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The suspended sediment transport equation and its near-bed sediment flux

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Science china(Technological Sciences) 2009年第2期52卷 387-391页

作者： LI RuiJie1,2, LUO Feng2 & ZHU WenJin3 1 Key laboratory of Coastal Disaster and Defence (Hohai university), Ministry of Education, nanjing 210098, china 2 laboratory of Marine Environment, Hohai university, nanjing 210098, china 3 Institute of Physical Oceanography, Hohai university, nanjing 210098, china 1. Key laboratory of Coastal Disaster and Defence (Hohai university) Ministry of Education Nanjing 210098 China 2. laboratory of Marine Environment Hohai University Nanjing 210098 China 3. Institute of Physical Oceanography Hohai University Nanjing 210098 China

The suspended sediment transport equation and its near-bed sediment flux are one of the key problems of sediment transport research under nonequilibrium condition. Based on the three-dimensional primitive suspended transport equation, the two-dimensional suspended sediment transport equation is deduced. The derived process indicates that the physical essence of the near-bed sediment flux is right the bottom boundary condition for the suspended sediment transport equation. This paper analyzes the internal relations between the two methods of sediment carrying capacity and shear stress in common use, points out the consistency of these two methods in terms of form and physical meaning, and unifies these two methods theoretically. Furthermore, based on the analysis and comparison of the expressions of the near-bed sediment flux, this paper summarizes some problems to which attention should be paid, thus offering a novel approach to the study and the solution of the problems of suspended sediment transport and exchange flux of near-bed water sediment.

关键词： suspended sediment transport equation near-bed sediment flux sediment carrying capacity shear stress

泛在网络中的等效频谱带宽概念及其在异构网络切换中的应用

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通信学报 2012年第3期33卷 130-136页

作者：潘甦叶强刘胜美南京邮电大学无线通信江苏省重点实验室江苏南京210003 东南大学移动通信国家重点实验室江苏南京210096

未来无线通信系统将融合多种异构无线接入网络以提供泛在业务。为了表达用户在不同系统中占用的资源,为异构无线网络提出了等效带宽的概念,在此基础上将等效带宽用到异构网络切换控制中,同时将马尔科夫决策过程引入切换算法。仿真结果... 详细信息

未来无线通信系统将融合多种异构无线接入网络以提供泛在业务。为了表达用户在不同系统中占用的资源,为异构无线网络提出了等效带宽的概念,在此基础上将等效带宽用到异构网络切换控制中,同时将马尔科夫决策过程引入切换算法。仿真结果表明本算法相对于门限切换法有较好的期望收益。

关键词：泛在网络等效频谱带宽资源管理垂直切换

INTERLEAVING SCHEME FOR MULTICARRIER CDMA SYSTEM

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Journal of Electronics(china) 2004年第1期21卷 16-22页

作者： ShiFeng ChengShixin nationalmobilecommunicationsresearchlaboratory SoutheastUniversityNanjing210096

In MultiCarrier Code-Division Multiple-Access (MC-CDMA) system, the received signals scattered in the frequency domain are combined to get frequency diversity gain. However, the frequency diversity gain is limited because of correlation between aubcarriers. A novel interleaving scheme for MC-CDMA system is proposed in this paper. A circular shifting register is introduced into each subcarrier branch to decrease the correlation between subcarriers. By using interleaving, frequency diversity gain of system is increased. System structure and model with interleaver are discussed. In the case of multiple users, Parallel Interference Cancellation (PIC) technique is also introduced. Computer simulations demonstrate the performance of proposed scheme, and the performance comparison of MC-CDMA with interleaver and conventional MC-CDMA system is shown as well.

关键词： Multicarrier Interleaving PIC

Potash-rich volcanic rocks and lamprophyres in western Shandong Province:^(40)Ar-^(39)Ar dating and source tracing

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Chinese Science Bulletin 2002年第2期47卷 91-99页

作者： QIU Jiansheng, XU Xisheng & LO Ching-HuaState Key laboratory of Mineral Deposit research of nanjing university, nanjing 210093, china Department of Earth Sciences, nanjing university, nanjing 210093, china Department of Geology, Taiwan Unive State Key laboratory of Mineral Deposit research of nanjing university Nanjing China Department of Earth Sciences Nanjing University Nanjing China Department of Geology Taiwan University Taibei China

Highly precise 40Ar-39Ar dating results demon-strate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-124.3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.711418) and distinctly negative εNd values ( -11.47--17.54), and are enriched in radiogenic lead (206Pb/204Pb=17.341-17.622, 207Pb/204Pb=15.525-15.538, 208Pb/204Pb=37.563-37.684). Similarly, the lamprophyres also have quite low εNd values (-11.57 - -19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings, and extensive comparisons of the Sr, Nd isotopic composi-tions with that of the related simultaneous rocks, it is con-cluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting

关键词： potash-rich volcanic rocks lamprophyres 40Ar-39Ar dating Sr-Nd-Pb isotope tracing western Shandong Province.

