Embedded Multi-Core systems for Mixed Criticality applications in dynamic and changeable real-time environments

EMC2 finds solutions for dynamic adaptability in open systems. It provides handling of mixed criticality multicore applications in r eal-time conditions, withscalability and utmost flexibility, full-scale deployment and management of integrated tool chains, through the entire lifecycle.

A simplified four-branch model for the analytical study of the out-of-plane performance of regular stone URM walls

During the last years, several studies have been made aiming to assess the out-of-plane seismic response of unreinforced stone masonry structures. This fact led to the development of a wide variety of models and approaches, ranging from simple kinematic based analytical models up to complex numerical simulations. Nevertheless, for the sake of simplicity, the out-of-plane seismic response of a masonry wall pier may be obtained by means of a simple single-degree-of-freedom system while still providing good results. In fact, despite the assumptions associated with such a simple formulation, it is also true that the epistemic uncertainty inherent with the selection of appropriate input parameters in more complex models may render them truly ineffective. In this framework, this paper focuses on the study of the out-of-plane bending of unreinforced stone masonry walls (cantilevers) by proposing a simplified analytical approach based on the construction of a linearized four-branch model, which is used to characterize the linear and nonlinear response of such structural elements through an overturning moment-rotation relationship. The formulation of the four-branch model is presented and described in detail and the meaningful parameters used for its construction are obtained from a set of experimental laboratory tests performed on six full-scale unreinforced regular sacco stone masonry specimens. Moreover, a parametric analysis aiming to evaluate the effect of these parameters’ variation on the final configuration of the model is presented and critically discussed. Finally, the results obtained from the application of the developed four-branch model on real unreinforced regular sacco stone masonry walls are thoroughly analysed and the main conclusions obtained from its application are summarized.

Experimental characterization of the out-of-plane performance of regular stone masonry walls, including test setups and axial load influence

Stone masonry is one of the oldest and most worldwide used building techniques. Nevertheless, the structural response of masonry structures is complex and the effective knowledge about their mechanical behaviour is still limited. This fact is particularly notorious when dealing with the description of their out-of-plane behaviour under horizontal loadings, as is the case of the earthquake action. In this context, this paper describes an experimental program, conducted in laboratory environment, aiming at characterizing the out-of-plane behaviour of traditional unreinforced stone masonry walls. In the scope of this campaign, six full-scale sacco stone masonry specimens were fully characterised regarding their most important mechanic, geometric and dynamic features and were tested resorting to two different loading techniques under three distinct vertical pre-compression states; three of the specimens were subjected to an out-of-plane surface load by means of a system of airbags and the remaining were subjected to an out-of-plane horizontal line-load at the top. From the experiments it was possible to observe that both test setups were able to globally mobilize the out-of-plane response of the walls, which presented substantial displacement capacity, with ratios of ultimate displacement to the wall thickness ranging between 26 and 45 %, as well as good energy dissipation capacity. Finally, very interesting results were also obtained from a simple analytical model used herein to compute a set of experimental-based ratios, namely between the maximum stability displacement and the wall thickness for which a mean value of about 60 % was found.

Simulation of masonry out-of-plane failure modes by multi-body dynamics

The seismic assessment of the local failure modes in existing masonry buildings is currently based on the identification of the so-called local mechanisms, often associated with the out-of-plane wall behavior, whose stability is evaluated by static force-based approaches and, more recently, by some displacement-based proposals. Local mechanisms consist of kinematic chains of masonry portions, often regarded as rigid bodies, with geometric nonlinearity and concentrated nonlinearity in predefined contact regions (unilateral no-tension behavior, possible sliding with friction). In this work, the dynamic behavior of local mechanisms is simulated through multi-body dynamics, to obtain the nonlinear response with efficient time history analyses that directly take into account the characteristics of the ground motion. The amplification/filtering effects of the structure are considered within the input motion. The proposed approach is validated with experimental results of two full-scale shaking-table tests on stone masonry buildings: a sacco-stone masonry façade tested at Laboratório Nacional de Engenharia Civil and a two-storey double-leaf masonry building tested at European Centre for Training and Research in Earthquake Engineering (EUCENTRE).

