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Implementing Symmetries of a Free Bose field via White Noise Operators

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Acta Mathematica Sinica,English Series 2003年第1期19卷 147-158页

作者： ShunLongLU0 InstituteofAppliedMathematics AcademyofMathematicsandSystemSciencesChineseAcademyofSciencesBeijing1

Linear symmetries of a free Bose field are exploited in the framework of Hida's white noise functionals triple. General symplectic automorphisms on the single particle space are implemented by generalized operators. the intertwining operators are constructed in a physically intuitive way, characterized analytically in terms of symbols, and factorized into three fundamental parts according to Wick ordering procedure. In particular, the classical Shale's theorem is rederived.

关键词： free Bose field Symplectic automorphisms symbols gaussian Kernel operators Signs and symbols bose white noise

Effects of Plant Residue Decomposition on Soil N Availability,Microbial Biomass and β-Glucosidase Activity During Soil Fertility Improvement in ghana

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Pedosphere 2019年第5期29卷 608-618页

作者： Samuel t. PARtEY Robert B. Z0UGM0RE Naresh V. tHEVAtHASAN Richard F. PREZIOSI CGI AR CCAFS West Africa ProgramInternational Crops Research Institute for the Semi-Arid Tropics (ICRISAT)Bamako B.P. Box 320 (Mali) School of Environmental Sciences University of GuelphGuelph NIG 2W1 (Canada) Faculty of Life Sciences The University of ManchesterManchester M13 9PL (UK)

With limited use of inorganic fertilizers on smallholder farms,plant residues could be viable alternatives for soil fertility *** study was conducted to determine how residue quality and decomposition of nine plant species influence soil N availability,microbial biomass,andβ-glucosidase activity during soil fertility *** differences in N concentration were found among the species,ranging from 12.2 g kg-1 in Zea mays to 39.2 g kg-1 in Baphia *** C/N ratio was the highest in ***(34.4),whereas lignin and polyphenol concentrations were the greatest in Acacia *** highest decomposition rate(0.251%per day)occurred in tithonia diversifolia,and the lowest in ***,Albizia zygia,***,and ***,with the half-lives of 28-56 *** 80%and 89%of N,P,K,Ca,and Mg were released from *** in 7 d,compared with over 70%retention in ***,***,and *** decomposition and nutrient release half-lives of Gliricidia sepium,Leucaena leucocephala,Azadirachta indica,and Senna spectabilis were less than 14 *** mineral N,microbial biomass,andβ-glucosidase activity increased under all treatments,with *** having the greatest *** N mineralization occurred in all of the species throughout the experiment,an initial N immobilization was recorded in the ***,***,***,and *** treatments for up to 14 *** and nutrient release rates,mineral N,soil microbial biomass,andβ-glucosidase activity were dependent on residue quality,and P and lignin levels,the lignin/N ratio,and the(lignin+polyphenol)/N ratio had the most significant effects(P≤0.05).

关键词： leguminous species litter quality microbial activity N mineralization nutrient release organic matter

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A New Approach to Nonlinear Partial Differential Equations

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 230-235页

作者： Jihuan HE (Shanghai University,Shanghai Institute of Applied Mathematics and Mechanics,Shanghai 2 0 0 0 72 ,China) Shanghai University Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 China

In this paper,a novel method called variational iteration method is proposed to solve nonlinear partial differential equations without linearization or small *** this method,a correction functional is constructed by a general Lagrange multiplier,which can be identified via variational *** analytical solution can be obtained from its trial- function with possible unknown constants,which can be identified by imposing the boundary conditions,by successively iteration.

关键词： Nonlinear Problems Partial Differential Equations Variational Iteration Method Variational theory

Valued Gabriel quiver of a wedge product and semiprime coalgebras

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Frontiers of Mathematics in China 2013年第5期8卷 1157-1183页

作者： Gabriel NAVARR0 Department of Computer Sciences and AI University of Granada E1 Greco s/n E-51002Ceuta Spain

We describe the valued Gabriel quiver of a wedge product of coalgebras and study the category of comodules of a semiprime coalgebra. In particular, we prove that any monomial semiprime k-tame fc-tame coalgebra is string. We also prove a version of Eisenbud-Griffith theorem for coalgebras, namely, any hereditary semiprime strictly quasi-finite coalgebra is serial.

