Inspeção, Diagnóstico e Reparação de Estruturas de Betão Armado

O mercado da reabilitação de estruturas em Portugal está em voga, sendo um nicho de mercado com evolução galopante nos últimos anos fruto da consciencialização das entidades responsáveis, assim como das necessidades de intervir no parque edificado cada vez mais degradado, resultando num estímulo para o mercado da construção face ao seu estado atual. As causas associadas à degradação prematura dos materiais estruturais resultam de erros de conceção e execução, assim como do facto de muitas estruturas de betão armado do parque habitacional edificado nas décadas de 60 e 70, estarem a atingir o fim do seu período de vida útil. Na avaliação do estado de degradação de estruturas de betão armado aconselha-se a utilização de ensaios não destrutivos, uma vez que permitem efetuar um diagnóstico com resultados positivos salvaguardando a integridade da estrutura. A norma EN 1504“Produtos e Sistemas para a proteção e reparação de estruturas de betão” estipula os procedimentos de execução, as características dos materiais mais adequados a cada tipo de projeto, assim como a divisão do seu encadeamento em 5 fases. O caso prático apresentado é um edifício de prestação de serviços municipais, tendo sido aplicado com o maior rigor possível as fases de inspeção, diagnóstico, deliberação e reparação. Foi efetuada uma fase de diagnóstico, de carácter visual assim como de caracterização física dos elementos estruturais em betão armado através de ensaios “in situ”. A estrutura avaliada apresenta debilidades e um estado de degradação acelerado, pelo que urge uma intervenção de reparação por forma a repor a estrutura com as características da sua conceção, salvaguardando a segurança das pessoas e bens.

Optimização do processo de fabrico de componentes para a indústria automóvel

A qualidade é um factor-chave na indústria automóvel. Todos os fornecedores de componentes para a indústria automóvel estão sujeitos a qualificações e auditorias sistemáticas, com vista a melhorar os processos e verificar a sua rastreabilidade. Quando os processos assentam essencialmente em mão-de-obra intensiva, torna-se muito mais difícil atingir a ambicionada meta dos zero-defeitos, e a garantia da qualidade pode ficar comprometida, sendo necessário instalar procedimentos de controlo mais apurados. No entanto, se o processo ou processos forem convenientemente definidos, e se optar por capital intensivo em detrimento da mão-de-obra intensiva, a garantia da qualidade pode ser uma realidade, podendo ser fortemente minimizadas as operações de controlo da qualidade. Este trabalho teve por base a necessidade de reduzir fortemente, ou eliminar mesmo, o aparecimento de defeitos de montagem num sistema designado por remachado. Após cuidada análise do processo instalado, já parcialmente automatizado, mas ainda fortemente dependente de mão-de-obra, procedeu-se ao projecto de um equipamento capaz de reproduzir o mesmo efeito, mas que acomodasse alguns possíveis defeitos oriundos dos fornecedores dos componentes que são inseridos neste conjunto, colocados a montante na cadeia de fornecimento do produto. O equipamento resultante deste trabalho permitiu baixar o tempo de ciclo, acomodar a variabilidade dimensional detectada nos componentes que constituem o conjunto e reduzir drasticamente o número de não-conformidades.

Cultural Intelligence Scale: Validation in a Multicultural Setting of Erasmus Mundus Students and Alumni

Purpose: This work aims at further developing and testing the psychometric properties of the Cultural Intelligence Scale (Ang & Van Dyne, 2006) in an Erasmus Mundus Students and Alumni Population, including reliability. Design Methodology: The study included 626 participants from 109 different countries that emcompasses 6 continents. Exploratory and Confirmatory Factor Analysis procedures were carried out in order to test the scale in a multicultural scale of Erasmus Mundus Students. Reliability was assessed using Cronbach Alpha. Results: The scale presents excellent psychometric properties with alpha values that range from .84 to .90. Exploratory and Confirmatory Factor Analyses demonstrated that the original model of the scale presents an exceptionally good fit. Limitations: The present study was conducted using a convenience sample and online questionnaires that limit its conclusions when we consider the globality of the Erasmus Mundus Students. Research/Practical Implications: This study presents evidence that Ang and Van Dyne’s scale is an adequate measure instrument to assess intercultural intelligence in a multicultural setting of students and alumni. Originality/Value: Multicultural samples and studies are becoming more and more present and relevant; the study of intercultural competences and habilities is becoming increasingly important, and in this task, solid psychometric instruments are of paramount importance. This study presents evidence that Ang and Van Dyne’s (2006) scale is a fairly recent and parsimonious instrument with excellent psychometric properties properties.

