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    Development of IT Industry in China in the New Age
    JIANG Ze-min
    Journal of Shanghai Jiaotong University   
    Abstract17096)            Save
    The article explains the role and future trend of IT industry, and states that information technology represented by the internet and computers has brought about the third industrial revolution in history. An important impetus for economic growth in modern times, the IT industry has greatly promoted sustainable development and is profoundly changing mankind’s way of life and production. In discussing the development trend of world IT industry, the article suggests that with potential new breakthroughs in IT technology, the trend of agglomeration and integration of industries has become increasingly obvious, competition of intellectual properties and strandards is intensifying and ubiquitous networks is taking shape. It points out that China should bring into better play the role of IT industry as an “amplifier” in economic growth, a “transformer” in development mode and a “propeller” in industrial upgrading. It is important to follow a policy that emphasizes indepandent innovation, marketdriven approach, open and compatible technologies, integrated and comprehensive application, and serving both military and civil purposes, so that a quantum leap of IT industry will be achieved. China should advance industrialization with IT technologles and promote the IT industry in the course of industrialization in an effort to build an IT industry with Chinese characteristics. Greater efforts should be made to develop such core sectors as microelectronics, computer, software, key components and materials, as well as sectors with international competitiveness, including broadband mobile communication, nextgeneration network and information services. Continued improvement should be made in the policies guiding the development of IT industry with a view to making China a country with a strong IT industry by 2020.
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    A Real-Time Lifetime Prediction Method Based on Wavelet Support Vector Regression Optimized by GA
    HU You-Tao, HU Chang-Hua
    Journal of Shanghai Jiaotong University    2011, 45 (08): 1216-1220.  
    Abstract12548)            Save
    Aiming at the fact that the present real-time lifetime prediction methods do not take full advantage of the same kind of products’ performance degradation data, as viewed from the comparability of degradation paths, a real-time lifetime prediction method was proposed on the basis of wavelet support vector regression (WSVR) optimized by genetic algorithm (GA). Firstly, GA-WSVR is employed to build the same kind of products’ performance degradation path models. Then the specific individual’s historical measure time vector is used as the benchmark, the same kind of products’ corresponded degradation measurement vectors are calculated using GA-WSVR models. The Euclid distances of the specific individual and the same kind of products are used to determine degree of membership, so the individual’s degradation path model is built on the basis of degree-of-membership weighted method. Finally, the measurement vectors, Euclid distances, degree of membership and degradation path model are updated with real-time measurement data. The proposed method is applied to fatigue crack growth data, the experimental results validate the validity.
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    The IRBC Calculation for 2D Electrically Large Targets
    SONG Zhi-Qiang, LIU Peng
    Journal of Shanghai Jiaotong University    2011, 45 (12): 1863-1867.  
    Abstract11704)            Save
    Evaluation of Hankel functions of zeroth and first order arises in the finite element solution of two dimensional electromagnetic scattering problems as the iterative Robin boundary condition (IRBC) is used as the openregion boundary condition. In practice, approximation of these functions is required when the target is electrically large and the computation is very timeconsuming. In this paper, four approximation algorithms are first investigated, including series expansion, small and large argument approximation, and two different kinds of numerical methods. Then the accuracy and speed are compared in the computation of IRBC. The small and large argument approximation, combined with a certain numerical method is shown to be very effective. Some examples of electrically large size are also presented.
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    Local Extreme Learning Machine and Its Application to Condition Online Monitoring
    ZHANG Xian,WANG Hongli
    Journal of Shanghai Jiaotong University   
    Abstract10994)            Save
    To reduce the computational cost of extreme learning machine (ELM) online training, a new algorithm called local extreme learning machine (LELM) was proposed. LELM adopts the latest training sample and abandons the oldest training sample iteratively to insure that only the most relevant samples are applied to LELM online training. The output weights of LELM are determined recursively during each training procedure to reduce the computational cost of online training. The numerical experiments on chaotic time series prediction indicate that the online training computational cost of LELM is much less than that of ELM. The numerical experiments on radar transmitter condition online monitoring based on time series prediction indicate that LELM has better performance in online training computational cost and prediction accuracy in comparison with conventional electronic system condition online monitoring method using adaptive grey model.
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    Boiling Heat Transfer Characteristics of Nanofluids in  a Thermosyphon Loop
    LIU Zhen-Hua, YANG Xue-Fei
    Journal of Shanghai Jiaotong University    2011, 45 (06): 890-894.  
