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Faraday waves are described, under appropriate conditions, by a damped nonlocal parametrically driven nonlinear Schro¨dinger equation. As the strength of the applied forcing increases this equation undergoes a sequence of transitions to chaotic dynamics. The origin of these transitions is explained using a careful study of a two-mode Galerkin truncation and linked to the presence of heteroclinic connections between the trivial state and spatially periodic standing waves. These connections are associated with cascades of gluing and symmetry-switching bifurcations; such bifurcations are located in the partial differential equations as well. [Copyright &y& Elsevier]

• Efficient tool for postprocessing steady thermographic data for structural health monitoring. • New iterative method based on topological sensitivity computations. • Impressive reconstructions in very challenging scenarios where the size of the defects is very small and thermograms are highly noisy. This paper deals with the use of steady active thermographic inspection as a structural health monitoring method to detect defects and inclusions in a heat conductive medium. The proposed postprocessing method has the advantage of taking into account the whole physics of the problem instead of a reduced set of physical information, as most of the traditional methods do. In comparison with other non-destructive testing techniques like ultrasonics, thermographic inspection is non-contact, more non-intrusive, and safer. However, processing thermographic data is a fairly demanding problem because heat conduction is short range and exhibits a poor signal-to-noise ratio. Numerical experiments illustrate that the present postprocessing technique detects damage fairly well even in very challenging scenarios where the size of the defects is rather small and/or thermograms are highly noisy. [ABSTRACT FROM AUTHOR]

Efficient and precise optimisation methodologies, when applied to improve the real performance of engineering devices, must balance the need to reduce high computational cost and maintain accuracy in the treatment of first principles and physicochemical properties. This is the aim of the time– and parameter–adaptive model order reduction technique presented in this article. In contrast to (standard) pre–processed reduced order models (ROMs), the proposed adaptive strategy presents two principal advantages: (i) it does not require any previous information to derive an accurate ROM, which provides a substantial acceleration of solution calculations, and (ii) the periods of full order model calculations can be further reduced when information needed by the optimisation algorithms to derive ROM updates is provided by the previous simulations. Its implementation within the framework of efficient gradient–like optimisation methods requires a careful analysis of the sensitivities computation in order to resolve certain issues inherent to adaptive ROMs. The proposed technique is applied to the optimisation of the performance of a three–dimensional lithium–ion cell described by the electrochemical pseudo–four–dimensional battery model (p4D model). In particular, the results obtained when maximising the energy delivered by a graphite–NMC811 cell and a graphite–LFP cell demonstrate the robustness and efficacy of the method. The presented methodology has been implemented in a software tool named OptiBat, developed in the framework of a H2020 project, and available in the project website https://defacto-project.eu/defacto-rom-optimisation-tool/. [ABSTRACT FROM AUTHOR]

The influence of dietary protein source (fishmeal, soy-protein concentrate and soy-protein concentrate supplemented with methionine) on voluntary feed intake, daily feeding rhythm and nutritive utilisation of diet was studied in the gilthead sea bream (Sparus aurata) fed by hand or demand feeding. Fish weighing 21 g were maintained indoors under natural conditions of temperature and photoperiod (transparent ceiling) and allowed ad libitum or self-feeding of experimental diets for 26 days, with three replicates per treatment. In the first experiment, the influence of hand or demand feeding on growth rate and feed utilisation of a fishmeal-based control diet was studied. In a second trial, involving different protein sources, fish were maintained under the experimental conditions for 6 days after 20 days training. The general composition of the experimental diets was: 45% protein, 14% lipids and 20% carbohydrates. Results showed that: (1) gilthead sea bream preferentially feed in the afternoon and evening; (2) demand feeding improved both food conversion and protein efficiency; (3) the protein source appeared to induce changes in the timing of feeding; and (4) supplements of methionine advanced the time of feeding and lengthened ingestion phases. [Copyright &y& Elsevier]