Análise de Integridade Estrutural de uma Flare Industrial

Para garantir que um equipamento opere com segurança e fiabilidade durante o seu ciclo de vida, desde a sua instalação ao desmantelamento, devem ser realizadas inspeções e/ou monitorizações que, dependendo dos dados recolhidos, podem implicar avaliações Fitness- For-Service (FFS) que definirão a necessidade de reparação ou alteração do equipamento ou das condições processuais. A combinação de inspeção ou monitorização com os melhores procedimentos e técnicas de avaliação atuais fazem sobressair insuficiências dos procedimentos mais antigos. Usando métodos mais avançados de avaliação, validados e suportados através de uma vasta experiência de campo, pode-se agora avaliar defeitos nos ativos (equipamentos) e determinar a adequação ao serviço com uma análise FFS. As análises FFS tornaram-se cada vez mais aceites em toda a indústria ao longo dos últimos anos. A norma API 579 - 1/ASME FFS-1: 2007 fornece diretrizes para avaliar os tipos de danos que afetam os equipamentos processuais e a norma API RP 571: 2011 descreve os mecanismos de degradação que afetam os equipamentos nas petroquímicas e refinarias, que incluem os danos por corrosão, desalinhamentos, deformações plásticas, laminações, fissuras, entre outros. Este trabalho consiste na análise de Integridade Estrutural de uma Flare Industrial que surgiu da necessidade real de análise do equipamento no âmbito da atividade profissional do candidato. O estudo realizado a nível profissional é de grande abrangência, incluindo a inspeção do equipamento, identificação da falha ou dano, recolha e registo de dados, definição de estratégia de atuação e seleção de técnicas de avaliação da condição para posterior alteração, reparação ou desmantelamento. Na presente dissertação de mestrado em Engenharia Mecânica, Ramo Construções Mecânicas, pretende-se efetuar o estudo aprofundado de uma das etapas de projeto, nomeadamente estudar a causa, avaliar a falha e implicações estruturais ou processuais devido à degradação interior do riser de uma flare, com base numa análise FFS, assumindo a operabilidade em segurança e garantindo resolutas condições de funcionamento. A presente análise FFS tem como finalidade validar ou não a integridade atual (avaliação técnica quantitativa) de modo a conhecer se o item em questão é seguro e confiável para continuar a operar em condições específicas durante um período de tempo determinado, tendo em consideração as condições verificadas no ato de inspeção e especificações de projeto, segundo os itens de verificação de segurança estabelecidos na norma EN 1990:2002/A1:2005/AC:2010 e com base na norma API 579-1/ASME FFS-1: 2007. No âmbito do presente trabalho foram realizadas as seguintes tarefas: - Identificar e analisar os mecanismos de degradação com base na norma API RP 571: 2011, face às condições processuais e geométricas que o equipamento em análise está sujeito de modo a perceber a evolução da degradação estrutural e quais as implicações na sua longevidade. - Avaliar e propor soluções de reparação e ou alterações processuais e ou geométricas do equipamento em análise de modo a permitir a continuidade em funcionamento sem afetar as condições de segurança e por conseguinte minimizar ou evitar o elevado custo económico associado a um novo equipamento e tempo de paragem processual. - Assumir limites estruturais face às condições processuais e ações externas ou adjacentes. - Garantir a segurança e qualidade da vida humana ou meio que o rodeia, do equipamento, das instalações, das infraestruturas envolventes e evitar o colapso económico, quer por motivos processuais, quer indeminizações ou agravamento do prémio do seguro. Verificou-se que os resultados serão a base para as alterações inerentes, tais como reforço estrutural, alteração da geometria do defletor, ajuste no tensionamento dos cabos e controlo da espessura mínima, de modo a alargar o período de vida útil da flare com segurança.

Study of behavioural and neural bases of visuo-spatial working memory with an fMRI paradigm based on an n-back task

The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language-free adaptation of a 2-back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the task's capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM-based random effects procedures and t-tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self-corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non-clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block-design paradigms.

The influence of task design on upper limb muscles fatigue during low-load repetitive work: A systematic review

Ergonomic interventions such as increased scheduled breaks or job rotation have been proposed to reduce upper limb muscle fatigue in repetitive low-load work. This review was performed to summarize and analyze the studies investigating the effect of job rotation and work-rest schemes, as well as, work pace, cycle time and duty cycle, on upper limb muscle fatigue. The effects of these work organization factors on subjective fatigue or discomfort were also analyzed. This review was based on relevant articles published in PubMed, Scopus and Web of Science. The studies included in this review were performed in humans and assessed muscle fatigue in upper limbs. 14 articles were included in the systematic review. Few studies were performed in a real work environment and the most common methods used to assess muscle fatigue were surface electromyography (EMG). No consistent results were found related to the effects of job rotation on muscle activity and subjective measurements of fatigue. Rest breaks had some positive effects, particularly in perceived discomfort. The increase in work pace reveals a higher muscular load in specific muscles. The duration of experiments and characteristics of participants appear to be the factors that most have influenced the results. Future research should be focused on the improvement of the experimental protocols and instrumentation, in order to the outcomes represent adequately the actual working conditions. Relevance to industry: Introducing more physical workload variation in low-load repetitive work is considered an effective ergonomic intervention against muscle fatigue and musculoskeletal disorders in industry. Results will be useful to identify the need of future research, which will eventually lead to the adoption of best industrial work practices according to the workers capabilities.

