Sistema portátil de medida de dispositivos sometidos a ensayos en campo

El proyecto fin de carrera “Sistema Portátil de Medida de Dispositivos Sometidos a Ensayos en Campo” es un proyecto acometido para el desarrollo y evaluación de un sistema de medición portátil y confiable, que permita la realización de mediciones de curvas I-V en campo, en condiciones reales de funcionamiento. Dado que la finalidad de este proyecto fin de carrera es la obtención de un sistema para la realización de mediciones en campo, en la implementación del proyecto se tendrán como requisitos principales de diseño el tamaño, la fuente de alimentación, el peso del sistema, además de la fiabilidad y una relativa precisión en la realización de mediciones. Durante la realización de este proyecto y dados los requerimientos anteriores de portabilidad y fiabilidad, se ha buscado ofrecer una solución de compromiso diseñando un equipamiento que sea realizable, que cumpla con los objetivos anteriores con un coste que no sea elevado y con la característica de que disponga de una facilidad de manejo que permita a cualquier usuario la utilización del mismo. El sistema final diseñado está basado en el dispositivo de adquisición de datos MyDAQ de National Instruments que permite la realización de múltiples tipos de mediciones. En base a este dispositivo de adquisición de datos, se ha diseñado un sistema de medición con una arquitectura que se implementa a través de un ordenador portátil, con un software de medición instalado que recopila e interpreta los datos, y que alimenta y controla al dispositivo a través del puerto USB. El sistema también implementa una carga variable que permite la medición de la curva I-V en iluminación de células o mini-paneles fotovoltaicos. Este diseño permite que para la realización de las mediciones de las curvas I-V en iluminación en campo sólo se requiera conectar el dispositivo de adquisición a un PC portátil con batería y a la carga variable. Aunque este diseño es específico para la medición de células solares se ha implementado de forma que pueda extrapolarse fácilmente a otro tipo de medición de tensión y corriente. Para la comprobación de la precisión del sistema portátil de medidas, durante el proyecto se ha procedido a la comparación de los resultados obtenidos del sistema diseñado con un equipo de caracterización en laboratorio. Dicho sistema de alta exactitud permite cuantificar la degradación real de la célula y establecer una comparación de mediciones con el sistema portátil de medida, ofreciendo resultados satisfactorios en todas las mediciones realizadas y permitiendo concluir la evaluación del sistema portátil como apto para las mediciones de dispositivos en campo. El proceso de evaluación del equipamiento diseñado consistiría en la medida de la curva I-V en laboratorio de un dispositivo fotovoltaico con instrumentación de alta precisión y condiciones controladas de luz y temperatura de un dispositivo, célula o mini-panel. Tras la medida inicial las células se instalarían en campo y se realizaría una caracterización periódica de los dispositivos mediante el sistema portátil de medida, que permitiría evidenciar si en la curva I-V bajo iluminación existe degradación, y en qué zona de la curva. Al finalizar el ensayo o en periodos intermedios se desmontarían los dispositivos para volver a medir la curva I-V con exactitud en laboratorio. Por tanto el sistema portátil de medida, debe permitir evaluar la evolución de la curva I-V en condiciones ambientales similares a obtenidas en medidas anteriores, y a partir de la misma determinar el modo de degradación del dispositivo, no siendo necesaria una elevada precisión de medida para ofrecer resultados exactos de degradación, que sólo podrán medirse en el laboratorio. ABSTRACT. The final degree project "Portable Measurement System For Devices Under Field Tests" is a project undertaken for the development and evaluation of portable and reliable measurement equipment, which allows the realization of I-V curve measurements in field conditions actual operation. Since the purpose of this final project is to obtain a system for conducting field measurements in the implementation of the project will have as main design requirements for size, power supply, system weight, plus reliability and precision relative to the taking of measurements. During the development of this project and given the above requirements portability and reliability, has sought to offer a compromise designing equipment that is achievable, that meets the above objectives with a cost that is not high and the feature that available management facility that allows any user to use it. The final system is designed based on the acquisition device MyDAQ NI data that allows the execution of multiple types of measurements. Based on this data acquisition device, we have designed a measurement system with an architecture that is implemented via a laptop, with measurement software installed that collects and interprets data, and feeds and controls the device through the USB port. The system also implements a variable load which allows measurement of the I-V curve lighting photovoltaic cells. This design allows performing measurements of I-V curves in lighting field is only required to connect the device to purchase a laptop with a battery and variable load. Although this design is specific for the measurement of solar cells has been implemented so that it can easily be extrapolated to other types of measuring voltage and current. To test the accuracy of the portable measurement system during the project has been carried out to compare the results of the designed system, a team of laboratory characterization. This system of high accuracy to quantify the actual degradation of the cell and a comparison of measurements with portable measurement system, providing satisfactory results in all measurements and allowing complete portable system assessment as suitable for measurements of devices field. The evaluation process designed equipment would be far laboratory I-V curve of a photovoltaic device with high precision instrumentation controlled light and temperature of a device, panel or mini-cell conditions. After initial measurement cells settle in a periodic field and device characterization will be achieved through the portable measurement system, which would show whether the I-V curve under illumination degradation exists, and in which area of the curve. At the end of the trial or in interim periods devices to remeasure the I-V curve accurately in laboratory dismount. Therefore the portable measurement system should allow evaluating the evolution of the I-V curve similar to previous measurements obtained in ambient conditions, and from it determine the mode of degradation of the device, not a high measurement accuracy to be necessary to provide degradation accurate results, which can only be measured in the laboratory.

