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2019
Romba, Luis, and Stan Valtchev. "Efficiency Improvement in Wireless Power System." Emerging Capabilities and Applications of Wireless Power Transfer. IGI Global, 2019. 23-48. Abstract

This chapter focuses on mid-range wireless power transfer (WPT) systems applied to electric vehicle (EV) battery chargers. The WPT is recently considered as an efficient electric energy transfer process between two or more points in space, without wiring. The technology associated with each specific process of WPT differs from case to case depending on the distance between those points and the power to be transferred between them. The widely adopted distance categories are named short-range, mid-range, and long-range. The short-range is normally defined as up to a few millimeters range. The mid-range is between a few millimeters and a few meters. The long-range distance is defined as a longer than that of the previous category, stretching up to a few kilometers.

Baikova, {Elena N. }, Luis Romba, and Stan Valtchev. "Electromagnetic Influence of WPT on Human's Health: Modelling, Simulation, and Measurement." Emerging Capabilities and Applications of Wireless Power Transfer. IGI Global, 2019. 141-161. Abstract

The focus of this chapter is the electromagnetic interference (EMI) and the electromagnetic compatibility (EMC) that the wireless power transfer (WPT) systems reveal as problems. The wireless power transfer (WPT) was introduced by Nikola Tesla more than one hundred years ago, and only recently it attracted the attention of specialists, due to the improved technical means. The WPT technology now has many applications, especially for charging of various electronic devices (i.e., mobile phones, laptops, implants, and home appliances), informatics, and electronics equipment. The high-power equipment and installations (e.g., intelligent machining systems, robots, forklift trucks, and electric cars) are also getting wireless. Moreover, much attention has been focused on the electric transportation system for improving the safe and convenient charging of electric vehicle (EV) batteries.

Meshcheryakov, V. N., D. V. Lastochkin, Z. M. Shakurova, and S. Valtchev. "Energy saving system of cascade variable frequency induction electric drive." E3S Web of Conferences. 124 (2019). Abstract
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Cabrita, {M. R. }, V. Cruz-Machado, and S. Duarte. "Enhancing the Benefits of Industry 4.0 from Intellectual Capital: A Theoretical Approach." ICMSEM 2018: Proceedings of the Twelfth International Conference on Management Science and Engineering Management. Eds. {Jiuping } Xu, {Fang Lee } Cooke, {Mitsuo } Gen, and {Syed Ejaz } Ahmed. Lecture Notes on Multidisciplinary Industrial Engineering. Springer, 2019. 1581-1591. Abstract

Our world is facing substantial economic and social challenges due to an increasing pace of technological developments. The introduction of the Internet of Things (IoT) is ushering in a fourth industrial revolution. The vision of Industry 4.0 describes a whole new approach to business operations, and especially the production industries which is characterized by a new level of socio-technical interaction. Emphasizing the importance of intangibles management, organizations have become increasingly focused on the Intellectual Capital (IC) as the main source of value creation. From a strategic point of view, IC is linked to the ability to create and apply the potential of an organizations knowledge based capabilities, and is commonly categorized into three main components: human, structural and relational capital. The industry 4.0 is changing the way we create value which requires from organizations and individuals a rethinking of what is expected or desired from the internet-connected devices. As a phenomenon of interactions and complementarities, IC can offer a possible pathway for reconfiguring business models. The contribution of this work is mainly conceptual. The aim of this paper is to explore what has been researched so far about the importance of industry 4.0 with impact in organizational value creation and how the theory of intellectual capital can help to leverage its benefits. To achieve this objective, a comprehensive review of journal articles, conference papers, books and international reports was performed

Biscaia, H. C., C. Chastre, and M. 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. © 2018 Elsevier Ltd

