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Development of IT Industry in China in the New Age JIANG Ze-min Journal of Shanghai Jiaotong University    Abstract （16793）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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.   Abstract （12512）            Knowledge map    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. Reference | Related Articles | Metrics | Comments（0）

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TDRM: A Peer-to-Peer-Based Taxonomy Data Ring Model QIAO Bai-you (乔百友), WEI Yong (魏勇), WANG Xiao-yang (王潇杨) DING Lin-lin (丁琳琳), WANG Guo-ren (王国仁) Journal of shanghai Jiaotong University (Science)    2012, 17 (2): 182-189.   DOI: 10.1007/s12204-012-1250-8 Abstract （11795）            Knowledge map    Save Peer-to-peer (P2P) networks are widely used due to their good scalability and robustness. This paper considers the characteristics of data sources which use some taxonomy hierarchies to classify and organize their data objects, combines P2P techniques, and proposes a P2P based taxonomy data ring model (TDRM). The model makes full use of the semantic information contained in taxonomy hierarchies, places the data objects having similar semantics together, and organizes them into one dimensional ring structure. Super-peers dynamically join the ring according to the requirement. The routing connections among super-peers are created, which are similar to Chord ring, thus a semantics based structured super-peer network is formed. Experiments show that the model has good scalability and search efficiency. Reference | Related Articles | Metrics | Comments（0）

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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.   Abstract （11687）            Knowledge map    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. Reference | Related Articles | Metrics | Comments（0）

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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    Abstract （10961）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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.   Abstract （10382）            Knowledge map    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. Reference | Related Articles | Metrics | Comments（0）

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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.   Abstract （10350）            Knowledge map    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.   Reference | Related Articles | Metrics | Comments（0）

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Journal of Diagnostics Concepts & Practice    2021, 20 (04): 317-337.   DOI: 10.16150/j.1671-2870.2021.04.001 Abstract （9970）   HTML （544）    PDF（pc） （3337KB）（9571）       Knowledge map    Save Table and Figures | Reference | Related Articles | Metrics | Comments（0）

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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.   Abstract （8784）            Knowledge map    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.   Reference | Related Articles | Metrics | Comments（0）

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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.   Abstract （8609）            Knowledge map    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： Reference | Related Articles | Metrics | Comments（0）

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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    Abstract （7417）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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Simple Three-Party Password Authenticated Key Exchange Protocol LO Nai-wei (罗乃维), YEH Kuo-hui (叶国晖) Journal of shanghai Jiaotong University (Science)    2011, 16 (5): 600-603.   DOI: 10.1007/s12204-011-1195-3 Abstract （6771）            Knowledge map    Save Abstract:  Three-party password authenticated key exchange (3PAKE) protocol plays a significant role in the history of secure communication area in which two clients agree a robust session key in an authentic manner based on passwords. In recent years, researchers focused on developing simple 3PAKE (S-3PAKE) protocol to gain system efficiency while preserving security robustness for the system. In this study, we first demonstrate how an undetectable on-line dictionary attack can be successfully applied over three existing S-3PAKE schemes. An error correction code (ECC) based S-3PAKE protocol is then introduced to eliminate the identified authentication weakness. Reference | Related Articles | Metrics | Comments（0）

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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    Abstract （6770）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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    Abstract （6757）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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A Nonlinear Inverse Perspective Transform Based Method for Camera Distortion Calibration LI Hao, YANG Ming Journal of Shanghai Jiaotong University    Abstract （6659）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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    Abstract （6587）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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.   Abstract （6534）            Knowledge map    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. Reference | Related Articles | Metrics | Comments（0）

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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    Abstract （6488）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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.   Abstract （6425）            Knowledge map    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. Reference | Related Articles | Metrics | Comments（0）

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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    Abstract （6245）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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    Abstract （6241）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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    Abstract （6215）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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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    Abstract （6196）            Knowledge map    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. Related Articles | Metrics | Comments（0）

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Threshold Constraint Based DepthFirstSearch for BranchBound Algorithm Solving Asymmetric Traveling Salesman Problems ZHU Yi, YANG Gen-ke, PAN Chang-chun Journal of Shanghai Jiaotong University    Abstract （6116）            Knowledge map    Save An integration approach based on heuristic strategies and branchbound algorithm was proposed for solving asymmetric traveling salesman problem. In this method, associated with each node of the branchdecision tree, a parametric solution of the relaxed assignment problem and a feasible solution obtained by patching algorithm are used to tighten the lower and upper bound. A hueristic strategy that conbines the threshold constraint based depthfirstsearch and weighted random breadthsearch is adopted to seek the optimal solution. Therefore, a feasible solution that is very close to the optimal solution can be found in comparatively short time. The computational results on data in the TSPLIB and a hot strip scheduling simulation show the efficiency of the proposed algorithm. Related Articles | Metrics | Comments（0）

