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Sample records for plant control ajustable

  1. 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.

  2. Cronograma de amostragem de alface cultivada em hidroponia para ajuste de curvas de crescimento vegetativo Sampling chronology of hydroponics lettuce plants for adjusting vegetative growth curves

    Directory of Open Access Journals (Sweden)

    Sidinei José Lopes

    2007-10-01

    Full Text Available O objetivo deste trabalho foi determinar o cronograma de amostragem de plantas de alface hidropônica, para ajuste de curvas de crescimento durante o período vegetativo. Foram realizados dois cultivos de alface, variedade Regina, de 8/9/2004 a 19/11/2004 (primavera/verão e 22/2/2005 a 24/5/2005 (verão/outono, em estufas de plástico do Dep. de Fitotecnia, da UFSM, Santa Maria, RS. A partir do ajuste do modelo co-seno com amostragem diária, registrada como padrão, diferentes intervalos entre as amostragens foram simulados para o ajuste do mesmo modelo. A fim de se encontrar o intervalo adequado, foi comparada a variância de falta de ajuste do modelo de amostragem diária com as variâncias de falta de ajuste dos modelos com diferentes intervalos de amostragens pelo teste F. Os cronogramas de amostragens para ajuste de curvas de crescimento de plantas de alface sob hidroponia, para experimentos de primavera/verão e verão/outono, possuem intervalos iguais a dois dias, para fitomassa seca total da planta e da folha; intervalos de quatro dias, para fitomassa de raiz; e, diariamente, para área foliar.The objective of this work was to determinate a sampling chronology to adjust lettuce hidroponic growth curves during its vegetative development. The variety Regina was grown from September 8, 2004 until November 19, 2004 (spring/summer and February 22, 2005 until May 24, 2005 (summer/fall. Plants were placed inside a plastic covered greenhouse in Santa Maria, RS, Brazil. Based on the adjusted cosine model, daily samples were taken as standard and different sampling intervals were simulated in order to better adjust the same model. To estimate de adequate sampling interval a comparison was conducted between the variance of lack of adjustment of the daily sampling with the variance of lack of adjustment of different samplings intervals using an F test. Sampling chronograms for adjusting crop growth curves of hydroponics lettuce plants for both

  3. Efecto en la respuesta temporal del parámetro ajustable del control adaptativo con modelo de referencia de primer orden

    OpenAIRE

    Vargas Tamani, Bruno; Universidad Nacional Mayor de San Marcos

    2014-01-01

    Se presentan los resultados experimentales del control adaptativo con modelo de referencia, de una planta que de acuerdo a su identificación previamente realizada se puede representar como un sistema de primer orden. Se elige como modelo de referencia también uno de primer orden con ganancia unitaria. Se realiza el análisis del controlador adaptativo, justificándose que su desempeño en lazo cerrado dependerá de la elección adecuada de un parámetro escalar ajustable. Se implementa el controlad...

  4. Ajuste escolar, rechazo y violencia en adolescentes.

    OpenAIRE

    Martínez Ferrer, Belén

    2009-01-01

    RESUMEN El objetivo general de esta tesis doctoral es analizar las relaciones existentes entre el contexto familiar, el escolar y la autoestima, en la predicción de tres indicadores de ajuste adolescente (ajuste escolar, rechazo escolar entre iguales y violencia/victimización escolar). Las variables consideradas en la investigación son: 1. Variables escolares: violencia escolar, victimización, rechazo entre iguales, actitud hacia la autoridad, actitud hacia la transgresión, actitud haci...

  5. Controladores auto-ajustables para una clase de sistemas bilineales

    Directory of Open Access Journals (Sweden)

    Anna Patete

    2011-06-01

    Full Text Available En este trabajo, se propone un algoritmo auto-ajustable implícito basado en el criterio de varianza mínima generalizada para la estabilización de una clase de sistemas bilineales. La estabilidad del algoritmo propuesto es demostrada usando una función de Lyapunov y la estrategia de control por superficie deslizante. El algoritmo auto-ajustable propuesto es aplicado a una planta piloto térmica para evaluar su desempeño. / In this paper, a self-tuning algorithm based on the generalized minimum variance criterion is proposed for the stabilization of a class of bilinear systems. Using a Lyapunov function and the sliding mode control approach, the stability of the proposed algorithm is proven. The proposed self-tuning algorithm is applied to a simulated example to evaluate its performance.

  6. Aquatic plant control research

    Energy Technology Data Exchange (ETDEWEB)

    Pryfogle, P.A.; Rinehart, B.N. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Ghio, E.G. [Pacific Gas & Electric Company, San Francisco, CA (United States). Hydro Generation Engineering

    1997-05-01

    The Northwest region of the United States contains extensive canal systems that transport water for hydropower generation. Nuisance plants, including algae, that grow in these systems reduce their hydraulic capacity through water displacement and increased surface friction. Most control methods are applied in an ad hoc fashion. The goal of this work is to develop cost-effective, environmentally sound, long-term management strategies to prevent and control nuisance algal growth. This paper reports on a multi-year study, performed in collaboration with the Pacific Gas & Electric Company, to investigate algal growth in their canal systems, and to evaluate various control methodologies. Three types of controls, including mechanical, biological and chemical treatment, were selected for testing and evaluation. As part of this study, water quality data were collected and algal communities were sampled from numerous stations throughout the distribution system at regular intervals. This study resulted in a more comprehensive understanding of conditions leading to the development of nuisance algal growth, a better informed selection of treatment plans, and improved evaluation of the effectiveness for the control strategies selected for testing.

  7. Aquatic Plants and their Control.

    Science.gov (United States)

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  8. [Alfalfa Planting as weed control

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a letter to farming cooperators regarding the stipulations surrounding alfalfa plantings in lieu of small grain plantings to provide weed control,...

  9. [Quality control of plant extract].

    Science.gov (United States)

    Shao, Yun-dong; Gao, Wen-yuan; Liu, Dan; Jia, Wei; Duan, Hong-Quan; Zhang, Tie-jun

    2003-10-01

    The current situation of plant extract in domestic and international market was analyzed in the paper. The quality control of 20 plant extracts which have reasonably good sales in USA market was compared and analyzed. The analysis of the quality control of six plant extracts indicated that there were two main reasons leading to the varied quality specifications among different suppliers. One reason was that the plant species utilized by different companies were different. The other reason was that the extraction processes were different among different production plants. Comparing with the significant international suppliers of plant extracts, the product quality of Chinese companies were not satisfactory. It was suggested that chromatography and chromatographic fingerprint techniques should be applied to improve the quality control standard of plant extract in our country.

  10. Chemical Control of Plant Growth.

    Science.gov (United States)

    Agricultural Research Center (USDA), Beltsville, MD.

    Seven experiments are presented in this Science Study Aid to help students investigate the control of plant growth with chemicals. Plant growth regulators, weed control, and chemical pruning are the topics studied in the experiments which are based on investigations that have been and are being conducted at the U. S. Agricultural Research Center,…

  11. Silicon in plant disease control

    Directory of Open Access Journals (Sweden)

    Edson Ampélio Pozza

    2015-06-01

    Full Text Available All essential nutrients can affect the incidence and severity of plant diseases. Although silicon (Si is not considered as an essential nutrient for plants, it stands out for its potential to decrease disease intensity in many crops. The mechanism of Si action in plant resistance is still unclear. Si deposition in plant cell walls raised the hypothesis of a possible physical barrier to pathogen penetration. However, the increased activity of phenolic compounds, polyphenol oxidases and peroxidases in plants treated with Si demonstrates the involvement of this element in the induction of plant defense responses. The studies examined in this review address the role of Si in disease control and the possible mechanisms involved in the mode of Si action in disease resistance in plants.

  12. INSTRUMENTATION CONTROLLING INDUSTRIAL PLANT

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    Chuvashlova Marina Vladimirovna

    2013-01-01

    Full Text Available The purpose of this study is to analyze theoretical and practical basis of controlling and to provide implementation guidelines for enterprise controlling. The problem of controlling implementation was considered by two criteria: sphere of application and time of validity. Taking into account sphere of application criterion the objectives can be achieved by certain tools, namely: management accounting in the form of profit and loss statement; information flow in the form of workflow system and mapping of business processes; planning which includes budgeting and monitoring that could in turn allow to compare performance to predetermined standards, plans or objectives; responsibility accounting. The second criterion that is time of validity is considered as strategic.

  13. INSTRUMENTATION CONTROLLING INDUSTRIAL PLANT

    Directory of Open Access Journals (Sweden)

    Марина Владимировна Чувашлова

    2013-04-01

    Full Text Available The purpose of this study is to analyze theoretical and practical basis of controlling and to provide implementation guidelines for enterprise controlling. The problem of controlling implementation was considered by two criteria: sphere of application and time of validity.Taking into account sphere of application criterion the objectives can be achieved by certain tools, namely: management accounting in the form of profit and loss statement; information flow in the form of workflow system and mapping of business processes; planning which includes budgeting and monitoring that could in turn allow to compare performance to predetermined standards, plans or objectives; responsibility accounting.The second criterion that is time of validity is considered as strategic.DOI: http://dx.doi.org/10.12731/2218-7405-2013-1-39

  14. Process control in biogas plants

    DEFF Research Database (Denmark)

    Holm-Nielsen, Jens Bo; Oleskowicz-Popiel, Piotr

    2013-01-01

    Efficient monitoring and control of anaerobic digestion (AD) processes are necessary in order to enhance biogas plant performance. The aim of monitoring and controlling the biological processes is to stabilise and optimise the production of biogas. The principles of process analytical technology...

  15. Estilos relacionales parentales y ajuste adolescente

    OpenAIRE

    Oliva Delgado, Alfredo; Parra Jiménez, Agueda; Arranz Freijo, Enrique

    2008-01-01

    En este artículo se presentan los resultados de un estudio realizado sobre una muestra de 848 adolescentes de edades comprendidas entre los 12 y los 17 años, que cumplimentaron un cuestionario que incluía una escala con 6 dimensiones sobre su percepción del estilo parental o relacional materno y paterno y otros instrumentos para evaluar el ajuste adolescente. La realización de un análisis de conglomerados a partir de las puntuaciones en las 6 dimensiones que componían la escala re...

  16. Estilos relacionales parentales y ajuste adolescente

    OpenAIRE

    Oliva Delgado, Alfredo; Parra Jiménez, Agueda; Arranz Freijo, Enrique

    2008-01-01

    En este artículo se presentan los resultados de un estudio realizado sobre una muestra de 848 adolescentes de edades comprendidas entre los 12 y los 17 años, que cumplimentaron un cuestionario que incluía una escala con 6 dimensiones sobre su percepción del estilo parental o relacional materno y paterno y otros instrumentos para evaluar el ajuste adolescente. La realización de un análisis de conglomerados a partir de las puntuaciones en las 6 dimensiones que componían la escala re...

  17. El ajuste: origen de la crisis europea

    Directory of Open Access Journals (Sweden)

    Andrés Musacchio

    2013-01-01

    Full Text Available El objetivo del trabajo es analizar el impacto de las transformaciones institucionales en la Unión Europea desde los años ochenta, sobre las políticas de ajuste de los Estados nacionales ante shocks externos o problemas internos. La pérdida de instrumentos de política económica centró los ajustes en el mercado laboral y la seguridad social, impulsando una distribución regresiva del ingreso, el desmantelamiento parcial de los estados de bienestar y la precarización del empleo. Las tendencias se refuerzan con la necesidad de retener o captar inversiones en un contexto de fuerte competencia por su localización, que impulsa políticas "amigables" al capital, comprometiendo estándares laborales y de distribución del ingreso. Estas cuestiones tienen gran incidencia en la combinación de endeudamiento con estancamiento que se encuentran en la base de la crisis actual.

  18. Modelling and controlling hydropower plants

    CERN Document Server

    Munoz-Hernandez, German Ardul; Jones, Dewi Ieuan

    2013-01-01

    Hydroelectric power stations are a major source of electricity around the world; understanding their dynamics is crucial to achieving good performance.  Modelling and Controlling Hydropower Plants discusses practical and well-documented cases of modelling and controlling hydropower station modelling and control, focussing on a pumped storage scheme based in Dinorwig, North Wales.  Single-input-single-output and multiple-input-multiple-output models, which cover the linear and nonlinear characteristics of pump-storage hydroelectric power stations, are reviewed. The most important dynamic features are discussed, and the verification of these models by hardware in the loop simulation is described. To show how the performance of a pump-storage hydroelectric power station can be improved, classical and modern controllers are applied to simulated models of the Dinorwig power plant. These include PID, fuzzy approximation, feed-forward and model-based predictive control with linear and hybrid prediction models. Mod...

  19. AJUSTE DE MODELOS DE ELEMENTOS FINITOS

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    WILLIAM VÉLEZ

    2009-01-01

    Full Text Available El método del elemento finito es utilizado en todo el mundo como herramienta para analizar el comportamiento dinámico de sistemas estructurales. Sin embargo, se sabe que las predicciones efectuadas con el uso de modelos construidos empleando dicho método difieren de los resultados experimentales obtenidos a partir de ensayos de vibración en estructuras existentes. El área conocida en lengua inglesa como Model Updating, o Ajuste de Modelos, como se denomina en este documento, surgió como respuesta a dicha problemáticay apunta a efectuar correcciones paramétricas en los modelos de elementos finitos con el fin de lograr que las propiedades dinámicas analíticas se asemejen a sus contrapartes experimentales. El avance de esta disciplina durante los últimos veinte años ha sido vertiginoso; sin embargo, en el medio latinoamericano, y en particular en el colombiano, existe una difusión pobre de dicha temática. Este artículo presenta una revisión del estado del arte a la fecha de su publicación. Se espera que el presente trabajo motive la investigación en el campo del Ajuste de Modelos en centros diferentes a aquellos donde se ha concentrado hasta ahora el desarrollo de esta área y que a su vez provea información suficiente para que el sector industrial latinoamericano incluya dicha tecnología en sus prácticas.

  20. Ajuste estructural e informalidad en Guatemala

    Directory of Open Access Journals (Sweden)

    María José Paz Antolín

    2008-01-01

    Full Text Available Debido a la relevancia de las reformas económicas aplicadas para el desempeño económico de las últimas dos décadas son necesarios estudios que analicen estos vínculos. Éste es el objetivo del presente trabajo que se centra en la economía guatemalteca y en la evolución de sus condiciones laborales. El análisis tiene presente los rasgos comunes de las políticas de reforma llevadas a cabo pero se centra en lo distintivo del caso guatemalteco. En este sentido, destacan el contexto político y social y la particular forma de inserción en la economía mundial. Los distintos indicadores estudiados muestran cómo se ha producido un deterioro de las condiciones laborales, sobre todo por el crecimiento de la informalidad. Aunque éste ha sido un fenómeno típico en Guatemala su evolución presenta elementos novedosos vinculados precisamente con las políticas de ajuste.

  1. Advanced Coordinating Control System for Power Plant

    Institute of Scientific and Technical Information of China (English)

    WU Peng; WEI Shuangying

    2006-01-01

    The coordinating control system is popular used in power plant. This paper describes the advanced coordinating control by control methods and optimal operation, introduces their principals and features by using the examples of power plant operation. It is wealthy for automation application in optimal power plant operation.

  2. Efectos del tipo funcional de entrenamiento sobre el ajuste lector

    OpenAIRE

    Rosalinda Arroyo Hernández; Guadalupe Mares Cárdenas

    2009-01-01

    El presente trabajo tuvo por objetivo evaluar los efectos de entrenar cinco tipos de contacto con las relaciones entre objetos y sus elaboraciones lingüísticas sobre el ajuste lector de estudiantes universitarios. Primeramente los participantes fueron expuestos a una evaluación de ajuste lector, consistente en preguntas de diferente complejidad funcional, para posteriormente ser asignados aleatoriamente a uno de cinco grupos experimentales diferenciados por el nivel de complejidad funcional d...

  3. Idiomatic Control used in Sugar Plants

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Mølgaard; Nielsen, Jens Frederik Dalsgaard; Pedersen, Tom Søndergaard

    1993-01-01

    A description of a control system for a large scale industrial plant - the evaporator section of a sugar plant. The control system is based on the idiomatic control concept, causing decomposition into loop control units - idioms. Dynamic decoupling, feedforward- and feedback loops eg. have been...

  4. Idiomatic Control used in Sugar Plants

    DEFF Research Database (Denmark)

    Nielsen, Kirsten Mølgaard; Nielsen, Jens Frederik Dalsgaard; Pedersen, Tom Søndergaard

    1993-01-01

    A description of a control system for a large scale industrial plant - the evaporator section of a sugar plant. The control system is based on the idiomatic control concept, causing decomposition into loop control units - idioms. Dynamic decoupling, feedforward- and feedback loops eg. have been...

  5. Impacto da erva-moira na produção do tomateiro e ajuste de modelos matemáticos Impact of black nightshade on tomato plant production and mathematical model fitness

    Directory of Open Access Journals (Sweden)

    J.M Portugal

    2009-12-01

    Full Text Available Modelos matemáticos são úteis para estimar o impacto das infestantes nas culturas. Os objetivos deste trabalho foram: elucidar a interação de Solanum nigrum (ervamoira ou maria-pretinha com o tomateiro no sistema de sementeira direta e transplantado; e avaliar o impacto de diferentes densidades de infestação e períodos de tempo de competição na quantidade de frutos do tomateiro. Entre os anos 1991 e 2001, foram conduzidos cinco experimentos em campo na região tomaticultora de Portugal. Os experimentos seguiram o método aditivo, mantendo-se constante a densidade da cultura, enquanto o número de ervas-moiras variou entre 0 e 6 plantas m-2. Outro fator avaliado foi o período de convivência da infestante na cultura, incluindo os períodos do transplante/semeadura e o início da floração até a colheita. Os resultados de perda de produção foram ajustados aos modelos linear e hiperbólico. O comportamento das perdas de produção nas densidades mais baixas de erva-moira é do tipo linear. A erva-moira é uma espécie muito competitiva em relação ao tomateiro tanto quando a cultura é semeada quanto quando é transplantada. As perdas de produção foram maiores quando a cultura foi semeada, em comparação com a transplantada.Mathematical models are useful for estimating the impact of weeds on crops. The objectives of this study were to elucidate the interaction of Solanum nigrum (black nightshade with tomato plants in direct and transplanted sowing and to evaluate the impact of different infestation densities and competition time periods on tomato plant production. Between 1991 and 2001, five field experiments were conducted in the tomato growing region of Portugal using the additive method, keeping crop density constant, while changing the number of weeds from 0 and 6 plants m-2. The weed and crop coexistence period was also evaluated, from transplantation/sowing to the beginning of flowering or until harvest. The tomato yield

  6. Plant actin controls membrane permeability.

    Science.gov (United States)

    Hohenberger, Petra; Eing, Christian; Straessner, Ralf; Durst, Steffen; Frey, Wolfgang; Nick, Peter

    2011-09-01

    The biological effects of electric pulses with low rise time, high field strength, and durations in the nanosecond range (nsPEFs) have attracted considerable biotechnological and medical interest. However, the cellular mechanisms causing membrane permeabilization by nanosecond pulsed electric fields are still far from being understood. We investigated the role of actin filaments for membrane permeability in plant cells using cell lines where different degrees of actin bundling had been introduced by genetic engineering. We demonstrate that stabilization of actin increases the stability of the plasma membrane against electric permeabilization recorded by penetration of Trypan Blue into the cytoplasm. By use of a cell line expressing the actin bundling WLIM domain under control of an inducible promotor we can activate membrane stabilization by the glucocorticoid analog dexamethasone. By total internal reflection fluorescence microscopy we can visualize a subset of the cytoskeleton that is directly adjacent to the plasma membrane. We conclude that this submembrane cytoskeleton stabilizes the plasma membrane against permeabilization through electric pulses. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Model-Based Power Plant Master Control

    Energy Technology Data Exchange (ETDEWEB)

    Boman, Katarina; Thomas, Jean; Funkquist, Jonas

    2010-08-15

    The main goal of the project has been to evaluate the potential of a coordinated master control for a solid fuel power plant in terms of tracking capability, stability and robustness. The control strategy has been model-based predictive control (MPC) and the plant used in the case study has been the Vattenfall power plant Idbaecken in Nykoeping. A dynamic plant model based on nonlinear physical models was used to imitate the true plant in MATLAB/SIMULINK simulations. The basis for this model was already developed in previous Vattenfall internal projects, along with a simulation model of the existing control implementation with traditional PID controllers. The existing PID control is used as a reference performance, and it has been thoroughly studied and tuned in these previous Vattenfall internal projects. A turbine model was developed with characteristics based on the results of steady-state simulations of the plant using the software EBSILON. Using the derived model as a representative for the actual process, an MPC control strategy was developed using linearization and gain-scheduling. The control signal constraints (rate of change) and constraints on outputs were implemented to comply with plant constraints. After tuning the MPC control parameters, a number of simulation scenarios were performed to compare the MPC strategy with the existing PID control structure. The simulation scenarios also included cases highlighting the robustness properties of the MPC strategy. From the study, the main conclusions are: - The proposed Master MPC controller shows excellent set-point tracking performance even though the plant has strong interactions and non-linearity, and the controls and their rate of change are bounded. - The proposed Master MPC controller is robust, stable in the presence of disturbances and parameter variations. Even though the current study only considered a very small number of the possible disturbances and modelling errors, the considered cases are

  8. LA POLÍTICA SOCIAL EN TIEMPOS DE AJUSTE

    Directory of Open Access Journals (Sweden)

    Leonardo Garnier Rímolo

    2011-09-01

    Full Text Available La política social está nuevamente de moda. Hace unos años, eran la estabilización y el ajuste los temas que dominaban la literatura, los debates y hasta las conversaciones de los economistas. Hoy, es cada vez más frecuente la referencia a la pobreza, el costo social del ajuste, el rostro humano de la política económica, el gasto social, la salud, la educación, en fin, todos aquellos temas relativos a la calidad de vida y el desarrollo humano. A diferencia del pasado, sin embargo, este redescubrimiento de los objetivos sociales del desarrollo no olvida, sino que parte precisamente del reconocimiento de las limitaciones materiales y financieras que enfrentan las sociedades menos desarrolladas. La discusión actual busca redefinir el sentido de la política social en los tiempos del ajuste o, si se quiere, redefinir los procesos de ajuste a la luz de su verdadero objetivo: el desarrollo social.

  9. Novel Micro-organisms controlling plant pathogens

    OpenAIRE

    Köhl, J

    2009-01-01

    The invention relates to control of pathogen caused diseases on leaves, fruits and ears in plants, such as apple scab (Venturia inaequalis by treatment of plant with an isolate of Cladosporium cladosporioides. The treatment is effective in both prevention and treatment of the fungal infection

  10. Control of Fish and Aquatic Plants.

    Science.gov (United States)

    Hesser, R. B.; And Others

    This agriculture extension service publication from Pennsylvania State University is a handbook for the water body manager. The bulk of the contents deals with aquatic plant control. The different types of aquatic plants, their reproduction and growth, and their role in the ecology of the water body are introduced in this main section. Also, the…

  11. The use of simulators for the training of the NPP licensed personnel; El uso de los simuladores de adiestramiento como apoyo para el ajuste de sistemas de instrumentacion y control

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, F.; Ruiz, J. A.

    2005-07-01

    The full scope simulators used for the training of the NPP licensed personnel, are characterised by the integration of models of all the systems of the plant, so that a real time integrated response with a high degree of physical and functional fidelity may be provided. Due to these features, these simulators have showed high capabilities in the engineering field where they can support with effectiveness the design and tuning of I and C plant modifications. (Author)

  12. Plant Modeling for Human Supervisory Control

    DEFF Research Database (Denmark)

    Lind, Morten

    1999-01-01

    This paper provides an overview of multilevel flow modelling (MFM) and its application for design of displays for the supervisory control of industrial plant. The problem of designing the inforrrzatian content of sacpervisory displays is discussed and plant representations like MFM using levels...... is also provided by an analysis of the relations between levels of abstraction. It is also described how MFM supparts reazsonin about control actions by defining levels of intervention and by modal distinctions between function enablement and initiation....

  13. Shrub control by browsing: Targeting adult plants

    Science.gov (United States)

    da Silveira Pontes, Laíse; Magda, Danièle; Gleizes, Benoît; Agreil, Cyril

    2016-01-01

    Reconciling the well known benefits of shrubs for forage with environmental goals, whilst preventing their dominance, is a major challenge in rangeland management. Browsing may be an economical solution for shrubby rangelands as herbivore browsing has been shown to control juvenile shrub growth. Less convincing results have been obtained for adult plants, and long-term experiments are required to investigate the cumulative effects on adult plants. We therefore assessed the impact of different levels of browsing intensity on key demographic parameters for a major dominant shrub species (broom, Cytisus scoparius), focusing on adult plants. We assigned individual broom plants to one of three age classes: 3-5 years (young adults); 5-7 years (adults); and 7-9 years (mature adults). These plants were then left untouched or had 50% or 90% of their total edible stem biomass removed in simulated low-intensity and high-intensity browsing treatments, respectively. Morphological, survival and fecundity data were collected over a period of four years. Browsing affected the morphology of individual plants, promoting changes in subsequent regrowth, and decreasing seed production. The heavily browsed plants were 17% shorter, 32% narrower, and their twigs were 28% shorter. Light browsing seemed to control the growth of young adult plants more effectively than that of older plants. Reproductive output was considerably lower than for control plants after light browsing, and almost 100% lower after heavy browsing. High-intensity browsing had a major effect on survival causing high levels of plant mortality. We conclude that suitable browsing practices could be used to modify adult shrub demography in the management of shrub dominance and forage value.

  14. ITER prototype fast plant system controller

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, B., E-mail: bruno@ipfn.ist.utl.pt [Instituto de Plasmas e Fusao Nuclear - Laboratorio Associado, Instituto Superior Tecnico, P-1049-001 Lisboa (Portugal); Sousa, J.; Carvalho, B.B.; Rodrigues, A.P.; Correia, M.; Batista, A. [Instituto de Plasmas e Fusao Nuclear - Laboratorio Associado, Instituto Superior Tecnico, P-1049-001 Lisboa (Portugal); Vega, J. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Av. Complutense, Madrid (Spain); Ruiz, M.; Lopez, J.M. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Universidad Politecnica de Madrid (Spain); Castro, R. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Av. Complutense, Madrid (Spain); Wallander, A.; Utzel, N.; Makijarvi, P.; Simrock, S. [ITER Organization, CS 90 046, 13067 St. Paul lez Durance Cedex (France); Neto, A.; Alves, D.; Valcarcel, D.F. [Instituto de Plasmas e Fusao Nuclear - Laboratorio Associado, Instituto Superior Tecnico, P-1049-001 Lisboa (Portugal); Lousa, P.; Piedade, F.; Fernandes, L. [INOV, Lisbon (Portugal)

    2011-10-15

    ITER CODAC Design identified the need for slow and fast control plant systems, based respectively on industrial automation technology with maximum sampling rates below 100 Hz, and on embedded technology with higher sampling rates and more stringent real-time requirements. The fast system is applicable to diagnostics and plant systems in closed-control loops whose cycle times are below 1 ms. Fast controllers will be dedicated industrial controllers with the ability to supervise other fast and/or slow controllers, interface to actuators and sensors and high performance networks (HPN). This contribution presents the engineering design of two prototypes of a fast plant system controller (FPSC), specialized for data acquisition, constrained by ITER technological choices. This prototyping activity contributes to the Plant Control Design Handbook (PCDH) effort of standardization, specifically regarding fast controller characteristics. The prototypes will be built using two different form factors, PXIe and ATCA, with the aim of comparing the implementations. The presented solution took into consideration channel density, synchronization, resolution, sampling rates and the needs for signal conditioning such as filtering and galvanic isolation. The integration of the two controllers in the standard CODAC environment is also presented and discussed. Both controllers contain an EPICS IOC providing the interface to the mini-CODAC which will be used for all testing activities. The alpha version of the FPSC is also presented.

  15. Ajustes Conversacionales para el Aprendizaje de Contenidos en L2

    Directory of Open Access Journals (Sweden)

    Berta de Dios

    2010-07-01

    Full Text Available Este trabajo pretende describir las interacciones conversacionales entre el alumnado en las aulas AICLE. Nos preguntamos si hay un vínculo entre las características de las interacciones y el aprendizaje de contenidos no lingüísticos y, si es así, qué tipo de ajustes fomentan dicho aprendizaje. Las aulas AICLE son los entornos ideales para estudiar el vínculo entre ajustes conversacionales y aprendizaje de contenidos porque, al no ser en la lengua materna del alumnado, se dan más ajustes conversacionales que en las clases en lengua materna.---------------------------------------------This article pursues to describe conversational adjustments among students in CLIL classes. We wonder if there is a link between the characteristics of the interactions and the learning of non-linguistic contents and, if there is, what kind of adjustments promote such learning. CLIL classes are the ideal environments to study the link between conversational adjustments and the learning of contents because, since they are not in the students’ mother tongue, conversational adjustments occur more frequently than in classes in mother tongue.

  16. O ajuste gerencial e seus limites: a falha seqüencial em perspectiva comparada

    Directory of Open Access Journals (Sweden)

    Flávio da Cunha Rezende

    2008-08-01

    Full Text Available O artigo focaliza a explicação da falha seqüencial nas reformas gerenciais. Ele trata do problema dos limites do ajuste gerencial, em uma abordagem que tenta conectar teoria e dados empíricos, articulando três níveis de análise. O primeiro nível apresenta evidências comparativas da falha seqüencial das reformas nos governos nacionais a partir de um conjunto de indicadores voltados para compreender transformações no papel dos estados. O segundo nível analítico identifica, à luz da análise de um conjunto representativo de estudos comparativos da implementação de reformas, quatro mecanismos típicos presentes na explicação das falhas do ajuste gerencial. Busca-se configurar uma matriz explicativa de teorias sobre a falha seqüencial. Em seguida discute-se a experiência da reforma gerencial no contexto brasileiro, conferindo especial atenção para um dos mecanismos geradores da falha: o dilema do controle. As principais hipóteses são que guiam o artigo são que as reformas falham sequencialmente e existem pelo menos quatro mecanismos causais que produzem as reformas: a custos de transação envolvidos na produção das reformas; b legados de desempenho; c preponderância do ajuste fiscal e d o dilema do controle. Esses mecanismos atuam isolada ou combinadamente, reduzindo consideravelmente as chances de transformações do papel do Estado nos moldes gerenciais. As principais evidências analisadas no artigo permitem tornar consistente o argumento geral de que as reformas falharam nas tentativas de reduzir os gastos públicos, alterar padrões de alocação de recursos, reduzir a força de trabalho e transformar o papel do Estado. A principal conclusão é que as reformas falharam seqüencialmente e o ajuste gerencial exibe consideráveis limites, especialmente de natureza política.

  17. Representación de la Enfermedad, Afrontamiento y Ajuste en los Trastornos Alimentarios

    Directory of Open Access Journals (Sweden)

    Yolanda Quiles Marcos

    2009-01-01

    Full Text Available El objetivo de esta investigación es evaluar la representación de la enfermedad en pacientes con un trastorno alimentario (TA, así como su relación con el afrontamiento y el ajuste, utilizando como marco teórico el Modelo del Sentido Común de Leventhal. Método: Participaron 98 mujeres diagnosticadas de un TA. La media de edad fue 20.8 años (dt=5.61. Para evaluar la representación de la enfermedad se administró la adaptación española para los TA del Cuestionario de Percepción de la Enfermedad Revisado (IPQ-R. Resultados: Respecto a la identidad, los síntomas más señalados fueron la "pérdida de peso" (89.8% y las "alteraciones en la menstruación" (81.6%. Consideran que su enfermedad tiene una larga duración y serias consecuencias, así como que tienen control y siguiendo un tratamiento es posible su curación. El 21% de la varianza de las estrategias evitativas fue explicado por diferentes dimensiones de la representación de la enfermedad. Se confirman los efectos directos de la representación de la enfermedad sobre el ajuste, pero no los del afrontamiento. Conclusiones: Los resultados apoyan la necesidad de intervenir sobre las creencias que tienen estas pacientes sobre su enfermedad con el fin de mejorar su ajuste psicosocial.

  18. Manufacturing plant control challenges and issues

    OpenAIRE

    Morel, Gérard; Valckenaers, Paul; Faure, Jean-Marc; Pereira, Carlos Eduardo; Diedrich, Christian

    2007-01-01

    International audience; Enterprise control system integration between business systems, manufacturing execution systems and shop-floor process-control systems remains a key issue for facilitating the deployment of plant-wide information control systems for practical e-business-to-manufacturing industry-led issues. Achievement of the integration-in-manufacturing paradigm based on centralized/distributed hardware/software automation architectures is evolving using the intelligence-in-manufactur...

  19. Injuries to plants from controlled environment contaminants

    Science.gov (United States)

    Tibbitts, T. W.

    The use of controlled environments is subject to problems from contaminants emitted from materials of the system and from plants. Many contaminants are difficult to identify because injurious dosages are very low, there is a lack of information on what compounds injure plants, because species and cultivars differ greatly in their sensitivity to injury and injury symptoms often are not distinctive. Plastics have been shown to emit many different volatile compounds. The compound, di-butyl phthalate, contained in certain flexible plastics, has been shown to be very toxic to plants. Other injuries have been produced by caulking compounds and bonded screening. Paints have been shown to release xylene that is toxic to plants. Steam for humidification can cause problems because of hydroxylamines and other compounds added to steam used for heating to control fungal growth in return lines. Mercury, from broken thermometers is a particular problem in growth chambers because small quantities can collect in cracks and slowly volatilize to slow growth of plants. Plants themselves release large quantities of volatile hydrocarbons, with ethylene being the commonly recognized chemical that can be damaging when allowed to accumulate. People release large quantities of carbon dioxide which can cause variations in the rate of growth of plants. Contaminant problems can be controlled through filtering of the air or ventilation with make-up air, however the potential for problems is always present and careful testing should be undertaken with the particular species and cultivars being grown to insure that there are no toxic agents altering growth in each particular controlled environment being utilized.

  20. Nuclear reactor kinetics and plant control

    CERN Document Server

    Oka, Yoshiaki

    2013-01-01

    Understanding time-dependent behaviors of nuclear reactors and the methods of their control is essential to the operation and safety of nuclear power plants. This book provides graduate students, researchers, and engineers in nuclear engineering comprehensive information on both the fundamental theory of nuclear reactor kinetics and control and the state-of-the-art practice in actual plants, as well as the idea of how to bridge the two. The first part focuses on understanding fundamental nuclear kinetics. It introduces delayed neutrons, fission chain reactions, point kinetics theory, reactivit

  1. Internal transport control in pot plant production

    NARCIS (Netherlands)

    Annevelink, E.

    1999-01-01

    Drawing up internal transport schedules in pot plant production is a very complex task. Scheduling internal transport at the operational level and providing control on a day-to-day or even hour-to-hour basis in particular requires a new approach. A hierarchical planning approach based on

  2. Policentrismo urbano y ajuste del sistema de ciudades en Galicia

    OpenAIRE

    Precedo Ledo, Andrés; Míguez Iglesias, Alberto

    2012-01-01

    El sistema urbano de Galicia constituye un caso interesante para estudiar la evolución y ajuste de un sistema policéntrico de ciudades a la etapa postindustrial, así como su apertura al sistema urbano global. En este estudio partimos de la hipótesis de que las ciudades medias pueden posicionarse como ciudades subglobales mediante procesos de innovación y creatividad, que aportan una ventaja comparativa de competitividad basada en la calidad de vida. También en esto las ciudades...

  3. Add Control: plant virtualization for control solutions in WWTP.

    Science.gov (United States)

    Maiza, M; Bengoechea, A; Grau, P; De Keyser, W; Nopens, I; Brockmann, D; Steyer, J P; Claeys, F; Urchegui, G; Fernández, O; Ayesa, E

    2013-01-01

    This paper summarizes part of the research work carried out in the Add Control project, which proposes an extension of the wastewater treatment plant (WWTP) models and modelling architectures used in traditional WWTP simulation tools, addressing, in addition to the classical mass transformations (transport, physico-chemical phenomena, biological reactions), all the instrumentation, actuation and automation & control components (sensors, actuators, controllers), considering their real behaviour (signal delays, noise, failures and power consumption of actuators). Its ultimate objective is to allow a rapid transition from the simulation of the control strategy to its implementation at full-scale plants. Thus, this paper presents the application of the Add Control simulation platform for the design and implementation of new control strategies at the WWTP of Mekolalde.

  4. Epigenetic control of effectors in plant pathogens

    Directory of Open Access Journals (Sweden)

    Mark eGijzen

    2014-11-01

    Full Text Available Plant pathogens display impressive versatility in adapting to host immune systems. Pathogen effector proteins facilitate disease but can become avirulence (Avr factors when the host acquires discrete recognition capabilities that trigger immunity. The mechanisms that lead to changes to pathogen Avr factors that enable escape from host immunity are diverse, and include epigenetic switches that allow for reuse or recycling of effectors. This perspective outlines possibilities of how epigenetic control of Avr effector gene expression may have arisen and persisted in plant pathogens, and how it presents special problems for diagnosis and detection of specific pathogen strains or pathotypes.

  5. On fuzzy control of water desalination plants

    Energy Technology Data Exchange (ETDEWEB)

    Titli, A. [Centre National de la Recherche Scientifique (CNRS), 31 - Toulouse (France); Jamshidi, M. [New Mexico Univ., Albuquerque, NM (United States); Olafsson, F. [Institute of Technology, Norway (Norway)

    1995-12-31

    In this report we have chosen a sub-system of an MSF water desalination plant, the brine heater, for analysis, synthesis, and simulation. This system has been modelled and implemented on computer. A fuzzy logic controller (FLC) for the top brine temperature control loop has been designed and implemented on the computer. The performance of the proposed FLC is compared with three other conventional control strategies: PID, cascade and disturbance rejection control. One major concern on FLC`s has been the lack of stability criteria. An up to-date survey of stability of fuzzy control systems is given. We have shown stability of the proposed FLC using the Sinusoidal Input Describing Functions (SIDF) method. The potential applications of fuzzy controllers for complex and large-scale systems through hierarchy of rule sets and hybridization with conventional approaches are also investigated. (authors)

  6. Control effect of lanthanum against plant disease

    Institute of Scientific and Technical Information of China (English)

    LIU Yajia; WANG Yan; WANG Fubin; LIU Yuming; CUI Jianyu; HU Lin; MU Kangguo

    2008-01-01

    Effect of La on emergence, growth and development of Isatis indigotica Fort and Festuca arundinacea seedlings was researched by pot experiments of inoculating Rhizoctonia solani and with the mixture of Rhizoctonia solani and Fusarium solani in disinfected soil after the seeds were soaked in the solution with different concentrations of La3+. The results indicated that infection rate decreased and there were significant disease controlling effects on seed rot, bud rot and root rot caused by pathogenic fungi when the seeds were soaked by La3+. Thus, the rates of emergence of Isatis indigotica Fort. And turfgrass Festuca arundinacea were increased. When La3+ concentration was in a proper range, the growth and development of plant seedlings were promoted. Spraying La on rice plants showed a significant controling effect on Rhizoctonia solani. Furthermore, the EC50 of La3+ performed 128.7 and 128.1 mg/L at 1 and 7 d after spraying La in rice plants, respectively. The EC50ofLa3+ performed in vivo (in rice plant) was lower than that in vitro (171.9 mg/L).

  7. A metamorphic controller for plant control system design

    Directory of Open Access Journals (Sweden)

    Tomasz Klopot

    2016-07-01

    Full Text Available One of the major problems in the design of industrial control systems is the selection and parameterization of the control algorithm. In practice, the most common solution is the PI (proportional-integral controller, which is simple to implement, but is not always the best control strategy. The use of more advanced controllers may result in a better efficiency of the control system. However, the implementation of advanced control algorithms is more time-consuming and requires specialized knowledge from control engineers. To overcome these problems and to support control engineers at the controller design stage, the paper describes a tool, i.e., a metamorphic controller with extended functionality, for selection and implementation of the most suitable control algorithm. In comparison to existing solutions, the main advantage of the metamorphic controller is its possibility of changing the control algorithm. In turn, the candidate algorithms can be tested through simulations and the total time needed to perform all simulations can be less than a few minutes, which is less than or comparable to the design time in the concurrent design approach. Moreover, the use of well-known tuning procedures, makes the system easy to understand and operate even by inexperienced control engineers. The application was implemented in the real industrial programmable logic controller (PLC and tested with linear and nonlinear virtual plants. The obtained simulation results confirm that the change of the control algorithm allows the control objectives to be achieved at lower costs and in less time.

  8. Concept and controllability of virtual power plant

    Energy Technology Data Exchange (ETDEWEB)

    Setiawan, E.A.

    2007-07-01

    In the end of 20th century the conception of electrical power supply is morphing gradually from centralized into decentralized system, indicated by increasing the installation of distributed generation on the main grid. With emerging of advanced communication and information technology, the aggregation control of several DG units can be developed as virtual power plant in order to provide added-value to the electric power system. This thesis presents definitions and types of Virtual Power Plants (VPP), then developing control through numerical simulation. The thesis proposes three DG controls namely Basic Autocontrol System (BAS), Smart Autocontrol System (SAS) and Tracking Efficiency Autocontrol System (TEAS). The BAS controls the DG output power with the objective to cover the local load demand. The drawback of this system is that the coordination among DG units is not established yet. In contrast to the BAS, the SAS has a control coordination centre which is responsible of controlling a certain number of DG units. The SAS controls and coordinates the operation of the dedicated DG units in order to minimize power exchange with the superior grid. However the efficiency issue is not considered at two previous control systems, therefore the TEAS was developed. Principally this system is similar to the SAS in terms of information exchange but additionally optimizes the operation efficiency of DG units. This is accomplished by tracking the systems' most efficient operation point. All control systems have been implemented into a simulation environment. The simulation results show that all developed control systems are capable to minimize the power exchange with the superior grid. The systems are able to follow changing load conditions. Furthermore the simulation results prove the ability of TEAS to optimize the system efficiency. Finally the contribution of VPP to voltage regulation is investigated with several scenarios. The influence of both, active and reactive

  9. Solar field control for desalination plants

    Energy Technology Data Exchange (ETDEWEB)

    Roca, Lidia [Convenio Universidad de Almeria, Plataforma Solar de Almeria, Ctra. Senes s/n, 04200 Tabernas, Almeria (Spain); Berenguel, Manuel [Universidad de Almeria, Dpto. Lenguajes y Computacion, Ctra. Sacramento s/n, 04120 Almeria (Spain); Yebra, Luis; Alarcon-Padilla, Diego C. [CIEMAT, Plataforma Solar de Almeria, Ctra. Senes s/n, 04200 Tabernas, Almeria (Spain)

    2008-09-15

    This paper presents the development and application of a feedback linearization control strategy for a solar collector field supplying process heat to a multi-effect seawater distillation plant. Since one objective is to use as much as possible the solar resource, control techniques can be used to produce the maximum heat process in the solar field. The main purpose of the controller presented in this paper is to manipulate the water flow rate to maintain an outlet-inlet temperature gradient in the collectors, thereby ensuring continuous process heating, or in other words, continuous production of fresh water in spite of disturbances. The dynamic behaviour of this solar field was approximated by a simplified lumped-parameters nonlinear model based on differential equations, validated with real data and used in the feedback linearization control design. Experimental results in the seawater desalination plant at the Plataforma Solar de Almeria (Spain) show good agreement of the model and real data despite the approximations included. Moreover, by using feedback linearization control it is possible to track a constant gradient temperature reference in the solar field with good results. (author)

  10. Overall control and monitoring systems for pumped storage plants

    Energy Technology Data Exchange (ETDEWEB)

    Stepinski, B.; Cvetko, H.

    1982-01-01

    Experience and technical innovations in power plant engineering have resulted in continuous improvements of operation control, availability and safety of pumped storage plants. Process control is constantly improved as new developments are made in equipment and systems engineering. Plant control concepts with increasingly complex automation hierarchy are described by which pumped storage processes can be controlled optimally, reliably, and automatically.

  11. Autonomous Control of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Basher, H.

    2003-10-20

    A nuclear reactor is a complex system that requires highly sophisticated controllers to ensure that desired performance and safety can be achieved and maintained during its operations. Higher-demanding operational requirements such as reliability, lower environmental impacts, and improved performance under adverse conditions in nuclear power plants, coupled with the complexity and uncertainty of the models, necessitate the use of an increased level of autonomy in the control methods. In the opinion of many researchers, the tasks involved during nuclear reactor design and operation (e.g., design optimization, transient diagnosis, and core reload optimization) involve important human cognition and decisions that may be more easily achieved with intelligent methods such as expert systems, fuzzy logic, neural networks, and genetic algorithms. Many experts in the field of control systems share the idea that a higher degree of autonomy in control of complex systems such as nuclear plants is more easily achievable through the integration of conventional control systems and the intelligent components. Researchers have investigated the feasibility of the integration of fuzzy logic, neural networks, genetic algorithms, and expert systems with the conventional control methods to achieve higher degrees of autonomy in different aspects of reactor operations such as reactor startup, shutdown in emergency situations, fault detection and diagnosis, nuclear reactor alarm processing and diagnosis, and reactor load-following operations, to name a few. With the advancement of new technologies and computing power, it is feasible to automate most of the nuclear reactor control and operation, which will result in increased safety and economical benefits. This study surveys current status, practices, and recent advances made towards developing autonomous control systems for nuclear reactors.

  12. Neural Network Based PID Gain Tuning of Chemical Plant Controller

    Science.gov (United States)

    Abe, Yoshihiro; Konishi, Masami; Imai, Jun; Hasegawa, Ryusaku; Watanabe, Masamori; Kamijo, Hiroaki

    In these years, plant control systems are highly automated and applied to many industries. The control performances change with the passage of time, because of the deterioration of plant facilities. This is why human experts tune the control system to improve the total plant performances. In this study, PID control system for the oil refining chemical plant process is treated. In oil refining, there are thousands of the control loops in the plant to keep the product quality at the desired value and to secure the safety of the plant operation. According to the ambiguity of the interference between control loops, it is difficult to estimate the plant dynamical model accurately. Using neuro emulator and recurrent neural networks model (RNN model) for emulation and tuning parameters, PID gain tuning system of chemical plant controller is constructed. Through numerical experiments using actual plant data, effect of the proposed method was ascertained.

  13. Revocatoria del mandato: experiencias, dificultades y ajustes necesarios

    Directory of Open Access Journals (Sweden)

    William W. Jimu00E9nez

    2001-01-01

    Full Text Available En 1994 se introdujo en Colombia la figura de la Revocatoria del Mandato a los alcaldes y gobernadores como mecanismo tendiente al fortalecimiento de la democracia local. El presente artículo realiza un análisis de los 10 casos de revocatorias realizados hasta el 2.000. Con base en datos electorales registrados, la opinión de algunos expertos y el testimonio directo de actores involucrados; se presentan las dificultades, logros y limitaciones encontrados. En general, se observa la inoperancia, poco uso, alta abstención electoral e ineficacia política de la revocatoria. Finalmente, se realizan algunas recomendaciones con miras a realizar ajustes necesarios y urgentes.

  14. Efectos de entrenar para cumplir criterios de congruencia en tareas de ajuste lector

    Directory of Open Access Journals (Sweden)

    Germán Morales-Chávez

    2010-01-01

    Full Text Available La presente investigación evaluó los efectos de entrenar estudiantes universitarios para satisfacer criterios de congruencia en tareas de ajuste lector con base en parámetros de congruencia y de coherencia. El grupo experimental fue entrenado para satisfacer criterios de congruencia y fue expuesto a dos pruebas de evaluación en satisfacción de criterios de congruencia y coherencia. El grupo control solo fue sometido a las pruebas de evaluación. Los resultados revelan que el entrenamiento favoreció la satisfacción de criterios tanto de congruencia como de coherencia. Se discute la relevancia del desempeño efectivo en una situación lectora con criterios de congruencia como condición para el desarrollo de conductas lectoras funcionalmente más complejas.

  15. EFECTOS DE ENTRENAR PARA CUMPLIR CRITERIOS DE CONGRUENCIA EN TAREAS DE AJUSTE LECTOR

    Directory of Open Access Journals (Sweden)

    Germán Morales-Chávez

    2010-01-01

    Full Text Available La presente investigación evaluó los efectos de entrenar estudiantes universitarios para satisfacer criterios de congruenciaen tareas de ajuste lector con base en parámetros de congruenciay de coherencia. El grupo experimental fue entrenadopara satisfacer criterios de congruencia y fue expuestoa dos pruebas de evaluación en satisfacción de criterios decongruencia y coherencia. El grupo control solo fue sometidoa las pruebas de evaluación. Los resultados revelan que elentrenamiento favoreció la satisfacción de criterios tanto decongruencia como de coherencia. Se discute la relevancia deldesempeño efectivo en una situación lectora con criterios decongruencia como condición para el desarrollo de conductaslectoras funcionalmente más complejas.

  16. Instituições, política e ajuste fiscal: o Brasil em perspectiva comparada

    Directory of Open Access Journals (Sweden)

    Loureiro Maria Rita

    2001-01-01

    Full Text Available Neste texto examinam-se as condições institucionais e políticas do ajuste fiscal. Mesmo considerando que as instituições afetam as estratégias dos atores e os resultados das políticas, supõe-se que o cumprimento das regras relativas ao controle fiscal dependem igualmente de certas condições políticas contingentes, como a coesão governamental. Embora a análise seja centrada no Brasil recente, são também confrontados casos de outros países - Estados Unidos, Holanda e Suécia - que também enfrentaram sérios problemas fiscais nos anos 80.

  17. Gaseous emissions from plants in controlled environments

    Science.gov (United States)

    Dubay, Denis T.

    1988-01-01

    Plant growth in a controlled ecological life support system may entail the build-up over extended time periods of phytotoxic concentrations of volatile organic compounds produced by the plants themselves. Ethylene is a prominent gaseous emission of plants, and is the focus of this report. The objective was to determine the rate of ethylene release by spring wheat, white potato, and lettuce during early, middle, and late growth stages, and during both the light and dark segments of the diurnal cycle. Plants grown hydroponically using the nutrient film technique were covered with plexiglass containers for 4 to 6 h. At intervals after enclosure, gas samples were withdrawn with a syringe and analyzed for ethylene with a gas chromatograph. Lettuce produced 10 to 100 times more ethylene than wheat or potato, with production rates ranging from 141 to 158 ng g-dry/wt/h. Wheat produced from 1.7 to 14.3 ng g-dry/wt/h, with senescent wheat producing the least amount and flowering wheat the most. Potatoes produced the least amount of ethylene, with values never exceeding 5 ng g-dry/wt/h. Lettuce and potatoes each produced ethylene at similar rates whether in dark period or light period. Ethylene sequestering of 33 to 43 percent by the plexiglass enclosures indicated that these production estimates may be low by one-third to one-half. These results suggest that concern for ethylene build-up in a contained atmosphere should be greatest when growing lettuce, and less when growing wheat or potato.

  18. Multilevel Flow Modelling of Process Plant for Diagnosis and Control

    DEFF Research Database (Denmark)

    Lind, Morten

    1982-01-01

    of complex systems. A model of a nuclear power plant (PWR) is presented in the paper for illustration. Due to the consistency of the method, multilevel flow models provide specifications of plant goals and functions and may be used as a basis for design of computer-based support systems for the plant...... operator. Plant control requirements can be derived from the models and due to independence of the actual controller implementation the method may be used as a basis for design of control strategies and for the allocation of control tasks to the computer and the plant operator....

  19. Una década de ajuste estructural en Nicaragua

    Directory of Open Access Journals (Sweden)

    Oscar Catalán Aravena.

    2001-12-01

    Full Text Available Se analizan las políticas macroeconómicas de estabilización y ajuste estructural llevadas a cabo en Nicaragua durante el último decenio y se trata de explicar el porqué de los pobres resultados obtenidos. Aunque el país vivió en ese período una elevadísima polarización, las políticas aplicadas han tenido continuidad y sus contenidos han sido similares durante los tres períodos de gobierno analizados. En este análisis se distinguen cuatro fases: 1988-1989 de reformas del Gobierno Sandinista; 1990-1993 en que el Gobierno de Barrios de Chamorro controla la hiperinflación e implementa el primer acuerdo "stand by" con el FMI; 1994-1996 en que el mismo gobierno implementa el primer acuerdo Enhanced Structural Adjustment Facilities (ESAF con el FMI y se inicia la recuperación económica; y 1997 en que, bajo la presidencia de Alemán, se implementa el segundo acuerdo ESAF con el FMI.

  20. Macrofouling control in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ekis, E.W. Jr.; Keoplin-Gall, S.M.; McCarthy, R.E.

    1991-11-01

    Macrofouling of cooling-water systems is one of the more significant and costly problems encountered in the nuclear power industry. Both marine and freshwater macroinvertebrates can be responsible for losses in plant availability because of plugged intakes and heat transfer equipment. There is a greater diversity of macrofouling organisms in marine waters than in fresh waters. Marine macrofouling organisms include barnacles, mollusks, bryozoans, and hydroids. Barnacles are crustaceans with feathery appendages, which allow them to attach to a variety of surfaces. They are a major cause of severe macrofouling because they can remain attached even after death. The major freshwater macrofouling organisms include the Asiatic Clam (Corbicula fluminea) and the newest freshwater macrofouler, the Zebra Mussel (Dreissena polymorpha). The introduction of the Zebra Mussel into the Great Lakes has created economic and ecological problems that will not easily be solved. The threat of intercontinental dispersal of the Zebra Mussel in America is serious. Research programs have been initiated around the country to develop control methods for this macrofouling problem. The various control methodologies can be classified in the following categories: biological, chemical, physical, and mechanical. Laboratory experiments were performed to evaluate the efficacy of Actibrom against mature Zebra Mussels.