Design and Development of a Solar Dryer for Microalgae Retrieval - An EPS@ISEP 2013 Spring Project

Currently excessive fossil fuel consumption has become a serious problem. People are searching for new solutions of energy production and there are several options to obtain alternative sources of energy without further devastating the already destroyed environment. One of these solutions is growing microalgae, from which biodiesel can be obtained. The microalgae production is a growing business because of its many useful compounds. In order to collect these compounds microalgae must first be harvested and then dried. Nowadays the solutions used for drying use too much energy and therefore are too expensive and not sustainable. The goal of this project, one of the possible choices during the EPS@ISEP 2013 Spring, was to develop a solar microalgae dryer. The multinational team involved in its development was composed of five students, from distinct countries and fields of study, and was the responsible for designing a solar microalgae dryer prototype for the microalgae laboratory of the chemical engineering department at ISEP, suitable for future tests and incorporating control process (in order not to destroy the microalgae during the drying process). The solar microalgae dryer was built to work as a distiller that gets rid of the excess water from the microalgae suspension. This paper presents a possible solution for this problem, the steps to create the device to harvest the microalgae by drying them with the use of solar energy (also used as an energy source for the solar dryer control system), the technologies used to build the solar microalgae dryer, and the benefits it presents compared to current solutions. It also presents the device from the ethical and sustainable viewpoint. Such alternative to already existing methods is competitive as far as energy usage is concerned.

Design and Implementation of a Biologically Inspired Flying Robot - An EPS@ISEP 2014 Spring Project

The goal of this EPS@ISEP project proposed in the Spring of 2014 was to develop a flapping wing flying robot. The project was embraced by a multinational team composed of four students from different countries and fields of study. The team designed and implemented a robot inspired by a biplane design, constructed from lightweight materials and battery powered. The prototype, called MyBird, was built with a 250 € budget, reuse existing materials as well as low cost solutions. Although the team's initial idea was to build a light radio controlled robot, time limitations along with setbacks involving the required electrical components led to a light but not radio controlled prototype. The team, from the experience gathered, made a number of future improvement suggestions, namely, the addition of radio control and a camera and the adoption of articulated monoplane design instead of the current biplane design for the wings.

Design and Implementation of a Biologically Inspired Swimming Robot - An EPS@ISEP 2014 Spring Project

This paper presents the development of a fish-like robot called Bro-Fish. Bro-Fish aims to be an educational toy dedicated to teaching mechanics, programming and the physics of floating objects to youngsters. The underlying intention is to awaken the interest of children for technology, especially biomimetic (biologically inspired) approaches, in order to promote sustainability and raise the level of ecological awareness. The main focus of this project was to create a robot with carangiform locomotion and controllable swimming, providing the opportunity to customize parts and experiment with the physics of floating objects. Therefore, the locomotion principles of fishes and mechanisms developed in related projects were analysed. Inspired by this background knowledge, a prototype was designed and implemented. The main achievement is the new tail mechanism that propels the robot. The tail resembles the undulation motion of fish bodies and is actuated in an innovative way, triggered by an elegant movement of a rotating helicoidal. First experimental tests revealed the potential of the proposed methodology to effectively generate forward propulsion.

Logic-based schedulability analysis for compositional hard real-time embedded systems

Over the past decades several approaches for schedulability analysis have been proposed for both uni-processor and multi-processor real-time systems. Although different techniques are employed, very little has been put forward in using formal specifications, with the consequent possibility for mis-interpretations or ambiguities in the problem statement. Using a logic based approach to schedulability analysis in the design of hard real-time systems eases the synthesis of correct-by-construction procedures for both static and dynamic verification processes. In this paper we propose a novel approach to schedulability analysis based on a timed temporal logic with time durations. Our approach subsumes classical methods for uni-processor scheduling analysis over compositional resource models by providing the developer with counter-examples, and by ruling out schedules that cause unsafe violations on the system. We also provide an example showing the effectiveness of our proposal.

