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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien G.Moreau jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

Corrections to the scaling of the second-order structure function in isotropic turbulence

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Acta Mechanica Sinica 2010年第2期26卷 151-157页

作者： Le Fang Wouter j. T. Bos Xiaozhou Zhou Liang Shao j.an-pierre bertoglio Laboratoire de Mecanique des Fluides et d'Acoustique Universit6 de Lyon Ecole centrale de Lyon 69134 Ecully France Department of Mechanical Engineering Center for Biomedical Engineering Research University of Delaware 126 Spencer Laboratory Newark DE 19716 USA

The approach of Obukhov assuming a constant skewness was used to obtain analytical corrections to the scaling of the second order structure function, starting from Kolmogorov＇s 4/5 law. These corrections can be used in model applications in which explicit expressions, rather than numerical solutions are needed. The comparison with an interpolation formula proposed by Batchelor, showed that the latter gives surprisingly precise results. The modification of the same method to obtain analytical corrections to the scaling law, taking into account the possible corrections induced by intermittency, is also proposed.

关键词： Scaling law · Structure function ·Isotropic turbulence

Comparison of Two Recurrent Neural Networks for Rainfall-Runoff Modeling in the Zou River Basin at Atchérigbé (Bénin)

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journal of Geoscience and Environment Protection 2024年第9期12卷 167-181页

作者： Iboukoun Eliézer Biao Oscar Houessou pierre jérôme Zohou Adéchina Eric Alamou National School of Mathematical Engineering and Modeling National University of Sciences Technology Engineering and Mathematics Abomey Benin LaGEA National School of Public Works National University of Sciences Technology Engineering and Mathematics Abomey Benin International Chair of Mathematical Physics and Applications (ICMPA-UNESCO Chair) University of Abomey-Calavi Abomey-Calavi Bnin

Hydrological models are developed to simulate river flows over a watershed for many practical applications in the field of water resource management. The present paper compares the performance of two recurrent neural networks for rainfall-runoff modeling in the Zou River basin at Atchérigbé outlet. To this end, we used daily precipitation data over the period 1988-2010 as input of the models, such as the Long Short-Term Memory (LSTM) and Recurrent Gate Networks (GRU) to simulate river discharge in the study area. The investigated models give good results in calibration (R2 = 0.888, NSE = 0.886, and RMSE = 0.42 for LSTM;R2 = 0.9, NSE = 0.9 and RMSE = 0.397 for GRU) and in validation (R2 = 0.865, NSE = 0.851, and RMSE = 0.329 for LSTM;R2 = 0.9, NSE = 0.865 and RMSE = 0.301 for GRU). This good performance of LSTM and GRU models confirms the importance of models based on machine learning in modeling hydrological phenomena for better decision-making.

关键词： Supervised Learning Modeling Zou Basin Long and Short-Term Memory Gated Recurrent Unit Hyperparameters Optimization

Recent understanding on the subgrid-scale modeling of large-eddy simulation in physical space

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Science China(Physics,Mechanics & Astronomy) 2014年第12期57卷 2188-2193页

作者： FANG Le SHAO Liang bertoglio j.-P. Laboratory of Mathematics and Physics Ecole Centrale de P'ekin Beijing University of Aeronautics and Astronautics Laboratoire de M'ecaniques des Fluides et d'Acoustique Ecole Centrale de Lyon

In the last 50 years,the methodology of large-eddy simulation(LES)has been greatly developed,while lots of different subgridscale(SGS)models have ***,the understanding of the procedure of SGS modeling is still not *** present contribution aims at reviewing the recent SGS models and,more importantly,expressing our recent understanding on the SGS modeling of LES in physical *** the Kolmogorov equation for filtered quantities(KEF)as an example,it is argued that the KEF alone is not enough to be a closure *** physical laws are then introduced to complete this closure procedure and are expected to inspire the future researches of SGS modeling.

关键词： large-eddy simulation subgrid-scale modeling Koimogorov equation

TRANSPORTATION OF PASSIVE SCALAR IN INHOMOGENEOUS TURBULENCE

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Acta Mechanica Sinica 2000年第1期16卷 21-28页

作者：崔桂香陈宇光张兆顺许春晓 L.Shao j.P.bertoglio Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China Laboratory of Fluid Mechanics and Acoustics Ecole Centrale de LyonFrance

The paper studies the transportation of passive scalar in the inhomogeneous turbulence by means of large eddy simulation. The prediction accuracy is verified by the well-known Comte-Bellot spectrum of the homogeneous turbulence. The mean transportation properties are predicted with satisfaction and the underestimation of the thermal flux by the phenomenological models has been disclosed. The high intermittence of the temperature fluctuations has been found in the inhomogeneous turbulence and it is the reason for the underestimation of turbulent thermal flux by the phenomenological model.

