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Pseudo-Random Sequences Generator Based on Discrete Hyperchaotic Systems

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Journal of Systems engineering and Electronics 2003年第4期14卷 84-89页

作者： Li Changgang & Han Zhengzhi Department of Automation, shanghai jiaotong university, shanghai 200030, P. R. china Department of Automation Shanghai Jiaotong University Shanghai 200030 P. R. China

We first design a discrete hyperchaotic system via piece-wise linear state feedback. The states of the closed loop system are locally expanding in two directions but absolutely bounded on the whole, which implies hyperchaos. Then, we use three suchlike hyperchaotic systems with different feedback gain matrices to design a pseudo-random sequence generator (PRSG). Through a threshold function, three sub-sequences generated from the output of piecewise linear functions are changed into 0-1 sequences. Then, followed by XOR operation, an unpredictable pseudo-random sequence (PRS) is ultimately obtained. The analysis and simulation results indicate that the PRS, generated with hyperchaotic systems, has desirable statistical features.

关键词： discrete hyperchaotic system piecewise linear state feedback pseudo-random sequences.

Forecasting of Stock Returns by Using Manifold Wavelet Support Vector Machine

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Journal of shanghai jiaotong university(science) 2010年第1期15卷 49-53页

作者：汤凌冰盛焕烨汤凌霄 Department of computer science and engineering Shanghai Jiaotong University Department of computer and Electronic engineering Hunan Business College School of Economics Changsha University of Science & Technology

An admissible manifold wavelet kernel is proposed to construct manifold wavelet support vector machine(MWSVM) for stock returns *** manifold wavelet kernel is obtained by incorporating manifold theory into wavelet technique in support vector machine(SVM).Since manifold wavelet function can yield features that describe of the stock time series both at various locations and at varying time granularities,the MWSVM can approximate arbitrary nonlinear functions and forecast stock returns *** applicability and validity of MWSVM for stock returns forecasting is confirmed through experiments on real-world stock data.

关键词： stock returns forecasting kernel manifold wavelet support vector machine (MWSVM)

Parallel-pipelined Architecture of H.264 Deblocking Filter with Adaptive Dynamic Power

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Journal of shanghai jiaotong university(science) 2010年第2期15卷 224-230页

作者：韦虎林涛 Department of Electronic engineering Shanghai Jiaotong University Institute of Very Large Scale Integrated Circuits Tongji University

In H.264,the computational complexity and memory access of deblocking filter are variable and depend on the video contents. In this paper,a pipelined VLSI architecture of deblocking filter with adaptive dynamic power is proposed. It avoids redundant computations and memory access by precluding the blocks which can be skipped. And the vertical and horizontal edges are simultaneously processed in an advanced scan order to speed up the decoder. As a result,the dynamic power of the proposed architecture can be reduced (up to about 89%) adaptively for different videos. And the off-chip memory access is improved compared to the previous designs. Moreover,the processing capability of the proposed architecture is very appropriate for real-time deblocking of high-definition television (HDTV,1920× 1080 pixel/frame,30 frame/s video signals) video operation at 38 MHz,which significantly outperforms the previous designs from 1.25 times to 4.8 times.

关键词： deblocking filter adaptive dynamic power parallel processing pipeline H.264

Underwater Digital Terrain Model with GPS-aided High-resolution Profile-scan Sonar Images

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Journal of shanghai jiaotong university(science) 2008年第2期13卷 233-238页

作者：周拥军寇新建 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

The whole procedures of underwater digital terrain model (DTM) were presented by building with the global positioning system (GPS) aided high-resolution profile-scan sonar *** algorithm regards the digital image scanned in a cycle as the raw *** the label rings are detected with the improved Hough transform (HT) method and followed by curve-fitting for accurate location;then the most probable window for each ping is detected with weighted neighborhood gray-level co-occurrence matrix;and finally the DTM is built by integrating the GPS data with sonar data for 3D *** case of an underwater trench for immersed tube road tunnel is illustrated.

