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2019
Marques, Marta, Bruno J. Guerreiro, Rita Cunha, and Carlos Silvestre. "Trajectory planning and control for drone replacement for multidrone cinematography." 21st IFAC Symposium on Automatic Control in Aerospace (ACA 2019), IFAC-PapersOnLine. Vol. 52. 2019. 334-339. Abstract
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Torrisi, Giacomo, João S. Luis, Olalla Sanchez-Sobrado, Rosario Raciti, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, Rodrigo Martins, and Antonio Terrasi. "{Colloidal-structured metallic micro-grids: High performance transparent electrodes in the red and infrared range}." Solar Energy Materials and Solar Cells. 197 (2019): 7-12. Abstract

One of the most promising approaches to produce industrial-compatible Transparent Conducting Materials (TCMs) with excellent characteristics is the fabrication of TCO/metal/TCO multilayers. In this article, we report on the electro-optical properties of a novel high-performing TCO/metal/TCO structure in which the intra-layer is a micro-structured metallic grid instead of a continuous thin film. The grid is obtained by evaporation of Ag through a mask of polystyrene colloidal micro-spheres deposited by the Langmuir-Blodgett method and partially dry-etched in plasma. IZO/Ag grid/IZO structures with different thicknesses and mesh dimensions have been fabricated, exhibiting excellent electrical characteristics (sheet resistance below 10 $Ømega$/□) and particularly high optical transmittance in the near-infrared spectral region as compared to planar (unstructured) TCM multilayers. Numerical simulations were also used to highlight the role of the Ag mesh parameters on the electrical properties.

Caeiro, Frederico, L{\'ı}gia Henriques-Rodrigues, and Dora Prata Gomes. "A simple class of reduced bias kernel estimators of extreme value parameters." Computational and Mathematical Methods (2019): e1025. AbstractWebsite
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Gavinho, Sílvia R., Pedro R. Prezas, Diogo J. Ramos, Isabel Sá‐Nogueira, Joao P. Borges, Carmo M. Lança, Jorge C. Silva, Célia MR Henriques, Eduardo Pires, Jakka Suresh Kumar, and M. P. F. Graça. "{Nontoxic glasses: Preparation, structural, electrical and biological properties}." International Journal of Applied Ceramic Technology (2019): ijac.13243. AbstractWebsite
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Alexandre, Miguel, Manuel Chapa, Sirazul Haque, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{Optimum Luminescent Down-Shifting Properties for High Efficiency and Stable Perovskite Solar Cells}." ACS Applied Energy Materials. 2 (2019): 2930-2938. AbstractWebsite
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Silva, Sara, Maria João Falcão Silva, Paula Couto, and Fernando Pinho. "Energetic Rehabilitation of Building Towards BIM Methodology." CIAC2019 - 1st Conference on Automation Innovation in Construction. Leiria 2019.
Pinho, Fernando F. S. "Curso de pós-Graduação em Construção e Reabilitação Sustentável da FCT NOVA." Jornal de Negócios. Ano XVI, Nº 4046 (2019).
Brandao Moniz, António, and Bettina-Johanna Krings. "Social conditions of human-machine interaction: decision, control, qualilification." Kolloquium at Weizenbaum Institute (2019). Berlin: Weizenbaum Institute, WZB, 2019. Abstract

Due to the ongoing technical advancements in robotics, new organizational and occupational impacts are expected in different sectors. The contribution of António Moniz and Bettina-Johanna Krings focuses on the social conditions under which technology is embedded into production processes. Thus, social distribution processes, demographic change, sustainability becomes more and more important when reflecting about "technology futures".
In particular they will ask:
How does automation change work & working conditions?
Which expectations on technology are strengthen-ing the concepts of work?
Which regulations and ethics principles must be considered (safety, autonomy, control)?
Which new competences and qualification dimen-sions will be raised for non-routine tasks in auto-mated environments?
Which new types of human-machine interaction can be developed with increased cyber-physical system application at the shopfloor?