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3D Modeling and Motion Estimation of Elastic Articulated Objects from Image Points PAN Hai-lang1, SHI Lei2, DAI Yue-wei1 Journal of Shanghai Jiaotong University    Abstract （6099）            Knowledge map    Save This paper presented a new method of elastic articulated objects (human bodies) modeling based on a new revolving conic surface. The model includes 3D object skeleton and deformable surfaces which can represent the deformation of human body surfaces. The deformation of human body surfaces can be represented by adjusting only one deformation parameter for each limb. Then, the 3D deformation and motion parameters are determined by corresponding 2D image points with volume invariable constraint from a sequences of stereo images. The algorithm presented in this paper includes motion parameter estimation of the skeleton and parameter determination of deformable surface. Related Articles | Metrics | Comments（0）

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Study on Integrated Management of Marine Remote Sensing Data TENG Long-mei1,2，LIU Ren-yi2，LIU Nan2 Journal of Shanghai Jiaotong University    Abstract （6071）            Knowledge map    Save This paper put forward an integrated management method of marine remote sensing data by integrating the technologies of WebGIS, spatial database and network communication. A realtime publication of marine remote sensing data was designed and realized which integrates the function of data browsing, data querying, data downloading, automatic batch uploading remote sensing data to database, automatic longdistance data distribution and so on. The network communication technology and the efficient and safe data transmission that is combination of the encryption and verification technology were discussed. The mechanism of doubleeffect database connection pool was also analyzed. The strategy was proposed that marine remote sensing data is visualized by integrating the technology of creating data files dynamically with the technology of visualization cache. Finally, the application results show the system can manage marine remote sensing data efficiently. Related Articles | Metrics | Comments（0）

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Steadystate Objective Calculation for Constrained Predictive Control Systems Based on Goal Programming ZHENG Yi, WANG Bai-ping, LI Shao-yuan Journal of Shanghai Jiaotong University    Abstract （6059）            Knowledge map    Save In the procedure of steadystate objective calculation, the soft constraints adjustment and objective relaxation were required for getting satisfying results when the optimization problem is infeasible. The goal priority factor was introduced to describe the priority of the constraints and objectives; thereby the soft constraints adjustment and objectives coordination were solved systemically in realtime steadystate objective calculation. Simulation was processed with the example of the shell heavy oil fractionators benchmark problem, and the result shows the validity of the proposed algorithm. Related Articles | Metrics | Comments（0）

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A Selective Video Content Encryption Algorithm Exploiting the Characteristics of H.264/AVC CABAC Entropy Encoder XIE Qiang, ZHENG Shi-bao, YU Xiao-jing Journal of Shanghai Jiaotong University    Abstract （5977）            Knowledge map    Save In order to solve the encryption computing efficiency and flexibility issues when applying traditional data cryptographic algorithms on video content protection, this paper proposed a new selective video content encryption algorithm which exploits the characteristics of H.264/AVC CABAC entropy encoder. By introducing pseudorandomization in CABAC entropy encoder’s binary arithmetic encoding stage, the new algorithm can employ the entropy encoder itself to fulfill the basic encryption operation. In the meantime, the video content data unit being encrypted can be selected flexibly according to its importance. The experimental results show that the proposed algorithm does not impair the compression efficiency of the entropy encoder, and the encrypted video stream hides the visual characteristics of the original video content successfully. Related Articles | Metrics | Comments（0）

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Experimental Study on Resistance Reduction of Displacement Type Deep-V Hull Model Using Stern Flap ZHENG Yi, DONG Wen-Cai, YAO Chao-Bang Journal of Shanghai Jiaotong University    2011, 45 (04): 475-480.   Abstract （5968）            Knowledge map    Save Model tests of kiloton displacement type deep V ship series using stern flap for resistance reduction were carried through. The flap chord varies from 0.010 Lwl to 0.023 Lwl, install angle changes from 3° to 10°, and the test speed range from Fr=0.12 to 0.52. The influence of ship speed, flap chord and install angle on resistance reduction rate and running trim were investigated based on test data. Optimized stern flap parameters with application range were obtained for this particular ship form. Reference | Related Articles | Metrics | Comments（0）