  1. Cronograma de amostragem de plantas de alface hidropônica para ajuste de curvas de crescimento Hydroponic lettuce sampling chronogram for fitting growth curves

    Directory of Open Access Journals (Sweden)

    Paula Machado dos Santos

    2007-12-01

    Full Text Available O ajuste de curvas de crescimento de plantas de alface durante seu ciclo necessita de amostragens no tempo, o que restringe o número de efeitos de tratamentos estudados. Com o objetivo de determinar o cronograma de amostragem de plantas de alface em hidroponia para o ajuste de curvas de crescimento até a fase de maturação das sementes, foram realizados dois cultivos em casa de vegetação durante a primavera e o outono, em área pertencente ao Departamento de Fitotecnia, na UFSM, Santa Maria, RS. A partir do ajuste de um modelo de crescimento com amostragem diária, simularam-se diferentes cronogramas de amostragem para o ajuste do mesmo modelo. Para encontrar o cronograma de maior intervalo entre amostragens, ou seja, menor número de coletas, foi comparado o ajuste do modelo de amostragem diária com os ajustes dos modelos dos diferentes intervalos de amostragens simulados, dois a dois, pelo teste F. Foram realizadas simulações considerando desde a data de transplante até a produção de sementes, para variáveis de fitomassa seca da planta e de partes da planta e área foliar. Em experimentos realizados com alface hidropônica na primavera, para o ciclo completo, recomendam-se amostragens a cada 3, 8, 20 e 9 dias para fitomassa seca relativa total da planta de alface, de folhas, de raiz e área foliar, respectivamente; enquanto que, para experimentos realizados no outono, é recomendável utilizar intervalos de amostragens a cada 2, 11, 12 e 11 dias, respectivamente.The fitting of growth curves for lettuce plants requires many samplings within o time interval, while can restrict the number of studied treatments. With the aim o determine sampling chronogram hidroponic lettuce for the fitting of growth curves until maturation of seeds. Two greenhouse trials were carried out in spring an autumn, at UFSM experimental area, Santa Maria, RS. Different sampling interval were simulated using the fitting of a daily model. The optimum sampling

  2. Selection Guidelines for Central Heat Plant Controls.

    Science.gov (United States)

    1994-11-01

    21 PID Controllers ............................................... 22 Combustion Control...Therefore, closed-loop control is preferred for boiler control. PID Controllers Figure 9 shows the basic functions of a closed loop controller

  3. Best Tracking Performance under Plant Uncertainty and Control Energy Constraint

    Institute of Scientific and Technical Information of China (English)

    KONG Yi-gang; WANG Zhi-xin; WANG Jian-guo

    2007-01-01

    This paper has investigated best tracking performance for linear feedback control systems in the case that plant uncertainty and control effort need to be considered simultaneously. Firstly, an average integral square criterion of the tracking error and the plant input energy over a class of additive model errors is defined. Then, utilizing spectral factorization to minimize the performance index, we obtain an optimal controller design method, and furthermore study optimal tracking performance under plant uncertainty and control energy constraint. The results can be used to evaluate optimal average tracking performance and control energy in designing practical control systems.

  4. Agricultural Plant Pest Control. Bulletin 763.

    Science.gov (United States)

    French, John C.; And Others

    This manual gives general information on plant pests and pesticides. First, the life-cycle and habits of some common insect pests are given. These include caterpillars, beetles and beetle larvae, and sucking insects. Next, plant diseases such as leaf diseases, wilts, root and crown rots, stem cankers, fruit rots, seed and seedling diseases, and…

  5. Agricultural Plant Pest Control. Bulletin 763.

    Science.gov (United States)

    French, John C.; And Others

    This manual gives general information on plant pests and pesticides. First, the life-cycle and habits of some common insect pests are given. These include caterpillars, beetles and beetle larvae, and sucking insects. Next, plant diseases such as leaf diseases, wilts, root and crown rots, stem cankers, fruit rots, seed and seedling diseases, and…

  6. Soil microorganisms control plant ectoparasitic nematodes in natural coastal foredunes

    NARCIS (Netherlands)

    Piskiewicz, A.M.; Duyts, H.; Berg, M.P.; Costa, S.R.; Putten, van der W.H.

    2007-01-01

    Belowground herbivores can exert important controls on the composition of natural plant communities. Until now, relatively few studies have investigated which factors may control the abundance of belowground herbivores. In Dutch coastal foredunes, the root-feeding nematode Tylenchorhynchus ventralis

  7. Overall control and monitoring systems for pumped storage plants

    Energy Technology Data Exchange (ETDEWEB)

    Stepinski, B.; Cvetko, H.

    1982-06-01

    The article describes control and monitoring concepts in which the delegation of responsibility is becoming more decisive than ever (automation hierarchy), and which are capable of optimized, automatic control of process events in pumped storage plants. 8 refs.

  8. Soil microorganisms control plant ectoparasitic nematodes in natural coastal foredunes

    NARCIS (Netherlands)

    Piskiewicz, A.M.; Duyts, H.; Berg, M.P.; Costa, S.R.; Putten, van der W.H.

    2007-01-01

    Belowground herbivores can exert important controls on the composition of natural plant communities. Until now, relatively few studies have investigated which factors may control the abundance of belowground herbivores. In Dutch coastal foredunes, the root-feeding nematode Tylenchorhynchus ventralis

  9. Process plant equipment operation, control, and reliability

    CERN Document Server

    Holloway, Michael D; Onyewuenyi, Oliver A

    2012-01-01

    "Process Plant Equipment Book is another great publication from Wiley as a reference book for final year students as well as those who will work or are working in chemical production plants and refinery…" -Associate Prof. Dr. Ramli Mat, Deputy Dean (Academic), Faculty of Chemical Engineering, Universiti Teknologi Malaysia "…give[s] readers access to both fundamental information on process plant equipment and to practical ideas, best practices and experiences of highly successful engineers from around the world… The book is illustrated throughout with numerous black & white p

  10. EXTERNAL AND INTERNAL CONTROL IN PLANT DEVELOPMENT

    Institute of Scientific and Technical Information of China (English)

    Beáta Oborny

    2003-01-01

    Bodies of plants are modularly organized. Development proceeds by adding new modules to open endings with a potential for branching. Each module is autonomous to some extent. Development relies on the self-organized patterns that emerge from the interactions of individual modules. Interactions include both competition and cooperation, and several types of positive and negative feedback loops are involved. Development can be open to external influences, thus enabling the plant to adjust its form to the environment, for example, to the spatial distribution of ecological resources. This paper provides a review on adaptive plasticity in plants.

  11. Automated detection and control of volunteer potato plants

    NARCIS (Netherlands)

    Nieuwenhuizen, A.T.

    2009-01-01

    High amounts of manual labor are needed to control volunteer potato plants in arable fields. Due to the high costs, this leads to incomplete control of these weed plants, and they spread diseases like Phytophthora infestans to other fields. This results in higher environmental loads by curative

  12. Automated detection and control of volunteer potato plants

    NARCIS (Netherlands)

    Nieuwenhuizen, A.T.

    2009-01-01

    High amounts of manual labor are needed to control volunteer potato plants in arable fields. Due to the high costs, this leads to incomplete control of these weed plants, and they spread diseases like Phytophthora infestans to other fields. This results in higher environmental loads by curative spra

  13. Automated detection and control of volunteer potato plants

    NARCIS (Netherlands)

    Nieuwenhuizen, A.T.

    2009-01-01

    High amounts of manual labor are needed to control volunteer potato plants in arable fields. Due to the high costs, this leads to incomplete control of these weed plants, and they spread diseases like Phytophthora infestans to other fields. This results in higher environmental loads by curative spra

  14. The Class of Stabilizing Nonlinear Plant Controller Pairs

    NARCIS (Netherlands)

    Paice, A.D.B.; Schaft, Arjan J. van der

    1996-01-01

    In this paper a general approach is taken to yield a characterization of the class of stable plant controller pairs which is a generalization of the Youla parameterization for linear systems. This is based on the idea of representing the input-output pairs of the plant and controller as elements of

  15. Choosing Actuators for Automatic Control Systems of Thermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Gorbunov, A. I., E-mail: gor@tornado.nsk.ru [JSC “Tornado Modular Systems” (Russian Federation); Serdyukov, O. V. [Siberian Branch of the Russian Academy of Sciences, Institute of Automation and Electrometry (Russian Federation)

    2015-03-15

    Two types of actuators for automatic control systems of thermal power plants are analyzed: (i) pulse-controlled actuator and (ii) analog-controlled actuator with positioning function. The actuators are compared in terms of control circuit, control accuracy, reliability, and cost.

  16. Ajustes Contábeis para o Cálculo do EVA: estudo sobre os procedimentos adotatos em empresas brasileiras

    Directory of Open Access Journals (Sweden)

    Eduardo Kazuo Kayo

    2008-06-01

    Full Text Available A geração de valor para o acionista está se tornando uma preocupação cada vez mais presente em resposta à pressão dos investidores e de conselhos de administração. Várias abordagens estão disponíveis, entre estas, uma linha de pensamento ligada ao Lucro Residual, o Valor Econômico Agregado (EVA, metodologia desenvolvida pela Stern Stewart & Co. Para cor-rigir as impropriedades percebidas na prática das demonstrações financeiras, alguns usuários da técnica do EVA ajustam os dados contábeis de acordo com os Princípios Contábeis Geralmente Aceitos, na expectativa de que tais ajustes produzam valores mais confiáveis e possam gerar ambiente propício aos comportamentos administrativos mais próximos ao ótimo esperado. A lógica e a mecânica por trás desses ajustes são tratadas ao longo do trabalho, investigando a possível correlação entre a percepção de entendimento do controller e a utilização dos métodos adotados pela organização.

  17. Controllability analysis and decentralized control of a wet limestone flue gas desulfurization plant

    Energy Technology Data Exchange (ETDEWEB)

    Perales, A.L.V.; Ortiz, F.J.G.; Ollero, P.; Gil, F.M. [University of Seville, Seville (Spain)

    2008-12-15

    Presently, decentralized feedback control is the only control strategy used in wet limestone flue gas desulfurization (WLFGD) plants. Proper tuning of this control strategy is becoming an important issue in WLFGD plants because more stringent SO{sub 2} regulations have come into force recently. Controllability analysis is a highly valuable tool for proper design of control systems, but it has not been applied to WLFGD plants so far. In this paper a decentralized control strategy is designed and applied to a WLFGD pilot plant taking into account the conclusions of a controllability analysis. The results reveal that good SO{sub 2} control in WLFGD plants can be achieved mainly because the main disturbance of the process is well-aligned with the plant and interactions between control loops are beneficial to SO{sub 2} control.

  18. Development of Plant Control Diagnosis Technology and Increasing Its Applications

    Science.gov (United States)

    Kugemoto, Hidekazu; Yoshimura, Satoshi; Hashizume, Satoru; Kageyama, Takashi; Yamamoto, Toru

    A plant control diagnosis technology was developed to improve the performance of plant-wide control and maintain high productivity of plants. The control performance diagnosis system containing this technology picks out the poor performance loop, analyzes the cause, and outputs the result on the Web page. Meanwhile, the PID tuning tool is used to tune extracted loops from the control performance diagnosis system. It has an advantage of tuning safely without process changes. These systems are powerful tools to do Kaizen (continuous improvement efforts) step by step, coordinating with the operator. This paper describes a practical technique regarding the diagnosis system and its industrial applications.

  19. A systematic methodology for controller tuning in wastewater treatment plants

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Jørgensen, S.B.; Sin, G.

    2012-01-01

    Wastewater treatment plants are typically subject to continuous disturbances caused by influent variations which exhibits diurnal patterns as well as stochastic changes due to rain and storm water events. In order to achieve an efficient operation, the control system of the plant should be able...... to respond appropriately and reject these disturbances in the influent. A methodology is described here which systematically addresses the assessment of the plant and the influent dynamics, in order to propose a controller tuning that is best adapted to an existing or planned wastewater treatment plant...

  20. Benchmarking of Control Strategies for Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Wastewater treatment plants are large non-linear systems subject to large perturbations in wastewater flow rate, load and composition. Nevertheless these plants have to be operated continuously, meeting stricter and stricter regulations. Many control strategies have been proposed in the literature...... for improved and more efficient operation of wastewater treatment plants. Unfortunately, their evaluation and comparison – either practical or based on simulation – is difficult. This is partly due to the variability of the influent, to the complexity of the biological and biochemical phenomena......, plant layout, controllers, sensors, performance criteria and test procedures, i.e. a complete benchmarking protocol....

  1. Predicción del Ajuste Diádico en una Muestra Nuevoleonesa

    Directory of Open Access Journals (Sweden)

    Jose Moral de la Rubia

    2008-01-01

    Full Text Available El objetivo del presente estudio es predecir el ajuste diádico con variables sociodemográficas, religiosas, sexuales, de estados emocionales y personalidad. La muestra consta de 100 parejas casadas. Como instrumento de medida se emplea un cuestionario integrado por preguntas cerradas y escalas para medir ajuste diádico, satisfacción sexual, alexitimia, ansiedad, depresión, afectos positivos y negativos, deseabilidad social y engrandecimiento marital. Los datos se analizan por correlación, análisis factorial y regresión. El ajuste diádico se asocia con el engrandecimiento marital, ansiedad-rasgo, satisfacción sexual; con alexitimia y depresión especialmente en hombres; y con menor fuerza, con niveles bajos de afectos negativos y altos de positivos. Al factorizar los correlatos interrelacionados del ajuste diádico surge un factor de neuroticismo y emociones negativas que es el principal predictor de falta de ajuste. Se considera que el engrandecimiento marital se debe interpretar como autoengaño y enamoramiento mejor que como manejo de la impresión.

  2. Optimal control and cold war dynamics between plant and herbivore.

    Science.gov (United States)

    Low, Candace; Ellner, Stephen P; Holden, Matthew H

    2013-08-01

    Herbivores eat the leaves that a plant needs for photosynthesis. However, the degree of antagonism between plant and herbivore may depend critically on the timing of their interactions and the intrinsic value of a leaf. We present a model that investigates whether and when the timing of plant defense and herbivore feeding activity can be optimized by evolution so that their interactions can move from antagonistic to neutral. We assume that temporal changes in environmental conditions will affect intrinsic leaf value, measured as potential carbon gain. Using optimal-control theory, we model herbivore evolution, first in response to fixed plant strategies and then under coevolutionary dynamics in which the plant also evolves in response to the herbivore. In the latter case, we solve for the evolutionarily stable strategies of plant defense induction and herbivore hatching rate under different ecological conditions. Our results suggest that the optimal strategies for both plant and herbivore are to avoid direct conflict. As long as the plant has the capability for moderately lethal defense, the herbivore will modify its hatching rate to avoid plant defenses, and the plant will never have to use them. Insights from this model offer a possible solution to the paradox of sublethal defenses and provide a mechanism for stable plant-herbivore interactions without the need for natural enemy control.

  3. Plant community controls on short-term ecosystem nitrogen retention.

    Science.gov (United States)

    de Vries, Franciska T; Bardgett, Richard D

    2016-05-01

    Retention of nitrogen (N) is a critical ecosystem function, especially in the face of widespread anthropogenic N enrichment; however, our understanding of the mechanisms involved is limited. Here, we tested under glasshouse conditions how plant community attributes, including variations in the dominance, diversity and range of plant functional traits, influence N uptake and retention in temperate grassland. We added a pulse of (15) N to grassland plant communities assembled to represent a range of community-weighted mean plant traits, trait functional diversity and divergence, and species richness, and measured plant and microbial uptake of (15) N, and leaching losses of (15) N, as a short-term test of N retention in the plant-soil system. Root biomass, herb abundance and dominant plant traits were the main determinants of N retention in the plant-soil system: greater root biomass and herb abundance, and lower root tissue density, increased plant (15) N uptake, while higher specific leaf area and root tissue density increased microbial (15) N uptake. Our results provide novel, mechanistic insight into the short-term fate of N in the plant-soil system, and show that dominant plant traits, rather than trait functional diversity, control the fate of added N in the plant-soil system.

  4. Plant growth control by light spectrum

    NARCIS (Netherlands)

    Ieperen, van W.

    2016-01-01

    Plants are sessile organisms that have to cope with their environment as it is exposed to them in nature. To do so, they developed systems to sense environmental signals and to integrate these with endogenous developmental programs. As a result, they are well equipped to survive and flourish in

  5. Plant growth control by light spectrum

    NARCIS (Netherlands)

    Ieperen, van W.

    2016-01-01

    Plants are sessile organisms that have to cope with their environment as it is exposed to them in nature. To do so, they developed systems to sense environmental signals and to integrate these with endogenous developmental programs. As a result, they are well equipped to survive and flourish in v

  6. Data-driven wind plant control

    NARCIS (Netherlands)

    Gebraad, P.M.O.

    2014-01-01

    Each wind turbine in a cluster of wind turbines (a wind power plant) can influence the performance of other turbines through the wake that forms downstream of its rotor. The wake has a reduced wind velocity, since the turbine extracts energy from the flow, and the obstruction by the wind turbine

  7. AJUSTE PSICOSOCIAL, BIENESTAR SUBJETIVO Y OCIO EN ADULTOS MAYORES JUBILADOS MEXICANOS

    Directory of Open Access Journals (Sweden)

    Christian Oswaldo Acosta Quiroz

    2015-01-01

    Full Text Available El objetivo de este estudio fue establecer la relación entre ajuste psicosocial en la jubilación,bienestar subjetivo, actividades de ocio y variables sociodemográficas en adultos mayores ju-bilados mexicanos. Participaron 181 adultos mayores con una edad media de 69.12 años y untiempo medio de jubilación de 11.21 años. Los resultados indican que el ajuste psicosocial enla jubilación y el bienestar subjetivo se relacionan significativamente entre sí y con las variablessociodemográficas de sexo, nivel de estudios, estatus de salud y estado civil. A su vez, se re-lacionan con la frecuencia de actividades de ocio (con diferencias entre hombres y mujeres.Estas variables deben tenerse en cuenta para fomentar un mayor ajuste psicosocial y bienestarsubjetivo en adultos mayores jubilados.

  8. Plant-microbe interactions and the new biotechnological methods of plant disease control.

    Science.gov (United States)

    Montesinos, E; Bonaterra, A; Badosa, E; Francés, J; Alemany, J; Llorente, I; Moragrega, C

    2002-12-01

    Plants constitute an excellent ecosystem for microorganisms. The environmental conditions offered differ considerably between the highly variable aerial plant part and the more stable root system. Microbes interact with plant tissues and cells with different degrees of dependence. The most interesting from the microbial ecology point of view, however, are specific interactions developed by plant-beneficial (either non-symbiotic or symbiotic) and pathogenic microorganisms. Plants, like humans and other animals, also become sick, but they have evolved a sophisticated defense response against microbes, based on a combination of constitutive and inducible responses which can be localized or spread throughout plant organs and tissues. The response is mediated by several messenger molecules that activate pathogen-responsive genes coding for enzymes or antimicrobial compounds, and produces less sophisticated and specific compounds than immunoglobulins in animals. However, the response specifically detects intracellularly a type of protein of the pathogen based on a gene-for-gene interaction recognition system, triggering a biochemical attack and programmed cell death. Several implications for the management of plant diseases are derived from knowledge of the basis of the specificity of plant-bacteria interactions. New biotechnological products are currently being developed based on stimulation of the plant defense response, and on the use of plant-beneficial bacteria for biological control of plant diseases (biopesticides) and for plant growth promotion (biofertilizers).

  9. Abscisic acid controlled sex before transpiration in vascular plants.

    Science.gov (United States)

    McAdam, Scott A M; Brodribb, Timothy J; Banks, Jo Ann; Hedrich, Rainer; Atallah, Nadia M; Cai, Chao; Geringer, Michael A; Lind, Christof; Nichols, David S; Stachowski, Kye; Geiger, Dietmar; Sussmilch, Frances C

    2016-10-26

    Sexual reproduction in animals and plants shares common elements, including sperm and egg production, but unlike animals, little is known about the regulatory pathways that determine the sex of plants. Here we use mutants and gene silencing in a fern species to identify a core regulatory mechanism in plant sexual differentiation. A key player in fern sex differentiation is the phytohormone abscisic acid (ABA), which regulates the sex ratio of male to hermaphrodite tissues during the reproductive cycle. Our analysis shows that in the fern Ceratopteris richardii, a gene homologous to core ABA transduction genes in flowering plants [SNF1-related kinase2s (SnRK2s)] is primarily responsible for the hormonal control of sex determination. Furthermore, we provide evidence that this ABA-SnRK2 signaling pathway has transitioned from determining the sex of ferns to controlling seed dormancy in the earliest seed plants before being co-opted to control transpiration and CO2 exchange in derived seed plants. By tracing the evolutionary history of this ABA signaling pathway from plant reproduction through to its role in the global regulation of plant-atmosphere gas exchange during the last 450 million years, we highlight the extraordinary effect of the ABA-SnRK2 signaling pathway in plant evolution and vegetation function.

  10. Aquatic Plant Control Research Program. Allelopathic Aquatic Plants for Aquatic Plant Management: A Feasibility Study

    Science.gov (United States)

    1989-10-01

    block number) FIELD GROUP SUB-GROUP Allelopathy "Bioassay . Growth inhibition. Aquatic macrophytes. Biocontrol Lena minor 19. ABSTRACT (Continue on...Bibliography of Aquatic Plant Allelopathy ........ Al 2 ALLELOPATHIC AQUATIC PLANTS FOR AQUATIC PLANT MANAGEMENT; A FEASIBILITY STUDY Introduction Background 1...nutrients, water, and other biotic effects could have overriding effects that appear as competition or allelopathy . These biotic factors must be

  11. Paradigm shift in plant growth control.

    Science.gov (United States)

    Körner, Christian

    2015-06-01

    For plants to grow they need resources and appropriate conditions that these resources are converted into biomass. While acknowledging the importance of co-drivers, the classical view is still that carbon, that is, photosynthetic CO2 uptake, ranks above any other drivers of plant growth. Hence, theory and modelling of growth traditionally is carbon centric. Here, I suggest that this view is not reflecting reality, but emerged from the availability of methods and process understanding at leaf level. In most cases, poorly understood processes of tissue formation and cell growth are governing carbon demand, and thus, CO2 uptake. Carbon can only be converted into biomass to the extent chemical elements other than carbon, temperature or cell turgor permit.

  12. Plant Disease Control by the Use of Chemicals. MP-27.

    Science.gov (United States)

    Ross, William D.; Bridgmon, George H.

    This document has been prepared as a reference manual providing information regarding plant diseases. The text concerns itself with the identification and development of infectious and non-infectious diseases and associated control measures. An appendix includes a glossary of plant pathological terms and a bibliography. (CS)

  13. Model-free adaptive control of advanced power plants

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

    2015-08-18

    A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  14. Model-free adaptive control of advanced power plants

    Science.gov (United States)

    Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

    2015-08-18

    A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  15. Rasgos psicológicos asociados al ajuste personal y social de estudiantes adolescentes

    OpenAIRE

    Droguett Latorre, Linda

    2014-01-01

    264 p. El ajuste social y personal de los estudiantes adolescentes se presenta en la actualidad como un tema muy relevante como objeto de análisis así como las posibles medidas de intervención para promoverlo. En este nuevo siglo, los avances tecnológicos y científicos promueven en los y las adolescentes cambios de actitud, de pensamiento así como de expectativas en cuanto a su futuro tanto personal como profesional y laboral, por lo que es muy importante que, tanto su ajuste personal ...

  16. AJUSTE PSICOSOCIAL, BIENESTAR SUBJETIVO Y OCIO EN ADULTOS MAYORES JUBILADOS MEXICANOS

    OpenAIRE

    Christian Oswaldo Acosta Quiroz; Javier José Vales García; Ramón René Palacio Cinco

    2015-01-01

    El objetivo de este estudio fue establecer la relación entre ajuste psicosocial en la jubilación,bienestar subjetivo, actividades de ocio y variables sociodemográficas en adultos mayores ju-bilados mexicanos. Participaron 181 adultos mayores con una edad media de 69.12 años y untiempo medio de jubilación de 11.21 años. Los resultados indican que el ajuste psicosocial enla jubilación y el bienestar subjetivo se relacionan significativamente entre sí y con las variablessociodemográficas de sexo...

  17. AJUSTE PSICOSOCIAL, BIENESTAR SUBJETIVO Y OCIO EN ADULTOS MAYORES JUBILADOS MEXICANOS

    OpenAIRE

    Christian Oswaldo Acosta Quiroz; Javier José Vales García; Ramón René Palacio Cinco

    2015-01-01

    El objetivo de este estudio fue establecer la relación entre ajuste psicosocial en la jubilación,bienestar subjetivo, actividades de ocio y variables sociodemográficas en adultos mayores ju-bilados mexicanos. Participaron 181 adultos mayores con una edad media de 69.12 años y untiempo medio de jubilación de 11.21 años. Los resultados indican que el ajuste psicosocial enla jubilación y el bienestar subjetivo se relacionan significativamente entre sí y con las variablessociodemográficas de sexo...

  18. Ridgefield - Wetland Invasive Plant Search and Control 2012

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project would expand survey, control, and monitoring efforts to detect new wetland invasive plant threats and continue reduction of the accumulation of recently...

  19. Ridgefield - Wetland Invasive Plant Search and Control 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project would expand survey, control, and monitoring efforts to detect new wetland invasive plant threats and reduce the accumulation of recently documented...

  20. Voltage Control in Wind Power Plants with Doubly Fed Generators

    DEFF Research Database (Denmark)

    Garcia, Jorge Martinez

    In this work, the process of designing a wind power plant composed of; doubly fed induction generators, a static compensator unit, mechanically switched capacitors and on-load tap changer, for voltage control is shown. The selected control structure is based on a decentralized system, since...... supplied by the doubly fed induction generator wind turbines is overcome by installing a reactive power compensator, i.e. a static compensator unit, which is coordinated with the plant control by a specific dispatcher. This dispatcher is set according to the result of the wind power plant load flow....... To release the operation of the converters during steady-state disturbances, mechanically switched capacitors are installed in the wind power plant, which due to their characteristics, they are appropriate for permanent disturbances compensation. The mechanically switched capacitors are controlled to allow...

  1. Aloe plant extracts as alternative larvicides for mosquito control

    African Journals Online (AJOL)

    SERVER

    2008-04-03

    Apr 3, 2008 ... 2Department of Biological Sciences, Egerton University, P. O. Box 536, Egerton 20107, Kenya. ... the incidence of this disease is to eradicate and control ...... effects of three plant extracts on Culex pipiens larvae (Diptera:.

  2. (Controls of the plant endomembrane-secretory pathway)

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    These studies are focused on elucidating the molecular structure of plant cell membranes with special reference to cell surface glycoproteins. The studies reported herein include use of monoclonal antibodies to characterize cell surface epitopes, construction of cDNA libraries of cell surface proteins, isolation of plant cell mutants by flow cytometry, detection of beta-glucouronidase marker enzyme systems in plants, expression go VSVG (the major envelope glycoprotein of Vesicular Stomatis Virus) in plant cells, and control of gene expression of cell membrane glycoproteins.(DT)

  3. [Controls of the plant endomembrane-secretory pathway]. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    These studies are focused on elucidating the molecular structure of plant cell membranes with special reference to cell surface glycoproteins. The studies reported herein include use of monoclonal antibodies to characterize cell surface epitopes, construction of cDNA libraries of cell surface proteins, isolation of plant cell mutants by flow cytometry, detection of beta-glucouronidase marker enzyme systems in plants, expression go VSVG (the major envelope glycoprotein of Vesicular Stomatis Virus) in plant cells, and control of gene expression of cell membrane glycoproteins.(DT)

  4. Introducing Model Predictive Control for Improving Power Plant Portfolio Performance

    DEFF Research Database (Denmark)

    Edlund, Kristian Skjoldborg; Bendtsen, Jan Dimon; Børresen, Simon

    2008-01-01

    This paper introduces a model predictive control (MPC) approach for construction of a controller for balancing the power generation against consumption in a power system. The objective of the controller is to coordinate a portfolio consisting of multiple power plant units in the effort to perform...

  5. Control of pain with topical plant medicines

    Institute of Scientific and Technical Information of China (English)

    James; David; Adams; Jr.; Xiaogang; Wang

    2015-01-01

    Pain is normally treated with oral nonsteroidal anti-inflammatory agents and opioids. These drugs are dangerous and are responsible for many hospitalizations and deaths. It is much safer to use topical preparations made from plants to treat pain, even severe pain. Topical preparations must contain compounds that penetrate the skin, inhibit pain receptors such as transient receptor potential cation channels and cyclooxygenase-2, to relieve pain. Inhibition of pain in the skin disrupts the pain cycle and avoids exposure of internal organs to large amounts of toxic compounds. Use of topical pain relievers has the potential to save many lives, decrease medical costs and improve therapy.

  6. Model Predictive Control of Integrated Gasification Combined Cycle Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    B. Wayne Bequette; Priyadarshi Mahapatra

    2010-08-31

    The primary project objectives were to understand how the process design of an integrated gasification combined cycle (IGCC) power plant affects the dynamic operability and controllability of the process. Steady-state and dynamic simulation models were developed to predict the process behavior during typical transients that occur in plant operation. Advanced control strategies were developed to improve the ability of the process to follow changes in the power load demand, and to improve performance during transitions between power levels. Another objective of the proposed work was to educate graduate and undergraduate students in the application of process systems and control to coal technology. Educational materials were developed for use in engineering courses to further broaden this exposure to many students. ASPENTECH software was used to perform steady-state and dynamic simulations of an IGCC power plant. Linear systems analysis techniques were used to assess the steady-state and dynamic operability of the power plant under various plant operating conditions. Model predictive control (MPC) strategies were developed to improve the dynamic operation of the power plants. MATLAB and SIMULINK software were used for systems analysis and control system design, and the SIMULINK functionality in ASPEN DYNAMICS was used to test the control strategies on the simulated process. Project funds were used to support a Ph.D. student to receive education and training in coal technology and the application of modeling and simulation techniques.

  7. Steigerwald - Invasive Plant Detection, Control, and Replacement with Native Plants 2010

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project would maintain and expand annual invasive plant survey, control, and monitoring on Steigerwald Lake NWR. Early detection surveys, rapid response, large...

  8. Steigerwald - Invasive Plant Detection, Control, and Replacement with Native Plants 2011

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This project would maintain and expand annual invasive plant survey, control, & monitoring on Steigerwald Lake NWR. Early detection surveys, rapid response,...

  9. Energy efficient control of a refrigeration plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Larsen, Lars F. S.

    2009-01-01

    This paper proposes a novel method for superheat and capacity control of refrigeration systems. The new idea is to control the superheat by the compressor speed and capacity by the refrigerant flow. A new low order nonlinear model of the evaporator is developed and used in a backstepping design o...... and the methods are evaluated with respect to energy efficiency....

  10. Quality control of plant food supplements.

    Science.gov (United States)

    Sanzini, Elisabetta; Badea, Mihaela; Santos, Ariana Dos; Restani, Patrizia; Sievers, Hartwig

    2011-12-01

    It is essential to guarantee the safety of unprocessed plants and food supplements if consumers' health is to be protected. Although botanicals and their preparations are regulated at EU level, at least in part, there is still considerable discretion at national level, and Member States may choose to classify a product either as a food supplement or as a drug. Accurate data concerning the finished products and the plant used as the starting point are of major importance if risks and safety are to be properly assessed, but in addition standardized criteria for herbal preparation must be laid down and respected by researchers and manufacturers. Physiologically active as well as potentially toxic constituents need to be identified, and suitable analytical methods for their measurement specified, particularly in view of the increasing incidence of economically motivated adulteration of herbal raw materials and extracts. It remains the duty of food operators to keep up with the scientific literature and to provide sufficient information to enable the adaptation of specifications, sampling schemes and analytical methods to a fast-changing environment.

  11. SOWFA Super-Controller: A High-Fidelity Tool for Evaluating Wind Plant Control Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, P.; Gebraad, P.; van Wingerden, J. W.; Lee, S.; Churchfield, M.; Scholbrock, A.; Michalakes, J.; Johnson, K.; Moriarty, P.

    2013-01-01

    This paper presents a new tool for testing wind plant controllers in the Simulator for Offshore Wind Farm Applications (SOWFA). SOWFA is a high-fidelity simulator for the interaction between wind turbine dynamics and the fluid flow in a wind plant. The new super-controller testing environment in SOWFA allows for the implementation of the majority of the wind plant control strategies proposed in the literature.

  12. Reconfigurable Control of a Ship Propulsion Plant

    DEFF Research Database (Denmark)

    Blanke, M.; Izadi-Zamanabadi, Roozbeh

    1998-01-01

    Fault-tolerant control combines fault detection and isolation techniques with supervisory control, to achieve the autonomous accommodation of faults before they develop into failures. While fault detection and isolation (FDI) methods have matured during the past decade, the extension to fault......-tolerant control is a fairly new area. Thise paper presents a ship propulsion system as a benchmark that should be useful as a platform for the development of new ideas and a comparison of methods. The benchmark has two main elements. One is the development of efficient FDI algorithms, and the other...... is the analysis and implementation of autonomous fault accommodation. A benchmark kit can be obtained from the authors....

  13. Modeling, simulation, and control of an extraterrestrial oxygen production plant

    Science.gov (United States)

    Schooley, L.; Cellier, F.; Zeigler, B.; Doser, A.; Farrenkopf, G.

    1991-01-01

    The immediate objective is the development of a new methodology for simulation of process plants used to produce oxygen and/or other useful materials from local planetary resources. Computer communication, artificial intelligence, smart sensors, and distributed control algorithms are being developed and implemented so that the simulation or an actual plant can be controlled from a remote location. The ultimate result of this research will provide the capability for teleoperation of such process plants which may be located on Mars, Luna, an asteroid, or other objects in space. A very useful near-term result will be the creation of an interactive design tool, which can be used to create and optimize the process/plant design and the control strategy. This will also provide a vivid, graphic demonstration mechanism to convey the results of other researchers to the sponsor.

  14. Power plant instrumentation and control handbook a guide to thermal power plants

    CERN Document Server

    Basu, Swapan

    2014-01-01

    The book discusses instrumentation and control in modern fossil fuel power plants, with an emphasis on selecting the most appropriate systems subject to constraints engineers have for their projects. It provides all the plant process and design details, including specification sheets and standards currently followed in the plant. Among the unique features of the book are the inclusion of control loop strategies and BMS/FSSS step by step logic, coverage of analytical instruments and technologies for pollution and energy savings, and coverage of the trends toward filed bus systems and integratio

  15. Artificial Intelligence Based Alum Dosage Control in Water Treatment Plant

    Directory of Open Access Journals (Sweden)

    P Poongodi

    2013-08-01

    Full Text Available Supplying good quality of drinking water is a challenging task during the rainy season and floods. During this period water becomes highly polluted with suspended solids which increase the water turbidity. Alum is used to reduce the turbidity of the water. Typically in water treatment plants alum dosage is decided by the Jar test and the desired alum dosage is added manually. This research proposes an automatic alum dosage mixing process. The alum dosage is controlled by an intelligent controller which consists of a dosage predictor, an inverse model of the dosage pump and a Pulse Width Modulation (PWM controller. The optimal alum dosage is predicted by the dosage predictor. The PWM controller controls the flow rate of the alum dosing pump. This proposed method has been implemented in a laboratory based water treatment plant and it ensures the automation in water treatment plant to supply good quality drinking water.

  16. Next Generation Nuclear Plant Resilient Control System Functional Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lynne M. Stevens

    2010-07-01

    Control Systems and their associated instrumentation must meet reliability, availability, maintainability, and resiliency criteria in order for high temperature gas-cooled reactors (HTGRs) to be economically competitive. Research, perhaps requiring several years, may be needed to develop control systems to support plant availability and resiliency. This report functionally analyzes the gaps between traditional and resilient control systems as applicable to HTGRs, which includes the Next Generation Nuclear Plant; defines resilient controls; assesses the current state of both traditional and resilient control systems; and documents the functional gaps existing between these two controls approaches as applicable to HTGRs. This report supports the development of an overall strategy for applying resilient controls to HTGRs by showing that control systems with adequate levels of resilience perform at higher levels, respond more quickly to disturbances, increase operational efficiency, and increase public protection.

  17. Expert System Control of Plant Growth in an Enclosed Space

    Science.gov (United States)

    May, George; Lanoue, Mark; Bathel, Matthew; Ryan, Robert E.

    2008-01-01

    The Expert System is an enclosed, controlled environment for growing plants, which incorporates a computerized, knowledge-based software program that is designed to capture the knowledge, experience, and problem-solving skills of one or more human experts in a particular discipline. The Expert System is trained to analyze crop/plant status, to monitor the condition of the plants and the environment, and to adjust operational parameters to optimize the plant-growth process. This system is intended to provide a way to remotely control plant growth with little or no human intervention. More specifically, the term control implies an autonomous method for detecting plant states such as health (biomass) or stress and then for recommending and implementing cultivation and/or remediation to optimize plant growth and to minimize consumption of energy and nutrients. Because of difficulties associated with delivering energy and nutrients remotely, a key feature of this Expert System is its ability to minimize this effort and to achieve optimum growth while taking into account the diverse range of environmental considerations that exist in an enclosed environment. The plant-growth environment for the Expert System could be made from a variety of structures, including a greenhouse, an underground cavern, or another enclosed chamber. Imaging equipment positioned within or around the chamber provides spatially distributed crop/plant-growth information. Sensors mounted in the chamber provide data and information pertaining to environmental conditions that could affect plant development. Lamps in the growth environment structure supply illumination, and other additional equipment in the chamber supplies essential nutrients and chemicals.

  18. Microgrid Plant Control Design and Development

    Energy Technology Data Exchange (ETDEWEB)

    Wiegman, Herman; Baone, Chaitanya

    2017-08-14

    This report discusses the technical performance of the proposed microgrid at Potsdam, New York, and the enhanced microgrid controller platform. The test objectives were outlined by the DOE, and summary results and discussion are given for each objective. The findings show that the proposed Potsdam, NY microgrid would have a significant impact on the regional CO2 emissions, the amount of imported energy from the utility, and the resiliency of the critical loads. Additionally, the enhanced microgrid control system developed for this project was tested to be compliant with IEEE 1547 standards, and able to generate revenues to help offset energy costs by way of participation in ancillary services.

  19. Reconfigurable Control of a Ship Propulsion Plant

    DEFF Research Database (Denmark)

    Blanke, M.; Izadi-Zamanabadi, Roozbeh

    1998-01-01

    -tolerant control is a fairly new area. Thise paper presents a ship propulsion system as a benchmark that should be useful as a platform for the development of new ideas and a comparison of methods. The benchmark has two main elements. One is the development of efficient FDI algorithms, and the other...

  20. Plant-based strategies for mosquito control

    Science.gov (United States)

    Mosquitoes transmit some of the most devastating emerging infectious diseases of humans, domestic animals, and wildlife. Although vector control by use of chemical insecticides has played an important role in prevention and management of these diseases, their sustained use remains questionable due t...

  1. Control of triacylglycerol biosynthesis in plants

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-31

    Seeds of most species of the Umbelliferae (Apiaciae), Araliaceae, and Garryaceae families are characterized by their high content of the unusual C[sub 18] monounsaturated fatty acid petroselinic acid (18:l[Delta][sup 6cis]). Prior to a recent report of this lab, little was known of the biosynthetic origin of the cis[Delta][sup 6] double bond of petroselinic acid. Such knowledge may be of both biochemical and biotechnological significance. Because petroselinic acid is potentially the product of a novel desaturase, information regarding its synthesis may contribute to an understanding of fatty acid desaturation mechanisms in plants. Through chemical cleavage at its double bond, petroselinic acid can be used as a precursor of lauric acid (12:0), a component of detergents and surfactants, and adipic acid (6:0 dicarboxylic), the monomeric component of nylon 6,6. Therefore, the development of an agronomic source of an oil rich in petroselinic acid is of biotechnological interest. As such, studies of petroselinic acid biosynthesis may provide basic information required for any attempt to genetically engineer the production and accumulation of this fatty acid in an existing oilseed.

  2. Plant virus infections control stomatal development

    Science.gov (United States)

    Murray, Rose R.; Emblow, Mark S. M.; Hetherington, Alistair M.; Foster, Gary D.

    2016-01-01

    Stomata are important regulators of carbon dioxide uptake and transpirational water loss. They also represent points of vulnerability as bacterial and fungal pathogens utilise this natural opening as an entry portal, and thus have an increasingly complex relationship. Unlike the situation with bacterial and fungal pathogens, we know very little about the role of stomata in viral infection. Here we report findings showing that viral infection influences stomatal development in two susceptible host systems (Nicotiana tabacum with TMV (Tobacco mosaic virus), and Arabidopsis thaliana with TVCV (Turnip vein-clearing virus)), but not in resistant host systems (Nicotiana glutinosa and Chenopodium quinoa with TMV). Virus infected plants had significantly lower stomatal indices in systemic leaves of susceptible systems; N. tabacum 9.8% reduction and A. thaliana 12.3% reduction, but not in the resistant hosts. Stomatal density in systemic leaves was also significantly reduced in virus infected A. thaliana by 19.6% but not in N. tabacum or the resistant systems. In addition, transpiration rate was significantly reduced in TMV infected N. tabacum. PMID:27687773

  3. Plant virus infections control stomatal development

    Science.gov (United States)

    Murray, Rose R.; Emblow, Mark S. M.; Hetherington, Alistair M.; Foster, Gary D.

    2016-09-01

    Stomata are important regulators of carbon dioxide uptake and transpirational water loss. They also represent points of vulnerability as bacterial and fungal pathogens utilise this natural opening as an entry portal, and thus have an increasingly complex relationship. Unlike the situation with bacterial and fungal pathogens, we know very little about the role of stomata in viral infection. Here we report findings showing that viral infection influences stomatal development in two susceptible host systems (Nicotiana tabacum with TMV (Tobacco mosaic virus), and Arabidopsis thaliana with TVCV (Turnip vein-clearing virus)), but not in resistant host systems (Nicotiana glutinosa and Chenopodium quinoa with TMV). Virus infected plants had significantly lower stomatal indices in systemic leaves of susceptible systems; N. tabacum 9.8% reduction and A. thaliana 12.3% reduction, but not in the resistant hosts. Stomatal density in systemic leaves was also significantly reduced in virus infected A. thaliana by 19.6% but not in N. tabacum or the resistant systems. In addition, transpiration rate was significantly reduced in TMV infected N. tabacum.

  4. Rapid Control Prototyping Plataform for Didactic Plant Motor DC

    Directory of Open Access Journals (Sweden)

    Cristian Bazán-Orobio

    2013-06-01

    Full Text Available In this paper a design, implementation and validation of a Rapid Control Prototype platform for a plant based on a DC motor is proposed. This low-cost prototype provides of an electronic card (with a motor DC and sensors manipulated by PC with free software tools using Linux, Scilab / Scicos and RTAI-Lab. This RCP System allows developing speed -position control trainings by using different types of PID industrial controllers with anti – wind up and bump less transfer schemes. We develop a speed control application structured in four steps: identification, controller design, simulation and real time control, where there are pedagogical advantages of a platform that not only allows simulation but also real-time control of a plant.

  5. Highlights of the GURI hydroelectric plant computer control system

    Energy Technology Data Exchange (ETDEWEB)

    Dal Monte, R.; Banakar, H.; Hoffman, R.; Lebeau, M.; Schroeder, R.

    1988-07-01

    The GURI power plant on the Caroni river in Venezuela has 20 generating units with a total capacity of 10,000 MW, the largest currently operating in the world. The GURI Computer Control System (GCS) provides for comprehensive operation management of the entire power plant and the adjacent switchyards. This article describes some highlights of the functions of the state-of-the-art system. The topics considered include the operating modes of the remote terminal units (RTUs), automatic start/stop of generating units, RTU closed-loop control, automatic generation and voltage control, unit commitment, operator training stimulator, and maintenance management.

  6. Reactive power control with CHP plants - A demonstration

    DEFF Research Database (Denmark)

    Nyeng, Preben; Østergaard, Jacob; Andersen, Claus A.;

    2010-01-01

    power rating of 7.3 MW on two synchronous generators. A closed-loop control is implemented, that remote controls the CHP plant to achieve a certain reactive power flow in a near-by substation. The solution communicates with the grid operator’s existing SCADA system to obtain measurements from...

  7. Fuzzy control applied to nuclear power plant pressurizer system

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Mauro V.; Almeida, Jose C.S., E-mail: mvitor@ien.gov.b, E-mail: jcsa@ien.gov.b [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2011-07-01

    In a pressurized water reactor (PWR) nuclear power plants (NPPs) the pressure control in the primary loop is very important for keeping the reactor in a safety condition and improve the generation process efficiency. The main component responsible for this task is the pressurizer. The pressurizer pressure control system (PPCS) utilizes heaters and spray valves to maintain the pressure within an operating band during steady state conditions, and limits the pressure changes, during transient conditions. Relief and safety valves provide overpressure protection for the reactor coolant system (RCS) to ensure system integrity. Various protective reactor trips are generated if the system parameters exceed safe bounds. Historically, a proportional-integral derivative (PID) controller is used in PWRs to keep the pressure in the set point, during those operation conditions. The purpose of this study has two main goals: first is to develop a pressurizer model based on artificial neural networks (ANNs); second is to develop a fuzzy controller for the PWR pressurizer pressure, and compare its performance with the P controller. Data from a simulator PWR plant was used to test the ANN and the controllers as well. The reference simulator is a Westinghouse 3-loop PWR plant with a total thermal output of 2785 MWth. The simulation results show that the pressurizer ANN model response are in reasonable agreement with the simulated power plant, and the fuzzy controller built in this study has better performance compared to the P controller. (author)

  8. The advanced main control console for next japanese PWR plants

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiya, A. [Hokkaido Electric Power Co., Inc., Sapporo (Japan); Ito, K. [Mitsubishi Heavy Industries, Ltd., Nuclear Energy Systems Engineering Center, Yokohama (Japan); Yokoyama, M. [Mitsubishi Electric Corporation, Energy and Industrial Systems Center, Kobe (Japan)

    2001-07-01

    The purpose of the improvement of main control room designing in a nuclear power plant is to reduce operators' workload and potential human errors by offering a better working environment where operators can maximize their abilities. In order to satisfy such requirements, the design of main control board applied to Japanese Pressurized Water Reactor (PWR) type nuclear power plant has been continuously modified and improved. the Japanese Pressurized Water Reactor (PWR) Utilities (Electric Power Companies) and Mitsubishi Group have developed an advanced main control board (console) reflecting on the study of human factors, as well as using a state of the art electronics technology. In this report, we would like to introduce the configuration and features of the Advanced Main Control Console for the practical application to the next generation PWR type nuclear power plants including TOMARI No.3 Unit of Hokkaido Electric Power Co., Inc. (author)

  9. Transcription regulation by CHD proteins to control plant development

    Directory of Open Access Journals (Sweden)

    Yongfeng eHu

    2014-05-01

    Full Text Available CHD (Chromodomain-Helicase-DNA binding proteins have been characterized in various species as important transcription regulators by their chromatin remodeling activity. However, in plant the function of these proteins has hardly been analyzed before except that Arabidopsis PICKLE and rice CHR729 are identified to play critical roles in the regulation of series of genes involved in developmental or stress responding process. In this review we focus on how plant CHD proteins regulate gene expression and the role of these proteins in controlling plant development and stress response.

  10. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    Directory of Open Access Journals (Sweden)

    Marija Ravlić

    2014-06-01

    Full Text Available Biological control is the use of live beneficial organisms and products of their metabolism in the pests control. Plant pathogens can be used for weed control in three different ways: as classical, conservation and augmentative (inoculative and inundated biological control. Inundated biological control involves the use of bioherbicides (mycoherbicides or artificial breeding of pathogens and application in specific stages of crops and weeds. Biological control of weeds can be used where chemical herbicides are not allowed, if resistant weed species are present or in the integrated pest management against weeds with reduced herbicides doses and other non-chemical measures, but it has certain limitations and disadvantages.

  11. Performance limitations for networked control systems with plant uncertainty

    Science.gov (United States)

    Chi, Ming; Guan, Zhi-Hong; Cheng, Xin-Ming; Yuan, Fu-Shun

    2016-04-01

    There has recently been significant interest in performance study for networked control systems with communication constraints. But the existing work mainly assumes that the plant has an exact model. The goal of this paper is to investigate the optimal tracking performance for networked control system in the presence of plant uncertainty. The plant under consideration is assumed to be non-minimum phase and unstable, while the two-parameter controller is employed and the integral square criterion is adopted to measure the tracking error. And we formulate the uncertainty by utilising stochastic embedding. The explicit expression of the tracking performance has been obtained. The results show that the network communication noise and the model uncertainty, as well as the unstable poles and non-minimum phase zeros, can worsen the tracking performance.

  12. Integrated control algorithms for plant environment in greenhouse

    Science.gov (United States)

    Zhang, Kanyu; Deng, Lujuan; Gong, Youmin; Wang, Shengxue

    2003-09-01

    In this paper a survey of plant environment control in artificial greenhouse was put forward for discussing the future development. Firstly, plant environment control started with the closed loop control of air temperature in greenhouse. With the emergence of higher property computer, the adaptive control algorithm and system identification were integrated into the control system. As adaptation control is more depending on observation of variables by sensors and yet many variables are unobservable or difficult to observe, especially for observation of crop growth status, so model-based control algorithm were developed. In order to evade modeling difficulty, one method is predigesting the models and the other method is utilizing fuzzy logic and neural network technology that realize the models by the black box and gray box theory. Studies on control method of plant environment in greenhouse by means of expert system (ES) and artificial intelligence (AI) have been initiated and developed. Nowadays, the research of greenhouse environment control focus on energy saving, optimal economic profit, enviornment protection and continualy develop.

  13. Control techniques for invasive alien plants

    Directory of Open Access Journals (Sweden)

    Michele de Sá Dechoum

    2013-03-01

    Full Text Available Invasive alien species are recognized as a major threat to the conservation of biodiversity. These species should be managed based on local and regional environmental conditions. Control techniques were tested for ten invasive species in Santa Catarina State: the trees Casuarina equisetifolia, Hovenia dulcis, Psidium guajava, Syzygium cumini, and Terminalia catappa, and shrubs and herbs Rubus fruticosus, Furcraea foetida, Hedychium coronarium, Impatiens walleriana, and Tradescantia zebrina. Treatments applied for trees were cut stump, frill and girdling or ring-barking followed by herbicide application, while the other species were treated with foliar spray, application of herbicide on the root system, cut stump and herbicide injection. The active ingredients tested were Triclopyr, Glyphosate, and the combination of Triclopyr + Fluroxipyr in concentrations from 2 to 6%, according to the species. The cut stump method was efficient for all of the woody species, while ring-barking and frilling followed by herbicide application and basal bark application resulted in different levels of efficiency for the species tested. The most efficient method for herbs and shrubs was foliar spray, and the least efficient methods were cut stump and herbicide injection.

  14. Joint excitation and reactive power control in thermal power plant

    Directory of Open Access Journals (Sweden)

    Dragosavac Jasna

    2013-01-01

    Full Text Available The coordinated voltage and reactive power controller, designed for the thermal power plant, is presented in the paper. A brief explanation of the need for such device is given and justification for commissioning of such equipment is outlined. After short description of the theoretical background of the proposed control design, the achieved features of the commissioned equipment are fully given. Achieved performances are illustrated by recorded reactive power and bus voltage responses after commissioning of the described equipment into the largest thermal power plant in Serbia. As it can be seen in presented records, all design targets are met.

  15. Optimal control of a waste water cleaning plant

    Directory of Open Access Journals (Sweden)

    Ellina V. Grigorieva

    2010-09-01

    Full Text Available In this work, a model of a waste water treatment plant is investigated. The model is described by a nonlinear system of two differential equations with one bounded control. An optimal control problem of minimizing concentration of the polluted water at the terminal time T is stated and solved analytically with the use of the Pontryagin Maximum Principle. Dependence of the optimal solution on the initial conditions is established. Computer simulations of a model of an industrial waste water treatment plant show the advantage of using our optimal strategy. Possible applications are discussed.

  16. Health-aware Model Predictive Control of Pasteurization Plant

    Science.gov (United States)

    Karimi Pour, Fatemeh; Puig, Vicenç; Ocampo-Martinez, Carlos

    2017-01-01

    In order to optimize the trade-off between components life and energy consumption, the integration of a system health management and control modules is required. This paper proposes the integration of model predictive control (MPC) with a fatigue estimation approach that minimizes the damage of the components of a pasteurization plant. The fatigue estimation is assessed with the rainflow counting algorithm. Using data from this algorithm, a simplified model that characterizes the health of the system is developed and integrated with MPC. The MPC controller objective is modified by adding an extra criterion that takes into account the accumulated damage. But, a steady-state offset is created by adding this extra criterion. Finally, by including an integral action in the MPC controller, the steady-state error for regulation purpose is eliminated. The proposed control scheme is validated in simulation using a simulator of a utility-scale pasteurization plant.

  17. Z Number Based Fuzzy Inference System for Dynamic Plant Control

    Directory of Open Access Journals (Sweden)

    Rahib H. Abiyev

    2016-01-01

    Full Text Available Frequently the reliabilities of the linguistic values of the variables in the rule base are becoming important in the modeling of fuzzy systems. Taking into consideration the reliability degree of the fuzzy values of variables of the rules the design of inference mechanism acquires importance. For this purpose, Z number based fuzzy rules that include constraint and reliability degrees of information are constructed. Fuzzy rule interpolation is presented for designing of an inference engine of fuzzy rule-based system. The mathematical background of the fuzzy inference system based on interpolative mechanism is developed. Based on interpolative inference process Z number based fuzzy controller for control of dynamic plant has been designed. The transient response characteristic of designed controller is compared with the transient response characteristic of the conventional fuzzy controller. The obtained comparative results demonstrate the suitability of designed system in control of dynamic plants.

