Development of an electrical power quality monitor based on a PC

This paper describes an Electric Power Quality Monitor developed at the University of Minho. The hardware of the Monitor is constituted by four current sensors based on Rogowski effect, four voltage sensors based on Hall effect, a signal conditioning board and a computer. The software of the Monitor consists of several applications, and it is based on LabVIEW. The developed applications allow the equipment to function as a digital scope, analyze harmonic content, detect and record disturbances in the voltage (wave shapes, sags, swells, and interruptions), measure energy, power, unbalances, power factor, register and visualize strip charts, register a great number of data in the hard drive and generate reports. This article also depicts an Electrical Power Quality Monitor Integrated into Active Power Filters developed at the University of Minho.Fundação para a Ciência e a Tecnologia (FCT

Single-phase shunt active filter interfacing renewable energy sources with the power grid

This paper presents a single-phase Shunt Active Filter combined with a Maximum Power Point Tracker (MPPT) connected to a solar panel array. The Shunt Active Filter’s power stage consists of a two-leg IGBT inverter commanded by a Digital Signal Processor (DSP) with control based on the Theory of Instantaneous Reactive Power (p-q Theory). The MPPT is based on a step-up circuit commanded by a DSP with MPPT Algorithm implemented. The output of the MPPT circuit is connected to the DC side of the Shunt Active Filter. The system is capable of compensating power factor and current harmonics, and at the same time, using the same inverter, injecting in the power grid electric energy produced by solar panels, regulated by the MPPT. There will be presented results of the system operating in an electrical installation under different conditions, as well as the hardware configuration and specifications.Fundação para a Ciência e a Tecnologia (FCT

Sistema de monitorização de energia eléctrica

Este artigo descreve o desenvolvimento de um Sistema de Monitorização de Energia Eléctrica de baixo custo baseado num PC (computador pessoal) [1, 2]. O equipamento é constituído por quatro sensores de corrente com bobinas de Rogowski, quatro sensores de tensão baseados no efeito Hall com controlo em malha fechada, uma placa de condicionamento e um PC. O software é baseado em LabView e apresenta várias aplicações desenvolvidas, das quais destacam-se: “Aplicação para Determinação de Problemas de Qualidade de Energia” [1], “Aplicação Osciloscópio e Distorção Harmónica”, “Aplicação Fasores e Grandezas Clássicas”, Aplicação Teoria p-q” e “Aplicação Visualização de Dados e Geração de Relatórios”. A utilização de um PC permite, para além de uma grande flexibilidade do sistema, e de uma interface amigável com o utilizador, também a possibilidade de recorrer a recursos provenientes de ferramentas de Internet, como é o caso do acesso remoto. Este artigo descreve ainda a integração deste sistema de monitorização a Filtros Activos de Potência do tipo Paralelo, também desenvolvidos na Universidade do Minho.Fundação para a Ciência e a Tecnologia (FCT

Electric power quality monitoring results in different facilities

This paper presents results of electric power quality monitoring studies performed in different industries and in universities. The monitoring was made with an Electric Power Quality Monitor developed at the University of Minho. The studies were performed in different installations: textile industries, a pharmaceutical industry, a hospital and two universities. Therefore, the results showed in this paper were obtained in different electrical installations. It is important to emphasize that, the results here presented are not intended to establish profiles for each type of electrical installation. The aim is rather to show several electric power problems that occur in these types of facilities, and also to present the functionalities of the Electric Power Quality Monitor developed at the University of Minho, working out of laboratory, in real electrical installations.Fundação para a Ciência e a Tecnologia (FCT

inTB - a data integration platform for molecular and clinical epidemiological analysis of tuberculosis

This deposit is composed by the main article plus the supplementary materials of the publication.Tuberculosis is currently the second highest cause of death from infectious diseases worldwide. The emergence of multi and extensive drug resistance is threatening to make tuberculosis incurable. There is growing evidence that the genetic diversity of Mycobacterium tuberculosis may have important clinical consequences. Therefore, combining genetic, clinical and socio-demographic data is critical to understand the epidemiology of this infectious disease, and how virulence and other phenotypic traits evolve over time. This requires dedicated bioinformatics platforms, capable of integrating and enabling analyses of this heterogeneous data.Instituto Gulbenkian de Ciência, Programa Nacional de Luta contra a Tuberculose, Instituto Nacional de Saúde Ricardo Jorge, Administração Regional de Saúde de Lisboa e Vale do Tejo

The effects of pre-season and relationships with physical, physiological, body composition, and load markers: a case study comparing starters versus non-starters from an elite female professional soccer team

