H-NAMe: specifying, implementing and testing a hidden-node avoidance mechanism for wireless sensor networks

The hidden-node problem has been shown to be a major source of Quality-of-Service (QoS) degradation in Wireless Sensor Networks (WSNs) due to factors such as the limited communication range of sensor nodes, link asymmetry and the characteristics of the physical environment. In wireless contention-based Medium Access Control protocols, if two nodes that are not visible to each other transmit to a third node that is visible to the formers, there will be a collision – usually called hidden-node or blind collision. This problem greatly affects network throughput, energy-efficiency and message transfer delays, which might be particularly dramatic in large-scale WSNs. This technical report tackles the hidden-node problem in WSNs and proposes HNAMe, a simple yet efficient distributed mechanism to overcome it. H-NAMe relies on a grouping strategy that splits each cluster of a WSN into disjoint groups of non-hidden nodes and then scales to multiple clusters via a cluster grouping strategy that guarantees no transmission interference between overlapping clusters. We also show that the H-NAMe mechanism can be easily applied to the IEEE 802.15.4/ZigBee protocols with only minor add-ons and ensuring backward compatibility with the standard specifications. We demonstrate the feasibility of H-NAMe via an experimental test-bed, showing that it increases network throughput and transmission success probability up to twice the values obtained without H-NAMe. We believe that the results in this technical report will be quite useful in efficiently enabling IEEE 802.15.4/ZigBee as a WSN protocol.

Relatório de estágio. Terapia manual ortopédica

Objectivo: Descrever a intervenção em fisioterapia aplicada num paciente com o diagnóstico de entorse da Tíbio-társica de grau III. Participantes e Métodos: Paciente que em 1 de Dezembro de 2009 na sequência de uma disputa de bola, sofreu uma entorse da tíbio-társica. Iniciou fisioterapia a 4 de Janeiro de 2010, tendo sido utilizadas para o tratamento técnicas de Mulligan, nomeadamente MWM, mobilização articular, reforço muscular e treino proprioceptivo. O tratamento foi realizado diariamente durante 6 semanas. Resultados: Após a aplicação das técnicas de Mulligan MWM na 1ªsemana, o perónio encontra-se devidamente reposicionado, no entanto o calcâneo ainda se encontra posteriorizado. No fim da 2ªsemana, a amplitude articular aumentou significativamente, aproximando-se dos valores do membro contralateral, verificouse um ganho de força muscular progressivo. Na 3ª e 4ª semana progrediu-se o tratamento em termos de fortalecimento muscular e treino proprioceptivo. Na 5ª semana apresentava amplitudes de movimento de 17º de dorsiflexão, 43º de flexãoplantar, 15º de eversão e 18º de inversão. Relativamente à força, o músculo tibial anterior apresentava um grau 5 de força, longo e curto peronial e flexores plantares grau 4+. No fim de 6 semanas, terminada a sua recuperação encontrava-se sem qualquer limitação funcional, igual força muscular bilateral e proprioceptividade normal. Conclusão: Foi salientado o processo de raciocínio clínico desenvolvido pelo fisioterapeuta ao longo das 6 semanas de intervenção: a recolha e interpretação dos dados da história, levantamento das primeiras hipóteses, testes dessas hipóteses no exame objectivo, estabelecimento de um diagnóstico funcional e construção e implementação de um plano de intervenção com a colaboração do utente que permitiram uma recuperação funcional que foi de encontro aos objectivos traçados.

Intelligent supervisory control system for home devices using a cyber physical approach

Although we have many electric devices at home, there are just few systems to evaluate, monitor and control them. Sometimes users go out and leave their electric devices turned on what can cause energy wasting and dangerous situations. Therefore most of the users may want to know the using states of their electrical appliances through their mobile devices in a pervasive way. In this paper, we propose an Intelligent Supervisory Control System to evaluate, monitor and control the use of electric devices in home, from outside. Because of the transferring data to evaluate, monitor and control user's location and state of home (ex. nobody at home) may be opened to attacks leading to dangerous situations. In our model we include a location privacy module and encryption module to provide security to user location and data. Intelligent Supervising Control System gives to the user the ability to manage electricity loads by means of a multi-agent system involving evaluation, monitoring, control and energy resource agents.

