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Finite Element Harmonic Solution of the Coupled Rotor-bearing System

厦门大学学报（自然科学版） 2002年第S1期41卷 180-181页

作者： CAI Ting, YANG Jian-gang (national Engineering research Center of Turbogenerator Vibration, So utheast university, nanjing 210096, china)

Fluid-solid interaction problems have been studied q uite extensively in the past years. Rotor-bearing system is a typical example. Fluid field is changed under the exciting of rotor vibration. On the same ti me, a net force caused by fluid pressure exerts on rotor, which will change roto r vibration. So, the fluid-solid coupled analysis method must be used. Traditionally, numerical difference method was used to solve fluid problems. The coupled fluid-solid equation could not be set up based on the method. It is no t until finite element method was used in fluid dynamics area then can the coupl ed dynamics be researched. Recently many experimental, analytical and numerical studies have been used in the area . But in these investigations, it is a ssumed that the solid vibration could not be influenced by fluid. In the other w ords, the force exerted on solid from fluid was neglected in the papers. So, the models built were some kinds of semi-coupled model only. In this paper, the Galerkin finite-element method, two-dimension vibration equ ation of rigid body and Navier-Stokes equations are used to build a full-coupl ed fluid-solid model in rotor-bearing system. Some assumptions are taken: 1) In fluid equation, the nonlinear terms are relatively small and neglected. 2) The gravity takes no effect on this system. 3) The bearing and the rotor are long. Flow and leakage along the axis is neglec ted. 4) The fluid is a kind of Newtonian incondensable viscous fluid. 5) The rotor is considered to be a rigid body. Using the model established, we calculated all the examples given by paper , results show the error are less than 7%. So the full-coupled model is built c orrectly. Examples are given in the end of the paper. After analyzing the examples, we get some conclusions: 1) In rotor-bearing system, while being taken under two conditions that whether coupled method is taken or not, difference of pressure and vibration amplitude could reach 76% and 120%. Therefore coupled met

关键词： Finite Element Harmonic Solution of the Coupled Rotor-bearing System

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Hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding

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Science china(Technological Sciences) 2011年第4期54卷 793-798页

作者： BAO TengFei1,2,3,XU BaoSong1,2,3 & ZHENG XueQing1,2,3 1State Key laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai university,nanjing 210098,china 2national Engineering research Center of Water Resources Efficient Utilization and Engineering Safety,nanjing 210098,china 3College of Water Conservancy and Hydropower Engineering,Hohai university,nanjing 210098,china State Key laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing China national Engineering research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing China

A hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding is *** finite element internal force method(FEIFM) is used to provide more accurate thrust forces acting on the faces of a slip body,and the limit equilibrium method(LEM) is employed to evaluate the factor of safety of the slip *** method presented can deal with a slip body with large amount of geometrically complex slip *** addition,compared with the traditional LEM,it can meet the balance condition of the forces in the slip *** example shows that the factor of safety obtained by the method presented agrees well with the theoretical solution.A practical example is also presented to demonstrate the application of the method in the stability analysis of an arch dam *** results from the examples show that the method is promising in analysis of arch dam stability against sliding.

关键词： arch dam stability against sliding limit equilibrium method finite element internal force method

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Performance analysis of a noise-normalized FFH/MFSK receiver over Rayleigh fading channels with partial-band noise jamming

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Science china(Information Sciences) 2011年第1期54卷 129-135页

作者： ZHOU ZhiQiang,LI ShaoQian & CHENG YuFan national Key laboratory of Science and Technology on communications,university of Electronic Science and Technology of china,Chengdu 610054,china national Key laboratory of Science and Technology on communications University of Electronic Science and Technology of China Chengdu China

Fast frequency hopping can reduce the degradation caused by *** performance of noise-normalized fast frequency-hopped M-ary orthogonal frequency-shift-keying(FFH/MFSK)receivers over frequency nonselective Rayleigh fading channels with partial-band noise jamming is *** of numerical evaluation,a closed-form error probability expression is given based on the theory of complex variables. The simulation results validate the analytical *** is shown that there is an optimum diversity order and the system performance gets better with an increase in the modulation order.