关键词： turbulence passive scalar large eddy simulation

Effects of plane strain on inhomogeneous turbulence

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Science China Mathematics 1999年第2期42卷 154-161页

作者：张兆顺崔桂香许春晓 L.SHAO H.Pascal j.P.bertoglio LMFA UMR CNRS 5509 Ecole Centrale de Lyon Ecole Centrale de Lyon Ecully Ecully Ecully

The influence of the mean plane strain on the turbulence transportation is investigated by large eddy simulation (LES) in the shearless turbulence mixing layer. It is found that the mean strains enhance the turbulent fluctuations in the mixing region. Compression in the inhomogeneous direction can greatly increase the transport of turbulent kinetic energy by triple correlation terms, while stretching in the inhomogeneous direction decreases the turbulence transportation. The gradient diffusion models for turbulent transportation are evaluated and it is found that the inter-mittency consideration can improve the prediction ability of the gradient-type models for the triple correlation terms.

关键词： shearless turbulence mixing layer large eddy simulation.

Two-phase flow distributors for fuel cell flow channels

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Particuology 2010年第6期8卷 582-587页

作者： Hsiaotao T.Bi pierre Sauriol jürgen Stumper Clean Energy Research Centre and Department of Chemical and Biological Engineering University of British ColumbiaVancouverBCCanadaV6T 1Z4 Automotive Fuel Cell Corporation BurnabyBCCanadaV5J 5J8

All existing proton exchange membrane （PEM） fuel cell gas flow fields have been designed on the basis of single-phase gas flow distribution. The presence of liquid water in the flow causes non-uniform gas distribution, leading to poor cell performance. This paper demonstrates that a gas flow restrictor/distributor, as is commonly used in two-phase flow to stabilize multiphase transport lines and multiphase reactors, can improve the gas flow distribution by significantly reducing gas real-distribution caused by either non-uniform water formation in parallel flow channels or flow instability associated with negative-slope pressure drop characteristic of two-phase horizontal flow systems.

关键词： Gas distributor Gas-liquid two-phase flow Fuel cell flow field Pressure drop hysteresis Flow real-distribution

Challenges and prospects for consumer acceptance of cultured meat

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journal of Integrative Agriculture 2015年第2期14卷 285-294页

作者： Wim Verbeke pierre Sans Ellen j Van Loo Department of Agricultural Economics Ghent UniversityGent B-9000 Belgium INP-ENV Toulouse Toulouse 31076 France UR1303 ALISS INRA Ivry-sur-Seine 94205 France

Consumer acceptance of cultured meat is expected to depend on a wide diversity of determinants ranging from technologyrelated perceptions to product-specific expectations, and including wider contextual factors like media coverage, public involvement, and trust in science, policy and society. This paper discusses the case of cultured meat against this multitude of possible determinants shaping future consumer acceptance or rejection. The paper also presents insights from a primary exploratory study performed in April 2013 with consumers from Flanders（Belgium）（n=180）. The concept of cultured meat was only known（unaided） by 13% of the study participants. After receiving basic information about what cultured meat is, participants expressed favorable expectations about the concept. Only 9% rejected the idea of trying cultured meat, while two thirds hesitated and about quarter indicated to be willing to try it. The provision of additional information about the environmental benefits of cultured meat compared to traditional meat resulted in 43% of the participants indicating to be willing to try this novel food, while another 51% indicated to be ‘maybe＇ willing to do so. Price and sensory expectations emerged as major obstacles. Consumers eating mostly vegetarian meals were less convinced that cultured meat might be healthy, suggesting that vegetarians may not be the ideal primary target group for this novel meat substitute. Although exploratory rather than conclusive, the findings generally underscore doubts among consumers about trying this product when it would become available, and therefore also the challenge for cultured meat to mimic traditional meat in terms of sensory quality at an affordable price in order to become acceptable for future consumers.

关键词： acceptance artificial attitude consumer cultured in vitro meat synthetic

Solving the Dyson-Schwinger equation around its first singularities in the Borel plane

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Frontiers of physics 2016年第6期11卷 25-30页

作者： Clavier, pierre j. Bellon, Marc P. Sorbonne Universites UPMC Univ Paris 06 UMR 7589 LPTHE Paris France CNRS UMR 7589 LPTHE Paris France

The Dyson-Schwinger equation of the massless Wess-Zumino model is written as an equation over the anomalous dimension of the theory. Its asymptotic behavior is derived and the procedure to compute the perturbations of this asymptotic behavior is detailed. This procedure uses ill-defined objects. To solve this, the Dyson-Schwinger equation is rewritten for the Borel plane. It is shown that the ill- defined procedure in the physical plane can be applied in the Borel plane. Other results obtained in the Borel plane are stated and the proof for one result is described.

