Hydrogen permeation in parabolic trough receivers

The continued economic and population development puts additional pressure on the already scarce energetic sources. Thus there is a growing urge to adopt a sustainable plan able to meet the present and future energetic demands. Since the last two decades, solar trough technology has been demonstrating to be a reliable alternative to fossil fuels. Currently, the trough industry seeks, by optimizing energy conversion, to drive the cost of electricity down and therefore to place itself as main player in the next energetic age. One of the issues that lately have gained considerable relevance came from the observation of significant heat losses in a large number of receiver modules. These heat losses were attributed to slow permeation of traces of hydrogen gas through the steel tube wall into the vacuum annulus. The presence of hydrogen gas in the absorber tube results from the decomposition of heat transfer fluid due to the long-term exposure to 400°C. The permeated hydrogen acts as heat conduction mean leading to a decrease in the receivers performance and thus its lifetime. In order to prevent hydrogen accumulation, it has been common practice to incorporate hydrogen getters in the vacuum annulus of the receivers. Nevertheless these materials are not only expensive but their gas absorbing capacity can be insufficient to assure the required level of vacuum for the receivers to function. In this work the building of a permeation measurement device, vulnerabilities detected in the construction process and its overcome are described. Furthermore an experimental procedure was optimized and the obtained permeability results, of different samples were evaluated. The data was compared to measurements performed by an external entity. The reliability of the comparative data was also addressed. In the end conclusions on the permeability results for the different samples characteristics, feasibility of the measurement device are drawn and recommendations on future line of work were made.

Hygrothermal behaviour of earthen plasters for sustainable housing construction

A ready-mixed and several laboratory formulated mortars were produced and tested in fresh state and after hardening, simulating a masonry plaster for indoor application. All the mortars used a clayish earth from the same region and different compositions of aggregates, eventually including fibres and a phase change material. All the formulated mortars were composed by 1:3 volumetric proportions of earth and aggregate. Tests were developed for consistency, fresh bulk density, thermal conductivity, capillary absorption and drying, water vapour permeability and sorption-desorption. The use of PCM changed drastically the workability of the mortars and increased their capillary absorption. The use of fibres and variations on particle size distribution of the mixtures of sand that were used had no significant influence on tested properties. But particularly the good workability of these mortars and the high capacity of sorption and desorption was highlighted. With this capacity plasters made with these mortars are able to adsorb water vapour from indoor atmosphere when high levels of relative humidity exist and release water vapour when the indoor atmosphere became too dry. This fact makes them able to contribute passively for a healthier indoor environment. The technical, ecological and environmental advantages of the application of plasters with this type of mortars are emphasized, with the aim of contributing for an increased use for new or existent housing.

Adesão terapêutica e hipertensão arterial : o uso de fontes administrativas de dados de prescrição e levantamento de medicação na estimação da adesão à terapêutica com antagonistas dos recetores da angiotensina

