916 resultados para Unbalanced operation of diode-clamped three-level inverter


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We describe remarkable success in controlling dengue vectors, Aedes aegypti (L.) and Aedes albopictus (Skuse), in 6 communes with 11,675 households and 49,647 people in the northern provinces of Haiphong, Hung Yen, and Nam Dinh in Vietnam. The communes were selected for high-frequency use of large outdoor concrete tanks and wells. These were found to be the source of 49.6-98.4% of Ae. aegypti larvae, which were amenable to treatment with local Mesocyclops, mainly M. woutersi Van der Velde, M. aspericornis (Daday) and M. thermocyclopoides Harada. Knowledge, attitude, and practice surveys were performed to determine whether the communities viewed dengue and dengue hemorrhagic fever as a serious health threat; to determine their knowledge of the etiology, attitudes, and practices regarding control methods including Mesocyclops; and to determine their receptivity to various information methods. On the basis of the knowledge, attitude, and practice data, the community-based dengue control program comprised a system of local leaders, health volunteer teachers, and schoolchildren, supported by health professionals. Recycling of discards for economic gain was enhanced, where appropriate, and this, plus 37 clean-up campaigns, removed small containers unsuitable for Mesocyclops treatment. A previously successful eradication at Phan Boi village (Hung Yen province) was extended to 7 other villages forming Di Su commune (1,750 households) in the current study. Complete control was also achieved in Nghia Hiep (Hung Yen province) and in Xuan Phong (Nam Dinh province); control efficacy was greater than or equal to 99.7% in the other 3 communes (Lac Vien in Haiphong, Nghia Dong, and Xuan Kien in Nam Dinh). Although tanks and wells were the key container types of Ae. aegypti productivity, discarded materials were the source of 51% of the standing crop of Ae. albopictus. Aedes albopictus larvae were eliminated from the 3 Nam Dinh communes, and 86-98% control was achieved in the other 3 communes. Variable dengue attack rates made the clinical and serological comparison of control and untreated communes problematic, but these data indicate that clinical surveillance by itself is inadequate to monitor dengue transmission.

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1. Tiger snake antivenom, raised against Notechis scutatus venom, is indicated not only for the treatment of envenomation by this snake, but also that of the copperhead (Austrelaps superbus ) and Stephen's banded snake (Hoplocephalus stephensi ). The present study compared the neuromuscular pharmacology of venom from these snakes and the in vitro efficacy of tiger snake antivenom. 2. In chick biventer cervicis muscle and mouse phrenic nerve diaphragm preparations, all venoms (3-10 mug/mL) produced inhibition of indirect twitches. In the biventer muscle, venoms (10 mug/mL) inhibited responses to acetylcholine (1 mmol/L) and carbachol (20 mumol/L), but not KCl (40 mmol/L). The prior (10 min) administration of 1 unit/mL antivenom markedly attenuated the neurotoxic effects of A. superbus and N. scutatus venoms (10 mug/mL), but was less effective against H. stephensi venom (10 mug/mL); 5 units/mL antivenom attenuated the neurotoxic activity of all venoms. 3. Administration of 5 units/mL antivenom at t(90) partially reversed, over a period of 3 h, the inhibition of twitches produced by N. scutatus (10 mug/mL; 41% recovery), A. superbus (10 mug/mL; 25% recovery) and H. stephensi (10 mug/mL; 50% recovery) venoms. All venoms (10-100 mug/mL) also displayed signs of in vitro myotoxicity. 4. The results of the present study indicate that all three venoms contain neurotoxic activity that is effectively attenuated by tiger snake antivenom.

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A robot’s drive has to exert appropriate driving forces that can keep its arm and end effector at the proper position, velocity and acceleration, and simultaneously has to compensate for the effects of the contact forces arising between the tool and the workpiece depending on the needs of the actual technological operation. Balancing the effects of a priori unknown external disturbance forces and the inaccuracies of the available dynamic model of the robot is also important. Technological tasks requiring well prescribed end effector trajectories and contact forces simultaneously are challenging control problems that can be tackled in various manners.

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The participation of the Fraunhofer Institute for Manufacturing Engineering and Automation IPA (Stuttgart, Germany) and the companies User Interface Design GmbH (Ludwigsburg, Germany) plus MLR System GmbH (Ludwigsburg, Germany) enabled the research and findings presented in this paper; we would like to namely mention Birgit Graf and Theo Jacobs (Fraunhofer IPA) furthermore Peter Klein and Christiane Hartmann (User Interface Design GmbH).

