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Instruments de financement de la recherche publique et transformation des savoirs juridiques
No full textInternational audienc
Multi-Objective Monarch Butterfly Optimization algorithm for agri-food workflow scheduling in fog–cloud
No full textInternational audienceThe explosion of data and connected objects has encouraged the development of distributed computing environments such as cloud, fog and edge, facilitating real-time data processing. In the agri-food sector, this evolution is reinforced by the emergence of the Industrial Internet of Things (IIoT) and fog–cloud computing. One of the major challenges of these environments is the efficient scheduling of applications while respecting the SLA principle. This article deals with the multi-objective optimization of agri-food workflow scheduling using an improved version of the Monarch Butterfly Optimization (MO-MBO) algorithm. Our approach integrates Pareto dominance, a greedy strategy, and a self-adaptive strategy to effectively handle four conflicting objectives: makespan, cost, energy, and latency. Simulations carried out on FogWorkflowSim for the agri-food health monitoring workflow demonstrate that MO-MBO is energy-efficient (68.63% compared to the genetic algorithm (GA), 67.78% compared to the particle swarm optimization algorithm (PSO), and 85.48% compared to the Non Dominated Sorting Genetic Algorithm-II (NSGA-II)) and improves latency (0.35% for GA, 0.14% for PSO, and 0.10% for NSGA-II). However, cost increases marginally, by 0.85% for GA, 0.29% for PSO, and 0.10% for NSGA-II. Makespan, meanwhile, increases by 31.41% versus GA, 29.27% versus PSO, and 10.67% compared versus NSGA-II. The results highlight the ability of MO-MBO to effectively balance multiple, conflicting objectives, making it a promising solution for energy-efficient, low-latency scheduling in fog–cloud systems
Critical review of hybrid modular multilevel converters for HVDC transmission in offshore wind energy
No full textInternational audienceFor the integration of wind energy into the transmission system, High Voltage DC (HVDC) is the most efficient and cost-effective option. Modular multilevel converters have emerged as the most suitable converters for the required AC/DC conversions. To maintain power availability, stability, and reliability in the HVDC transmission, the converters' ability to offer fault ride-through (FRT) and work as static compensators (STATCOM) during DC faults have become important requirements. The conventional half bridge-based MMC is the most cost-effective, efficient, and widely used topology, but it cannot meet these requirements. Though full-bridge MMC has this ability, it doubles the converter cost, device count, and losses. In the present MMC topology, the capacitors occupy 50 % of the volume and 80 % weight of the converter. Reducing energy storage requirements is needed for their efficient use in offshore wind energy substations. Many Hybrid MMC (HMMC) topologies have been introduced in the last few years to offer a solution to meet these requirements, but no topology has been found yet that can fulfill all the required criteria. A comprehensive review of the existing topologies, their features, strengths, and drawbacks are needed to identify research gaps and guide future works. This paper provides a thorough and systematic review of the topology, fault handling, and STATCOM mode of all hybrid MMCs (HMMCs) for HVDC offshore wind energy transmission found in the literature. It compares these topologies' structure, losses, and functionality to guide future research. A case study calculates these topologies' losses and energy requirements by using time-domain analysis of a switching-based model in MATLAB of these converters, with a rating of 1500MVA with 1050KV DC voltage. The results present a quantitative comparison of losses and energy storage requirements across these topologies which would be useful to give directions to future works
Cacao stand rehabilitation practices affect long-term cocoa production in agroforestry systems in Cameroon
No full textInternational audiencePrevious studies suggest that the density and diversity of associated trees stabilises cocoa agroforestry systems (cAFS) production in the long term. However, the impact of cocoa rejuvenation practices on this stabilisation process remains unclear. This study investigated how farmers' practices, particularly cocoa stand management, influence long-term cocoa yields, considering the production area's history and current management. Cocoa plantations aged from 7 to over 60 years were selected in two areas: an old cocoa production area (Bakoa) and a cocoa pioneer front in the forested land (Talba) in Cameroon's Centre region. Measurements included cocoa and associated tree diameters, shade tree cover and accessible cocoa yield. We also identified architectural types of cocoa trees representing various development stages. Results showed no effect of plantation age on associated tree parameters at either site. In Talba, cocoa tree density and accessible yield decreased with plantation age. This decline was associated with an increase in senescent cocoa trees and few regenerated multi-stem trees over time. This indicates poor rejuvenation of existing plantations in Talba, where forest reserves are available to create new ones. Conversely, in Bakoa, an area with no available forest reserves, rejuvenation of existing plantations, evidenced by the increasing density of multi-stem cocoa trees and new seedlings over time, was associated with stable yields in the long term. Providing farmers with training and incentives to rejuvenate old cocoa stands should be part of an overall strategy to increase production, improve farmers' incomes, protect forests</div