Oxímetro de pulso com comunicação via Bluetooth

Dissertação (mestrado)—Universidade de Brasília, Faculdade Gama, Programa de Pós-Graduação em Engenharia Biomédica, 2015.

Metamorfose planar via métodos Level Set e Particle Level Set para a reconstrução de superfícies tridimensionais

Evolving interfaces were initially focused on solutions to scientific problems in Fluid Dynamics. With the advent of the more robust modeling provided by Level Set method, their original boundaries of applicability were extended. Specifically to the Geometric Modeling area, works published until then, relating Level Set to tridimensional surface reconstruction, centered themselves on reconstruction from a data cloud dispersed in space; the approach based on parallel planar slices transversal to the object to be reconstructed is still incipient. Based on this fact, the present work proposes to analyse the feasibility of Level Set to tridimensional reconstruction, offering a methodology that simultaneously integrates the proved efficient ideas already published about such approximation and the proposals to process the inherent limitations of the method not satisfactorily treated yet, in particular the excessive smoothing of fine characteristics of contours evolving under Level Set. In relation to this, the application of the variant Particle Level Set is suggested as a solution, for its intrinsic proved capability to preserve mass of dynamic fronts. At the end, synthetic and real data sets are used to evaluate the presented tridimensional surface reconstruction methodology qualitatively.

Metamorfose planar via métodos Level Set e Particle Level Set para a reconstrução de superfícies tridimensionais

Evolving interfaces were initially focused on solutions to scientific problems in Fluid Dynamics. With the advent of the more robust modeling provided by Level Set method, their original boundaries of applicability were extended. Specifically to the Geometric Modeling area, works published until then, relating Level Set to tridimensional surface reconstruction, centered themselves on reconstruction from a data cloud dispersed in space; the approach based on parallel planar slices transversal to the object to be reconstructed is still incipient. Based on this fact, the present work proposes to analyse the feasibility of Level Set to tridimensional reconstruction, offering a methodology that simultaneously integrates the proved efficient ideas already published about such approximation and the proposals to process the inherent limitations of the method not satisfactorily treated yet, in particular the excessive smoothing of fine characteristics of contours evolving under Level Set. In relation to this, the application of the variant Particle Level Set is suggested as a solution, for its intrinsic proved capability to preserve mass of dynamic fronts. At the end, synthetic and real data sets are used to evaluate the presented tridimensional surface reconstruction methodology qualitatively.

LEUCINE ATTENUATES SKELETAL MUSCLE WASTING VIA INHIBITION OF UBIQUITIN LIGASES

The aim of this study was to assess the effect of leucine supplementation on elements of the ubiquitin proteasome system (UPS) in rat skeletal muscle during immobilization. This effect was evaluated by submitting the animals to a leucine supplementation protocol during hindlimb immobilization, after which different parameters were determined, including: muscle mass; cross-sectional area (CSA); gene expression of E3 ligases/deubiquitinating enzymes; content of ubiquitinated proteins; and rate of protein synthesis. Our results show that leucine supplementation attenuates soleus muscle mass loss driven by immobilization. In addition, the marked decrease in the CSA in soleus muscle type I fibers, but not type II fibers, induced by immobilization was minimized by leucine feeding. Interestingly, leucine supplementation severely minimized the early transient increase in E3 ligase [muscle ring finger 1 (MuRF1) and muscle atrophy F-box (MAFbx)/atrogin-1] gene expression observed during immobilization. The reduced peak of E3 ligase gene expression was paralleled by a decreased content of ubiquitinated proteins during leucine feeding. The protein synthesis rate decreased by immobilization and was not affected by leucine supplementation. Our results strongly suggest that leucine supplementation attenuates muscle wasting induced by immobilization via minimizing gene expression of E3 ligases, which consequently could downregulate UPS-driven protein degradation. It is notable that leucine supplementation does not restore decreased protein synthesis driven by immobilization. Muscle Nerve 41: 800-808, 2010