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This paper presents a new communication architecture to enable the remote control, monitoring and debug of embedded-system controllers designed using IOPT Petri nets. IOPT Petri nets and the related tools (http://gres.uninova.pt) have been used as a rapid prototyping and development framework, including model-checking, simulation and automatic code generation tools. The new architecture adds remote operation capabilities to the controllers produced by the automatic code generators, enabling quasi-real-time remote debugging and monitoring using the IOPT simulator tool. Furthermore, it enables the creation of graphical user interfaces for remote operation and the development of distributed systems where a Petri net model running on a central system supervises the actions of multiple remote subsystems. © 2015 IEEE.

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Pinworm infection was prospectively studied during one year in 469 children attending three day care centers. Each child was examined at six months intervals using up to three perianal swabs with adhesive tape. Those found infected were treated with mebendazole. At the beginning of the study we found a prevalence of 28% that dropped to 13% and 12% in the following study periods. The reinfection rate was twice the incidence rate in both study periods. We also found a small percentage (10%) of the children reinfected in most or all study periods. There was a high correlation between reinfection and perianal itching. Our results add further knowledge to the epidemiology of intestinal parasites in day care centers.

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The hantavirus pulmonary syndrome was first recognized in cases that occurred in the U.S. in 1993, which served as an alert not only for American physicians but also for physicians in other countries for the identification of the disease. In the city of São Paulo, Brazil, 3 cases of the syndrome were recorded in 1993. The patients were young brothers residing in the Mata Atlântica (Atlantic Forest) region submitted to recent deforestation. Two of the patients died of acute respiratory insufficiency and the third recovered without sequelae. In the surviving patient the diagnosis was established by a laboratory criterion based on the detection of specific IgM and IgG class antibodies by indirect immunofluorescence. In the two patients who died, the diagnosis was confirmed by laboratory tests using immunoperoxidase technique for hantavirus in tissue, in histological lung and heart sections in one case, and by clinical and epidemiological data in the other

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Background: Children with Gaucher disease type I (GD1) are usually treated with enzyme replacement therapy (ERT) at a dose of 30-60U/Kg/2W. Recently, due to an acute shortage supply of imiglucerase, a reduced dose or a reduced infusion frequency was recommended. Objective: To evaluate the effects of a reduced infusion frequency of imiglucerase over 15 months of follow-up. Patients and Methods: Three patients (1M:2F) were treated with ERT since a median age of 7 years (range 5-12). Only one had bone crisis and Erlenmeyer deformations. Median duration of treatment before dose reduction was 3 years (range 1-8). ERT resulted in total regression of symptoms, normalization of hematological parameters and progressive improvement of chitotriosidase in all patients. In August 2009 infusion schedule was changed from a media 45U/Kg every two weeks to every four weeks. Results: All patients remained asymptomatic and with no major change on hematological parameters except for the patient with bone crisis who presented subnormal platelet count. All patients showed an upward trend in chitotriosidase values. Comments: Although a longer follow-up is needed, is probable that even children completely stabilized can probably not be kept on lower doses even though the reduction of frequency of the infusions represent a lower social burden.

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Simulated moving bed (SMB) chromatography is attracting more and more attention since it is a powerful technique for complex separation tasks. Nowadays, more than 60% of preparative SMB units are installed in the pharmaceutical and in the food in- dustry [SDI, Preparative and Process Liquid Chromatography: The Future of Process Separations, International Strategic Directions, Los Angeles, USA, 2002. http://www. strategicdirections.com]. Chromatography is the method of choice in these ¯elds, be- cause often pharmaceuticals and ¯ne-chemicals have physico-chemical properties which di®er little from those of the by-products, and they may be thermally instable. In these cases, standard separation techniques as distillation and extraction are not applicable. The noteworthiness of preparative chromatography, particulary SMB process, as a sep- aration and puri¯cation process in the above mentioned industries has been increasing, due to its °exibility, energy e±ciency and higher product purity performance. Consequently, a new SMB paradigm is requested by the large number of potential small- scale applications of the SMB technology, which exploits the °exibility and versatility of the technology. In this new SMB paradigm, a number of possibilities for improving SMB performance through variation of parameters during a switching interval, are pushing the trend toward the use of units with smaller number of columns because less stationary phase is used and the setup is more economical. This is especially important for the phar- maceutical industry, where SMBs are seen as multipurpose units that can be applied to di®erent separations in all stages of the drug-development cycle. In order to reduce the experimental e®ort and accordingly the coast associated with the development of separation processes, simulation models are intensively used. One impor- tant aspect in this context refers to the determination of the adsorption isotherms in SMB chromatography, where separations are usually carried out under strongly nonlinear conditions in order to achieve higher productivities. The accurate determination of the competitive adsorption equilibrium of the enantiomeric species is thus of fundamental importance to allow computer-assisted optimization or process scale-up. Two major SMB operating problems are apparent at production scale: the assessment of product quality and the maintenance of long-term stable and controlled operation. Constraints regarding product purity, dictated by pharmaceutical and food regulatory organizations, have drastically increased the demand for product quality control. The strict imposed regulations are increasing the need for developing optically pure drugs.(...)

