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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 engineer.ng,nanjing university of Posts and Telecommunications,nanjing 210003,china 2 school of information science and engineer.ng,southeast university,nanjing 210096,china College of Communication and information engineer.ng Nanjing University of Posts and Telecommunications Nanjing China school of information science and engineer.ng 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

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 210096,china 2school of Computer science and engineer.ng,southeast university,nanjing 210096,china Key Laboratory of Computer Network and information Integration Southeast University Ministry of Education Nanjing China school of Computer science and engineer.ng Southeast University Nanjing 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

Selection of unitary operations in quantum secret sharing without entanglement

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science china(information sciences) 2011年第9期54卷 1837-1842页

作者： XU Juan 1,CHEN HanWu 1,LIU WenJie 1,2 & LIU ZhiHao 1 1 school of Computer science and engineer.ng,southeast university,nanjing 210096,china 2 school of Computer and Software,nanjing university of information science and Technology,nanjing 210044,china school of Computer science and engineer.ng Southeast University Nanjing China school of Computer and Software Nanjing University of Information Science and Technology Nanjing China

We propose a substitute-Bell-state attack strategy for quantum secret sharing schemes without entanglement,as well as a definition of the minimum failure probability of such attack strategy.A quantitative analysis of security degrees corresponding to different unitary operations is also provided,when the secret sharing schemes without entanglement are stricken by substitute-Bell-state *** a result,the relation between the selection of unitary operations and the effect of substitute-Bell-state attack is shown,which can serve as an important guidance for the selection of unitary operations in designing and implementing quantum secret sharing schemes.

关键词： quantum secret sharing substitute-Bell-state attack unitary operation minimum failure probability

Color image enhancement based on HVS and PCNN

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science china(information sciences) 2010年第10期53卷 1963-1976页

作者： ZHAng YuDong, WU LeNan , WAng ShuiHua & WEI Geng school of information science & engineer.ng, southeast university, nanjing 210096, china school of information science & engineer.ng Southeast University Nanjing China

To enhance color images more effectively, a novel strategy is presented in this paper. We firstly translate the image to be enhanced from RGB space into HIS space, secondly keep its H component unchanged, and thirdly stretch its S component exponentially, and at last process its I component in the following manner: couple both the gray value and the spatial information into an inner activity item of corresponding neuron, integrate the human visual system into a dynamic component of corresponding neuron, and compare the inner activity item with dynamic component to obtain the enhanced image. Experiments demonstrate the effectiveness and validity of our strategy.

关键词： image enhancement human visual system (HVS) pulse coupled neural network (PCNN) color image

ORDERED WEIGHTED DISTANCE MEASURE

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Journal of Systems science and Systems engineer.ng 2008年第4期17卷 432-445页

作者： Zeshui XU~1 Jian CHEN~2 1 school of Economics and Management,southeast university,nanjing,Jiangsu 210096,china 2 school of Economics and Management,Tsinghua university,Beijing,100084,china school of Economics and Management Southeast University Nanjing Jiangsu China school of Economics and Management Tsinghua University Beijing China

The aim of this paper is to develop an ordered weighted distance(OWD) measure,which is the generalization of some widely used distance measures,including the normalized Hamming distance, the normalized Euclidean distance,the normalized geometric distance,the max distance,the median distance and the min distance,***,the ordered weighted averaging operator,the generalized ordered weighted aggregation operator,the ordered weighted geometric operator,the averaging operator,the geometric mean operator,the ordered weighted square root operator,the square root operator,the max operator,the median operator and the min operator are also the special cases of the OWD *** methods depending on the input arguments are given to determine the weights associated with the OWD *** prominent characteristic of the OWD measure is that it can relieve(or intensify) the influence of unduly large or unduly small deviations on the aggregation results by assigning them low(or high) *** desirable characteristic makes the OWD measure very suitable to be used in many actual fields,including group decision making,medical diagnosis, data mining,and pattern recognition,***,based on the OWD measure,we develop a group decision making approach,and illustrate it with a numerical example.

关键词： Group decision making ordered weighted distance(OWD) measure aggregation operator

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 Research Laboratory, school of information science and engineer.ng, southeast university, nanjing 210096, china National Mobile Communication Research 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.

