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Simulation of Lagrangian dispersion using a Lagrangian stochastic model and DNS in a turbulent channel flow

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Simulation of Lagrangian dispersion using a Lagrangian stoch...

第二十一届全国水动力学研讨会暨第八届全国水动力学学术会议暨两岸船舶与海洋工程水动力学研讨会

作者： LUO jian-ping~1 QIU xiang~2 LU Zhi-ming~2 LIU Yu-lu~(1,2) (1.Shanghai Institute of Technology,Shanghai,200235 2.Shanghai Institute of Applied Mathematics and Mechanics,Shanghai University,Shanghai,200072)

Dispersion of fluid particles in a turbulent channel flow is investigated using a modified Langevin equation,and is compared with DNS results at Re=100.A direct numerical simulation of turbulent channel flow at a low Reynolds number was performed to evaluate the velocities and trajectories of fluid particles;The pseudo-spectral numerical scheme was used in this *** domain size in the streamwise,wall-normal,and spanwise directions is 1880×200×630 in wall units, respectively. Both the Lagrangian integral time scale directly obtained from DNS and the predicted value from the Eulerian integral time scale of DNS using the empirical relationship between the Eulerian and the Lagrangian integral time scales are used in the modified Langavin model to test the effect of integral scale on the *** results show that the slight variation of the Lagrangian integral time scale has little influence on the *** agreement between results of the model equation and those of DNS is satisfactory except the streamwise dispersion for intermediate times (20

关键词： Turbulent Channel Flow Langevin equation DNS Lagrangian dispersion

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高精度太阳位置算法及在太阳能发电中的应用

水电能源科学 2008年第2期26卷 201-204页

作者：马健向平西北工业大学机电学院陕西西安710072

在主动式跟踪太阳能发电系统中,要求精确计算太阳位置以实现跟踪并提高发电效率。根据JeanMeeus《天文算法》计算天体的方法给出了计算太阳位置的具体方法,得出太阳位置的累计误差不超过±0.000 3°,完全满足太阳跟踪的需要。应用此算... 详细信息

在主动式跟踪太阳能发电系统中,要求精确计算太阳位置以实现跟踪并提高发电效率。根据JeanMeeus《天文算法》计算天体的方法给出了计算太阳位置的具体方法,得出太阳位置的累计误差不超过±0.000 3°,完全满足太阳跟踪的需要。应用此算法计算了太阳赤经和赤纬,并对结果进行了比较。太阳能发电应用实例表明,该方法计算精度高,误差小,易编程。

关键词：太阳能太阳赤经太阳赤纬水平角高度角

技术调节理论视野下的“师-技”关系及其实践指向

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黑龙江高教研究 2025年第1期43卷 118-123页

作者：周建平绍兴文理学院浙江绍兴312000

从技术调节理论看,“师-技”关系本质上是一种“共塑”关系。在教师使用技术情境中,教师与技术相互形塑,不仅技术调节着教师的经验和行动,而且教师也在“处置”、重构乃至重塑技术。“共塑”论不仅拒斥“替代论”、消除“恐惧论”,而且... 详细信息

从技术调节理论看,“师-技”关系本质上是一种“共塑”关系。在教师使用技术情境中,教师与技术相互形塑,不仅技术调节着教师的经验和行动,而且教师也在“处置”、重构乃至重塑技术。“共塑”论不仅拒斥“替代论”、消除“恐惧论”,而且超越“代具论”和“互补论”,其实践意蕴在于让我们重新认识技术使用中教师的地位,明晰教师的技术使用责任,突破对技术的功能性认识,倡导技术“使用的技艺”,在技术设计中融入教师的教育价值诉求,真正让教师使用好技术。

关键词：技术调节 “师一技”关系 “共塑”

RH-ENDOSTATIN PLUS GEMCITABINE/NAVELBINE AND CISPLATIN AS FIRST-LINE TREATMENT PROTOCOL FOR NON-SMALL CELL LUNG CANCER PATIENTS:A SINGLE CENTRE STUDY

