Com o crescente consumo de energia elétrica são cada vez mais os países que procuram fontes de energia renovável e limpa, entre elas a eólica. A quantidade de energia produzida é influenciada pela altura das torres, dimensões das pás e potência dos aerogeradores. Quanto maior for a elevação da turbina maiores são a velocidade e estabilidade dos ventos alcançados. A solução de torre treliçada em concreto armado pré-moldado idealizada por Lúcio e Chastre [2] permite a construção de torres altas e é competitiva em relação aos outros sistemas estruturais.As ligações têm uma importância fundamental no comportamento global das estruturas pré-moldadas. A viabilidade da ligação (fácil execução, baixo custo, comportamento/capacidade resistente) é preponderante na viabilização da construção destas torres.Até à data foram estudadas quatro ligações (S1, S2, S3 e S4), sendo neste artigo abordadas apenas as ligações do modelo S3 com junta de 3mm (barras salientes/bainhas corrugadas/selagem com grout) e do modelo S4 com junta de 50 mm (ligações aparafusadas produzidas comercialmente).Através dos resultados experimentais pode-se concluir que o mecanismo de rutura foi o mesmo nos dois modelos e que as soluções estudadas preenchem os requisitos para a sua utilização em estruturas pré-moldadas de concreto armado para suporte de aerogeradores.

Este artigo avalia se, para especificações de betão correntes, a resistência à compressão de betão pronto é significativamente dependente da central que o produziu, bem como se a variabilidade entre amassaduras de uma determinada composição é dependente da classe de resistência especificada. É apresentado um parâmetro probabilístico que converte a resistência à compressão característica especificada para a resistência à compressão expectável em provetes de betão cúbicos em condições padronizadas.É feita uma análise estatística e probabilística dos resultados de ensaios de resistência à compressão aos 28 dias de betão pronto produzido em três centrais de betão portuguesas durante o ano de 2017. Após a avaliação da representatividade da base de dados analisada, é feito um estudo comparativo dos parâmetros estatísticos dos dados de produção das diferentes centrais e é avaliada a influência da classe de resistência à compressão do betão nestes parâmetros. Define-se e analisa-se um parâmetro probabilístico que converte a resistência à compressão especificada para a resistência potencial de betão, para cubos de 150 mm. Este parâmetro contribui para uma futura proposta de um modelo probabilístico, a ser utilizado em análises de fiabilidade, que converte a resistência à compressão especificada para a resistência à compressão de elementos de betão em obra.Quer a análise estatística dos ensaios de resistência à compressão, quer o parâmetro de conversão são comparados com os resultados de investigações internacionais na área, aferindo-se se a qualidade da produção de betão pronto nacional é semelhante à de outras regiões.

Power Hardware-in-the-Loop (PHiL) system for asynchronous electric drives application based on power inverter with Field Programmable Gate Array (FPGA)-based control system is discussed. Proposed PHiL structure and scheme for asynchronous electric drives are under discussion as well. Described PHiL can be used for power inverters multi-stage testing.

Additive manufacturing (commonly known as 3D printing or rapid prototyping) refers to processes used to produce parts in an additive manner by means of computer-aided design (CAD). While additive manufacturing is a technology that can be used in many different application areas, this project focuses on future trends in additive manufacturing (AM) aimed at improving biological functionality (bio-AM) and on its opportunities, barriers and challenges. The big advantage of this technique is that small batches can be produced more economically than with any other manufacturing process. Virtually any structure can be customized, which is particularly important in the healthcare sector. Possible applications include biological implants such as organs and tissues, nutrients, drugs and their transport mechanisms, equipment such as surgical knives and drilling guides, tissues for research, development and training, and personalized prostheses, supports and exoskeletons. Besides exploring such applications, the project will also systematically analyze potential "human enhancement" uses of AM technology and developments in the emerging do-it-yourself (DIY) cultures ("bio/body-hacking"; cyborgism; open source 3D printing movement).