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This paper deals with a computing simulation for an offshore wind energy system taking into account the influence of the marine waves action throughout the floating platform. The wind energy system has a variable-speed turbine equipped with a permanent magnet synchronous generator and a full-power five level converter, injecting energy into the electric grid through a high voltage alternate current link. A reduction on the unbalance of the voltage in the DC-link capacitors of the five-level converter is proposed by a strategic selection of the output voltage vectors. The model for the drive train of the wind energy system is a two mass model, including the dynamics of the floating platform. A case study is presented and the assessment of the quality of the energy injected into the electric grid is discussed.

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¿Qué formas adquieren los cuerpos de los jóvenes bajo las actuales condiciones de producción? ¿Cuáles son sus poéticas? ¿Qué relaciones de fuerza se realizan en estas formas? ¿Cómo se inscriben en los cuerpos las relaciones de dominación, el "ethos" y la cosmovisión de un grupo social? Estas son algunas de las cuestiones que orientan el presente proyecto, interesado en explorar y describir sistemáticamente los procesos sociales del devenir "joven" en Córdoba. La investigación aborda algunas de las problemáticas propias de los jóvenes en tanto grupo social heterogéneo y diferenciado a partir del análisis de las prácticas de producción, consumo, interpretación y circulación de bienes culturales asociados con la diversión y el tiempo libre. Los tres objetos empíricos, localizados en la ciudad de Córdoba, son:o las salidas nocturnas de jóvenes estudiantes universitarios o la formación y el entrenamiento de los bailarines clásicos en el Teatro del Libertador Gral. San Martín. o las prácticas de entretenimiento y socialización lúdica entre los jóvenes de la comunidad de sordos de Córdoba.La hipótesis central de la investigación sostiene que la música y el baile tienen la capacidad de producir las identidades que nombran. Esta producción de cuerpos y subjetividades se realizaría en las performances sociales ("las salidas nocturnas" y "fiestas de la comunidad sorda") y las performances artísticas (clases, ensayos y funciones de ballet) donde se da la interacción entre las identidades actuadas por los sujetos y las ofrecidas por las diferentes músicas, bailes y movimientos corporales. En este sentido, proponemos que las performances articulan una particular identidad cuando quienes la protagonizan experimentan que la música y el baile se "ajusta" a la trama argumental que organiza sus narrativas identitarias.ObjetivosGENERAL:o Describir, de modo denso, las prácticas y representaciones implicadas en el proceso de materialización de los cuerpos y relacionarlas con los procesos de subjetivación y formación de identidades juveniles. ESPECÍFICOS.o Explorar la relación entre las diversas formas de consumo cultural en la formación de un estilo de vida y en la formación de identidades colectivas. o Describir los procesos de entrenamiento de los bailarines de música clásica.o Analizar los procesos de comunicación no verbal entre jóvenes de la comunidad sorda.Materiales y métodos.Para realizar esta investigación se construirá por medio de técnicas cuali y cuantitativas un corpus heterogéneo de materiales textuales, gráficos y audiovisuales, así como de entrevistas en profundidad, de experiencias etnográficas de observación participante y de investigación cuantitativa. Dicho corpus recibirá un tratamiento diferencial según el soporte y género, pero en todos los casos trabajando desde una matriz de análisis que considere los procesos de construcción de sentido y las relaciones entre cuerpo, subjetividad e identidad. En el análisis de los datos se pondrán en juego herramientas conceptuales tomadas de la Antropología Simbólica, la Antropología de la Danza, el Análisis del Discurso, la Sociología del Arte y los Estudios de la Performance. Resultados esperados.Se espera elaborar indicadores para medir la producción, circulación y consumo de bienes simbólicos. El desenvolvimiento del proyecto permitirá también la formación de recursos humanos en investigación y se contempla presentaciones a reuniones científicas, publicación en revistas nacionales e internacionales y la elaboración de dos libros. Por último se implementarán actividades de capacitación y asesoramiento para instituciones relacionados con los jóvenes. Importancia del ProyectoLos resultados de la investigación permitirán una interpretación más comprehensiva de los sentidos que poseen para jóvenes cordobeses problemáticas sociales como las adicciones, el alcoholismo, la salud sexual y reproductiva, las prácticas discriminatorias o los usos de las nuevas tecnologías.