Fluência de materiais

A presente dissertação apresenta uma abordagem ao tema Fluência, com um desenvolvimento geral para quatro materiais: madeira, alumínio, betão e aço. No entanto, particularizou-se este estudo apenas para dois destes materiais, a madeira e o alumínio. A madeira é um material viscoelástico, logo fortemente influenciado quando submetido a uma ação constante (Fluência) sendo agravada com alterações do teor em água. Iniciou-se o estudo, com uma introdução aos objetivos principais e a revisão teórica do conhecimento da propriedade mecânica (Fluência). Efetuou-se o estudo inicial para os quatro materiais indicados. Posteriormente, fez-se avaliação do efeito mecânico sortivo durante 60 dias com sete ciclos, em provetes de dimensões 20 x 20 x 400 mm3 (escala 1:10) de madeira de Eucalyptus globulus Labill. Recorrendo ao levantamento de um conjunto de modelos numéricos, procedeu-se ao ajuste e extrapolação do comportamento, em Fluência, para distintos períodos de tempo (1, 10 e 50 anos). Os resultados obtidos demonstraram que a madeira de Eucalipto não apresenta um limite no seu comportamento em Fluência, logo instável para os 60 dias de duração de ensaio. Os diferentes modelos de Fluência (x6) apresentaram uma variabilidade crescente de resultados, de acordo com o aumento de extrapolação dos resultados. Para a espécie de madeira de Eucalipto constatou-se ainda, que o ajuste e extrapolação de deformação para 50 anos ultrapassaram os valores sugeridos pelo Eurocódigo 5. A última parte deste trabalho, incidiu sobre o desenvolvimento da metodologia do ensaio em flexão de 3 provetes de alumínio similares, cujas dimensões eram de 20 x 20 x 400mm3. O objetivo desta metodologia foi avaliar o seu comportamento em Fluência. Numa primeira fase, foi aplicada uma carga contante de 160 kN. E numa segunda fase, foi aplicada o dobro dessa carga sujeita adicionalmente a uma temperatura bastante superior à temperatura ambiente (a rondar os 50 oC). Conclusivamente verificou-se que o alumínio não apresenta deformação por Fluência, para as condições de ensaio apresentadas.

Caracterização da intervenção da Fisioterapia em indivíduos com dor crónica lombar, e seus resultados a nível da dor e capacidade funcional

