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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, nanjing university of Aeronautics and Astronautics, nanjing 2.0016, china 2.Department of Electronic Engineering, City university of Hong Kong, Hong Kong, china 3 national mobile communications research Laboratory, southeast university, nanjing 2.0096, china 4 Department of Communication Engineering, nanjing Institute of Technology, nanjing 2.1167, china College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Department of Electronic Engineering City University of Hong Kong Hong Kong China national mobile {2. research Laboratory Southeast University Nanjing 210096 China Department of Communication Engineering Nanjing Institute of Technology Nanjing 211167 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

SQUARE attack on block ciphers with low algebraic degree

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Science china(Information Sciences) 2010年第10期53卷 1988-1995页

作者： SUN Bing 1 , LI RuiLin 1 , QU LongJiang 1,3 & LI Chao 1,2.3 1 Science College of national university of Defense Technology, Changsha 410073, {2. 2.State Key Laboratory of Information Security, Graduate university of Chinese Academy of Sciences, Beijing 100049, {2. 3 national mobile communications research Laboratory, southeast university, nanjing 2.0096, {2. 1. Science College of national university of Defense Technology Changsha 410073 China3. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China

By using an algebraic method, the mathematical foundation of SQUARE attack is studied in this paper. We point out that a SQUARE distinguisher exists if and only if the degree of the polynomial function between n-bit input which is active and n-bit output which is balanced is 2.n-2. And the algebraic method can also be used to determine the property of a balanced set after passed through a nonlinear S-box, by which in some cases we can find a SQUARE distinguisher with more rounds. The validity of SQUARE attack and the influence of the choice of S-box are also studied. If the round function of a Feistel cipher has a low algebraic degree, a SQUARE attack cannot recover the right keys in some special cases. However, SQUARE attack on SPN ciphers always holds. The relations among SQUARE attack and some other cryptanalytic method are studied, showing that if a cipher is breakable by SQUARE attack, then it is also breakable by the interpolation attack.

关键词： SQUARE attack interpolation attack integral attack block cipher

Spectral Estimation based on Filter Bank and Cepstrum Thresholding for Cognitive Radios

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china communications 2009年第1期6卷 92-98页

作者： Cao Zhiping, Bi Guangguo, Zhang Zaichen national mobile Communication {2. Laboratory, School of Information Science and Engineering, southeast university, nanjing 2.0096, china national mobile Communication {2. Laboratory School of Information Science and Engineering Southeast University Nanjing 210096 China

Spectrum sensing plays an important role in cognitive radio (CR). Nonparametric spectrum estimation is considered as a feasible candidate for CR. Some filter bank based periodogram algorithms, such as Thomson’s multitaper spectral estimator, can achieve fine spectral dynamic range1 but have large estimation variance. On the other hand, recently, Cepstrum Thresholding is proposed to reduce the variance of periodogram estimation. In this paper, we combine these two methods to achieve spectral dynamic range and variance request at the same time.

关键词： spectrum analysisfifilter bank cepstrum thresholding.

Study on lithogeochemistry of Middle Jurassic basalts from southern china represented by the Fankeng basalts from Yongding of Fujian Province

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Science china Earth Sciences 2006年第10期49卷 1020-1031页

作者： ZHOU Jincheng1,2. JIANG Shaoyong1,2. WANG Xiaolei1,2. YANG Jinghong 1,2.& ZHANG Mengqun 3 1. State Key Laboratory of Mineral Deposit research, nanjing {2., nanjing 2.0093, china 2. Department of Earth Sciences, nanjing {2., nanjing 2.0093, china 3. Modern Analysis Center, nanjing {2., nanjing 2.0093, china 1. State Key Laboratory of Mineral Deposit research Nanjing University Nanjing 210093 China 2. Department of Earth Sciences Nanjing University Nanjing 210093 China 3. Modern Analysis Center Nanjing University Nanjing 210093 China

There exists an E-W trending Middle Jurassic volcanic zone in southern china. The Fankeng basalts in the Yongding basin of Fujian Province are considered to be a typical example. The Fankeng basalts have TiO2.contents in the range of 1.92.-3.2.%. They are classified as high-Ti basalts. They also have higher total Fe (averaging FeO* = 11.09%). The Middle Jurassic Fankeng basalts from southwestern Fujian have obvious distinctive lithogeochemical features from early Cre- taceous basalts from southeastern coast of china. They have higher HFSE, such as Th, Nb, Ta, Zr and Ti. Their element ratios related with HFSE, such as Zr/Ba, La/Nb, La/Ta ,Zr/Y, Ti/Y, Ba/Nb, K/Ti and Rb/Zr are similar to those of OIB. The most samples have ε Nd(T) of-0.70-0.2., which are near chondrite. Some samples have higher ε Nd(T) of ***, these basaltic magmas might be derived from depleted asthenospheric mantle. The lithogeochemical characteristics of the Fankeng basalts may be caused by interaction between asthenosphere and lithosphere at the time. The (Early-) Middle Jurassic basalts and gabbros from southeastern Hunan, southern Jiangxi and northern Guangdong provinces show similar geochemical features to those of the Fankeng basalts from the Yongding of Fujian. Occurrence of these OIB-type basalts in the area may be regarded as the petrological mark of upwelling of asthenosphere at the time. Upwelling of asthenosphere has led to tectonic extension and the formation of rifted basin in the area.

