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Support Vector Regression Based Color Image Restoration in YUV Color Space

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Journal of shanghai jiaotong university(science) 2010年第1期15卷 31-35页

作者：黎明杨杰苏中义 Institute of Image Processing and Pattern Recognition Shanghai Jiaotong University Department of Electronic engineering Shanghai Dianji University

A support vector regression(SVR) based color image restoration algorithm is *** test color images are firstly mapped into the YUV color space,and then SVR is applied to build up a theoretical model between the degraded images and the original *** comparisons of the proposed algorithm versus traditional filtering algorithms are *** results show that the proposed algorithm has better performance than traditional filtering algorithms and has less computation time than iterative blind deconvolution algorithm.

关键词： color image restoration support vector regression (SVR) color space

ROBUST OPTIMIZATION OF TRANSMIT/RECEIVE BEAMFORMER FOR MIMO DOWNLINK WITH IMPERFECT CSI AT BASE STATION

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Journal of Electronics(china) 2008年第5期25卷 601-606页

作者： Li Hao Xu Changqing Dept. of Electronic engineering Shanghai Jiaotong University Shanghai 200240 China

A robust scheme is proposed to jointly optimize transmit/receive beamformers for Mul-tiple Input Multiple Output(MIMO) downlinks where the available Channel State Information(CSI) at Base Station(BS)(CSIBS) is *** criterion is to minimize the sum Mean Square Error(sum-MSE) over all users under a constraint on the total transmit power,which is a non-convex and non-linear *** from the first order optimization condition that the optimal trans-mit/receive beamformers are mutually dependent,the transmit/receive beamformers for each user are updated iteratively until the sum-MSE is *** results indicate that the proposed scheme can effectively mitigate the system performance loss induced by imperfect CSIBS.

关键词： Multiple Input Multiple Output (MIMO) downlink Transmit/receive beamformer Imperfect Channel State Information (CSI)

Nonlinear Free Vibration Analysis of Thin-walled Curved Beam with Non-symmetric Open Cross Section

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Journal of shanghai jiaotong university(science) 2008年第2期13卷 150-154页

作者：段海娟宋振森 Department of Civil engineering Shanghai Jiaotong University

A finite element formulation was presented for the nonlinear free vibration of thin-walled curved beams with non-symmetric open across section. The kinetic and potential energies were derived by the virtual principle. The energy function includes the effect of fiexural-torsional coupling, the torsion warping and the shear centre location. For finite element analysis, cubic polynomials were utilized as the shape functions of the two nodal thin-walled curved elements. Each node possesses seven degrees freedom including the warping degree of freedom. The nonlinear eigenvalue problem was solved by the direct iteration technique. The results are compared with those for straight beams as available in the literature. The results for nonlinear free vibration analysis of curved beams for various radii and subtended angle are presented.

关键词： nonlinear vibration thin-walled curved beam finite element method virtual principle

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污水厂头孢类抗生素去除规律及潜在风险评估

上海交通大学学报 2010年第11期44卷 1550-1555页

作者：王朋华袁涛上海交通大学环境科学与工程学院上海200240

利用固相萃取-高效液相色谱-紫外检测（SPE-HPLC-UVD）分析方法,研究了不同季节5种头孢类抗生素在上海市两污水厂（MH和XZ污水厂）进水及出水中的含量水平及去除规律,并初步评价了其对受纳水体的潜在风险.结果显示,5种头孢类抗生素在污... 详细信息

利用固相萃取-高效液相色谱-紫外检测（SPE-HPLC-UVD）分析方法,研究了不同季节5种头孢类抗生素在上海市两污水厂（MH和XZ污水厂）进水及出水中的含量水平及去除规律,并初步评价了其对受纳水体的潜在风险.结果显示,5种头孢类抗生素在污水厂进水（出水）中检出浓度（均值）为1.12-2.75μg/L（0.01-1.32μg/L）.综合MH污水厂的季节采样分析,发现7月份的检测浓度均低于其他3个月份,这可能与头孢类抗生素使用量的季节波动和温度升高促进其降解有关.比较分析两污水厂数据,结果提示氧化沟工艺对头孢类抗生素的去除效果比A^2/O工艺好.另外,出水中的日流量计算结果表明,在不同时期,不同头孢类抗生素的排放负荷不同,对受纳水体的影响也不同.

关键词：污水头孢类抗生素含量水平去除潜在风险

Towards On-line Automated Semantic Scoring of English-Chinese Translation

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Journal of shanghai jiaotong university(science) 2007年第6期12卷 725-730页

作者：田艳陆汝占吴宝松 Dept.of computer science and Eng.shanghai jiaotong Univ.Dept.of computer science and Eng.shanghai jiaotong Univ.shanghai 200240 china Language Testing and Evaluation Center shanghai jiaotong Univ.shanghai 200240 china

Described and exemplified a semantic scoring system of students' on-line English-Chinese translation. To achieve accurate assessment, the system adopted a comprehensive method which combines semantic scoring with keyword matching scoring. Four kinds of words-verbs, adjectives, adverbs and "the rest" including nouns, pronouns, idioms, prepositions, etc., are identified after parsing. The system treats different words tagged with different part of speech differently. Then it calculated the semantic similarity between these words of the standard versions and those of students' translations by the distinctive differences of the semantic features of these words with the aid of HowNet. The first semantic feature of verbs and the last semantic features of adjectives and adverbs are calculated. "The rest" is scored by keyword matching. The experiment results show that the semantic scoring system is applicable in fulfilling the task of scoring students' on-line English-Chinese translations.

关键词： English-Chinese translation automated natural language processing on-line semantic scoring

Pulsation Characteristics of Ventilated Supercavitation on a 2D Hydrofoil

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Journal of shanghai jiaotong university(science) 2010年第4期15卷 423-427页

作者：郭建红鲁伟敬 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

Based on a suite of computational fluid dynamics code, the pulsation characteristics are studied for turbulent supercavitating flows over a 2D base-vented symmetric hydrofoil using a pressure-based Navier-Stokes solver coupled with a phase mass fraction transport cavitation model and local linear low-Reynolds-number k-ε turbulence model. It is found that there exists a critical air supply flow under certain inflow condition. When the gas supply flow exceeds the critical value, the cavity begins to pulsate. Pulsating cavity has a visually wavy surface, and air leakage shows as a mass of air-water mixture detaching from the rear part of the cavity periodically.

关键词： numerical simulation ventilated cavity pulsating cavity multiphase flow

Improvement of Collaborative Optimization

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Journal of shanghai jiaotong university(science) 2010年第2期15卷 172-177页

作者：黄海燕王德禹 School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University

This paper presents a new improved collaborative optimization (CO) model that provides solution capabilities for multiobjective multidisciplinary optimization problems. Reasons that cause computational difficulties in CO algorithm are firstly analyzed. Then a new system level objective function is advised to minimize relative value between the collaborative objective function and single disciplinary objective function. And it eliminates the effect of dimensions and magnitude orders among objectives. A new subsystem level objective function is developed that includes the disciplinary objective function and the consistency constraint. A new CO framework which is more suitable for multilevel distributed design is advised. In this CO framework,the system level optimizer does not only independently invoke the subdisciplinary analysis tools,but also invoke its subdiscipline optimizer. The improved CO model proposed in this work is demonstrated with two examples. The results of examples show the improved CO is not only feasible,reliable and efficient,but also well suitable to solve the multiobjective optimization problems in multidisciplinary design environment.

关键词： multidisciplinary design optimization collaborative optimization (CO) multiobjective improvement

RESONANCE RADIATION OF SUBMERGED INFINITE CYLINDRICAL SHELL

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Chinese Journal of Mechanical engineering 2002年第2期15卷 116-120页

作者： LiuTao Wan Lin Tang Weilin Fan JunState Key Laboratory of Vibration, Shock & Noise, shanghai jiaotong university,shanghai 200030, china shanghai jiaotong university State Key Laboratory of Vibration Shock & Noise 上海 200030

The resonance sound radiation from submerged infinite elastic cylindricalshell, excited by internal harmonic line force, is investigated. The shell radiation power ispresented in terms of resonant modal radiation derived from resonance radiation theory (RRT). Theresonance radiation formulae are derived from classical Rayleigh normal mode solution, which areuseful for understanding the mechanism of sound radiation from submerged shells. As an example,numerical calculation of a thin steel cylindrical shell is done by using these two methods. It seemsthat the results of RRT solutions are in good agreement with that of Rayleigh normal modesolutions.

关键词： Cylindrical shell Sound and vibration Resonance radiation

Flow Control Strategy for the High Speed Network Based on Control Theory

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Journal of Systems engineering and Electronics 2002年第2期13卷 45-49页

作者： Sun Peng, Zhang Haoran & Han ZhengzhiDept. of Automation, Intelligent engineering Laboratory, shanghai jiaotong university, shanghai 200030, P.R.china(Received July 9, 2001) Dept. of Automation Intelligent Engineering Laboratory Shanghai Jiaotong University Shanghai 200030 P. R. China

Design of an effective congestion control scheme is a hot topic in the development of compute network. The flow control scheme can adjust the packet sending rate in source host, thus effectively avoiding the network congestion. This paper proposes a flow control scheme based on discrete control theory. The simulation results show that this method can adjust the sending rate and queue level in buffer rapidly and effectively. The method is easy to implement and applicable to high speed networks.

关键词： Algorithms Buffer storage Congestion control (communication) Packet switching