Heuristic for no-wait flow shops with makespan minimization based on total idle-time increments

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science in china(Series F) 2008年第7期51卷 896-909页

作者： LI XiaoPing1,2 & WU Cheng3 1 school of Computer science & engineer.ng, southeast university, nanjing 210096, china 2 Key Laboratory of Computer Network and information Integration (southeast university), Ministry of Education, nanjing 210096, china 3 Department of Automation, Tsinghua university, Beijing 100084, china school of Computer science & engineer.ng Southeast University Nanjing China Key Laboratory of Computer Network and information Integration (southeast university) Ministry of Education Nanjing China Department of Automation Tsinghua University Beijing China

No-wait flow shops with makespan minimization are classified as NP-hard. In this paper, the optimization objective is equivalently transformed to total idle-time minimization. The independence relationship between tasks is analyzed, and objective increment properties are established for the fundamental operators of the heuristics. The quality of the new schedules generated during a heuristic is judged only by objective increments and not by the traditional method, which computes and compares the objective of a whole schedule. Based on objective increments, the time complexity of the heuristic can be decreased by one order. A seed phase is presented to generate an initial solution according to the transformed objective. Construction and improvement phases are introduced by experimental analysis. The FCH （fast composite heuristic） is proposed and compared with the most effective algorithms currently available for the considered problem. Experimental results show that the effectiveness of the FCH is similar to that of the best methods but requires far less computation time. The FCH can also be efficient in real time scheduling and rescheduling for no-wait flow shops.

关键词： no-wait flow shops heuristic makespan Tabu search

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Non-blocking message total ordering protocol

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science in china(Series F) 2008年第12期51卷 1919-1934页

作者： WAng Yun & WAng JunLing school of Computer science & engineer.ng, southeast university Key Lab of Computer Network & information Integration, MOE, nanjing 210096, china school of Computer science & engineer.ng Southeast University Key Lab of Computer Network & information Integration MOE Nanjing China

Message total ordering is a critical part in active replication in order to maintain consistency among members in a fault tolerant group. The paper proposes a non-blocking message total ordering protocol （NBTOP） for distributed systems. Non-blocking property refers to that the members in a fault tolerant group keep on running independently without waiting for installing the same group view when a fault tolerant group evolves even when decision messages collide. NBTOP takes advantage of token ring as its logical control way. Members adopt re-requesting mechanism （RR） to obtain their lost decisions. Forward acknowledgement mechanism （FA） is put forth to solve decision collisions. The paper further proves that NBTOP satisfies the properties of total order, agreement, and termination. NBTOP is implemented, and its performance test is done. Comparing with the performance of Totem, the results show that NBTOP has a better total ordering delay. It manifests that non-blocking property helps to improve protocol efficiency.

关键词： total ordering protocol non-blocking active replication fault tolerance token ring

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Three-dimensional subwavelength components utilizing THz surface plasmons

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science china(information sciences) 2012年第1期55卷 79-89页

作者： ZHOU YongJin,JIAng Quan&CUI TieJun State Key Laboratory of Millimeter Waves,school of information science and engineer.ng,southeast university,nanjing 210096,china State Key Laboratory of Millimeter Waves School of Information Science and Engineering Southeast University Nanjing China

Since surface plasmons(SPs)are not constrained by the diraction limit,they have important potential applications in the optical,terahertz(THz),and microwave *** this paper,we firstly present a review of three-dimensional(3D) bidirectional and multi-directional THz SP splitters based on the rectangular metallic groove gratings with finite thickness,in which a metallic wire was used to excite the THz *** experimental verifications of such splitters have been implemented in the microwave frequencies,and the measurement results have excellent agreements to the full-wave *** improve the performance,a 3D bidirectional THz SP splitter with the transverse confinement and a 3D bidirectional bending THz SP splitter are then proposed,which have shown very good splitting performance,compact sizes,and better transverse confinement of EM ***,a broadband slow-wave system of subwavelength thickness is reviewed and a new bending slow-wave system utilizing THz SPs is *** and simulations in microwave frequencies have good agreements,showing the validity of these components.

关键词： surface plasmons surface waves terahertz slow wave splitter