RESUMO - Objetivos: São objetivos do presente estudo caraterizar a adesão terapêutica, primária e secundária, na Região de Saúde do Alentejo em utentes que seguiram tratamento para Hipertensão Arterial com Antagonistas dos Receptores da Angiotensina e constatar se a adopção de diferentes medidas produz diferentes resultados de adesão terapêutica. Metodologia: Este estudo é uma análise retrospetiva da prescrição e levantamento de ARA nos anos de 2010 e 2011 na Região de Saúde do Alentejo. Foram considerados 22.450 utentes e cinco diferentes medidas de adesão terapêutica: Rácio de Adesão Primária, Medication Possession Ratio, Compliance Rate, Refill Compliance Rate, Continuous Measure of Medication Gaps. Resultados: Constatou-se que a adesão terapêutica primária para os 22.450 utentes considerados na amostra foi de 0,612 (DP 0,325), a adesão terapêutica medida pelo indicador MPR foi de 0,557 (DP 0,380), pelo indicador CR foi de 0,697 (DP 0,517), pelo indicador RCR foi de 0,695 (DP 0,518) e pelo indicador CMG foi de 0,648 (DP 0,351). Independentemente do indicador considerado, a adesão terapêutica foi mais elevada no sexo feminino do que no sexo masculino, os utentes do sexo feminino apresentaram níveis de sobre-aquisição de medicação mais elevados e a prevalência de utentes que no período não chegaram a levantar nenhuma embalagem de medicação, não obstante a necessidade clínica ter sido identificada em pelo menos 2 momentos no período, foi mais elevada no sexo masculino. As faixas etárias acima dos 70 anos apresentaram níveis médios de adesão terapêutica significativamente superiores aos verificados nas faixas etárias que compreendem os utentes em idade ativa. Constatou-se que os concelhos que apresentaram resultados de adesão terapêutica inferiores à média amostral por um determinado indicador, em regra, viram confirmada essa tendência pelos restantes indicadores. Não obstante, verificou-se que os rankings de desempenho obtidos pelos cinco indicadores apresentaram concordância estatística fraca. Conclusões: Concluiu-se que, não obstante a existência de um conjunto de limitações e condicionalismos metodológicos, os dados atualmente recolhidos ao nível da prescrição e conferência de receituário permitem a mensuração dos comportamentos de adesão terapêutica. A inexistência de consenso científico terminológico tem conduzido à proliferação de indicadores com o fito de medir a adesão terapêutica que, sendo conceptualmente distintos na sua construção, conduzem a diferentes resultados de adesão terapêutica. Os resultados obtidos pelo presente estudo permitiram confirmar este aspecto pelo que não se recomenda a utilização de apenas um indicador para análise dos comportamentos de adesão terapêutica dos utentes.

Fair value measurement: Is the debate around level II and level III assets and liabilities relevant

Double Degree. A Work Project presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA- School of Business and Economics and a Masters Degree in Business Engineering from Louvain school of Management

Designing and implementing a performance measurement system in Auto Ribeiro, Lda.

In any business it is very important to measure the performance and it helps to select key information to make better decisions on time. This research focuses on the design and implementation of a performance measurement system in a Portuguese medium size firm operating in the specialized health care transformation vehicles industry. From the evidence that outputs from Auto Ribeiro’s current information system is misaligned with the company’s objectives and strategy, this research tries to solve this business problem through the development of a Balanced Scorecard analysis, although there are some issues, which deserve further development.

Starburst accelerator and incubator construction & energy: How to monitor the activities of an incubator and give strategic advice to startups

This work project takes the format of a problem-solving approach suggested by “Impulse Partners”, a French consulting firm. It recommends a way to measure the success of ten startups in the incubators “Starburst” and “Incubator Construction & Energy” and give them strategic guidance. A Balanced Scorecard is elaborated to help incubated startups building up and implementing their strategy. The Scorecard suggests possible initiatives for the startups that are ideally realized with the help of the consulting firm that is steering the incubator. Special attention is drawn to what the startups need to succeed, which typically concerns financing, networking and managing skills.

A new methodology for urban wind resource assessment

In the latest years the wind energy sector experienced an exponential growth all over the world. What started as a deployment of onshore projects, soon moved to offshore and, more recently to the urban environment within the context of smart cities and renewable micro-generation. However, urban wind projects using micro turbines do not have enough profit margins to enable the setup of comprehensive and expensive measurement campaigns, a standard procedure for the deployment of large wind parks. To respond to the wind assessment needs of the future smart cities a new and simple methodology for urban wind resource assessment was developed. This methodology is based on the construction of a surface involving a built area in order to estimate the wind potential by treating it as very complex orography. This is a straightforward methodology that allows estimating the sustainable urban wind potential, being suitable to map the urban wind resource in large areas. The methodology was applied to a case study and the results enabled the wind potential assessment of a large urban area being consistent with experimental data obtained in the case study area, with maximum deviations of the order of 10% (mean wind speed) and 20% (power density).

Construction sector: Need for strategic reorientation

The construction sector in Portugal declined sharply over the past 10 years. The current crisis can wiped out the entire industry. Can the industry survive? What lessons can we learn? What can be done to revive the sector? These are questions this study intends to answer. By analyzing the best practices of the industry and of the largest construction companies in Portugal, as well as the difficulties and constrains that they all faced, I found that retrenchment (operational costs and selling assets) are the main measures companies resort to, and that strategic reorientation is essential to turnaround. I found that internationalization is a key driver on strategic reorientation and diversification and concentration are complementary strategies that can enforce and strengthen the main one.

