-01-01

    In this presentation author deals with the digital protection systems for nuclear power plants. The evolution of protection devices, protection concept for power plants, concept of functional redundancy, references for digital protection, benefits for the customer well as concept fault recorder are presented. (author)

  13. Implementation considerations for digital control systems in power plants: Final report

    International Nuclear Information System (INIS)

    Shah, S.C.; Lehman, L.L.; Sarchet, M.M.

    1988-09-01

    Conversion of nuclear power plants fron analog to digital control systems will require careful design, testing, and integration of the control algorithms, the software which implements the algorithms, the digital instrumentation, the digital communications network, and analog/digital device interfaces. Digital control systems are more flexible than their analog counterparts, and therefore greater attention must be paid by the customer to all stages of the control system design process. This flexibility also provides the framework for development of significant safety and reliability are inherant aspects of the chosen design processes. Digital control algorithms are capable of improving their performance by on-line self-tuning of the control parameters. It is therefore incumbant on system designers to choose self-tuning algorithms for power plant control. Implementation of these algorithms in software required a careful software design and development process to minimize errors in interpretation of the engineering design and prevent the inclusion of programming errors during software production. Digital control system and communications software must exhibit sufficient ''fault tolerance'' to maintain some level of safe plant operation or execute a safe plant shutdown in the event of both hard equipment failures and the appearance of software design faults. A number of standardized digital communications protocols are available to designers of digital control systems. These standardized digital communications protocols provide reliable fault tolerant communication between all digital elements of the plant control system and can be implemented redundantly to further enhance power plant operational safety. 5 refs., 11 figs., 1 tab

  14. Formación de robots móviles mediante el uso de controladores

    Directory of Open Access Journals (Sweden)

    Adriana Riveros Guevara

    2013-12-01

    Full Text Available El manejo de sistemas multi-robots, ha adquirido gran atención en las últimas décadas, destacándose en aplicaciones tales como la elaboración de mapas, el transporte de objetos e incluso el rescate de personas. Teniendo en cuenta esta motivación, se realizó la búsqueda de trabajos que abordaron el tema, encontrando diferentes tipos de controladores aplicados a estos sistemas manteniendo la configuración líder-seguidor.

  15. Análisis y comparación entre un controlador PI difuso y un controlador PI óptimo convencional para un conversor reductor

    Directory of Open Access Journals (Sweden)

    Lina Morales Laguado

    2009-09-01

    Full Text Available nente. Tal tipo de dispositivos de electrónica de potencia convierten una tensión continua a otra de menor magnitud y cuyas ca- racterísticas de no linealidad son evidenciadas. Se presentan entonces, dos técnicas de control no lineal, la primera propuesta es un control óptimo PI (error proporcional e integral del error convencional, basado en la minimización del criterio ITSE (integral del cuadrado del error ponderado en el tiempo. Para ello se obtiene un modelo de la planta en un punto de operación. La se- gunda propuesta es un control difuso cuyos conjuntos de entrada y salida son también definidos minimizando el criterio ITSE en el sistema general, y estableciendo como entradas el error proporcional y la integral del error. A continuación se realiza una va- riación de la carga para establecer la eficiencia del sistema con los dos controladores mencionados. Se debe tener en cuenta que este tipo de sistemas no debe presentar sobretensiones considerables, ya que puede ocasionar daño en él. En este sentido, los parámetros encontrados en el diseño de los dos controladores corresponden a una metodología analítica y descriptiva. Los resultados obtenidos en simulación, y estableciendo como figura de mérito el índice de desempeño mencionado (ITSE y el con- sumo de potencia, muestra que la respuesta del sistema para el control difuso presenta un mayor consumo de potencia que el control óptimo, mientras que el ITSE obtenido es mayor para el control óptimo que para el difuso. Se concluye que la explora- ción de este tipo de conversores, utilizando técnicas de control no lineal y minimizando los diferentes índices de desempeño, es aplicable.

  16. Diseño de un Controlador Híbrido en Ambientes Virtuales para Teleoperación Robótica

    Directory of Open Access Journals (Sweden)

    Cecilia Garcia

    2010-07-01

    Full Text Available Resumen: En este artículo se presenta el diseño e implementación de un controlador híbrido para un sistema de teleoperación robótico. La estructura de control de bajo nivel fue diseñada para controlar tanto la posición del manipulador remoto como así también la fuerza de interacción. En la estación local se consideró la dinámica del operador humano y en el sitio remoto se consideró un modelo elástico para el entorno. El controlador supervisor es diseñado utilizando la teoría de sistemas híbridos y en particular se empleó un autómata como herramienta de modelado para el controlador de eventos discretos. Los resultados teóricos se validan a través de una plataforma de simulación de un robot comercial. Palabras Clave: Telerrobótica, Control de Robots, Sistemas de Eventos Discretos, Simulación, Diseño de Sistemas de Control

  17. Digital Biomass Accumulation Using High-Throughput Plant Phenotype Data Analysis.

    Science.gov (United States)

    Rahaman, Md Matiur; Ahsan, Md Asif; Gillani, Zeeshan; Chen, Ming

    2017-09-01

    Biomass is an important phenotypic trait in functional ecology and growth analysis. The typical methods for measuring biomass are destructive, and they require numerous individuals to be cultivated for repeated measurements. With the advent of image-based high-throughput plant phenotyping facilities, non-destructive biomass measuring methods have attempted to overcome this problem. Thus, the estimation of plant biomass of individual plants from their digital images is becoming more important. In this paper, we propose an approach to biomass estimation based on image derived phenotypic traits. Several image-based biomass studies state that the estimation of plant biomass is only a linear function of the projected plant area in images. However, we modeled the plant volume as a function of plant area, plant compactness, and plant age to generalize the linear biomass model. The obtained results confirm the proposed model and can explain most of the observed variance during image-derived biomass estimation. Moreover, a small difference was observed between actual and estimated digital biomass, which indicates that our proposed approach can be used to estimate digital biomass accurately.

  18. An evaluation method of fault-tolerance for digital plant protection system in nuclear power plants

    International Nuclear Information System (INIS)

    Lee, Jun Seok; Kim, Man Cheol; Seong, Poong Hyun; Kang, Hyun Gook; Jang, Seung Cheol

    2005-01-01

    In recent years, analog based nuclear power plant (NPP) safety related instrumentation and control (I and C) systems have been replaced to modern digital based I and C systems. NPP safety related I and C systems require very high design reliability compare to the conventional digital systems so that reliability assessment is very important. In the reliability assessment of the digital system, fault tolerance evaluation is one of the crucial factors. However, the evaluation is very difficult because the digital system in NPP is very complex. In this paper, the simulation based fault injection technique on simplified processor is used to evaluate the fault-tolerance of the digital plant protection system (DPPS) with high efficiency with low cost

  19. Estimation of reliability on digital plant protection system in nuclear power plants using fault simulation with self-checking

    International Nuclear Information System (INIS)

    Lee, Jun Seok; Kim, Suk Joon; Seong, Poong Hyun

    2004-01-01

    Safety-critical digital systems in nuclear power plants require high design reliability. Reliable software design and accurate prediction methods for the system reliability are important problems. In the reliability analysis, the error detection coverage of the system is one of the crucial factors, however, it is difficult to evaluate the error detection coverage of digital instrumentation and control system in nuclear power plants due to complexity of the system. To evaluate the error detection coverage for high efficiency and low cost, the simulation based fault injections with self checking are needed for digital instrumentation and control system in nuclear power plants. The target system is local coincidence logic in digital plant protection system and a simplified software modeling for this target system is used in this work. C++ based hardware description of micro computer simulator system is used to evaluate the error detection coverage of the system. From the simulation result, it is possible to estimate the error detection coverage of digital plant protection system in nuclear power plants using simulation based fault injection method with self checking. (author)

  20. Clonación artificial de controladores basados en técnicas de inteligencia artificial

    OpenAIRE

    Javier Antonio Ballesteros; Alonso Guevara

    2004-01-01

    En el presente articulo se expone un avance de anteproyecto, sobre técnicas de inteligencia Artificial, su aplicación a procesos industriales y herramientas para realizar simulación. Se citan algunos trabajos en los cuales hay resultados, y que prestan un soporte lógico para continuar con el desarrollo del proyecto. Ademas, se analiza, la función que cumple el controlador el cual debe ser preciso, confiable y que a su vez reduzca costos. Por estas razones se tomó como base del proyecto un con...

  1. Ampliación del benchmark de diseño de controladores para el cabeceo de un helicóptero

    Directory of Open Access Journals (Sweden)

    Mario García-Sanz

    2007-01-01

    Full Text Available Resumen: El presente documento complementa al aparecido en RIAI Vol. 3, Num. 2, pp 111-116, 2006, sobre el control del ángulo de cabeceo de un helicóptero de laboratorio. Ofrece un modelo más detallado del sistema que permitirá obtener controladores avanzados. Además, la función de evaluación del benchmark es modificada para ponderar equilibradamente los objetivos de control. El benchmark ampliado se propone como Premio Mathworks al mejor diseño para el banco de pruebas “Ingeniería de control” 2007, para el que se abre un nuevo plazo de presentación de trabajos. Palabras clave: Diseño de controladores, benchmark, control de helicópteros

  2. Proceedings: Distributed digital systems, plant process computers, and networks

    International Nuclear Information System (INIS)

    1995-03-01

    These are the proceedings of a workshop on Distributed Digital Systems, Plant Process Computers, and Networks held in Charlotte, North Carolina on August 16--18, 1994. The purpose of the workshop was to provide a forum for technology transfer, technical information exchange, and education. The workshop was attended by more than 100 representatives of electric utilities, equipment manufacturers, engineering service organizations, and government agencies. The workshop consisted of three days of presentations, exhibitions, a panel discussion and attendee interactions. Original plant process computers at the nuclear power plants are becoming obsolete resulting in increasing difficulties in their effectiveness to support plant operations and maintenance. Some utilities have already replaced their plant process computers by more powerful modern computers while many other utilities intend to replace their aging plant process computers in the future. Information on recent and planned implementations are presented. Choosing an appropriate communications and computing network architecture facilitates integrating new systems and provides functional modularity for both hardware and software. Control room improvements such as CRT-based distributed monitoring and control, as well as digital decision and diagnostic aids, can improve plant operations. Commercially available digital products connected to the plant communications system are now readily available to provide distributed processing where needed. Plant operations, maintenance activities, and engineering analyses can be supported in a cost-effective manner. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  3. Seguidor solar adaptativo basado en un controlador lógico programable para paneles fotovoltaicos

    Directory of Open Access Journals (Sweden)

    Celso de la Cruz Casaño

    2012-12-01

    Full Text Available Objetivos: Desarrollar un sistema de seguimiento solar adaptativo para paneles solares fotovoltaicos que no necesitan una configuración inicial. Métodos: Se utilizó el método estructuralista, en el cual se observa la realidad, se construye modelos y se analiza la estructura. Se utilizaron bloques de programación del controlador lógico programable (PLC y de modelos de mecanismos para construir el modelo del seguidor solar; además se aplicó teorías de ingeniería de control como la estabilidad de sistemas dinámicos y control adaptativo. La prueba de estabilidad y el funcionamiento correcto se analiza utilizando todo el sistema en conjunto, luego, se validan estos análisis con las simulaciones y experimentaciones. Resultados: Se presentan resultados de simulación y experimentación, en los cuales se hace evidente que el controlador adaptativo mantiene el error de control de seguimiento muy bajo a pesar de las condiciones nubladas. En las simulaciones y experimentaciones no se requirió una configuración inicial; este hecho es uno de los requisitos que se busca alcanzar en los objetivos. La ventaja de la adaptación es que el seguidor solar seguirá la trayectoria del sol aun cuando este se encuentre oculto por las nubes. Conclusiones: El aporte fue brindar un diseño novedoso de un seguidor solar cronológico adaptativo. El algoritmo de control adaptativo evita la configuración inicial del seguidor solar cronológico.

  4. Investigation on the use digital controls instead of PID analog controls in the level control of steam generators of nuclear power PWR; Investigacao sobre o uso de controladores digitais em substituicao aos controladores analogicos PID para o controle de nivel de geradores de vapor de centrais nucleares PWR

    Energy Technology Data Exchange (ETDEWEB)

    Alvarenga, Marco Antonio Bayout

    2012-07-01

    The aim of this study is to identify current alternatives for the implementation of digital controllers in the level control of steam generators of nuclear power PWR (Pressurized Water Reaetor). It is intended to identify the types of digital controls that are available from the theoretical and conceptual viewpoints for this purpose. We investigate the advantages and disadvantages of each controller model. From this assessment are pointed the most suitable models in hierarchical scale. This evaluation also serves to suggest possible types of control installation as a whole, where the level control of the steam generators becomes just one of many controls that are part of the plant. In this case, the use of digital controls allows the non-linear and multivariable treatment which is characteristic of complex systems, such as the nuclear power generation. The treatment of nonlinearities and multivariable aspects allows a more detailed study of the stability of these plants when they are subject to transients or several accidents, such as the case of losing external power of transients. In the specific case of steam generators, the instabilities result from the emergence of the shrink and swell phenomenas, depending on the load variations of thermonuclear plant. The application of several types and digital controllers, considering these inherent characteristics of the level control of steam generators, allows to infer which types of controllers are more appropriate to treat instabilities of this type and to make conjectures in its use for the cases of more complex instabilities, considering the integration of all nucleus-plant controls.

  5. Controlador Predictivo No Lineal para la Gestión Energética del Sistema Centralizado de Aire Acondicionado de un Inmueble Hotelero

    Directory of Open Access Journals (Sweden)

    Adriana Acosta

    2015-10-01

    Full Text Available Resumen: En este trabajo se reflejan los resultados obtenidos durante la sintonía de un controlador predictivo basado en modelo no lineal, para la gestión energética del sistema centralizado de climatización de una instalación hotelera. Con el objetivo de lograr eficiencia económica, el diseño del controlador emplea un modelo de predicción del comportamiento del consumo energético de las habitaciones a partir de los registros históricos del hotel. La predicción de la carga térmica de las habitaciones se calcula utilizando el método de series de tiempo radiantes (RTS. La sintonía y simulación del controlador fue realizada con MATLAB®. Abstract: In this work we show the results obtained from the tuning of a non-linear model based predictive controller, for the energy management of an air conditioning centralized system in a hotel installation. With the aim of reaching economic efficiency, the controller design employs a prediction model of the energy consumption behaviour of the rooms based on the historic data of the hotel. Prediction of the thermal load of the rooms is obtained using the Radiant Time Series (RTS method. The application was developed in Matlab® programming language. Palabras clave: Control predictivo basado en modelo, método RTS, carga térmica, consumo eléctrico, hotel, Keywords: Model based predictive control, RTS method, thermal load, electrical consumption, hotel.

  6. Controlador borroso en un ondulador trifásico

    Directory of Open Access Journals (Sweden)

    Agustín Garzón Carbonell

    2011-02-01

    Full Text Available Se presenta la implementación de un controlador borroso diseñado para obtener un voltaje de salida de magnitudy frecuencia constantes, mediante un ondulador trifásico. Se plantea el diseño de los esquemas de potencia ycontrol. Es tratada igualmente la determinación de los valores de ciertos parámetros que se usarán para comprobarel funcionamiento del sistema: frecuencia de muestreo, conmutación, filtro de salida, para realizar experimentos.Se muestran y analizan los resultados obtenidos en las simulaciones para  cargas resistiva e inductiva.  The implementation of a fuzzy controller is presented, designed in order to obtaining a voltage of constant valueand fixed frequency, by means of a tree-phase inverter. The design of the power and control parts is shown,before detailing the characteristics of the architecture of the chosen inverter target of the control. The determina-tion of the values of certain parameters will be used to check the operation of the system is treated equally:sampling frequency, commutation, out filter, to carry out experiments.  They are shown and analyzed the resultsobtained in the simulations for R and L loads.

  7. Advanced digital technology - improving nuclear power plant performance through maintainability

    International Nuclear Information System (INIS)

    Ford, J.L.; Senechal, R.R.; Altenhein, G.D.; Harvey, R.P.

    1998-01-01

    In today's energy sector there is ever increasing pressure on utilities to operate power plants at high capacity factors. To ensure nuclear power is competitive into the next century, it is imperative that strategic design improvements be made to enhance the performance of nuclear power plants. There are a number of factors that affect a nuclear power plant's performance; lifetime maintenance is one of the major contributors. The maturing of digital technology has afforded ABB the opportunity to make significant design improvements in the area of maintainability. In keeping with ABB's evolutionary advanced nuclear plant design approach, digital technology has systematically been incorporated into the control and protection systems of the most recent Korean nuclear units in operation and under construction. One example of this was the multi-functional design team approach that was utilized for the development of ABB's Digital Plant Protection System (DPPS). The design team consisted of engineers, maintenance technicians, procurement specialists and manufacturing personnel in order to provide a complete perspective on all facets of the design. The governing design goals of increased reliability and safety, simplicity of design, use of off-the-shelf products and reduced need for periodic surveillance testing were met with the selection of proven ABB-Advant Programmable Logic Controllers (PLCs) as the heart of the DPPS. The application of digital PLC technology allows operation for extended periods without requiring routine maintenance or re-calibration. A well documented commercial dedication program approved by the United States Nuclear Regulatory Commission (US NRC) as part of the System 80+ TM Advanced Light Water Reactor Design Certification Program, allowed the use of off-the shelf products in the design of the safety protection system. In addition, a number of mechanical and electrical improvements were made which support maintainability. The result is a DPPS

  8. Use of digital photography for power plant retrofits

    International Nuclear Information System (INIS)

    Kamba, J.J.

    1995-01-01

    One of the latest advancements in electronic tools for reducing engineering and drafting effort is the use of digital photography (DP) for retrofit and betterment projects at fossil and nuclear power plants. Sargent and Lundy (S and L) has effectively used digital photography for condition assessments, minor backfit repairs, thermo-lag fire wrap assessments and repairs, and other applications. Digital photography offers several benefits on these types of projects including eliminating the need for official repair drawings and providing station maintenance with a true 3-D visualization of the repair

  9. Software V ampersand V methods for digital plant protection system

    International Nuclear Information System (INIS)

    Kim, Hung-Jun; Han, Jai-Bok; Chun, Chong-Son; Kim, Sung; Kim, Kern-Joong.

    1997-01-01

    Careful thought must be given to software design in the development of digital based systems that play a critical role in the successful operation of nuclear power plants. To evaluate the software verification and validation methods as well as to verify its system performance capabilities for the upgrade instrumentation and control system in the Korean future nuclear power plants, the prototype Digital Plant, Protection System (DPPS) based on the Programmable Logic Controller (PLC) has been constructed. The system design description and features are briefly presented, and the software design and software verification and validation methods are focused. 6 refs., 2 figs

  10. Development and application of integrated digital I and C system in Japanese PWR plants

    International Nuclear Information System (INIS)

    Tominaga, M.

    1995-01-01

    The Integrated Digital Instrumentation and Control (I and C) System has been developed and applied to non-safety grade I and C systems in the latest 5 Japanese PWR plants in 1990's. Based on the experience in these plants, the Integrated Digital I and C System will be planned to apply also to safety grade I and C systems in Advanced PWR (APWR) as the overall application of digital technology. The basic design task has been just started for APWR which is to be in commercial operation in early 2000's and under the development about various issues of safety grade digital I and C systems. On the other hand, in conventional Japanese PWR plants, digital I and C systems have been applied step by step since 1980's. For example, digital I and C systems for radio-active waste processing system have been adopted to 13 units, and dedicated digital I and C systems for Local loop control system to 8 units. The trend and status of development and application of the digital I and C systems, especially the Integrated Digital I and C System in Japanese PWR plants are presented. (5 refs., 4 figs.)

  11. Digital I and C system pre-tests using plant specific simulators

    International Nuclear Information System (INIS)

    Holl, B.; Probst, H.; Wischert, W.

    2006-01-01

    The paper focuses on strategic aspects of the implementation of modern digital instrumentation and control system (I and C) in nuclear power plant (NPP) training simulators and points out the way to identify the most appropriate implementation method of the digital I and C system in the simulator development environment which fulfils the requirement imposed by the nuclear power plants. This regards mainly training aspects, simulator as a test bed for design verification and validation (V and V), and software maintenance aspects with respect to future evolutions of the digital I and C system. (author)

  12. PI fussy multimodal controller of programmed gains for the operation in the wide range of a turbo gas unit; Controlador PI difuso multimodo de ganancias programadas para la operacion en rango amplio de una unidad turbogas

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Martinez, Arnulfo A.

    2004-11-15

    las tecnicas de control multimodo, control de ganancias programadas y logica difusa, con la finalidad de tener un sistema de control que proporcione un mejor desempeno en el control de velocidad y control de potencia de las unidades turbogas (UTGs), comparado con los sistemas de control actuales, las cuales estan basadas en algoritmos de control PI convencional. Con este nuevo algoritmo se busca tener un sistema de control de mejor calidad, que proporcione una buena respuesta de rechazo a perturbaciones asi como un buen seguimiento a la referencia. Los problemas que se tienen en la implementacion de la logica de conmutacion (control multimodo) y la estrategia de interpolacion (ganancias programadas) se resuelven aplicando controladores difusos los cuales mantienen las ventajas de ambas estrategias para el control de procesos no lineales en amplias regiones de operacion. Debido a que los controladores implementados por las reglas del sistema difuso son del mismo tipo (PI, Proporcional Integral), el diseno del controlador difuso multimodo de ganancias programadas se redujo al diseno de un controlador PI difuso de ganancias programadas (PI-DGP). Con la finalidad de definir el esquema de programacion de ganancias, se analizaron tres enfoques bien conocidos para el diseno de controladores difusos de ganancias programadas y se compararon los mecanismos de interpolacion de cada uno de ellos. La integracion de la estructura de un controlador PI generalizado en los controladores locales que conforman el controlador PI-DGP (ver capitulo 4), permitio generar una mejor accion de control tanto de rechazo a perturbaciones como de seguimiento a la referencia. Como producto final se obtuvo un controlador PI-DGP, el cual permitio obtener una estrategia de control mucho mas eficaz y mostro ser una solucion viable al problema tecnico planteado. Con el controlador PI-DGP se mejoro considerablemente el desempeno del control de velocidad de la UTG durante la etapa de arranque, asi como el

  13. Reliability Analysis Study of Digital Reactor Protection System in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Guo, Xiao Ming; Liu, Tao; Tong, Jie Juan; Zhao, Jun

    2011-01-01

    The Digital I and C systems are believed to improve a plants safety and reliability generally. The reliability analysis of digital I and C system has become one research hotspot. Traditional fault tree method is one of means to quantify the digital I and C system reliability. Review of advanced nuclear power plant AP1000 digital protection system evaluation makes clear both the fault tree application and analysis process to the digital system reliability. One typical digital protection system special for advanced reactor has been developed, which reliability evaluation is necessary for design demonstration. The typical digital protection system construction is introduced in the paper, and the process of FMEA and fault tree application to the digital protection system reliability evaluation are described. Reliability data and bypass logic modeling are two points giving special attention in the paper. Because the factors about time sequence and feedback not exist in reactor protection system obviously, the dynamic feature of digital system is not discussed

  14. EPRI training to support digital upgrades in nuclear plants

    International Nuclear Information System (INIS)

    Torok, R.; Naser, J.

    2006-01-01

    In response to the growing challenges of obsolescence and rising maintenance costs, utilities are increasingly upgrading or replacing their existing instrumentation and control (I and C) systems and components. In most cases, this involves analog-to-digital or digital-to-newer-digital replacements. However, the use of digital technology often raises new technical and licensing issues, particularly for safety-related applications. Examples include: new failure modes and the potential for common-mode failure of redundant components; electromagnetic compatibility (EMC); potential human-system interface problems; and software verification, validation, and configuration management. Successful implementation, operation and maintenance of digital systems depend to a great extent on having processes in place that are tailored for digital technology. Nuclear plants are therefore updating their processes as they start the migration to digital I and C. For several years, EPRI has been developing guidelines to address the key technical issues and interfacing with the U.S. NRC to ensure the acceptability of the approaches developed. A framework for implementing digital upgrades now exists, but practical experience under the current regulatory environment is sparse. Significant uncertainty exists in regard to both technical and licensing issues. Many utilities still need to prepare their staff and processes to properly handle the new technology. In recent years, this need has been exacerbated by staff reductions, changing job assignments, and declining training budgets. EPRI has responded by developing a training program to help utilities efficiently bring design and licensing engineers up to speed on the latest issues and guidance affecting the implementation of digital upgrades in nuclear plants. This paper describes the key technical issues in the context of the EPRI training program. (authors)

  15. Digital bus technology in new coal-fired plants

    Energy Technology Data Exchange (ETDEWEB)

    Blaney, J.; Murray, J. [Emerson Process Management (United States)

    2007-10-15

    The main issues associated with including digital bus technology such as Foundation fieldbus, Profibus-DP or DeviceNet, in a coal-fired power plant are deciding which systems to install and determining how to implement it. Although still new, digital bus experiences to date have shown that the technology performs solidly and when wiring best practices are followed a significantly shorted commissioning cycle can be achieved. 1 fig., 2 tabs.

  16. Cardinal principle and application practice of 3D digital model design for nuclear power plant

    International Nuclear Information System (INIS)

    Wang Ruobing; Wu Yan

    2005-01-01

    The practical application of 3D digital model design at nuclear power plants was introduced in detail in the paper. The whole process for system choice, program constitution, model design and project practice were also summarized. By demonstrating the cardinal principal and application practice of 3D digital model design as an important sub-project of CGNPC Digital Plant, the paper validates the rationality and validity of the major architecture system and program configuration of the digital plant, carries out beneficial attempt and study in the overall power plant life engineering management and site practice, and has achieved significant engineering and social benefits. The success of practices in the project accelerates the extended and extensive application of Digital Plant in the operation and maintenance simulation of Daya Bay and Ling'ao Nuclear Power Plants, and the engineering design management for Ling'ao II and III of CGNPC on a consolidated basis. (authors)

  17. Evaluation of fault coverage for digitalized system in nuclear power plants using VHDL

    International Nuclear Information System (INIS)

    Kim, Suk Joon; Lee, Jun Suk; Seong, Poong Hyun

    2003-01-01

    Fault coverage of digital systems is found to be one of the most important factors in the safety analysis of nuclear power plants. Several axiomatic models for the estimation of fault coverage of digital systems have been proposed, but to apply those axiomatic models to real digital systems, parameters that the axiomatic models require should be approximated using analytic methods, empirical methods or expert opinions. In this paper, we apply the fault injection method to VHDL computer simulation model of a real digital system which provides the protection function to nuclear power plants, for the approximation of fault detection coverage of the digital system. As a result, the fault detection coverage of the digital system could be obtained

  18. Digital I and C for nuclear power plant

    International Nuclear Information System (INIS)

    Gemst, P. van

    1993-01-01

    A summary is given of the past experience (process I and C, digital controllers, Power Range Monitoring system) and future plans (integrated plant I and C, control room) of ABB Atom for programmable I and C at nuclear power plants. ABB Atom has designed and supplied an appreciable quantity of software based equipment for nuclear power plants. These have been supplied for both new plants as well as for backfitting. The well proven ABB Master system has been used for the supply of I and C equipment for these projects and will continue to be used in the future. (Z.S.) 1 fig

  19. Algoritmos Evolutivos y su empleo en el ajuste de controladores del tipo PID: Estado Actual y Perspectivas

    Directory of Open Access Journals (Sweden)

    Gilberto Reynoso-Meza

    2013-07-01

    Full Text Available Resumen: Los controladores PID continúan siendo una solución fiable, robusta, práctica y sencilla para el control de procesos. Actualmente constituyen la primera capa de control de la gran mayoría de las aplicaciones industriales. De ahí que un número importante de trabajos de investigación se han orientado a mejorar su rendimiento y prestaciones. Las líneas de investigación en este campo van desde nuevos métodos de ajuste, pasando por nuevos tipos de estructura hasta metodologías de diseño integrales. Particularizando en el ajuste de parámetros, una de las formas de obtener una solución novedosa consiste en plantear un problema de optimización, el cual puede llegar a ser no-lineal, no-convexo y con restricciones. Dado que los algoritmos evolutivos han mostrado un buen desempeño para solucionar problemas complejos de optimización, han sido utilizados en diversas propuestas relacionadas con el ajuste de controladores PID. Este trabajo muestra un revisión de estas propuestas y las prestaciones obtenidas en cada caso. Así mismo, se identifican algunas tendencias y posibles líneas de trabajo futuras. Abstract: PID controllers are a reliable, robust, practical and easy to implement control solution for industrial processes. They provide the first control layer for a vast majority of industrial applications. Owing to this, several researches invest time and resources to improve their performance. The research lines in this field scope with new tuning methods, new types of structures and integral design methods. For tuning methods, improvements could be fulfilled stating an optimization problem, which could be non-linear, non-convex and highly constrained. In such instances, evolutionary algorithms have shown a good performance and have been used in various proposals related with PID controllers tuning. This work shows a review of these proposals and the benefits obtained in each case. Some

  20. Experience with digital instrumentation and control systems for CANDU power plant modifications

    International Nuclear Information System (INIS)

    Basu, S.

    1997-01-01

    Over the last years, Ontario Hydro CANDU power plants have gone through many modifications. This includes modification from analog hardwired controls to digital and solid state controls and replacement of the existing digital controls with the latest hardware and software technology. Examples of digital modifications at Bruce A and other CANDU power plants are briefly described and categorized. Most of the I and C technology development has been supported by the CANDU Owners Group (COG) a consortium of Canadian nuclear utilities and the Atomic Energy Canada Limited (AECL). (author)

  1. Experience with digital instrumentation and control systems for CANDU power plant modifications

    Energy Technology Data Exchange (ETDEWEB)

    Basu, S [Ontario Hydro, Toronto, ON (Canada)

    1997-07-01

    Over the last years, Ontario Hydro CANDU power plants have gone through many modifications. This includes modification from analog hardwired controls to digital and solid state controls and replacement of the existing digital controls with the latest hardware and software technology. Examples of digital modifications at Bruce A and other CANDU power plants are briefly described and categorized. Most of the I and C technology development has been supported by the CANDU Owners Group (COG) a consortium of Canadian nuclear utilities and the Atomic Energy Canada Limited (AECL). (author).

  2. Análise de controladores eletrônicos em sistemas de distribuição de energia

    OpenAIRE

    Alampi Filho, Sergio [UNESP

    2005-01-01

    O número crescente de cargas não-lineares, bem como altas taxas de energia pagas pelos consumidores, com tributações adicionais, tais como multas por baixo ou alto fator de potência, tarifas elevadas em horários de ponta e necessidade de elevados contratos de demanda, para suprir possíveis ultrapassagens de contrato, estão entre as principais motivações técnicas para a realização desta pesquisa. Sob esta perspectiva, os principais controladores FACTS são apresentados, com enfoque principal no...

  3. Servidor web empotrado en un FPGA para configurar un Controlador Maestro del Sistema Inteligente de Tráfico Cubano

    OpenAIRE

    Ríos Pérez, Frank Emilio; Polanco Carrillo, Franky; Moreno Vega, Valery

    2017-01-01

    RESUMEN En este artículo se presenta la implementación de un servidor web para configurar el Controlador Maestro del Sistema Inteligente de Tráfico desarrollado en Cuba. La programación del servidor se realizó en lenguaje C, para ejecutarse sobre un sistema operativo Linux empotrado en un FPGA. Se logró un mecanismo de configuración sencillo, de bajos recursos de cómputo, rápido y flexible.

  4. Some aspects of programmable digital systems usage in nuclear power plants

    International Nuclear Information System (INIS)

    Mandic, D.; Smolej, M.; Sucic, B.

    2004-01-01

    During the operation of the NPP Krsko - NEK and other nuclear power plants, it has been recognized that certain issues related to the usage of digital equipment and associated software in NPP technological process protection, control and monitoring, are usually not adequately addressed in the existing programs and procedures. Moreover, often the problems related to the programmable digital systems usage are not understood correctly, which means that they can not be treated properly. Owing to the specifics of the programmable digital systems usage they have to be treated in a different way than other plant equipment and related documentation. The term as well as the process of Process Computers Configuration Control was introduced to control, among other issues, three 10CFR50 Appendix B quality requirements related to the Process Computers application in NPP: Design Control, Document Control, Identification and Control of Materials, Parts and Components. Based on the experience from NEK and published experience from other NPP and other organizations, this paper sheds light on specifics of the programmable digital systems usage in nuclear power plants. The wording Programmable Digital Systems was used rather than Process Computers, to emphasize wide area of applicability of this term: from simple digital components with burned-in programs to the PLC (Programmable Logic Controllers) and large process computer systems. In order to satisfy requirements of the Process Computer Configuration Control, specific characteristics and specific problems related to the usage of programmable digital systems require specific treatment of these issues. This paper describes those specific characteristics and traditional misunderstandings, false beliefs, false expectations and common errors that are most frequently committed in the life cycle of the programmable digital systems, as well as consequences and problems that could develop. The paper also refers to the regulations, industry

  5. Application of digital field photographs as documents for tropical plant inventory.

    Science.gov (United States)

    LaFrankie, James V; Chua, Anna I

    2015-05-01

    We tested the credibility and significance of digital field photographs as supplements or substitutes for conventional herbarium specimens with particular relevance to exploration of the tropics. We made 113 collections in triplicate at a species-rich mountain in the Philippines while we took 1238 digital photographs of the same plants. We then identified the plants from the photographs alone, categorized the confidence of the identification and the reason for failure to identify, and compared the results to identifications based on the dried specimens. We identified 72.6% of the photographic sets with high confidence and 27.4% with low confidence or only to genus. In no case was a confident identification altered by subsequent examination of the dried specimen. The failure to identify photographic sets to species was due to the lack of a key feature in 67.8% of the cases and due to a poorly understood taxonomy in 32.2%. We conclude that digital photographs cannot replace traditional herbarium specimens as the primary elements that document tropical plant diversity. However, photographs represent a new and important artifact that aids an expedient survey of tropical plant diversity while encouraging broad public participation.

  6. Diseño de controladores P, PI y PID para el comportamiento dinámico de un servo-sistema hidráulico, basado en desarrollo experimental

    Directory of Open Access Journals (Sweden)

    María Elena Anaya Pérez

    2014-06-01

    Full Text Available Este artículo presenta el diseño de controladores Proporcional (P, Proporcional Integral (PI y Proporcional Integral Derivativo (PID, utilizando modelado matemático, simulación e implementación electrónica del comportamiento dinámico de un servo-sistema hidráulico, a través de la aplicación de la técnica de sintonización de Ziegler – Nichols basada en una metodología experimental para distintos puntos de operación. En la parte experimental de este trabajo son usados instrumentos de medición como data logger; la simulación del sistema se lleva a cabo en la plataforma de Matlab®. Además, el software ADAMView® es utilizado en el diseño de tres tipos de controladores: P, PI y PID, aplicados a diferentes puntos de operación de la planta.

  7. A development of digital plant protection system architecture

    International Nuclear Information System (INIS)

    Seong, S. H.; Park, H. Y.; Kim, D. H.; Seo, Y. S.; Gu, I. S.

    2000-01-01

    The digital plant protection system (DPPS) which have a large number of advantages compared to current analog protection system has been developed in various field. The major disadvantages of digital system are, however, vulnerable to faults of processor and software. To overcome the disadvantages, the concept of segment and partition in a channel has been developed. Each segment in a channel is divided from sensor to reactor trip and engineered safety features, which is based on the functional diversity of input signals against the various plant transient phenomena. Each partition allocates the function module to an independent processing module in order to process and isolate the faults of each module of a segment. A communication system based on the deterministic protocol with the predictable and hard real-time characteristics has been developed in order to link the various modules within a segment. The self-diagnostics including online test and periodic test procedures are developed in order to increase the safety, reliability and availability of DPPS. The developed DPPS uses the off-the-shelf DSP (digital signal processor) and adopts VME bus architecture, which have sufficient operation experience in the industry. The verification and validation and quality assurance of software has been developed and the architecture and protocol of deterministic communication system has been researched

  8. Digitization and Visualization of Greenhouse Tomato Plants in Indoor Environments

    Directory of Open Access Journals (Sweden)

    Dawei Li

    2015-02-01

    Full Text Available This paper is concerned with the digitization and visualization of potted greenhouse tomato plants in indoor environments. For the digitization, an inexpensive and efficient commercial stereo sensor—a Microsoft Kinect—is used to separate visual information about tomato plants from background. Based on the Kinect, a 4-step approach that can automatically detect and segment stems of tomato plants is proposed, including acquisition and preprocessing of image data, detection of stem segments, removing false detections and automatic segmentation of stem segments. Correctly segmented texture samples including stems and leaves are then stored in a texture database for further usage. Two types of tomato plants—the cherry tomato variety and the ordinary variety are studied in this paper. The stem detection accuracy (under a simulated greenhouse environment for the cherry tomato variety is 98.4% at a true positive rate of 78.0%, whereas the detection accuracy for the ordinary variety is 94.5% at a true positive of 72.5%. In visualization, we combine L-system theory and digitized tomato organ texture data to build realistic 3D virtual tomato plant models that are capable of exhibiting various structures and poses in real time. In particular, we also simulate the growth process on virtual tomato plants by exerting controls on two L-systems via parameters concerning the age and the form of lateral branches. This research may provide useful visual cues for improving intelligent greenhouse control systems and meanwhile may facilitate research on artificial organisms.

  9. Analysis of several digital network technologies for hard real-time communications in nuclear plant

    International Nuclear Information System (INIS)

    Song, Ki Sang; No, Hee Chun

    1999-01-01

    Applying digital network technology for advanced nuclear plant requires deterministic communication for tight safety requirements, timely and reliable data delivery for operation critical and mission-critical characteristics of nuclear plant. Communication protocols, such as IEEE 802/4 Tiken Bus, IEEE 802/5 Token Ring, FDDI, and ARCnet, which have deterministic communication capability are partially applied to several nuclear power plants. Although digital communication technologies have many advantages, it is necessary to consider the noise immunity form electromagnetic interference (EMI), electrical interference, impulse noise, and heat noise before selecting specific digital network technology for nuclear plant. In this paper, we consider the token frame loss and data frame loss rate due to the link error event, frame size, and link data rate in different protocols, and evaluate the possibility of failure to meet the hard real-time requirement in nuclear plant. (author). 11 refs., 3 figs., 4 tabs

  10. Practical Maintenance of Digital Systems: Guidance to Maximize the Benefits of Digital Technology for the Maintenance of Digital Systems and Plant Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D; Scarola, K

    2004-10-30

    This report presents detailed guidance for the maintenance and testing of modern digital systems. The guidance provides practical means for plants to take advantage of the increased diagnostic and self-test capabilities of these systems. It helps plants avoid mistakes in design and installation that could lead to increased maintenance burden and decreased system reliability and availability.

  11. Practical Maintenance of Digital Systems. Guidance to Maximize the Benefits of Digital Technology for the Maintenance of Digital Systems and Plant Equipment

    International Nuclear Information System (INIS)

    Hill, D.; Scarola, K.

    2004-01-01

    This report presents detailed guidance for the maintenance and testing of modern digital systems. The guidance provides practical means for plants to take advantage of the increased diagnostic and self-test capabilities of these systems. It helps plants avoid mistakes in design and installation that could lead to increased maintenance burden and decreased system reliability and availability

  12. Application of fault tree methodology to modeling of the AP1000 plant digital reactor protection system

    International Nuclear Information System (INIS)

    Teolis, D.S.; Zarewczynski, S.A.; Detar, H.L.

    2012-01-01

    The reactor trip system (RTS) and engineered safety features actuation system (ESFAS) in nuclear power plants utilizes instrumentation and control (IC) to provide automatic protection against unsafe and improper reactor operation during steady-state and transient power operations. During normal operating conditions, various plant parameters are continuously monitored to assure that the plant is operating in a safe state. In response to deviations of these parameters from pre-determined set points, the protection system will initiate actions required to maintain the reactor in a safe state. These actions may include shutting down the reactor by opening the reactor trip breakers and actuation of safety equipment based on the situation. The RTS and ESFAS are represented in probabilistic risk assessments (PRAs) to reflect the impact of their contribution to core damage frequency (CDF). The reactor protection systems (RPS) in existing nuclear power plants are generally analog based and there is general consensus within the PRA community on fault tree modeling of these systems. In new plants, such as AP1000 plant, the RPS is based on digital technology. Digital systems are more complex combinations of hardware components and software. This combination of complex hardware and software can result in the presence of faults and failure modes unique to a digital RPS. The United States Nuclear Regulatory Commission (NRC) is currently performing research on the development of probabilistic models for digital systems for inclusion in PRAs; however, no consensus methodology exists at this time. Westinghouse is currently updating the AP1000 plant PRA to support initial operation of plants currently under construction in the United States. The digital RPS is modeled using fault tree methodology similar to that used for analog based systems. This paper presents high level descriptions of a typical analog based RPS and of the AP1000 plant digital RPS. Application of current fault

  13. Digital image processing for radiography in nuclear power plants

    International Nuclear Information System (INIS)

    Heidt, H.; Rose, P.; Raabe, P.; Daum, W.

    1985-01-01

    With the help of digital processing of radiographic images from reactor-components it is possible to increase the security and objectiveness of the evaluation. Several examples of image processing procedures (contrast enhancement, density profiles, shading correction, digital filtering, superposition of images etc.) show the advantages for the visualization and evaluation of radiographs. Digital image processing can reduce some of the restrictions of radiography in nuclear power plants. In addition a higher degree of automation can be cost-saving and increase the quality of radiographic evaluation. The aim of the work performed was to to improve the readability of radiographs for the human observer. The main problem is lack of contrast and the presence of disturbing structures like weld seams. Digital image processing of film radiographs starts with the digitization of the image. Conventional systems use TV-cameras or scanners and provide a dynamic range of 1.5. to 3 density units, which are digitized to 256 grey levels. For the enhancement process it is necessary that the grey level range covers the density range of the important regions of the presented film. On the other hand the grey level coverage should not be wider than necessary to minimize the width of digitization steps. Poor digitization makes flaws and cracks invisible and spoils all further image processing

  14. Implementing digital instrumentation and control systems in the modernization of nuclear power plants

    International Nuclear Information System (INIS)

    2009-01-01

    The IAEA encourages greater use of good engineering and management practices by Member States. In particular, it supports activities such as nuclear power plant (NPP) performance improvement, plant life management, training, power uprating, operational license renewal and the modernization of instrumentation and control (I and C) systems of NPPs in Member States. The subject of implementing digital I and C systems in nuclear power plants was suggested by the Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI) in 2003. It was then approved by the IAEA and included in the programmes for 2006-2008. As the current worldwide fleet of nuclear power plants continues ageing, the need for improvements to maintain or enhance plant safety and reliability is increasing. Upgrading NPP I and C systems is one of the possible approaches to achieving this improvement, and in many cases upgrades are a necessary activity for obsolescence management. I and C upgrades at operating plants require the use of digital I and C equipment. While modernizing I and C systems is a significant undertaking, it is an effective means to enhance plant safety and system functionality, manage obsolescence, and mitigate the increasing failure liability of ageing analog systems. Many of the planning and implementation tasks of a digital I and C upgrade project described here are also relevant to new plant design and construction since all equipment in new plants will be digital. This publication explains a process for planning and conducting an I and C modernization project. Numerous issues and areas requiring special consideration are identified, and recommendations on how to integrate the licensing authority into the process are made. To complement this report, a second publication is planned which will illustrate many of the aspects described here through experience based descriptions of I and C projects and lessons learned from those activities. It is upon these

  15. Advanced digital computers, controls, and automation technologies for power plants: Proceedings

    International Nuclear Information System (INIS)

    Bhatt, S.C.

    1992-08-01

    This document is a compilation of the papers that were presented at an EPRI workshop on Advances in Computers, Controls, and Automation Technologies for Power Plants. The workshop, sponsored by EPRI's Nuclear Power Division, took place February 1992. It was attended by 157 representatives from electric utilities, equipment manufacturers, engineering consulting organizations, universities, national laboratories, government agencies and international utilities. More than 40% of the attendees were from utilities representing the majority group. There were 30% attendees from equipment manufacturers and the engineering consulting organizations. The participants from government agencies, universities, and national laboratories were about 10% each. The workshop included a keynote address, 35 technical papers, and vendor's equipment demonstrations. The technical papers described the state-of-the-art in the areas of recent utility digital upgrades such as digital feedwater controllers, steam generator level controllers, integrated plant computer systems, computer aided diagnostics, automated testing and surveillance and other applications. A group of technical papers presented the ongoing B ampersand W PWR integrated plant control system prototype developments with the triple redundant advanced digital control system. Several international papers from France, Japan and U.K. presented their programs on advance power plant design and applications. Significant advances in the control and automation technologies such as adaptive controls, self-tuning methods, neural networks and expert systems were presented by developers, universities, and national laboratories. Individual papers are indexed separately

  16. FOOT ROT DISEASE IDENTIFICATION FOR VELLAIKODI VARIETY OF BETELVINE PLANTS USING DIGITAL IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    J. Vijayakumar

    2012-11-01

    Full Text Available Betelvine plants are infected variety of diseases in the complete plantation without any premature warning of the diseases. The aim of this paper is to detection of foot rot disease in the vellaikodi variety of betelvine plants using digital image processing techniques. The digital images of the uninfected or normal betelvine leaves and the digital images of the infected in foot rot diseased betelvine leaves at different stages are collected from different Betelvine plants using a high resolution digital camera and collected betelvine images are stored with JPEG format. The digital images of the betelvine leaves analyses are done using the image processing toolbox in MATLAB which gives the normal patterns of the digital images. Using RGB encoding process, the RGB components of the betelvine leaves are separated. The mean and median values for all sample leaves are computed and calculated values are stored in the system. The mean and median values of test leaves are computed and compared with the stored values. As the result of this comparison, it is identified whether test leaves are affected by foot rot disease or not. Finally this analysis helps to recognize the foot rot disease can be identified before it spreads to entire crop.

  17. Application of digital field photographs as documents for tropical plant inventory1

    Science.gov (United States)

    LaFrankie, James V.; Chua, Anna I.

    2015-01-01

    Premise of the study: We tested the credibility and significance of digital field photographs as supplements or substitutes for conventional herbarium specimens with particular relevance to exploration of the tropics. Methods: We made 113 collections in triplicate at a species-rich mountain in the Philippines while we took 1238 digital photographs of the same plants. We then identified the plants from the photographs alone, categorized the confidence of the identification and the reason for failure to identify, and compared the results to identifications based on the dried specimens. Results: We identified 72.6% of the photographic sets with high confidence and 27.4% with low confidence or only to genus. In no case was a confident identification altered by subsequent examination of the dried specimen. The failure to identify photographic sets to species was due to the lack of a key feature in 67.8% of the cases and due to a poorly understood taxonomy in 32.2%. Discussion: We conclude that digital photographs cannot replace traditional herbarium specimens as the primary elements that document tropical plant diversity. However, photographs represent a new and important artifact that aids an expedient survey of tropical plant diversity while encouraging broad public participation. PMID:25995976

  18. Recent digital control and protection retrofits in power plants

    International Nuclear Information System (INIS)

    Fournier, R.D.; Hammer, M.; Smith, J.E.

    1987-01-01

    Digital computers are now being retrofitted to all types of power plants, replacing analog equipment and solving problems such as equipment obsolescence and low reliability. Three diverse examples of retrofits are presented in this paper, representing trends in man/machine interface design at an oil-fired plant, protection system in pressurized heavy-water reactors, and control systems in light water reactors (LWRs). The examples have been chosen to illustrate diverse reasons for the retrofits and the benefits derived. The cases presented report retrofits at Northern States Power's Monticello boiling water reactor, New Brunswick Electric Power Commission's (NBEPC's) Point Lepreau Nuclear Generating Station, and finally NBEPC's oil-fired plant at Courtney Bay

  19. Resultados Del Benchmark de Diseño De Controladores Para el Cabeceo de un Helicóptero

    Directory of Open Access Journals (Sweden)

    Mario García-Sanz

    2007-10-01

    Full Text Available Resumen: El presente documento describe los resultados del benchmark de control del ángulo de cabeceo de un helicóptero de laboratorio, anunciado en RIAI Vol. 4, Num. 1, pp. 107–110, 2007, y RIAI Vol. 3, Num. 2, pp. 111–116, 2006, y propuesto como Premio The Mathworks al mejor diseño para el banco de pruebas “Ingeniería de control” 2007. Palabras clave: Diseño de controladores, benchmark, control de helicópteros

  20. Application of digital control systems in nuclear power plants

    International Nuclear Information System (INIS)

    Keiper, J.T.

    1993-01-01

    This paper describes a sampling of recent digital applications, both safety related and non-safety related, in four nuclear power plants and discusses a few of the unique application experiences. Each application accrues unique benefits, but also poses unique problems. A few of the benefits and problems are discussed

  1. An Overview of Risk Quantification Issues for Digitalized Nuclear Power Plants using a Static Fault Tree

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyun Gook; Kim, Man Cheol; Lee, Seung Jun; Lee, Ho Jung; Eom, Heung Seop; Chol, Jong Gyun; Jang, Seung Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-08-15

    Risk caused by safety-critical instrumentation and control (I and C) systems considerably affects overall plant risk. As digitalization of safety-critical systems in nuclear power plants progresses, a risk model of a digitalized safety system is required and must be included in a plant safety model in order to assess this risk effect on the plant. Unique features of a digital system cause some challenges in risk modeling. This article aims at providing an overview of the issues related to the development of a static fault-tree-based risk model. We categorize the complicated issues of digital system probabilistic risk assessment (PRA) into four groups based on their characteristics: hardware module issues, software issues, system issues, and safety function issues. Quantification of the effect of these issues dominates the quality of a developed risk model. Recent research activities for addressing various issues, such as the modeling framework of a software-based system, the software failure probability and the fault coverage of a self monitoring mechanism, are discussed. Although these issues are interrelated and affect each other, the categorized and systematic approach suggested here will provide a proper insight for analyzing risk from a digital system

  2. Safety Evaluation of Full Digital Plant Protection System of Shin-Kori 3 and 4 in Korea

    International Nuclear Information System (INIS)

    Koh, J. S.; Kim, D. I.; Jeong, C. H.; Park, H. S.; Ji, S. H.; Kang, Y. D.; Park, G. Y.

    2009-01-01

    Keeping pace with the emerging trend of digital computer technologies, KHNP has utilized full digital plant protection system into the design of I and C systems at SKN 3 and 4. This paper presents safety review activities and results related to digital plant protection systems during the licensing of construction permit for the Shin-Kori 3 and 4(SKN 3 and 4) in Korea. The major licensing issues regarding the digital systems were software quality and cyber security during planning stage, system integrity with fail-safe design, EMI equipment qualification of digital systems, FPGA qualification and communication independence between safety and non-safety System. This paper addresses our approach to evaluate full digital protection systems with revised safety review guidelines and the resulting discussion to resolve the licensing issues

  3. State-of-art report on digital I and C system reliability issues for nuclear power plants

    International Nuclear Information System (INIS)

    Hwang, In Koo; Lee, Dong Gyoung; Cha, Kyung Ho; Kwon, Kee Choon; Wood, Richard T.

    2000-01-01

    As the instrumentation and control (Iand C) equipment suppliers tend to provide digital components rather than conventional analog type components for instrument and control systems of nuclear power plants(NPPs), it is unavoidable to adopt digital equipment for safety I and C systems as well as non-safety systems. However, the full introduction of digital equipment to I and C systems of nuclear power plants raises several concerns which have not been considered for conventional analog I and C systems. The two major examples of the issues of digital systems are electromagnetic compatibility (EMC) and software reliability. KAERI invited a technical expert, Dr. Richard T. Wood, from Oak Ridge National Laboratory (ORNL) in Unites States and held seminars to recognize the state-of-art of the above issues and to share the information on techniques dealing with the problems. Dr. Wood has been working on the development of EMC guidelines and technical basis in using digital equipment for safety systems in nuclear power plants on the sponsorship of US Nuclear Regulatory Commission (NRC). Being based on his statements and discussions during his visit, this report describes technical considerations and issues on digital safety I and C system application in NPPs, EMC methods, environmental effects vulnerable to digital components, reliability assurance methods, etc. (author)

  4. Reliability study: digital engineered safety feature actuation system of Korean Standard Nuclear Power Plant

    International Nuclear Information System (INIS)

    Sudarno; Kang, H. G.; Jang, S. C.; Eom, H. S.; Ha, J. J.

    2003-04-01

    The usage of digital Instrumentation and Control (I and C) in a nuclear power plant becomes more extensive, including safety related systems. The PSA application of these new designs are very important in order to evaluate their reliability. In particular, Korean Standard Nuclear Power Plants (KSNPPs), typically Ulchin 5 and 6 (UCN 5 and 6) reactor units, adopted the digital safety-critical systems such as Digital Plant Protection System (DPPS) and Digital Engineered Safety Feature Actuation System (DESFAS). In this research, we developed fault tree models for assessing the unavailability of the DESFAS functions. We also performed an analysis of the quantification results. The unavailability results of different DESFAS functions showed that their values are comprised from 5.461E-5 to 3.14E-4. The system unavailability of DESFAS AFAS-1 is estimated as 5.461E-5, which is about 27% less than that of analog system if we consider the difference of human failure probability estimation between both analyses. The results of this study could be utilized in risk-effect analysis of KSNPP. We expect that the safety analysis result will contribute to design feedback

  5. Optimal sampling period of the digital control system for the nuclear power plant steam generator water level control

    International Nuclear Information System (INIS)

    Hur, Woo Sung; Seong, Poong Hyun

    1995-01-01

    A great effort has been made to improve the nuclear plant control system by use of digital technologies and a long term schedule for the control system upgrade has been prepared with an aim to implementation in the next generation nuclear plants. In case of digital control system, it is important to decide the sampling period for analysis and design of the system, because the performance and the stability of a digital control system depend on the value of the sampling period of the digital control system. There is, however, currently no systematic method used universally for determining the sampling period of the digital control system. Generally, a traditional way to select the sampling frequency is to use 20 to 30 times the bandwidth of the analog control system which has the same system configuration and parameters as the digital one. In this paper, a new method to select the sampling period is suggested which takes into account of the performance as well as the stability of the digital control system. By use of the Irving's model steam generator, the optimal sampling period of an assumptive digital control system for steam generator level control is estimated and is actually verified in the digital control simulation system for Kori-2 nuclear power plant steam generator level control. Consequently, we conclude the optimal sampling period of the digital control system for Kori-2 nuclear power plant steam generator level control is 1 second for all power ranges. 7 figs., 3 tabs., 8 refs. (Author)

  6. Controlador Borroso Multivariable para el Ajuste de Tratamientos en Agricultura de Precisión

    Directory of Open Access Journals (Sweden)

    Xavier P. Burgos-Artizzu

    2007-04-01

    Full Text Available Resumen: Se presenta un control borroso MIMO sobre una barra multisección de aplicación de tratamientos incorporada a un tractor, que controla la apertura y cierre de cada una de las secciones de la barra y la dosis de herbicida a aplicar en cada instante, actuando sobre el caudal de la barra y la velocidad del vehículo. La dosificación se determina a partir de los resultados suministrados por un sistema de procesamiento de imágenes que genera, para el campo a tratar, los mapas de distribución de mala hierba y estado de crecimiento de cultivo, a partir de un muestreo fotográfico. El controlador se ha desarrollado y simulado en Matlab con resultados muy satisfactorios que indican un ahorro significativo en la cantidad de herbicida a utilizar, manteniendo un alto nivel de eficacia en el tratamiento de las infestaciones. Palabras clave: Control Borroso, Control multivariable, Agricultura de Precisión, Conocimiento experto

  7. Digital Counts of Maize Plants by Unmanned Aerial Vehicles (UAVs

    Directory of Open Access Journals (Sweden)

    Friederike Gnädinger

    2017-05-01

    Full Text Available Precision phenotyping, especially the use of image analysis, allows researchers to gain information on plant properties and plant health. Aerial image detection with unmanned aerial vehicles (UAVs provides new opportunities in precision farming and precision phenotyping. Precision farming has created a critical need for spatial data on plant density. The plant number reflects not only the final field emergence but also allows a more precise assessment of the final yield parameters. The aim of this work is to advance UAV use and image analysis as a possible high-throughput phenotyping technique. In this study, four different maize cultivars were planted in plots with different seeding systems (in rows and equidistantly spaced and different nitrogen fertilization levels (applied at 50, 150 and 250 kg N/ha. The experimental field, encompassing 96 plots, was overflown at a 50-m height with an octocopter equipped with a 10-megapixel camera taking a picture every 5 s. Images were recorded between BBCH 13–15 (it is a scale to identify the phenological development stage of a plant which is here the 3- to 5-leaves development stage when the color of young leaves differs from older leaves. Close correlations up to R2 = 0.89 were found between in situ and image-based counted plants adapting a decorrelation stretch contrast enhancement procedure, which enhanced color differences in the images. On average, the error between visually and digitally counted plants was ≤5%. Ground cover, as determined by analyzing green pixels, ranged between 76% and 83% at these stages. However, the correlation between ground cover and digitally counted plants was very low. The presence of weeds and blurry effects on the images represent possible errors in counting plants. In conclusion, the final field emergence of maize can rapidly be assessed and allows more precise assessment of the final yield parameters. The use of UAVs and image processing has the potential to

  8. Regulatory perspective on digital instrumentation and control systems for future advanced nuclear power plants

    International Nuclear Information System (INIS)

    Chiramal, M.

    1993-01-01

    This paper deals with the question of using digital technology in instrumentation and control systems for modern nuclear power reactors. The general opinion in the industry and among NRC staff is that such technology provides the opportunity for enhanced safety and reliable reactor operations. The major concern is the safe application of this technology so as to avoid common mode or common cause failures in systems. There are great differences between digital and analog system components. SECY-91-292 identifies some general regulatory concerns with regard to digital systems. There is clearly a lack of adequate regulatory direction on the application of digital equipment at this time, but the issue is being addressed by the industry, outside experts, and NRC staff. NRC staff presents a position on the issue of defense-in-depth and diversity with regard to insuring plant safety. Independent manual controls and readouts must be available to allow safe shutdown and monitoring of the plant in the event of safety system failures

  9. Projeto de um controlador adaptativo para robôs manipuladores no espaço de juntas

    Directory of Open Access Journals (Sweden)

    Nardênio Almeida Martins

    2001-05-01

    Full Text Available Este artigo apresenta o projeto de um controlador adaptativo de robôs manipuladores no espaço de juntas. Uma nova lei de controle adaptativa composta, que usa o erro de predição e os erros de seguimento para direcionar a estimação de parâmetros, é baseada na passividade e no método direto de Lyapunov. A convergência e a estabilidade global são mostradas para o algoritmo de controle adaptativo. O algoritmo tem as vantagens de não necessitar da “medição” de aceleração nas juntas e de não necessitar que a inversa da matriz de inércia estimada seja limitada. Exemplos de simulação são fornecidos para demonstrar o desempenho do algoritmo proposto

  10. A maximum power point tracker for photovoltaic system using a PIC microcontroller; Controlador de potencia maxima para sistemas fotovoltaicos (SFVs) utilizando un microcontrolador PIC

    Energy Technology Data Exchange (ETDEWEB)

    Guzman, Eusebio; Mendoza, Victor X; Carrillo, Jose J . A; Galarza, Cristian [Universidad Autonoma Metropolitana, Mexico, D.F. (Mexico)

    2000-07-01

    A maximum power point tracker MPPT for photovoltaic systems is presented. The equipment can output up to 600 W and its control signals are generated by a PIC microcontroller. The principle of control is based on current and voltage sampling at the output terminals of the photovoltaic generator. From power comparison of two consecutive samples, it is possible to know how far from the optimal point the system is working. Output voltage control is used to force the system to work within the optimal area of operation. The microcontroller program sequence, the DC/DC converter structure and the most relevant results are shown. [Spanish] En este trabajo se presenta el desarrollo de un controlador de potencia maxima para su aplicacion en sistemas fotovoltaicos (SFVs). El diseno alcanza una potencia de 600 W y sus senales de control son generadas con un controlador PIC. El principio de control se basa en el muestreo de la corriente y la tension en las terminadas del generador fotovoltaico GFV. De dos muestreos consecutivos, y por comparacion de las potencias, se determina que tan alejado del punto optimo opera el sistema. La operacion del sistema dentro de la zona de funcionamiento optimo se asegura mediante un control por tension. Se muestra la secuencia de programacion del microcontrolador, la estructura del convertidor CD/CD empleado y algunos resultados relevantes.

