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Study of the ionospheric anomaly before the Wenchuan earthquake

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Chinese Science Bulletin 2009年第4期54卷 1080-1086页

作者： YU Tao mao Tian WANG YunGang WANG JingSong Nation Center for Space Weather China Meteroligical Administration Beijing 100081 China

The behavior of the ionosphere before the Wenchuan earthquake is analyzed with the global TEC and ionospheric foF2 observed at Xiamen. It can be found from TEC maps that in the afternoon (16―18LT) on May 9, 2008, 3 days before the earthquake, there is an enhancement of TEC with an amplitude of 10―15 TECU appearing in the east-south direction of Wenchuan, and another enhancement appears at the conjugate region of the Southern Hemisphere with an amplitude of 10 TECU, but no obvious in-crement or decrement can be seen in other regions on global scale. It can also be found that on May 6 (6 days before the great earthquake), there is a decrement of TEC with small amplitude of 4TECU and larger area with 80° along the longitude in southern China, and there is no synchronous decrement observed at the conjugate region of the Southern Hemisphere. There are also many anomalies ob-served by ionosondes across China. The result shows that foF2 and TEC abnormally increased, which is different from pervious results that ionospheric parameters decreased prior to earthquakes. Pre-liminary results suggest that the enhancement on May 9 maybe has a close relationship with the pos-sible enhancement of ionospheric electric fields, and it may be an ionospheric precursor of earth-quakes. Whereas the decrement on May 6 may be attributed to the geomagnetic disturbance appearing on May 5.

关键词：电离层异常地震前汶川电离层参数地球电离层地磁场扰动华南地区 TEC

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A RANDOMIZED TRIAL OF ELECTROACUPUNCTURE FOR FATIGUE, SLEEP, AND PSYCHOLOGICAL DISTRESS IN BREAST CANCER PATIENTS WITH AROMATASE INHIBITOR-RELATED ARTHRALGIA

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Journal of Integrative Medicine 2014年第3期 296-297页

作者： Jun mao Perelman School of Medicine at University of Pennsylvania

Background: While fatigue, sleep disturbance, depression and anxiety are associated with pain in breast cancer patients, it is unknown if acupuncture can decrease these co-morbid symptoms in cancer patients with *** study aimed at evaluating the effects of electroacupuncture(EA) on fatigue, sleep and psychological distress in breast cancer survivors who experience joint pain related to aromatase inhibitors(AIs).Methods: We performed a randomized controlled trial of an eight-week EA as compared to waitlist control(WLC) and sham acupuncture(SA) in postmenopausal women with breast cancer who self-reported joint pain attributable to *** performed 10 EA/SA treatments over eight weeks using a manual protocol with 2 Hz electro-stimulation delivered by a TENS *** administered SA using Streitberger(nonpenetrating) needles at non-acupuncture points without ***, sleep disturbance, anxiety and depression were measured by the Brief Fatigue Inventory(BFI), Pittsburgh Sleep Quality Index(PSQI), and Hospital Anxiety and Depression Scale(HADS).The effects of EA and SA *** on these outcomes were evaluated using mixed-effects ***: Of the 67 randomly assigned patients, baseline paininterference was associated with fatigue(Pearson correlation coefficient r=0.75, P<0.001), sleep(r=0.38, P=0.002 6), and depression(r=0.58, P<0.001).Compared to the WLC, EA produced significant improvement in fatigue(P=0.009 5), anxiety(P=0.044), and depression(P=0.015) and marginal improvement in sleep(P=0.058) during the 12-week intervention and followup *** contrast, SA only produced significant improvement in depression compared with WLC(P=0.008 8).Conclusion: Among women who experienced AI-related arthralgia, EA produced significant improvement in fatigue, anxiety and depression, while SA improved only *** findings provide initial evidence to suggest that EA may reduce pain-related symptom clusters in breast can

关键词： WLC SLEEP AND PSYCHOLOGICAL DISTRESS IN BREAST CANCER PATIENTS WITH AROMATASE INHIBITOR-RELATED ARTHRALGIA SA A RANDOMIZED TRIAL OF ELECTROACUPUNCTURE FOR FATIGUE

