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一种连续介质单元转化为颗粒流的方法及其在岩土工程中的应用

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一种连续介质单元转化为颗粒流的方法及其在岩土工程中的应用

Fast prediction of rain erosion in wind turbine blades using a data-based computational tool

中国力学大会——2013

作者： Feng Chun Li Shihai eugenio onate Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of Sciences International Centre for Numerical Methods in Engineering Universitat Politecnica de Catalunya

连续介质单元在分析材料弹塑性变形方面具有优势,而颗粒流则适合模拟材料的失稳断裂及摩擦滑移过程。为了充分发挥两者的优势,文章提出了一种连续介质单元转化为颗粒流的方法。该方法采用显式求解方式,将研究区域用连续介质单元(FEM单元...

连续介质单元在分析材料弹塑性变形方面具有优势,而颗粒流则适合模拟材料的失稳断裂及摩擦滑移过程。为了充分发挥两者的优势,文章提出了一种连续介质单元转化为颗粒流的方法。该方法采用显式求解方式,将研究区域用连续介质单元(FEM单元)进行离散,并在每个单元上引入强度随塑性应变弱化的Mohr-Coulomb模型及最大拉应力模型;计算中当某个单元的黏聚力或抗拉强度减小为零时,认为该单元已达到破坏状态,将其删除

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Journal of Hydrodynamics 2024年第3期36卷 504-518页

作者： Juan M.Gimenez Sergio R.Idelsohn eugenio Oñate Centre Internacional de Mètodes Numèrics en Enginyeria(CIMNE) Edifici C1 Campus Nord UPC C/Gran CapitàS/NBarcelonaSpain

Wind turbines(WTs)face a high risk of failure due to environmental factors like erosion,particularly in high-precipitation areas and offshore *** this paper we introduce a novel computational tool for the fast prediction of rain erosion damage on WT blades that is useful in operation and maintenance decision making *** approach is as follows:Pseudo-Direct Numerical Simulation(P-DNS)simulations of the droplet-laden flow around the blade section profile are employed to build a high-fidelity data set of impact statistics for potential operating *** this database as training data,a machine learning-based surrogate model provides the feature of the impact pattern over the 2-D section for given wind and rain *** this information,a fatigue-based model estimates the remaining lifetime and erosion damage for both homogeneous and coating-substrate blade *** prediction is done by quantifying the accumulated droplet impact energy and evaluating operative conditions over time periods for which the weather at the installation site is *** this work,we describe the modules that compose the prediction method,namely the database creation,the training of the surrogate model and their coupling to build the prediction ***,the method is applied to predict the remaining lifetime and erosion damage to the blade sections of a reference *** evaluate the reliability of the tool,several site locations(offshore,coastal,and inland),the coating material and the coating thickness of the blade are *** few minutes we are able to estimate erosion after many years of *** results are in good agreement with field observations,showing the promise of the new rain erosion prediction approach.

关键词： Wind turbine blades leading edge erosion fatigue Pseudo-Direct Numerical Simulation(P-DNS) machine learning eblader

Spatial and temporal patterns of forest fires in the Central Monte:relationships with regional climate

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Ecological Processes 2024年第01期13卷 66-79页

作者： Pablo eugenio Villagra Erica Cesca Leandro Manuel Alvarez Silvia Delgado Ricardo Villalba Instituto Argentino de Nivología Glaciología y Ciencias Ambientales–CONICET-CCT Mendoza Facultad de Ciencias Agrarias Universidad Nacional de Cuyo

Background Natural and anthropogenic wildfires burn large areas of arid and semi-arid forests with significant socio-economic and environmental impacts. Fire regimes are controlled by climate, vegetation type, and anthropogenic factors such as ignition sources and human-induced disturbances. Projections of climate and land-use change suggest that these controlling factors will change, altering fire regimes in the near future. In the southern Central Monte, Mendoza, Argentina, the factors that modulate the fire temporal and spatial variability are poorly understood. We reconstructed the fire history of southeast of Mendoza from 1984 to 2023 and investigated the relationships between fire extent and climate variability at seasonal and interannual scales. Burned areas were determined using Google Earth Engine by processing Landsat 5-TM, Landsat 7-ETM+, and Landsat 8-OLI-TIRS sensor *** The region exhibited high spatial and temporal variability in fire occurrence, being a mosaic of areas with different fire histories and recovery times. Between 1985 and 2023, fire recurrence ranged from sites unburned to sites with up to 14 fires. The occurrence of large fires was strongly favored by a combination of a year with abundant spring–early summer precipitation, which favors fuel accumulation, followed by a year of low spring–early summer precipitation. Precipitation and burnt area showed a very pronounced 6–7 year cycle, suggesting a dominant climatic control on fire *** Fire distribution in southeastern Mendoza forests is not homogeneous, resulting in a mosaic of patches with different fire histories. This heterogeneity may be related to vegetation patterns and land use. The temporal variability of fires is strongly influenced by climate variability, which would promote fuel production and subsequent drying. Large fires are concentrated in periods of high interannual precipitation variability. Climate change scenarios predict an increase in tem