    Abstract10397)            Save
    An experimental study was performed to understand the boiling characteristics of CuOwater nanofluids in a thermosyphon loop. Experiments were carried at varied subatmospheric pressures. Effects of the mass concentration and the operating pressure on the heat transfer characteristics were mainly discussed. The results indicate that nanofluids can enhance both the boiling heat transfer coefficient (HTC) and the critical heat flux(CHF). The effect of the operating pressure on the heat transfer coefficient is obvious, while the effect is weak on CHF. There exists an optimal mass concentration of nanoparticles, which corresponds to the largest HTC enhancement. The HTC enhancement results from the effects of both the coating layer and the working fluids. The CHF enhancement results mainly from the coating layer formed by nanoparticles during the heating process.
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    Numerical Simulation of Sink-Stability for Unmanned Underwater Lurk Vehicle
    PAN Guang, SHI Yao, DU Xiao-Xu, HUANG Qiao-Gao
    Journal of Shanghai Jiaotong University    2012, 46 (09): 1493-1497.  
    Abstract10382)            Save
      The sink-stability of unmanned underwater lurk vehicle (UULV) was studied by using the computational fluid dynamics. First, the hexahedral mesh of the UULV in different sinking model was generated by ICEM CFD. Then the variation tendency of lateral force,lift force and rolling moment under different submarine speeds was gotten by using CFX. Based on the force analysis a mathematical model for the analysis of sink-UULV was established. Last, the effect of submarine speed and sinking model on UULV’s sink-stability was gotten through combining the numerical simulation’s result with that of math model. The result shows that the UULV can remain stable under 0.514 m/s submarine speed, it will be rollingover when the speed is equal to or greater than 1.028 m/s.  
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    Efficient Implementation of Real-Time PFFT Processor Based on FPGA
    LING Xiao-Feng, GONG Xin-Bao, JIN Rong-Hong
    Journal of Shanghai Jiaotong University    2012, 46 (11): 1811-1815.  
    Abstract8809)            Save
    A novel efficient processor for computing the real-time discrete Fourier transform (DFT) on programmable field programmable gates array (FPGA) devices was presented. Prime factor Fourier transform (PFFT) algorithm was implemented in the proposed processor. Pipelined architecture was applied to maintain the realtime performance of the processor. Distributed arithmetic based on Look-up-table (LUT) was exploited to adapt to the basic logic cell of the FPGA. Cyclic convolution feature of the prime length DFT was used to significantly reduce the scale of LUTs. Based on the proposed method, a real-time 1 105-point processor with 16 bits precision was designed and implemented on Xilinx Virtex5 FPGA platform. Compared with existing real-time 1 024-point processors, the proposed processor consumes fewer resources while obtaining more efficient utilization of the resources.  
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    Distributed Beamforming Schemes Based on QR Decomposition and SIC Detection for MIMO Relay Networks
    HUANG Zi-Li, JIANG Ling-Ge, HE Chen
    Journal of Shanghai Jiaotong University    2012, 46 (11): 1826-1832.  
    Abstract8629)            Save
    This paper is concerned with a two hop half-duplex wireless communication network with multiple antennas and multiple relays. Based on amplifyandforward (AF) protocol, two new distributed beamforming schemes named IRZF-MF and RZF were proposed for this system. The RZF scheme uses RZF technique for both receive and transmit beamforming while the IRZF-MF scheme uses IRZF and MF technique for receive and transmit beamforming respectively. The simulation results show that the proposed two relay schemes achieve the same performance of existing MF-RZF scheme in the Rayleigh channel, meanwhile, the proposed RZF scheme achieves the best performance which requires a higher computational complexity and the proposed IRZFMF scheme achieves the second best performance while requires less computational complexity than RZF scheme in the Rician channel compared with other existing distributed relaying schemes. Key words:
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    Preparation and Characteristics Analysis of Friction and Wear Behavior of MPTS/MPTES Composition Selfassembled Film
    XU Ying1,2,ZHOU Hua1,CHENG Xianhua2
    Journal of Shanghai Jiaotong University   
    Abstract7462)            Save
    MPTS/MPTES selfassembled film was fabricated on singlecrystal silicon substrates by molecular selfassembly process. Atomic force microscope (AFM), Xray photoelectron spectrometry (XPS) and contact angle measurer were used to characterize the thin films. The tribological properties of the films sliding against GCr15 steel ball were evaluated on a DFPM reciprocating friction and wear tester. The results show that the MPTS/MPTES film has excellent hydrophobic and friction and wear behavior properties compared with MPTS film and MPTES film. The cause is that the MPTS/MPTES film has big size molecule which can endow some fluidity and flexibility to the film and closepacked molecules or radicals on the bottom are rigid which can bear certain load.