  18. Augmenting Plant Immune Responses and Biological Control by Microbial Determinants

    Directory of Open Access Journals (Sweden)

    Sang Moo Lee

    2015-09-01

    Full Text Available Plant have developed sophisticated defence mechanisms against microbial pathogens. The recent accumulated information allow us to understand the nature of plant immune responses followed by recognition of microbial factors/determinants through cutting-edge genomics and multi-omics techniques. However, the practical approaches to sustain plant health using enhancement of plant immunity is yet to be fully appreciated. Here, we overviewed the general concept and representative examples on the plant immunity. The fungal, bacterial, and viral determinants that was previously reported as the triggers of plant immune responses are introduced and described as the potential protocol of biological control. Specifically, the role of chitin, glucan, lipopolysaccharides/extracellular polysaccharides, microbe/pathogen-associated molecular pattern, antibiotics, mimic-phytohormones, N-acyl homoserine lactone, harpin, vitamins, and volatile organic compounds are considered. We hope that this review stimulates scientific community and farmers to broaden their knowledge on the microbial determinant-based biological control and to apply the technology on the integrated pest management program.

  19. Genetic and epigenetic control of plant heat responses

    Directory of Open Access Journals (Sweden)

    Junzhong eLiu

    2015-04-01

    Full Text Available Plants have evolved sophisticated genetic and epigenetic regulatory systems to respond quickly to unfavorable environmental conditions such as heat, cold, drought, and pathogen infections. In particular, heat greatly affects plant growth and development, immunity and circadian rhythm, and poses a serious threat to the global food supply. According to temperatures exposing, heat can be usually classified as warm ambient temperature (about 22-27℃, high temperature (27-30℃ and extremely high temperature (37-42℃, also known as heat stress for the model plant Arabidopsis thaliana. The genetic mechanisms of plant responses to heat have been well studied, mainly focusing on elevated ambient temperature-mediated morphological acclimation and acceleration of flowering, modulation of plant immunity and circadian clock by high temperatures, and thermotolerance to heat stress. Recently, great progress has been achieved on epigenetic regulation of heat responses, including DNA methylation, histone modifications, histone variants, ATP-dependent chromatin remodeling, histone chaperones, small RNAs, long non-coding RNAs and other undefined epigenetic mechanisms. These epigenetic modifications regulate the expression of heat-responsive genes and function to prevent heat-related damage. This review focuses on recent progresses regarding the genetic and epigenetic control of heat responses in plants, and pays more attention to the role of the major epigenetic mechanisms in plant heat responses. Further research perspectives are also discussed.

  20. Control of meiotic recombination frequency in plant genomes.

    Science.gov (United States)

    Henderson, Ian R

    2012-11-01

    Sexual eukaryotes reproduce via the meiotic cell division, where ploidy is halved and homologous chromosomes undergo reciprocal genetic exchange, termed crossover (CO). CO frequency has a profound effect on patterns of genetic variation and species evolution. Relative CO rates vary extensively both within and between plant genomes. Plant genome size varies by over 1000-fold, largely due to differential expansion of repetitive sequences, and increased genome size is associated with reduced CO frequency. Gene versus repeat sequences associate with distinct chromatin modifications, and evidence from plant genomes indicates that this epigenetic information influences CO patterns. This is consistent with data from diverse eukaryotes that demonstrate the importance of chromatin structure for control of meiotic recombination. In this review I will discuss CO frequency patterns in plant genomes and recent advances in understanding recombination distributions.

  1. The Plant Ontology Database: A Community Resource for Plant Structure and Developmental Stages Controlled Vocabulary and Annotations

    Science.gov (United States)

    The Plant Ontology Consortium (POC, http://www.plantontology.org) is a collaborative effort among model plant genome databases and plant researchers that aims to create, maintain and facilitate the use of a controlled vocabulary(ontology) for plants. The ontology allows users to ascribe attributes o...

  2. Design and control of integrated styrene aniline production plant

    NARCIS (Netherlands)

    Partenie, O.; Van der Last, V.; Sorin Bildea, C.; Altimari, P.

    2009-01-01

    This paper illustrates the operational difficulties arising from simultaneously performing exothermic and endothermic reactions, and demonstrates that a plant can be built and safely operated by integrating the design and plantwide control issues. The behaviour of reactor – separation – recycle

  3. Impacto del ajuste por inflación financiero en la gestión empresarial

    Directory of Open Access Journals (Sweden)

    Oda Hilda Gómez de Angulo

    2009-01-01

    Full Text Available La inflación es un fenómeno económico que afecta la situación financiera de las organizaciones, por lo que existe la Declaración de Principios de Contabilidad No. 10 (DPC-10 que establece las normas para efectuar el ajuste por inflación a los estados financieros. Con el propósito de conocer el impacto de este ajuste, se seleccionaron dos empresas que realizan actividades diferentes. Se efectuó una revisión bibliográfica y documental de la DPC-10 y, con base a los informes al cierre de cada ejercicio económico de las empresas objeto de estudio, se recopilaron y prepararon los datos en una misma unidad de medida para efectos de comparación, análisis e interpretación. Los resultados obtenidos indican que en la empresa regida por la Comisión Nacional de Valores se justifica el ajuste por inflación financiero debido a la naturaleza de la estructura financiera y a que la toma de decisiones administrativas y legales se realiza con base a esta información; mientras que en la institución regida por la Superintendencia de Cajas de Ahorro no se justifica la presentación del ajuste por inflación financiero, ya que no aporta ningún valor agregado a la organización y la toma de decisiones se realiza con base a los estados financieros históricos.

  4. Hacia un sistema armonizado de ajuste de la dosis en un tratamiento fitosanitario

    OpenAIRE

    Camp, Ferran; Solanelles Batlle, Francesc; Garcia, F.; Escolà i Agustí, Alexandre; Sanz Cortiella, Ricardo; Rosell Polo, Joan Ramon; Planas de Martí, Santiago

    2012-01-01

    Tradicionalmente, las dosis indicadas en las etiquetas de los envases de los productos fitosanitarios se expresan en función de uno, o muy pocos, de los factores que intervienen en toda aplicación. El camino hacia la racionalización de las dosis pasa por la utilización de un sistema que integre el mayor número de condicionantes permitiendo así el ajuste de la dosis a las condiciones concretas de cada tratamiento.

  5. Desempenho dos ajustes do Trauma and Injury Severity Score (TRISS: revisão integrativa

    Directory of Open Access Journals (Sweden)

    Cristiane de Alencar Domingues

    2015-12-01

    Full Text Available RESUMO Objetivo identificar estudos que realizaram ajustes na equação do Trauma and InjurySeverity Score (TRISS e compararam a capacidade discriminatória da equação modificada com a original. Método Revisão integrativa de pesquisas publicadas entre 1990 e 2014 nas bases de dados LILACS, MEDLINE, PubMed e SciELO utilizando-se a palavra TRISS. Resultados foram incluídos 32 estudos na revisão. Dos 67 ajustes de equações do TRISS identificados, 35 (52,2% resultaram em melhora na acurácia do índice para predizer a probabilidade de sobrevida de vítimas de trauma. Ajustes dos coeficientes do TRISS à população de estudo foram frequentes, mas nem sempre melhoraram a capacidade preditiva dos modelos analisados. A substituição de variáveis fisiológicas do Revised Trauma Score (RTS e modificações do Injury Severity Score (ISS na equação original tiveram desempenho variado. A mudança na forma de inclusão da idade na equação, assim como a inserção do gênero, comorbidades e mecanismo do trauma apresentaram tendência de melhora do desempenho do TRISS. Conclusão Diferentes propostas de ajustes no TRISS foram identificadas nesta revisão e indicaram, principalmente, fragilidades do RTS no modelo original e necessidade de alteração da forma de inclusão da idade na equação para melhora da capacidade preditiva do índice.

  6. Silicon control of bacterial and viral diseases in plants

    Directory of Open Access Journals (Sweden)

    Sakr Nachaat

    2016-12-01

    Full Text Available Silicon plays an important role in providing tolerance to various abiotic stresses and augmenting plant resistance against diseases. However, there is a paucity of reports about the effect of silicon on bacterial and viral pathogens of plants. In general, the effect of silicon on plant resistance against bacterial diseases is considered to be due to either physical defense or increased biochemical defense. In this study, the interaction between silicon foliar or soil-treatments and reduced bacterial and viral severity was reviewed. The current review explains the agricultural importance of silicon in plants, refers to the control of bacterial pathogens in different crop plants by silicon application, and underlines the different mechanisms of silicon-enhanced resistance. A section about the effect of silicon in decreasing viral disease intensity was highlighted. By combining the data presented in this study, a better comprehension of the complex interaction between silicon foliar- or soil-applications and bacterial and viral plant diseases could be achieved.

  7. ¿Existe rigidez en el ajuste del empleo en Chile?

    Directory of Open Access Journals (Sweden)

    Jorge Dresdner

    2017-01-01

    Full Text Available Antecedentes: Estudiamos c mo el nivel de empleo agregado se ajust en la eco- nom a chilena, posterior a la llamada crisis asi tica. Contrastamos distintas hi- p tesis que se han esgrimido en el debate p blico, y que no han sido probadas formalmente, sobre las razones por las cuales el nivel de empleo tard tanto tiempo en recuperar los niveles precrisis. M todos: Especi camos y estimamos un modelo de vectores autorregresivos con series de tiempo para el trimestre 1995.1-2007.4 y aplicamos el m todo de Jo- hansen para identi car vectores de cointegraci n. Resultados: Estimamos un vector de cointegraci n que representa la funci n de demanda laboral. Realizamos las siguientes pruebas de hip tesis sobre esta fun- ci n: homogeneidad de grado cero en precios, elasticidad producto de la de- manda unitaria; quiebre estructural en el intercepto de esta funci n; cambio en la elasticidad producto de la demanda laboral de largo plazo entre subperiodos y existencia de costos de ajuste. Conclusiones: Inestabilidad en la elasticidad demanda del ingreso en la funci n de demanda por trabajo en Chile posterior a la crisis asi tica, pero no en la direc- ci n sugerida por el debate previo. Adicionalmente, el factor que contribuy en forma m s decisiva a la lenta recuperaci n del empleo posterior a la crisis fue el costo de ajuste presentes en la econom a chilena.

  8. Análise dos ajustes insulinoterápicos realizados a partir de dois esquemas de monitorização domiciliar em pacientes com diabetes mellitus do tipo 1 Análisis de los ajustes insulinoterápicos realizados a partir de dos esquemas de monitorización domiciliaria en pacientes con diabetes mellitus del tipo 1 Frequency and insulin adjustments among patients with type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Sonia Aurora Alves Grossi

    2006-12-01

    Full Text Available OBJETIVOS: Identificar a freqüência e magnitude nos ajustes das doses de insulina a partir de dois esquemas de monitorização domiciliar sangüíneo e urinário em pacientes com diabetes mellitus do tipo1 e avaliar a efetividade dos ajustes no controle metabólico. MÉTODOS: Amostra de 25 pacientes dividida em dois grupos. Osdo Grupo A realizaram monitorização domiciliar da glicemia capilar e osdo Grupo B, monitorização domiciliar da glicosúria, conforme esquemas preconizados. Estes esquemas possibilitaram construção de perfis e de ajustes insulinoterápicos. RESULTADOS: Houve 204 possibilidades de ajustes no Grupo A e 87 no Grupo B. Com relação às doses de insulina NPH matutina, no Grupo A foram implementados 95 (46,57%ajustes e no Grupo B 30 (34,48% (p= 0,03715. Os ajustes nas doses de insulina regular feitas antes do jantar também foram maiores no Grupo A ,22 (10,84%do que no Grupo B, 3 (3,45% (p=0,02852. O Grupo A, apresentou-se com melhor controle metabólico (HbA1c=10,17% quando comparado ao Grupo B (HbA1c=12,31%. CONCLUSÕES: A monitorização domiciliar da glicemia, possibilitou maior número de ajustes, maior número de aplicações e melhor controle metabólico.OBJETIVOS: Identificar la frecuencia y magnitud en los ajustes de las dosis de insulina a partir de dos esquemas de monitorización domiciliaria sanguíneo y urinario en pacientes con diabetes mellitus del tipo1 y evaluar la efectividad de los ajustes en el control metabólico. MÉTODOS: muestra de 25 pacientes dividida en dos grupos. Losdel Grupo A realizaron monitorización domiciliaria de la glicemia capilar y losdel Grupo B, monitorización domiciliaria de la glicosuria, conforme esquemas establecidos. Estos esquemas posibilitaron la construcción de perfiles y de ajustes insulinoterápicos. RESULTADOS: Hubo 204 posibilidades de ajustes en el Grupo A y 87 en el Grupo B. Con relación a las dosis de insulina NPH matutina, en el Grupo A fueron implementados 95

  9. Introducing Model Predictive Control for Improving Power Plant Portfolio Performance

    DEFF Research Database (Denmark)

    Edlund, Kristian Skjoldborg; Bendtsen, Jan Dimon; Børresen, Simon

    2008-01-01

    This paper introduces a model predictive control (MPC) approach for construction of a controller for balancing the power generation against consumption in a power system. The objective of the controller is to coordinate a portfolio consisting of multiple power plant units in the effort to perform...... reference tracking and disturbance rejection in an economically optimal way. The performance function is chosen as a mixture of the `1-norm and a linear weighting to model the economics of the system. Simulations show a significant improvement of the performance of the MPC compared to the current...

  10. Herbivores and nutrients control grassland plant diversity via light limitation

    Science.gov (United States)

    Borer, Elizabeth T.; Seabloom, Eric W.; Gruner, Daniel S.; Harpole, W. Stanley; Hillebrand, Helmut; Lind, Eric M.; Alder, Peter B.; Alberti, Juan; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori; Blumenthal, Dana; Brown, Cynthia S.; Brudvig, Lars A.; Buckley, Yvonne M.; Cadotte, Marc; Chu, Cheng-Jin; Cleland, Elsa E.; Crawley, Michael J.; Daleo, Pedro; Damschen, Ellen Ingman; Davies, Kendi F.; DeCrappeo, Nicole M.; Du, Guozhen; Firn, Jennifer; Hautier, Yann; Heckman, Robert W.; Hector, Andy; HilleRisLambers, Janneke; Iribarne, Oscar; Klein, Julia A.; Knops, Johannes M.H.; La Pierre, Kimberly J.; Leakey, Andrew D.B.; Li, Wei; MacDougall, Andrew S.; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Mortensen, Brent; O'Halloran, Lydia R.; Orrock, John L.; Pascual, Jesús; Prober, Suzanne M.; Pyke, David A.; Risch, Anita C.; Schuetz, Martin; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren L.; Williams, Ryan J.; Wragg, Peter D.; Wright, Justin P.; Yang, Louie H.

    2014-01-01

    Human alterations to nutrient cycles and herbivore communities are affecting global biodiversity dramatically. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  11. Controlling pH in a Precipitation Plant

    Directory of Open Access Journals (Sweden)

    Kjell Støle-Hansen

    1997-10-01

    Full Text Available This paper deals with pH control in a precipitation and dissolution process. The process is a part of the electrolyte purification plant at Falconbridge Nikkelverk in Kristiansand, Norway. The process including the present strategy for pH control are presented, and experienced weaknesses with this strategy are described. A rigorous dynamic model of the process is briefly summarized. This model was developed in earlier work with the purpose of being a tool for control design. Because of the precipitation in form of hydroxides and the limited dissolution rate of nickel carbonate, the process is approximately linear in pH. Therefore, an alternative strategy for pH control based on adding derivative and feed forward action is suggested. The alternative control strategy is by simulations shown to give severe improvements in performance. The robustness of the proposed controller is briefly analysed.

  12. Can lemmings control the expansion of woody plants on tundra?

    Science.gov (United States)

    Oksanen, Lauri; Oksanen, Tarja; Olofsson, Johan; Virtanen, Risto; Hoset, Katrine; Tuomi, Maria; Kyrö, Kukka

    2013-04-01

    results show that edibility plays a relatively small role for the vulnerability of woody plants to lemming impacts. As long as the plants are relatively small, like the evergreens were on our plots (the dominating species was the lingonberry, Vaccinium vitis-ideaea), they are mowed down by lemmings in outbreak years. The potential of lemmings to control the expansion of woody plants is thus likely to depend on the size of the seedlings of trees and shrubs and, therefore, on the frequency of lemming outbreaks

  13. Mechanisms of developmentally controlled cell death in plants.

    Science.gov (United States)

    Van Durme, Matthias; Nowack, Moritz K

    2016-02-01

    During plant development various forms of programmed cell death (PCD) are implemented by a number of cell types as inherent part of their differentiation programmes. Differentiation-induced developmental PCD is gradually prepared in concert with the other cell differentiation processes. As precocious or delayed PCD can have detrimental consequences for plant development, the actual execution of PCD has to be tightly controlled. Once triggered, PCD is irrevocably and rapidly executed accompanied by the breakdown of cellular compartments. In most developmental PCD forms, cell death is followed by cell corpse clearance. Devoid of phagocytic mechanisms, dying plant cells have to prepare their own demise in a cell-autonomous fashion before their deaths, ensuring the completion of cell clearance post mortem. Depending on the cell type, cell clearance can be complete or rather selective, and persistent corpses of particular cells accomplish vital functions in the plant body. The present review attempts to give an update on the molecular mechanisms that coordinate differentiation-induced PCD as vital part of plant development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Increasing flexibility of coal power plant by control system modifications

    Directory of Open Access Journals (Sweden)

    Marušić Ante

    2016-01-01

    Full Text Available Expanding implementation of intermittent renewable energy sources has already started to change the role of thermal power plants in energy systems across Europe. Traditionally base load plants are now forced to operate as peaking plants. A familiar transition in upcoming years is expected in Croatia and coal power plant operators are preparing accordingly. To evaluate cycling capabilities and control system operation for flexible operation of selected 210 MW coal plant, series of tests with different load gradients were performed and results were thoroughly analyzed. Two possible “bottlenecks” are identified, thermal stress in superheater header, and achievable ramping rate considering operational limitations of coal feeders, firing system and evaporator dynamics. Several unexpected readings were observed, usually caused by malfunctioning sensors and equipment, resulting in unexpected oscillations of superheated steam temperature. Based on superheater geometry and experimental data, maximal steam temperature gradient during ramping was evaluated. Since thermal stress was well inside the safety margins, the simulation model of the whole boiler was used to evaluate achievable ramping on electric side.

  15. Simulation model for plant growth in controlled environment systems

    Science.gov (United States)

    Raper, C. D., Jr.; Wann, M.

    1986-01-01

    The role of the mathematical model is to relate the individual processes to environmental conditions and the behavior of the whole plant. Using the controlled-environment facilities of the phytotron at North Carolina State University for experimentation at the whole-plant level and methods for handling complex models, researchers developed a plant growth model to describe the relationships between hierarchial levels of the crop production system. The fundamental processes that are considered are: (1) interception of photosynthetically active radiation by leaves, (2) absorption of photosynthetically active radiation, (3) photosynthetic transformation of absorbed radiation into chemical energy of carbon bonding in solube carbohydrates in the leaves, (4) translocation between carbohydrate pools in leaves, stems, and roots, (5) flow of energy from carbohydrate pools for respiration, (6) flow from carbohydrate pools for growth, and (7) aging of tissues. These processes are described at the level of organ structure and of elementary function processes. The driving variables of incident photosynthetically active radiation and ambient temperature as inputs pertain to characterization at the whole-plant level. The output of the model is accumulated dry matter partitioned among leaves, stems, and roots; thus, the elementary processes clearly operate under the constraints of the plant structure which is itself the output of the model.

  16. Native plants for erosion control in urban river slopes

    Directory of Open Access Journals (Sweden)

    Virginia Alvarado

    2014-03-01

    Full Text Available Mechanical and structural erosion of soils is produced by the loss of the vegetal cover and the action of rain on unprotected surfaces. Raindrop impact, transport and sediment deposition leads to landslides and slope instability and soil loss. In Costa Rica, water bodies have been negatively impacted by urban development and both water resources and soils have become more vulnerable. This is the case of the Pirro river micro watershed where riverbed vegetation has been replaced by constructions producing erosion problems in its slopes. In order to evaluate how native plants favor sediment control and prevent this sediment from been deposited in the river, eight experimental plots were installed. Four treatments were established: A (Costus pulverulentus Presl, B (Heliconia tortuosa (Griggs Standl., C (Vetiveria zizanioides (L. Nash and D (control. Sediments were collected weekly during the rainy and transitional seasons. A clear relation between rainfall intensity and sediment production was determined, particularly for intensities higher than 50 mm h-1. Significant differences were also determined between the treatments and the efficiency order was B >A > C >D, with the native plants being the most efficient in terms of sediment control. The use of native plants is recommended for the management and rehabilitation of slopes near urban rivers due to their ecological value and their capability for sediment control.

  17. Screening for plant extracts to control potato late blight

    Institute of Scientific and Technical Information of China (English)

    WANG Shutong; HU Tongle; ZHANG Fengqiao; H.R.Forrer; CAO Keqiang

    2007-01-01

    Six extracts from plant material(Galla chinensis,Potentilla erecta,Rheum rhabarbarum,Salviae officinalis,Sophoraflavescens,and Terminalia chebula)were tested for controlling effects against the infection of Phytophthora infestans on detached potato leaves, seedlings, and tuber slices.On detached leaves,G.chinensis(2%),R.rhabarbarum(rhizome,2%)and S.flavescens(2%)extracts showed a significant control effect,with a control efficacy of 96.67%,G.chinensis was the best.On seedlings R.rhabarbarum(rhizome,2%)showed the best inhibiting effect,followed by S.flavescens(2%),T.chebula(1%),and G.chinensis(2%).The control efficacies were 91.67%,75.00%,70.24%,and 64.29%,respectively on the seventh day after inoculation.However,on potato slices,none of the plant extracts showed effective protection against infection and sporangia production by P.infestans.The reason was analyzed and the potential for developing a natural fungicide based on these plant materials was discussed.

  18. Control of Listeria monocytogenes in food production plants

    Directory of Open Access Journals (Sweden)

    Dimitrijević Mirjana

    2008-01-01

    Full Text Available L. monocytogenes has been established in different plants for the production of food, including dairy plants, abattoirs, plants for the processing of fish, as well as those for the production of ready-to-eat (RTE food and this fact is being considered as the primary mechanism of food contamination with this bacteria. There is also the factor of numerous and diverse contaminated production equipment, because it has certain parts that are inaccessible for the necessary cleaning and disinfection. The temperature, position, as well as the material of the work surface are also linked to the contamination of plants with this bacteria. Investigations carried out so far have helped toward the better understanding of the manner and time of contamination of food items in the course of the production process, but there are still unresolved problems, including most certainly the biggest one - the adherence of bacteria and the creation of a biofilm, when the bacteria is in that condition more resistant to so-called stress factors which are usually used in the food industry for the purpose of decontamination of the surfaces with which foods come into contact. The control of L. monocytogenes in food production plants is possible primarily by using an integrated programme, compatible with the systems Hazard Analysis Critical Control Point (HACCP and Good Hygiene Practice (GHP, necessary in the production of food that is safe for the consumer. Essentially, the control measures that can contribute to reducing the incidence of findings of L.monocytogenes in the finished product, as well as the reducing of the level of contamination with this bacteria are linked, on the one hand, with hygiene procedures in the production process, and, on the other, with the applied technological procedures.

  19. Understanding Plant-Soil Relationships Using Controlled Environment Facilities

    Science.gov (United States)

    Andersen, C. P.; Rygiewicz, P. T.

    1999-01-01

    Although soil is a component of terrestrial ecosystems, it is comprised of a complex web of interacting organisms, and therefore can be considered itself as an ecosystem. Soil microflora and fauna derive energy from plants and plant residues and serve important functions in maintaining soil physical and chemical properties, thereby affecting net primary productivity (NPP), and in the case of contained environments, the quality of the life support system. We have been using 3 controlled-environment facilities (CEF's) that incorporate different levels of soil biological complexity and environmental control, and differ in their resemblance to natural ecosystems, to study relationships among plant physiology, soil ecology, fluxes of minerals and nutrients, and overall ecosystem function. The simplest system utilizes growth chambers and specialized root chambers with organic-less media to study the physiology of plant-mycorrhizal associations. A second system incorporates natural soil in open-top chambers to study soil bacterial and fungal population response to stress. The most complex CEF incorporates reconstructed soil profiles in a ``constructed'' ecosystem, enabling close examination of the soil foodweb. Our results show that closed ecosystem research is important for understanding mechanisms of response to ecosystem stresses. In addition, responses observed at one level of biological complexity may not allow prediction of response at a different level of biological complexity. In closed life support systems, incorporating soil foodwebs will require less artificial manipulation to maintain system stability and sustainability.

  20. Emission control of gas effluents from geothermal power plants.

    Science.gov (United States)

    Axtmann, R C

    1975-01-01

    Geothermal steam at the world's five largest power plants contains from 0.15 to 30% noncondensable gases including CO(2), H(2)S, H(2), CH(4), N(2), H(3)BO(3), and NH(3). At four of the plants the gases are first separated from the steam and then discharged to the environment; at the fifth, the noncondensables exhaust directly to the atmosphere along with spent steam. Some CO(2) and sulfur emission rates rival those from fossil-fueled plants on a per megawatt-day basis. The ammonia and boron effluents can interfere with animal and plant life. The effects of sulfur (which emerges as H(2)S but may oxidize to SO(2)) on either ambient air quality or longterm human health are largely unknown. Most geothermal turbines are equipped with direct contact condensers which complicate emission control because they provide two or more pathways for the effluents to reach the environment. Use of direct contact condensers could permit efficient emission control if coupled to processes that produce saleable quantities of purified carbon dioxide and elemental sulfur.

  1. A Business Case for Nuclear Plant Control Room Modernization

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Ken [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lawrie, Sean [Idaho National Lab. (INL), Idaho Falls, ID (United States); Niedermuller, Josef M. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-06-01

    This paper presents a generic business case for implementation of technology that supports Control Room Modernization (CRM). The analysis presented in two forms; 1) a standalone technology upgrade, and 2) a technology upgrade that is built upon and incremental to a prior business case created for Mobile Work Packages (MWP). The business case contends that advanced communication and networking and analytical technologies will allow NPP to conduct control room operations with improved focus by reducing human factors and redundant manpower, and therefore operate with fewer errors. While some labor savings can be harvested in terms of overtime, the majority of savings are demonstrated as reduced time to take the plant off line and bring back on line in support of outages. The benefits are quantified to a rough order of magnitude that provides directional guidance to NPPs that are interested in developing a similar business case. This business case focuses on modernization of the operator control room and does not consider a complete overhaul and modernization of a plants instrument and control systems. While operators may be considering such an investment at their plants, the sizable capital investment required is not likely supported by a cost/benefit analysis alone. More likely, it is driven by obsolescence and reliability issues, and requires consideration of mechanical condition of plant systems, capital depreciation, financing, relicensing and overall viability of the plant asset over a 20-year horizon in a competitive market. Prior studies [REF] have indicated that such a modernization of plant I&C systems, alone or as part of a larger modernization effort, can yield very significant reductions in O&M costs. However, the depth of research and analysis required to develop a meaningful business case for a plant modernization effort is well beyond the scope of this study. While CRM as considered in this study can be easily integrated as part of grander plant

  2. Selection and Assessment of Plant Growth-Promoting Rhizobacteria for Biological Control of Multiple Plant Diseases.

    Science.gov (United States)

    Liu, Ke; Newman, Molli; McInroy, John A; Hu, Chia-Hui; Kloepper, Joseph W

    2017-08-01

    A study was designed to screen individual strains of plant growth-promoting rhizobacteria (PGPR) for broad-spectrum disease suppression in vitro and in planta. In a preliminary screen, 28 of 196 strains inhibited eight different tested pathogens in vitro. In a secondary screen, these 28 strains showed broad spectrum antagonistic activity to six different genera of pathogens, and 24 of the 28 strains produced five traits reported to be related to plant growth promotion, including nitrogen fixation, phosphate solubilization, indole-3-acetic acid production, siderophore production, and biofilm formation. In advanced screens, the 28 PGPR strains selected in vitro were tested in planta for biological control of multiple plant diseases including bacterial spot of tomato caused by Xanthomonas axonopodis pv. vesicatoria, bacterial speck of tomato caused by Pseudomonas syringae pv. tomato, damping-off of pepper caused by Rhizoctonia solani, and damping-off of cucumber caused by Pythium ultimum. In all, 5 of the 28 tested strains significantly reduced three of the four tested diseases, and another 19 strains showed biological control to two tested diseases. To understand the observed broad-spectrum biocontrol capacity, antiSMASH was used to predict secondary metabolite clusters of selected strains. Multiple gene clusters encoding for secondary metabolites, e.g., bacillibactin, bacilysin, and microcin, were detected in each strain. In conclusion, selected individual PGPR strains showed broad-spectrum biocontrol activity to multiple plant diseases.

  3. Development of abamectin loaded plant virus nanoparticles for efficacious plant parasitic nematode control.

    Science.gov (United States)

    Cao, Jing; Guenther, Richard H; Sit, Tim L; Lommel, Steven A; Opperman, Charles H; Willoughby, Julie A

    2015-05-13

    Plant parasitic nematodes are one of the world's major agricultural pests, causing in excess of $157 billion in worldwide crop damage annually. Abamectin (Abm) is a biological pesticide with a strong activity against a wide variety of plant parasitic nematodes. However, Abm's poor mobility in the soil compromises its nematicide performance because of the limited zone of protection surrounding the growing root system of the plant. In this study, we manipulated Abm's soil physical chemistry by encapsulating Abm within the Red clover necrotic mosaic virus (RCNMV) to produce a plant virus nanoparticle (PVN) delivery system for Abm. The transmission electron microscopic and dynamic light scattering characterization of Abm-loaded PVN (PVN(Abm)) indicated the resultant viral capsid integrity and morphology comparable to native RCNMV. In addition, the PVN(Abm) significantly increased Abm's soil mobility while enabling a controlled release strategy for Abm's bioavailability to nematodes. As a result, PVN(Abm) enlarged the zone of protection from Meloidogyne hapla root knot nematodes in the soil as compared to treating with free Abm molecules. Tomato seedlings treated with PVN(Abm) had healthier root growth and a reduction in root galling demonstrating the success of this delivery system for the increased efficacy of Abm to control nematode damage in crops.

  4. New computer-controlled precipitator at the Savannah River Plant

    Energy Technology Data Exchange (ETDEWEB)

    Moore, E N; Robbins, C C; Murdock, D W

    1988-01-01

    A new plutonium triflouride preciptation facility was successfully started up on the first attempt May 13, 1987 at the Savannah River Plant (SRP). This new facility provided a 75% reduction in radiation exposure, a substantial improvement in process performance, and elimination of the major SRP process bottleneck. This was accomplished through sound engineering, improved process control, process automation, and extensive testing of components, assemblies, and entire system prior to ''hot'' startup.

  5. Pollution control in oil, gas and chemical plants

    CERN Document Server

    Bahadori, Alireza

    2014-01-01

    This unique book covers the fundamental requirements for air, soil, noise and water pollution control in oil and gas refineries, chemical plants, oil terminals, petrochemical plants, and related facilities. Coverage includes design and operational considerations relevant to critical systems such as monitoring of water pollution control, equipment, and engineering techniques as well as engineering/technological methods related to soil, noise and air pollution control. This book also: ·         Covers a diverse list of pollution control strategies important to practitioners, ranging from waste water gathering systems and oil/suspended solids removal to chemical flocculation units, biological treatment, and sludge handling and treatment ·         Provides numerous step-by-step tutorials that orient both entry level and veteran engineers to the essentials of pollution control methods in petroleum and chemical industries ·         Includes a comprehensive glossary providing readers with...

  6. The role of plant disease in the development of controlled ecological life support systems

    Science.gov (United States)

    Nelson, B.

    1986-01-01

    Plant diseases could be important factors affecting growth of higher plants in Closed Ecological Life Support Systems (CELSS). Disease control, therefore, will be needed to maintain healthy plants. The most important controls should be aimed at preventing the introduction, reproduction and spread of pathogens and preventing plant infection. An integrared ease control program will maximize that approach. In the design and operation of CELSS, plant disease should be considered an important aspect of plant growth. The effects of plant diseases are reviewed and several disease control measures are discussed.

  7. ITER fast plant system controller prototype based on ATCA platform

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, B., E-mail: bruno@ipfn.ist.utl.pt [Instituto de Plasmas e Fusao Nuclear - Laboratorio Associado, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, P-1049-001 Lisboa (Portugal); Sousa, J.; Carvalho, B.B.; Batista, A.; Neto, A.; Santos, B.; Duarte, A.; Valcarcel, D.; Alves, D.; Correia, M.; Rodrigues, A.P.; Carvalho, P.F. [Instituto de Plasmas e Fusao Nuclear - Laboratorio Associado, Instituto Superior Tecnico, Universidade Tecnica de Lisboa, P-1049-001 Lisboa (Portugal); Ruiz, M. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Universidad Politecnica de Madrid (Spain); Vega, J.; Castro, R. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, CIEMAT, Av. Complutense, Madrid (Spain); Lopez, J.M. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, Universidad Politecnica de Madrid (Spain); Utzel, N.; Makijarvi, P. [ITER Organization, CS 90 046, 13067 St. Paul lez Durance Cedex (France)

    2012-12-15

    The ITER fast plan system controllers (FPSC) are based on embedded technologies. The FPSCs [1] will be devoted to data acquisition tasks (sampling rates >1 kSPS) and control purposes in closed-control loops whose cycle times are below 1 ms. Fast controllers will be dedicated industrial controllers with the ability to supervise other fast and/or slow controllers and interface to actuators, sensors and high performance networks. This contribution presents an FPSC prototype, specialized for data acquisition, based on the ATCA (Advanced Telecommunications Computing Architecture) standard. This prototyping activity contributes to the ITER Plant Control Design Handbook (PCDH) effort of standardization, specifically regarding fast controller characteristics. For the prototype, IPFN has developed a new family of ATCA modules targeting ITER requirements. This family of modules comprises an AMC (Advanced Mezzanine Card) carrier/data hub/timing hub, compliant with the upcoming ATCA extensions for Physics, and a multi-channel galvanically isolated PnP digitizer, designed for serviceability. The design and test of a peer-to-peer communications layer for the implementation of a reflective memory over PCI Express and the design and test of an IEEE-1588 transport layer over an high performance serial link were also performed. In this contribution, a complete description of the solution is presented as well as the integration of the controller into the standard CODAC environment. The most relevant test results will be addressed, focusing in the benefits and limitations of the applied technologies.

  8. Epigenetic Control of Defense Signaling and Priming in Plants

    Science.gov (United States)

    Espinas, Nino A.; Saze, Hidetoshi; Saijo, Yusuke

    2016-01-01

    Immune recognition of pathogen-associated molecular patterns or effectors leads to defense activation at the pathogen challenged sites. This is followed by systemic defense activation at distant non-challenged sites, termed systemic acquired resistance (SAR). These inducible defenses are accompanied by extensive transcriptional reprogramming of defense-related genes. SAR is associated with priming, in which a subset of these genes is kept at a poised state to facilitate subsequent transcriptional regulation. Transgenerational inheritance of defense-related priming in plants indicates the stability of such primed states. Recent studies have revealed the importance and dynamic engagement of epigenetic mechanisms, such as DNA methylation and histone modifications that are closely linked to chromatin reconfiguration, in plant adaptation to different biotic stresses. Herein we review current knowledge regarding the biological significance and underlying mechanisms of epigenetic control for immune responses in plants. We also argue for the importance of host transposable elements as critical regulators of interactions in the evolutionary “arms race” between plants and pathogens. PMID:27563304

  9. Epigenetic control of defense signaling and priming in plants

    Directory of Open Access Journals (Sweden)

    Nino Asuela Espinas

    2016-08-01

    Full Text Available Immune recognition of pathogen-associated molecular patterns or effectors leads to defense activation at the pathogen challenged sites. This is followed by systemic defense activation at distant non-challenged sites, termed systemic acquired resistance (SAR. These inducible defenses are accompanied by extensive transcriptional reprogramming of defense-related genes. SAR is associated with priming, in which a subset of these genes is kept at a poised state to facilitate subsequent transcriptional regulation. Transgenerational inheritance of defense-related priming in plants indicates the stability of such primed states. Recent studies have revealed the importance and dynamic engagement of epigenetic mechanisms, such as DNA methylation and histone modifications that are closely linked to chromatin reconfiguration, in plant adaptation to different biotic stresses. Herein we review current knowledge regarding the biological significance and underlying mechanisms of epigenetic control for immune responses in plants. We also argue for the importance of host transposable elements (TEs as critical regulators of interactions in the evolutionary arms race between plants and pathogens.

  10. Soil microorganisms control plant ectoparasitic nematodes in natural coastal foredunes.

    Science.gov (United States)

    Piśkiewicz, Anna M; Duyts, Henk; Berg, Matty P; Costa, Sofia R; van der Putten, Wim H

    2007-06-01

    Belowground herbivores can exert important controls on the composition of natural plant communities. Until now, relatively few studies have investigated which factors may control the abundance of belowground herbivores. In Dutch coastal foredunes, the root-feeding nematode Tylenchorhynchus ventralis is capable of reducing the performance of the dominant grass Ammophila arenaria (Marram grass). However, field surveys show that populations of this nematode usually are controlled to nondamaging densities, but the control mechanism is unknown. In the present study, we first established that T. ventralis populations are top-down controlled by soil biota. Then, selective removal of soil fauna suggested that soil microorganisms play an important role in controlling T. ventralis. This result was confirmed by an experiment where selective inoculation of microarthropods, nematodes and microbes together with T. ventralis into sterilized dune soil resulted in nematode control when microbes were present. Adding nematodes had some effect, whereas microarthropods did not have a significant effect on T. ventralis. Our results have important implications for the appreciation of herbivore controls in natural soils. Soil food web models assume that herbivorous nematodes are controlled by predaceous invertebrates, whereas many biological control studies focus on managing nematode abundance by soil microorganisms. We propose that soil microorganisms play a more important role than do carnivorous soil invertebrates in the top-down control of herbivorous ectoparasitic nematodes in natural ecosystems. This is opposite to many studies on factors controlling root-feeding insects, which are supposed to be controlled by carnivorous invertebrates, parasitoids, or entomopathogenic nematodes. Our conclusion is that the ectoparasitic nematode T. ventralis is potentially able to limit productivity of the dune grass A. arenaria but that soil organisms, mostly microorganisms, usually prevent the

  11. MicroFit: um software gratuito para desenvolvimento e ajuste de modelos matemáticos de crescimento bacteriano

    Directory of Open Access Journals (Sweden)

    Alisson Amorim Siqueira

    2014-12-01

    Full Text Available A conservação de alimentos é uma das práticas mais antigas apropriadas pela humanidade, entretanto as infecções alimentares ainda despontam como uma gravíssima questão de saúde pública em todo o mundo, levando a óbito milhares de pessoas todos os anos. Nesse contexto, os modelos de predição microbiológica surgem como uma importante ferramenta para aferição da segurança alimentar e avaliação do risco de contaminação de alimentos. Os parâmetros de predição do comportamento microbiano proporcionam um caminho rápido e relativamente econômico para obtenção de estimativas confiáveis sobre crescimento, inativação e sobrevivência durante a atividade de micro-organismos nos alimentos, de acordo com as condições de estocagem. Apesar da importância dos modelos de predição, as dificuldades de utilização e resolução dos mesmos, por consistirem de equações não lineares e sem solução analítica, impedem sua ampla utilização. A baixa disponibilidade de programas eletrônicos para análise de dados microbiológicos, bem como a falta de ferramentas que permitam a criação de modelos ou o ajuste de parâmetros de uma forma rápida e fácil são outros entraves ao uso dos modelos de crescimento microbiológico. Diante desse problema, esse artigo tem por objetivo descrever o processo de desenvolvimento de um software concebido para permitir o ajuste, criação e comparação de modelos microbiológicos de crescimento de bactérias. A partir do uso de ferramentas comumente empregadas nesse tipo de estudo e das necessidades não contempladas por elas, foi desenvolvido um programa autônomo, gratuito, dotado de uma interface objetiva e com mecanismos capazes de criar e avaliar facilmente modelos preditivos. Espera-se que o software desenvolvido neste trabalho possa facilitar a análise de dados do comportamento microbiano em alimentos e o controle de possíveis repercussões para o consumidor final.

  12. Modeling and control for closed environment plant production systems

    Science.gov (United States)

    Fleisher, David H.; Ting, K. C.; Janes, H. W. (Principal Investigator)

    2002-01-01

    A computer program was developed to study multiple crop production and control in controlled environment plant production systems. The program simulates crop growth and development under nominal and off-nominal environments. Time-series crop models for wheat (Triticum aestivum), soybean (Glycine max), and white potato (Solanum tuberosum) are integrated with a model-based predictive controller. The controller evaluates and compensates for effects of environmental disturbances on crop production scheduling. The crop models consist of a set of nonlinear polynomial equations, six for each crop, developed using multivariate polynomial regression (MPR). Simulated data from DSSAT crop models, previously modified for crop production in controlled environments with hydroponics under elevated atmospheric carbon dioxide concentration, were used for the MPR fitting. The model-based predictive controller adjusts light intensity, air temperature, and carbon dioxide concentration set points in response to environmental perturbations. Control signals are determined from minimization of a cost function, which is based on the weighted control effort and squared-error between the system response and desired reference signal.

  13. Ajuste del Índice de Pont para mujeres y hombres

    Directory of Open Access Journals (Sweden)

    Paula María Nava–Salcedo

    2014-07-01

    Full Text Available La forma de arco dental de mujeres y hombres es diferente, en los hombres es amplio y en mujeres de forma parabólica. En ortodoncia existen índices y métodos para la predicción del ancho y forma del arco ideal, uno de estos índices es el de Pont que no toma en cuenta las diferencias entre sexos. Objetivos: determinar la efectividad del índice de Pont al emplearlo en hombres y mujeres, realizar el ajuste si fuera necesario a las formulas del índice de Pont para poder aplicarlo en hombres y mujeres. Materiales y métodos: investigación descriptiva, no experimental y transversal. La muestra fue de 139 modelos de estudio, 94 de pacientes femeninos y 45 de pacientes masculinos, por lo que se seleccionaron 45 modelos de pacientes femeninos de forma aleatoria para igualar las muestras. Se compararon mediante una t de Student los valores reales de la muestra de hombres con los de las mujeres y el resultado del análisis de Pont en hombres y mujeres. Se realizó el ajuste de las constantes del índice de Pont para mujeres y  hombres, se aplicó a ambas poblaciones, el resultado se  comparó con los valores reales interpremolar e intermolar en maxilar y mandíbula. Resultados: el análisis de Pont no es efectivo para utilizarse en mujeres y hombres de Nayarit, se encontraron diferencias transversales entre ambas poblaciones, los ajustes realizados para la población femenina y masculinafue efectiva para utilizase en la población de Nayarit. Conclusiones: El índice de Pont no es aplicable debido a que sobreestima los valores de la población femenina y masculinade la población de Nayarit. Los ajustes realizados fueron efectivos y se recomienda evaluarlo en otras poblaciones.

  14. Ajuste del Índice de Pont para mujeres y hombres

    OpenAIRE

    Paula María Nava–Salcedo; Jaime Fabián Gutiérrez–Rojo; Alma Rosa Rojas–García

    2014-01-01

    La forma de arco dental de mujeres y hombres es diferente, en los hombres es amplio y en mujeres de forma parabólica. En ortodoncia existen índices y métodos para la predicción del ancho y forma del arco ideal, uno de estos índices es el de Pont que no toma en cuenta las diferencias entre sexos. Objetivos: determinar la efectividad del índice de Pont al emplearlo en hombres y mujeres, realizar el ajuste si fuera necesario a las formulas del índice de Pont para poder aplicarlo en hombres y muj...

  15. Proceso de ajuste emocional de padres cuyos hijos presentan algún tipo de discapacidad

    OpenAIRE

    Alcíbar Sánchez, B; Amador Velázquez, R.

    2014-01-01

    La discapacidad se vive desde diferentes perspectivas ya sea padre, hijo, hermano, etc., y cada uno trata de sobreponerse a esta situación dependiendo de los recursos con los que cuente cada persona ya que tiene un impacto social, familiar y psicológico. En cuanto a lo psicológico, se enfrentan un sin fin de emociones contradictorias necesitando ayuda de profesionales para un adecuado manejo de la situación. El estudio tuvo como objetivo la aplicación de la Escala de ajustes para padres con h...

  16. Familias con un hijo con cáncer: ajuste, crianza parental y calidad de vida

    OpenAIRE

    Torrado Val, Elena

    2015-01-01

    El diagnóstico de Cáncer en un hijo es un evento traumático que afecta a toda la familia. El objetivo de este trabajo fue evaluar, describir y comparar la Calidad de Vida relacionada con la Salud Infantil, el Ajuste y Crianza Parental y explorar la relación que existe entre estas variables en familias con un hijo diagnosticado de Cáncer Infantil en tratamiento. Se evaluaron 80 sujetos pertenecientes a 20 familias; distribuidos en 4 grupos de estudio: madres (N=20), padres (N=20), hijos enf...

  17. Disposiciones tributarias sobre ajustes por inflación y sus efectos en las empresas

    Directory of Open Access Journals (Sweden)

    Jaime Bernal Román

    1990-04-01

    Full Text Available RESUMEN  Los Decretos 2686 y 2687 de 1988 que tratan  los ajustes por inflación de los Estados financieros en Colombia, contemplan uno de los temas más novedosos que en materia financiera  se dan en los últimos tiempos en nuestro medio. En Colombia no hemos estado acostumbrados a deflactar Estados Financieros, nunca hemos ajustado para efectos fiscales, no para efectos comerciales la Contabilidad. El presente artículo señala las principales medidas adoptadas por el Gobierno tratando de corregir el efecto distorsionante de la inflación y su principal incidencia en las Empresas Nacionales.

  18. ITER Fast Plant System Controller prototype based on PXIe platform

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, M., E-mail: mariano.ruiz@upm.es [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, CAEND CSIC-UPM Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 (Spain); Vega, J.; Castro, R. [Asociacion EURATOM/CIEMAT para Fusion, Madrid (Spain); Sanz, D.; Lopez, J.M.; Arcas, G. de; Barrera, E.; Nieto, J. [Grupo de Investigacion en Instrumentacion y Acustica Aplicada, CAEND CSIC-UPM Universidad Politecnica de Madrid, Crta. Valencia Km-7, Madrid 28031 (Spain); Goncalves, B.; Sousa, J.; Carvalho, B. [Associacao EURATOM/IST, Lisbon (Portugal); Utzel, N.; Makijarvi, P. [ITER Organization, CS 90 046, 13067 St. Paul lez Durance Cedex (France)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Implementation of Fast Plant System Controller (FPSC) for ITER CODAC. Black-Right-Pointing-Pointer Efficient data acquisition and data movement using EPICS. Black-Right-Pointing-Pointer Performance of PCIe technologies in the implementation of FPSC. - Abstract: The ITER Fast Plant System Controller (FPSC) is based on embedded technologies. The FPSC will be devoted to both data acquisition tasks (sampling rates higher than 1 kHz) and control purposes (feedback loop actuators). Some of the essential requirements of these systems are: (a) data acquisition and data preprocessing; (b) interfacing with different networks and high speed links (Plant Operation Network, timing network based on IEEE1588, synchronous data transference and streaming/archiving networks); and (c) system setup and operation using EPICS (Experimental Physics and Industrial Control System) process variables. CIEMAT and UPM have implemented a prototype of FPSC using a PXIe (PCI eXtension for Instrumentation) form factor in a R and D project developed in two phases. The paper presents the main features of the two prototypes developed that have been named alpha and beta. The former was implemented using LabVIEW development tools as it was focused on modeling the FPSC software modules, using the graphical features of LabVIEW applications, and measuring the basic performance in the system. The alpha version prototype implements data acquisition with time-stamping, EPICS monitoring using waveform process variables (PVs), and archiving. The beta version prototype is a complete IOC implemented using EPICS with different software functional blocks. These functional blocks are integrated and managed using an ASYN driver solution and provide the basic functionalities required by ITER FPSC such as data acquisition, data archiving, data pre-processing (using both CPU and GPU) and streaming.

  19. Una nota sobre el ajuste del IVA en el sistema foral de financiación: Marco analítico y propuesta de un nuevo mecanismo

    OpenAIRE

    Antoni Zabalza

    2012-01-01

    Esta nota aborda tres cuestiones. En primer lugar, la inferencia del marco económico subyacente bajo el mecanismo de ajuste del IVA en el sistema foral de financiación, que se introdujo en la Ley 49/1985, de 27 de diciembre; en segundo lugar, un análisis de los problemas asociados a este ajuste; y en tercer lugar, la propuesta de un nuevo mecanismo de ajuste que resuelve los problemas del anterior.

  20. Simulation-based biagnostics and control for nuclar power plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.C.

    1993-01-01

    Advanced simulation-based diagnostics and control guidance systems for the identification and management of off-normal transient events in nuclear power plants is currently under investigation. To date a great deal of progress has been made in effectively and efficiently combining information obtained through fuzzy pattern recognition and macroscopic mass and energy inventory analysis for use in multiple failure diagnostics. Work has also begun on the unique problem of diagnostics and surveillance methodologies for advanced passively-safe reactors systems utilizing both statistical and fuzzy information. Plans are also being formulated for the development of deterministic optimal control algorithms combined with Monte Carlo incremental learning algorithms to be used for the flexible and efficient control of reactor transients.

  1. COMMERCIAL UTILITY PERSPECTIVES ON NUCLEAR POWER PLANT CONTROL ROOM MODERNIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey C. Joe; Ronald L. Boring; Julius J. Persensky

    2012-07-01

    Commercial nuclear power plants (NPPs) in the United States need to modernize their main control rooms (MCR). Many NPPs have done partial upgrades with some success and with some challenges. The Department of Energy’s (DOE) Light Water Reactor Sustainability (LWRS) Program, and in particular the Advanced Instrumentation and Controls (I&C) and Information Systems Technologies Research and Development (R&D) Pathway within LWRS, is designed to assist commercial nuclear power industry with their MCR modernization efforts. As part of this framework, a survey was issued to utility representatives of the LWRS Program Advanced Instrumentation, Information, and Control Systems/Technologies (II&C) Utility Working Group to obtain their views on a range of issues related to MCR modernization, including: drivers, barriers, and technology options, and the effects these aspects will have on concepts of operations, modernization strategies, and staffing. This paper summarizes the key survey results and discusses their implications.

  2. Using Plant Phylogenetic Relatedness as a Predictor for Plants' Control on Soil Microbial Communities and Nitrogen Cycling

    Science.gov (United States)

    Potter, T.; Bowman, W. D.

    2016-12-01

    Despite the known importance of soil microbes and their influence on soil processes, a mechanistic understanding is still needed to predict how plants and soil microbes interact at scales that are relevant to community and ecosystem-scale processes. Closely related plant species have similar traits aboveground, but we don't know whether this is also true for belowground traits that affect soil microbial community structure and function. Determining how tightly plant phylogeny and plant functional traits are linked to soil microbial communities is a useful approach for discovering plant-microbe associations that are generalizable across plant species (a limitation of studies that employ a single or few plant species). Using this approach, we conducted a greenhouse study with seven congeneric grasses (genus Poa) and their native soils to examine whether plants' influences on microbial community structure were consistent with plant phylogenetic relatedness and/or plant functional traits. Seeds of each Poa species were planted in native soil (from the seed source population) as well as a homogenized soil from all seven populations. Additionally, a nitrogen treatment was added to address how an environmental change (such as nitrogen deposition) alters plant-microbe associations. Rhizosphere community composition of bacteria and fungi was obtained via marker gene sequencing to compare community composition across plant species. Patterns in plant-microbe associations across plant species reveal plant control on nutrient cycling via plant species' influence on microbial community structure. These results determine if we are ready to generalize about plant-microbe interactions at the genus level, an important stepping-stone to applying knowledge of plant-microbe interactions to larger ecological scales.

  3. Parasitic plants in agriculture: Chemical ecology of germination and host-plant location as targets for sustainable control: A review

    Science.gov (United States)

    Justin B. Runyon; John F. Tooker; Mark C. Mescher; Consuelo M. De Moraes

    2009-01-01

    Parasitic plants are among the most problematic pests of agricultural crops worldwide. Effective means of control are generally lacking, in part because of the close physiological connection between the established parasite and host plant hindering efficient control using traditional methods. Seed germination and host location are critical early-growth stages that...

  4. Plant-centered biosystems in space environments: technological concepts for developing a plant genetic assessment and control system.

    Science.gov (United States)

    Lomax, Terri L; Findlay, Kirk A; White, T J; Winner, William E

    2003-06-01

    Plants will play an essential role in providing life support for any long-term space exploration or habitation. We are evaluating the feasibility of an adaptable system for measuring the response of plants to any unique space condition and optimizing plant performance under those conditions. The proposed system is based on a unique combination of systems including the rapid advances in the field of plant genomics, microarray technology for measuring gene expression, bioinformatics, gene pathways and networks, physiological measurements in controlled environments, and advances in automation and robotics. The resulting flexible module for monitoring and optimizing plant responses will be able to be inserted as a cassette into a variety of platforms and missions for either experimental or life support purposes. The results from future plant functional genomics projects have great potential to be applied to those plant species most likely to be used in space environments. Eventually, it will be possible to use the plant genetic assessment and control system to optimize the performance of any plant in any space environment. In addition to allowing the effective control of environmental parameters for enhanced plant productivity and other life support functions, the proposed module will also allow the selection or engineering of plants to thrive in specific space environments. The proposed project will advance human exploration of space in the near- and mid-term future on the International Space Station and free-flying satellites and in the far-term for longer duration missions and eventual space habitation.

  5. AUTOMATION AND CONTROL OF A CROSS-FLOW MICRO-FILTRATION PLANT: APPLICATION TO TROPICAL FRUITS PROCESSING

    Directory of Open Access Journals (Sweden)

    EDINSON FRANCO MEJIA

    2011-01-01

    Full Text Available Este artículo presenta los resultados de una investigación aplicada a la automatización de una planta de microfiltración tangencial utilizada para el tratamiento de jugos de frutas tropicales. Con base en el estudio de las condiciones de operación de la planta original, mediante el análisis de las variables y de los lazos de control, se describen los instrumentos que se seleccionaron para la automatización y el control de las variables de operación, así como la herramienta computacional que se empleó para la adquisición y el registro de datos. Finalmente, se muestra la metodología de ajuste de los lazos de control de los subsistemas de la planta a partir de curvas de reacción y de técnicas heurísticas.

