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The present paper aims to examine the potential of the Applied Element Method (AEM) in simulating the blast effects in RC panels. The numerical estimates are compared with the results obtained in an experimental campaign designed to investigate the effectiveness of fibre grout for strengthening full scale RC panels by comparing the effects that a similar blast load produces in a reference and the strengthened panel. First, a numerical model of the reference specimen was created in the software Extreme Loading for Structures and calibrated to match the experimental results. With no further calibration, the fibre reinforced grout strengthening was added and the resulting numerical model subjected to the same blast load. The experimental blast effects on both reference and strengthened panels, despite the lack of high speed measurement equipment (pressure, strains and displacements sensors), compare well with the numerical estimates in terms of residual and maximum displacements, showing that, once calibrated, the AEM numerical models can be successfully used to simulate blast effects in RC panels.

Fiber Reinforced Polymers (FRP) is a recent technique to strengthen timber structures and the studies available discussing the debonding between these materials are limited. Therefore, the bond assessment between FRP composites and timber substrates is a topic that needs clarification. The present work analyses the debonding process between Carbon (C) FRP laminates and timber with rupture modes consistent with Mode II interfacial fracture, i.e. with the sliding mode where the bond stresses act parallel to the plane of the bonding surface. Several single-lap shear tests were performed and the experiments showed a nonlinear local behaviour of the CFRP-to-timber interface. An interfacial bond-slip model and its calibration procedure were also presented. Furthermore, the calibrated nonlinear bond-slip model was implemented in a numerical approach where the FRP composite and the adhesive are simulated by linear and nonlinear springs and the substrate is assumed rigid. The following influences on the debonding process of the CFRP-to-timber interface were also analysed: (i) the bonding technique (Externally Bonded Reinforcement - EBR; and Near Surface Mounted - NSM); and (ii) the use of an additional device to mechanically anchor the CFRP laminate. Besides the determination of the effective bond length for each bonding technique, a new concept defining the length beyond which the force at the anchorage device does not decrease with the bonded length and a proposal to estimate its value for any bonded length was also presented and discussed. The experimental tests have shown that the NSM technique has a better performance compared to the EBR technique, independently of the installation of mechanical anchorage devices. In the case of the EBR technique, the strains in the CFRP laminate increased at its vicinities due to the clamping force applied to the anchors, which affected the final strength of the interface.

With the objective of having a solar thermoelectric system, running for 24 h a day along the different seasons of the year it is necessary to dimension the adequate storage and back-up systems. The choice of the back-up source of energy depends on how sustainable the power plant should be. In this study, the choice was the use of biomass in order to have a 100{%} renewable power plant. The selected site was the Alentejo region (Portugal). The local Direct Normal Irradiation (DNI) data was used to simulate with the System Advisor Model program (SAM) considering a solar system with north field and molten salt storage. The system needs no back-up during three months in a year. The use of biomass pellets is a viable alternative because it makes the power plant 100{%} renewable and dispatchable without loss of energy due to over-dimension of the expensive solar field and molten storage system.

This paper proposes a Tunnel FET (TFET)-based power management circuit (PMC) for ultra-low power RF energy harvesting applications. In contrast with conventional thermionic devices, the band-to-band tunneling mechanism of TFETs allows a better switching performance at sub-0.2 V operation. As a result, improved efficiencies in RF-powered circuits are achieved, thanks to increased rectification performance at low power levels and to the reduced energy required for a proper PMC operation. It is shown by simulations that heterojunction TFET devices designed with III-V materials can improve the rectification process at received power levels below-20 dBm (915 MHz) when compared to the application of homojunction III-V TFETs and Si FinFETs. For an available power of-25 dBm, the proposed converter is able to deliver 1.1 $μ }\text{W}$ of average power (with 0.5 V) to the output load with a boost efficiency of 86{%}.

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The strengthening of structures such as columns, beams, arches or slabs with Fibre Reinforced Polymers (FRP) has been the focus of several studies. However, the studies dedicated to the FRP debonding phenomenon of curved bonded joints affected by elevated temperatures are surprisingly limited and no studies on this topic are known, at present, to use nonlinear analytical or numerical approaches. Still, the available studies found in the literature are unanimous in affirming that the debonding phenomenon on such curved interfaces demands the interaction between Fracture Modes I and II. The present work aims to develop an analytical solution capable of simulating the debonding process of curved CFRP-toconcrete interfaces with a constant radius subjected to mechanical and/or thermal loads. Some examples are presented in which the influence of the radius of the interface and the temperature level is analysed. The analytical solution proposed here is based on adhesion laws in which, in the case ofMode II, an exponential bond vs. relative displacement law with temperature dependency is assumed, whereas the Mode I adhesive law is based on a linear with fragile rupture law with the same temperature dependency as Mode II.

