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2019
Fernandes, Cláudio A., Alexei Yu. Karlovich, and Yuri I. Karlovich. "Noncompactness of Fourier convolution operators on Banach function spaces." Annals of Functional Analysis. 10.4 (2019): 553-561.
Mateus, Octávio, Pedro M. Callapez, Michael J. Polcyn, Anne S. Schulp, António Olímpio Gonçalves, and Louis L. Jacobs. "O registo fóssil da biodiversidade em Angola ao longo do tempo: uma perspectiva paleontológica." Biodiversidade de Angola: Ciência e Conservação - Uma Síntese Moderna. Eds. Huntley B.J., Russo V., Lages F., and Ferrand N. Porto: Arte & Ciência, 2019. 89-116. Abstractmateus_et_al_2019_paleobiodiversidade_angola.pdf

Este capítulo apresenta uma visão geral da paleobiodiversidade alfa de Angola com base no registo fóssil disponível, o qual se limita às rochas sedimentares, a sua idade variando entre o Pré‑Câmbrico e o pre‑
sente. O período geológico com a maior paleobiodiversidade no registo fóssil angolano é o Cretácico, com mais de 80% do total dos táxones fósseis conhecidos, especialmente moluscos marinhos, sendo estes na sua maioria
amonites. Os vertebrados representam cerca de 15% da fauna conhecida e cerca de um décimo destes são espécies descritas pela primeira vez com base em espécimes de Angola.

Fernandes, Vítor H., J. Koppitz, and T. Musunthia. "The rank of the semigroup of all order-preserving transformations on a finite fence." Bulletin of the Malaysian Mathematical Sciences Society (DOI: 10.1007/s40840-017-0598-1). 42.5 (2019): 2191-2211. AbstractWebsite

A zig-zag (or fence) order is a special partial order on a (finite) set. In this paper, we consider the semigroup $TF_{n}$ of all
order-preserving transformations on an $n$-element zig-zag ordered set. We determine the rank of $TF_{n}$ and provide a minimal generating set for $TF_{n}$. Moreover, a formula for the number of idempotents in $TF_{n}$ is given.

Ferrás, L. L., M. L. Morgado, M. Rebelo, R. T. Leiva, A. Castelo, G. H. Mckinley, and A. M. Afonso. "Recent Advances in Complex Fluids Modeling." Fluid Flow Problems. 2019.
Almeida, André, António Ramos, Rui Marreiros, Válter Lúcio, and Ricardo Faria. "Resposta da ligação pilar-laje fungiforme sujeitas a ações horizontais cíclicas reforçadas com estribos." Revista Portuguesa de Engenharia de Estruturas. Série III.9 (2019): 67-74.
Amarante dos Santos, Filipe, Gianmario Benzoni, and Fernando Fraternali. "Seismic Performance of Superelastic Tensegrity Braces." Ingegneria Sismica - International Journal of Earthquake Engineering. vol. 3 (2019).
Ribau, A. M., L. Ferrás, M. L. Morgado, M. Rebelo, and A. Afonso. "Semi-Analytical Solutions for the Poiseuille-Couette Flow of a Generalised Phan-Thien-Tanner Fluid." Fluids . 2.3 (2019).
F. Queda, G.Covas, Silva A.Santos R.Bronze Javier Cañada Filipe Manuel Marques T. C. M. F. "A top-down chemo-enzymatic approach towards N-acetylglucosamine-N-acetylmuramic oligosaccharides: Chitosan as a reliable template." Carbohydr. Polym.. 224 (2019): 115133.
Mulenga, A., M. Faias, P. Mota, and J. P. Pina. "What happens when the stock markets are closed?" Electronic Journal of Applied Statistical Analysis. 12.2 (2019): 405-415. AbstractWebsite

The normality of the log-return of stock prices is often assumed by the market players in order to use some useful results, as for instance, the Black-Scholes formula for pricing European options. However, several studies regarding different indexes have shown that the normality assumption of the returns usually fails.
In this paper we analyse the normality assumption for intra-day and inter-day log-returns, comparing opening prices and/or closing prices for a large number of companies quoted in the Nasdaq Composite index. We use the Pearson's Chi-Square, Kolmogorov-Smirnov, Anderson-Darling, Shapiro-Wilks and Jarque-Bera goodness-of-fit tests to study the normality assumption.
We find that the failure rate in the normality assumption for the log-return of stock prices is not the same for intra-day and inter-day prices, is somewhat test dependent and strongly dependent on some extreme price observations.
To the best of our knowledge, this is the first study on the normality assumption for the log-return of stock prices dealing simultaneously with a large number of companies and normality tests, and at the same time considering various scenarios of intra-day, inter-day prices and data trimming.