da Silva, Pedro Boto Semblano, Corneliu Cismasiu, and José Vieira de Lemos. "Avaliação da vulnerabilidade sísmica de um arco em alvenaria utilizando o método dos elementos discretos." SÍSMICA 2019 - 11º Congresso Nacional de Sismologia e Enhenharia Sísmica. Lisboa 2019. final_sismica2019.pdf
Brandao Moniz, António. "Emerging problems of human-machine interaction and innovative solutions." Séminaire CRAN-Centre de Recherche en Automatique de Nancy. Nancy: Université de Nancy, 2019.
Rebelo, H. B., D. Lecompte, C. Cismaşiu, A. Jonet, B. Belkassem, and A. Maazoun. "3D printed PLA sacrificial honeycomb cladding blast mitigation." 18th International Symposium for the Interaction of Munitions with Structures (ISIEMS). Panama City Beach, FL, USA 2019.
Yang, Yongming, Hugo Biscaia, Manuel A. G. Silva, and Carlos Chastre. "Monotonic and quasi-static cyclic bond response of CFRP-to-steel joints after salt fog exposure." Composites Part B: Engineering. 168 (2019): 532-549. AbstractWebsite

Deterioration of adhesively bonded CFRP/steel systems in salt fog environment, i.e., deicing salts and ocean environments, has to be taken into account in the design of steel strengthened structures. In the present work, monotonic and quasi-static cyclic loading were applied to CFRP-to-steel double strap joints for two kinds of CFRP laminates after being aged for a period of 5000 h to evaluate the bond behavior. The bonded joints exposed to salt fog had a different failure mode than that observed in the control specimens (0 h of exposure). The severe reduction of the maximum bond stress resulted from damage initiation that occurred in the corrosion region of the steel substrate, associated with final partial rupture on the corroded steel substrate around the edge of the bonded area: it was also correlated with reduced load carrying capacity. Results of pseudo-cyclic tests showed that the relationship between a local damage parameter (D) and normalized local dissipated energy (Wd/Gf) and the normalized slip increment (ΔS/ΔSult) exhibited almost the same trend in the un-aged and aged bonded joints. The normalized slip increment can be seen as a direct indicator for the local and global damage for the un-aged and aged bonded joints. However, monotonic and quasi-static cyclic tests results revealed that the stress concentration due to local corrosion of steel substrate could lead to brittle rupture or accelerated cumulative damage once the aged bonded interface had become weaker. The bonded joints have exhibited also a smaller relative deformation capacity between CFRP and steel.

Pacheco, João Nuno, Jorge de Brito, Carlos Chastre, and Luís Evangelista. "Statistical analysis of Portuguese ready-mixed concrete production." Construction and Building Materials. 209 (2019): 283-294. AbstractWebsite

This paper evaluates and compares the statistics of compressive strength data from three Portuguese ready-mixed concrete plants. A hierarchical model showed that different groups of concrete strength records are not statistically equivalent, even if they were produced in the same plant and using the same concrete composition. This finding is related to autocorrelation. For the same specified strength class, compositions produced less often result in higher average compressive strength and variability. The statistics of one of the plants were quite different from those of the others, even though the concrete of this plant also complied with the specifications. It was found that the average compressive strength of a mix may be quite dependent on the plant that produced it, even if the compressive strength complies with quality control specifications. Conformity with the target slump and strength class was checked following the conformity criteria of EN 206-1 for continuous production. Nonconformity with slump is more frequent than failure to comply with the strength class. A bias factor for reliability analyses was proposed.

Pacheco, J., J. de Brito, C. Chastre, and L. Evangelista. "Uncertainty models of reinforced concrete beams in bending: code comparison and recycled aggregate incorporation." Journal of Structural Engineering. 145 (2019): 04019013. AbstractWebsite

The bias factor of the Eurocode 2 [CEN (European Committee for Standardization) (2008). Eurocode 2: Design of ConcreteStructures–Part 1-1: General Rules and Rules for Buildings] and ACI 318 [ACI (American Concrete Institute) (2014). Building CodeRequirements for Structural Concrete and Commentary] flexural resistance models of reinforced concrete beams are compared withemphasis on the effect of the incorporation of coarse recycled aggregates sourced from concrete waste. The bias factor of the yielding momentcalculations according to both codes is also investigated, and the bias in the cracking moment when Eurocode 2 material clauses are used. Thedatabase was composed of 174 beams, and the criteria that led to its development are discussed. The effect of recycled aggregate incorporationon the statistical descriptors of the bias factor is evaluated and probabilistic modeling using lognormal distributions is argued for. Preliminarypartial safety factors for the bias factor of recycled aggregate concrete beams are proposed. No significant differences in the bias of theultimate moment were found between the two comparison vectors: Eurocode 2 versus ACI 318 specifications and recycled versus naturalcoarse aggregate. The bias of the cracking moment increased when coarse recycled aggregates were incorporated, most probably due to thehigher heterogeneity of recycled aggregates.