Public health implications of new guidelines for lead in drinking water: a case study in an area with historically high water lead levels

Concern about the neurotoxicity of lead, particularly in infants and young children, has led to a revision of blood lead levels which are considered to involve an acceptable level of human exposure. Drinking water guidelines have also been reviewed in order to reduce this source of population exposure to lead. In the last 20 years, guidelines have been reduced from 100 to 50 to 10 mu g/litre. Lead in tap water used to be a major public health problem in Glasgow because of the high prevalence of houses with lead service pipes, the low pH of the public water supply and the resulting high levels of lead in water used for public consumption. Following two separate programmes of water treatment, involving the addition of lime and, a decade later, lime supplemented with orthophosphate, it is considered that maximal measures have been taken to reduce lead exposure by chemical treatment of the water supply. Any residual problem of public exposure would require large scale replacement of lead service pipes. In anticipation of the more stringent limits for lead in drinking water, we set out to measure current lead exposure From tap water in the population of Glasgow served by the Loch Katrine water supply. to compare the current situation with 12 years previously and to assess the public health implications of different limits. The study was based on mothers of young children since maternal blood lead concentrations and the domestic water that mothers use to prepare bottle feeds are the principal sources of foetal and infant lead exposure. An estimated 17% of mothers lived in households with tap water lead concentrations of 10 mu g/litre (the WHO guideline) or above in 1993 compared with 49% in 1981. Mean maternal blood lead concentrations fell by 69% in 12 years. For a given water lead concentration, maternal blood lead concentrations were 67% lower. The mean maternal blood lead concentration was 3.7 mu g/litre in the population at large, compared with 3.3 mu g/litre in households with negligible or absent tap water lead. Nevertheless, between 63% and 76% of cases of mothers with blood lead concentrations of 10 mu g/dl or above were attributable to tap water lead. The study found that maternal blood lead concentrations were well within limits currently considered safe for human health. About 15% of infants may be exposed via bottle feeds to tap water lead concentrations that exceed the WHO guideline of 10 mu g/litre. In the context of the health and social problems which affect the well-being and development of infants and children in Glasgow, however, current levels of lend exposure are considered to present a relatively minor health problem. (C) 2000 Elsevier Science Ltd. All rights reserved.

Conditioned fear is modulated by D(2) receptor pathway connecting the ventral tegmental area and basolateral amygdala

Excitation of the mesocorticolimbic pathway, originating from dopaminergic neurons in the ventral tegmental area (VTA), may be important for the development of exaggerated fear responding. Among the forebrain regions innervated by this pathway, the amygdala is an essential component of the neural circuitry of conditioned fear. The functional role of the dopaminergic pathway connecting the VIA to the basolateral amygdala (BLA) in fear and anxiety has received little attention. In vivo microdialysis was performed to measure dopamine levels in the BLA of Wistar rats that received the dopamine D(2) agonist quinpirole (1 mu g/0.2 mu l) into the VTA and were subjected to a fear conditioning test using a light as the conditioned stimulus (CS). The effects of intra-BLA injections of the D(1) antagonist SCH 23390 (1 and 2 mu g/0.2 mu l) and D(2) antagonist sulpiride (1 and 2 mu g/0.2 mu l) on fear-potentiated startle (FPS) to a light-CS were also assessed. Locomotor performance was evaluated by use of open-field and rotarod tests. Freezing and increased dopamine levels in the BLA in response to the CS were both inhibited by intra-VTA quinpirole. Whereas intra-BLA SCH 23390 did not affect FPS, intra-BLA sulpiride (2 mu g) inhibited FPS. Sulpiride`s ability to decrease FPS cannot be attributed to nonspecific effects because this drug did not affect motor performance. These findings indicate that the dopamine D(2) receptor pathway connecting the ventral tegmental area and the basolateral amygdala modulates fear and anxiety and may be a novel pharmacological target for the treatment of anxiety. (C) 2010 Elsevier Inc. All rights reserved.