  11. A Pipeline for 3D Digital Optical Phenotyping Plant Root System Architecture

    Science.gov (United States)

    Davis, T. W.; Shaw, N. M.; Schneider, D. J.; Shaff, J. E.; Larson, B. G.; Craft, E. J.; Liu, Z.; Kochian, L. V.; Piñeros, M. A.

    2017-12-01

    This work presents a new pipeline for digital optical phenotyping the root system architecture of agricultural crops. The pipeline begins with a 3D root-system imaging apparatus for hydroponically grown crop lines of interest. The apparatus acts as a self-containing dark room, which includes an imaging tank, motorized rotating bearing and digital camera. The pipeline continues with the Plant Root Imaging and Data Acquisition (PRIDA) software, which is responsible for image capturing and storage. Once root images have been captured, image post-processing is performed using the Plant Root Imaging Analysis (PRIA) command-line tool, which extracts root pixels from color images. Following the pre-processing binarization of digital root images, 3D trait characterization is performed using the next-generation RootReader3D software. RootReader3D measures global root system architecture traits, such as total root system volume and length, total number of roots, and maximum rooting depth and width. While designed to work together, the four stages of the phenotyping pipeline are modular and stand-alone, which provides flexibility and adaptability for various research endeavors.

  12. ANALISIS DE SENSIBILIDAD Y APLICACIÓN DE LA ESTRTEGIA DE CONTROL POR PROGRAMACION DE GANANCIAS BASADA EN CONTROLADORES PID AL MODELO DE REGULACION DE GLUCOSA

    Directory of Open Access Journals (Sweden)

    Oriana José Pérez Dávila

    2018-01-01

    Full Text Available La diabetes mellitus ha sido considerada como un grupo de alteraciones metabólicas caracterizada por hiperglucemias o hipoglucemias. Esta enfermedad aparece i cuando la cantidad de insulina que produce el páncreas no es suficiente para mantener las necesidades del organismo ii cuando la insulina no tiene efecto sobre el organismo o iii cuando el páncreas deja de funcionar y la producción de insulina desaparece. En este trabajo se propone un análisis de sensibilidad usando el modelo de regulación de glucosa para un sujeto sano. Este análisis consiste en la variación de los parámetros del modelo hasta obtener cambios en las condiciones basales del paciente. Se encontraron tres parámetros con alta sensibilidad los cuales permitieron generar una población de ocho pacientes con diferentes condiciones basales de glucosa e insulina. Debido que para las personas con diabetes es difícil mantener los valores de glucosa durante 24 horas, se propuso aplicar para esta población de pacientes una estrategia de control por programación de ganancias basada en controladores PID para mantener los niveles de glucosa estables. Tres zonas de operación del modelo fueron escogidas para la aplicación del controlador, una zona alta para valores de glucosa mayores a 120 mg/dl, una zona media para valores de glucosa comprendidos entre 100 a 120 mg/dl y una zona baja para valores de glucosa menores a 100 mg/dl. Como resultado se obtuvo que utilizando la estrategia de control propuesta se logra una mayor velocidad de respuesta y se logra mantener los valores de glucosa en sangre dentro de los rangos normales que cuando se usa un controlador PID sencillo, es decir, no se producen episodios de hipoglucemia o hiperglucemia. Usando la estrategia por programación de ganancias se tiene un mejor tiempo de asentamiento antes y después de las comidas sin producir valores de glicemia que puedan poner en riesgo la vida del paciente.

  13. Development of 3D VR plant digital information system

    International Nuclear Information System (INIS)

    Suh, Kune Y.; Ryu, Joong W.; Kang, Myung G.; Kim, H. Y.; Cho, J. G.; Kim, D. H.; Park, J. W.

    2006-07-01

    Currently, there are many ongoing efforts to shorten the plant refueling and maintenance outage durations, and it is expected to become more active as the time goes on. Improved training and education system are required for the personnel to perform efficient inspection on time. This work is focused on establishing virtual Nuclear Power Plant system which will help train the personnel to understand the system characteristics of the plant by creating navigation enabled 3D plant mockups. Furthermore, this project is aimed at constructing information management system over the whole plant area, by integrating safety related data and combining it with web based GUI technology, to make search and management activities easy. This project spans three years. The forst year was spent in 3D mockup modeling of most part of the plant, and prototyping the web based VR plant digital information system. Plant environment, buildings, reactor structure, steam generator, pressurizer, fuel assemblies, pressurizer safety valve, main steamline safety valve, reactor coolant system, main steamline system, auxiliary and main coolant supply system were modeled into 3D mockups. Control functions such as magnification, rotation, movement, transparency, location detection, cross-cut view, full screen toggle and screen capture were implemented to facilitate manipulation of and navigation through the VR mockups. It is expected that the VR plant will serve as an effective support system for power plant regulation and inspection

  14. Evaluation of mental workload on digital maintenance systems in nuclear power plants

    International Nuclear Information System (INIS)

    Hwang, S. L.; Huang, F. H.; Lin, J. C.; Liang, G. F.; Yenn, T. C.; Hsu, C. C.

    2006-01-01

    The purpose of this study is to evaluate operators' mental workload dealing with digital maintenance systems in Nuclear Power Plants. First of all, according to the factors affected the mental workload, a questionnaire was designed to evaluate the mental workload of maintenance operators at the second Nuclear Power (NPP) in Taiwan. Then, sixteen maintenance engineers of the Second NPP participated in the questionnaire survey. The results indicated that the mental workload was lower in digital systems than that in analog systems. Finally, a mental workload model based on Neural Network technique was developed to predict the workload of maintenance operators in digital maintenance systems. (authors)

  15. Technical Challenges in the Application and Licensing of Digital Instrumentation and Control Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    2015-01-01

    With the modernization of existing analogue instrumentation and control (I&C) systems in nuclear power plants through digital I&C technology, and the implementation of digital I&C systems in new plants, the industry is faced with significant challenges. These challenges appear in the form of difficulties in managing the necessarily incremental transition, highly integrated (and interdependent) architectures, the flexible configurability enabled by digital technology, and uncertainty and inconsistency in licensing digital I&C systems and equipment in the different Member States. This publication discusses 17 major issues that utilities, developers, suppliers and regulatory stakeholders need to consider, so that the industry can capture and benefit from shared experience, recent technological developments, and emerging best practices

  16. Digital nuclear instrumentation application to nuclear power plant

    International Nuclear Information System (INIS)

    Burel, J.-P.; Fanet, H.

    1993-01-01

    The use of digital techniques for the control of nuclear reactors offers an interesting prospect in the improvement of the operation and safety of reactors. Thanks to close collaboration between Merlin Gerin and the French Atomic Energy Commission, a new piece of technology for nuclear instrumentation systems has been developed in order to meet the needs of different types of reactors. The principles of measurement are presented and the technology used is described. Other interesting points of this technology in addition to installation, operation and safety are examined. The digital neutron measurements are already operating in research reactors in France and will be installed in a different configuration in the new 1400 MW nuclear power plant. Integration into different designs is easily attainable by adapting the information transmission mode according to the technology present in the protection system and the treatment and visualization systems. (author)

  17. Factibilidad del uso del almidón de achira como agente controlador de fltrado en lodos de perforación base agua

    Directory of Open Access Journals (Sweden)

    Emiliano Ariza León

    2013-06-01

    Full Text Available El almidón de achira es un polímero de glucosa natural proveniente de una variedad de plantas o semillas, compuesto principalmente por una fracción molecular lineal (amilosa y una ramificada (amilopectina, la relación de estos componentes y su organización física dentro de la estructura granular le confiere al almidón propiedades fisicoquímicas y funcionales características. La industria de los hidrocarburos desde el año de 1930, ha venido utilizando el almidón como agente aditivo en todo tipo de lodos, mostrando alta eficacia en funciones durante las actividades de perforación tales como la remoción de sólidos del fondo del hueco y en el control de filtrado hacia la formación. En este trabajo se evalúo la efectividad del almidón de achira o sagú sin modificar, como agente controlador de filtrado en lodos de perforación base agua, respecto a otros aditivos comercialmente utilizados por la industria, elaborados a base de celulosa polianiónica y polisacárido preservado. Se realizaron, al fluido de perforación y a condiciones de laboratorio, pruebas estándar de filtrado API, reología y pH.Los resultados de esta investigación muestran que el almidón de achira puede ser utilizado como agente controlador de filtrado en lodos de perforación base agua con un rendimiento superior comparado con los aditivos utilizados en este proyecto.

  18. Human Reliability analysis for digitized nuclear power plants: Case study on the LingAo II nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Yan Hua; Zhang, Li [Institute of Human Factors Engineering AND Safety Management, Hunan Institute of Technology, Hengyang (China); Dai, Cao; Li, Peng Cheng; Qing, Tao [Human Factors Institute, University of South China, Hengyang (China)

    2017-03-15

    The main control room (MCR) in advanced nuclear power plants (NPPs) has changed from analog to digital control system (DCS). Operation and control have become more automated, centralized, and accurate due to the digitalization of NPPs, which has improved the efficiency and security of the system. New issues associated with human reliability inevitably arise due to the adoption of new accident procedures and digitalization of main control rooms in NPPs. The LingAo II NPP is the first digital NPP in China to apply the state-oriented procedure. In order to address issues related to human reliability analysis for DCS and DCS + state-oriented procedure, the Hunan Institute of Technology conducted a research project based on a cooperative agreement with the LingDong Nuclear Power Co. Ltd. This paper is a brief introduction to the project.

  19. Human Reliability Analysis for Digitized Nuclear Power Plants: Case Study on the LingAo II Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Yanhua Zou

    2017-03-01

    Full Text Available The main control room (MCR in advanced nuclear power plants (NPPs has changed from analog to digital control system (DCS. Operation and control have become more automated, centralized, and accurate due to the digitalization of NPPs, which has improved the efficiency and security of the system. New issues associated with human reliability inevitably arise due to the adoption of new accident procedures and digitalization of main control rooms in NPPs. The LingAo II NPP is the first digital NPP in China to apply the state-oriented procedure. In order to address issues related to human reliability analysis for DCS and DCS + state-oriented procedure, the Hunan Institute of Technology conducted a research project based on a cooperative agreement with the LingDong Nuclear Power Co. Ltd. This paper is a brief introduction to the project.

  20. Herramienta para programar un controlador lógico programable basado en hardware reconfigurable

    Directory of Open Access Journals (Sweden)

    Valery Moreno Vega

    2011-09-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} El presente trabajo se basa en el desarrollo de una herramienta que permita programar un controlador lógico programable (PLC basado en hardware reconfigurable. El desarrollo de la aplicación está  sustentado por una de las metodologías ágiles descrita por XP, utilizando las técnicas de modelación establecidas por el Lenguaje Unificado de Modelado (UML y haciendo uso de una potente herramienta de programación y diseño de interfaces gráficas como es Qt. La programación del PLC se realiza mediante el lenguaje de escalera, atendiendo la norma IEC 61131-3.

  1. 3D digital dynamic management of maintenance projects for nuclear power plant

    International Nuclear Information System (INIS)

    Wang Baizhong; Luo Yalin; Fang Hao; Ma Li; Zhang Jie; Wang Ruobing; Xie Min

    2005-01-01

    The whole process for the application of digital plant technique in the equipment transport in reactor building and the dynamic management of the spatial arrangement in Daya Bay Nuclear Power Station was introduced in the paper. The establishment of 3D digital Daya Bay plant, and the method and procedure to apply it in the nuclear power plant maintenance project have been discussed. This project utilizes the outer database to preserve the maintenance status of equipments, and avoids the damage or changing of the original 3D final model. Based on the maintenance procedure, the spatial arrangement and schedule for the maintenance of nuclear power station have been simulated and optimized for the whole process. This technique can simulate and optimize the arrangement and spatial arrangement for maintenance in limited space. It has been applied successfully in the reactor vessel head replacement for Unit 2 of Daya Bay NPP to shorten the time for key routes and the total time of this project by 16 hours and 92.5 hours, respectively. (author)

  2. Digital Sensor Technology

    Energy Technology Data Exchange (ETDEWEB)

    Ted Quinn; Jerry Mauck; Richard Bockhorst; Ken Thomas

    2013-07-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy, reliability, availability, and maintainability. This report demonstrates these benefits in direct comparisons of digital and analog sensor applications. It also addresses the qualification issues that must be addressed in the application of digital sensor technology.

  3. Comparison of piping models for digital power plant simulators

    International Nuclear Information System (INIS)

    Sowers, G.W.

    1979-08-01

    Two piping models intended for use in a digital power plant simulator are compared. One is a finite difference approximation to the partial differential equation called PIPE, and the other is a function subroutine that acts as a delay operator called PDELAY. The two models are compared with respect to accuracy and execution time. In addition, the stability of the PIPE model is determined. The PDELAY model is found to execute faster than the PIPE model with comparable accuracy

  4. A digital simulation of a pressurizer in a PWR nuclear power plant

    International Nuclear Information System (INIS)

    Sato, E.F.

    1980-11-01

    A model for pressurizer digital simulation of a PWR nuclear power plant during transients, considering all pressurizer control features, is presented. The pressurizer is divided into two regions separated by a water-vapor interface and non-equilibrium conditions are considered. The particular thermodynamic process followed during insurge and outsurges is determined at each instant of analysis without any previous assumption. The pressure behavior is defined by an explicit equation in any of four possible pressurizer thermodynamic conditions. Thermodynamic properties of steam and water are computed by ASME subroutines and the mathematical formulation presented in this study was programed in FORTRAN IV for a Burroughs-6700 digital computer system. This program was employed to simulate the Shippingport Atomic Power Station and Almirante Alvaro Alberto Nuclear Power Plant - Unit 1 pressurizers. The test results compared with experimental or vendor data show the validity of this analysis method. (Author) [pt

  5. Insights from a reliability review of digital plant protection system

    International Nuclear Information System (INIS)

    Kim, I.S.; Hwang, S.W.; Kim, B.S.; Jeong, C.H.; Oh, S.H.

    2001-01-01

    The full text follows: As part of the design efforts for Ulchin nuclear power plant units 5 and 6 of Korea, a reliability analysis of digital plant protection system (DPPS) was performed by ABB-CE. An independent review of the DPPS reliability analysis was undertaken by Hanyang University to assist Korea Institute of Nuclear Safety (KINS), the nuclear regulatory body of Korea, in evaluating the design acceptability of the digital system. The DPPS is designed to encompass both reactor trip function and ESFAS (engineered safety feature actuation system) initiation function. The major methods used by the ABB-CE to assess the Ulchin 5-6 DPPS reliability are failure mode and effect analysis (FMEA) and fault tree analysis. Hence, our independent review was conducted focusing on: -) the establishment of review criteria based on various sources, such as the standard review plan of KINS, 10CFR50 Appendix A, IEEE standards 279, 577, and 603; -) the suitability of the FMEA and fault tree analysis for the Ulchin 5-6 DPPS, including the specific methods used (e.g., for human reliability analysis and common-cause failure analysis), the assumptions made (e.g., with respect to test frequency and watchdog timer coverage), and the data employed (e.g., CCF parameter, human error probability, and processor failure rate); and -) the design acceptability of the DPPS especially as compared to the analog plant protection system from a reliability and safety perspective. The paper shall also discuss key issues requiring further in-depth investigation, such as reliability of programmable logic controllers (PLCs), coverage factor of watchdog timers, and susceptibility of redundant digital units to common cause failure. Sensitivity analyses were carried out to investigate the impact of several parameters of special interest, like the coverage factor of watchdog timer and human error probability (e.g. an operator error to manually trip the reactor, or to mis-calibrate the trip parameters) on

  6. Effect Analysis of Digital I and C Systems on Plant Safety based on Fault-Tree Analysis

    International Nuclear Information System (INIS)

    Lee, Seung Jun; Jung, Wondea

    2014-01-01

    Deterioration and an inadequate supply of components of analog I and C systems have led to inefficient and costly maintenance. Moreover, since the fast evolution of digital technology has enabled more reliable functions to be designed for NPP safety, the transition from analog to digital has been accelerated. Owing to the distinguishable characteristics of digital I and C systems, a reliability analysis of digital systems has become an important element of a probabilistic safety assessment (PSA). Digital I and C systems have unique characteristics such as fault-tolerant techniques and software. However, these features have not been properly considered yet in most NPP PSA models. The effect of digital I and C systems should be evaluated by comparing them to that of analog I and C systems. Before installing a digital I and C system, even though it is expected that the plant safety can be improved through the advantageous features of digital I and C systems, it should be validated whether the total NPP safety is better than analog systems or is the same at least. In this work, the fault-tree (FT) technique, which is most widely used in a PSA, was used to compare the effects of analog and digital I and C systems. From a case study, the results of plant safety were compared. In this work, the effect of a digital RPS was evaluated by comparing it to that of an analog RPS based on the FT models. In the evaluation results, it was observed that digital RPS has a positive effect on reducing the system unavailability. The analysis results can be used for the development of a guide for evaluating digital I and C systems and reliability requirements

  7. Method for fault diagnosis of digital control systems in nuclear power plant

    International Nuclear Information System (INIS)

    Suzuki, Satoshi; Nagaoka, Yukio; Ohga, Yukiharu; Ito, Tetsuo

    1990-01-01

    This paper presents a method for localizing faulty components of control systems by replaceable parts such as print boards and cables, in a large scale plant like a nuclear power plant. Most of today's control systems form a distributed configuration including many digital controllers interconnected by data communication networks. Usually, to localize the faulty components in nuclear plant control systems, suspected faulty components are narrowed down by executing manual tests to examine whether the objects are normal or abnormal based on design documents and personnel know-how, besides the uses of self-diagnosis functions built into the control systems. In the present method, procedures of various tests including the know-how and checking of self-diagnosis functions are provided as knowledge of tests. The tests to be executed is determined by considering failure probabilities of objects, and easiness and effectiveness of testing. Then, the suspects are narrowed down sequentially based on the test result. In checking feasibility of this diagnosis method for a simulated control system, intended faults are satisfactorily localized. This method is confirmed to be practicable for diagnosis of large scale digital control systems. (author)

  8. Key Regulatory Issues for Digital Instrumentation and Control Systems at Nuclear Power Plants

    International Nuclear Information System (INIS)

    Korsah, Kofi; Wood, Richard Thomas

    2008-01-01

    To help reduce the uncertainty associated with application of digital instrumentation and controls (I and C) technology in nuclear power plants, the Nuclear Regulatory Commission (NRC) has issued six Interim Staff Guidance (ISG) documents that address the current regulatory positions on what are considered the significant digital I and C issues. These six documents address the following topics: Cyber Security, Diversity and Defense-in-Depth, Risk Informed Digital I and C Regulation, Communication issues, Human Factors and the Digital I and C Licensing Process (currently issued as Draft). After allowing for further refinement based on additional technical insight gathered by NRC staff through near-term research and detailed review of relevant experience, it is expected that updated positions ultimately will be incorporated into regulatory guides and staff review procedures. This paper presents an overview of the guidance provided by the NRC-issued ISGs on key technology considerations (i.e., the first five documents above) for safety-related digital I and C systems.

  9. Common Cause Failure Analysis for the Digital Plant Protection System

    International Nuclear Information System (INIS)

    Kagn, Hyun Gook; Jang, Seung Cheol

    2005-01-01

    Safety-critical systems such as nuclear power plants adopt the multiple-redundancy design in order to reduce the risk from the single component failure. The digitalized safety-signal generation system is also designed based on the multiple-redundancy strategy which consists of more redundant components. The level of the redundant design of digital systems is usually higher than those of conventional mechanical systems. This higher redundancy would clearly reduce the risk from the single failure of components, but raise the importance of the common cause failure (CCF) analysis. This research aims to develop the practical and realistic method for modeling the CCF in digital safety-critical systems. We propose a simple and practical framework for assessing the CCF probability of digital equipment. Higher level of redundancy causes the difficulty of CCF analysis because it results in impractically large number of CCF events in the fault tree model when we use conventional CCF modeling methods. We apply the simplified alpha-factor (SAF) method to the digital system CCF analysis. The precedent study has shown that SAF method is quite realistic but simple when we consider carefully system success criteria. The first step for using the SAF method is the analysis of target system for determining the function failure cases. That is, the success criteria of the system could be derived from the target system's function and configuration. Based on this analysis, we can calculate the probability of single CCF event which represents the CCF events resulting in the system failure. In addition to the application of SAF method, in order to accommodate the other characteristics of digital technology, we develop a simple concept and several equations for practical use

  10. Digitized operator evaluation system for main control room of nuclear power plant

    International Nuclear Information System (INIS)

    Chen Yu; Yan Shengyuan; Chen Wenlong

    2014-01-01

    In order to evaluate the human-machine system matching relation of main control room in nuclear power plant accurately and efficiently, the expression and parameters of operator human body model were analyzed, and the evaluation required function of digital operator was determined. Based on the secondary development technology, the digital operator evaluation body model was developed. It could choose generation, gender, operation posture, single/eyes horizon, and left/right hand up to the domain according to the needs of specific evaluation, it was used to evaluate whether display information can be visible and equipment can be touch, and it also has key evaluation functions such as workspace and character visibility at the same time. The examples show that this method can complete the evaluation work of human-machine matching relation for main control room of nuclear power plant accurately, efficiently and quickly, and achieve the most optimal human-machine coordination relationship. (authors)

  11. Some aspects of digital I and C and digital human-system interface upgrades in nuclear power plants

    International Nuclear Information System (INIS)

    Mandic, D.

    2005-01-01

    Digital I and C technology introduces some new terms and new processes like software life cycle, process computer configuration control, digital human-system interface (HSI), software V and V (Verification and Validation), software common mode failure potential, software documentation, etc. Based on the experience from NEK, and other NPPs and published reports from other organizations, this paper sheds light on challenging tasks related to some aspects of the digital I and C upgrades and especially the NPP MCR/MCB HSI (Nuclear Power Plant Main Control Room / Main Control Board Human-System Interface) upgrade. The Ref. [1], EPRI Report TR-1008122 was used as a guidance to analyze original NEK MCR/MCB HSI design (1970s), to describe migration from the original MCR/MCB HSI design to the 2005 AS-BUILT status and to propose the authors vision for the key planning aspects for I and C upgrades and MCR modernization. This paper submits the justified proposal for the endpoint vision and the migration path applicable to NEK MCR/MCB HSI modernization, as well as some of the possible risks and lessons learned. (author)

  12. 77 FR 50720 - Test Documentation for Digital Computer Software Used in Safety Systems of Nuclear Power Plants

    Science.gov (United States)

    2012-08-22

    ... Used in Safety Systems of Nuclear Power Plants AGENCY: Nuclear Regulatory Commission. ACTION: Draft... Computer Software used in Safety Systems of Nuclear Power Plants.'' The DG-1207 is proposed Revision 1 of... for Digital Computer Software Used in Safety Systems of Nuclear Power Plants'' is temporarily...

  13. Safety and security aspects in design of digital safety I and C in nuclear power plants

    International Nuclear Information System (INIS)

    Ding, Yongjian; Waedt, Karl

    2016-01-01

    The paper describes a safety objective oriented systematic design approach of digital (computerized) safety I and C in modern nuclear power plants which considers the plant safety requirements as well as cybersecurity needs. The defence in depth philosophy is applied by using different defence lines in the I and C architecture and protection zones in the plant IT environment.

  14. Safety and security aspects in design of digital safety I and C in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yongjian [University of Applied Sciences Magdeburg-Stendal, Magdeburg (Germany). Inst. of Electrical Engineering; Waedt, Karl [Areva GmbH, Erlangen (Germany). PEAS-G

    2016-05-15

    The paper describes a safety objective oriented systematic design approach of digital (computerized) safety I and C in modern nuclear power plants which considers the plant safety requirements as well as cybersecurity needs. The defence in depth philosophy is applied by using different defence lines in the I and C architecture and protection zones in the plant IT environment.

  15. Digital Process Management Technology for Nuclear Power Plants

    International Nuclear Information System (INIS)

    You, Young M.; Suh, Kune Y.

    2009-01-01

    PHILOSOPHIA, Inc. and Seoul National University have utilized the cutting edge Digital Process Management (DPM) technology for the good of Nuclear Power Plant in recent days. This work represent the overall benefits and the use of this new flow of technology which come into the spotlight. Before realizing the three dimensional (3D) technologies and applying it to real mechanical manufactures and constructions, majority of planning and designing works need huge time and cost even if the process is before the real work. Especially, for a massive construction such as power plant and harbor, without computer-aided technology currently we cannot imagine the whole process can be established easily. Computer-aided Design (CAD) is now main and common technology for manufacturing or construction. This technology lead the other virtual reality 3D technologies into the job site. As a member of these new technologies, DPM is utilized in high-tech and huge scale manufacturing and construction for the benefits of time and cost

  16. Finnish experiences on licensing and using of programmable digital systems in nuclear power plants

    International Nuclear Information System (INIS)

    Haapanen, P.; Maskuniitty, M.; Heimburger, H.; Hall, L.E.; Manninen, T.

    1993-01-01

    Finnish utility companies, Imatran Voima Oy (IVO) and Teollisuuden Voima (TVO), and the licensing authority, the Finnish Centre for Radiation and Nuclear Safety (STUK), are preparing for a new nuclear power plant in Finland. Plant vendors are proposing programmable digital automation systems for both the safety-related and the operational I and C (instrumentation and control) systems in this new unit. Also in existing plant units the replacement of certain old analog systems with state-of-the-art digital ones will become necessary in the years to come. Licensing of programmable systems for safety critical applications requires a new approach due to the special properties and failure modes of these systems. The major difficulties seem to be in the assessment and quantification of software reliability. The Technical Research Centre of Finland has in co-operation with the authority and the utilities conducted a project (AJA) to develop domestically applicable licensing requirements, guidelines and practices. International standards, guidelines and licensing practices have been analyzed in order to specify national licensing requirements. The paper describes and discusses the findings and experiences of the AJA project so far. The experience in introducing advanced programmable digital control and computer systems in the operating nuclear power plants will be covered briefly. Although these systems are not safety-related but systems of more general interest regarding nuclear safety, some routines regarding the licensing of safety- related systems have been followed. In these backfitting and replacement projects some experience have been gained in how to license safety-related programmable systems. (Author) 31 refs., 2 figs

  17. A dependability modeling of software under hardware faults digitized system in nuclear power plants

    International Nuclear Information System (INIS)

    Choi, Jong Gyun

    1996-02-01

    An analytic approach to the dependability evaluation of software in the operational phase is suggested in this work with special attention to the physical fault effects on the software dependability : The physical faults considered are memory faults and the dependability measure in question is the reliability. The model is based on the simple reliability theory and the graph theory with the path decomposition micro model. The model represents an application software with a graph consisting of nodes and arcs that probabilistic ally determine the flow from node to node. Through proper transformation of nodes and arcs, the graph can be reduced to a simple two-node graph and the software failure probability is derived from this graph. This model can be extended to the software system which consists of several complete modules without modification. The derived model is validated by the computer simulation, where the software is transformed to a probabilistic control flow graph. Simulation also shows a different viewpoint of software failure behavior. Using this model, we predict the reliability of an application software and a software system in a digitized system(ILS system) in the nuclear power plant and show the sensitivity of the software reliability to the major physical parameters which affect the software failure in the normal operation phase. The derived model is validated by the computer simulation, where the software is transformed to a probabilistic control flow graph. Simulation also shows a different viewpoint of software failure behavior. Using this model, we predict the reliability of an application software and a software system in a digitized system (ILS system) is the nuclear power plant and show the sensitivity of the software reliability to the major physical parameters which affect the software failure in the normal operation phase. This modeling method is particularly attractive for medium size programs such as software used in digitized systems of

  18. Investigation of the impact of main control room digitalization on operators cognitive reliability in nuclear power plants.

    Science.gov (United States)

    Zhou, Yong; Mu, Haiying; Jiang, Jianjun; Zhang, Li

    2012-01-01

    Currently, there is a trend in nuclear power plants (NPPs) toward introducing digital and computer technologies into main control rooms (MCRs). Safe generation of electric power in NPPs requires reliable performance of cognitive tasks such as fault detection, diagnosis, and response planning. The digitalization of MCRs has dramatically changed the whole operating environment, and the ways operators interact with the plant systems. If the design and implementation of the digital technology is incompatible with operators' cognitive characteristics, it may have negative effects on operators' cognitive reliability. Firstly, on the basis of three essential prerequisites for successful cognitive tasks, a causal model is constructed to reveal the typical human performance issues arising from digitalization. The cognitive mechanisms which they impact cognitive reliability are analyzed in detail. Then, Bayesian inference is used to quantify and prioritize the influences of these factors. It suggests that interface management and unbalanced workload distribution have more significant impacts on operators' cognitive reliability.

  19. Testing methodology of embedded software in digital plant protection system

    International Nuclear Information System (INIS)

    Seong, Ah Young; Choi, Bong Joo; Lee, Na Young; Hwang, Il Soon

    2001-01-01

    It is necessary to assure the reliability of software in order to digitalize RPS(Reactor Protection System). Since RPS causes fatal damage on accidental cases, it is classified as Safety 1E class. Therefore we propose the effective testing methodology to assure the reliability of embedded software in the DPPS(Digital Plant Protection System). To test the embedded software effectively in DPPS, our methodology consists of two steps. The first is the re-engineering step that extracts classes from structural source program, and the second is the level of testing step which is composed of unit testing, Integration Testing and System Testing. On each testing step we test the embedded software with selected test cases after the test item identification step. If we use this testing methodology, we can test the embedded software effectively by reducing the cost and the time

  20. Application of Digital Technology for the Plant Protection System in Ulchin Nuclear Power Plant Units 5 and 6

    International Nuclear Information System (INIS)

    Deucksoo, Lee; Insik, Kim

    2006-01-01

    Since the completion of construction of Ulchin Nuclear Power Plant Units 3 and 4 (UCN 3 and 4), the first units of the OPR (Optimized Power Reactor) series, various advanced design features have been incorporated to the following OPRs. The Ulchin Nuclear Power Plant Units 5 and 6(UCN 5 and 6) which started commercial operation in Korea from 2004 and 2005 respectively, are designed to provide improvements in safety, reliability and costs by applying both advanced proven technology and experiences gained from the construction and operation of the previous OPRs. Among those improvements, the digital plant protection system (DPPS) and the digital engineered safety feature actuation system (DESFAS) are the key elements to the UCN 5 and 6 designs. The DPPS and DESFAS utilizing the digital computer technology offer a solution to the obsolescence problem of analog system. These features also provide the potential for additional benefits such as ease of maintenance, increased performance, reduction of internal and external cross channel wiring, improvement of the surveillance testability and flexibility of control logic programming change. During the initial design stage, the Korean regulatory body had evaluated these design concepts intensively and concluded it to be acceptable for the safety point of view. Also, in-depth review on the detailed design and the special evaluation/audit for the software design process has been performed to secure the quality of the software. As a result, every issue raised during licensing review has been clarified and the operating licenses for the UCN 5 and 6 were issued in October, 2003 and October, 2004 respectively, by the government. In this paper, design characteristics of the UCN 5 and 6 are introduced, and advanced design features and implementation process are presented focused on the DPPS/DESFAS with some benefit analysis results. (authors)

  1. Development of digital plant protection system for Korean Next Generation Reactor

    International Nuclear Information System (INIS)

    Suk-Joon Park

    1998-01-01

    A Digital Plant Protection System (DPPS) for Korean Next Generation Reactor (KNGR) is being developed using the Programmable Logic Controller (PLC) technology. For the design verification, the development of the DPPS prototype is progressing at this time. The prototype hardware equipment is installed and software coding is started. DPPS software is being coded by strict software V and V activities and function block language that uses simple graphical symbols. By adopting the PLC technology, the design of DPPS is possible to take full advantages in areas such as automatic testing, simplified calibration, improved isolation between redundant channels, reduced internal and external wiring and increased plant availability. (author)

  2. 78 FR 47011 - Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants

    Science.gov (United States)

    2013-08-02

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Unit Testing for Digital Computer Software... revised regulatory guide (RG), revision 1 of RG 1.171, ``Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants.'' This RG endorses American National Standards...

  3. 77 FR 50722 - Software Unit Testing for Digital Computer Software Used in Safety Systems of Nuclear Power Plants

    Science.gov (United States)

    2012-08-22

    ... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Software Unit Testing for Digital Computer Software...) is issuing for public comment draft regulatory guide (DG), DG-1208, ``Software Unit Testing for Digital Computer Software used in Safety Systems of Nuclear Power Plants.'' The DG-1208 is proposed...

  4. Development of digital plant protection system for Korean Next Generation Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Suk-Joon [NSSS Engineering and Development Division, Korea Power Engineering Company, Taejon (Korea, Republic of)

    1998-10-01

    A Digital Plant Protection System (DPPS) for Korean Next Generation Reactor (KNGR) is being developed using the Programmable Logic Controller (PLC) technology. For the design verification, the development of the DPPS prototype is progressing at this time. The prototype hardware equipment is installed and software coding is started. DPPS software is being coded by strict software V and V activities and function block language that uses simple graphical symbols. By adopting the PLC technology, the design of DPPS is possible to take full advantages in areas such as automatic testing, simplified calibration, improved isolation between redundant channels, reduced internal and external wiring and increased plant availability. (author) 8 refs, 4 figs, 3 tabs

  5. Comparación de un control lineal y no lineal en un levitador magnético

    Directory of Open Access Journals (Sweden)

    Jonathan Smith Castro Beltrán

    2018-02-01

    Full Text Available El artículo presenta los diseños y resultados de dos controladores tipo SISO de posición para un levitador magnético convencional, con la motivación de comparar las dinámicas de los sistemas posterior a la implementación de ambos métodos de control. Para el diseño de los controladores se obtuvo el modelo matemático aproximado de un levitador magnético a partir de características estáticas, de fuerza electromagnética e inductancia. Una vez establecido el modelo matemático se planteó una ley de control lineal a partir de una realimentación de estados con integrador, estimando la velocidad y corriente. Para el diseño del control no lineal se propuso una ley de control de tipo linealización entrada salida. Por último, se comparó la dinámica del sistema con los controladores implementados y se realizaron modificaciones de masa para verificar la robustez de los controladores, además de perturbaciones tales como fuerzas externas y ruido de tipo eléctrico. Finalmente, fue posible concluir que el controlador lineal tiene una respuesta satisfactoria en términos de error de estado estacionario, añadiendo un menor costo de procesamiento en comparación al controlador no lineal.

  6. Effects of digital human-machine interface characteristics on human error in nuclear power plants

    International Nuclear Information System (INIS)

    Li Pengcheng; Zhang Li; Dai Licao; Huang Weigang

    2011-01-01

    In order to identify the effects of digital human-machine interface characteristics on human error in nuclear power plants, the new characteristics of digital human-machine interface are identified by comparing with the traditional analog control systems in the aspects of the information display, user interface interaction and management, control systems, alarm systems and procedures system, and the negative effects of digital human-machine interface characteristics on human error are identified by field research and interviewing with operators such as increased cognitive load and workload, mode confusion, loss of situation awareness. As to the adverse effects related above, the corresponding prevention and control measures of human errors are provided to support the prevention and minimization of human errors and the optimization of human-machine interface design. (authors)

  7. Digital Actuator Technology

    Energy Technology Data Exchange (ETDEWEB)

    Ken Thomas; Ted Quinn; Jerry Mauck; Richard Bockhorst

    2014-09-01

    There are significant developments underway in new types of actuators for power plant active components. Many of these make use of digital technology to provide a wide array of benefits in performance of the actuators and in reduced burden to maintain them. These new product offerings have gained considerable acceptance in use in process plants. In addition, they have been used in conventional power generation very successfully. This technology has been proven to deliver the benefits promised and substantiate the claims of improved performance. The nuclear industry has been reluctant to incorporate digital actuator technology into nuclear plant designs due to concerns due to a number of concerns. These could be summarized as cost, regulatory uncertainty, and a certain comfort factor with legacy analog technology. The replacement opportunity for these types of components represents a decision point for whether to invest in more modern technology that would provide superior operational and maintenance benefits. Yet, the application of digital technology has been problematic for the nuclear industry, due to qualification and regulatory issues. With some notable exceptions, the result has been a continuing reluctance to undertake the risks and uncertainties of implementing digital actuator technology when replacement opportunities present themselves. Rather, utilities would typically prefer to accept the performance limitations of the legacy analog actuator technologies to avoid impacts to project costs and schedules. The purpose of this report is to demonstrate that the benefits of digital actuator technology can be significant in terms of plant performance and that it is worthwhile to address the barriers currently holding back the widespread development and use of this technology. It addresses two important objectives in pursuit of the beneficial use of digital actuator technology for nuclear power plants: 1. To demonstrate the benefits of digital actuator

  8. Digital Processor Module Reliability Analysis of Nuclear Power Plant

    International Nuclear Information System (INIS)

    Lee, Sang Yong; Jung, Jae Hyun; Kim, Jae Ho; Kim, Sung Hun

    2005-01-01

    The system used in plant, military equipment, satellite, etc. consists of many electronic parts as control module, which requires relatively high reliability than other commercial electronic products. Specially, Nuclear power plant related to the radiation safety requires high safety and reliability, so most parts apply to Military-Standard level. Reliability prediction method provides the rational basis of system designs and also provides the safety significance of system operations. Thus various reliability prediction tools have been developed in recent decades, among of them, the MI-HDBK-217 method has been widely used as a powerful tool for the prediction. In this work, It is explained that reliability analysis work for Digital Processor Module (DPM, control module of SMART) is performed by Parts Stress Method based on MIL-HDBK-217F NOTICE2. We are using the Relex 7.6 of Relex software corporation, because reliability analysis process requires enormous part libraries and data for failure rate calculation

  9. Resolution of digital instrumentation and control and human factors technical and regulatory issues for new plants and for modernization of operating plants

    International Nuclear Information System (INIS)

    Naser, J.A.; Torok, R.C.; Canavan, K.T.

    2008-01-01

    There are several technical and regulatory issues in the areas of digital I and C, human factors, and control rooms needing generic resolution. If they are not generically resolved, they can contribute to protracted regulatory reviews for operating plant license amendments and substantial delays and increased costs for new plant COL approvals. Therefore; a coordinated, proactive program has been established to resolve key issues. Both Industry and NRC have roles in resolving these key issues and addressing them in future design efforts and regulatory reviews. The Industry initiative is led by the NEI Digital I and C and Human Factors Working Group. NRC has established Task Working Groups under the NRC Digital I and C Steering Committee to address the issues and interact with Industry. EPRI is providing technical input and resolution leadership for some of the issues being addressed in three of the task working groups. For the Highly Integrated Control Room - Human Factors Task area, EPRI has taken the lead in developing draft industry position technical reports for the following three issues: 1) Minimum inventory of human system interfaces, 2) Computerized procedures and associated topics of automation and soft controls, and 3) Methodology to determine the acceptability of manual operator actions response times for a BTP 7-19 software common cause failure. For the Diversity and Defense-in-Depth area, EPRI has taken the lead in developing two draft industry position technical papers on the following topics: 1) Integrating defensive measures and diversity attributes to protect against digital common cause failures and 2) Susceptibility of digital devices and components to common cause failures. For the Risk Informing area, EPRI has taken the lead in developing two draft industry position technical papers on the following topics: 1) Clarifying how to use current methods to model digital systems in a PRA and 2) Application of PRA to specific digital I and C issues

  10. Application of digital solutions to help the safe and efficient operation of nuclear power plants

    International Nuclear Information System (INIS)

    Ortega P, F.; Fernandez F, S.

    2017-09-01

    In the search for excellence, the emergence of solutions to digitize nuclear power plants is an opportunity to optimize the operation and safety of them. The new technologies available today in the market, applied under a global vision of the operation, can contribute to the excellent operation of nuclear power plants in terms of efficiency and effectiveness. Tecnatom has a long experience in various areas related to the operation of the plants, giving the aforementioned global vision, essential to develop global solutions that pursue the safe and efficient operation of the operation. (Author)

  11. Advanced digital instrumentation and control system for nuclear power plant protection

    Energy Technology Data Exchange (ETDEWEB)

    Sabino, D [VVER Engineering, Westinghouse Electric Corporation (United States)

    1998-12-31

    The Diverse Protection System is a back-up to the Primary Reactor Protection System developed for use at the Temelin nuclear power plant. The DPS is a digital system which provides a wealth of benefits from today`s advanced technology. These benefits include a compact hardware design with high performance microprocessors and a structured software design using a high level language. An overview of the DPS functions, hardware and software is provided. (author). 1 fig., 1 tab.

  12. Digital I and C and Cyber Security for Nuclear Power Plants

    International Nuclear Information System (INIS)

    An, Yong Kyu; Chen, Daniel; Kalbarczyk, Zbigniew; Sollima, Calogero; Uddin, Rizwan

    2014-01-01

    Efforts are underway to switch existing nuclear power plants (NPPs) based on analog to digital control systems, while digital I and C systems are expected to be used in all new NPPs. Digital I and C is expected to solve obsolescence problem of analog components, and improve safety and performance. However, before analog systems can be switched to digital, much work needs to be done to ensure nuclear-grade safety and reliability of these completely new or hybrid systems. The goals of this research project are to identify possible faults and to evaluate resiliency of safety-critical digital I and C systems destined to be used in NPPs. A test bed is being developed for this purpose. This test bed consists of a model of a reactor, a digital controller, and associated communication links. The digital controller has a Triple-Modular Redundant (TMR) architecture to ensure continuous availability of the controller. A simple real time NPP simulator has been developed in LabVIEW using the point kinetics equation for the core, and models for a pressurizer, and a pump. The model for the primary loop is fairly complete, while that for the secondary loop is still in progress. The NPP simulator and the TMR controller, with its associated application program, have been assembled, and communications between them are established. The test bed also includes a set of specialized fault/error injectors to inject different types of faults/errors including both transients and permanents. A fault injection module is developed in LabVIEW in order to simulate hardware failures. The module contains a fault list manager (FLM), a fault injection manager (FIM), and a result analyzer. FLM picks a fault type and fault location at random from the pre-generated list of fault locations and types, and communicates this information to FIM, which injects faults into the system. The paper describes the details of the test bed, the associated fault injection system, and the results of the fault injection

  13. Digital I and C and Cyber Security for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    An, Yong Kyu; Chen, Daniel; Kalbarczyk, Zbigniew; Sollima, Calogero; Uddin, Rizwan [University of Illinois at Urbana-Champaign, Urbana (United States)

    2014-08-15

    Efforts are underway to switch existing nuclear power plants (NPPs) based on analog to digital control systems, while digital I and C systems are expected to be used in all new NPPs. Digital I and C is expected to solve obsolescence problem of analog components, and improve safety and performance. However, before analog systems can be switched to digital, much work needs to be done to ensure nuclear-grade safety and reliability of these completely new or hybrid systems. The goals of this research project are to identify possible faults and to evaluate resiliency of safety-critical digital I and C systems destined to be used in NPPs. A test bed is being developed for this purpose. This test bed consists of a model of a reactor, a digital controller, and associated communication links. The digital controller has a Triple-Modular Redundant (TMR) architecture to ensure continuous availability of the controller. A simple real time NPP simulator has been developed in LabVIEW using the point kinetics equation for the core, and models for a pressurizer, and a pump. The model for the primary loop is fairly complete, while that for the secondary loop is still in progress. The NPP simulator and the TMR controller, with its associated application program, have been assembled, and communications between them are established. The test bed also includes a set of specialized fault/error injectors to inject different types of faults/errors including both transients and permanents. A fault injection module is developed in LabVIEW in order to simulate hardware failures. The module contains a fault list manager (FLM), a fault injection manager (FIM), and a result analyzer. FLM picks a fault type and fault location at random from the pre-generated list of fault locations and types, and communicates this information to FIM, which injects faults into the system. The paper describes the details of the test bed, the associated fault injection system, and the results of the fault injection

  14. Fault-tolerant design of adaptive digital control systems for power plant components

    International Nuclear Information System (INIS)

    Parlos, A.G.; Menon, S.K.

    1992-01-01

    An adaptive controller has been designed for the water level of a Westinghouse type U-tube steam generator, and its operation has been demonstrated in the entire power range via computer simulations. The proposed design exhibits improved performance, at low operating powers, a,s compared to existing controller types. The continuous-time controller design is performed systematically via the Linear Quadratic Gaussian/Loop Transfer Recovery method, followed by gain adaptation allowing controller operation in the entire power range. Digital implementation of the controller is accomplished by a digital redesign which results in matching the digital and continuous-time system and controller states. It is only at this stage of the control system design process that issues such as microprocessor induced quantization effects are taken into account. The use of computer-aided-design software greatly expedites the design cycle, allowing the designer to maximize the controller stability robustness to uncertainties via numerous iterations. This inherent controller robustness can be exploited to tolerate incipient plant faults, such as deteriorating U-tube heat transfer properties, without significant loss of controller performance

  15. Digital controls for plant control systems at the Ulchin 5 and 6 NPP: Lessons for the U.S. NPP retrofits?

    International Nuclear Information System (INIS)

    McCreary, T.; Stevens, J.

    2006-01-01

    South Korea, through its nuclear operating arm, Korea Hydro and Nuclear Power, Ltd. (KHNP), has been one of the leading countries in the routine construction and operation of nuclear power plants. While standardizing on certain design approaches in the plant, KHNP continues to stress the need for the most reliable and cutting edge I and C technologies available for safety and non safety related NSSS and BOP functions. Its specifications are among the most challenging in the world with regard to the system performance and reliability requirements that must be met for the systems to be supplied. The Ulchin Units 5 and 6 (1000 MW each) nuclear power plants have been recently commissioned (2004 and 2005 respectively) with advanced programmable digital control systems in the NSSS and BOP (which includes both safety and non-safety applications). The systems supplied met what the authors believe are the most rigorous performance and functional specification criteria in use today. The authors will highlight a number of the specification requirements, the rationale for same and the plant experiences in the resultant supplied systems. As the existing U.S. nuclear fleet is faced with the prospect of upgrading legacy controls with digital controls, there are valuable lessons to be learned in the Ulchin 5 and 6 experiences that can be applied to retrofits and even new U.S. plant designs. Ulchin 5 and 6 is one of the success stories in the application of advanced digital technology to nuclear power plants. The specification focus that guided the selection and project execution for the digital controls supplied for Ulchin was on several key areas: a) a high reliable fault tolerant system, b)functional segmentation to minimize the failure effects on operation, c) validation and verification of the owner's engineer's application design (for regulatory compliance) as well as validation and verification of the system architecture and operation (to assure system performance met

  16. A REVIEW ON DIAGNOSIS OF NUTRIENT DEFICIENCY SYMPTOMS IN PLANT LEAF IMAGE USING DIGITAL IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    S Jeyalakshmi

    2017-05-01

    Full Text Available Plants, for their growth and survival, need 13 mineral nutrients. Toxicity or deficiency in any one or more of these nutrients affects the growth of plant and may even cause the destruction of the plant. Hence, a constant monitoring system for tracking the nutrient status in plants becomes essential for increase in production as well as quality of yield. A diagnostic system using digital image processing would diagnose the deficiency symptoms much earlier than human eyes could recognize. This will enable the farmers to adopt appropriate remedial action in time. This paper focuses on the review of work using image processing techniques for diagnosing nutrient deficiency in plants.

  17. Reliability analysis of operator's monitoring behavior in digital main control room of nuclear power plants and its application

    International Nuclear Information System (INIS)

    Zhang Li; Hu Hong; Li Pengcheng; Jiang Jianjun; Yi Cannan; Chen Qingqing

    2015-01-01

    In order to build a quantitative model to analyze operators' monitoring behavior reliability of digital main control room of nuclear power plants, based on the analysis of the design characteristics of digital main control room of a nuclear power plant and operator's monitoring behavior, and combining with operators' monitoring behavior process, monitoring behavior reliability was divided into three parts including information transfer reliability among screens, inside-screen information sampling reliability and information detection reliability. Quantitative calculation model of information transfer reliability among screens was established based on Senders's monitoring theory; the inside screen information sampling reliability model was established based on the allocation theory of attention resources; and considering the performance shaping factor causality, a fuzzy Bayesian method was presented to quantify information detection reliability and an example of application was given. The results show that the established model of monitoring behavior reliability gives an objective description for monitoring process, which can quantify the monitoring reliability and overcome the shortcomings of traditional methods. Therefore, it provides theoretical support for operator's monitoring behavior reliability analysis in digital main control room of nuclear power plants and improves the precision of human reliability analysis. (authors)

  18. Implementation of a digital feedwater control system at Dresden Nuclear Power Plant, Units 2 and 3: Final report

    International Nuclear Information System (INIS)

    Zapotocky, A.; Popovic, J.R.; Fournier, R.D.

    1988-12-01

    This report describes the Digital Feedwater Control System Implementation at the Dresden 2 or 3 Units of the BWR Nuclear Power Plant owned by the Commonwealth Edison Company. The digital system has been operational in Unit 3 since August 1986, and in Unit 2 since April 1987. The Bailey Control's Network 90 based digital control system replaced the obsolete GE/MAC 5000 analog control system in the reactor feedwater control loop as a ''like-for-like'' replacement. Operational experience from the Digital Feedwater Control installations has been good and the system demonstrated better performance than the old analog systems. 14 refs., 15 figs., 17 tabs

  19. On the simulation of transients and accidents in PWRs with digital instrumentation and control using an LQR digital controller

    International Nuclear Information System (INIS)

    Alvarenga, M.A.B.; Melo, P.F. Frutuoso e; Medeiros, J.A.C.C.; Oliva, J.J. Rivero

    2015-01-01

    New nuclear power plant designs are including integrated I and C digital systems for protection, control, alarming and monitoring. Existing operating nuclear power plants, as is the case of Angra 1 nuclear power plant, have to consider the replacement of their I and C analog systems by digital systems for retrofitting their facilities. However, before replacing the analog control loops by digital ones it is necessary to design and evaluate their performance, which requires modeling of the plant and its control system with extensive simulations under several normal and abnormal operation conditions. This paper discusses the use of a linear quadratic regulator (LQR) digital controller for evaluating the plant stability behavior before the actuation of the reactor protection system. The objective is to evaluate the effect of digital controllers on plant behavior for several transients and accident conditions. For this purpose, a numerical model was developed and implemented as a MatlabTM tool. This paper discusses an adequate framework in order to simulate a set of transients and accidents that constitute the design basis in the final safety analysis report of PWR power plants to evaluate the performance of digital controllers such as LQR regulators.(author)

  20. Optimal testing input sets for reduced diagnosis time of nuclear power plant digital electronic circuits

    International Nuclear Information System (INIS)

    Kim, D.S.; Seong, P.H.

    1994-01-01

    This paper describes the optimal testing input sets required for the fault diagnosis of the nuclear power plant digital electronic circuits. With the complicated systems such as very large scale integration (VLSI), nuclear power plant (NPP), and aircraft, testing is the major factor of the maintenance of the system. Particularly, diagnosis time grows quickly with the complexity of the component. In this research, for reduce diagnosis time the authors derived the optimal testing sets that are the minimal testing sets required for detecting the failure and for locating of the failed component. For reduced diagnosis time, the technique presented by Hayes fits best for the approach to testing sets generation among many conventional methods. However, this method has the following disadvantages: (a) it considers only the simple network (b) it concerns only whether the system is in failed state or not and does not provide the way to locate the failed component. Therefore the authors have derived the optimal testing input sets that resolve these problems by Hayes while preserving its advantages. When they applied the optimal testing sets to the automatic fault diagnosis system (AFDS) which incorporates the advanced fault diagnosis method of artificial intelligence technique, they found that the fault diagnosis using the optimal testing sets makes testing the digital electronic circuits much faster than that using exhaustive testing input sets; when they applied them to test the Universal (UV) Card which is a nuclear power plant digital input/output solid state protection system card, they reduced the testing time up to about 100 times

  1. 1985 seminar on power plant digital control and fault-tolerant microcomputers: proceedings

    International Nuclear Information System (INIS)

    Divakaruni, S.M.

    1986-09-01

    An EPRI Seminar to address Power Plant Digital Controls and Fault-Tolerant Microcomputers Technology was hosted by Arizona Public Service Company in Phoenix, Arizona on April 9-12, 1986. The attendees represented a broad spectrum of US and foreign utilities, architect and consulting firms, and NSSS and computer system hardware vendors. These proceedings contain the text of the formal presentations as well as the papers and slides used during the short courses offered

  2. Advanced digital I ampersand C systems in nuclear power plants: Risk- sensitivities to environmental stressors

    International Nuclear Information System (INIS)

    Hassan, M.; Vesely, W.E.

    1996-01-01

    Microprocessor-based advanced digital systems are being used for upgrading analog instrumentation and control (I ampersand C) systems in nuclear power plants (NPPs) in the United States. A concern with using such advanced systems for safety-related applications in NPPs is the limited experience with this equipment in these environments. In this study, we investigate the risk effects of environmental stressors by quantifying the plant's risk-sensitivities to them. The risk- sensitivities are changes in plant risk caused by the stressors, and are quantified by estimating their effects on I ampersand C failure occurrences and the consequent increase in risk in terms of core damage frequency (CDF). We used available data, including military and NPP operating experience, on the effects of environmental stressors on the reliability of digital I ampersand C equipment. The methods developed are applied to determine and compare risk-sensitivities to temperature, humidity, vibration, EMI (electromagnetic interference) from lightning and smoke as stressors in an example plant using a PRA (Probabilistic Risk Assessment). Uncertainties in the estimates of the stressor effects on the equipment's reliability are expressed in terms of ranges for risk-sensitivities. The results show that environmental stressors potentially can cause a significant increase in I ampersand C contributions to the CDF. Further, considerable variations can be expected in some stressor effects, depending on where the equipment is located

  3. Lessons learned in digital upgrade projects digital control system implementation at US nuclear power stations

    International Nuclear Information System (INIS)

    Kelley, S.; Bolian, T. W.

    2006-01-01

    AREVA NP has gained significant experience during the past five years in digital upgrades at operating nuclear power stations in the US. Plants are seeking modernization with digital technology to address obsolescence, spare parts availability, vendor support, increasing age-related failures and diminished reliability. New systems offer improved reliability and functionality, and decreased maintenance requirements. Significant lessons learned have been identified relating to the areas of licensing, equipment qualification, software quality assurance and other topics specific to digital controls. Digital control systems have been installed in non safety-related control applications at many utilities within the last 15 years. There have also been a few replacements of small safety-related systems with digital technology. Digital control systems are proving to be reliable, accurate, and easy to maintain. Digital technology is gaining acceptance and momentum with both utilities and regulatory agencies based upon the successes of these installations. Also, new plants are being designed with integrated digital control systems. To support plant life extension and address obsolescence of critical components, utilities are beginning to install digital technology for primary safety-system replacement. AREVA NP analyzed operating experience and lessons learned from its own digital upgrade projects as well as industry-wide experience to identify key issues that should be considered when implementing digital controls in nuclear power stations

  4. Development of Testing Platform for Digital I and C System in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Park, G. Y.; Kim, Y. M.; Jeong, C. H. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2013-10-15

    According to digitalization of the NPP (Nuclear Power Plant) I and C (Instrumentation and Control) system, cyber threats against I and C system are increased. Moreover, the complexity of I and C system are increased due to adopt the up-to-date technologies (i. e., smart sensor, wireless network, and Field Programmable Gate Array / Complex Programmable Logic Device) into NPP's I and C system. For example, new issues such as cyber threat are introduced from digitalized I and C systems and components to replace obsolete analog equipment in existing NPPs. Furthermore, use of wireless communication, FPGA/CPLD, and smart sensor could introduce new considerations such as Defense-in-Depth and Diversity. Therefore, the proof testing for digital I and C system is required to verify the adverse effect from use of up-to-date digital technologies and identify the criteria to resolve and mitigate (or prevent) the (possibility of) effects. The objective of this study is developing the Testing Platform for the proof testing. The digital I and C System Test Platform is implemented using test platform hardware, component software, and architectural design. The digital I and C testing platform includes the safety-related PLC and relevant ladder logics, Windows-based C++ codes for host PC. For software, there are seven spike models to confirm the each module's functionality and generate/monitor the signals to/from PLCs. For future work, digital I and C System Test Platform architecture will be implemented using spike models. And a set of acceptance test against cyber security, smart sensor, wireless network, and FPGA/CPLD will be conducted using digital I and C System Test Platform.

  5. Development of Testing Platform for Digital I and C System in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Park, G. Y.; Kim, Y. M.; Jeong, C. H.

    2013-01-01

    According to digitalization of the NPP (Nuclear Power Plant) I and C (Instrumentation and Control) system, cyber threats against I and C system are increased. Moreover, the complexity of I and C system are increased due to adopt the up-to-date technologies (i. e., smart sensor, wireless network, and Field Programmable Gate Array / Complex Programmable Logic Device) into NPP's I and C system. For example, new issues such as cyber threat are introduced from digitalized I and C systems and components to replace obsolete analog equipment in existing NPPs. Furthermore, use of wireless communication, FPGA/CPLD, and smart sensor could introduce new considerations such as Defense-in-Depth and Diversity. Therefore, the proof testing for digital I and C system is required to verify the adverse effect from use of up-to-date digital technologies and identify the criteria to resolve and mitigate (or prevent) the (possibility of) effects. The objective of this study is developing the Testing Platform for the proof testing. The digital I and C System Test Platform is implemented using test platform hardware, component software, and architectural design. The digital I and C testing platform includes the safety-related PLC and relevant ladder logics, Windows-based C++ codes for host PC. For software, there are seven spike models to confirm the each module's functionality and generate/monitor the signals to/from PLCs. For future work, digital I and C System Test Platform architecture will be implemented using spike models. And a set of acceptance test against cyber security, smart sensor, wireless network, and FPGA/CPLD will be conducted using digital I and C System Test Platform

  6. Advanced Reactor Licensing: Experience with Digital I&C Technology in Evolutionary Plants

    Energy Technology Data Exchange (ETDEWEB)

    Wood, RT

    2004-09-27

    This report presents the findings from a study of experience with digital instrumentation and controls (I&C) technology in evolutionary nuclear power plants. In particular, this study evaluated regulatory approaches employed by the international nuclear power community for licensing advanced l&C systems and identified lessons learned. The report (1) gives an overview of the modern l&C technologies employed at numerous evolutionary nuclear power plants, (2) identifies performance experience derived from those applications, (3) discusses regulatory processes employed and issues that have arisen, (4) captures lessons learned from performance and regulatory experience, (5) suggests anticipated issues that may arise from international near-term deployment of reactor concepts, and (6) offers conclusions and recommendations for potential activities to support advanced reactor licensing in the United States.

  7. Advanced digital instrumentation and control system for nuclear power plant protection

    International Nuclear Information System (INIS)

    Sabino, D.

    1997-01-01

    The Diverse Protection System (DPS) is described. The DPS is a state-of-the-art digital protection system developed as a back-up to the primary reactor protection system at the Temelin nuclear power plant, featuring a compact hardware design based on VMEbus technology. This technology allows for ease in adding or modifying the number and type of input modules and processors. The DPS software is written in a high level language suitable for safety critical applications. The software is both modular and configurable allowing for potential future modifications and software reuse

  8. A REVIEW OF HUMAN-SYSTEM INTERFACE DESIGN ISSUES OBSERVED DURING ANALOG-TO-DIGITAL AND DIGITAL-TO-DIGITAL MIGRATIONS IN U.S. NUCLEAR POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Kovesdi, C.; Joe, J.

