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Photocatalytic Performance of HKUST–1/TiO2 Composite towards Hydrogen Generation,
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Porous Composite Nanomaterials based on MOFs for Green Hydrogen Production by Photocatalysis,
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Photocatalytic Performance of HKUST–1/TiO2 Composite towards Hydrogen Generation
No full textInternational audienc
Reflective Practice In STEM Degrees to Support Adaptability and Lifelong Learning
No full textInternational audienceThe benefits and importance of reflective learning is widely recognized for the development of STEM students. However, the implementation of reflective practices in the curriculum remains a significant challenge for educators. The main purpose of this paper is to help educators overcome this challenge: to better support students to develop their approaches to reflective learning, to better develop ownership of their own learning processes and to foster skills to support lifelong learning. First, we describe the results of a recent survey among engineering academics to look at the issue of reflective learning and the extent to which it is deployed in practice. This was then followed up with a linked workshop designed for STEM educators to exchange experiences on their reflective learning practices at SEFI 2023 conference at TU Dublin in September 2023. The outcomes of both survey and workshop showed a genuine positivity and consciousness of the need and benefits towards the implementation of student reflective practice with a range of approaches used to guide to the students in this. Despite the numerous identified hurdles of implementation, we propose interesting practices to make the implementation easier
In-situ characterization of Soil Structure Interaction through measurement of Impedance Functions
No full textInternational audienceIn situ characterization of structural behaviour under seismic hazard provides an opportunity to acquire experimental data that improve our understanding of soil-structure interaction (SSI). Experimental programs such as Lotung and Hualien in Taiwan, EuroProteas in Greece and NUPEC in Japan, are amongst the most known. Such investigations aim at studying a structure with a rigid shallow raft and measuring the seismic impedance functions at soil-foundation interface. Indeed, impedance functions are by far the most widely used tools to study SSI. In this paper, considering feedbacks from these in situ tests, we aim at assessing the feasibility to acquire measurements of the seismic impedance functions for any structure with a rigid shallow foundation. To test the proposed methodology, we carry out a laboratory test with a small-scale device: the soil is represented by a model material (silicon rubber block) and the foundation by a cylindrical shaker inducing monitored harmonic vertical forces on the silicon rubber block. Experimental tests are paired with numerical simulations to identify, by inverse analysis, unknown parameters and to compute the order of magnitude of displacements and forces within the system. This paper presents the laboratory test setup, the experimental design, and the results of the associated simulations
Wideband Spectrum Sensing Using Modulated Wideband Converter and Data Reduction Invariant Algorithms
No full textInternational audienceWideband spectrum sensing is a challenging problem in the framework of cognitive radio and spectrum surveillance, mainly because of the high sampling rates required by standard approaches. In this paper, a compressed sensing approach was considered to solve this problem, relying on a sub-Nyquist or Xsampling scheme, known as a modulated wideband converter. First, the data reduction at its output is performed in order to enable a highly effective processing scheme for spectrum reconstruction. The impact of this data transformation on the behavior of the most popular sparse reconstruction algorithms is then analyzed. A new mathematical approach is proposed to demonstrate that greedy reconstruction algorithms, such as Orthogonal Matching Pursuit, are invariant with respect to the proposed data reduction. Relying on the same formalism, a data reduction invariant version of the LASSO (least absolute shrinkage and selection operator) reconstruction algorithm was also introduced. It is finally demonstrated that the proposed algorithm provides good reconstruction results in a wideband spectrum sensing scenario, using both synthetic and measured data
Cross-cultural evaluation of a web application to support communication and collaboration among stakeholders of the school inclusion of children with ASD
No full textInternational audienceThe schooling of children with autism spectrum disorder is a challenge that relies on all stakeholders (families, schools, and medical-social professionals). In many countries, the Individualized Education Plan (IEP) is a monitoring tool of the schooling process, implemented by the aforementioned stakeholders, but they face several barriers to the co-education process. The CoEd web app was designed using participatory methods in France, with interactive services for the children's follow-up and the three-way collaboration. CoEd applicability was assessed in Belgian cultural context (Walloon territory), as they experiences similar issues.The results showed comparable results between the two countries. The Belgian audience appreciated CoEd and would be ready to use it in real conditions, as is currently the case in France. Thus, this participatory design work developed a tool that meets the needs expressed by the French participants and those of stakeholders beyond French borders.La scolarisation des enfants atteints de troubles du spectre autistique est un défi qui repose sur l'ensemble des acteurs (familles, écoles et professionnels médico-sociaux). Dans de nombreux pays, le plan d'éducation individualisé (PEI) est un outil de suivi du processus de scolarisation, mis en œuvre par les parties prenantes susmentionnées, mais celles-ci se heurtent à plusieurs obstacles dans le processus de coéducation. L'application web CoEd a été conçue en utilisant des méthodes participatives en France, avec des services interactifs pour le suivi des enfants et la collaboration tripartite. L'applicabilité de CoEd a été évaluée dans le contexte culturel belge (territoire wallon), étant donné que les deux pays connaissent des problèmes similaires. Le public belge a apprécié CoEd et serait prêt à l'utiliser dans des conditions réelles, comme c'est actuellement le cas en France. Ainsi, ce travail de conception participative a permis de développer un outil qui répond aux besoins exprimés par les participants français et à ceux des acteurs au-delà des frontières françaises.Traduit avec www.DeepL.com/Translator (version gratuite
A probabilistic study on seismic induced accumulated plastic strain
No full textInternational audienceA linearization method based on the work of Nguyen [Analyse systématique du concept de comportement linéaire équivalent en ingénierie sismique, PhD., université Paris-Est; EDF; ESTP, Cachan (2017)] is extended in this paper. The method is based on the fitting of the relative acceleration transfer function of a linear SDOF oscillator on non-linear relative acceleration transfer functions to obtain the equivalent dynamic parameters in terms of frequency and viscous damping ratio. This paper proposes formulas for the fitting and introduces an additional parameter in the non-linear transfer function numerical calculation. Elastic perfectly plastic, linear kinematic hardening and non-linear kinematic hardening materials behaviors are considered. The cases of wide and narrow band input motions are explored. The linearization method results are compared to formulas from the literature and evaluated according to goodness of fit criteria. The method gives good results regarding relative speed and acceleration values and less accurate results regarding the maximum displacement prediction. This method should be considered in the case of the determination of transferred motions and fatigue analysis
Influence of thermal diffusion on thermoelastic coupling and dissipated energy fields evaluated in the heterogeneous case of a woven composite
No full textInternational audienceThis article investigates the effects of thermal diffusion on the evaluation of thermoelastic coupling and dissipated energy fields from infrared measurements. The experimental fields are obtained using the heat build-up protocol applied to a 3D layer-to-layer woven composite. A finite element model based on micro-computed tomography results of the tested specimen was generated for the purpose of simulation/experiment comparisons. Two types of finite element simulations are carried out: mechanical and thermal. The analyses of the numerical and experimental results allow to highlight that the heat conduction inside the investigated specimen has a measurable effect on the thermoelastic coupling and dissipated energy fields. The interpretation of the experimental results obtained at the mesoscale level should therefore be accompanied by analyses of numerical simulations that include diffusion effects. On the other hand, macroscale simulation/experiment comparisons showed that, in the investigated configuration, the diffusion has a negligible effect on the global values averaged over the side face of the tested specimen