Background and Objectives: Research on female soccer players that analyzes playing status is scarce and has previously only examined load monitoring, while other markers, such as physical (i.e., strength, power, and agility), physiological (i.e., maximal oxygen uptake), and body composition (i.e., body fat mass, fat-free mass, body water, and phase angle) markers, warrant further investigation. Thus, the study aims were to (a) compare physical, physiological, body composition, and load markers between starters and non-starters; (b) compare measurements pre- and post-training intervention (five weeks); and (c) analyze any relationships between physical, physiological, body composition, and load markers in an elite female soccer team. Materials and Methods: Fourteen first-team players participated in the study (age 23.29 ± 3.19 years, weight 59.14 ± 6.87 kg, height 1.66 ± 0.08 m). Several physical (n = 15), physiological (n = 1), body composition (n = 11), and load markers (n = 14) were collected. In addition, participants were sub-divided into starters (n = 7) and non-starters (n = 7). Results: No differences were revealed between starters and non-starters in any of the examined variables. Moreover, following the training intervention, a significantly lower value was found for total body water/fat-free mass ratio (p = 0.043; ES = 0.582). In addition, there were several correlations detected between load and physical/physiological markers (n = 28); load and body composition markers (n = 6); physical/physiological and body composition markers (n = 34); and physical and physiological markers (n = 42). Conclusions: In conclusion, only a slight tendency of higher load values for starters than non-starters was observed. In addition, no differences in physical, physiological, and body composition markers were found between starters and non-starters, possibly suggesting that five weeks were not enough to improve such variables. Finally, the present results provide novel information assessing the effects of the pre-season in elite female Portuguese soccer players and contribute to a better understanding of the associations between different types of measurements.info:eu-repo/semantics/publishedVersio

Macroinvertebrates associated with bryophyta in a first-order Atlantic Forest stream

This study describes the composition and structure of the benthic community associated with bryophytes in a first-order stream, located in a biological reserve of the Atlantic Forest, during two seasons. During three months of the dry season of 2007 and three months of the rainy season of 2008, samples of bryophytes attached to stones were collected randomly, along a 100 m stream reach. The structure of the community was analyzed through the mean density of individuals, Shannon's diversity index, Pielou's evenness, family richness, dominance index, and the percentage of Ephemeroptera, Plecoptera and Trichoptera (% EPT). Chironomidae larvae were dominant in the two periods of study, followed by Ceratopogonidae in the rainy season, and Naididae in the dry season. The orders EPT contributed 14 families. The results showed that bryophytes constitute suitable habitat which is able to shelter an abundant and diversified benthic fauna in a small extension of the stream. This habitat provides refuge during spates, and thus minimizes downstream transport of the macroinvertebrate fauna.

Measurement of relaxation times in extensional flow of weakly viscoelastic polymer solutions

The characterization of the extensional rheology of polymeric solutions is important in several applications and industrial processes. Filament stretching andcapillary breakup rheometers have been developed to characterize the extensional properties of polymeric solutions,mostly for high-viscosity fluids. However, for low concentration polymer solutions, the measurements are difficultusing available devices, in terms of the minimum viscosity and relaxation times that can be measured accurately.In addition, when the slow retraction method is used, solvent evaporation can affect the measurements for volatilesolvents. In this work, a new setup was tested for filament breakup experiments using the slow retraction method,high-speed imaging techniques, and an immiscible oil bathto reduce solvent evaporation and facilitate particle trackingin the thinning filament. Extensional relaxation times abovearound 100 μs were measured with the device for dilute andsemi-dilute polymer solutions. Particle tracking velocimetrywas also used to measure the velocity in the filament andthe corresponding elongation rate, and to compare with thevalues obtained from the measured exponential decay of thefilament diameter

A fluorescent-labeled microcystin-LR terbium cryptate

Um novo composto fluorescente de microcistina-LR marcado com criptato de térbio foi obtido pela conjugação inicial da microcistina-LR com aminoetanotiol, seguido pela reação com o grupo éster do criptato de térbio. A formação do produto foi acompanhada por cromatografia líquida de alta eficiência (CLAE) em 238 nm e 310 nm. A presença de microcistina-LR na molécula marcada foi confirmada através de ensaio com enzima ligada a imunoabsorvente (ELISA) e por reação protéica com ácido bicincônico. O espectro de luminescência do criptato e da molécula conjugada também foram confirmados.A new fluorescent labeled compound of microcystin-LR with terbium cryptate was obtained by initial conjugation of microcystins-LR with aminoethanethiol followed by the reaction with the ester group of terbium cryptate. The product formation was followed by high performance liquid chromatography (HPLC) at 238 nm and 310 nm. The presence of microcystin-LR in the labeled molecule was confirmed by enzyme linked immunosorbent assay ELISA and by protein reaction with bicinhonic acid. Luminescence spectra of cryptate and the conjugated molecule were carried through as well