Mota-Engil Construction

Equity research report

Cylindrical spinning rotor gauge — A new approach for vacuum measurement

The spinning rotor gauge (SRG) is one of the most interesting vacuum gauges ever made, covering a pressure range of over seven orders of magnitude, with minimal gas interference (no pumping, ionization or heating of the measured gas), and a great stability of less than 1% drift per year. But despite its remarkable properties, apparently the SRG has not been further developed since the eighties, when it gained commercial interest. In this context, this dissertation aims at providing a starting point for a new line of investigation regarding this instrument, focused on the rotor itself. A brief study of different rotor geometries is provided, including a comparison between a cylindrical rotor and a spherical one. A cylindrical spinning rotor gauge (CSRG) is then proposed, based on the original SRG, but requiring a completely new lateral damping system. A prototype was built and tested against a non calibrated reference gauge.

Comparison of the fluorescent polarization (TDx) and the enzymatic competitive (EMIT 2000) immune assays for the measurement of cyclosporin A blood concentration

Evaluation of Cyclosporin A (CyA) blood concentration is imperative in solid organ transplantation in order to achieve maximal immunosuppression with the least side effects. We compared the results of whole blood concentrations of CyA in 50 blood samples simultaneously evaluated by the fluorescent polarization immune assay (TDx) and the enzymatic competitive immune assay (EMIT 2000). There was a strong correlation between both kits for any range of CyA blood concentration (R=0.99, p<0.001). The within-run and between-days coefficient of variation were less than 4% for both assays. The cost for each CyA measurement was 50% lower for the EMIT assay when compared to the TDx assay. We concluded that the EMIT is as accurate as the TDx in measuring CyA blood concentration and has the advantage of a lower cost, as well as the possibility of widespread access to the EMIT methodology in contrast to the TDx equipment, allowing the laboratory to perform several routines within a working day.

Visual politics of the estado novo realized on the Alameda Dom Afonso Henriques in Lisbon – the construction of ideal citizenship?

The stylistic categorization of the Estado Novo has been intensely discussed by Portuguese art historians. The square Alameda Dom Afonso Henriques in Lisbon (Alameda) can be seen as paradigmatic for the architecture of power of the Estado Novo. The Alameda forms a gardened valley between two hills. There you find two prominent and highly propagandist buildings: The Instituto Superior Técnico (IST) and the Fonte Luminosa are dedicated to modern sciences and respectively to the harmonious contribution of nature to the city. The iconography of the Alameda as well as its incorporation into the propagandist use of urban planning in the 1930s and 1940s exemplify the visual politics during Salazarism. Urban planning programs intended to create cities that would preserve the character of a traditional catholic society and at the same time answer to the need to modernize the country and evoke the image of a progressive state. Thus, public buildings and urban squares such as the Alameda contributed to design a corporate image and to the ‘spirit’ of the regime.

A behavioral perspective on the effects of using performance measurement systems in the companies: Evidence from a case study

The effects of PMSs on the people’s behaviour represent a high degree of relevance in the context of an organization performance and success. Thus, motivational and behavioural consequences of performance measurements are far from being totally understood (Franco-Santos et al., 2012). This work project (WP) purposes going further regarding the consequences/effects on people’s behaviour of using PMSs in organizations. The researcher conducted 11 interviews to managers during a nine-month internship as a controller in a Portuguese multi-national company. The evidence from this WP suggests that the way how managers understand a PMS determines a lot the way how they behave. Data also supports that PMSs influences in several ways motivation, perceptions, participation and job-related stress of managers.

Observations on dynamics of foraging hole construction of two leaf-feeding, soil-inhabiting Syntermes species (insecta: Isoptera) in an Amazonian Rainforest, Brazil

The intensity of construction of foraging access holes by two leaf-litter feeding, soil- inhabiting termite species, Syntermes molestus and Syntermes spinosus, in a Central Amazonian rain forest, was observed on consecutive nights for two weeks. Between 11 and 48 nest entrances per m2 were counted. Interaction between the two species was intense; some entrance holes were overtaken by the larger species during the observations; however, both species coexist in the area. A calculated minimum of 35 entrances/m2 is built every year by both species, emphasizing the importance of soil-burrowing termites for soil structure, aeration and water regime.