RESUMO: Objectivo: Este trabalho teve como objectivo contribuir para o processo de adaptação cultural da Quebec Back Pain Disability Scale (QBPDS), através do estudo da sua Validade de Constructo e Poder de Resposta, e caracterizar a intervenção realizada pela fisioterapia (FT) e os resultados obtidos em utentes com dor crónica lombar (DCL). Introdução: A redução da incapacidade funcional associada à DCL é um dos principais objectivos e resultados da intervenção da FT nestes utentes. Com o intuito de proceder à sua avaliação, pode recorrer-se a um conjunto de diferentes instrumentos de medida, sendo a QBPDS uma das escalas mais utilizadas para medir a incapacidade. Embora esta tenha sido anteriormente adaptada para a população portuguesa, não foram determinadas as suas propriedades psicométricas. Por outro lado, apesar da literatura referir que os serviços de FT são bastante procurados por indivíduos com DCL, em Portugal, a informação existente sobre a prática da FT nesta condição clínica e sobre os resultados obtidos é ainda escassa. Metodologia: Recorreu-se a um estudo de coorte prospectivo com uma amostra de conveniência, constituída por 119 indivíduos com DCL, que iniciaram fisioterapia em 16 centros/ hospitais/ clínicas de Fisioterapia/ utentes no domicílio, e cumpriam os critérios de inclusão e exclusão estabelecidos. Os utentes foram avaliados no momento pré-intervenção e num segundo momento até 6 semanas depois. As propriedades psicométricas da Quebec Back Pain Disability Scale –Versão Portuguesa (QBPDS-VP) avaliadas foram a Validade de Constructo e o Poder de Resposta. Posteriormente procedeu-se à caracterizar a prática da FT quanto às modalidades utilizadas, número de sessões de tratamento e duração do episódio de cuidados. Adicionalmente descreveu-se os resultados obtidos após a intervenção da FT, ao nível da dor e incapacidade. Resultados: Os resultados revelaram um resultado positivo para a Validade de Constructo da QBPDS-VP e um elevado Poder de Resposta (área abaixo da curva ROC = 0,736; IC95%=0,639-0,833). Apresenta ainda uma diferença mínima clinicamente importante (DMCI) de 7 pontos (sensibilidade =72,4% e especificidade = 69,8%). Aquando da intervenção da FT em casos de DCL, existe uma grande diversidade de modalidades realizadas combinadas em diferentes pacotes de intervenção, e verificou-se um número médio de sessões realizadas de 14,22 visitas por utente, numa duração de episódio de cuidados maioritariamente superior a 6 semanas. Os resultados da intervenção revelaram uma redução significativa da incapacidade funcional e da intensidade da dor (z= -7,440 e z=-6,625; respectivamente, p=0,000). Conclusão: Os resultados do presente estudo revelam que a QBPDS-VP possui uma boa Validade de Constructo e Poder de Resposta. Revela ainda que a intervenção da FT em casos de DCL, apesar de apresentar grande diversidade nas modalidades utilizadas por vezes até divergentes das recomendações dadas pelas normas de orientação clínica, e uma duração do episódio de cuidados aparentemente superior aos dados fornecidos pela literatura; proporciona uma redução significativa dos níveis de dor e incapacidade em utentes com DCL.------------ ABSTRACT: Objective: The aim of this study is to contribute to the process of cultural adaptation of the Quebec Back Pain Disability Scale (QBPDS), through the study of its Construct Validity and Responsiveness, and characterize the intervention performed by physical therapy (PT) and the results in patients with chronic low back pain (CLBP). Introduction: The reduction in functional disability associated with CLBP is one of the main purpose and results of physical therapy intervention in these patients. With the intention of evaluating them, the professionals can resort to a set of different measuring instruments, and the QBPDS is one of the most commonly used scales for measuring disability. Although this has been previously adapted for the Portuguese population, it was not determined its psychometric properties. Moreover, despite the literature noted that services for PT are quite sought by individuals with CLBP, in Portugal, the existing information on the practice of PT in this clinical condition and the results obtained are still scarce. Methodology: It was used a prospective cohort study with a convenience sample consisting of 119 individuals with CLBP, who started therapy at 16 centers / hospitals / Physiotherapy clinics / household physiotherapy, and fulfiled the inclusion and exclusion criteria established . The patients were assessed at pre-intervention and a second time after 6 weeks. Psychometric properties of the Quebec Back Pain Disability Scale-Portuguese version (QBPDS-VP) were evaluated to construct validity and responsiveness. Subsequently, it was proceeded to the characterization the practice of FT regarding to the modalities used, the number of treatment sessions and duration of the episode of care. Additionally it was described the results obtained after the intervention of the PT, the level of pain and the disability. Results: The results revealed a positive result for the Construct Validity of the QBPDS- VP and a high responsiveness (area under the ROC curve = 0.736, 95% CI 0.639 to 0.833). Minimal clinically important difference (MCID) also presents a 7-point (sensitivity = 72.4% and specificity = 69.8%). In the PT intervention in cases of CLBP there is a great diversity of procedures performed combined in different packages intervention, and it was found an average number of sessions of 14.22 visits per user, with a duration of the episode of care mostly higher to 6 weeks. The results of the intervention showed a significant reduction of disability and pain intensity (z = -7.440 z = -6.625, respectively, p = 0.000).Conclusion: The results of this study show that QBPDS-VP has a good construct validity and responsiveness. It also reveals that the PT intervention in cases of CLBP, despite showing great diversity in the methods used, that sometimes are also divergent to the recommendations given by clinical guidelines, and with a duration of episode of care apparently superior to data provided by the literature, provides an significant reduction in the levels of pain and disability in patients with DCL.

Thermal performance of cool facades: evaluation by Infrared Thermography

High reflective paints (cool paints) are used on flat roofs to reduce heat gains from the incidence of solar radiation and thus improve the thermal comfort and energy efficiency of buildings, especially in summer periods. Given the application potential of these paints on vertical surfaces, a research study has been developed to evaluate the thermal performance of reflective paints on walls under real exposure conditions. Accordingly, different reflective paints have been applied as the final coating of an ETICS type solution, on the facades of a full scale experimental cell built at LNEC campus. For being applied in an ETICS system a paint has to fulfill several requirements, whether aesthetic or functional (such as the adhesion between the coating layers or the durability of the insulation), essential for its efficient performance. Since this construction coating system is subject to a prolonged sun exposure, various problems may arise, such as paint degradation or deterioration of the thermal insulation properties, particularly when dark colors are applied. To evaluate the thermal performance of the chosen paints, the method of non-destructive analysis by Infrared Thermography was used. Thermography allows knowing the temperature distribution of facades by measuring the radiation emitted by their surfaces. To complement the thermographic diagnosis, thermocouples were placed between the insulation and the paint system of the experimental cell. Additional laboratory tests allowed the characterization of the optical properties (reflectance and emittance) of the different reflective paints used in this study. The comparative analysis of the thermal performance of reflective and conventional paints revealed that the reflective paint allows a reduction of the facade surface temperature, reducing the risk of loss of insulating properties of the ETICS system and thus ensuring its longevity and functionality. The color of the paint used affects, naturally, the reflective ability of the surface and may have an important role in energy balance of the building. This paper also showed the potential of infrared thermography in the evaluation of the thermal performance of reflective paints.