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Nucleate Pool Boiling Heat Transfer Characteristics of  Refrigerant/Oil Mixture with Diamond Nanoparticles ZHUANG Da-Wei-1, PENG Hao-2, HU Hai-Tao-1, DING Guo-Liang-1, ZHU Yu-1 Journal of Shanghai Jiaotong University    2011, 45 (06): 861-865.   Abstract （5949）            Knowledge map    Save  Nucleate pool boiling heat transfer characteristics of refrigerant/oil mixture with diamond nanoparticles were investigated experimentally. The refrigerant is R113 and the oil is VG68. The experimental conditions include a saturation pressure of 101.3 kPa, heat fluxes from 10 to 80 kW·m-2, nanoparticles concentrations in the nanoparticles/oil suspension from 0 to 15 %, and nanoparticles/oil suspension concentrations from 0 to 5 %. The experimental results indicate that the nucleate pool boiling heat transfer coefficient of R113/oil mixture with diamond nanoparticles is larger than that of R113/oil mixture by maximum of 63.4% under the present experimental conditions, and the enhancement increases with the increase of nanoparticles concentration in the nanoparticles/oil suspension and decreases with the increase of nanoparticles/oil suspension concentration. A correlation for predicting the nucleate pool boiling heat transfer coefficient of refrigerant/oil mixture with nanoparticles was proposed. The predicted values of the new correlation can agree with 94% of the experimental data of R113/oil mixture with diamond nanoparticles in the present study within the deviation of ±20%. Reference | Related Articles | Metrics | Comments（0）

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Study on the Choice of Disciplinal Function During Point Cloud Smoothing Based on Anisotropic Heat Diffusion ZHANG Xue-chang1, JIA Zhi-xin1, CHEN Xiao-bo2, XI Jun-tong2，YANG Guang-quan2 Journal of Shanghai Jiaotong University    Abstract （5900）            Knowledge map    Save The smoothing method based on the heat diffusion has a good effect to the point cloud with noise points, but how to choose a proper disciplinal function to smooth the point cloud is no answer. This paper proposed a method to decide the disciplinal function based on the fuzzy mathematics’s relevant function concept. The six special functions, such as drop semirectangle function, drop semiГ function, drop seminormal function, drop semiCauchy function, drop semitrapezia function and drop semimountain function, were analyzed. The answer was gotten that the variant has a nonlinear relationship with the result of disciplinal function. Some cases were used to validate the characteristics of disciplinal function. There is a new way to handle the point cloud during the preprocessing of reverse engineering or complex surface inspection. Related Articles | Metrics | Comments（0）

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Modeling of a Small Scale Unmanned Helicopter DU Jian-fu1, Lu Tian-sheng1, Konstantin Kondak2, ZHANG Ya-ou1 Journal of Shanghai Jiaotong University    Abstract （5848）            Knowledge map    Save Based on the analysis of the difference between small scale unmanned helicopters and normal scale helicopters, the small scale helicopter was modeled as two rigid bodies: fuselage and main tail rotor. The dynamical model was deduced by Kane method, and another model considering the helicopter as one rigid body was also deduced for comparison. It shows that the kinematics and translational dynamics are the same, but they have different rotational dynamics. The response of the dynamics modeled as two rigid body is cosine while the response of the dynamics modeled as one rigid body is linear. The real flight experiments verify the validity of the model. Related Articles | Metrics | Comments（0）

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Measurement Method and Compensation Control for Unbalanced Moment of Inertial Platform YU Shuang, FU Zhuang, ZHAO Hui, ZHAO Yan-zheng Journal of Shanghai Jiaotong University    Abstract （5848）            Knowledge map    Save A measurement and compensation method was proposed in order to eliminate the coupling effect on tracking accuracy and stabilizing capability due to unbalanced moment of inertial platform. The condition for static balancing of twoaxis gimbaled inertial platform was analyzed. Weight sensors were used to measure the static unbalance torque of inner and outer gimbal, then the calculation formulas of dynamic unbalanced moment during missile flight were derived. The simulation results of the built control model for inner gimbal in MATLAB/Adams show the effectiveness of the proposed compensation method for unbalanced moment. Related Articles | Metrics | Comments（0）

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Preventive Maintenance Modeling of Cluster Tools for Fabrication Wafers Based on Markov Chain ZHOU Bing-hai, HE Ping, PAN Er-shun, XI Li-feng Journal of Shanghai Jiaotong University    Abstract （5829）            Knowledge map    Save To improve the running reliability of cluster tools for fabrication wafers, and to reduce maintenance cost efficiently, a Markov chainbased modeling method for preventive maintenance was proposed. According to the characteristics of the cluster tools, five states are defined, such as the running state, preventive maintenance (PM) state, PM unrestore state, preventive repair (PR) state and PR unrestore state. A state transition model was built with the five states. On the basis of the proposed model, an expected preventive maintenance cost model was presented. Finally, the built model was tested with simulative experiment data. The results indicate that the Markov chainbased preventive maintenance model is valid for analyzing the expected maintenance cost rate per unit time according to different combinations of modeling parameters. Related Articles | Metrics | Comments（0）