关键词： anti-jamming fast frequency hopping noise normalization combining Rayleigh fading

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A Case Study of 3D Protein Structure Prediction with Genetic Algorithm and Tabu Search

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Wuhan university Journal of Natural Sciences 2011年第2期16卷 125-129页

作者： WANG Ting1,2, ZHANG Xiaolong1, 3 1. School of Computer Science and Technology, Wuhan university of Science and Technology, Wuhan 430065, Hubei, china 2. College of mobile Telecommunications, Chongqing university of Posts and Telecommunications, Chongqing 400065, china 3. State Key laboratory of Bioelectronics, southeast university, nanjing 210096, china School of Computer Science and Technology Wuhan University of Science and Technology Wuhan Hubei China College of mobile Telecommunications Chongqing University of Posts and Telecommunications Chongqing China State Key laboratory of Bioelectronics Southeast University Nanjing China

This paper describes a case study of 3D protein structure prediction of six sequences from protein data bank （PDB） by genetic algorithm and tabu search （GATS）, where off-lattice AB model is considered as a simplified model of protein structure. The lowest-energy values required for forming the native conformation of proteins are searched by GATS, and then the coarse structures （i.e., simplified structure） of the proteins are obtained according to the multiple angle parameters corresponding to the lowest energies. All the coarse structures form single hydrophobic cores surrounded by hydrophilic residues, which stay on the right side of the actual characteristic of protein structure. It demonstrates that this approach can predict the 3D protein structure effectively.

关键词： 3D protein structure off-lattice AB model genetic algorithm and tabu search (GATS)

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research and Simulation on Non-Blind Adaptive Beamforming Algorithm for TD-SCDMA System

Research and Simulation on Non-Blind Adaptive Beamforming Al...

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中国通信学会第六届学术年会

作者： Mengjuan Yu~1,Lianfeng Shen~1,Bo Xu~2 (1 national mobile communications research laboratory,southeast university,nanjing 210096,china 2 Institute of communications Engineering,PLA university of Science and Technology,nanjing 210018,china)

Adaptive beamforming algorithms continue to be a research hotspot of smart *** adaptive beamforming algorithms, non-blind adaptive algorithms attract most researchers'''' interests because they have better feasibility,stability performance and they are not affected by the accuracy of DOA *** performance of non-blind adaptive algorithms used in TD-SCDMA communication system has not been studied and simulated in-depth *** paper tries to simulate and compare three typical nonblind adaptive algorithms including Least Mean Square algorithm(LMS),Recursive Least Squares algorithm(RLS),the Sample Covariance Matrix Inversion algorithm(SMI) for TD-SCDMA *** simulation results show that all three algorithms can mitigate interferences,save power and improve the quality of *** simulation also indicates that better performances and applicability are obtained when the weights are estimated using the RLS algorithm than the LMS and SMI algorithms.

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Syntheses,crystal structures and properties of three novel coordination polymers with tripodal imidazole-containing ligands and benzenetetracarboxylate

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Science china Chemistry 2010年第10期53卷 2164-2169页

作者： SU Zhi, FAN Jian & SUN WeiYin State Key laboratory of Coordination Chemistry nanjing national laboratory of Microstructures Coordination Chemistry Institute, School of Chemistry and Chemical Engineering, nanjing university, nanjing 210093, china State Key laboratory of Coordination Chemistry nanjing national laboratory of Microstructures Coordination Chemistry Institute School of Chemistry and Chemical Engineering Nanjing University Nanjing China

Three novel coordination polymers, [Ni2(tib)2(btec)]·2H2O (1), [Co2(tib)2(btec)]·2H2O (2) and [Zn4(tib)2(btec)Cl4]·2H2O (3), have been synthesized by using mixed ligands of 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,2,4,5-benzenetetracarboxylic acid (H4btec) under hydrothermal conditions. Complexes 1 and 2 have the same structure and are rare three-dimensional (3D) self-penetrating (3,4,5)-connected nets, while complex 3 is an unprecedented (3,4)-connected 3D net. The different structures of 1 (2) and 3 are ascribed to the distinct coordination geometry of the metal centers. The thermal stability and photoluminescence property of the complexes were investigated.

