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Asymptotically period doubling bifurcation of fractional difference equations
No full textInternational audienceNonlinear dynamics of fractional difference equations have recently received much attention. This paper investigates asymptotically period doubling bifurcation. By theories of discrete fractional calculus, the existence conditions for asymptotically period-2 and −4 cycles of fractional difference equations are given. New numerical schemes are employed to determine critical values. Finally, the fractional Hénon map is used as a high-dimensional example. It can be concluded that this paper provides a way of understanding the route to chaos in fractional difference equations
A Heterogeneous SoC Design with RISC-V Processor and SNN Accelerator
No full textThis internship primarily focused on integrating an existing neural network accelerator into an open-source system. The main challenge was ensuring correct interface alignment between the accelerator and the system, with particular emphasis on adapting timing logic and enabling parallelization. Starting from the original interface design, we identified key issues that prevented seamless integration and proposed modifications to resolve them. The work involved detailed redesign of the communication modules, followed by verification of functional correctness using a reference framework. Finally, we conducted preliminary power consumption analyses across different datasets to evaluate the system’s efficiency. Overall, this report presents both the technical challenges encountered during integration and the practical solutions developed, offering insights into efficient accelerator–SoC co-design.Ce stage s'est principalement concentré sur l'intégration d'un accélérateur de réseaux de neurones existant dans un système open-source. Le principal défi consistait à assurer une correspondance correcte entre les interfaces de l'accélérateur et celles du système, en mettant particulièrement l'accent sur l'adaptation de la logique temporelle et la mise en place d'une parallélisation. A partir de la conception initiale de l'interface, nous avons identifié les problèmes clés empêchant une intégration fluide et proposé des modifications permettant de les résoudre. Ce travail a nécessité une refonte détaillée des modules de communication, suivie d'une vérification de la justesse fonctionnelle à l'aide d'un cadre de référence. Enfin, nous avons mené une analyse préliminaire de la consommation énergétique sur différents jeux de données afin d'évaluer l'efficacité du système. Dans l'ensemble, ce rapport présente les défis techniques rencontrés lors de l'intégration ainsi que les solutions pratiques développées, et propose des pistes pour une co-conception plus efficace entre accélérateurs et SoC
The SORTEE Guidelines for Data and Code Quality Control in Ecology and Evolutionary Biology
No full textOpen data and code are crucial to increasing transparency and reproducibility, and in building trust in scientific research. However, despite an increasing number of journals in ecology and evolutionary biology mandating for data and code to be archived alongside published articles, the amount and quality of archived data and code, and subsequent reproducibility of results, has remained worryingly low. As a result, a handful of journals have recruited dedicated data editors, whose role is to help authors increase the overall quality of archived data and code. There is, however, a general lack of consensus of what a data editor should check, how to do it, and to what level of detail, and the process is often vague and hidden from readers and authors alike. Here, with the input from multiple data editors across several journals in ecology and evolutionary biology, we establish and describe the first standardised guidelines for Data and Code Quality Control on behalf of the Society for Open, Reliable, and Transparent Ecology and Evolutionary Biology (SORTEE). We start by introducing the concept of a data editor and data and code quality control, what is expected from data and code quality control, the relative costs and benefits to journals, authors, and readers, and then introduce and detail the SORTEE-led guidelines, ending with advice for journals and authors. We believe that by adopting these standardised guidelines, journals will help increase the consistency and transparency of the data editor process for readers, authors, and data editors
Evaluating the resilience of steppe grassland ecosystems of the Southern Caucasus under differing social mediated land-use patterns
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Assessing 3D and 2D hydrodynamic models for urban flood simulations: a district scale analysis with experimental street-level discharge, height and velocity
No full textInternational audienceUrban flood modeling is essential for understanding physical phenomena and enhancing flood forecasting. The relevance of these numerical tools must be assessed with flow measurements which are sparse for real floods. This article assesses the capability of state-of-the-art 2D (with or without k-ϵ turbulence model) and 3D (with k -ω SST turbulence model) numerical models in reproducing the characteristics of urban flood flows within a real-like street network using an experimental dataset. The results show that all models can predict the flow discharge distribution and flow depths inside the district. The 3D model is always slightly more accurate, especially in zones where the flow is strongly perturbed. The comparison of numerical and experimental velocity profiles across streets highlights the need of a turbulence model to represent recirculation areas of finite length after crossroads and obtain a more realistic velocity field and water elevation profile
Pushing Vertices to Make Graphs Irregular
No full textInternational audienceIn connection with the so-called 1-2-3 Conjecture, we introduce and study a new problem related to proper labellings. In the regular problem, proper labellings of graphs are designed by assigning strictly positive labels to the edges so that any two adjacent vertices get incident to distinct sums of labels, and the main goal, for a given graph, is to minimise the value of the largest label assigned. In the new problem we introduce, we construct proper labellings through pushing vertices, where pushing a vertex means increasing by the labels assigned to all edges incident to that vertex. We focus on the study of two related metrics of interest, being the total number of times vertices have been pushed, and the maximum number of times a vertex has been pushed, which we aim at minimising, for given graphs. As a contribution, we establish bounds, some of which are tight, on these two parameters, in general and for particular graph classes. We also prove that minimising any of the two parameters is an \textsf{NP}-hard problem. Finally, we also compare our new problem with the original one, and raise directions and questions for further work on the topic