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Medical Bulletin of Shanghai Jiaotong University 2011年第1期23卷 32-37页

作者：周剑平项轶万欢英高蓓莉 Department of Respiratory Medicine Ruijin HospitalShanghai Jiaotong University School of Medicine

Objective To assess the efficacy of Rh-endostatin plus the combination of gemcitabine/navelbine and cisplatin in patients with non-small cell lung cancer (NSCLC).Methods NSCLC patients,not receiving chemotherapy,were divided into two *** they were given the combination of gemcitabine/navelbine and cisplatin with or without Rh-endostatin at 2-week intervals for 4 treatment *** Forty patients were enrolled and all of them were assessable for response and *** had complete response but 4 patients had partial *** overall response rate was 10%.The survival rate was 65% at 1 year,with a median survival time of 16.2 *** complications were the most common toxic reactions,with grade≥3 reactions occurring at rates of 7%,7%,4% and 2%,*** Rh-endostatin may have anti-tumor activity with high clinical benefit rate and is well tolerated in lung cancer with stage Ⅲb/Ⅳ.Compared with single combination of gemcitabine/navelbine and cisplatin,no more significant unexpected adverse events were observed.

关键词： non-small cell lung cancer Rh-endostatin efficacy toxicity

On the Initial Layer and the Limit Behavior for Chemotaxis System with the Effect of Fluid in Fourier Space

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 1015-1024页

作者： jian-xiang WAN Hai-ping ZHONG Department of Mathematics Jiangxi University of Finance and EconomicsNanchang 330032China School of Mathematics and Computer Yuzhang Normal UniversityNanchang 330103China

The paper deals with a Cauchy problem for the chemotaxis system with the effect of fluid■where d≥*** is known that for each∈>0 and all sufficiently small initial data(u_(0),n_(0),c_(0))belongs to certain Fourier space,the problem possesses a unique global solution(u^(∈),n^(∈),c^(∈))in Fourier *** present work asserts that these solutions stabilize to(u^(∞),n^(∞),c^(∞))as∈^(-1)→***,we show that c^(∈)(t)has the initial layer as∈^(-1)→*** one expects its limit behavior maybe give a new viewlook to understand the system.

关键词： chemotaxis system initial layer limit behavior Fourier space

Chaotic Ratchet Effect for Bose-Einstein Condensed Atoms in 1D Optical Lattices

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Communications in Theoretical Physics 2008年第12期50卷 1355-1360页

作者： FANG jian-Shu ZHANG xiang-ping Institute of physics Hunan University of Technology Zhuzhou 412008 China Department of Physics Hunan Normal University Changsha 410081 China

The chaotic ratchet effect for Bos-Einstein condensed atoms in an optical lattice is investigated. By using the direct perturbation method we obtain the chaotic solution of the condensed system. Theoretical analysis reveals that the transport of the condensed atoms in the ratchet potential is a chaotic one, and corresponding numerical results agree well with the theoretical results.

关键词： chaotic ratchet effect condensed atoms optical lattices

Isolation and identification of bacteria responsible for simultaneous anaerobic ammonium and sulfate removal

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Science China Chemistry 2010年第3期53卷 644-649页

作者： Cai, Jing jiang, jian xiang Zheng, ping Department of Environmental Engineering Zhejiang University Hangzhou 310029 China

Sulfate-dependent anaerobic ammonium oxidation is a novel biological reaction,in which ammonium is oxidized with sulfate as the electron acceptor under anoxic *** and sulfate are cosmopolitan chemical species which are an integral part of the global nitrogen and sulfur cycles.A detailed exploration of sulfate-dependent anaerobic ammonium oxidation is quite *** this work,a bacterial strain named ASR has been isolated from an anaerobic ammonia and sulfate removing reactor working under *** the basis of electron microscopy,physiological tests and 16S rDNA phylogenetic sequence analysis,the strain ASR is found to be related to Bacillus *** to the biological carbon source utilization test,the strain ASR could use many carbon *** optimum pH value and temperature were 8.5 and 30 °C,*** test proves that the strain ASR is able to use sulfate to oxidize ammonia *** maximum ammonia and sulfate removal rates were 44.4% and 40.0%,*** present study provided biological evidence for the confirmation and development of sulfate-dependent anaerobic ammonium oxidation and brought new insights into the global nitrogen and sulfur cycles.