Proceedings of Digital Avenues for Low-Resource Languages of Sub-Saharan Africa (DASSA 2025)
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/614384/)International audienc
Unveiling synergistic antioxidant combinations for α-Tocopherol in emulsions: A spectrophotometric-mathematical approach
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/613931/)International audienceThis study presents a novel method based on a spectrophotometric assay coupled with mathematical modeling (Weibull interactions modeling CAT) to evaluate synergistic interactions of antioxidants in an oil-in-water model emulsion. The approach addresses a major limitation in current assays by eliminating interference from pro-/antioxidant pathways induced by exogenous radical initiators or buffers, allowing for a more accurate assessment of antioxidant efficacy. Using the Weibull equation, key kinetic parameters (LagP, α, β) were extracted to characterize the impact of antioxidant combinations on lipid oxidation. Results showed that certain combinations, such as α-tocopherol with carnosic acid, dieckol, and myricetin, exhibited concentration-dependent synergistic effects. Among these, carnosic acid in equimolar ratios demonstrated particularly promising interactions. In contrast, ascorbic acid revealed antagonistic behaviour when combined with α-tocopherol. Additionally, the presence of ferrous ions significantly influenced antioxidant interactions, highlighting their role in modulating underlying mechanisms. Overall, carnosic acid and dieckol emerged as strong candidates for use in combination with α-tocopherol under specific conditions. This method provides a refined approach for screening antioxidant synergies and contributes to the development of more effective antioxidant formulations in emulsified systems
Récit et mise en scène de soi: Regards pluriels
No full textInternational audienceCroisant les apports des sciences humaines, de la littérature et des arts visuels, ce volume, qui s’inscrit dans une perspective résolument interdisciplinaire, invite à découvrir tout l’éventail des possibles qu’ouvre le récit de soi. Réfléchir au récit de soi nous invite à penser à la manière dont se construit la subjectivité. En écrivant sa propre histoire « je devient un autre » : il devient personnage de sa propre histoire et infuse un sens à la succession des événements. Prendre la parole pour écrire sa propre histoire permet aussi d’accéder au statut de sujet et se trouve ainsi au cœur de diverses stratégies d’empowerment. Ce volume, qui s’inscrit dans une perspective résolument interdisciplinaire, analyse les différentes formes et fonctions que peut revêtir le récit de soi : récit autobiographique, journal intime, auto-analyse, notes éparses reflétant une identité fragmentée au fil du temps et des circonstances, exposition photographique, autofiction, essai… Ces différentes déclinaisons de l’écriture de soi effectuent une mise en récit de l’histoire personnelle et ouvrent un vaste éventail de possibilités incluant toutes les nuances qui vont de l’histoire à la fiction. Croisant les apports des historiens, des spécialistes de littérature (française, antique et étrangère), des ethnologues et des spécialistes des arts visuels, ce volume articule réflexion méthodologique et analyse de cas. Depuis auteurs de la Rome antique jusqu’à la BD et la photographie contemporaines, les auteurs montrent la richesse des perspectives qu’ouvre un récit de soi en perpétuelle réinvention : se représenter, raconter sa vie ou un fragment de celle-ci demeure un des enjeux les plus actuels
Accès à l'électricité et développement humain au Mali : une évaluation empirique fondée sur le modèle ARDL
No full textInternational audienceAbstract : This study examines the impact of access to electricity, access to clean water, public health expenditures, and the school enrollment rate on the Human Development Index (HDI) in Mali over the period 2000–2023. The dataset consists of reliable national time series with 24 annual observations, allowing for a coherent assessment of both short- and long-term dynamics. The analysis is based on an ARDL (Autoregressive Distributed Lag) model, suitable for mixed-order integrated series, which distinguishes between immediate and lasting effects of the explanatory variables. The estimated results indicate that, in the long run, access to electricity has a positive and statistically significant effect on HDI, confirming its central role as a structural infrastructure. In contrast, the coefficients for access to clean water and public health expenditures are negative and significant, which may reflect inefficiencies or governance issues in the management of these public services rather than an inherently adverse effect. School enrollment, on the other hand, does not show a significant effect according to the estimated model. These findings underscore the importance of strengthening electrical infrastructure while improving the quality and management of public services to support sustainable human development in Mali. The study has certain limitations, notably the small size of the annual sample and the absence of detailed regional data, which limits the generalization of the results. These constraints provide avenues for future research incorporating regional or sectoral data to better understand the determinants of human development. Keywords : Human development, access to electricity, clean water, health expenditures, school enrollment, ARDL, Mali. JEL Classification : C32, O15, Q41, O55 Paper type : Empirical researchRésumé : Cette étude analyse l’impact de l’accès à l’électricité, à l’eau potable, des dépenses publiques en santé et du taux de scolarisation