In the first phase of the project, the technological state of the art will be analyzed, as will a wide variety of non-technical aspects, regulatory issues and future trends, also with a special focus on sociotechnical imaginaries (e.g., in science fiction), human enhancement and DIY cultures. This horizon scanning will be accomplished partly by means of expert and stakeholder interviews.

In the second phase, the project will use a variety of foresight and technology assessment methods and will carry out a 360° envisioning exercise with contributions by external experts, entailing an in-depth analysis of selected applications of bio-AM.

The project work will end with a scenario development phase in which the focus will be on likely outcomes of already emerging developments, though further-reaching future perspectives will be taken into account to a certain extent. Taken together, these scenarios will allow for both a broader understanding of the wide range of potential impacts of AM applications and a clearer picture of potential policy challenges relevant to the Members of the European Parliament.

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Nowadays technologies relate to so many aspects in our daily life that makes society eager for more and more ways of using it. To keep up with this new technological world, all economic sectors, from industry to services, are trying to adapt their products into this new reality. Presently, cultural heritage is already a field where the application of technology allows a static site to be converted into an intelligent environment, with detailed information about a specific monument or historical place, becoming more interesting, not only for local habitants, but also for tourists. This paper describes an application that allows tourists, managers and historical sites' habitants to experience a completely new way of discovering those places, offering a visit with detailed real-time information taking into account their personal interests. Tourists will have at their disposal a full set of optimized routes, combining their interests with their visiting time.

This paper presents a study of the behaviour and load capacity of Steel Fibre Reinforced Concrete (SFRC) flat slabs under monotonically increased concentrated vertical loads. The SFRC was used only in the local region of the slab-column connection, as the rest of the slab was cast using normal concrete (NC) without fibres. The six experimental test specimens had a thickness of 150 mm with different longitudinal reinforcement ratios, using a non-uniform distribution over the slab width. The concretes used were made with different Dramix® 4D 65/60 BG steel fibre contents (0%, 0.5 %, 0.75% and 1.0% volume content). The slab tests were complemented by flexural tests on notched-beams. This made it possible to determine the tension behaviour of the different concretes used, through a linear post-cracking behavior and inverse analysis. The inverse analysis made it possible to define the stress-crack opening relationship that characterize the tension behaviour of SFRC and to relate it to the observed behaviour and load capacity of the tested slabs. The tests results show that the tensile behaviour of the SFRC plays an important role in the behavioural and load capacity of the slabs and that it can be considered relevant to physically based models.

This paper presents an experimental study of four flat slab specimens subjected to combined vertical and horizontal cyclic loading. Steel fibre-reinforced concrete (SFRC) was used only in the local region of the slab–column connection, while the rest of the slabs were cast using normal concrete. The specimens measured 4·15 m × 1·85 m × 0·15 m and were connected to two steel half columns by 0·25 m × 0·25 m rigid steel plates, prestressed against the slab using steel bolts, to ensure monolithic behaviour. The specimens were tested using an innovative test setup system that accounted for important factors, such as the ability of bending moment redistribution, line of inflection mobility and assured equal vertical displacements at the opposite slab borders, and symmetrical shear forces. Results show that the presence of SFRC in the slab–column connection region is effective in increasing the deformation capacity of slab–column connections, allowing the increase of horizontal drift ratios.

The present study aims to understand the potentialities and implications,
to the teacher and her practice, of the use of formative assessment with the support
of educational technology.
Regarding the research methodology, this study is part of the research on own
practice. The participants were the teacher, who was simultaneously a researcher,
and the students of a 9th grade class.
In the course of this experience it was found that the use of formative assessment
allows, on the one hand, the student to realize what he manages to understand, and
what he has to do to overcome what are less consolidated parts of the content in
study; and, on the other, the teacher to detect in a timely manner the difficulties of
the student and to change strategies to allow the student to overcome his difficulties.
The lack of time, the difficulties in managing the curriculum and the existence of
national exams are three of the main obstacles mentioned by the teachers for the
non-realization of formative assessment. In this experience it was found that the use
of new technologies turns possible to overcome these limitations.
This type of assessment had a very positive impact on teacher’s practice and in the
learning of the students.
Keywords: assessment; formative assessment; new technologies.