关键词： coordination polymer self-penetration crystal structure thermal stability photoluminescence property

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Local and global behavior for algorithms of solving equations

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Chinese Science Bulletin 2001年第6期46卷 441-448,529页

作者： WANG Xinghua & LI ChongDepartment of Mathematics, Zhejiang university, Hangzhou 310028, china Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, china Department of Applied Mathematics, southeast university, nanjing 210096, china Department of Mathematics Zhejiang University Hangzhou China Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China Department of Applied Mathematics Southeast University Nanjing China

The theory of 'point estimate' and the concept of 'general convergence', which were put forward by Smale in order to investigate the complexity of algorithms for solving equations, have been producing a deep impact on the research about the local behavior, the semi-local behavior and the global behavior of iteration methods. The criterion of point estimate introduced by him not only provides a tool for quantitative analysis of the local behavior but also motivates the establishing of the unified determination for the semi-local behavior. Studying the global behavior in the view of discrete dynamical system will lead to many profound research subjects and open up a rich and colorful prospect. In this review, we will make a summarization about the research progress and some applications in nonsmooth optimizations.

关键词： Banach space nonlinear operator equation point esti-mate Sullivan domain nonsmooth optimization.

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SUC检测下的新型VBLAST调制方案性能分析与研究

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通信学报 2009年第2期30卷 47-51页

作者：蒋占军潘文王炎尤肖虎东南大学移动通信国家重点实验室

设计了一种应用于VBLAST系统的新型调制方案,来改善系统接收端作连续干扰抵消(SUC)检测时出现错误传播导致系统传输可靠性下降的问题。在该调制方案中对先检测的信号选用抗噪声性能高的调制方式(例如二进制相移键控调制),而对后续检测... 详细信息

设计了一种应用于VBLAST系统的新型调制方案,来改善系统接收端作连续干扰抵消(SUC)检测时出现错误传播导致系统传输可靠性下降的问题。在该调制方案中对先检测的信号选用抗噪声性能高的调制方式(例如二进制相移键控调制),而对后续检测的信号逐步选用频带利用率较高的调制方式(例如多进制调制),从而降低先检测的信号对后检测的信号的影响。分析与仿真结果表明,采用该方案的系统在不降低系统传输有效性的条件下,接收端作SUC检测时的传输可靠性有了一定程度的提高。

关键词： MIMO BLAST 连续干扰抵消调制

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Spatial distribution of 10m firn temperature in the Antarctic Ice Sheet

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Science china Earth Sciences 2011年第5期54卷 655-666页

作者： WANG YeTang1,3 & HOU ShuGui2,3 1 Shandong Marine Fisheries research Institute,Yantai 264006,china 2 MOE,Key laboratory for Coast and Island Development,School of Geographic and Oceanographic Sciences,nanjing university,nanjing 210093,china 3State Key laboratory of Cryospheric Science,Cold and Arid Regions Environmental and Engineering research Institute,Chinese Academy of Sciences,Lanzhou 730000,china Shandong Marine Fisheries research Institute Yantai China State Key laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China MOE Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing China

A database of Antarctic 10 m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital elevation model and the main ice divide were used to delineate main drainage sectors across Antarctica. In each drainage sector, a quantitative relationship between temperature and latitude, longitude and altitude was established using available tim temperature data. Quantitative relationships incorporating other factors affecting Antarctic air temperature such as atmospheric circulation and small-scale to- pography were used to derive a 10-km resolution grid map of surface temperature. The resulting temperature patterns presented a reasonable depiction of both large and small-scale variations in Antarctic 10 m firn temperature. This map is useful for many spatial variation studies, Antarctic ice sheet models, and comparison with satellite-derived temperature data and outputs of atmospheric general circulation models.

关键词： Antarctica 10 m firn temperature spatial distribution

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A NOVEL TRACKING ALGORITHM BASED ON GRAVITY OF ENERGY WINDOWS FOR DS/CDMA SYSTEM

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Journal of Electronics(china) 2000年第4期17卷 313-318页

作者： Guo Jinghong You Xiaohu Cheng Shixin (national mobile Communication research laboratory, southeast university, nanjing 210018)

PN (Pseudo-Noise) code tracking is the most challenging task in a Direct Sequence Spread Code Division Multiplex Access (DS-CDMA) for celluar mobile communication systems. In this paper, the gravity of energy windows (GEW) tracking loop of the time and frequency uncertainty of the received signal is investigated, and the GEW’s analytical results in a multi-path fading channel are introduced. GEW tracking loop exploits the inherent multi-path diversity of the channel, and has better performance than single-path one when working in multi-path fading environment.

关键词： PN tracking DS/CDMA Energy window

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