    2017-05-01

    The United States (U.S.) Department of Energy (DOE) Light Water Reactor Sustainability (LWRS) program is developing a scientific basis through targeted research and development (R&D) to support the U.S. nuclear power plant (NPP) fleet in extending their existing licensing period and ensuring their long-term reliability, productivity, safety, and security. Over the last several years, human factors engineering (HFE) professionals at the Idaho National Laboratory (INL) have supported the LWRS Advanced Instrumentation, Information, and Control (II&C) System Technologies pathway across several U.S. commercial NPPs in analog-to-digital migrations (i.e., turbine control systems) and digital-to-digital migrations (i.e., Safety Parameter Display System). These efforts have included in-depth human factors evaluation of proposed human-system interface (HSI) design concepts against established U.S. Nuclear Regulatory Commission (NRC) design guidelines from NUREG-0700, Rev 2 to inform subsequent HSI design prior to transitioning into Verification and Validation. This paper discusses some of the overarching design issues observed from these past HFE evaluations. In addition, this work presents some observed challenges such as common tradeoffs utilities are likely to face when introducing new HSI technologies into NPP hybrid control rooms. The primary purpose of this work is to distill these observed design issues into general HSI design guidance that industry can use in early stages of HSI design.

  9. Neural network based control of an absorption column in the process of bioethanol production

    Directory of Open Access Journals (Sweden)

    Eduardo Eyng

    2009-08-01

    Full Text Available Gaseous ethanol may be recovered from the effluent gas mixture of the sugar cane fermentation process using a staged absorption column. In the present work, the development of a nonlinear controller, based on a neural network inverse model (ANN controller, was proposed and tested to manipulate the absorbent flow rate in order to control the residual ethanol concentration in the effluent gas phase. Simulation studies were carried out, in which a noise was applied to the ethanol concentration signals from the rigorous model. The ANN controller outperformed the dynamic matrix control (DMC when step disturbances were imposed to the gas mixture composition. A security device, based on a conventional feedback algorithm, and a digital filter were added to the proposed strategy to improve the system robustness when unforeseen operating and environmental conditions occured. The results demonstrated that ANN controller was a robust and reliable tool to control the absorption column.Deseja-se recuperar o etanol perdido por evaporação durante o processo de fermentação da cana-de-açúcar. Para tanto, faz-se uso de uma coluna de absorção. O controle da concentração de etanol no efluente gasoso da coluna é realizado pela manipulação da vazão de solvente, sendo esta determinada pelo controlador não linear proposto, baseado em um modelo inverso de redes neurais (controlador ANN. Foram feitas simulações adicionando-se um sinal de ruído a medida de concentração de etanol na fase gasosa. Quando perturbações degrau foram inseridas na mistura gasosa afluente, o controlador ANN demonstrou desempenho superior ao controle por matriz dinâmica (DMC. Um dispositivo de segurança, baseado em um controlador feedback convencional, e um filtro digital foram implementados à estratégia de controle proposta para agregar robustez no tratamento de distúrbios ocorridos no ambiente operacional. Os resultados demonstraram que o controlador ANN é uma

  10. Research on real-time simulation test for upgrades of digital I and C system in nuclear power plant

    International Nuclear Information System (INIS)

    Shi Ji; Jiang Mingyu; Ma Yunqin

    2005-01-01

    The developing trend that digital instrument and control (I and C) system will supplant traditional analog I and C system in nuclear power plant is emphasized. This paper introduces mathematical model of steam generator of full scope simulator for nuclear power plant. The independent real-time simulation system, which forms the interactive closed loop together with the steam generator control system, can be applied to provide a simulation target for upgrades of instrument and control system and the research of control schemes. At the same time, a simulation method for this purpose is presented in this paper. In this method all of the hardware and software are composed of real distributed control system except the model of controlled object. This will not only create favorable conditions for commissioning on site in the future, but also give a theoretical analysis for upgrades of digital I and C system in nuclear power plant. (authors)

  11. Atucha II nuclear power plant digital simulation

    International Nuclear Information System (INIS)

    Santome, D.; Rovere, L.A.T.

    1987-01-01

    This paper describes the start-up of a digital simulation code apt to be performed in real time of Atucha II nuclear power plant, foreseeing its subsequent usage in a Basic Principles Simulator. Adaptability and modification of existing routines and development of modules in order to incorporate the necessary variables dynamics to couple the different modes, were the main tasks. The mathematical model used allows the representation of the following sub-systems: a) a reactor's core point model, which comprehends the neutronic kinetics, fission and decaying powers, thermal transfer and Xe-poisoning calculation; b) pressurizer, which considers two sub-systems that may or may not be in thermodynamic equilibrium, both in two phases; c) coolants and moderators bonds considering separate moderator loops with the aim of introducing asymmetric perturbations; d) secondary sub-subsystem, which includes the feed water loop, pumps, steam generators and control valves; e) steam generators; f) control and safety systems, including power control, steam generators levels, moderator's temperature primary loop system, limitations and protection. (Author)

  12. Digital simulation of a commercial scale high temperature gas-cooled reactor (HTGR) steam power plant

    International Nuclear Information System (INIS)

    Ray, A.; Bowman, H.F.

    1978-01-01

    A nonlinear dynamic model of a commercial scale high temperature gas-cooled reactor (HTGR) steam power plant was derived in state-space form from fundamental principles. The plant model is 40th order, time-invariant, deterministic and continuous-time. Numerical results were obtained by digital simulation. Steady-state performance of the nonlinear model was verified with plant heat balance data at 100, 75 and 50 percent load levels. Local stability, controllability and observability were examined in this range using standard linear algorithms. Transfer function matrices for the linearized models were also obtained. Transient response characteristics of 6 system variables for independent step distrubances in 2 different input variables are presented as typical results

  13. Cyber Threat and vulnerability Analysis for Digital Assets of NPPs

    International Nuclear Information System (INIS)

    Oh, Eun Se; Seo, In Yong; Kim, See Hong

    2009-01-01

    Today's computer and communication technology breakthrough make increase plant floor replacement from analog instrumentation and control systems of nuclear power plants to a full-fledged digital system . The rich functionality and crisp accuracy are one of big advantages of digital technology adaptation, but use of open networks and inherited shared system resources (memory, network, etc.) are well known weak points of digital system. Intended or un-intended cyber attack throughout power plant digital control system's weak point may result to wide area of system failures and that easily defeats system operation and multiple protection safeguards. Well organized cyber security analysis for nuclear plant digital control systems (digital assets) are required

  14. Suitability review of FMEA and reliability analysis for digital plant protection system and digital engineered safety features actuation system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, I. S.; Kim, T. K.; Kim, M. C.; Kim, B. S.; Hwang, S. W.; Ryu, K. C. [Hanyang Univ., Seoul (Korea, Republic of)

    2000-11-15

    Of the many items that should be checked out during a review stage of the licensing application for the I and C system of Ulchin 5 and 6 units, this report relates to a suitability review of the reliability analysis of Digital Plant Protection System (DPPS) and Digital Engineered Safety Features Actuation System (DESFAS). In the reliability analysis performed by the system designer, ABB-CE, fault tree analysis was used as the main methods along with Failure Modes and Effect Analysis (FMEA). However, the present regulatory technique dose not allow the system reliability analysis and its results to be appropriately evaluated. Hence, this study was carried out focusing on the following four items ; development of general review items by which to check the validity of a reliability analysis, and the subsequent review of suitability of the reliability analysis for Ulchin 5 and 6 DPPS and DESFAS L development of detailed review items by which to check the validity of an FMEA, and the subsequent review of suitability of the FMEA for Ulchin 5 and 6 DPPS and DESFAS ; development of detailed review items by which to check the validity of a fault tree analysis, and the subsequent review of suitability of the fault tree for Ulchin 5 and 6 DPPS and DESFAS ; an integrated review of the safety and reliability of the Ulchin 5 and 6 DPPS and DESFAS based on the results of the various reviews above and also of a reliability comparison between the digital systems and the comparable analog systems, i.e., and analog Plant Protection System (PPS) and and analog Engineered Safety Features Actuation System (ESFAS). According to the review mentioned above, the reliability analysis of Ulchin 5 and 6 DPPS and DESFAS generally satisfies the review requirements. However, some shortcomings of the analysis were identified in our review such that the assumed test periods for several equipment were not properly incorporated in the analysis, and failures of some equipment were not included in the

  15. Model for impact assessment in human factors engineering project of PWR plants with digital control

    International Nuclear Information System (INIS)

    Roedel, Frederico G.; Schirru, Roberto

    2017-01-01

    New nuclear power plants are being designed with the digital Instrumentation and Control (I and C) as the backbone for the functions of protection, control, monitoring and display and with digital Human-System Interface (HSI). In this new environment, rather than play physical control actions, the operators begin to act as decision makers and, within this context, the Human Factors Engineering (HFE) has become an integral part of the projects. As the operational experience with the use of digital I and C systems and HSI is limited since, besides the small number of applications, it is proprietary, the objective of this work is to carry out an assessment in order to identify the most relevant aspects of a digital HSI project. The proposed model is based on concepts of fuzzy logic, uses MATLAB for data processing, defines criteria for evaluation and quantification of impacts in the project and has been applied to the General Principles and the Guidelines presented in the NUREG-0700. The assessment indicated that the Guidelines for User-Interface Interaction and Management, for Information Display and for Computer-Based Procedures System should be carefully evaluated in the design of a digital HSI considering the new Users Tasks Demand, the Organization of HSI Elements and the Work Environment. (author)

  16. Model for impact assessment in human factors engineering project of PWR plants with digital control

    Energy Technology Data Exchange (ETDEWEB)

    Roedel, Frederico G.; Schirru, Roberto, E-mail: froedel@nuclear.ufrj.br, E-mail: schirru@lmp.ufrj.br [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Departamento de Engenharia Nuclear

    2017-07-01

    New nuclear power plants are being designed with the digital Instrumentation and Control (I and C) as the backbone for the functions of protection, control, monitoring and display and with digital Human-System Interface (HSI). In this new environment, rather than play physical control actions, the operators begin to act as decision makers and, within this context, the Human Factors Engineering (HFE) has become an integral part of the projects. As the operational experience with the use of digital I and C systems and HSI is limited since, besides the small number of applications, it is proprietary, the objective of this work is to carry out an assessment in order to identify the most relevant aspects of a digital HSI project. The proposed model is based on concepts of fuzzy logic, uses MATLAB for data processing, defines criteria for evaluation and quantification of impacts in the project and has been applied to the General Principles and the Guidelines presented in the NUREG-0700. The assessment indicated that the Guidelines for User-Interface Interaction and Management, for Information Display and for Computer-Based Procedures System should be carefully evaluated in the design of a digital HSI considering the new Users Tasks Demand, the Organization of HSI Elements and the Work Environment. (author)

  17. Migration of Older to New Digital Control Systems in Nuclear Power Plant Main Control Rooms

    Energy Technology Data Exchange (ETDEWEB)

    Kovesdi, Casey Robert [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey Clark [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-04-01

    The United States (U.S.) Department of Energy (DOE) Office of Nuclear Energy (NE) has the primary mission to advance nuclear power by resolving socio-technical issues through research and development (R&D). One DOE-NE activity supporting this mission is the Light Water Reactor Sustainability (LWRS) program. LWRS has the overall objective to sustain the operation of existing commercial nuclear power plants (NPPs) through conducting R&D across multiple “pathways,” or R&D focus areas. The Advanced Instrumentation, Information, and Control (II&C) Systems Technologies pathway conducts targeted R&D to address aging and reliability concerns with the legacy instrumentation and control (I&C) and related information systems in operating U.S. NPPs. This work involves (1) ensuring that legacy analog II&C systems are not life-limiting issues for the LWR fleet, and (2) implementing digital II&C technology in a manner that enables broad innovation and business improvement in the NPP operating model. Under the LWRS Advanced II&C pathway, Human Factors experts at Idaho National Laboratory (INL) have been conducting R&D in support of NPP main control room (MCR) modernization activities. Work in prior years has focused on migrating analog I&C systems to new digital I&C systems (). In fiscal year 2016 (FY16), one new focus area for this research is migrating older digital I&C systems to new and advanced digital I&C systems. This report summarizes a plan for conducting a digital-to-digital migration of a legacy digital I&C system to a new digital I&C system in support of control room modernization activities.

  18. Migration of Older to New Digital Control Systems in Nuclear Power Plant Main Control Rooms

    International Nuclear Information System (INIS)

    Kovesdi, Casey Robert; Joe, Jeffrey Clark

    2016-01-01

    The United States (U.S.) Department of Energy (DOE) Office of Nuclear Energy (NE) has the primary mission to advance nuclear power by resolving socio-technical issues through research and development (R&D). One DOE-NE activity supporting this mission is the Light Water Reactor Sustainability (LWRS) program. LWRS has the overall objective to sustain the operation of existing commercial nuclear power plants (NPPs) through conducting R&D across multiple ''pathways,'' or R&D focus areas. The Advanced Instrumentation, Information, and Control (II&C) Systems Technologies pathway conducts targeted R&D to address aging and reliability concerns with the legacy instrumentation and control (I&C) and related information systems in operating U.S. NPPs. This work involves (1) ensuring that legacy analog II&C systems are not life-limiting issues for the LWR fleet, and (2) implementing digital II&C technology in a manner that enables broad innovation and business improvement in the NPP operating model. Under the LWRS Advanced II&C pathway, Human Factors experts at Idaho National Laboratory (INL) have been conducting R&D in support of NPP main control room (MCR) modernization activities. Work in prior years has focused on migrating analog I&C systems to new digital I&C systems (). In fiscal year 2016 (FY16), one new focus area for this research is migrating older digital I&C systems to new and advanced digital I&C systems. This report summarizes a plan for conducting a digital-to-digital migration of a legacy digital I&C system to a new digital I&C system in support of control room modernization activities.

  19. Digital Sensor Technology

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Ken D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Quinn, Edward L. [Technology Resources, Dana Point, CA (United States); Mauck, Jerry L. [Technology Resources, Dana Point, CA (United States); Bockhorst, Richard M. [Technology Resources, Dana Point, CA (United States)

    2015-02-01

    The nuclear industry has been slow to incorporate digital sensor technology into nuclear plant designs due to concerns with digital qualification issues. However, the benefits of digital sensor technology for nuclear plant instrumentation are substantial in terms of accuracy and reliability. This paper, which refers to a final report issued in 2013, demonstrates these benefits in direct comparisons of digital and analog sensor applications. Improved accuracy results from the superior operating characteristics of digital sensors. These include improvements in sensor accuracy and drift and other related parameters which reduce total loop uncertainty and thereby increase safety and operating margins. An example instrument loop uncertainty calculation for a pressure sensor application is presented to illustrate these improvements. This is a side-by-side comparison of the instrument loop uncertainty for both an analog and a digital sensor in the same pressure measurement application. Similarly, improved sensor reliability is illustrated with a sample calculation for determining the probability of failure on demand, an industry standard reliability measure. This looks at equivalent analog and digital temperature sensors to draw the comparison. The results confirm substantial reliability improvement with the digital sensor, due in large part to ability to continuously monitor the health of a digital sensor such that problems can be immediately identified and corrected. This greatly reduces the likelihood of a latent failure condition of the sensor at the time of a design basis event. Notwithstanding the benefits of digital sensors, there are certain qualification issues that are inherent with digital technology and these are described in the report. One major qualification impediment for digital sensor implementation is software common cause failure (SCCF).

  20. Progress of nuclear safety for symbiosis and sustainability advanced digital instrumentation, control and information systems for nuclear power plants

    CERN Document Server

    Yoshikawa, Hidekazu

    2014-01-01

    This book introduces advanced methods of computational and information systems allowing readers to better understand the state-of-the-art design and implementation technology needed to maintain and enhance the safe operation of nuclear power plants. The subjects dealt with in the book are (i) Full digital instrumentation and control systems and human?machine interface technologies (ii) Risk? monitoring methods for large and? complex? plants (iii) Condition monitors for plant components (iv) Virtual and augmented reality for nuclear power plants and (v) Software reliability verification and val

  1. Technical study of real-time simulation system for digital I and C system of steam generator in nuclear power plant

    International Nuclear Information System (INIS)

    Shi Ji; Jiang Mingyu; Ma Yunqin

    2004-01-01

    The real-time simulation system, which forms a interactive closed circle together with the steam generator control system, has been developed using a dynamic mathematical model of steam generator in this paper. It can provide a simulation target for upgrades of digital Instrument and Control system in Nuclear Power Plant (NPP) and is applicable for further research of control schemes. With this program, the authors have studied and analyzed the response of transient parameters to some different disturbance, the calculated results are in good agreement with those calculated by NPP simulator program. This will give a theoretical analysis for upgrades of digital I and C system in nuclear power plant

  2. Cyber Threat and vulnerability Analysis for Digital Assets of NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Eun Se; Seo, In Yong [Korea Electric Power research Institute, Daejeon (Korea, Republic of); Kim, See Hong [Korea Hydro and Nuclear Power Co., Seoul (Korea, Republic of)

    2009-10-15

    Today's computer and communication technology breakthrough make increase plant floor replacement from analog instrumentation and control systems of nuclear power plants to a full-fledged digital system . The rich functionality and crisp accuracy are one of big advantages of digital technology adaptation, but use of open networks and inherited shared system resources (memory, network, etc.) are well known weak points of digital system. Intended or un-intended cyber attack throughout power plant digital control system's weak point may result to wide area of system failures and that easily defeats system operation and multiple protection safeguards. Well organized cyber security analysis for nuclear plant digital control systems (digital assets) are required.

  3. Integration technique of digital I and C replacement and its Critical Digital Review procedure

    International Nuclear Information System (INIS)

    Huang, Hui-Wen; Yang, Wen-Long

    2013-01-01

    Highlights: ► A digital I and C replacement integration technique have been developed. ► Establishment of Nuclear Power Plant Digital Replacement Integration Guideline. ► Preliminary Investigation on I and C System Digitalization. ► Evaluation on I and C System Digitalization. ► Establishment of I and C System Digitalization Architectures. -- Abstract: Institute of Nuclear Energy Research (INER) developed a digital Instrumentation and Control (I and C) replacement integration technique on the basis of requirement of the three existing nuclear power plants (NPPs), which are Chin–Shan (CS) NPP, Kuo–Sheng (KS) NPP, and Maanshan (MS) NPP, in Taiwan, and also developed the related Critical Digital Review (CDR) procedure. The digital I and C replacement integration technique includes: (1) Establishment of Nuclear Power Plant Digital Replacement Integration Guideline, (2) Preliminary Investigation on I and C System Digitalization, (3) Evaluation on I and C System Digitalization, and (4) Establishment of I and C System Digitalization Architectures. These works can be a reference for performing I and C system digital replacement integration of the three existing NPPs of Taiwan Power Company (TPC). A CDR is the review for a critical system digital I and C replacement. The major reference of this procedure is EPRI TR-1011710 (2005) “Handbook for Evaluating Critical Digital Equipment and Systems” which was published by the Electric Power Research Institute (EPRI). With this document, INER developed a TPC-specific CDR procedure. Currently, CDR becomes one of the policies for digital I and C replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The CDR review items include the comparison of the design change, Software Verification and Validation (SV and V), Failure Mode and Effects Analysis (FMEA), Evaluation of Diversity and Defense-in-depth (D3), Evaluation of

  4. LEITTEC '96. Digitization of instrumentation and control in nuclear power plants

    International Nuclear Information System (INIS)

    Bauer, K.G.

    1997-01-01

    The nuclear power plants in operation in Germany have been commissioned in the years from 1968 until 1988. Their control and safety systems likewise correspond to the electronic technology available then, as e.g. discrete semi-conductor technology. The high reliability of those systems contributed a major share to the excellent operating results achieved by German nuclear power plants. However, aging of existing systems as well as spare part availability and integration of older and more recent hardware generations now are posing specific problems. Intensive work has been devoted to the retrofitting of existing systems and integration of computer-assisted control systems as well as conversion to programmable systems in order to achieve a basis permitting economically justifiable operation, acceptable also from the angle of hardware and software inspection requirements, so that the German Atomforum thought that these activities and the underlying problems would make a suitable topic for a conference. There were about 150 experts attending the one-day meeting for intensive discussion and exchange of information. The proceedings volume contains 11 of the conference papers and provides an overview of the current status and expected developments in the field of digitization of instrumentation and control in nuclear power plants.(orig./CB) [de

  5. Advanced Reactor Licensing: Experience with Digital I and C Technology in Evolutionary Plants

    International Nuclear Information System (INIS)

    Wood, RT

    2004-01-01

    This report presents the findings from a study of experience with digital instrumentation and controls (I and C) technology in evolutionary nuclear power plants. In particular, this study evaluated regulatory approaches employed by the international nuclear power community for licensing advanced l and C systems and identified lessons learned. The report (1) gives an overview of the modern l and C technologies employed at numerous evolutionary nuclear power plants, (2) identifies performance experience derived from those applications, (3) discusses regulatory processes employed and issues that have arisen, (4) captures lessons learned from performance and regulatory experience, (5) suggests anticipated issues that may arise from international near-term deployment of reactor concepts, and (6) offers conclusions and recommendations for potential activities to support advanced reactor licensing in the United States

  6. Fault tolerant digital control systems for boiling water reactors

    International Nuclear Information System (INIS)

    Chakraborty, S.; Cash, N.R.

    1986-01-01

    In a Boiling Water Reactor nuclear power plant, the power generation control function is divided into several systems, each system controlling only a part of the total plant. Presently, each system is controlled by conventional analog or digital logic circuits with little interaction for coordinated control. The advent of microprocessors has allowed the development of distributed fault-tolerant digital controls. The objective is to replace these conventional controls with fault-tolerant digital controls connected together with digital communication links to form a fully integrated nuclear power plant control system

  7. Digital System Categorization Methodology to Support Integration of Digital Instrumentation and Control Models into PRAs

    International Nuclear Information System (INIS)

    Arndt, Steven A.

    2011-01-01

    It has been suggested that by categorizing the various digital systems used in safety critical applications in nuclear power plants, it would be possible to determine which systems should be modeled in the analysis of the larger plant wide PRA, at what level of detail the digital system should be modeled and using which methods. The research reported in this paper develops a categorization method using system attributes to permit a modeler to more effectively model the systems that will likely have the most critical contributions to the overall plant safety and to more effectively model system interactions for those digital systems where the interactions are most important to the overall accuracy and completeness of the plant PRA. The proposed methodology will categorize digital systems based on certain attributes of the systems themselves and how they will be used in the specific application. This will help determine what digital systems need to be modeled and at what level of detail, and can be used to guide PRA analysis and regulatory reviews. The three-attribute categorization strategy that was proposed by Arndt is used as the basis for the categorization methodology developed here. The first attribute, digital system complexity, is based on Type Il interactions defined by Aldemir and an overall digital system size and complexity index. The size and complexity index used are previously defined software complexity metrics. Potential sub-attributes of digital system complexity include, design complexity, software complexity, hardware complexity, system function complexity and testability. The second attribute, digital system interactions/inter-conductivity, is a combination of Rushby's coupling and Ademir's Type I interactions. Digital systems that are loosely coupled and/or have very few Type I interaction would not interact dynamically with the overall system and would have a low interactions/inter-conductivity score. Potential sub-attributes of digital system

  8. Digital System Categorization Methodology to Support Integration of Digital Instrumentation and Control Models into PRAs

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, Steven A. [U.S. Nuclear Regulatory Commission, Washington D.C. (United States)

    2011-08-15

    It has been suggested that by categorizing the various digital systems used in safety critical applications in nuclear power plants, it would be possible to determine which systems should be modeled in the analysis of the larger plant wide PRA, at what level of detail the digital system should be modeled and using which methods. The research reported in this paper develops a categorization method using system attributes to permit a modeler to more effectively model the systems that will likely have the most critical contributions to the overall plant safety and to more effectively model system interactions for those digital systems where the interactions are most important to the overall accuracy and completeness of the plant PRA. The proposed methodology will categorize digital systems based on certain attributes of the systems themselves and how they will be used in the specific application. This will help determine what digital systems need to be modeled and at what level of detail, and can be used to guide PRA analysis and regulatory reviews. The three-attribute categorization strategy that was proposed by Arndt is used as the basis for the categorization methodology developed here. The first attribute, digital system complexity, is based on Type Il interactions defined by Aldemir and an overall digital system size and complexity index. The size and complexity index used are previously defined software complexity metrics. Potential sub-attributes of digital system complexity include, design complexity, software complexity, hardware complexity, system function complexity and testability. The second attribute, digital system interactions/inter-conductivity, is a combination of Rushby's coupling and Ademir's Type I interactions. Digital systems that are loosely coupled and/or have very few Type I interaction would not interact dynamically with the overall system and would have a low interactions/inter-conductivity score. Potential sub-attributes of

  9. UTILIZACIÓN DEL SUBPRODUCTO DE FIQUE: LICOR VERDE, COMO CONTROLADOR DE PLAGAS EN EL CULTIVO DE REPOLLO (Brassica oleracea DO FIQUE SUBPRODUTOS UTILIZAÇÃO: LICOR VERDE COMO UM CONTROLADOR DE PRAGAS NA CULTURA DO REPOLHO (Brassica oleracea FIQUE SUBPRODUCT UTILIZATION: GREEN LIQUOR AS A PEST CONTROL IN THE CULTURE OFCABBAGE (Brassica oleracea

    Directory of Open Access Journals (Sweden)

    JHON F. IMBACHÍ-HOYOS

    2012-06-01

    Full Text Available En el vivero forestal 'La Florida' de la Corporación Autónoma Regional del Cauca CRC, se evaluó el efecto del extracto de fique (Furcraea sp como controlador de plagas en el cultivo de repollo (Brassica oleracea. Se utilizaron cuatro tratamientos (blanco, solución extracto de fique al 30% v/v, 20% v/v, 10% v/v. Las mediciones se hicieron durante seis semanas para vigor, altura, diámetro, daño por plagas y daño por enfermedades. La aplicación fue de una vez durante las tres primeras semanas; y las tres siguientes la aplicación fue de dos por semana. Los resultados se analizaron utilizando el paquete estadístico SPSS 11.5, se realizó una ANOVA con un nivel de confianza del 95% (p = 0,05 y una prueba de Tuckey. El análisis muestra que la aplicación del extracto dos veces por semana (extracto de fique al 30% v/v, presentó el mejor control de plagas, disminuyendo la presencia de daños por las plagas: mariposa blanca (Pieris sp. palomilla (Plutella xylostella y áfidos (Brevicoryne brassicae y Myzus persicae.No viveiro floresta 'La Florida' da Corporação Autônoma Regional do Cauca (CRC se abalizou o efeito do extrato de fique (Furcraea sp como controlador de plagas no cultivo de repolho (Brassica oleracea. Utilizarão- se quatro tratamentos (Branco, solução extrato de fique a 30% v/v, 20% v/v e 10% v/v. As medições fizeram-se durante seis semanas para vigor, altura, diâmetro, dano por pragas y dano por enfermidades. A aplicação foi de uma vez durante as três primeiras semanas; y as três seguintes a aplicação foi de duas por semanas. Os resultados analisaram-se utilizando o paquete estadístico SPSS 11.5, realizaram-se uma ANOVA com um nível de confiança dos 95% (p = 0,05 e uma proba de Tuckey. A análise mostra que a aplicação do extrato duas vezes por semana (extrato de fique a 30% v/v, apresentou o melhor controle de pragas reduzindo a presencia de danos por as pragas: Borboleta branca (Pieris sp, mariposa (Plutella

  10. Applying Human Factors Evaluation and Design Guidance to a Nuclear Power Plant Digital Control System

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Ulrich; Ronald Boring; William Phoenix; Emily Dehority; Tim Whiting; Jonathan Morrell; Rhett Backstrom

    2012-08-01

    The United States (U.S.) nuclear industry, like similar process control industries, has moved toward upgrading its control rooms. The upgraded control rooms typically feature digital control system (DCS) displays embedded in the panels. These displays gather information from the system and represent that information on a single display surface. In this manner, the DCS combines many previously separate analog indicators and controls into a single digital display, whereby the operators can toggle between multiple windows to monitor and control different aspects of the plant. The design of the DCS depends on the function of the system it monitors, but revolves around presenting the information most germane to an operator at any point in time. DCSs require a carefully designed human system interface. This report centers on redesigning existing DCS displays for an example chemical volume control system (CVCS) at a U.S. nuclear power plant. The crucial nature of the CVCS, which controls coolant levels and boration in the primary system, requires a thorough human factors evaluation of its supporting DCS. The initial digital controls being developed for the DCSs tend to directly mimic the former analog controls. There are, however, unique operator interactions with a digital vs. analog interface, and the differences have not always been carefully factored in the translation of an analog interface to a replacement DCS. To ensure safety, efficiency, and usability of the emerging DCSs, a human factors usability evaluation was conducted on a CVCS DCS currently being used and refined at an existing U.S. nuclear power plant. Subject matter experts from process control engineering, software development, and human factors evaluated the DCS displays to document potential usability issues and propose design recommendations. The evaluation yielded 167 potential usability issues with the DCS. These issues should not be considered operator performance problems but rather opportunities

  11. Computer based plant display and digital control system of Wolsong NPP Tritium Removal Facility

    International Nuclear Information System (INIS)

    Jung, C.; Smith, B.; Tosello, G.; Grosbois, J. de; Ahn, J.

    2007-01-01

    The Wolsong Tritium Removal Facility (WTRF) is an AECL-designed, first-of-a-kind facility that removes tritium from the heavy water that is used in systems of the CANDUM reactors in operation at the Wolsong Nuclear Power Plant in South Korea. The Plant Display and Control System (PDCS) provides digital plant monitoring and control for the WTRF and offers the advantages of state-of-the-art digital control system technologies for operations and maintenance. The overall features of the PDCS will be described and some of the specific approaches taken on the project to save construction time and costs, to reduce in-service life-cycle costs and to improve quality will be presented. The PDCS consists of two separate computer sub-systems: the Digital Control System (DCS) and the Plant Display System (PDS). The PDS provides the computer-based Human Machine Interface (HMI) for operators, and permits efficient supervisory or device level monitoring and control. A System Maintenance Console (SMC) is included in the PDS for the purpose of software and hardware configuration and on-line maintenance. A Historical Data System (HDS) is also included in the PDS as a data-server that continuously captures and logs process data and events for long-term storage and on-demand selective retrieval. The PDCS of WTRF has been designed and implemented based on an off-the-self PDS/DCS product combination, the Delta-V System from Emerson. The design includes fully redundant Ethernet network communications, controllers, power supplies and redundancy on selected I/O modules. The DCS provides field bus communications to interface with 3rd party controllers supplied on specialized skids, and supports HART communication with field transmitters. The DCS control logic was configured using a modular and graphical approach. The control strategies are primarily device control modules implemented as autonomous control loops, and implemented using IEC 61131-3 Function Block Diagram (FBD) and Structured

  12. Defense-in-depth and diversity evaluation to cope with design bases events concurrent with common mode failure in digital plant protection system for KNGR

    International Nuclear Information System (INIS)

    Shin, Lee Cheol; Park, Chan Eok; Jin, Choi Chul; Tae, Seo Jong

    2001-01-01

    The Korean Next Generation Reactor (KNGR) has been evolved to adopt an advanced design feature, a digital Plant Protection System (PPS) as an effort of enhancing reliability and safety of the plant. Although the digital PPS can be designed with high reliability, it is considered to be vulnerable to the Common Mode Failure (CMF) in the system software resulting in a total loss of the built-in hardware redundancy. Therefore, a comprehensive evaluation has been performed to demonstrate the intrinsic capability of the KNGR design in coping with the design basis events concurrent with CMF in the digital PPS. Instead of the conservative bounding analysis methodology, a best-estimate analysis methodology has been developed and utilized since the design basis events accompanied by CMF in the digital PPS are categorized as beyond design bases events. A variety of diverse means such as Alternate Protection System (APS), process control systems, and timely operator actions have been verified to be effective in mitigating the design basis events with CMF in the digital PPS

  13. Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

    International Nuclear Information System (INIS)

    Miller, M.H.

    1995-01-01

    The existing Reactor Protection Systems (RPSs) at most US PWRs are systems which reflect 25 to 30 year-old designs, components and manufacturing techniques. Technological improvements, especially in relation to modern digital systems, offer improvements in functionality, performance, and reliability, as well as reductions in maintenance and operational burden. The Nuclear power industry and the US nuclear regulators are poised to move forward with the issues that have slowed the transition to modern digital replacements for nuclear power plant safety systems. The electric utility industry is now more than ever being driven by cost versus benefit decisions. Properly designed, engineered, and installed digital systems can provide adequate cost-benefit and allow continued nuclear generated electricity. This paper describes various issues and areas related to an ongoing RPS replacement demonstration project which are pertinant for a typical US nuclear plant to consider cost-effective replacement of an aging analog RPS with a modern digital RPS. The following subject areas relative to the Oconee Nuclear Station ISAT trademark Demonstrator project are discussed: Operator Interface Development; Equipment Qualification; Validation and Verification of Software; Factory Testing; Field Changes and Verification Testing; Utility Operational, Engineering and Maintenance; Experiences with Demonstration System; and Ability to operate in parallel with the existing Analog RPS

  14. Engineering development of a digital replacement protection system at an operating US PWR nuclear power plant: Installation and operational experiences

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.H. [Duke Power Co., Seneca, SC (United States)

    1995-04-01

    The existing Reactor Protection Systems (RPSs) at most US PWRs are systems which reflect 25 to 30 year-old designs, components and manufacturing techniques. Technological improvements, especially in relation to modern digital systems, offer improvements in functionality, performance, and reliability, as well as reductions in maintenance and operational burden. The Nuclear power industry and the US nuclear regulators are poised to move forward with the issues that have slowed the transition to modern digital replacements for nuclear power plant safety systems. The electric utility industry is now more than ever being driven by cost versus benefit decisions. Properly designed, engineered, and installed digital systems can provide adequate cost-benefit and allow continued nuclear generated electricity. This paper describes various issues and areas related to an ongoing RPS replacement demonstration project which are pertinant for a typical US nuclear plant to consider cost-effective replacement of an aging analog RPS with a modern digital RPS. The following subject areas relative to the Oconee Nuclear Station ISAT{trademark} Demonstrator project are discussed: Operator Interface Development; Equipment Qualification; Validation and Verification of Software; Factory Testing; Field Changes and Verification Testing; Utility Operational, Engineering and Maintenance; Experiences with Demonstration System; and Ability to operate in parallel with the existing Analog RPS.

  15. Implementation digital technologies in nuclear utilities

    Energy Technology Data Exchange (ETDEWEB)

    Wiegand, C.; Maselli, A.J., E-mail: Tony.Maselli@Invensys.com [Invensys Operations Management, London (United Kingdom)

    2012-07-01

    The introduction of digital technologies into the nuclear industry has assisted in many ways and made many of the Life Extensions and Uprates a possibility. But with this introduction of digital technologies comes some potentially challenging issues which need to be addressed for ultimate project success. This presentation discusses what a nuclear utility should consider and establish when implementing digital technologies in their plant. Digital technologies have been employed in many safety critical industries such as Aerospace, Pharmaceutical, Oil and Gas, and Chemical. However, nuclear industry implementation of digital technologies has been slow and in many ways tenuous. There are even documented operating experience events in which plant trips/SCRAMs occurred during a digital system implementation. This presentation aims to prevent those issues drawing upon the lessons learned over the past 5 years. Considerations include general challenges to overcome when implementing Digital Technologies, how to justify and execute projects, evaluation of resource knowledge, and the new challenges of Cyber Security. (author)

  16. Implementation digital technologies in nuclear utilities

    International Nuclear Information System (INIS)

    Wiegand, C.; Maselli, A.J.

    2012-01-01

    The introduction of digital technologies into the nuclear industry has assisted in many ways and made many of the Life Extensions and Uprates a possibility. But with this introduction of digital technologies comes some potentially challenging issues which need to be addressed for ultimate project success. This presentation discusses what a nuclear utility should consider and establish when implementing digital technologies in their plant. Digital technologies have been employed in many safety critical industries such as Aerospace, Pharmaceutical, Oil and Gas, and Chemical. However, nuclear industry implementation of digital technologies has been slow and in many ways tenuous. There are even documented operating experience events in which plant trips/SCRAMs occurred during a digital system implementation. This presentation aims to prevent those issues drawing upon the lessons learned over the past 5 years. Considerations include general challenges to overcome when implementing Digital Technologies, how to justify and execute projects, evaluation of resource knowledge, and the new challenges of Cyber Security. (author)

  17. Development Methodology of a Cyber Security Risk Analysis and Assessment Tool for Digital I and C Systems in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Cha, K. H.; Lee, C. K.; Song, J. G.; Lee, Y. J.; Kim, J. Y.; Lee, J. W.; Lee, D. Y.

    2011-01-01

    With the use of digital computers and communication networks the hot issues on cyber security were raised about 10 years ago. The scope of cyber security application has now been extended from the safety Instrumentation and Control (I and C) system to safety important systems, plant security system, and emergency preparedness system. Therefore, cyber security should be assessed and managed systematically throughout the development life cycle of I and C systems in order for their digital assets to be protected from cyber attacks. Fig. 1 shows the concept of a cyber security risk management of digital I and C systems in nuclear power plants (NPPs). A lot of cyber security risk assessment methods, techniques, and supported tools have been developed for Information Technology (IT) systems, but they have not been utilized widely for cyber security risk assessments of the digital I and C systems in NPPs. The main reason is a difference in goals between IT systems and nuclear I and C systems. Confidentiality is important in IT systems, but availability and integrity are important in nuclear I and C systems. Last year, it was started to develop a software tool to be specialized for the development process of nuclear I and C systems. This paper presents a development methodology of the Cyber Security Risk analysis and Assessment Tool (CSRAT) for the digital I and C systems in NPP

  18. Development Methodology of a Cyber Security Risk Analysis and Assessment Tool for Digital I and C Systems in Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Cha, K. H.; Lee, C. K.; Song, J. G.; Lee, Y. J.; Kim, J. Y.; Lee, J. W.; Lee, D. Y. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    With the use of digital computers and communication networks the hot issues on cyber security were raised about 10 years ago. The scope of cyber security application has now been extended from the safety Instrumentation and Control (I and C) system to safety important systems, plant security system, and emergency preparedness system. Therefore, cyber security should be assessed and managed systematically throughout the development life cycle of I and C systems in order for their digital assets to be protected from cyber attacks. Fig. 1 shows the concept of a cyber security risk management of digital I and C systems in nuclear power plants (NPPs). A lot of cyber security risk assessment methods, techniques, and supported tools have been developed for Information Technology (IT) systems, but they have not been utilized widely for cyber security risk assessments of the digital I and C systems in NPPs. The main reason is a difference in goals between IT systems and nuclear I and C systems. Confidentiality is important in IT systems, but availability and integrity are important in nuclear I and C systems. Last year, it was started to develop a software tool to be specialized for the development process of nuclear I and C systems. This paper presents a development methodology of the Cyber Security Risk analysis and Assessment Tool (CSRAT) for the digital I and C systems in NPP

  19. Light Water Reactor Sustainability Program. Digital Architecture Requirements

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Kenneth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    The Digital Architecture effort is a part of the Department of Energy (DOE) sponsored Light-Water Reactor Sustainability (LWRS) Program conducted at Idaho National Laboratory (INL). The LWRS program is performed in close collaboration with industry research and development (R&D) programs that provides the technical foundations for licensing and managing the long-term, safe, and economical operation of current nuclear power plants (NPPs). One of the primary missions of the LWRS program is to help the U.S. nuclear industry adopt new technologies and engineering solutions that facilitate the continued safe operation of the plants and extension of the current operating licenses. Therefore, a major objective of the LWRS program is the development of a seamless digital environment for plant operations and support by integrating information from plant systems with plant processes for nuclear workers through an array of interconnected technologies. In order to get the most benefits of the advanced technology suggested by the different research activities in the LWRS program, the nuclear utilities need a digital architecture in place to support the technology. A digital architecture can be defined as a collection of information technology (IT) capabilities needed to support and integrate a wide-spectrum of real-time digital capabilities for nuclear power plant performance improvements. It is not hard to imagine that many processes within the plant can be largely improved from both a system and human performance perspective by utilizing a plant wide (or near plant wide) wireless network. For example, a plant wide wireless network allows for real time plant status information to easily be accessed in the control room, field workers’ computer-based procedures can be updated based on the real time plant status, and status on ongoing procedures can be incorporated into smart schedules in the outage command center to allow for more accurate planning of critical tasks. The goal

  20. Advanced digital I and C technology in nuclear power plants. A success story from Finland and China

    International Nuclear Information System (INIS)

    Liebschner, T.; Heidowitzsch, B.

    2005-01-01

    FRAMATOME ANP together with Siemens PGL have just commissioned the I and C systems for the Chinese Nuclear Power Plant Tianwan Unit 1, design the I and C systems for the first European Pressurized Water Reactor Olkiluoto 3 in Finland and started one of the most extensive and ambitious modernization project in a nuclear power plant for Loviisa NPP in Finland. The presentation delivers an insight into the problematic of digital I and C systems integration and focuses on aspects regarding design criteria, Structure and test approaches. (author)

  1. Simulation of Digital Control Computer of Nuclear Power Plant Based on Virtual Machine Technology

    International Nuclear Information System (INIS)

    Hou, Xue Yan; Li, Shu; Li, Qing

    2011-01-01

    Based on analyzing DCC (Digital Control Computer) instruction sets, memory map, display controllers and I/O system, virtual machine of DCC (abbr. VM DCC) has been developed. The executive and control programs, same as running on NPP (Nuclear Power Plant) unit's DCC, can run on the VM DCC smoothly and get same control results. Dual VM DCC system has been successfully applied in NPP FSS(Full Scope Simulator) training. It not only improves FSS's fidelity but also makes maintaining easier

  2. Digital I and C systems in nuclear power plants. Risk-screening of environmental stressors and a comparison of hardware unavailability with an existing analog system

    International Nuclear Information System (INIS)

    Hassan, M.; Vesely, W.E.

    1998-01-01

    In this report, we present a screening study to identify environmental stressors for digital instrumentation and control (I ampersand C) systems in a nuclear power plant (NPP) which can be potentially risk-significant, and compare the hardware unavailability of such a system with that of its existing analog counterpart. The stressors evaluated are temperature, humidity, vibration, radiation, electro-magnetic interference (EMI), and smoke. The results of risk-screening for an example plant, subject to some bounding assumptions and based on relative changes in plant risk (core damage frequency impacts of the stressors), indicate that humidity, EMI from lightning, and smoke can be potentially risk-significant. Risk from other sources of EMI could not be evaluated for a lack of data. Risk from temperature appears to be insignificant as that from the assumed levels of vibrations. A comparison of the hardware unavailability of the existing analog Safety Injection Actuation System (SIAS) in the example plant with that of an assumed digital upgrade of the system indicates that system unavailability may be more sensitive to the level of redundancy in elements of the digital system than to the environmental and operational variations involved. The findings of this study can be used to focus activities relating to the regulatory basis for digital I ampersand C upgrades in NPPs, including identification of dominant stressors, data-gathering, equipment qualification, and requirements to limit the effects of environmental stressors. 30 refs., 8 figs., 26 tabs

  3. Simulation of Digital Control Computer of Nuclear Power Plant Based on Virtual Machine Technology

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Xue Yan; Li, Shu; Li, Qing [China Nuclear Power Operation Technology Co., Wuhan (China)

    2011-08-15

    Based on analyzing DCC (Digital Control Computer) instruction sets, memory map, display controllers and I/O system, virtual machine of DCC (abbr. VM DCC) has been developed. The executive and control programs, same as running on NPP (Nuclear Power Plant) unit's DCC, can run on the VM DCC smoothly and get same control results. Dual VM DCC system has been successfully applied in NPP FSS(Full Scope Simulator) training. It not only improves FSS's fidelity but also makes maintaining easier.

  4. The virtual digital nuclear power plant: A modern tool for supporting the lifecycle of VVER-based nuclear power units

    Science.gov (United States)

    Arkadov, G. V.; Zhukavin, A. P.; Kroshilin, A. E.; Parshikov, I. A.; Solov'ev, S. L.; Shishov, A. V.

    2014-10-01

    The article describes the "Virtual Digital VVER-Based Nuclear Power Plant" computerized system comprising a totality of verified initial data (sets of input data for a model intended for describing the behavior of nuclear power plant (NPP) systems in design and emergency modes of their operation) and a unified system of new-generation computation codes intended for carrying out coordinated computation of the variety of physical processes in the reactor core and NPP equipment. Experiments with the demonstration version of the "Virtual Digital VVER-Based NPP" computerized system has shown that it is in principle possible to set up a unified system of computation codes in a common software environment for carrying out interconnected calculations of various physical phenomena at NPPs constructed according to the standard AES-2006 project. With the full-scale version of the "Virtual Digital VVER-Based NPP" computerized system put in operation, the concerned engineering, design, construction, and operating organizations will have access to all necessary information relating to the NPP power unit project throughout its entire lifecycle. The domestically developed commercial-grade software product set to operate as an independently operating application to the project will bring about additional competitive advantages in the modern market of nuclear power technologies.

  5. Digital transformation of nuclear industry, what improvement made in France and abroad?

    International Nuclear Information System (INIS)

    Roy, L.

    2017-01-01

    In Russia digital technologies have entered nuclear industry since long, they are not only an important tool for reducing costs but also a part of the cost itself as a digital twin of the plant is sold with the plant. This digital plant will be useful for operating the real plant in terms of maintenance and testing the procedures. In the United-States, nuclear energy faces the fierce competition of shale gas and some plant operators foresee to close nuclear stations in a near future but other plant operators think that digital technologies will be a major tool to cut by 30% their operating costs. A feature of the American nuclear industry is the important number of innovative start-ups, the NRC (Nuclear Regulatory Commission) has accepted to be involved as soon as the design phase of projects in order to ease the certification process and shorten schedules. Generally speaking the weight of engineering in the nuclear industry is more than twice as important as in other industries, so the use of digital tools has a more important positive impact in nuclear projects than in other sectors. In France the complete overhaul of nuclear reactors that is imposed by law every 10 years, is already largely based on digital technologies through the use of partial digital twins of the plant. (A.C.)

  6. Verification of failover effects from distributed control system communication networks in digitalized nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Min, Moon Gi; Lee, Jae Ki; Lee, Kwang Hyun; Lee, Dong Il; Lim, Hee Taek [Korea Hydro and Nuclear Power Co., Ltd, Daejeon (Korea, Republic of)

    2017-08-15

    Distributed Control System (DCS) communication networks, which use Fast Ethernet with redundant networks for the transmission of information, have been installed in digitalized nuclear power plants. Normally, failover tests are performed to verify the reliability of redundant networks during design and manufacturing phases; however, systematic integrity tests of DCS networks cannot be fully performed during these phases because all relevant equipment is not installed completely during these two phases. In additions, practical verification tests are insufficient, and there is a need to test the actual failover function of DCS redundant networks in the target environment. The purpose of this study is to verify that the failover functions works correctly in certain abnormal conditions during installation and commissioning phase and identify the influence of network failover on the entire DCS. To quantify the effects of network failover in the DCS, the packets (Protocol Data Units) must be collected and resource usage of the system has to be monitored and analyzed. This study introduces the use of a new methodology for verification of DCS network failover during the installation and commissioning phases. This study is expected to provide insight into verification methodology and the failover effects from DCS redundant networks. It also provides test results of network performance from DCS network failover in digitalized domestic nuclear power plants (NPPs)

  7. Human factors issues in digital system design and implementation

    International Nuclear Information System (INIS)

    Galletti, Greg S.

    1998-01-01

    A goal of the U.S. Nuclear Regulatory Commission (NRC) is to ensure safety in the application of digital equipment upgrades to nuclear power plant control rooms and local control stations. One of the areas of specific interest is the integration of digital technology into existing analog control, display, and information systems and the implications of such integration for operators in regard to their use of this new equipment to safely operate the plant. This paper is a discussion of human performance issues related to the introduction of such digital equipment into operating nuclear power plants. (author)

  8. Convertidor buck-boost controlado digitalmente con histeresis cero mediante un dsp; Back-Booost Converter digitally controlled by zero hysteresis method, using DSP

    Directory of Open Access Journals (Sweden)

    Fredy Edimer Hoyos Velasco

    2011-02-01

    Full Text Available En este trabajo se estudia el comportamiento de un convertidor electrónico en configuración buck-boost. Elobjetivo del controlador es hacer el rastreo de señales sinusoidales usando un controlador con histéresiscero, es decir que el usuario pueda tener a la salida cualquier señal a un nivel más alto de potencia y conla característica que esta señal deseada es regulada variable en frecuencia, en amplitud y forma de onda.El controlador es rápido pues se comprobó en el laboratorio que ante perturbaciones en la carga y en laseñal de referencia, se comporta adecuadamente. Se implementó el convertidor usando un inversormonofásico en configuración de medio puente y se controla el sistema con un prototipo rápido de control(RCP DS1104 en tiempo real. In this work, we analysed the behaviour of a buck-boost electronic converter. The objective of the zerohysteresis controller is to track user defined sinusoidal signals, usually featuring high power level andvariable frequency, amplitude and wave form. The controller was implemented in the laboratory, whereload and reference signal disturbances were introduced. The controller achieved a fast and adequatebehaviour. The converter was implemented using a half bridge monophasic inverter, and a rapid controlprototyping (RCP DS1104 in real time for the control task.

  9. Effect Analysis of Faults in Digital I and C Systems of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Jun; Jung, Won Dea [KAERI, Dajeon (Korea, Republic of); Kim, Man Cheol [Chung-Ang University, Seoul (Korea, Republic of)

    2014-08-15

    A reliability analysis of digital instrumentation and control (I and C) systems in nuclear power plants has been introduced as one of the important elements of a probabilistic safety assessment because of the unique characteristics of digital I and C systems. Digital I and C systems have various features distinguishable from those of analog I and C systems such as software and fault-tolerant techniques. In this work, the faults in a digital I and C system were analyzed and a model for representing the effects of the faults was developed. First, the effects of the faults in a system were analyzed using fault injection experiments. A software-implemented fault injection technique in which faults can be injected into the memory was used based on the assumption that all faults in a system are reflected in the faults in the memory. In the experiments, the effect of a fault on the system output was observed. In addition, the success or failure in detecting the fault by fault-tolerant functions included in the system was identified. Second, a fault tree model for representing that a fault is propagated to the system output was developed. With the model, it can be identified how a fault is propagated to the output or why a fault is not detected by fault-tolerant techniques. Based on the analysis results of the proposed method, it is possible to not only evaluate the system reliability but also identify weak points of fault-tolerant techniques by identifying undetected faults. The results can be reflected in the designs to improve the capability of fault-tolerant techniques.

  10. Effect analysis of faults in digital I and C systems of nuclear power plants

    International Nuclear Information System (INIS)

    Lee, Seung Jun

    2014-01-01

    A reliability analysis of digital instrumentation and control (I and C) systems in nuclear power plants has been introduced as one of the important elements of a probabilistic safety assessment because of the unique characteristics of digital I and C systems. Digital I and C systems have various features distinguishable from those of analog I and C systems such as software and fault-tolerant techniques. In this work, the faults in a digital I and C system were analyzed and a model for representing the effects of the faults was developed. First, the effects of the faults in a system were analyzed using fault injection experiments. A software-implemented fault injection technique in which faults can be injected into the memory was used based on the assumption that all faults in a system are reflected in the faults in the memory. In the experiments, the effect of a fault on the system output was observed. In addition, the success or failure in detecting the fault by fault-tolerant functions included in the system was identified. Second, a fault tree model for representing that a fault is propagated to the system output was developed. With the model, it can be identified how a fault is propagated to the output or why a fault is not detected by fault-tolerant techniques. Based on the analysis results of the proposed method, it is possible to not only evaluate the system reliability but also identify weak points of fault-tolerant techniques by identifying undetected faults. The results can be reflected in the designs to improve the capability of fault-tolerant techniques. (author)

  11. How digital revolution has an impact on maintenance

    International Nuclear Information System (INIS)

    Thevenon, J.B.

    2017-01-01

    Digital technologies can manage a huge quantity of data from a variety of sensors which draws an accurate picture of the real state of a component or even a complete plant. Combined with predictive models, the knowledge of the real state of a component can lead to predictive maintenance in which components are repaired or replaced before they fail. EDF takes the opportunity of the ten-yearly outage of a plant to draw a digital twin of this plant with the help of 3-dimensional photography and laser scans. This digital twin will be used to visualize and validate any change or maintenance operation. The digital twin will be also useful to communicate efficiently with sub-contractors and visualize the work to be done. In the future, new applications will be added to the twin and for instance the level of contamination could be implemented in order to increase safety for maintenance operations. Needless to say that a digital twin will be very useful for the dismantling of the installation. (A.C.)

  12. Development of Risk Assessment Technology for Low Power, Shutdown and Digital I and C Systems

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Seung Cheol; Kang, Hyung Gook; Lim, Ho Gon; Park, Jin Hee; Eom, Heung Sub; Kim, Tae Woon; Ha, Jae Joo

    2005-04-15

    There are two technical areas to deal with in the project; the low power and shutdown probabilistic safety assessment (PSA), and the digital I and C PSA. The scope and contents of each area could be summarized as follows: Quality assessment of a LPSD PSA model for a Korean Standard Nuclear Power Plant (KSNP), Quality improvement of the KSNP LPSD PSA model in the following four technical areas; plant operating status (POS), initiating event analysis, determination of success criteria, accident sequence analysis, Development of the LPSD risk management technologies, Unavailability analysis of Digital safety systems such as Digital Plant Protection System (DPPS) and Digital Engineered Safety Feature Actuation System (DESFAS), Impact analysis of the digital safety systems on plant risks throughout of the digital plant risk models for evaluating core damage frequency (CDF) and large early release frequency (LERF), Study on the methodologies for treating digital-specific problems in the digital I and C PSA such as reliability of safety-critical software, common cause failure (CCF) of digital components, fault coverage, etc.

  13. Development of Risk Assessment Technology for Low Power, Shutdown and Digital I and C Systems

    International Nuclear Information System (INIS)

    Jang, Seung Cheol; Kang, Hyung Gook; Lim, Ho Gon; Park, Jin Hee; Eom, Heung Sub; Kim, Tae Woon; Ha, Jae Joo

    2005-04-01

    There are two technical areas to deal with in the project; the low power and shutdown probabilistic safety assessment (PSA), and the digital I and C PSA. The scope and contents of each area could be summarized as follows: Quality assessment of a LPSD PSA model for a Korean Standard Nuclear Power Plant (KSNP), Quality improvement of the KSNP LPSD PSA model in the following four technical areas; plant operating status (POS), initiating event analysis, determination of success criteria, accident sequence analysis, Development of the LPSD risk management technologies, Unavailability analysis of Digital safety systems such as Digital Plant Protection System (DPPS) and Digital Engineered Safety Feature Actuation System (DESFAS), Impact analysis of the digital safety systems on plant risks throughout of the digital plant risk models for evaluating core damage frequency (CDF) and large early release frequency (LERF), Study on the methodologies for treating digital-specific problems in the digital I and C PSA such as reliability of safety-critical software, common cause failure (CCF) of digital components, fault coverage, etc

  14. Digital Image Quantitative Evaluations for Low Cost Film Digitizers Height Determination

    International Nuclear Information System (INIS)

    Khairul Anuar Mohd Salleh; Arshad Yassin; Ahmad Nasir Yusof; Noorhazleena Azaman

    2016-01-01

    Non Destructive Testing (NDT) technology contributes significant improvement to the quality of industrial products, and the integrity of equipment and plants. Introduction of powerful computers and reliable imaging technology has had significant impact on the traditional nuclear based NDT technology. Demand for faster, reliable, low cost, and flexible technology is rapidly increased. With the growing demand for more efficient digital archiving, digital image analysis, and reporting results with a low cost technology, one cannot deny the importance of having another cheaper solution. This project will apply fundamental principle of image digitization to be used in building up a low cost film digitization solution. The height of the film digitization was carefully determined by examining each digital images produced. Three (3) repetitive quantitative evaluations (Modulation Transfer Function [MTF], Characteristic Transfer Curve [CTC], and Contrast to Noise Ratio [CNR]) were performed at different condition to assist with the determination of the low cost film digitizers height. All 3 evaluations were successfully applied and the most appropriate height was successfully determined. (author)

  15. IAEA technical meeting on integrating analog and digital instrumentation and control systems in hybrid main control rooms at nuclear power plants. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The majority of instrumentation and control (I and C) equipment in nuclear power plants in the world was designed 30 to over 45 years ago with analog and relay components, and in some cases rudimentary digital technology. Today, most of these plants continue to operate with a substantial amount of this original I and C equipment that is or soon will be obsolete. Much of this equipment is approaching or exceeding its life expectancy, resulting in increasing maintenance efforts to sustain acceptable system performance. Decreasing availability of replacement parts, and the accelerating deterioration of the infrastructure of manufacturers that support analog technology, accentuate the obsolescence problems and cause operation and maintenance (O and M) cost increases. Refurbishments and license extensions mean that a plant must be supported longer, which will increase the obsolescence issues. In addition, the older technology limits the possibilities for adding new beneficial capabilities to the plant systems and interfaces. New technology provides the opportunity to improve plant performance, human system interface (HSI) functionality, and reliability; to enhance operator performance and reliability, and to address difficulties in finding young professionals with education and experience with older analog technology. Finally, there may be changes in regulatory requirements that could necessitate modernization activities. Modernization of I and C systems and components, using digital equipment to address these obsolescence issues and the need to improve plant performance (e.g., increase power output capacity, reliability, and availability) while maintaining high levels of safety, is a current major issue for nuclear power plants throughout the world. A number of nuclear power utilities are committing to major modernization programs. The need for this modernization will accelerate as plants age, obsolescence issues increase, plants receive license renewals, and features

  16. Uma contribuição pedagógica acerca da criação e utilização dos objetos de aprendizagem na capacitação do controlador de tráfego aéreo

    OpenAIRE

    Elaine Pires de Abreu

    2014-01-01

    Este trabalho trata do uso de objetos de aprendizagem (OA) na formação e treinamento continuado de controladores de tráfego aéreo. A capacitação das pessoas que trabalham no controle de tráfego aéreo é um importante fator de segurança operacional. Partindo das teorias de aprendizagem de adultos, colaborativa, significativa e multimídia, a pesquisa toma como referência as metodologias LODAS e ISD-ADDIE para propor um método inovador de desenvolvimento e utilização de OA para uso na formação e ...

  17. Design of coordinated controller in nuclear power plant based on digital instrument and control technology

    International Nuclear Information System (INIS)

    Cheng Shouyu; Peng Minjun; Liu Xinkai; Zhao Qiang; Deng Xiangxin

    2014-01-01

    Nuclear power plant (NPP) is a multi-input and multi-output, no-linear and time-varying complex system. The conventional PID controller is usually used in NPP control system which is based on analog instrument. The system parameters are easy to overshoot and the response time is longer in the control mode of the conventional PID. In order to improve this condition, a new coordinated control strategy which is based on expert system and the original controllers in the digital instrument and control technology was presented. In order to verify and validate it, the proposed coordinated control technology was tested by the full-scope real-time simulation system. The results prove that using digital instrument and control technology to achieve coordinated controller is feasible, the coordinated controller can effectively improve the dynamic operating characteristics of the system, and the coordinated controller is superior to the conventional PID controller in control performance. (authors)

  18. Impact of Advanced Alarm Systems and Information Displays on Human Reliability in the Digital Control Room of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, Jong Hyun; Dang, Vinh N

    2011-01-01

    This paper discusses the potential impacts of two advanced features of digital control rooms, alarm systems and information display systems, on the Human Reliability Analysis (HRA) in nuclear power plants. Although the features of digital control rooms have already been implemented in new or upgraded nuclear power plants, HRAs have so far not taken much credit for these features. In this circumstance, this paper aims at examining the potential effects of these features on human performance and discussing how these effects can be addressed with existing HRA methods. A conclusion derivable from past experimental studies is that those features are supportive in the severe conditions such as complex scenarios and knowledge-based works. However, in the less complex scenarios and rule-based work, they may have no difference with or sometimes negative impacts on operator performance. The discussion about the impact on the HRA is provided on the basis on the THERP method

  19. Regulatory requirements for replacement of analog systems with digital upgrades

    International Nuclear Information System (INIS)

    Loeser, P.J.