关键词： digital terrain model high-resolution sonar Hough transform neighborhood gray-level co-occurrence matrix

An Improved Model Updating Method of Reduced-Models for Finite Element Model

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Journal of shanghai jiaotong university(science) 2010年第3期15卷 377-384页

作者：李伟明洪嘉振 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

Most of exiting model updating methods based on the substructure matrices did not consider the effect of model reduction process on model updating which led to the updating results could not become more and more accurate with the improvement of the model reduction precision and the convergence rate was greatly *** order to solve this problem,this paper analyses the basic reason about this problem,and proposes an improved model updating method of reduced-models,named as improved reduced cross-model cross-mode(IRCMCM) *** proposed method eliminates the disadvantageous effect by adding a correction term to the model updating formula and employing an iterative *** results obtained by the referenced method and IRCMCM method are compared by numerical examples of satellite's plates,which indicate the model updating results are more accurate by using the proposed method,and the model updating precision becomes better with the precision of the model reduction upgraded and the convergence rate is improved to a large extent at the same time.

关键词： finite element method model updating model reduction iteration

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一个高效安全的身份基加密方案

上海交通大学学报 2010年第3期44卷 389-392页

作者：马融曹珍富上海交通大学计算机科学与工程系上海200240

针对身份基加密方案效率和安全性不高的问题,利用"双胞胎"技术,提出了一个加密时只需使用一次配对的新方案.研究结果表明,该方案可以在随机预言模型下紧规约到标准难题,是具有适应性选择密文安全的身份基加密方案.

关键词：身份基加密紧规约选择密文安全随机预言模型

NUMERICAL SIMULATION OF THE DISPERSION IN OSCILLATING FLOWS WITH REVERSIBLE AND IRREVERSIBLE WALL REACTIONS

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Journal of Hydrodynamics 2009年第4期21卷 482-490页

作者： ZHANG Dao-xiang LU Zhi-ming LIU Yu-lu NG Chiu-On shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China College of Mathematics and computer science Anhui Normal University Wuhu 241000 China Department of Mechanical engineering The University of Hong Kong Hong Kong China

This is a study on the mass transport of a solute or contaminant in oscillating flows through a circular tube with a reactive wall layer. The reaction consists of a reversible component due to phase exchange between the flowing fluid and the wall layer, and an irreversible component due to absorption into the wall. The short-time dispersion characteristics are numerically investigated, incorporating the coupling effects between the flow oscillation, sorption kinetics, and retardation due to phase partitioning. The effects of various dimensionless parameters e.g., Da （the Damkoehler number）, α （phase partitioning number）, F （dimensionless absorption number）, and δ （dimensionless Stokes boundary layer number） on dispersion are discussed. In particular, it is found that there exist trinal peaks of the breakthrough curves in some cases.

关键词： dispersion flow oscillation wall reactions

A New Method of Transmission Network Flexible Planning Using the Connection Number

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Journal of shanghai jiaotong university(science) 2008年第4期13卷 436-442页

作者：金华征程浩忠 Department of Electrical engineering Shanghai Jiaotong University

Because connection number can express and process synthetic uncertainties caused by various uncertainties in the transmission network planning, a connection number model (CNM) was presented to compare the values of connection number logically. This paper proposed a novel model for transmission network flexible planning with uncertainty. In the proposed planning model both certainty and uncertainty information were included, and the cost-benefit analysis method was used to evaluate the candidate schemes in the objective function. Its good adaptability and flexibility were illustrated through two examples.

关键词： transmission network planning uncertainty flexible planning connection number connection number model (CNM) blind number

Periods and Energy Dissipations of a Novel TLD Rectangular Tank with Angle-adjustable Baffles

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Journal of shanghai jiaotong university(science) 2008年第2期13卷 139-144页

作者：尚春雨赵金城 Department of Civil engineering Shanghai Jiaotong University

A novel tuned liquid damper (TLD) rectangular tank with two angle-adjustable baffles was pre- *** numerical analysis was performed using the commercial code *** standard kinetic energy and dissipation rate turbulent model was employed,which was solved using volume of fluid (VOF) method able to treat both the free surface motion and the viscous stresses over the rigid walls *** relationship between the natural periods of water and the angles of its baffles was studied by numerical sim- ulating of a case,and the changes of energy dissipations were *** natural periods and dampers of the novel TLD can be changed in a wide range by adjusting the baffles' angle,thus it is more effective in controlling the vibration of structures in a wide frequency range.

关键词： tuned liquid damper angle-adjustable baffle turbulent eddies energy dissipation