Cyber-physical intelligence in the context of power systems

Cyber-Physical Intelligence is a new concept integrating Cyber-Physical Systems and Intelligent Systems. The paradigm is centered in incorporating intelligent behavior in cyber-physical systems, until now too oriented to the operational technological aspects. In this paper we will describe the use of Cyber-Physical Intelligence in the context of Power Systems, namely in the use of Intelligent SCADA (Supervisory Control and Data Acquisition) systems at different levels of the Power System, from the Power Generation, Transmission, and Distribution Control Centers till the customers houses.

Optimal intelligent supervisory control system in cyber-physical intelligence

This paper studies Optimal Intelligent Supervisory Control System (OISCS) model for the design of control systems which can work in the presence of cyber-physical elements with privacy protection. The development of such architecture has the possibility of providing new ways of integrated control into systems where large amounts of fast computation are not easily available, either due to limitations on power, physical size or choice of computing elements.

Distributed energy resources management with cyber-physical SCADA in the context of future smart grids

In the energy management of a small power system, the scheduling of the generation units is a crucial problem for which adequate methodologies can maximize the performance of the energy supply. This paper proposes an innovative methodology for distributed energy resources management. The optimal operation of distributed generation, demand response and storage resources is formulated as a mixed-integer linear programming model (MILP) and solved by a deterministic optimization technique CPLEX-based implemented in General Algebraic Modeling Systems (GAMS). The paper deals with a vision for the grids of the future, focusing on conceptual and operational aspects of electrical grids characterized by an intensive penetration of DG, in the scope of competitive environments and using artificial intelligence methodologies to attain the envisaged goals. These concepts are implemented in a computational framework which includes both grid and market simulation.

Relatório de estágio: intervenção em fisioterapia na sindrome da cirurgia lombar falhada

Introdução: A síndrome da cirurgia lombar falhada (SCLF) caracteriza-se pela persistência ou recidiva da dor ou aparecimento de novos sintomas após discectomia, descompressão de canal estreito ou artrodese lombares. Objectivos: O objectivo deste estudo foi descrever a abordagem em fisioterapia de um caso com Síndrome da Cirurgia Lombar Falhada e avaliar os seus efeitos na funcionalidade e sintomatologia dolorosa neste indivíduo. Metodologia: A amostra foi constituída por um sujeito com 41 anos, trabalhador da construção civil, apresentando dor lombar com irradiação para o membro inferior, após ter sido submetido a discectomia lombar e artrodese, que realizou sessões de fisioterapia convencional antes e depois da cirurgia, e que apresentava sinais compatíveis com compressão radicular. A intensidade da dor foi medida através da escala visual analógica (EVA), as amplitudes com o goniómetro universal, a funcionalidade foi avaliada utilizando o Questionário de Incapacidade Roland-Morris (RMDQ), o estado psicológico foi avaliado através da “Escala de Desânimo Associado à Dor” e do “Inventário de Convicções e Percepções Relacionadas com a Dor”. Resultados: A dor era inicialmente em média de 5,5/10 EVA, sendo de 3,4/10 EVA no final do tratamento. Quanto à funcionalidade (RMDQ) esta variou de 14/24 no início para 17/24 no final. De uma forma geral, após a aplicação de técnicas para diminuir a tensão do piriforme, técnicas neuurodinâmicas e um programa de exercícios para melhoria do controlo motor, o paciente apresentou alívio das queixas de dor na nádega esquerda e anca, aumento da amplitude de rotação medial da coxo-femoral, ausência das parestesias na face plantar do pé esquerdo e melhoria das queixas de dor na face anterior e lateral da coxa. Verificamos que houve diminuição dos índices de dor e melhorias dos níveis de funcionalidade. Conclusão: Neste estudo de caso, foi salientado o processo de raciocínio clínico desenvolvido pelo fisioterapeuta: a interpretação dos dados da história e levantamento das primeiras hipóteses e a realização dos testes no exame objectivo, permitiram estabelecer um diagnóstico funcional e elaborar um plano de intervenção através do qual o utente recuperou parcialmente a sua funcionalidade e diminuiu os seus índices de dor.