    1993-01-01

    This paper reviews briefly the regulatory guidelines which must be met in order to replace analog systems in nuclear power plants with digital systems. There is a move to do such replacements for a number of reasons: analog systems are aging, and showing considerable drift; few vendors manufacture analog systems today; support and parts are hard to get; digital systems provide flexibility. There is a safety concern however about undesirable and unpredictable effects to digital safety equipment due to plant transients, accidents, post-accident condition, and EMI/RF environmental interferences. License holders must comply with the requirements of 10 C.F.R. 50.59, which deals with safety concerns with respect to any changes to operating plants which may have an impact on the safety of the plant. NRC staff is taking the position that all digital upgrades will require an evaluation under this regulation

  20. Uso de controlador PID como tecnologia eficiente em sistema de aquecimento de creche suína

    Directory of Open Access Journals (Sweden)

    Juliana de S. G. Barros

    2015-05-01

    Full Text Available O uso racional de energia elétrica em creches suínas pode ser viabilizado sem afetar o desempenho produtivo dos animais visando à sustentabilidade do setor razão por que o objetivo deste trabalho foi avaliar a eficiência de duas tecnologias de controle de temperatura em sistema de aquecimento resistivo em creche suína, no uso de energia elétrica e no ganho de peso dos leitões. Os sistemas avaliados foram: resistências elétricas suspensas com controle PID (proporcional, integral e derivativo e resistências elétricas suspensas com termostato. O experimento foi realizado durante o período de inverno, entre maio e setembro de 2013. Os critérios de comparação foram: consumo de energia elétrica (kWh, consumo específico (kWh kg-1, custo específico (R$ kg-1, indicador de eficiência elétrica no aquecimento, ganho de peso (kg e ganho de peso diário (kg d-1. O sistema de aquecimento com controlador PID, apesar de apresentar maior consumo médio, foi mais eficiente quanto ao uso de energia elétrica para produzir 1 kg de peso vivo (2,88 kWh kg-1, quanto ao custo específico (0,75 R$ kg-1 e quanto ao ganho de peso dos leitões (7,3 kg em comparação com o sistema com termostato (3,98 kWh kg-1, 1,03 R$ kg-1 e 5,2 kg, respectivamente.

  1. Digital Architecture Planning Model

    International Nuclear Information System (INIS)

    Oxstrand, Johanna Helene; Al Rashdan, Ahmad Yahya Mohammad; Bly, Aaron Douglas; Rice, Brandon Charles; Fitzgerald, Kirk; Wilson, Keith Leon

    2016-01-01

    As part of the U.S. Department of Energy's Light Water Reactor Sustainability Program, the Digital Architecture (DA) Project focuses on providing a model that nuclear utilities can refer to when planning deployment of advanced technologies. The digital architecture planning model (DAPM) is the methodology for mapping power plant operational and support activities into a DA that unifies all data sources needed by the utilities to operate their plants. The DA is defined as a collection of information technology capabilities needed to support and integrate a wide spectrum of real-time digital capabilities for performance improvements of nuclear power plants. DA can be thought of as integration of the separate instrumentation and control and information systems already in place in nuclear power plants, which are brought together for the purpose of creating new levels of automation in plant work activities. A major objective in DAPM development was to survey all key areas that needed to be reviewed in order for a utility to make knowledgeable decisions regarding needs and plans to implement a DA at the plant. The development was done in two steps. First, researchers surveyed the nuclear industry in order to learn their near-term plans for adopting new advanced capabilities and implementing a network (i.e., wireless and wire) infrastructure throughout the plant, including the power block. Secondly, a literature review covering regulatory documents, industry standards, and technical research reports and articles was conducted. The objective of the review was to identify key areas to be covered by the DAPM, which included the following: 1. The need for a DA and its benefits to the plant 2. Resources required to implement the DA 3. Challenges that need to be addressed and resolved to implement the DA 4. Roles and responsibilities of the DA implementation plan. The DAPM was developed based on results from the survey and the literature review. Model development

  2. Digital Architecture Planning Model

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna Helene [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Al Rashdan, Ahmad Yahya Mohammad [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Bly, Aaron Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Rice, Brandon Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Fitzgerald, Kirk [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Wilson, Keith Leon [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS)

    2016-03-01

    As part of the U.S. Department of Energy’s Light Water Reactor Sustainability Program, the Digital Architecture (DA) Project focuses on providing a model that nuclear utilities can refer to when planning deployment of advanced technologies. The digital architecture planning model (DAPM) is the methodology for mapping power plant operational and support activities into a DA that unifies all data sources needed by the utilities to operate their plants. The DA is defined as a collection of information technology capabilities needed to support and integrate a wide spectrum of real-time digital capabilities for performance improvements of nuclear power plants. DA can be thought of as integration of the separate instrumentation and control and information systems already in place in nuclear power plants, which are brought together for the purpose of creating new levels of automation in plant work activities. A major objective in DAPM development was to survey all key areas that needed to be reviewed in order for a utility to make knowledgeable decisions regarding needs and plans to implement a DA at the plant. The development was done in two steps. First, researchers surveyed the nuclear industry in order to learn their near-term plans for adopting new advanced capabilities and implementing a network (i.e., wireless and wire) infrastructure throughout the plant, including the power block. Secondly, a literature review covering regulatory documents, industry standards, and technical research reports and articles was conducted. The objective of the review was to identify key areas to be covered by the DAPM, which included the following: 1. The need for a DA and its benefits to the plant 2. Resources required to implement the DA 3. Challenges that need to be addressed and resolved to implement the DA 4. Roles and responsibilities of the DA implementation plan. The DAPM was developed based on results from the survey and the literature review. Model development, including

  3. Total cost of performing analog-to-digital upgrades

    International Nuclear Information System (INIS)

    Albrigo, T.

    1993-01-01

    The financial well-being of nuclear power plants in the United States is dependent on reducing costs. Rapid advances in industrial technology have created a conundrum for utility executives and their engineering staffs. Digital technology is being touted as beneficial in many ways; however, a number of significant issues have been raised regarding the adequacy and financial viability of digital systems in nuclear power plants. Actual or perceived problems with digital system design, development, and installation have caused significant financial losses for nuclear utilities. This paper provides a list of problems that must be considered in performing an analog-to-digital conversion or for doing a large digital upgrade. It is desirable that the full financial risks associated with these types of upgrades are considered. Specific problems encountered at Palo Verde nuclear generating station are reviewed to emphasize some of the problem areas

  4. Digital control in Finnish power industry applications and some research and development activities

    International Nuclear Information System (INIS)

    Haapanen, P.; Winter, M.

    1986-01-01

    First applications of digital control systems in Finnish power plants stem from a few years time. There are at present in operation two conventional peat fuelled district heating power plants and two others are under construction. In existing nuclear power plants digital control systems are not used. Feasibility studies of a new fifth nuclear power plant have been carried out and also preliminary design exercises on its control systems has been done. It seems that the use of a digital control system in this plant is an alternative worthy of consideration. The existing digital control applications and future plans for their use in the Finnish power industry are described. The rest of the paper is devoted to the reliability questions. Software reliability is a new problem area emanating from the use of programmable digital systems. A description of a cooperative project on these questions between VTT and OECD Halden Project is given. VTT has also developed an interactive computer program, RELVEC, for plant and control system reliability analysis. The structure and use of this system is described

  5. Refurbishing the reactor protection systems of VVER-440/230 and VVER-1000/320 nuclear power plants with exclusively digital IandC systems

    International Nuclear Information System (INIS)

    Martin, M.

    1997-01-01

    The refurbishment of reactor protection systems of nuclear power plants is based on two sets of requirements: engineering aspects such as performance, qualification and licensing, as well as interfaces to other systems; and cost-benefit relationships, ease of service and maintenance as well as installation during scheduled outages. A number of WWER-440 and WWER-1000 nuclear plants have announced their intention to refurbish their protection systems. Since 1994, these plants have been placing orders with Siemens for new protection systems, including the neutron flux monitoring system utilizing the advanced system TELEPERM XS. This exclusively digital IandC system provides an excellent foundation for the remaining plant service life

  6. PROVIDING PLANT DATA ANALYTICS THROUGH A SEAMLESS DIGITAL ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    Bly, Aaron; Oxstrand, Johanna

    2017-06-01

    As technology continues to evolve and become more integrated into a worker’s daily routine in the Nuclear Power industry the need for easy access to data becomes a priority. Not only does the need for data increase but the amount of data collected increases. In most cases the data is collected and stored in various software applications, many of which are legacy systems, which do not offer any other option to access the data except through the application’s user interface. Furthermore the data gets grouped in “silos” according to work function and not necessarily by subject. Hence, in order to access all the information needed for a particular task or analysis one may have to access multiple applications to gather all the data needed. The industry and the research community have identified the need for a digital architecture and more importantly the need for a Seamless Digital Environment. An SDE provides a means to access multiple applications, gather the data points needed, conduct the analysis requested, and present the result to the user with minimal or no effort by the user. In addition, the nuclear utilities have identified the need for research focused on data analytics. The effort should develop and evaluate use cases for data mining and analytics for employing information from plant sensors and database for use in developing improved business analytics. Idaho National Laboratory is leading such effort, which is conducted in close collaboration with vendors, nuclear utilities, Institute of Nuclear Power Operations, and Electric Power Research Institute. The goal of the study is to research potential approaches to building an analytics solution for equipment reliability, on a small scale, focusing on either a single piece of equipment or a single system. The analytics solution will likely consist of a data integration layer, predictive and machine learning layer and the user interface layer that will display the output of the analysis in a straight

  7. Digital Full-Scope Simulation of a Conventional Nuclear Power Plant Control Room, Phase 2: Installation of a Reconfigurable Simulator to Support Nuclear Plant Sustainability

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring; Vivek Agarwal; Kirk Fitzgerald; Jacques Hugo; Bruce Hallbert

    2013-03-01

    The U.S. Department of Energy’s Light Water Reactor Sustainability program has developed a control room simulator in support of control room modernization at nuclear power plants in the U.S. This report highlights the recent completion of this reconfigurable, full-scale, full-scope control room simulator buildout at the Idaho National Laboratory. The simulator is fully reconfigurable, meaning it supports multiple plant models developed by different simulator vendors. The simulator is full-scale, using glasstop virtual panels to display the analog control boards found at current plants. The present installation features 15 glasstop panels, uniquely achieving a complete control room representation. The simulator is also full-scope, meaning it uses the same plant models used for training simulators at actual plants. Unlike in the plant training simulators, the deployment on glasstop panels allows a high degree of customization of the panels, allowing the simulator to be used for research on the design of new digital control systems for control room modernization. This report includes separate sections discussing the glasstop panels, their layout to mimic control rooms at actual plants, technical details on creating a multi-plant and multi-vendor reconfigurable simulator, and current efforts to support control room modernization at U.S. utilities. The glasstop simulator provides an ideal testbed for prototyping and validating new control room concepts. Equally importantly, it is helping create a standardized and vetted human factors engineering process that can be used across the nuclear industry to ensure control room upgrades maintain and even improve current reliability and safety.

  8. Digital Systems Security in the nuclear scope

    International Nuclear Information System (INIS)

    Amado, I.

    2011-01-01

    Overall nuclear power plants and in particular the Spanish, work well, but to modernize and improve the operation of existing Spanish plants, perhaps the natural evolution is to use digital technologies.

  9. Software reliability evaluation of digital plant protection system development process using V and V

    International Nuclear Information System (INIS)

    Lee, Na Young; Hwang, Il Soon; Seong, Seung Hwan; Oh, Seung Rok

    2001-01-01

    In the nuclear power industry, digital technology has been introduced recently for the Instrumentation and Control (I and C) of reactor systems. For its application to the safety critical system such as Reactor Protection System(RPS), a reliability assessment is indispensable. Unlike traditional reliability models, software reliability is hard to evaluate, and should be evaluated throughout development lifecycle. In the development process of Digital Plant Protection System(DPPS), the concept of verification and validation (V and V) was introduced to assure the quality of the product. Also, test should be performed to assure the reliability. Verification procedure with model checking is relatively well defined, however, test is labor intensive and not well organized. In this paper, we developed the methodological process of combining the verification with validation test case generation. For this, we used PVS for the table specification and for the theorem proving. As a result, we could not only save time to design test case but also get more effective and complete verification related test case set. Add to this, we could extract some meaningful factors useful for the reliability evaluation both from the V and V and verification combined tests

  10. AN ANALYSIS OF TECHNICAL SECURITY CONTROL REQUIREMENTS FOR DIGITAL I&C SYSTEMS IN NUCLEAR POWER PLANTS

    Directory of Open Access Journals (Sweden)

    JAE-GU SONG

    2013-10-01

    Full Text Available Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system.

  11. Guideline of Cyber Security Policy for Digital I and C Systems in Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Zeen; Kim, Jang Seong; Kim, Kwang Jo [Information and Communications University, Daejeon (Korea, Republic of); Kang, Young Doo; Kim, Dai Il; Jeong, Choong Heui [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2007-10-15

    Recently computers and communication systems have been developed very fast and applied to various areas in many applications. This development has raised new vulnerabilities that may endanger the critical systems for nuclear safety and physical protection at the facilities. In order to protect the critical infrastructures from these new cyber attacks, we clearly need deep considerations on the risks and threats through the cyberspace. Based on these needs, many organizations which related to nuclear power plants suggested various cyber security protection methods based on regulation or technical safeguard. Even if security countermeasures against various cyber attacks are important, it is required to establish the best practices of cyber security policy by the vendor and licensee. Based on the policy they can evaluate their activities against various cyber attacks throughout the whole life cycle. In this paper, we discuss how to establish the cyber security policy for digital instrumentation and control (I and C) systems in nuclear power plants.

  12. Guideline of Cyber Security Policy for Digital I and C Systems in Nuclear Power Plant

    International Nuclear Information System (INIS)

    Kim, Zeen; Kim, Jang Seong; Kim, Kwang Jo; Kang, Young Doo; Kim, Dai Il; Jeong, Choong Heui

    2007-01-01

    Recently computers and communication systems have been developed very fast and applied to various areas in many applications. This development has raised new vulnerabilities that may endanger the critical systems for nuclear safety and physical protection at the facilities. In order to protect the critical infrastructures from these new cyber attacks, we clearly need deep considerations on the risks and threats through the cyberspace. Based on these needs, many organizations which related to nuclear power plants suggested various cyber security protection methods based on regulation or technical safeguard. Even if security countermeasures against various cyber attacks are important, it is required to establish the best practices of cyber security policy by the vendor and licensee. Based on the policy they can evaluate their activities against various cyber attacks throughout the whole life cycle. In this paper, we discuss how to establish the cyber security policy for digital instrumentation and control (I and C) systems in nuclear power plants

  13. Instrumentation and control system upgrade plan for operating PWR plants in Japan

    International Nuclear Information System (INIS)

    Ishii, Hirofumi

    1993-01-01

    Digital technology has been applied to all non-safety grade instrumentation and control (I ampersand C) systems in the latest Japanese PWR plants, and has achieved more reliable and operable systems, easier maintenance and cable reductions. In the next stage APWR plants, the digital technology will be also applied to all the I ampersand C systems including safety grade systems. Parallel to the above efforts, many backfitting programs in which the digital technology is applied to operating plants are under way to improve reliability and operability. The backfitting programs for operating plants are proceeded in two phases, synthesizing various utility's needs to improve plant availability and operability, improvement of digital technology, and complexity of the practicable replacement procedures. Phase 1 is a partial application of digital technology, while Phase 2 is a complete application of digital technology. Phase 1 has been implemented in a number of operation plants, while Phase 2 studies are in the design stage, but have not been implemented at this point. This paper presents examples of the partial application of digital technology to operating plants, and the contents of basic design for the complete application of digital technology

  14. A study on the optimal replacement periods of digital control computer's components of Wolsung nuclear power plant unit 1

    International Nuclear Information System (INIS)

    Mok, Jin Il; Seong, Poong Hyun

    1993-01-01

    Due to the failure of the instrument and control devices of nuclear power plants caused by aging, nuclear power plants occasionally trip. Even a trip of a single nuclear power plant (NPP) causes an extravagant economical loss and deteriorates public acceptance of nuclear power plants. Therefore, the replacement of the instrument and control devices with proper consideration of the aging effect is necessary in order to prevent the inadvertent trip. In this paper we investigated the optimal replacement periods of the control computer's components of Wolsung nuclear power plant Unit 1. We first derived mathematical models of optimal replacement periods to the digital control computer's components of Wolsung NPP Unit 1 and calculated the optimal replacement periods analytically. We compared the periods with the replacement periods currently used at Wolsung NPP Unit 1. The periods used at Wolsung is not based on mathematical analysis, but on empirical knowledge. As a consequence, the optimal replacement periods analytically obtained and those used in the field show a little difference. (Author)

  15. Digital data monitoring display and logging

    International Nuclear Information System (INIS)

    Ficaro, E.P.; Wehe, D.K.

    1987-01-01

    A digital data acquisition system for monitoring plant variables has been designed and implemented at the University of Michigan's Ford Nuclear Reactor (FNR), a 2 Megawatt, open-pool, research reactor. The digital data provided by this system is useful for: closed loop control, real time experimental calculations, advanced simulation-as-knowledge techniques, improved operator training, and expert system applications. The purpose of this paper is to discuss the transition to the digital data world and the anticipated applications and benefits

  16. Digital photography provides a fast, reliable, and noninvasive method to estimate anthocyanin pigment concentration in reproductive and vegetative plant tissues.

    Science.gov (United States)

    Del Valle, José C; Gallardo-López, Antonio; Buide, Mª Luisa; Whittall, Justen B; Narbona, Eduardo

    2018-03-01

    Anthocyanin pigments have become a model trait for evolutionary ecology as they often provide adaptive benefits for plants. Anthocyanins have been traditionally quantified biochemically or more recently using spectral reflectance. However, both methods require destructive sampling and can be labor intensive and challenging with small samples. Recent advances in digital photography and image processing make it the method of choice for measuring color in the wild. Here, we use digital images as a quick, noninvasive method to estimate relative anthocyanin concentrations in species exhibiting color variation. Using a consumer-level digital camera and a free image processing toolbox, we extracted RGB values from digital images to generate color indices. We tested petals, stems, pedicels, and calyces of six species, which contain different types of anthocyanin pigments and exhibit different pigmentation patterns. Color indices were assessed by their correlation to biochemically determined anthocyanin concentrations. For comparison, we also calculated color indices from spectral reflectance and tested the correlation with anthocyanin concentration. Indices perform differently depending on the nature of the color variation. For both digital images and spectral reflectance, the most accurate estimates of anthocyanin concentration emerge from anthocyanin content-chroma ratio, anthocyanin content-chroma basic, and strength of green indices. Color indices derived from both digital images and spectral reflectance strongly correlate with biochemically determined anthocyanin concentration; however, the estimates from digital images performed better than spectral reflectance in terms of r 2 and normalized root-mean-square error. This was particularly noticeable in a species with striped petals, but in the case of striped calyces, both methods showed a comparable relationship with anthocyanin concentration. Using digital images brings new opportunities to accurately quantify the

  17. A review of digital radiography technology for valve inspection

    International Nuclear Information System (INIS)

    Stoev, K.; Guerout, F.M.; Horn, D.

    2008-01-01

    There are thousands of valves in a nuclear power plant (NPP) used for control, safety and checks in various plant systems, so there is a well-identified need for fast and reliable inspection and diagnostics of valves. Digital radiography can provide considerable improvements to the inspection and testing procedures for valves in comparison to classical film radiography. These improvements can lead to significant financial advantages by providing real-time inspection results, significantly reduced inspection and decision-making time, and reduced operational cost. Digital image processing, including digital image enhancement, digital archiving, and digital communication of the images and the results, is also a considerable advantage over classical film radiography technology. Another advantage of digital radiography technology is the improved safety and the reduced environmental impact due to reduced exposure/test times, use of smaller exclusion zones, elimination of chemical processing, and absence of disposable materials. This paper reviews the existing technology and evaluates the potential of digital radiography for inspection and diagnostics of valves. Station needs and requirements are assessed, and the safety, environmental and economical constraints of digital radiography techniques estimated. The advantages and disadvantages of different digital radiography equipment are compared, and their limitations and characteristics studied. (author)

  18. A full life cycle nuclear knowledge management framework based on digital system

    International Nuclear Information System (INIS)

    Wang, Minglu; Zheng, Mingguang; Tian, Lin; Qiu, Zhongming; Li, Xiaoyan

    2017-01-01

    Highlights: • A full life cycle nuclear power plant knowledge management framework is introduced. • This framework benefits the safe design, construction, operation and maintenance. • This framework enhances safety, economy and reliability of nuclear power plant. - Abstract: The nuclear power plant is highly knowledge-intensive facility. With the rapid advent and development of modern information and communication technology, knowledge management in nuclear industry has been provided with new approaches and possibilities. This paper introduces a full cycle nuclear power plant knowledge management framework based on digital system and tries to find solutions to knowledge creation, sharing, transfer, application and further innovation in nuclear industry. This framework utilizes information and digital technology to build top-tier object driven work environment, automatic design and analysis integration platform, digital dynamic performance Verification & Validation (V&V) platform, collaborative manufacture procedure, digital construction platform, online monitoring and configuration management which benefit knowledge management in NPP full life cycle. The suggested framework will strengthen the design basis of the nuclear power plants (NPPs) and will ensure the safety of the NPP design throughout the whole lifetime of the plant.

  19. Design concepts for the reactor protection and control process instrumentation digital upgrade project at the Donald C. Cook Nuclear Plant units 1 and 2

    International Nuclear Information System (INIS)

    Carruth, R.C.; Sotos, W.G.

    1996-01-01

    As the nation's nuclear power plants age, the need to consider upgrading of their electronic protection and control systems becomes more urgent. Hardware obsolescence and mechanical wear out resulting from frequent calibration and surveillance play a major role in defining their useful life. At Cook Nuclear Plant, a decision was made to replace a major portion of the plant's protection and control systems with newer technology. This paper describes the engineering processes involved in this successful upgrade and explains the basis for many decisions made while performing the digital upgrade

  20. Abnormal condition and events analysis for instrumentation and control systems. Volume 1: Methodology for nuclear power plant digital upgrades. Final report

    International Nuclear Information System (INIS)

    McKemy, S.; Marcelli, M.; Boehmer, N.; Crandall, D.

    1996-01-01

    The ACES project was initiated to identify a cost-effective methodology for addressing abnormal conditions and events (ACES) in digital upgrades to nuclear power plant systems, as introduced by IEEE Standard 7-4.3.2-1993. Several methodologies and techniques currently in use in the defense, aerospace, and other communities for the assurance of digital safety systems were surveyed, and although several were shown to possess desirable qualities, non sufficiently met the needs of the nuclear power industry. This report describes a tailorable methodology for performing ACES analysis that is based on the more desirable aspects of the reviewed methodologies and techniques. The methodology is applicable to both safety- and non-safety-grade systems, addresses hardware, software, and system-level concerns, and can be applied in either a lifecycle or post-design timeframe. Employing this methodology for safety systems should facilitate the digital upgrade licensing process

  1. Licensing of simple digital devices

    International Nuclear Information System (INIS)

    Jackson, T. W.

    2008-01-01

    The inability to guarantee error-free software gave rise to the potential for common-cause failure of digital safety systems in nuclear power plants. To address this vulnerability, the U. S. Nuclear Regulatory Commission (NRC) required a quality software development process and a defense-in-depth and diversity analysis for digital safety systems. As a result of recent interim [NRC] staff guidance in the digital instrumentation and control (I and C) area, licensing of simple digital devices decreases some regulatory burden with respect to demonstrating a quality software development process and defense-in-depth and diversity analysis. This paper defines simple digital devices and addresses the interim staff guidance that applies to such devices. The paper also highlights the technical aspects that affect the licensing of such devices and incorporates licensing experience in the U.S. to date. (authors)

  2. An analysis of Technical Security Control Requirements For Digital I and C Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Song, Jaegu; Lee, Jungwoon; Park, Geeyong; Kwon, Keechoon; Lee, Dongyoung; Lee, Cheolkwon

    2013-01-01

    Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system

  3. An analysis of Technical Security Control Requirements For Digital I and C Systems in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jaegu; Lee, Jungwoon; Park, Geeyong; Kwon, Keechoon; Lee, Dongyoung; Lee, Cheolkwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system.

  4. Mapping soil deformation around plant roots using in vivo 4D X-ray Computed Tomography and Digital Volume Correlation.

    Science.gov (United States)

    Keyes, S D; Gillard, F; Soper, N; Mavrogordato, M N; Sinclair, I; Roose, T

    2016-06-14

    The mechanical impedance of soils inhibits the growth of plant roots, often being the most significant physical limitation to root system development. Non-invasive imaging techniques have recently been used to investigate the development of root system architecture over time, but the relationship with soil deformation is usually neglected. Correlative mapping approaches parameterised using 2D and 3D image data have recently gained prominence for quantifying physical deformation in composite materials including fibre-reinforced polymers and trabecular bone. Digital Image Correlation (DIC) and Digital Volume Correlation (DVC) are computational techniques which use the inherent material texture of surfaces and volumes, captured using imaging techniques, to map full-field deformation components in samples during physical loading. Here we develop an experimental assay and methodology for four-dimensional, in vivo X-ray Computed Tomography (XCT) and apply a Digital Volume Correlation (DVC) approach to the data to quantify deformation. The method is validated for a field-derived soil under conditions of uniaxial compression, and a calibration study is used to quantify thresholds of displacement and strain measurement. The validated and calibrated approach is then demonstrated for an in vivo test case in which an extending maize root in field-derived soil was imaged hourly using XCT over a growth period of 19h. This allowed full-field soil deformation data and 3D root tip dynamics to be quantified in parallel for the first time. This fusion of methods paves the way for comparative studies of contrasting soils and plant genotypes, improving our understanding of the fundamental mechanical processes which influence root system development. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Benefits of Digital Equipment Generic Qualification Activities

    International Nuclear Information System (INIS)

    Thomas, James E.; Steiman, Samuel C.

    2002-01-01

    As a result of nuclear power plant instrumentation and control obsolescence issues, there have been numerous activities during recent years relating to the qualification of digital equipment. Some of these activities have been 'generic' in nature in that the qualification was not limited to plant specific applications, but was intended to cover a broad base of potential applications of the digital equipment. These generic qualifications have been funded by equipment manufacturers and by utility groups and organizations. The generic activities sponsored by the Electric Power Research Institute (EPRI) have been pilot projects for an overall generic qualification approach. The primary benefit resulting from the generic qualification work to date is that a number of digital platforms and digital devices are now available for use in various nuclear safety-related applications. Many of the tests and evaluations necessary to support plant specific applications have been completed. The amount of data and documentation that each utility must develop on a case by case basis has been significantly reduced. There are also a number of additional benefits resulting from these industry efforts. The challenges and difficulties in qualifying digital equipment for safety-related applications are now more clearly understood. EPRI has published a lessons learned document (EPRI Report 1001452, Generic Qualification of Commercial Grade Digital Devices: Lessons Learned from Initial Pilots, which covers several different qualification areas, including device selection, project planning, vendor surveys and design reviews, and electromagnetic compatibility (EMC) qualification. Application of the experience and lessons learned from the EPRI pilot activities should help reduce the effort and cost required for future qualification work. Most generic qualification activities for commercial equipment have been conducted using the approach of EPRI TR-106439, Guideline on Evaluation and Acceptance

  6. Speed control and generation of electric power of a gas turbine by means of fuzzy-logic; Control de velocidad y de generacion de potencia electrica de una turbina de gas mediante logica difusa

    Energy Technology Data Exchange (ETDEWEB)

    Bahamaca Fernandez, Luis Jonathan

    2000-08-01

    The development of a fuzzy-logic control algorithm is presented. It was developed for the speed and load control of a gas turbine. The speed/load controller of the gas turbine which were conventional Pi's were completely replaced by the fuzzy-logic controllers. The fuzzy controllers correspond to MISO systems that has as input the error an its rate of change and as an output the control signal for the fuel valve. The fuzzy controller provides an algorithm that can turn a strategy of linguistic control (based on knowledge of experts) into a strategy of automatic control. The fuzzy controllers were validated by the development of functional test in a simulation of a nonlinear mathematical gas-turbine model. The controllers were programmed in C language in PC. Simulation test for the speed regulation and load tracking were used for the controller validation. The fuzzy controller had a good performance because the minimized the signal error produced by the set of programmed system perturbations (due to control actions). Besides, they had a better reference tracking then PI controllers. Consequently, the proposed fuzzy controllers have a better performance than the conventional control system. [Spanish] En este trabajo de tesis se presenta el diseno, programacion y evaluacion de un algoritmo de control basado en logica difusa para el control de velocidad y generacion de potencia electrica de una turbina de gas. En el esquema de control velocidad/carga de la turbina de gas, se sustituyeron completamente los dos controladores convencionales del tipo PI por controladores difusos, teniendo asi un control digital directo. Los controladores difusos corresponden a sistemas MISO que utilizan como variables de entrada el error y la derivada del error, y como variable de salida la senal de control a la valvula de combustible. De esta forma, un controlador difuso provee un algoritmo que puede convertir una estrategia de control linguistico (basado en conocimiento de expertos

  7. Supporting plant operation through computer-based procedures

    International Nuclear Information System (INIS)

    Martinez, Victor; Medrano, Javier; Mendez, Julio

    2014-01-01

    Digital Systems are becoming more important in controlling and monitoring nuclear power plant operations. The capabilities of these systems provide additional functions as well as support operators in making decisions and avoiding errors. Regarding Operation Support Systems, an important way of taking advantage of these features is using computer-based procedures (CBPs) tools that enhance the plant operation. Integrating digital systems in analogue controls at nuclear power plants in operation becomes an extra challenge, in contrast to the integration of Digital Control Systems in new nuclear power plants. Considering the potential advantages of using this technology, Tecnatom has designed and developed a CBP platform taking currently operating nuclear power plants as its design basis. The result is a powerful tool which combines the advantages of CBPs and the conventional analogue control systems minimizing negative effects during plant operation and integrating operation aid-systems to support operators. (authors)

  8. Digital I and C: Safety, Security and Availability

    International Nuclear Information System (INIS)

    Liebhart, E.

    2012-01-01

    When planning to use digital I and C equipment in nuclear facilities (such as nuclear power plants or research reactors) the main concern is how to manage and control the aspect of 'software as part of digital I and C equipment'. Advantages, possible implications and risks of using digital signal processing channels, especially regarding the two key aspects of operational safety and cyber security are addressed, including examples of today's electronics such as Mirion's digital signal processing system Model proTK (or TK 250). (author)

  9. Comparison of Failure Analysis and Operating Experiences of Digital Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Chan; Shin, Tae Young [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2014-08-15

    This study focuses on digital control systems that have the same functions but different designs. Some differences and common points between these two digital control systems are analyzed in terms of vulnerabilities in plant operation. In addition, this study confirms why unexpected outcomes can occur through a comparison of the system failure experiences with the analytic results of FMEA and FTA. This evaluation demonstrates that the digital system may have vulnerable components whose single failures can cause plant transients even if the system has a redundant structure according to its system design.

  10. Hardware replacements and software tools for digital control computers

    International Nuclear Information System (INIS)

    Walker, R.A.P.; Wang, B-C.; Fung, J.

    1996-01-01

    Technological obsolescence is an on-going challenge for all computer use. By design, and to some extent good fortune, AECL has had a good track record with respect to the march of obsolescence in CANDU digital control computer technology. Recognizing obsolescence as a fact of life, AECL has undertaken a program of supporting the digital control technology of existing CANDU plants. Other AECL groups are developing complete replacement systems for the digital control computers, and more advanced systems for the digital control computers of the future CANDU reactors. This paper presents the results of the efforts of AECL's DCC service support group to replace obsolete digital control computer and related components and to provide friendlier software technology related to the maintenance and use of digital control computers in CANDU. These efforts are expected to extend the current lifespan of existing digital control computers through their mandated life. This group applied two simple rules; the product, whether new or replacement should have a generic basis, and the products should be applicable to both existing CANDU plants and to 'repeat' plant designs built using current design guidelines. While some exceptions do apply, the rules have been met. The generic requirement dictates that the product should not be dependent on any brand technology, and should back-fit to and interface with any such technology which remains in the control design. The application requirement dictates that the product should have universal use and be user friendly to the greatest extent possible. Furthermore, both requirements were designed to anticipate user involvement, modifications and alternate user defined applications. The replacements for hardware components such as paper tape reader/punch, moving arm disk, contact scanner and Ramtek are discussed. The development of these hardware replacements coincide with the development of a gateway system for selected CANDU digital control

  11. Application of extended statistical combination of uncertainties methodology for digital nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    In, Wang Ki; Uh, Keun Sun; Chul, Kim Heui [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-02-01

    A technically more direct statistical combinations of uncertainties methodology, extended SCU (XSCU), was applied to statistically combine the uncertainties associated with the DNBR alarm setpoint and the DNBR trip setpoint of digital nuclear power plants. The modified SCU (MSCU) methodology is currently used as the USNRC approved design methodology to perform the same function. In this report, the MSCU and XSCU methodologies were compared in terms of the total uncertainties and the net margins to the DNBR alarm and trip setpoints. The MSCU methodology resulted in the small total penalties due to a significantly negative bias which are quite large. However the XSCU methodology gave the virtually unbiased total uncertainties. The net margins to the DNBR alarm and trip setpoints by the MSCU methodology agree with those by the XSCU methodology within statistical variations. (Author) 12 refs., 17 figs., 5 tabs.

  12. Harmonization of the licensing process for digital instrumentation and control systems in nuclear power plants. Report prepared within the framework of the Technical Working Group on Nuclear Power Plant Control and Instrumentation

    International Nuclear Information System (INIS)

    2002-12-01

    This report was prepared in response to the recommendation of the Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI). This recommendation was based on the recognition of the present diversity in national practices in licensing digital Instrumentation and control (I and C). The goal of this report is to promote harmonization of I and C licensing requirements in the Member States. It applies to I and C modernization, retrofits, upgrades, replacement, new installation, and other aspects of digital I and C in both existing and new nuclear power plants. It should be pointed out that a single publication, like this report, can only take the first step towards initiating a process leading to licensing requirements, which are more harmonized. It is therefore hoped that that this report will get a broad readership among those who can influence requirements that are set on digital I and C. This report provides general and high level recommendations to assist senior officials at utilities, vendor organizations, regulatory bodies, and their support organizations who are involved in the licensing of digital I and C. It is also intended to be read by persons participating in technical committees which are writing standards. The authors of this report believe that harmonization can be achieved through a consideration of the technical and scientific basis of high integrity digital I and C systems. It is also believed that many benefits can be reached in resolving various issues of a technical and engineering nature, which presently are creating controversies in the licensing of digital I and C in NPP safety applications. This publication is based on a consideration of the licensing process of I and C in a top down fashion to discuss generic principles to be applied when assessing digital I and C in NPP safety applications. This report gives an overview of the confidence building process in which evidence is created that digital I and C fulfils

  13. A Method and Support Tool for the Analysis of Human Error Hazards in Digital Devices

    International Nuclear Information System (INIS)

    Lee, Yong Hee; Kim, Seon Soo; Lee, Yong Hee

    2012-01-01

    In recent years, many nuclear power plants have adopted modern digital I and C technologies since they are expected to significantly improve their performance and safety. Modern digital technologies were expected to significantly improve both the economical efficiency and safety of nuclear power plants. However, the introduction of an advanced main control room (MCR) is accompanied with lots of changes in forms and features and differences through virtue of new digital devices. Many user-friendly displays and new features in digital devices are not enough to prevent human errors in nuclear power plants (NPPs). It may be an urgent to matter find the human errors potentials due to digital devices, and their detailed mechanisms. We can then consider them during the design of digital devices and their interfaces. The characteristics of digital technologies and devices may give many opportunities to the interface management, and can be integrated into a compact single workstation in an advanced MCR, such that workers can operate the plant with minimum burden under any operating condition. However, these devices may introduce new types of human errors, and thus we need a means to evaluate and prevent such errors, especially within digital devices for NPPs. This research suggests a new method named HEA-BIS (Human Error Analysis based on Interaction Segment) to confirm and detect human errors associated with digital devices. This method can be facilitated by support tools when used to ensure the safety when applying digital devices in NPPs

  14. Digital maintenance field technology for the maintenance of nuclear power plant

    International Nuclear Information System (INIS)

    Sato, Tomomasa; Asama, Hajime; Kita, Nobuyuki; Numano, Masayoshi

    2002-01-01

    This paper proposes a concept of 'Digital Maintenance Field Technology', which enables human beings and working robots making fully use of the necessary information for maintenance activity not only in any location of the maintenance field (seamless in location) but also in any moment from the past to the future (seamless in time) and in any format in presenting to human (seamless in semantics). The paper points out the following three essential components of the technology: 1) 'Digital Field Construction Technology', 2) 'Digital Field Archival Technology' and 3) 'Digital Field Presentation Technology'. The necessary capabilities are extracted and our approaches and state of the art of realizing these capabilities are introduced in addition to present the state of the art of home application example. The future extension is also illustrated. (author)

  15. Experience of digital control systems in Scandinavian BWRs

    International Nuclear Information System (INIS)

    Rydahl, I.

    1989-01-01

    Since 1984 digital control systems have been in operation in various Scandinavian BWRs. Examples of such digital control systems are: dual microprocessor based system for complete control of radwaste plant, three channel recirculation control system, and three channel feedwater control system. This paper describes Swedish development from one channel through three channel analog control systems to digital systems. The author describes experience of digital control systems during design, testing, commissioning and operation. The main benefits of digital compared with analog technology are discussed. Especially the outstanding facility of using a built-in process simulator for commissioning and tuning. The use of digital technology in nuclear safety system and future plans are dealt with

  16. Environmental testing of an experimental digital safety channel

    International Nuclear Information System (INIS)

    Korsah, K.; Tanaka, T.J.; Wilson, T.L. Jr.; Wood, R.T.

    1996-09-01

    This document presents the results of environmental stress tests performed on an experimental digital safety channel (EDSC) assembled at the Oak Ridge National Laboratory (ORNL) as part of the NRC-sponsored Qualification of Advanced Instrumentation and Controls (W) System program. The objective of this study is to investigate failure modes and vulnerabilities of microprocessor-based technologies when subjected to environmental stressors. The study contributes to the technical basis for environmental qualification of safety-related digital I ampersand C systems. The EDSC employs technologies and digital subsystems representative of those proposed for use in advanced light-water reactors (ALWRs) or for retrofits in existing plants. Subsystems include computers, electrical and optical serial communication links, fiber-optic network links, analog-to-digital and digital-to-analog converters, and multiplexers. The EDSC was subjected to selected stressors that are a potential risk to digital equipment in a mild environment. The selected stressors were electromagnetic and radio-frequency interference (EMYRFI), temperature, humidity, and smoke exposure. The stressors were applied over ranges that were considerably higher than what the channel is likely to experience in a normal nuclear power plant environment. Ranges of stress were selected at a sufficiently high level to induce errors so that failure modes that are characteristic of the technologies employed could be identified

  17. Leech Therapy For The Treatment Of Venous Congestion In Flaps, Digital Re-Plants And Revascularizations - A Two-Year Review From A Regional Centre.

    Science.gov (United States)

    Butt, Ahsan Masood; Ismail, Amir; Lawson-Smith, Matthew; Shahid, Muhammad; Webb, Jill; Chester, Darren L

    2016-01-01

    Leeches are a well-recognized treatment for congested tissue. This study reviewed the efficacy of leech therapy for salvage of venous congested flaps and congested replanted or revascularized hand digits over a 2-year period. All patients treated with leeches between 1 Oct 2010 and 30 Sep 2012 (two years) at Queen Elizabeth Hospital, Birmingham, UK were included in the study. Details regarding mode of injury requiring reconstruction, surgical procedure, leech therapy duration, subsequent surgery requirement and tissue salvage rates were recorded. Twenty tissues in 18 patients required leeches for tissue congestion over 2 years: 13 men and 5 women. The mean patient age was 41 years (range 17-79). The defect requiring reconstruction was trauma in 16 cases, following tumour resection in two, and two miscellaneous causes. Thirteen cases had flap reconstruction and seven digits in six patients had hand digit replantations or revascularisation. Thirteen of 20 cases (65%) had successful tissue salvage following leech therapy for congestion (77% in 10 out of 13 flaps, and 43% in 3 of 7 digits). The rate of tissue salvage in pedicled flaps was good 6/6 (100%) and so was in digital revascularizations 2/3 (67%), but poor in digital re-plants 1/4 (25%) and free flaps 0/2 (0%). Leeches are a helpful tool for congested tissue salvage and in this study, showed a greater survival benefit for pedicled flaps than for free flaps or digital replantations.

  18. Control Predictivo en Cascada de un Vehículo Autónomo

    Directory of Open Access Journals (Sweden)

    Guilherme V. Raffo

    2009-01-01

    Full Text Available Resumen: Este trabajo presenta el diseño de un controlador predictivo basado en modelo para las dinámicas lateral y longitudinal de un vehículo autónomo. El controlador propuesto se implementa mediante una estructura en cascada con el control de la cinemática del vehículo para obtener las prestaciones deseadas a altas velocidades para el problema de seguimiento de trayectoria. Se utiliza un controlador predictivo descentralizado basado en el modelo dinámico linealizado del vehículo. Resultados experimentales con el controlador cinemático y resultados de simulación utilizando el controlador cascada propuesto son mostrados para corroborar el análisis teórico presentado. Palabras clave: vehículo autónomo, control predictivo, seguimiento de trayectoria, control de deslizamiento lateral

  19. Immunizing digital systems against electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced

  20. Immunizing digital systems against electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced

  1. Digital I and C system upgrade integration technique

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H. W. [Inst. of Nuclear Energy Research (INER), No. 1000, Wenhua Road, Chiaan Village, Longtan Township, Taoyuan County, 32546, Taiwan (China); Shih, C. [Inst. of Nuclear Engineering and Science, National Tsing Hua Univ., 101, Sec. 2, Kuang Fu Rd, Hsinchu, Taiwan (China); Wang, J. R. [Inst. of Nuclear Energy Research (INER), No. 1000, Wenhua Road, Chiaan Village, Longtan Township, Taoyuan County, 32546, Taiwan (China); Huang, K. C. [Inst. of Nuclear Engineering and Science, National Tsing Hua Univ., 101, Sec. 2, Kuang Fu Rd, Hsinchu, Taiwan (China)

    2012-07-01

    This work developed an integration technique for digital I and C system upgrade, the utility can replace the I and C systems step by step systematically by this method. Inst. of Nuclear Energy Research (INER) developed a digital Instrumentation and Control (I and C) replacement integration technique on the basis of requirement of the three existing nuclear power plants (NPPs), which are Chin-Shan (CS) NPP, Kuo-Sheng (KS) NPP, and Maanshan (MS) NPP, in Taiwan, and also developed the related Critical Digital Review (CDR) Procedure. The digital I and C replacement integration technique includes: (I) Establishment of Nuclear Power Plant Digital Replacement Integration Guideline, (2) Preliminary Investigation on I and C System Digitalization, (3) Evaluation on I and C System Digitalization, and (4) Establishment of I and C System Digitalization Architectures. These works can be a reference for performing I and C system digital replacement integration of the three existing NPPs of Taiwan Power Company (TPC). A CDR is the review for a critical system digital I and C replacement. The major reference of this procedure is EPRI TR- 1011710 (2005) 'Handbook for Evaluating Critical Digital Equipment and Systems' which was published by the Electric Power Research Inst. (EPRI). With this document, INER developed a TPC-specific CDR procedure. Currently, CDR becomes one of the policies for digital I and C replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The CDR review items include the comparison of the design change, Software Verification and Validation (SVandV), Failure Mode and Effects Analysis (FMEA), Evaluation of Diversity and Defense-in-depth (D3), Evaluation of Watchdog Timer, Evaluation of Electromagnetic Compatibility (EMC), Evaluation of Grounding for System/Component, Seismic Evaluation, Witness and Inspection, Lessons Learnt from the Digital I and C Failure

  2. Digital I and C system upgrade integration technique

    International Nuclear Information System (INIS)

    Huang, H. W.; Shih, C.; Wang, J. R.; Huang, K. C.

    2012-01-01

    This work developed an integration technique for digital I and C system upgrade, the utility can replace the I and C systems step by step systematically by this method. Inst. of Nuclear Energy Research (INER) developed a digital Instrumentation and Control (I and C) replacement integration technique on the basis of requirement of the three existing nuclear power plants (NPPs), which are Chin-Shan (CS) NPP, Kuo-Sheng (KS) NPP, and Maanshan (MS) NPP, in Taiwan, and also developed the related Critical Digital Review (CDR) Procedure. The digital I and C replacement integration technique includes: (I) Establishment of Nuclear Power Plant Digital Replacement Integration Guideline, (2) Preliminary Investigation on I and C System Digitalization, (3) Evaluation on I and C System Digitalization, and (4) Establishment of I and C System Digitalization Architectures. These works can be a reference for performing I and C system digital replacement integration of the three existing NPPs of Taiwan Power Company (TPC). A CDR is the review for a critical system digital I and C replacement. The major reference of this procedure is EPRI TR- 1011710 (2005) 'Handbook for Evaluating Critical Digital Equipment and Systems' which was published by the Electric Power Research Inst. (EPRI). With this document, INER developed a TPC-specific CDR procedure. Currently, CDR becomes one of the policies for digital I and C replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The CDR review items include the comparison of the design change, Software Verification and Validation (SVandV), Failure Mode and Effects Analysis (FMEA), Evaluation of Diversity and Defense-in-depth (D3), Evaluation of Watchdog Timer, Evaluation of Electromagnetic Compatibility (EMC), Evaluation of Grounding for System/Component, Seismic Evaluation, Witness and Inspection, Lessons Learnt from the Digital I and C Failure Events. A

  3. Accurate measurement of transgene copy number in crop plants using droplet digital PCR.

    Science.gov (United States)

    Collier, Ray; Dasgupta, Kasturi; Xing, Yan-Ping; Hernandez, Bryan Tarape; Shao, Min; Rohozinski, Dominica; Kovak, Emma; Lin, Jeanie; de Oliveira, Maria Luiza P; Stover, Ed; McCue, Kent F; Harmon, Frank G; Blechl, Ann; Thomson, James G; Thilmony, Roger

    2017-06-01

    Genetic transformation is a powerful means for the improvement of crop plants, but requires labor- and resource-intensive methods. An efficient method for identifying single-copy transgene insertion events from a population of independent transgenic lines is desirable. Currently, transgene copy number is estimated by either Southern blot hybridization analyses or quantitative polymerase chain reaction (qPCR) experiments. Southern hybridization is a convincing and reliable method, but it also is expensive, time-consuming and often requires a large amount of genomic DNA and radioactively labeled probes. Alternatively, qPCR requires less DNA and is potentially simpler to perform, but its results can lack the accuracy and precision needed to confidently distinguish between one- and two-copy events in transgenic plants with large genomes. To address this need, we developed a droplet digital PCR-based method for transgene copy number measurement in an array of crops: rice, citrus, potato, maize, tomato and wheat. The method utilizes specific primers to amplify target transgenes, and endogenous reference genes in a single duplexed reaction containing thousands of droplets. Endpoint amplicon production in the droplets is detected and quantified using sequence-specific fluorescently labeled probes. The results demonstrate that this approach can generate confident copy number measurements in independent transgenic lines in these crop species. This method and the compendium of probes and primers will be a useful resource for the plant research community, enabling the simple and accurate determination of transgene copy number in these six important crop species. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  4. The modular design method for digital control systems in Japanese BWRs

    International Nuclear Information System (INIS)

    Kondoh, Y.; Motomura, A.

    1998-01-01

    Digital technology is being applied to control systems in nuclear power plants. Especially in Japanese BWRs, control systems are being digitized both in constructing plant and in retrofit of operating plants. Digital technology has many advantages compared with analog technology. However, its high performance and flexibility may result in too complicated software structure, which will cause long design time and long testing time and increase cost. In introduction of digital technology, it is most important to restrict unnecessary flexibility of software. The function of control systems can be divided in standard part and variable part. Standard function may be common to every plant while variable function should be designed for each plant. Even in current design, standard design is preserved to be reused in next application. However, this design approach is not always effective because standard function may be changed by customer and nothing is considered for variable part even if it is large. To keep reliability and reduce cost by software reuse, Toshiba adopts modular design of control software, where standard part is designed as a set of standard functional modules and variable function is designed as a complex of standard functional modules and plant unique modules. Toshiba firstly applied modular design method to fuel handling machine control system. In this application the design work has been reduced to 30 percent by reusing of functional module which was first developed in former applications. This remarkable reduction of design work has enhanced reliability with less cost. In addition, software, has been produced and tested according to the functional module. These qualified software modules will be applied to next system and will realize highest reliability and least cost. Toshiba is now planning the application of this modular design method for every digital control system. (author)

  5. Digital System Reliability Test for the Evaluation of safety Critical Software of Digital Reactor Protection System

    Directory of Open Access Journals (Sweden)

    Hyun-Kook Shin

    2006-08-01

    Full Text Available A new Digital Reactor Protection System (DRPS based on VME bus Single Board Computer has been developed by KOPEC to prevent software Common Mode Failure(CMF inside digital system. The new DRPS has been proved to be an effective digital safety system to prevent CMF by Defense-in-Depth and Diversity (DID&D analysis. However, for practical use in Nuclear Power Plants, the performance test and the reliability test are essential for the digital system qualification. In this study, a single channel of DRPS prototype has been manufactured for the evaluation of DRPS capabilities. The integrated functional tests are performed and the system reliability is analyzed and tested. The results of reliability test show that the application software of DRPS has a very high reliability compared with the analog reactor protection systems.

  6. Research on transfer rule of the monitoring of operator in digital main control room of nuclear power plant

    International Nuclear Information System (INIS)

    Zhang Li; Li Linfeng; Li Pengcheng; Lu Changshen; Huang Weigang; Dai Zhonghua; Huang Yuanzheng; Chen Qingqing

    2013-01-01

    In the digital main control room of nuclear power plants, monitoring the operating status of the system of reactor is not only one of the most important tasks of the operators, but also the basis and premise of controlling the system of reactor running correctly. After analyzing, inducing, summarizing the data obtained, we found the operators' monitor behavior could be classified as procedure transfer, abnormal transfer, and exchange transfer. The times of exchange transfer is 29% of the total transfer times, abnormal transfer is 14%, regulation transfer is 36%, and others are 21%. (authors)

  7. MATLAB simulation for an experimental setup of digital feedback control

    International Nuclear Information System (INIS)

    Zheng Lifang; Liu Songqiang

    2005-01-01

    This paper describes the digital feedback simulation using MATLAB for an experimental accelerator control setup. By analyzing the plant characteristic in time-domain and frequency-domain, a guideline for design of digital filter and PID controller is derived. (authors)

  8. Nuclear plant operations, maintenance, and configuration management using three-dimensional computer graphics and databases

    International Nuclear Information System (INIS)

    Tutos, N.C.; Reinschmidt, K.F.

    1987-01-01

    Stone and Webster Engineering Corporation has developed the Plant Digital Model concept as a new approach to Configuration Mnagement of nuclear power plants. The Plant Digital Model development is a step-by-step process, based on existing manual procedures and computer applications, and is fully controllable by the plant managers and engineers. The Plant Digital Model is based on IBM computer graphics and relational database management systems, and therefore can be easily integrated with existing plant databases and corporate management-information systems

  9. Neuralfussy multivariable control applied to the control of velocity, power, and exhaust gas temperature of a turbo gas unit; Control neurodifuso multivariable aplicado al control de velocidad, potencia y temperatura de gases de escape de una unidad turbogas

    Energy Technology Data Exchange (ETDEWEB)

    Segura Ozuna, Victor Octavio

    2004-11-15

    construccion mas cortos, a bajos niveles de emision de contaminantes y costos de operacion competitivos. El sistema de control de las unidades turbogas esta basado en algoritmos de control convencionales del tipo PI [2]. Este esquema de control es destinado para tareas de regulacion y rechazo a perturbaciones, y no para seguimiento de puntos de referencia. Los controladores actuan todos sobre una sola valvula de control, lo cual representa una fuerte interaccion entre los mismos, por ejemplo un ajuste en los parametros del algoritmo del PI digital de temperatura, puede mejorar su desempeno pero tambien puede afectar el desempeno del control de velocidad o el de potencia. La turbina de gas presenta un comportamiento no lineal y variante en el tiempo, principalmente en la etapa de arranque donde se presentan varios disturbios importantes. Actualmente, los controladores utilizados en los esquemas de control de las turbinas son lineales, los cuales son sintonizados para un punto de operacion especifico y son conservados asi por tiempo indefinido. En esta tesis se presenta la formulacion de un controlador prealimentado multivariable, disenado con la combinacion de las tecnologias de logica difusa y redes neuronales con el proposito de mejorar el control de velocidad, potencia y temperatura de la UTG. Este control propuesto es usado en conjuncion con el esquema de control convencional de la UTG existente, para integrar una estrategia de control hibrida prealimentada. El control prealimentado esta compuesto por un sistema de inferencia difuso de multiples entradas y una sola salida disenado con datos de entrada y salida de la planta. El controlador retroalimentado esta compuesto por controladores tipo PI convencionales en este tipo de unidades. Con esta estrategia, el controlador prealimentado provee una mayor contribucion en la senal de control disminuyendo el esfuerzo de control de los controladores PI convencionales y la fuerte interaccion que existe entre ellos. Los controladores

  10. Issues regarding Risk Effect Analysis of Digitalized Safety Systems and Main Risk Contributors

    International Nuclear Information System (INIS)

    Kang, Hyun Gook; Jang, Seung-Cheol

    2008-01-01

    Risk factors of safety-critical digital systems affect overall plant risk. In order to assess this risk effect, a risk model of a digitalized safety system is required. This article aims to provide an overview of the issues when developing a risk model and demonstrate their effect on plant risk quantitatively. Research activities in Korea for addressing these various issues, such as the software failure probability and the fault coverage of self monitoring mechanism are also described. The main risk contributors related to the digitalized safety system were determined in a quantitative manner. Reactor protection system and engineered safety feature component control system designed as part of the Korean Nuclear I and C System project are used as example systems. Fault-tree models were developed to assess the failure probability of a system function which is designed to generate an automated signal for actuating both of the reactor trip and the complicated accident-mitigation actions. The developed fault trees were combined with a plant risk model to evaluate the effect of a digitalized system's failure on the plant risk. (authors)

  11. Licensing of digital Instrumentation and Control in Radioisotope Production Facility

    International Nuclear Information System (INIS)

    Abdel-Aziz, L.Kh.; Lashin, R.; Mostafa, W.

    2012-01-01

    In spite of the rapid development of digital I and C systems in all major industries, it has for several reasons been slower in nuclear power plants. The most important reason is that only a few new plants have been ordered worldwide during the last ten years. A second reason is connected to the efforts needed in providing adequate evidence that the digital I and C system can be used in safety and safety related applications. This issue is connected to the effort needed in obtaining adequate assurance that the digital I and C will fulfill its intended function and contain no unintended function in all possible operational states during its entire life cycle. This paper presents an acceptance criteria for licensing a digital instrumentation and control system in a Radioisotope Production Facility(1), which is under commissioning. The acceptance criteria ensure that the I and C systems are designed to reach the highest degree of reliability with respect to the function they perform, operators will have clear and accessible availability to data on every plant parameter, and also ensure that the safety objectives have been covered

  12. A dynamic failure evaluation of a simplified digital control system of a nuclear power plant pressurizer

    International Nuclear Information System (INIS)

    Pinto, J.M.O.; Melo, P.F. Frutuoso e; Saldanha, P.L.C.

    2010-01-01

    Given the increasing use of digital systems in nuclear power plants, a specific approach to reliability and risk analysis has been required. The digital system reflects many interactions between hardware, software, process variables, and human actions. At the same time, the software, does not have a reliability approach as well-defined as the one existing for the other physical components of the system. Then, its reliability analysis is still under development due to difficulties arising from the complexity, flexibility and interactions present in such systems.The traditional approach of using fault trees is static and does not approach the dynamic interactions in such systems, such as delays in capture and processing information, memory, logic loops, system states, etc. It is necessary to find a reliability methodology that takes into account these issues without violating the existing requirements concerning safety analysis, such as: ability to distinguish between common-cause failures, availability of relevant information to users, like minimal cut sets, and failure probabilities as long as the possibility of incorporating the results into existing probabilistic safety assessments (PSA).One approach is to trace all the possible errors of the digital system through dynamic methodologies. The DFM (Dynamic Flow-graph Methodology) is one of the methodologies that better meets the requirements for modeling dynamic systems. It discretizes the most relevant variables of the analyzed system in states that reflect their behavior, sets the logic that connects them through decision tables and finally performs a system analysis, aiming, for example, the root causes (prime implicants) of a given top event of failure. Three aspects have been addressed, the modeling of the system itself, the incorporation of results to probabilistic safety analyses and identification of software failures.To illustrate the DFM, a simplified digital control system of a typical PWR pressurizer

  13. Reliability analysis of digital based I and C system

    Energy Technology Data Exchange (ETDEWEB)

    Kang, I. S.; Cho, B. S.; Choi, M. J. [KOPEC, Yongin (Korea, Republic of)

    1999-10-01

    Rapidly, digital technology is being widely applied in replacing analog component installed in existing plant and designing new nuclear power plant for control and monitoring system in Korea as well as in foreign countries. Even though many merits of digital technology, it is being faced with a new problem of reliability assurance. The studies for solving this problem are being performed vigorously in foreign countries. The reliability of KNGR Engineered Safety Features Component Control System (ESF-CCS), digital based I and C system, was analyzed to verify fulfillment of the ALWR EPRI-URD requirement for reliability analysis and eliminate hazards in design applied new technology. The qualitative analysis using FMEA and quantitative analysis using reliability block diagram were performed. The results of analyses are shown in this paper.

  14. Design of the Fully Digitalized SOE System in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Jong Yong, Keum; Geun Ok, Park; Heui Youn, Park; Gui Sook, Jang

    2006-01-01

    With the spread of the digital technologies, the Instrumentation and Control (I and C) systems including the Sequence of Events (SOE) system in the nuclear power plants gradually follow these general trends. This paper discusses the methods for calculating SOE events' occurrence time in each of the non-safety systems and the safety systems. This paper presents the structure of a fully digitalized SOE system in the I and C systems and takes the important design elements of the SOE systems into consideration, including the time resolution, time protocol, and the properties of the data communication networks in the non-safety systems and the safety systems. The feature of the SOE system is that the processing of the SOE events' occurrence time is distributed in their individual systems except for the safety systems processed in a gateway. The commercial data communication networks adopting TCP/IP are used in the non-safety systems and the safety systems use the deterministic data communication networks in order to produce their output within restricted time. Under the two different data communications networks, the methods for establishing the SOE events' occurrence time which are classified into a safety grade and a non-safety grade are applied here. The Network Time Protocol (NTP) is used to synchronize the time keeping among the time servers and the clients in the non-safety systems. When the SOE events occur, the clients record the time information from their own local clocks. The safety systems are designed to precisely calculate the SOE events' occurrence time. The equation defined as a function of a transmission time, a transmission waiting time and an arrival time to a gateway is presented here. This paper analyzed the time errors of the SOE events in non-safety systems by using NTP through an experimental environment. In the case of the safety systems, the principle for the calculation of the SOE events' occurrence time is explained by an example. (authors)

  15. Probabilistic safety assessment for digital instrumentation and control systems in nuclear power plants - a review

    International Nuclear Information System (INIS)

    Lu, L.; Jiang, J.

