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Analysis of Short-circuit Characteristics and Calculation of Steady-state Short-circuit Current for DFIG Wind Turbine

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电力系统自动化 2012年第8期36卷 115-121页

作者： xiong, Xiaofu Ouyang, Jinxin State Key Laboratory of Power Transmission Equipment and System Security Chongqing University Chongqing 400030 China

Large-scale doubly-fed induction generator(DFIG)wind turbines are connected to the grid and required to remain grid-connection during faults,the short-circuit current contributed by the generation has become a significant ***,the traditional calculation methods aiming at synchronous generators cannot be directly applied to the DFIG wind turbines.A new method is needed to calculate the short-circuit current required by the planning,protection and control of the power *** short-circuit transition of DFIG under symmetrical and asymmetric short-circuit conditions are mathematically deduced,and the short-circuit characteristics of DFIG are analyzed.A new method is proposed to calculate the steady-state short-circuit current of DFIG based on the derived *** time-domain simulations are conducted to verify the accuracy of the proposed method.

关键词：双馈风力发电机短路电流短路特性计算变速恒频稳态双馈感应发电机非对称短路

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车镇凹陷大王北地区调节构造分析

油气地质与采收率 2005年第6期12卷 23-25页

作者：熊伟中国石油大学(华东)

车镇凹陷大王北地区油气十分富集,复杂的地质结构和构造演化过程导致了该区圈闭类型十分丰富。通过对大王北地区构造的几何形态和演化特征分析,认为该区东部和西部的鼻状构造是埕南边界断层分段差异活动与大1断层活动相互作用下形成的... 详细信息

车镇凹陷大王北地区油气十分富集,复杂的地质结构和构造演化过程导致了该区圈闭类型十分丰富。通过对大王北地区构造的几何形态和演化特征分析,认为该区东部和西部的鼻状构造是埕南边界断层分段差异活动与大1断层活动相互作用下形成的对向并行型调节构造。综合研究表明,调节构造一般发育在沉积中心转移部位,圈闭类型丰富,油气成藏条件良好,虽然目前研究程度较低,但仍具有极大的勘探潜力。

关键词：调节构造断鼻构造油气成藏大王北地区

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双重运动:全球化并非不可逆转

外交评论（外交学院学报） 2007年第5期24卷 108-112页

作者：熊炜外交学院外交学系北京100037

美国《纽约时报》著名专栏作家托马斯·弗里德曼的著作总能造成洛阳纸贵的效果。前不久，他论述全球化的一部畅销专著《世界是平的：“凌志汽车”和“橄榄树”的视角》被翻译成中文出版，同样引起国内知识界的广泛关注。弗里德曼在这部... 详细信息

美国《纽约时报》著名专栏作家托马斯·弗里德曼的著作总能造成洛阳纸贵的效果。前不久，他论述全球化的一部畅销专著《世界是平的：“凌志汽车”和“橄榄树”的视角》被翻译成中文出版，同样引起国内知识界的广泛关注。弗里德曼在这部书中用生动的语言和清晰地论述再次强调了有关全球化的经典命题：全球化是一个不可逆转的过程。为什么全球化总是被人们描述成为一个不可逆转的过程？当代国际关系是否真的只有这一种发展趋势？

关键词：全球化不可逆双重运动《纽约时报》弗里德曼专栏作家凌志汽车发展趋势

Joint Iterative Pilot Assisted Channel Estimation and Detection in Turbo OFDM System

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通讯和计算机（中英文版） 2005年第1期2卷 69-74页

作者： YANG Haifen xiong Yong BAI wei BU Zhiyong LI Guangjun School of Communication ＆ Information University of Electronic Science and Technology of China Chengdu 610054 China Shanghai Research Center for Wirelcss Commuications Shanghai 200050 China

Curative effect of heat-sensitive moxibustion on chronic persistent asthma: a multicenter randomized controlled trial

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Journal of Traditional Chinese Medicine 2013年第5期33卷 584-591页