Two bimetallic W(Ⅳ)-Mn(Ⅱ) complexes based on octacyanometallates:structures and magnetic properties

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Science china Chemistry 2009年第11期52卷 1801-1807页

作者： LIU BaoLin,XIAO HongPing,SONG You & YOU XiaoZeng State Key laboratory of Coordination Chemistry,nanjing national laboratory of Microstructures,School of Chemistry and Chemical Engineering,nanjing university,nanjing 210093,china State Key laboratory of Coordination Chemistry Nanjing National Laboratory of Microstructures School of Chemistry and Chemical Engineering Nanjing University Nanjing China

Two cyano-bridged heterobimetallic coordination polymers,[{Mn(dpa)2}2W(CN)8·CH3CN·4H2O]n(1)(dpa = 2,2'-dipyridylamine) and [Mn2(H2O)4{W(CN)8}·3H2O]n(2),have been synthesized and characterized structurally and magnetically.X-ray analysis shows that complex 1 is a one-dimensional(1-D) polymer of W2(CN)4Mn2 square units in which adjacent square fragments are interlinked by sharing [W(CN)8]4-moieties to form an infinite *** 2 is a three-dimensional(3-D) polymer,which shows an unforeseen structure,exhibiting a 3-D open network with a 1-D channel(ca.13.21  × 11.82 ).Fitting of the magnetic properties indicates that both polymers exhibit weakly antiferromagnetic interactions between the adjacent Mn ions.

关键词： cyano-bridged coordination polymer magnetic property manganese(Ⅱ) complex

Structural properties of GaN(0001) epitaxial layers revealed by high resolution X-ray diffraction

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 68-71页

作者： XIE ZiLi 1,2,3, ZHOU YuanJun 1 , SONG LiHong 1,2 , LIU Bin 1 , HUA XueMei 1,2 , Xiu XiangQian 1 , ZHANG Rong 1,2,3 & ZHENG YouDou 1,2,3 1 JiangSu Provincial Key laboratory of Advanced Photonic and Electronic Materials and Department of Physics, nanjing university, nanjing 210093, china 2 nanjing national laboratory of Microstructures, nanjing 210093, china 3 NJU-Yangzhou Institute of Opto-electronics, Yangzhou, 225001, china 1. JiangSu Provincial Key laboratory of Advanced Photonic and Electronic Materials and Department of Physics Nanjing University Nanjing 210093 China2. Nanjing National Laboratory of Microstructures Nanjing 210093 China3. NJU-Yangzhou Institute of Opto-electronics Yangzhou 225001 China

High-resolution X-ray diffraction has been used to analyze GaN(0001) epitaxial layers on sapphire substrates. Several structural properties of GaN, including the lattice constants, strains, and dislocation densities are revealed by the technique of X-ray dffraction (XRD). Lattice constants calculated from the omega/2theta scan are c=0.5185 nm and a=0.3157 nm. Also, the in-plane strain is -1.003%, while out of the plane, the epitaxial film is almost relaxed. Several methods are used to deduce the mosaicity and dislocation density of GaN, showing that the edge type dislocations are the overwhelming majority.

关键词： GaN XRD dislocation epitaxial

Classification of Wavelet Bases by Translation Subgroups and Nonharmonic Wavelet Bases

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Acta Mathematica Sinica,English Series 2000年第2期16卷 307-312页

作者： Qiao Wang Department of Radio Engineering,southeast university,nanjing 2.0096,P.R.china Department of Radio Engineerin Southeast University Nanjing 210096 P. R. China

The structure of the set S of shiftable points of wavelet subspaces is researched in this *** prove that S=R or S=(1/q)Z where q ∈ *** spectral and functional characterizations for the shiftability are ***,the nonhar... 详细信息

关键词： Wavelet Translation invariance Functional characterization

Establishing time-dependent model of deformation modulus caused by bedrock excavation rebound by inverse analysis method

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Science china(Technological Sciences) 2008年第S2期51卷 1-7页

作者： WU ZhongRu1,2,GU YanChang1,3,GU ChongShi1,2,GUO HaiQing1 & SU HuaiZhi1,2 1 Hohai university,nanjing 210098,china 2 national Engineering research Center of Water Resources Efficient Utilization and Engineering Safety,nanjing 210098,china 3 nanjing Hydraulic research Institute,nanjing 210029,china 1. Hohai university Nanjing 210098 China 2. national Engineering research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China 3. nanjing Hydraulic research Institute Nanjing 210029 China

Rock rebound relaxation deformation,or even rock burst,caused by the excavation of dam base and abutment or high rock slope affects their stability and results in the fall of mechanical properties of the *** an inverse analysis method was proposed in this paper to establish the time-dependent model of deformation modulus caused by excavation *** basic principle is based on the combination of observed data of the excavation rebound deformation of dam abutment or rock slope,and the calculated rebound deformation by FEM under ground stress at the corresponding time in the excavation *** norm of the residuals of observed data and calculated data are taken as the objective ***,the time-dependent model of bedrock deformation modulus can be *** method displays its significance in the design of excavation,construction and operation management of dam base and high slope.

关键词： dam base rebound deformation modulus inverse analysis method time-dependent model Xiaowan Hydropower Station

PERFORMANCE OF MULTIUSER DETECTION FOR CDMA SYSTEM IN A FLAT RAYLEIGH FADING ENVIRONMENT

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Journal of Electronics(china) 1997年第3期14卷 285-288页

作者： Nie Jingnan Cheng Shixin You Xiaohu(national mobile communications research Lab, southeast university, nanjing 2.0096)

In a CDMA communication network using conventional signal detection, system capacity is limited and its performance is degraded by the multi-access interference (MAI). Multiuser detection, which makes use of cross-correlation information between spread spectrum codes, can reduce or eliminate the MAI in a Gaussian channel so as to mitigate the near-far effects and increase the system capacity. This paper extends the multiuser detector to a flat Rayleigh fading CDMA environment, and discusses the bit error rate of typical multiuser detection algorithms in such a environment by combining theoretical analysis and computer simulation. It is shown that multiuser detection is superior to conventional detections in the flat Rayleigh fading channels.

关键词： CDMA Rayleigh fading Multiuser detection