    2003-01-01

    Deregulation in electricity market has created a great deal of challenges for nuclear power industries [1]. To stay competitive, Nuclear Power Plants (NPPs) will have to find ways to reduce their operational costs and to improve the plant safety. Instrumentation and Control (I and C) systems play an important role in this regard. Thus, new methodologies need to be developed to manage the operation of I and C systems more economically without jeopardizing the overall plant safety. Probabilistic Safety Assessment (PSA) technique is one of the promising methods to deal with such an issue, because PSA analyzes various system operational issues from a probabilistic sense, rather than a worst-case approach. However, there are several limitations when PSA is applied to I and C systems directly. A possible solution to this problem can be found by incorporating PSA with several other approaches. To better understand the issues involved, an attempt has been made in this paper to carry out a literature survey on this and related subject, particularly the effort will be made on: 1) the development of digital I and C systems in NPP, 2) PSA and its potential benefits and limitations, and 3) applications of PSA in various aspects of I and C systems including the resource allocation, the determination of surveillance testing strategies and the design of I and C systems. Finally, some solutions to overcome the aforementioned obstacles when applying PSA in I and C systems are also examined critically. (author)

  16. Upgrading the Reactor Power Control Concept with a Modern Digital Control System

    International Nuclear Information System (INIS)

    Laengle, M.; Schildheuer, R.

    2011-01-01

    Within the framework of a retrofit project, a reactor power instrumentation and control system (REALL) - consisting of a limiting system and the respective reactor control systems - was retrofitted and modernized in a 1450-MW-nuclear-power-plant in Baden-Wuerttemberg. The REALL process control functions were implemented within a modern and completely digitized control system that has been designed for use in safety I and C applications. Along with the installation of the digital control system, the associated hardware was adapted to today's state of the art. At the same time, the given potential for improvement, as revealed during the plant's operation so far, was taken into account in the programming. In order to provide for transparent and quality-assured project management, the implementation was based on a stage plan consisting of several steps, along with specific milestones. Final commissioning of the modern digital control system took place during the 2008 plant overhaul. Despite the complex commissioning procedure, it was possible to avoid a major prolongation of the plant's downtime and to keep within a rough 4-week timeframe that had originally been defined for the plant overhaul to adequate structuring of the project, goal-oriented implementation of preparatory infrastructural measures and adequate scheduling of the coordinated activities of the installation and commissioning teams entrusted with the commissioning of the digital control system during the overhaul activities. (author)

  17. NRC perspectives on the digital system review process

    International Nuclear Information System (INIS)

    Mauck, J.L.

    1998-01-01

    Since about 1988, the USNRC has been involved in the review of digital retrofits to instrumentation and control (I and C) systems in nuclear power plants. Initially, this involvement was limited but with the advent of the 1990s, NRC involvement has become greater because of increased interest in and application of digital systems as existing analog systems become obsolete. Criteria for the design of such systems to ensure safety has been promulgated over the years and the USNRC has been actively involved both nationally and internationally with this effort. With the publication of the Zion Eagle 21 Safety Evaluation Report in 1992, Generic Letter 95-02 in April 1995 which endorses EPRI guidance document TR-102348 on digital upgrades and the latest revision to Regulatory Guide 1.152 which endorses IEEE 7.4.3.2-1993; a basic digital system review process was established. The NRC supplemented this review process with recently issued inspection procedures for use by NRC inspectors when conducting onsite reviews of digital modifications. In addition, the NRC undertook a major effort to codify the above guidance and the experience gained from digital system reviews of both operating plant modifications and advanced reactor designs, over these years into a revision to Standard Review Plan, (SRP), NUREG-0800, Chapter 7, Instrumentation and Control. This SRP revision was published in June, 1997, and included new SRP sections, branch technical positions and six new regulatory guides endorsing IEEE standards on software quality. The NRC staff believes that a stable digital system review process is now in place. (author)

  18. Review report: safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States Nuclear Regulatory Commission's dispositions

    International Nuclear Information System (INIS)

    Watanabe, Norio; Suzudo, Tomoaki

    1998-09-01

    Recently, digital instrumentation and control (I and C) systems have been applied to nuclear power plants (NPPs) in various countries. Introduction of digital I and C systems, however, raises special issues on design, implementation, safety and licensing. Since FY 1997, the Japan Atomic Energy Research Institute (JAERI) has been carrying out a project, Study on Reliability of Digital I and C Systems, which includes extensive reviews of design approaches, technical standards, regulatory processes, especially, in the United States. This report summarizes the results from the study of National Research Council (NRC) and the U.S. Nuclear Regulatory Commission's (USNRC's) responses to the recommendations made by the NRC's study. That study identified six technical key issues (system aspects of digital I and C technology, software quality assurance, common-mode software failure potential, safety and reliability assessment methods, human factors and man-machine interface, dedication of commercial off-the-shelf hardware and software) and two strategic key issues (case-by-case licensing process, adequacy of technical infrastructure) that arise from the introduction of digital I and C technology and then, made recommendations to the USNRC for coping with digital I and C applications. The USNRC responded to each recommendation and showed their own dispositions in which the USNRC agreed with most of the recommendations. In Japan, it is expected that introduction of digital I and C technology is inevitable in NPPs because the vendors are gradually discontinuing support and stocking of analog components. To cope with such situations, there is a need to develop and update the standards and guidelines applicable to digital I and C technology. The key issues and the USNRC's dispositions provided in this report is believed to be useful for developing and updating them. (J.P.N.)

  19. Digital Technology for Construction Period Reduction of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    You, Y. M. [PHILOSOPHIA, Inc., Seoul (Korea, Republic of); Suh, K. Y. [Seoul National Univ., Seoul (Korea, Republic of)

    2009-10-15

    PHILOSOPHIA, Inc. and Seoul National University have jointly developed a first-of-a-kind engineering (FOAKE) solution. The solution lends itself to the four-plus-dimensional (4{sup +}D) Technology{sup TM} resorting to three -dimensional (3D) computer-aided design (CAD) digital mockup (DMU). The aim is to minimize the working hours via process optimization by real-time exchange of design and process information in the ubiquitous system. The 4{sup +}D Technology{sup TM} in the 3D virtual reality (VR) space and time plus cost coordinates, is developed to reduce the construction time as well as cost of nuclear power plants (NPPs) by optimizing the manufacturing procedure and construction process. The 4{sup +}D Technology{sup TM} anchored to the 3D CAD DMU allows the interference of the NPP components to be checked upon early in the design stage, and the process sequences to be optimized. Moreover, its ergonomic and robotic technologies enable simulation of all the aspects of the workers, robots and machines involved in the construction process. One of the greatest advantages of the 4{sup +}D Technology{sup TM} lies in that any change of the overall process procedures can virtually be tested. On the other hand, it shall financially be unbearable to alter the procedures consisting of plenty of structures and components, complicated detailed processes and long work hours in the physical space.

  20. Digital Technology for Construction Period Reduction of Nuclear Power Plants

    International Nuclear Information System (INIS)

    You, Y. M.; Suh, K. Y.

    2009-01-01

    PHILOSOPHIA, Inc. and Seoul National University have jointly developed a first-of-a-kind engineering (FOAKE) solution. The solution lends itself to the four-plus-dimensional (4 + D) Technology TM resorting to three -dimensional (3D) computer-aided design (CAD) digital mockup (DMU). The aim is to minimize the working hours via process optimization by real-time exchange of design and process information in the ubiquitous system. The 4 + D Technology TM in the 3D virtual reality (VR) space and time plus cost coordinates, is developed to reduce the construction time as well as cost of nuclear power plants (NPPs) by optimizing the manufacturing procedure and construction process. The 4 + D Technology TM anchored to the 3D CAD DMU allows the interference of the NPP components to be checked upon early in the design stage, and the process sequences to be optimized. Moreover, its ergonomic and robotic technologies enable simulation of all the aspects of the workers, robots and machines involved in the construction process. One of the greatest advantages of the 4 + D Technology TM lies in that any change of the overall process procedures can virtually be tested. On the other hand, it shall financially be unbearable to alter the procedures consisting of plenty of structures and components, complicated detailed processes and long work hours in the physical space

  1. Review of Software Reliability Assessment Methodologies for Digital I and C Software of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jae Hyun; Lee, Seung Jun; Jung, Won Dea [KAERI, Daejeon (Korea, Republic of)

    2014-08-15

    Digital instrumentation and control (I and C) systems are increasingly being applied to current nuclear power plants (NPPs) due to its advantages; zero drift, advanced data calculation capacity, and design flexibility. Accordingly, safety issues of software that is main part of the digital I and C system have been raised. As with hardware components, the software failure in NPPs could lead to a large disaster, therefore failure rate test and reliability assessment of software should be properly performed, and after that adopted in NPPs. However, the reliability assessment of the software is quite different with that of hardware, owing to the nature difference between software and hardware. The one of the most different thing is that the software failures arising from design faults as 'error crystal', whereas the hardware failures are caused by deficiencies in design, production, and maintenance. For this reason, software reliability assessment has been focused on the optimal release time considering the economy. However, the safety goal and public acceptance of the NPPs is so distinctive with other industries that the software in NPPs is dependent on reliability quantitative value rather than economy. The safety goal of NPPs compared to other industries is exceptionally high, so conventional methodologies on software reliability assessment already used in other industries could not adjust to safety goal of NPPs. Thus, the new reliability assessment methodology of the software of digital I and C on NPPs need to be developed. In this paper, existing software reliability assessment methodologies are reviewed to obtain the pros and cons of them, and then to assess the usefulness of each method to software of NPPs.

  2. Review of Software Reliability Assessment Methodologies for Digital I and C Software of Nuclear Power Plants

    International Nuclear Information System (INIS)

    Cho, Jae Hyun; Lee, Seung Jun; Jung, Won Dea

    2014-01-01

    Digital instrumentation and control (I and C) systems are increasingly being applied to current nuclear power plants (NPPs) due to its advantages; zero drift, advanced data calculation capacity, and design flexibility. Accordingly, safety issues of software that is main part of the digital I and C system have been raised. As with hardware components, the software failure in NPPs could lead to a large disaster, therefore failure rate test and reliability assessment of software should be properly performed, and after that adopted in NPPs. However, the reliability assessment of the software is quite different with that of hardware, owing to the nature difference between software and hardware. The one of the most different thing is that the software failures arising from design faults as 'error crystal', whereas the hardware failures are caused by deficiencies in design, production, and maintenance. For this reason, software reliability assessment has been focused on the optimal release time considering the economy. However, the safety goal and public acceptance of the NPPs is so distinctive with other industries that the software in NPPs is dependent on reliability quantitative value rather than economy. The safety goal of NPPs compared to other industries is exceptionally high, so conventional methodologies on software reliability assessment already used in other industries could not adjust to safety goal of NPPs. Thus, the new reliability assessment methodology of the software of digital I and C on NPPs need to be developed. In this paper, existing software reliability assessment methodologies are reviewed to obtain the pros and cons of them, and then to assess the usefulness of each method to software of NPPs

  3. Low cost driver device for microclimate maintenance in the pre-milking of dairy cattle Dispositivo controlador de baixo custo para a manutenção do microclima na pré-ordenha de bovinos leiteiros

    Directory of Open Access Journals (Sweden)

    Irenilson M. da Silva

    2013-02-01

    Full Text Available Due to the importance of the environment on animal production and thus environmental control, the study aims to build a system for monitoring and control the meteorological variables, temperature and relative humidity, low cost, which can be associated with an evaporative cooling system (ECS. The system development included all the stages of assembly, test and laboratory calibration, and later the validation of the equipment carried in the field. The validation step showed results which allowed concluding that the system can be safely used in the monitoring of these variables. The controller was efficient in management of the microclimate in the waiting corral and allowed the maintenance of the air temperature within the comfort range for dairy cattle in pre-milking with averaged 25.09 ºC during the afternoon. The equipment showed the lower cost (R$ 325.76 when compared to other middle market (R$ 450.00.Devido à importância do ambiente na produção animal e, portanto, do controle ambiental adequado, objetivou-se com este trabalho a construção de um sistema de monitoramento e controle das variáveis meteorológicas, temperatura e umidade relativa do ar, de baixo custo, associado a um sistema de resfriamento adiabático evaporativo (SRAE. O desenvolvimento do sistema controlador compreendeu as etapas de montagem, teste e aferição em laboratório e, posteriormente, a etapa de validação do equipamento realizada a campo. A etapa de validação apresentou resultados que permitiram concluir que o sistema pode ser utilizado com segurança no monitoramento e controle dessas variáveis por meio dos atuadores. O controlador mostrou-se eficiente no manejo do microclima no curral de espera e permitiu a manutenção da temperatura do ar dentro da faixa de conforto para bovinos leiteiros na pré-ordenha, apresentando média de 25,09 ºC durante o turno da tarde. O equipamento apresentou custo inferior (R$ 325,76 quando comparado à média de outros

  4. The Effect of Degraded Digital Instrumentation and Control systems on Human-system Interfaces and Operator Performance

    International Nuclear Information System (INIS)

    O'Hara, J.M.; Gunther, B.; Martinez-Guridi, G.; Xing, J.; Barnes, V.

    2010-01-01

    Integrated digital instrumentation and control (I and C) systems in new and advanced nuclear power plants (NPPs) will support operators in monitoring and controlling the plants. Even though digital systems typically are expected to be reliable, their potential for degradation or failure significantly could affect the operators performance and, consequently, jeopardize plant safety. This U.S. Nuclear Regulatory Commission (NRC) research investigated the effects of degraded I and C systems on human performance and on plant operations. The objective was to develop technical basis and guidance for human factors engineering (HFE) reviews addressing the operator's ability to detect and manage degraded digital I and C conditions. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we evaluated the potential effects of selected failure modes of the digital feedwater control system of a currently operating pressurized water reactor (PWR) on human-system interfaces (HSIs) and the operators performance. Our findings indicated that I and C degradations are prevalent in plants employing digital systems, and the overall effects on the plant's behavior can be significant, such as causing a reactor trip or equipment to operate unexpectedly. I and C degradations may affect the HSIs used by operators to monitor and control the plant. For example, deterioration of the sensors can complicate the operators interpretation of displays, and sometimes may mislead them by making it appear that a process disturbance has occurred. We used the findings as the technical basis upon which to develop HFE review guidance.

  5. Reliability modeling of safety-critical network communication in a digitalized nuclear power plant

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Kim, Hee Eun; Son, Kwang Seop; Shin, Sung Min; Lee, Seung Jun; Kang, Hyun Gook

    2015-01-01

    The Engineered Safety Feature-Component Control System (ESF-CCS), which uses a network communication system for the transmission of safety-critical information from group controllers (GCs) to loop controllers (LCs), was recently developed. However, the ESF-CCS has not been applied to nuclear power plants (NPPs) because the network communication failure risk in the ESF-CCS has yet to be fully quantified. Therefore, this study was performed to identify the potential hazardous states for network communication between GCs and LCs and to develop quantification schemes for various network failure causes. To estimate the risk effects of network communication failures in the ESF-CCS, a fault-tree model of an ESF-CCS signal failure in the containment spray actuation signal condition was developed for the case study. Based on a specified range of periodic inspection periods for network modules and the baseline probability of software failure, a sensitivity study was conducted to analyze the risk effect of network failure between GCs and LCs on ESF-CCS signal failure. This study is expected to provide insight into the development of a fault-tree model for network failures in digital I&C systems and the quantification of the risk effects of network failures for safety-critical information transmission in NPPs. - Highlights: • Network reliability modeling framework for digital I&C system in NPP is proposed. • Hazardous states of network protocol between GC and LC in ESF-CCS are identified. • Fault-tree model of ESF-CCS signal failure in ESF actuation condition is developed. • Risk effect of network failure on ESF-CCS signal failure is analyzed.

  6. A Practical Introduction to Skeletons for the Plant Sciences

    Directory of Open Access Journals (Sweden)

    Alexander Bucksch

    2014-08-01

    Full Text Available Before the availability of digital photography resulting from the invention of charged couple devices in 1969, the measurement of plant architecture was a manual process either on the plant itself or on traditional photographs. The introduction of cheap digital imaging devices for the consumer market enabled the wide use of digital images to capture the shape of plant networks such as roots, tree crowns, or leaf venation. Plant networks contain geometric traits that can establish links to genetic or physiological characteristics, support plant breeding efforts, drive evolutionary studies, or serve as input to plant growth simulations. Typically, traits are encoded in shape descriptors that are computed from imaging data. Skeletons are one class of shape descriptors that are used to describe the hierarchies and extent of branching and looping plant networks. While the mathematical understanding of skeletons is well developed, their application within the plant sciences remains challenging because the quality of the measurement depends partly on the interpretation of the skeleton. This article is meant to bridge the skeletonization literature in the plant sciences and related technical fields by discussing best practices for deriving diameters and approximating branching hierarchies in a plant network.

  7. MEASUREMENT OF LARGE-SCALE SOLAR POWER PLANT BY USING IMAGES ACQUIRED BY NON-METRIC DIGITAL CAMERA ON BOARD UAV

    Directory of Open Access Journals (Sweden)

    R. Matsuoka

    2012-07-01

    Full Text Available This paper reports an experiment conducted in order to investigate the feasibility of the deformation measurement of a large-scale solar power plant on reclaimed land by using images acquired by a non-metric digital camera on board a micro unmanned aerial vehicle (UAV. It is required that a root mean squares of errors (RMSE in height measurement should be less than 26 mm that is 1/3 of the critical limit of deformation of 78 mm off the plane of a solar panel. Images utilized in the experiment have been obtained by an Olympus PEN E-P2 digital camera on board a Microdrones md4-1000 quadrocopter. The planned forward and side overlap ratios of vertical image acquisition have been 60 % and 60 % respectively. The planned flying height of the UAV has been 20 m above the ground level and the ground resolution of an image is approximately 5.0 mm by 5.0 mm. 8 control points around the experiment area are utilized for orientation. Measurement results are evaluated by the space coordinates of 220 check points which are corner points of 55 solar panels selected from 1768 solar panels in the experiment area. Two teams engage in the experiment. One carries out orientation and measurement by using 171 images following the procedure of conventional aerial photogrammetry, and the other executes those by using 126 images in the manner of close range photogrammetry. The former fails to satisfy the required accuracy, while the RMSE in height measurement by the latter is 8.7 mm that satisfies the required accuracy. From the experiment results, we conclude that the deformation measurement of a large-scale solar power plant on reclaimed land by using images acquired by a nonmetric digital camera on board a micro UAV would be feasible if points utilized in orientation and measurement have a sufficient number of bundles in good geometry and self-calibration in orientation is carried out.

  8. Safety aspect of digital reactor protection system in Japan

    International Nuclear Information System (INIS)

    Ogiso, Zen-Ichi

    1998-01-01

    It was early in 1980's that the digital controllers were first applied to nuclear power plant in japan. After that, their application area had been expanding gradually, reaching to the overall integrated digital system including the safety system in Kashiwazaki-Kariwa units 6 and 7. The software for computer-based systems has been produced using the graphical language ''POL'' in Japanese nuclear power plants. It is the fundamental principle that the reliability of the software should be assured through the properly managed quality assurance. The POL-based system is fitted to this principle. In applying POL-based systems to safety system, the MITI, Ministry of International Trade and Industry, identified the licensing issues as the regulatory body, while the utilities had developed the digital technology feasible to the safety application. Through the activities, a specific industrial design guide for the software important to safety was established and the adequacy of the technology was certified through the demonstration tests of the integrated system. In the safety examination of the digital reactor protection system of K-6/7, the application of POL were approved. The POL-based systems in nuclear power plants were successful design and production process of the POL-based systems. This paper describes the activities in licensing and maintaining the computer-based systems by the utilities and manufacturers as well as the MITI. (author)

  9. Archiving plant inspection data in a virtual environment

    International Nuclear Information System (INIS)

    Kita, Nobuyuki; Kita, Yasuyo; Yang, Hai-quan

    2004-01-01

    ''Digital Maintenance Field Technology'' was proposed for reliable and robust maintenance of a nuclear power plant. It digitizes and maintains whole information of maintenance fields in computer system for a long time. Digital Field Archival Technology'' is one of three core technologies of the ''Digital Maintenance Field Technology''. The essential functions of the Digital Field Archival Technology'' is to store, maintain and visualize the inspection data during a long period. In order to enable the operators or other agents to review the plant information at any time, at any location and in any form, the information must be stored with collect indexes of time and space. The virtual space resembling the real space is suitable to store the observed information. In this paper, the concept to store the observed information into the virtual space is realized under the assumption that the geometrical structure of real plant is static and reconstructed in the virtual space. The system for storing observed information especially image data gotten by mobile inspection robots and visualizing the stored data as desired is introduced. (author)

  10. Digital electro-hydraulic control system for nuclear turbine

    International Nuclear Information System (INIS)

    Yokota, Yutaka; Tone, Youichi; Ozono, Jiro

    1985-01-01

    The unit capacity of steam turbines for nuclear power generation is very large, accordingly their unexpected stop disturbs power system, and the lowering of their capacity ratio exerts large influence on power generation cost. Therefore, very high reliability is required for turbine EHC controllers which directly control the turbines for nuclear power generation. In order to meet such requirement, Toshiba Corp. has developed high reliability type analog tripled turbine EHC controllers, and delivered them to No. 3 plant in the Fukushima No. 2 Nuclear Power Station and No. 1 plant in the Kashiwazaki Kariwa Nuclear Power Station, Tokyo Electric Power Co., Inc. At present, the trial operation is under way. The development of digital EHC controllers was begun in 1976, and through the digital EHC for a test turbine and that for a small turbine, the digital EHC controllers for the turbines for nuclear power generation were developed. In this paper, the function, constitution, features and maintenance of the digital tripled EHC controllers for the turbines for nuclear power generation, the application of new technology to them, and the confirmation of the control function by simulation are reported. (Kako, I.)

  11. Digital Architecture – Results From a Gap Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna Helene [Idaho National Lab. (INL), Idaho Falls, ID (United States); Thomas, Kenneth David [Idaho National Lab. (INL), Idaho Falls, ID (United States); Fitzgerald, Kirk [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    The digital architecture is defined as a collection of IT capabilities needed to support and integrate a wide-spectrum of real-time digital capabilities for nuclear power plant performance improvements. The digital architecture can be thought of as an integration of the separate I&C and information systems already in place in NPPs, brought together for the purpose of creating new levels of automation in NPP work activities. In some cases, it might be an extension of the current communication systems, to provide digital communications where they are currently analog only. This collection of IT capabilities must in turn be based on a set of user requirements that must be supported for the interconnected technologies to operate in an integrated manner. These requirements, simply put, are a statement of what sorts of digital work functions will be exercised in a fully-implemented seamless digital environment and how much they will be used. The goal of the digital architecture research is to develop a methodology for mapping nuclear power plant operational and support activities into the digital architecture, which includes the development of a consensus model for advanced information and control architecture. The consensus model should be developed at a level of detail that is useful to the industry. In other words, not so detailed that it specifies specific protocols and not so vague that it is only provides a high level description of technology. The next step towards the model development is to determine the current state of digital architecture at typical NPPs. To investigate the current state, the researchers conducted a gap analysis to determine to what extent the NPPs can support the future digital technology environment with their existing I&C and IT structure, and where gaps exist with respect to the full deployment of technology over time. The methodology, result, and conclusions from the gap analysis are described in this report.

  12. Qualification of safety-critical software for digital reactor safety system in nuclear power plants

    International Nuclear Information System (INIS)

    Kwon, Kee-Choon; Park, Gee-Yong; Kim, Jang-Yeol; Lee, Jang-Soo

    2013-01-01

    This paper describes the software qualification activities for the safety-critical software of the digital reactor safety system in nuclear power plants. The main activities of the software qualification processes are the preparation of software planning documentations, verification and validation (V and V) of the software requirements specifications (SRS), software design specifications (SDS) and codes, and the testing of the integrated software and integrated system. Moreover, the software safety analysis and software configuration management are involved in the software qualification processes. The V and V procedure for SRS and SDS contains a technical evaluation, licensing suitability evaluation, inspection and traceability analysis, formal verification, software safety analysis, and an evaluation of the software configuration management. The V and V processes for the code are a traceability analysis, source code inspection, test case and test procedure generation. Testing is the major V and V activity of the software integration and system integration phases. The software safety analysis employs a hazard operability method and software fault tree analysis. The software configuration management in each software life cycle is performed by the use of a nuclear software configuration management tool. Through these activities, we can achieve the functionality, performance, reliability, and safety that are the major V and V objectives of the safety-critical software in nuclear power plants. (author)

  13. Adjustable control in the steam zone of a steam power plant; Control ajustable de la zona de vapor de una unidad termoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Gallegos, Joaquin; Bourguet Diaz, Rafael Ernesto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1991-12-31

    A general description is presented of self adjustable control systems, as well as of the design and its application for steam temperature regulation of a steam power plant unit model. The algorithm employed is a controller of minimum variance that ponders the output deviation as well as the control effort. The results are compared with the ones obtained in a conventional control scheme, showing in general a better performance in the conducted experiments. [Espanol] Se presenta una descripcion general de los sistemas de control autoajustable, asi como del diseno y su aplicacion para regular las temperaturas de vapor de un modelo de unidad termoelectrica. El algoritmo utilizado es un controlador de variancia minima que pondera tanto la desviacion de salida como el esfuerzo de control. Los resultados se comparan con los obtenidos en un esquema de control convencional, mostrando en general un mejor desempeno en los experimentos realizados.

  14. Adjustable control in the steam zone of a steam power plant; Control ajustable de la zona de vapor de una unidad termoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Gallegos, Joaquin; Bourguet Diaz, Rafael Ernesto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    A general description is presented of self adjustable control systems, as well as of the design and its application for steam temperature regulation of a steam power plant unit model. The algorithm employed is a controller of minimum variance that ponders the output deviation as well as the control effort. The results are compared with the ones obtained in a conventional control scheme, showing in general a better performance in the conducted experiments. [Espanol] Se presenta una descripcion general de los sistemas de control autoajustable, asi como del diseno y su aplicacion para regular las temperaturas de vapor de un modelo de unidad termoelectrica. El algoritmo utilizado es un controlador de variancia minima que pondera tanto la desviacion de salida como el esfuerzo de control. Los resultados se comparan con los obtenidos en un esquema de control convencional, mostrando en general un mejor desempeno en los experimentos realizados.

  15. A customized digital monitoring and display system for nonpower reactors

    International Nuclear Information System (INIS)

    Ficaro, E.P.; Wehe, D.K.

    1989-01-01

    A digital data acquisition system for monitoring plant variables has been designed and implemented at the University of Michigan's Ford Nuclear Reactor (FNR), a 2-MW open-pool research reactor. The digital data provided by this system will be useful for: improved operator training, real-time experimental calculations, noise analysis, closed-loop control, and expert system applications. This paper describes the analog-to-digital (A/D) transitions and the associated applications and benefits experienced

  16. A preliminary user-friendly, digital console for the control room parameters supervision in old-generation Nuclear Plants

    Energy Technology Data Exchange (ETDEWEB)

    Memmi, F.; Falconi, L.; Cappelli, M.; Palomba, M.; Santoro, E.; Bove, R.; Sepielli, M. [UTFISST, ENEA Casaccia, via Anguillarese 301, Rome (Italy)

    2012-07-01

    Improvements in the awareness of a system status is an essential requirement to achieve safety in every kind of plant. In particular, in the case of Nuclear Power Plants (NPPs), a progress is crucial to enhance the Human Machine Interface (HMI) in order to optimize monitoring and analyzing processes of NPP operational states. Firstly, as old-fashioned plants are concerned, an upgrading of the whole console instrumentation is desirable in order to replace an analog visualization with a full-digital system. In this work, we present a novel instrument able to interface the control console of a nuclear reactor, developed by using CompactRio, a National Instruments embedded architecture and its dedicated programming language. This real-time industrial controller composed by a real-time processor and FPGA modules has been programmed to visualize the parameters coming from the reactor, and to storage and reproduce significant conditions anytime. This choice has been made on the basis of the FPGA properties: high reliability, determinism, true parallelism and re-configurability, achieved by a simple programming method, based on LabVIEW real-time environment. The system architecture exploits the FPGA capabilities of implementing custom timing and triggering, hardware-based analysis and co-processing, and highest performance control algorithms. Data stored during the supervisory phase can be reproduced by loading data from a measurement file, re-enacting worthwhile operations or conditions. The system has been thought to be used in three different modes, namely Log File Mode, Supervisory Mode and Simulation Mode. The proposed system can be considered as a first step to develop a more complete Decision Support System (DSS): indeed this work is part of a wider project that includes the elaboration of intelligent agents and meta-theory approaches. A synoptic has been created to monitor every kind of action on the plant through an intuitive sight. Furthermore, another important

  17. A preliminary user-friendly, digital console for the control room parameters supervision in old-generation Nuclear Plants

    International Nuclear Information System (INIS)

    Memmi, F.; Falconi, L.; Cappelli, M.; Palomba, M.; Santoro, E.; Bove, R.; Sepielli, M.

    2012-01-01

    Improvements in the awareness of a system status is an essential requirement to achieve safety in every kind of plant. In particular, in the case of Nuclear Power Plants (NPPs), a progress is crucial to enhance the Human Machine Interface (HMI) in order to optimize monitoring and analyzing processes of NPP operational states. Firstly, as old-fashioned plants are concerned, an upgrading of the whole console instrumentation is desirable in order to replace an analog visualization with a full-digital system. In this work, we present a novel instrument able to interface the control console of a nuclear reactor, developed by using CompactRio, a National Instruments embedded architecture and its dedicated programming language. This real-time industrial controller composed by a real-time processor and FPGA modules has been programmed to visualize the parameters coming from the reactor, and to storage and reproduce significant conditions anytime. This choice has been made on the basis of the FPGA properties: high reliability, determinism, true parallelism and re-configurability, achieved by a simple programming method, based on LabVIEW real-time environment. The system architecture exploits the FPGA capabilities of implementing custom timing and triggering, hardware-based analysis and co-processing, and highest performance control algorithms. Data stored during the supervisory phase can be reproduced by loading data from a measurement file, re-enacting worthwhile operations or conditions. The system has been thought to be used in three different modes, namely Log File Mode, Supervisory Mode and Simulation Mode. The proposed system can be considered as a first step to develop a more complete Decision Support System (DSS): indeed this work is part of a wider project that includes the elaboration of intelligent agents and meta-theory approaches. A synoptic has been created to monitor every kind of action on the plant through an intuitive sight. Furthermore, another important

  18. Review report: safety and reliability issues on digital instrumentation and control systems in nuclear power plants and United States Nuclear Regulatory Commission`s dispositions

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Norio; Suzudo, Tomoaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-09-01

    Recently, digital instrumentation and control (I and C) systems have been applied to nuclear power plants (NPPs) in various countries. Introduction of digital I and C systems, however, raises special issues on design, implementation, safety and licensing. Since FY 1997, the Japan Atomic Energy Research Institute (JAERI) has been carrying out a project, Study on Reliability of Digital I and C Systems, which includes extensive reviews of design approaches, technical standards, regulatory processes, especially, in the United States. This report summarizes the results from the study of National Research Council (NRC) and the U.S. Nuclear Regulatory Commission`s (USNRC`s) responses to the recommendations made by the NRC`s study. That study identified six technical key issues (system aspects of digital I and C technology, software quality assurance, common-mode software failure potential, safety and reliability assessment methods, human factors and man-machine interface, dedication of commercial off-the-shelf hardware and software) and two strategic key issues (case-by-case licensing process, adequacy of technical infrastructure) that arise from the introduction of digital I and C technology and then, made recommendations to the USNRC for coping with digital I and C applications. The USNRC responded to each recommendation and showed their own dispositions in which the USNRC agreed with most of the recommendations. In Japan, it is expected that introduction of digital I and C technology is inevitable in NPPs because the vendors are gradually discontinuing support and stocking of analog components. To cope with such situations, there is a need to develop and update the standards and guidelines applicable to digital I and C technology. The key issues and the USNRC`s dispositions provided in this report is believed to be useful for developing and updating them. (J.P.N.)

  19. Digitizing instrumentation and control systems in nuclear power plants. DAtF autumn meeting Leittec '96, October 8, 1996 in Koenigswinter

    International Nuclear Information System (INIS)

    Aleite, W.

    1997-01-01

    Recently, digitization for upgrading and retrofitting of instrumentation and control systems has been extended to German nuclear power plants, and initial action to commence modification started with a very suitable system, the limiters of the Neckar-1 reactor unit of GKN. This action is generally welcomed. Systems of the control room of relevance to safety -even if not belonging to priority classes - are systems for process information for example, or operator guidance, as well as diagnostic systems for inspection and maintenance. (orig./DG) [de

  20. FATORES CONTROLADORES DA EVOLUÇÃO DO RELEVO NO FLANCO NNW DO RIFT CONTINENTAL DO SUDESTE DO BRASIL: UMA ANÁLISE BASEADA NA MENSURAÇÃO DOS PROCESSOS DENUDACIONAIS DE LONGO-TERMO

    Directory of Open Access Journals (Sweden)

    Éric Andrade Rezende

    2013-03-01

    Full Text Available O presente trabalho tem como objetivo estudar os fatores controladores da evolução do relevo de um trecho do interflúvio entre a bacia interiorana do rio Grande, um dos formadores do rio Paraná, e a bacia do rio Paraíba do Sul. Este divisor hidrográfico está contido em uma das porções mais elevadas da Serra da Mantiqueira e coincide com o flanco NNW do Rift Continental do Sudeste do Brasil. Para este estudo foram selecionadas nove sub-bacias localizadas no extremo sul de Minas Gerais, entre os municípios de Itamonte e Bocaina de Minas. Essas sub-bacias tiveram suas taxas denudacionais estimadas pela mensuração da produção do isótopo cosmogênico 10Be em sedimentos fluviais. Os resultados mostram que a taxa média de denudação das sub-bacias do rio Paraíba do Sul, voltadas para o gráben (17,39 m/Ma, é superior a das sub-bacias dos rios Grande e Aiuruoca, voltadas para o interior continental (12,24 m/Ma. Entre os fatores controladores das taxas de denudação, se destaca a boa correlação existente entre as taxas e dois parâmetros morfométricos: amplitude de relevo e declividade média das sub-bacias. A influência da litologia também se mostra importante, já que a resistência dos granitos frente aos processos erosivos é um dos fatores que condiciona taxas denudacionais bastante baixas na área. Os resultados indicam que o granito Maromba é a unidade litológica mais resistente entre aquelas presentes nas sub-bacias amostradas. As baixas taxas mensuradas, referentes às últimas dezenas de milhares de anos, contrastam com o relevo rejuvenescido e com as elevadas altitudes desse setor da Mantiqueira, onde há um reconhecido papel da neotectônica na morfogênese. Deste modo, é provável que tenha havido uma atenuação da atividade tectônica no Quaternário Superior, com a consequente estabilização dos níveis de base e diminuição dos processos denudacionais.

  1. Single event upset mitigation techniques for FPGAs utilized in nuclear power plant digital instrumentation and control

    International Nuclear Information System (INIS)

    Wang Xin; Holbert, Keith E.; Clark, Lawrence T.

    2011-01-01

    Highlights: → Triple modular redundancy (TMR) implementation is the best solution for digital I and C. → Maximal probability of two simultaneous errors with TMR maximum partition is 4.44%. → Dual modular redundancy minimum logic partitioning design is an additional option. - Abstract: Field programmable gate arrays (FPGAs) are integrated circuits being increasingly used for digital instrumentation and control (I and C) in nuclear power plants (NPPs) because of low cost, re-configurability and low design turn-around time. However, to ensure reliability, proper design techniques must be employed since the memory and logic in FPGAs are susceptible to single event upsets (SEUs). Triple modular redundancy (TMR) has become a common SEU mitigation design technique because of its straightforward implementation and reliable results. Partitioned TMR approaches are introduced in this paper, and formulae derived indicate that the maximum probability of two simultaneous errors [P E ] max is inversely proportional to the number of logic partitions in a TMR design, when each redundant logic block in every logic partition has the same number of sensitive nodes. However, the maximum logic partitioning design cannot completely eliminate the possibility of two simultaneous upsets. For the example test circuit it is found that [P E ] max is reduced dramatically from 66.67% for minimum logic partitioning to 4.44% for maximum logic partitioning. Because TMR introduces significant overhead due to its full hardware redundancy, a dual modular redundancy approach is also examined for application to less demanding situations. By comparative analysis this study reaches the conclusion that the maximum logic partitioning TMR implementation is the best solution for digital I and C applications in NPPs where obtaining robustness is of the highest importance, despite its higher area overhead.

  2. On the network protocol performance evaluation for large scale communication system of nuclear plant

    International Nuclear Information System (INIS)

    Song, K. S.; Lee, T. H.; Kim, H. R.; Kim, D. H.; Ku, I. S.

    1998-01-01

    Computer technology has been dramatically advanced and it is now natural to apply digital network technology into nuclear plants. Communication architecture for nuclear plant defines the coordination of safety reactor control, balance of plant, subsystem utilities, and plant monitoring functions, and how they are connected and their user interface to guarantee plant performance and guarantee safety requirements. Therefore, to implement a digital network for control and monitoring systems of advanced nuclear plant needs systematic design and evaluation procedures because of responsive and hard real-time process characteristics of nuclear plant. In this paper, we evaluate several digital network protocols in terms of network delay, link failure effects to hard real-time requirements with full scale traffic

  3. Addressing the susceptibility of digital systems to electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a verification and validation (V ampersand V) program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate acceptance should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation susceptibility attributable to EMI will be greatly reduced

  4. Considerations of the Software Metric-based Methodology for Software Reliability Assessment in Digital I and C Systems

    International Nuclear Information System (INIS)

    Ha, J. H.; Kim, M. K.; Chung, B. S.; Oh, H. C.; Seo, M. R.

    2007-01-01

    Analog I and C systems have been replaced by digital I and C systems because the digital systems have many potential benefits to nuclear power plants in terms of operational and safety performance. For example, digital systems are essentially free of drifts, have higher data handling and storage capabilities, and provide improved performance by accuracy and computational capabilities. In addition, analog replacement parts become more difficult to obtain since they are obsolete and discontinued. There are, however, challenges to the introduction of digital technology into the nuclear power plants because digital systems are more complex than analog systems and their operation and failure modes are different. Especially, software, which can be the core of functionality in the digital systems, does not wear out physically like hardware and its failure modes are not yet defined clearly. Thus, some researches to develop the methodology for software reliability assessment are still proceeding in the safety-critical areas such as nuclear system, aerospace and medical devices. Among them, software metric-based methodology has been considered for the digital I and C systems of Korean nuclear power plants. Advantages and limitations of that methodology are identified and requirements for its application to the digital I and C systems are considered in this study

  5. Optimal design methods for a digital human-computer interface based on human reliability in a nuclear power plant

    International Nuclear Information System (INIS)

    Jiang, Jianjun; Zhang, Li; Xie, Tian; Wu, Daqing; Li, Min; Wang, Yiqun; Peng, Yuyuan; Peng, Jie; Zhang, Mengjia; Li, Peiyao; Ma, Congmin; Wu, Xing

    2017-01-01

    Highlights: • A complete optimization process is established for digital human-computer interfaces of Npps. • A quick convergence search method is proposed. • The authors propose an affinity error probability mapping function to test human reliability. - Abstract: This is the second in a series of papers describing the optimal design method for a digital human-computer interface of nuclear power plant (Npp) from three different points based on human reliability. The purpose of this series is to explore different optimization methods from varying perspectives. This present paper mainly discusses the optimal design method for quantity of components of the same factor. In monitoring process, quantity of components has brought heavy burden to operators, thus, human errors are easily triggered. To solve the problem, the authors propose an optimization process, a quick convergence search method and an affinity error probability mapping function. Two balanceable parameter values of the affinity error probability function are obtained by experiments. The experimental results show that the affinity error probability mapping function about human-computer interface has very good sensitivity and stability, and that quick convergence search method for fuzzy segments divided by component quantity has better performance than general algorithm.

  6. Regulatory Experience of the Embedded Digital Devices for Safety I and C Systems on Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y. M.; Lee, H. K.; Park, H. S. [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-10-15

    Conventional I and C(Instrumentation and Control) systems are tend to becoming unavailable and being replaced by smart equipment. These smart equipment is usually called embedded digital devices (EDDs) or industrial digital devices of limited functionality. Usually, some of these devices are found embedded in plant equipment such as sensing instrumentation, motors, pumps, actuators and breakers. They typically have a micro-processor, RAM, communication interface, a power source, etc. The U.S. Nuclear Regulatory Commission (US NRC) is concerning that these EDDs might exist in procured equipment used in safety systems without the devices having been explicitly identified in procurement documentation. This paper addresses the regulatory experiences of KINS of the EDDs for safety I and C systems and the future works for them. In this paper, we showed regulatory experiences of EDDs which used for safety grade equipment. EDDs might exist in safety grade procured equipment without explicit identification. Undetected defects of EDDs might be the potential safety concerns. EDDs should meet certain specific requirements in order to be selected and used in safety I and C system. We have plan to develop technical positions for identification and qualifying them. The technical position will address, but may not be limited to, quality and reliability, CCFs via software errors, EMC, and CGID for EDDs.

  7. Digital redesign of anti-wind-up controller for cascaded analog system.

    Science.gov (United States)

    Chen, Y S; Tsai, J S H; Shieh, L S; Moussighi, M M

    2003-01-01

    The cascaded conventional anti-wind-up (CAW) design method for integral controller is discussed. Then, the prediction-based digital redesign methodology is utilized to find the new pulse amplitude modulated (PAM) digital controller for effective digital control of the analog plant with input saturation constraint. The desired digital controller is determined from existing or pre-designed CAW analog controller. The proposed method provides a novel methodology for indirect digital design of a continuous-time unity output-feedback system with a cascaded analog controller as in the case of PID controllers for industrial control processes with the presence of actuator saturations. It enables us to implement an existing or pre-designed cascaded CAW analog controller via a digital controller effectively.

  8. Bus-oriented digital control techniques in nuclear power plants

    International Nuclear Information System (INIS)

    Salm, M.

    1987-01-01

    The author states the conservative principles which govern the authorization procedures for nuclear reactor control systems. Using the example of a feedwater supply regulator, employing a digital, bus-oriented control system, he describes how the stigma attached to the word nuclear can be alleviated. (G.T.H.)

  9. Simulation study of a system for diagnosis of nuclear power plant operation

    International Nuclear Information System (INIS)

    Wakabayashi, J.; Fukumoto, A.

    1981-01-01

    A diagnostic system of the nuclear power plant operation is proposed and the applicability of this system to the actual plant has been verified by computer simulation. A typical pressurized water reactor plant simulator was made by an analog computer and the diagnostic system was made by a digital computer. The observed signals obtained from the actual plant are simulated by superposing the equivalent observation noises generated by the digital computer on the sampled signals obtained from the plant simulator. 8 refs

  10. Verification experiment on the downblending of high enriched uranium (HEU) at the Portsmouth Gaseous Diffusion Plant. Digital video surveillance of the HEU feed stations

    International Nuclear Information System (INIS)

    Martinez, R.L.; Tolk, K.; Whiting, N.; Castleberry, K.; Lenarduzzi, R.

    1998-01-01

    As part of a Safeguards Agreement between the US and the International Atomic Energy Agency (IAEA), the Portsmouth Gaseous Diffusion Plant, Piketon, Ohio, was added to the list of facilities eligible for the application of IAEA safeguards. Currently, the facility is in the process of downblending excess inventory of HEU to low enriched uranium (LEU) from US defense related programs for commercial use. An agreement was reached between the US and the IAEA that would allow the IAEA to conduct an independent verification experiment at the Portsmouth facility, resulting in the confirmation that the HEU was in fact downblended. The experiment provided an opportunity for the DOE laboratories to recommend solutions/measures for new IAEA safeguards applications. One of the measures recommended by Sandia National Laboratories (SNL), and selected by the IAEA, was a digital video surveillance system for monitoring activity at the HEU feed stations. This paper describes the SNL implementation of the digital video system and its integration with the Load Cell Based Weighing System (LCBWS) from Oak Ridge National Laboratory (ORNL). The implementation was based on commercially available technology that also satisfied IAEA criteria for tamper protection and data authentication. The core of the Portsmouth digital video surveillance system was based on two Digital Camera Modules (DMC-14) from Neumann Consultants, Germany

  11. Development of regulatory guidance for risk-informing digital system reviews

    International Nuclear Information System (INIS)

    Arndt, S. A.

    2006-01-01

    In 1995, the U.S. Nuclear Regulatory Commission (NRC) issued the Probabilistic Risk Assessment (PRA) Policy Statement, which encourages the increased use of PRA and associated analyses in all regulatory matters to the extent supported by the state-of-the-art in PRA and the data. This policy applies, in part, to the review of digital systems, which offer the potential to improve plant safety and reliability through such features as increased hardware reliability and stability and improved failure detection capability. However, there are presently no universally accepted methods for modeling digital systems in current-generation PRAs. Further, there are ongoing debates among the PRA technical community regarding the level of detail that any digital system reliability model must have to adequately model the complex system interactions that can contribute to digital system failure modes. Moreover, for PRA modeling of digital reactor protection and control systems, direct interactions between system components and indirect interactions through controlled/supervised plant processes may necessitate the use of dynamic PRA methodologies. This situation has led the NRC to consider developing performance based rather than prescriptive regulatory guidance in this area. This paper will discuss the development of this guidance and some preliminary concepts. (authors)

  12. Investigations on the change of texture of plant cells due to preservative treatments by digital holographic microscopy

    Science.gov (United States)

    Vora, Priyanka; Anand, Arun

    2014-10-01

    Texture change is observed in preserved fruits and vegetables. Responsible factors for texture change during preservative treatments are cell morphology, cell wall structure, cell turger, water content and some biochemical components, and also the environmental conditions. Digital Holographic microscopy (DHM) is a quantitative phase contrast imaging technique, which provides three dimensional optical thickness profiles of transparent specimen. Using DHM the morphology of plant cells preserved by refrigeration or stored in vinegar or in sodium chloride can be obtained. This information about the spatio-temporal evolution of optical volume and thickness can be an important tool in area of food processing. Also from the three dimensional images, the texture of the cell can be retrieved and can be investigated under varying conditions.

  13. Standards for digital computers used in non-safety nuclear power plant applications: objectives and limitations

    International Nuclear Information System (INIS)

    Rorer, D.C.; Long, A.B.

    1977-01-01

    There are currently a number of efforts to develop standards which would apply to digital computers used in nuclear power plants for functions other than those directly involving plant protection (for example, ANS: 4.3.3 Subworking Group in the U.S., IEC 45A/WGA1 Subcommittee in Europe). The impetus for this activity is discussed and generally attributed to the realization that nonsafety systems computers may affect the assumptions used as the design bases for safety systems, the sizable economic loss which can result from the failure of a critical computer application, and the lingering concern about the misapplication of a still-new technology. At the same time, it is pointed out that these standards may create additional obstacles for the use of this new technology which are not present in the application of more conventional instrumentation and control equipment. Much of the U.S. effort has been directed toward the problem of validation of computer systems in which the potential exists for unplanned interactions between various functions in a multiprogram environment, using common hardware in a time-sharing mode. The goal is to develop procedures for the specification, development implementation, and documentation of testable, modular systems which, in the absence of proven quantitative techniques for assessing software reliability, are felt to provide reasonable assurance that the computer system will function as planned

  14. Development of digital device based work verification system for cooperation between main control room operators and field workers in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Min, E-mail: jewellee@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Hyun Chul, E-mail: leehc@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Ha, Jun Su, E-mail: junsu.ha@kustar.ac.ae [Department of Nuclear Engineering, Khalifa University of Science Technology and Research, Abu Dhabi P.O. Box 127788 (United Arab Emirates); Seong, Poong Hyun, E-mail: phseong@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)

    2016-10-15

    Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires

  15. Development of digital device based work verification system for cooperation between main control room operators and field workers in nuclear power plants

    International Nuclear Information System (INIS)

    Lee, Seung Min; Lee, Hyun Chul; Ha, Jun Su; Seong, Poong Hyun

    2016-01-01

    Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires

  16. Guidance and methodologies for managing digital instrumentation and control obsolescence

    International Nuclear Information System (INIS)

    O'Connor, Matthew; Geddes, Bruce; Kelley, Sean

    2015-01-01

    New nuclear plant technology will rely heavily, if not exclusively, on digital equipment. Obsolescence of digital I and C equipment is an inevitable part of plant technology life cycle for new and existing plants. Developing an overall strategic plan can mitigate some of the risks associated with obsolescence. Moreover, when developed as part of an overall lifecycle management plan (LCMP), a strategic obsolescence management approach can identify steps that can be taken at early stages of the technology life cycle to cope proactively with the obsolescence of equipment. Recent work within the Advanced Nuclear Technology (ANT) program at the Electric Power Research Institute (EPRI) has developed guidance and methodologies for determining when digital obsolescence is likely to occur, the extent to which it can occur, the risks and impacts due to obsolescence, and strategies that can be used to minimize its effects, all in the context of system lifecycle management planning (LCMP). Worksheets for assessing obsolescence risks and the applicability and limitations of management strategies were developed as part of this work, and can be used to create or supplement a strategic obsolescence management plan. (author)

  17. Quantitative risk assessment of digitalized safety systems

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sung Min; Lee, Sang Hun; Kang, Hym Gook [KAIST, Daejeon (Korea, Republic of); Lee, Seung Jun [UNIST, Ulasn (Korea, Republic of)

    2016-05-15

    A report published by the U.S. National Research Council indicates that appropriate methods for assessing reliability are key to establishing the acceptability of digital instrumentation and control (I and C) systems in safety-critical plants such as NPPs. Since the release of this issue, the methodology for the probabilistic safety assessment (PSA) of digital I and C systems has been studied. However, there is still no widely accepted method. Kang and Sung found three critical factors for safety assessment of digital systems: detection coverage of fault-tolerant techniques, software reliability quantification, and network communication risk. In reality the various factors composing digitalized I and C systems are not independent of each other but rather closely connected. Thus, from a macro point of view, a method that can integrate risk factors with different characteristics needs to be considered together with the micro approaches to address the challenges facing each factor.

  18. Identificación y control de un Vehículo Aéreo no Tripulado tipo Quadcopter

    Directory of Open Access Journals (Sweden)

    Eduardo Giraldo Suarez

    2017-02-01

    Full Text Available En este artículo se describe el modelo dinámico de un vehículo aéreo no tripulado tipo QuadCopter, se linealiza alrededor de un punto de operación y se aplica un controlador por realimentación de estados que logra llevar el sistema a un estado estable en 100ms. Se aplica un algoritmo de identificación MIMO por mínimos cuadrados al modelo no linealizado obteniendo un error medio cuadrático de 0.2562 grados en una simulación de 50s; se aplica un controlador LQR que logra controlar e identificar el sistema inicial en un tiempo de 3.7s y se compara con un controlador PID convencional obteniendo como resultado un menor tiempo de establecimiento y mejor seguimiento de referencia en el controlador LQR.

  19. An approach based on defense-in-depth and diversity (3D) for the reliability assessment of digital instrument and control systems of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Paulo Adriano da; Saldanha, Pedro L.C., E-mail: pasilva@cnen.gov.b, E-mail: Saldanha@cnen.gov.b [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil). Coord. Geral de Reatores Nucleares; Melo, Paulo F. Frutuoso e, E-mail: frutuoso@nuclear.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao em Engenharia. Programa de Engenharia Nuclear; Araujo, Ademir L. de [Associacao Brasileira de Ensino Universitario (UNIABEU), Angra dos Reis, RJ (Brazil)

    2011-07-01

    The adoption of instrumentation and control (I and C) digital technology has been slower in nuclear power plants. The reason has been unfruitful efforts to obtain evidence in order to prove that I and C systems can be used in nuclear safety systems, for example, the Reactor Protection System (RPS), ensuring the proper operation of all its functions. This technology offers a potential improvement for safety and reliability. However, there still no consensus about the model to be adopted for digital systems software to be used in reliability studies. This paper presents the 3D methodology approach to assess digital I and C reliability. It is based on the study of operational events occurring in NPPs. It is easy to identify, in general, the level of I and C system reliability, showing its key vulnerabilities, enabling to trace regulatory actions to minimize or avoid them. This approach makes it possible to identify the main types of digital I and C system failure, with the potential for common cause failures as well as evaluating the dominant failure modes. The MAFIC-D software was developed to assist the implementation of the relationships between the reliability criteria, the analysis of relationships and data collection. The results obtained through this tool proved to be satisfactory and complete the process of regulatory decision-making from licensing I and C digital of NPPs and call still be used to monitor the performance of I and C digital post-licensing during the lifetime of the system, providing the basis for the elaboration of checklists of regulatory inspections. (author)

  20. An approach based on defense-in-depth and diversity (3D) for the reliability assessment of digital instrument and control systems of nuclear power plants

    International Nuclear Information System (INIS)

    Silva, Paulo Adriano da; Saldanha, Pedro L.C.

    2011-01-01

    The adoption of instrumentation and control (I and C) digital technology has been slower in nuclear power plants. The reason has been unfruitful efforts to obtain evidence in order to prove that I and C systems can be used in nuclear safety systems, for example, the Reactor Protection System (RPS), ensuring the proper operation of all its functions. This technology offers a potential improvement for safety and reliability. However, there still no consensus about the model to be adopted for digital systems software to be used in reliability studies. This paper presents the 3D methodology approach to assess digital I and C reliability. It is based on the study of operational events occurring in NPPs. It is easy to identify, in general, the level of I and C system reliability, showing its key vulnerabilities, enabling to trace regulatory actions to minimize or avoid them. This approach makes it possible to identify the main types of digital I and C system failure, with the potential for common cause failures as well as evaluating the dominant failure modes. The MAFIC-D software was developed to assist the implementation of the relationships between the reliability criteria, the analysis of relationships and data collection. The results obtained through this tool proved to be satisfactory and complete the process of regulatory decision-making from licensing I and C digital of NPPs and call still be used to monitor the performance of I and C digital post-licensing during the lifetime of the system, providing the basis for the elaboration of checklists of regulatory inspections. (author)

  1. Addressing the susceptibility of digital systems to electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1993-01-01

    This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a verification and validation (V ampersand V) program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate acceptance criteria to ensure that the circuit or system under test meets the recommended guidelines. V ampersand V should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation susceptibility attributable to EMI will be greatly reduced

  2. MODIFICACIONES EN UN FLUJO DE CARGA POR LA INCLUSIÓN DE UN CONTROLADOR UNIFICADO DE FLUJOS DE POTENCIA MODIFICAÇÕES EM UM FLUXO DE CARGA PELA INCLUSÃO DE UM CONTROLADOR UNIFICADO DE FLUXOS DE POTÊNCIA MODIFICATIONS ON A POWER FLOW DUE TO INCLUSION OF A UNIFIED POWER FLOW CONTROLLER

    Directory of Open Access Journals (Sweden)

    JUAN PABLO RIVERA

    2009-07-01

    Full Text Available El crecimiento de los sistemas de potencia y las condiciones de mercado dadas por los esquemas desregulados han evidenciado las limitantes técnicas y de operación que los sistemas eléctricos de potencia SEP tienen para abastecer la demanda bajo estrictas condiciones de seguridad, calidad de potencia y confiabilidad. Un controlador unificado de flujos de potencia UPFC (unified power flow controller es uno de los dispositivos de la tecnología FACTS (Flexible AC Transmission Systems que ofrece mayor versatilidad en términos de interacción con las variables de operación y control de un SEP y puede ser una solución óptima a las necesidades adicionales de control en un SEP moderno. Este trabajo presenta una formulación matemática y conceptual para la inclusión de un dispositivo UPFC en el análisis de flujos de carga en un SEP y una metodología para su inclusión en un software de flujos de carga en estado estable. Para validar la eficiencia de los modelos y métodos propuestos, se selecciona un sistema de potencia de prueba adecuado para ver los efectos esperados de la inclusión del UPFC en el sistema.O crescimento dos sistemas de potência e as condições de mercado dadas pelos esquemas desregulados evidenciaram as limitantes técnicas e de operação que os sistemas elétricos de potência SET têm para abastecer a demanda sob estritas condições de segurança, qualidade de potência e confiabilidade. Um controlador unificado de fluxos de potência UPFC (unified power flow controller é um dos dispositivos da tecnologia FACTS (flexible AC transmission systems que oferece maior versatilidade em termos de interação com as variáveis de operação e controle de um SET e pode ser uma solução ótima às necessidades adicionais de controle em um SET moderno. Este trabalho apresenta uma formulação matemática e conceptual para a inclusão de um dispositivo UPFC na análise de fluxos de carga em um SET e uma metodologia para sua

  3. Sistema híbrido neuro-evolutivo aplicado ao controle de um processo multivariável

    OpenAIRE

    Coelho, Leandro dos Santos; Mariani, Viviana Cocco

    2006-01-01

    Este artigo apresenta uma nova abordagem para o projeto de um controlador PID (proporcional, integral e derivativo) multivariável baseado em uma rede neural e um algoritmo genético. O projeto do controlador PID multivariável é dividido em três etapas distintas. Na primeira etapa, uma rede neural de funções radiais de base é utilizada para identificação do processo multivariável. Na segunda etapa, o projeto do controlador é realizado, de forma off-line, baseado na sintonia de ganhos do control...

  4. Digital Culture and Digital Library

    Directory of Open Access Journals (Sweden)

    Yalçın Yalçınkaya

    2016-12-01

    Full Text Available In this study; digital culture and digital library which have a vital connection with each other are examined together. The content of the research consists of the interaction of culture, information, digital culture, intellectual technologies, and digital library concepts. The study is an entry work to integrity of digital culture and digital library theories and aims to expand the symmetry. The purpose of the study is to emphasize the relation between the digital culture and digital library theories acting intersection of the subjects that are examined. Also the perspective of the study is based on examining the literature and analytical evaluation in both studies (digital culture and digital library. Within this context, the methodology of the study is essentially descriptive and has an attribute for the transmission and synthesis of distributed findings produced in the field of the research. According to the findings of the study results, digital culture is an inclusive term that describes the effects of intellectual technologies in the field of information and communication. Information becomes energy and the spectrum of the information is expanding in the vertical rise through the digital culture. In this context, the digital library appears as a new living space of a new environment. In essence, the digital library is information-oriented; has intellectual technology support and digital platform; is in a digital format; combines information resources and tools in relationship/communication/cooperation by connectedness, and also it is the dynamic face of the digital culture in time and space independence. Resolved with the study is that the digital libraries are active and effective in the formation of global knowing and/or mass wisdom in the process of digital culture.

  5. Comparison of electronic digital alarm dosimeter with TLD

    International Nuclear Information System (INIS)

    Kumar, Pankaj; Pandey, J.P.N.; Shinde, A M.; Purohit, R.G.; Sarkar, P.K.

    2012-01-01

    Control of exposure of radiation workers on day to day basis has been made easy by use of semiconductor based electronic digital dosimeter. Additional dose constraints of 10 mSv for occupational radiation workers have made it essential to use such type of digital personal monitoring devices. In addition to conventional ionisation chamber based direct reading dosimeters, additional 35 semiconductor based digital dosimeters model MGP DMC 2000 S were used for the monitoring of personal exposure of radiation workers in a spent fuel reprocessing plant. Though better least count and good performance over a wide range of dose rate are claimed by the manufacture, before making use of such dosimeter on large scale, validation of its performance is required to be checked. In this paper, an effort is made to determine the performance of digital dosimeters, by exposing these digital dosimeters in combination with TLDs at different radiation levels and obtained results were compared and analysed

  6. Reliability analysis of digital safety systems at nuclear power plants

    International Nuclear Information System (INIS)

    Sopira Vladimir; Kovacs, Zoltan

    2015-01-01

    Reliability analysis of digital reactor protection systems built on the basis of TELEPERM XS is described, and experience gained by the Slovak RELKO company during the past 20 years in this domain is highlighted. (orig.)

  7. Modernization of control system using the digital control system

    International Nuclear Information System (INIS)

    Carrasco, J. A.; Fernandez, L.; Jimenez, A.

    2002-01-01

    Nowadays, all plant automation tendencies are based on the use of Digital Control System. In big industrial plants the control systems employed are Distributed Control Systems (DCS). The addition of these systems in nuclear power plants,implies an important adaptation process, because most of them were installed using analog control systems. This paper presents the objectives and the first results obtained, in a modernization project, focused in obtaining an engineering platform for making test and analysis of changes prior to their implementation in a nuclear plant. Modernization, Upgrade, DCS, Automation, Simulation, Training. (Author)

  8. A Cyber Security Self-Assessment Method for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Glantz, Clifford S.; Coles, Garill A.; Bass, Robert B.