Tillering in grain sorghum over a wide range of population densities: Identification of a common hierarchy for tiller emergence, leaf area development and fertility

Most studies of tiller development have not related the physiological and morphological features of each calm to its subsequent fertility. This introduced problems when trying to account for the effects of tillering on yield in crop models. The objective of this study was to detect the most likely early determinants of tiller fertility in sorghum by identifying hierarchies for emergence, fertility and grain number of tillers over a wide range of assimilate availabilities. Emergence, phenology, leaf area development and dry weight partitioning were quantified weekly for individual tillers and main culms of tillering and uniculm plants grown at one of four densities, from two to 16 plants m(-2). For a given plant in any given density, the same tiller hierarchy applied for emergence of tillers, fertility of the emerged tillers and their subsequent grain number. These results were observed over a range of tiller fertility rates (from 7 to 91%), fertile tiller number per plant at maturity (from 0.2 to 4.7), and tiller contribution to grain yield (from 5 to 78%). Tiller emergence was most probably related to assimilate supply and light quality. Development, fertility and contribution to yield of a specific tiller were highly dependent on growing conditions at the time of tiller emergence, particularly via early leaf area development of the tiller, which affected its subsequent leaf area accumulation. Assimilate availability in the main culm at the time of tiller emergence was the most likely early determinant of subsequent tiller fertility in this study. (C) 2002 Annals of Botany Company.

The coincidence of thrips and dispersed pollen in PNRSV-infected stonefruit orchards - a precondition for thrips-mediated transmission via infected pollen

Recent laboratory studies have demonstrated that Prunus necrotic ringspot virus (PNRSV) (family Bromoviridae) can be readily transmitted when thrips and virus-bearing pollen are placed together on to test plants. For this transmission mechanism to result in stonefruit tree infection in the field, PNRSV-bearing pollen must be deposited onto surfaces of stonefruit trees on which thrips also occur. In a previous paper, we demonstrated that almost all pollen in a PNRSV-infected Japanese plum orchard in southeastern Queensland was deposited onto flowers, whereas few grains occurred on leaves and none on stems. Here, we present results of our investigation of thrips species composition, distribution and abundance on stonefruit trees in the same study area as our previous pollen deposition study. We collected a total of 2010 adult thrips from 13 orchards during the 1989, 1991 and 1992 flowering seasons of which all but 14 were in the suborder Terebrantia. Most (97.4%) terebrantian thrips were of three species, Thrips imaginis, Thrips australis and Thrips tabaci. Thrips tabaci as well as species mixtures that included T imaginis, T australis and T tabaci have been shown to transmit PNRSV via infected pollen in laboratory tests. Adult thrips were frequently collected from flowers but rarely from leaves and never from stems. Large and significant differences in numbers of T imaginis, T australis and T tabaci adults in flowers occurred among orchards and between seasons. No factor was conclusively related to thrips numbers but flowers of late-flowering stonefruit varieties tended to hold more thrips than those of early-flowering varieties. Our results indicate that the common thrips species present on stonefruit trees in the Granite Belt are also ones previously shown to transmit PNRSV via infected pollen in the laboratory and that these thrips are concentrated in stonefruit flowers where most stonefruit pollen is deposited. These results contribute to mounting circumstantial evidence that stonefruit flowers may be inoculated with PNRSV via an interaction of thrips with virus-bearing pollen and that this transmission mechanism may be an important cause of new tree infections in the field.

Finite element analysis of pectus carinatum surgical correction via a minimally invasive approach

Pectus carinatum (PC) is a chest deformity caused by a disproportionate growth of the costal cartilages compared to the bony thoracic skeleton, pulling the sternum towards, which leads to its protrusion. There has been a growing interest on using the ‘reversed Nuss’ technique as minimally invasive procedure for PC surgical correction. A corrective bar is introduced between the skin and the thoracic cage and positioned on top of the sternum highest protrusion area for continuous pressure. Then, it is fixed to the ribs and kept implanted for about 2–3 years. The purpose of this work was to (a) assess the stresses distribution on the thoracic cage that arise from the procedure, and (b) investigate the impact of different positioning of the corrective bar along the sternum. The higher stresses were generated on the 4th, 5th and 6th ribs backend, supporting the hypothesis of pectus deformities correction-induced scoliosis. The different bar positioning originated different stresses on the ribs’ backend. The bar position that led to lower stresses generated on the ribs backend was the one that also led to the smallest sternum displacement. However, this may be preferred, as the risk of induced scoliosis is lowered.