Rebelo, H. B., F. Amarante dos Santos, C. Cismaşiu, and D. Santos. "Exploratory study on geodesic domes under blast loads." International Journal of Protective Structures. 10 (2019): 439-456. AbstractWebsite
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2018
Faria, Ricardo, Rui Marreiros, António Ramos, and Gonçalo Antunes. "Efeito do confinamento e da redistribuição de momentos no comportamento de lajes fungiformes." Encontro Nacional Betão Estrutural 2018. LNEC, Lisboa: GPBE, 2018.
Baikova, {E. N. }, L. Romba, {S. S. } Valtchev, R. Melicio, V. {Fernão Pires}, A. Krusteva, and G. Gigov. "Electromagnetic field generated by a wireless energy transfer system: comparison of simulation to measurement." Journal of Electromagnetic Waves and Applications. 32 (2018): 554-571. Abstract

This paper presents a wireless energy transfer system operating at the frequency values of kHz order: modeling, simulation, and comparison with prototype measurement results. Wireless energy transfer system model using finite element method was carried out to simulate the electric field and the magnetic flux density for different air gap sizes between the transmitter and the receiver coils. Results are presented and compared with the electromagnetic emission measurements radiated by the wireless energy transfer system prototype. The electric field comparison between the simulated and the prototype measurement values shows an error of roughly 8.7{%}. In the recent years, the interest in the wireless energy transfer technology, especially for electric vehicles batteries charging, is rapidly increasing. As a result of the increasing application of this technology in the industrial and consumer electronic products, more concerns are raised about the electromagnetic compatibility, since the wireless energy transfer systems produce electromagnetic emissions in the surrounding environment.

Matos, Ricardo JR, Catarina IP Chaparro, Jorge C. Silva, Manuel Almeida Valente, João Paulo Borges, and Paula I. P. Soares. "Electrospun composite cellulose acetate/iron oxide nanoparticles non-woven membranes for magnetic hyperthermia applications." (2018). Abstract
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Khili, Faouzia, Joao Borges, Pedro L. Almeida, Rabah Boukherroub, and Amel Dakhlaoui Omrani. "Extraction of cellulose nanocrystals with structure I and II and their applications for reduction of graphene oxide and nanocomposite elaboration." (2018): 1-15. Abstract
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Mudrov, Mikhail, Anatoliy Ziuzev, Konstantin Nesterov, and Stanimir Valtchev. "Electric Drives Power-Hardware-in-the-Loop System Structures." 2018 20th European Conference on Power Electronics and Applications, EPE 2018 ECCE Europe. United States: Institute of Electrical and Electronics Engineers Inc., 2018. Abstract

Power-Hardware-in-the-Loop (PHiL) system for electric drives application based on power converter with Field Programmable Gate Array (FPGA)-based control system is discussed. PHiL structures are under discussion as well. During the PHiL mathematical model analysis instantaneous current repeating quality is increased. Variable frequency drive (VFD) was selected for testing.

Rebelo, H. B., A. Gregório, P. A. R. Rosa, D. Lecompte, and C. Cismaşiu. "Experimental characterization of 3D-printed PLA under uniaxial high strain-rate loading." AuxDefense 2018 – 1st World Conference on Advanced Materials for Defense. Lisbon 2018. auxdefense_extabstract_v2.pdf
Acosta-Vargas, P., Esparza, D., Rybarczyk, Y., González, M., Villarreal, S., Jadán, J., Guevara, C., Sanchez-Gordon, S., Calle-Jimenez, T., Baldeón, J., and Nunes I. "Educational resources accessible on the tele-rehabilitation platform." 9th International Conference on Applied Human Factors and Ergonomics. Orlando, USA 2018.
Rybarczyk, Y. "Educative game to promote phonological awareness in children with neurodevelopmental disorders." IEEE Latin America Transactions. 16.1 (2018): 242-247.copy.pdf
Silva, Manuel A. G., Fernando F. S. Pinho, and Miguel Estevão. "Effects of sodium chloride and sulfate on GFRP bars." ACI Structural and Materials Journals. 115 .DOI: 10.14359/51701922 (2018).
Martinho, H., and H. Rocha. "A escrita matemática e a intuição em Geometria [Mathematical writting and intuition in geometry]." Educação e Matemática. 149-150 (2018): 34-38.Website
Rybarczyk, Y., and Kleine Deters J. "Evaluation of self-rehabilitation movements by Hidden Markov Model." IEEE International Conference on INnovations in Intelligent SysTems and Applications. Thessaloniki, Greece 2018.
"Experimental analysis of rubble stone masonry walls strengthened by transverse confinement under compression and compression-shear loadings." International Journal of Architectural Heritage. 12.DOI: 10.1080/15583058.2017.1377314 (2018): 91-113.
Gouveia, Nuno D., Massimo Lapi, Maurizio Orlando, Duarte M. V. Faria, and António M. P. Ramos. "Experimental and theoretical evaluation of punching strength of steel fiber reinforced concrete slabs." Structural Concrete. 19.1 (2018): 217-229. AbstractWebsite