    2004-11-01

    A cyber security self-assessment method (the Method) has been developed by Pacific Northwest National Laboratory. The development of the Method was sponsored and directed by the U.S. Nuclear Regulatory Commission. Members of the Nuclear Energy Institute Cyber Security Task Force also played a substantial role in developing the Method. The Method's structured approach guides nuclear power plants in scrutinizing their digital systems, assessing the potential consequences to the plant of a cyber exploitation, identifying vulnerabilities, estimating cyber security risks, and adopting cost-effective protective measures. The focus of the Method is on critical digital assets. A critical digital asset is a digital device or system that plays a role in the operation, maintenance, or proper functioning of a critical system (i.e., a plant system that can impact safety, security, or emergency preparedness). A critical digital asset may have a direct or indirect connection to a critical system. Direct connections include both wired and wireless communication pathways. Indirect connections include sneaker-net pathways by which software or data are manually transferred from one digital device to another. An indirect connection also may involve the use of instructions or data stored on a critical digital asset to make adjustments to a critical system. The cyber security self-assessment begins with the formation of an assessment team, and is followed by a six-stage process.

  9. A Cyber Security Self-Assessment Method for Nuclear Power Plants

    International Nuclear Information System (INIS)

    Glantz, Clifford S.; Coles, Garill A.; Bass, Robert B.

    2004-01-01

    A cyber security self-assessment method (the Method) has been developed by Pacific Northwest National Laboratory. The development of the Method was sponsored and directed by the U.S. Nuclear Regulatory Commission. Members of the Nuclear Energy Institute Cyber Security Task Force also played a substantial role in developing the Method. The Method's structured approach guides nuclear power plants in scrutinizing their digital systems, assessing the potential consequences to the plant of a cyber exploitation, identifying vulnerabilities, estimating cyber security risks, and adopting cost-effective protective measures. The focus of the Method is on critical digital assets. A critical digital asset is a digital device or system that plays a role in the operation, maintenance, or proper functioning of a critical system (i.e., a plant system that can impact safety, security, or emergency preparedness). A critical digital asset may have a direct or indirect connection to a critical system. Direct connections include both wired and wireless communication pathways. Indirect connections include sneaker-net pathways by which software or data are manually transferred from one digital device to another. An indirect connection also may involve the use of instructions or data stored on a critical digital asset to make adjustments to a critical system. The cyber security self-assessment begins with the formation of an assessment team, and is followed by a six-stage process

  10. Investigation of Classification and Design Requirements for Digital Software for Advanced Research Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Park, Gee Young; Jung, H. S.; Ryu, J. S.; Park, C

    2005-06-15

    As the digital technology is being developed drastically, it is being applied to various industrial instrumentation and control (I and C) fields. In the nuclear power plants, I and C systems are also being installed by digital systems replacing their corresponding analog systems installed previously. There had been I and C systems constructed by analog technology especially for the reactor protection system in the research reactor HANARO. Parallel to the pace of the current trend for digital technology, it is desirable that all I and C systems including the safety critical and non-safety systems in an advanced research reactor is to be installed based on the computer based system. There are many attractable features in using digital systems against existing analog systems in that the digital system has a superior performance for a function and it is more flexible than the analog system. And any fruit gained from the newly developed digital technology can be easily incorporated into the existing digital system and hence, the performance improvement of a computer based system can be implemented conveniently and promptly. Moreover, the capability of high integrity in electronic circuits reduces the electronic components needed to construct the processing device and makes the electronic board simple, and this fact reveals that the hardware failure itself are unlikely to occur in the electronic device other than some electric problems. Balanced the fact mentioned above are the roles and related issues of the software loaded on the digital integrated hardware. Some defects in the course of software development might induce a severe damage on the computer system and plant systems and therefore it is obvious that comprehensive and deep considerations are to be placed on the development of the software in the design of I and C system for use in an advanced research reactor. The work investigates the domestic and international standards on the classifications of digital

  11. Utility of low-order linear nuclear-power-plant models in plant diagnostics and control

    International Nuclear Information System (INIS)

    Tylee, J.L.

    1981-01-01

    A low-order, linear model of a pressurized water reactor (PWR) plant is described and evaluated. The model consists of 23 linear, first-order difference equations and simulates all subsystems of both the primary and secondary sides of the plant. Comparisons between the calculated model response and available test data show the model to be an adequate representation of the actual plant dynamics. Suggested use for the model in an on-line digital plant diagnostics and control system are presented

  12. Digital Collections, Digital Libraries & the Digitization of Cultural Heritage Information.

    Science.gov (United States)

    Lynch, Clifford

    2002-01-01

    Discusses digital collections and digital libraries. Topics include broadband availability; digital rights protection; content, both non-profit and commercial; digitization of cultural content; sustainability; metadata harvesting protocol; infrastructure; authorship; linking multiple resources; data mining; digitization of reference works;…

  13. H. Sapiens Digital: From Digital Immigrants and Digital Natives to Digital Wisdom

    Science.gov (United States)

    Prensky, Marc

    2009-01-01

    As we move further into the 21st century, the digital native/digital immigrant paradigm created by Marc Prensky in 2001 is becoming less relevant. In this article, Prensky suggests that we should focus instead on the development of what he calls "digital wisdom." Arguing that digital technology can make us not just smarter but truly wiser, Prensky…

  14. Digital Collections, Digital Libraries and the Digitization of Cultural Heritage Information.

    Science.gov (United States)

    Lynch, Clifford

    2002-01-01

    Discusses the development of digital collections and digital libraries. Topics include digitization of cultural heritage information; broadband issues; lack of compelling content; training issues; types of materials being digitized; sustainability; digital preservation; infrastructure; digital images; data mining; and future possibilities for…

  15. Development of test platform for digital I and C system evaluation

    International Nuclear Information System (INIS)

    Kim, Young Mi; Kwon, Yong Il

    2012-01-01

    Nuclear I and C (Instrument and Control) systems which need safety critical function have adopted various control units and communication protocols. These trends have been enlarged new nuclear plants design and upgrading of operating plants. Applying to these digital technologies to nuclear power plants has many good advantages, such as upgrade of functionality and performance and improvement of efficiency and economics. But, it also has several flaws. System designs have been more complicated and software reliability analysis and risk analysis have been more difficult. Also, cyber security problems came to the fore as I and C systems are connected through networks. The vulnerabilities of computer systems are vital to nuclear safety. Coping with the new IT technology of new and operating power plants, it is necessary to analyze verification technology and obtain regulatory technology through establishment of test platform. This paper presents test platform for digital I and C system evaluation of NPP

  16. Development of test platform for digital I and C system evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Mi; Kwon, Yong Il [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2012-10-15

    Nuclear I and C (Instrument and Control) systems which need safety critical function have adopted various control units and communication protocols. These trends have been enlarged new nuclear plants design and upgrading of operating plants. Applying to these digital technologies to nuclear power plants has many good advantages, such as upgrade of functionality and performance and improvement of efficiency and economics. But, it also has several flaws. System designs have been more complicated and software reliability analysis and risk analysis have been more difficult. Also, cyber security problems came to the fore as I and C systems are connected through networks. The vulnerabilities of computer systems are vital to nuclear safety. Coping with the new IT technology of new and operating power plants, it is necessary to analyze verification technology and obtain regulatory technology through establishment of test platform. This paper presents test platform for digital I and C system evaluation of NPP.

  17. Practical experience with digital I and C retrofit projects gathered by independent experts

    International Nuclear Information System (INIS)

    Zeck, Kurt; Schildheuer, Reinhard; Weich, Alfred

    2005-01-01

    As independent experts, we have accompanied a series of major projects where plant control systems have been retrofitted with digital I and C technology. As General Expert Inspectors of our authority, we have investigated, inspected and certified such projects - from defining the tasks at hand trough planning, approving, implementing and commissioning down to the regular operation of the equipment. Our special focus has been on the proper adherence to the relevant safety issues in nuclear plants in accordance with the current state-of-the-art in science and technology, and to the applicable codes of practice. In September 2004, at the international 'Nuclear Plant Instrumentation, Control and Human Machine Interface Technology' meeting in Columbus/Ohio, we presented some major retrofit projects and reported about how we, as independent official experts, accompany and monitor the activities of retrofitting plants with advanced digital safety I and C equipment, from the safety point of view. With current report, we would like to provide more detailed information about the practical experience gained with digital safety I and C retrofits and the conclusions drawn for currently ongoing retrofit projects. We will look at both the technical and licensing aspects of implementing such projects

  18. Recent control and instrumentation systems for BWR nuclear power plant

    International Nuclear Information System (INIS)

    Fujii, Hiroaki; Higashikawa, Yuichi; Sato, Hideyuki

    1990-01-01

    For the needs of the more stable operation of nuclear power stations, the upgrading of the measurement and control system for BWRs has been promoted by positively introducing remarkably advancing electronic technology. Further, it is aimed at to construct the synthetic digitized measurement and control system for nuclear power stations to heighten the operation reliability in ABWRs. As the first step of the development in the synthetic digitization, the monitoring and control system for radioactive waste treatment was put in practical use for No.5 plant of Kashiwazaki, Kariwa Nuclear Power Station, Tokyo Electric Power Co., Inc. Hitachi Ltd. has promoted the development and the application to actual plants of the measurement and control system for BWRs, in which digital control technology, optical information transmission technology and the operation-supporting technology using a computer were utilized. Hereafter, it is intended to expand the application of digital measurement and control aiming at improving the reliability, operation performance and maintainability. The nuclear power plant control complex with advanced man-machine interface-90 (NUCAMM-90) was developed, and its application to actual plants is planned. (K.I.)

  19. Control de velocidad de una estera transportadora de caña con un controlador difuso; Speed Control of Sugar Cane Belt Conveyer with Fuzzy Controller

    Directory of Open Access Journals (Sweden)

    Ariel Domínguez Cardosa

    2011-02-01

    Full Text Available Se describen las experiencias de los autores en el diseño de un controlador difuso para el control de velocidad deun motor de inducción en coordenadas de campo, que acciona una estera transportadora de caña, sin la necesidadde realizar las compensaciones en los ejes d-q, lo que simplifica sustancialmente el control. El controladordifuso implementado es del tipo Mamdani y utiliza como variables de entrada el error de la velocidad y el cambiodel error de la velocidad, y como variable de salida la corriente de mando del eje q. Para el desemborronado seempleó el método del centro de gravedad. Los resultados alcanzados muestran que el comportamiento delsistema de control sometido a cambios bruscos de carga y referencia son superiores a los obtenidos con un PIDclásico.  This paper describes the experience obtained by the authors in the design of a fuzzy controller for speed controlof an induction motor in field oriented, that drives a sugar cane belt conveyor, without carrying out the compensationsin the d-q axes. The Mamdani type fuzzy controller was implemented using speed error and the rate ofchange of the speed error as input variables and the current component in the q-axis as output variable. Thesimulation results reached show that the behaviour of the control system under suddenly load and referencechanges are better than those results obtained using PID classic.

  20. Improvement of the characterization of ultrasonic data by means of digital signal processing

    International Nuclear Information System (INIS)

    Bieth, M.; Romy, D.; Weigel, D.

    1985-01-01

    The digital signal processing method for averaging using minima developed by Framatome allows to improve signal-to-noise ratio up to 7 dB during ultrasonic testing of cast stainless steel structures (primary pipes of PWR power plants). Application of digital signal processing to industrial testing conditions requires the availability of a fast analog-digital converter capable of real time processings which has been developed by CGR [fr

  1. Application of digital solutions to help the safe and efficient operation of nuclear power plants; Aplicacion de soluciones digitales para la ayuda a la operacion segura y eficiente de las centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Ortega P, F.; Fernandez F, S., E-mail: fortega@tecnatom.es [Tecnatom S. A., Av. Montes de Oca 1, 28703 San Sebastian de los Reyes, Madrid (Spain)

    2017-09-15

    In the search for excellence, the emergence of solutions to digitize nuclear power plants is an opportunity to optimize the operation and safety of them. The new technologies available today in the market, applied under a global vision of the operation, can contribute to the excellent operation of nuclear power plants in terms of efficiency and effectiveness. Tecnatom has a long experience in various areas related to the operation of the plants, giving the aforementioned global vision, essential to develop global solutions that pursue the safe and efficient operation of the operation. (Author)

  2. Digital technology strengthens EDF's nuclear safety

    International Nuclear Information System (INIS)

    Dupin, Ludovic

    2016-01-01

    This article proposes an overview of the development of the use of various and new digital technologies of information and communication by EDF to train its nuclear operators, field technicians who are maintaining nuclear power plants, personnel in charge of risk management, and so on. Trainees are using tablets with augmented reality software, serious games, virtual reality helmets, and also digital simulators to learn how to control a reactor. More practical training also exists: people are taught how to practically and correctly assemble tubes for example

  3. Safety and security analysis for distributed control system in nuclear power plants

    International Nuclear Information System (INIS)

    Lu Zhigang; Liu Baoxu

    2011-01-01

    The Digital Distributed Control System (DCS) is the core that manages all monitoring and operation tasks in a Nuclear Power Plant (NPP). So, Digital Distributed Control System in Nuclear Power Plant has strict requirements for control and automation device safety and security due to many factors. In this article, factors of safety are analyzed firstly, while placing top priority on reliability, quality of supply and stability have also been carefully considered. In particular, advanced digital and electronic technologies are adopted to maintain sufficient reliability and supervisory capabilities in nuclear power plants. Then, security of networking and information technology have been remarked, several design methodologies considering the security characteristics are suggested. Methods and technologies of this article are being used in testing and evaluation for a real implement of a nuclear power plant in China. (author)

  4. Use of an automated digital images system for detecting plant status changes in response to climate change manipulations

    Science.gov (United States)

    Cesaraccio, Carla; Piga, Alessandra; Ventura, Andrea; Arca, Angelo; Duce, Pierpaolo

    2014-05-01

    climate manipulations: control (no manipulation), warming (overnight cover), and drought (interception of the periodic precipitation) treatments (36 shots x panorama (3 rows x 12 columns) with a degree of overlapping equal to 30%). On each panorama, ROIs (Regions of Interest) focusing major species of the shrubland ecosystem were identified. Then, image analysis was performed to obtain information on vegetation status (i.e. color signals and phenology). The color channel information (digital numbers; DNs) were extracted from the RAW file. The overall brightness (i.e., total RGB DN, green excess index) was also calculated. Finally, the RGB value was correlated with the pattern of phenological development. Preliminary results of this study show that the use of digital images are well-suited to identify phenological pattern of the Mediterranean species. Results of digital images analysis can be a valuable support for ecologists, environmental scientists, and land managers providing information useful to interpret phenological responses of plants to climate change, to validate satellite-based phenology data, and to provide input to adaption strategies plans to climate change.

  5. Electronic plants

    Science.gov (United States)

    Stavrinidou, Eleni; Gabrielsson, Roger; Gomez, Eliot; Crispin, Xavier; Nilsson, Ove; Simon, Daniel T.; Berggren, Magnus

    2015-01-01

    The roots, stems, leaves, and vascular circuitry of higher plants are responsible for conveying the chemical signals that regulate growth and functions. From a certain perspective, these features are analogous to the contacts, interconnections, devices, and wires of discrete and integrated electronic circuits. Although many attempts have been made to augment plant function with electroactive materials, plants’ “circuitry” has never been directly merged with electronics. We report analog and digital organic electronic circuits and devices manufactured in living plants. The four key components of a circuit have been achieved using the xylem, leaves, veins, and signals of the plant as the template and integral part of the circuit elements and functions. With integrated and distributed electronics in plants, one can envisage a range of applications including precision recording and regulation of physiology, energy harvesting from photosynthesis, and alternatives to genetic modification for plant optimization. PMID:26702448

  6. SCAN- a maintenance-free flowrate meter with direct digital read-out for computerised control applications in radiochemical plants

    Energy Technology Data Exchange (ETDEWEB)

    Shah, B V; Siddiqui, I A; Theyyunni, T K [Process Engineering and Systems Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    In radiochemical plants, the choice of flowrate sensor is subject to stringent requirements of fail-safe design and freedom from maintenance. The SCAN remote digital direct indicating flowrate meter described in this paper was developed to meet the requirements of flowrate and transmitting it to the control room, and to a computerised control system. SCAN is designed on the principle that flowrate through an orifice is a function of the head of liquid acting upon it. SCAN consists of a small chamber which receives the flow, and discharges it through an orifice located in bottom. The level of liquid in the pot represents the flowrate of the input stream. SCAN has been developed into an accurate, rugged and practical device by refinements in the design of internals, and by introducing a special end-section which makes the calibration insensitive to location. An important feature of SCAN is that it is passive, maintenance free, fail-safe device and contains no moving parts. There is no liquid hold up in the SCAN when idle, which is a desirable feature for the radiochemical plant environment. (author). 3 figs., 2 tabs.

  7. Impacts of Digital Imaging versus Drawing on Student Learning in Undergraduate Biodiversity Labs

    Science.gov (United States)

    Basey, John M.; Maines, Anastasia P.; Francis, Clinton D.; Melbourne, Brett

    2014-01-01

    We examined the effects of documenting observations with digital imaging versus hand drawing in inquiry-based college biodiversity labs. Plant biodiversity labs were divided into two treatments, digital imaging (N = 221) and hand drawing (N = 238). Graduate-student teaching assistants (N = 24) taught one class in each treatment. Assessments…

  8. Digital Humanities and networked digital media

    DEFF Research Database (Denmark)

    Finnemann, Niels Ole

    2014-01-01

    This article discusses digital humanities and the growing diversity of digital media, digital materials and digital methods. The first section describes the humanities computing tradition formed around the interpretation of computation as a rule-based process connected to a concept of digital...... materials centred on the digitisation of non-digital, finite works, corpora and oeuvres. The second section discusses “the big tent” of contemporary digital humanities. It is argued that there can be no unifying interpretation of digital humanities above the level of studying digital materials with the help...... of software-supported methods. This is so, in part, because of the complexity of the world and, in part, because digital media remain open to the projection of new epistemologies onto the functional architecture of these media. The third section discusses the heterogeneous character of digital materials...

  9. Experience with digital acoustic monitoring systems for PWRs and BWRs

    International Nuclear Information System (INIS)

    Olma, B.J.

    1998-01-01

    Substantial progress could be reached both in system technics and in application of digital acoustic monitoring systems for assessing mechanical integrity of reactor primary systems. For the surveillance of PWRs and BWRs during power operation of the plants, acoustic signals of Loose Parts Monitoring System sensors are continuously monitored for signal bursts associated with metallic impacts. ISTec/GRS experience with its digital systems MEDEA and RAMSES has shown that acoustic signature analysis is very successful for detecting component failures at an early stage. Methods for trending and classification of digital burst signals are shown, experience with their practical use will be presented. (author)

  10. Digital control computer upgrade at the Cernavoda NPP simulator

    International Nuclear Information System (INIS)

    Ionescu, T.

    2006-01-01

    The Plant Process Computer equips some Nuclear Power Plants, like CANDU-600, with Centralized Control performed by an assembly of two computers known as Digital Control Computers (DCC) and working in parallel for safely driving of the plan at steady state and during normal maneuvers but also during abnormal transients when the plant is automatically steered to a safe state. The Centralized Control means both hardware and software with obligatory presence in the frame of the Full Scope Simulator and subject to changing its configuration with specific requirements during the plant and simulator life and covered by this subsection

  11. A study on the establishment of safety assessment guidelines of commercial grade item dedication in digitalized safety systems

    International Nuclear Information System (INIS)

    Hwang, H. S.; Kim, B. R.; Oh, S. H.

    1999-01-01

    Because of obsolescing the components used in safety related systems of nuclear power plants, decreasing the number of suppliers qualified for the nuclear QA program and increasing maintenance costs of them, utilities have been considering to use commercial grade digital computers as an alternative for resolving such issues. However, commercial digital computers use the embedded pre-existing software, including operating system software, which are not developed by using nuclear grade QA program. Thus, it is necessary for utilities to establish processes for dedicating digital commercial grade items. A regulatory body also needs guidance to evaluate the digital commercial products properly. This paper surveyed the regulations and their regulatory guides, which establish the requirements for commercial grade items dedication, industry standards and guidances applicable to safety related systems. This paper provides some guidelines to be applied in evaluating the safety of digital upgrades and new digital plant protection systems in Korea

  12. Digital control in nuclear power plants

    International Nuclear Information System (INIS)

    Bouzon, B.

    1984-01-01

    This document presents the latest automatic control structures used in the programmable control systems of 13.00 MW nuclear power plants constructed by Electricite de France. The impact of this technological innovation goes beyond a straightforward design modification; in addition to the new range of processes made possible, it permits far-reaching changes in the working method employed at the design office and in the field. (author)

  13. Development of Alarm System link Drawing for Operation Support for APR1400 Digital Main Control Room

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Hwan [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    Digitalized MMI(Man-Machine Interface) including Digital Main Control Room(MCR) and digital I and C system was being applied for SKN 3 and 4 Nuclear Power Plant(NPP) and subsequent APR1400 NPP type. But, operators can not easily find instrument for alarm immediately. Therefore, Alarm system is required to easily find instrument for Alarm. For this implementation, we will plan system design considering design feature without affecting network load and CPU load. We have developed Alarm system link drawing for digital MCR. Operators of the digitalized MCR navigates from their consoles to the drawings related to the plant alarms and their instruments or the operation status. Such method gives cognitive load to the operators having to travel to different locations in finding the related information. Screen Sharing System, which is the fundamental technique for Drawing Interconnection Alarm System is close to completion, and it should be functionally tested and verified by the human factor engineering. For the actual application to the operating plants, the drawings to be interconnected to the alarms and the opinions from the operators/maintenance departments for designating alarm number should be surveyed, Also, another function that allows the access to the alarm related drawings not only from the MCR but also from the other offices.

  14. Development of Alarm System link Drawing for Operation Support for APR1400 Digital Main Control Room

    International Nuclear Information System (INIS)

    Kim, Ki-Hwan

    2016-01-01

    Digitalized MMI(Man-Machine Interface) including Digital Main Control Room(MCR) and digital I and C system was being applied for SKN 3 and 4 Nuclear Power Plant(NPP) and subsequent APR1400 NPP type. But, operators can not easily find instrument for alarm immediately. Therefore, Alarm system is required to easily find instrument for Alarm. For this implementation, we will plan system design considering design feature without affecting network load and CPU load. We have developed Alarm system link drawing for digital MCR. Operators of the digitalized MCR navigates from their consoles to the drawings related to the plant alarms and their instruments or the operation status. Such method gives cognitive load to the operators having to travel to different locations in finding the related information. Screen Sharing System, which is the fundamental technique for Drawing Interconnection Alarm System is close to completion, and it should be functionally tested and verified by the human factor engineering. For the actual application to the operating plants, the drawings to be interconnected to the alarms and the opinions from the operators/maintenance departments for designating alarm number should be surveyed, Also, another function that allows the access to the alarm related drawings not only from the MCR but also from the other offices

  15. Digital Systems Security in the nuclear scope; Sistemas Digitales de Seguridad en el ambito nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Amado, I.

    2011-07-01

    Overall nuclear power plants and in particular the Spanish, work well, but to modernize and improve the operation of existing Spanish plants, perhaps the natural evolution is to use digital technologies.

  16. REVIEW OF NRC APPROVED DIGITAL CONTROL SYSTEMS ANALYSIS

    International Nuclear Information System (INIS)

    Markman, D.W.

    1999-01-01

    Preliminary design concepts for the proposed Subsurface Repository at Yucca Mountain indicate extensive reliance on modern, computer-based, digital control technologies. The purpose of this analysis is to investigate the degree to which the U. S. Nuclear Regulatory Commission (NRC) has accepted and approved the use of digital control technology for safety-related applications within the nuclear power industry. This analysis reviews cases of existing digitally-based control systems that have been approved by the NRC. These cases can serve as precedence for using similar types of digitally-based control technologies within the Subsurface Repository. While it is anticipated that the Yucca Mountain Project (YMP) will not contain control systems as complex as those required for a nuclear power plant, the review of these existing NRC approved applications will provide the YMP with valuable insight into the NRCs review process and design expectations for safety-related digital control systems. According to the YMP Compliance Program Guidance, portions of various NUREGS, Regulatory Guidelines, and nuclear IEEE standards the nuclear power plant safety related concept would be applied to some of the designs on a case-by-case basis. This analysis will consider key design methods, capabilities, successes, and important limitations or problems of selected control systems that have been approved for use in the Nuclear Power industry. An additional purpose of this analysis is to provide background information in support of further development of design criteria for the YMP. The scope and primary objectives of this analysis are to: (1) Identify and research the extent and precedence of digital control and remotely operated systems approved by the NRC for the nuclear power industry. Help provide a basis for using and relying on digital technologies for nuclear related safety critical applications. (2) Identify the basic control architecture and methods of key digital control

  17. Study on HRA-based method for assessing digital man-machine interface

    International Nuclear Information System (INIS)

    Li Pengcheng; Dai Licao; Zhang Li; Zhao Ming; Hu Hong

    2014-01-01

    In order to identify the design flaws of digital man-machine interface (MMI) that may trigger human errors or weaken the performance of operators, a HRA-based method (namely HCR + CREAM + HEC) for assessing digital MMI was established. Firstly, the HCR method was used to identify the risk scenarios of high human error probability from the overall event as a whole perspective. Then, for the identified high-risk scenarios, the CREAM was adopted to determine the various error modes and its error probability, and the failure probability was ranked. Finally, the human factors engineering checklist of digital MMI was established according to the characteristics of digital MMI, it was used to check the digital MMI with high error probability in order to identify the design flaws of digital MMI, and the suggestions of optimization were provided. The results show that the provided assessment method can quickly and efficiently identify the design flaws of digital MMI which easily trigger human errors, and the safety of operation of the digital control system for nuclear power plants can be enhanced by optimization of design. (authors)

  18. Adoption of digital safety protection system in Japan

    International Nuclear Information System (INIS)

    Ogiso, Z.

    1998-01-01

    The application of micro-processor-based digital controllers has been widely propagated among various industries in recent years. While in the nuclear power plant industry, the application of them has also been expanding gradually starting from non-safety related systems, taking advantage of their reliability and maintainability over the conventional analog devices. Based on the careful study of the feasibility of digital controllers to the safety protection system, the Tokyo Electric Power Company proposed on May 1989 the adoption of digital controllers to the safety protection system in the Application for Permission of Establishment of Kashiwazaki-Kariwa units 6 and 7 (ABWR-1350Mwe each). MITI, Ministry of International Trade and Industry, the Japanese regulatory body for electric power generating facilities, had approved this application after careful review. This paper describes a series of supporting activities leading to the MITI's approval of the digital safety protection system and the MITI's licensing activities. (author)

  19. Matlab/Simulink-based simulation for digital-control system of marine three-shaft gas-turbine

    International Nuclear Information System (INIS)

    Yu Youhong; Chen Lingen; Sun Fengrui; Wu Chih

    2005-01-01

    A gas-turbine plant model is required in order to design and develop its control system. In this paper, a simulation model of a marine three-shaft gas-turbine's digital-control system is presented. Acceleration processes are simulated via a Matlab/Simulink program. The effects of some of the main variables on the system's performance are analyzed and the optimum values of parameters obtained. A simulation experiment upon a real gas-turbine plant is performed using the digital-control model. The results show that the simulation model is reliable

  20. Digital broadcasting

    International Nuclear Information System (INIS)

    Park, Ji Hyeong

    1999-06-01

    This book contains twelve chapters, which deals with digitization of broadcast signal such as digital open, digitization of video signal and sound signal digitization of broadcasting equipment like DTPP and digital VTR, digitization of equipment to transmit such as digital STL, digital FPU and digital SNG, digitization of transmit about digital TV transmit and radio transmit, digital broadcasting system on necessity and advantage, digital broadcasting system abroad and Korea, digital broadcasting of outline, advantage of digital TV, ripple effect of digital broadcasting and consideration of digital broadcasting, ground wave digital broadcasting of DVB-T in Europe DTV in U.S.A and ISDB-T in Japan, HDTV broadcasting, satellite broadcasting, digital TV broadcasting in Korea, digital radio broadcasting and new broadcasting service.

  1. Defense-in-depth for common cause failure of nuclear power plant safety system software

    International Nuclear Information System (INIS)

    Tian Lu

    2012-01-01

    This paper briefly describes the development of digital I and C system in nuclear power plant, and analyses the viewpoints of NRC and other nuclear safety authorities on Software Common Cause Failure (SWCCF). In view of the SWCCF issue introduced by the digitized platform adopted in nuclear power plant safety system, this paper illustrated a diversified defence strategy for computer software and hardware. A diversified defence-in-depth solution is provided for digital safety system of nuclear power plant. Meanwhile, analysis on problems may be faced during application of nuclear safety license are analyzed, and direction of future nuclear safety I and C system development are put forward. (author)

  2. SISTEMA DE CONTROL INTELIGENTE PARA UN GRUPO DE ELEVADORES

    Directory of Open Access Journals (Sweden)

    Andrés Enrique Rosso Mateus

    2008-01-01

    Full Text Available En este artículo se trata el problema del tráfico vertical en edificios de gran altura y se describe el análisis, diseño y evaluación de un sistema de control para un grupo elevadores que busca mejorar el desempeño respecto a un sistema de control tradicional. El controlador propuesto busca asignar de una forma inteligente las llamadas que se generan a los ascensores que hacen parte del grupo, el desempeño del sistema se traduce en una reducción de los tiempos de servicio y de la energía que invierte el sistema. El controlador propuesto está basado en lógica difusa y las reglas de inferencia expresan el conocimiento de un experto orientado hacia la obtención de los objetivos mencionados. El controlador inteligente se evalúa en un simulador gráfico desarrollado para este fin, este simulador permite ingresar parámetros de configuración para que se adapte y represente una edificación real. Se corrieron dos simulaciones, una usando un controlador convencional y otra usando el controlador inteligente, esto con el fin de comparar su desempeño y cuantificar valores como tiempo de esperar de los usuarios y energía consumida por el sistema.

  3. A cell-to-cell Markovian model for the reliability of a digital control system of a steam generator

    International Nuclear Information System (INIS)

    Gomes, Ian B.; Melo, Paulo F.F. Frutuoso e; Saldanha, Pedro L.C.

    2013-01-01

    With the shift of technology from analog to digital systems, due to the obsolescence of the older analog systems and the functional advantages of the digital ones, existing nuclear power plants have begun to replace their systems, while newer plants use digital systems from the beginning of their construction. However, the process of risk-informed analysis for digital systems has not been satisfactorily developed yet. Traditional methods, such as fault trees, have limitations, while dynamic methods are still in the tests stage and may be difficult to be applied to a real size probabilistic safety assessment (PSA) model. The objective of this paper is to study and obtain a better comprehension of the Markov/CCMT method, a method that combines the traditional Markovian methodology with the cell-to-cell mapping technique for representing the possible failure events that can be originated in the dynamic interactions between the instrumentation and control system and the controlled process, and among the various components of the digital system. The study consists of the simulation of a digital water level control system of the steam generator of a PWR plant. From this simulation, a Failure Modes and Effects Analysis (FMEA) was made and the information obtained was used to calculate the system reliability, using the Markov/CCMT methodology. The results show that the method is capable of identifying the most probable causes for a possible failure of the digital system. (author)

  4. Digitization of natural objects with micro CT and photographs.

    Science.gov (United States)

    Ijiri, Takashi; Todo, Hideki; Hirabayashi, Akira; Kohiyama, Kenji; Dobashi, Yoshinori

    2018-01-01

    In this paper, we present a three-dimensional (3D) digitization technique for natural objects, such as insects and plants. The key idea is to combine X-ray computed tomography (CT) and photographs to obtain both complicated 3D shapes and surface textures of target specimens. We measure a specimen by using an X-ray CT device and a digital camera to obtain a CT volumetric image (volume) and multiple photographs. We then reconstruct a 3D model by segmenting the CT volume and generate a texture by projecting the photographs onto the model. To achieve this reconstruction, we introduce a technique for estimating a camera position for each photograph. We also present techniques for merging multiple textures generated from multiple photographs and recovering missing texture areas caused by occlusion. We illustrate the feasibility of our 3D digitization technique by digitizing 3D textured models of insects and flowers. The combination of X-ray CT and a digital camera makes it possible to successfully digitize specimens with complicated 3D structures accurately and allows us to browse both surface colors and internal structures.

  5. A New Digital Imaging and Analysis System for Plant and Ecosystem Phenological Studies

    Science.gov (United States)

    Ramirez, G.; Ramirez, G. A.; Vargas, S. A., Jr.; Luna, N. R.; Tweedie, C. E.

    2015-12-01

    Over the past decade, environmental scientists have increasingly used low-cost sensors and custom software to gather and analyze environmental data. Included in this trend has been the use of imagery from field-mounted static digital cameras. Published literature has highlighted the challenge scientists have encountered with poor and problematic camera performance and power consumption, limited data download and wireless communication options, general ruggedness of off the shelf camera solutions, and time consuming and hard-to-reproduce digital image analysis options. Data loggers and sensors are typically limited to data storage in situ (requiring manual downloading) and/or expensive data streaming options. Here we highlight the features and functionality of a newly invented camera/data logger system and coupled image analysis software suited to plant and ecosystem phenological studies (patent pending). The camera has resulted from several years of development and prototype testing supported by several grants funded by the US NSF. These inventions have several unique features and functionality and have been field tested in desert, arctic, and tropical rainforest ecosystems. The system can be used to acquire imagery/data from static and mobile platforms. Data is collected, preprocessed, and streamed to the cloud without the need of an external computer and can run for extended time periods. The camera module is capable of acquiring RGB, IR, and thermal (LWIR) data and storing it in a variety of formats including RAW. The system is full customizable with a wide variety of passive and smart sensors. The camera can be triggered by state conditions detected by sensors and/or select time intervals. The device includes USB, Wi-Fi, Bluetooth, serial, GSM, Ethernet, and Iridium connections and can be connected to commercial cloud servers such as Dropbox. The complementary image analysis software is compatible with all popular operating systems. Imagery can be viewed and

  6. Replacement of the control and instrumentation system with the microprocessor based systems in Japanese PWR plants

    International Nuclear Information System (INIS)

    Hayashi, N.

    1998-01-01

    In Ohi Units 3 and 4, Ikata Unit 3, and Genkai Units 3 and 4, the latest of PWR plants now under operation in Japan, the reactor control system and turbine control system employ the microprocessor base digital control systems with a view to improving reliability, operability and maintainability. In the next stage plants, another application of such digital system is also planned for the instrumentation rack for the reactor protection system for further improvement. On the other hand, in Mihama Unit 1, the first of domestic PWR plants, and later plants except for the latest 5 plants, analog control systems are employed for the instrumentation racks. For the analog control systems of these plants, FOXBORO H-Line instruments, equivalent domestic box type instruments or WH7300 Series card type instruments were initially employed, and later replaced with domestic card type control systems after 10-15 year operation. However, 8-12 years have passed since these replacements, so the 15th year generally quoted as an interval for replacing C and I systems is near at hand. This is the time to consider next replacement. This replacement will be based on the latest digital technology. However, it is not practical way for the existing plants to apply the same integrated digital C and I system configuration for the next stage plants, because it requires the drastic change of the C and I system configuration and significant cost-up. Therefore, we must investigate the optimum digital C and I system configuration for the existing system. (author)

  7. Reactor instrumentation and control in nuclear power plants in Germany

    International Nuclear Information System (INIS)

    Aleite, W.

    1993-01-01

    The pertinent legislation, guidelines and standards of importance for nuclear power plant construction as well as the relevant committees in Germany are covered. The impact of international developments on the German regulatory scene is mentioned. A series of 15 data sheets on reactor control, followed by 5 data sheets on instrumentation and control in nuclear power plants, which were drawn up for German plants, are compared and commented in some detail. Digitalization of instrumentation and control systems continues apace. To illustrate the results that can be achieved with a digitalized information system, a picture series that documents a plant test of behavior on simulated steam generator tube rupture is elaborately commented. An outlook on backfitting and upgrading applications concludes this paper. (orig.) [de

  8. PERSEPSI GURU TENTANG DIGITAL NATIVES, SUMBER BELAJAR DIGITAL DAN MOTIVASI MEMANFAATKAN SUMBER BELAJAR DIGITAL

    Directory of Open Access Journals (Sweden)

    Ferdinandus Bate Dopo

    2016-06-01

    TEACHER’S PERCEPTION OF DIGITAL NATIVES, DIGITAL LEARNING RESOURCES AND MOTIVATION TO UTILIZE DIGITAL LEARNING RESOURCES Abstract This study aims to reveal (1 the influence of teacher's perception of digital natives toward teacher’s motivation to utilize digital learning resources. (2 the influence of teacher's perception of digital learning resources toward teacher’s motivation to utilize digital learning resources and (3 the influence both of teacher's perception of digital natives and digital learning resources toward teacher’s motivation to utilize digital learning resources. This study used the descriptive-correlational quantitative approach. The Population and sample were high school teachers of Regina Pacis Bajawa, SMA Seminari Mataloko and SMA Negeri 1 Golewa. Sampling technique in this research was proportional random sampling. A questionnaire was used to obtain the data. The data were analyzed using the Likert scale. The instrument was developed based on lattice theory of assessment instruments relevant to the study variables. The analysis technique used is a regression followed by statistic technique of t test and F test with the significance level of 0.05. The results are as follows. (1 There is a positive and significant influence of teacher's perception of digital natives toward teacher’s motivation to utilize digital learning resources. (2 There is a positive and significant influence of teacher's perception of digital learning resources and teacher’s motivation to utilize digital learning resources. (3 There is a positive and significant influence both of teacher's perception of digital learning resources and teacher’s motivation to utilize digital learning resources. Keywords: perception, digital natives, digital learning resources, motivation

  9. Manufacture of Platform Prototype for Digital Safety System

    International Nuclear Information System (INIS)

    Lee, S. Y.; Kim, J. S.; Kim, J. M.

    2010-01-01

    Unit controller is a basic unit of digital safety system platform prototype. The typical unit controller is comprised of CPB(CPU board), CMB(communication board), AIB(Analog input board), AOB(Analog output board), CIB(contact input board), COB(contact output board), and a subrack. It is developed according to H/W development procedure and S/W development life cycle. A digital safety system(for example, plant protection system) is the assemblies of unit controllers. CPB performs the function of each system. DSP(digital signal processor) is built in CPB. CMB is responsible for communication between unit controllers. NSD(Network Switching Device) exchanges data between the unit controllers. Each unit controller of the platform are connected to NSD through CMB. Reliability analyses on unit controller and NSD are performed. These reliability data are used as input of technical validation

  10. Active and reactive power flow regulation for a grid connected vsc based on fuzzy controllers

    Directory of Open Access Journals (Sweden)

    Nelson Díaz Aldana

    2013-01-01

    bajo diferentes niveles de transferencia de potencia. Este artículo, presenta el análisis, diseño y resultados de la implementación de controladores difusos para la regulación del flujo de potencia activa y reactiva de un VSC conectado a red. Además, se muestra la dependencia de la respuesta transitoria y de estado estacionario con la forma de las funciones de pertenencia del controlador difuso cuando este se aplica a diferentes niveles de transferencia de potencia. El desempeño de los controladores se verifica mediante simulación y mediante implementación física en un prototipo construido de un VSC.

  11. Creativity Support to Improve Health-and-Safety in Manu-facturing Plants: Demonstrating Everyday Creativity

    OpenAIRE

    Zachos, K.; Maiden, N.; Levis, S.

    2015-01-01

    This paper reports the development and deployment of digi-tal support for human creativity in a domain outside of the creative industries -- health-and-safety management in man-ufacturing plants. It reports applied research to extend a risk detection and resolution process at a world-class manufac-turing plant that produces tractors with creativity techniques and new digital support for the plant employees to use these techniques effectively as part of the risk detection and reso-lution proce...

  12. Digital instrumentation and control - how not to do it

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    A report entitled ''Digital I and C systems in nuclear power plants: safety and reliability issues'' has been produced by the US National Research Council at the behest of the Nuclear Regulatory Commission (NRC). Phase 1 of the reported study identified eight key issues: software quality assurance; common-mode software failure potential; systems aspects of digital I and C technology; human factors and human-machine interfaces; safety and reliability assessment methods; dedication of commercial off-the-shelf hardware and software; a case-by-case licensing process; adequacy of technical infrastructure. These were addressed by considering the impact of digital I and C systems against a set of standard regulatory approaches to assessing and ensuring safety. Phase 2 dealt with the criteria for reviewing and approving digital I and C technology, the characterisation and evaluation of alternative approaches to licensing the technology, and guidelines for the NRC to license and regulate it. (UK)

  13. The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, J.M.; W. Gunther, G. Martinez-Guridi

    2010-02-26

    New and advanced reactors will use integrated digital instrumentation and control (I&C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I&C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I&C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I&C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I&C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I&C conditions as part of the design process and the HSI features and functions that support operators to monitor I&C performance and manage I&C degradations when they occur. In addition, we identified topics for future research.

  14. Digital Components in Swedish NPP Power Systems

    International Nuclear Information System (INIS)

    Karlsson, Mattias; Eriksson, Tage

    2015-01-01

    Swedish nuclear power plants have over the last 20 years of operation modernised or exchanged several systems and components of the electrical power system. Within these works, new components based on digital technology have been employed in order to realize functionality that was previously achieved by using electro-mechanical or analogue technology. Components and systems such as relay protection, rectifiers, inverters, variable speed drives and diesel-generator sets are today equipped with digital components. Several of the systems and components fulfil functions with a safety-role in the NPP. Recently, however, a number of incidents have occurred which highlight deficiencies in the design or HMI of the equipment, which warrants questions whether there are generic problems with some applications of digital components that needs to be addressed. The use of digital components has presented cost effective solutions, or even the only available solution on the market enabling a modernisation. The vast majority of systems using digital components have been operating without problems and often contribute to improved safety but the challenge of non-detectable, or non-identifiable, failure modes remain. In this paper, the extent to which digital components are used in Swedish NPP power systems will be presented including a description of typical applications. Based on data from maintenance records and fault reports, as well as interviews with designers and maintenance personnel, the main areas where problems have been encountered and where possible risks have been identified will be described. The paper intends to investigate any 'tell-tales' that could give signals of unwanted behaviour. Furthermore, particular benefits experienced by using digital components will be highlighted. The paper will also discuss the safety relevance of these findings and suggest measures to improve safety in the application of digital components in power systems. (authors)

  15. A Classification Method of Technical Security Controls for Digital I and C Systems in NPPs

    International Nuclear Information System (INIS)

    Song, J. G.; Lee, J. W.; Park, G. Y.; Kwon, K. C.; Lee, D. Y.; Lee, C. K.

    2012-01-01

    The instrumentation and control (I and C) systems in nuclear power plants (NPPs) are a key facility to monitor plant state, control plant devices, and prevent accidents. Recent I and C systems have been composed of digital systems in order to enhance the effectiveness of operation and maintenance of NPPs. An assessment method for the analysis of security controls is needed to respond to potential cyber attacks against digital I and C systems. RG 5.71 'Cyber Security Programs for Nuclear Facilities' published by U.S.NRC in 2010 presents a comprehensive set of security controls for NPPs. Although this document provides the requirements of security controls, a guidance describing which security controls should be applied to specific digital assets and how to implement them is still needed for the I and C system design and development. In this paper, a classification method of the technical security controls listed in RG 5.71 is proposed to provide a guide useful for the application of the controls during the design and implementation phases of I and C systems

  16. A Classification Method of Technical Security Controls for Digital I and C Systems in NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Song, J. G.; Lee, J. W.; Park, G. Y.; Kwon, K. C.; Lee, D. Y.; Lee, C. K. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    The instrumentation and control (I and C) systems in nuclear power plants (NPPs) are a key facility to monitor plant state, control plant devices, and prevent accidents. Recent I and C systems have been composed of digital systems in order to enhance the effectiveness of operation and maintenance of NPPs. An assessment method for the analysis of security controls is needed to respond to potential cyber attacks against digital I and C systems. RG 5.71 'Cyber Security Programs for Nuclear Facilities' published by U.S.NRC in 2010 presents a comprehensive set of security controls for NPPs. Although this document provides the requirements of security controls, a guidance describing which security controls should be applied to specific digital assets and how to implement them is still needed for the I and C system design and development. In this paper, a classification method of the technical security controls listed in RG 5.71 is proposed to provide a guide useful for the application of the controls during the design and implementation phases of I and C systems

  17. A user-friendly, digital console for the control room parameters supervision in old-generation nuclear plants

    International Nuclear Information System (INIS)

    Memmi, Fabrizio; Falconi, Luca; Cappelli, Mauro; Palomba, Mario; Sepielli, Massimo

    2016-01-01

    Highlights: • We propose a user-friendly monitoring system for reactor supervision. • Statistics from data analysis can be used to optimize reactor management. • The tool has been designed in order to include a simulation tool for prediction. • The proposed system could help operators in training and continuous learning. - Abstract: In this work a user-friendly, digital monitoring system for supervision of process variables coming from a fission nuclear reactor of TRIGA type (1-MW TRIGA reactor RC-1) is presented. The system, developed on the basis of COTS tools, can easily interface the control room instrumentation and display the typical monitoring parameters (e.g. nuclear power, temperatures, flow rates, radiological variables) in an intuitive, user-adjustable way for plant operators. A front panel of a virtual instrument allows for a direct measure while the acquisition system, for signals coming from the reactor, can process the data and generate a detailed representation of the results, whose statistics can be interpreted to optimize the reactor management parameters. This system has been also designed so as to include a simulation tool able to predict specific performances and investigate critical phenomena, and to optimize overall plant performances. In particular, it allows to have a feedback control and to perform several predictive statistical surveys of all main process parameters. The proposed system could help operators in training and continuous learning activities, and serve as a basis for an advanced decision support system and for a remote training tool for students and trainees not authorized to work in a radiation environment.

  18. A user-friendly, digital console for the control room parameters supervision in old-generation nuclear plants

    Energy Technology Data Exchange (ETDEWEB)

    Memmi, Fabrizio; Falconi, Luca; Cappelli, Mauro, E-mail: mauro.cappelli@enea.it; Palomba, Mario; Sepielli, Massimo

    2016-06-15

    Highlights: • We propose a user-friendly monitoring system for reactor supervision. • Statistics from data analysis can be used to optimize reactor management. • The tool has been designed in order to include a simulation tool for prediction. • The proposed system could help operators in training and continuous learning. - Abstract: In this work a user-friendly, digital monitoring system for supervision of process variables coming from a fission nuclear reactor of TRIGA type (1-MW TRIGA reactor RC-1) is presented. The system, developed on the basis of COTS tools, can easily interface the control room instrumentation and display the typical monitoring parameters (e.g. nuclear power, temperatures, flow rates, radiological variables) in an intuitive, user-adjustable way for plant operators. A front panel of a virtual instrument allows for a direct measure while the acquisition system, for signals coming from the reactor, can process the data and generate a detailed representation of the results, whose statistics can be interpreted to optimize the reactor management parameters. This system has been also designed so as to include a simulation tool able to predict specific performances and investigate critical phenomena, and to optimize overall plant performances. In particular, it allows to have a feedback control and to perform several predictive statistical surveys of all main process parameters. The proposed system could help operators in training and continuous learning activities, and serve as a basis for an advanced decision support system and for a remote training tool for students and trainees not authorized to work in a radiation environment.

  19. Design type testing for digital instrumentation and control systems

    International Nuclear Information System (INIS)

    Bastl, W.; Mohns, G.

    1997-01-01

    The design type qualification of digital safety instrumentation and control is outlined. Experience shows that the concepts discussed, derived from codes, guidelines and standards, achieve useful results. It has likewise become clear that the systematics of design type qualification of the hardware components is also applicable to the software components. Design type qualification of the software, a premiere, could be performed unexpectedly smoothly. The hardware design type qualification proved that the hardware as a substrate of functionality and reliability is an issue that demands full attention, as compared to conventional systems. Another insight is that design qualification of digital instrumentation and control systems must include plant-independent systems tests. Digital instrumentation and control systems simply work very differently from conventional control systems, so that this testing modality is inevitable. (Orig./CB) [de

  20. A dependability modeling of software under memory faults for digital system in nuclear power plants

    International Nuclear Information System (INIS)

    Choi, J. G.; Seong, P. H.

    1997-01-01

    In this work, an analytic approach to the dependability of software in the operational phase is suggested with special attention to the hardware fault effects on the software behavior : The hardware faults considered are memory faults and the dependability measure in question is the reliability. The model is based on the simple reliability theory and the graph theory which represents the software with graph composed of nodes and arcs. Through proper transformation, the graph can be reduced to a simple two-node graph and the software reliability is derived from this graph. Using this model, we predict the reliability of an application software in the digital system (ILS) in the nuclear power plant and show the sensitivity of the software reliability to the major physical parameters which affect the software failure in the normal operation phase. We also found that the effects of the hardware faults on the software failure should be considered for predicting the software dependability accurately in operation phase, especially for the software which is executed frequently. This modeling method is particularly attractive for the medium size programs such as the microprocessor-based nuclear safety logic program. (author)

  1. Management practice and innovation in digital I and C system maintenance of nuclear power plant

    International Nuclear Information System (INIS)

    Huang Qian; Shi Qingwei; Huang Yaning

    2012-01-01

    This essay introduces the application situation of new ideas and methods in aspects of risk analysis, equipment status monitoring, defect tracing and maintenance management network in the course of maintaining the digital I and C system of Tianwan Nuclear Power Station, gives a detail description about the enhancement of the enterprise culture and scientific innovation in the field of digital I and C system maintenance. The practices in the past several years show that the management practice and the innovation means in the field of digital I and C system maintenance of Tianwan Nuclear Power Station are effective, and can provide reference for the other projects in this regard. (authors)

  2. Digital Natives or Digital Tribes?

    Science.gov (United States)

    Watson, Ian Robert

    2013-01-01

    This research builds upon the discourse surrounding digital natives. A literature review into the digital native phenomena was undertaken and found that researchers are beginning to identify the digital native as not one cohesive group but of individuals influenced by other factors. Primary research by means of questionnaire survey of technologies…

  3. The reactor power control system based on digital control in nuclear power plant

    International Nuclear Information System (INIS)

    Liu Chong; Zhou Jianliang; Tan Ping

    2010-01-01

    The PLC (Programmable Logical Controller), digital communication and redundant techniques are applied in the rod control and position indication system(namely the reactor power control system) to perform the power control in the 300 MW reactor automatically and integrally in Qinshan Phase I project. This paper introduces the features, digital design methods of hardware of the instrumentation and control system (I and C) in the reactor power control. It is more convenient for the information exchange by human-machine interface (HMI), operation and maintenance, and the system reliability has been greatly improved after the project being reconstructed. (authors)

  4. Survey and analysis on environmental and electromagnetic effect on instrumentation and control equipment of nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, In Koo; Lee, Dong Young; Cha, Kyung Ho

    2001-03-01

    As the instrumentation and control (I and C) equipment suppliers tend to provide digital components rather than conventional analog type components for instrumentation and control systems of nuclear power plants(NPPs), it is unavoidable to adopt digital equipment for safety I and C systems as well as non-safety systems. However, the full introduction of digital equipment for I and C systems of nuclear power plants raises several concerns which have not been considered in conventional analog I and C equipment. The two major examples of the issues of digital systems are environmental/electromagnetic compatibility (EMC) and software reliability. This report presents the survey and research results on environmental and electromagnetic effect on I and C equipment of nuclear power plants to give a guideline for aging management and design process. Electromagnetic site surveys were conducted to be used as a part of technical basis to demonstrate that I and C systems are compatible with the ambient electromagnetic noise in Korean nuclear power plants.

  5. Digital platforms as enablers for digital transformation

    DEFF Research Database (Denmark)

    Hossain, Mokter; Lassen, Astrid Heidemann

    transformation is crucial. This study aims at exploring how organizations are driven towards transformation in various ways to embrace digital platforms for ideas, technologies, and knowledge. It shows the opportunities and challenges digital platforms bring in organizations. It also highlights underlying......Digital platforms offer new ways for organizations to collaborate with the external environment for ideas, technologies, and knowledge. They provide new possibilities and competence but they also bring new challenges for organizations. Understanding the role of these platforms in digital...... mechanisms and potential outcomes of various digital platforms. The contribution of the submission is valuable for scholars to understand and further explore this area. It provides insight for practitioners to capture value through digital platforms and accelerate the pace of organizations’ digital...

  6. The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

    International Nuclear Information System (INIS)

    O'Hara, J.M.; Gunther, W.; Martinez-Guridi, G.

    2010-01-01

    New and advanced reactors will use integrated digital instrumentation and control (I and C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I and C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I and C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I and C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I and C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it appear that a process disturbance has occurred. We used the information obtained as the technical basis upon which to develop HFE review guidance. The guidance addresses the treatment of degraded I and C conditions as part of the design process and the HSI features and functions that support operators to monitor I and C performance and manage I and C degradations when they occur. In addition, we identified topics for future research.

  7. Digital citizens Digital nations: the next agenda

    NARCIS (Netherlands)

    A.W. (Bert) Mulder; M.W. (Martijn) Hartog

    2015-01-01

    DIGITAL CITIZENS CREATE A DIGITAL NATION Citizens will play the lead role as they – in the next phase of the information society – collectively create a digital nation. Personal adoption of information and communication technology will create a digital infrastructure that supports individual and

  8. Probabilistic safety assessment for instrumentation and control systems in nuclear power plants: an overview

    International Nuclear Information System (INIS)

    Lu, Lixuan; Jiang, Jin

    2004-01-01

    Deregulation in the electricity market has resulted in a number of challenges in the nuclear power industry. Nuclear power plants must find innovative ways to remain competitive by reducing operating costs without jeopardizing safety. Instrumentation and Control (I and C) systems not only play important roles in plant operation, but also in reducing the cost of power generation while maintaining and/or enhancing safety. Therefore, it is extremely important that I and C systems are managed efficiently and economically. With the increasing use of digital technologies, new methods are needed to solve problems associated with various aspects of digital I and C systems. Probabilistic Safety Assessment (PSA) has proved to be an effective method for safety analysis and risk-based decisions, even though challenges are still present. This paper provides an overview of PSA applications in three areas of digital I and C systems in nuclear power plants. These areas are Graded Quality Assurance, Surveillance Testing, and Instrumentation and Control System Design. In addition, PSA application in the regulation of nuclear power plants that adopt digital I and C systems is also investigated. (author)

  9. Development of critical digital review procedure

    International Nuclear Information System (INIS)

    Huang Huiwen; Liao Benching; Tseng Maosheng; Chung Hsianghan; Cheng Tsungchieh; Chen Minghuei

    2011-01-01

    This paper describes the critical digital review (CDR) procedure, which was developed by Institute of Nuclear Energy Research (INER), and sponsored by Taiwan Power Company (TPC). A preliminary CDR application experience which was performed by INER, is also described in this paper. Currently, CDR becomes one of the policies for digital Instrumentation and Control (I and C) system replacement in TPC. The contents of this CDR procedure include: Scope, Responsibility, Operation Procedure, Operation Flow Chart, CDR review items. The 'CDR Review Items' chapter proposes optional review items, including the comparison of the design change, Software Verification and Validation (SV and V), Failure Mode and Effects Analysis (FMEA), Evaluation of Watchdog Timer, Evaluation of Electromagnetic Compatibility (EMC), Evaluation of Grounding for System/Component, Seismic Evaluation, HFE Evaluation, Witness and Inspection, Lessons Learnt from the Digital I and C Failure Events. Since CDR has become a TPC policy, Chin Shan Nuclear Power Plant (NPP) performed the CDR practice of Automatic Voltage Regulator (AVR) digital I and C replacement, even though the project had been on the half way. The major review items of this CDR were: the comparison of the design change, SV and V, FMEA, Evaluation of Watchdog Timer, Evaluation of Electromagnetic Compatibility (EMC), Evaluation of Grounding for System/ Component, Witness and Inspection, Lessons Learnt from the Digital I and C Failure Events. The experience of the CDR showed the importance of preparation of the documents by the vendor. This means the communication with the vendors for the bid preparation is crucial. (author)

  10. IGENPRO knowledge-based digital system for process transient diagnostics and management

    International Nuclear Information System (INIS)

    Morman, J.A.; Reifman, J.; Vitela, J.E.; Wei, T.Y.C.; Applequist, C.A.; Hippely, P.; Kuk, W.; Tsoukalas, L.H.

    1998-01-01

    Verification and validation issues have been perceived as important factors in the large scale deployment of knowledge-based digital systems for plant transient diagnostics and management. Research and development (R and D) is being performed on the IGENPRO package to resolve knowledge base issues. The IGENPRO approach is to structure the knowledge bases on generic thermal-hydraulic (T-H) first principles and not use the conventional event-basis structure. This allows for generic comprehensive knowledge, relatively small knowledge bases and above all the possibility of T-H system/plant independence. To demonstrate concept feasibility the knowledge structure has been implemented in the diagnostic module PRODIAG. Promising laboratory testing results have been obtained using data from the full scope Braidwood PWR operator training simulator. This knowledge structure is now being implemented in the transient management module PROMANA to treat unanticipated events and the PROTREN module is being developed to process actual plant data. Achievement of the IGENPRO R and D goals should contribute to the acceptance of knowledge-based digital systems for transient diagnostics and management. (author)

  11. IGENPRO knowledge-based digital system for process transient diagnostics and management

    International Nuclear Information System (INIS)

    Morman, J.A.; Reifman, J.; Wei, T.Y.C.

    1997-01-01

    Verification and validation issues have been perceived as important factors in the large scale deployment of knowledge-based digital systems for plant transient diagnostics and management. Research and development (R ampersand D) is being performed on the IGENPRO package to resolve knowledge base issues. The IGENPRO approach is to structure the knowledge bases on generic thermal-hydraulic (T-H) first principles and not use the conventional event-basis structure. This allows for generic comprehensive knowledge, relatively small knowledge bases and above all the possibility of T-H system/plant independence. To demonstrate concept feasibility the knowledge structure has been implemented in the diagnostic module PRODIAG. Promising laboratory testing results have been obtained using data from the full scope Braidwood PWR operator training simulator. This knowledge structure is now being implemented in the transient management module PROMANA to treat unanticipated events and the PROTREN module is being developed to process actual plant data. Achievement of the IGENPRO R ampersand D goals should contribute to the acceptance of knowledge-based digital systems for transient diagnostics and management

  12. Proceso de lixiviación carbonato-amociacal: control multivariable a través del arreglo inverso de Nyquist para el mezclado de mineral y licor

    Directory of Open Access Journals (Sweden)

    Roger Misa-Llorca

    2001-03-01

    Full Text Available El trabajo muestra el resultado obtenido por los autores en el estudio y simulación del sistema del Tanque de Contacto de mineral reducido con licor carbonato-amoniacal existente en la Industria del Níquel. Partiendo de un estudio de su comportamiento en lazo abierto, se seleccionan los tipos de controladores para ser implementados. Se elige primeramente una técnica de control clásica basada en el Controlador PID Multilazo y se compara con una técnica de control de avanzada, representada por el Controlador Multivariable con Desacoplamiento a partir del Arreglo Inverso de Nyquist. Los resultados finales son mostrados en gráficos y curvas de respuestas, simulados con MATLAB, lo que permite determinar el mejor desempeño.

  13. Application of Phase Shifting Projection Moire on Solid Regular Figures and Plant Organs Three Dimensional Digital Model Generation

    Science.gov (United States)

    Lino, A. C. L.; Dal Fabbro, I. M.

