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Motor Fault Diagnosis Based on Short-time Fourier Transform and Convolutional Neural Network

Chinese Journal of Mechanical Engineering 2017年第6期30卷 1357-1368页

作者： Li-hua Wang xiao-Ping Zhao Jia-Xin Wu yang-yang Xie Yong-Hong Zhang School of Information and Control Nanjing University ofInformation Science and Technology Nanjing 210044 China School of Computer and Software Nanjing University ofInformation Science and Technology Nanjing 210044 China Network Monitoring Center of Jiangsu Province NanjingUniversity of Information Science and TechnologyNanjing 210044 China

With the rapid development of mechanical equipment, the mechanical health monitoring field has entered the era of big data. However, the method of manual feature extraction has the disadvantages of low efficiency and poor accuracy, when handling big data. In this study, the research object was the asynchronous motor in the drivetrain diagnostics simulator system. The vibration signals of different fault motors were collected. The raw signal was pretreated using short time Fourier transform （STFT） to obtain the corresponding time-frequency map. Then, the feature of the time-frequency map was adap- tively extracted by using a convolutional neural network （CNN）. The effects of the pretreatment method, and the hyper parameters of network diagnostic accuracy, were investigated experimentally. The experimental results showed that the influence of the preprocessing method is small, and that the batch-size is the main factor affecting accuracy and training efficiency. By investigating feature visualization, it was shown that, in the case of big data, the extracted CNN features can represent complex mapping relationships between signal and health status, and can also overcome the prior knowledge and engineering experience requirement for feature extraction, which is used by tra- ditional diagnosis methods. This paper proposes a new method, based on STFT and CNN, which can complete motor fault diagnosis tasks more intelligently and accurately.

关键词： Big data Deep learning Short-time Fouriertransform Convolutional neural network Motor

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FRACTAL ANALYSIS APPLIED TO SPATIAL STRUCTURE OF CHINA'S VEGETATION

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Chinese Geographical Science 2006年第1期16卷 48-55页

作者： ZHU xiao-hua Patel NILANCHAL ZUO Wei yang Xiu-chun Institute of Geographical Sciences and Natured Resou rces Research Chinese Academy of Sciences Beijing 100101 P. R. China Department of Remote Sensing Birla Institute of Technology Ranchi 835215 India Sinomaps Press Beijing 100054 P. R. China Institute of Agricultural Resources and Regional Plaaning Chinese Academy of Agricultural Sciences Beijing 100081 P. R. China

Based on the fractal theory, the spatial structure of China＇s vegetation has been analyzed quantitatively in this paper. Some conclusions are drawn as the following. 1） The relationships between size and frequency of patch area and patch shape index exist objectively for China＇s vegetation. 2） The relationships between perimeter and area exist objectively for China＇s vegetation. 3） The fractal dimension of evergreen needleleaf forests on mountains in subtropical and tropical zones is the largest, while the smallest for deciduous broadleafand evergreen needleleaf mixed forests in temperate zone, reflecting the most complex spatial structure for evergreen needleleaf forests on mountains in subtropical and tropical zones and the simplest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone. 4） The fractal dimensions of China＇s vegetation types tend to decrease from thc subtropics to both sides. 5） The stability of spatial structure of deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone is the largest, while the smallest for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards, reflecting the steadiest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone and the most unstable for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards in spatial structure. 6） The stability of spatial structure of China＇s vegetation tends to decrease from the temperate zone to both sides, it is significantly pertinent to understand the formation, evolution, dynamics and complexity rule of ecosystem of vegetation.

关键词： vegetation spatial structure fractal fractal dimension China

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EXPERIMENTAL INVESTIGATION OF EFFECTS OF INNER-TANK SLO-SHING ON HYDRODYNAMICS OF AN FLNG SYSTEM

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Journal of Hydrodynamics 2012年第1期24卷 107-115页

作者： ZHAO Wen-hua yang Jian-min HU Zhi-qiang xiao Long-fei State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The present research focuses on experimentally clarifying the effect of inner-tank sloshing on the hydrodynamics of an Floating Liquefied Natural Gas（FLNG）*** the comparisons of the results obtained from the model tests carried out with the vessel model ballasted with liquid and solid cargo separately,the effects of the inner-tank sloshing on the hydrodynamics of an FLNG system are highlighted and *** languages of the maximum,minimum,mean values and the standard deviations and power density spectra calculated with the help of the algorithm of Fast Fourier Transformation（FFT）are *** is concluded that the effects of the inner-tank sloshing on the responses of the FLNG system are sensitive to wave excitation frequencies,and that the effects of the inner-tank sloshing play an important role,particularly in the roll motion of the FLNG *** outcome of the proposed technique would offer constructive feedback,which can lead to more practical applications and can serve as a reference for the verification of the potential numerical simulations by other researchers.