关键词： bacillus ammonia sulfate isolation and identification

Bifurcations and Chaos in Duffng Equation with Damping and External Excitations

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 483-504页

作者： Mei-xiang CAI jian-ping YANG Jin DENG Institute of Mathematics and Physics Central South University of Forestry and Technology College of Science China Agriculture University Department of Mathematics and Physics Hunan Institute of Engineering

Duffing equation with damping and external excitations is investigated. By using Melnikov method and bifurcation theory, the criterions of existence of chaos under periodic perturbations are obtained. By using second-order averaging method, the criterions of existence of chaos in averaged system under quasi-periodic perturbations for Ω = nω ＋ εσ, n = 2,4,6 （where σ is not rational to ω） are investigated. However, the criterions of existence of chaos for n = 1, 3, 5, 7 - 20 can not be given. The numerical simulations verify the theoretical analysis, show the occurrence of chaos in the averaged system and original system under quasi- periodic perturbation for n = 1, 2, 3, 5, and expose some new complex dynamical behaviors which can not be given by theoretical analysis. In particular, the dynamical behaviors under quasi-periodic perturbations are different from that under periodic perturbations, and the period-doubling bifurcations to chaos has not been found under quasi-periodic perturbations.

关键词： Duffing equation Melnikov method second-order averaging method chaos

Bifurcations of Resonant Solutions and Chaos in Physical Pendulum Equation with Suspension Axis Vibrations

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Acta Mathematicae Applicatae Sinica 2010年第4期26卷 677-704页

作者： xiang-ling Fu Jin Deng jian-ping Yang School of Mathematics Hunan University of Science and TechnologyHunan 411201China College of Mathematics and Computer Sciences Hunan Normal UniversityHunan 410081China Department of Mathematics and Physics Hunan Institute of EngineeringHunan 411104China College of Science China Agricultural UniversityBeijing 100083China

This paper is a continuation of ＂Complex Dynamics in Physical Pendulum Equation with Suspension Axis Vibrations＂[1].In this paper,we investigate the existence and the bifurcations of resonant solution for ω0：ω：Ω ≈ 1：1：n,1：2：n,1：3：n,2：1：n and 3：1：n by using second-order averaging method,give a criterion for the existence of resonant solution for ω0：ω：Ω ≈ 1：m：n by using Melnikov＇s method and verify the theoretical analysis by numerical *** numerical simulation,we expose some other interesting dynamical behaviors including the entire invariant torus region,the cascade of invariant torus behaviors,the entire chaos region without periodic windows,chaotic region with complex periodic windows,the entire period-one orbits region;the jumping behaviors including invariant torus behaviors converting to period-one orbits,from chaos to invariant torus behaviors or from invariant torus behaviors to chaos,from period-one to chaos,from invariant torus behaviors to another invariant torus behaviors;the interior crisis;and the different nice invariant torus attractors and chaotic *** numerical results show the difference of dynamical behaviors for the physical pendulum equation with suspension axis vibrations between the cases under the three frequencies resonant condition and under the periodic/quasi-periodic *** exhibits many invariant torus behaviors under the resonant *** find a lot of chaotic behaviors which are different from those under the periodic/quasi-periodic ***,we did not find the cascades of period-doubling bifurcation.

关键词： Pendulum equation suspension axis vibrations averaging method Melnikov's method bifurcations chaos three frequencies resonances resonant solution