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The frequencies of high frequency quasi-periodic oscillations in two different frames in black hole LMXBs

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Research in Astronomy and Astrophysics 2011年第11期11卷 1327-1335页

作者： Chang-Sheng Shi college of Material Science and chemical Engineering,Hainan University,Hainan 5702.8,{2. Key Laboratory of Modern Astronomy and Astrophysics,nanjing University,nanjing 2.0093,{2. college of Material Science and chemical Engineering Hainan University Hainan 570228 China Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Nanjing 210093 China

We discuss the modes of the Alfvén waves in the accretion disk with a toroidal magnetic field in black hole low mass X-ray binaries in a rotating frame. By solving the perturbed general relativistic magnetohydrodynamic equations in the rotating frame, we find two stable modes of the Alfvén wave which are the same as those in the fiducial observer frame. This gives a feasible way to transform between the two different frames, which validates the possible Alfvén wave modes in the accreting celestial bodies with a toroidal magnetic field.

关键词： accretion accretion disks-magnetohydrodynamics-relativity

A new parameterization scheme for sea surface aerodynamic roughness

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Progress in Natural Science:Materials International 2008年第11期18卷 1365-1373页

作者： Yuping Pan~(a,b) Wenyu Sha~c Shouxian Zhu~c Sufang Ge~(a,*) a nanjing University of Information Science and technology,nanjing 2.0044,china b Air Force Meteorological Center of the nanjing Military Region,nanjing 2.0018,china c Meteorology college,The PLA University of Information Science and technology,nanjing 2.1101,china nanjing University of Information Science and technology Nanjing 210044 China Air Force Meteorological Center of the nanjing Military Region Nanjing 210018 China Meteorology college The PLA University of Information Science and Technology Nanjing 211101 China

The dimensionless roughness length derived from dimensional analysis bears a relation to wave age,and the dimensionless form of roughness length can be expressed with the relation with a significant wave *** on six experiments(HEXMAX,RASEX,BIO steady platform,Lake Ontario data analysis FETCH,CBLAST low wind),we verified that the Charnock parameter,Zch,and dimension- less roughness length,z0/Hs,are dependent on wave age,u*/***,we constructed a new scheme for roughness length,and explored its sensitivity to friction velocity and wave *** the newly developed parameterization scheme(PS07)with COARE (Coupled Ocean-Atmosphere Response Experiment V.3.0)algorithm,we calculated the data from the North Sea Platform experiment in December,1985,and made an attempt to validate the suitability of the PS07 compared to the other three schemes of *** found that the calculated results based on the PS07 are close to the *** also conducted an experiment in which the PS07 was combined with the nested model of waves coupling in datasets of 3 typhoons that occurred at the Zhanjiang *** comparison results between the calculated and observed waves around the Naozhou Island indicate that the new parameterization scheme(PS07)has a good applicability.

关键词： Sea surface roughness Parameterization scheme Significant wave height Wave age COARE algorithm

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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Science china(Information Sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2.& YANG LuXi 2.1 college of Communication and Information Engineering,nanjing University of Posts and Telecommunications,nanjing 2.0003,china 2.School of Information Science and Engineering,Southeast University,nanjing 2.0096,china college of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing China School of Information Science and Engineering Southeast University Nanjing China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Dynamic Mechanical Behaviour of Ultra-high Performance Fiber Reinforced Concretes

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Journal of Wuhan University of technology(Materials Science) 2008年第6期23卷 938-945页

作者：赖建中 Department of Materials Science & Engineering Nanjing University of Science & Technology

Ultra-high performance fiber reinforced concretes （UHPFRC） were prepared by replacing 60% of cement with ultra-fine industrial waste powder. The dynamic mechanical behaviour of UHPFRC with different fiber volume fraction was researched on repeated compressive impact in four kinds of impact modes through split Hopkinson pressure bar （SHPB）. The experimental results show that the peak stress and elastic modulus decrease and the strain rate and peak strain increase gradually with the increasing of impact times. The initial material damage increases and the peak stress of the specimen decreases from the second impact with the increasing of the initial incident wave. Standard strength on repeated impact is defined to compare the ability of resistance against repeated impact among different materials. The rate of reduction of standard strength is decreased by fiber reinforcement under repeated impact. The material damage is reduced and the ability of repeated impact resistance of UHPFRC is improved with the increasing of fiber volume fraction.