关键词： Floating Liquefied Natural Gas(FLNG) hydrodynamics sloshing model tests coupled effects

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What is the cause of the neck hematoma? A rare complication of percutaneous coronary intervention of acute coronary syndrome: a case report

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Journal of Geriatric Cardiology 2020年第5期17卷 300-302页

作者： hua WANG Zhao-Jun XU xiao-yang ZHOU HwaMei Hospital University of Chinese Academy of SciencesNingboChina

As the"gold standard"for diagnosis and treatment of coronary heart disease,percutaneous coronary intervention(PCI)has become one of the most common interventional methods in clinical *** the cardiac complication,one of the most frequent complications is post PCI *** was found that the median bleeding rates in various hospitals varied between approximately 2%and 10%between hospitals in the 5th and 95th percentile.

关键词： Bleeding Percutaneous coronary intervention Neck hematoma

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A Unified Measurement Solution of Software Trustworthiness Based on Social-to-Software Framework

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Journal of Computer Science & Technology 2018年第3期33卷 603-620页

作者： Xi yang Gul Jabeen Ping Luo xiao-Ling Zhu Mei-hua Liu Key Laboratory for Information System Security School of Software Tsinghua University Beijing 100084 China School of Computer and Information Hefei University of Technology Hefei 230009 China Department of Foreign Languages and Literatures Tsinghua University Beijing 100084 China

As trust becomes increasingly important in software domain, software trustworthiness--as a complex high- composite concept, has developed into a big challenge people have to face, especially in the current open, dynamic and ever-changing Internet environment. Furthermore, how to recognize and define trust problem from its nature and how to measure software trustworthiness correctly and effectively play a key role in improving users＇ trust in choosing software. Based on trust theory in the field of humanities and sociology, this paper proposes a measurable S2S （Social-to-Software） software trustworthiness framework, introduces a generalized indicator loss to unify three parts of trustworthiness result, and presents a whole metric solution for software trustworthiness, including the advanced J-M model based on power function and time-loss rate for ability trustworthiness measurement, the fuzzy comprehensive evaluation advanced-model considering effect of multiple short boards for basic standard trustworthiness, and the identity trustworthiness measurement method based on the code homology detecting tools. Finally, it provides a case study to verify that the solution is applicable and effective.

关键词： software trustworthiness measurement solution loss social-to-software(S2S)framework generalized indicator

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小细胞性肺癌患者检测抗纺锤体抗体和抗着丝点抗体的临床意义

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中国免疫学杂志 2017年第3期33卷 418-421页

作者：谭立明张玉红陈娟娟李华肖扬婧卿吴洋曾婷婷田永建余建林南昌大学第二附属医院检验科南昌330006 南昌大学医学院南昌330006

目的:研究抗纺锤体(MSA)和抗着丝点(ACA)抗体检测对诊断小细胞性肺癌(SCLC)的临床价值,为SCLC的分子研究提供临床依据。方法:对93例SCLC患者和208例非小细胞性肺癌(NO-SCLC)患者及50例健康体检者,用酶联免疫法定量检测MSA抗体,间接免疫... 详细信息

目的:研究抗纺锤体(MSA)和抗着丝点(ACA)抗体检测对诊断小细胞性肺癌(SCLC)的临床价值,为SCLC的分子研究提供临床依据。方法:对93例SCLC患者和208例非小细胞性肺癌(NO-SCLC)患者及50例健康体检者,用酶联免疫法定量检测MSA抗体,间接免疫荧光法定性检测MSA、ACA和抗核抗体(ANA),并对其结果进行回顾性分析。结果:1IIF法检测SCLC组MSA和ACA阳性率为36.56%和30.11%,均高于其他肿瘤组(P<0.01)。2相关性分析,MSA与SCLC的RR值高达12.93、12.74,ACA和ANA与SCLC的RR值为4.31和3.48。3MSA检测SCLC的ROC曲线下面积AUC为0.778,诊断价值中等。结论:MSA和ACA对SCLC有很强正相关危险因素,可能参与SCLC的发生发展,对SCLC的早期检测、临床诊断及潜在的治疗方法有一定的应用价值。

关键词：小细胞型肺癌抗纺锤体抗体抗着丝点抗体抗核抗体

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Optimal design of Stewart platforms based on expanding the control bandwidth while considering the hydraulic system design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 22-30页

作者： Wei WANG hua-yong yang Jun ZOU xiao-dong RUAN Xin FU State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart *** method is based on generalized natural frequency and takes hydraulic oil into consideration.A Lagrangian formulation which considers the whole leg inertia is presented to obtain the accurate equivalent mass *** the model,the effect of leg inertia and the influence of design parameters on the generalized natural frequency are ***,numerical examples are presented to validate and confirm the efficiency of the mathematical *** results show that the leg inertia,especially the piston part plays an important role in the *** optimum diameter ratio of the base to the moving platform is between 2 and 3,and the optimum joint angle ratio of the base to the moving platform is about *** smaller joint angles and a longer leg stroke are favorable for raising system *** system oil should be preprocessed for large platforms with a requirement for good dynamic performance.