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Neste artigo é apresentado um resumo das intervenções de conservação realizadas no século passado e dos estudos e testes não destrutivos realizados na última década na Igreja de São Leonardo na Atouguia da Baleia. Em seguida mostra-se o padrão de degradação que ocorre nos portais de arenito da igreja e é analisada a evolução da alveolização que ocorreu nos portais de arenito ao longo dos últimos sessenta a setenta anos. No final, a inspeção visual dos portais de arenito é comparada com um levantamento realizado através de varrimento por laser 3D.

tInspired by chitin based hierarchical structures observed in arthropods exoskeleton, this work reportsthe capturing of chitin nanowhiskers’ chiral nematic order into a chitosan matrix. For this purpose, highlycrystalline chitin nanowhiskers (CTNW) with spindle-like morphology and average aspect ratio of 24.9were produced by acid hydrolysis of chitin. CTNW were uniformly dispersed at different concentrationsin aqueous suspensions. The suspensions liquid crystalline phase domain was determined by rheologicalmeasurements and polarized optical microscopy (POM). Chitosan (CS) was added to the CTNW isotropic,biphasic and anisotropic suspensions and the solvent was evaporated to allow films formation. The Films’morphologies as well as the mechanical properties were explored. A correlation between experimentalresults and a theoretical model, for layered matrix’ structures with fibers acting as a reinforcement agent,was established. The results evidence the existence of two different layered structures, one formed bychitosan layers induced by the presence of chitin and another formed by chitin nanowhiskers layers.By playing on the ratio chitin/chitosan one layered structure or the other can be obtained allowing thetunning of materials’ mechanical properties.

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The cyclic shift graph of a monoid is the graph whose vertices are elements of the monoid and whose edges link elements that differ by a cyclic shift. For certain monoids connected with combinatorics, such as the plactic monoid (the monoid of Young tableaux) and the sylvester monoid (the monoid of binary search trees), connected components consist of elements that have the same evaluation (that is, contain the same number of each generating symbol). This paper discusses new results on the diameters of connected components of the cyclic shift graphs of the finite-rank analogues of these monoids, showing that the maximum diameter of a connected component is dependent only on the rank. The proof techniques are explained in the case of the sylvester monoid.

Crystal graphs, in the sense of Kashiwara, carry a natural monoid structure given by identifying words labelling vertices that appear in the same position of isomorphic components of the crystal. In the particular case of the crystal graph for the q-analogue of the special linear Lie algebra sln, this monoid is the celebrated plactic monoid, whose elements can be identified with Young tableaux. The crystal graph and the so-called Kashiwara operators interact beautifully with the combinatorics of Young tableaux and with the Robinson--Schensted correspondence and so provide powerful combinatorial tools to work with them. This paper constructs an analogous `quasi-crystal' structure for the hypoplactic monoid, whose elements can be identified with quasi-ribbon tableaux and whose connection with the theory of quasi-symmetric functions echoes the connection of the plactic monoid with the theory of symmetric functions. This quasi-crystal structure and the associated quasi-Kashiwara operators are shown to interact just as neatly with the combinatorics of quasi-ribbon tableaux and with the hypoplactic version of the Robinson--Schensted correspondence. A study is then made of the interaction of the crystal graph of the plactic monoid and the quasi-crystal graph for the hypoplactic monoid. Finally, the quasi-crystal structure is applied to prove some new results about the hypoplactic monoid.

Nowadays technology follows us everywhere. However, it is often overlooked when dealing with social issues, despite how easily it might improve the life of countless handicapped individuals. In other words, small pieces of software, under the form of games, can help the individual remain focus and go through treatments and therapies effortlessly. But game development is tricky because simply adopting a software development approach is not enough, as it assumes that games as a software can be developed through the commonly used systematic processes, yet these do have specific requirements. This paper proposes a new game development model to successfully deliver a quality serious game, towards social causes, bearing in mind the specific aspects both from games as a special kind of software and from the target players introducing a therapeutic/clinical perspective in the games development model.

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