关键词： interaction between asthenosphere and lithosphere, lithogeochemistry, basalts, Middle Jurassic, southern china.

Study on impurity desorption induced by femtosecond pulse laser based on a stochastic process model

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Science china(Technological Sciences) 2006年第1期49卷 78-88页

作者： CHI Yinsheng1, LIN Xiaohui1, ZHUANG Ping1 & CHEN Yunfei1,2.1. Department of Mechanical Engineering, southeast university, nanjing 2.0096, {2. 2. Key Laboratory of MEMS of {2. Educational Ministry, southeast university, nanjing 2.0096, {2. Department of Mechanical Engineering Southeast University Nanjing 210096 China Key Laboratory of MEMS of china Educational Ministry Southeast University Nanjing 210096 China

With the advantages on non-equilibrium heating and desorption induced by electronic transition, the femtosecond pulse laser introduces a new way for solving the problem of impurity pollution adsorbed on a solid thin film in micro-electro-mechanical systems (MEMS). A model based on stochastic processes was established for stimulated desorption induced by the femtosecond pulse laser to interpret the interaction of the opti-cally excited hot electrons with the adsorbed molecules in a metal substrate. Numerical simulation results reveal a time-dependent desorption probability of adsorbed molecules and indicate that how key parameters of femtosecond pulse laser, such as incident laser energy flux, pulse duration, and wavelength of pulse, have a great effect on the desorption probability.

关键词： desorption, femtosecond pulse laser, stochastic process.

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 Tele{2.,nanjing 2.0003,china 2.School of Information Science and Engineering,southeast university,nanjing 2.0096,china 1. College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 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

The renascence of industrial historic buildings——Taking the protective remolding and reusing of Chenguang Mechanical Factory in nanjing as an example

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Science china(Technological Sciences) 2009年第9期52卷 2502-2509页

作者： WANG YanHui research Institute of Architecture,southeast university,{2.,china 1. research Institute of Architecture Southeast University Nanjing 210096 China

The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.

关键词： industrial historic buildings and sites protective remolding and reusing renascence strategy

Mechanical behavior of a shelter system based on cable-strut structures

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2012年第12期13卷 895-903页

作者： Jian-guo CAI1,2.Ya ZHOU1,Jian FENG1,2.Yi-xiang XU3 (1Key Laboratory of C&PC Structures of Ministry of Education,southeast university,nanjing 2.0096,{2.) (2.3} Prestress Engineering research Center,southeast university,nanjing 2.0096,{2.) (3Department of Civil Engineering,Strathclyde university,Glasgow,UK) 1. Key Laboratory of C&PC Structures of Ministry of Education Southeast University Nanjing 210096 China 2. national Prestress Engineering research Center Southeast University Nanjing 210096 China 3. Department of Civil Engineering Strathclyde University Glasgow UK

A shelter system based on cable-strut structures,consisting of compressive struts and high-tensile elements,is described in this *** deployment of the shelter is achieved by tightening inclined *** cables are used to terminate the *** state of self-stress of the cable-strut structures in the fully deployed configuration is given,and the minimum strut length and the maximum load design of the shelter are *** mechanical behavior of the system was studied under symmetrical and asymmetrical load *** results show that the shelter in the deployed configuration satisfies the ultimate limit and the serviceability limit state ***,the stability of the cable-strut system is investigated,considering the effect of imperfections on the buckling of the *** conclude that the influence of imperfections based on the consistent imperfection mode method is not significant.

关键词： Foldable structures Cable-strut structures Mechanical behavior Self-stress Stability

Restrictive mechanism of flow control among non-cooperative Internet users

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Science china(Information Sciences) 2011年第1期54卷 12-22页

作者： TAO Jun1,2.ZHONG Xiao1,2.& LU YiFei1,2.1Key Laboratory of Computer Network and Information Integration,southeast university, Ministry of Education,nanjing 2.0096,{2. 2.chool of Computer Science and Engineering,southeast university,nanjing 2.0096,{2. 1. Key Laboratory of Computer Network and Information Integration Southeast University Ministry of Education Nanjing 210096 China2. School of Computer Science and Engineering Southeast University Nanjing 210096 China

The flow and congestion control methods based on one-shot game model with non-cooperative game theory can explain the non-cooperative behavior of Internet ***,the low effciency of equilibrium solutions affects their *** the behavior of flow and congestion control based on infinitely repeated game models is addressed;the repeated and infinitely repeated flow and congestion control game model is presented; the existence and optimization of the Nash equilibrium point are proved;the discount factor in repeated game is discussed;the punishment and threat strategy to users'misbehavior is studied in N-users infinitely flow control game;the punishment restrictive method of users'behavior is designed in infinitely and finitely games;finally,a flow control algorithm based on repeated game,FCAR,is provided based on the conclusions of repeated game *** results of experiment and simulation show that FCAR algorithm could regularize and restrict users' misbehavior *** algorithm can also make non-cooperative Internet users achieve cooperation in order to optimize the utility of the whole flow and congestion control system.

关键词： Nash equilibrium utility infinitely and finitely repeated game flow and congestion control