Structural, physical, and chemical modifications induced by microwave heating on native agar-like galactans

Native agars from Gracilaria vermiculophylla produced in sustainable aquaculture systems (IMTA) were extracted under conventional (TWE) and microwave (MAE) heating. The optimal extracts from both processes were compared in terms of their properties. The agars’ structure was further investigated through Fourier transform infrared and NMR spectroscopy. Both samples showed a regular structure with an identical backbone, β-D-galactose (G) and 3,6-anhydro-α-L-galactose (LA) units; a considerable degree of methylation was found at C6 of the G units and, to a lesser extent, at C2 of the LA residues. The methylation degree in the G units was lower for MAEopt agar; the sulfate content was also reduced. MAE led to higher agar recoveries with drastic extraction time and solvent volume reductions. Two times lower values of [η] and Mv obtained for the MAEopt sample indicate substantial depolymerization of the polysaccharide backbone; this was reflected in its gelling properties; yet it was clearly appropriate for commercial application in soft-texture food products.

Concepção e instalação de tabelas multifunções para recintos desportivos cobertos

Mestrado em Engenharia Electrotécnica – Sistemas Eléctricos de Energia

Reconfiguração das colunas de separação de xilenos

Mestrado em Engenharia Química. Ramo optimização energética na indústria química

Produção de biodiesel via catálise heterogénea básica

Mestrado em Engenharia Química. Ramo Tecnologias de Protecção Ambiental.

Deterioração e reabilitação de estruturas de betão armado

Apesar da enorme evolução tecnológica, os prazos na construção são cada vez mais reduzidos e os custos mais controlados, verificando-se uma despreocupação no que diz respeito a aspetos como a qualidade e durabilidade da construção das estruturas. Desperta assim nos técnicos, donos-de-obra, entidades executantes e projetistas a necessidade de avaliar o estado de conservação das estruturas de betão armado. Esta dissertação tem como objetivo principal abordar as anomalias e os mecanismos de deterioração mais correntes, os métodos de ensaio destrutivos ou parcialmente destrutivos mais utilizados e adequados, e abordar algumas das técnicas de reparação e reforço das estruturas de betão armado. Os principais danos apresentados nas estruturas são devidos a agentes físicos, mecânicos, biológicos e químicos. Podem ser devidos a causas diretas (acidentais ou naturais), que acarretam uma ação concreta sobre os elementos estruturais, e causas indiretas (humanas), diretamente ligadas com erros de projeto. É primordial fazer-se o levantamento de todas as anomalias existentes para se recorrer a um método de inspeção e ensaio. Consoante a necessidade de informação e estado da estrutura são selecionados os ensaios a realizar, podendo ser realizados “in situ” ou em laboratório. As técnicas de reparação e reforço são vistas como métodos para melhorar as condições da estrutura ao nível da segurança, desempenho, habitabilidade e durabilidade, prevenindo a evolução dos mecanismos de deterioração.

Food consumption, physical activity and socio-economic status related to BMI, waist circumference and waist-to-height ratio in adolescents

Objective: To examine the association between obesity and food group intakes, physical activity and socio-economic status in adolescents. Design: A cross-sectional study was carried out in 2008. Cole’s cut-off points were used to categorize BMI. Abdominal obesity was defined by a waist circumference at or above the 90th percentile, as well as a waist-to-height ratio at or above 0?500. Diet was evaluated using an FFQ, and the food group consumption was categorized using sex-specific tertiles of each food group amount. Physical activity was assessed via a self-report questionnaire. Socio-economic status was assessed referring to parental education and employment status. Data were analysed separately for girls and boys and the associations among food consumption, physical activity, socio-economic status and BMI, waist circumference and waist-to-height ratio were evaluated using logistic regression analysis, adjusting the results for potential confounders. Setting: Public schools in the Azorean Archipelago, Portugal. Subjects: Adolescents (n 1209) aged 15–18 years. Results: After adjustment, in boys, higher intake of ready-to-eat cereals was a negative predictor while vegetables were a positive predictor of overweight/ obesity and abdominal obesity. Active boys had lower odds of abdominal obesity compared with inactive boys. Boys whose mother showed a low education level had higher odds of abdominal obesity compared with boys whose mother presented a high education level. Concerning girls, higher intake of sweets and pastries was a negative predictor of overweight/obesity and abdominal obesity. Girls in tertile 2 of milk intake had lower odds of abdominal obesity than those in tertile 1. Girls whose father had no relationship with employment displayed higher odds of abdominal obesity compared with girls whose father had high employment status. Conclusions: We have found that different measures of obesity have distinct associations with food group intakes, physical activity and socio-economic status.