关键词： Large Gough-Stewart platform Optimal design Control bandwidth Leg inertia Generalized natural frequency

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Anxiety and depression in patients with gastroesophageal reflux disease and their effect on quality of life

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World Journal of Gastroenterology 2015年第14期21卷 4302-4309页

作者： xiao-Jun yang Hong-Mei Jiang xiao-hua Hou Jun Song Division of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and Technology Department of Gastroenterology Chongqing Hospital of Traditional Chinese Medicine

AIM: To explore the role of psychological factors in gastroesophageal reflux disease(GERD) and their effect on quality of life(Qo L) of GERD ***: A total of 279 consecutive patients with typical symptoms and 100 healthy controls were enrolled in the *** of the participants wereevaluated with the Zung Self-Rating Anxiety Scale(ZSAS), the Zung Self-Rating Depression Scale(ZSDS) and the SF-36 *** scores for anxiety, depression and Qo L of the two groups were *** correlation between psychological factors and Qo L was also ***: Compared with healthy controls(34.70 ± 8.00), the scores of ZSAS in the non-erosive reflux disease( N E R D) group(48.27±10.34) and the reflux esophagitis(RE) group(45.38 ± 10.27) were significantly higher(P < 0.001).The mean ZSAS score of the NERD group was significantly higher than that of the RE group(P = 0.01).Compared with healthy controls(37.61 ± 8.44), the mean ZSDS scores were significantly higher in the NERD group(49.65 ± 11.09, P < 0.001) and the RE group(46.76 ± 11.83, P < 0.001).All dimensions of the SF-36 form were negatively correlated with the SAS and SDS scores in patients with NERD and RE(P < 0.05).According to the S F- 3 6 form, vitality, mentalhealth and social functioning were significantly correlated with symptoms of depression in patients with NERD and *** health was obviously affected by symptoms of depression in patients with NERD(P < 0.05).CONCLUSION: Anxiety and depression may play an important role in the occurrence of GERD and especially that of *** Qo L of patients with GERD is reduced by anxiety and depression.

关键词： Anxiety Depression Gastroesophageal reflux disease

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Recent advances in asymmetric synthesis of 2-substituted indoline derivatives

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Chinese Chemical Letters 2020年第2期31卷 311-323页

作者： Ting-Bi hua Cong xiao Qing-Qing yang Jia-Rong Chen College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology Ministry of Education.College of ChemistryCentral China Normal UniversityWuhan 430079China

Enantiomerically pure 2-substituted indolines are an important class of nitrogen heterocycles that occur frequently in many alkaloid natural products and biologically active ***,the synthesis of such skeletons is of great *** past years have witnessed a number of remarkable advances in the development of efficient strategies to construct this class of chiral *** review summarizes the recent advances in asymmetric synthesis of 2-substituted indoline *** to the limitation of the length,this review only summarizes those works published from January of 2012 to January of ***,methods towards synthesis of fu sed and spirocyclic indolines will not be discussed in this review.

关键词： Indolines Asymmetric synthesis Enantioselectivity Nitrogen heterocycles Synthetic methods

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Assessment of the Sensitivity and Specificity of the Established Real-time Quaking-induced Conversion(RT-QuIC)Technique in Chinese CJD Surveillance

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Biomedical and Environmental Sciences 2020年第8期33卷 620-622页

作者： xiao Kang yang Xue hua ZOU Wen Quan DONG xiao Ping SHI Qi State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases(Zhejiang University)National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Center for Global Public Health Chinese Center for Disease Control and PreventionBeijing 102206China Wuhan Institute of Virology Chinese Academy of ScienceWuhan 430071Hubei China

Real-time quaking-induced conversion(RT-QuIC)assay is a newly established PrPSc-detecting *** development of RT-QuIC improves the diagnosis of sporadic Creutzfeldt–Jakob disease(sCJD),showing good sensitivity and specificity in many countries when the method was used in cerebrospinal fluid(CSF)***,in China,the sensitivity and specificity of RT-QuIC has yet to be determined due to the lack of definitive diagnosis samples.

关键词： diagnosis CJD cerebrospinal

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