Ventilation and energy efficiency of buildings

O presente artigo sustenta-se numa síntese de conhecimentos sobre ventilação e eficiência energética, num contexto social de maior procura de condições de conforto no interior dos mesmos. Nas últimas décadas tem aumentado a preocupação com o consumo excessivo de energias nos edifícios, o que conduziu ao desenvolvimento e implementação legislação de modo a controlar o problema. A par disso, têm-se desenvolvido diversos tipos de edifícios com elevada eficiência energética, tirando partido do meio em que se inserem e integrando princípios da arquitetura sustentável. Por outro lado, a qualidade de ar interior tem sido uma preocupação constante dos projetistas pois, atualmente, grande parte do dia é passado em espaços fechados e com concentrações de poluentes acima dos recomendados. Estas concentrações devem-se ao aumento da preocupação com a diminuição das infiltrações sem acautelar os valores de renovação de ar adequados. Atualmente, a legislação relativa ao desempenho energético dos edifícios veio evidenciar uma evolução ao nível das exigências regulamentares relativas aos vãos envidraçados, mostrando o forte impacto que estes elementos têm nas condições de conforto interior e por consequência nos consumos energéticos dos mesmos. Os vãos envidraçados são um elemento intermediário nas trocas de energia entre o interior e o exterior, representando também pontos de infiltração não controlada de ar. Torna-se vantajoso a reabilitação dos vãos envidraçados de modo a maximizar a qualidade do ar interior e as condições de conforto, sem aumentar os consumos energéticos.This article is based on a synthesis of knowledge regarding ventilation and energy efficiency, in a social context of greater demand for comfort conditions inside them. In recent decades there has been a growing concern about the excessive consumption of energy in buildings, which has led to the development and implementation of legislation to control the problem. In addition, several types of buildings have been developed with high energy efficiency, taking advantage of the environment in which they integrate and with integrating principles of sustainable architecture. On the other hand, the quality of indoor air has been a constant concern of the project engineer because, today, a large part of the day is spent in enclosed spaces and with concentrations of pollutants above those recommended. These concentrations are due to the rising concern with the reduction of infiltrations without taking in consideration the adequate air renewal values. Currently, the legislation on the energy performance of buildings has shown an evolution in the regulatory requirements for glazed sills, showing the strong impact that these elements have on the interior comfort conditions and consequently on the energy consumptions of themselves. Glazed sills are an intermediate element in energy exchanges between the interior and exterior, also representing points of uncontrolled infiltration of air. It is advantageous to rehabilitate glazed sills in order to maximize indoor air quality and comfort conditions without increasing energy consumption.info:eu-repo/semantics/publishedVersio

Project-based learning in a mechanical engineering course: A new proposal based on student's views

The evolution of learning in higher education is nowadays evident. Several discussions and studies have been performed about new methodologies that can disrupt the way the classes are taught in universities. In this context, Project-Based Learning (PBL) is the most emphasized. In the Mechanical Engineering course at the University of Minho (UM), the Integration Project (IP) courses apply a PBL methodology, being these classes the differentiating element of the Integrated Master in Mechanical Engineering (IMME) compared with other Portuguese universities. However, even if the innovative aspect of this approach is recognized nationally, the opinions between students and Professors, about the structure and organization of this class, are still divided. In that sense, this work presents a new proposal for the IP courses in which the opinion of students and successful models implemented in international universities are considered. This study analyses the best PBL methodologies implemented in Engineering courses and presents a PBL model actually implemented at the IMME. This information is combined with the student's views obtained from a survey conducted at the Department of Mechanical Engineering (DEM), regarding the actual PBL model. Through this study, a new proposal for the IP courses is presented. This proposal intends to provide an effective answer to the necessity of the students, using successful tools and methodologies to improve the teaching and learning process in the IMME course. Through this proposal, it is expected to increase the learning process and motivation of the students making them better prepared for a productive profession.The first author would like to express her gratitude for the support given by the Portuguese Foundation for Science and Technology (FCT) and the MIT Portugal Program. This work has been supported by FCT - Fundacao para a Ciencia e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020 (ALGORITMI Center) and R&D Units Project Scope UIDP/04077/2020 (METRICS Center)