Relationship of milk intake and physical activity to abdominal obesity among adolescents

Background: Diet and physical activity (PA) are recognized as important factors to prevent abdominal obesity (AO), which is strongly associated with chronic diseases. Some studies have reported an inverse association between milk consumption and AO. Objective: This study examined the association between milk intake, PA and AO in adolescents. Methods: A cross-sectional study was conducted with 1209 adolescents, aged 15–18 from the Azorean Archipelago, Portugal in 2008. AO was defined by a waist circumference at or above the 90th percentile. Adolescent food intake was measured using a semi-quantitative food frequency questionnaire, and milk intake was categorized as ‘low milk intake’ (<2 servings per day) or ‘high milk intake’ ( 2 servings per day). PA was assessed via a self-report questionnaire, and participants were divided into active (>10 points) and low-active groups ( 10 points) on the basis of their reported PA. They were then divided into four smaller groups, according to milk intake and PA: (i) low milk intake/low active; (ii) low milk intake/active; (iii) high milk intake/low active and (iv) high milk intake/active. The association between milk intake, PA and AO was evaluated using logistic regression analysis, and the results were adjusted for demographic, body mass index, pubertal stage and dietary confounders. Results: In this study, the majority of adolescents consumed semi-skimmed or skimmed milk (92.3%). The group of adolescents with high level of milk intake and active had a lower proportion of AO than did other groups (low milk intake/low active: 34.2%; low milk intake/active: 26.9%; high milk intake/low active: 25.7%; high milk intake/active: 21.9%, P = 0.008). After adjusting for confounders, low-active and active adolescents with high levels of milk intake were less likely to have AO, compared with low-active adolescents with low milk intake (high milk intake/low active, odds ratio [OR] = 0.412, 95% confidence intervals [CI]: 0.201– 0.845; high milk intake/active adolescents, OR = 0.445, 95% CI: 0.235–0.845).Conclusion: High milk intake seems to have a protective effect on AO, regardless of PA level

Mismatch negativity in childhood temporal lobe epilepsy: a proposed paradigm for testing central auditory processing

Background: Temporal lobe epilepsy (TLE) is a neurological disorder that directly affects cortical areas responsible for auditory processing. The resulting abnormalities can be assessed using event-related potentials (ERP), which have high temporal resolution. However, little is known about TLE in terms of dysfunction of early sensory memory encoding or possible correlations between EEGs, linguistic deficits, and seizures. Mismatch negativity (MMN) is an ERP component – elicited by introducing a deviant stimulus while the subject is attending to a repetitive behavioural task – which reflects pre-attentive sensory memory function and reflects neuronal auditory discrimination and perceptional accuracy. Hypothesis: We propose an MMN protocol for future clinical application and research based on the hypothesis that children with TLE may have abnormal MMN for speech and non-speech stimuli. The MMN can be elicited with a passive auditory oddball paradigm, and the abnormalities might be associated with the location and frequency of epileptic seizures. Significance: The suggested protocol might contribute to a better understanding of the neuropsychophysiological basis of MMN. We suggest that in TLE central sound representation may be decreased for speech and non-speech stimuli. Discussion: MMN arises from a difference to speech and non-speech stimuli across electrode sites. TLE in childhood might be a good model for studying topographic and functional auditory processing and its neurodevelopment, pointing to MMN as a possible clinical tool for prognosis, evaluation, follow-up, and rehabilitation for TLE.