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RESUMO O objetivo do trabalho consistiu em avaliar a influência da sazonalidade, da eventual sobrecarga hidráulica, do porte, do custo e da idade no desempenho de estações convencionais de tratamento de água pela análise de confiabilidade como ferramenta de avaliação. Para tal, empregaram-se dados operacionais do efluente de 20 estações operadas pelo mesmo prestador referentes ao período 2009-2014. As análises estatísticas mostraram que o desempenho, em termos de turbidez do efluente, elevou-se no período de estiagem em relação ao chuvoso e nas unidades de pequeno porte avaliadas. No mesmo contexto, a quase totalidade das estações submetidas à sobrecarga hidráulica apresentou desempenho inferior. A determinação da faixa de turbidez requerida na saída da estação, pela análise de confiabilidade, mostrou-se importante ferramenta de gestão permitindo hierarquizar ações de melhorias nos sistemas. Não se verificou correlação entre o nível de confiabilidade e o custo do tratamento e a idade da estação.

ABSTRACT The objective of this work was to evaluate the influence of seasonality, possible hydraulic overload, size, cost, and age of the station in the performance of conventional water treatment stations based on reliability analysis as an evaluation tool. For this purpose, operational data of the effluent from 20 stations operated by the same provider for the 2009-2014 period were used. Statistical analyses showed that the performance was increased in the dry season compared to the rainy one and in the small units evaluated. In the same scenario, almost all the stations submitted to hydraulic overload exhibit inferior performance. The determination of turbidity range required at the exit of the station, through the reliability analysis, proved to be an important management tool, allowing to hierarchize improvement actions in the systems. In addition, there was no correlation between the level of reliability and the treatment cost and the age of the station.

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ABSTRACT BACKGROUND: Leg length discrepancy (LLD) may play a key role in exercise biomechanics. Although the Podoprint platform has been used in dynamic pressure studies, there are no data regarding the reliability and repeatability of dynamic measurements under simulated LLD conditions. OBJECTIVES: To determine the intra and intersession repeatability and reliability of dynamic parameters of the Podoprint pressure platform under simulated LLD conditions. DESIGN AND SETTING: Observational cross-sectional study at a public university. METHODS: Thirty-seven healthy volunteers participated in this study. LLD was simulated using ethyl vinyl acetate plantar lifts with heights of 5 mm, 10 mm, 15 mm and 20 mm located under the right shoe of each volunteer. The procedure was performed to capture the dynamic parameters of each participant under five different simulated LLD conditions. Stance time, mean pressure and peak pressure measurements were registered in three trials for each foot and each LLD level. Data were collected during two separate testing sessions, in order to establish intrasession and intersession reliability. RESULTS: The intraclass correlation coefficients (ICCs) for intrasession reliability ranged from 0.775 to 0.983 in the first session and from 0.860 to 0.985 in the second session. The ICCs for intersession reliability ranged from 0.909 to 0.990. Bland-Altman plots showed absence of systematic measurement errors. CONCLUSIONS: The results from this study indicate that the Podoprint platform is a reliable system for assessing dynamic parameters under simulated LLD conditions. Future studies should evaluate plantar pressures under LLD conditions, in association with exercise, biomechanics and musculoskeletal disorders.

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The Generalized Renewal Process (GRP) is a probabilistic model for repairable systems that can represent the usual states of a system after a repair: as new, as old, or in a condition between new and old. It is often coupled with the Weibull distribution, widely used in the reliability context. In this paper, we develop novel GRP models based on probability distributions that stem from the Tsallis' non-extensive entropy, namely the q-Exponential and the q-Weibull distributions. The q-Exponential and Weibull distributions can model decreasing, constant or increasing failure intensity functions. However, the power law behavior of the q-Exponential probability density function for specific parameter values is an advantage over the Weibull distribution when adjusting data containing extreme values. The q-Weibull probability distribution, in turn, can also fit data with bathtub-shaped or unimodal failure intensities in addition to the behaviors already mentioned. Therefore, the q-Exponential-GRP is an alternative for the Weibull-GRP model and the q-Weibull-GRP generalizes both. The method of maximum likelihood is used for their parameters' estimation by means of a particle swarm optimization algorithm, and Monte Carlo simulations are performed for the sake of validation. The proposed models and algorithms are applied to examples involving reliability-related data of complex systems and the obtained results suggest GRP plus q-distributions are promising techniques for the analyses of repairable systems.