Bedon, C., M. Arrigoni, F. Santos, and L. Figuli. "Advancements in design and analysis of protective structures 2019." Advances in Civil Engineering. 2019 (2019). AbstractWebsite
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Gouveia, Nuno D., Duarte M. V. Faria, and António Pinho Ramos. "Assessment of SFRC flat slab punching behaviour – part I: monotonic vertical loading." Magazine of Concrete Research. 71 (2019): 587-598. AbstractWebsite

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 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 behaviour and inverse analysis. The inverse analysis made it possible to define the stress–crack opening relationship that characterises 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.

Gouveia, Nuno D., Duarte M. V. Faria, and António Pinho Ramos. "Assessment of SFRC flat slab punching behaviour – part II: reversed horizontal cyclic loading." Magazine of Concrete Research. 71 (2019): 26-42. AbstractWebsite

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.

Teubig, P., P. Remmels, P. Klenze, H. Alvarez-Pol, E. Alves, J. M. Boillos, P. Cabanelas, R. C. da Silva, D. Cortina-Gil, J. Cruz, D. Ferreira, M. Fonseca, D. Galaviz, E. Galiana, R. Gernhäuser, D. González, A. Henriques, A. P. Jesus, H. Luís, J. Machado, L. Peralta, J. Rocha, A. M. Sánchez-Benítez, H. Silva, and P. Velho. "Challenging the Calorimeter CALIFA for FAIR Using High Energetic Photons." Eds. José-Enrique García-Ramos, María V. Andrés, José Lay A. Valera, Antonio M. Moro, and Francisco Pérez-Bernal. Cham: Basic Concepts in Nuclear Physics: Theory, Experiments and Applications, 2019. 245-246. Abstract
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Ambrosi, Elia, Philip Bartlett, Alexandra I. Berg, Stefano Brivio, Geoffrey Burr, Sweety Deswal, Jonas Deuermeier, Masa-aki Haga, Asal Kiazadeh, Gabriela Kissling, Michael Kozicki, Cina Foroutan-Nejad, Ella Gale, Yago Gonzalez-Velo, Anouk Goossens, Ludovic Goux, Tsuyoshi Hasegawa, Hans Hilgenkamp, Ruomeng Huang, Sherif Ibrahim, Daniele Ielmini, Anthony J. Kenyon, Vladimir Kolosov, Yang Li, Sayani Majumdar, Gianluca Milano, Themis Prodromakis, Niloufar Raeishosseini, Vikas Rana, Carlo Ricciardi, Monica Santamaria, Alexander Shluger, Ilia Valov, Rainer Waser, Stanley R. Williams, Dirk Wouters, Yuchao Yang, and Andrea Zaffora. "Electrochemical metallization {ReRAMs} ({ECM}) - Experiments and modelling: general discussion." Faraday Discussions. 213 (2019): 115-150. AbstractWebsite
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Mateus, Octávio, Pedro M. Callapez, Michael J. Polcyn, Anne S. Schulp, António Olímpio Gonçalves, and Louis L. Jacobs. "The Fossil Record of Biodiversity in Angola Through Time: A Paleontological Perspective." Biodiversity of Angola: Science {&} Conservation: A Modern Synthesis. Eds. Brian J. Huntley, Vladimir Russo, Fernanda Lages, and Nuno Ferrand. Cham: Springer International Publishing, 2019. 53-76. Abstract

This chapter provides an overview of the alpha paleobiodiversity of Angola based on the available fossil record that is limited to the sedimentary rocks, ranging in age from Precambrian to the present. The geological period with the highest paleobiodiversity in the Angolan fossil record is the Cretaceous, with more than 80{%} of the total known fossil taxa, especially marine molluscs, including ammonites as a majority among them. The vertebrates represent about 15{%} of the known fauna and about one tenth of them are species firstly described based on specimens from Angola.

Amado, J., L. Freire, and F. A. D. Santos. "Framework for the management of a large stock of earth retaining structures." IABSE Symposium, Guimaraes 2019: Towards a Resilient Built Environment Risk and Asset Management - Report. 2019. 780-787. Abstract
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Torres, Marta, João C. Freitas, and Mónica Mesquita. "Literacy in {Schools}: a {Virtual} {Museum} for the {Dissemination} of the {Cultural} {Heritage} of {Fishing} {Communities}." {ICERI2020} {Proceedings}. Granada: Fundación General UGR-Empresa y Universidad de Granada, 2019. Abstract
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Fraternali, F., and F. Santos. "Mechanical modeling of superelastic tensegrity braces for earthquake-proof structures." Extreme Mechanics Letters. 33 (2019). AbstractWebsite
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Deuermeier, J., A. Kiazadeh, A. Klein, R. Martins, and E. Fortunato. "Multi-level cell properties of a bilayer Cu2O/Al2O3 resistive switching device." Nanomaterials. 9 (2019). Abstract
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Ménesguen, Y., {M. C. } Lépy, Y. Ito, M. Yamashita, S. Fukushima, M. Polasik, K. Słabkowska, Syrocki, E. Wȩder, P. Indelicato, {J. P. } Marques, {J. M. } Sampaio, M. Guerra, F. Parente, and {J. P. } Santos. "Precise x-ray energies of gadolinium determined by a combined experimental and theoretical approach." Journal Of Quantitative Spectroscopy & Radiative Transfer. 236 (2019). Abstract