Pacheco, J., J. de Brito, C. Chastre, and L. Evangelista. "Experimental investigation on the variability of the main mechanical properties of concrete produced with coarse recycled concrete aggregates." Construction and Building Materials. 201 (2019): 110-120. AbstractWebsite

Research on the variability of the properties of recycled aggregate concrete is lacking and is necessary for the development of reliability analyses and code calibration procedures. This paper presents an experimental programme on the within-batch variability of the compressive strength, Young’s modulus, and splitting tensile strength of several recycled and natural aggregate concrete mixes. The influence of the recycled concrete aggregates on the mechanical properties and variability of concrete is analysed and discussed and benchmarks with standard predictions for the variability of natural aggregate concrete are made. It was found that full recycled aggregate concrete incorporation did not increase the variability of any of the properties tested, but intermediate ratios of recycled aggregate incorporation did. The properties of high-strength concrete mixes were more variable than that of all other mixes, irrespective of recycled aggregate incorporation. All properties of all compositions were suitably modelled by normal distributions. The coarse recycled aggregates were sourced from concrete waste.

Yang, Yongming, Manuel A. G. Silva, Hugo Biscaia, and Carlos Chastre. "Bond durability of CFRP laminates-to-steel joints subjected to freeze-thaw." Composite Structures. 212 (2019): 243-258. AbstractWebsite

The degradation mechanisms of bonded joints between CFRP laminates and steel substrates under severe environmental conditions require more durability data and studies to increase the database and better understand their causes. Studies on bond properties of double-strap CFRP-to-steel bonded joints with two different composite materials as well as adhesive coupons subjected to freeze-thaw cycles for 10,000 h were conducted to reduce that gap. In addition, the equivalent to the number of thermal cycles and their slips induced in the CFRP laminates was replicated by an equivalent (mechanical) loading-unloading history condition imposed by a static tensile machine. The mechanical properties of the adhesive coupons and the strength capacity of the bonded joints were only slightly changed by the artificial aging. It was confirmed that the interfacial bond strength between CFRP and adhesive is critically related to the maximum shear stress and failure mode. The interfacial bond strength between adhesive and steel degraded with the aging. However, the equivalent thermal cyclic bond stress caused no detectable damage on the bond because only the interfacial elastic regime was actually mobilized, which confirmed that pure thermal cycles aging, per se, at the level imposed, have a low impact on the degradation of CFRP-to-steel bonded joints.

Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Estimations of the debonding process of aged joints through a new analytical method." Composite Structures. 211 (2019): 577-595. AbstractWebsite

The estimation of the long-term durability of adhesively bonded interfaces between Fiber Reinforced Polymers (FRP) and concrete substrates is crucial because degradation potentiates FRP premature debonding. One of the main reasons for mistrusting the use of FRP composites is the premature debonding phenomenon, which, associated to degradation, has been preventing their widespread use. In this research work, an analytical model is proposed that introduces ageing to estimate the effects of degradation of Glass (G) FRP externally bonded to concrete. Cycles were used to experimentally accelerate ageing of beam specimens, namely, (i) salt fog cycles; (ii) wet-dry cycles with salted water; (iii) temperature cycles between −10 °C and +30 °C; and (iv) temperature cycles between +7.5 °C and +47.5 °C. Based on the experimental results obtained and a corresponding bond-slip curve, the analytical model predicts the complete debonding process between FRP composites and a substrate. Consequently, the temporal evolution of the degradation of the bonded interfaces can be calculated and compared with the initial situation prior to exposure. The effects of the environmental conditions are reported and compared.

Gião, Rita, Valter Lúcio, and Carlos Chastre. "Gravity load effects on the behaviour of reinforced concrete beam critical zones subjected to cyclic loads." Engineering Structures. 181 (2019): 503-518. AbstractWebsite

The aim of the present study was to proceed to a numerical analysis of the gravity load effects on the behaviour of reinforced concrete beam critical zones when subjected to cyclic loads. A parametric study to assess the influence of different levels of gravity load on RC beam critical zones subjected to cyclic loading was carried out. For this purpose, assuming the level of gravity load as a variable parameter, a nonlinear numerical model of a beam-column connection, previously calibrated with experimental data, was used. In order to evaluate the gravity load effects in the global response, a numerical study of a RC frame system is also presented. The numerical results are analysed in terms of global hysteretic response, accumulated energy dissipation and equivalent viscous damping ratio. In this numerical study, it was observed that the hysteretic response depends on the load path. In the presence of higher gravity load levels, the structure hysteretic behaviour exhibits higher damage levels, associated to a failure mechanism corresponding to the formation of four span plastic hinges. Thus, the proper test procedure should involve the imposition of a reverse cyclic displacement history starting each cycle from the gravity load effects.

