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Modélisation géographique floue des pratiques de pêche lagonaire à Moorea
No full textNational audienc
A Large-Scale Optimization Framework for Simultaneous Design and Routing of Wind-Assisted Ships
No full textInternational audienceThis paper presents a comprehensive approach to optimizing the performance of wind-assisted ships. The proposed optimization framework simultaneously addresses ship routing and design, considering the complex interactions between design parameters and route optimization across multiple weather scenarios. Optimal control methods, including the direct multiple shooting technique and automatic differentiation, are employed to efficiently optimize both routing and design parameters, resulting in a large-scale optimization problem. The methodology is demonstrated through a case study of a 2200-TEU container ship equipped with Flettner rotors, operating on a transatlantic route between Brittany and Halifax. The results provide an objective estimate of fuel savings, highlighting the importance of integrated optimization for wind-assisted propulsion systems, while maintaining computational efficiency suitable for iterative design processes. Compared to conventional methods, this approach drastically reduces optimization times, enabling rapid design iterations and informed decision-making. Furthermore, the study offers insights into the sensitivity of fuel consumption to key design parameters, such as the number and placement of Flettner rotors, providing a more accurate and comprehensive estimate of potential energy savings compared to conventional methods. By overcoming the limitations of traditional polar-diagram-based methods, this framework provides a more accurate and dynamic assessment of wind-assisted propulsion systems. These findings emphasize the necessity of integrated optimization for maximizing performance and sustainability in maritime transport
La place de la géomorphologie dans les parcs nationaux de l’Ouest américain : précocité et exemplarité
No full textLettre d'informatio
Shape optimization of a flexible flapping wing with hovering kinematics
No full textInternational audienceFlapping wings demonstrate exceptional aerodynamic performance and the optimization of wing shape is an important issue within this field. A numerical optimization targeting wing lift maximization is conducted on a two-dimensional flapping wing with chordwise flexibility. A commonly used setup is to consider two rigid elliptical-section components connected by a torsional spring, providing chordwise flexibility. The leading body of the wing operates under specified hovering flapping kinematics, while the trailing body responds passively. Starting from this setup, the airfoil shape is parameterized using three parameters and optimized for maximum lift using the Simplex algorithm. Four configurations of the wing are evaluated, and the results indicate lift increase across all configurations, with a maximum increase in 10.6%. The optimized airfoil configuration adopts a teardrop profile, substantially narrower than the original elliptical section. According to further analysis, the lift increase can be primarily attributed to the enhancement of velocity circulation
Commons e possesso: l'ambiguità giurisdizionale delle risorse idriche in Cerdagna (XIX-XX sec.)
No full textInternational audienc
Assessing linkages between supply chain tokens and other assets: Evidence from a time-frequency quantile connectedness approach
No full textInternational audienceThis study assesses return spillovers and hedging dynamics between supply chain tokens and traditional assets, including equities, currencies, bonds, gold, oil, and Bitcoin, using a time-frequency quantile connectedness approach. Findings reveal that while supply chain tokens exhibit weak connectedness with traditional assets during stable periods, heightened market volatility, such as during the COVID-19 pandemic, significantly increases return spillovers, particularly from equities and Bitcoin. Supply chain tokens offer some diversification potential, especially when paired with oil (WTI), but their effectiveness as hedging instruments varies by time horizon and market conditions. Optimal portfolio weights and hedge ratios suggest that investors should dynamically adjust allocations to mitigate risks effectively, particularly during market instability. These insights emphasize the need for adaptable portfolio strategies when integrating supply chain tokens with traditional assets
Aarskog-Scott syndrome: a clinical study based on a large series of 111 male patients with a pathogenic variant in FGD1 and management recommendations
No full textInternational audienceBackground: Aarskog-Scott syndrome (AAS) is a rare condition with multiple congenital anomalies, caused by hemizygote variants in the FGD1 gene. Its description was based mostly on old case reports, in whom a molecular diagnosis was not always available, or on small series. The aim of this study was to better delineate the phenotype and the natural history of AAS and to provide clues for the diagnosis and the management of the patients.Methods: Phenotypic characterisation of the largest reported AAS cohort, comprising 111 male patients with proven causative variants in FGD1, through comprehensive analyses of clinical data including congenital anomalies, growth and neurodevelopment. Review of photographs and radiographs by experts in dysmorphology and skeletal disorders.Results: This study refines the phenotypic spectrum of AAS, with the description of new morphological and radiological features, and refines the prevalence of the features. Short stature is less frequent than previously reported and has a prenatal onset in more than half of the patients. The growth has a specific course with a catch-up during the first decade often leading to low-normal stature in adulthood. Whereas intellectual disability is rare, patients with AAS have a high prevalence of specific learning difficulties and attention hyperactivity disorder. In light of this better knowledge of AAS, we provide management recommendations.Conclusion: A better knowledge of the natural history and phenotypic spectrum of AAS will be helpful for the clinical diagnosis and for the interpretation of FGD1 variants using a retrophenotyping strategy, which is becoming the most common way of diagnosis nowadays. Recommendations for care will improve the management of the patients
Na7[SbW6O24] and K7[SbW6O24], a new type of turn-off luminescence humidity sensors : study of the hydrated forms
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