Optimizing potentiometric ionophore and electrode design for environmental on-site control of antibiotic drugs: Application to sulfamethoxazole

Potentiometric sensors are typically unable to carry out on-site monitoring of environmental drug contaminants because of their high limits of detection (LODs). Designing a novel ligand material for the target analyte and managing the composition of the internal reference solution have been the strategies employed here to produce for the first time a potentiometric-based direct reading method for an environmental drug contaminant. This concept has been applied to sulfamethoxazole (SMX), one of the many antibiotics used in aquaculture practices that may occur in environmental waters. The novel ligand has been produced by imprinting SMX on the surface of graphitic carbon nanostructures (CN) < 500 nm. The imprinted carbon nanostructures (ICN) were dispersed in plasticizer and entrapped in a PVC matrix that included (or not) a small amount of a lipophilic additive. The membrane composition was optimized on solid-contact electrodes, allowing near-Nernstian responses down to 5.2 μg/mL and detecting 1.6 μg/mL. The membranes offered good selectivity against most of the ionic compounds in environmental water. The best membrane cocktail was applied on the smaller end of a 1000 μL micropipette tip made of polypropylene. The tip was then filled with inner reference solution containing SMX and chlorate (as interfering compound). The corresponding concentrations were studied for 1 × 10−5 to 1 × 10−10 and 1 × 10−3 to 1 × 10−8 mol/L. The best condition allowed the detection of 5.92 ng/L (or 2.3 × 10−8 mol/L) SMX for a sub-Nernstian slope of −40.3 mV/decade from 5.0 × 10−8 to 2.4 × 10−5 mol/L.

Rapid automated method for on-site determination of sulfadiazine in fish farming: a stainless steel veterinary syringe coated with a selective membrane of PVC serving as a potentiometric detector in a flow-injection-analysis system

Sulfadiazine is an antibiotic of the sulfonamide group and is used as a veterinary drug in fish farming. Monitoring it in the tanks is fundamental to control the applied doses and avoid environmental dissemination. Pursuing this goal, we included a novel potentiometric design in a flow-injection assembly. The electrode body was a stainless steel needle veterinary syringe of 0.8-mm inner diameter. A selective membrane of PVC acted as a sensory surface. Its composition, the length of the electrode, and other flow variables were optimized. The best performance was obtained for sensors of 1.5-cm length and a membrane composition of 33% PVC, 66% onitrophenyloctyl ether, 1% ion exchanger, and a small amount of a cationic additive. It exhibited Nernstian slopes of 61.0 mV decade-1 down to 1.0×10-5 mol L-1, with a limit of detection of 3.1×10-6 mol L-1 in flowing media. All necessary pH/ionic strength adjustments were performed online by merging the sample plug with a buffer carrier of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, pH 4.9. The sensor exhibited the advantages of a fast response time (less than 15 s), long operational lifetime (60 days), and good selectivity for chloride, nitrite, acetate, tartrate, citrate, and ascorbate. The flow setup was successfully applied to the analysis of aquaculture waters. The analytical results were validated against those obtained with liquid chromatography–tandem mass spectrometry procedures. The sampling rate was about 84 samples per hour and recoveries ranged from 95.9 to 106.9%.

Smart Plastic Antibody Material for Hemoglobin Tailored by Silica Surface Imprinting and with Charged Binding Sites: Its use as Ionophore in Potentiometric Transduction

JORNADAS DE ELECTROQUÍMICA E INOVAÇÃO 2013

Efeito de um programa de autorregulação na promoção da autonomia de um aluno com Perturbação do Espetro do Autismo no 1º ano do 1º ciclo do ensino básico

Objetivo: Este estudo avaliou os efeitos da implementação de um programa de autorregulação no aumento da autonomia de um aluno com Perturbação do Espetro do Autismo, em contexto de sala de aula, no segmento letivo de Português. Método: A metodologia adotada foi quantitativa e experimental, num desenho de investigação de sujeito único, dividido em três fases de investigação: linha de base, início do programa de intervenção e um mês depois. Os registos dos vídeos, e a construção e implementação do programa de intervenção em conjunto com a professora, tiveram como base os princípios e procedimentos da Análise Comportamental Aplica. Resultados / Discussão: Após a implementação do programa de intervenção observou-se um acentuado aumento do envolvimento do aluno e das suas respostas às instruções académicas da professora, essencialmente ao nível das instruções de grupo que, na linha de base, apresentavam valores baixos. A eficácia da intervenção reforça a importância de se capacitar professores na aplicação de técnicas comportamentais dado que, neste estudo e à semelhança de outros, a professora aprendeu rapidamente a implementar práticas que facilmente se ajustam à sala de aula, levando à melhoria sistemática do comportamento do aluno com PEA numa sala de aula inclusiva.

ROAZ and ROAZ II Autonomous Surface Vehicle Design and Implementation

International Lifesaving Congress 2007, La Coruna, Spain, December, 2007