HAL-Université de Bretagne Occidentale
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Impact of Adaptive Feedback on Learning Programming with a Serious Game in High Schools' Classes
No full textInternational audienceThis study evaluates the impact of an adaptive feedback system in Pyrates, a programming serious game designed to ease the transition from block-based to text-based programming in high school classes. The adaptive feedback system was implemented to support student learning and lessen teachers' intervention workload in the classroom. To assess its effectiveness, a field user study was conducted with 190 high school students across two institutions. Results show that students progressed significantly further in the game when using the adaptive feedback system, as compared to playing without feedback, although it did not affect learning gains. We discuss the implications of these results for the design of adaptive feedback in programming serious games. CCS Concepts• Applied computing → Interactive learning environments; • Computing methodologies → Supervised learning by classification; • Human-centered computing → Field studies.</div
La peur dans l'activité des enseignants
No full textNational audienceCet article examine la peur du côté des enseignants. Alors que la souffrance au travail s’accroît (Lantheaume & Hélou, 2008), la peur d’enseigner devient un enjeu majeur, notamment pour les enseignants inexpérimentés confrontés à des élèves défiant les normes scolaires. Certains chercheurs qualifient ainsi l’enseignement de « métier à risque » (Blanchard-Laville, 2013). Cette peur s’intensifie dans un contexte de manque de reconnaissance et de soutien institutionnel. A ce titre, Boimare (2019) souligne que des pratiques pédagogiques rigides, associées à un déficit de formation, enferment les enseignants dans une routine aggravant les inégalités et le découragement. Par ailleurs, Obin (2024) met en évidence la montée de l’autocensure liée aux tensions idéologiques et religieuses, exacerbées par des événements comme l’assassinat de Samuel Paty. Ces analyses convergent pour appeler à une refondation visant à restaurer la liberté pédagogique, renforcer la cohésion républicaine et mieux protéger les enseignants
Left ventricular diastolic dysfunction is prevalent but not associated with mortality in patients with septic shock
No full textInternational audiencePurpose: Prognostic impact of left ventricular diastolic dysfunction (LVDD) in septic shock patients has not been determined using current diagnostic guidelines. We assessed the relation between LVDD during the first 3 days following intensive care unit (ICU) admission for septic shock and Day-28 mortality.Methods: This prospective, multicenter, observational study enrolled 402 patients (age: 63 ± 13 year; 59% male; SAPS II: 59 ± 20; SOFA: 9.4 ± 3.6; mechanical ventilation: 74%) with septic shock (Sepsis-3 definition). Patients were echocardiographically assessed within 12 h after admission (Day 1), on Day 2, Day 3, at ICU and at hospital discharge (or Day 28 whichever occurred first), using 2016 American-European guidelines.Results: LVDD was present at least once between Day 1 and 3 in 304 patients (76%), and in 56% and 44% of patients at ICU discharge and on Day 28 (or hospital discharge), respectively (43% of patients with follow-up). Seventy-eight of 172 patients (45%) exhibited similar LV diastolic properties throughout the study period while 58 patients (34%) improved their LVDD at follow-up (lower grade: n = 9, regression: n = 49). Day-28 mortality was not statistically different between patients with and without LVDD (80/304 [26%] vs. 25/88 [28%]; OR: 0.900 [0.530-1.527]; p = 0.696). Similar results were obtained when adjusting the multivariate model on SAPSII or SOFA score on admission, together with fluid balance during the first three days of ICU stay (OR: 0.838 [0.471-1.491]: p = 0.547 and OR: 0.887 [0.513-1.534]: p = 0.668, respectively).Conclusion: LVDD was highly prevalent in patients with septic shock but not associated with mortality. It appeared improving in one-third of survivors
Localised proper orthogonal decomposition