Multichannel Chromatic Dispersion Measurement Using Long-Period Fibre Gratings: tests of Wine Fermentation Monitoring
No full textInternational audienceOptical fibre sensors (OFS) offer potentials to the challenging continuous control of manufacture processes, because they are reliable, cheap, versatile and, quite critically, fast. For example in the food and drink industry, monitoring is usually performed randomly and off-line. In contrary, OFS are sturdy, are easy to implement on-line for continuous monitoring, have a small footprint and typical response times of less than minutes or even seconds, depending on the required sensitivity and limit of detection. In particular, measuring of the chromaticdispersion (CD) of liquids may provide very interesting insight in the progress of the manufacture. For instance, in the wine industry, fermentation of must extracted from grapes is complex and dynamical. Its monitoring is done on experimental model production lines, using performant techniques such as HPLC. OFS have proven interesting performances, mostly for temperature, and refractive index. Recently, we have proven the concept of an original multi-channels CD sensor using a dual long-period fibre grating (Bi-LPG). Wedemonstrated that some chemical compounds in liquids could be discriminated from others through their CD signature. Indeed, each LPG attenuation band being associated with the matching of the core mode to one cladding mode (that interacts with the external medium via its evanescent field), all « channels » are independent refractive index sensors, and can be used to estimate the CD of the surrounding medium
La personne âgée face à l’édentement complet : accompagnement vers une réhabilitation prothétique amovible
No full textThe transition to total tooth loss is a particularly challenging stage, both functionally and psychologically. It constitutes a major alteration of the oral cavity, disrupting vital functions such as mastication, deglutition, phonation, and facial expression, and significantly affecting patients’ psychosocial well-being. In this context, while complete removable dentures are often indicated in clinical practice, they present inherent limitations regarding stability, comfort, and functional performance.The loss of natural occlusion and proprioceptive feedback leads to diminished masticatory efficiency, prompting unfavorable dietary adaptations that frequently result in undernutrition. Yet, for elderly individuals, eating remains one of the few enduring pleasures of life; it must therefore remain a convivial, satisfying, and tailored experience. Supporting patients through the transition to complete edentulism and ensuring the success of their prosthetic rehabilitation are crucial factors in preventing or mitigating the deterioration of general health status.In this regard, the role of the dental surgeon extends beyond technical intervention. The quality of the practitioner–patient relationship plays a central role, influencing treatment adherence, prosthetic adaptation, and the prevention of complications. Attentive listening, clear communication, and individualized support help foster patient trust, better address expectations, and transform prosthetic rehabilitation into an opportunity for nutritional rebalancing and enhanced overall well-being.L’édentement complet chez la personne âgée représente une problématique fréquente et complexe tant pour le chirurgien-dentiste que pour le patient. Le passage à l’édentement total représente une étape particulièrement éprouvante, tant sur le plan fonctionnel que psychologique. Il s’agit en effet d’une altération majeure de la cavité buccale, perturbant des fonctions vitales telles que la mastication, la déglutition, la phonation ou encore l’expression du sourire, et impactant le bien-être psycho-social des patients. Dans ce contexte, la prothèse amovible complète, bien qu’indiquée dans de nombreuses situations cliniques, présente des limites en termes de stabilité, de confort ou de restitution fonctionnelle.La perte de l’occlusion naturelle et des repères proprioceptifs entraîne une diminution des performances masticatoires, conduisant à des ajustements alimentaires défavorables, souvent sources de dénutrition. Or, pour les personnes âgées, l’alimentation demeure l’un des derniers plaisirs de la vie ; elle doit donc rester conviviale, adaptée, et source de satisfaction. Accompagner les patients dans leur transition vers l’édentement complet, et assurer la réussite de leur traitement prothétique, sont des facteurs clés pour prévenir ou corriger toute détérioration de leur état de santé général. Dans ce contexte, le rôle du chirurgien-dentiste dépasse le simple cadre technique et la qualité de la relation entre le praticien et le patient joue un rôle central. Elle conditionne l’adhésion au traitement, la réussite de l’adaptation prothétique et la prévention des complications. Une écoute attentive, une communication claire et un accompagnement individualisé permettent de renforcer la confiance du patient, de mieux répondre à ses attentes, et de faire de la réhabilitation prothétique une véritable opportunité du rééquilibrage alimentaire et du bien-être global
The tangent cone to the real determinantal variety: various expressions and a proof
No full textThe set of real matrices of upper-bounded rank is a real algebraic variety called the real generic determinantal variety. An explicit description of the tangent cone to that variety is given in Theorem 3.2 of Schneider and Uschmajew [SIAM J. Optim., 25 (2015), pp. 622-646]. The present paper shows that the proof therein is incomplete and provides a proof. It also reviews equivalent descriptions of the tangent cone to that variety. Moreover, it shows that the tangent cone and the algebraic tangent cone to that variety coincide, which is not true for all real algebraic varieties
