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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

Assessment of ship manoeuvrability by using a coupling between a nonlinear transient manoeuvring model and mathematical programming techniques

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Journal of Hydrodynamics 2013年第5期25卷 788-804页

作者： TRAN KHANH Toan OUAHSINE Abdellatif NACEUR Hakim EL WASSIFI Karima laboratoire Roberval Université de Technologie de Compiègne laboratoire LAMIH Université de Valenciennes Université Cadi Ayyad Faculté des Sciences et Techniques

In this paper, a numerical method based on a coupling between a mathematical model of nonlinear transient ship manoeuvring motion in the horizontal plane and Mathematical Programming （MP） techniques is proposed. The aim of the proposed procedure is an efficient estimation of optimal ship hydrodynamic parameters in a dynamic model at the early design stage. The proposed procedure has been validated through turning circle and zigzag manoeuvres based on experimental data of sea trials of the 190 000- dwt oil tanker. Comparisons between experimental and computed data show a good agreement of overall tendency in manoeuvring traiectories.

关键词： ship manoeuvrability hydrodynamics coefficients nonlinear transient dynamics sensitivity analysis mathematical pro- gramming

Direct oxidation of methane to oxygenates over heteropolyanions

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Journal of Natural Gas Chemistry 2008年第3期17卷 309-312页

作者： Ouarda Benlounes Sadia Mansouri Chérifa Rabia Smain Hocine laboratoire de Chimie Appliqueé et de Génie Chimique Université Mouloud Mammeri laboratoire de Chimie du Gaz Naturel Institut de Chimie USTHB

Partial oxidation of methane to formaldehyde and methanol was studied at atmospheric pressure in the temperature range of 700-750 °C using heteropolycompound catalysts （NH4）6HSiMo11FeO40, （NH4）4PMo11FeO39, and H4PMo11VO40, which were prepared and characterized by various analysis techniques such as infrared, visible UV, XRD and DTA. O2 or N2O was used as the oxidizing agent, and the principal products of the reaction were CH3OH, CH2O, CO, CO2, and water. The conversion and the selectivity of products depend strongly on the reaction temperature, the nature of oxidizing agent, and the composition of catalyst.

关键词： methane oxidation heteropolycompounds methanol oxygenates

Oscillatory flow of second grade fluid in cylindrical tube

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Applied mathematics and Mechanics(English Edition) 2013年第9期34卷 1097-1106页

作者： A.ALI S.ASGHAR H.H.ALSULAMI laboratoire Jean Alexandre Dieudonne Universite de Nice Sophia Antipolis department of mathematics Commission on Science and Technology for Sustainable Development in the SouthInstitute of Information Technology department of mathematics King Abdulaziz University

The unsteady oscillatory flow of an incompressible second grade fluid in a cylindrical tube with large wall suction is studied analytically. Flow in the tube is due to uniform suction at the permeable walls, and the oscillations in the velocity field are due to small amplitude time harmonic pressure waves. The physical quantities of interest are the velocity field, the amplitude of oscillation, and the penetration depth of the oscillatory wave. The analytical solution of the governing boundary value problem is obtained, and the effects of second grade fluid parameters are analyzed and discussed.

关键词： second grade fluid cylindrical coordinate oscillatory flow incompressible flow laminar flow Navier-Stokes equation partial differential equation Wentzel- Kramers-Brillouin (WKB) approximation

The periodic unfolding method for the heat equation in perforated domains

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Science China mathematics 2016年第5期59卷 891-906页

作者： DONATO Patrizia YANG ZhanYing laboratoire de Mathématiques Raphael Salem Normandie Université Université de Rouen Saint Etienne de Rouvray 76801 France department of mathematics South-Central University for Nationalities Wuhan 430074 China

We study the heat equation with non-periodic coefficients in periodically perforated domains with a homogeneous Neumann condition on the holes. Using the time-dependent unfolding method, we obtain some homogenization ... 详细信息

关键词： heat equations perforated domains homogenization correctors periodic unfolding method

The xanthate route to all-carbon quaternary centers

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Science China Chemistry 2019年第11期62卷 1450-1462页

作者： Béatrice Quiclet-Sire Samir Z.Zard laboratoire de Synthèse Organique Ecole Polytechnique

This review discusses the numerous routes to all-carbon quaternary centers based on the unique radical chemistry of xanthates. Itsummarizes the various approaches to the synthesis of tertiary xanthates then describes the intra- and intermolecular radicaladditions and combinations thereof that have so far been used to construct quaternary centers.

关键词： xanthates quaternary centers radical addition cyclization tandem reactions

NOTES ON REAL INTERPOLATION OF OPERATOR L_(p)-SPACES

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Acta Mathematica Scientia 2021年第6期41卷 2173-2182页

作者： Marius JUNGE Quanhua XU department of mathematics University of IllinoisUrbanaIL61801USA Institute for Advanced Study in mathematics Harbin Institute of TechnologyHarbin150001China laboratoire de Mathématiques Universitéde Bourgogne Franche-Comté25030Besançon CedexFrance

Let M be a semifinite von Neumann *** equip the associated noncommutative Lp-spaces with their natural operator space structure introduced by Pisier via complex *** the other hand,for L_(p),p(M)=(L_(∞)(M),L_(1)(M)_(1/p,p)be equipped with the operator space structure via real interpolation as defined by the second named author(***.139(1996),500–539).We show that Lp,p(M)=Lp(M)completely isomorphically if and only if M is finite *** solves in the negative the three problems left open in the quoted work of the second *** also show that for 1

关键词： operator spaces L_(p)-spaces real interpolation column Hilbertian spaces

On Non-Abelian Extensions of 3-Lie Algebras

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Communications in Theoretical Physics 2018年第4期69卷 347-356页

作者： Li-Na Song Abdenacer Makhlouf Rong Tang department of mathematics Jilin University Changchun 130012 China University of Haute Alsace Laboratoire de Math~matiques Informatique et Applications Mulhouse France

In this paper, we study non-abelian extensions of 3-Lie algebras through Maurer-Cartan elements. We show that there is a one-to-one correspondence between isomorphism classes of non-abelian extensions of 3-Lie algebras and equivalence classes of Maurer-Cartan elements in a DGLA. The structure of the Leibniz algebra on the space of fundamental objects is also analyzed.

关键词： 3-Lie algebras Leibniz algebra non-abelian extension Maurer-Cartan element

Dispersive Blow-Up Ⅱ.Schrdinger-Type Equations,Optical and Oceanic Rogue Waves

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Chinese Annals of mathematics,Series B 2010年第6期31卷 793-818页

作者： Jerry L.BONA Jean-Claude SAUT department of mathematics Statistics and Computer Science University of Illinois at Chicago laboratoire de Mathématiques UMR 8628 Université Paris-Sud et CNRS

Addressed here is the occurrence of point singularities which owe to the focusing of short or long waves, a phenomenon labeled dispersive blow-up. The context of this investigation is linear and nonlinear, strongly dispersive equations or systems of equations. The present essay deals with linear and nonlinear Schrdinger equations, a class of fractional order Schrdinger equations and the linearized water wave equations, with and without surface tension. Commentary about how the results may bear upon the formation of rogue waves in fluid and optical environments is also included.

关键词： Rogue waves Dispersive blow-up Nonlinear dispersive equations Nonlinear Schrdinger equation Water wave equations Propagation in optical cables Weak turbulence models