This paper deals with the experimental and theoretical evaluation of punching shear capacity of steel fiber reinforced concrete (SFRC) slab–column connections. Five experimental specimens with a thickness of 160 mm, different fiber volume contents (0, 1.0, and 1.5%) and different flexural reinforcement ratios (0.75 and 1.5%) have been tested. The experimental results were evaluated using a physical–mechanical model based on the critical shear crack theory (CSCT). The model has given a good approximation of experimental punching shear strengths. In general, tests have highlighted a significant increase in load and deformation capacity of fiber reinforced concrete slab–column connections in comparison with reinforced concrete connections.

Caeiro, Frederico, and Ayana Mateus. "Empirical Power Study of the Jackson Exponentiality Test." Demography and Health Issues. Springer International Publishing, 2018. 225-235. Abstract
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Reynders, G., R. Amaral Lopes, A. Marszal-Pomianowska, D. Aelenei, J. Martins, and D. Saelens. "Energy flexible buildings: An evaluation of definitions and quantification methodologies applied to thermal storage." Energy and Buildings. 166 (2018): 372-390. AbstractWebsite
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Mateus, Ayana, and Frederico Caeiro. "Exact and Approximate Probabilities for the Null Distribution of Bartels Randomness Test." Contributions to Statistics. Springer International Publishing, 2018. 227-240. Abstract
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Franco, N., H. Biscaia, and C. Chastre. "Experimental and numerical analyses of flexurally-strengthened concrete T-beams with stainless steel." Engineering Structures. 172 (2018): 981-996. AbstractWebsite

This work presents the results and the main conclusions of a series of experimental tests carried out to evaluate the efficiency of post-installed stainless steel reinforcement on the flexural strengthening of Reinforced Concrete (RC) T-beams when the bonding techniques EBR (Externally Bonded Reinforcement), NSM (Near Surface Mounted) and MA-EBR (EBR with Mechanical Anchors) are used. The RC T-beams were also modelled using a commercial Finite Element (FE) software in order to predict their behaviour until the rupture. For this purpose, a set of single-lap shear tests were also carried out to evaluate the local bond-slip relationships developed within the Stainless Steel (SS)-to-concrete interface. Due to the experimental bond-slip relationships, the numerical simulations were able to predict, with good accuracy, the different behaviours of the RC T-beams until their rupture. Moreover, the different rupture modes observed on all the RC T-beams herein tested were very well estimated by the numerical analyses. The tests of the RC T-beams showed that all the strengthening techniques allowed their flexural stiffness to be increased. Nevertheless, the RC T–beams strengthened with the EBR and NSM techniques had premature ruptures, i.e. the rupture in the RC T-beams occurred even before the yielding of their steel reinforcements. The RC T-beam strengthened with the MA-EBR technique showed good ductility and the highest load bearing capacity, which means that the MA-EBR technique is the best bonding technique herein used. © 2018 Elsevier Ltd

Pereira, L., A. C. Freire, M. Sá da Costa, V. Antunes, L. Quaresma, and R. Micaelo. "Experimental study of the effect of filler on the ductility of filler-bitumen mastics." Construction and Building Materials. 189 (2018): 1045-1053. AbstractWebsite
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Viegas, J. C., F. Oliveira, and D. Aelenei. "Experimental study on the aerodynamic sealing of air curtains." Fluids. 3 (2018). AbstractWebsite
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