HAL-Université de Bretagne Occidentale
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Modélisation multi-échelle du comportement dissipatif de composites tissés 3D
No full textInternational audienceModélisation multi-échelle du comportement dissipatif de composites tissés 3
Évaluation combinée de la ténacité et de la performance de réparation dans les stratifiés unidirectionnels CF/PPS sous chargement statique et cyclique.
No full textInternational audienceÉvaluation combinée de la ténacité et de la performance de réparation dans les stratifiés unidirectionnels CF/PPS sous chargement statique et cyclique
Les workations : une innovation territoriale pour les territoires (périphériques) touristiques
No full textInternational audienceIn a context of changing professional and tourism practices, peripheral tourist regions are seeking to diversify their economies and reduce the seasonality of their activities. In this perspective, the concept of “workation,” or tracances, combining remote work and tourism, is emerging as a form of territorial innovation likely to transform the regions concerned. This paper examines how actors, particularly public ones, are appropriating this phenomenon in order to integrate it into their development strategies. The approach is based on a qualitative study including thirty interviews with coliving space managers in three peripheral regions (Algarve, Canary Islands, Azores), complemented by an analysis of grey literature and institutional websites. Preliminary results show that workations can indeed foster economic diversification, extend periods of activity, stimulate new forms of governance, and generate hybrid communities. More than a simple trend, they appear as a strategic opportunity to rethink certain territorial development models.Dans un contexte de mutation des pratiques professionnelles et touristiques, les périphéries touristiques cherchent à diversifier leur économie et à atténuer la saisonnalité de leur activité. Dans cette perspective, le concept de « workation », ou « tracances », combinant télétravail et séjour touristique, s’impose comme une innovation territoriale émergente, susceptible de transformer les espaces concernés. Cette communication interroge la manière dont les acteurs, notamment publics, s’approprient ce phénomène afin de l’intégrer dans leurs stratégies de développement. L’approche repose sur une enquête qualitative comprenant trente entretiens auprès de gestionnaires d’espaces de coliving dans trois régions périphériques (Algarve, Canaries, Açores), complétée par l’analyse de la littérature grise et des sites institutionnels. Les résultats préliminaires montrent que les workations peuvent bien favoriser la diversification économique, prolonger les périodes de fréquentation, stimuler de nouvelles formes de gouvernance et générer des communautés hybrides. Plus qu’une simple tendance, elles apparaissent comme une opportunité stratégique pour repenser certains modèles territoriaux de développement
FRAGMENTED OR UNIFIED? EXAMINING THE PARADIGM OF VULNERABILITIES IN SEXUAL HEALTH
No full textInternational audienceAbstract Objectives This study examines the scientific literature on vulnerabilities in the field of sexuality to investigate the existence of a coherent paradigm. Is there an identifiable scientific interest in this topic? What are the central questions asked? How have these questions evolved over time? Finally, can this paradigm be considered sexological, meaning centered around sexual health, sexual rights, and pleasure? Methods PubMed and Web of Science databases were queried using (vulnerability OR vulnerable) AND (sexuality OR sexual health), resulting in the collection and analysis of 21 343 articles published between 1968 and 2023. We examined the temporal evolution of the number of publications, the number of authors involved, and the interrelations between these authors to reveal research communities. The main keywords in these publications were analyzed to observe temporal evolution and their interconnections, using text-mining methods. Results Findings reveal a growing interest in vulnerabilities in sexual health since 2006, likely linked to the holistic definition of sexual health proposed by the WHO. Although numerous authors (77460) have contributed to this field, 86% have published only one article, indicating intermittent contributions. Only 2% of authors, considered experts with five or more publications, are distributed across 314 distinct communities, indicating field fragmentation and a lack of integration between research groups. The diversity of keywords (eg, infectious diseases, reproductive health, psychosocial dimensions) highlights a polymorphic field. Temporal analysis reveals three distinct periods between 2006 and 2023, demonstrating a paradigmatic shift: an initial focus on epidemiological and biomedical issues (2006–2013), followed by a transition towards a more holistic, social, and interactional approach (2019–2022). However, concepts related to pleasure and sexual rights remain marginal within the network of conceptual interrelations, limiting the unification of the field under a fully sexological paradigm. Conclusions The paradigm of vulnerabilities in sexual health remains fragmented, primarily oriented towards social and biomedical needs, and lacks proactive integration of sexological perspectives centered on sexual rights and pleasure. This fragmentation hinders the theorization of sexology as an autonomous field and reduces the specificity of the discipline within sexual health. Conflicts of Interest None