Prediction of Pollution Flashover Voltage Based on Leakage Current Under AC Operating Voltage

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高电压技术 2012年第8期38卷 1924-1929页

作者： MEI Hongwei WANG Liming GUAN Zhicheng mao Yingke Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China Shanghai Extra High Voltage Power Transmission Company Shanghai 200063 China

This paper presented a model to predict the AC flashover voltage of contaminated suspension *** prediction method is based on the maximum leakage current under AC operating *** kinds of widely used suspension insulators were tested in various contamination states such as pollution layers with different equivalent salt deposit density(ESDD),different composition of the conductive components,different non-soluble deposit density(NSDD) and different pollution distribution states to simulate the contamination states in *** effective ESDD was proposed and *** of contamination states to maximum leakage current and flashover voltage were ***,the relationships between flashover voltage and leakage current in these states were ***,considering the difference of insulator profiles,a new parameter is defined and a model to estimate the flashover voltage based on this parameter is *** model could be used in all kinds of suspension insulators in different contamination states and was validated by the test results.

关键词：局部放电射频信号放电量高电压技术

Shanghai's New Foreign Economic and Trade Achievements in 1996

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China's Foreign Trade 1997年第4期 11-12页

作者： Jin mao

1996 was the first year of Shanghai’s Ninth Five-year Plan in foreign trade. Although the country saw significant readjustment in foreign-related economic policies and great changes in macroeconomic environment, Shanghai’s foreign economic and trade work stood the test, maintained steady growing development and realized all the goals set

关键词： over US Shanghai’s New Foreign Economic and Trade Achievements in 1996

基于双光反馈垂直腔面发射激光器获取双路高速物理随机数研究

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光电子．激光 2015年第11期26卷 2062-2069页

作者：魏丽霞唐曦吴正茂夏光琼西南大学物理科学与技术学院重庆400715

提出基于双光反馈下垂直腔面发射激光器(VCSELs)输出的正交偏振分量混沌振荡来同时获取两路物理随机数(PRN)的方案,数值分析了不同反馈强度下所获取的最终比特序列的随机性能。研究结果表明,通过选择合适的反馈参量可使VCSELs中两个偏... 详细信息

提出基于双光反馈下垂直腔面发射激光器(VCSELs)输出的正交偏振分量混沌振荡来同时获取两路物理随机数(PRN)的方案,数值分析了不同反馈强度下所获取的最终比特序列的随机性能。研究结果表明,通过选择合适的反馈参量可使VCSELs中两个偏振分量均呈现混沌振荡;其输出的两路混沌信号作为熵源,经8位模数转换器(ADC)量化、比特序列按位反转、异或(XOR)运算和m bit最低有效位(m-LSBs)截取等后续处理后可得到最终比特序列;采用美国国家标准技术研究所(NIST)提供的NIST special publication 800-22统计测试套件对基于不同反馈强度下所产生的混沌信号熵源所获取的最终比特序列的性能进行测试,初步确定了获取可通过NIST speical publication 800-22统计测试的两路随机数所需的反馈强度的范围。

关键词：垂直腔面发射激光器(VCSEL) 双光反馈混沌熵源物理随机数(PRN)

Book Review of History of Huizu in China

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Asian Journal of Middle Eastern and Islamic Studies 2007年第1期1卷 80-80,I0008页

作者： Yufeng mao ashington University in St.Louis

Shusen Qiu,et ***.,Zhongguo Huizu Shi(History of Huizu in China),2 Volumes,Yinchuan:Ningxia Renmin Chubanshe,*** product of collaboration by ten leading Chinese scholars,these two volumes represent the encyclopedic work on the history of Chinese *** to the work of authors such as Shusen Qiu,who specializes in Muslim history during the Yuan Dynasty,this work is particularly detailed in recounting the development of Muslim communities prior to the more familiar Ming-Qing and modern periods.