sur l’indice de développement humain (IDH) au Mali, sur la période 2000-2023. La base de données mobilisée comprend des séries temporelles nationales fiables, couvrant 24 observations annuelles, permettant une évaluation cohérente des dynamiques à court et à long terme. L’analyse repose sur un modèle ARDL (Autoregressive Distributed Lag), adapté aux séries intégrées d’ordres mixtes, qui permet de distinguer les effets immédiats et durables des variables explicatives. Les résultats estimés à partir du modèle ARDL indiquent qu’à long terme, l’accès à l’électricité exerce un effet positif et statistiquement significatif sur l’IDH, confirmant son rôle central comme infrastructure structurante. À l’inverse, les coefficients estimés pour l’accès à l’eau potable et pour les dépenses publiques en santé sont négatifs et significatifs, ce qui peut refléter des inefficiences ou des problèmes de gouvernance dans la gestion de ces services publics, plutôt qu’un impact intrinsèquement défavorable. Le taux de scolarisation, quant à lui, n’a pas d’effet significatif selon le modèle estimé. Ces constats soulignent l’importance de renforcer les infrastructures électriques tout en améliorant la qualité et la gestion des services publics pour soutenir un développement humain durable au Mali. L’étude comporte toutefois certaines limites, notamment la taille réduite de l’échantillon annuel et l’absence de données régionales détaillées, ce qui restreint la généralisation des résultats à l’ensemble du pays. Ces contraintes ouvrent des perspectives pour des recherches futures intégrant des données régionales ou sectorielles afin d’affiner la compréhension des déterminants du développement humain. Mots clés : Développement humain, accès à l’électricité, eau potable, dépenses de santé, scolarisation, ARDL, Mali. Classification JEL : C32, O15, Q41, O55 Type du papier : Recherche empiriqu
Improving service performance in young tennis players: the superiority of dynamic over static motor imagery
No full textInternational audienceThis study investigated the effect of dynamic motor imagery (MI), combined with physical practice, on service performances. 12 young non-expert tennis players (Mage = 11.08 years), between 3 and 5 years of regular practice, volunteered to participate in this study. They completed 3 experimental counterbalanced sessions: Control (including a neutral task), Static MI (with external visual imagery) and Dynamic MI (with external visual imagery including slight movements miming the actual service), which included the completion of 10 services in match condition with a returner present. Percentage of success, serve speed, technical and efficiency scores (assessing the degree of difficulty in which the receivers found themselves following services) were used as dependent variables and performance indicators. The results revealed that compared to the Control session, both MI conditions (Static and Dynamic motor imageries) improved the percentage of successful serves as well as technical and efficiency scores, but the improvement was greater when using Dynamic MI compared to Static MI. We recommend the use of integrated dynamic motor imagery before actual execution, such as serving, to improve motor learning and performance
GENDER DIFFERENCES IN THE ASSESSMENT OF CARDIOVASCULAR RISK, AND CONTROL OF BLOOD PRESSURE AND LDL-CHOLESTEROL: A SUBANALYSIS OF THE SNAPSHOT STUDY IN EUROPE
No full textInternational audienceObjective:This pre-specified subgroup analysis aims to assess differences in cardiovascular (CV) risk, blood pressure (BP) and LDL-C control between genders in hypertensive patients.Design and method:SNAPSHOT is a cross-sectional, epidemiological, multicentre study conducted in 9443 patients with hypertension from six European countries (Bulgaria, Croatia, Georgia, Romania, Serbia, and Spain). Investigators estimated BP and LDL-C control, and CV risk according to their clinical practice. Estimated CV risk categories were compared to the calculated CV risk based on SCORE2&2-OP.Results:5281 women and 3996 men were analyzed. Women tended to be older than men (66.9±10.0 years vs. 64.3±11.0 years), while men were more likely to be smokers (21.5% vs. 13.9%) and overweight/obese (BMI 29.6±7.3 kg/m2 vs. 29.2±6.5 kg/m2), p<0.001 for all. Two or more risk factors (age>65years, BMI>30 kg/m2, smoking) were reported in 30.4% of women and in 29.3% of men (in addition to the male gender risk factor). Presence of dyslipidemia and type 2 diabetes were higher in men than women (82.7% vs. 81.1%, p<0.05 and 36.4% vs. 30.8%, p<0.001).Mean SBD/DBP were higher in men than women (139.9±17.0/83.3±11.2 mmHg vs. 138.8±17.4/81.5±10.4 mmHg, p<0.001). According to guidelines, BP was controlled in more women than men (26.7% vs. 21.6%, p<0.001). Mean LDL-C was higher in women than men (123.8±45.9 mg/dL vs. 114.3±46.0 mg/dL, p<0.001). According to guidelines, LDL-C was controlled in less women than men (6.0% vs. 9.9%, p<0.001).Estimated CV risk categories, compared to calculated CV risk, were: very high (18.1% women, 30.1% men vs. 84.7%, 88.4%); high (31.3%, 33.8% vs. 13.5%, 11.1%); and low-to-moderate (50.6%, 36.0% vs. 1.8%, 0.5%).Compared to guidelines, CV risk was more frequently underestimated by investigators in women (76.5%) than in men (65.7%), whereas it was accurately categorized less frequently in women (22.1%) than in men (32.7%) (both p<0.001, Figure).figure1Conclusions:This subanalysis showed that investigators underestimated CV risk more often in women than in men. Women had lower LDL-C control, but better BP control compared to men. When developing and implementing interventions to improve BP control in the European population, we believe gender differences must be considered to improve effectiveness