Static and vibration of two-phase peridynamic rods or strings under general boundary conditions – Exact, FDM and FEM approaches
No full textInternational audienceStatic and dynamic analysis of two-phase peridynamic one-dimensional systems is thoroughly investigated in this paper for various boundary conditions by exact and numerical approaches. Such nonlocal study concerns the axial or torsional responses of two-phase peridynamic rods or the behaviour of a two-phase peridynamic string. For a normalized exponential kernel, the integro-differential equation of the two-phase peridynamic problem can be converted as a linear higher-order differential equation with constant coefficients. Exact static solutions of fixed-fixed and fixed-free two-phase peridynamic axial rod under uniform distributed loading and concentrated force are analytically derived. It is shown that the pure peridynamic rod problem can be ill-posed due to a conflict between the natural boundary condition and the peridynamic constitutive boundary condition. The two-phase peridynamic problem may be justified from physical arguments, and is also seen as a regularized peridynamic problem. The exact eigen-frequencies of the two-phase peridynamic rods are also analytically obtained for various boundary conditions, including fixed-free, fixed-fixed or free-free boundary conditions. These theoretical approaches are corroborated by numerical investigations based on FDM (Finite Difference Method), FEM (Finite Element Method), exact FEM and variational iterative methods. Two FDM schemes are presented for the statics and the vibration of two-phase peridynamic rods, with convergence orders of 1 and 2, respectively. Moreover, three different FE procedures are proposed as: (1) FEM for direct solving the integro-differential equations of two-phase peridynamic one-dimensional system, (2) FEM for discretizing the pure differential equations, and (3) Exact FEM to obtain both the exact stiffness matrix and exact dynamic stiffness matrix of two-phase peridynamic onedimensional system, based on Eisenberger's methodology. The order of convergence for the first and the second proposed FEM are equal to 2 and 4, according to the type of selected finite elements. Moreover, the third proposed FEM based on the exact shape function of the peridynamic problem gives the exact solution from one single FEM element. In addition, the variational iterative method of Stodola-Vianello is successfully applied to the two-phase peridynamic eigenvalue problems
Management of life-threatening bleeding: Application of Learned Experiences from the Critical Care Clinical Trialists (3CT) Workshop
No full textInternational audienceResume: Mortality from major bleeding in trauma patients is highest within the first six hours post-injury. Advances in patient management, driven by national guidelines and clinical trials, have significantly improved outcomes. However, variability in patient profiles, clinical presentations, and standard care practices complicates the assessment of treatment efficacy in clinical trials. In June 2024, international experts convened at the Critical Care Clinical Trialists (3CT) Workshop to examine the evolution of massive bleeding management and the impact of patient and treatment heterogeneity on trial design. This opinion article builds on the workshop discussions and underscores key considerations for the interpretation of large-scale studies. Three main conclusions emerged: First, the need for standardized definitions of “massive bleeding,” “life-threatening bleeding,” and “massive transfusion” to ensure consistent patient classification and treatment strategies. Second, the importance of tailored approaches that account for patient heterogeneity, including the careful selection of target populations and the use of appropriate primary endpoints. Third, the necessity of methodological adaptations in emergency research settings, such as implementing deferred consent procedures, conducting interim analyses, and using automated adjudication systems to improve objectivity and trial efficiency. In summary, harmonizing terminology, embracing clinical diversity, and refining trial design are essential to enhance the quality, comparability, and clinical relevance of research in massive bleeding. These measures ultimately aim to improve outcomes for critically bleeding patients
Analysis of turbulent flow and thermal performance of plate-pin fins heat sink fitted with a shield in the bypass
No full textInternational audienceIn this article, a numerical analysis study has been performed to investigate the dynamic and thermal performances of a plate pin fin heat sink. Four types of pin fin shape are used, such as square (oriented 45° relative to the air flow), cylindrical, elliptical, and drop-form, and a transverse fin (shield) with adjustable height (Hs = 6, 10 and 13 mm) arranged in the bypass. The range of Reynolds number is studied between Re = 2 × 103 and Re = 12 × 103. The finite volume method was used to solve the governing equations. The thermal and dynamic results are presented in terms of Nusselt number and friction factor respectively; and as a function of Reynolds number. All the cases were compared with a plate fin heat sink. It is found that an enhancement of performance showed by implanting the pin-fin between the plate fin and fitting a shield in the bypass