Chaparro, Catarina IP, Liliana R. Loureiro, Manuel Almeida Valente, Paula A. Videira, Joao Paulo Borges, and Paula I. P. Soares. "Application of Hyperthermia for Cancer Treatment: Synthesis and Characterization of Magnetic Nanoparticles and their internalization on Tumor Cell Lines." IEEE, 2019. 1-4. Abstract
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Pardoux, R., A. Fiévet, C. Carreira, C. Brochier-Armanet, O. Valette, Z. Dermoun, B. Py, A. Dolla, S. R. Pauleta, and C. Aubert. "The bacterial MrpORP is a novel Mrp/NBP35 protein involved in iron-sulfur biogenesis." Scientific Reports. 9.1 (2019). AbstractWebsite
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Sanz de Miguel, P., C. Jørgensen, U. Papouschek, L. Osila, Nuno Boavida, and António B. Moniz Deep View: Comparative Report. Preliminary findings: Desk research. Brussels: European Commission, DG EMP, 2019. Abstractcomparativereport_deepview.pdf

This preliminary report presents the outcomes of desk research, which was oriented to obtain a clear picture of the ‘state of the art’ in the involved countries and sectors. The report first reviews the main concepts and categories used to approach the topic and provides a definition of virtual work. Second, it describes the incidence and features of virtual work based on both European and national surveys. Third, it reviews previous research outcomes on the effects of virtual work on working conditions at national and sectoral level. Fourth, it analyses national approach to regulate virtual work. Fifth, the report addresses main institutional features of industrial relations in the three sectors and five countries; and the role played by social dialogue and collective bargaining at sectoral and company level to regulate working conditions of virtual workers.

Raminhos, JS, J. P. Borges, and A. Velhinho. "Development of polymeric anepectic meshes: auxetic metamaterials with negative thermal expansion." 28.4 (2019): 045010. Abstract
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Micaelo, Rui, José Neves, Rui Lopes, and Alexandra Jesus. "A Different Perspective on the Production and Application of Warm Mix Asphalt Under Unfavorable Temperature Conditions." Transportation and Geotechniques: Materials, Sustainability and Climate. Eds. Manik Barman, Musharraf Zaman, and Jia-Ruey Chang. Cham: Springer International Publishing, 2019. 20-32. Abstract

Warm mix asphalt (WMA) is produced by a variety of technologies at lower temperatures that enable to gain important environmental and social benefits and, in consequence, to contribute to a more sustainable transportation infrastructure. The producer usually defines the temperatures used in WMA production. However, some references suggest the increase of temperature in order to allow a longer time to transport or to compact in cases of unfavourable weather conditions, mainly under low temperatures. The objective of this paper is to analyse the feasibility of producing WMA at the same temperatures of hot mix asphalt (HMA) guaranteeing an adequate compaction, and final performance in service. The paper describes a laboratory study to investigate the properties of a WMA using different additives and varying the mixing and compaction temperatures. The effect of production temperatures on the performance of the WMA was evaluated through binder drainage (production phase), volumetric properties (compaction phase), and resistance to permanent deformation (service phase). The paper also presents a numerical study on the time available for paving WMA under unfavourable climatic conditions. Results demonstrated that it is possible to produce WMA at high temperatures without problems of binder drainage, during transport, and of performance in service if adequate compaction is achieved. In fact, the production temperatures influenced the compaction phase. However, it is possible to increase the temperature without negatively affecting the required volumetric properties. The rut depth of the permanent deformation test was mostly influenced by the air-voids of the compacted WMA and the binder. From the numerical study, it was concluded that the time available for in situ compaction increased substantially when WMA was paved at higher temperature. However, in cases of low air temperature and thin layer, the increase of temperature may not be sufficient to obtain the desired level of density or air-voids.

Cordas, C. M., M. Campaniço, R. Baptista, L. B. Maia, I. Moura, and JJG Moura. "Direct electrochemical reduction of carbon dioxide by a molybdenum-containing formate dehydrogenase." Journal of Inorganic Biochemistry. 196 (2019). AbstractWebsite
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Gomes, F. O., L. B. Maia, C. Cordas, I. Moura, C. Delerue-Matos, JJG Moura, and S. Morais. "Electroanalytical characterization of the direct Marinobacter hydrocarbonoclasticus nitric oxide reductase-catalysed nitric oxide and dioxygen reduction." Bioelectrochemistry. 125 (2019): 8-14. AbstractWebsite
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