关键词： Fire recurrence Fire mapping Recovery time Climate Dry forest Wildfire

Time and Space Efficient Multi-Model Convolution Vision Transformer for Tomato Disease Detection from Leaf Images with Varied Backgrounds

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Computers, Materials & Continua 2024年第4期79卷 117-142页

作者： Ankita Gangwar Vijaypal Singh Dhaka Geeta Rani Shrey Khandelwal Ester Zumpano eugenio Vocaturo Department of Computer and Communication Engineering Manipal University JaipurJaipurIndia Department of IoT and Intelligent Systems Manipal University JaipurJaipurIndia Department of Computer Engineering ModellingElectronics and Systems(DIMES)University of CalabriaRende(Cosenza)Italy National Research Council Institute of Nanotechnology(NANOTEC)Rende(Cosenza)Italy

A consumption of 46.9 million tons of processed tomatoes was reported in 2022 which is merely 20%of the total *** increase of 3.3%in consumption is predicted from 2024 to *** are also rich in iron,potassium,antioxidant lycopene,vitamins A,C and K which are important for preventing cancer,and maintaining blood pressure and glucose ***,tomatoes are globally important due to their widespread usage and nutritional *** face the high demand for tomatoes,it is mandatory to investigate the causes of crop loss and minimize *** are one of the major causes that adversely affect crop yield and degrade the quality of the tomato *** leads to financial losses and affects the livelihood of ***,automatic disease detection at any stage of the tomato plant is a critical *** learning models introduced in the literature show promising results,but the models are difficult to implement on handheld devices such as mobile phones due to high computational costs and a large number of ***,most of the models proposed so far work efficiently for images with plain backgrounds where a clear demarcation exists between the background and leaf ***,the existing techniques lack in recognizing multiple diseases on the same *** address these concerns,we introduce a customized deep learning-based convolution vision transformer *** achieves an accuracy of 93.51%for classifying tomato leaf images with plain as well as complex backgrounds into 13 *** requires a space storage of merely 5.8 MB which is 98.93%,98.33%,and 92.64%less than stateof-the-art visual geometry group,vision transformers,and convolution vision transformermodels,*** training time of 44 min is 51.12%,74.12%,and 57.7%lower than the above-mentioned ***,it can be deployed on(Internet of Things)IoT-enabled devices,drones,or mobile devices to assist farmers in the real-time monitoring of tomato *** p

关键词： Tomato disease transformer deep learning mobile devices

Virtual Transmission Solution Based on Battery Energy Storage Systems to Boost Transmission Capacity

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 466-474页

作者： Matías Agüero Jaime Peralta eugenio Quintana Victor Velar Anton Stepanov Hossein Ashourian Jean Mahseredjian Roberto Cárdenas Coordinador Eléctrico Nacional SantiagoChile PGSTech Montreal Canada Ecole Polytechnique de Montréal Montréal Canada University of Chile Santiago Chile IEEE

The increasing penetration of variable renewable energy(VRE)generation along with the decommissioning of conventional power plants in Chile,has raised several operational challenges in the Chilean National Power Grid(NPG),including transmission congestion and VRE *** mitigate these limitations,an innovative virtual transmission solution based on battery energy storage systems(BESSs),known as grid booster(GB),has been proposed to increase the capacity of the main 500 kV corridor of the *** paper analyzes the dynamic performance of the GB using a wide-area electromagnetic transient(EMT)model of the *** GB project,composed of two 500 MVA BESS units at each extreme of the 500 kV corridor,allows increasing the transmission capacity for 15 min during N-1 contingencies,overcoming transmission limitations under normal operation conditions while maintaining system stability during *** dynamic behavior of the GB is also analyzed to control power flow as well as voltage *** results show that the GB is an effective solution to allow greater penetration of VRE generation while maintaining system stability in the NPG.

关键词： Battery energy storage system(BESS) grid booster transient stability voltage stability electromagnetic transient(EMT)

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Trio in a Triangle

China Today 2024年第2期73卷 21-23页

作者： eugenio BREGOLAT 不详

Europe should use its moderating power to prevent *** from spiralling into open confrontation.W HEREVER we look,understanding and cooperation among states is indispensable,be it to keep peace in the world,maintain economic progress or confront global challenges beginning with climate change and ending with artificial *** between the two great powers of our time,the United States and China,is of the essence.