Acesso a laboratórios remotos via ambientes imersivos acesso remoto a um multímetro

Recentemente, tem-se assistido à utilização de ambientes imersivos 3D em vários domínios tais como: actividades empresariais, educativas, lúdicas, entre outras devido à expansão do Second Life. A finalidade deste conceito é oferecer aos utilizadores um acesso alternativo a valências existentes no mundo real, a partir de um computador ligado à Internet. Uma aplicação prática pode ser a sua utilização em laboratórios remotos, com a finalidade de controlar remotamente instrumentos de medição, a partir de um ambiente imersivo. Para isso, o mesmo deve permitir a construção de um laboratório virtual e respectivos instrumentos, também virtuais. Este tipo de solução é viável, devido a existirem dispositivos com interfaces de acesso remoto, e ambientes 3D desenvolvidos em linguagens de programação que possuem bibliotecas de código para protocolos de redes de computadores. A finalidade deste trabalho é desenvolver uma metodologia de acesso remoto, a instrumentos de medição em laboratórios de electricidade e electrónica, usando ambientes imersivos 3D. Como caso de estudo, o instrumento utilizado é um multímetro, controlado remotamente a partir de uma reprodução num mundo virtual, construído no ambiente 3D Open Wonderland. Nessa reprodução virtual, numa primeira fase, só serão disponibilizadas para medição, um conjunto limitado das variáveis eléctricas passíveis de medir através do multímetro seleccionado.

eTourism – Mobile Data Interface (Sistema de Apoio On-Line ao Turista em Dispositivos Móveis com Adaptação de Tours Personalizados)

O intuito principal desta Tese é criar um interface de Dados entre uma fonte de informação e fornecimento de Rotas para turistas e disponibilizar essa informação através de um sistema móvel interactivo de navegação e visualização desses mesmos dados. O formato tecnológico será portátil e orientado à mobilidade (PDA) e deverá ser prático, intuitivo e multi-facetado, permitindo boa usabilidade a públicos de várias faixas etárias. Haverá uma componente de IA (Inteligência Artificial), que irá usar a informação fornecida para tomar decisões ponderadas tendo em conta uma diversidade de aspectos. O Sistema a desenvolver deverá ser, assim, capaz de lidar com imponderáveis (alterações de rota, gestão de horários, cancelamento de pontos de visita, novos pontos de visita) e, finalmente, deverá ajudar o turista a gerir o seu tempo entre Pontos de Interesse (POI – Points os Interest). Deverá também permitir seguir ou não um dado percurso pré-definido, havendo possibilidade de cenários de exploração de POIs, sugeridos a partir de sugestões in loco, similares a Locais incluídos no trajecto, que se enquadravam no perfil dos Utilizadores. O âmbito geográfico de teste deste projecto será a zona ribeirinha do porto, por ser um ex-líbris da cidade e, simultaneamente, uma zona com muitos desafios ao nível geográfico (com a inclinação) e ao nível do grande número de Eventos e Locais a visitar.

Monitorização via internet de processos industriais controlados com autómatos programáveis

Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia Mecânica

A comparative analysis of fault injection methods via enhanced on-chip debug infrastructures

On-chip debug (OCD) features are frequently available in modern microprocessors. Their contribution to shorten the time-to-market justifies the industry investment in this area, where a number of competing or complementary proposals are available or under development, e.g. NEXUS, CJTAG, IJTAG. The controllability and observability features provided by OCD infrastructures provide a valuable toolbox that can be used well beyond the debugging arena, improving the return on investment rate by diluting its cost across a wider spectrum of application areas. This paper discusses the use of OCD features for validating fault tolerant architectures, and in particular the efficiency of various fault injection methods provided by enhanced OCD infrastructures. The reference data for our comparative study was captured on a workbench comprising the 32-bit Freescale MPC-565 microprocessor, an iSYSTEM IC3000 debugger (iTracePro version) and the Winidea 2005 debugging package. All enhanced OCD infrastructures were implemented in VHDL and the results were obtained by simulation within the same fault injection environment. The focus of this paper is on the comparative analysis of the experimental results obtained for various OCD configurations and debugging scenarios.