The effect of key process operational conditions on enhanced biological phosphorus removal from wastewater

Enhanced biological phosphorus removal (EBPR) is the most economic and sustainable option used in wastewater treatment plants (WWTPs) for phosphorus removal. In this process it is important to control the competition between polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), since EBPR deterioration or failure can be related with the proliferation of GAOs over PAOs. This thesis is focused on the effect of operational conditions (volatile fatty acid (VFA) composition, dissolved oxygen (DO) concentration and organic carbon loading) on PAO and GAO metabolism. The knowledge about the effect of these operational conditions on EBPR metabolism is very important, since they represent key factors that impact WWTPs performance and sustainability. Substrate competition between the anaerobic uptake of acetate and propionate (the main VFAs present in WWTPs) was shown in this work to be a relevant factor affecting PAO metabolism, and a metabolic model was developed that successfully describes this effect. Interestingly, the aerobic metabolism of PAOs was not affected by different VFA compositions, since the aerobic kinetic parameters for phosphorus uptake, polyhydroxyalkanoates (PHAs) degradation and glycogen production were relatively independent of acetate or propionate concentration. This is very relevant for WWTPs, since it will simplify the calibration procedure for metabolic models, facilitating their use for full-scale systems. The DO concentration and aerobic hydraulic retention time (HRT) affected the PAO-GAO competition, where low DO levels or lower aerobic HRT was more favourable for PAOs than GAOs. Indeed, the oxygen affinity coefficient was significantly higher for GAOs than PAOs, showing that PAOs were far superior at scavenging for the often limited oxygen levels in WWTPs. The operation of WWTPs with low aeration is of high importance for full-scale systems, since it decreases the energetic costs and can potentially improve WWTP sustainability. Extended periods of low organic carbon load, which are the most common conditions that exist in full-scale WWTPs, also had an impact on PAO and GAO activity. GAOs exhibited a substantially higher biomass decay rate as compared to PAOs under these conditions, which revealed a higher survival capacity for PAOs, representing an advantage for PAOs in EBPR processes. This superior survival capacity of PAOs under conditions more closely resembling a full-scale environment was linked with their ability to maintain a residual level of PHA reserves for longer than GAOs, providing them with an effective energy source for aerobic maintenance processes. Overall, this work shows that each of these key operational conditions play an important role in the PAO-GAO competition and should be considered in WWTP models in order to improve EBPR processes.

Assessment of the efficiency of prefabricated hybrid composite plates (HCPs) for retrofitting of damaged interior RC beam–column joints

The effectiveness of prefabricated hybrid composite plates (HCPs) as a seismic retrofitting solution for damaged interior RC beam-column joints is experimentally studied. HCP is composed of a thin plate made of strain hardening cementitious composite (SHCC) reinforced with CFRP sheets/laminates. Two full-scale severely damaged interior beam-column joints are retrofitted using two different configurations of HCPs. The effectiveness of these retrofitting solutions mainly in terms of hysteretic response, dissipated energy, degradation of secant stiffness, displacement ductility and failure modes are compared to their virgin states. According to these criteria, both solutions resulted in superior responses regarding the ones registered in their virgin states.

High strain rate constitutive modeling forhistorical structures subjected to blast loading

Doctoral Thesis Civil Engineering

Diagnóstico e ensaio de carga de asnas tradicionais de madeira

Dissertação de mestrado Integrado em Engenharia Civil

The appraisal of mesophilic anaerobic digestion and thermophilic aerobic digestion in the treatment of municipal sludge in Ireland