关键词： peace maintain artificial

The formation and growth mechanisms of young back-arc spreading ridges from high-resolution bathymetry:The Marsili Seamount(Tyrrhenian Sea,Italy)

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Geoscience Frontiers 2024年第1期15卷 325-338页

作者： eugenio Nicotra Salvatore Passaro Guido Ventura Dipartimento di Biologia Ecologia e Scienze della Terra Universitàdella Calabria87036 Arcavacata di RendeCosenzaItaly Istituto di Scienze Marine CNR 80133 NapoliItaly Istituto Nazionale di Geofisica e Vulcanologia 00143 RomaItaly Istituto per lo Studio degli impatti Antropici e Sostenibilitáin ambiente marino CNR 91026 Capo GranitolaTrapaniItaly

The formation and growth mechanisms of Mid-Ocean Ridges(MOR)are relatively well known,whereas those of back-arc spreading ridges are comparatively less known because geophysical,geochemical,and morphological data are scarce and of low *** we present a high-resolution bathymetry of the Marsili Seamount(MS;1 Ma-3 ka),which represents the inflated spreading ridge of the 2 Ma old Marsili back-arc basin associated to the subduction of the Ionian Sea below the Calabrian Arc and Tyrrhenian *** is 70 km long,30 km wide,and its height reaches about 3000 m from surrounding *** new digital bathymetric model has a 5 m grid cell size resolution and covers the MS bathymetry from-1670 mbsl to the top at-491 *** conduct morphometric and morphological analyses of the bathymetry and recognize landforms due to volcanic,tectonic,hydrothermal and gravity *** consists of volcanoes related to fissural and central-type activity,this latter located at the northern and southern tips of the main dike *** swarms represent the surface expression of different ridge segments whose strikes are controlled by the larger scale back-arc spreading processes and by the local occurrence of an active hydrothermal *** latter develops in a flat area between two partly overlapping ridge segments where historical volcanism and extensional processes *** ridges represent the embryonic stage of the formation of transform-like *** volcanoes,the northern of which is characterized by a caldera,form at the tips of MS because the decrease in width of the major volcanic fissures promotes vent localization associated with the formation of sill-like reservoirs from which central-type vents may *** processes affecting the MS flanks are due to shallow seafloor *** collapses affecting the northernmost central-type polygenic volcano must be included in the evaluation of the hazard related to potential *** dipping faul

关键词： Back-arc spreading ridge Morphology Tectonics Volcanism Marsili seamount

Brain insulin resistance: an early risk factor for Alzheimer's disease development in Down syndrome

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Neural Regeneration Research 2022年第2期17卷 333-335页

作者： eugenio Barone Department of Biochemical Sciences“A.Rossi-Fanelli” Sapienza University of RomePiazzale A.MoroRomaItaly

Down syndrome(DS) is the most frequent chromosomal abnormality that causes intellectual disability, resulting from the presence of an extra complete or segment of chromosome 21(HSA21)(Tramutola et al., 2020;Lanzillotta et al., 2021). Every year, approximately 6000 children are born with DS and most of them do not have an autonomous life.

关键词： al. Alzheimer Down

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Computing Open-Loop Optimal Control of the q-Profile in Ramp-Up Tokamak Plasmas Using the Minimal-Surface Theory

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Plasma Science and Technology 2013年第5期15卷 403-410页

作者：许超欧勇盛 eugenio SCHUSTER 于欣 The State Key Laboratory of Industrial Control Technology Zhejiang University Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Department of Mechanical Engineering & Mechanics Lehigh University Ningbo Institute of Technology Zhejiang University

The q-profile control problem in the ramp-up phase of plasma discharges is consid- ered in this work. The magnetic diffusion partial differential equation （PDE） models the dynamics of the poloidal magnetic flux profile, which is used in this work to formulate a PDE-constrained op-timization problem under a quasi-static assumption. The minimum surface theory and constrained numeric optimization are then applied to achieve suboptimal solutions. Since the transient dy- namics is pre-given by the minimum surface theory, then this method can dramatically accelerate the solution process. In order to be robust under external uncertainties in real implementations, PID （proportional-integral-derivative） controllers are used to force the actuators to follow the computational input trajectories. It has the potential to implement in real-time for long time discharges by combining this method with the magnetic equilibrium update.

关键词： advanced plasma operations current profile dynamics optimal control theory,minimal surface equation differential geometry

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