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El estudio del engagement en el trabajo es cada vez más común en la literatura científica. La estructura factorial del instrumento más utilizado por los investigadores para evaluar el engagement, la Utrecht Work Engagement Scale (UWES), ha mostrado múltiples inconsistencias en diversos países. El objetivo de este trabajo es examinar las propiedades psicométricas de la UWES en una muestra de 2.796 trabajadores en Puerto Rico. Se examinó la estructura factorial de la escala mediante ecuaciones estructurales, con el método de estimación de máxima verosimilitud. Los resultados muestran que el modelo de tres factores posee un mejor ajuste a los datos de la escala, siendo consistente con la concepción del engagement como constructo compuesto por tres dimensiones: vigor, dedicación y absorción. La validez y la fiabilidad de la UWES son adecuadas, por lo que se concluyó que la escala posee las cualidades para ser utilizada en investigaciones en el contexto laboral puertorriqueño.

The study of work engagement is becoming increasingly common in the scientific literature. There are many inconsistencies regarding the factorial structure of the Utrecht Work Engagement Scale (UWES) the most widely used instrument by researchers in different countries. The objective of this study is to examine the psychometric properties of the UWES using a sample of 2,796 employees in Puerto Rico. We examined the psychometric properties of UWES using structural equations with the method of maximum likelihood estimation. The results show that the three-factor model has a better fit, being consistent with the conception of engagement as a construct formed by three dimensions: vigor, dedication, and absorption. The validity and reliability of UWES are appropriate, and we conclude that the scale has the qualities to be used in research in the Puerto Rican labor context.

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This article presents an iterative six-step risk analysis methodology based on hybrid Bayesian networks (BNs). In typical risk analysis, systems are usually modeled as discrete and Boolean variables with constant failure rates via fault trees. Nevertheless, in many cases, it is not possible to perform an efficient analysis using only discrete and Boolean variables. The approach put forward by the proposed methodology makes use of BNs and incorporates recent developments that facilitate the use of continuous variables whose values may have any probability distributions. Thus, this approach makes the methodology particularly useful in cases where the available data for quantification of hazardous events probabilities are scarce or nonexistent, there is dependence among events, or when nonbinary events are involved. The methodology is applied to the risk analysis of a regasification system of liquefied natural gas (LNG) on board an FSRU (floating, storage, and regasification unit). LNG is becoming an important energy source option and the world's capacity to produce LNG is surging. Large reserves of natural gas exist worldwide, particularly in areas where the resources exceed the demand. Thus, this natural gas is liquefied for shipping and the storage and regasification process usually occurs at onshore plants. However, a new option for LNG storage and regasification has been proposed: the FSRU. As very few FSRUs have been put into operation, relevant failure data on FSRU systems are scarce. The results show the usefulness of the proposed methodology for cases where the risk analysis must be performed under considerable uncertainty.

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La evaluación de las competencias específicas tiene el propósito de contribuir al desarrollo de los profesionales de la salud y prepararlos para lograr un alto desempeño en la realización de sus actividades y funciones, estar técnicamente calificados para la investigación y ser capaces de desarrollar habilidades para dar respuesta a los problemas con una consecuente y real sistematización de la experiencia científica. En la presente investigación se midió el nivel de actualización científico-técnica del personal de Enfermería que labora en servicios de Neonatología. Se creó un grupo de expertos para determinar los temas a evaluar, confeccionar la tabla de especificaciones y diseñar el instrumento. Se realizó el análisis de confiabilidad del examen. Se detectaron algunas insuficiencias de conocimientos

The evaluation of the specific competences is aimed at contributing to the development of health professionals and at preparing them to attain a high performance in their activities and functions and to be technically qualified for research and to be able to develop abilities to give an answer to the problems with a consequent and real systematization of the scientific experience. The scientific and technical updating level of the nursing personnel working in the Neonatology services was measured. A group of experts was created to determine the topics to be evaluated, to make the table of specifications and to desing the instrument. The reliability analysis of the test was made. Some knowledge deficiencies were detected.

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