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    Universal Shop Scheduling Method for Manufacturing System
    with Evolution Algorithm
    HU Yan-hai1, 2, YAN Jun-qi1, MA Deng-zhe1 ,YE Fei-fan2
    Journal of Shanghai Jiaotong University   
    Abstract6799)            Save
    The concept of universal shop scheduling problem (USP) was proposed based on the analysis of a real production system. A hybrid ant colony optimization (HACO) was developed to be applied to the USP. The results were compared with those of genetic algorithm. The numerical experiments make use of several benchmark instances whose scale is up to 75×20. Minimizing makespan is taken as the objective function. Both termination conditions of computation generation and solution convergence are tested for the computation. From the numerical experiments, it can be seen that when the computation generation is kept the same, HACO will make the solutions more convergent, and when the convergency is kept the same, HACO will consume less time.
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    Saliency Detection Based on Phase Spectrum of Color Information
    LI Wu-yue1, LI Zhi-qiang1, FANG Tao1, HUO Hong1, GE Wei-li2
    Journal of Shanghai Jiaotong University   
    Abstract6776)            Save
    It is still a challenge to build a computing model of saliency detection by simulating the complex human vision system. Combining the characteristics of human visual system and previous studies in saliency, a saliency detection model based on phase spectrum of color information was proposed. A saliency map, in which the regions of important targets are pop out, was generated by using the proposed model. The experimental results indicate that the saliency regions in complex scene detected by our method are consistent with the attention regions of human vision in bottomup stage.
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    A Nonlinear Inverse Perspective Transform Based Method for Camera Distortion Calibration
    LI Hao, YANG Ming
    Journal of Shanghai Jiaotong University   
    Abstract6684)            Save
    Camera distortion calibration plays an indispensable role in the research of robot vision. A nonlinear inverse perspective transform based method was proposed. In the light of linear perspective model and distortion model, a nonlinear inverse perspective model as well as the relation between inverse perspective transform coefficients and distortion coefficients was derived. A function with distortion coefficients as the optimum was put forward and optimized. Because only few distortion coefficients are optimized, the optimization dimension and complexity are largely reduced. During optimization, the search direction is determined by improved Newton method and a try and error linear search method is carried out along the search direction. Both the simulation and experiments verify the effectiveness and high accuracy of the method.
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    Genetic Algorithm to Solve Optimization Problem with Equality Constrains
    HU Kuan-1, 2 , CHANG Xin-Long-1, SONG Bi-Feng-2, ZHANG Lin-3, LONG Bing-1, YU Yan-Feng-1
    Journal of Shanghai Jiaotong University    2011, 45 (07): 966-969.  
    Abstract6636)            Save
    Aiming at difficultly solving optimization with equality constraint in genetic algorithm, based on independence analysis of design variables, a descending dimension method was used to deal with equality constraint. In this way, not only equality constraints can be strictly satisfied during optimization, but also there are only inequality constrains in optimization. Furthermore, referring to the multiobjective idea, individuals was ranked through violation degree and violation times simultaneously, which is more in accord with practice. Finally, three numerical examples were used to examine the proposed method, satisfying results were achieved, which indicates the method is valid and feasible.
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    A 3D Human Body Modeling Method Based on Neural Network
    DENG Wei-yan,LU Guo-dong,GENG Yu-lei,WANG Jin
    Journal of Shanghai Jiaotong University   
    Abstract6619)            Save
    A method of 3D human body modeling was presented. The model of fourlayer feed forward BP(backpropagation) neural network was given. By making use of scanned body data, cutting planes were allocated to get the feature points of section contours of scanned body, and the training samples of the neck, bust, waist and hip were obtained. The weight and the feature curve modeling of the neck, bust, waist and hip can be got respectively after training. Based on section loops which generate from neural network, a 3D manikin was regenerated. Finally, the error analysis was done and the results show that the method can approach the real human body feature curve. It is an effective modeling way for the human body.
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    Ant Algorithm for Lot Sequencing in Wafer Fabrication System
    YAO Shi-qing, JIANG Zhi-bin, GUO Cheng-tao, HU Hong-tao
    Journal of Shanghai Jiaotong University   
    Abstract6523)            Save
    Lot sequencing optimization based on ant algorithm, which solves choosing lots from buffers to be processed in semiconductor wafer fabrication system (SWFS), was proposed. Furthermore, time complexity of this algorithm was analyzed and the improved form was given. According to the characteristics of reentrant in SWFS, the algorithm was designed through constructing the model of ant algorithm based on bottlenecks, and eventually Lot priority sequencing was obtained by iterative simulation. It can be seen from the simulation result that the new algorithm is superior to common dispatching rules in shortterm scheduling.