  6. Active current control in wind power plants during grid faults

    DEFF Research Database (Denmark)

    Martinez, Jorge; Kjær, Phillip C.; Rodriguez, Pedro

    2010-01-01

    , wind turbines usually have solutions that enable the turbines to control the generation of reactive power during faults. This paper addresses the importance of using an optimal injection of active current during faults in order to fulfil these grid codes. This is of relevant importance for severe......Modern wind power plants are required and designed to ride through faults in electrical networks, subject to fault clearing. Wind turbine fault current contribution is required from most countries with a high amount of wind power penetration. In order to comply with such grid code requirements...

  7. 78 FR 64909 - Southwestern Region: Invasive Plant Control Project, Carson and Santa Fe National Forests, New...

    Science.gov (United States)

    2013-10-30

    ... Forest Service Southwestern Region: Invasive Plant Control Project, Carson and Santa Fe National Forests... prepare an environmental impact statement (EIS) for controlling invasive plants in the Carson and Santa Fe... and correct deficiencies identified in the 2005 Invasive Plant Control Project Final Environmental...

  8. 77 FR 28407 - Special Nuclear Material Control and Accounting Systems for Nuclear Power Plants

    Science.gov (United States)

    2012-05-14

    ... COMMISSION Special Nuclear Material Control and Accounting Systems for Nuclear Power Plants AGENCY: Nuclear...-5028, ``Special Nuclear Material Control and Accounting Systems for Nuclear Power Plants.'' In DG-5028... Control and Accounting Systems for Nuclear Power Plants.'' DATES: Submit comments by July 16, 2012...

  9. 50 CFR 35.7 - Control of wildfires, insects, pest plants, and disease.

    Science.gov (United States)

    2010-10-01

    ... MANAGEMENT General Rules § 35.7 Control of wildfires, insects, pest plants, and disease. To the extent necessary, the Director shall prescribe measures to control wildfires, insects, pest plants, and disease to... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Control of wildfires, insects, pest plants...

  10. 33 CFR Appendix B to Part 273 - Information Requirements for Aquatic Plant Control Program Reports

    Science.gov (United States)

    2010-07-01

    ... Aquatic Plant Control Program Reports B Appendix B to Part 273 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. B Appendix B to Part 273—Information Requirements for Aquatic Plant Control Program Reports 1. Location and...

  11. 33 CFR Appendix A to Part 273 - Aquatic Plant Control Program Legislative Authority

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Aquatic Plant Control Program... OF THE ARMY, DEPARTMENT OF DEFENSE AQUATIC PLANT CONTROL Pt. 273, App. A Appendix A to Part 273—Aquatic Plant Control Program Legislative Authority Section 104 of the Rivers and Harbors Act, approved...

  12. Medicinal plants and secondary metabolites for diabetes mellitus control

    Directory of Open Access Journals (Sweden)

    Mahmoud Bahmani

    2014-09-01

    Full Text Available Diabetes mellitus is one of the most common and complex problems of modern societies which has caused many economic and social problems. Because diabetes has no definite treatment, the use of traditional medicine seems to be an appropriate solution to control and manage it. Studies revealed that Vaccinium Arctostaphylos L., Securigera securidaca L., Gymnema sylvestre L., Atriplex halimus L., Camellia sinensis L., Ginkgo biloba L., Mamordica charantia L., Citrullus colocynthis (L. Schrad., Allium cepa L., Allium sativum L., Silybum marianum (L., Gaertn and Trigonella foenum graecum L. are effective against diabetes. Flavonoids, quercin, metformin, quinolizidine, anthocyanin, catechin and flavone, phenylpropanoids, lipoic acid and coumarin metabolites were introduced major impact on diabetes. With regard to the study of plants and their metabolites and the mechanisms of their influence, it is clear that these plants have the potential to reduce blood sugar and diabetes and be considered as candidates for preparing new drugs. Combination of plants extracts or their components may also have synergistic effects to better act on diabetes.

  13. Physiological parameters controlling plant-atmosphere ammonia exchange

    Science.gov (United States)

    Schjoerring, Jan K.; Husted, Søren; Mattsson, Marie

    Recent advances in characterizing the influence of different physiological and environmental parameters on NH 3 exchange between plants and the atmosphere are presented. A central parameter in controlling the rate and direction of NH 3 fluxes is the NH 3 compensation point. It may vary from below 1 to over 20 nmol NH 3 mol -1 air. High compensation points seem to be a result of high tissue N status, rapid absorption of NH +4 from the root medium and/or low activity of glutamine synthetase, a key enzyme in NH +4 assimilation. These conditions cause the NH +4 concentration in leaf apoplast and leaf cells to increase. The NH 3 compensation point also depends on plant developmental stage with peaks in NH 3 emission related to leaf senescence and N remobilization. The leaf temperature has a profound influence on the NH 3 compensation point: an increase in temperature from 15 to 30°C may cause a plant to switch from being a strong sink for atmospheric NH 3 to being a significant NH 3 source. Stomatal conductance for NH 3 relative to that of water vapour increases with tissue N status and with leaf senescence. At a given leaf temperature, the NH 3 compensation point can be successfully predicted on basis of the pH and NH +4 concentration in the apoplast of the mesophyll cells.

  14. Herbivores and nutrients control grassland plant diversity via light limitation.

    Energy Technology Data Exchange (ETDEWEB)

    Borer, Elizabeth T. [Department of Ecology, Evolution, and Behavior, University of Minnesota; et al, et al

    2014-01-01

    Human alterations to nutrient cycles1,2 and herbivore communities3–7 are affecting global biodiversity dramatically2. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems8,9. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  15. Nonlinear Fuzzy Model Predictive Control for a PWR Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Xiangjie Liu

    2014-01-01

    Full Text Available Reliable power and temperature control in pressurized water reactor (PWR nuclear power plant is necessary to guarantee high efficiency and plant safety. Since the nuclear plants are quite nonlinear, the paper presents nonlinear fuzzy model predictive control (MPC, by incorporating the realistic constraints, to realize the plant optimization. T-S fuzzy modeling on nuclear power plant is utilized to approximate the nonlinear plant, based on which the nonlinear MPC controller is devised via parallel distributed compensation (PDC scheme in order to solve the nonlinear constraint optimization problem. Improved performance compared to the traditional PID controller for a TMI-type PWR is obtained in the simulation.

  16. A coordinated MIMO control design for a power plant using improved sliding mode controller.

    Science.gov (United States)

    Ataei, Mohammad; Hooshmand, Rahmat-Allah; Samani, Siavash Golmohammadi

    2014-03-01

    For the participation of the steam power plants in regulating the network frequency, boilers and turbines should be co-ordinately controlled in addition to the base load productions. Lack of coordinated control over boiler-turbine may lead to instability; oscillation in producing power and boiler parameters; reduction in the reliability of the unit; and inflicting thermodynamic tension on devices. This paper proposes a boiler-turbine coordinated multivariable control system based on improved sliding mode controller (ISMC). The system controls two main boiler-turbine parameters i.e., the turbine revolution and superheated steam pressure of the boiler output. For this purpose, a comprehensive model of the system including complete and exact description of the subsystems is extracted. The parameters of this model are determined according to our case study that is the 320MW unit of Islam-Abad power plant in Isfahan/Iran. The ISMC method is simulated on the power plant and its performance is compared with the related real PI (proportional-integral) controllers which have been used in this unit. The simulation results show the capability of the proposed controller system in controlling local network frequency and superheated steam pressure in the presence of load variations and disturbances of boiler.

  17. Ajustes entre pais e filhos adultos coabitantes: limite e transgressão

    Directory of Open Access Journals (Sweden)

    Celia Regina Henriques

    2011-12-01

    Full Text Available O objetivo deste trabalho é investigar a relação entre pais e filhos adultos coabitantes no ambiente doméstico familiar e sublinhar os aspectos transformadores dessa dimensão interativa. Empreendemos uma discussão teórica interdisciplinar, incluindo autores como Singly, Giddens, Berger e Luckman. Pesquisamos esse universo por meio de um estudo de campo, realizando entrevistas semiestruturadas com oito famílias cariocas de classe média. Foram entrevistadas, separadamente e depois em conjunto, quatro díades mãe-filho, três díades mãe-filha e uma díade pai-filha. Entre os temas que emergiram da análise dos dados, destacamos os ajustes cotidianos nas instâncias relacionais. Verificamos que, na dinâmica interativa, diferentes ajustes cotidianos são estabelecidos. Pais e filhos se autorizam a romper ou esticar as regras de convivência, revelando o aspecto poroso da relação e estabelecendo um contexto propício para se jogar com as regras. Evidencia-se um jogo de reconstrução constante em um movimento ilimitado de avanços e recuos na esfera relacional.

  18. Sistema Computacional para Ajuste de Funções Densidade de Probabilidade

    Directory of Open Access Journals (Sweden)

    Daniel Henrique Breda Binoti

    Full Text Available RESUMO Este trabalho teve por objetivo iniciar, implementar e validar um projeto de construção de um sistema computadorizado para ajuste de funções densidade de probabilidade. O FitFD foi desenvolvido utilizando-se a linguagem de programação Java. Como ambiente de desenvolvimento foram utilizadas a IDE (Integrated Development Environment Netbeans 7.1 e a JDK 7.3 (Java Development Kit. Os testes do sistema foram realizados em ambiente Windows. Foram implementadas no sistema as seguintes funções densidade de probabilidade: Weibull (2P, 3P, 2P com dap mínimo como locação, 3P truncada, hiperbólica (2P, 3P, 2P com dap mínimo como locação, 3P truncada, log-logística (2P, 3P, 2P com dap mínimo como locação, logística generalizada, Fatigue life (2P e 3P e Frechet (2P e 3P. O sistema desenvolvido auxilia os usuários na definição e escolha da fdp que melhor atenda suas necessidades, contudo melhorias são necessárias. O projeto iniciado mostrou-se eficiente para ajustes de funções de densidade probabilidade.

  19. POSIBILIDADES DE ÉXITO DE LA ESTRATEGIA DE AJUSTE FISCAL DE COSTA RICA

    Directory of Open Access Journals (Sweden)

    Eduardo Méndez Q.

    2011-09-01

    Full Text Available Con base en las experiencias de ajuste fiscal de un conjunto amplio de países en diversas coyunturas y empleando combinaciones de políticas distintas, se exploran las posibilidades de éxito para Costa Rica a la luz de la información disponible sobre las medidas fiscales anunciadas. La evidencia internacional muestra que: i una política fiscal restrictiva no conduce necesariamente a una recesión si el ajuste es de una magnitud tal que genere expectativas favorables que lleguen a estimular el consumo y la inversión al punto de compensar los efectos “keynesianos” de la contracción fiscal sobre la actividad económica; ii han probado tener más éxito políticas basadas en la contención de los gastos (especialmente transferencias y salarios que las que se concentran en aumentos de impuestos; iii un ritmo bajo de actividad económica previo a la toma de las medidas no parece afectar los resultados y iv una coyuntura económica mundial adversa atenta contra el éxito del programa.

  20. Antifungal activity of plant extracts with potential to control plant pathogens in pineapple

    Institute of Scientific and Technical Information of China (English)

    Maria Diana Cerqueira Sales; Helber Barcellos Costa; Jose Aires Ventura; Debora Dummer Meira

    2016-01-01

    Objective: To evaluate the in vitro antifungal activity of extracts, resins, oils and mother tinctures from plants against the filamentous fungi Fusarium guttiforme (F. guttiforme) and Chalara paradoxa, and to evaluate the control of the pineapple fusariosis in situ using mother tinctures. Methods: The screening of the antifungal potential of 131 extract forms from 63 plant species was performed in vitro by using plate-hole method. To control pineapple fusar-iosis in situ, preventive and post-infection treatments were performed on detached pineapple leaves of cv. P´erola (susceptible). Results: The quantitative study indicated that among the 49 mother tincture samples analyzed, 46% were effective against F. guttiforme and 29% for the Chalara paradoxa. The natural plant extracts, mother tincture of Glycyrrhiza glabra (MTGG1), mother tincture of Myroxylon balsamum (MTBT2), mother tincture of Aloe vera (MTAV3), mother tincture of Allium sativum (MTAS4), resin of Protium heptaphyllum (RESAM5) and crude extracts of Rhizophora mangle (CEMV6), exhibited an antifungal activity against F. guttiforme. In the preventive treatment against pineapple fusariosis, MTAV3, MTAS4 and MTGG1 were statistically similar to the treatment with tebuconazol fungicide. The curative treatments with MTAV3, MTAS4, MTGG1 and MTBT2 presented similar activity to fungicide (P Conclusions: The findings of the present study concluded that mother tinctures can effectively control phytopathogens. The mother tincture extract of Myroxylon balsamum showed antifungal activity and was used here for the first time for inhibition of phyto-pathogenic fungi. This study paves the way for the development of bioactive natural products with phytosanitary applications, with the added benefits of an environmentally safe and economically viable product.

  1. Antifungal activity of plant extracts with potential to control plant pathogens in pineapple

    Institute of Scientific and Technical Information of China (English)

    Maria Diana Cerqueira Sales; Helber Barcellos Costa; Patrícia Machado Bueno Fernandes; José Aires Ventura; Debora Dummer Meira

    2016-01-01

    Objective:To evaluate the in vitro antifungal activity of extracts,resins,oils and mother tinctures from plants against the filamentous fungi Fusarium guttiforme(F.guttiforme)and Chalara paradoxa,and to evaluate the control of the pineapple fusariosis in situ using mother tinctures.Methods:The screening of the antifungal potential of 131 extract forms from 63 plant species was performed in vitro by using plate-hole method.To control pineapple fusariosis in situ,preventive and post-infection treatments were performed on detached pineapple leaves of cv.Perola(susceptible).Results:The quantitative study indicated that among the 49 mother tincture samples analyzed,46% were effective against F.guttiforme and 29% for the Chalara paradoxa.The natural plant extracts,mother tincture of Glycyrrhiza glabra(MTGG1),mother tincture of Myroxylon balsamum(MTBT2),mother tincture of Aloe vera(MTAV3),mother tincture of Allium sativum(MTAS4),resin of Protium heptaphyllum(RESAM5) and crude extracts of Rhizophora mangle(CEMV6),exhibited an antifungal activity against F.guttiforme.In the preventive treatment against pineapple fusariosis,MTAV3,MTAS4 and MTGG1 were statistically similar to the treatment with tebuconazol fungicide.The curative treatments with MTAV3,MTAS4,MTGG1 and MTBT2 presented similar activity to fungicide(P < 0.05).Conclusions:The findings of the present study concluded that mother tinctures can effectively control phytopathogens.The mother tincture extract of Myroxylon balsamum showed antifungal activity and was used here for the first time for inhibition of phytopathogenic fungi.This study paves the way for the development of bioactive natural products with phytosanitary applications,with the added benefits of an environmentally safe and economically viable product.

  2. An Evolutionarily Conserved Plant RKD Factor Controls Germ Cell Differentiation.

    Science.gov (United States)

    Koi, Satoshi; Hisanaga, Tetsuya; Sato, Katsutoshi; Shimamura, Masaki; Yamato, Katsuyuki T; Ishizaki, Kimitsune; Kohchi, Takayuki; Nakajima, Keiji

    2016-07-11

    In contrast to animals, in which the germ cell lineage is established during embryogenesis, plant germ cells are generated in reproductive organs via reprogramming of somatic cells. The factors that control germ cell differentiation and reprogramming in plants are poorly understood. Members of the RKD subfamily of plant-specific RWP-RK transcription factors have been implicated in egg cell formation in Arabidopsis based on their expression patterns and ability to cause an egg-like transcriptome upon ectopic expression [1]; however, genetic evidence of their involvement is lacking, due to possible genetic redundancy, haploid lethality, and the technical difficulty of analyzing egg cell differentiation in angiosperms. Here we analyzed the factors that govern germ cell formation in the liverwort Marchantia polymorpha. This recently revived model bryophyte has several characteristics that make it ideal for studies of germ cell formation, such as low levels of genetic redundancy, readily accessible germ cells, and the ability to propagate asexually via gemma formation [2, 3]. Our analyses revealed that MpRKD, a single RWP-RK factor closely related to angiosperm RKDs, is preferentially expressed in developing eggs and sperm precursors in M. polymorpha. Targeted disruption of MpRKD had no effect on the gross morphology of the vegetative and reproductive organs but led to striking defects in egg and sperm cell differentiation, demonstrating that MpRKD is an essential regulator of germ cell differentiation. Together with previous findings [1, 4-6], our results suggest that RKD factors are evolutionarily conserved regulators of germ cell differentiation in land plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Smart — STATCOM control strategy implementation in wind power plants

    DEFF Research Database (Denmark)

    Sintamarean, Nicolae Christian; Cantarellas, Antoni Mir; Miranda, H.;

    2012-01-01

    converters is increasing. This paper deals with an advanced control strategy design of a three-level converter performing STATCOM and Active Filter functionalities. The proposed system is called Smart-STATCOM since it has the capability of self-controlling reactive power and harmonic voltages at the same......High penetration of wind energy into the grid may introduce stability and power quality problems due to the fluctuating nature of the wind and the increasing complexity of the power system. By implementing advanced functionalities in power converters, it is possible to improve the performance...... of the wind farm and also to provide grid support, as it is required by the grid codes. One of the main compliance difficulties that can be found in such power plants are related to reactive power compensation and to keep the harmonics content between the allowed limits, even if the power of the WPP...

  4. Antifungal Effect of Plant Essential Oils on Controlling Phytophthora Species

    Science.gov (United States)

    Amini, Jahanshir; Farhang, Vahid; Javadi, Taimoor; Nazemi, Javad

    2016-01-01

    In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vitro condition, the median effective concen- tration (EC50) values (ppm) of plant essential oils and fungicides were measured. In greenhouse, soil infested with Phytophthora species was treated by adding 50 ml of essential oils and fungicides (100 ppm). Disease severity was determined after 28 days. Among two tested plant essential oils, C. citratus had the lowest EC50 values for inhibition of the mycelial growth of P. capsici (31.473), P. melonis (33.097) and P. drechsleri (69.112), respectively. The mean EC50 values for Metalaxyl-Mancozeb on these pathogens were 20.87, 20.06 and 17.70, respectively. Chemical analysis of plant essential oils by GC-MS showed that, among 42 compounds identified from C. citratus, two compounds β-geranial (α-citral) (39.16%) and z-citral (30.95%) were the most abundant. Under the greenhouse condition, Metalaxyl-Mancozeb caused the greatest reduction in disease severity, 84.2%, 86.8% and 92.1% on melon, cucumber, and pepper, respectively. The C. citratus essential oil reduced disease severity from 47.4% to 60.5% compared to the untreated control (p≤0.05). Essential oils of O. basilicum had the lowest effects on the pathogens under in vitro and greenhouse conditions. These results show that essential oils may contribute to the development of new antifungal agents to protect the crops from Phytophthora diseases. PMID:26889111

  5. Antifungal Effect of Plant Essential Oils on Controlling Phytophthora Species

    Directory of Open Access Journals (Sweden)

    Jahanshir Amini

    2016-02-01

    Full Text Available In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vitro condition, the median effective concen- tration (EC₅₀ values (ppm of plant essential oils and fungicides were measured. In greenhouse, soil infested with Phytophthora species was treated by adding 50 ml of essential oils and fungicides (100 ppm. Disease severity was determined after 28 days. Among two tested plant essential oils, C. citratus had the lowest EC₅₀ values for inhibition of the mycelial growth of P. capsici (31.473, P. melonis (33.097 and P. drechsleri (69.112, respectively. The mean EC₅₀ values for Metalaxyl-Mancozeb on these pathogens were 20.87, 20.06 and 17.70, respectively. Chemical analysis of plant essential oils by GC-MS showed that, among 42 compounds identified from C. citratus, two compounds β-geranial (α-citral (39.16% and z-citral (30.95% were the most abundant. Under the greenhouse condition, Metalaxyl-Mancozeb caused the greatest reduction in disease severity, 84.2%, 86.8% and 92.1% on melon, cucumber, and pepper, respectively. The C. citratus essential oil reduced disease severity from 47.4% to 60.5% compared to the untreated control (p≤0.05. Essential oils of O. basilicum had the lowest effects on the pathogens under in vitro and greenhouse conditions. These results show that essential oils may contribute to the development of new antifungal agents to protect the crops from Phytophthora diseases.

  6. PREVENTION AND CONTROL OF DIMETHYLAMINE VAPORS EMISSION: HERBICIDE PRODUCTION PLANT

    Directory of Open Access Journals (Sweden)

    Zorana Arsenijević

    2008-11-01

    Full Text Available The widely used herbicide, dimethylamine salt of 2,4-dichlorophenoxy acetic acid (2,4-D-DMA, is usually prepared by mixing a dimethylamine (DMA aqueous solution with a solid 2,4-dichlorophenoxy acetic acid (2,4-D. The vapors of the both, reactants and products, are potentially hazardous for the environment. The contribution of DMA vapors in overall pollution from this process is most significant, concerning vapor pressures data of these pollutants. Therefore, the control of the air pollution in the manufacture and handling of methylamines is very important. Within this paper, the optimal air pollution control system in preparation of 2,4-D-DMA was developed for the pesticides manufacturing industry. This study employed the simple pollution prevention concept to reduce the emission of DMA vapors at the source. The investigations were performed on the pilot plant scale. To reduce the emission of DMA vapors, the effluent gases from the herbicide preparation zone were passed through the packed bed scrubber (water - scrubbing medium, and the catalytic reactor in sequence. The end result is a substantially improved air quality in the working area, as well as in the urbanized areas located near the chemical plant.

  7. Hormone-controlled UV-B responses in plants.

    Science.gov (United States)

    Vanhaelewyn, Lucas; Prinsen, Els; Van Der Straeten, Dominique; Vandenbussche, Filip

    2016-08-01

    Ultraviolet B (UV-B) light is a portion of solar radiation that has significant effects on the development and metabolism of plants. Effects of UV-B on plants can be classified into photomorphogenic effects and stress effects. These effects largely rely on the control of, and interactions with, hormonal pathways. The fairly recent discovery of the UV-B-specific photoreceptor UV RESISTANCE LOCUS 8 (UVR8) allowed evaluation of the role of downstream hormones, leading to the identification of connections with auxin and gibberellin. Moreover, a substantial overlap between UVR8 and phytochrome responses has been shown, suggesting that part of the responses caused by UVR8 are under PHYTOCHROME INTERACTING FACTOR control. UV-B effects can also be independent of UVR8, and affect different hormonal pathways. UV-B affects hormonal pathways in various ways: photochemically, affecting biosynthesis, transport, and/or signaling. This review concludes that the effects of UV-B on hormonal regulation can be roughly divided in two: inhibition of growth-promoting hormones; and the enhancement of environmental stress-induced defense hormones.

  8. Ajuste personal en niños y adolescentes diabéticos y no diabéticos

    OpenAIRE

    Quesada-Conde, A.B.; Villena, M.D.; Romero, M; Benavides, A

    2016-01-01

    La siguiente investigación pretende comprobar la existencia de posibles diferencias entre un grupo de niños y adolescentes diabéticos con otro que no lo es, en lo que a ajuste personal se refiere. En el estudio participaron un total de 88 familias con hijos de entre 10 y 18 años, de los cuales 42 niños padecían diabetes y los otros 46 no. El instrumento seleccionado para medir el ajuste social (compuesto por las dimensiones de autoestima, confianza en sí mismo, relaciones interpersonales y re...

  9. ESTRATEGIAS DE AJUSTE ANTE CHOQUES HIPOTÉTICOS DE OFERTA Y DEMANDA. Resultados de una encuesta a empresas mexicanas

    OpenAIRE

    Paula Sánchez-Romeu; Ernesto Rattia Lima

    2015-01-01

    En este artículo se analizan estrategias de ajuste para hacer frente a choques hipotéticos de oferta y demanda utilizadas por 1 138 empresas mexicanas encuestadas por el Banco de México en 2012. Los resultados del análisis muestran que la respuesta de las empresas ante los dos tipos de choque en general no es simétrica y que éstas reaccionan combinando estrategias (principalmente eligen reducir costos), con lo cual moderan los ajustes a precios y producción. Más competencia hace que las e...

  10. Information Foraging in Nuclear Power Plant Control Rooms

    Energy Technology Data Exchange (ETDEWEB)

    R.L. Boring

    2011-09-01

    nformation foraging theory articulates the role of the human as an 'informavore' that seeks information and follows optimal foraging strategies (i.e., the 'information scent') to find meaningful information. This paper briefly reviews the findings from information foraging theory outside the nuclear domain and then discusses the types of information foraging strategies operators employ for normal and off-normal operations in the control room. For example, operators may employ a predatory 'wolf' strategy of hunting for information in the face of a plant upset. However, during routine operations, the operators may employ a trapping 'spider' strategy of waiting for relevant indicators to appear. This delineation corresponds to information pull and push strategies, respectively. No studies have been conducted to determine explicitly the characteristics of a control room interface that is optimized for both push and pull information foraging strategies, nor has there been empirical work to validate operator performance when transitioning between push and pull strategies. This paper explores examples of control room operators as wolves vs. spiders and con- cludes by proposing a set of research questions to investigate information foraging in control room settings.

  11. 78 FR 38739 - Special Nuclear Material Control and Accounting Systems for Nuclear Power Plants

    Science.gov (United States)

    2013-06-27

    ... COMMISSION Special Nuclear Material Control and Accounting Systems for Nuclear Power Plants AGENCY: Nuclear... Accounting Systems for Nuclear Power Plants.'' This regulatory guide provides guidance on recordkeeping and... nuclear material control and accounting system requirements for nuclear power plants. This guide applies...

  12. INSETICIDAL OILS FROM AMAZON PLANTS IN CONTROL OF FALL ARMYWORM

    Directory of Open Access Journals (Sweden)

    ANA CLÁUDIA VIEIRA DOS SANTOS

    2016-01-01

    Full Text Available The potential insecticidal of oils from southwestern Amazon plants against Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae was investigated. Initial bioassays were performed with undiluted oils from 11 plant species. The efficacy of the oils was evaluated against eggs and third-instar caterpillars of S. frugiperda. The oils of Copaifera sp. (Leguminosae, Orbignya phalerata (Arecaceae, and Carapa guianensis (Meliaceae displayed a high efficacy against the caterpillars and were used in subsequent concentration-response bioassays, at concentrations established through preliminary tests. The highest nonlethal concentrations of oils and the lowest lethal concentrations were calculated. A completely randomized design was adopted in both bioassays. The LC50 of the oils varied from 7.50 to 60.84% (v/v. Copaifera sp. oil had the highest toxicity and was 6.84-fold more toxic than O. phalerata oil and 8.11-fold more toxic than Carapa guianensis oil. In general, oils from Copaifera sp., O. phalerata, and Carapa guianensis were effective in controlling S. frugiperda caterpillars under laboratory conditions, and are good candidates for use in integrated management programs of corn pests.

  13. Waste receiving and processing plant control system; system design description

    Energy Technology Data Exchange (ETDEWEB)

    LANE, M.P.

    1999-02-24

    The Plant Control System (PCS) is a heterogeneous computer system composed of numerous sub-systems. The PCS represents every major computer system that is used to support operation of the Waste Receiving and Processing (WRAP) facility. This document, the System Design Description (PCS SDD), includes several chapters and appendices. Each chapter is devoted to a separate PCS sub-system. Typically, each chapter includes an overview description of the system, a list of associated documents related to operation of that system, and a detailed description of relevant system features. Each appendice provides configuration information for selected PCS sub-systems. The appendices are designed as separate sections to assist in maintaining this document due to frequent changes in system configurations. This document is intended to serve as the primary reference for configuration of PCS computer systems. The use of this document is further described in the WRAP System Configuration Management Plan, WMH-350, Section 4.1.

  14. HFE safety reviews of advanced nuclear power plant control rooms

    Science.gov (United States)

    Ohara, John

    1994-01-01

    Advanced control rooms (ACR's) will utilize human-system interface (HSI) technologies that may have significant implications for plant safety in that they will affect the operator's overall role and means of interacting with the system. The Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) aspects of HSI's to ensure that they are designed to good HFE principles and support performance and reliability in order to protect public health and safety. However, the only available NRC guidance was developed more than ten years ago, and does not adequately address the human performance issues and technology changes associated with ACR's. Accordingly, a new approach to ACR safety reviews was developed based upon the concept of 'convergent validity'. This approach to ACR safety reviews is described.

  15. La inteligencia emocional y el ajuste psicológico: un estudio transcultural

    OpenAIRE

    Fulquez Castro, Sandra Carina

    2011-01-01

    La intel·ligència emocional (IE) és una competència de l'ésser humà. Així mateix, elements psicològics com l'autoestima, l-autoconfiança, les relacions amb els iguals i les relacions amb els pares -en el cas dels adolescents- constitueixen eines que guien la salut mental i l'adaptació social de l'individu. L'estudi que es presenta demostra l'associació existent entre la IE (atenció emocional -AE- claredat emocional -CE- i reparació emocional -RE) i les variables d'ajust psicològic, així com d...

  16. Uso de herramientas numéricas y computacionales en el ajuste de curvas

    OpenAIRE

    Ascheri, María; Pizarro, Rubén

    2006-01-01

    Nuestro objetivo es introducir a los alumnos de Cálculo Numérico en el uso de la técnica de ajuste de curvas por medio de la regresión con mínimos cuadrados en la solución de problemas de ingeniería, de física y de matemática aplicada, utilizando herramientas numéricas y computacionales. La metodología usada para apoyar el proceso de enseñanza-aprendizaje de este temática particular de Cálculo Numérico con computadora es la siguiente: se combina la enseñanza tradicional, las técnicas grupales...

  17. Nutritional and cultural aspects of plant species selection for a controlled ecological life support system

    Science.gov (United States)

    Hoff, J. E.; Howe, J. M.; Mitchell, C. A.

    1982-01-01

    The feasibility of using higher plants in a controlled ecological life support system is discussed. Aspects of this system considered important in the use of higher plants include: limited energy, space, and mass, and problems relating to cultivation and management of plants, food processing, the psychological impact of vegetarian diets, and plant propagation. A total of 115 higher plant species are compared based on 21 selection criteria.

  18. A predictive controller based on transient simulations for controlling a power plant

    Science.gov (United States)

    Svingen, B.

    2016-11-01

    A predictive governor based on an embedded, online transient simulation was commissioned at Tonstad power plant in Norway in December 2014. This governor controls each individual turbine governor by feeding them modified setpoints. Tonstad power plant consists of 4 × 160 MW + 1 × 320 MW high head Francis turbines. With a yearly production of 3888 GWh, it is the largest in Norway. The plant is a typical high head Norwegian plant with very long tunnels and correspondingly active dynamic behaviour. This new governor system continuously simulates the entire plant, and appropriate actions are taken automatically by special algorithms. The simulations are based on the method of characteristics (MOC). The governing system has been in full operational mode since December 19 2014. The testing period also included special acceptance tests to be able to deliver FRR, both on the Nordic grid and on DC cable to Denmark. Although in full operational mode, this system is still a prototype under constant development. It shows a new way of using transient analysis that may become increasingly important in the future with added power from un-regulated sources such as wind, solar and bio.

  19. Plant-wide modelling and control of nitrous oxide emissions from wastewater treatment plants

    DEFF Research Database (Denmark)

    Boiocchi, Riccardo

    % of those CO2 equivalents comes from N2O emissions. It becomes therefore relevant, within the context of reducing the carbon footprint of wastewater treatment (WWT) systems, to develop control strategies aimed at the minimization of the emissions of this gas. Till now, few operation strategies have been...... environments and a multi-criteria evaluation, taking into account not only the N2O emissions but also the effluent quality and the operational costs, is carried out. This is because the reduction of the carbon footprint of WWT plants cannot be achieved at the expense of worse effluent quality and unreasonably......Nitrous oxide (N2O) is a greenhouses gas with a global warming potential three hundred times stronger than carbon dioxide (CO2). The IPCC report released in 2014 shows that the CO2 equivalents emitted from the wastewater systems are increasing in the last decades. It was also estimated that 14...

  20. El papel de la concertación social ante la política de ajuste

    Directory of Open Access Journals (Sweden)

    Juan Raso Delgue

    2015-10-01

    Full Text Available Contenido: Introducción. Ajuste. Modos de producción y concertación. Nuevos actores y nuevas dimensiones del conflictos. Las dimensiones de la nueva concertación. Contenidos de la nueva concertación. Conclusiones

  1. Plant-microbe interactions promoting plant growth and health: perspectives for controlled use of microorganisms in agriculture.

    Science.gov (United States)

    Berg, Gabriele

    2009-08-01

    Plant-associated microorganisms fulfill important functions for plant growth and health. Direct plant growth promotion by microbes is based on improved nutrient acquisition and hormonal stimulation. Diverse mechanisms are involved in the suppression of plant pathogens, which is often indirectly connected with plant growth. Whereas members of the bacterial genera Azospirillum and Rhizobium are well-studied examples for plant growth promotion, Bacillus, Pseudomonas, Serratia, Stenotrophomonas, and Streptomyces and the fungal genera Ampelomyces, Coniothyrium, and Trichoderma are model organisms to demonstrate influence on plant health. Based on these beneficial plant-microbe interactions, it is possible to develop microbial inoculants for use in agricultural biotechnology. Dependent on their mode of action and effects, these products can be used as biofertilizers, plant strengtheners, phytostimulators, and biopesticides. There is a strong growing market for microbial inoculants worldwide with an annual growth rate of approximately 10%. The use of genomic technologies leads to products with more predictable and consistent effects. The future success of the biological control industry will benefit from interdisciplinary research, e.g., on mass production, formulation, interactions, and signaling with the environment, as well as on innovative business management, product marketing, and education. Altogether, the use of microorganisms and the exploitation of beneficial plant-microbe interactions offer promising and environmentally friendly strategies for conventional and organic agriculture worldwide.

  2. Within-plant distribution of Aulacorthum solani (Hemiptera: Aphididae), on various greenhouse plants with implications for control.

    Science.gov (United States)

    Jandricic, S E; Mattson, N S; Wraight, S P; Sanderson, J P

    2014-04-01

    Foxglove aphid, Aulacorthum solani (Kaltenbach) (Hemiptera: Aphididae), has recently undergone a status change from an occasional pest to a serious pest in greenhouses of North America and the United Kingdom. Little nonanecdotal information exists on the ecology of this insect in greenhouse crops. To help improve integrated pest management decisions for A. solani, the within-plant distribution of this pest was explored on a variety of common greenhouse plants in both the vegetative and flowering stage. This aphid generally was found on lower leaves of vegetative plants, but was found higher in the canopy on reproductive plants (on flowers, flower buds, or upper leaves). Aphid numbers were not consistently positively correlated with total leaf surface areas within plant strata across plant species. Thus, the observed differences in preferred feeding sites on vegetative versus flowering plants are possibly a response to differences in nutritional quality of the various host-plant tissues. Despite being anecdotally described as a "stem-feeding aphid," A. solani was rarely found feeding on stems at the population densities established in our tests, with the exception of racemes of scarlet sage (Salvia splendans). Although some previous reports suggested that A. solani prefers to feed on new growth of plants, our results indicate that mature leaves are preferred over growing tips and young leaves. The implications of the within-plant feeding preferences of A. solani populations with respect to both biological and chemical control are discussed.

  3. Control of the actin cytoskeleton in plant cell growth

    NARCIS (Netherlands)

    Hussey, P.J.; Ketelaar, M.J.; Deeks, M.J.

    2006-01-01

    Plant cells grow through increases in volume and cell wall surface area. The mature morphology of a plant cell is a product of the differential rates of expansion between neighboring zones of the cell wall during this process. Filamentous actin arrays are associated with plant cell growth, and the a

  4. Control and optimization of the refrigeration plant in a brewery

    DEFF Research Database (Denmark)

    Petersen, P.M; Qvale, Einar Bjørn

    1989-01-01

    The design and operation of a refrigeration plant in a brewery has been studied. The plant has been evaluated by using mathematical models of the components to simulate responses to real-life load variations. The study shows that the efficiency and economy of the actual refrigeration plant could...

  5. Plant-wide control: eco-efficiency and control loop configuration.

    Science.gov (United States)

    Munir, M T; Yu, W; Young, B R

    2013-01-01

    Since the eco-efficiency of all industrial processes/plants has become increasingly important, engineers need to find a way to integrate the control loop configuration and the measurements of eco-efficiency. A new measure of eco-efficiency, the exergy eco-efficiency factor, for control loop configuration, is proposed in this paper. The exergy eco-efficiency factor is based on the thermodynamic concept of exergy which can be used to analyse a process in terms of its efficiency associated with the control configuration. The combination of control pairing configuration techniques (such as the relative gain array, RGA and Niederlinski index, NI) and the proposed exergy eco-efficiency factor will guide the process designer to reach the optimal control design with low operational cost (i.e., energy consumption). The exergy eco-efficiency factor is implemented in the process simulation case study and the reliability of the proposed method is demonstrated by dynamic simulation results.

  6. Software Configuration Management Plan for the B-Plant Canyon Ventilation Control System

    Energy Technology Data Exchange (ETDEWEB)

    MCDANIEL, K.S.

    1999-08-31

    Project W-059 installed a new B Plant Canyon Ventilation System. Monitoring and control of the system is implemented by the Canyon Ventilation Control System (CVCS). This Software Configuration Management Plan provides instructions for change control of the CVCS.

  7. Pathogen filtration to control plant disease outbreak in greenhouse production

    Science.gov (United States)

    Jeon, Sangho; Krasnow, Charles; Bhalsod, Gemini; Granke, Leah; Harlan, Blair; Hausbeck, Mary; Zhang, Wei

    2016-04-01

    Previous research has been extensively focused on understanding the fate and transport of human microbial pathogens in soil and water environments. However, little is known about the transport of plant pathogens, although these pathogens are often found in irrigation waters and could cause severe crop damage and economical loss. Water mold pathogens including Phytophthora spp. and Pythium spp. are infective to a wide range of vegetable and floriculture crops, and they are primarily harbored in soils and disseminated through water flow. It is challenging to control these pathogens because they often quickly develop resistance to many fungicides. Therefore, this multi-scale study aimed to investigate physical removal of plant pathogens from water by filtration, thus reducing the pathogen exposure risks to crops. In column-scale experiments, we studied controlling factors on the transport and retention of Phytophthora capsici zoospores in saturated columns packed with iron oxide coated-sand and uncoated-sand under varying solution chemistry. Biflagellate zoospores were less retained than encysted zoospores, and lower solution pH and greater iron oxide content increased the retention of encysted zoospores. These results provided insights on environmental dispersal of Phytophthora zoospores in natural soils as well as on developing cost-effective engineered filtration systems for pathogen removal. Using small-scale greenhouse filtration systems, we further investigated the performance of varying filter media (i.e., granular sand, iron oxide coated ceramic porous media, and activated carbon) in mitigating disease outbreaks of Phytophthora and Pythium for greenhouse-grown squash and poinsettia, respectively, in comparison with fungicide treatment. For squash, filtration by iron oxide coated media was more effective in reducing the Phytophthora infection, comparing to sand filtration and fungicide application. For poinsettia, sand filtration performed better in controlling

  8. Evaluation of MerCAP for Power Plant Mercury Control

    Energy Technology Data Exchange (ETDEWEB)

    Carl Richardson

    2008-09-30

    This report is submitted to the U.S. Department of Energy National Energy Technology Laboratory (DOE-NETL) as part of Cooperative Agreement DE-FC26-03NT41993, 'Evaluation of EPRI's MerCAP{trademark} Technology for Power Plant Mercury Control'. This project has investigated the mercury removal performance of EPRI's Mercury Capture by Amalgamation Process (MerCAP{trademark}) technology. Test programs were conducted to evaluate gold-based MerCAP{trademark} at Great River Energy's Stanton Station Unit 10 (Site 1), which fired both North Dakota lignite (NDL) and Power River Basin (PRB) coal during the testing period, and at Georgia Power's Plant Yates Unit 1 (Site 2) [Georgia Power is a subsidiary of The Southern Company] which fires a low sulfur Eastern bituminous coal. Additional tests were carried out at Alabama Power's Plant Miller, which fires Powder River Basin Coal, to evaluate a carbon-based MerCAP{trademark} process for removing mercury from flue gas downstream of an electrostatic precipitator [Alabama Power is a subsidiary of The Southern Company]. A full-scale gold-based sorbent array was installed in the clean-air plenum of a single baghouse compartment at GRE's Stanton Station Unit 10, thereby treating 1/10th of the unit's exhaust gas flow. The substrates that were installed were electroplated gold screens oriented parallel to the flue gas flow. The sorbent array was initially installed in late August of 2004, operating continuously until its removal in July 2006, after nearly 23 months. The initial 4 months of operation were conducted while the host unit was burning North Dakota lignite (NDL). In November 2004, the host unit switched fuel to burn Powder River Basin (PRB) subbituminous coal and continued to burn the PRB fuel for the final 19 months of this program. Tests were conducted at Site 1 to evaluate the impacts of flue gas flow rate, sorbent plate spacing, sorbent pre-cleaning and regeneration, and spray

  9. Automatic Generation Control Using PI Controller with Bacterial Foraging for both Thermal and Hydro Plants

    Directory of Open Access Journals (Sweden)

    Preeti Hooda,

    2014-06-01

    Full Text Available The load-frequency control (LFC is used to restore the balance between load and generation in each control area by means of speed control. In power system, the main goal of load frequency control (LFC or automatic generation control (AGC is to maintain the frequency of each area and tie- line power flow within specified tolerance by adjusting the MW outputs of LFC generators so as to accommodate fluctuating load demands. In this paper, attempt is made to make a scheme for automatic generation control within a restructured environment considering effects of contracts between DISCOs and GENCOs to make power system network in normal state where, GENCO used are hydro plants as well as thermal plants. The bacterial foraging optimization technique is being developed, which is applied to AGC in an interconnected four area system.The performance of the system is obtained by MATLAB Simulink tool. The results are shown in frequency and power response for four area AGC system. In this paper we have shown practical work by using thermal and hydro both system at Genco’s side.As reheated system transfer function is being used.

  10. Empirical Modeling of Plant Gas Fluxes in Controlled Environments

    Science.gov (United States)

    Cornett, Jessie David

    1994-01-01

    As humans extend their reach beyond the earth, bioregenerative life support systems must replace the resupply and physical/chemical systems now used. The Controlled Ecological Life Support System (CELSS) will utilize plants to recycle the carbon dioxide (CO2) and excrement produced by humans and return oxygen (O2), purified water and food. CELSS design requires knowledge of gas flux levels for net photosynthesis (PS(sub n)), dark respiration (R(sub d)) and evapotranspiration (ET). Full season gas flux data regarding these processes for wheat (Triticum aestivum), soybean (Glycine max) and rice (Oryza sativa) from published sources were used to develop empirical models. Univariate models relating crop age (days after planting) and gas flux were fit by simple regression. Models are either high order (5th to 8th) or more complex polynomials whose curves describe crop development characteristics. The models provide good estimates of gas flux maxima, but are of limited utility. To broaden the applicability, data were transformed to dimensionless or correlation formats and, again, fit by regression. Polynomials, similar to those in the initial effort, were selected as the most appropriate models. These models indicate that, within a cultivar, gas flux patterns appear remarkably similar prior to maximum flux, but exhibit considerable variation beyond this point. This suggests that more broadly applicable models of plant gas flux are feasible, but univariate models defining gas flux as a function of crop age are too simplistic. Multivariate models using CO2 and crop age were fit for PS(sub n), and R(sub d) by multiple regression. In each case, the selected model is a subset of a full third order model with all possible interactions. These models are improvements over the univariate models because they incorporate more than the single factor, crop age, as the primary variable governing gas flux. They are still limited, however, by their reliance on the other environmental

  11. Caracterização dos perfis glicêmicos domiciliares como estratégia para os ajustes insulinoterápicos em pacientes com diabetes mellitus do tipo 1 Caracterización de los perfiles glicémicos domiciliares como estrategia para los ajustes insulino-terápicos en pacientes con diabetes mellitus tipo 1 Glycemic profiles in insulin adjustments in patients with type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Sonia Aurora Alves Grossi

    2003-03-01

    Full Text Available O artigo tem como objetivo principal caracterizar os perfis glicêmicos domiciliares de pacientes com diabetes mellitus tipo1, a partir de um esquema de monitorização proposto, e adotá-los como estratégia de ajuste nas doses de insulina. Foram realizados 3259 testes, 781 antes do café, 752 antes do almoço, 765 antes do jantar, 740 antes de deitar e 221 pela madrugada. A média das glicemias nestes períodos ultrapassaram os limites superiores satisfatórios em 6,87%, 3,83%, 11,37%, 30,50% e 19,28% respectivamente. Estes dados forneceram subsídios para ajustes nos esquemas insulinoterápicos. Os níveis HbA1c não mudaram de forma significante com os ajustes realizados porém, foram mantidos em 10%.El objetivo principal de este artículo consiste en caracterizar los perfiles glicémicos domiciliares de los pacientes con diabetes mellitus tipo 1, a partir de un esquema propuesto de monitorización, para aplicarlo como estrategia, en los ajustes de las dosis de insulina. Fueron realizados 3.259 tests, de los cuales 781se hicieron antes del desayuno, 752 se realizaron antes del almuerzo, 765 antes de la merienda, 740 se hicieron antes de dormir y los 221 se hicieron en la madarugada. La media de las glicemias en estos períodos ultrapasaron los límites superiores satisfactorios em 6,8%, 3,83%, 11,37%, 30,50% y 19,28% respectivamente. Estos datos ofrecieron subsidios para poder ajustar los esquemas insulinoterápicos. Los niveles de HbA1c no variaron de forma significativa com los ajustes realizados y se mantuvieron em 10%.The goal of this paper is to characterize the glycemic profiles of patients with type 1 diabetes mellitus like a strategy in insulin adjustments. A total of 3259 tests were realized being 781 before breakfast, 752 before lunch, 765 before dinner and 740 before bed and 221 in the dawn. The average of the blood glucose tests in these periods oversteped the superior limits in 6,87%, 3,83%, 11,37%, 30,50% e 19,28% respectively

  12. RÉGIMEN HÍDRICO Y AJUSTE OSMÓTICO EN VARIEDADES CUBANAS DE TRIGO (Triticum aestivum Y T. durum CULTIVADAS EN CONDICIONES DE SALINIDAD

    Directory of Open Access Journals (Sweden)

    Leandris Argentel

    2013-01-01

    Full Text Available Los potenciales hídrico y osmótico y el ajuste osmótico en 12 variedades cubanas de trigo pertenecientes a las especies Triticum aestivum y Triticum durum cultivadas en condiciones de salinidad fueron evaluados, siguiendo las metodologías para tales fines. Las plantas se establecieron en un invernadero en condiciones de hidroponía a un nivel de salinidad de 8 dS.m -1 , como control se montó un tratamiento con una conductividad eléctrica de 0,36 dS.m -1 . Las evaluaciones se realizaron a los 25 días posteriores a la germinación. Como resultado se obtuvo una significativa disminución de los valores del potencial hídrico en la mayoría de las variedades en todos los órganos medidos y se observó una significativa disminución de sus valores desde las raíces hasta las hojas para asegurar el gradiente hídrico. Las variedades que no disminuyeron significativamente su potencial hídrico mostraron comportamiento similar en los tres órganos evaluados aunque el gradiente de potenciales se mantuvo. El potencial osmótico disminuyó significativamente en todas las variedades y sus valores fueron inferiores a -0,6 MPa. Todas las variedades realizaron el ajuste osmótico, siendo el valor más significativo AO= 0,3 MPa en las variedades INIFAT RM-36, INIFAT RM-32, INIFAT RM-37. Se observó variabilidad en la respuesta al estrés salino entre variedades y especies para las tres variables evaluadas.

  13. Plant species, atmospheric CO2 and soil N interactively or additively control C allocation within plant-soil systems

    Institute of Scientific and Technical Information of China (English)

    FU; Shenglei; Howard; Ferris

    2006-01-01

    Two plant species, Medicago truncatula (legume) and Avena sativa (non-legume), were grown in low- or high-N soils under two CO2 concentrations to test the hypothesis whether C allocation within plant-soil system is interactively or additively controlled by soil N and atmospheric CO2 is dependent upon plant species. The results showed the interaction between plant species and soil N had a significant impact on microbial activity and plant growth. The interaction between CO2 and soil N had a significant impact on soil soluble C and soil microbial biomass C under Madicago but not under Avena. Although both CO2 and soil N affected plant growth significantly, there was no interaction between CO2 and soil N on plant growth. In other words, the effects of CO2 and soil N on plant growth were additive. We considered that the interaction between N2 fixation trait of legume plant and elevated CO2 might have obscured the interaction between soil N and elevated CO2 on the growth of legume plant. In low-N soil, the shoot-to-root ratio of Avena dropped from 2.63±0.20 in the early growth stage to 1.47±0.03 in the late growth stage, indicating that Avena plant allocated more energy to roots to optimize nutrient uptake (i.e. N) when soil N was limiting. In high-N soil, the shoot-to-root ratio of Medicago increased significantly over time (from 2.45±0.30 to 5.43±0.10), suggesting that Medicago plants allocated more energy to shoots to optimize photosynthesis when N was not limiting.The shoot-to-root ratios were not significantly different between two CO2 levels.

  14. Plant species, atmospheric CO2 and soil N interactively or additively control C allocation within plant-soil systems.

    Science.gov (United States)

    F U, Shenglei; Ferris, Howard

    2006-12-01

    Two plant species, Medicago truncatula (legume) and Avena sativa (non-legume), were grown in low- or high-N soils under two CO2 concentrations to test the hypothesis whether C allocation within plant-soil system is interactively or additively controlled by soil N and atmospheric CO2 is dependent upon plant species. The results showed the interaction between plant species and soil N had a significant impact on microbial activity and plant growth. The interaction between CO2 and soil N had a significant impact on soil soluble C and soil microbial biomass C under Madicago but not under Avena. Although both CO2 and soil N affected plant growth significantly, there was no interaction between CO2 and soil N on plant growth. In other words, the effects of CO2 and soil N on plant growth were additive. We considered that the interaction between N2 fixation trait of legume plant and elevated CO2 might have obscured the interaction between soil N and elevated CO2 on the growth of legume plant. In low-N soil, the shoot-to-root ratio of Avena dropped from 2.63 +/- 0.20 in the early growth stage to 1.47 +/- 0.03 in the late growth stage, indicating that Avena plant allocated more energy to roots to optimize nutrient uptake (i.e. N) when soil N was limiting. In high-N soil, the shoot-to-root ratio of Medicago increased significantly over time (from 2.45 +/- 0.30 to 5.43 +/- 0.10), suggesting that Medicago plants allocated more energy to shoots to optimize photosynthesis when N was not limiting. The shoot-to-root ratios were not significantly different between two CO2 levels.

  15. PLC/PC monitoring, control systems a boon for smaller NGL plants. [Programmable Logic Controllers and Personal Computers

    Energy Technology Data Exchange (ETDEWEB)

    Gill, M.R.; Sisk, L.B.; Warren, W.F. (Texaco Inc., Houston, TX (United States)); Simpson, T.W. (Texaco U.S.A., Velma, OK (United States))

    1993-11-01

    Experience of two plants operated by Texaco U.S.A. indicates that installing monitoring and control systems based on programmable-logic controllers and personal computers (PLC/PC) at smaller NGL plants can improve plant economics and processing of customers' gas and increase personnel safety. Such a system gives management a means to track the performance of a plant while making significant steps to enhance employee motivation, morale, and safety. The operator has access to a large amount of information that he or she can use to analyze alarms as well as optimize plant operation in terms of safety, income, and maintenance costs. In fact, because of his advanced awareness of the state of the plant, he generally functions more in an active than a reactive mode. With a significant amount of data available on which to base decisions, the operator can quickly see the results of his actions on the entire plant without leaving his station.

  16. Plant RNA binding proteins for control of RNA virus infection

    OpenAIRE

    Huh, Sung Un; Paek, Kyung-Hee

    2013-01-01

    Plant RNA viruses have effective strategies to infect host plants through either direct or indirect interactions with various host proteins, thus suppressing the host immune system. When plant RNA viruses enter host cells exposed RNAs of viruses are recognized by the host immune system through processes such as siRNA-dependent silencing. Interestingly, some host RNA binding proteins have been involved in the inhibition of RNA virus replication, movement, and translation through RNA-specific b...

  17. Plant Tolerance: A Unique Approach to Control Hemipteran Pests

    Science.gov (United States)

    Koch, Kyle G.; Chapman, Kaitlin; Louis, Joe; Heng-Moss, Tiffany; Sarath, Gautam

    2016-01-01

    Plant tolerance to insect pests has been indicated to be a unique category of resistance, however, very little information is available on the mechanism of tolerance against insect pests. Tolerance is distinctive in terms of the plant’s ability to withstand or recover from herbivore injury through growth and compensatory physiological processes. Because plant tolerance involves plant compensatory characteristics, the plant is able to harbor large numbers of herbivores without interfering with the insect pest’s physiology or behavior. Some studies have observed that tolerant plants can compensate photosynthetically by avoiding feedback inhibition and impaired electron flow through photosystem II that occurs as a result of insect feeding. Similarly, the up-regulation of peroxidases and other oxidative enzymes during insect feeding, in conjunction with elevated levels of phytohormones can play an important role in providing plant tolerance to insect pests. Hemipteran insects comprise some of the most economically important plant pests (e.g., aphids, whiteflies), due to their ability to achieve high population growth and their potential to transmit plant viruses. In this review, results from studies on plant tolerance to hemipterans are summarized, and potential models to understand tolerance are presented. PMID:27679643

  18. Biological effects of native and exotic plant residues on plant growth, microbial biomass and N availability under controlled conditions

    OpenAIRE

    Diallo, Mariama-Dalanda; Duponnois, Robin; Guisse, A.; Sall, Saïdou; Chotte, Jean-Luc; Thioulouse, J.