We combined different experimental techniques with a theoretical approach to determine a consistent set of diagram lines energies and binding energies. We propose an original approach consisting in determining the mass attenuation coefficients in an energy range covering the L-, M- and N- absorption edges, including a detailed evaluation of the associated uncertainties, to derive precisely the binding energies. We investigated the Lα, Lβ and M spectra of Gd with an independantly calibrated high-resolution anti-parallel double-crystal x-ray spectrometer. All the lines were identified and found in excellent agreement with the binding energies previously derived. Morever, we identified for the first time M5−O2, M4−O2,3 and M4−N2,3 diagram lines.

Santos, F., G. Benzoni, and F. Fraternali. "Seismic performance of superelastic tensegrity braces." Ingegneria Sismica. 36 (2019): 20-37. AbstractWebsite
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Torres, Marta, João Freitas, and Mônica Mesquita. "T.{H}.{E}. {Tecnologia}-{História} e {Educação}: conceção de um museu virtual enquanto estratégia de valorização de património cultural piscatório." Atas do {III} {Enjie} – {Encontro} {Nacional} de {Jovens} {Investigadores} em {Educação}. Universidade Lusófona de Humanidades e Tecnologias, 2019. 621-631. Abstract

Este projeto é delineado no contexto do Observatório de Literacia Oceânica – espaço de investigação transdisciplinar e transcultural. O seu objeto de estudo são diferentes comunidades costeiras urbanas, localizadas na área entre a Costa da Caparica e a Fonte da Telha. As comunidades piscatórias, situadas nessas áreas costeiras urbanas são social, económica, cultural e intelectualmente invisíveis. Numa perspetiva de educação intercultural e de inovação educativa, em ambientes tecnologicamente enriquecidos, que possibilitem a comunicação em rede, pretende-se desenvolver a co-construção de um museu virtual sobre as Artes da Pesca locais, sustentada em conceitos e conteúdos da disciplina de História. Pretende-se compreender de que forma se realizam as interações entre saber formal e informal, utilizando instrumentos e ambientes digitais, e como se poderá melhorar o desempenho das comunidades estudantis piscatórias. Os participantes neste projeto pertencem às comunidades piscatórias da área acima descrita e são estudantes de escolas da região da Caparica. Fazendo uso da etnografia crítica, num ambiente educacional formal e tecnologicamente enriquecido, pretende-se fomentar interações entre saberes formais e informais. A construção da plataforma digital e a construção e aplicação de instrumentos, resultando num museu virtual, servir-se-ão da metodologia Design-based Research.

Rovisco, Ana, Rita Branquinho, Jorge Martins, Elvira Fortunato, Rodrigo Martins, and Pedro Barquinha. "{Growth Mechanism of Seed-Layer Free ZnSnO3 Nanowires: Effect of Physical Parameters}." Nanomaterials. 9 (2019): 1002. Abstract

ZnSnO3 semiconductor nanostructures have several applications as photocatalysis, gas sensors, and energy harvesting. However, due to its multicomponent nature, the synthesis is far more complex than its binary counter parts. The complexity increases even more when aiming for low-cost and low-temperature processes as in hydrothermal methods. Knowing in detail the influence of all the parameters involved in these processes is imperative, in order to properly control the synthesis to achieve the desired final product. Thus, this paper presents a study of the influence of the physical parameters involved in the hydrothermal synthesis of ZnSnO3 nanowires, namely volume, reaction time, and process temperature. Based on this study a growth mechanism for the complex Zn:Sn:O system is proposed. Two zinc precursors, zinc chloride and zinc acetate, were studied, showing that although the growth mechanism is inherent to the material itself, the chemical reactions for different conditions need to be considered.

Freitas, João Correia, Fernando Egídio Reis, Vítor Godinho Lopes, and David Costa. "A {Khan} {Academy} em {Portugal}, o ensino e aprendizagem da {Matemática} e a {Formação} de {Professores} - um contributo da {EDUCOM}." Educação e Matemática (2019): 5. Abstract
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Sanchez-Sobrado, Olalla, Manuel J. Mendes, Sirazul Haque, T. Mateus, H. Aguas, E. Fortunato, and R. Martins. "{Lightwave trapping in thin film solar cells with improved photonic-structured front contacts}." J. Mater. Chem. C. 7 (2019): 6456-6464. Abstract
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