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Fatigue Analysis of Offshore Wind Turbine Mono-pile Support Structure MO Ji-Hua, HE Yan-Ping, LI Yong-Gang, ZHANG Er-Hu Journal of Shanghai Jiaotong University    2011, 45 (04): 565-569.   Abstract （5789）            Knowledge map    Save WAsP was used to analyze the data of a wind farm and the wind speed distribution was gained. The parameters of wind, wave and current for each working condition were calculated. On the basis of fatigue loads, ABAQUS was used to model the support structure and the stress response time history was figured out through mode superposition method. According to S-N curves, rainflow counting method and Miner’s linear damage theory, Fe-safe was used to work out the fatigue life of the support structure and the effect of different kinds of loads on fatigue life was also researched. The results show that the fatigue life of the support structure meets demand. Wind turbine loads are the key influence factor of fatigue life. Sensible generator control strategy is good for increasing fatigue life. The method that defining working condition through wind direction and 10 minute mean wind speed can be used in fatigue analysis of offshore wind turbine support structure. Reference | Related Articles | Metrics | Comments（0）

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CHAI Xiang-hai, JIN Xian-long Journal of Shanghai Jiaotong University    Abstract （5782）            Knowledge map    Save Related Articles | Metrics | Comments（0）

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Precision Control Scheme and Experimental Analysis of Hydraulic Servo System with Large Friction Torque MIAO Zhong-hua，LIU Cheng-liang，WANG Xu-yong，LI Yan-ming Journal of Shanghai Jiaotong University    Abstract （5773）            Knowledge map    Save In order to obtain a high precision control performance for nonlinear hydraulic servo system in the presence of large frictional torque, a novel control scheme based on the slidingmode variable structure controller combined with friction state observer was presented. The slidingmodel variable structure control law and the slidingmodel friction state observer were detailed. The LuGre dynamic friction model and the sliding mode friction observer were adopted for friction compensation. The experimental results show that high precision control can be accomplished in the presence of large friction torque and very low velocities. Related Articles | Metrics | Comments（0）

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Natural Polemap Dased Localization for Intelligent Vehicles WU Shun-xi, YANG Ming Journal of Shanghai Jiaotong University    Abstract （5771）            Knowledge map    Save In order to overcome the big workload and low accuracy of measuring the polemap manually in outdoor environment, a laser radar based mapping method was presented. On the basis of this, a polemap based localization was introduced which does mapmatching using iterative closest points and can enhance the accuracy of localization. This method was tested on both synthetic and real range data collected in natural environment. The experimental results demonstrate its high accuracy, low computation and wide applicability. Related Articles | Metrics | Comments（0）

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Research and Application of Sparse Algorithm of Boundary Element Matrix CUI Shu-biao, ZHANG Yun, ZHOU Hua-min, LI De-qun Journal of Shanghai Jiaotong University    Abstract （5767）            Knowledge map    Save A method was brought forward to make the matrix become sparser because the memory space of the boundary element matrix is in direct proportion to the square of mesh number. An appropriate rule of sparsity is defined according to the characteristic of boundary element matrix at first. The matrix coefficients which are less than certain limit value are united into the adjacent elements. Afterward the matrix coefficient was evaluated as zero. And the matrix coefficient of partial adjacent elements can be incorporated into certain element by using this method. Then the boundary element matrix becomes a sparse one. By using this method, the memory space is reduced observably while guaranteeing the numerical simulation accuracy through numerical simulation. Related Articles | Metrics | Comments（0）

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A Low Complexity Maximum Weighted Sumrate Based Scheduling Algorithm in Multiuser MIMO System CHEN Lei, SHE Feng, LUO Han-wen Journal of Shanghai Jiaotong University    Abstract （5749）            Knowledge map    Save To solve the problem that the dirtypaper coding based iterative waterfilling algorithm to maximize weighted sumrate has high complexity in multiuser multiinput multioutput (MIMO) system, a low complexity zeroforcing dirtypaper coding based multiuser resource scheduling algorithm was proposed. Under the transmit power constraint, the proposed algorithm combines power allocation and user scheduling. Users are selected in sequence based on the userselection parameters which are constructed using the channel state information. The proposed algorithm only needs finite repetitions, and can drop off those users with poor channel quality through the userrejection criteria. Therefore the complexity is reduced. The simulation results show that, compared to the iterative waterfilling algorithm, the proposed algorithm achieves more than 90% weighted sumrate of the iterative waterfilling algorithm under similar simulation conditions. With the increasing user number the weighted sumrate of the proposed algorithm approximates to that of the iterative waterfilling algorithm. And the complexity is reduced from the one in proportion to the square of number of users to the one in proportion to the number of users. Related Articles | Metrics | Comments（0）