It has been well documented that the optimum feedstock for anaerobic digesters consists of readily biodegradable compounds, as found in primary sludge or even a mixed substrate of primary and excess activated sludge. Due to the requirements of the Urban Wastewater Treatment Plant Directive of 1991, the quantities of secondary sludge generated is set to increase substantially. A pilot scale study was undertaken to evaluate the performance of both Mesophilic Anaerobic Digestion and Thermophilic Aerobic digestion in the treatment of secondary sludge. The results indicated that the anaerobic pilot scale digester achieved a greater solids destruction than the aerobic pilot plant averaging at 28% T.S. removal verses 20% for the aerobic digester, despite the fact that secondary sludge is the optimum feedstock for aerobic digestion. This can, however, be attributed to the greater biomass yield experienced with aerobic systems, and to the absence of Autothermal conditions. At present, the traditional technique of Mesophilic Anaerobic Digestion is in widespread application throughout Ireland, for the stabilisation of sewage sludge. There is only one Autothermal Thermophilic Aerobic Digester at present situated in Killarney, Co. Kerry. A further objectives of the study was to compare full-scale applications of Mesophilic Anaerobic Digestion to ATAD. Two Sludge Treatment plants, situated in Co. Kerry, were used for this purpose, and were assessed mainly under the following headings; process stability, solids reduction on average, the ATAD plant in Killarney has the advantage of producing a “Class A” Biosolid in terms of pathogen reduction, and can effectively treat double the quantity of sludge. In addition, economically the ATAD plant is cheaper to run, costing €190 / t.d.s verses €211 / t.d.s. for the anaerobic digester in Tralee. An overview of additional operational Anaerobic Digestion Plants throughout Ireland is also presented.

The appraisal of anaerobic digestion in Ireland to develop improved designs and operational practice

Mesophilic Anaerobic Digestion treating sewage sludge was investigated at five full-scale sewage treatment plants in Ireland. The anaerobic digestion plants are compared and evaluated in terms of design, equipment, operation, monitoring and management. All digesters are cylindrical, gas mixed and heated Continuously Stirred Tank Reactors (CSTR), varying in size from 130m3 to 800m3. Heat exchanger systems heat all digesters. Three plants reported difficulties with the heating systems ranging from blockages to insufficient insulation and design. Exchangers were modified and replaced within one year of operation at two plants. All but one plant had Combined Heat and Power (CHP) systems installed. Parameter monitoring is a problem at all plants mainly due to a lack of staff and knowledge. The plant operators consider pH and temperature the most important parameters to be measured in terms of successful monitoring of an anaerobic digester. The short time taken and the ease at which pH and temperature can be measured may favour these parameters. Three laboratory scale pilot anaerobic digesters were operated using a variety of feeds over at 144-day period. Two of the pilots were unmixed and the third was mechanically mixed. As expected the unmixed reactors removed more COD by retention of solids in the digesters but also produced greater quantities of biogas than the mixed digester, especially when low solids feed such as whey was used. The mixed digester broke down more solids due to the superior contact between the substrate and the biomass. All three reactors showed good performance results for whey and sewage solids. Scum formation occurred giving operational problems for mixed and unmixed reactors when cattle slurry was used as the main feed source. The pilot test was also used to investigate which parameters were the best indicators of process instability. These trials clearly indicated that total Volatile Fatty Acid (VFA) concentrations was the best parameter to show signs of early process imbalance, while methane composition in the biogas was good to indicate possible nutrient deficiencies in the feed and oxygen shocks. pH was found to be a good process parameter only if the wastewater being treated produced low bicarbonate alkalinities during treatment.

Numerical simulation of combined heat transfer phenomena (conduction, convection, and radiation). Application to he optimisation of thermal systems

Thermal systems interchanging heat and mass by conduction, convection, radiation (solar and thermal ) occur in many engineering applications like energy storage by solar collectors, window glazing in buildings, refrigeration of plastic moulds, air handling units etc. Often these thermal systems are composed of various elements for example a building with wall, windows, rooms, etc. It would be of particular interest to have a modular thermal system which is formed by connecting different modules for the elements, flexibility to use and change models for individual elements, add or remove elements without changing the entire code. A numerical approach to handle the heat transfer and fluid flow in such systems helps in saving the full scale experiment time, cost and also aids optimisation of parameters of the system. In subsequent sections are presented a short summary of the work done until now on the orientation of the thesis in the field of numerical methods for heat transfer and fluid flow applications, the work in process and the future work.

La médecine de famille en Suisse à l'horizon 2030: quelle place pour la délégation des tâches médicales. [Family practitioners in Switzerland by 2030: which roles for medical task delegation?]

Due to population aging, by 2030 Switzerland may face a demand of 24 million family practitioner visits, a growth of 13 percent from the 2005 level. This result is based on the assumption that the per capita demand for doctor visits remains what was observed in 2005 by age groups and sex. During the same period, the total number of practitioners may decrease by 14 percent whereas the female proportion of such practitioners may double. These changes may cause a 33 percent decrease in the supply of physician visits to reach only 14 millions. The comparison of the demand and supply of family doctor visits reveals that by 2030, 10 million visits may be unmet which represents 40 percent of the demand. On the supply side, a full scale implementation of task delegation may partially reduce that gap (minus 2 millions). On the demand side, improved health status may bring in a larger decrease in the needs for visits (minus 4 million).