    2006-01-01

    The leaf litter of six tropical tree species (Acacia holosericea, Acacia tortilis, Azadirachta indica, Casuarina equisetifolia, Cordyla pinnata and Faidherbia albida) frequently used in agroforestry plantations in Sahelian and Soudano-Sahelian areas were tested for their influence on soil nitrogen content, microbial biomass and plant growth under controlled greenhouse conditions. Half of the soil was planted with onion (Allium cepa L.) seedlings and the other half was not. Two herbaceous spec...

  19. Aquatic Plant Control Research Program: The Rhizosphere Microbiology of Rooted Aquatic Plants.

    Science.gov (United States)

    1988-04-01

    organic compounds materials are flooded periods, a and partially accumulated temporary buildup of degraded plant and reduced organic com- animal matter...extensive mycelium , mycorrhizal fungi also contribute to the stabilization of both the plant and the substrate. The fungi further facili- tate this...excretion of organic materials by plant roots mediates the selection and growth of bacteria in the rhizosphere, any changes that aging brings about in

  20. Plant traits mediate consumer and nutrient control on plant community productivity and diversity.

    Science.gov (United States)

    Eskelinen, Anu; Harrison, Susan; Tuomi, Maria

    2012-12-01

    The interactive effects of consumers and nutrients on terrestrial plant communities, and the role of plant functional traits in mediating these responses, are poorly known. We carried out a six-year full-factorial field experiment using mammalian herbivore exclusion and fertilization in two habitat types (fertile and infertile alpine tundra heaths) that differed in plant functional traits related to resource acquisition and palatability. Infertile habitats were dominated by species with traits indicative of a slow-growing strategy: high C:N ratio, low specific leaf area, and high condensed tannins. We found that herbivory counteracted the effect of fertilization on biomass, and that this response differed between the two habitats and was correlated with plant functional traits. Live biomass dominated the treatment responses in infertile habitats, whereas litter accumulation dominated the treatment responses in fertile habitats and was strongly negatively associated with resident community tannin concentration. Species richness declined under herbivore exclusion and fertilization in fertile habitats, where litter accumulation was greatest. Community means of plant C:N ratio predicted treatment effects on diversity: fertilization decreased and herbivory increased dominance in communities originally dominated by plants with high C:N, while fertilization increased and herbivory diminished dominance in communities where low C:N species were abundant. Our results highlight the close interdependence between consumer effects, soil nutrients, and plant functional traits and suggest that plant traits may provide an improved understanding of how consumers and nutrients influence plant community productivity and diversity.

  1. Plant neighbour identity matters to belowground interactions under controlled conditions.

    Directory of Open Access Journals (Sweden)

    Cristina Armas

    Full Text Available BACKGROUND: Root competition is an almost ubiquitous feature of plant communities with profound effects on their structure and composition. Far beyond the traditional view that plants interact mainly through resource depletion (exploitation competition, roots are known to be able to interact with their environment using a large variety of mechanisms that may inhibit or enhance access of other roots to the resource or affect plant growth (contest interactions. However, an extensive analysis on how these contest root interactions may affect species interaction abilities is almost lacking. METHODOLOGY/PRINCIPAL FINDINGS: In a common garden experiment with ten perennial plant species we forced pairs of plants of the same or different species to overlap their roots and analyzed how belowground contest interactions affected plant performance, biomass allocation patterns, and competitive abilities under abundant resource supply. Our results showed that net interaction outcome ranged from negative to positive, affecting total plant mass and allocation patterns. A species could be a strong competitor against one species, weaker against another one, and even facilitator to a third species. This leads to sets of species where competitive hierarchies may be clear but also to groups where such rankings are not, suggesting that intransitive root interactions may be crucial for species coexistence. CONCLUSIONS/SIGNIFICANCE: The outcome of belowground contest interactions is strongly dependent on neighbours' identity. In natural plant communities this conditional outcome may hypothetically help species to interact in non-hierarchical and intransitive networks, which in turn might promote coexistence.

  2. UNDERSTANDING PLANT-SOIL RELATIONSHIPS USING CONTROLLED ENVIRONMENT FACILITIES

    Science.gov (United States)

    Although soil is a component of terrestrial ecosystems, it is comprised of a complex web of interacting organisms, and therefore, can be considered itself as an ecosystem. Soil microflora and fauna derive energy from plants and plant residues and serve important functions in mai...

  3. Topographic, edaphic, and vegetative controls on plant-available water

    Science.gov (United States)

    Dymond, Salli F.; Bradford, John B.; Bolstad, Paul V.; Kolka, Randall K.; Sebestyen, Stephen D.; DeSutter, Thomas S.

    2017-01-01

    Soil moisture varies within landscapes in response to vegetative, physiographic, and climatic drivers, which makes quantifying soil moisture over time and space difficult. Nevertheless, understanding soil moisture dynamics for different ecosystems is critical, as the amount of water in a soil determines a myriad ecosystem services and processes such as net primary productivity, runoff, microbial decomposition, and soil fertility. We investigated the patterns and variability in in situ soil moisture measurements converted to plant-available water across time and space under different vegetative cover types and topographic positions at the Marcell Experimental Forest (Minnesota, USA). From 0 – 228.6 cm soil depth, plant-available water was significantly higher under the hardwoods (12%), followed by the aspen (8%) and red pine (5%) cover types. Across the same soil depth, toeslopes were wetter (mean plant-available water = 10%) than ridges and backslopes (mean plant-available water was 8%), although these differences were not statistically significant (p plant-available water and that topography was not significantly related to plant-available water within this low-relief landscape. Additionally, during the three-year monitoring period, red pine and quaking aspen sites experienced plant-available water levels that may be considered limiting to plant growth and function. Given that increasing temperatures and more erratic precipitation patterns associated with climate change may result in decreased soil moisture in this region, these species may be sensitive and vulnerable to future shifts in climate.

  4. Genes controlling the development and function of plant vacuoles

    NARCIS (Netherlands)

    Li, Y.

    2017-01-01

    All plant cells contain numerous organelles, like mitochondria chloroplasts, with specific functions that are generally very similar among cell types and species. However, vacuoles, which are by far the largest compartments in plant cells, show a broad diversification in shape, dimensions, content

  5. Comparación entre varias poblaciones estándar para el ajuste por edades

    Directory of Open Access Journals (Sweden)

    Llorca Díaz Javier

    2000-01-01

    Full Text Available FUNDAMENTO: Analizar el efecto que tiene la elección de una población de referencia sobre diferentes indicadores derivados de las tasas de mortalidad ajustadas por edad. MÉTODOS: Las tasas de mortalidad por diferentes causas de muerte en España de 1971 a 1992 son ajustadas empleando cuatro poblaciones de referencia: poblaciones españolas de 1971 y 1992, población estándar europea y población estándar mundial. Los resultados obtenidos con las cuatro poblaciones se comparan empleando tres indicadores: diferencia entre las tasas de 1992 y 1971, razón entre las tasas de 1992 y 1971y cambio anual porcentual entre 1971 y 1992. RESULTADOS: En la mayor parte de las causas de muerte estudiadas incluyendo el total de causas, la cardiopatía isquémica y casi todos los tumores, la razón de tasas y el porcentaje de cambio anual son similares con independencia de cuál sea la población estándar empleada. En cambio, la diferencia de tasas es muy diferente en función de la población de referencia. En las enfermedades infecciosas y el cáncer de testículo se produce la situación contraria: la diferencia de tasas es robusta mientras que la razón de tasas varía con la población estándar. Finalmente, la mortalidad por neumonía, enfermedad de Parkinson y cáncer de encéfalo muestra cambios en los tres indicadores utilizados. CONCLUSIONES: Es necesario realizar un análisis de las tasas específicas por edad antes de proceder a su ajuste. Este análisis permite averiguar si el ajuste por edades es correcto y qué indicador (diferencia, razón o cambio porcentual será adecuado para realizar comparaciones.

  6. Aquaporins: highly regulated channels controlling plant water relations.

    Science.gov (United States)

    Chaumont, François; Tyerman, Stephen D

    2014-04-01

    Plant growth and development are dependent on tight regulation of water movement. Water diffusion across cell membranes is facilitated by aquaporins that provide plants with the means to rapidly and reversibly modify water permeability. This is done by changing aquaporin density and activity in the membrane, including posttranslational modifications and protein interaction that act on their trafficking and gating. At the whole organ level aquaporins modify water conductance and gradients at key "gatekeeper" cell layers that impact on whole plant water flow and plant water potential. In this way they may act in concert with stomatal regulation to determine the degree of isohydry/anisohydry. Molecular, physiological, and biophysical approaches have demonstrated that variations in root and leaf hydraulic conductivity can be accounted for by aquaporins but this must be integrated with anatomical considerations. This Update integrates these data and emphasizes the central role played by aquaporins in regulating plant water relations.

  7. Computational Fluid Dynamics Simulation Study of Active Power Control in Wind Plants

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, Paul; Aho, Jake; Gebraad, Pieter; Pao, Lucy; Zhang, Yingchen

    2016-08-01

    This paper presents an analysis performed on a wind plant's ability to provide active power control services using a high-fidelity computational fluid dynamics-based wind plant simulator. This approach allows examination of the impact on wind turbine wake interactions within a wind plant on performance of the wind plant controller. The paper investigates several control methods for improving performance in waked conditions. One method uses wind plant wake controls, an active field of research in which wind turbine control systems are coordinated to account for their wakes, to improve the overall performance. Results demonstrate the challenge of providing active power control in waked conditions but also the potential methods for improving this performance.

  8. Plant traits and plant biogeography control the biotic resistance provided by generalist herbivores

    NARCIS (Netherlands)

    Grutters, B.M.C.; Roijendijk, Yvonne; Verberk, W.C.E.P.; Bakker, E.S.

    2017-01-01

    1.Globalization and climate change trigger species invasions and range shifts, which reshuffle communities at an exceptional rate and expose plant migrants to unfamiliar herbivores. Dominant hypotheses to predict plant success are based on evolutionary novelty: either herbivores are maladapted to

  9. Application of NASA-developed technology to the automatic control of municipal sewage treatment plants

    Science.gov (United States)

    Hiser, L. L.; Herrera, W. R.

    1973-01-01

    A search was made of NASA developed technology and commercial technology for process control sensors and instrumentation which would be applicable to the operation of municipal sewage treatment plants. Several notable items were found from which process control concepts were formulated that incorporated these items into systems to automatically operate municipal sewage treatment plants. A preliminary design of the most promising concept was developed into a process control scheme for an activated sludge treatment plant. This design included process control mechanisms for maintaining constant food to sludge mass (F/M) ratio, and for such unit processes as primary sedimentation, sludge wastage, and underflow control from the final clarifier.

  10. Metabolic Engineering of Chemical Defence Pathways in Plant Disease Control

    DEFF Research Database (Denmark)

    Rook, Frederik

    2016-01-01

    Plants produce a wide variety of specialized (or secondary) metabolites that function as chemical defence compounds and provide protection against microbial pathogens or herbivores. This chapter focuses on the metabolic engineering of biosynthetic pathways for plant chemical defence compounds...... with antimicrobial properties for use in crop protection. It presents an overview of the metabolic engineering efforts made in the area of plant chemical defence. For in-depth information on the characteristics of a specific class of chemical defence compounds, the reader is referred to the specialized reviews...

  11. Distributed Low-Complexity Controller for Wind Power Plant in Derated Operation

    DEFF Research Database (Denmark)

    Biegel, Benjamin; Madjidian, Daria; Spudic, Vedrana;

    2013-01-01

    We consider a wind power plant of megawatt wind turbines operating in derated mode. When operating in this mode, the wind power plant controller is free to distribute power set-points to the individual turbines, as long as the total power demand is met. In this work, we design a controller...

  12. Model-Free Adaptive Switching Control of Time-Varying Plants

    NARCIS (Netherlands)

    Battistelli, Giorgio; Hespanha, João P.; Mosca, Edoardo; Tesi, Pietro

    2013-01-01

    This paper addresses the problem of controlling an uncertain time-varying plant by means of a finite family of candidate controllers supervised by an appropriate switching logic. It is assumed that, at every time, the plant consists of an uncertain single-input/single output linear system. It is sho

  13. Fuzzy-logic approach to HTR nuclear power plant model control

    Energy Technology Data Exchange (ETDEWEB)

    Bubak, M.; Moscinski, J. (Akademia Gorniczo-Hutnicza, Krakow (Poland)); Jewulski, J. (Institute of Physical Chemistry, Krakow (Poland))

    1983-01-01

    The fuzzy-set theory is used to incorporate linguistic 'rules of the thumb' of a human operator in the HTR nuclear power plant controller. The results of the extensive computer simulations are encouraging and confirm the usefulness of this approach in nuclear power plant control. In the Appendix, a short introduction to fuzzy logic is given.

  14. Using H∞ to design robust POD controllers for wind power plants

    DEFF Research Database (Denmark)

    Mehmedalic, Jasmin; Knüppel, Thyge; Østergaard, Jacob

    2012-01-01

    Large wind power plants (WPPs) can help to improve small signal stability by increasing the damping of electromechanical modes of oscillation. This can be done by adding a power system oscillation damping (POD) controller to the wind power plants, similar to power system stabilizer (PSS) controll...

  15. Plant management in natural areas: balancing chemical, mechanical, and cultural control methods

    Science.gov (United States)

    Steven Manning; James. Miller

    2011-01-01

    After determining the best course of action for control of an invasive plant population, it is important to understand the variety of methods available to the integrated pest management professional. A variety of methods are now widely used in managing invasive plants in natural areas, including chemical, mechanical, and cultural control methods. Once the preferred...

  16. Stability Analysis of DC-link Voltage Control on Autonomous Micro Hydro Power Plant System

    OpenAIRE

    Feri Yusivar; M. Shanizal; A. Subiantoro; Gunawan, R

    2014-01-01

    Micro Hydro Power Plant has become one of the interesting topics to be researched nowadays. This paper deals with the stability analysis on control system of excitation voltage in Micro Hydro Power Plant. The control of this voltage can be achieved by controlling the Permanent Magnet Synchronous Machine (PMSM) with particular algorithm so the voltage on the DC-link part of the system can be controlled. Without knowing the exact specification of system parameters, the system will be most likel...

  17. La influencia de las diferencias entre el padre y la madre sobre el ajuste adolescente

    Directory of Open Access Journals (Sweden)

    Antonia Jiménez-Iglesias

    2015-01-01

    Full Text Available Este trabajo se centra en analizar cómo influyen en el consumo de sustancias (tabaco, alcohol y cannabis y el bienestar psicológico adolescente (calidad de vida relacionada con la salud y satisfacción vital las diferencias entre el padre y la madre en afecto, promoción de la autonomía, revelación, interés y conocimiento. La muestra estuvo compuesta por 10170 chicos y chicas españoles de 13 a 18 años de familias biparentales que participaron en la edición 2006 del estudio Health Behaviour in School-aged Children (HBSC. Los resultados mostraron que los adolescentes que indicaron que su padre y madre coincidían en presentar altos niveles en las dimensiones familiares analizadas consumieron menos sustancias y tuvieron mejor bienestar psicológico. Por el contrario, el ajuste de los adolescentes cuyos progenitores (padre y madre tenían bajos niveles en esas dimensiones familiares fue peor. Concretamente, la dimensión más importante para el consumo de sustancias fue el conocimiento parental y para el bienestar psicológico lo fue el afecto parental; la revelación adolescente solo fue relevante para el consumo de alcohol y la calidad de vida, mientras que la promoción parental de la autonomía lo fue para la calidad de vida.

  18. Elementos para el análisis de los programas de ajuste

    Directory of Open Access Journals (Sweden)

    Villamizar Helena

    1991-12-01

    Full Text Available

    La aplicación de las políticas generales, preconizadas por los programas de ajuste en América Latina, en la mayoría de los casos no dieron los resultados deseados. Su éxito necesariamente requería del cumplimiento de ciertos supuestos y condiciones que permitieran que las políticas de "gestión de demanda no generaran efectos negativos sobre el crecimiento en el largo plazo. Al no cumplirse algunos de 105 supuestos teóricos básicos, y al no contar los países con flujos de capitales adecuados y con un entorno externo abierto, la aplicación de estos programas se tradujo en grandes sacrificios en el crecimiento y muchas veces en la perpetuación de situaciones recesivas. Puesto que la región aun no ha encontrado una verdadera vía de solución, se hace imperioso abordar la construcción de una nueva perspectiva teórica, basada en supuestos realistas, que permita abordar los apremiantes problemas del desarrollo latinoamericano.

  19. O dia seguinte: as credenciais da sobrevivência ao ajuste nas empresas

    Directory of Open Access Journals (Sweden)

    Guimarães Nadya Araujo

    1999-01-01

    Full Text Available O artigo tem por objetivo refletir sobre os nexos entre seletividade ocupacional e requerimentos de qualificação numa conjuntura de intensa reestruturação industrial. Para tanto, procura responder duas questões. Primeira: quem tem sobrevivido ao ajuste ocorrido no mercado de trabalho industrial no Brasil dos anos 90? Isto é, que credenciais de qualificação permitiram tal sobrevivência? Segunda: qual o tipo de inserção oferecida aos que lograram permanecer integrados a estas indústrias? Isto é, em que tipo de postos de trabalho sobreviveram tais trabalhadores remanescentes? Para ilustrar a análise, toma-se em consideração um segmento especial - a indústria química - exemplar pelas intensas mudanças que sofreu nos anos 90 e também pela prévia e elevada seletividade de seus critérios de recrutamento. A análise empírica se baseia em estatísticas do Ministério do Trabalho (Rais-Caged.

  20. Dynamic Modeling and Control Characteristics of the Two-Modular HTR-PM Nuclear Plant

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2017-01-01

    Full Text Available The modular high temperature gas-cooled reactor (MHTGR is a typical small modular reactor (SMR with inherent safety feature. Due to its high reactor outlet coolant temperature, the MHTGR can be applied not only for electricity production but also as a heat source for industrial complexes. Through multimodular scheme, that is, the superheated steam flows produced by multiple MHTGR-based nuclear supplying system (NSSS modules combined together to drive a common thermal load, the inherent safety feature of MHTGR is applicable to large-scale nuclear plants at any desired power ratings. Since the plant power control technique of traditional single-modular nuclear plants cannot be directly applied to the multimodular plants, it is necessary to develop the power control method of multimodular plants, where dynamical modeling, control design, and performance verification are three main aspects of developing plant control method. In this paper, the study in the power control for two-modular HTR-PM plant is summarized, and the verification results based on numerical simulation are given. The simulation results in the cases of plant power step and ramp show that the plant control characteristics are satisfactory.

  1. Ajuste al rol de género en mujeres con y sin trastornos de la conducta alimentaria

    OpenAIRE

    2014-01-01

    Los trastornos de la conducta alimentaria podrían estar relacionados con el ajuste al rol de género de quienes los padecen, es decir, con la distancia percibida entre las características que se acepta poseer y aquellas que conforman el ideal personal. Por tal motivo, con el fin de indagar si el ajuste al rol de género guarda relación con aquéllos, se evaluaron la autopercepción y el ideal del rol de género en una muestra de 154 mujeres con edades de entre 14 y 30 años, de las cuales 49 padecí...

  2. Teoría de las Contingencias Múltiples Dinámicamente Entrelazadas (Abriendo la caja negra del ajuste contingente

    Directory of Open Access Journals (Sweden)

    Lic. Jorge Washington Barrientos

    2013-12-01

    Full Text Available La teoría de las contingencias ha ocupado un rol destacado en el estudio del diseño de las estructuras organizacionales en los últimos cincuenta años. Sus contribuciones se han dirigido en distintas direcciones, una de ellas ha sido enumeración de factores de contingencia y la posterior identificación de relaciones entre estos y los elementos estructurales.Refinamientos posteriores han conceptualizado la respuesta sistémica que permite el ajuste (“fit” de la organización a los cambios en los factores de contingencia.Este trabajo se propone repasar críticamente las principales conceptualizaciones del ajuste estructural, y a la vez proponer una nueva variable interviniente en el marco de una teoría de contingencias múltiples dinámicamente entrelazadas.

  3. Lucha popular, democracia, neoliberalismo: protesta popular en América Latina en los años del ajuste

    Directory of Open Access Journals (Sweden)

    Martha Cecilia García V.

    2010-08-01

    Full Text Available Margarita López Maya (editora. Lucha popular, democracia, neoliberalismo: protesta popular en América Latina en los años del ajuste. Caracas: Nueva Sociedad, 1999, 264 páginas. Este libro presenta una compilación de diez artículos elaborados por investigadores de Argentina, México, Colombia, Guatemala, Brasil, República Dominicana y Venezuela, producto de sus investigaciones sobre luchas y movimientos sociales en estos países. La intención del libro, según la compiladora, es tratar de llegar de manera conjunta a algunas hipótesis sobre los procesos de protesta y sus relaciones con el neoliberalismo y descubrir el modo en que los sectores más golpeados en sus expectativas y condiciones de vida por las políticas de ajuste han comenzado a demandar sus derechos.

  4. Lucha popular, democracia, neoliberalismo: protesta popular en América Latina en los años del ajuste

    Directory of Open Access Journals (Sweden)

    Martha Cecilia García V.

    2000-01-01

    Full Text Available Margarita López Maya (editora. Lucha popular, democracia, neoliberalismo: protesta popular en América Latina en los años del ajuste. Caracas: Nueva Sociedad, 1999, 264 páginas. Este libro presenta una compilación de diez artículos elaborados por investigadores de Argentina, México, Colombia, Guatemala, Brasil, República Dominicana y Venezuela, producto de sus investigaciones sobre luchas y movimientos sociales en estos países. La intención del libro, según la compiladora, es tratar de llegar de manera conjunta a algunas hipótesis sobre los procesos de protesta y sus relaciones con el neoliberalismo y descubrir el modo en que los sectores más golpeados en sus expectativas y condiciones de vida por las políticas de ajuste han comenzado a demandar sus derechos.

  5. Coefficient d'ajustement pour des processus de risque dans des contextes de dépendance

    OpenAIRE

    Cossette, Hélène; Marceau, Etienne; Maume-Deschamps, Véronique

    2009-01-01

    International audience; Nous étudions le coefficient d'ajustement de la théorie de la ruine dans un contexte de dépendance temporelle. Le coefficient d'ajustement, pour des données indépendantes a étudié par de nombreux auteurs. Nous utilisons ici la définition de Müller et Pflug pour des variables dépendantes. Nous construisons un estimateur consitant de ce coefficient dans un cadre de dépendance faible général. Pour des cas particuliers ayant un sens en théorie de la ruine / actuariat, nous...

  6. Avaliação das dimensões programáveis dos articuladores semi-ajustáveis

    OpenAIRE

    GRECO, Gustavo Diniz; Fialho, Denise Ligório; Lana, Ana Cláudia Carvalho; Jansen,Wellington Corrêa

    2016-01-01

    O articulador semi-ajustável tem o propósito de reproduzir as relações maxilomandibulares estáticas e, parcialmente, as dinâmicas. No entanto, parte destas características depende da qualidade da fabricação dos aparelhos. O objetivo foi aferir os componentes responsáveis pela determinação do ângulo de Bennett (AB), da eminência articular (EA) e da distância intercondilar (DI) do articulador semi-ajustável (ASA) Dentflex®. A amostra constituiu-se de 30 ASA novos dos alunos da Pontifícia Univer...

  7. Palmyra Atoll - Invasive Plant Management: Eradicate/Control 2010

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Remote atoll ecosystems are havens of biological diversity, but vulnerable to ecological invasion. The prosperity of the plants and animals that inhabit remote atoll...

  8. Palmyra Atoll - Invasive Plant Management: Eradicate/Control 2013

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Remote atoll ecosystems are havens of biological diversity, but vulnerable to ecological invasion. The prosperity of the plants and animals that inhabit remote atoll...

  9. Palmyra Atoll - Invasive Plant Management: Eradicate/Control 2012

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Remote atoll ecosystems are havens of biological diversity, but vulnerable to ecological invasion. The prosperity of the plants and animals that inhabit remote atoll...

  10. Hazard Identification, Risk Assessment and Risk Control (HIRARC Accidents at Power Plant

    Directory of Open Access Journals (Sweden)

    Ahmad Asmalia Che

    2016-01-01

    Full Text Available Power plant had a reputation of being one of the most hazardous workplace environments. Workers in the power plant face many safety risks due to the nature of the job. Although power plants are safer nowadays since the industry has urged the employer to improve their employees’ safety, the employees still stumble upon many hazards thus accidents at workplace. The aim of the present study is to investigate work related accidents at power plants based on HIRARC (Hazard Identification, Risk Assessment and Risk Control process. The data were collected at two coal-fired power plant located in Malaysia. The finding of the study identified hazards and assess risk relate to accidents occurred at the power plants. The finding of the study suggested the possible control measures and corrective actions to reduce or eliminate the risk that can be used by power plant in preventing accidents from occurred

  11. Consumo de sustancias durante la adolescencia:trayectorias evolutivas y consecuencias para el ajuste psicológico

    OpenAIRE

    Alfredo Oliva; Águeda Parra; Inmaculada Sánchez-Queija

    2008-01-01

    Este estudio ha perseguido dos objetivos fundamentales: encontrar diferentes trayectorias en el consumo de sustancias a lo largo de la adolescencia y analizar las consecuencias que este consumo en la adolescencia temprana y media tiene para el ajuste emocional y comportamental al final de la adolescencia. El estudio, con un diseño descriptivo longitudinal mediante cuestionarios, se llevó a cabo sobre una muestra de 101 adolescentes (63 varones y 38 mujeres) que fueron estudiados en 3 ocasione...

  12. Inteligência emocional percebida (IEP) ajuste emocional e actividade física na terceira idade

    OpenAIRE

    2007-01-01

    O interesse deste estudo está centrado na forma como interage a inteligência emocional percebida (IEP) com a prática da actividade física e que peso específi co tem cada uma das variáveis estudadas sobre o ajuste emocional das pessoas nesta faixa etária e, consequentemente, na sua qualidade de vida.

  13. Resource availability controls fungal diversity across a plant diversity gradient

    Science.gov (United States)

    Waldrop, M.P.; Zak, D.R.; Blackwood, C.B.; Curtis, C.D.; Tilman, D.

    2006-01-01

    Despite decades of research, the ecological determinants of microbial diversity remain poorly understood. Here, we test two alternative hypotheses concerning the factors regulating fungal diversity in soil. The first states that higher levels of plant detritus production increase the supply of limiting resources (i.e. organic substrates) thereby increasing fungal diversity. Alternatively, greater plant diversity increases the range of organic substrates entering soil, thereby increasing the number of niches to be filled by a greater array of heterotrophic fungi. These two hypotheses were simultaneously examined in experimental plant communities consisting of one to 16 species that have been maintained for a decade. We used ribosomal intergenic spacer analysis (RISA), in combination with cloning and sequencing, to quantify fungal community composition and diversity within the experimental plant communities. We used soil microbial biomass as a temporally integrated measure of resource supply. Plant diversity was unrelated to fungal diversity, but fungal diversity was a unimodal function of resource supply. Canonical correspondence analysis (CCA) indicated that plant diversity showed a relationship to fungal community composition, although the occurrence of RISA bands and operational taxonomic units (OTUs) did not differ among the treatments. The relationship between fungal diversity and resource availability parallels similar relationships reported for grasslands, tropical forests, coral reefs, and other biotic communities, strongly suggesting that the same underlying mechanisms determine the diversity of organisms at multiple scales. ?? 2006 Blackwell Publishing Ltd/CNRS.

  14. Nonlinear continuous-time generalized predictive control of solar power plant

    Directory of Open Access Journals (Sweden)

    Khoukhi Billal

    2015-01-01

    Full Text Available This paper presents an application of nonlinear continuous-time generalized predictive control (GPC to the distributed collector field of a solar power plant. The major characteristic of a solar power plant is that the primary energy source, solar radiation, cannot be manipulated. Solar radiation varies throughout the day, causing changes in plant dynamics and strong perturbations in the process. A brief description of the solar power plant and its simulator is given. After that, basic concepts of predictive control and continuous-time generalized predictive control are introduced. A new control strategy, named nonlinear continuous-time generalized predictive control (NCGPC, is then derived to control the process. The simulation results show that the NCGPC gives a greater flexibility to achieve performance goals and better perturbation rejection than classical control.

  15. Development of Information Processing and the Network System for the Control and Management of Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Hee; Park, Doo Young; Woo, Joo Hee [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Kwon, Wook Hyun; Park, Jeong Woo; Moon, Hong Joo; Moon, Sang Yong [Seoul National University, Seoul (Korea, Republic of)

    1996-12-31

    It is needed to supervise, control and manage the inter operation of the system that is connected together to achieve good operation and high performance of the power plant. Moreover, the interconnection of the power plant is indispensable and they must be managed together. At present the control management systems that are on operation at power plants are composed of various systems from different companies, and the power plants have their own structure, we have much difficulty in managing communication of the systems. So, this study suggests the standard specification of the communication network for power plants. We have developed the network hardware, the 7 layers UCA, the network application software, the gateway between 3 layers UCA and the 7 layers UCA. Finally, we have developed the interface to Infi`90 which is one of the most popularly used system for power plant control, so that PC can be used for the operation of Infi`90. (author). 82 refs., figs.

  16. ESTRATEGIAS DE AJUSTE ANTE CHOQUES HIPOTÉTICOS DE OFERTA Y DEMANDA. Resultados de una encuesta a empresas mexicanas

    Directory of Open Access Journals (Sweden)

    Paula Sánchez-Romeu

    2015-01-01

    Full Text Available En este artículo se analizan estrategias de ajuste para hacer frente a choques hipotéticos de oferta y demanda utilizadas por 1 138 empresas mexicanas encuestadas por el Banco de México en 2012. Los resultados del análisis muestran que la respuesta de las empresas ante los dos tipos de choque en general no es simétrica y que éstas reaccionan combinando estrategias (principalmente eligen reducir costos, con lo cual moderan los ajustes a precios y producción. Más competencia hace que las empresas utilicen con más intensidad las estrategias de ajuste y favorece la flexibilidad de los precios. Ante cualquier choque, los costos que más se reducen son los no laborales y los que genera el empleo temporal. Una alta competencia y un mayor porcentaje de costos laborales intensifican el traspaso de los choques al empleo; por el contrario, los acuerdos colectivos de trabajo mitigan dicho traspaso. No se observa un traspaso de los choques a las percepciones salariales, lo cual, aunado a la baja incidencia de la reducción del salario base, evidencia rigidez en los salarios nominales de las empresas entrevistadas.

  17. Aquatic Plant Control Research Program: Effects of Water Chemistry on Submersed Aquatic Plants: A Synthesis

    Science.gov (United States)

    1990-07-01

    plants exhibiting C4 photosynthesis, C is conserved by refixing photorespired CO2. These terres- trial adaptations have counterparts in the aquatic...such as low photorespiration rates and low CO2 compensation points. The advantages of this photosynthetic pathway include conservation of... photorespired C and efficient C assimilation under the high dissolved oxygen and low free CO2 concentrations common in dense submersed aquatic plant populations

  18. Molecular Approach to the Nyctinastic Movement of the Plant Controlled by a Biological Clock

    Directory of Open Access Journals (Sweden)

    Shosuke Yamamura

    2001-10-01

    Full Text Available Most leguminous plants close their leaves in the evening, as if to sleep, and open them early in the morning. This circadian rhythm is known to be controlled by the biological clock of such plants. Extensive studies on other nyctinastic plants led to the isolation of a variety of leaf-closing and leaf-opening substances. And, we found that the circadian rhythmic leaf-movement of these plants is controlled by a biological clock that regulates the balance of concentration between leaf-opening and -closing substances.

  19. Molecular Approach to the Nyctinastic Movement of the Plant Controlled by a Biological Clock

    OpenAIRE

    Shosuke Yamamura; Noboru Takada; Minoru Ueda

    2001-01-01

    Most leguminous plants close their leaves in the evening, as if to sleep, and open them early in the morning. This circadian rhythm is known to be controlled by the biological clock of such plants. Extensive studies on other nyctinastic plants led to the isolation of a variety of leaf-closing and leaf-opening substances. And, we found that the circadian rhythmic leaf-movement of these plants is controlled by a biological clock that regulates the balance of concentration between leaf-opening a...

  20. A plant-specific cyclin-dependent kinase is involved in the control of G2/M progression in plants.

    Science.gov (United States)

    Porceddu, A; Stals, H; Reichheld, J P; Segers, G; De Veylder, L; Barroco, R P; Casteels, P; Van Montagu, M; Inzé, D; Mironov, V

    2001-09-28

    Cyclin-dependent kinases (CDKs) control the key transitions in the eukaryotic cell cycle. All the CDKs known to control G(2)/M progression in yeast and animals are distinguished by the characteristic PSTAIRE motif in their cyclin-binding domain and are closely related. Higher plants contain in addition a number of more divergent non-PSTAIRE CDKs with still obscure functions. We show that a plant-specific type of non-PSTAIRE CDKs is involved in the control of the G(2)/M progression. In synchronized tobacco BY-2 cells, the corresponding protein, accumulated in a cell cycle-regulated fashion, peaking at the G(2)/M transition. The associated histone H1 kinase activity reached a maximum in mitosis and required a yet unidentified subunit to be fully active. Down-regulation of the associated kinase activity in transgenic tobacco plants using a dominant-negative mutation delayed G(2)/M transition. These results provide the first evidence that non-PSTAIRE CDKs are involved in the control of the G(2)/M progression in plants.

  1. Widespread mechanosensing controls the structure behind the architecture in plants.

    Science.gov (United States)

    Hamant, Olivier

    2013-10-01

    Mechanical forces play an instructing role for many aspects of animal cell biology, such as division, polarity and fate. Although the associated mechanoperception pathways still remain largely elusive in plants, physical cues have long been thought to guide development in parallel to biochemical factors. With the development of new imaging techniques, micromechanics tools and modeling approaches, the role of mechanical signals in plant development is now re-examined and fully integrated with modern cell biology. Using recent examples from the literature, I propose to use a multiscale perspective, from the whole plant down to the cell wall, to fully appreciate the diversity of developmental processes that depend on mechanical signals. Incidentally, this also illustrates how conceptually rich this field is.

  2. The role of plant-microbiome interactions in weed establishment and control.

    Science.gov (United States)

    Trognitz, Friederike; Hackl, Evelyn; Widhalm, Siegrid; Sessitsch, Angela

    2016-10-01

    The soil microbiome plays an important role in the establishment of weeds and invasive plants. They associate with microorganisms supporting their growth and health. Weed management strategies, like tillage and herbicide treatments, to control weeds generally alter soil structure going alongside with changes in the microbial community. Once a weed population establishes in the field, the plants build up a close relationship with the available microorganisms. Seeds or vegetative organs overwinter in soil and select early in the season their own microbiome before crop plants start to vegetate. Weed and crop plants compete for light, nutrition and water, but may differently interact with soil microorganisms. The development of new sequencing technologies for analyzing soil microbiomes has opened up the possibility for in depth analysis of the interaction between 'undesired' plants and crop plants under different management systems. These findings will help us to understand the functions of microorganisms involved in crop productivity and plant health, weed establishment and weed prevention. Exploitation of the knowledge offers the possibility to search for new biocontrol methods against weeds based on soil and plant-associated microorganisms. This review discusses the recent advances in understanding the functions of microbial communities for weed/invasive plant establishment and shows new ways to use plant-associated microorganisms to control weeds and invasive plants in different land management systems.

  3. Plant natriuretic peptides control of synthesis and systemic effects

    KAUST Repository

    Wang, Yuhua

    2011-10-01

    Plant natriuretic peptides (PNPs) are signaling molecules that are secreted into the apoplast particularly under conditions of biotic and abiotic stress. At the local level, PNPs modulate their own expression via feed forward and feedback loops to enable tuning of the response at the transcript and protein level and to prevent overexpression. PNPs also employ a systemic signal, possibly electrical, to rapidly alter photosynthesis and respiration not only in treated leaves but also in upper and lower leaves thereby modulating and integrating physiological responses at the level of the whole plant. © 2011 Landes Bioscience.

  4. Development of design support tool using integrated hierarchical control chart (HCC) and IEC61131 for nuclear power plant control

    Energy Technology Data Exchange (ETDEWEB)

    Nasimi, E.; Gabbar, H.A. [Univ. of Ontario Inst. of Tech., Oshawa, Ontario (Canada)

    2009-07-01

    This paper proposes a new intelligent and highly automated Hierarchical Control Chart (HCC) and operations mapping solution for nuclear power plant operators that provides control system designers, developers and operators with a single view of all elements and systems across a power plant with the integrated interactive data access and information retrieval capabilities that enables a faster fault diagnostics as well aids in a more efficient decision making for the routine daily tasks. (author)

  5. DSC: software tool for simulation-based design of control strategies applied to wastewater treatment plants.

    Science.gov (United States)

    Ruano, M V; Ribes, J; Seco, A; Ferrer, J

    2011-01-01

    This paper presents a computer tool called DSC (Simulation based Controllers Design) that enables an easy design of control systems and strategies applied to wastewater treatment plants. Although the control systems are developed and evaluated by simulation, this tool aims to facilitate the direct implementation of the designed control system to the PC of the full-scale WWTP (wastewater treatment plants). The designed control system can be programmed in a dedicated control application and can be connected to either the simulation software or the SCADA of the plant. To this end, the developed DSC incorporates an OPC server (OLE for process control) which facilitates an open-standard communication protocol for different industrial process applications. The potential capabilities of the DSC tool are illustrated through the example of a full-scale application. An aeration control system applied to a nutrient removing WWTP was designed, tuned and evaluated with the DSC tool before its implementation in the full scale plant. The control parameters obtained by simulation were suitable for the full scale plant with only few modifications to improve the control performance. With the DSC tool, the control systems performance can be easily evaluated by simulation. Once developed and tuned by simulation, the control systems can be directly applied to the full-scale WWTP.

  6. Synthesis of Model Based Robust Stabilizing Reactor Power Controller for Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    Arshad Habib Malik

    2011-04-01

    Full Text Available In this paper, a nominal SISO (Single Input Single Output model of PHWR (Pressurized Heavy Water Reactor type nuclear power plant is developed based on normal moderator pump-up rate capturing the moderator level dynamics using system identification technique. As the plant model is not exact, therefore additive and multiplicative uncertainty modeling is required. A robust perturbed plant model is derived based on worst case model capturing slowest moderator pump-up rate dynamics and moderator control valve opening delay. Both nominal and worst case models of PHWR-type nuclear power plant have ARX (An Autoregressive Exogenous structures and the parameters of both models are estimated using recursive LMS (Least Mean Square optimization algorithm. Nominal and worst case discrete plant models are transformed into frequency domain for robust controller design purpose. The closed loop system is configured into two port model form and H? robust controller is synthesized. The H?controller is designed based on singular value loop shaping and desired magnitude of control input. The selection of desired disturbance attenuation factor and size of the largest anticipated multiplicative plant perturbation for loop shaping of H? robust controller form a constrained multi-objective optimization problem. The performance and robustness of the proposed controller is tested under transient condition of a nuclear power plant in Pakistan and found satisfactory.

  7. Towards automatic model based controller design for reconfigurable plants

    DEFF Research Database (Denmark)

    Michelsen, Axel Gottlieb; Stoustrup, Jakob; Izadi-Zamanabadi, Roozbeh

    2008-01-01

    This paper introduces model-based Plug and Play Process Control, a novel concept for process control, which allows a model-based control system to be reconfigured when a sensor or an actuator is plugged into a controlled process. The work reported in this paper focuses on composing a monolithic m...

  8. Temporal variation in plant-soil feedback controls succession

    NARCIS (Netherlands)

    Kardol, P.; Bezemer, T.M.; Putten, van der W.H.

    2006-01-01

    Soil abiotic and biotic factors play key roles in plant community dynamics. However, little is known about how soil biota influence vegetation changes over time. Here, we show that the effects of soil organisms may depend on both the successional development of ecosystems and on the successional pos

  9. Application of optical controlling methods for plants under external influence

    Science.gov (United States)

    Timchenko, E. V.; Taskina, L. A.

    2012-10-01

    The experimental study results of spectral characteristic change of different types of plants influenced by external factors (synthetic superficially active substances, salts of heavy metals and nitrate fertilizers) are presented. Differential optical factor was used as the monitored optical parameter that characterizes the chlorophyll concentration change. The differential backscatter method which has high test-sensitivity and provides with the most complete information on the plant condition was the main optical monitoring method. For understanding the mechanisms of external factor accumulation and influence on plants the confocal fluorescent microscopy method providing contrast micrographs of high resolution was used for microscopic analysis in the study. It was revealed that synthetic superficially active substances and heavy metal presence lead to quasilinear decrease of differential backscatter factor with time. It was shown that the presence of salts of heavy metals in a water solution leads to chlorophyll "binding" which is microscopically shown as their «adhesion» near the cell membranes. On the contrary, the presence of synthetic superficially active substances maintains the uniformity of chlorophyll distribution in a cell, but its concentration falls with increasing the concentration in a major emission. The latter depends on the fact that synthetic superficially active substances solubilize the cell membrane proteins, increasing its penetrability. It causes pigment release ("washing away") from a plant, thereby leading to differential optical factor change. It was shown that nitrate fertilizer presence leads to increase of differential backscatter factor with time which is microscopically connected to increase in chlorophyll concentration.

  10. Managing invasive plants in natural areas: Moving beyond weed control

    Science.gov (United States)

    Dean Pearson; Yvette Ortega

    2009-01-01

    Exotic invasive plants present one of the greatest challenges to natural resource management. These weeds can alter entire communities and ecosystems, substantially degrading important ecosystem services such as forage for wild and domestic herbivores, water and soil quality, recreational values, and wildlife habitat. Traditionally, weed management in natural areas has...

  11. Regulation of transcription in plants: mechanisms controlling developmental switches.

    NARCIS (Netherlands)

    Kaufmann, K.; Pajoro, A.; Angenent, G.C.

    2010-01-01

    Unlike animals, plants produce new organs throughout their life cycle using pools of stem cells that are organized in meristems. Although many key regulators of meristem and organ identities have been identified, it is still not well understood how they function at the molecular level and how they c

  12. Alternative food promotes broad mite control on chilli pepper plants

    NARCIS (Netherlands)

    Duarte, M.V.A.; Venzon, M.; de S. Bittencourt, M.C.; Rodríguez-Cruz, F.A.; Pallini, A.; Janssen, A.

    2015-01-01

    Many omnivorous arthropods are important natural enemies because they can feed on plant-provided pollen and several prey species, and thus persist in crops even in the absence of the target pest. Hence, populations of these predators can be established in a crop by providing alternative food, thus

  13. Alternative food promotes broad mite control on chilli pepper plants

    NARCIS (Netherlands)

    Duarte, M.V.A.; Venzon, M.; de S. Bittencourt, M.C.; Rodríguez-Cruz, F.A.; Pallini, A.; Janssen, A.

    2015-01-01

    Many omnivorous arthropods are important natural enemies because they can feed on plant-provided pollen and several prey species, and thus persist in crops even in the absence of the target pest. Hence, populations of these predators can be established in a crop by providing alternative food, thus i

  14. Control of plant architecture by distinctive TALE homeobox gene interactions

    NARCIS (Netherlands)

    Bao, D.

    2009-01-01

    In eukaryotes, transcription factor (TF)-based network is a widely used mechanism to regulate fundamental developmental processes. Both animals and plants utilize three-amino-acid-loop-extension (TALE) homeodomain (HD) transcription factors to subdivide their body plan. In animals, MEIS/PBC TF heter

  15. Plant tolerance: A unique approach to control hemipteran pests

    Science.gov (United States)

    Plant tolerance to insect pests has been indicated to be a unique category of resistance, however, very little information is available on the mechanism of tolerance against insect pests. Tolerance is distinctive in terms of the plant’s ability to withstand or recover from herbivore injury through g...

  16. Biodiversity in agricultural soils, sustainable plant production and control of plant pathogens

    Directory of Open Access Journals (Sweden)

    A. J. Reinecke

    2010-01-01

    Full Text Available Pathogens Soils are very heterogeneous substrates providing an environmental matrix with varying spatial and temporal gradients of pH, organic carbon, particle size distribution and moisture content. Chemical, physical as well as biological factors are operational and soil includes a vast variety of soil-dwelling invertebrates and microbes that interact with each other and the environment to influence plant productivity directly and indirectly. A review of recent literature on the role of soil biodiversity highlights the important role of soil invertebrates, notably earthworms, in influencing soil characteristics and soil borne plant pathogens. Earthworms are widely recognized as having critical functions in soil in regulating key processes that impact favourably on plant productivity and simultaneously eliminating or reducing soil borne diseases. The aim of this review is firstly to contribute towards a clarification of the role of soil biodiversity in general and to focus specifically on that of earthworms and their role in influencing plant pathogens and parasites. Evidence is provided that their activities can support plant productivity and suppress pathogens. Once the nature and extent of their role is better known and they are confirmed to support plant productivity to the extent that many soil biologists believe, the next logical step is to utilize knowledge of their ecology to create and manage favourable environmental conditions to ensure their survival and activity in agricultural soils. Agricultural management practices that favour soil organisms are also reviewed. Implementing these will make the services of soil biota available to improve and sustain agro-ecosystems. This requires a better understanding of the preferences and tolerance ranges of these organisms and their interactions before we can apply methodologies in general to manipulate environmental conditions to maximise the benefits that they may offer.

  17. Application of some insecticides and plant crude extracts for controlling insect pests in yard long bean

    OpenAIRE

    2003-01-01

    Tests on plant crude extracts of neem seeds, galanga and citronella grass at the rates of 200 ml/20 L of water together with synthetic insecticides, cypermethrin, methamidophos, carbosulfan and carbofuran, at the recommended rates showed that none of the treatments was effective in controlling plant damage caused by adult of bean fly (Ophiomyia phaseoli Tryon). The application of the synthetic insecticide, methamidophos, and plant crude extracts of neem seeds + galanga + citronella grass prov...

  18. Identification and Control of Nutrient Removing Processes in Wastewater Treatment Plants

    DEFF Research Database (Denmark)

    Nielsen, Marinus K.; Madsen, Henrik; Carstensen, Niels Jacob

    1994-01-01

    Today the use of on-line control for wastewater treatment plants is very low. A main reason is the lack of quality of the data, and the fact that more sophisticated control strategies must be based on a model of the dynamics of the biological processes. This paper discusses the historical reasons...... for the limited use of modern control strategies for wastewater treatment plants. Today, however, on-line nutrient sensors are more reliable. In the present context the use of on-line monitored values of ammonia, nitrate and phosphate from a full scale plant are used as the background for discussing...

  19. Complexity of nutrient use efficiency in plants : Metabolic and environmental control at a whole plant perspective

    NARCIS (Netherlands)

    Reich, Martin

    2015-01-01

    To meet the increasing demand for food of a fast growing world population, agriculture needs to be more productive. During last century the agricultural production was worldwide strongly improved by plant breeding and the use of pesticides and fertilizers. This has also resulted in negative environm

  20. Optimal control system design for IGCC power plants with CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.; Bhattacharyya, D.; Turton, R.; Zitney, S.

    2012-01-01

    Designing an optimal control system for an integrated gasification combined cycle (IGCC) power plant with CO2 capture addresses the challenge of efficiently operating and controlling a coal-fed IGCC plant with the desired extent of CO2 capture in the face of disturbances without violating operational and environmental constraints. The control system design needs to optimize a desired scalar objective function while satisfying all the operational and environmental constraints in the presence of measured and unmeasured disturbances. Various objective functions can be considered for the control system design such as maximization of profit, maximization of the power produced, or minimization of the auxiliary power. The design of such a control system makes the plant suitable to play an active role in the smart grid era as the plant will have the required agility. In addition, other penalty function(s) such as emission penalties for CO2 or other criteria pollutants can be considered in the framework as well as losses associated with any hydrogen or carbon monoxide loses. The proposed control system design is performed in two stages. In the first stage, a top-down analysis is performed to generate a list of controlled, manipulated, and disturbance variables considering a scalar operational objective and other process constraints. In the second stage, a bottom-up approach for simultaneous design of the control structure and the controllers is used. In this paper, the first stage of the two-stage approach is applied to the IGCC’s acid gas removal (AGR) process which removes both H2S and CO2 from the shifted synthesis gas. While these results are still preliminary, they demonstrate the application of the proposed approach for a commercial-scale plant and show some interesting results related to controlled variable selection. Such an approach can be followed not only to design control systems for new power plants, but also to retrofit control systems for existing plants

  1. Application of Multivariable Statistical Techniques in Plant-wide WWTP Control Strategies Analysis

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Comas, J.; Rodríguez-Roda, I.

    2007-01-01

    The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant...

  2. Optimisation of Control Strategy at the Central Solar Heating Plant in Marstal, Denmark

    DEFF Research Database (Denmark)

    Heller, Alfred

    1999-01-01

    The central solar heating plant at Marstal is monitored since 1996. The data is analysed with focus on the applied constrol strategy for the solar collector field. Variable flow is applied which is not the case at the other plants compared. The project analysed the performance, compared...... the performance with other control strategies and made proposals for furher enhancements....

  3. Modeling the eutrophication of two mature planted stormwater ponds for runoff control

    DEFF Research Database (Denmark)

    Wium-Andersen, Tove; Nielsen, A.H.; Hvitved-Jacobsen, Thorkild

    2013-01-01

    A model, targeting eutrophication of stormwater detention ponds was developed and applied to sim-ulate pH, dissolved oxygen and the development of algae and plant biomass in two mature plantedwetponds for run off control. The model evaluated algal and plant biomass growth into three groupsnamely;...

  4. A study of online plant modelling methods for active control of sound and vibration

    DEFF Research Database (Denmark)

    Laugesen, Søren

    1996-01-01

    Active control systems using the filtered-x algorithm require plant models to describe the relations between the secondary sources and the error sensors. For practical applications online plant modelling may be required if the environment changes significantly. In this study, two dominant methods...

  5. Role of plants and plant based products towards the control of insect pests and vectors:A novel review

    Institute of Scientific and Technical Information of China (English)

    Elumalai Kuppusamy; Saranya Jayakumar

    2016-01-01

    Insect pests bear harmful effects causing great loss to the agricultural crops, stored agricultural products and vector mosquitoes can cause diseases to human. Plants possess an array of vast repository of phytochemicals and have been used to cure many diseases and to control the infestation of insect pests from time immemorial. Plants are easily biodegradable and ecologically safe for treating on the stored or on the field crops against pests to prevent from further damage or loss of stored products or preventing human from mosquito bites, thus preventing the spreading of dreadful diseases such as chikungunya and malaria. Hence, this review can give a clear insecticidal, pesticidal and mosquitocidal property of several plants against the insect pests and vectors.

  6. Dioxin formation and control in a gasification-melting plant.

    Science.gov (United States)

    Kawamoto, Katsuya; Miyata, Haruo

    2015-10-01

    We investigated dioxin formation and removal in a commercial thermal waste treatment plant employing a gasification and melting process that has become widespread in the last decade in Japan. The aim was to clarify the possibility of dioxin formation in a process operation at high temperatures and the applicability of catalytic decomposition of dioxins. Also, the possible use of dioxin surrogate compounds for plant monitoring was further evaluated. The main test parameter was the influence of changes in the amount and type of municipal solid waste (MSW) supplied to the thermal waste treatment plant which from day to day operation is a relevant parameter also from commercial perspective. Here especially, the plastic content on dioxin release was assessed. The following conclusions were reached: (1) disturbance of combustion by adding plastic waste above the capability of the system resulted in a considerable increase in dioxin content of the flue gas at the inlet of the bag house and (2) bag filter equipment incorporating a catalytic filter effectively reduced the gaseous dioxin content below the standard of 0.1 ng toxic equivalency (TEQ)/m(3) N, by decomposition and partly adsorption, as was revealed by total dioxin mass balance and an increased levels in the fly ash. Also, the possible use of organohalogen compounds as dioxin surrogate compounds for plant monitoring was further evaluated. The levels of these surrogates did not exceed values corresponding to 0.1 ng TEQ/m(3) N dioxins established from former tests. This further substantiated that surrogate measurement therefore can well reflect dioxin levels.

  7. A Fuzzy Control System of Turbine Rotate Speed and Power for a Power Plant Simulator

    Institute of Scientific and Technical Information of China (English)

    史小平; 王子才

    2002-01-01

    In this paper, a fuzzy control system of turbine rotate speed and power for a power plant simulator is designed. Rotate speed and power control is a rather important technique in a thermal power plant, because the rotate speed of the turbine rotor and the power of the generator must be enhanced gradually in order to prevent the relative expansion of the cylinder from increasing abruptly. The two parameters of a turbine used to be controlled manually or manual-automatically. To improve the control quality and the automation level, a fuzzy control method is developed for apower plant simulator to fit the DCS (Distributed Control System). The results of practical debugging on the simulator are shown in the paper to demonstrate the correctness and effectiveness of the presented fuzzy control law.

  8. Stability Analysis of DC-link Voltage Control on Autonomous Micro Hydro Power Plant System

    Directory of Open Access Journals (Sweden)

    Feri Yusivar

    2014-12-01

    Full Text Available Micro Hydro Power Plant has become one of the interesting topics to be researched nowadays. This paper deals with the stability analysis on control system of excitation voltage in Micro Hydro Power Plant. The control of this voltage can be achieved by controlling the Permanent Magnet Synchronous Machine (PMSM with particular algorithm so the voltage on the DC-link part of the system can be controlled. Without knowing the exact specification of system parameters, the system will be most likely unstable. The DC-link control system is modeled, simulated, and mathematically analyzed so the parameter specification for the stable system can be obtained.