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    Property Investigation of a-Si/c-Si Hetero-Junction Structure
    WANG Jian-Qiang-1, 2 , GAO Hua-2, ZHANG Jian-2, ZHANG Song-1, LI Chen-1, YE Qing-Hao-1, MENG Fan-Ying-1
    Journal of Shanghai Jiaotong University    2011, 45 (06): 798-803.  
    Abstract6497)            Save
    This paper investigated the influence of a-Si/c-Si band offset, amorphous silicon emitter doping concentration and interface defects density on interface property of a-Si/c-Si structure. Band offset in a-Si(N+)/c-Si(P) hetero-junction and a-Si emitter high level doping is very useful for the transformation of recombination mechanism from dangling bond to SRH(Shockly-Read-Hall). AFORS-HET simulation indicates that a-Si(N+) emitter doping level of over 1.5×1020 cm-3 on c-Si(P) is an indispensable condition for achieving high efficiency. Comparing with density of short circuit current, open circuit voltage of a-Si/c-Si structure cell is much more susceptible to interface defect density.
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    An Adaptive Sampling Algorithm Based on Vector Field for Medical Volume Rendering
    TANG Wei, YAO Li-xiu, YANG Jie, QIN Hong-xing
    Journal of Shanghai Jiaotong University   
    Abstract6273)            Save
    Aiming at the characteristic of medical volume rendering, this article studied the variety of vector field of data, analyzed the relationship between the grads vector field of the medical volume data set and the sampling frequency, then proposed an adaptive sampling algorithm, in which the volume area that is more to contribute to the final image would be sampled with highfrequency, and in a relative manner, the volume area that is less to contribute to the final image would be sampled with lowfrequency. In this way, the sampling step is adjusted adaptively, and the performance of volume reconstruction is improved. The experiments show that the performance of the volume reconstruction is improved by about 30%~60%, while the quality of image is ensured.
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    Robust Deformable Medical Image Registration Using Optical Flow and Multilevel Free Form Deformation
    WANG Min-you, HU Hai-bo, QIN Bin-jie
    Journal of Shanghai Jiaotong University   
    Abstract6266)            Save
    In order to track the brain tissue shift due to tumor resection during image guided surgery, this paper presented a framework for robust deformable registration based on the theory of optical flow, within which outlier detection is used to set up locallyrefined control points in multilevel free form deformation (FFD) model. Robust Mestimator was also introduced to weaken the effect of outliers in global optimization for getting improved registration result. This proposed method has successfully been applied to a number of registration tasks to demonstrate its applicability and robustness to outliers.
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    Robot Workcell Layout Optimization Based on Genetic Algorithm
    XIANG Bin-bin1,CHEN Wei-dong1,QI Li-wei2,ZHANG Dan-dan2
    Journal of Shanghai Jiaotong University   
    Abstract6233)            Save
    This paper proposed a robot workcell layout optimization method based on genetic algorithm. This method applies engineer’s experience and knowledge in robotic manufacturing system to the description of geometric and kinematic restrictions, thus reduces search space, improves the computational efficiency and makes the layout meet the industrial requirements better. The method has been embedded in commercial robot programming and simulating software, and used successfully in layout design. A diecast application case validates the effectiveness of the method.
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    A Parallel Collisions Detection Algorithm for Interactive Assembling Operation in Virtual Environment
    WU Dian-liang1,2, ZHU Hong-min1,2, FAN Xiu-min1,2
    Journal of Shanghai Jiaotong University   
    Abstract6218)            Save
    Collision detection is a key technology in interactive virtual assembling operation. A new rapid collision detection algorithm for interactive operation in virtual reality (VR) environment was presented. It is an improved method of the conventional BV hierarchies method. According to the algorithm, a new method is used to compute BV hierarchies using regions partitioning on a polygonal model and a rapid overlapping check between facets and a BV. According to user’s operation collision detection pairs are determined; a parallel method based on PCs and Local Area Net (LAN) is developed to detect the collisions among many virtual objects. A method for dynamically modification hierarchies is developed for detecting overlapping between two BV hierarchies models. The performance of the algorithm is verified by means of an automobile underchassis assembling. The result shows that the method is applicable for all general polygonal models and can detecting overlapping during realtime simulation.
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