关键词： History Ningxia collaboration

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大时滞系统鲁棒自调节控制器

哈尔滨工业大学学报 2007年第5期39卷 716-720页

作者：张卯瑞哈尔滨工业大学航天学院哈尔滨150001

基于一阶时滞模型FOPDT(First order dynamics plus dead time)与继电器反馈构成的系统产生的极限环,提出了一种简单、精确的参数辨识方法.通过手动或智能测量设备就可以测得输出上几个点的数据,进一步可辨识出模型参数.低阶滤波器被用... 详细信息

基于一阶时滞模型FOPDT(First order dynamics plus dead time)与继电器反馈构成的系统产生的极限环,提出了一种简单、精确的参数辨识方法.通过手动或智能测量设备就可以测得输出上几个点的数据,进一步可辨识出模型参数.低阶滤波器被用来提高采用史密斯预估器控制系统的鲁棒性,简单的FOPDT模型用于具有时滞主导的高阶系统.仿真和分析表明了该自调节控制器的有效性、鲁棒性和显著的性能改进.

关键词：自调节鲁棒史密斯预估器时滞过程极限环

Structurally Flexible 2D Spacer for Suppressing the Electron-Phonon Coupling Induced Non-Radiative Decay in Perovskite Solar Cells

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Nano-Micro Letters 2024年第9期16卷 325-340页

作者： Ruikun Cao Kexuan Sun Chang Liu Yuhong mao Wei Guo Ping Ouyang Yuanyuan Meng Ruijia Tian Lisha Xie Xujie Lü Ziyi Ge Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Center for High Pressure Science and Technology Advanced Research(HPSTAR) Shanghai 201203People’s Republic of China

This study presents experimental evidence of the dependence of non-radiative recombination processes on the electron-phonon coupling of perovskite in perovskite solar cells(PSCs).Via A-site cation engineering,a weaker electron-phonon coupling in perovskite has been achieved by introducing the structurally soft cyclohexane methylamine(CMA^(+))cation,which could serve as a damper to alleviate the mechanical stress caused by lattice oscillations,compared to the rigid phenethyl methylamine(PEA^(+))*** demonstrates a significantly lower non-radiative recombination rate,even though the two types of bulky cations have similar chemical passivation effects on perovskite,which might be explained by the suppressed carrier capture process and improved lattice geometry *** resulting PSCs achieve an exceptional power conversion efficiency(PCE)of 25.5%with a record-high opencircuit voltage(V_(OC))of 1.20 V for narrow bandgap perovskite(FAPbI_(3)).The established correlations between electron-phonon coupling and non-radiative decay provide design and screening criteria for more effective passivators for highly efficient PSCs approaching the Shockley-Queisser limit.

关键词： Electron-phonon coupling A-site cation engineering Non-radiative recombination

COUPLED-MODE SUBSPACE PERTURBATION METHOD FOR STRUCTURAL DYNAMIC MODIFICATION

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Chinese Journal of Aeronautics 1992年第4期 284-289页

作者： Sun Jiu-hou, Zhu De-mao(Nanjing Aeronautical Institute

A coupled-mode subspace perturbation method is studied in this *** matrixperturbation method is an important method for reanalyzing the structural dynamic characteristicswhen the mass and stiffness matrices of the structural system have *** the closed natural frequencies exist in the structural system and the changesof the mass and stiffness matrices are somewhat larger,it results in these modes *** this case,the ordinary matrix perturbation method is *** making thecoordinate transformation by initial modes the vibration modes are divided into twoclasses:separated and *** coupled-mode subspaces are spanned by the *** the next coupled-mode space modal transformation,the complete perturbedeigensolutions are given by the present coupled-mode subspace perturbation *** algorithm of the method is *** for requiring the solutions of a low-ordereigenvalue problems of the coupled-mode subspace,it only requires matrix *** method is an extension of the matrix perturbation method,when the closed,repeatedand both natural frequencies *** is demonstrated by the sample problems thatthe method presented here is accurate and efficient.

关键词： mode COUPLED-MODE SUBSPACE PERTURBATION METHOD FOR STRUCTURAL DYNAMIC MODIFICATION