关键词： Wedge product semiprime coalgebras representation theory,valued Gabriel quiver

Variational Iteration Method for Delay Differential Equations

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 235-236页

the variational iteration method is shown to be applicable to delay differential equations for analytical approximate solutions

关键词： Variational Iteration Method for Delay Differential Equations

Numerical simulations for G-Brownian motion

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Frontiers of Mathematics in China 2016年第6期11卷 1625-1643页

作者： Jie YANG Weidong ZHA0 School of Mathematics & Finance Institute Shandong University Jinan 250100 China

this paper is concerned with numerical simulations for the G- Brownian motion （defined by S. Peng in Stochastic Analysis and Applications, 2007, 541-567）. By the definition of the G-normal distribution, we first show that the G-Brownian motions can be simulated by solving a certain kind of Hamilton-Jacobi-Bellman （HJB） equations. then, some finite difference methods are designed for the corresponding HJB equations. Numerical simulation results of the G-normal distribution, the G-Brownian motion, and the corresponding quadratic variation process are provided, which characterize basic properties of the G-Brownian motion. We believe that the algorithms in this work serve as a fundamental tool for future studies, e.g., for solving stochastic differential equations （SDEs）/stochastic partial differential equations （SPDEs） driven by the G-Brownian motions.

关键词： Nonlinear expectation G-Brownian motion G-normal distribu- tion Hamilton-Jacobi-Bellman (HJB) equation

Projected area and drag coefficient of high velocity irregular fragments that rotate or tumble

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Defence technology（防务技术） 2017年第4期13卷 269-280页

作者： John F. Moxnes 0yvind Fr0 yland Ivar J. 0ye tom I. Brate Eva Friis Gard 0degardstuen tallak H. Risdal Norwegian Defence Research Establishment Land Systems Division P.O. Box 25 2027 Kjeller Norway Nammo Raufoss AS P.O. Box 162 2831 Raufoss Norway HPVistech AS Bj0rnstadgutua 21 2092 Minnesund Norway

3 degrees of freedom(DOF)exterior ballistic computer models are used in fragment studies to calculate individual trajectories of each fragment based on drag coefficient and the projected(presented)area in the direction of velocity of center of *** expectation of a randomly distributed projected area is commonly used for fragments that tumble(random rotation)during *** forecast a model where the expected drag coefficient is dependent of shape and Mach *** or tumbling only affects the expected projected *** of projected areas during tumbling and rotation are *** examination of the data by Mc Cleskey(1988)indicates that the volume of the fragment to the power of2/3 is a better parameter to characterize the drag coefficient of the fragments than the maximum projected *** simulations are used to verify results and to study projected area and drag coefficient of fragments.

关键词： Fragments Form factor Mach number Drag coefficient Cauchy area tumbling

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Lattice-Boltzmann Models for Heat transfer

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 212-216页

作者： Chenghai SUN,Zujun XU,Baoguo WANG &Mengyu SHEN (Dept. of Engineering Mechanics,tsing- hua University,Beijing,1 0 0 0 84) Department of Engineering Mechanics Tsinghua University Beijing 100084 China

A multispeed heat transfer lattice Boltzmann model is presented. the model possesses the perfect gas state equation with arbitrary special heat ratio. the macroscopic conservation equations are derived by the Chapman- Enskog *** one dimensional simulation for the sinusoidal energy distributions are compared with the theoretical results, showing good *** theoretical conductivity in the energy equation is in accordance with the simulations.

关键词： Lattice Boltzmann heat transfer perfect gas

Classification of hypersurfaces with two distinct principal curvatures and closed Mbius form in S^(m+1)

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Science China Mathematics 2012年第7期55卷 1463-1478页

作者： LINLiMiao GU0Zhen DepartmentofMathematics EastChinaNormalUniversityShanghai200241China DepartmentofMathematics YunnanNormalUniversityKunming650092China

Let x be an m-dimensional umbilic-free hypersurface in an （m＋1）-dimensional unit sphere Sm＋l （m≥3）. In this paper, we classify and explicitly express the hypersurfaces with two distinct princi- pal curvatures and closed MSbius form, and then we characterize and classify conformally flat hypersurfaces of dimension larger than 3.

关键词： moebius geometry principal curvature conformally fiat MSbius form

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