A recurrence formula in reciprocal frame structures: the Da Vinci bridge
No full textInternational audienceThis article studies a reciprocal system referred to as the “Da Vinci bridge” and first proposed by Leonardo Da Vinci in the Codex Atlanticus written in 1495. The concept of reciprocal systems consists in transferring forces using planar or elongated elements in such a way to form a closed circuit. Reciprocal systems are usually built from the repetition of a building block. In the case of the Da Vinci bridge, the building block is an assembly of four beams. This article uncovers a recurrence formula linking the number of building blocks to the reaction forces on the most loaded beams of the bridge. It is interesting to note that the recurrence formula differs if the system consists in an even or odd number of building blocks. The various hypotheses of the strength of material computations that led to the recurrence formula are validated by comparison with an experimental realization. This studies shows that, when designing reciprocal systems, an optimization has to be carried out in order to chose between using long beams or using a large number of building elements.Cet article étudie un système réciproque appelé « pont de Léonard De Vinci », proposé pour la première fois par Léonard de Vinci dans le Codex Atlanticus rédigé en 1495. Le concept des systèmes réciproques consiste à transférer les forces à l'aide d'éléments plans ou allongés de manière à former un circuit fermé. Les systèmes réciproques sont généralement construits à partir de la répétition d'un élément de construction. Dans le cas du pont de Léonard De Vinci, l'élément de construction est un assemblage de quatre poutres. Cet article démontre une formule de récurrence reliant le nombre d'éléments de construction aux forces de réaction sur les poutres les plus sollicitées du pont. Il est intéressant de noter que la formule de récurrence diffère si le système est constitué d'un nombre pair ou impair d'éléments de construction. Les différentes hypothèses de calculs de résistance des matériaux ayant conduit à la formule de récurrence sont validées par comparaison avec une réalisation expérimentale. Cette étude montre que, lors de la conception de systhèmes réciproques, une optimisation doit être effectuée afin de choisir entre l'utilisation de poutres longues ou l'utilisation d'un grand nombre d'éléments de construction
Derivation and Numerical Assessment of a Stochastic Large–Scale Hydrostatic Primitive Equations Model
No full textInternational audienceAbstract Planetary flows are shaped by interactions at scales much smaller than the flows themselves, with mesoscale and sub–mesoscale eddies playing key roles in mixing, particle transport and tracer dispersion. To capture these effects, we introduce a stochastic formulation of the primitive equations within the Location Uncertainty (LU) framework. Derived from conservation principles via a stochastic Reynolds transport theorem, this approach decomposes velocity into a smooth–in–time large–scale component and a random–in–time field representing unresolved scales effects. To model the velocity noise term, we develop two data–driven methods based on Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) and extend this to hybrid approaches combining model– and data–driven constraints. Simulations show that the LU framework enhances gyre flow predictions, improving mixing, jet structure, and tracer transport while revealing the interplay between small– and large–scale dynamics
The bright and dark sides of openness on quality of life: the role of emotions and self-efficacy beliefs within a GAMs, a network approach and mediation
No full textInternational audienceBackground: Although the relationship between personality and quality of life has been extensively studied, openness has received relatively little attention. This is despite its importance in the Big Five model and its ability to change over time. To close this gap, our study explored the link between openness and quality of life. Additionally, we examined whether this relationship is influenced by Dimensions of Openness to Emotion (DOE) and self-efficacy, as research suggests both may play significant roles in the personality-quality of life relationship.Method : A total of 419 participants in a community-based convenience sample of the French-speaking regions of Switzerland and of France aged 20-66 years completed the NEO-FFI-R inventory, the General Self-Efficacy Scale, the Dimensions of Openness to Emotion scale, and the WHOQOL-12 measuring quality of life. GAMs, Network and Mediation analysis were conducted with R software. Results: Our analysis suggested that the different facets of DOE relate to quality of life in two contrasting ways, with openness influencing it both positively and negatively, depending on the specific facet: the somatic dimensions of DOE had a negative association, while the cognitive dimensions of DOE had a positive one. Conclusions: Openness contributes to quality of life, especially for individuals who are moderately open to their bodily sensations and who use thoughtful and context-adjusted emotion regulation strategies