    2008-04-01

    The conception of a tridimensional digital model of solid figures and plant organs started from topographic survey of virtual surfaces [1], followed by topographic survey of solid figures [2], fruit surface survey [3] and finally the generation of a 3D digital model [4] as presented by [1]. In this research work, i.e. step number [4] tested objects included cylinders, cubes, spheres and fruits. A Ronchi grid named G1 was generated in a PC, from which other grids referred as G2, G3, and G4 were set out of phase by 1/4, 1/2 and 3/4 of period from G1. Grid G1 was then projected onto the samples surface. Projected grid was named Gd. The difference between Gd and G1 followed by filtration generated de moiré fringes M1 and so on, obtaining the fringes M2, M3 and M4 from Gd. Fringes are out of phase one from each other by 1/4 of period, which were processed by the Rising Sun Moiré software to produce packed phase and further on, the unpacked fringes. Tested object was placed on a goniometer and rotate to generate four surfaces topography. These four surveyed surfaces were assembled by means of a SCILAB software, obtaining a three column matrix, corresponding to the object coordinates xi, also having elevation values and coordinates corrected as well. The work includes conclusions on the reliability of the proposed method as well as the setup simplicity and of low cost.

  14. Seamless Digital Environment – Data Analytics Use Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-08-01

    Multiple research efforts in the U.S Department of Energy Light Water Reactor Sustainability (LWRS) Program studies the need and design of an underlying architecture to support the increased amount and use of data in the nuclear power plant. More specifically the three LWRS research efforts; Digital Architecture for an Automated Plant, Automated Work Packages, Computer-Based Procedures for Field Workers, and the Online Monitoring efforts all have identified the need for a digital architecture and more importantly the need for a Seamless Digital Environment (SDE). A SDE provides a mean to access multiple applications, gather the data points needed, conduct the analysis requested, and present the result to the user with minimal or no effort by the user. During the 2016 annual Nuclear Information Technology Strategic Leadership (NITSL) group meeting the nuclear utilities identified the need for research focused on data analytics. The effort was to develop and evaluate use cases for data mining and analytics for employing information from plant sensors and database for use in developing improved business analytics. The goal of the study is to research potential approaches to building an analytics solution for equipment reliability, on a small scale, focusing on either a single piece of equipment or a single system. The analytics solution will likely consist of a data integration layer, predictive and machine learning layer and the user interface layer that will display the output of the analysis in a straight forward, easy to consume manner. This report describes the use case study initiated by NITSL and conducted in a collaboration between Idaho National Laboratory, Arizona Public Service – Palo Verde Nuclear Generating Station, and NextAxiom Inc.

  15. Combating obsolescence - ACR digital control systems design

    International Nuclear Information System (INIS)

    Tikku, S.; Raiskums, G.

    2006-01-01

    The ever increasing use of digital technologies and products to meet the control, automation and monitoring needs of the nuclear power plant - even though justified by the benefits it provides - comes with an increased risk of technological obsolescence happening through the course of the plant life. Some well considered strategies are being employed in the ACR design process to minimise this risk and alleviate the consequence if it happens. These include application of a modular overall architecture, adoption of international widely accepted standards to harmonise equipment qualification and software practices, production of control functional specifications that are not influenced by target platform, and careful selection of technologies and products. (author)

  16. Integration of analog and digital instrumentation and control systems in hybrid control rooms

    International Nuclear Information System (INIS)

    2010-01-01

    he IAEA's activities in the area of nuclear power plant operating performance and life cycle management are aimed at increasing Member State capabilities in utilizing good engineering and management practices as developed and transferred by the IAEA. In particular, the IAEA supports the improvement of nuclear power plant performance, plant life management, training, power uprating, operational license renewal, and the modernization of instrumentation and control (I and C) systems of plants. The issue of the integration of analog and digital I and C systems in hybrid control rooms was suggested by the IAEA Technical Working Group on Nuclear Power Plant Control and Instrumentation (TWG-NPPCI) at its meetings in 2003 and 2005. The subject was then approved by the IAEA and included in its work programmes for 2006-2009. The purpose of this report is to help nuclear utilities in planning control room and other human system interface (HSI) changes, making appropriate use of modern technologies. These technologies would aid in managing ageing and obsolescence, and facilitate improvements in plant performance and safety. This report covers a broad spectrum of potential changes to the control room ranging from the replacement of a few obsolete components with newer digital devices to a fully computerized control room. New digital technologies offer significant opportunities to improve access to and presentation of information to the user, e.g. operators, maintenance staff and management. However, this technology should be used prudently. In some cases, modernization is undertaken to resolve ageing and obsolescence or to meet regulatory requirements for license renewal. The integration of new technologies during main control room (MCR) modernizations should be performed cautiously and all affected aspects of plant maintenance, and operation should be carefully considered, paying particular attention to the human factors elements of these aspects. This report describes a

  17. Human factors survey of advanced instrumentation and controls technologies in nuclear plants

    International Nuclear Information System (INIS)

    Carter, R.J.

    1992-01-01

    A survey of advanced instrumentation and controls (I ampersand C) technologies and associated human factors issues in the US and Canadian nuclear industries was carried out by a team from Oak Ridge national laboratory to provide background for the development of regulatory policy, criteria, and guides for review of advanced I ampersand C systems as well as human engineering guidelines for evaluating these systems. The survey found those components of the US nuclear industry surveyed to be quite interested in advanced I ampersand C, but very cautious in implementing such systems in nuclear facilities and power plants. The trend in the facilities surveyed is to experiment cautiously when there is an intuitive advantage or short-term payoff. In the control room, the usual practice is direct substitution of digital and microprocessor-based instruments or systems that are functionally identical to the analog instruments or systems being replaced. The most advanced I ampersand C systems were found in the Canadian CANDU plants, where the newest plant has digital system in almost 100% of its control systems and in over 70% of its plant protection system. The hypothesis that properly 'introducing digital systems increases safety' is supported by the Canadian experience. The performance of these digital systems was achieved using an appropriate quality assurance program for the software development. The ability of digital systems to detect impending failures and initiate a fail-safe action, is a significant safety issue that should be of special interest to every US utility as well as to the US Nuclear Regulatory Commission. (orig.)

  18. Old Plants, New Tricks: Phenological Research Using Herbarium Specimens.

    Science.gov (United States)

    Willis, Charles G; Ellwood, Elizabeth R; Primack, Richard B; Davis, Charles C; Pearson, Katelin D; Gallinat, Amanda S; Yost, Jenn M; Nelson, Gil; Mazer, Susan J; Rossington, Natalie L; Sparks, Tim H; Soltis, Pamela S

    2017-07-01

    The timing of phenological events, such as leaf-out and flowering, strongly influence plant success and their study is vital to understanding how plants will respond to climate change. Phenological research, however, is often limited by the temporal, geographic, or phylogenetic scope of available data. Hundreds of millions of plant specimens in herbaria worldwide offer a potential solution to this problem, especially as digitization efforts drastically improve access to collections. Herbarium specimens represent snapshots of phenological events and have been reliably used to characterize phenological responses to climate. We review the current state of herbarium-based phenological research, identify potential biases and limitations in the collection, digitization, and interpretation of specimen data, and discuss future opportunities for phenological investigations using herbarium specimens. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Development of Risk Assessment Technology for Low Power, Shutdown and Digital I and C System

    International Nuclear Information System (INIS)

    Jang, Seung Cheol; Kang, Hyun Gook; Lim, Ho Gon; Park, Jin Hee; Kang, Dae Il; Eom, Heung Sub; Kim, Man Cheol; Lee, Ho Joong; Kim, Jae Whan; Ha, Jae Joo

    2007-06-01

    There are two technical areas to deal with in the project: the low power and shutdown probabilistic safety assessment (PSA), and the digital I and C PSA. The scope and contents of each area could be summarized as follows: The LPSD PSA Area Ο Quality improvement of the KSNP LPSD PSA model in the following four technical areas; human reliability analysis (HR), system analysis (SY), data analysis (DA) and accident sequence quantification (QU) Ο Development of the LPSD configuration risk management(CRM) model - Study on the methodology for developing a CRM model, so-called ASLOC (Autonomous Shutdown LOgic Creation) - Development of the LPSD CRM model for the units of Ulchin 3 and 4 The Digital I and C PSA Area Ο Development of impact model of ESF-CCS on plant risks - Unavailability analysis of ESF-CCS for APR-1400 - Digital plant risk models for evaluating core damage frequency (CDF) Ο Study on the methodologies for treating digital-specific problems in the digital I and C PSA - Study on the methodology for evaluating safety-critical SW reliability by BBN techniques, including a feasibility study of reliability growth model - Study on the methodology for the safety-critical network system by Markov chain

  20. The research for the design verification of nuclear power plant based on VR dynamic plant

    International Nuclear Information System (INIS)

    Wang Yong; Yu Xiao

    2015-01-01

    This paper studies a new method of design verification through the VR plant, in order to perform verification and validation the design of plant conform to the requirements of accident emergency. The VR dynamic plant is established by 3D design model and digital maps that composed of GIS system and indoor maps, and driven by the analyze data of design analyzer. The VR plant could present the operation conditions and accident conditions of power plant. This paper simulates the execution of accident procedures, the development of accidents, the evacuation planning of people and so on, based on VR dynamic plant, and ensure that the plant design will not cause bad effect. Besides design verification, simulated result also can be used for optimization of the accident emergency plan, the training of accident plan and emergency accident treatment. (author)

  1. Long-term preventive maintenance of instrumentation control equipment for PWR plants

    International Nuclear Information System (INIS)

    Sugitani, S.; Nanba, M.

    2006-01-01

    Since the PWR plants in Japan have been operated more than 30 years, main instrumentation control equipment of analog systems has been renewed to digital control systems. Renewal works had to be done in short period within periodical inspection term and for several facilities. The Mitsubishi LTD group had been provided with these market needs by its digital control system (MELTAC-NplusR 3) applicable to main instrumentation control equipment for primary and secondary systems and had already finished the renewal for practical plants. (T. Tanaka)

  2. Light Water Reactor Sustainability Program: Digital Architecture Project Plan

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Ken [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    There are many technologies available to the nuclear power industry to improve efficiency in plant work activities. These range from new control room technologies to those for mobile field workers. They can make a positive impact on a wide range of performance objectives – increase in productivity, human error reduction, validation of results, accurate transfer of data, and elimination of repetitive tasks. It is expected that the industry will more and more turn to these technologies to achieve these operational efficiencies to lower costs. At the same time, this will help utilities manage a looming staffing problem as the inevitable retirement wave of the more seasoned workers affects both staffing levels and knowledge retention. A barrier to this wide-scale implementation of new technologies for operational efficiency is the lack of a comprehensive digital architecture that can support the real-time information exchanges needed to achieve the desired operational efficiencies. This project will define an advanced digital architecture that will accommodate the entire range of system, process, and plant worker activity to enable the highest degree of integration, thereby creating maximum efficiency and productivity. This pilot project will consider a range of open standards that are suitable for the various data and communication requirements of a seamless digital environment. It will map these standards into an overall architecture to support the II&C developments of this research program.

  3. Dismantling and waste managing benefit from digital technologies

    International Nuclear Information System (INIS)

    Moitrier, C.

    2017-01-01

    Dismantling is a very important challenge for nuclear industry as its success will prove the ability of the industry to deal with all the stages of a nuclear power plant from design to the end. A dismantling project is constraint by costs, time, feasibility, safety and environment protection and all of this implies a perfect knowledge of both the initial state of the facility at the beginning of the dismantling and the supply chain to avoid delays and extra-costs. Digital tools have a very important role to play as a provider of a 3-dimensional digital twin of the facility. This digital model allows: a remote preparation of the dismantling actions, to assess and optimize the radiation exposure during the intervention, to simulate various scenarios and select the most adequate, to ease collaborative work between various teams, to assess the volume and kind of waste at a very early stage of the dismantling, and to train operators and workers for x. (A.C.)

  4. New technology for BWR power plant control and instrumentation

    International Nuclear Information System (INIS)

    Takano, Yoshiyuki; Nakamura, Makoto; Murata, Fumio.

    1992-01-01

    Nuclear power plants are facing strong demands for higher reliability and cost-performance in their control and instrumentation systems. To meet these needs, Hitachi is developing advanced control and instrumentation technology by rationalizing the conventional technology in that field. The rationalization is done through the utilization of reliable digital technology and optical transmission technology, and others, which are now commonly used in computer applications. The goal of the development work is to ensure safe, stable operation of the plant facilities and to secure harmony between man and machine. To alleviate the burdens of the operators, the latest electronic devices are being employed to create an advanced man-machine interface, and to promote automatic operation of the plant based upon the automatic operation of individual systems. In addition, the control and instrumentation system, including the safety system, incorporates more and more digital components in order to further enhance the reliability and maintainability of the plant. (author)

  5. Reliability analysis of digital I and C systems at KAERI

    International Nuclear Information System (INIS)

    Kim, Man Cheol

    2013-01-01

    This paper provides an overview of the ongoing research activities on a reliability analysis of digital instrumentation and control (I and C) systems of nuclear power plants (NPPs) performed by the Korea Atomic Energy Research Institute (KAERI). The research activities include the development of a new safety-critical software reliability analysis method by integrating the advantages of existing software reliability analysis methods, a fault coverage estimation method based on fault injection experiments, and a new human reliability analysis method for computer-based main control rooms (MCRs) based on human performance data from the APR-1400 full-scope simulator. The research results are expected to be used to address various issues such as the licensing issues related to digital I and C probabilistic safety assessment (PSA) for advanced digital-based NPPs. (author)

  6. Technical self reliance of digital safety systems

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Kee Choon; Lee, Dong Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Kook Hun [Doosan Heavy Industries and Construction, Changwon (Korea, Republic of); Choi, Seung Gap [POSCON, Pohang (Korea, Republic of)

    2009-04-15

    This paper summarizes the development results of the Korea Nuclear Instrumentation and Control System (KNICS) project sponsored by the Korean government. In this project, Man Machine Interface System (MMIS) architecture, two digital platforms, and several control systems are developed. One platform is a programmable Logic Controller (PLC) for a safety system and another platform is a Distributed Control System (DCS) for a non safety system. With the POSAFE Q PLC, a Reactor Protection System (RPS) and an Engineered Safety Feature Component Control System (ESF CCS) are developed. A Power Control System (PCS) is developed based on the DCS. The safety grade platform and the digital safety systems obtained approval for the Topical Report from the Korean regulatory body in February of 2009. Also a Korean utility and a vendor company determined KNICS results to apply them to the planned Nuclear Power Plant (NPP) in March 2009. This paper introduces the technical self reliance experiences of the safety grade platform and the digital safety systems developed in the KNICS R and D project.

  7. Increasing the efficiency of digitization workflows for herbarium specimens.

    Science.gov (United States)

    Tulig, Melissa; Tarnowsky, Nicole; Bevans, Michael; Anthony Kirchgessner; Thiers, Barbara M

    2012-01-01

    The New York Botanical Garden Herbarium has been databasing and imaging its estimated 7.3 million plant specimens for the past 17 years. Due to the size of the collection, we have been selectively digitizing fundable subsets of specimens, making successive passes through the herbarium with each new grant. With this strategy, the average rate for databasing complete records has been 10 specimens per hour. With 1.3 million specimens databased, this effort has taken about 130,000 hours of staff time. At this rate, to complete the herbarium and digitize the remaining 6 million specimens, another 600,000 hours would be needed. Given the current biodiversity and economic crises, there is neither the time nor money to complete the collection at this rate.Through a combination of grants over the last few years, The New York Botanical Garden has been testing new protocols and tactics for increasing the rate of digitization through combinations of data collaboration, field book digitization, partial data entry and imaging, and optical character recognition (OCR) of specimen images. With the launch of the National Science Foundation's new Advancing Digitization of Biological Collections program, we hope to move forward with larger, more efficient digitization projects, capturing data from larger portions of the herbarium at a fraction of the cost and time.

  8. Digital forensics digital evidence in criminal investigations

    CERN Document Server

    Marshall, Angus McKenzie

    2009-01-01

    The vast majority of modern criminal investigations involve some element of digital evidence, from mobile phones, computers, CCTV and other devices. Digital Forensics: Digital Evidence in Criminal Investigations provides the reader with a better understanding of how digital evidence complements "traditional" scientific evidence and examines how it can be used more effectively and efficiently in a range of investigations. Taking a new approach to the topic, this book presents digital evidence as an adjunct to other types of evidence and discusses how it can be deployed effectively in s

  9. Proposta metodológica para avaliação de controlador automático de seções e pulverização Proposed methodology for evaluation of automatic controller of boom sections and spray

    Directory of Open Access Journals (Sweden)

    Étore F Reynaldo

    2011-02-01

    Full Text Available Na aplicação de produtos fitossanitários, a utilização de equipamentos que controlam automaticamente as seções da barra e a pulverização já é realidade; entretanto, ainda não há resultados que demonstrem a sua eficácia. Por esse motivo, este trabalho teve por finalidade desenvolver uma metodologia para a avaliação de um equipamento que controla automaticamente as seções e a pulverização. Avaliou-se um controlador automático de seções e pulverização de mercado, e, para tanto, foram utilizados três níveis de acurácia do sinal de GPS (algoritmo interno, SBAS e RTK, três ângulos para a simulação de entrada e saída da barra de pulverização em relação à borda do talhão (0; 45 e 60º e três velocidades de trabalho (1,66; 5,00 e 8,33 m s-1. A metodologia proposta possibilitou a determinação dos tempos e distâncias de abertura e fechamento das seções. Os coeficientes de variação para os tempos e distâncias de abertura e fechamento das seções indicaram uma variação considerável. Houve interações significativas em função do tipo de sinal de GPS. A configuração recomendada pelo fabricante e adotada para a avaliação do controlador automático de seções e pulverização não atende a todas as situações simuladas.In the application of pesticides, the use of equipment that automatically controls the sections of the boom and the spray is already reality. However, there are no results to show its effectiveness. Therefore, this work was to develop a methodology for the evaluation of equipments which automatically controls the boom sections and the spraying pattern. A commercial automatic controller of boom spraying sections was evaluated using three levels of GPS accuracy (internal algorithm, SBAS and RTK, three angles for the simulation of entry and exit of the spray bar on field edges (0, 45 and 60 º and three forward speeds (1.66, 5.00 and 8.33 m s-1. The proposed methodology allowed the

  10. Pengembangan Sistem Proteksi Digital Arus Lebih Berbasis Logika Fuzzy sebagai Pengaman PLTMH

    Directory of Open Access Journals (Sweden)

    Cahayahati

    2013-09-01

    Full Text Available In this paper discussed digital overcurrent protection system fuzzy logic on plant systems or Micro Hydro Power Plants with fuzzy logic approach to the identification of the signal changes due to interference overcurrent short circuit the lifeboat station on the system. A digital overcurrent protection with a fuzzy logic-based method and the rules set if-then, fuzzification and defazzification which has 2 inputs are crisp and delta error and error the actual fault current has a crisp output 1 to input changes in current to drive the relay breaker. This system consists of a hardware system with microcontroller (mc ATMega8535 and other series as well as software that helps in the protection process performance Delpi 7 computer using fuzzy logic and program using C language and dicompel with CodeVisionAVR software and uploaded to the microcontroller using ponyprog2000 ATMega8535. The success of a prototype digital overcurrent protection system was tested on a fuzzy logic system voltage of 220 volts with a simple system technique burdened beyond any current settings and calculated over a given working time protection relay. After testing and calculations, then the inverse Characteristics of digital protection between the current disruption to the working time protection can be envisaged that a larger fault current less time working to secure protection from interference generating systems.

  11. Development of NPTC-11 intelligence control instrument with digital display

    International Nuclear Information System (INIS)

    Wang Chengming; Pu Li; Yu Jiang; Xue Yuping; Zhang Bo; Chen Yong

    2007-01-01

    The accurate of the process control gauge has direct influence on the safe operation of nuclear power plants. Therefore it is necessary to accumulate experiences for the domestic development of this Instrument. In this paper, NPTC-11 intelligence control Instrument with digital display is developed based on the design code for nuclear Instrument, considering the actual application requirements and technical redundancy. Its application in nuclear power plant for almost one year indicates that this Instrument satisfies the development purpose and requirements. (authors)

  12. Digital radiology and digitally formatted image management systems

    International Nuclear Information System (INIS)

    Cox, G.G.; Dwyer, S.J. III; Templeton, A.W.

    1987-01-01

    The number of diagnostic examinations performed with digitally formatted imaging equipment is increasing. Digital general-purpose and fluoroscopic radiology systems are being clinically evaluated. Digitizing conventional x-ray films, such as mammograms, frequently improves the diagnostic quality of the images. The digitizing process with laser has also afforded the opportunity to document required spatial resolution for digital imaging and network systems. The use of digitally formatted image instrumentation imposes new requirements on the acquisition, display and manipulation, transmission, hard copy image recording, and archiving of diagnostic data. Networking of digitally formatted image data offers many advantages for managing digital information. This paper identifies and describes digital radiographic systems. Parameters required for designing and implementing a digital image management system are outlined. Spatial and contrast resolution requirements are identified. The key parameters include the amount of image data generated each working day, the retrieval rate of the generated data, the display hardware and software needed for interactive diagnosis display stations, the requirements for analog hard copy generation, and on-line and long-term archiving requirements. These image management systems are often called PACS (Picture Archiving and Communication Systems)

  13. Control Robusto de Orden Fraccionario de la Presión del Vapor en el Domo Superior de una Caldera Bagacera

    Directory of Open Access Journals (Sweden)

    R. Rivas-Perez

    2014-01-01

    Full Text Available Resumen: En el presente trabajo se desarrolla un controlador de orden fraccionario del tipo IDα-1 para el control robusto de la presión de vapor en el domo superior de una caldera bagacera, el cual posibilita aumentar la efectividad en el control, así como la eficiencia energética de estos equipos. La aplicación de un controlador de orden fraccionario se justifica por el hecho de que la dinámica del proceso objeto de estudio puede cambiar de forma drástica con la variación del calor especifico de combustión (I. Se obtiene un modelo matemático nominal de la variación de la presión de vapor en el domo superior de la caldera bagacera. Los resultados de validación del modelo matemático obtenido muestran un elevado grado de adecuación. Mediante estudios experimentales se estimó el rango de variación de los parámetros dinámicos del modelo matemático obtenido cuando el calor específico de combustión varía en el rango de operación [Imin,-1Imax]. El diseño del controlador IDα se realiza en base a especificaciones en el dominio de la frecuencia. Se muestran los resultados comparativos de simulación del sistema de control desarrollado con controladores IDα-1 vs PI e IDα-1 vs PID, en el sentido de exhibir el mismo comportamiento dinámico en lazo cerrado para las especificaciones de la planta nominal y en presencia de perturbaciones. Estos resultados demuestran que cuando la ganancia de la presión del vapor en el domo superior de la caldera bagacera presenta variaciones en-1el rango [Kmin, Kmax] el controlador IDα diseñado exhibe mejores prestaciones, así como una mayor robustez. Abstract: This paper presents a fractional order controller of the class IDα-1 for robust control of the steam pressure in the steam drum of a bagasse boiler. The proposed controller improves the effectiveness on the control, and likewise the energy efficiency of this plant. The

  14. Quantitative evaluation of fault coverage for digitalized systems in NPPs using simulated fault injection method

    International Nuclear Information System (INIS)

    Kim, Suk Joon

    2004-02-01

    Even though digital systems have numerous advantages such as precise processing of data, enhanced calculation capability over the conventional analog systems, there is a strong restriction on the application of digital systems to the safety systems in nuclear power plants (NPPs). This is because we do not fully understand the reliability of digital systems, and therefore we cannot guarantee the safety of digital systems. But, as the need for introduction of digital systems to safety systems in NPPs increasing, the need for the quantitative analysis on the safety of digital systems is also increasing. NPPs, which are quite conservative in terms of safety, require proving the reliability of digital systems when applied them to the NPPs. Moreover, digital systems which are applied to the NPPs are required to increase the overall safety of NPPs. however, it is very difficult to evaluate the reliability of digital systems because they include the complex fault processing mechanisms at various levels of the systems. Software is another obstacle in reliability assessment of the systems that requires ultra-high reliability. In this work, the fault detection coverage for the digital system is evaluated using simulated fault injection method. The target system is the Local Coincidence Logic (LCL) processor in Digital Plant Protection System (DPPS). However, as the LCL processor is difficult to design equally for evaluating the fault detection coverage, the LCL system has to be simplified. The simulations for evaluating the fault detection coverage of components are performed by dividing into two cases and the failure rates of components are evaluated using MIL-HDBK-217F. Using these results, the fault detection coverage of simplified LCL system is evaluated. In the experiments, heartbeat signals were just emitted at regular interval after executing logic without self-checking algorithm. When faults are injected into the simplified system, fault occurrence can be detected by

  15. Development of basic technology for instrumentation and control - Development of digital automatic supervisory limitation system and its design= validation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung In; Chung, Sung Wook; Koh, Won Seok [Kyungwon University, Sungman (Korea, Republic of); Suh, Duk Young; Cheon, Sei Young [Kyunghee University, Seoul (Korea, Republic of); Lee, Sang Kyung; Kim, Sung Hun [Seoul National University, Seoul (Korea, Republic of)

    1995-07-01

    A major objective of the project is to develop a digital automatic supervisory limitation system and validate its design for the next generation= nuclear power plant. The limitation system assures that the plant does not exceed the operating limits by regulation the plant operations through on-line monitoring the operating margins of the critical parameters. A new conceptual model of power maneuverability has been proposed for the design of the limitation system and for its validation. Also, the limitation system monitors overall operation processes throughout a nuclear power plant by implementing hierarchical communication networks. Based on the conceptual design in software of the 1 st year results, the detailed design of the limitation system has been performed during the 2 nd year with constructing a prototype digital system. The system consists of the software module for plant simulation and the hardware module for implementation of limitation system and the associated interfaces in hardware. The limitation algorithm were implemented into the microprocessor and the interfaces were realized through the I/O modules. Also, these modules are incorporated into the communication networks. The products of the project could be directly applicable to the following nuclear unit adopting the limitation system, providing the bumpless transition to the commercial design phase. And the prototype evaluation scheme will be very useful for the succeeding studies related to the digital nuclear I and C fields, such as fault-tolerance design methods, software verification and validation and response time execution of digital systems. 69 refs., 3 tabs., 44 figs. (author)

  16. Multi-scale entropy analysis of VR-based analog-digital system of the operator mental workload

    International Nuclear Information System (INIS)

    Lee Chunyi; Hung Tamin; Sun Tienlung; Yang Chihwei; Cheng Tsungchieh; Yang Lichen

    2011-01-01

    In the past, serious accidents of nuclear power plant usually had relation with the negligence, error handling and wrong decisions of operators. Therefore, to understand and be able to measure mental workload levels of operators are significant for safety issues in the nuclear power plant, especially when operators face emergency conditions. Therefore, this study is to determine the physiological indicators to measure the operator in the task of mental workload. This paper was to use electrocardiogram (ECG) measurements, to collect the RR-Interval data; heart rate variability (HRV) to analysis the complexity of the operator. After importing the data to calculate heart rate variability of complexity analysis, it can help us to understand the operator for the analog-digital platform adaptation. The virtual analog-digital nuclear plant control room is built using a 3D game development tool called Unity3D. (author)

  17. Development of network communication function for digitalized neutron flux monitoring instrument

    International Nuclear Information System (INIS)

    Li Kai; Zhang Liangju; Chen Xiaojun; Li Baoxiang

    2002-01-01

    It is essential for a digitalized Neutron Flux Monitoring Instrument to communicate with other parts of Instrumentation and Control System in a network environment, and it is fairly different from the case of traditional analogue nuclear instrumentation. How to satisfy all the requirements of different network structure and communication protocol, which might be adopted in different target nuclear power plant, is a key issue in the design and development of a digitalized neutron flux monitoring instrument. The author describes the overall communication scheme, mainly discusses the design idea and the requirements of the communication interfaces and the implementation of the RS-485 interface as an example of the digitalized neutron flux monitoring instrument, which is under development in the institute

  18. Software Safety Analysis of Digital Protection System Requirements Using a Qualitative Formal Method

    International Nuclear Information System (INIS)

    Lee, Jang-Soo; Kwon, Kee-Choon; Cha, Sung-Deok

    2004-01-01

    The safety analysis of requirements is a key problem area in the development of software for the digital protection systems of a nuclear power plant. When specifying requirements for software of the digital protection systems and conducting safety analysis, engineers find that requirements are often known only in qualitative terms and that existing fault-tree analysis techniques provide little guidance on formulating and evaluating potential failure modes. A framework for the requirements engineering process is proposed that consists of a qualitative method for requirements specification, called the qualitative formal method (QFM), and a safety analysis method for the requirements based on causality information, called the causal requirements safety analysis (CRSA). CRSA is a technique that qualitatively evaluates causal relationships between software faults and physical hazards. This technique, extending the qualitative formal method process and utilizing information captured in the state trajectory, provides specific guidelines on how to identify failure modes and the relationship among them. The QFM and CRSA processes are described using shutdown system 2 of the Wolsong nuclear power plants as the digital protection system example

  19. Completely contained and remotely operated digital density meter

    International Nuclear Information System (INIS)

    Goergen, C.R.

    1979-10-01

    A completely contained and remotely operated density determination system having unique features was designed, fabricated, and installed at the Savannah River Plant. The system, based on a Mettler calculating digital density meter, provides more precise and accurate results than the falling drop technique for measuring densities. The system is fast, simple, easy to operate, and has demonstrated both reliability and durability

  20. Example Plant Model for an International Benchmark Study on DI and C PSA

    International Nuclear Information System (INIS)

    Shin, Sung Min; Park, Jinkyun; Jang, Wondea; Kang, Hyun Gook

    2016-01-01

    In this context the risk quantification due to these digitalized safety systems became more important. Although there are many challenges to address about this issue, many countries agreed with the necessity of research on reliability quantification of DI and C system. Based on the agreement of several countries, one of internal research association is planning a benchmark study on this issue by sharing an example digitalized plant model and let each participating member develop its own probabilistic safety assessment (PSA) model of digital I and C systems. Although the DI and C systems are being applied to NPPs, of which modeling method to quantify its reliability still ambiguous. Therefore, an internal research association is planning a benchmark study to address this issue by sharing an example digitalized plant model and let each member develop their own PSA model for DI and C systems

  1. Integrated dataset of anatomical, morphological, and architectural traits for plant species in Madagascar

    Directory of Open Access Journals (Sweden)

    Amira Azizan

    2017-12-01

    Full Text Available In this work, we present a dataset, which provides information on the structural diversity of some endemic tropical species in Madagascar. The data were from CIRAD xylotheque (since 1937, and were also collected during various fieldworks (since 1964. The field notes and photographs were provided by French botanists; particularly by Francis Hallé. The dataset covers 250 plant species with anatomical, morphological, and architectural traits indexed from digitized wood slides and fieldwork documents. The digitized wood slides were constituted by the transverse, tangential, and radial sections with three optical magnifications. The main specific anatomical traits can be found within the digitized area. Information on morphological and architectural traits were indexed from digitized field drawings including notes and photographs. The data are hosted in the website ArchiWood (http://archiwood.cirad.fr. Keywords: Morpho-architectural traits, Plant architecture, Wood anatomy, Madagascar

  2. Review and evaluation of technology, equipment, codes and standards for digitization of industrial radiographic film

    International Nuclear Information System (INIS)

    1992-05-01

    This reports contains a review and evaluation of the technology, equipment, and codes and standards related to the digitization of industrial radiographic film. The report presents recommendations and equipment-performance specifications that will allow the digitization of radiographic film from nuclear power plant components in order to produce faithful reproductions of flaw images of interest on the films. Justification for the specifications selected are provided. Performance demonstration tests for the digitization process are required and criteria for such tests is presented. Also several comments related to implementation of the technology are presented and discussed

  3. Digital citizenship and neoliberalization: governing digital citizens in Denmark

    DEFF Research Database (Denmark)

    Schou, Jannick; Hjelholt, Morten

    2018-01-01

    Digital citizenship is becoming increasingly normalized within advanced democratic states. As society and governmental institutions become reliant on digital technologies, citizens are expected to be and act digitally. This article examines the governance of digital citizens through a case study...... this case study, the article contributes to current critical perspectives on the digital citizen as a new political figure. It adds new insights into digital citizenship by connecting this figure to wider processes of neoliberalization and state restructuring, pushing for a more pronounced focus...... of digitalization efforts in Denmark. Drawing on multiple forms of data, the article showcases how digital citizens are governed through a combination of discursive, legal and institutional means. The article highlights the political, but also institutional work that goes into making citizens digital. Providing...

  4. Digital radiography

    International Nuclear Information System (INIS)

    Brody, W.R.

    1984-01-01

    Digital Radiography begins with an orderly introduction to the fundamental concepts of digital imaging. The entire X-ray digital imagining system is described, from an overall characterization of image quality to specific components required for a digital radiographic system. Because subtraction is central to digital radiographic systems, the author details the use of various subtraction methods for image enhancement. Complex concepts are illustrated with numerous examples and presented in terms that can readily be understood by physicians without an advanced mathematics background. The second part of the book discusses implementations and applications of digital imagining systems based on area and scanned detector technologies. This section includes thorough coverage of digital fluoroscopy, scanned projection radiography, and film-based digital imaging systems, and features a state-of-the-art synopsis of the applications of digital subtraction angiography. The book concludes with a timely assessment of anticipated technological advances

  5. Engineered safeguards systems and method in nuclear power plant training simulator

    International Nuclear Information System (INIS)

    Desalu, A.A.

    1977-01-01

    A method and system is disclosed for simulating the dynamic realtime operation of a nuclear power plant wherein a plurality of remote control devices provide input data to a digital computer to calculate physical values corresponding to plant operation to operate indicating devices for monitoring the physical operation of the plant. 24 claims, 29 figures

  6. Fieldbus: technology application in a 60Co sterilization plant

    International Nuclear Information System (INIS)

    Karam, D.; Sampa, M.H.O.; Rela, P.R.

    2000-01-01

    Process instrumentation was made by pressure signals in the 1940s. In the 1960s, 4-20 mA analogue signals were introduced. The development of digital processors in the 1970s sparked the use of computers to monitor and control instruments from a central point. In the 1980s smart sensors were developed and implemented in digital control, microprocessor environments. Fieldbus is a generic-term that describes a new digital communications network. The network is a digital, bi-directional, multidrop, serial-bus, and communications network used to link isolated field devices, such as controllers, transducers, actuators and sensors. Fieldbus technology may improve quality, reduce costs and increase efficiency because information is transmitted digitally without analog to digital or digital to analog converters, which also minimizes hardware errors. Fieldbus communication is based on two-wire communication, interconnecting all the components in the system. This paper introduces Fieldbus technology in a 60 Co sterilization plant

  7. Identificación y control de un Vehículo Aéreo no Tripulado tipo Quadcopter

    Directory of Open Access Journals (Sweden)

    Eduardo Giraldo Suarez

    2016-07-01

    Full Text Available En este artículo se aplica el algoritmo de identificación por mínimos cuadrados a un vehículo aéreo no tripulado tipo QuadCopter. El modelo se linealiza alrededor de un punto de operación y posteriormente se aplican controladores por realimentación de estados y LQR; este último demostró superioridad ante un controlador PID convencional.

  8. Harnessing Biomedical Natural Language Processing Tools to Identify Medicinal Plant Knowledge from Historical Texts.

    Science.gov (United States)

    Sharma, Vivekanand; Law, Wayne; Balick, Michael J; Sarkar, Indra Neil

    2017-01-01

    The growing amount of data describing historical medicinal uses of plants from digitization efforts provides the opportunity to develop systematic approaches for identifying potential plant-based therapies. However, the task of cataloguing plant use information from natural language text is a challenging task for ethnobotanists. To date, there have been only limited adoption of informatics approaches used for supporting the identification of ethnobotanical information associated with medicinal uses. This study explored the feasibility of using biomedical terminologies and natural language processing approaches for extracting relevant plant-associated therapeutic use information from historical biodiversity literature collection available from the Biodiversity Heritage Library. The results from this preliminary study suggest that there is potential utility of informatics methods to identify medicinal plant knowledge from digitized resources as well as highlight opportunities for improvement.

  9. Transmission and distribution of information in power plants

    International Nuclear Information System (INIS)

    Pinkernell, H.

    1978-01-01

    Operation of modern large-site power plants is no longer imaginable without facilities for automatic control. Brown-Boveri Company has developed a promising control system for power plants called Procontrol k. An essential piece of the system is DATRAS k, a digital bus-oriented data transport system for transmitting and distributing signals in power plants. DATRAS will save a large amount of cables and reduce the constructional effect. It offers opportunities for diagnosis and service and by means of continuous monitoring of all system components it will essentially improve plant availability. (orig.) [de

  10. Digitization

    DEFF Research Database (Denmark)

    Finnemann, Niels Ole

    2014-01-01

    what a concept of digital media might add to the understanding of processes of mediatization and what the concept of mediatization might add to the understanding of digital media. It is argued that digital media open an array of new trajectories in human communication, trajectories which were...

  11. The New Digital Divide For Digital BioMarkers.

    Science.gov (United States)

    Torous, John; Rodriguez, Jorge; Powell, Adam

    2017-09-01

    As smartphone and sensors continue to become more ubiquitous across the world, digital biomarkers have emerged as a scalable and practical tool to explore disease states and advance health. But as the digital divide of access and ownership begins to fade, a new digital divide is emerging. Who are the types of people that own smartphones or smart watches, who are the types of people that download health apps or partake in digital biomarker studies, and who are the types of people that are actually active with digital biomarkers apps and sensors - the people providing the high quality and longitudinal data that this field is being founded upon? Understanding the people behind digital biomarkers, the very people this emerging field aims to help, may actually be the real challenge as well as opportunity for digital biomarkers.

  12. Advanced digital PWR plant protection system based on optimal estimation theory

    International Nuclear Information System (INIS)

    Tylee, J.L.

    1981-04-01

    An advanced plant protection system for the Loss-of-Fluid Test (LOFT) reactor plant is described and evaluated. The system, based on a Kalman filter estimator, is capable of providing on-line estimates of such critical variables as fuel and cladding temperature, departure from nucleate boiling ratio, and maximum linear heat generation rate. The Kalman filter equations are presented, as is a description of the LOFT plant dynamic model inherent in the filter. Simulation results demonstrate the performance of the advanced system

  13. Estimativa da área foliar de meloeiro em estádios fenológicos por fotos digitais Estimate of the leaf area of melon plant in growing stages for digital photos

    Directory of Open Access Journals (Sweden)

    Sidinei José Lopes

    2007-08-01

    Full Text Available O objetivo deste trabalho foi avaliar a precisão do método de fotos digitais na estimativa da área foliar de meloeiro e encontrar modelos matemáticos de estimativa da área foliar em função de medidas lineares da folha para diferentes estádios fenológicos. Foram fotografadas todas as folhas ímpares de 8 plantas após transplante definitivo, através de câmera fotográfica digital, resultando, durante todo o ciclo da cultura, em 4.188 fotos, das quais mediu-se a área foliar, o comprimento e a largura da folha, por meio do software Sigma Scan Pro v. 5.0, Jandel Scientific. Para verificar a precisão do método de fotos digitais, retirou-se uma amostra de 40 folhas, de onde foram obtidas a área foliar através do método padrão de discos foliares e pelo método de fotos. Foi encontrada uma correlação de 0,99 entre o método padrão (discos e o de fotos. O método de fotos digitais pode ser utilizado para estimar a área foliar da cultura de meloeiro, e a estimativa da área foliar de meloeiro por estádio fenológico apresenta maior precisão, sendo a maior variabilidade na estimativa da área da folha observada no período reprodutivo. A largura máxima da folha de meloeiro é a medida linear que melhor estima a área foliar.This experiment was aimed at evaluating the precision of digital photos in estimating the leaf area of watermelon plants and to find mathematical models that estimates leaf area as a function of leaf linear measurements at different growth stages. All odd leaves of eight plants were photographed after being established on the field using a digital camera that resulted in 4,188 photos in which length and width were measured using a Sigma Scan Pro v. 5.0 Jandel Scientific software. In order to estimate the precision of the digital photos method, a sample consisting of 40 leaves was taken and leaf area measured using the standard leaf disks and the photo method. A 0.99 correlation coefficient was detected between

  14. Digitization errors using digital charge division positionsensitive detectors

    International Nuclear Information System (INIS)

    Berliner, R.; Mildner, D.F.R.; Pringle, O.A.

    1981-01-01

    The data acquisition speed and electronic stability of a charge division position-sensitive detector may be improved by using digital signal processing with a table look-up high speed multiply to form the charge division quotient. This digitization process introduces a positional quantization difficulty which reduces the detector position sensitivity. The degree of the digitization error is dependent on the pulse height spectrum of the detector and on the resolution or dynamic range of the system analog-to-digital converters. The effects have been investigated analytically and by computer simulation. The optimum algorithm for position sensing determination using 8-bit digitization and arithmetic has a digitization error of less than 1%. (orig.)

  15. Increasing the efficiency of digitization workflows for herbarium specimens

    Directory of Open Access Journals (Sweden)

    Melissa Tulig

    2012-07-01

    Full Text Available The New York Botanical Garden Herbarium has been databasing and imaging its estimated 7.3 million plant specimens for the past 17 years. Due to the size of the collection, we have been selectively digitizing fundable subsets of specimens, making successive passes through the herbarium with each new grant. With this strategy, the average rate for databasing complete records has been 10 specimens per hour. With 1.3 million specimens databased, this effort has taken about 130,000 hours of staff time. At this rate, to complete the herbarium and digitize the remaining 6 million specimens, another 600,000 hours would be needed. Given the current biodiversity and economic crises, there is neither the time nor money to complete the collection at this rate.Through a combination of grants over the last few years, The New York Botanical Garden has been testing new protocols and tactics for increasing the rate of digitization through combinations of data collaboration, field book digitization, partial data entry and imaging, and optical character recognition (OCR of specimen images. With the launch of the National Science Foundation’s new Advancing Digitization of Biological Collections program, we hope to move forward with larger, more efficient digitization projects, capturing data from larger portions of the herbarium at a fraction of the cost and time.

  16. Guideline on evaluation and acceptance of commercial grade digital equipment for nuclear safety applications

    International Nuclear Information System (INIS)

    1996-10-01

    Nuclear power plants are increasingly upgrading their instrumentation and control (I ampersand C) systems with commercial digital equipment, which allows them to continue meeting safety and reliability requirements while controlling operating costs. However, the use of commercial software-based devices for safety related applications has raised new issues that impact design, procurement, and licensing activities. This guideline describes a consistent, comprehensive approach for the evaluation and acceptance of commercial digital equipment for nuclear safety systems

  17. Research on Digital Product Modeling Key Technologies of Digital Manufacturing

    Institute of Scientific and Technical Information of China (English)

    DING Guoping; ZHOU Zude; HU Yefa; ZHAO Liang

    2006-01-01

    With the globalization and diversification of the market and the rapid development of Information Technology (IT) and Artificial Intelligence (AI), the digital revolution of manufacturing is coming. One of the key technologies in digital manufacturing is product digital modeling. This paper firstly analyzes the information and features of the product digital model during each stage in the product whole lifecycle, then researches on the three critical technologies of digital modeling in digital manufacturing-product modeling, standard for the exchange of product model data and digital product data management. And the potential signification of the product digital model during the process of digital manufacturing is concluded-product digital model integrates primary features of each stage during the product whole lifecycle based on graphic features, applies STEP as data exchange mechanism, and establishes PDM system to manage the large amount, complicated and dynamic product data to implement the product digital model data exchange, sharing and integration.

  18. Digital control application for the advanced boiling water reactor

    International Nuclear Information System (INIS)

    Fennern, L.E.; Pearson, T.; Wills, H.D.; Swire Rhodes, L.; Pearson, R.L.

    1986-01-01

    The Advanced Boiling Water Reactor (ABWR) is a 1300 MWe class Nuclear Power Plant whose design studies and demonstration tests are being performed by the three manufacturers, General Electric, Toshiba and Hitachi, under requirement specifications from the Tokyo Electric Power Company. The goals are to apply new technology to the BWR in order to achieve enhanced operational efficiencies, improved safety measures and cost reductions. In the plant instrumentation and control areas, traditional analog control equipment and wire cables will be replaced by distributed digital microprocessor based control units communicating with each other and the control room over fiber optic multiplexed data buses

  19. Nuclear power plant diagnostic system

    International Nuclear Information System (INIS)

    Prokop, K.; Volavy, J.

    1982-01-01

    Basic information is presented on diagnostic systems used at nuclear power plants with PWR reactors. They include systems used at the Novovoronezh nuclear power plant in the USSR, at the Nord power plant in the GDR, the system developed at the Hungarian VEIKI institute, the system used at the V-1 nuclear power plant at Jaslovske Bohunice in Czechoslovakia and systems of the Rockwell International company used in US nuclear power plants. These diagnostic systems are basically founded on monitoring vibrations and noise, loose parts, pressure pulsations, neutron noise, coolant leaks and acoustic emissions. The Rockwell International system represents a complex unit whose advantage is the on-line evaluation of signals which gives certain instructions for the given situation directly to the operator. The other described systems process signals using similar methods. Digitized signals only serve off-line computer analyses. (Z.M.)

  20. Fundamental BOP I and C systems structure in nuclear power plants

    International Nuclear Information System (INIS)

    Ishii, K.; Harada, H.; Yamamori, T.; Igarashi, K.; Arakida, T.

    2008-01-01

    Digital instrumentation and control (I and C) systems using distributed control systems (DCS) are essential elements for nuclear power plants (NPPs) seeking higher reliability, availability and maintainability. Hitachi can boast its broad new build and refurbishment project experience in Japan and other markets since the 1970s. Throughout its continuous involvement in NPP design, fabrication, construction and maintenance over 30 years, Hitachi has increasingly integrated digital I and C system with its own DCS suite. This paper focuses on the fundamental characteristics of Hitachi's Balance of Plant (BOP) I and C systems structure for new build nuclear projects. (author)

  1. Aspects regarding computer control of 15 N separation plant

    International Nuclear Information System (INIS)

    Kaucsar, M.; Cosma, V.; Axente, D.; Baldea, A.; Bendea, H.; Bunea, V

    2001-01-01

    In order to improve the efficiency of a separation plant the whole process must be automatically controlled. The plant has a single output - the isotopic product. This output is characterized by a complex function, which involves qualitative or/and quantitative properties of the product. There are two important inputs into the system, namely: the amount of the substances and compounds which supply the plant and the electric power consumption. Our first aim is to reduce the input/output ratio of the separation plant. On the other hand, by applying this automatic control system we can reduce the operating personnel also. The isotopic product is sampled and analyzed using a dedicated mass spectrometer. An overall closed loop through the separation plant including this mass spectrometer could be very efficient, but the theoretical analysis is too complex and it is very difficult to realize it in practice. Therefore, multiple local control loops are preferred to apply for each product correlated parameter. Between these parameters there are complex interdependencies, governed by differential equations. The computer is equipped with standard input/output hardware, but in order to use it in the complex feedback loops, extra input/output hardware must be added, namely, dedicated input/output module cards. Depending on the operating principle of the detectors and actuators the signals involved in the whole system are analog and digital. The majority of the sensors and transducers generates analog signals and only a few of them have digital output. The last case is typical for transducers specialized mainly for detecting the level of a parameter. Actuators also need analog or digital control signals, corresponding to their operating principles. The computer control of isotopic plant has a great advantage of being very flexible in implementing adequate control software with operator friendly interfacing routines. (authors)

  2. Maximum power point tracking in PV systems based on adaptive control and sliding mode control

    Directory of Open Access Journals (Sweden)

    Paula Andrea Ortiz-Valencia

    2015-01-01

    Full Text Available Los sistemas fotovoltaicos (PV son comúnmente controlados utilizando estructuras PI o PID, las cuales no pueden asegurar estabilidad global y un tiempo de establecimiento constante. Por esto, los algoritmos de optimización, e.g. Perturbar y Observar (P&O, son diseñados utilizando el tiempo de establecimiento más alto en el rango de operación, lo cual produce una búsqueda lenta del punto de máxima potencia (MPP para gran parte del rango de operación, introduciendo pérdidas dinámicas de potencia al sistema. Este artículo propone combinar un controlador adaptativo y un controlador de corriente por modos deslizantes (SMCC para garantizar estabilidad global y un tiempo de establecimiento constante para cualquier condición de operación, lo que permite incrementar la potencia generada en comparación con controladores PI y PID. El SMCC permite mitigar las perturbaciones del sistema y garantizar estabilidad global, mientras que el controlador adaptativo define la referencia del SMCC para asegurar un tiempo de estabilización constante. El diseño de la nueva estructura de control se soporta con análisis matemáticos y simulaciones realizadas en Matlab® para validar la robustez del sistema.

  3. Digital Pulser for Characterization and Diagnostic of Digital Spectrometers

    International Nuclear Information System (INIS)

    Jordanov, V.T.

    2013-01-01

    The concept and the realization of the digital pulser are presented. The digital pulser is implemented as a functional block of a digital spectrometer. The digital pulser provides noise free and distortion free measurement of the inherent electronic noise of the entire spectroscopy system. The digital pulser is introduced at the end of the signal processing chain and allows separate evaluation of the individual spectroscopy blocks. It offers the ability to characterize and diagnose problems of the digital pulse height analysers by grounding their inputs. The digital pulser does not interfere with the processing of the detector signals and does not contribute to the dead time and the pulse pile-up of the system. The digital pulser peaks are not affected by the presence of detector pulses and are stored in a separate histogram memory leaving the detector spectrum undistorted. (author)

  4. Digital Ethics/Going Digital.

    Science.gov (United States)

    Wilson, Bradley

    1996-01-01

    Finds that the recent National Press Photographers Association code of ethics can serve as a model for any photography staff. Discusses how digital imaging is becoming commonplace in classrooms, due to decreasing costs and easier software. Explains digital terminology. Concludes that time saved in the darkroom and at the printer is now spent on…

  5. Analyzing the decision making process of certifying digital control systems of nuclear power plants

    International Nuclear Information System (INIS)

    Yih, Swu; Fan, Chin-Feng

    2012-01-01

    Highlights: ► We have performed basic research in analyzing certification process and developed a regulatory decision making model for nuclear digital control system certification. The model views certification as an evidence–confidence conversion process. ► We have applied this model to analyze previous nuclear digital I and C certification experiences and obtained valuable insights. ► Furthermore, a prototype of a computer-aided licensing support system based on the model has been developed to enhance regulatory review efficiency. - Abstract: Safety-critical computing systems need regulators’ approval before operation. Such a permit issue process is called “certification”. Digital instrumentation and Control (I and C) certification in the nuclear domain has always been problematic and lengthy. Thus, the certification efficiency has always been a crucial concern to the applicant whose business depends on the regulatory decision. However, to our knowledge, there is little basic research on this topic. This study presents a Regulatory Decision-Making Model aiming at analyzing the characteristics and efficiency influence factors in a generic certification process. This model is developed from a dynamic operational perspective by viewing the certification process as an evidence–confidence conversion process. The proposed model is then applied to previous nuclear digital I and C certification experiences to successfully explain why some cases were successful and some were troublesome. Lessons learned from these cases provide invaluable insights regarding to the regulatory review activity. Furthermore, to utilize the insights obtained from the model, a prototype of a computer-aided licensing support system has been developed to speed up review evidence preparation and manipulation; thus, regulatory review efficiency can be further improved.

  6. Can We Teach Digital Natives Digital Literacy?

    Science.gov (United States)

    Ng, Wan

    2012-01-01

    In recent years, there has been much debate about the concept of digital natives, in particular the differences between the digital natives' knowledge and adoption of digital technologies in informal versus formal educational contexts. This paper investigates the knowledge about educational technologies of a group of undergraduate students…

  7. Design an optimal controller for nuclear reactor using a digital computer

    International Nuclear Information System (INIS)

    Saleh, F.M.A.

    1986-01-01

    An attempt is carried out to design an optimal controller, for a model nuclear reactor at one hand, and a model nuclear power plant at another hand using a digital computer. The design philosophy adopted was to specify the system dynamics in terms of a desired system transfer function, and realizing the design synthesis through state-variable feedback technique, thus ensuring both stability and optimization in the state space sense. The control design was also tested by carrying out digital simulation transient response runs (step, ramp, impulse, etc.) and agreement between the predicted desirable response and actual response of the overall design was achieved. Furthermore the performance of the controller is verified against a reference non-linear model for purposes of assessing the accuracy of the linearized approximation model. The results show that state-variable feedback policy can rank as an effective optimal technique for designing control algorithm for an on-line computer of a nuclear power plant. 41 figs. 43 refs

  8. Research on Methodology to Prioritize Critical Digital Assets based on Nuclear Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Wonjik; Kwon, Kookheui; Kim, Hyundoo [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

    2016-10-15

    Digital systems are used in nuclear facilities to monitor and control various types of field devices, as well as to obtain and store vital information. Therefore, it is getting important for nuclear facilities to protect digital systems from cyber-attack in terms of safety operation and public health since cyber compromise of these systems could lead to unacceptable radiological consequences. Based on KINAC/RS-015 which is a cyber security regulatory standard, regulatory activities for cyber security at nuclear facilities generally focus on critical digital assets (CDAs) which are safety, security, and emergency preparedness related digital assets. Critical digital assets are estimated over 60% among all digital assets in a nuclear power plant. Therefore, it was required to prioritize critical digital assets to improve efficiency of regulation and implementation. In this paper, the research status on methodology development to prioritize critical digital assets based on nuclear risk assessment will be introduced. In this paper, to derive digital asset directly affect accident, PRA results (ET, FT, and minimal cut set) are analyzed. According to result of analysis, digital systems related to CD are derived ESF-CCS (safety-related component control system) and Process-CCS (non-safety-related component control system) as well as Engineered Safety Features Actuation System (ESFAS). These digital assets can be identified Vital Digital Asset (VDA). Hereafter, to develop general methodology which was identified VDA related to accident among CDAs, (1) method using result of minimal cut set in PRA model will be studied and (2) method quantifying result of Digital I and C PRA which is performed to reflect all digital cabinet related to system in FT will be studied.

  9. Research on Methodology to Prioritize Critical Digital Assets based on Nuclear Risk Assessment

    International Nuclear Information System (INIS)

    Kim, Wonjik; Kwon, Kookheui; Kim, Hyundoo

    2016-01-01

    Digital systems are used in nuclear facilities to monitor and control various types of field devices, as well as to obtain and store vital information. Therefore, it is getting important for nuclear facilities to protect digital systems from cyber-attack in terms of safety operation and public health since cyber compromise of these systems could lead to unacceptable radiological consequences. Based on KINAC/RS-015 which is a cyber security regulatory standard, regulatory activities for cyber security at nuclear facilities generally focus on critical digital assets (CDAs) which are safety, security, and emergency preparedness related digital assets. Critical digital assets are estimated over 60% among all digital assets in a nuclear power plant. Therefore, it was required to prioritize critical digital assets to improve efficiency of regulation and implementation. In this paper, the research status on methodology development to prioritize critical digital assets based on nuclear risk assessment will be introduced. In this paper, to derive digital asset directly affect accident, PRA results (ET, FT, and minimal cut set) are analyzed. According to result of analysis, digital systems related to CD are derived ESF-CCS (safety-related component control system) and Process-CCS (non-safety-related component control system) as well as Engineered Safety Features Actuation System (ESFAS). These digital assets can be identified Vital Digital Asset (VDA). Hereafter, to develop general methodology which was identified VDA related to accident among CDAs, (1) method using result of minimal cut set in PRA model will be studied and (2) method quantifying result of Digital I and C PRA which is performed to reflect all digital cabinet related to system in FT will be studied

  10. Digital reactivity meter

    International Nuclear Information System (INIS)

    Jiang Zongbing

    1996-02-01

    The importance and the usual methods of reactivity measurement in a nuclear reactor are presented. Emphasis is put upon the calculation principle, software and hardware components, main specifications, application, as well as the features of the digital reactivity meter. The test results of operation in various reactors shown that the meter possess the following features: high accuracy, short response time, low output noise, high resolution, wide measuring range, simple and flexible to operate, high stability and reliability. In addition, the reactivity meter can save the measuring data automatically and have a perfect capability of self-verifying. It not only meet the requirement of the reactivity measurement in nuclear power plant, but also can be applied to various types of reactors. (1 tab.)

  11. Digital implementation of AMSACs at Harris and Robinson plants

    International Nuclear Information System (INIS)

    Burjorjee, D.; Stepps, D.

    1988-01-01

    The Code of Federal Regulations was altered in July 1984 to include a section on Requirements for Reduction of Risk from Anticipated Transients Without Scram Events for Light Water Cooled Nuclear Power Plants. For pressurized water reactors the code required equipment diverse from the reactor trip system to automatically initiate the auxiliary (or emergency) feedwater system and initiate a turbine trip under conditions indicative of an anticipated transient without scram (ATWS). The equipment in question is called ATWS mitigation system actuation circuitry (AMSAC). The AMSACs for Carolina Power and Light Company's Shearon Harris and Robinson power plants have been designed and built by Atomic Energy of Canada Limited (AECL) from commercially available components to meet stringent reliability requirements and minimize operational burdens

  12. Control system security in nuclear power plant

    International Nuclear Information System (INIS)

    Li Jianghai; Huang Xiaojin

    2012-01-01

    The digitalization and networking of control systems in nuclear power plants has brought significant improvements in system control, operation and maintenance. However, the highly digitalized control system also introduces additional security vulnerabilities. Moreover, the replacement of conventional proprietary systems with common protocols, software and devices makes these vulnerabilities easy to be exploited. Through the interaction between control systems and the physical world, security issues in control systems impose high risks on health, safety and environment. These security issues may even cause damages of critical infrastructures and threaten national security. The importance of control system security by reviewing several control system security incidents that happened in nuclear power plants was showed in recent years. Several key difficulties in addressing these security issues were described. Finally, existing researches on control system security and propose several promising research directions were reviewed. (authors)

  13. Digital recording system

    International Nuclear Information System (INIS)

    Chandra, A.K.; Deshpande, S.V.; Iyer, A.; Vaidya, U.W.

    1987-01-01

    A large number of critical process parameters in nuclear power plants have hitherto been monitored using electromechanical chart recorders. The reducing costs of electronics systems have led to a trend towards modernizing power plant control rooms by computerizing all the panel instrumentation. As a first step, it has been decided to develop a digital recording system to record the values of 48 process parameters. The system as developed and described in this report is more than a replacement for recorders; it offers substantial advantages in terms of lower overall system cost, excellent time resolution, accurate data and absolute synchronization for correlated signals. The system provides high speed recording of 48 process parameters, maintains historical records and permits retrieval and display of archival information on a colour monitor, a plotter and a printer. It is implemented using a front end data acquisition unit connected on a serial link to a PC-XT computer with 20 MB Winchester. The system offers an extremely user friendly man machine interaction, based on a hierarchical paged menu driven scheme. Softwre development for this system has been carried out using the C language. (author). 9 figs

  14. MDEP Common Position CP-DICWG-07. Common position on selection and use of industrial digital devices of limited functionality

    International Nuclear Information System (INIS)

    2014-01-01

    The nuclear power industry is increasingly interested in using industrial digital devices of limited functionality in systems important to safety, but that have not been developed specifically for use in nuclear power applications. These devices should meet certain specific requirements in order to be selected and used in systems important to safety at nuclear power plants. Typically, some of these devices are found embedded in plant components and actuating devices, e.g. sensing instrumentation, motors, pumps, actuators, breakers. The Digital Instrumentation and Controls Working Group (DICWG) has agreed that a common position on this topic is warranted given the increase of use of Digital I and C in new reactor designs, its safety implications, and the need to develop a common understanding from the perspectives of regulatory authorities. This action follows the DICWG examination of the regulatory requirements of the participating members and of relevant industry standards and IAEA documents. The DICWG proposes a common position based on its recent experience with the new reactor application reviews and operating plant issues

  15. Digitization and digital archiving a practical guide for librarians

    CERN Document Server

    Leggett, Elizabeth R

    2014-01-01

    Modern library patrons are embracing the ease with which information can be accessed digitally, and so many librarians are currently working toward making information available electronically. Digitization and Digital Archiving: A Practical Guide for Librarians is a comprehensive guide with step-by-step instructions for forming digital archives.