Rocker outsole shoes and margin of stability during walking: a preliminary study

Rocker outsole shoes are commonly prescribed to diabetic patients to redistribute peak plantar pressures at high risk areas such as forefoot thereby decreasing risks of plantar ulceration. However, there are evidences of postural destabilizing effect of the rocker outsole shoes. Patients with diabetes, particularly those suffering from neuropathy, are at a higher risk of falling. Then, beside primary role of rocker outsole in offloading, it is essential to explore the effect of the rocker outsole on postural stability of these patients. The smaller base of support (BOS) of the rocker outsoles due to their specific geometry has been previously mentioned as a threat to postural stability. Margin of stability (MOS) appeared to be an appropriate method for measuring postural stability during walking by considering the dynamicity of BOS in its equation. MOS is defined as the distance between the velocity adjusted position of the centre of mass (COM) and the boundaries of the BOS which constantly changes during walking. Then, this study proposes how we can use MOS concept to investigate the impact of the rocker outsoles on dynamic stability. In this study the kinematic data from a single subject with diabetic neuropathy was used to explain the efficiency of the methodology. Conclusive results are expected after carrying out systematic tests using a statistically representative sample size.This project is funded by Iran University of Medical Sciences (IR.IUMS.REC. 1395.9211503202).info:eu-repo/semantics/publishedVersio

Project, development and test of an artificial multifunctional foot

The main purpose of this project is the development of a multifunctional artificial foot, capable of duplicate a human foot in a laboratory environment, in order to evaluate and simulate footwear’s performance under certain conditions. This foot is used as a laboratory prototype and is multisegmented, in order that each section is controlled independently in terms of heat generation and sweating rate, therefore it is possible to simulate more accurately the real behaviour of a human foot. The device produces thermal insulation values that will help to design footwear with better ability in terms of thermal comfort, replacing human volunteers in thermal comfort perception tests, which are very subjective. The prototype was already tested, and preliminary results indicated that thermal insulation values are within the range of expected values produced by other foot thermal manikins and by human volunteers’ tests. This fact suggests that this lab prototype can be used in future thermal comfort evaluations.This project was supported by FCT (the Portuguese Foundation for Science and Technology) and CTCP (Fo otwear Technology Centre of Portugal) because of its poten tial interest and added value to the footwear industry, which is one of the most profitable business areas in Portugal.info:eu-repo/semantics/publishedVersio

Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

Síntese de um mecanismo simulador de marcha para aplicação em ensaios de calçado

O presente trabalho insere-se no projecto de um sistema de teste de calçado e consiste no desenvolvimento de um mecanismo de quatro barras capaz de executar um trajecto de ida semelhante à trajectória descrita pelo tornozelo, durante a fase de apoio de um ciclo de marcha humano, segundo o plano sagital. A criação deste mecanismo seguiu uma metodologia de “síntese de mecanismos” e consistiu na utilização de modelos matemáticos de análise de mecanismos para encontrar, por substituição directa, um mecanismo capaz de executar uma trajectória aproximada à pretendida. A análise cinemática do mecanismo foi realizada analiticamente, com base nos referidos modelos matemáticos, e numericamente. O cálculo numérico realizou-se num programa de análise cinemática de sistemas multicorpo de Flores et al. (2005) desenvolvido em Compaq® Visual Fortran version 6.5 e no software MSC Working Model® 4D 6.1, após a simulação e modelização do mecanismo neste último. Esta análise permitiu concluir que o mecanismo desenvolvido é capaz de executar continuamente vários ciclos de marcha, completando uma fase de apoio num intervalo de tempo igual ao real, e que a velocidade com que executa a fase de apoio é uma vantagem deste sistema em relação a outros existentes

Development of an artificial multifunctional foot: A project review

The main purpose of this project is the development of a multifunctional artificial foot, capable of duplicate a human foot in a laboratory environment, in order to evaluate and simulate footwear's performance under certain conditions. This foot is used as a laboratory prototype and is multisegmented, in order that each section is controlled independently in terms of heat generation and sweating rate, therefore it is possible to simulate more accurately the real behaviour of a human foot. The device produces thermal insulation values that will help to design footwear with better ability in terms of thermal comfort, replacing human volunteers in thermal comfort perception tests, which are very subjective. The prototype was already tested, and preliminary results indicated that thermal insulation values are within the range of expected values produced by other foot thermal manikins and by human volunteers' tests. This fact suggests that this lab prototype can be used infuture thermal comfort evaluations.(undefined

BioMed2008-38065 THE INFLUENCE OF RENAL BRANCHES ON THE ILIAC ARTERIES BLOOD FLOW

ABSTRACT The characterization of blood flow is important to establish links between the hemodynamics and the occurrence of cardiovascular diseases. This study describes the development of a 3-D computational model able to predict the blood flow along the abdominal aorta, including the renal and iliac branches. Upstream branches in the abdominal aorta lead to more complex flow patterns downstream, intensifying reverse and asymmetric flow patterns. The focus is on the occurrence of reverse flow and the perturbations in blood flow patterns originated by the branches. Results show regions of recirculation in the walls of the abdominal aorta, renal and iliac branches. It is concluded that, the renal branches induces perturbations in blood flow and result in asymmetric velocity profiles