  9. Application of linear programming techniques for controlling linear dynamic plants in real time

    Science.gov (United States)

    Gabasov, R.; Kirillova, F. M.; Ha, Vo Thi Thanh

    2016-03-01

    The problem of controlling a linear dynamic plant in real time given its nondeterministic model and imperfect measurements of the inputs and outputs is considered. The concepts of current distributions of the initial state and disturbance parameters are introduced. The method for the implementation of disclosable loop using the separation principle is described. The optimal control problem under uncertainty conditions is reduced to the problems of optimal observation, optimal identification, and optimal control of the deterministic system. To extend the domain where a solution to the optimal control problem under uncertainty exists, a two-stage optimal control method is proposed. Results are illustrated using a dynamic plant of the fourth order.

  10. Optimal tuning of a control system for a second-order plant with time delay

    Science.gov (United States)

    Golinko, I. M.

    2014-07-01

    An engineering method for optimizing the parameters of PI and PID controllers for a second-order controlled plant with time delay is considered. An integral quality criterion involving minimization of the control output is proposed for optimizing the control system, which differs from the existing ones in that the effect the control output has on the technological process is taken into account in a correct way. The use of such control makes it possible to minimize the expenditure of material and/or energy resources, to limit the wear, and to increase the service life of the control devices. The unimodal nature of the proposed quality criterion for solving optimal controller tuning problems is numerically confirmed using the optimization theory. A functional correlation between the optimal controller parameters and dynamic properties of a controlled plant is determined for a single-loop control system with the use of calculation methods. The results from simulating the transients in the control system using the proposed and existing functional dependences are compared. The proposed calculation formulas differ from the existing ones by having simple structure, high accuracy of searching for the optimal controller parameters; they allow efficient control to be obtained and can be used for tuning automatic control systems in a wide range of controlled plant dynamic properties. The obtained calculation formulas are recommended for being used by engineers specializing in automation for designing new and optimizing the existing control systems.

  11. 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.

  12. Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control

    OpenAIRE

    2007-01-01

    Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV). ANAV is the consortium that runs the Ascó power plants (2 units) and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC) thermal-hydraulic analysis team has jointly worked togeth...

  13. Coordinated Voltage Control in Offshore HVDC Connected Cluster of Wind Power Plants

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Rather, Zakir Hussain; Rimez, Johan;

    2016-01-01

    This paper presents a coordinated voltage control scheme (CVCS) for a cluster of offshore wind power plants (OWPPs) connected to a VSC HVDC system. The primary control point of the proposed voltage control scheme is the introduced Pilot bus, which is having the highest short circuit capacity...

  14. Dealing with plant variations in multi-model unfalsified switching control via adaptive memory selection

    NARCIS (Netherlands)

    Battistelli, Giorgio; Mosca, Edoardo; Tesi, Pietro

    2011-01-01

    In this paper, a multi-model unfalsified adaptive switching control scheme is proposed for controlling uncertain plants subject to time variations. In the adopted approach, the switching between the candidate controllers is orchestrated according to a hysteresis logic variant wherein the memory leng

  15. Adaptive memory in multi-model switching control of uncertain plants

    NARCIS (Netherlands)

    Battistelli, Giorgio; Mosca, Edoardo; Tesi, Pietro

    2014-01-01

    This paper describes some recent results in multi-model switching control. The scheme here considered embeds a finite family of pre-designed controllers and a high-level unit which selects, at each instant of time, the candidate controller to be placed in feedback to the uncertain plant. The study c

  16. Multi-dimensional Gain Scheduling with Application to Power Plant Control

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Stoustrup, Jakob; Trangbæk, Klaus

    2003-01-01

    This paper deals with gain scheduling control of a power plant model, which is an example of a multi-dimensional nonlinear system. Linear observer-based controllers are designed for a number of linear approximations of the system model in a set of operating points, and gain-scheduling control can...

  17. Compensation Tuning of Analog and Digital Controllers for First Order Plus Time Delay Plants

    Directory of Open Access Journals (Sweden)

    Miluše VÍTEČKOVÁ

    2011-06-01

    Full Text Available The article is devoted to the simple compensation tuning of analog and digital PI and PID controllers for the first order plus time delay plants. The described method makes controller tuning possible so that the control process is non-oscillatory without an overshoot for all input variables. The use is shown in the example.

  18. Design and Analysis of a Slope Voltage Control for a DFIG Wind Power Plant

    DEFF Research Database (Denmark)

    Martínez, J.; Kjær, P. C.; Rodriguez, Pedro

    2012-01-01

    This paper addresses a detailed design of a wind power plant and turbine slope voltage control in the presence of communication delays for a wide short-circuit ratio range operation. The implemented voltage control scheme is based upon the secondary voltage control concept, which offers fast...

  19. Instrumentation, control and automation for biogas plants - a full-scale example

    Energy Technology Data Exchange (ETDEWEB)

    Wiese, J. [EnerCess GmbH, Bad Oeynhausen (Germany)

    2007-07-01

    Biogas plants win more and more importance, because of numerous ecological advantages. That means, the biogas production cycle is an integrated system of resources utilization, organic waste treatment, nutrient recycling and redistribution, and renewable energy production, which creates numerous energetic, environmental and agricultural benefits. In these plants biogas can be produced by using numerous different input substrates: Farm products: cattle and pork liquid manure, wheat, poultry excrements, maize etc.; Organic waste (primarily from food industries): canteen kitchens, food markets, viniculture, brewery, distillery etc.; Sewage sludge from wastewater treatment plants. The processes in biogas plants are similar to processes, which are well known for many decades in anaerobic wastewater/sludge treatment. But up to now, the level of instrumentation, control and automation (ICA) of full-scale biogas systems is still low. I.e. most plants are black box systems which can be analyzed and/or optimized only difficultly. Consequently, the practice shows that many biogas plants are operated suboptimal. Furthermore, for economic reasons more and more plants are operated in a critical (load) range. I.e. there is a high danger of a plant breakdown, which can cause high financial deficits. This situation is mainly caused by the fact, that most of biogas plants are still rather small plants. E.g., the average electricity production capacity of approx. 2,000 biogas plants in Germany is only approx. 125 kWel. But, as a result of technical progress and permanently rising prices for non-renewable energy, biogas plants become more and more economic reasonable. Furthermore, because of the economies of scale law more and more larger plants are built (250 - 2,000 kWel). In case of larger plants, the costs for ICA are only a small part of the total investment costs (5 - 10 %). On larger plants the operators are also usually full-time workers, which can fully concentrate upon the

  20. Fuzzy Adaptive Control System of a Non-Stationary Plant

    Science.gov (United States)

    Nadezhdin, Igor S.; Goryunov, Alexey G.; Manenti, Flavio

    2016-08-01

    This paper proposes a hybrid fuzzy PID control logic, whose tuning parameters are provided in real time. The fuzzy controller tuning is made on the basis of Mamdani controller. In addition, this paper compares a fuzzy logic based PID with PID regulators whose tuning is performed by standard and well-known methods. In some cases the proposed tuning methodology ensures a control performance that is comparable to that guaranteed by simpler and more common tuning methods. However, in case of dynamic changes in the parameters of the controlled system, conventionally tuned PID controllers do not show to be robust enough, thus suggesting that fuzzy logic based PIDs are definitively more reliable and effective.

  1. 40 CFR 63.1583 - What are the emission points and control requirements for an industrial POTW treatment plant?

    Science.gov (United States)

    2010-07-01

    ....1583 What are the emission points and control requirements for an industrial POTW treatment plant? (a) The emission points and control requirements for an existing industrial POTW treatment plant are... control requirements for an industrial POTW treatment plant? 63.1583 Section 63.1583 Protection...

  2. The Development and Research on the Coordinate Control Strategy Between Turbine and Boiler in Fossil Power Plant

    Institute of Scientific and Technical Information of China (English)

    WEI Shuangying

    2006-01-01

    Based on the research on domestic and international automatic technical development in fossil power plant, the paper analyses the recent situation of the coordinate control system between turbine and boiler of domestic fossil Power Plant, provides the development thought of coordinate control system between turbine and boiler, and describes the application prospect in control system of fossil power plant combining with the application experience.

  3. Nonlinear Superheat and Evaporation Temperature Control of a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes novel control of the superheat of the evaporator in a refrigeration system. A new model of the evaporator is developed and based on this model the superheat is transferred to a referred variable. It is shown that control of this variable leads to a linear system independent...... of the working point. The model also gives a method for control of the evaporation temperature. The proposed method is validated by experimental results....

  4. Global-scale environmental control of plant photosynthetic capacity.

    Science.gov (United States)

    Ali, Ashehad A; Xu, Chonggang; Rogers, Alistair; McDowell, Nathan G; Medlyn, Belinda E; Fisher, Rosie A; Wullschleger, Stan D; Reich, Peter B; Vrugt, Jasper A; Bauerle, William L; Santiago, Louis S; Wilson, Cathy J

    2015-12-01

    Photosynthetic capacity, determined by light harvesting and carboxylation reactions, is a key plant trait that determines the rate of photosynthesis; however, in Earth System Models (ESMs) at a reference temperature, it is either a fixed value for a given plant functional type or derived from a linear function of leaf nitrogen content. In this study, we conducted a comprehensive analysis that considered correlations of environmental factors with photosynthetic capacity as determined by maximum carboxylation (V(cm)) rate scaled to 25 degrees C (i.e., V(c),25; μmol CO2 x m(-2)x s(-1)) and maximum electron transport rate (J(max)) scaled to 25 degrees C (i.e., J25; μmol electron x m(-2) x s(-1)) at the global scale. Our results showed that the percentage of variation in observed V(c),25 and J25 explained jointly by the environmental factors (i.e., day length, radiation, temperature, and humidity) were 2-2.5 times and 6-9 times of that explained by area-based leaf nitrogen content, respectively. Environmental factors influenced photosynthetic capacity mainly through photosynthetic nitrogen use efficiency, rather than through leaf nitrogen content. The combination of leaf nitrogen content and environmental factors was able to explain -56% and -66% of the variation in V(c),25 and J25 at the global scale, respectively. Our analyses suggest that model projections of plant photosynthetic capacity and hence land-atmosphere exchange under changing climatic conditions could be substantially improved if environmental factors are incorporated into algorithms used to parameterize photosynthetic capacity in ESMs.

  5. Engineering controlled mammalian type O-Glycosylation in plant cells

    DEFF Research Database (Denmark)

    Yang, Zhang; Drew, Damian Paul; Jørgensen, Bodil

    2011-01-01

    Human mucins are large heavily O-glycosylated glycoproteins (>200 kDa), which account for the majority of proteins in mucus layers that e.g. hydrate, lubricate and protect cells from proteases as well as from pathogens. O-linked mucin glycans are truncated in many cancers, yielding truncated cancer...... specific glyco-peptide epitopes, such as the Tn epitope (GalNAc sugar attached to either Serine or Threonine), which are antigenic to the immune system. In the present study, we have identified plant cells as the only eukaryotic cells without mammalian type O-glycosylation or competing (for sites) O...

  6. Modeling, simulation, and high-autonomy control of a Martian oxygen production plant

    Science.gov (United States)

    Schooley, L. C.; Cellier, F. E.; Wang, F.-Y.; Zeigler, B. P.

    1992-01-01

    Progress on a project for the development of a high-autonomy intelligent command and control architecture for process plants used to produce oxygen from local planetary resources is reported. A distributed command and control architecture is being developed and implemented so that an oxygen production plant, or other equipment, can be reliably commanded and controlled over an extended time period in a high-autonomy mode with high-level task-oriented teleoperation from one or several remote locations. During the reporting period, progress was made at all levels of the architecture. At the remote site, several remote observers can now participate in monitoring the plant. At the local site, a command and control center was introduced for increased flexibility, reliability, and robustness. The local control architecture was enhanced to control multiple tubes in parallel, and was refined for increased robustness. The simulation model was enhanced to full dynamics descriptions.

  7. Development of nuclear power plant online monitoring system using statistical quality control

    Energy Technology Data Exchange (ETDEWEB)

    An, Sang Ha

    2006-02-15

    Statistical Quality Control techniques have been applied to many aspects of industrial engineering. An application to nuclear power plant maintenance and control is also presented that can greatly improve plant safety. As a demonstration of such an approach, a specific system is analyzed: the reactor coolant pumps (RCP) and the fouling resistance of heat exchanger. This research uses Shewart X-bar, R charts, Cumulative Sum charts (CUSUM), and Sequential Probability Ratio Test (SPRT) to analyze the process for the state of statistical control. And we made Control Chart Analyzer (CCA) to support these analyses that can make a decision of error in process. The analysis shows that statistical process control methods can be applied as an early warning system capable of identifying significant equipment problems well in advance of traditional control room alarm indicators. Such a system would provide operators with enough time to respond to possible emergency situations and thus improve plant safety and reliability.

  8. Photosynthesis Control: An underrated short-term regulatory mechanism essential for plant viability.

    Science.gov (United States)

    Colombo, Monica; Suorsa, Marjaana; Rossi, Fabio; Ferrari, Roberto; Tadini, Luca; Barbato, Roberto; Pesaresi, Paolo

    2016-01-01

    Regulation of photosynthetic electron transport provides efficient performance of oxygenic photosynthesis in plants. During the last 15 years, the molecular bases of various photosynthesis short-term regulatory processes have been elucidated, however the wild type-like phenotypes of mutants lacking of State Transitions, Non Photochemical Quenching, or Cyclic Electron Transport, when grown under constant light conditions, have also raised doubts about the acclimatory significance of these short-regulatory mechanisms on plant performance. Interestingly, recent studies performed by growing wild type and mutant plants under field conditions revealed a prominent role of State Transitions and Non Photochemical Quenching on plant fitness, with almost no effect on vegetative plant growth. Conversely, the analysis of plants lacking the regulation of electron transport by the cytochrome b6f complex, also known as Photosynthesis Control, revealed the fundamental role of this regulatory mechanism in the survival of young, developing seedlings under fluctuating light conditions.

  9. Técnica de suturas ajustables: Resultados Technique of adjustable sutures: Results

    Directory of Open Access Journals (Sweden)

    Lourdes R. Hernández Santos

    2001-06-01

    Full Text Available Se realizó un estudio sensorial y motor preoperatorio y posoperatorio a 84 pacientes que acudieron a la consulta de Visión Binocular con el diagnóstico de estrabismo horizontal a partir de los 13 años de edad. El método estadístico utilizado fue "t" o Chi cuadrado. Nos trazamos como objetivo determinar los resultados posoperatorios de la cirugía de estrabismo realizada con la técnica de suturas ajustables, que fueron los siguientes: el 61 % de los pacientes con exotropía y el 71,4 % con el diagnóstico de exotropía se encontraban en ortotropía a los 6 meses de la intervención. El 71,4 % de los pacientes con esotropía y el 83,3 % con el diagnóstico de esotropía se encontraban en ortotropía al año de la intervención. Esta técnica quirúrgica permite la modificación de la desviación en el posoperatorio inmediato.A preoperative and postoperative sensorial and motor study was conducted among 84 patients who received attention at the consultation room of Binocular Vision with the diagnosis of horizontal strabismus from the age of 13 years old on. The statistical method used was "t" or chi square test. Our objective was to determine the postoperative results of the strabismus surgery performed by the technique of adjustable sutures. The results were as follows: 61 % of the patients with exotropia and 71.4 % with the diagnosis of exotropia were in orthotropia 6 months after the operation. 71.4 % of the patients with exotropia and 83.3 % with the diagnosis of exotropia were in orthotropia a year after the operation. This surgical technique allows the modification of the deviation in the immediate postoperative.

  10. Père ou pair? Décalages et ajustements co-énonciatifs

    Directory of Open Access Journals (Sweden)

    Christiane Préneron

    2010-12-01

    Full Text Available

    L’objet de notre analyse dialogique et co-énonciative concerne la forme prise par la relation entre un père et son fi ls au cours d’échanges verbaux. Dans cette dimension relationnelle, nous avons cherché plus particulièrement à éclairer le statut d’énonciateur que chacun octroie à lui-même et à l’autre. Les images qu’un père et un fi ls ont l’un de l’autre et les places qu’ils occupent dans le dialogue sont en partie déterminées par leur statut de père et d’enfant. Ces places ne confi gurent pas un mode relationnel homogène. Au contraire, cet extrait de corpus est frappant par la grande diversité d’attitudes adoptées par le père avec son enfant: tour à tour il lui donne des ordres, des permissions, le réconforte, joue avec lui, lui propose des défi s ou rivalise avec lui. Daniel peut entrer dans le jeu proposé par son père ou s’y opposer, se laisser guider ou refuser, mais aussi être à l’initiative par des demandes ou des jeux. C’est cette diversité que nous tentons de mettre au jour, sachant que certaines séquences se caractérisent plus particulièrement par des décalages entre les interlocuteurs, alors que d’autres conduisent à des ajustements. Si la diversité qui caractérise cet extrait ne saurait être étendue comme caractérisant toute interaction père/enfant, l’analyse qui en est faite peut servir de repère pour l’étude de nouvelles interactions parent/enfant.

  11. Nonlinear superheat and capacity control of a refrigeration plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Larsen, Lars F. S.

    2009-01-01

    This paper proposes a novel method for superheat and capacity control of refrigeration systems. A new low order nonlinear model of the evaporator is developed and used in a backstepping design of a nonlinear controller. The stability of the proposed method is validated theoretically by Lyapunov a...

  12. Nonlinear Superheat and Evaporation Temperature Control of a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes novel control of the superheat of the evaporator in a refrigeration system. A new model of the evaporator is developed and based on this model the superheat is transferred to a referred variable. It is shown that control of this variable leads to a linear system independent...

  13. Nonlinear Superheat Control of a Refrigeration Plant using Backstepping

    DEFF Research Database (Denmark)

    Rasmussen, Henrik

    2008-01-01

    This paper proposes a novel method for superheat and capacity control of refrigeration systems. The main idea is to control the superheat by the compressor speed and capacity by the refrigerant flow. A new low order nonlinear model of the evaporator is developed and used in a backstepping design...

  14. Aquatic Plant Control Research Program. Effects of Water Chemistry on Aquatic Plants. Growth and Photosynthesis of Myriophyllum spicatum L.

    Science.gov (United States)

    1986-05-01

    A D-A±69 98 AQUATIC PLANT CONTROL RESEARCH PRGRAM EFFECTS OF N*TER 1 I CHEMISTRY ON AQUA .(U) ARMY ENGINEER NATERNAYS I EXPERIMENT STATION VICKSBURG...photosynthesis should be clearly resolved. Objective and Scope 6. The objective of this report is to evaluate the effects of major cation and inorganic...carbon levels on the growth and photosynthesis of M. spicaturn. A secondary objective is to evaluate the relationship between growth and

  15. Proposing a new advanced control technique for micro hydro power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hanmandlu, M.; Goyal, Himani [Department of Electrical Engineering, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India)

    2008-05-15

    Micro hydropower plants are emerging as a major renewable energy resource today as they do not encounter the problems of population displacement and environmental problems associated with the large hydro power plants. However, they require control systems to limit the huge variation in input flows expected in rivulets over which these are established to produce a constant power supply. This paper proposes an electric servomotor as a governor for a micro hydro power plant especially those plants that are operated in isolated mode. An advanced controller is developed combining four control schemes for the control of the governor following the concept that the control action can be split up into linear and non-linear parts. The linear part of this controller contains an adaptive fast transversal filter (FTF) algorithm and normalized LMS (nLMS) algorithm. The non-linear part of the controller incorporates Fuzzy PI and a neural network. The concept behind splitting the control action is reasoned out and the conditions for stability of the controller are proved. The new controller has a superior performance compared to other control schemes. (author)

  16. A method of variable spacing for controlled plant growth systems in spaceflight and terrestrial agriculture applications

    Science.gov (United States)

    Knox, J.

    1986-01-01

    A higher plant growth system for Controlled Ecological Life Support System (CELSS) applications is described. The system permits independent movement of individual plants during growth. Enclosed within variable geometry growth chambers, the system allocates only the volume required by the growing plants. This variable spacing system maintains isolation between root and shoot environments, providing individual control for optimal growth. The advantages of the system for hydroponic and aeroponic growth chambers are discussed. Two applications are presented: (1) the growth of soybeans in a space station common module, and (2) in a terrestrial city greenhouse.

  17. Inteligencia emocional y ajuste psicosocial en la adolescencia: El papel de la percepción emocional

    Directory of Open Access Journals (Sweden)

    José M. Salguero

    2011-12-01

    Full Text Available La inteligencia emocional (IE, definida como la habilidad para percibir, usar, comprender y regular las emociones, se ha mostrado como una variable importante a la hora de explicar el ajuste psicosocial de las personas. Pese a ello, la mayor parte de la investigación en torno a la IE ha sido realizada con muestras de población adulta y son escasos los trabajos que, utilizando medidas de ejecución, exploren su papel en la adolescencia. El objetivo del presente estudio fue el de analizar la influencia de la percepción emocional, una de las habilidades recogidas dentro de la IE, sobre el ajuste personal y social de una muestra de adolescentes españoles. Un total de 255 alumnos completaron una tarea de ejecución diseñada para evaluar la percepción emocional en la adolescencia así como diferentes medidas de ajuste social y personal. Los resultados de los análisis de correlación y regresión mostraron cómo los adolescentes con una mayor habilidad para reconocer los estados emocionales de los demás informaron de mejores relaciones sociales con iguales y padres, menor tensión en sus relaciones sociales, así como de un mayor nivel de confianza y competencia percibida. Además, estos resultados se mantuvieron tras controlar los efectos de la edad, el sexo y la personalidad. Se discuten los resultados en el contexto de la investigación sobre la inteligencia emocional y se proponen implicaciones prácticas para el diseño de programas de prevención y tratamiento

  18. Control oriented concentrating solar power (CSP) plant model and its applications

    Science.gov (United States)

    Luo, Qi

    Solar receivers in concentrating solar thermal power plants (CSP) undergo over 10,000 start-ups and shutdowns, and over 25,000 rapid rate of change in temperature on receivers due to cloud transients resulting in performance degradation and material fatigue in their expected lifetime of over 30 years. The research proposes to develop a three-level controller that uses multi-input-multi-output (MIMO) control technology to minimize the effect of these disturbances, improve plant performance, and extend plant life. The controller can be readily installed on any vendor supplied state-of-the-art control hardware. We propose a three-level controller architecture using multi-input-multi-output (MIMO) control for CSP plants that can be implemented on existing plants to improve performance, reliability, and extend the life of the plant. This architecture optimizes the performance on multiple time scalesreactive level (regulation to temperature set points), tactical level (adaptation of temperature set points), and strategic level (trading off fatigue life due to thermal cycling and current production). This controller unique to CSP plants operating at temperatures greater than 550 °C, will make CSPs competitive with conventional power plants and contribute significantly towards the Sunshot goal of 0.06/kWh(e), while responding with agility to both market dynamics and changes in solar irradiance such as due to passing clouds. Moreover, our development of control software with performance guarantees will avoid early stage failures and permit smooth grid integration of the CSP power plants. The proposed controller can be implemented with existing control hardware infrastructure with little or no additional equipment. In the thesis, we demonstrate a dynamics model of CSP, of which different components are modelled with different time scales. We also show a real time control strategy of CSP control oriented model in steady state. Furthermore, we shown different controllers

  19. Comparing a microbial biocide and chlorine as zebra mussel control strategies in an Irish drinking water treatment plant

    National Research Council Canada - National Science Library

    Sara Meehan; Frances E. Lucy; Bridget Gruber; Sarahann Rackl

    2013-01-01

    A need exists for an environmentally friendly mussel control method to replace chlorine and other traditional control methods currentlyutilised in drinking water plants and other infested facilities. Zequanox...

  20. Medicinal plants used to control internal and external parasites in goats

    Directory of Open Access Journals (Sweden)

    Marcia Sanhokwe

    2016-03-01

    Full Text Available The use of medicinal plants plays a major role in the primary health care of animals in South Africa. A survey was conducted to document medicinal plants used to control parasites in goats in Kwezi and Ntambethemba villages in the Eastern Cape Province, South Africa. Information from 50 farmers and 3 herbalists was obtained through the use of a structured questionnaire, and a snowball sampling technique was used to identify key informants. The obtained data were analysed using PROC FREQ of SAS (2003, and fidelity level values were determined to estimate the healing potential of the mentioned plants. The survey revealed nine plant species belonging to eight families that were used to control parasites in goats. Asphodelaceae (22.22% was the most frequently used plant family. Leaves were the most used plant parts, constituting 60.38%. They were prepared either as infusions or decoctions of single plants or in mixtures. Aloe ferox, Acokanthera oppositifolia and Elephantorrhiza elephantina were the plants having the highest fidelity level for their use to control parasites, each scoring 100%, followed by Albuca setosa (83.33%. The study revealed low knowledge about ethnoveterinary medicine in the study area. It also revealed that information on ethno-veterinary medicine in this area is mostly confined to older people and there is danger that this knowledge can be lost before being passed on to other generations. Therefore, there is an urgent need to document information on these plant species so that the future generation can benefit. Further investigation should be carried out to validate the efficacy and safety of the above-mentioned plants so as to provide cheap alternative ways of controlling parasites.Keywords: ailments; ethno-veterinary practices; small ruminant; traditional medicine

  1. Medicinal plants used to control internal and external parasites in goats.

    Science.gov (United States)

    Sanhokwe, Marcia; Mupangwa, Johnfisher; Masika, Patrick J; Maphosa, Viola; Muchenje, Voster

    2016-04-29

    The use of medicinal plants plays a major role in the primary health care of animals in South Africa. A survey was conducted to document medicinal plants used to control parasites in goats in Kwezi and Ntambethemba villages in the Eastern Cape Province, South Africa. Information from 50 farmers and 3 herbalists was obtained through the use of a structured questionnaire, and a snowball sampling technique was used to identify key informants. The obtained data were analysed using PROC FREQ of SAS (2003), and fidelity level values were determined to estimate the healing potential of the mentioned plants. The survey revealed nine plant species belonging to eight families that were used to control parasites in goats. Asphodelaceae (22.22%) was the most frequently used plant family. Leaves were the most used plant parts, constituting 60.38%. They were prepared either as infusions or decoctions of single plants or in mixtures. Aloe ferox, Acokanthera oppositifolia and Elephantorrhiza elephantina were the plants having the highest fidelity level for their use to control parasites, each scoring 100%, followed by Albuca setosa (83.33%). The study revealed low knowledge about ethnoveterinary medicine in the study area. It also revealed that information on ethno-veterinary medicine in this area is mostly confined to older people and there is danger that this knowledge can be lost before being passed on to other generations. Therefore, there is an urgent need to document information on these plant species so that the future generation can benefit. Further investigation should be carried out to validate the efficacy and safety of the above-mentioned plants so as to provide cheap alternative ways of controlling parasites.

  2. Model-based Fuel Flow Control for Fossil-fired Power Plants

    DEFF Research Database (Denmark)

    Niemczyk, Piotr

    2010-01-01

    such sources may vary unpredictably meaning that the desired level of generation cannot always be achieved upon request. On-demand production from controllable units, such as thermal power plants, must change quickly in order to ensure balance between consumer demands and electricity generation. Coal......-fired power plants represent the largest reserve of such controllable power sources in several countries. However, their production take-up rates are limited, mainly due to poor fuel flow control. The thesis presents analysis of difficulties and potential improvements in the control of the coal grinding...

  3. Comparison of two voltage control strategies for a wind power plant

    DEFF Research Database (Denmark)

    Martinez, Jorge; Kjær, Philip C.; Rodriguez, Pedro

    2011-01-01

    , it is possible to investigate the influence of the plant control gain, short circuit ratio, and time delays on the system stability, as well as the fulfillment of the design requirements. The implemented plant voltage control is based on a slope voltage controller, which calculates the references to be sent...... to the wind turbines, according to the slope gain and the difference between the reference and measured voltage at the point of connection. The results show that for a system where the time delay between the central control and the actuators is not negligible, the performance of a decentralized voltage...

  4. Teoría de las Contingencias Múltiples Dinámicamente Entrelazadas (Abriendo la caja negra del ajuste contingente)

    OpenAIRE

    Lic. Jorge Washington Barrientos

    2013-01-01

    La teoría de las contingencias ha ocupado un rol destacado en el estudio del diseño de las estructuras organizacionales en los últimos cincuenta años. Sus contribuciones se han dirigido en distintas direcciones, una de ellas ha sido enumeración de factores de contingencia y la posterior identificación de relaciones entre estos y los elementos estructurales.Refinamientos posteriores han conceptualizado la respuesta sistémica que permite el ajuste (“fit”) de la organización a los cambios en los...

  5. Velocidad de ajuste de la estructura de capital de empresas del sector minero metálico peruano

    OpenAIRE

    Isla López, José Octavio; Flores Orihuela, Alfonso Manuel; Valencia Ramírez, Hernán Octavio

    2015-01-01

    Trabajo de investigación (Magíster en Finanzas) -- Universidad del Pacífico, Escuela de Postgrado, 2015. Asesor: Jorge Eduardo Lladó Márquez. En la presente investigación, se estudia si las empresas del sector minero metálico peruano utilizan óptimamente su endeudamiento o si, por el contrario, incurren en costos que evitan que alcancen su estructura de capital objetivo instantáneamente. Asimismo, se evalúa el impacto de las condiciones macroeconómicas en la velocidad de ajuste hacia su...

  6. RETIRO LABORAL Y AJUSTE A LA JUBILACIÓN DE HOMBRES Y MUJERES EN LA MEDIANA EDAD

    OpenAIRE

    Roxana Cruz Meléndez

    2011-01-01

    En este artículo se presentan los resultados de una investigación aplicada cuyo objeto de estudio fue un grupo de hombres exfuncionarios y mujeres exfuncionarias del área administrativa de la Universidad de Costa Rica (UCR) que se encuentran en la etapa de vida denominada "la mediana edad" y que enfrentan el proceso trabajo-retiro laboral. El estudio consistió en identificar los principales factores que inciden en el retiro laboral a una edad más temprana; la viviencia del proceso, el ajuste ...

  7. Consensos, participación ciudadana y ajuste estructural de las finanzas públicas en Colombia 1998 - 2002

    OpenAIRE

    Carlos Ariel Sanchez-Torres; Rodrigo Naranjo-Galves; Erick Rincón-Cárdenas; Edilberto Peña-González

    2010-01-01

    Este ensayo estudia el proceso de ajuste estructural de las finanzas públicas que ha tenido lugar en Colombia a partir de 1998, con el propósito de examinar desde un punto de vista jurídico-político, en qué medida dicho proceso es resultado de un consenso en la sociedad colombiana y cuáles son las consecuencias de su existencia o de su ausencia, teniendo en cuenta la importancia de la legitimación democrática y el concepto pacto fiscal. Para el efecto, parte de la noción de participación ...

  8. Lucha popular, democracia, neoliberalismo: protesta popular en américa latina en los años del ajuste

    OpenAIRE

    Martha Cecilia García V.

    2010-01-01

    Margarita López Maya (editora). Lucha popular, democracia, neoliberalismo: protesta popular en América Latina en los años del ajuste. Caracas: Nueva Sociedad, 1999, 264 páginas. Este libro presenta una compilación de diez artículos elaborados por investigadores de Argentina, México, Colombia, Guatemala, Brasil, República Dominicana y Venezuela, producto de sus investigaciones sobre luchas y movimientos sociales en estos países. La intención del libro, según la compiladora, es tratar de llegar...

  9. Economic Model Predictive Control for Spray Drying Plants

    DEFF Research Database (Denmark)

    Petersen, Lars Norbert

    and a complexity reduced control model is used for state estimation and prediction in the controllers. These models facilitate development and comparison of control strategies. We develop two MPC strategies; a linear tracking MPC with a Real-Time Optimization layer (MPC with RTO) and an Economic Nonlinear MPC (E...... and sticky powder is avoided from building up on the dryer walls; 3) Demonstrate the industrial application of an MPC strategy to a full-scale industrial four-stage spray dryer. The main scientific contributions can be summarized to: - Modeling of a four-stage spray dryer. We develop new first...

  10. Status and prospects of plant virus control through interference with vector transmission.

    Science.gov (United States)

    Bragard, C; Caciagli, P; Lemaire, O; Lopez-Moya, J J; MacFarlane, S; Peters, D; Susi, P; Torrance, L

    2013-01-01

    Most plant viruses rely on vector organisms for their plant-to-plant spread. Although there are many different natural vectors, few plant virus-vector systems have been well studied. This review describes our current understanding of virus transmission by aphids, thrips, whiteflies, leafhoppers, planthoppers, treehoppers, mites, nematodes, and zoosporic endoparasites. Strategies for control of vectors by host resistance, chemicals, and integrated pest management are reviewed. Many gaps in the knowledge of the transmission mechanisms and a lack of available host resistance to vectors are evident. Advances in genome sequencing and molecular technologies will help to address these problems and will allow innovative control methods through interference with vector transmission. Improved knowledge of factors affecting pest and disease spread in different ecosystems for predictive modeling is also needed. Innovative control measures are urgently required because of the increased risks from vector-borne infections that arise from environmental change.

  11. Coordinated control of wind power plants in offshore HVDC grids

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.

    2017-01-01

    During the recent years, there has been a significant penetration of offshore wind power into the power system and this trend is expected to continue in the future. The North Sea in Europe has higher potential for offshore wind power; therefore, the North Seas Countries' Offshore Grid initiative...... power between different countries, and different synchronous areas. It is very likely that they will then be combined with offshore wind power plant (OWPP) connections in the North Sea, transforming it in a multi terminal DC (MTDC) grid and, therefore, in a fully meshed offshore DC grid in near future...... was formed among nine North Sea countries. They agreed on closer energy cooperation to enable development of an efficient and economic offshore grid infrastructure for advantages, interconnectors based on the voltage source converter based high voltage DC (HVDC) transmission system is being used to exchange...

  12. FT and florigen long-distance flowering control in plants.

    Science.gov (United States)

    Putterill, Joanna; Varkonyi-Gasic, Erika

    2016-10-01

    The great hunt for florigen, the universal, long distance flowering regulator proposed by Chailakhan in the 1930s, resulted in the discovery a decade ago that FT-like proteins fulfilled the predictions for florigen. They are small (∼175 amino acids), globular, phosphatidylethanolamine-binding (PEBP) proteins, phloem-expressed, graft-transmissible and able to move to the shoot apex to act as potent stimulators of flowering in many plants. Genes that regulate Arabidopsis FT protein movement and some features of Arabidopsis FT protein that make it an effective florigen have recently been identified. Although floral promotion via graft transmission of FT has not been demonstrated in trees, FT-like genes have been successfully applied to reducing the long juvenile (pre-flowering) phase of many trees enabling fast track breeding.

  13. Control of Citrus Huanglongbing (HLB) via Trunk Injection of Plant Activators and Antibiotics.

    Science.gov (United States)

    Hu, Jiahuai; Jiang, Junxi; Wang, Nian

    2017-09-15

    Citrus Huanglongbing (HLB) or greening is a devastating disease of citrus worldwide and no effective control measure is currently available. Plant activators represent environment friendly compounds capable of inducing resistance against many plant pathogens. Earlier studies showed that foliar spray of plant defense inducers could slow down HLB disease progress. In this study, eight plant activators and three antibiotics were evaluated in 3 field trials for their effect to control HLB by trunk injection of young and mature sweet orange trees. Results showed that 4 trunk injections of several activators including salicylic acid, oxalic acid, acibenzolar-S-methyl and potassium phosphate provided significant control of HLB by suppressing Las titer and disease progress. Trunk injection of penicillin, streptomycin and oxytetracycline hydrochloride resulted in excellent control of HLB. In general, antibiotics were more effective in reduction of Las titer and HLB symptom expressions than plant activators. These treatments also resulted in increased yield and better fruit quality. Injection of both salicylic acid and acibenzolar-S-methyl led to significant induction of PR-1 and PR-2 genes. Meanwhile, injection of either potassium phosphate or oxalic acid resulted in significant induction of PR-2 or PR-15 gene expression, respectively. These results suggested that HLB diseased trees remained inducible for systemic acquired resistance (SAR) under field conditions. In summary, this study presents information regarding controlling HLB via trunk injection of plant defense activators and antibiotics, which helps citrus growers in decision-making regarding developing an effective HLB management program. .

  14. A novel technology for control of variable speed pumped storage power plant

    Institute of Scientific and Technical Information of China (English)

    Seyed Mohammad Hassan Hosseini; Mohammad Reza Semsar

    2016-01-01

    Variable speed pumped storage machines are used extensively in wind power plant and pumped storage power plant. This paper presents direct torque and flux control (DTFC) of a variable speed pumped storage power plant (VSPSP). By this method both torque and flux have been applied to control the VSPSP. The comparison between VSPSP’s control strategies is studied. At the first, a wind turbine with the capacity 2.2 kW and DTFC control strategies simulated then a 250 MW VSPSP is simulated with all of its parts (including electrical, mechanical, hydraulic and its control system) by MATLAB software. In all of simulations, both converters including two-level voltage source converter (2LVSC) and three-level voltage source converter (3LVSC) are applied. The results of applying 2LVSC and 3LVSC are the rapid dynamic responses with better efficiency, reducing the total harmonic distortion (THD) and ripple of rotor torque and flux.

  15. Parameterised controller synthesis for SISO-LTI uncertain plants using frequency domain information

    Science.gov (United States)

    Parastvand, Hossein; Khosrowjerdi, Mohammad-Javad

    2016-01-01

    This paper extends the results of a new model-free approach which has been applied to guarantee nominal stability and performance. In this paper, using a particular controller structure, the robust stability (RS) and robust performance (RP) criteria for single input single output linear time invariant (SISO-LTI) plants with multiplicative uncertainty are transformed to affine functions in terms of controller parameters. It is shown that solving the feasibility problem of these new criteria will lead to controllers that guarantee the RS and performance. There is no need for a plant mathematical model. The required data for controller synthesis are just the frequency responses corresponding to limited samples of the uncertain plant. Also, there is no need for exact data at each frequency for the whole set of frequency responses. The approach is also applicable for designing both low- and high-order controllers. The effectiveness of the proposed technique is illustrated by simulation results.

  16. OVERVIEW OF A RECONFIGURABLE SIMULATOR FOR MAIN CONTROL ROOM UPGRADES IN NUCLEAR POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring

    2012-10-01

    This paper provides background on a reconfigurable control room simulator for nuclear power plants. The main control rooms in current nuclear power plants feature analog technology that is growing obsolete. The need to upgrade control rooms serves the practical need of maintainability as well as the opportunity to implement newer digital technologies with added functionality. There currently exists no dedicated research simulator for use in human factors design and evaluation activities for nuclear power plant modernization in the U.S. The new research simulator discussed in this paper provides a test bed in which operator performance on new control room concepts can be benchmarked against existing control rooms and in which new technologies can be validated for safety and usability prior to deployment.

  17. Energy-efficient air pollution controls for fossil-fueled plants: Technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sayer, J.H.

    1995-06-01

    The 1990 Clean Air Act Amendments require most fossil-fuel fired power plants to reduce sulfur dioxide, nitrogen oxides, and particulate emissions. While emission-control equipment is available to help most of New York State`s 91 utility units in 31 power plants comply with the new regulations, technologies currently available consume energy, increase carbon dioxide emissions, reduce operating efficiency, and may produce large amounts of solid and/or semisolid byproducts that use additional energy for processing and disposal. This report discribes several pollution-control technologies that are more energy efficient compared to traditional technologies for controlling sulfur dioxide, nitrogen oxide, and particulates, that may have application in New York State. These technologies are either in commercial use, under development, or in the demonstration phase; This report also presents operating characteristics for these technologies and discusses solutions to dispose of pollution-control system byproducts. Estimated energy consumption for emission-control systems relative to a plant`s gross generating capacity is 3 to 5 for reducing up to 90% sulfur dioxide emissions from coal-fired plants. 0.5 to 2.5% for reducing nitrogen oxide emissions by up to 80% from all fossil-fuel fired plants; and 0.5 to 1.5 % for controlling particulate emissions from oil- and coal-fired plants. While fuel switching and/or cofiring with natural gas are options to reduce emissions, these techniques are not considered in this report; the discussion is limited to fossil-fueled steam-generating plants.

  18. Load-following control of an IGCC plant with CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, D.; Turton, R.; Zitney, S.

    2011-01-01

    In this paper, a decentralized control strategy is considered for load-following control of an integrated gasification combined cycle (IGCC) plant with CO2 capture without flaring the syngas. The control strategy considered is gas turbine (GT) lead with gasifier follow. In this strategy, the GT controls the power load by manipulating its firing rate while the slurry feed flow to the gasifier is manipulated to control the syngas pressure at the GT inlet. However, the syngas pressure control is an integrating process with significant timedelay. In this work, a modified proportional-integral-derivative (PID) control is considered for syngas pressure control given that conventional PID controllers show poor control performance for integrating processes with large time delays. The conventional PID control is augmented with an internal feedback loop. The P-controller used in this internal loop converts the integrating process to an open-loop stable process. The resulting secondorder plus time delay model uses a PID controller where the tuning parameters are found by minimizing the integral time-weighted absolute error (ITAE) for disturbance rejection. A plant model with single integrator and time delay is identified by a P-control method. When a ramp change is introduced in the set-point of the load controller, the performance of both the load and pressure controllers with the modified PID control strategy is found to be superior to that using a traditional PID controller. Key

  19. Optimization of Boiler Control for Improvement of Load Following Capabilities of Existing Power Plants

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Pedersen, Tom Søndergaard

    1997-01-01

    An An optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms...... of implementation and commissioning. The optimizing control system takes into account the multivariable and nonlinear characteristics of the boiler process as a gain-scheduled LQG-controller is utilized. Simulation results indicate that a reduction of steam temperature deviations of about 75% can be obtained.......optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms of implementation...

  20. Promise for plant pest control: root-associated pseudomonads with insecticidal activities

    Directory of Open Access Journals (Sweden)

    Peter eKupferschmied

    2013-07-01

    Full Text Available Insects are an important and probably the most challenging pest to control in agriculture, in particular when they feed on belowground parts of plants. The application of synthetic pesticides is problematic owing to side effects on the environment, concerns for public health and the rapid development of resistance. Entomopathogenic bacteria, notably Bacillus thuringiensis and Photorhabdus/ Xenorhabdus species, are promising alternatives to chemical insecticides, for they are able to efficiently kill insects and are considered to be environmentally sound and harmless to mammals. However, they have the handicap of showing limited environmental persistence or of depending on a nematode vector for insect infection. Intriguingly, certain strains of plant root-colonizing Pseudomonas bacteria display insect pathogenicity and thus could be formulated to extend the present range of bioinsecticides for protection of plants against root-feeding insects. These entomopathogenic pseudomonads belong to a group of plant-beneficial rhizobacteria that have the remarkable ability to suppress soil-borne plant pathogens, promote plant growth, and induce systemic plant defenses. Here we review for the first time the current knowledge about the occurrence and the molecular basis of insecticidal activity in pseudomonads with an emphasis on plant-beneficial and prominent pathogenic species. We discuss how this fascinating Pseudomonas trait may be exploited for novel root-based approaches to insect control in an integrated pest management framework.

  1. Promise for plant pest control: root-associated pseudomonads with insecticidal activities.

    Science.gov (United States)

    Kupferschmied, Peter; Maurhofer, Monika; Keel, Christoph

    2013-01-01

    Insects are an important and probably the most challenging pest to control in agriculture, in particular when they feed on belowground parts of plants. The application of synthetic pesticides is problematic owing to side effects on the environment, concerns for public health and the rapid development of resistance. Entomopathogenic bacteria, notably Bacillus thuringiensis and Photorhabdus/Xenorhabdus species, are promising alternatives to chemical insecticides, for they are able to efficiently kill insects and are considered to be environmentally sound and harmless to mammals. However, they have the handicap of showing limited environmental persistence or of depending on a nematode vector for insect infection. Intriguingly, certain strains of plant root-colonizing Pseudomonas bacteria display insect pathogenicity and thus could be formulated to extend the present range of bioinsecticides for protection of plants against root-feeding insects. These entomopathogenic pseudomonads belong to a group of plant-beneficial rhizobacteria that have the remarkable ability to suppress soil-borne plant pathogens, promote plant growth, and induce systemic plant defenses. Here we review for the first time the current knowledge about the occurrence and the molecular basis of insecticidal activity in pseudomonads with an emphasis on plant-beneficial and prominent pathogenic species. We discuss how this fascinating Pseudomonas trait may be exploited for novel root-based approaches to insect control in an integrated pest management framework.

  2. Application of Volatile Antifungal Plant Essential Oils for Controlling Pepper Fruit Anthracnose by Colletotrichum gloeosporioides

    Directory of Open Access Journals (Sweden)

    Jeum Kyu Hong

    2015-09-01

    Full Text Available Anthracnose caused by Colletotrichum gloeosporioides has been destructive during pepper fruit production in outdoor fields in Korea. In vitro antifungal activities of 15 different plant essential oils or its components were evaluated during conidial germination and mycelial growth of C. gloeosporioides. In vitro conidial germination was most drastically inhibited by vapour treatments with carvacrol, cinnamon oil, trans-cinnamaldehyde, citral, p-cymene and linalool. Inhibition of the mycelial growth by indirect vapour treatment with essential oils was also demonstrated compared with untreated control. Carvacrol, cinnamon oil, trans-cinnamaldehyde, citral and eugenol were among the most inhibitory plant essential oils by the indirect antifungal efficacies. Plant protection efficacies of the plant essential oils were demonstrated by reduced lesion diameter on the C. gloeosporioides-inoculated immature green pepper fruits compared to the inoculated control fruits without any plant essential oil treatment. In planta test showed that all plant essential oils tested in this study demonstrated plant protection efficacies against pepper fruit anthracnose with similar levels. Thus, application of different plant essential oils can be used for eco-friendly disease management of anthracnose during pepper fruit production.

  3. Application of Volatile Antifungal Plant Essential Oils for Controlling Pepper Fruit Anthracnose by Colletotrichum gloeosporioides.

    Science.gov (United States)

    Hong, Jeum Kyu; Yang, Hye Ji; Jung, Heesoo; Yoon, Dong June; Sang, Mee Kyung; Jeun, Yong-Chull

    2015-09-01

    Anthracnose caused by Colletotrichum gloeosporioides has been destructive during pepper fruit production in outdoor fields in Korea. In vitro antifungal activities of 15 different plant essential oils or its components were evaluated during conidial germination and mycelial growth of C. gloeosporioides. In vitro conidial germination was most drastically inhibited by vapour treatments with carvacrol, cinnamon oil, trans-cinnamaldehyde, citral, p-cymene and linalool. Inhibition of the mycelial growth by indirect vapour treatment with essential oils was also demonstrated compared with untreated control. Carvacrol, cinnamon oil, trans-cinnamaldehyde, citral and eugenol were among the most inhibitory plant essential oils by the indirect antifungal efficacies. Plant protection efficacies of the plant essential oils were demonstrated by reduced lesion diameter on the C. gloeosporioides-inoculated immature green pepper fruits compared to the inoculated control fruits without any plant essential oil treatment. In planta test showed that all plant essential oils tested in this study demonstrated plant protection efficacies against pepper fruit anthracnose with similar levels. Thus, application of different plant essential oils can be used for eco-friendly disease management of anthracnose during pepper fruit production.

  4. Instrumentation/control systems for food and medicine plants; Shokuhin yakuhin plant no keisoku seigyo system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-10

    The food and medicine industries have been steadily investing facilities for producing new products and improving production efficiency, while coping with the problems associated with superannuated facilities. Fuji Electric has been supplying a new controlling system FOCUS, characterized by its capacity of minimizing cost and openness, since the fall of 1996. It has been adopted by a number of facilities as the monitoring/controlling system, becoming one of the favorite products of the related industries. The FOCUS system developed by the company, which has been supplying a variety of flexible network systems for controlling purposes, easily allows integration of the systems with office LAN`s. This leads to increased proposals for integrated information systems beyond the conventional concept of monitoring/controlling systems, and changed system businesses. (NEDO)

  5. Gain-Scheduled Control of a Fossil-Fired Power Plant Boiler

    DEFF Research Database (Denmark)

    Hangstrup, M.; Stoustrup, Jakob; Andersen, Palle;

    1999-01-01

    In this paper the objective is to optimize the control of a coal fired 250 MW power plant boiler. The conventional control system is supplemented with a multivariable optimizing controller operating in parallel with the conventional control system. Due to the strong dependence of the gains...... and dynamics upon the load, it is beneficial to consider a gain-scheduling control approach. Optimization using complex mu synthesis results in unstable LTI controllers in some operating points of the boiler. A recent gain-scheduling approach allowing for unstable fixed LTI controllers is applied. Gain...

  6. Mitochondrial Quality Control: Decommissioning Power Plants in Neurodegenerative Diseases

    Directory of Open Access Journals (Sweden)

    Rukmini Mukherjee

    2013-01-01

    Full Text Available The cell has an intricate quality control system to protect its mitochondria from oxidative stress. This surveillance system is multi-tiered and comprises molecules that are present inside the mitochondria, in the cytosol, and in other organelles like the nucleus and endoplasmic reticulum. These molecules cross talk with each other and protect the mitochondria from oxidative stress. Oxidative stress is a fundamental part of early disease pathogenesis of neurodegenerative diseases. These disorders also damage the cellular quality control machinery that protects the cell against oxidative stress. This exacerbates the oxidative damage and causes extensive neuronal cell death that is characteristic of neurodegeneration.

  7. An In vitro Study of Bio-Control and Plant Growth Promotion Potential of Salicaceae Endophytes.

    Science.gov (United States)

    Kandel, Shyam L; Firrincieli, Andrea; Joubert, Pierre M; Okubara, Patricia A; Leston, Natalie D; McGeorge, Kendra M; Mugnozza, Giuseppe S; Harfouche, Antoine; Kim, Soo-Hyung; Doty, Sharon L

    2017-01-01

    Microbial communities in the endosphere of Salicaceae plants, poplar (Populus trichocarpa) and willow (Salix sitchensis), have been demonstrated to be important for plant growth promotion, protection from biotic and abiotic stresses, and degradation of toxic compounds. Our study aimed to investigate bio-control activities of Salicaceae endophytes against various soil borne plant pathogens including Rhizoctonia solani AG-8, Fusarium culmorum, Gaeumannomyces graminis var. tritici, and Pythium ultimum. Additionally, different plant growth promoting traits such as biological nitrogen fixation (BNF), indole-3-acetic acid (IAA) biosynthesis, phosphate solubilization, and siderophore production were assessed in all bio-control positive strains. Burkholderia, Rahnella, Pseudomonas, and Curtobacterium were major endophyte genera that showed bio-control activities in the in-vitro assays. The bio-control activities of Burkholderia strains were stronger across all tested plant pathogens as compared to other stains. Genomes of sequenced Burkholderia strains WP40 and WP42 were surveyed to identify the putative genes involved in the bio-control activities. The ocf and hcnABC gene clusters responsible for biosynthesis of the anti-fungal metabolites, occidiofungin and hydrogen cyanide, are present in the genomes of WP40 and WP42. Nearly all endophyte strains showing the bio-control activities produced IAA, solubilized tricalcium phosphate, and synthesized siderophores in the culture medium. Moreover, some strains reduced acetylene into ethylene in the acetylene reduction assay, a common assay used for BNF. Salicaceae endophytes could be useful for bio-control of various plant pathogens, and plant growth promotion possibly through the mechanisms of BNF, IAA production, and nutrient acquisition.

  8. An In vitro Study of Bio-Control and Plant Growth Promotion Potential of Salicaceae Endophytes

    Science.gov (United States)

    Kandel, Shyam L.; Firrincieli, Andrea; Joubert, Pierre M.; Okubara, Patricia A.; Leston, Natalie D.; McGeorge, Kendra M.; Mugnozza, Giuseppe S.; Harfouche, Antoine; Kim, Soo-Hyung; Doty, Sharon L.

    2017-01-01

    Microbial communities in the endosphere of Salicaceae plants, poplar (Populus trichocarpa) and willow (Salix sitchensis), have been demonstrated to be important for plant growth promotion, protection from biotic and abiotic stresses, and degradation of toxic compounds. Our study aimed to investigate bio-control activities of Salicaceae endophytes against various soil borne plant pathogens including Rhizoctonia solani AG-8, Fusarium culmorum, Gaeumannomyces graminis var. tritici, and Pythium ultimum. Additionally, different plant growth promoting traits such as biological nitrogen fixation (BNF), indole-3-acetic acid (IAA) biosynthesis, phosphate solubilization, and siderophore production were assessed in all bio-control positive strains. Burkholderia, Rahnella, Pseudomonas, and Curtobacterium were major endophyte genera that showed bio-control activities in the in-vitro assays. The bio-control activities of Burkholderia strains were stronger across all tested plant pathogens as compared to other stains. Genomes of sequenced Burkholderia strains WP40 and WP42 were surveyed to identify the putative genes involved in the bio-control activities. The ocf and hcnABC gene clusters responsible for biosynthesis of the anti-fungal metabolites, occidiofungin and hydrogen cyanide, are present in the genomes of WP40 and WP42. Nearly all endophyte strains showing the bio-control activities produced IAA, solubilized tricalcium phosphate, and synthesized siderophores in the culture medium. Moreover, some strains reduced acetylene into ethylene in the acetylene reduction assay, a common assay used for BNF. Salicaceae endophytes could be useful for bio-control of various plant pathogens, and plant growth promotion possibly through the mechanisms of BNF, IAA production, and nutrient acquisition.

  9. Inertial Response of Wind Power Plants: A Comparison of Frequency-Based Inertial Control and Stepwise Inertial Control

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiao; Gao, Wenzhong; Wang, Jianhui; Yan, Shijie; Wu, Ziping; Yan, Weihang; Gevorgian, Vahan; Muljadi, Eduard; Kang, Moses; Hwang, Min; Kang, YongCheol

    2016-11-21

    The frequency regulation capability of a wind power plant plays an important role in enhancing frequency reliability especially in an isolated power system with high wind power penetration levels. A comparison of two types of inertial control methods, namely frequency-based inertial control (FBIC) and stepwise inertial control (SIC), is presented in this paper. Comprehensive case studies are carried out to reveal features of the different inertial control methods, simulated in a modified Western System Coordination Council (WSCC) nine-bus power grid using real-time digital simulator (RTDS) platform. The simulation results provide an insight into the inertial control methods under various scenarios.