  16. Digital disruption ?syndromes.

    Science.gov (United States)

    Sullivan, Clair; Staib, Andrew

    2017-05-18

    The digital transformation of hospitals in Australia is occurring rapidly in order to facilitate innovation and improve efficiency. Rapid transformation can cause temporary disruption of hospital workflows and staff as processes are adapted to the new digital workflows. The aim of this paper is to outline various types of digital disruption and some strategies for effective management. A large tertiary university hospital recently underwent a rapid, successful roll-out of an integrated electronic medical record (EMR). We observed this transformation and propose several digital disruption "syndromes" to assist with understanding and management during digital transformation: digital deceleration, digital transparency, digital hypervigilance, data discordance, digital churn and post-digital 'depression'. These 'syndromes' are defined and discussed in detail. Successful management of this temporary digital disruption is important to ensure a successful transition to a digital platform. What is known about this topic? Digital disruption is defined as the changes facilitated by digital technologies that occur at a pace and magnitude that disrupt established ways of value creation, social interactions, doing business and more generally our thinking. Increasing numbers of Australian hospitals are implementing digital solutions to replace traditional paper-based systems for patient care in order to create opportunities for improved care and efficiencies. Such large scale change has the potential to create transient disruption to workflows and staff. Managing this temporary disruption effectively is an important factor in the successful implementation of an EMR. What does this paper add? A large tertiary university hospital recently underwent a successful rapid roll-out of an integrated electronic medical record (EMR) to become Australia's largest digital hospital over a 3-week period. We observed and assisted with the management of several cultural, behavioural and

  17. Guidelines for reliability analysis of digital systems in PSA context. Phase 3. Status report

    Energy Technology Data Exchange (ETDEWEB)

    Authen, S. [Risk Pilot AB, Stockholm (Sweden); Holmberg, J.-E. [VTT Technical Research Centre of Finland, Espoo (Finland)

    2013-03-15

    Digital protection and control systems appear as upgrades in older plants, and are commonplace in new nuclear power plants. To assess the risk of nuclear power plant operation and to determine the risk impact of digital systems, there is a need to quantitatively assess the reliability of the digital systems in a justifiable manner. In 2007, the OECD/NEA CSNI directed the Working Group on Risk Assessment (WGRisk) to set up a task group to coordinate an activity in this field. One of the recommendations was to develop a taxonomy of failure modes of digital components for the purposes of probabilistic safety assessment (PSA), resulting in a follow-up task group called DIGREL. The taxonomy will be the basis of future modelling and quantification efforts. It will also help define a structure for data collection and to review PSA studies. This an interim report of the project. A draft guidelines document on the failure modes taxonomy has been developed. The taxonomy is rather complete covering all levels from the system level down to module and basic component level failure modes, including hardware and software aspects. There are still open issues to be resolved by the task group, especially related to I and C unit and module level taxonomy. In a parallel Nordic activity, a comparison of Nordic experiences and a literature review on main international references has been performed. The study showed a wide range of approaches and solutions to the challenges given by digital I and C, and also indicated that no state-of-the-art currently exists. An existing simplified PSA model has been complemented with fault tree models for a four-redundant distributed protection system in order to study and demonstrate the effect of design features and modelling approaches. The model has been used to test the effect of CCF modelling, fail-safe principle and voting logic. A comparison has been made between unit-level and module-level modelling. (Author)

  18. Guidelines for reliability analysis of digital systems in PSA context. Phase 3. Status report

    International Nuclear Information System (INIS)

    Authen, S.; Holmberg, J.-E.

    2013-03-01

    Digital protection and control systems appear as upgrades in older plants, and are commonplace in new nuclear power plants. To assess the risk of nuclear power plant operation and to determine the risk impact of digital systems, there is a need to quantitatively assess the reliability of the digital systems in a justifiable manner. In 2007, the OECD/NEA CSNI directed the Working Group on Risk Assessment (WGRisk) to set up a task group to coordinate an activity in this field. One of the recommendations was to develop a taxonomy of failure modes of digital components for the purposes of probabilistic safety assessment (PSA), resulting in a follow-up task group called DIGREL. The taxonomy will be the basis of future modelling and quantification efforts. It will also help define a structure for data collection and to review PSA studies. This an interim report of the project. A draft guidelines document on the failure modes taxonomy has been developed. The taxonomy is rather complete covering all levels from the system level down to module and basic component level failure modes, including hardware and software aspects. There are still open issues to be resolved by the task group, especially related to I and C unit and module level taxonomy. In a parallel Nordic activity, a comparison of Nordic experiences and a literature review on main international references has been performed. The study showed a wide range of approaches and solutions to the challenges given by digital I and C, and also indicated that no state-of-the-art currently exists. An existing simplified PSA model has been complemented with fault tree models for a four-redundant distributed protection system in order to study and demonstrate the effect of design features and modelling approaches. The model has been used to test the effect of CCF modelling, fail-safe principle and voting logic. A comparison has been made between unit-level and module-level modelling. (Author)

  19. Digital Natives and Digital Divide: Analysing Perspective for Emerging Pedagogy

    Science.gov (United States)

    Onye, Uriel U.; Du, Yunfei

    2016-01-01

    This paper addresses the concepts of digital natives and digital divide from the perspective of the digital outsiders (part of digital natives). It takes a critical look at the implications of available ICT in both developed and underdeveloped countries in the fight against digital divide. The major contribution to literature is by drawing…

  20. Visual Characterization of VX Droplets on Plant Foliage

    Science.gov (United States)

    2016-07-01

    droplets were dispensed onto plant leaves using a high-precision syringe. Digital photographs of the droplets were taken at intervals, saved, and...purposes of advertisement . Approved for public release; distribution is unlimited Acknowledgments The authors would like to thank Dr...alcohol (CAS no. 67-63-0) was used as an extractant. Miracle-Gro Water Soluble All Purpose Plant Food (Scotts Company; Marysville, OH) fertilizer

  1. Risk assessment of safety data link and network communication in digital safety feature control system of nuclear power plant

    International Nuclear Information System (INIS)

    Lee, Sang Hun; Son, Kwang Seop; Jung, Wondea; Kang, Hyun Gook

    2017-01-01

    Highlights: • Safety data communication risk assessment framework and quantitative scheme were proposed. • Fault-tree model of ESFAS unavailability due to safety data communication failure was developed. • Safety data link and network risk were assessed based on various ESF-CCS design specifications. • The effect of fault-tolerant algorithm reliability of safety data network on ESFAS unavailability was assessed. - Abstract: As one of the safety-critical systems in nuclear power plants (NPPs), the Engineered Safety Feature-Component Control System (ESF-CCS) employs safety data link and network communication for the transmission of safety component actuation signals from the group controllers to loop controllers to effectively accommodate various safety-critical field controllers. Since data communication failure risk in the ESF-CCS has yet to be fully quantified, the ESF-CCS employing data communication systems have not been applied in NPPs. This study therefore developed a fault tree model to assess the data link and data network failure-induced unavailability of a system function used to generate an automated control signal for accident mitigation equipment. The current aim is to provide risk information regarding data communication failure in a digital safety feature control system in consideration of interconnection between controllers and the fault-tolerant algorithm implemented in the target system. Based on the developed fault tree model, case studies were performed to quantitatively assess the unavailability of ESF-CCS signal generation due to data link and network failure and its risk effect on safety signal generation failure. This study is expected to provide insight into the risk assessment of safety-critical data communication in a digitalized NPP instrumentation and control system.

  2. Digital subtraktion

    DEFF Research Database (Denmark)

    Mussmann, Bo Redder

    2004-01-01

    Digital subtraktion er en metode til at fjerne uønskede oplysninger i et røntgenbillede. Subtraktionsteknikken bruges primært i forbindelse med angiografi hvor man kun er interesseret i at se selve karret. Derfor er digital subtraktion i daglig tale synonymt med DSA eller DVI – hhv. Digital...... Subtraction Angiography eller Digital Vascular Imaging. Benævnelserne er to røntgenfirmaers navn for den samme teknik. Digital subtraktion kræver speciel software, samt at apparaturet kan eksponere i serier....

  3. CANDU Digital Control Computer upgrade options

    International Nuclear Information System (INIS)

    De Jong, M.S.; De Grosbois, J.; Qian, T.

    1997-01-01

    This paper reviews the evolution of Digital Control Computers (DCC) in CANDU power plants to the present day. Much of this evolution has been to meeting changing control or display requirements as well as the replacement of obsolete, or old and less reliable technology with better equipment that is now available. The current work at AECL and Canadian utilities to investigate DCC upgrade options, alternatives, and strategies are examined. The dependence of a particular upgrade strategy on the overall plant refurbishment plans are also discussed. Presently, the upgrade options range from replacement of individual obsolete system components, to replacement of the entire DCC hardware without changing the software, to complete replacement of the DCCs with a functionally equivalent system using new control computer equipment and software. Key issues, constraints and objectives associated with these DCC upgrade options are highlighted. (author)

  4. Guidelines on Training, Examination and Certification in Digital Industrial Radiology Testing (RT-D)

    International Nuclear Information System (INIS)

    2015-01-01

    The IAEA promotes industrial applications of non-destructive testing (NDT) technologies. NDT methods are primarily used for the detection, location and sizing of surface and internal defects in, for example, welds, castings, forging, composite materials and concrete. Various NDT methods are also used in the preventive maintenance of nuclear power plants, aircraft and bridges. Thus, NDT technology contributes significantly to the improvement of the quality of industrial products and the integrity of equipment and plants. The introduction of powerful computers and reliable imaging technology has had significant impact on traditional, nuclear based NDT methods. During the introduction phase in digital industrial radiography (DIR), the digitization of films provided economy of storage, efficiency of communication and accuracy of dimensional measurement. NDT laboratories are progressing rapidly with the digitalization of NDT data. New radiologic imaging techniques in DIR, using image intensifier systems, computed radiography with phosphor imaging plates and digital detector arrays, have increased the capacity for visualization of defects and have revealed new potential for accurate evaluation and measurement. The development of DIR has been of continuing interest to the IAEA and national NDT societies in recent years. This has led to the formation of projects on the development and application of advanced industrial radiography and tomography techniques under the IAEA Regional Co-operative Agreement for Research, Development and Training Related to Nuclear Science and Technology. This publication is intended to provide resource material to support vocational training to NDT radiographers on digital industrial radiography and to help NDT training centres and certification bodies in Member States to establish their own courses, curricula and certification systems in this technology

  5. Digital Citizenship Means Character Education for the Digital Age

    Science.gov (United States)

    Ohler, Jason

    2012-01-01

    The reality of students' cyber lives has thrust upon educators a new approach: creating character education programs tuned to digital youth that are proactive and aggressive. This will help integrate students' digital activities within the context of the communities in which they live, both local and digital. The digital age beckons a new era of…

  6. Real-time simulation of MHD/steam power plants by digital parallel processors

    International Nuclear Information System (INIS)

    Johnson, R.M.; Rudberg, D.A.

    1981-01-01

    Attention is given to a large FORTRAN coded program which simulates the dynamic response of the MHD/steam plant on either a SEL 32/55 or VAX 11/780 computer. The code realizes a detailed first-principle model of the plant. Quite recently, in addition to the VAX 11/780, an AD-10 has been installed for usage as a real-time simulation facility. The parallel processor AD-10 is capable of simulating the MHD/steam plant at several times real-time rates. This is desirable in order to develop rapidly a large data base of varied plant operating conditions. The combined-cycle MHD/steam plant model is discussed, taking into account a number of disadvantages. The disadvantages can be overcome with the aid of an array processor used as an adjunct to the unit processor. The conversion of some computations for real-time simulation is considered

  7. Digital Insights

    DEFF Research Database (Denmark)

    Knudsen, Gry Høngsmark

    , by incorporating media as both channel, frame, and apparatus for advertising response, the dissertation brings into attention that more aspects than the text-reader relationship influence ad response. Finally, the dissertation proposes the assemblage approach for exploring big data in consumer culture research...... and practices with digital media, when they meet and interpret advertising. Through studies of advertising response on YouTube and experiments with consumers’ response to digitally manipulated images, the dissertation shows how digital media practices facilitate polysemic and socially embedded advertising......This dissertation forwards the theory of digital consumer-response as a perspective to examine how digital media practices influence consumers’ response to advertising. Digital consumer-response is a development of advertising theory that encompasses how consumers employ their knowledge...

  8. Results and Insights on the Impact of Smoke on Digital Instrumentation and Control

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T. J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nowlen, S. P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2001-01-31

    Smoke can cause interruptions and upsets in active electronics. Because nuclear power plants are replacing analog with digital instrumentation and control systems, qualification guidelines for new systems are being reviewed for severe environments such as smoke and electromagnetic interference. Active digital systems, individual components, and active circuits have been exposed to smoke in a program sponsored by the U.S. Nuclear Regulatory Commission. The circuits and systems were all monitored during the smoke exposure, indicating any immediate effects of the smoke. The major effect of smoke has been to increase leakage currents (through circuit bridging across contacts and leads) and to cause momentary upsets and failures in digital systems. This report summarizes two previous reports and presents new results from conformal coating, memory chip, and hard drive tests. The report describes practices for mitigation of smoke damage through digital system design, fire barriers, ventilation, fire suppressants, and post fire procedures.

  9. Digital information culture the individual and society in the digital age

    CERN Document Server

    Tredinnick, Luke

    2008-01-01

    Digital Information Culture is an introduction to the cultural, social and political impact of digital information and digital resources. The book is organised around themes, rather than theories and is arranged into three sections: culture, society and the individual. Each explores key elements of the social, cultural and political impact of digital information. The culture section outlines the origins of cyber culture in fifties pulp-fiction through to the modern day. It explores the issues of information overload, the threat of a digital dark age, and the criminal underbelly of digital culture. Section two, society, explores the economic and social impact of digital information, outlining key theories of the Information Age. Section three explores the impact of digital information and digital resources on the individual, exploring the changing nature of identity in a digital world. Written by a leading author in the field Focuses on digital information and its social, cultural and political impact is uniqu...

  10. Digital printing

    Science.gov (United States)

    Sobotka, Werner K.

    1997-02-01

    Digital printing is described as a tool to replace conventional printing machines completely. Still this goal was not reached until now with any of the digital printing technologies to be described in the paper. Productivity and costs are still the main parameters and are not really solved until now. Quality in digital printing is no problem anymore. Definition of digital printing is to transfer digital datas directly on the paper surface. This step can be carried out directly or with the use of an intermediate image carrier. Keywords in digital printing are: computer- to-press; erasable image carrier; image carrier with memory. Digital printing is also the logical development of the new digital area as it is pointed out in Nicholas Negropotes book 'Being Digital' and also the answer to networking and Internet technologies. Creating images text and color in one country and publishing the datas in another country or continent is the main advantage. Printing on demand another big advantage and last but not least personalization the last big advantage. Costs and being able to coop with this new world of prepress technology is the biggest disadvantage. Therefore the very optimistic growth rates for the next few years are really nonexistent. The development of complete new markets is too slow and the replacing of old markets is too small.

  11. Digital squares

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Kim, Chul E

    1988-01-01

    Digital squares are defined and their geometric properties characterized. A linear time algorithm is presented that considers a convex digital region and determines whether or not it is a digital square. The algorithm also determines the range of the values of the parameter set of its preimages....... The analysis involves transforming the boundary of a digital region into parameter space of slope and y-intercept...

  12. Digital skrivedidaktik

    DEFF Research Database (Denmark)

    Digital skrivedidaktik består af to dele. Første del præsenterer teori om skrivekompetence og digital skrivning. Digital skrivning er karakteriseret ved at tekster skrives på computer og med digitale værktøjer, hvilket ændrer skrivningens traditionelle praksis, produkt og processer. Hvad er digital...... om elevens skriveproces) og Blogskrivning (der styrker eleverne i at bruge blogs i undervisningen)....

  13. Cost Model for Digital Curation: Cost of Digital Migration

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2009-01-01

    The Danish Ministry of Culture is currently funding a project to set up a model for costing preservation of digital materials held by national cultural heritage institutions. The overall objective of the project is to provide a basis for comparing and estimating future financial requirements...... for digital preservation and to increase cost effectiveness of digital preservation activities. In this study we describe an activity based costing methodology for digital preservation based on the OAIS Reference Model. In order to estimate the cost of digital migrations we have identified cost critical...

  14. Reliability Evaluation Methodologies of Fault Tolerant Techniques of Digital I and C Systems in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, Bo Gyung; Kang, Hyun Gook; Seong, Poong Hyun; Lee, Seung Jun

    2011-01-01

    Since the reactor protection system was replaced from analog to digital, digital reactor protection system has 4 redundant channels and each channel has several modules. It is necessary for various fault tolerant techniques to improve availability and reliability due to using complex components in DPPS. To use the digital system, it is necessary to improve the reliability and availability of a system through fault-tolerant techniques. Several researches make an effort to effects of fault tolerant techniques. However, the effects of fault tolerant techniques have not been properly considered yet in most fault tree models. Various fault-tolerant techniques, which used in digital system in NPPs, should reflect in fault tree analysis for getting lower system unavailability and more reliable PSA. When fault-tolerant techniques are modeled in fault tree, categorizing the module to detect by each fault tolerant techniques, fault coverage, detection period and the fault recovery should be considered. Further work will concentrate on various aspects for fault tree modeling. We will find other important factors, and found a new theory to construct the fault tree model

  15. Digital preservation

    CERN Document Server

    Deegan, Marilyn

    2013-01-01

    Digital preservation is an issue of huge importance to the library and information profession right now. With the widescale adoption of the internet and the rise of the world wide web, the world has been overwhelmed by digital information. Digital data is being produced on a massive scale by individuals and institutions: some of it is born, lives and dies only in digital form, and it is the potential death of this data, with its impact on the preservation of culture, that is the concern of this book. So how can information professionals try to remedy this? Digital preservation is a complex iss

  16. [Study on spectral detection of green plant target].

    Science.gov (United States)

    Deng, Wei; Zhao, Chun-jiang; He, Xiong-kui; Chen, Li-ping; Zhang, Lu-da; Wu, Guang-wei; Mueller, J; Zhai, Chang-yuan

    2010-08-01

    Weeds grow scatteredly in fields, where many insentient objects exist, for example, withered grasses, dry twig and barriers. In order to improve the precision level of spraying, it is important to study green plant detecting technology. The present paper discussed detecting method of green plant by using spectral recognizing technology, because of the real-time feature of spectral recognition. By analyzing the reflectivity difference between each of the two sides of the "red edge" of the spectrum from plants and surrounding environment, green plant discriminat index (GPDI) is defined as the value which equals the reflectivity ratio at the wavelength of 850 nm divided by the reflectivity ratio at the wavelength of 650 nm. The original spectral data of green plants and the background were measured by using the handhold FieldSpec 3 Spectroradiometer manufactured by ASD Inc. in USA. The spectral data were processed to get the reflectivity of each measured objects and to work out the GPDI thereof as well. The classification model of green plant and its background was built up using decision tree method in order to obtain the threshold of GPDI to distinguish green plants and the background. The threshold of GPDI was chosen as 5.54. The detected object was recognized as green plant when it is GPDI>GPDITH, and vice versa. Through another test, the accuracy rate was verified which was 100% by using the threshold. The authors designed and developed the green plant detector based on single chip microcomputer (SCM) "AT89S51" and photodiode "OPT101" to realize detecting green plants from the background. After passing through two optical filters, the center wavelengths of which are 650 and 850 nm respectively, the reflected light from measured targets was detected by two photodiodes and converted into electrical signals. These analog signals were then converted to digital signals via an analog-to-digital converter (ADS7813) after being amplified by a signal amplifier (OP400

  17. Data Driven Synthesis of Three Term Digital Controllers

    Science.gov (United States)

    Keel, Lee H.; Mitra, Sandipan; Bhattacharyya, Shankar P.

    This paper presents a method for digital PID and first order controller synthesis based on frequency domain data alone. The techniques given here first determine all stabilizing controllers from measurement data. In both PID and first order controller cases, the only information required are frequency domain data (Nyquist-Bode data) and the number of open-loop RHP poles. Specifically no identification of the plant model is required. Examples are given for illustration.

  18. Employing airborne multispectral digital imagery to map Brazilian pepper infestation in south Texas.

    Science.gov (United States)

    A study was conducted in south Texas to determine the feasibility of using airborne multispectral digital imagery for differentiating the invasive plant Brazilian pepper (Schinus terebinthifolius) from other cover types. Imagery obtained in the visible, near infrared, and mid infrared regions of th...

  19. Digital academia: How higher education is affected by digital technology

    OpenAIRE

    Eriksmo, Anton; Sundberg, Johan

    2016-01-01

    Digital technology in higher education is constantly evolving. Understanding the effects of digital technology is important for higher education institutions in order to make good investments of digital technology. Previous research has focused on learning, teaching or the organization and the relation between one of these aspects and digital technology, thereby missing a broader understanding of how materiality in digital technology affects higher education. In this study themed interviews w...

  20. Digital rights management for digital cinema

    Science.gov (United States)

    Kirovski, Darko; Peinado, Marcus; Petitcolas, Fabien A. P.

    2001-12-01

    There is a wide consensus among the feature film production studios that the Internet era brings a new paradigm for film distribution to cinemas worldwide. The benefits of digital cinema to both producers and cinemas are numerous: significantly lower distribution and maintenance costs, immediate access to film libraries, higher presentation quality, and strong potential for developing new business models. Despite these advantages, the studios are still reluctant to jump into the digital age. The main showstopper for digital cinema is the danger of widespread piracy. Piracy already costs Hollywood an estimated two billion dollars annually and digital cinema without proper copyright enforcement could increase this number. In this paper, we present a copyright management system that aims at providing the set of necessary security tools: standard cryptographic primitives and copyright protection mechanisms that enable a reliable and secure feature film delivery system.

  1. Cognitive Hacking and Digital Government: Digital Identity

    Directory of Open Access Journals (Sweden)

    Paul Thompson

    2004-04-01

    Full Text Available Recently the National Center for Digital Government held a workshop on "The Virtual Citizen: Identity, Autonomy, and Accountability: A Civic Scenario Exploration of the Role of Identity in On-Line. Discussions at the workshop focused on five scenarios for future authentication policies with respect to digital identity. The underlying technologies considered for authentication were: biometrics: cryptography, with a focus on digital signatures; secure processing/computation; and reputation systems. Most discussion at the workshop focused on issues related to authentication of users of digital government, but, as implied by the inclusion of a scenario related to ubiquitous identity theft, there was also discussion of problems related to misinformation, including cognitive hacking. Cognitive hacking refers to a computer or information system attack that relies on changing human users' perceptions and corresponding behaviors in order to succeed. This paper describes cognitive hacking, suggests countermeasures, and discusses the implications of cognitive hacking for identity in digital government. In particular, spoofing of government websites and insider misuse are considered.

  2. Identification of the vital digital assets based on PSA results analysis

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Moon Kyoung; Seong, Poong Hyun [KAIST, Daejeon (Korea, Republic of); Son, Han Seong [Joongbu Univiersity, Geumsan (Korea, Republic of); Kim, Hyundoo [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

    2016-10-15

    As the main systems for managing totally about the operation, control, monitoring, measurement, and safety function in an emergency, instrumentation and control systems (I and C) in nuclear power plants have been digitalized gradually for the precise operation and its convenience. The digitalization of infrastructure makes systems vulnerable to cyber threats and hybrid attacks. According to ICS-CERT report, as time goes by, the number of vulnerabilities in ICS industries increases rapidly. Recently, due to the digitalization of I and C, it has begun to rise the need of cyber security in the digitalized I and C in NPPs. However, there are too many critical digital assets (CDAs) in NPPs. More than 60% of the total critical systems are digital system. Addressing more than 100 security controls for each CDA needs too much effort for both licensee and inspector. It is necessary to focus on more significant CDAs for effective regulation. Probabilistic Safety Analysis (PSA) results are analyzed in order to identify more significant CDAs which could evoke an accident of NPPs by digital malfunction or cyber-attacks. By eliciting minimal cut sets using fault tree analyses, accident-related CDAs are drawn. Also the CDAs that must be secured from outsiders are elicited in case of some accident scenario. It is expected that effective cyber security regulation based on the graded approach can be implemented. Furthermore, defense-in-depth of digital assets for NPPs safety can be built up. Digital technologies such as computers, control systems, and data networks currently play essential roles in modern NPPs. Further, the introduction of new digitalized technologies is also being considered. These digital technologies make the operation of NPPs more convenient and economical; however, they are inherently susceptible to problems such as digital malfunction of components or cyber-attacks. Recently, needs for cyber security on digitalized nuclear Instrumentation and Control (I and C

  3. Identification of the vital digital assets based on PSA results analysis

    International Nuclear Information System (INIS)

    Choi, Moon Kyoung; Seong, Poong Hyun; Son, Han Seong; Kim, Hyundoo

    2016-01-01

    As the main systems for managing totally about the operation, control, monitoring, measurement, and safety function in an emergency, instrumentation and control systems (I and C) in nuclear power plants have been digitalized gradually for the precise operation and its convenience. The digitalization of infrastructure makes systems vulnerable to cyber threats and hybrid attacks. According to ICS-CERT report, as time goes by, the number of vulnerabilities in ICS industries increases rapidly. Recently, due to the digitalization of I and C, it has begun to rise the need of cyber security in the digitalized I and C in NPPs. However, there are too many critical digital assets (CDAs) in NPPs. More than 60% of the total critical systems are digital system. Addressing more than 100 security controls for each CDA needs too much effort for both licensee and inspector. It is necessary to focus on more significant CDAs for effective regulation. Probabilistic Safety Analysis (PSA) results are analyzed in order to identify more significant CDAs which could evoke an accident of NPPs by digital malfunction or cyber-attacks. By eliciting minimal cut sets using fault tree analyses, accident-related CDAs are drawn. Also the CDAs that must be secured from outsiders are elicited in case of some accident scenario. It is expected that effective cyber security regulation based on the graded approach can be implemented. Furthermore, defense-in-depth of digital assets for NPPs safety can be built up. Digital technologies such as computers, control systems, and data networks currently play essential roles in modern NPPs. Further, the introduction of new digitalized technologies is also being considered. These digital technologies make the operation of NPPs more convenient and economical; however, they are inherently susceptible to problems such as digital malfunction of components or cyber-attacks. Recently, needs for cyber security on digitalized nuclear Instrumentation and Control (I and C

  4. Plant Modernization Programs

    International Nuclear Information System (INIS)

    O'Hara, John

    2004-01-01

    Most nuclear plants were designed and built from the 1960's through the 1990's. These plants employ predominantly analog instrumentation and control (I and C) technology, and their control rooms are made up of primarily hardwired controls (e.g., switches, knobs and handles) and displays (e.g., gauges, linear scales and indicator lights). Over the past several years, these plants have been modernized with digital I and C and computer-based human-system interfaces (HSIs) such as software-based process controls, touch-screen interfaces and large-screen, overview displays. As these computer based HIS technologies are integrated into control rooms based on conventional technology, hybrid control rooms are created. The paper summarizes lessons learned from the study of plant modernization programs over the past ten years so that they can be used to help improve the modification process. While the research focused on the impact of technology change on human performance, a number of organizational and programmatic issues were observed as well. Eleven lessons learned are presented

  5. Cognitive Hacking and Digital Government: Digital Identity

    OpenAIRE

    Paul Thompson

    2004-01-01

    Recently the National Center for Digital Government held a workshop on "The Virtual Citizen: Identity, Autonomy, and Accountability: A Civic Scenario Exploration of the Role of Identity in On-Line. Discussions at the workshop focused on five scenarios for future authentication policies with respect to digital identity. The underlying technologies considered for authentication were: biometrics: cryptography, with a focus on digital signatures; secure processing/computation; and reputation syst...

  6. Technical basis for acceptance criteria on the susceptibility of digital systems to electromagnetic interference

    International Nuclear Information System (INIS)

    Ewing, P.D.; Korsah, K.; Antonescu, C.

    1992-01-01

    This paper discusses the development of the technical basis for establishing acceptance criteria on the susceptibility of digital systems to electromagnetic interference (EMI). The effort is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed with the application of digital instrumentation and controls systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic voltage levels, thereby leading to the risk of susceptibility when spurious interference is misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and their impact on other nearby circuits and systems. Then, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related problems associated with EMI will be greatly reduced

  7. The Signal Validation method of Digital Process Instrumentation System on signal conditioner for SMART

    International Nuclear Information System (INIS)

    Moon, Hee Gun; Park, Sang Min; Kim, Jung Seon; Shon, Chang Ho; Park, Heui Youn; Koo, In Soo

    2005-01-01

    The function of PIS(Process Instrumentation System) for SMART is to acquire the process data from sensor or transmitter. The PIS consists of signal conditioner, A/D converter, DSP(Digital Signal Process) and NIC(Network Interface Card). So, It is fully digital system after A/D converter. The PI cabinet and PDAS(Plant Data Acquisition System) in commercial plant is responsible for data acquisition of the sensor or transmitter include RTD, TC, level, flow, pressure and so on. The PDAS has the software that processes each sensor data and PI cabinet has the signal conditioner, which is need for maintenance and test. The signal conditioner has the potentiometer to adjust the span and zero for test and maintenance. The PIS of SMART also has the signal conditioner which has the span and zero adjust same as the commercial plant because the signal conditioner perform the signal condition for AD converter such as 0∼10Vdc. But, To adjust span and zero is manual test and calibration. So, This paper presents the method of signal validation and calibration, which is used by digital feature in SMART. There are I/E(current to voltage), R/E(resistor to voltage), F/E(frequency to voltage), V/V(voltage to voltage). Etc. In this paper show only the signal validation and calibration about I/E converter that convert level, pressure, flow such as 4∼20mA into signal for AD conversion such as 0∼10Vdc

  8. Digital Natives and Digital Immigrants: Teaching with Technology

    Science.gov (United States)

    Martin, Ellen Marie Peterson

    2011-01-01

    Education is witnessing an increasing demand for technology use in the classroom. At the same time, new teachers are entering the profession in high numbers, some being labeled as "Digital Natives" while others are labeled "Digital Immigrants". This qualitative case study investigated the technology practices of Digital Native and Digital…

  9. [Constructing 3-dimensional colorized digital dental model assisted by digital photography].

    Science.gov (United States)

    Ye, Hong-qiang; Liu, Yu-shu; Liu, Yun-song; Ning, Jing; Zhao, Yi-jiao; Zhou, Yong-sheng

    2016-02-18

    To explore a method of constructing universal 3-dimensional (3D) colorized digital dental model which can be displayed and edited in common 3D software (such as Geomagic series), in order to improve the visual effect of digital dental model in 3D software. The morphological data of teeth and gingivae were obtained by intra-oral scanning system (3Shape TRIOS), constructing 3D digital dental models. The 3D digital dental models were exported as STL files. Meanwhile, referring to the accredited photography guide of American Academy of Cosmetic Dentistry (AACD), five selected digital photographs of patients'teeth and gingivae were taken by digital single lens reflex camera (DSLR) with the same exposure parameters (except occlusal views) to capture the color data. In Geomagic Studio 2013, after STL file of 3D digital dental model being imported, digital photographs were projected on 3D digital dental model with corresponding position and angle. The junctions of different photos were carefully trimmed to get continuous and natural color transitions. Then the 3D colorized digital dental model was constructed, which was exported as OBJ file or WRP file which was a special file for software of Geomagic series. For the purpose of evaluating the visual effect of the 3D colorized digital model, a rating scale on color simulation effect in views of patients'evaluation was used. Sixteen patients were recruited and their scores on colored and non-colored digital dental models were recorded. The data were analyzed using McNemar-Bowker test in SPSS 20. Universal 3D colorized digital dental model with better color simulation was constructed based on intra-oral scanning and digital photography. For clinical application, the 3D colorized digital dental models, combined with 3D face images, were introduced into 3D smile design of aesthetic rehabilitation, which could improve the patients' cognition for the esthetic digital design and virtual prosthetic effect. Universal 3D colorized

  10. Seamless Digital Environment - Plan for Data Analytics Use Case Study

    International Nuclear Information System (INIS)

    Oxstrand, Johanna Helene; Bly, Aaron Douglas

    2016-01-01

    The U.S Department of Energy Light Water Reactor Sustainability (LWRS) Program initiated research in to what is needed in order to provide a roadmap or model for Nuclear Power Plants to reference when building an architecture that can support the growing data supply and demand flowing through their networks. The Digital Architecture project published report Digital Architecture Planning Model (Oxstrand et. al, 2016) discusses things to consider when building an architecture to support the increasing needs and demands of data throughout the plant. Once the plant is able to support the data demands it still needs to be able to provide the data in an easy, quick and reliable method. A common method is to create a ''one stop shop'' application that a user can go to get all the data they need. The creation of this leads to the need of creating a Seamless Digital Environment (SDE) to integrate all the ''siloed'' data. An SDE is the desired perception that should be presented to users by gathering the data from any data source (e.g., legacy applications and work management systems) without effort by the user. The goal for FY16 was to complete a feasibility study for data mining and analytics for employing information from computer-based procedures enabled technologies for use in developing improved business analytics. The research team collaborated with multiple organizations to identify use cases or scenarios, which could be beneficial to investigate in a feasibility study. Many interesting potential use cases were identified throughout the FY16 activity. Unfortunately, due to factors out of the research team's control, none of the studies were initiated this year. However, the insights gained and the relationships built with both PVNGS and NextAxiom will be valuable when moving forward with future research. During the 2016 annual Nuclear Information Technology Strategic Leadership (NITSL) group meeting it was identified would be very beneficial to the industry to

  11. Materialising digital collecting: An extended view of digital materiality

    OpenAIRE

    Mardon, Rebecca; Belk, Russell

    2018-01-01

    If digital objects are abundant and ubiquitous, why should consumers pay for, much less collect them? The qualities of digital code present numerous challenges for collecting, yet digital collecting can and does occur. We explore the role of companies in constructing digital consumption objects that encourage and support collecting behaviours, identifying material configuration techniques that materialise these objects as elusive and authentic. Such techniques, we argue, may facilitate those ...

  12. Digital Natives: Creating Emergent Exhibitions through Digital Technologies

    DEFF Research Database (Denmark)

    Smith, Rachel Charlotte; Iversen, Ole Sejer; Dindler, Christian

    2011-01-01

    . In this way, digital technology can contribute to the creation of emergent exhibitions in which the exhibition is created in dialogue between audiences and the museum. We present experiences from a current research project, the Digital Natives exhibition, in which digital technology was designed......Digital Technology can support the creation of dialogical spaces in the museum, both playful and reflective, that allow audiences to engage in the ongoing construction and reproduction of cultural heritage creating novel connections between self and others and between past, present and future...... as an integral part of the exhibition to encourage dialogue between audiences and the exhibition materials and thereby investigate how the exhibition emerge as a result of this dialogic co-construction inside the exhibition space. In short, the opportunities offered by digital technologies prompts us to consider...

  13. Digital image processing of mandibular trabeculae on radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Ogino, Toshi

    1987-06-01

    The present study was aimed to reveal the texture patterns of the radiographs of the mandibular trabeculae by digital image processing. The 32 cases of normal subjects and the 13 cases of patients with mandibular diseases of ameloblastoma, primordial cysts, squamous cell carcinoma and odontoma were analyzed by their intra-oral radiographs in the right premolar regions. The radiograms were digitized by the use of a drum scanner densitometry method. The input radiographic images were processed by a histogram equalization method. The result are as follows : First, the histogram equalization method enhances the image contrast of the textures. Second, the output images of the textures for normal mandible-trabeculae radiograms are of network pattern in nature. Third, the output images for the patients are characterized by the non-network pattern and replaced by the patterns of the fabric texture, intertwined plants (karakusa-pattern), scattered small masses and amorphous texture. Thus, these results indicates that the present digital image system is expected to be useful for revealing the texture patterns of the radiographs and in the future for the texture analysis of the clinical radiographs to obtain quantitative diagnostic findings.

  14. Enabling Digital Literacy

    DEFF Research Database (Denmark)

    Ryberg, Thomas; Georgsen, Marianne

    2010-01-01

    There are some tensions between high-level policy definitions of “digital literacy” and actual teaching practice. We need to find workable definitions of digital literacy; obtain a better understanding of what digital literacy might look like in practice; and identify pedagogical approaches, which...... support teachers in designing digital literacy learning. We suggest that frameworks such as Problem Based Learning (PBL) are approaches that enable digital literacy learning because they provide good settings for engaging with digital literacy. We illustrate this through analysis of a case. Furthermore......, these operate on a meso-level mediating between high-level concepts of digital literacy and classroom practice....

  15. FPGA-Based Plant Protection System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yoon Hee; Ha, Jae Hong; Kim, Hang Bae [KEPCO E and C, Daejeon (Korea, Republic of)

    2011-08-15

    This paper relates to a plant protection system which detects non-permissible conditions and determines initiation of protective actions for nuclear power plants (NPPs). Conventional plant protection systems were designed based on analog technologies. It is well known that existing protection systems for NPPs contain many components which are becoming obsolete at an increasing rate. Nowadays maintenance and repair for analog-based plant protection systems may be difficult as analog parts become obsolete or difficult to obtain. Accordingly, as an alternative to the analog technology, the digitalisation of the plant protection system was required. Recently digital plant protection systems which include programmable logic controllers (PLCs) and/or computers have been introduced. However PLC or computer-based plant protection systems use an operating system and application software, and so they may result in a common mode failure when a problem occurs in the operating system or application software. Field Programmable Gate Arrays (FPGAs) are highlighted as an alternative to conventional protection or control systems. The paper presents the design of a four-channel plant protection system whose protection functions are implemented in FPGAs without any central processing unit or operating system.

  16. FPGA-Based Plant Protection System

    International Nuclear Information System (INIS)

    Lee, Yoon Hee; Ha, Jae Hong; Kim, Hang Bae

    2011-01-01

    This paper relates to a plant protection system which detects non-permissible conditions and determines initiation of protective actions for nuclear power plants (NPPs). Conventional plant protection systems were designed based on analog technologies. It is well known that existing protection systems for NPPs contain many components which are becoming obsolete at an increasing rate. Nowadays maintenance and repair for analog-based plant protection systems may be difficult as analog parts become obsolete or difficult to obtain. Accordingly, as an alternative to the analog technology, the digitalisation of the plant protection system was required. Recently digital plant protection systems which include programmable logic controllers (PLCs) and/or computers have been introduced. However PLC or computer-based plant protection systems use an operating system and application software, and so they may result in a common mode failure when a problem occurs in the operating system or application software. Field Programmable Gate Arrays (FPGAs) are highlighted as an alternative to conventional protection or control systems. The paper presents the design of a four-channel plant protection system whose protection functions are implemented in FPGAs without any central processing unit or operating system

  17. Digital Preservation in Open-Source Digital Library Software

    Science.gov (United States)

    Madalli, Devika P.; Barve, Sunita; Amin, Saiful

    2012-01-01

    Digital archives and digital library projects are being initiated all over the world for materials of different formats and domains. To organize, store, and retrieve digital content, many libraries as well as archiving centers are using either proprietary or open-source software. While it is accepted that print media can survive for centuries with…

  18. Digital Density as the Driving Force of Digital Transformation Processes

    OpenAIRE

    Bush, Xavier

    2016-01-01

    Digital technologies have increased the influence of technology in business, even changing business models and strategies of organisations. This influence, called Digital Transformation of Business (DT), happens when there is an increase of the number of digital connections, information and interactions. This phenom-ena has been defined as Digital Density (DD) and aims to provide an assessment of the digitalization status of an organization. With the concept of DD we pro-pose the DD Framework, t...

  19. Digital Tectonics

    DEFF Research Database (Denmark)

    Christiansen, Karl; Borup, Ruben; Søndergaard, Asbjørn

    2014-01-01

    Digital Tectonics treats the architectonical possibilities in digital generation of form and production. The publication is the first volume of a series, in which aspects of the strategic focus areas of the Aarhus School of Architecture will be disseminated.......Digital Tectonics treats the architectonical possibilities in digital generation of form and production. The publication is the first volume of a series, in which aspects of the strategic focus areas of the Aarhus School of Architecture will be disseminated....

  20. Digital Literacy Learning in Higher Education through Digital Storytelling Approach

    Science.gov (United States)

    Chan, Banny S. K.; Churchill, Daniel; Chiu, Thomas K. F.

    2017-01-01

    It is necessary to develop digital literacy skills with which students can communicate and express their ideas effectively using digital media. The educational sectors around the world are beginning to incorporate digital literacy into the curriculum. Digital storytelling, one of the possible classroom activities, is an approach which may help…

  1. Digital mammography

    International Nuclear Information System (INIS)

    Bick, Ulrich; Diekmann, Felix

    2010-01-01

    This state-of-the-art reference book provides in-depth coverage of all aspects of digital mammography, including detector technology, image processing, computer-aided diagnosis, soft-copy reading, digital workflow, and PACS. Specific advantages and disadvantages of digital mammography in comparison to screen-film mammography are thoroughly discussed. By including authors from both North America and Europe, the book is able to outline variations in the use, acceptance, and quality assurance of digital mammography between the different countries and screening programs. Advanced imaging techniques and future developments such as contrast mammography and digital breast tomosynthesis are also covered in detail. All of the chapters are written by internationally recognized experts and contain numerous high-quality illustrations. This book will be of great interest both to clinicians who already use or are transitioning to digital mammography and to basic scientists working in the field. (orig.)

  2. Cost Model for Digital Preservation: Cost of Digital Migration

    DEFF Research Database (Denmark)

    Kejser, Ulla Bøgvad; Nielsen, Anders Bo; Thirifays, Alex

    2011-01-01

    The Danish Ministry of Culture has funded a project to set up a model for costing preservation of digital materials held by national cultural heritage institutions. The overall objective of the project was to increase cost effectiveness of digital preservation activities and to provide a basis...... for comparing and estimating future cost requirements for digital preservation. In this study we describe an activity-based costing methodology for digital preservation based on the Open Archice Information System (OAIS) Reference Model. Within this framework, which we denote the Cost Model for Digital...... Preservation (CMDP), the focus is on costing the functional entity Preservation Planning from the OAIS and digital migration activities. In order to estimate these costs we have identified cost-critical activities by analysing the functions in the OAIS model and the flows between them. The analysis has been...

  3. Recent progress in SG level control in French PWR plants

    International Nuclear Information System (INIS)

    Parry, A.; Petetrot, J.F.; Vivier, M.J.

    1985-10-01

    Controlling the steam generator (SG) level is of major importance in a large PWR plant. This has led to extensive work on SG computer models. This paper presents results of the comparison between calculations and tests on the first four-loop plant in France. Four-loop plants started up after 1985 will be equipped with digital instead of analog controllers. A new SG level control has been designed and then optimised using the validated SG model. A prototype of this new system has been successfully tested on a three-loop plant. 4 refs

  4. Digital Tourism on the Way to Digital Marketing Success

    OpenAIRE

    RATIU, Monica Paula; PURCAREA, Ioan Matei

    2015-01-01

    There is a real need of digital support of the tourist experience before, during and after the tourist activity, because digitization is steadily becoming the main pathway for consumer journeys. The digital revolution changed the way consumers shop for travel products and interact with brands. Tourism businesses need to utilize digital marketing techniques in their practices and to right track consumer activity across channels and devices. Getting vital information from customers via social m...

  5. Image Harvest: an open-source platform for high-throughput plant image processing and analysis

    Science.gov (United States)

    Knecht, Avi C.; Campbell, Malachy T.; Caprez, Adam; Swanson, David R.; Walia, Harkamal

    2016-01-01

    High-throughput plant phenotyping is an effective approach to bridge the genotype-to-phenotype gap in crops. Phenomics experiments typically result in large-scale image datasets, which are not amenable for processing on desktop computers, thus creating a bottleneck in the image-analysis pipeline. Here, we present an open-source, flexible image-analysis framework, called Image Harvest (IH), for processing images originating from high-throughput plant phenotyping platforms. Image Harvest is developed to perform parallel processing on computing grids and provides an integrated feature for metadata extraction from large-scale file organization. Moreover, the integration of IH with the Open Science Grid provides academic researchers with the computational resources required for processing large image datasets at no cost. Image Harvest also offers functionalities to extract digital traits from images to interpret plant architecture-related characteristics. To demonstrate the applications of these digital traits, a rice (Oryza sativa) diversity panel was phenotyped and genome-wide association mapping was performed using digital traits that are used to describe different plant ideotypes. Three major quantitative trait loci were identified on rice chromosomes 4 and 6, which co-localize with quantitative trait loci known to regulate agronomically important traits in rice. Image Harvest is an open-source software for high-throughput image processing that requires a minimal learning curve for plant biologists to analyzephenomics datasets. PMID:27141917

  6. Digital Library and Digital Reference Service: Integration and Mutual Complementarity

    Science.gov (United States)

    Liu, Jia

    2008-01-01

    Both the digital library and the digital reference service were invented and have been developed under the networked environment. Among their intersections, the fundamental thing is their symbiotic interest--serving the user in a more efficient way. The article starts by discussing the digital library and its service and the digital reference…

  7. Digital Materialisms: Frameworks for Digital Media Studies

    OpenAIRE

    Casemajor, Nathalie

    2015-01-01

    Since the 1980s, digital materialism has received increasing interest in the field of media studies. Materialism as a theoretical paradigm assumes that all things in the world are tied to physical processes and matter. Yet within digital media studies, the understanding of what should be the core object of a materialist analysis is debated. This paper proposes to untangle some of the principal theoretical propositions that compose the field of digital materialism. It outlines six frameworks t...

  8. Design of wireless communication systems for nuclear power plant environments

    International Nuclear Information System (INIS)

    Kadri, A.

    2007-01-01

    The problem of low-SNR (Signal-to-Noise ratio) digital communication system design in man-made electromagnetic environment within a nuclear power plant is addressed. A canonical structure of the low-SNR receiver is derived and analyzed for its bit error rate performance. The parameters that affect the error rate performance are identified and illustrated. Several well-known digital modulations are considered. It is shown that the receiver structure is dependent on the first-order probability density function of the noise environment. Thus, we offer comments for its robust implementation and its effect on bit error rate performance. We model the EM environment within the nuclear power plant to be e - mixture model, the parameters of which can be estimated to fit the environment. (author)

  9. Identification of nonlinear dynamics in power plant components using neural networks

    International Nuclear Information System (INIS)

    Parlos, A.G.; Fernandez, B.; Tsai, W.K.

    1990-01-01

    Advances in digital computer technology have enabled widespread implementation of closed-loop digital control systems in a variety of industries. In some instances, however, the complexity of the plant and the uncertainty associated with the parameters involved in the mathematical modeling narrow the range of applicability of most systematic control system design methodologies. A multiyear project has been initiated to assess the feasibility of the artificial neural networks (ANNs) technology for computerized enhanced diagnostics and control of nuclear power plant components. At this stage of the project, a new methodology, based on backpropagation learning, has been developed for identifying the nonlinear dynamic systems from a set of input-output data known as the training set

  10. Digital Banking: Risks of Financial Digitalization

    Directory of Open Access Journals (Sweden)

    Kornіvska Valerіa O.

    2017-09-01

    Full Text Available The paper demonstrates the results of the research into development of the digital economy in the global financial space, shows the contradictions of these processes in the context of the growth of financial inclusion of households, identifies the risks of active introduction of digital banking in poor countries of the world. The characteristics of the processes of growth of the influence of banking institutions on the operational activity and daily life of households are given, and it is proved that under conditions of digital banking, without having any other alternative ways of economic activity in terms of money circulation than non-cash turnover, clients are forced to agree to unlimited presence of financial operators in social systems. It is substantiated that in Ukraine the global risk of digitalization of the society is gradually developing as a result of the creation of unified information systems for the control of global financial flows.

  11. Older people and digital disengagement: a fourth digital divide?

    Science.gov (United States)

    Olphert, Wendy; Damodaran, Leela

    2013-01-01

    Digital technologies are becoming more pervasive in all areas of society. Enabling everyone to have access and capability to use the Internet and associated digital technologies, summed up in the term 'digital inclusion', is seen to have wide-ranging benefits to the individual, to the economy and to society. For older people, being digitally included can help them to maintain their independence, social connectedness and sense of worth in the face of declining health or limited capabilities, as well as also offering new opportunities to improve their quality of life. At present however, access to the technology and to the benefits is not equally distributed either between or within nations, and older people tend to be on the 'wrong' side of what is termed the 'digital divide'. Governments globally are developing strategies to promote digital inclusion and indeed Internet uptake is increasing steadily, including amongst older people. However, such strategies have focussed on getting people online, and there appears to be an assumption that once someone is online they will remain 'digitally engaged'. In fact statistics show that some users give up using the Internet, and there is emerging evidence that older people are more vulnerable to the factors which can lead to this outcome. The authors see this phenomenon as a potential but largely unrecognised 'fourth digital divide' which has serious implications for social inclusion. The objectives of this article are (a) to raise awareness of the phenomenon of digital disengagement by considering some of the emerging evidence, (b) to explore some of the potential implications of not recognising and therefore not addressing the needs of the digitally disengaged older population, and (c) to reveal the prevailing gap in knowledge which future research should address. Copyright © 2013 S. Karger AG, Basel.

  12. Addressing selected problems of the modelling of digital control systems

    International Nuclear Information System (INIS)

    Sedlak, J.

    2004-12-01

    The introduction of digital systems to practical activities at nuclear power plants brings about new requirements for their modelling for the purposes of reliability analyses required for plant licensing as well as for inclusion into PSA studies and subsequent use in applications for the assessment of events, limits and conditions, and risk monitoring. It is very important to assess, both qualitatively and quantitatively, the effect of this change on operational safety. The report describes selected specific features of reliability analysis of digital system and recommends methodological procedures. The chapters of the report are as follows: (1) Flexibility and multifunctionality of the system. (2) General framework of reliability analyses (Understanding the system; Qualitative analysis; Quantitative analysis; Assessment of results, comparison against criteria; Documenting system reliability analyses; Asking for comments and their evaluation); and (3) Suitable reliability models (Reliability models of basic events; Monitored components with repair immediately following defect or failure; Periodically tested components; Constant unavailability (probability of failure to demand); Application of reliability models for electronic components; Example of failure rate decomposition; Example modified for diagnosis successfulness; Transfer of reliability analyses to PSA; Common cause failures - CCF; Software backup and CCF type failures, software versus hardware). (P.A.)

  13. Regulador cuadrático lineal y control predictivo aplicados en un sistema de cuatro tanques: una comparación de rendimiento

    Directory of Open Access Journals (Sweden)

    William Oswaldo Chamorro Hernández

    2018-03-01

    Full Text Available Este documento presenta una comparación entre dos técnicas lineales de controladores conocidos como PI-LOR y MPC con restricciones suaves aplicada a un proceso de cuatro tanques acoplados, cuyas características principales son las no linealidades, múltiples entradas y salidas y una dinámica lenta. El modelo es linealizado alrededor de un punto de funcionamiento utilizando un método de optimización, denominado mínimos cuadrados. Además, se presenta una formulación matemática general para ambos controladores que puede ser fácilmente extendida a cualquier control de procesos. Todo el procedimiento es descrito en detalle, así como los resultados de la simulación para ambos controladores. Para lograr una comparación real del rendimiento, los datos experimentales son obtenidos en las mismas condiciones y se analizaron todos los parámetros de respuesta.

  14. Reliability modeling of digital RPS with consideration of undetected software faults

    Energy Technology Data Exchange (ETDEWEB)

    Khalaquzzaman, M.; Lee, Seung Jun; Jung, Won Dea [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Man Cheol [Chung Ang Univ., Seoul (Korea, Republic of)

    2013-10-15

    This paper provides overview of different software reliability methodologies and proposes a technic for estimating the reliability of RPS with consideration of undetected software faults. Software reliability analysis of safety critical software has been challenging despite spending a huge effort for developing large number of software reliability models, and no consensus yet to attain on an appropriate modeling methodology. However, it is realized that the combined application of BBN based SDLC fault prediction method and random black-box testing of software would provide better ground for reliability estimation of safety critical software. Digitalizing the reactor protection system of nuclear power plant has been initiated several decades ago and now full digitalization has been adopted in the new generation of NPPs around the world because digital I and C systems have many better technical features like easier configurability and maintainability over analog I and C systems. Digital I and C systems are also drift-free and incorporation of new features is much easier. Rules and regulation for safe operation of NPPs are established and has been being practiced by the operators as well as regulators of NPPs to ensure safety. The failure mechanism of hardware and analog systems well understood and the risk analysis methods for these components and systems are well established. However, digitalization of I and C system in NPP introduces some crisis and uncertainty in reliability analysis methods of the digital systems/components because software failure mechanisms are still unclear.

  15. Sports Digitalization

    DEFF Research Database (Denmark)

    Xiao, Xiao; Hedman, Jonas; Tan, Felix Ter Chian

    2017-01-01

    evolution, as digital technologies are increasingly entrenched in a wide range of sporting activities and for applications beyond mere performance enhancement. Despite such trends, research on sports digitalization in the IS discipline is surprisingly still nascent. This paper aims at establishing...... a discourse on sports digitalization within the discipline. Toward this, we first provide an understanding of the institutional characteristics of the sports industry, establishing its theoretical importance and relevance in our discipline; second, we reveal the latest trends of digitalization in the sports...

  16. Digitized mammograms

    International Nuclear Information System (INIS)

    Bruneton, J.N.; Balu-Maestro, C.; Rogopoulos, A.; Chauvel, C.; Geoffray, A.

    1988-01-01

    Two observers conducted a blind evaluation of 100 mammography files, including 47 malignant cases. Films were read both before and after image digitization at 50 μm and 100 μm with the FilmDRSII. Digitization permitted better analysis of the normal anatomic structures and moderately improved diagnostic sensitivity. Searches for microcalcifications before and after digitization at 100 μm and 50 μm showed better analysis of anatomic structures after digitization (especially for solitary microcalcifications). The diagnostic benefit, with discovery of clustered microcalcifications, was more limited (one case at 100 μm, nine cases at 50 μm). Recognition of microcalcifications was clearly improved in dense breasts, which can benefit from reinterpretation after digitization at 50 μm rather 100μm

  17. Digital radiography

    International Nuclear Information System (INIS)

    Coulomb, M.; Dal Soglio, S.; Pittet-Barbier, L.; Ranchoup, Y.; Thony, F.; Ferretti, G.; Robert, F.

    1992-01-01

    Digital projection radiography may replace conventional radiography some day, provided it can meet several requirements: equal or better diagnostic effectiveness of the screen-film systems; reasonable image cost; real improvement in the productivity of the Departments of Imaging. All digital radiographic systems include an X-ray source, an image acquisition and formatting sub-system, a display and manipulation sub-system, and archiving subsystem and a laser editing system, preferably shared by other sources of digital images. Three digitization processes are available: digitization of the radiographic film, digital fluorography and phospholuminescent detectors with memory. The advantages of digital fluoroscopy are appealing: real-time image acquisition, suppression of cassettes; but its disadvantages are far from negligible: it cannot be applied to bedside radiography, the field of examination is limited, and the wide-field spatial resolution is poor. Phospholuminescent detectors with memory have great advantages: they can be used for bedside radiographs and on all the common radiographic systems; spatial resolution is satisfactory; its current disadvantages are considerable. These two systems, have common properties making up the entire philosophy of digital radiology and specific features that must guide our choice according to the application. Digital fluorography is best applied in pediatric radiology. However, evaluation works have showed that it was applicable with sufficient quality to many indications of general radiology in which a fluoroscopic control and fast acquisition of the images are essential; the time gained on the examination may be considerable, as well as the savings on film. Detectors with memory are required for bedside radiographs, in osteoarticular and thoracic radiology, in all cases of traumatic emergency and in the resuscitation and intensive care departments

  18. Reliability modeling of digital component in plant protection system with various fault-tolerant techniques

    International Nuclear Information System (INIS)

    Kim, Bo Gyung; Kang, Hyun Gook; Kim, Hee Eun; Lee, Seung Jun; Seong, Poong Hyun

    2013-01-01

    Highlights: • Integrated fault coverage is introduced for reflecting characteristics of fault-tolerant techniques in the reliability model of digital protection system in NPPs. • The integrated fault coverage considers the process of fault-tolerant techniques from detection to fail-safe generation process. • With integrated fault coverage, the unavailability of repairable component of DPS can be estimated. • The new developed reliability model can reveal the effects of fault-tolerant techniques explicitly for risk analysis. • The reliability model makes it possible to confirm changes of unavailability according to variation of diverse factors. - Abstract: With the improvement of digital technologies, digital protection system (DPS) has more multiple sophisticated fault-tolerant techniques (FTTs), in order to increase fault detection and to help the system safely perform the required functions in spite of the possible presence of faults. Fault detection coverage is vital factor of FTT in reliability. However, the fault detection coverage is insufficient to reflect the effects of various FTTs in reliability model. To reflect characteristics of FTTs in the reliability model, integrated fault coverage is introduced. The integrated fault coverage considers the process of FTT from detection to fail-safe generation process. A model has been developed to estimate the unavailability of repairable component of DPS using the integrated fault coverage. The new developed model can quantify unavailability according to a diversity of conditions. Sensitivity studies are performed to ascertain important variables which affect the integrated fault coverage and unavailability

  19. Cyber secure systems approach for NPP digital control systems

    Energy Technology Data Exchange (ETDEWEB)

    McCreary, T. J.; Hsu, A. [HF Controls Corporation, 16650 Westgrove Drive, Addison, TX 75001 (United States)

    2006-07-01

    Whether fossil or nuclear power, the chief operations goal is to generate electricity. The heart of most plant operations is the I and C system. With the march towards open architecture, the I and C system is more vulnerable than ever to system security attacks (denial of service, virus attacks and others), thus jeopardizing plant operations. Plant staff must spend large amounts of time and money setting up and monitoring a variety of security strategies to counter the threats and actual attacks to the system. This time and money is a drain on the financial performance of a plant and distracts valuable operations resources from their real goals: product. The pendulum towards complete open architecture may have swung too far. Not all aspects of proprietary hardware and software are necessarily 'bad'. As the aging U.S. fleet of nuclear power plants starts to engage in replacing legacy control systems, and given the on-going (and legitimate) concern about the security of present digital control systems, decisions about how best to approach cyber security are vital to the specification and selection of control system vendors for these upgrades. The authors maintain that utilizing certain resources available in today's digital technology, plant control systems can be configured from the onset to be inherently safe, so that plant staff can concentrate on the operational issues of the plant. The authors postulate the concept of the plant I and C being bounded in a 'Cyber Security Zone' and present a design approach that can alleviate the concern and cost at the plant level of dealing with system security strategies. Present approaches through various IT cyber strategies, commercial software, and even postulated standards from various industry/trade organizations are almost entirely reactive and simply add to cost and complexity. This Cyber Security Zone design demonstrates protection from the four classes of cyber security attacks: 1)Threat from

  20. Cyber secure systems approach for NPP digital control systems

    International Nuclear Information System (INIS)

    McCreary, T. J.; Hsu, A.

    2006-01-01

    Whether fossil or nuclear power, the chief operations goal is to generate electricity. The heart of most plant operations is the I and C system. With the march towards open architecture, the I and C system is more vulnerable than ever to system security attacks (denial of service, virus attacks and others), thus jeopardizing plant operations. Plant staff must spend large amounts of time and money setting up and monitoring a variety of security strategies to counter the threats and actual attacks to the system. This time and money is a drain on the financial performance of a plant and distracts valuable operations resources from their real goals: product. The pendulum towards complete open architecture may have swung too far. Not all aspects of proprietary hardware and software are necessarily 'bad'. As the aging U.S. fleet of nuclear power plants starts to engage in replacing legacy control systems, and given the on-going (and legitimate) concern about the security of present digital control systems, decisions about how best to approach cyber security are vital to the specification and selection of control system vendors for these upgrades. The authors maintain that utilizing certain resources available in today's digital technology, plant control systems can be configured from the onset to be inherently safe, so that plant staff can concentrate on the operational issues of the plant. The authors postulate the concept of the plant I and C being bounded in a 'Cyber Security Zone' and present a design approach that can alleviate the concern and cost at the plant level of dealing with system security strategies. Present approaches through various IT cyber strategies, commercial software, and even postulated standards from various industry/trade organizations are almost entirely reactive and simply add to cost and complexity. This Cyber Security Zone design demonstrates protection from the four classes of cyber security attacks: 1)Threat from an intruder attempting to