No full textInternational audienceProper Orthogonal Decomposition (POD) extracts an optimal orthonormal basis for reconstructing a sequence of data. This technique is widely used in fluid mechanics to construct reduced-order models for physical analysis, modelling, estimation, and control. However, when the number of snapshots is small and the spatial domain is large, convergence of the basis with respect to the number of samples is compromised. This often results in a degradation of the quality of the resulting reduced-order models. In this study, we propose a localisation procedure to mitigate convergence artefacts in the context of limited data. Specifically, we adapt Schur product-based localisation -commonly used in operational data assimilation -to the POD framework.We develop an algorithm that operates directly on the snapshots rather than on the large-scale correlation tensor. In addition, we introduce a family of partition-of-unity localisation functions to preserve the reconstruction properties of the localised POD basis. By artificially increasing the rank of the correlation tensor, we demonstrate that the localised POD, computed from a limited number of snapshots, can approximate the POD basis obtained from a larger dataset. This is illustrated using a wave field scattered by a turbulent jet in a rotating shallow water system. We further show that using smooth, overlapping localisation functions enables physically meaningful reconstructions. The reconstruction capabilities of the method are also demonstrated using a realistic internal wave field in the Gulf Stream region, based on a high-resolution numerical simulation.</p
Classification of complex power quality disturbances under noisy environment using Root-Music and least square techniques
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Harnessing the Pyclen Macrocycle for Advanced Two-Photon Bioimaging
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Association between treatment center volume and survival of endometrial cancer patients: A multicenter study: A Francogyn group study
No full textInternational audienceIntroduction: Endometrial cancer (EC) is the fourth most common cancer in women worldwide. The quality of care for EC patients may vary depending on the treatment center volume. The present study aimed to investigate the impact of center volume on the survival of EC patients.Methods: This multicenter retrospective study analyzed a large cohort of EC patients with type 1 and type 2 tumors treated between 2001 and 2020 in France. The study analyzed the impact of center volume on overall survival, as well as the impact of other factors such as age, FIGO stage, lymph node involvement, laparoscopic surgery, and overall recurrence.Results: The study found that treatment center volume had a significant impact on the overall survival of type 1 EC patients but not on type 2 EC patients. Other factors such as age, FIGO stage, lymph node involvement, laparoscopic surgery, and overall recurrence also impacted survival.Conclusion: Our study provides important insights into the quality of care for EC patients in France. The study's results highlight the impact of treatment center volume and other factors on survival and underscore the importance of high-quality care for all EC patients
Mine d’étain et atelier métallurgique d’As Muradellas (Baltar, Espagne). Campagne de fouille 2023: Campagne de fouille 2023
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From single to multi-stage forming process of copper thin sheet
No full textInternational audienceIn the electronics industry sector, different types of parts made out of copper alloys are used, such as metal supports (lead frames), on which the chips are assembled. These parts are produced using progressive dies, with several blanking and bending stages. There is a huge interest to numerically predict these multistage forming processes, to decrease design time and to anticipate production problems such as non-compliance with dimensional tolerances depending on the material used. This paper deals with the progressive forming of copper parts with single and multi-stage process coupled with experimental and numerical approaches for bending operations. The main contribution of this study is the design of a single stage bending tool for rectangular samples representative of multi-stage industrial processes, providing a relevant experimental database for numerical model validation. This device is based on the technology of progressive dies, though it allows the production of one part at a time. Instrumentation provides local load and displacement and an experimental database is built for Cu-ETP R290 copper strip. A multi-stage bending industrial process dedicated to the manufacturing of electrical contacts is also considered in this study. Numerical models of both single and multi-stage processes are developed, with a focus on the technological importance of a cam slider for the industrial process. The results show that the bending force is mainly influenced by the sample width. In addition, numerical models for the rectangular geometries capture some of the trends from the experiment such as the proportionality of the maximum force with the bent width. Overall, the models are able to predict springback within the process tolerance. Finally, comparison of one stage of the bending sequence with the single stage bending model showed that the single model approach gives similar results in terms of load and plastic deformation.</div