  10. Modelling and controller design for a UV disinfection plant

    NARCIS (Netherlands)

    van Mourik, S.; Geurts, Bernardus J.; Zwart, Heiko J.; Keesman, Karel

    A mathematical model describing fluid flow and concentration dynamics of micro-organisms inside a UV photoreactor is developed. Using physical arguments and techniques from system theory, we approximate this model by a first order linear one. For this reduced model, we design a controller. The

  11. Modelling and controller design for a UV disinfection plant

    NARCIS (Netherlands)

    van Mourik, S.; Geurts, Bernardus J.; Zwart, Heiko J.

    2007-01-01

    A mathematical model describing fluid flow and concentration dynamics of microorganisms inside a UV photoreactor is developed. Using physical arguments and techniques from system theory, we approximate this model by a first order linear one. For this reduced model, we design a controller. The

  12. Aquatic Plant Control Research Program. White Amur Bibliography.

    Science.gov (United States)

    1983-08-01

    common carp (Cvprinus carpio) genome , yields androgenetic grass carp. Gynogenetic grass carp may be obtained through reLention of the second polar body...of giass carp as a * weed control agent in the United States. Woods, C. 1975. Weed eating fish released in Florida. Citrus and Vegetable Mag. 38(6

  13. Adaptive Superheat Control of a Refrigeration Plant using Backstepping

    DEFF Research Database (Denmark)

    Rasmussen, Henrik

    2008-01-01

    . A new low order nonlinear model of the evaporator is developed and used in a backstepping design of an adaptive nonlinear controller.  The stability of the proposed method is validated theoretically by Lyapunov analysis and experimental results shows the performance of the system for a wide range...

  14. Computer and control applications in a vegetable processing plant

    Science.gov (United States)

    There are many advantages to the use of computers and control in food industry. Software in the food industry takes 2 forms - general purpose commercial computer software and software for specialized applications, such as drying and thermal processing of foods. Many applied simulation models for d...

  15. Aquatic Plants: Management and Control. Special Circular 222.

    Science.gov (United States)

    Wingard, R. G.; And Others

    This publication, produced by the Pennsylvania Cooperative Extension Service, is a non-technical guide to chemical control of aquatic vegetation. The purpose of this circular is to aid the land owner or manager in managing ponds, streams, and other water bodies for desired uses by managing the vegetation in, on, and around the water. Among the…

  16. Modelling and controller design for a UV disinfection plant

    NARCIS (Netherlands)

    Mourik, van S.; Geurts, B.J.; Zwart, H.J.; Keesman, K.J.

    2010-01-01

    A mathematical model describing fluid flow and concentration dynamics of micro-organisms inside a UV photoreactor is developed. Using physical arguments and techniques from system theory, we approximate this model by a first order linear one. For this reduced model, we design a controller. The contr

  17. Automatic Tuning of the Superheat Controller in a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes an automatic tuning of the superheat control in a refrigeration system using a relay method. By means of a simple evaporator model that captures the important dynamics and non-linearities of the superheat a gain-scheduling that compensates for the variation of the process gain...

  18. Companion and refuge plants to control insect pests

    Science.gov (United States)

    Introduction: The sweetpotato whitefly, Bemisia tabaci and aphids are major pests of crops in the southeast USA. An environmentally-friendly management strategy is “push-pull” technology which combines the use of repellent (“push”) and trap crops (“pull”) for insect pest control. The repellent crop,...

  19. Energy saving on wastewater treatment plants through improved online control: case study wastewater treatment plant Antwerp-South.

    Science.gov (United States)

    De Gussem, Kris; Fenu, Alessio; Wambecq, Tom; Weemaes, Marjoleine

    2014-01-01

    This work provides a case study on how activated sludge modelling and computational fluid dynamics (CFD) can help to optimize the energy consumption of a treatment plant that is already equipped with an advanced control based on online nutrient measurements. Currently, aeration basins on wastewater treatment plant Antwerp-South are operated sequentially while flow direction and point of inflow and outflow vary as a function of time. Activated sludge modelling shows that switching from the existing alternating flow based control to a simultaneous parallel feeding of all aeration tanks saves 1.3% energy. CFD calculations also illustrate that the water velocity is still sufficient if some impellers in the aeration basins are shutdown. The simulations of the Activated Sludge Model No. 2d indicate that the coupling of the aeration control with the impeller control, and automatically switching off some impellers when the aeration is inactive, can save 2.2 to 3.3% of energy without affecting the nutrient removal efficiency. On the other hand, all impellers are needed when the aeration is active to distribute the oxygen.

  20. Control of triacylglycerol biosynthesis in plants. Technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    1993-01-31

    Seeds of most species of the Umbelliferae (Apiaciae), Araliaceae, and Garryaceae families are characterized by their high content of the unusual C{sub 18} monounsaturated fatty acid petroselinic acid (18:l{Delta}{sup 6cis}). Prior to a recent report of this lab, little was known of the biosynthetic origin of the cis{Delta}{sup 6} double bond of petroselinic acid. Such knowledge may be of both biochemical and biotechnological significance. Because petroselinic acid is potentially the product of a novel desaturase, information regarding its synthesis may contribute to an understanding of fatty acid desaturation mechanisms in plants. Through chemical cleavage at its double bond, petroselinic acid can be used as a precursor of lauric acid (12:0), a component of detergents and surfactants, and adipic acid (6:0 dicarboxylic), the monomeric component of nylon 6,6. Therefore, the development of an agronomic source of an oil rich in petroselinic acid is of biotechnological interest. As such, studies of petroselinic acid biosynthesis may provide basic information required for any attempt to genetically engineer the production and accumulation of this fatty acid in an existing oilseed.

  1. Electromagnetic techniques for industrial plant process measurements and quality control

    Energy Technology Data Exchange (ETDEWEB)

    Bramanti, M. (Consiglio Nazionale delle Ricerche, Pisa (Italy). Ist. di Elaborazione della Informazione)

    1992-04-01

    In recent years, new real time non-destructive measuring techniques have been developed based on the use of miniaturized components capable of generating, amplifying and elaborating microwave signals (within the range of tenths of a volt and hundreds of milliamps). All these techniques for the measurement of typical process parameters or the non-destructive testing of materials are based on the interaction of radiation with the material or system under examination and make use of the most modern types of data acquisition technology. This article surveys the sensors and measuring instruments which make use of electromagnetic radiation to acquire information concerning the properties of an examined material or system based on their interactions with electromagnetic fields. A few applications are illustrated, e.g., the measurement of unburnt coal in power plant fly ash, the measurement of the quantity of solid particles present in fluidized beds and the verification of the properties of dielectric materials. In each case, the optimum degree of resolution of these devices is made evident.

  2. Natural genetic and induced plant resistance, as a control strategy to plant-parasitic nematodes alternative to pesticides.

    Science.gov (United States)

    Molinari, Sergio

    2011-03-01

    Plant-parasitic nematodes are pests of a wide range of economically important crops, causing severe losses to agriculture. Natural genetic resistance of plants is expected to be a valid solution of the many problems nematodes cause all over the world. Progress in resistance applications is particularly important for the less-developed countries of tropical and subtropical regions, since use of resistant cultivars may be the only possible and economically feasible control strategy in those farming systems. Resistance is being considered of particular importance also in modern high-input production systems of developed countries, as the customary reliance on chemical nematicides has been restricted or has come to an end. This review briefly describes the genetic bases of resistance to nematodes in plants and focuses on the chances and problems of its exploitation as a key element in an integrated management program. Much space is dedicated to the major problem of resistance durability, in that the intensive use of resistant cultivars is likely to increasingly induce the selection of virulent populations able to "break" the resistance. Protocols of pest-host suitability are described, as bioassays are being used to evaluate local nematode populations in their potential to be selected on resistant germplasm and endanger resistant crops. The recent progress in using robust and durable resistances against nematodes as an efficient method for growers in vegetable cropping systems is reported, as well as the possible use of chemicals that do not show any unfavorable impact on environment, to induce in plants resistance against plant-parasitic nematodes.

  3. Historia Funcional de Morfologías Lingüísticas y su Efecto en un Ajuste Convencional

    Directory of Open Access Journals (Sweden)

    Nataly Yáñez Ramírez

    2011-01-01

    Full Text Available Se observó si diferentes historias funcionales construidas durante la adquisición de un conjunto de morfologías lingüísticas facilitaban un ajuste convencional. Participaron 24 estudiantes universitarios distribuidos en tres grupos, expuestos a entrenamientos construidos bajo la lógica de diferentes niveles de interacción: contextual, suplementario o selector (Ribes y López, 1985; y posteriormente se evaluó su ejecución en una tarea convencional. El entrenamiento cuyo criterio de ajuste era de tipo selector fue la que más facilitó tanto la adquisición de las morfologías lingüísticas como su uso en la tarea, efecto que pareció más evidente en los hablantes que en los escuchas. No se encontraron diferencias entre los entrenamientos contextual y suplementario. Los resultados se discuten en términos de sus implicaciones teóricas y metodológicas.

  4. Los adjusted clinicals groups: Un sistema de clasificación de pacientes por ajuste de riesgos

    Directory of Open Access Journals (Sweden)

    Antonio Sicras-Mainar

    2013-06-01

    Full Text Available Los Adjusted Clinical Groups (ACG son un sistema de ajuste de riesgos que clasifica a las personas según su edad y sexo y las condiciones médicas que presentan, y estas personas tienen un consumo similar de recursos sanitarios durante un periodo. Fueron desarrollados por Starfield y Weiner (Universidad Johns Hopkins, EE. UU. 1991, y su objetivo es medir el grado de enfermedad en poblaciones de pacientes basándose en sus niveles de comorbilidad. Entre sus principales aplicaciones destacan: a evaluar la eficiencia en la utilización de los servicios sanitarios, b medir la comorbilidad de la población, y c programar la financiación o pago capitativo para grupos de proveedores. Entre las ventajas del sistema ACG destaca la necesidad de un número limitado de variables para cada paciente (edad, sexo y diagnósticos y que la unidad de medida es el paciente. Se comentan algunas características de este sistema de ajuste de riesgos poblacionales.

  5. Consensos, participación ciudadana y ajuste estructural de las finanzas públicas en Colombia 1998 - 2002

    Directory of Open Access Journals (Sweden)

    Carlos Ariel Sanchez-Torres

    2010-03-01

    Full Text Available Este ensayo estudia el proceso de ajuste estructural de las finanzas públicas que ha tenido lugar en Colombia a partir de 1998, con el propósito de examinar desde un punto de vista jurídico-político, en qué medida dicho proceso es resultado de un consenso en la sociedad colombiana y cuáles son las consecuencias de su existencia o de su ausencia, teniendo en cuenta la importancia de la legitimación democrática y el concepto pacto fiscal. Para el efecto, parte de la noción de participación ciudadana, de la importancia que esta institución tiene en Colombia a partir de 1991, así como de sus limitaciones. Luego se remonta al origen de la situación económica y fiscal que hizo necesario el ajuste y, luego, al acuerdo extendido con el Fondo Monetario Internacional, suscrito en 1999.

  6. Consumo de sustancias durante la adolescencia:trayectorias evolutivas y consecuencias para el ajuste psicológico

    Directory of Open Access Journals (Sweden)

    Alfredo Oliva

    2008-01-01

    Full Text Available Este estudio ha perseguido dos objetivos fundamentales: encontrar diferentes trayectorias en el consumo de sustancias a lo largo de la adolescencia y analizar las consecuencias que este consumo en la adolescencia temprana y media tiene para el ajuste emocional y comportamental al final de la adolescencia. El estudio, con un diseño descriptivo longitudinal mediante cuestionarios, se llevó a cabo sobre una muestra de 101 adolescentes (63 varones y 38 mujeres que fueron estudiados en 3 ocasiones: a los 13, 15 y 18 años de edad. Los resultados mostraron tres grupos de adolescentes en función de las trayectorias seguidas por su consumo de sustancias: consumo bajo, consumo ascendente y experimentación precoz. La comparación entre estos tres grupos indicó un mejor ajuste psicológico en la adolescencia tardía entre los varones y mujeres del grupo de experimentadores, mientras que los problemas de conducta fueron más frecuentes entre los incluidos en el grupo de consumo ascendente. Por otra parte, los análisis de regresión señalaron que el consumo moderado de sustancias en la adolescencia temprana estaba relacionado con una autoestima más alta y con menos problemas emocionales al final de la adolescencia, pero no con más problemas externos.

  7. Control and decision strategies in wastewater treatment plants for operation improvement

    CERN Document Server

    Santín, Ignacio; Vilanova, Ramón

    2017-01-01

    This book examines the operation of biological wastewater treatment plants (WWTPs), with a focus on maintaining effluent water quality while keeping operational costs within constrained limits. It includes control operation and decision schemes and is based on the use of benchmarking scenarios that yield easily reproducible results that readers can implement for their own solutions. The final criterion is the effect of the applied control strategy on plant performance – specifically, improving effluent quality, reducing costs and avoiding violations of established effluent limits. The evaluation of the different control strategies is achieved with the help of two Benchmark Simulation Models (BSM1, BSM2). Given the complexity of the biological and biochemical processes involved and the major fluctuations in the influent flow rate, controlling WWTPs poses a serious challenge. Further, the importance of control goal formulation and control structure design in relation to WWTP process control is widely recogniz...

  8. Model-Free Adaptive Switching Control of Time-Varying Plants

    OpenAIRE

    Battistelli, Giorgio; Hespanha, João P.; Mosca, Edoardo; Tesi, Pietro

    2013-01-01

    This paper addresses the problem of controlling an uncertain time-varying plant by means of a finite family of candidate controllers supervised by an appropriate switching logic. It is assumed that, at every time, the plant consists of an uncertain single-input/single output linear system. It is shown that stability of the switched closed-loop system can be ensured provided that 1) at every time there is at least one candidate controller capable of potentially stabilizing the current time-inv...

  9. DESIGN OF A NEW INTERPOLATED CONTROLLER FOR STABILIZATION OF A SET OF INTERPOLATED PLANTS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Stabilization of a plant with variable operating conditions was considered. The plant is assumed to lie in a set of interpolated models composed of all interpolations generated between certain sets of proper stable coprime factorizations of transfer functions of two representative models that are defined at two representative operating points. An interpolated controller that is linear interpolation of coprime factorizations of two stabilizing controllers for the two representative models is designed to stabilize this set of interpolated models. Design of such an interpolated controller was converted to a feasibility problem constrained by several LMIs and a BMI, and a two-step iteration algorithm was employed to solve it.

  10. Instrumentation and process control for fossil demonstration plants. Quarterly technical progress report, January--March 1977

    Energy Technology Data Exchange (ETDEWEB)

    LeSage, L.G.; O' Fallon, N.M.

    1977-09-01

    Progress during the quarter of January through March 1977 on ANL 189a 49622R2, Instrumentation and Process Control for Fossil Demonstration Plants (FDP) is reported. Work has been performed on updating the study of the state-of-the-art of instrumentation for Fossil Demonstration Plants (FDP), on development of mass-flow and other on-line instruments for FDP, process control analysis for FDP, and organization of a symposium on instrumentation and control for FDP. Progress in these areas is described.

  11. A theoretical study of the modelling and control of a solar water electrolysis plant

    Science.gov (United States)

    Vandergeest, P.; Fahidy, T. Z.

    1980-01-01

    A control-oriented model is presented for a hydrogen producing plant consisting of a conventional water electrolysis process and a photo-assisted water electrolytic installation which utilizes solar energy via a suitable semiconductor/electrolyte assembly. A control strategy for daily hydrogen production is illustrated by a numerical example. The proposed simulation of solar water electrolysis plants is of potential usefulness for automatic control of the photoelectrolytic process when combined with statistical data-logging and model updating carried out in a practical installation.

  12. The status of biological control of plant diseases in soilless cultivation

    NARCIS (Netherlands)

    Postma, J.

    2009-01-01

    Avoidance of plant diseases has been a major driver for the development of soilless cultivation systems. Nevertheless, diseases still occur in these systems and the need for additional control measures exist. Traditionally, control has relied on the use of chemical fungicides but environmental press

  13. Wind Power Plant Control Optimisation with Incorporation of Wind Turbines and STATCOMs

    DEFF Research Database (Denmark)

    Petersen, Lennart; Kryezi, Fitim; Iov, Florin

    2015-01-01

    assessment. An exemplary wind power plant located in the United Kingdom and the corresponding grid code requirements are used as a base case. The final design and tuning process of the voltage controller results in a guidance, proposed for this particular control architecture. It provides qualitative...

  14. The status of biological control of plant diseases in soilless cultivation

    NARCIS (Netherlands)

    Postma, J.

    2009-01-01

    Avoidance of plant diseases has been a major driver for the development of soilless cultivation systems. Nevertheless, diseases still occur in these systems and the need for additional control measures exist. Traditionally, control has relied on the use of chemical fungicides but environmental

  15. Wind Power Plant Control Optimisation with Incorporation of Wind Turbines and STATCOMs

    DEFF Research Database (Denmark)

    Petersen, Lennart; Kryezi, Fitim; Iov, Florin;

    2015-01-01

    assessment. An exemplary wind power plant located in the United Kingdom and the corresponding grid code requirements are used as a base case. The final design and tuning process of the voltage controller results in a guidance, proposed for this particular control architecture. It provides qualitative...

  16. Improved Frequency Control from Wind Power Plants Considering Wind Speed Variation

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Das, Kaushik; Altin, Müfit;

    2016-01-01

    A fast frequency controller (FFC) for wind power plants (WPPs), which produces a temporary overloading power reference based on frequency deviation and rate of change of frequency, is proposed in this paper. Contrary to standard controllers proposed in the literature, the gains of the FFC...

  17. Costs and benefits of biological control of invasive alien plants: case studies from South Africa

    CSIR Research Space (South Africa)

    Van Wilgen, BW

    2004-01-01

    Full Text Available . In many cases, plants are brought under complete control. In this paper, we describe an attempt to estimate the costs and benefits of the biological control of 6 weed species (Opuntia, aurantiaca, Sesbania punicea, Lantana camara, Acacia longifolia, A...

  18. An improved implicit multiple model predictive control used for movable nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Tai Yun, E-mail: nalren@stu.xjtu.edu.c [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an Shaanxi, 710049 (China); Hou Suxia, E-mail: hsxhjj@sina.com.c [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an Shaanxi, 710049 (China); Li Chong, E-mail: abcdirxj@stu.xjtu.edu.c [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an Shaanxi, 710049 (China); Zhao Fuyu, E-mail: fyzhao@mail.xjtu.edu.c [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an Shaanxi, 710049 (China)

    2010-10-15

    Compared with the nuclear power station, the movable nuclear plant has the special requirement of the load following ability and is more difficult to control. In this work, a MMPC (multiple model predictive control) method is applied to the power system of the movable nuclear plant. The linear models used to describe the power changing process, according to which the local controllers are designed, still suffer rough switching. In this paper, work has been done on the improvement of MMPC to make it better in application to the power system of the movable nuclear plant. The simulation results show that these modifications are available to improve the system's dynamic characters, and the multiple strategy is efficacious to solve the control problem of the parameter time-variable nonlinear system.

  19. Design of power control system using SMES and SVC for fusion power plant

    Science.gov (United States)

    Niiyama, K.; Yagai, T.; Tsuda, M.; Hamajima, T.

    2008-02-01

    A SMES (Superconducting Magnetic Energy Storage System) system with converter composed of self-commutated valve devices such as GTO and IGBT is available to control active and reactive power simultaneously. A SVC (Static Var Compensators) or STATCOM (Static Synchronous Compensator) is widely employed to reduce reactive power in power plants and substations. Owing to progress of power electronics technology using GTO and IGBT devices, power converters in the SMES system and the SVC can easily control power flow in few milliseconds. Moreover, since the valve devices for the SMES are equivalent to those for the SVC, the device cost must be reduced. In this paper the basic control system combined with the SMES and SVC is designed for large pulsed loads of a nuclear fusion power plant. This combined system largely expands the reactive power control region as well as the active one. The simulation results show that the combined system is effective and prospective for the nuclear fusion power plant.

  20. Control of distributed heat transfer mechanisms in membrane distillation plants

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-01-05

    Various examples are provided that are related to boundary control in membrane distillation (MD) processes. In one example, a system includes a membrane distillation (MD) process comprising a feed side and a permeate side separated by a membrane boundary layer; and processing circuitry configured to control a water production rate of the MD process based at least in part upon a distributed heat transfer across the membrane boundary layer. In another example, a method includes determining a plurality of estimated temperature states of a membrane boundary layer separating a feed side and a permeate side of a membrane distillation (MD) process; and adjusting inlet flow rate or inlet temperature of at least one of the feed side or the permeate side to maintain a difference temperature along the membrane boundary layer about a defined reference temperature based at least in part upon the plurality of estimated temperature states.

  1. Expert system for controlling plant growth in a contained environment

    Science.gov (United States)

    May, George A. (Inventor); Lanoue, Mark Allen (Inventor); Bethel, Matthew (Inventor); Ryan, Robert E. (Inventor)

    2011-01-01

    In a system for optimizing crop growth, vegetation is cultivated in a contained environment, such as a greenhouse, an underground cavern or other enclosed space. Imaging equipment is positioned within or about the contained environment, to acquire spatially distributed crop growth information, and environmental sensors are provided to acquire data regarding multiple environmental conditions that can affect crop development. Illumination within the contained environment, and the addition of essential nutrients and chemicals are in turn controlled in response to data acquired by the imaging apparatus and environmental sensors, by an "expert system" which is trained to analyze and evaluate crop conditions. The expert system controls the spatial and temporal lighting pattern within the contained area, and the timing and allocation of nutrients and chemicals to achieve optimized crop development. A user can access the "expert system" remotely, to assess activity within the growth chamber, and can override the "expert system".

  2. Control of Plant Diseases by Extracts of Inula viscosa.

    Science.gov (United States)

    Wang, Wenqiao; Ben-Daniel, B H; Cohen, Yigal

    2004-10-01

    ABSTRACT Leaves of Inula viscosa were collected from the field, dried, and extracted with a mixture of acetone and n-hexane. The oily, water-insoluble pastes obtained after evaporation of the solvents were used for the control of foliar diseases in growth chambers. The pastes, either dissolved in acetone or emulsified in water, effectively controlled downy mildew of cucumber, late blight of potato or tomato, powdery mildew of wheat, and rust of sunflower. Mean effective dose (concentration) required for 90% inhibition of disease values for acetone solutions and water emulsions ranged from 0.68 to 1.02% and 0.65 to 1.00% (wt/vol), respectively. Dry matter content in fresh leaves, paste-extract yield in dry leaves, and disease control efficacy of paste extracts were similar in leaves of I. viscosa collected during May to October, suggesting that, for practical use, harvests can be conducted during most of the growing season. The results show that I. viscosa may be used as an herbal source for fungicidal preparations against foliar diseases caused by pathogens belonging to the families Oomycetes, Ascomycetes, and Basidiomycetes.

  3. PID-controller with predictor and auto-tuning algorithm: study of efficiency for thermal plants

    Science.gov (United States)

    Kuzishchin, V. F.; Merzlikina, E. I.; Hoang, Van Va

    2017-09-01

    The problem of efficiency estimation of an automatic control system (ACS) with a Smith predictor and PID-algorithm for thermal plants is considered. In order to use the predictor, it is proposed to include an auto-tuning module (ATC) into the controller; the module calculates parameters for a second-order plant module with a time delay. The study was conducted using programmable logical controllers (PLC), one of which performed control, ATC, and predictor functions. A simulation model was used as a control plant, and there were two variants of the model: one of them was built on the basis of a separate PLC, and the other was a physical model of a thermal plant in the form of an electrical heater. Analysis of the efficiency of the ACS with the predictor was carried out for several variants of the second order plant model with time delay, and the analysis was performed on the basis of the comparison of transient processes in the system when the set point was changed and when a disturbance influenced the control plant. The recommendations are given on correction of the PID-algorithm parameters when the predictor is used by means of using the correcting coefficient k for the PID parameters. It is shown that, when the set point is changed, the use of the predictor is effective taking into account the parameters correction with k = 2. When the disturbances influence the plant, the use of the predictor is doubtful, because the transient process is too long. The reason for this is that, in the neighborhood of the zero frequency, the amplitude-frequency characteristic (AFC) of the system with the predictor has an ascent in comparison with the AFC of the system without the predictor.

  4. Can Coffee Chemical Compounds and Insecticidal Plants Be Harnessed for Control of Major Coffee Pests?

    Science.gov (United States)

    Green, Paul W C; Davis, Aaron P; Cossé, Allard A; Vega, Fernando E

    2015-11-01

    Pests and pathogens threaten coffee production worldwide and are difficult to control using conventional methods, such as insecticides. We review the literature on the chemistry of coffee, concentrating on compounds most commonly reported from Coffea arabica and Coffea canephora. Differences in chemistry can distinguish coffee species and varieties, and plants grown under different biogeographic conditions exhibit different chemotypes. A number of chemical groups, such as alkaloids and caffeoylquinic acids, are known to be insecticidal, but most studies have investigated their effects on coffee quality and flavor. More research is required to bridge this gap in knowledge, so that coffee can be bred to be more resistant to pests. Furthermore, we report on some pesticidal plants that have been used for control of coffee pests. Locally sourced pesticidal plants have been underutilized and offer a sustainable alternative to conventional insecticides and could be used to augment breeding for resilience of coffee plants.

  5. Comparison of Hazard Analysis Requirements for Instrumentation and Control System of Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jang Soo [KAERI, Daejeon (Korea, Republic of); Yoo, Jun Beom [Konkuk University, Seoul (Korea, Republic of)

    2014-08-15

    A hazard, in general, is defined as 'potential for harm.' In this paper, the scope of 'harm' is limited to the loss of a safety function in a Nuclear Power Plant (NPP). The Hazard Analysis (HA) of an Instrumentation and Control (I and C) systems is to identify the relationship from the logical faults, error, and failure of I and C systems to the physical harm of the nuclear power plant, and also to find the impact of the external hazard, e.g., tsunami, of the nuclear power plant to the I and C systems. This paper includes the survey of the existing hazard analysis requirements in the nuclear industries. The purpose of the paper is to compare the HA requirements in various international standards in unclear domain, specifically the safety requirements and guidance for the instrumentation and control system for the nuclear power plant from IAEA, IEC, IEEE, and NRC.

  6. Application of some insecticides and plant crude extracts for controlling insect pests in yard long bean

    Directory of Open Access Journals (Sweden)

    Wipawadee Chamnan

    2003-05-01

    Full Text Available Tests on plant crude extracts of neem seeds, galanga and citronella grass at the rates of 200 ml/20 L of water together with synthetic insecticides, cypermethrin, methamidophos, carbosulfan and carbofuran, at the recommended rates showed that none of the treatments was effective in controlling plant damage caused by adult of bean fly (Ophiomyia phaseoli Tryon. The application of the synthetic insecticide, methamidophos, and plant crude extracts of neem seeds + galanga + citronella grass provided the highest effectiveness tocontrol aphids (Aphis craccivora Koch. Control of A. craccivora was not significantly different between the synthetic insecticide and plant crude extracts, except methamidophos. Pod damage caused by pod borer (Maruca testulalis Geyer and yields were also not significantly different among treatments. However, the highest yield of 1,224.7 kg/rai was recorded in plots treated with neem seed extracts and the synthetic insecticide, carbosulfan. In untreated plots, the lowest yield of 587.3 kg/rai was collected.

  7. Aphid-proof plants: biotechnology-based approaches for aphid control.

    Science.gov (United States)

    Will, Torsten; Vilcinskas, Andreas

    2013-01-01

    Aphids are economically significant agricultural pests that are responsible for large yield losses in many different crops. Because the use of insecticides is restricted in the context of integrated pest management and aphids develop resistance against them rapidly, new biotechnology-based approaches are required for aphid control. These approaches focus on the development of genetically modified aphid-resistant plants that express protease inhibitors, dsRNA, antimicrobial peptides, or repellents, thus addressing different levels of aphid-plant interactions. However, a common goal is to disturb host plant acceptance by aphids and to disrupt their ability to take nutrition from plants. The defense agents negatively affect different fitness-associated parameters such as growth, reproduction, and survival, which therefore reduce the impact of infestations. The results from several different studies suggest that biotechnology-based approaches offer a promising strategy for aphid control.

  8. The effect of transmission route on plant virus epidemic development and disease control.

    Science.gov (United States)

    Jeger, Michael J; Madden, Laurence V; van den Bosch, Frank

    2009-05-21

    A model for indirect vector transmission and epidemic development of plant viruses is extended to consider direct transmission through vector mating. A basic reproduction number is derived which is the sum of the R(0) values specific for three transmission routes. We analyse the model to determine the effect of direct transmission on plant disease control directed against indirect transmission. Increasing the rate of horizontal sexual transmission means that vector control rate or indirect transmission rate must be increased/decreased substantially to maintain R(0) at a value less than 1. By contrast, proportionately increasing the probability of transovarial transmission has little effect. Expressions are derived for the steady-state values of the viruliferous vector population. There is clear advantage for an insect virus in indirect transmission to plants, especially where the sexual and transovarial transmission rates are low; however information on virulence-transmissibility relationships is required to explain the evolution of a plant virus from an insect virus.

  9. Integration of plant defense traits with biological control of arthropod pests: challenges and opportunities

    Directory of Open Access Journals (Sweden)

    Julie A Peterson

    2016-11-01

    Full Text Available Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be semiochemically-, plant toxin-, plant nutrient-, and/or physically-mediated. Case studies involving predators, parasitoids, and pathogens of crop pests will be presented and discussed. These diverse groups of natural enemies may respond differently to crop plant traits based on their own unique biology and the ecological niches they fill. Genetically modified crop plants that have been engineered to express transgenic products affecting herbivorous pests are an additional consideration. For the most part, transgenic plant incorporated protectant (PIP traits are compatible with biological control due to their selective toxicity to targeted pests and relatively low non-target impacts, although transgenic crops may have indirect effects on higher trophic levels and arthropod communities mediated by lower host or prey number and/or quality. Host plant resistance and biological control are two of the key pillars of integrated pest management; their potential interactions, whether they are synergistic, complementary, or disruptive, are key in understanding and achieving sustainable and effective pest management.

  10. Integration of Plant Defense Traits with Biological Control of Arthropod Pests: Challenges and Opportunities.

    Science.gov (United States)

    Peterson, Julie A; Ode, Paul J; Oliveira-Hofman, Camila; Harwood, James D

    2016-01-01

    Crop plants exhibit a wide diversity of defensive traits and strategies to protect themselves from damage by herbivorous pests and disease. These defensive traits may be naturally occurring or artificially selected through crop breeding, including introduction via genetic engineering. While these traits can have obvious and direct impacts on herbivorous pests, many have profound effects on higher trophic levels, including the natural enemies of herbivores. Multi-trophic effects of host plant resistance have the potential to influence, both positively and negatively, biological control. Plant defense traits can influence both the numerical and functional responses of natural enemies; these interactions can be semiochemically, plant toxin-, plant nutrient-, and/or physically mediated. Case studies involving predators, parasitoids, and pathogens of crop pests will be presented and discussed. These diverse groups of natural enemies may respond differently to crop plant traits based on their own unique biology and the ecological niches they fill. Genetically modified crop plants that have been engineered to express transgenic products affecting herbivorous pests are an additional consideration. For the most part, transgenic plant incorporated protectant (PIP) traits are compatible with biological control due to their selective toxicity to targeted pests and relatively low non-target impacts, although transgenic crops may have indirect effects on higher trophic levels and arthropod communities mediated by lower host or prey number and/or quality. Host plant resistance and biological control are two of the key pillars of integrated pest management; their potential interactions, whether they are synergistic, complementary, or disruptive, are key in understanding and achieving sustainable and effective pest management.

  11. Improvement of environmental aspects of thermal power plant operation by advanced control concepts

    Directory of Open Access Journals (Sweden)

    Mikulandrić Robert

    2012-01-01

    Full Text Available The necessity of the reduction of greenhouse gas emissions, as formulated in the Kyoto Protocol, imposes the need for improving environmental aspects of existing thermal power plants operation. Improvements can be reached either by efficiency increment or by implementation of emission reduction measures. Investments in refurbishment of existing plant components or in plant upgrading by flue gas desulphurization, by primary and secondary measures of nitrogen oxides reduction, or by biomass co-firing, are usually accompanied by modernisation of thermal power plant instrumentation and control system including sensors, equipment diagnostics and advanced controls. Impact of advanced control solutions implementation depends on technical characteristics and status of existing instrumentation and control systems as well as on design characteristics and actual conditions of installed plant components. Evaluation of adequacy of implementation of advanced control concepts is especially important in Western Balkan region where thermal power plants portfolio is rather diversified in terms of size, type and commissioning year and where generally poor maintenance and lack of investments in power generation sector resulted in high greenhouse gases emissions and low efficiency of plants in operation. This paper is intended to present possibilities of implementation of advanced control concepts, and particularly those based on artificial intelligence, in selected thermal power plants in order to increase plant efficiency and to lower pollutants emissions and to comply with environmental quality standards prescribed in large combustion plant directive. [Acknowledgements. This paper has been created within WBalkICT - Supporting Common RTD actions in WBCs for developing Low Cost and Low Risk ICT based solutions for TPPs Energy Efficiency increasing, SEE-ERA.NET plus project in cooperation among partners from IPA SA - Romania, University of Zagreb - Croatia and Vinca

  12. Plant diversity effects on ecosystem evapotranspiration and carbon uptake: a controlled environment (Ecotron) and modeling approach

    Science.gov (United States)

    Milcu, Alexandru; Roy, Jacques

    2016-04-01

    Effects of species and functional diversity of plants on ecosystem evapotranspiration and carbon fluxes have been rarely assessed simultaneously. Here we present the results from an experiment that combined a lysimeter setup in a controlled environment facility (Ecotron) with large ecosystem samples/ monoliths originating from a long-term biodiversity experiment ("The Jena Experiment") and a modelling approach. We aimed at (1) quantifying the impact of plant species richness (4 vs. 16 species) on day- and night-time ecosystem water vapor fluxes and carbon uptake, (2) partitioning ecosystem evapotranspiration into evaporation and plant transpiration using the Shuttleworth and Wallace (SW) energy partitioning model, and (3) identifying the most parsimonious predictors of water vapor vapor and CO2 fluxes using plant functional trait-based metrics such as functional diversity and community weighted means. The SW model indicated that at low plant species richness, a higher proportion of the available energy was diverted to evaporation (a non-productive flux), while at higher species richness the proportion of ecosystem transpiration (a production-related water flux) increased. This led to an increased carbon gain per amount of water vapor loss (i.e. increased water use efficiency). While the LAI controlled the carbon and water fluxes, we also found that the diversity of plant functional traits, and in particular of leaf nitrogen concentration are potential important predictors of ecosystem transpiration and carbon uptake and consequently significantly contributed to increase in water use efficiency in communities with higher plant diversity.

  13. Phytocystatins and their potential to control plant diseases caused by fungi.

    Science.gov (United States)

    Lima, Aline M; dos Reis, Savio P; de Souza, Claudia R B

    2015-01-01

    Plant cystatins, also called phytocystatins, constitute a family of specific cysteine protease inhibitors found in several monocots and dicots, where they can be involved in the regulation of several endogenous processes and in defense against pests and pathogens, as well as in response to abiotic stress. In this mini-review we aimed to present isolated and characterized phytocystatins with potential use in control of plant disease caused by fungi.

  14. FRAMEWORK AND APPLICATION FOR MODELING CONTROL ROOM CREW PERFORMANCE AT NUCLEAR POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L Boring; David I Gertman; Tuan Q Tran; Brian F Gore

    2008-09-01

    This paper summarizes an emerging project regarding the utilization of high-fidelity MIDAS simulations for visualizing and modeling control room crew performance at nuclear power plants. The key envisioned uses for MIDAS-based control room simulations are: (i) the estimation of human error associated with advanced control room equipment and configurations, (ii) the investigative determination of contributory cognitive factors for risk significant scenarios involving control room operating crews, and (iii) the certification of reduced staffing levels in advanced control rooms. It is proposed that MIDAS serves as a key component for the effective modeling of cognition, elements of situation awareness, and risk associated with human performance in next generation control rooms.

  15. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle;

    1998-01-01

    therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advantages in terms of implementation and commissioning. The optimizing control system takes account...... of the multivariable and load-de*pendent nonlinear characteristics of the boiler process, as a scheduled LQG controller with feedforward action is utilized. The LQG controller improves the control of critical pro*cess variables, making it possible to increase the load-following capability of a specific plant. Field...

  16. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle;

    therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advantages in terms of implementation and commissioning. The optimizing control system takes account...... of the multivariable and load-de*pendent nonlinear characteristics of the boiler process, as a scheduled LQG controller with feedforward action is utilized. The LQG controller improves the control of critical pro*cess variables, making it possible to increase the load-following capability of a specific plant. Field...

  17. A simulation benchmark to evaluate the performance of advanced control techniques in biological wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Sotomayor O.A.Z.

    2001-01-01

    Full Text Available Wastewater treatment plants (WWTP are complex systems that incorporate a large number of biological, physicochemical and biochemical processes. They are large and nonlinear systems subject to great disturbances in incoming loads. The primary goal of a WWTP is to reduce pollutants and the second goal is disturbance rejection, in order to obtain good effluent quality. Modeling and computer simulations are key tools in the achievement of these two goals. They are essential to describe, predict and control the complicated interactions of the processes. Numerous control techniques (algorithms and control strategies (structures have been suggested to regulate WWTP; however, it is difficult to make a discerning performance evaluation due to the nonuniformity of the simulated plants used. The main objective of this paper is to present a benchmark of an entire biological wastewater treatment plant in order to evaluate, through simulations, different control techniques. This benchmark plays the role of an activated sludge process used for removal of organic matter and nitrogen from domestic effluents. The development of this simulator is based on models widely accepted by the international community and is implemented in Matlab/Simulink (The MathWorks, Inc. platform. The benchmark considers plant layout and the effects of influent characteristics. It also includes a test protocol for analyzing the open and closed-loop responses of the plant. Examples of control applications in the benchmark are implemented employing conventional PI controllers. The following common control strategies are tested: dissolved oxygen (DO concentration-based control, respirometry-based control and nitrate concentration-based control.

  18. Airborne effluent control for LMFBR fuel reprocessing plants

    Energy Technology Data Exchange (ETDEWEB)

    Yarbro, O.O.; Groenier, W.S.; Stephenson, M.J.

    1976-01-01

    A significant part of the LMFBR fuel reprocessing development program has been devoted to the development of efficient removal systems for the volatile fission products, including /sup 131/I, krypton, tritium, /sup 129/I, and most recently /sup 14/C. Flowsheet studies have indicated that very significant reductions of radioactive effluents can be achieved by integrating advanced effluent control systems with new concepts of containment and ventilation; however, the feasibility of such has not yet been established, nor have the economics been examined. This paper presents a flowsheet for the application of advanced containment systems to the processing of LMFBR fuels and summarizes the status and applicability of specific fission product removal systems.

  19. Gene control of flowering time in higher plants

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Flowering involves a transition process from vegetative growth to reproductive development, in which a series of routine changes take place in the shoot apical meristems from metabolic pathway to external phenotype. Expression of the genes related to flowering is the foundation for achieving the transition. Environmental factors (such as vernalization and photoperiod) and the growth status of cell itself induce the expression of the specific genes. A lot of achievements have been made recently in gene control for the determination of flowering time. The article reviews some new advances of such researches related to our work and the interesting field.

  20. Herbivore-induced plant volatiles to enhance biological control in agriculture.

    Science.gov (United States)

    Peñaflor, M F G V; Bento, J M S

    2013-08-01

    Plants under herbivore attack synthetize defensive organic compounds that directly or indirectly affect herbivore performance and mediate other interactions with the community. The so-called herbivore-induced plant volatiles (HIPVs) consist of odors released by attacked plants that serve as important cues for parasitoids and predators to locate their host/prey. The understanding that has been gained on the ecological role and mechanisms of HIPV emission opens up paths for developing novel strategies integrated with biological control programs with the aim of enhancing the efficacy of natural enemies in suppressing pest populations in crops. Tactics using synthetic HIPVs or chemically/genetically manipulating plant defenses have been suggested in order to recruit natural enemies to plantations or help guiding them to their host more quickly, working as a "synergistic" agent of biological control. This review discusses strategies using HIPVs to enhance biological control that have been proposed in the literature and were categorized here as: (a) exogenous application of elicitors on plants, (b) use of plant varieties that emit attractive HIPVs to natural enemies, (c) release of synthetic HIPVs, and (d) genetic manipulation targeting genes that optimize HIPV emission. We discuss the feasibility, benefits, and downsides of each strategy by considering not only field studies but also comprehensive laboratory assays that present an applied approach for HIPVs or show the potential of employing them in the field.

  1. Biotechnological application of functional genomics towards plant-parasitic nematode control.

    Science.gov (United States)

    Li, Jiarui; Todd, Timothy C; Lee, Junghoon; Trick, Harold N

    2011-12-01

    Plant-parasitic nematodes are primary biotic factors limiting the crop production. Current nematode control strategies include nematicides, crop rotation and resistant cultivars, but each has serious limitations. RNA interference (RNAi) represents a major breakthrough in the application of functional genomics for plant-parasitic nematode control. RNAi-induced suppression of numerous genes essential for nematode development, reproduction or parasitism has been demonstrated, highlighting the considerable potential for using this strategy to control damaging pest populations. In an effort to find more suitable and effective gene targets for silencing, researchers are employing functional genomics methodologies, including genome sequencing and transcriptome profiling. Microarrays have been used for studying the interactions between nematodes and plant roots and to measure both plants and nematodes transcripts. Furthermore, laser capture microdissection has been applied for the precise dissection of nematode feeding sites (syncytia) to allow the study of gene expression specifically in syncytia. In the near future, small RNA sequencing techniques will provide more direct information for elucidating small RNA regulatory mechanisms in plants and specific gene silencing using artificial microRNAs should further improve the potential of targeted gene silencing as a strategy for nematode management. © 2011 The Authors. Plant Biotechnology Journal © 2011 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  2. Algorithms for accelerated automatic tuning of controllers with estimating the plant model from the plant response to an impulse disturbance and under self-oscillation conditions

    Science.gov (United States)

    Kuzishchin, V. F.; Tsarev, V. S.

    2014-04-01

    The problem of automatically tuning controllers in an operating control system is considered. Two methods for quickly determining the model parameters with calculating the plant model and the optimal controller tuning parameters in real time are proposed for the preliminary controller tuning stage: from the experimentally obtained plant response to an impulse disturbance and from two periods of self-oscillations excited in the mode of two-position control. The PID controller tunings are determined using the calculation algorithm of indirect frequency optimality indicators. The results from checking the serviceability of the proposed method in a system fitted with an industry-grade controller are presented.

  3. Antifungal activity of plant extracts with potential to control plant pathogens in pineapple

    Directory of Open Access Journals (Sweden)

    Maria Diana Cerqueira Sales

    2016-01-01

    Conclusions: The findings of the present study concluded that mother tinctures can effectively control phytopathogens. The mother tincture extract of Myroxylon balsamum showed antifungal activity and was used here for the first time for inhibition of phytopathogenic fungi. This study paves the way for the development of bioactive natural products with phytosanitary applications, with the added benefits of an environmentally safe and economically viable product.

  4. Evolved Control of Natural Plants: Crossing the Reality Gap for User-Defined Steering of Growth and Motion

    DEFF Research Database (Denmark)

    Hofstadler, Daniel Nicolas; Wahby, Mostafa; Heinrich, Mary Katherine

    2017-01-01

    Mixing societies of natural and artificial systems can provide interesting and potentially fruitful research targets. Here we mix robotic setups and natural plants in order to steer the motion behavior of plants while growing. The robotic setup uses a camera to observe the plant and uses a pair...... of light sources to trigger phototropic response, steering the plant to user-defined targets. An evolutionary robotic approach is used to design a controller for the setup. Initially, preliminary experiments are performed with a simple predetermined controller and a growing bean plant. The plant behavior...... in response to the simple controller is captured by image processing, and a model of the plant tip dynamics is developed. The model is used in simulation to evolve a robot controller that steers the plant tip such that it follows a number of randomly generated target points. Finally, we test the simulation...

  5. Design of Critical Control Systems for Non-Minimum Phase Plants via LTR Technique

    Science.gov (United States)

    Ishihara, Tadashi; Ono, Takahiko

    An application of the loop transfer recovery (LTR) technique to critical control systems design is proposed for non-minimum phase plants. The controller structure is chosen as the Davison type integral controller with the Kalman filter. First, a critical control system is designed on the assumption that the state of the minimum phase part of the plant can be used for the feedback. A quadratic performance index with tuning parameters is used for determining the partial state feedback gain matrix. Second, the Kalman filter gain matrix is determined such that the output feedback controller performs as in the partial state feedback controller. The formal partial loop recovery procedure using the Riccati equation is adopted for this purpose. The proposed design method requires much simpler numerical search than the conventional one-step approach. An illustrative design example is presented.

  6. Ethnoveterinary uses of medicinal plants: a survey of plants used in the ethnoveterinary control of gastro-intestinal parasites of goats in the Eastern Cape Province, South Africa.

    Science.gov (United States)

    Maphosa, Viola; Masika, Patrick Julius

    2010-06-01

    Conventional drugs have become expensive and therefore unaffordable to resource-limited farmers, causing farmers to seek low cost alternatives, such as use of medicinal plants. In this study, a survey was conducted in order to document information on medicinal plants used by farmers in the control of internal parasites in goats in the Eastern Cape Province. Structured questionnaires and general conversation were used to collect the information from farmers and herbalists. The survey revealed 28 plant species from 20 families that are commonly used in the treatment of gastro-intestinal parasites in goats. The plant family Asphodelaceae was frequent in usage, comprising 21.4% of the plants, and the Aloe was the most utilized species (50%). Leaves were the most frequently used plant parts (45.9%), and decoctions constituted the majority of medicinal preparations (70%). Medicinal plants are generally used in combination with other plants, and/or non-plant substances, but a few plants are used on their own. These medicinal plant remedies are administered orally, mainly by use of bottles and this is done twice in summer at intervals of one month, only once in winter and when need arises thereafter. Some of the mentioned plants have been reported in literature to possess anthelmintic properties, while others possess activities ranging from anti-inflammatory, analgesic, antimicrobial, purgative, anti-edema to immuno-regulation. If their safety and efficacy could be confirmed, these plants could form an alternative cost effective strategy in managing helminthiasis in the province.

  7. On the Control of Plants with Hysteresis: Overview and a Prandtl-Ishlinskii Hysteresis Based Control Approach

    Institute of Scientific and Technical Information of China (English)

    Qingqing Wang; Chun-Yi Su; Yonghong Tan

    2005-01-01

    The development of control techniques to mitigate the effects of unknown hysteresis preceding with plants has recently re-attracted significant attention. In this paper, we first give a brief review of presently developed hysteresis models and hysteresis compensating control methods.Then, with the use of the Prandtl-Ishlinskii hysteresis model, we propose a robust adaptive control scheme. The novelty is that the model of hysteresis nonlinearities is firstly fused with the available control techniques without necessarily constructing a hysteresis inverse. The global stability of the adaptive system and tracking a desired trajectory to a certain precision are achieved. Simulations performed on a nonlinear system illustrate and clarify the approach.

  8. Efficacy of plant extracts in controlling wheat leaf rust disease caused by Puccinia triticina

    Directory of Open Access Journals (Sweden)

    Yasser M. Shabana

    2017-03-01

    Full Text Available The efficacy of eight plant extracts (garlic, clove, garden quinine, Brazilian pepper, anthi mandhaari, black cumin, white cedar and neem in controlling leaf rust disease of wheat was investigated in vitro and in vivo. In vitro, all treatments inhibited spore germination by more than 93%. Neem extract recorded 98.99% inhibition of spore germination with no significant difference from the fungicide Sumi-8 (100%. Under greenhouse conditions, seed soaking application in neem extract (at concentration of 2 ml/L resulted in 36.82% reduction in the number of pustules/leaf compared with the untreated control. Foliar spraying of plant extracts on wheat seedlings decreased the number of pustules/leaf. Foliar spraying of plant extracts four days after inoculation led to the highest resistance response of wheat plants against leaf rust pathogen. Spray application of wheat seedlings with neem, clove and garden quinine extracts, four days after inoculation with leaf rust pathogen completely prevented rust development (100% disease control and was comparable with the fungicide Sumi-8. Foliar spray application of wheat plants at mature stage with all plant extracts has significantly reduced the leaf rust infection (average coefficient of infection, ACI compared with the untreated control and neem was the most effective treatment. This was reflected on grain yield components, whereas the 1000-kernel weight and the test weight were improved whether under one- or two-spray applications, with two-spray application being more effective in this regard. Thus, it could be concluded that plant extracts may be useful to control leaf rust disease in Egypt as a safe alternative option to chemical fungicides.

  9. Elementos teóricos del ajuste estacional de series económicas utilizando X-12-ARIMA y TRAMO-SEATS

    OpenAIRE

    Francisco Villarreal

    2005-01-01

    Existen diversos métodos de ajuste estacional, los cuales son utilizados de manera rutinaria tanto en la producción, como en el análisis de series de tiempo económicas en Bancos Centrales, Oficinas de Estadística, así como en diversas agencias públicas y privadas. Si bien la disponibilidad de procedimientos automáticos de ajuste facilitan el procesamiento masivo de series, su uso indiscriminado puede convertir a los diferentes métodos en "cajas negras" para los usuarios. Con el fin de que los...

  10. Elementos teóricos del ajuste estacional de series económicas utilizando X-12-ARIMA y TRAMO-SEATS

    OpenAIRE

    Francisco Villarreal

    2005-01-01

    Existen diversos métodos de ajuste estacional, los cuales son utilizados de manera rutinaria tanto en la producción, como en el análisis de series de tiempo económicas en Bancos Centrales, Oficinas de Estadística, así como en diversas agencias públicas y privadas. Si bien la disponibilidad de procedimientos automáticos de ajuste facilitan el procesamiento masivo de series, su uso indiscriminado puede convertir a los diferentes métodos en "cajas negras" para los usuarios. Con el fin de que los...

  11. Springfield Processing Plant* (A Hypothetical Facility) SPP, Entry Control Point and Vehicle Gate Access Control Post Order

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Gregory A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-06-01

    This hypothetical order provides the requirements and instructions for the Springfield Processing Plant (SPP) Vehicle Gate and Entry Control Point (ECP) in the perimeter access building. The purpose of this post is to prevent the theft, sabotage or diversion of nuclear material (NM), control access and exit at the protected area, and to respond to emergencies according the SPP Guard Force (GF) Contingency Plan and as directed by a Guard Force Supervisor.

  12. Design of a Regenerable Air Revitalization Control System for the ABRS Plant Growth Facility

    Science.gov (United States)

    Monje, Oscar; Monje, Oscar; Shellack, James; Mortenson, Todd; Wells, Howard

    Design of a Regenerable Air Revitalization Control System for the ABRS Plant Growth Facility. O. Monje Space Life Sciences Laboratory, Dynamac Corp., DYN-3, Kennedy Space Center, FL 32899, USA J.L. Shellack, T.E. Mortenson, and H.W. Wells. Bionetics Corporation, BIO-1, Kennedy Space Center, FL 32899, USA The Advanced Biological Research System (ABRS) is a rear-breathing, single middeck locker equivalent plant growth system. ABRS is composed of two independently controlled growth chambers (each with 330 cm2 of growth area). The air revitalization system in each chamber is composed of two subsystems: CO2 Control and a Ethylene/VOC Control. The CO2 Control subsystem must control chamber [CO2] within a range of 300-2000 ppm, with a nominal setpoint of 1500 ppm. The Ethylene/VOC Control subsystem is required to maintain chamber ethylene concentration at ¡50 ppb. Previous spaceflight plant payloads have used non-regenerable cartridges for CO2 control and photocatalytic scrubbers for controlling concentrations of volatile organic compounds (VOCs). Non-regenerable systems have used LiOH cartridges for [CO2] control with a combination of Purafil (KMnO4)/Activated charcoal for scrubbing VOCs. Regenerable air revitalization systems offer the potential for reducing the mass and volume of consumables used during spaceflight plant experiments. A system utilizing technologies employing regenerable adsorbents: zeolites 13X and 5A for CO2 control and Carbosieve SIII (C molecular sieve) for VOC control has been designed for ABRS. The filter cartridges were sized using expected chamber leak rates, measurements of adsorptive capacities, and measured CO2 consumption and VOC generation rates.

  13. Aquatic Plant Control Research Program. Alligatorweed Survey of Ten Southern States

    Science.gov (United States)

    1988-04-01

    alligatorweed in South America for candidate biocon - trol agents, with funding provided largely by the Aquatic Plant Control Research Program (APCRP), CE...Alabama, and Georgia. Control was reported to be unsat- P’ isfactory in Tennessee and the TVA, and no control of alligatorweed by biocon - _ trol insects...to the reduced water levels. None of the biocon - trol agents were collected from any of the sites; however, a native webworm species was found to be

  14. Development and Field Test of the Central Energy Plant Adaptive Control System (CEPACS)

    Science.gov (United States)

    1994-06-01

    conventional P11) mode. PID controllers implemented in pneumatic, electronic, or microcomputer software can be somewhat difficult to set up and may not...plan was repeated using digital PID controllers to create a comparison data set. Appendix A gives details of th" test plan. Test Difficuities Problems...backlash in the drive mechanism. The oscillation was also present when using the Abbott Power Plant continuous pneumatic PID controllers , but at a smaller

  15. Controls over nutrient flow through plants and microbes in Arctic tundra. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schimel, J.