关键词： Dyson-Schwinger equation Wess-Zumino model Borel transform

This work was supported by the European Research Council Advanced Grant(ETAP-742985 to *** j.F.)and by the Ministry of Science and Technology(grant 110-2636-B-005-001 to K.-j.L.).

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Plant Communications 2024年第1期5卷 130-147页

作者： Yu Zhang Yuan Fu Wenfei Xian Xiuli Li Yong Feng Fengjiao Bu Yan Shi Shiyu Chen Robin van Velzen Kai Battenberg Alison M.Berry Marco G.Salgado Hui Liu Tingshuang Yi Pascale Fournier Nicole Alloisio Petar Pujic Hasna Boubakri M.Eric Schranz pierre-Marc Delaux Gane Ka-Shu Wong Valerie Hocher Sergio Svistoonoff Hassen Gherbi Ertao Wang Wouter Kohlen Luis G.Wall Martin Parniske Katharina Pawlowski Philippe Normand jeffrey j.Doyle Shifeng Cheng Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518124China Biosystematics Group Department of Plant SciencesWageningen University6708PB Wageningenthe Netherlands Department of Plant Sciences University of CaliforniaDavisDavisCA 95616USA Department of Ecology Environment and Plant SciencesStockholm University10691 StockholmSweden Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesLanhei RoadKunming 650201China Universite´de Lyon Universite´Lyon 1CNRSUMR5557Ecologie MicrobienneINRAUMR 141843 bd du 11 novembre 191869622 VilleurbanneFrance Laboratoire de Recherche en Sciences Ve´ge´tales(LRSV) Universite´de ToulouseCNRSUPS24 chemin de Borde RougeAuzevilleBP4261731326 Castanet TolosanFrance Department of Biological Sciences University of AlbertaEdmontonAB T6G 2E9Canada French National Research Institute for Sustainable Development(IRD) UMR LSTM(IRD/CIRAD/INRAe/Montpellier University/Supagro)-Campus International BaillarguetTA A-82/J34398 Montpellier Cedex 5France National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologySIBSChinese Academy of SciencesShanghaiChina Laboratory of Molecular Biology Department of Plant SciencesWageningen University6708PB Wageningenthe Netherlands Laboratory of Biochemistry Microbiology and Soil Biological InteractionsDepartment of Science and TechnologyNational University of QuilmesCONICETBernalArgentina Faculty of Biology GeneticsLMU MunichGroßhaderner Strasse 2-482152 MartinsriedGermany School of Integrative Plant Science Sections of Plant Biology and Plant Breeding&GeneticsCornell UniversityIthacaNY 14853USA State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China Univer

Plant root-nodule symbiosis(RNS)with mutualistic nitrogen-fixing bacteria is restricted to a single clade of angiosperms,the Nitrogen-Fixing Nodulation Clade(NFNC),and is best understood in the legume *** species share many commonalities,explained either by divergence from a common ancestor over 100 million years ago or by convergence following independent origins over that same time ***,comparative analyses of diverse nodulation syndromes can provide insights into constraints on nodulation—what must be acquired or cannot be lost for a functional symbiosis—and the latitude for Plant Communications Genomic landscape of nodulation variation in the ***,much remains to be learned about nodulation,especially outside of ***,we employed a large-scale phylogenomic analysis across 88 species,complemented by 151 RNA-seq libraries,to elucidate the evolution of *** phylogenomic analyses further emphasize the uniqueness of the transcription factor NIN as a master regulator of nodulation and identify key muta-tions that affect its function across the *** transcriptomic assessment revealed nodule-specific upregulated genes across diverse nodulating plants,while also identifying nodule-specific and nitrogen-response *** 70%of symbiosis-related genes are highly conserved in the four representative species,whereas defense-related and host-range restriction genes tend to be lineage *** study also identified over 900000 conserved non-coding elements(CNEs),over 300000 of which are unique to sampled NFNC ***-specific CNEs are enriched with the active H3K9ac mark and are correlated with accessible chromatin regions,thus representing a pool of candidate regula-tory elements for genes involved in ***,our results provide novel insights into the evolution of nodulation and lay a foundation for engineering of RNS traits in agriculturally important crops.

关键词： nitrogen-fixing root-nodule symbiosis two competing hypotheses phylogenomics phylotranscrip-tomics conserved non-coding elements convergence deep homology