关键词： ultra-high performance fiber reinforced concretes split Hopkinson pressurebar dynamic repeated impact

Web Application Comprehension Based on Dependence Analysis

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2., XU Bao-wen 1 , JIANG Ji-xiang 1 1.Department of Computer Science and Engineering, Southeast University, nanjing 2.0096, Jiangsu, china 2.{2. of Computer Science and Engineering, nanjing University of technology, nanjing 2.0009, Jiangsu , china Department of Computer Science and Engineering Southeast University Nanjing Jiangsu China college of Computer Science and Engineering Najing University of Technology Nanjing Jiangsu China

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 311 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (60373066, 6030302.). National Grand Fundamental Research 973 Program of china (2.02.B312.00) and National Research Foundation for the Doctoral Program of Higher Education of chinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing

Structure splitting framework for data-layout optimization

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The Journal of china Universities of Posts and Telecommunications 2009年第5期16卷 107-113页

作者： FU Xiong , WANG Ru-chuan college of Computer, nanjing University of Posts and Telecommunications, nanjing 2.0003, china college of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

To improve data cache performance, optimizing program data layout by data reorganization has become an important method of decreasing the impact of increasing gap of speed between processor and memory. In this article, a structure splitting framework with an analysis model named structure field relation graph （SFRG） is presented to optimize program data layout. The SFRG can be used to quantify relationship between fields. It helps to find an optimal layout for structure as well as the optimal program data layout. And the data cache performance is improved through SFRG-based structure splitting. Experiments show that this framework is effective in optimizing program data layout and improving the performance of data cache and whole program.

关键词： program optimization structure splitting data layout cache performance

Controlled free radical polymerization of styrene initiated from the alkoxyamine-functionalized silicon surface

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Science china Chemistry 2005年第5期48卷 449-458页

作者： CHEN Zhijun1, ZHOU Sikai1, LU Wenzhong1, FANG Shaoming1, JIANG Xiqun2.& YANG Changzheng2.1. college of Materials and chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002. {2. 2. Laboratory of Mesoscopic Material Science and Department of Polymer Science & Engineering, college of Chemistry & chemical Engineering, nanjing University, nanjing 2.0093, {2. college of Materials and chemical Engineering Zhengzhou University of Light Industry Zhengzhou China Laboratory of Mesoscopic Material Science and Department of Polymer Science & Engineering College of Chemistry & Chemical Engineering Nanjing University Nanjing China

We describe a new method of fabricating a brush-like polystyrene layer anchored on the surface of the silicon substrate, which involves three steps, namely (i) the attachment of 3-methacryloxypropyltrimethoxysilane onto the silicon surface; (ii) the reaction of vinyl moiety at another extremity of the anchored 3-methacryloxypropyltrimethoxysilane to 4-Hydroxyl-2. 2. 6, 6-tetramethyl-1-piperidinyloxy (HTEMPO?) catalyzed by azobisisobutyronitrile (AIBN); (iii) living free radical grafting polymerization of styrene in the presence of HTEMPO?. The controllable living free radical polymerization permits accurate control of both the molecular weight and the polydispersity. X-photoelectron spectroscopy measurement proved that the alkoxyamine initiator layer forms on the silicon surface. XPS and Ellipsometry measurements showed that the poly-styrene chains were covalently anchored onto the silicon surface. The thickness of the grafted polymer layer can be accurately manipulated by altering the polymerization time. The new method allows synthesizing random copolymer and block copolymers by the sequential growth of monomers from the substrate surface.

关键词： polymer brush, controlled living free radical polymerization, thickness, atomic force microscopy, 3-methacryloxypropyltrimethoxysilane.

Tsallis model-based separation of overlapped peak signals

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Science china(Information Sciences) 2010年第4期53卷 823-832页

作者： LI YuanLu*, ZHANG YingChao & TANG HuiQiang college of Information and Control, nanjing University of Information Science & {2., nanjing 2.0044, china college of Information and Control Nanjing University of Information Science & Technology Nanjing China

A simple scheme for separating overlapped peak signals (OPS) is proposed, with the Tsallis distribution as the model for OPS processing and fractional-order differentiation as tool for the signal analysis, the relationships of the maxima and zero-crossing values of the Tsallis peak signal, separately, to the order of differentiation are established, leading to two types of parameter estimators, which are utilized, by adjusting the peak-shape parameter, to calculate the parameters of position, height and width of the Gaussian, Lorentzian and Tsallis distribution. The obtained characteristic parameters can be employed to fit the peak signals to be treated, thereby fulfilling the OPS decomposition.

关键词： fractional differentials filter overlapped peak signal Tsallis model separation of overlapped peak signals

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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Science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2. BI GuangGuo3 & XU WeiYe4 1 college of Information Science and technology, {2. University of Aeronautics and Astronautics, {2. 2.0016, china 2.Department of Electronic Engineering, City University of Hong Kong, Hong Kong, china 3 National Mobile Communications Research Laboratory, Southeast University, {2. 2.0096, china 4 Department of Communication Engineering, {2. Institute of technology, {2. 2.1167, china college of Information Science and technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Electronic Engineering City University of Hong Kong Hong Kong China National Mobile Communications Research Laboratory Southeast University Nanjing China Department of Communication Engineering Nanjing Institute of Technology Nanjing China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation