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A new current sensor incipient fault diagnosis method for converters in wind energy conversion systems

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Science China(Information Sciences) 2022年第5期65卷 276-277页

作者： Songbing TAO Youqiang HU Shuiqing XU yi CHAI ke ZHANG College of Automation Chongqing University College of Electrical Engineering and Automation Hefei University of Technology

Dear editor,The efficient and clean characteristics of wind energy have led to the development of wind power generation as one of the most sophisticated ways of power generation [1]. To guarantee the reliability and safety of the energy conversion process, current sensors have played a significant role in the wind energy conversion systems (WECSs). However, to the best of the author’s knowledge, the literature concerning current sensor fault diagnosis is limited.

关键词： Incipient fault Current sensor Fault diagnosis Wind power Instantaneous amplitude Fault location

Partial Regularity of Suitable Weak Solutions of the Model Arising in Amorphous Molecular Beam Epitaxy

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2219-2246页

作者： Yan Qing WANG yi ke HUANG Gang WU Dao Guo ZHOU College of Mathematics and Information Science Zhengzhou University of Light IndustryZhengzhou 450002P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

In this paper,we are concerned with the precise relationship between the Hausdorff dimension of possible singular point set S of suitable weak solutions and the parameterαin the nonlinear term in the following parabo... 详细信息

关键词： Surface growth model modified Navier–Stokes equations partial regularity Hausdorff dimension

Sequential Experiment Design Method Based on Uniformity and Distortion of Responses

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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 778-790页

作者： Qian-yi HUANG Liang-wei QI Jing-ke ZHANG Yu TANG State key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System(CEMEE) Luoyang 471003China School of Mathematical Sciences Soochow UniversitySuzhou 215006China

With the development of modern electronic countermeasure technology,the fight between radar jamming and anti-jamming in aviation military has become increasingly *** are some special requirements for radar countermeasure *** example,such experiments are often divided into several stages,and responses of the previous stages will become factors of the next ***,the experiment design can only consider some typical level values of the ***,the experiment factors are mostly continuous *** when there are some jumps in the response,and the value granularity of the factor level is large,the responses fail to reflect the distortion process,which makes it difficult to explore the radar performance ***,it is necessary to study the sequential experiment design method with the optimization goals of response uniformization and response distortion process *** this paper,a sequential experiment design strategy based on Kriging model is ***,Kriging model is used to fit the initial experimental data to obtain the response *** order to enhance the uniformity of response distribution,Shannon entropy is applied to the objective function as the measure of *** for the situation of response distortion,we consider replacing the existing experiment points with those whose corresponding responses have a larger gradient *** means that the response value near these points will change rapidly,so they are more valuable for *** we use the peak surface in the three-dimensional space to intuitively verify the effect of the above algorithms on response uniformization and response distortion process characterization,and use the simulated annealing algorithm to solve *** simulation results show that our sequential experiment strategy has a good ***,we apply the strategy to the practical problem of radar countermeasure experiment,and the obtained results

关键词： radar countermeasure experiments response distortion sequential experiment uniform distribution

A novel laminated metal composite with superior interfacial bonding composed of ultrahigh strength maraging steel and 316L stainless steel

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Journal of Iron and Steel Research International 2020年第4期27卷 433-439页

作者： Le Zhang Wei Wang M.Babar Shahzad yi-yin Shan ke Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026AnhuiChina key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina

A 5-layer laminated metal composite composed of ultrahigh-strength maraging steel and ductile 316L stainless steel was fabricated by hot pressing in vacuum and post-heat *** characterization on hierarchical structure of the composite before and after heat treatment was made by optical microscopy,scanning electron microscopy and electron back-scattered diffraction technique,***,the difference of mechanical performance on both sides of the interface was characterized by nano-hardness *** tensile test showed that superior interfacial bonding was achieved due to the micro-‘bite’structure between the two steels without obvious defects or oxides at the interface and with coordinated deformation of the two ***,a laminated metal composite consisting of two different constituents with extreme difference in strength can be well fabricated.

关键词： Maraging steel Austenitic stainless steel Laminated metal composite Hierarchical structure Interfacial

A novel and convenient synthesis of thiazolo[3,2-a]pyrimidin-7-ones and pyrido[1,2-a]pyrimidin-2-ones using Vilsmeier reagent

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Chinese Chemical Letters 2012年第8期23卷 911-914页

作者： yi yi Weng Lei Ming ying Qi Xu Chen Wei ke Su key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education College of Pharmaceutical SciencesZhejiang University of TechnologyHangzhou 310014China

A novel route for the synthesis of thiazolo[3,2-a]pyrimidin-7-ones and pyrido[1,2-a]pyrimidin-2,ones from acetylated 2- aminothiazoles and 2-aminopyridines under Vilsmeier conditions has been developed. The plausible ... 详细信息

关键词： Thiazolo[3,2-a]pyrimidin-7-ones Pyrido[1,2-a]pyrimidin-2-ones Bis-(trichloromethyl) carbonate Vilsmeier-Haack reaction

Has the Prediction of the South China Sea Summer Monsoon Improved Since the Late 1970s?

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Journal of Meteorological Research 2016年第6期30卷 833-852页

作者： FAN yi FAN ke1 TIAN Baoqiang Nansen–Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology

Based on the evaluation of state-of-the-art coupled ocean-atmosphere general circulation models （CGCMs） from the ENSEMBLES （Ensemble-based Predictions of Climate Changes and Their Impacts） and DEME- TER （Development of a European Multimodel Ensemble System for Seasonal to Interannual Prediction） projects, it is found that the prediction of the South China Sea summer monsoon （SCSSM） has improved since the late 1970s. These CGCMs show better skills in prediction of the atmospheric circulation and precipitation within the SCSSM domain during 1979-2005 than that during 1960-1978. Possible reasons for this improvement are investigated. First, the relationship between the SSTs over the tropical Pacific, North Pacific and tropical Indian Ocean, and SCSSM has intensified since the late 1970s. Meanwhile, the SCSSM-related SSTs, with their larger amplitude of interannual variability, have been better predicted. Moreover, the larger amplitude of the interannual variability of the SCSSM and improved initializations for CGCMs after the late 1970s contribute to the better prediction of the SCSSM. In addition, considering that the CGCMs have certain limitations in SCSSM rainfall prediction, we applied the year-to-year increment approach to these CGCMs from the DEMETER and ENSEMBLES projects to improve the prediction of SCSSM rainfall before and after the late 1970s.

关键词： South China Sea summer monsoon prediction Ensemble-based Predictions of Climate Chan-ges and Their Impacts Development of a European Multimodel Ensemble System for Seasonalto Interannual Prediction year-to-year increment prediction approach

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基于自研光谱仪的痕量气体光解速率测量研究

光谱学与光谱分析 2025年第1期45卷 15-23页

作者：李浩然曾议朱磊窦科刘志宏常振江宇司福祺中国科学院合肥物质科学研究院安徽光学精密机械研究所环境科学与技术重点实验室安徽合肥230031 中国科学技术大学科学岛分院安徽合肥230026 合肥大学生物食品与环境学院安徽合肥230601

光解速率及其测量技术最早由德国科学家提出,21世纪初Metcon公司开发了光解速率测量仪,该技术在国内得到关注,部分高校和公司对光解速率测量系统开展了研究和开发。国外产品一般体积较大,价格昂贵。国内产品中光谱仪、接收器等核心器件... 详细信息

光解速率及其测量技术最早由德国科学家提出,21世纪初Metcon公司开发了光解速率测量仪,该技术在国内得到关注,部分高校和公司对光解速率测量系统开展了研究和开发。国外产品一般体积较大,价格昂贵。国内产品中光谱仪、接收器等核心器件仍依赖于国外进口,易受国外技术封锁影响。在我国“十四五”国家重点研发计划中“大气与土壤、地下水污染综合治理”重点专项对化学气候综合站检测技术与装备需求引导下,研制了测量大气物质光解速率的光谱仪系统,并满足其核心部件国产化的要求。系统采用自主设计的小型光谱仪作为核心部件,配合各向均匀响应的光学接收器,经实验室光学定标后测得各种物质的光解速率。该系统工作波段为285~430 nm,时间分辨率可达0.1 s,可测物质包括NO_(2)、HONO、HCHO、H_(2)O_(2)等,与国外进口测量仪器对比,各气体物质光解速率的测量误差小于5%,相关性均超过0.93。采用该系统在合肥市董铺岛对大气中气体光解速率开展了长时间的连续监测。对NO_(2)光解速率变化趋势以及NO_(2)光解速率与浓度间的相关性进行分析,发现光解反应与驱动光化反应的能量密切相关,晴天的光解速率数值明显高于阴天与雨天。发现NO_(2)光解速率与浓度的积分曲线间存在一种经验公式,相关性大于0.9,可通过测量NO_(2)光解速率对NO_(2)浓度的累积量进行估计。该系统实现了核心部件的国产化,整体结构简单、便携,方便外场试验安装的同时,降低成本,提高经济性。研究为大气污染综合监测治理提供数据支撑,对各地区的环境监测及污染预防具有参考意义。

关键词：光解速率光谱仪辐亮度光学接收器

A Content-Based Parallel Image Retrieval System on Cluster Architectures

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Wuhan University Journal of Natural Sciences 2004年第5期9卷 665-670页

作者： ZHOUBing SHENJun-yi PENGQin-ke SchoolofElectronicsandInformationEngineering Xi＇anJiaotongUniversityXi＇an710019ShaanxiChina

We propose a content-based parallel image retrieval system to achieve high responding ability. Our system is developed on cluster architectures. It has several retrieval. servers to supply the service of content-based image retrieval. It adopts the Browser/Server (B/S) mode. The users could visit our system though web pages. It uses the symmetrical color-spatial features (SCSF) to represent the content of an image. The SCSF is effective and efficient for image matching because it is independent of image distortion such as rotation and flip as well as it increases the matching accuracy. The SCSF was organized by M-tree, which could speedup the searching procedure. Our experiments show that the image matching is quickly and efficiently with the use of SCSF. And with the support of several retrieval servers, the system could respond to many users at mean time. key words content-based image retrieval - cluster architecture - color-spatial feature - B/S mode - task parallel - WWW - Internet CLC number TP391 Foundation item: Supported by the National Natural Science Foundation of China (60173058)Biography: ZHOU Bing (1975-), male, Ph. D candidate, reseach direction: data mining, content-based image retrieval.

关键词： content-based image retrieval cluster architecture color-spatial feature B/S mode task parallel WWW Internet

Si-Nanocrystals with Bimodal Size Distribution in Evenly Annealed SiO Revealed with Raman Scattering

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Chinese Physics Letters 2012年第1期29卷 202-205页

作者： ke Wei-Wei FENG Xue HUANG yi-Dong State key Laboratory of Integrated Optoelectronics Department of Electronic EngineeringTsinghua UniversityBeijing 100084

The size distribution of Si-nanocrystals(Si-ncs)in evenly annealed SiO is investigated with transmission electron microscopy(TEM),x-ray diffraction(XRD),and Raman *** groups of Si-ncs with very different most probable diameters are identified,where one is>6nm and the other one is10nm)and it can be revealed clearly for all samples by Raman spectra with two components(~500cm^(-1)and~520cm^(-1)).The results of XRD show the average *** experimental results indicate that the common assumption of Si-nc size distribution with single most probable diameter is not always proper and the possible mechanisms are briefly discussed.

关键词： temperature. scattering. effect.