    1994-02-01

    Ecosystem productivity in the Arctic is strongly controlled by N availability to plants. Thus, disturbances to the Arctic system are likely to have their greatest impacts by altering the supply of nutrients to plants. Thus, to understand the dynamics of Arctic tundra, a complete understanding of the controls on N cycling in tundra soils is necessary. This project focused on understanding nutrient dynamics in arctic tussock tundra, specifically evaluating the role of microbial uptake and competition for nutrients as a control on plant N-uptake. The project consisted of several major components: Short- and long-term partitioning of NH{sub 4}{sup +} in tussock tundra (1990--1991); Measurement of NH{sub 4}{sup +} uptake rates by Eriophorum vaginatum and by soil microbes; Determination of microbial NH{sub 4}{sup +} and NO{sub 3}{minus} uptake kinetics; and Determination of the partitioning of NH{sub 4}{sup +} and amino acids between E. vaginatum and soil microbes.

  16. The hormonal control of sex differentiation in dioecious plants of hemp (Cannabis sativd. The influence of plant growth regulators on sex expression in male and female plants

    Directory of Open Access Journals (Sweden)

    Elżbieta Galoch

    2015-05-01

    Full Text Available The influence of GA3, IAA, ethrel, ABA and kinetin on sex expression in male and female plants of hemp (Cannabis sativa cultivar LKC SD was investigated. The growth regulators were applied separately and in combinations on stem apices of plant determined sexually and having the first flower primordia. Gibberellic acid promoted masculinization, whereas IAA, ethylene and kinetin had a feminization effect on sex of hemp. Abscisic acid did not exert any direct effect on sex determination, it however acted antagnisticaly in relation to the effect exerted by GA3 and IAA. The results of combined application of IAA and ethrel with other growth regulators suggest, that the mechanism of action of auxin and ethylene in the control of sex expression in hemp is different. Auxins in this process cannot be regarded only as causing agents of ethylene production increase.

  17. Noncrop flowering plants restore top-down herbivore control in agricultural fields.

    Science.gov (United States)

    Balmer, Oliver; Pfiffner, Lukas; Schied, Johannes; Willareth, Martin; Leimgruber, Andrea; Luka, Henryk; Traugott, Michael

    2013-08-01

    Herbivore populations are regulated by bottom-up control through food availability and quality and by top-down control through natural enemies. Intensive agricultural monocultures provide abundant food to specialized herbivores and at the same time negatively impact natural enemies because monocultures are depauperate in carbohydrate food sources required by many natural enemies. As a consequence, herbivores are released from both types of control. Diversifying intensive cropping systems with flowering plants that provide nutritional resources to natural enemies may enhance top-down control and contribute to natural herbivore regulation. We analyzed how noncrop flowering plants planted as "companion plants" inside cabbage (Brassica oleracea) fields and as margins along the fields affect the plant-herbivore-parasitoid-predator food web. We combined molecular analyses quantifying parasitism of herbivore eggs and larvae with molecular predator gut content analysis and a comprehensive predator community assessment. Planting cornflowers (Centaurea cynanus), which have been shown to attract and selectively benefit Microplitis mediator, a larval parasitoid of the cabbage moth Mamestra brassicae, between the cabbage heads shifted the balance between trophic levels. Companion plants significantly increased parasitism of herbivores by larval parasitoids and predation on herbivore eggs. They furthermore significantly affected predator species richness. These effects were present despite the different treatments being close relative to the parasitoids' mobility. These findings demonstrate that habitat manipulation can restore top-down herbivore control in intensive crops if the right resources are added. This is important because increased natural control reduces the need for pesticide input in intensive agricultural settings, with cascading positive effects on general biodiversity and the environment. Companion plants thus increase biodiversity both directly, by introducing

  18. Control of Cultivable IAA-Producing Bacteria by the Plant Arabidopsis thaliana and the Earthworm Aporrectodea caliginosa

    Directory of Open Access Journals (Sweden)

    Ruben Puga-Freitas

    2012-01-01

    Full Text Available Some soil microorganisms are involved in the complex interactions with plants and earthworms, through the production of indole acetic acid (IAA which modifies plant growth and development. In a factorial experiment testing the impact of the presence/absence of plants and earthworms on IAA production by cultivable bacteria, we observed that plants were decreasing IAA production of 43%, whereas earthworms were increasing it of 46%. In the presence of both plant and earthworms, IAA production was as low as in the presence of plant control, showing that plants influence on IAA production by microorganisms prevails on earthworm influence. We discuss functional reasons which could explain this result.

  19. Progress in Aluminum Electrolysis Control and Future Direction for Smart Aluminum Electrolysis Plant

    Science.gov (United States)

    Zhang, Hongliang; Li, Tianshuang; Li, Jie; Yang, Shuai; Zou, Zhong

    2016-10-01

    The industrial aluminum reduction cell is an electrochemistry reactor that operates under high temperatures and highly corrosive conditions. However, these conditions have restricted the measurement of key control parameters, making the control of aluminum reduction cells a difficult problem in the industry. Because aluminum electrolysis control systems have a significant economic influence, substantial research has been conducted on control algorithms, control systems and information systems for aluminum reduction cells. This article first summarizes the development of control systems and then focuses on the progress made since 2000, including alumina concentration control, temperature control and electrolyte molecular ratio control, fault diagnosis, cell condition prediction and control system expansion. Based on these studies, the concept of a smart aluminum electrolysis plant is proposed. The frame construction, key problems and current progress are introduced. Finally, several future directions are discussed.

  20. O ajuste urbano: as políticas do Banco Mundial e do BID para as cidades

    Directory of Open Access Journals (Sweden)

    Pedro Fiori Arantes

    2006-12-01

    Full Text Available Ao ajuste estrutural que se seguiu à crise da dívida no Terceiro Mundo, no início dos anos 80 - e ainda persiste como um ajuste permanente -, parece ter ocorrido um correspondente" ajuste urbano". Em ambos os casos, o Banco Mundial e, na América Latina, o BID, tiveram ação decisiva, em parceria com as elites e tecnocracias locais. As estratégias de ação dessas duas instituições financeiras, apesar de sua forte interferência nas políticas públicas dos países em desenvolvimento, constituem um tema novo e ainda pouco abordado pela pesquisa acadêmica. Em nosso caso, o objetivo foi desvendar o modelo de cidade que tem sido por elas defendido e qual seu significado. Na dissertação que realizei pela FAUUSP, constatei que os empréstimos do Banco Mundial e do BID - que aparecem aos gestores públicos como" tábuas de salvação" em tempos de crise -, não são" neutros" e carregam consigo uma agenda afirmativa: pretendem modelar um determinado padrão de uso do recurso público e de organização do Estado. As duas instituições difundem políticas públicas que seguem critérios empresariais de rentabilidade e um modelo de gestão estatal terceirizada, à mercê de um corpo técnico privado - formado por gerenciadoras de projeto, fundações privadas, ONGs e inúmeros consultores. Seu objetivo é transformar uma parcela dos governos locais nos países em desenvolvimento, especialmente os que administram os territórios que dão suporte aos negócios transnacionais, em estruturas administrativas treinadas para responder aos grandes interesses privados, ao mesmo tempo em que se desembaraçam de qualquer compromisso com a democracia real.

  1. Sliding Mode Predictive Control of Main Steam Pressure in Coal-fired Power Plant Boiler

    Institute of Scientific and Technical Information of China (English)

    史元浩; 王景成; 章云锋

    2012-01-01

    Since the combustion system of coal-fired boiler in thermal power plant is characterized as time varying, strongly coupled, and nonlinear, it is hard to achieve a satisfactory performance by the conventional proportional integral derivative (PID) control scheme. For the characteristics of the main steam pressure in coal-fired power plant boiler, the sliding mode control system with Smith predictive structure is proposed to look for performance and robustness improvement. First, internal model control (IMC) and Smith predictor (SP) is used to deal with the time delay, and sliding mode controller (SMCr) is designed to overcome the model mismatch. Simulation results show the effectiveness of the proposed controller compared with conventional ones.

  2. Robust control of speed and temperature in a power plant gas turbine.

    Science.gov (United States)

    Najimi, Ebrahim; Ramezani, Mohammad Hossein

    2012-03-01

    In this paper, an H(∞) robust controller has been designed for an identified model of MONTAZER GHAEM power plant gas turbine (GE9001E). In design phase, a linear model (ARX model) which is obtained using real data has been applied. Since the turbine has been used in a combined cycle power plant, its speed and also the exhaust gas temperature should be adjusted simultaneously by controlling fuel signals and compressor inlet guide vane (IGV) position. Considering the limitations on the system inputs, the aim of the control is to maintain the turbine speed and the exhaust gas temperature within desired interval under uncertainties and load demand disturbances. Simulation results of applying the proposed robust controller on the nonlinear model of the system (NARX model), fairly fulfilled the predefined aims. Simulations also show the improvement in the performance compared to MPC and PID controllers for the same conditions.

  3. Discussion on software aging management of nuclear power plant safety digital control system.

    Science.gov (United States)

    Liang, Huihui; Gu, Pengfei; Tang, Jianzhong; Chen, Weihua; Gao, Feng

    2016-01-01

    Managing the aging of digital control systems ensures that nuclear power plant systems are in adequate safety margins during their life cycles. Software is a core component in the execution of control logic and differs between digital and analog control systems. The hardware aging management for the digital control system is similar to that for the analog system, which has matured over decades of study. However, software aging management is still in the exploratory stage. Software aging evaluation is critical given the higher reliability and safety requirements of nuclear power plants. To ensure effective inputs for reliability assessment, this paper provides the required software aging information during the life cycle. Moreover, the software aging management scheme for safety digital control system is proposed on the basis of collected aging information.

  4. Pythium invasion of plant-based life support systems: biological control and sources

    Science.gov (United States)

    Jenkins, D. G.; Cook, K. L.; Garland, J. L.; Board, K. F.; Sager, J. C. (Principal Investigator)

    2000-01-01

    Invasion of plant-based life support systems by plant pathogens could cause plant disease and disruption of life support capability. Root rot caused by the fungus, Pythium, was observed during tests of prototype plant growth systems containing wheat at the Kennedy Space Center (KSC). We conducted experiments to determine if the presence of complex microbial communities in the plant root zone (rhizosphere) resisted invasion by the Pythium species isolated from the wheat root. Rhizosphere inocula of different complexity (as assayed by community-level physiological profile: CLPP) were developed using a dilution/extinction approach, followed by growth in hydroponic rhizosphere. Pythium growth on wheat roots and concomitant decreases in plant growth were inversely related to the complexity of the inocula during 20-day experiments in static hydroponic systems. Pythium was found on the seeds of several different wheat cultivars used in controlled environmental studies, but it is unclear if the seed-borne fungal strain(s) were identical to the pathogenic strain recovered from the KSC studies. Attempts to control pathogens and their effects in hydroponic life support systems should include early inoculation with complex microbial communities, which is consistent with ecological theory.

  5. Control of the Air Supply Subsystem in a PEMFC with Balance of Plant Simulation

    Directory of Open Access Journals (Sweden)

    Alan Cruz Rojas

    2017-01-01

    Full Text Available This paper deals with the design of a control scheme for improving the air supply subsystem of a Proton Exchange Membrane Fuel Cell (PEMFC with maximum power of 65 kW. The control scheme is evaluated in a plant simulator which incorporates the balance of plant (BOP components and is built in the aspenONE® platform. The aspenONE® libraries and tools allows introducing the compressor map and sizing the heat exchangers used to conduct the reactants temperature to the operating value. The PEMFC model and an adaptive controller were programmed to create customized libraries used in the simulator. The structure of the plant control is as follows: the stoichiometric oxygen excess ratio is regulated by manipulating the compressor power, the equilibrium of the anode-cathode pressures is achieved by tracking the anode pressure with hydrogen flow manipulation; the oxygen and hydrogen temperatures are regulated in the heat exchangers, and the gas humidity control is obtained with a simplified model of the humidifier. The control scheme performance is evaluated for load changes, perturbations and parametric variations, introducing a growing current profile covering a large span of power, and a current profile derived from a standard driving speed cycle. The impact of the control scheme is advantageous, since the control objectives are accomplished and the PEMFC tolerates reasonably membrane damage that can produce active surface reduction. The simulation analysis aids to identify the safe Voltage-Current region, where the compressor works with mechanical stability.

  6. Spot drip application of dimethyl disulfide as a post-plant treatment for the control of plant parasitic nematodes and soilborne pathogens in grape production.

    Science.gov (United States)

    Cabrera, J Alfonso; Wang, Dong; Gerik, James S; Gan, Jay

    2014-07-01

    Plant parasitic nematodes and soilborne pathogens can reduce the overall productivity in grape production. Not all grape growers apply soil fumigants before planting, and there is no single rootstock resistant to all nematode species. The aim of this investigation was to evaluate the effect of dimethyl disulfide (DMDS) applied at 112, 224, 448 and 897 kg ha(-1) as a post-plant treatment against soilborne plant parasitic nematodes and pathogens on the grape yield in established grapevines. In microplot and field trials, post-plant fumigation with DMDS controlled citrus (Tylenchulus semipenetrans), root-knot (Meloidogyne spp.), pin (Paratylenchus spp.) and ring (Mesocriconema xenoplax) nematodes in established Thomson Seedless grapevines. However, DMDS did not control the soilborne pathogens Pythium ultimum and Fusarium oxysporum. No indications of phytotoxicity were detected after post-plant fumigation with DMDS. In the field trial, grape yield was significantly higher with the lowest DMDS rate, but no difference among other rates was observed in comparison with the untreated control. Post-plant fumigation with DMDS controlled plant parasitic nematodes in established grapevines but was less efficacious against soilborne pathogens. Low rates of DMDS were sufficient for nematode control and increased the grape yield, probably without affecting beneficial soil organisms. Further research on evaluating the potential effect of DMDS against beneficial soil organisms is needed. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  7. Coordination of baseload power plant group control with static reactive power compensator control

    Directory of Open Access Journals (Sweden)

    Zbigniew Szczerba

    2012-06-01

    Full Text Available Reactive power sources in power system nodes: generators and static reactive power compensators, are controlled by control systems. Generators – by generator node group controllers, compensators – by voltage controllers. The paper presents issues of these control systems’ coordination and proposals for its implementation.

  8. Could plant extracts have enabled hominins to acquire honey before the control of fire?

    Science.gov (United States)

    Kraft, Thomas S; Venkataraman, Vivek V

    2015-08-01

    Honey is increasingly recognized as an important food item in human evolution, but it remains unclear whether extinct hominins could have overcome the formidable collective stinging defenses of honey bees during honey acquisition. The utility of smoke for this purpose is widely recognized, but little research has explored alternative methods of sting deterrence such as the use of plant secondary compounds. To consider whether hominins could have used plant extracts as a precursor or alternative to smoke, we review the ethnographic, ethnobotanical, and plant chemical ecology literature to examine how humans use plants in combination with, and independently of, smoke during honey collection. Plant secondary compounds are diverse in their physiological and behavioral effects on bees and differ fundamentally from those of smoke. Plants containing these chemicals are widespread and prove to be remarkably effective in facilitating honey collection by honey hunters and beekeepers worldwide. While smoke may be superior as a deterrent to bees, plant extracts represent a plausible precursor or alternative to the use of smoke during honey collection by hominins. Smoke is a sufficient but not necessary condition for acquiring honey in amounts exceeding those typically obtained by chimpanzees, suggesting that significant honey consumption could have predated the control of fire. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Controlling hormone signaling is a plant and pathogen challenge for growth and survival.

    Science.gov (United States)

    López, Miguel Angel; Bannenberg, Gerard; Castresana, Carmen

    2008-08-01

    Plants and pathogens have continuously confronted each other during evolution in a battle for growth and survival. New advances in the field have provided fascinating insights into the mechanisms that have co-evolved to gain a competitive advantage in this battle. When plants encounter an invading pathogen, not only responses signaled by defense hormones are activated to restrict pathogen invasion, but also the modulation of additional hormone pathways is required to serve other purposes, which are equally important for plant survival, such as re-allocation of resources, control of cell death, regulation of water stress, and modification of plant architecture. Notably, pathogens can counteract both types of responses as a strategy to enhance virulence. Pathogens regulate production and signaling responses of plant hormones during infection, and also produce phytohormones themselves to modulate plant responses. These results indicate that hormone signaling is a relevant component in plant-pathogen interactions, and that the ability to dictate hormonal directionality is critical to the outcome of an interaction.

  10. 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.

  11. Development of a novel-type transgenic cotton plant for control of cotton bollworm.

    Science.gov (United States)

    Yue, Zhen; Liu, Xiaoguang; Zhou, Zijing; Hou, Guangming; Hua, Jinping; Zhao, Zhangwu

    2016-08-01

    The transgenic Bt cotton plant has been widely planted throughout the world for the control of cotton budworm Helicoverpa armigera (Hubner). However, a shift towards insect tolerance of Bt cotton is now apparent. In this study, the gene encoding neuropeptide F (NPF) was cloned from cotton budworm H. armigera, an important agricultural pest. The npf gene produces two splicing mRNA variants-npf1 and npf2 (with a 120-bp segment inserted into the npf1 sequence). These are predicted to form the mature NPF1 and NPF2 peptides, and they were found to regulate feeding behaviour. Knock down of larval npf with dsNPF in vitro resulted in decreases of food consumption and body weight, and dsNPF also caused a decrease of glycogen and an increase of trehalose. Moreover, we produced transgenic tobacco plants transiently expressing dsNPF and transgenic cotton plants with stably expressed dsNPF. Results showed that H. armigera larvae fed on these transgenic plants or leaves had lower food consumption, body size and body weight compared to controls. These results indicate that NPF is important in the control of feeding of H. armigera and valuable for production of potential transgenic cotton.

  12. Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control

    Directory of Open Access Journals (Sweden)

    F. Reventós

    2008-01-01

    Full Text Available Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV. ANAV is the consortium that runs the Ascó power plants (2 units and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC thermal-hydraulic analysis team has jointly worked together with ANAV engineers at different levels in the analysis and improvement of these reactors. This article is an illustration of the usefulness of computational analysis for operational support. The contents presented were operational between 1985 and 2001 and subsequently changed slightly following various organizational adjustments. The paper has two different parts. In the first part, it describes the specific aspects of thermal-hydraulic analysis tasks related to operation and control and, in the second part, it briefly presents the results of three examples of analyses that were performed. All the presented examples are related to actual situations in which the scenarios were studied by analysts using thermal-hydraulic codes and prepared nodalizations. The paper also includes a qualitative evaluation of the benefits obtained by ANAV through thermal-hydraulic analyses aimed at supporting operation and plant control.

  13. Multi-region fuzzy logic controller with local PID controllers for U-tube steam generator in nuclear power plant

    Directory of Open Access Journals (Sweden)

    Puchalski Bartosz

    2015-12-01

    Full Text Available In the paper, analysis of multi-region fuzzy logic controller with local PID controllers for steam generator of pressurized water reactor (PWR working in wide range of thermal power changes is presented. The U-tube steam generator has a nonlinear dynamics depending on thermal power transferred from coolant of the primary loop of the PWR plant. Control of water level in the steam generator conducted by a traditional PID controller which is designed for nominal power level of the nuclear reactor operates insufficiently well in wide range of operational conditions, especially at the low thermal power level. Thus the steam generator is often controlled manually by operators. Incorrect water level in the steam generator may lead to accidental shutdown of the nuclear reactor and consequently financial losses. In the paper a comparison of proposed multi region fuzzy logic controller and traditional PID controllers designed only for nominal condition is presented. The gains of the local PID controllers have been derived by solving appropriate optimization tasks with the cost function in a form of integrated squared error (ISE criterion. In both cases, a model of steam generator which is readily available in literature was used for control algorithms synthesis purposes. The proposed multi-region fuzzy logic controller and traditional PID controller were subjected to broad-based simulation tests in rapid prototyping software - Matlab/Simulink. These tests proved the advantage of multi-region fuzzy logic controller with local PID controllers over its traditional counterpart.

  14. Adaptive Neural Network Algorithm for Power Control in Nuclear Power Plants

    Science.gov (United States)

    Masri Husam Fayiz, Al

    2017-01-01

    The aim of this paper is to design, test and evaluate a prototype of an adaptive neural network algorithm for the power controlling system of a nuclear power plant. The task of power control in nuclear reactors is one of the fundamental tasks in this field. Therefore, researches are constantly conducted to ameliorate the power reactor control process. Currently, in the Department of Automation in the National Research Nuclear University (NRNU) MEPhI, numerous studies are utilizing various methodologies of artificial intelligence (expert systems, neural networks, fuzzy systems and genetic algorithms) to enhance the performance, safety, efficiency and reliability of nuclear power plants. In particular, a study of an adaptive artificial intelligent power regulator in the control systems of nuclear power reactors is being undertaken to enhance performance and to minimize the output error of the Automatic Power Controller (APC) on the grounds of a multifunctional computer analyzer (simulator) of the Water-Water Energetic Reactor known as Vodo-Vodyanoi Energetichesky Reaktor (VVER) in Russian. In this paper, a block diagram of an adaptive reactor power controller was built on the basis of an intelligent control algorithm. When implementing intelligent neural network principles, it is possible to improve the quality and dynamic of any control system in accordance with the principles of adaptive control. It is common knowledge that an adaptive control system permits adjusting the controller’s parameters according to the transitions in the characteristics of the control object or external disturbances. In this project, it is demonstrated that the propitious options for an automatic power controller in nuclear power plants is a control system constructed on intelligent neural network algorithms.

  15. Ecosystem development in roadside grasslands: Biotic control, plant-soil interactions, and dispersal limitations

    Science.gov (United States)

    Garcia-Palacios, P.; Bowker, M.A.; Maestre, F.T.; Soliveres, S.; Valladares, F.; Papadopoulos, J.; Escudero, A.

    2011-01-01

    Roadside grasslands undergoing secondary succession are abundant, and represent ecologically meaningful examples of novel, human-created ecosystems. Interactions between plant and soil communities (hereafter plant-soil interactions) are of major importance in understanding the role of biotic control in ecosystem functioning, but little is known about these links in the context of ecosystem restoration and succession. The assessment of the key biotic communities and interactions driving ecosystem development will help practitioners to better allocate the limited resources devoted to roadside grassland restoration. We surveyed roadside grasslands from three successional stages (0-2, 7-9, and > 20 years) in two Mediterranean regions of Spain. Structural equation modeling was used to evaluate how interactions between plants, biological soil crusts (BSCs), and soil microbial functional diversity (soil microorganisms) affect indicators of ecosystem development and restoration: plant similarity to the reference ecosystem, erosion control, and soil C storage and N accumulation. Changes in plant community composition along the successional gradient exerted the strongest influence on these indicators. High BSC cover was associated with high soil stability, and high soil microbial functional diversity from late-successional stages was associated with high soil fertility. Contrary to our expectations, the indirect effects of plants, mediated by either BSCs or soil microorganisms, were very weak in both regions, suggesting a minor role for plant-soil interactions upon ecosystem development indicators over long periods. Our results suggest that natural vegetation dynamics effectively improved ecosystem development within a time frame of 20 years in the grasslands evaluated. They also indicate that this time could be shortened if management actions focus on: (1) maintaining wellconserved natural areas close to roadsides to enhance plant compositional changes towards late

  16. Construction of biological control strain of Trichoderma viride and study of their ability to induce plant disease resistance

    Institute of Scientific and Technical Information of China (English)

    LIU Shi-wang; GUO Ze-jian

    2004-01-01

    @@ Plant diseases heavily affct plant growth and crop yield even in modern agriculture. Control its difficult because pathogens mutate frequently, and this leads in frequent breaking of disease resistance in commercial cultivars. The excessive application of chemical pesticides is not only producing pesticideresistant pathogens, but it is harming the environment threatening the health of human beings.Therefore, the use of biological control agents (BCA) may provide an environmental friendly alternative to chemicals for plant disease control. Hypersensitive response (HR) and systemic acquired resistance (SAR) are the typical expressions of plant defense reactions. Once SAR is established,, the plants exhibits a broad-spectrum of disease resistance against pathogen attack. Researchers have identified elicitor proteins, such as elicitins and harpins, which activate plant defense reactions. It would be useful to explore the possibility of using biological control agents to induce a status of SAR in crop plants.

  17. ENERGY EFFICIENT FLOW AND LEVEL CONTROL IN A HYDRO POWER PLANT USING FUZZY LOGIC

    Directory of Open Access Journals (Sweden)

    A. Selwin Mich Priyadharson

    2014-01-01

    Full Text Available The main objective and an innovative design of this work is to improve the energy efficiency by controlling the variables flow and level in a hydroelectric power plant using Programmable Logic Control (PLC-Human Machine Interface (HMI and fuzzy logic approach. This project will focus on design and development of flow and level controller for small scale hydro generating units by implementing gate control based on PLC-HMI and Fuzzy Logic Control (FLC. So far there is no other better performing control scheme, with uncomplicated approach, in order to match and satisfy the dynamic changes in load demand. In this project, FLC will be applied to flow and level control for small scale hydro generating units is proposed. A lab scale experimental setup is made-up as prototype model for flow and level control and simulation outputs were achieved, using PLC-HMI based fuzzy controller scheme. The hardware set up is designed with 5 stages in the tank 1 and 2 stages in the tank 2. Based on the outputs of the level sensors from tanks 1 and 2, the ladder logic will perform. B&R Industrial Automation PLC inbuilt with 24 digital inputs and provides 16 potential free outputs is used to perform control action. Finally, the performance of the proposed scheme is evaluated by simulation results by comparing with conventional controllers output using the data collected from the hydroelectric power plant. The merits of the proposed Fuzzy scheme over the conventional method are spotlighted.

  18. Malfunction analysis response system (MARS) for nuclear power plants control rooms

    Energy Technology Data Exchange (ETDEWEB)

    Peters, F.; Rossmann, D.L.

    1984-01-01

    Whenever the need for the safe and reliable operation of a complex system exists, a major requirement for success is the actions of the people involved. This is especially true when a time-critical response is required. In this context, the operation of a nuclear power plant is exemplary. Lessons from the Three Mile Island-2 incident show that insufficient attention was paid to the man/machine interface. Since that time, considerable effort has been directed by the nuclear industry toward the improvement of control room instrumentation, emergency operating procedures, and operator training. The improvement of the safety of nuclear power plants through the reduction of operator errors is discussed. The nuclear power plant operator's diagnostic role is analogous to that of a flight controller for a manned space flight mission. Both must be able to quickly understand and integrate large quantities of information on current system operation with background data on system design and performance.

  19. Designing the controllability of a HVAC-plant by dynamic simulation

    Energy Technology Data Exchange (ETDEWEB)

    Novakovic, V.; Grindal, A.

    1994-05-01

    This paper was presented at CLIMA 2000 - The international conference on energy and environmental matters in built environment, London, 1.-3. November 1993. Nowadays, HVAC engineers can use dynamic simulation programs in their everyday work. Such tools provide the ability to analyze different system configurations and to check the obtained states even before the building and plant are constructed. To encourage its wider use, the authors present in this paper the experiences obtained with the simulation program HVAC-DYNAMICS. The program was used to simulate the retrofitting of a heat recovery wheel to a conventional ventilation plant with a hot water heating coil. The effects of different design parameters on the controllability of the plant were investigated. Interestingly, some commonly recommended ``clever`` configurations can lead to unexpected control scenarios. 4 refs., 3 figs., 2 tabs.

  20. A suitable model plant for control of the set fuel cell-DC/DC converter

    Energy Technology Data Exchange (ETDEWEB)

    Andujar, J.M.; Segura, F.; Vasallo, M.J. [Departamento de Ingenieria Electronica, Sistemas Informaticos y Automatica, E.P.S. La Rabida, Universidad de Huelva, Ctra. Huelva - Palos de la Frontera, S/N, 21819 La Rabida - Palos de la Frontera Huelva (Spain)

    2008-04-15

    In this work a state and transfer function model of the set made up of a proton exchange membrane (PEM) fuel cell and a DC/DC converter is developed. The set is modelled as a plant controlled by the converter duty cycle. In addition to allow setting the plant operating point at any point of its characteristic curve (two interesting points are maximum efficiency and maximum power points), this approach also allows the connection of the fuel cell to other energy generation and storage devices, given that, as they all usually share a single DC bus, a thorough control of the interconnected devices is required. First, the state and transfer function models of the fuel cell and the converter are obtained. Then, both models are related in order to achieve the fuel cell+DC/DC converter set (plant) model. The results of the theoretical developments are validated by simulation on a real fuel cell model. (author)

  1. Sharka epidemiology and worldwide management strategies: learning lessons to optimize disease control in perennial plants.

    Science.gov (United States)

    Rimbaud, Loup; Dallot, Sylvie; Gottwald, Tim; Decroocq, Véronique; Jacquot, Emmanuel; Soubeyrand, Samuel; Thébaud, Gaël

    2015-01-01

    Many plant epidemics that cause major economic losses cannot be controlled with pesticides. Among them, sharka epidemics severely affect prunus trees worldwide. Its causal agent, Plum pox virus (PPV; genus Potyvirus), has been classified as a quarantine pathogen in numerous countries. As a result, various management strategies have been implemented in different regions of the world, depending on the epidemiological context and on the objective (i.e., eradication, suppression, containment, or resilience). These strategies have exploited virus-free planting material, varietal improvement, surveillance and removal of trees in orchards, and statistical models. Variations on these management options lead to contrasted outcomes, from successful eradication to widespread presence of PPV in orchards. Here, we present management strategies in the light of sharka epidemiology to gain insights from this worldwide experience. Although focused on sharka, this review highlights more general levers and promising approaches to optimize disease control in perennial plants.

  2. Plant i - AAA protease controls the turnover of the essential mitochondrial protein import component.

    Science.gov (United States)

    Opalińska, Magdalena; Parys, Katarzyna; Murcha, Monika W; Jańska, Hanna

    2017-03-06

    Mitochondria are multifunctional organelles that play a central role in energy metabolism. Due to life-essential functions of these organelles, mitochondrial content, quality, and dynamics are tightly controlled. Across the species, highly conserved ATP - dependent proteases prevent malfunction of mitochondria through versatile activities. This study focuses on a molecular function of plant mitochondrial inner membrane-embedded i - AAA protease, FTSH4, providing its first bona fide substrate. Here, we report that the abundance of Tim17-2 protein, the essential component of the TIM17:23 translocase, is directly controlled by the proteolytic activity of FTSH4. Plants that are lacking functional FTSH4 protease are characterized by significantly enhanced capacity of preprotein import through the TIM17:23 - dependent pathway. Together with the observation that FTSH4 prevents accumulation of Tim17-2, our data points towards the role of this i - AAA protease in the regulation of mitochondrial biogenesis in plants.

  3. RETIRO LABORAL Y AJUSTE A LA JUBILACIÓN DE HOMBRES Y MUJERES EN LA MEDIANA EDAD

    Directory of Open Access Journals (Sweden)

    Roxana Cruz Meléndez

    2011-01-01

    Full Text Available En este artículo se presentan los resultados de una investigación aplicada cuyo objeto de estudio fue un grupo de hombres exfuncionarios y mujeres exfuncionarias del área administrativa de la Universidad de Costa Rica (UCR que se encuentran en la etapa de vida denominada "la mediana edad" y que enfrentan el proceso trabajo-retiro laboral. El estudio consistió en identificar los principales factores que inciden en el retiro laboral a una edad más temprana; la viviencia del proceso, el ajuste a la jubilación y sus implicaciones a nivel personal y social. La información recopilada se obtuvo a partir de la técnica "la entrevista fenomenológica" concebida como una exploración profunda que proporciona datos de gran valor conceptual y humana; en ella, tanto la persona que entrevista como la entrevistada mantienen un compromiso para que la búsqueda de la información sea dentro de una relación empática. Partiendo de lo subjetivo por su historia de vida al mandato social por lo roles asignados y asumidos por la población en estudio. Los resultados obtenidos indican que pareciera que la valoración que cada uno de los participantes hace de su rol laboral y el significado del trabajo en sus vidas es determinante en el proceso de retiro laboral y su ajuste al rol de persona jubilada.

  4. Controlling fungal foliar pathogen e.g. Venturia inaequalis, Blumeriella jaapi, in plants involves treating plants with a composition comprising an extract from Yucca as an antifungal agent

    DEFF Research Database (Denmark)

    2007-01-01

    The invention relates to control of fungal foliar diseases in plants, preferaby Rosaceae, such as apple scab (Venturia inaequalis), pear scab (Venturia pirina), brown spot (Stemphylium vesicarium) and powdery mildew (Podosphaera leucotricha) by treatment of plant with an extract of Yucca species...

  5. Coordinated Control Scheme for Ancillary Services from Offshore Wind Power Plants to AC and DC Grids

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Altin, Müfit; Hansen, Anca Daniela;

    2016-01-01

    This paper proposes a new approach of providing ancillary services to AC and DC grids from offshore wind power plants (OWPPs), connected through multi-terminal HVDC network. A coordinated control scheme where OWPP’s AC grid frequency modulated according to DC grid voltage variations is used...... to detect and provide the ancillary service requirements of both AC and DC grids, is proposed in this paper. In particular, control strategies for onshore frequency control, fault ridethrough support in the onshore grid, and DC grid voltage control are considered. The proposed control scheme involves only...... local measurements and therefore avoids the need of communication infrastructure otherwise required for communication based control, and thus increases the reliability of the control system. The effectiveness of the proposed control scheme is demonstrated on a MTDC connected wind power system developed...

  6. Computer Security: Protect your plant: a "serious game" about control system cyber-security

    CERN Multimedia

    Stefan Lueders, Computer Security Team

    2015-01-01

    Control system cyber-security is attracting increasing attention: from cybercriminals, from the media and from security researchers.   After the legendary “Stuxnet” attacks of 2010 against an Iranian uranium enrichment plant, the infiltration of Saudi Aramco in 2012, and most recently the hacking of German blast furnaces, we should be prepared. Just imagine what would happen if hackers turned off the lights in Geneva and the Pays-de-Gex for a month? (“Hacking control systems, switching lights off!"). Or if attackers infiltrated CERN’s accelerator or experiment control systems and stopped us from pursuing our core business: delivering beams and recording particle collisions (“Hacking control systems, switching... accelerators off?"). Now you can test your ability to protect an industrial plant against cyber-threats! The Computer Security Team, in collaboration with Kaspersky Lab, is organising a so-...

  7. Towards a benchmark simulation model for plant-wide control strategy performance evaluation of WWTPs

    DEFF Research Database (Denmark)

    Jeppsson, Ulf; Rosen, Christian; Alex, Jens;

    2006-01-01

    The COST/IWA benchmark simulation model has been available for seven years. Its primary purpose has been to create a platform for control strategy benchmarking of activated sludge processes. The fact that the benchmark has resulted in more than 100 publications, not only in Europe but also...... worldwide, demonstrates the interest in such a tool within the research community In this paper, an extension of the benchmark simulation model no 1 (BSM1) is proposed. This extension aims at facilitating control strategy development and performance evaluation at a plant-wide level and, consequently...... the changes, the evaluation period has been extended to one year. A prolonged evaluation period allows for long-term control strategies to be assessed and enables the use of control handles that cannot be evaluated in a realistic fashion in the one-week BSM1 evaluation period. In the paper, the extended plant...

  8. Near-term improvements for nuclear power plant control room annunciator systems. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Rankin, W.L.; Duvernoy, E.G.; Ames, K.R.; Morgenstern, M.H.; Eckenrode, R.J.

    1983-04-01

    This report sets forth a basic design philosophy with its associated functional criteria and design principles for present-day, hard-wired annunciator systems in the control rooms of nuclear power plants. It also presents a variety of annunciator design features that are either necessary for or useful to the implementation of the design philosophy. The information contained in this report is synthesized from an extensive literature review, from inspection and analysis of control room annunciator systems in the nuclear industry and in related industries, and from discussions with a variety of individuals who are knowledgeable about annunciator systems, nuclear plant control rooms, or both. This information should help licensees and license applicants in improving their hard-wired, control room annunciator systems as outlined by NUREG-0700.

  9. Plant phenology and composition controls of carbon fluxes in a boreal peatland

    Science.gov (United States)

    Peichl, Matthias; Gažovič, Michal; Vermeij, Ilse; De Goede, Eefje; Sonnentag, Oliver; Limpens, Juul; Nilsson, Mats B.

    2016-04-01

    Vegetation drives the peatland carbon (C) cycle via the processes of photosynthesis, plant respiration and decomposition as well as by providing substrate for methane (CH4) and dissolved organic carbon production. However, due to the lack of comprehensive vegetation data, variations in the peatland C fluxes are commonly related to temperature and other more easily measured abiotic (i.e. weather and soil) variables. Due to the temporal co-linearity between plant development and abiotic variables, these relationships may describe the variations in C fluxes reasonably well, however, without representing the true mechanistic processes driving the peatland C cycle. As a consequence, current process-based models are poorly parameterized and unable to adequately predict the responses of the peatland C cycle to climate change, extreme events and anthropogenic impacts. To fill this knowledge gap, we explored vegetation phenology and composition effects on the peatland C cycle at the Degerö peatland located in northern Sweden. We used a greenness index derived from digital repeat photography to quantitatively describe plant canopy development with high temporal (i.e. daily) and spatial (plot to ecosystem) resolution. In addition, eddy covariance and static chamber measurements of carbon dioxide (CO2) and CH4 fluxes over an array of vegetation manipulation plots were conducted over multiple years. Our results suggest that vascular plant phenology controls the onset and pattern of eddy covariance-derived gross primary production (GPP) during the spring period, while abiotic conditions modify GPP during the summer period when plant canopy cover is fully developed. Inter-annual variations in the spring onset and patterns of plant canopy development were best explained by differences in the preceding growing degree day sum. We also observed strong correlations of canopy greenness with the net ecosystem CO2 exchange and ecosystem respiration. On average, vascular plant and moss

  10. Advanced Grid-Friendly Controls Demonstration Project for Utility-Scale PV Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, Vahan [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Neill, Barbara [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-01-21

    A typical photovoltaic (PV) power plant consists of multiple power electronic inverters and can contribute to grid stability and reliability through sophisticated 'grid-friendly' controls. The availability and dissemination of actual test data showing the viability of advanced utility-scale PV controls among all industry stakeholders can leverage PV's value from being simply an energy resource to providing additional ancillary services that range from variability smoothing and frequency regulation to power quality. Strategically partnering with a selected utility and/or PV power plant operator is a key condition for a successful demonstration project. The U.S. Department of Energy's (DOE's) Solar Energy Technologies Office selected the National Renewable Energy Laboratory (NREL) to be a principal investigator in a two-year project with goals to (1) identify a potential partner(s), (2) develop a detailed scope of work and test plan for a field project to demonstrate the gird-friendly capabilities of utility-scale PV power plants, (3) facilitate conducting actual demonstration tests, and (4) disseminate test results among industry stakeholders via a joint NREL/DOE publication and participation in relevant technical conferences. The project implementation took place in FY 2014 and FY 2015. In FY14, NREL established collaborations with AES and First Solar Electric, LLC, to conduct demonstration testing on their utility-scale PV power plants in Puerto Rico and Texas, respectively, and developed test plans for each partner. Both Puerto Rico Electric Power Authority and the Electric Reliability Council of Texas expressed interest in this project because of the importance of such advanced controls for the reliable operation of their power systems under high penetration levels of variable renewable generation. During FY15, testing was completed on both plants, and a large amount of test data was produced and analyzed that demonstrates the ability of

  11. Is micro-CHP price controllable under price signal controlled Virtual Power Plants?

    DEFF Research Database (Denmark)

    You, Shi; Træholt, Chresten; Poulsen, Bjarne

    2011-01-01

    As micro-combined heat and power (micro-CHP) systems move towards mass deployment together with other kinds of distributed energy resources (DER), an increasing emphasis has been placed on how to coordinate such a large diversified DER portfolio in an efficient way by the Virtual Power Plant (VPP...

  12. Nice to meet you: genetic, epigenetic and metabolic controls of plant perception of beneficial associative and endophytic diazotrophic bacteria in non-leguminous plants.

    Science.gov (United States)

    Carvalho, T L G; Ballesteros, H G F; Thiebaut, F; Ferreira, P C G; Hemerly, A S

    2016-04-01

    A wide range of rhizosphere diazotrophic bacteria are able to establish beneficial associations with plants, being able to associate to root surfaces or even endophytically colonize plant tissues. In common, both associative and endophytic types of colonization can result in beneficial outcomes to the plant leading to plant growth promotion, as well as increase in tolerance against biotic and abiotic stresses. An intriguing question in such associations is how plant cell surface perceives signals from other living organisms, thus sorting pathogens from beneficial ones, to transduce this information and activate proper responses that will finally culminate in plant adaptations to optimize their growth rates. This review focuses on the recent advances in the understanding of genetic and epigenetic controls of plant-bacteria signaling and recognition during beneficial associations with associative and endophytic diazotrophic bacteria. Finally, we propose that "soil-rhizosphere-rhizoplane-endophytes-plant" could be considered as a single coordinated unit with dynamic components that integrate the plant with the environment to generate adaptive responses in plants to improve growth. The homeostasis of the whole system should recruit different levels of regulation, and recognition between the parties in a given environment might be one of the crucial factors coordinating these adaptive plant responses.

  13. A study of control strategies for a clarifier at an industry wastewater treatment plant

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Control of clarifier in the activated sludge process is critical for ensuring effective wastewater treatment. This paper is to study appropriate control strategies for a clarifier in an industrial wastewater treatment plant. Five control strategies are proposed, implemented and evaluated in a simulation software (West ++ ). The sludge blanket height and the effluent suspended solids concentration were proposed as the measured variable. The manipulated variable was the quantity of polymer added to the system. The strategies were evaluated in terms of their ability to maintain the sludge blanket height below 1.5m, their polymer requirements, their sensitivity to poor tuning and the required control action.

  14. 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.

  15. Coordinated Fast Primary Frequency Control from Offshore Wind Power Plants in MTDC System

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Hansen, Anca Daniela; Cutululis, Nicolaos Antonio

    2016-01-01

    In this paper, coordinated fast primary frequency control (FPFC) from offshore wind power plants (OWPPs) integrated to surrounding onshore AC power system through a three terminal VSC HVDC system is presented. The onshore AC grid frequency variations are emulated at offshore AC grid through...... and the dynamics of wind turbine are also discussed. The corresponding impact of OWPPs active power output variation at different wind speeds on the power system frequency control and DC grid voltage is also presented. The results show that the proposed coordinated fast primary frequency control from OWPPs...... improves the power system frequency while relieving the stress on the other AC grid participating in frequency control....

  16. W-026 acceptance test plan plant control system hardware (submittal {number_sign} 216)

    Energy Technology Data Exchange (ETDEWEB)

    Watson, T.L., Fluor Daniel Hanford

    1997-02-14

    Acceptance Testing of the WRAP 1 Plant Control System Hardware will be conducted throughout the construction of WRAP I with the final testing on the Process Area hardware being completed in November 1996. The hardware tests will be broken out by the following functional areas; Local Control Units, Operator Control Stations in the WRAP Control Room, DMS Server, PCS Server, Operator Interface Units, printers, DNS terminals, WRAP Local Area Network/Communications, and bar code equipment. This document will contain completed copies of each of the hardware tests along with the applicable test logs and completed test exception reports.

  17. W-026 acceptance test report plant control system hardware (submittal {number_sign} 220.C)

    Energy Technology Data Exchange (ETDEWEB)

    Watson, T.L., Fluor Daniel Hanford

    1997-02-14

    Acceptance Testing of the WRAP1 Plant Control System Hardware was conducted throughout the construction of WRAPI with the final testing on the Process Area hardware being completed in November 1996. The hardware tests were broken out by the following functional areas; Local Control Units, Operator Control Stations in the WRAP Control Room, DMS Server, PCS Server, Operator Interface Units, printers, DMS terminals, WRAP Local Area Network/Communications, and bar code equipment. This document contains a completed copy of each of the hardware tests along with the applicable test logs and completed test exception reports.

  18. Multi-criteria evaluation of wastewater treatment plant control strategies under uncertainty

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Rodriguez-Roda, Ignasi; Sin, Gürkan

    2008-01-01

    The evaluation of activated sludge control strategies in wastewater treatment plants (WWTP) via mathematical modelling is a complex activity because several objectives; e.g. economic, environmental, technical and legal; must be taken into account at the same time, i.e. the evaluation of the alter...

  19. Evaluating subsoiling and herbaceous weed control on shortleaf pine planted in retired farm land

    Science.gov (United States)

    John D. Kushla

    2010-01-01

    In March 2005, shortleaf pine was planted on retired fields of the Mississippi Agriculture and Forestry Experiment Station in Holly Springs. The objectives were to evaluate subsoiling and herbaceous weed control on first year seedling stocking, survival, and size. First year seedling measurements were made on stocking, survival, and size. Only results for first year...

  20. Dynamic Reactive Power Control in Offshore HVDC Connected Wind Power Plants

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Cutululis, Nicolaos Antonio; Rather, Zakir Hussain;

    2016-01-01

    This paper presents a coordinated reactive power control for a HVDC connected cluster of offshore wind power plants (WPPs). The reactive power reference for the WPP cluster is estimated by an optimization algorithm aiming at minimum active power losses in the offshore AC Grid. For each optimal...

  1. Sharka epidemiology and worldwide management strategies: learning lessons to optimize disease control in perennial plants

    Science.gov (United States)

    Many plant epidemics that cause major economic losses cannot be controlled with pesticides. Among them, sharka epidemics severely affect prunus trees worldwide. Its causal agent, Plum pox virus (PPV;, genus Potyvirus), has been classified as a quarantine pathogen in numerous countries. As a result, ...

  2. Pesticide Applicator Certification Training, Manual No. 1a: Agricultural Pest Control. a. Plant.

    Science.gov (United States)

    Allen, W. A.; And Others

    This manual provides information needed to meet the minimum standards for certification as an applicator of pesticides in the agricultural plant pest control category. Adapted for the State of Virginia, the text discusses: (1) the basics of insecticides; (2) insect pests; (3) selection and calibration of applicator equipment; and (4) the proper…

  3. A Control-Oriented Dynamic Model for Wakes in Wind Plants

    NARCIS (Netherlands)

    Gebraad, P.M.O.; Van Wingerden, J.W.

    2014-01-01

    In this paper, we present a novel control-oriented model for predicting wake effects in wind plants, called the FLOw Redirection and Induction Dynamics (FLORIDyn) model. The model predicts the wake locations and the effective flow velocities at each turbine, and the resulting turbine electrical

  4. Brassinosteroids, gibberellins and light-mediated signalling are the three-way controls of plant sprouting.

    Science.gov (United States)

    Jaillais, Yvon; Vert, Grégory

    2012-08-01

    The steroid hormones found in plants, the brassinosteroids, were originally genetically identified about 15 years ago as critical regulators of seedling photomorphogenesis. Two studies now shed light on the molecular mechanisms behind this observation. Brassinosteroids control seedling morphogenesis through direct interaction with master transcriptional regulators downstream of growth-promoting hormones and light signalling.

  5. Distributed voltage control coordination between renewable generation plants in MV distribution grids

    DEFF Research Database (Denmark)

    Petersen, Lennart; Iov, Florin

    2017-01-01

    This study focuses on distributed voltage control coordination between renewable generation plants in medium-voltage distribution grids (DGs). A distributed offline coordination concept has been defined in a previous publication, leading to satisfactory voltage regulation in the DG. However, here...

  6. Potential Use of Chlorine Dioxide to Control Diseases in Ornamental Plant Production Systems

    Science.gov (United States)

    Research is being done to evaluate uses of chlorine dioxide in ornamental plant production systems. Chlorine dioxide has been shown to control spread of Fusarium oxysporum during the hot water treatment of daffodils and should provide replacement of formaldehyde which was used in the past. By dipp...

  7. Optimised Control of 10 MW Photovoltaic (PV) Plant with 1MW / 1MWh Battery

    DEFF Research Database (Denmark)

    Nørgård, Per Bromand; Bindner, Henrik W.; Thavlov, Anders

    2016-01-01

    MWp PV capacity and 1MW/1MWh battery storage at the campus. This paper presents the specific context of the power system in Cyprus and the future UCY microgrid along with the possible and expected impacts of the PV plant and Battery Energy Storage System. The battery control strategies are tested...

  8. Proportional derivative based stabilizing control of paralleled grid converters with cables in renewable power plants

    DEFF Research Database (Denmark)

    Wang, Xiongfei; Blaabjerg, Frede; Loh, Poh Chiang

    2014-01-01

    Resonant interactions of grid-connected converters with each other and with cable capacitance are challenging the stability and power quality of renewable energy sources based power plants. This paper addresses the instability of current control of converters with the multiple resonance frequenci...

  9. Releasable Kinetic Energy-Based Inertial Control of a DFIG Wind Power Plant

    DEFF Research Database (Denmark)

    Lee, Jinsik; Muljadi, Eduard; Sørensen, Poul Ejnar

    2016-01-01

    Wind turbine generators (WTGs) in a wind power plant (WPP) contain different levels of releasable kinetic energy (KE) because of the wake effects. This paper proposes a releasable KE-based inertial control scheme for a doubly fed induction generator (DFIG) WPP that differentiates the contributions...

  10. Proceedings of the 1978 symposium on instrumentation and control for fossil demonstration plants

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    The 1978 symposium on instrumentation and control for fossil demonstration plants was held at Newport Beach, California, June 19--21, 1978. It was sponsored by Argonne National Laboratory, the U.S. Department of Energy - Fossil Energy, and the Instrument Society of America - Orange County Section. Thirty-nine papers have been entered individually into the data base. (LTN)

  11. Unraveling transcriptional and translational control in plant energy homeostasis : a bioinformatic approach

    NARCIS (Netherlands)

    Peviani, A.

    2016-01-01

    Due to their sessile nature, plants require a tight regulation of energy homeostasis in order to survive and reproduce in changing environmental conditions. Regulation of gene expression is controlled at several levels, from transcription to translation and beyond. Sugars themselves can act directly

  12. Genetic control of plant development by overriding a geometric division rule

    NARCIS (Netherlands)

    Yoshida, S.; Barbier de Reuille, P.; Lane, B.; Bassel, G.W.; Prusinkiewicz, P.; Smith, R.S.; Weijers, D.

    2014-01-01

    Formative cell divisions are critical for multicellular patterning. In the early plant embryo, such divisions follow from orienting the division plane. A major unanswered question is how division plane orientation is genetically controlled, and in particular whether this relates to cell geometry. We

  13. New 2DOF PI and PID Controllers Tuning Method for Integrating Plants

    Directory of Open Access Journals (Sweden)

    Miluše VÍTEČKOVÁ

    2009-07-01

    Full Text Available The paper deals with a new 2DOF PI and PID controllers tuning method for integrating plants. The described approach is derived from the multiple dominant pole method and it enables the achievement of an aperiodic servo and regulatory step responses.

  14. Ten-Year Growth of Five Planted Hardwood Species Mechanical Weed Control on Sharkey Clay Soil

    Science.gov (United States)

    Roger M. Krinard; Harvey E. Kennedy

    1983-01-01

    Five hardwood species planted on Sharkey clay soil showed little practical difference in growth whether plots were mowed or diskedfor weed control in years 6 to 10, although disking had given better growth in the first 5 years. After 10 years, cottonwood (Populus deltoides Bartr. ex Marsh.) stem volume was at least three times greater than other species. Changes in...

  15. Modern on-line control system for refuse-fueled power plants. Moderne Leittechnik fuer Muellverbrennungsanlage

    Energy Technology Data Exchange (ETDEWEB)

    Grasmueck, L. (Asea Brown Boveri AG, Mannheim (Germany, F.R.)); Klitzke, H.J. (Goepfert und Reimer und Partner, Beratende Ingenieure, Hamburg (Germany, F.R.)); Schumacher, E. (Technische Werke Ludwigshafen am Rhein AG (Germany, F.R.))

    1989-10-01

    30 years after commissioning a refuse-fueled power plant in Ludwigshafen was retrofitted and extended. A process control system provides an optimal waste combustion and flue gas cleanup. An on-line central strategy, special requirements on waste combustion and solutions are presented in this report. (orig.).

  16. Fault Monitoring and Re-Configurable Control for a Ship Propulsion Plant

    DEFF Research Database (Denmark)

    Blanke, M.; Izadi-Zamanabadi, Roozbeh; Lootsma, T.F.

    1998-01-01

    Minor faults in ship propulsion and their associated automation systems can cause dramatic reduction on ships' ability to propel and manoeuvre, and effective means are needed to prevent that simple faults develop into severe failure. The paper analyses the control system for a propulsion plant...

  17. Post-Plant nematicides for the control of root lesion nematode in red raspberry

    Science.gov (United States)

    There are currently few registered post-plant nematicides available to control root lesion nematode (Pratylenchus penetrans, RLN) in red raspberry (Rubus ideaus). The rate of raspberry decline due to RLN depends upon the nematode population density but usually occurs over a 3- to 4-year period. To ...

  18. The discovery of fluazaindolizine: A new product for the control of plant parasitic nematodes.

    Science.gov (United States)

    Lahm, George P; Desaeger, Johan; Smith, Ben K; Pahutski, Thomas F; Rivera, Michel A; Meloro, Tony; Kucharczyk, Roman; Lett, Renee M; Daly, Anne; Smith, Brenton T; Cordova, Daniel; Thoden, Tim; Wiles, John A

    2017-04-01

    Fluazaindolizine is a new highly effective and selective product for the control of plant parasitic nematodes. Specificity for nematodes coupled with absence of activity against the target sites of commercial nematicides suggests that fluazaindolizine has a novel mode of action. The discovery, structure-activity development and biological properties for this new class of nematicides are presented.

  19. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Fang, Jiakun;

    2013-01-01

    This paper presents a simulation model of a wind power plant based on a MW-level variable speed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory. Three different kinds of ancillary frequency control strategies, namely inertia ...

  20. Genetic control of plant development by overriding a geometric division rule

    NARCIS (Netherlands)

    Yoshida, S.; Barbier de Reuille, P.; Lane, B.; Bassel, G.W.; Prusinkiewicz, P.; Smith, R.S.; Weijers, D.

    2014-01-01

    Formative cell divisions are critical for multicellular patterning. In the early plant embryo, such divisions follow from orienting the division plane. A major unanswered question is how division plane orientation is genetically controlled, and in particular whether this relates to cell geometry. We