A aprendizagem de leitura implica no desenvolvimento de competências e habilidades e as TICs possuem o papel de gerar estratégias de relação com o saber. Esta pesquisa identifica competências para uma maior autonomia do sujeito em leitura, via relação entre as tecnologias da informação e comunicação e outros letramentos, através da investigação sobre a prática pedagógica de letramento digital na escola fundamental, no sétimo ano. O método consiste em um estudo, de caráter quantitativo, no qual são analisados os contextos de uso do letramento digital, a junção de diversos outros letramentos e habilidades subjacentes ao letramento digital e a interrelação com plataformas (de gestão de aprendizagem, imagens e vídeos), tecnologias para publicação e partilha de conteúdos, tecnologias de colaboração e construção, redes sociais e tecnologias de comunicação interpessoal. Depois, uma abordagem complementar de investigação-ação Design-Based Research (Db-R) estuda de que forma deve o professor trabalhar com os alunos para favorecer essa autonomia. Os resultados apontam para um conjunto de ações, nas políticas públicas nas práticas pedagógicas, com medidas a superar as dificuldades e os atavismos, com a inserção dos estudantes em práticas com letramento digital e emprego de ferramentas e recursos desenvolvidos de modo específico para o público final. Palavras-chave: Db-R, Letramento, TIC.

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Compressive stresses created by lateral external pressure on laminates are an important factor on success of the use of mechanical anchorage of externally bonded reinforcement (EBR). A program of double shear tests with imposed normal stresses on GFRP plates bonded to a concrete surface and a bond-slip model are described. Results generated numerically are summarized and used as reference values against those obtained after accelerated aging by freeze-thaw cycles, and temperature cycles of the same amplitude but range closer to the glass vitreous temperature. Numerical modelling showed that the bonded length is fully stressed prior to failure. Increasing lateral pressure led to a larger maximum bond stress and strength at the interface. Cohesion, fracture energy and internal friction angle changes are calculated and used to analyze the effects of the aforementioned cycles on the expected behaviour of the GFRP-concrete joints, namely at the interface.

In this paper we deal with analog active filter design using discrete components taking into consideration tolerance effects. Sensitivity analysis is performed to determine the most influential components in the considered circuit, thus relative higher precision is offered to those parameters. Further, an in-loop optimization technique is considered, thus actual IC models are handled. An application example is presented. HSpice simulation results, supported by Monte Carlo analysis, are given to highlight efficiency of the proposed selection technique.

Cellulosomes are sophisticated multi-enzymatic nanomachines produced by anaerobes to effectively deconstruct plant structural carbohydrates. Cellulosome assembly involves the binding of enzyme-borne dockerins (Doc) to repeated cohesin (Coh) modules located in a non-catalytic scaffoldin. Docs appended to cellulosomal enzymes generally present two similar Coh-binding interfaces supporting a dual-binding mode, which may confer increased positional adjustment of the different complex components. Ruminococcus flavefaciens’ cellulosome is assembled from a repertoire of 223 Doc-containing proteins classified into 6 groups. Recent studies revealed that Docs of groups 3 and 6 are recruited to the cellulosome via a single-binding mode mechanism with an adaptor scaffoldin. To investigate the extent to which the single-binding mode contributes to the assembly of R. flavefaciens cellulosome, the structures of two group 1 Docs bound to Cohs of primary (ScaA) and adaptor (ScaB) scaffoldins were solved. The data revealed that group 1 Docs display a conserved mechanism of Coh recognition involving a single-binding mode. Therefore, in contrast to all cellulosomes described to date, the assembly of R. flavefaciens cellulosome involves single but not dual-binding mode Docs. Thus, this work reveals a novel mechanism of cellulosome assembly and challenges the ubiquitous implication of the dual-binding mode in the acquisition of cellulosome flexibility.