作者： Rixin Chen Mingren Chen Jun xiong Zhenhai Chi B0 Zhang Ning Tian Zhenhua Xu Tangfa Zhang Wanyao Li wei Zhang Xiaofeng Rong Zhen Wang Gang Sun Baohe Ge Guoxiong Yu Nanchang Song Department of Acupuncture and Rehabilitation Hospital Affiliated to Jiangxi University of Traditional Chi-nese Medicine Department of Rehabilitation Guangdong Hos-pital of Combination of Traditional Chinese Medicine with Western Medicine Department of Pneumology Guangdong Hos-pital of Traditional Chinese Medicine Department of Acupuncture First Hospital of Wuhan Institute of Acupuncture and Massage Guang-zhou University of Traditional Chinese Medicine Department of Pneumology First Hospital Affili-ated to Nanchang University Department of Rehabilitation First Hospi-tal Affiliated to Chongqing Medical University Department of Acupuncture First Hospital Af-filiated to Zhejiang University of Traditional Chinese Medi-cine Department of Acupuncture Suzhou Hospital of TCM Department of Acupuncture Hospital Affiliated to Shandong University of Traditional Chinese Medicine Department of Acupuncture Guangdong Dis-abled Soldier Hospital Department of Acupuncture Nanchang Hospital of combination of Traditional Chinese Medicine with Western Medicine

OBJECTIVE:To compare the curative effects of heat-sensitive moxibustion with conventional drugs on chronic persistent asthma and seek a valuable therapy to replaceWestern ***:The participants in this multi-center,randomized,and controlled study were randomly divided into two groups:group A(n=144),treated with heat-sensitive moxibustion(50 sessions)and group B(n=144),treated with Seretide(salmeterol50μg/fluticasone 250μg,twice a day).The scores of asthma control test(ACT),forced expiratory volume in 1 second(FEV1),peak expiratory flow(PEF),and attack frequency were measured after 15,30,60,and 90 days of *** followed up3 and 6 months after ***:There was a significant difference(P=0.0002)in the ACT score and lung function between the two groups after 3 months of treatment and(P=0.000 03)during the follow-up *** addition,heat-sensitive moxibustion reduced attack frequency in the period from inclusion to the6-month follow-up ***:This study shows that heat-sensitive moxibustion may have a comparable curative effect toSeretide(salmeterol/fluticasone)on asthma.

关键词： Moxibustion Asthma Randomized controlled trial Heat sensitive Seretide

Study on the synthesis of spin labeled poly(styrene-co-maleic acid)s and their segmental motion

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Magnetic Resonance Letters 2022年第2期2卷 80-90,I0002页

作者： Kaleem-Ur-Rahman Naveed Li Wang Haojie Yu Qian Zhang wei xiong Raja Summe Ullah Ahsan Nazir Muhammad Usman Shah Fahad Amin Khan Md Alim Uddin Di Shen State Key Laboratory of Chemical Engineering College of Chemical&Biological EngineeringZhejiang UniversityHangzhou310027China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou310003China

Study of the segmental mobility of polymer chains is important when the polymer is used as drag reduction agents of crude *** spin resonance(ESR)spectroscopy can provide important information about segmental dynamics of polymer chains,which is related to their *** this article,we employed an amphiphilic polymer to study the effect of hydrophilic/hydrophobic balance of the polymers on the segmental motion of polymer ***(styrene-co-maleic acid)(PSMA)was spin labeled with 4-amino TEMPO radicals by increasing the concentration of radical moiety on the polymer *** PSMA and spin labeled-PSMAs(SL-PSMAs)were characterized by nuclear magnetic resonance(NMR),Fourier transform infrared(FT-IR)spectroscopy,Cyclic voltammetry(CV)and ESR ***-polymer complexes(IPCs)of SL-PSMA-2 were prepared by employing polyethylene glycols(PEGs)of varying molecular *** results showed that the increased hydrophobic interactions of nitroxide radicals on the SLPSMAs’chains reduced the rotational mobility of spin labels and the random coil-toglobular transition of polymer chains occurred at higher pH value for SL-PSMAs,which showed a slow motion component in the ESR spectra of ***,by increasing the molecular weight of PEGs in IPCs the complexation was increased,which also reduced the rotational motion of spin labels due to interpolymer hydrogen bonding causing a slow motion component in the ESR spectra.©2021 The Authors.

关键词： Electron spin resonance(ESR) Spin labeling Nitroxide radicals poly(styrene-co-maleic acid)s Segmental motion

Short-Term Reliability Evaluation of Transmission System under Strong Wind and Rain

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Journal of Power and Energy Engineering 2014年第4期2卷 665-672页

作者： Yanan wei Qing Yang Xiaofu xiong Jian Wang Shijie Weng Yunnan Power Grid Corporation Kunming China State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing China

The impact of strong wind and rain loads will adversely affect the reliability of the overhead lines, it’s necessary to study changes in risk of transmission system and establish the reliability model of overhead lines through the strong wind and rain loads. In this article, the stochastic properties of overhead lines’ strength and loads were used, according to principles of structural reliability, time-dependent failure probability model of overhead lines was established under the impact of strong wind and rain loads. Simulation of the IEEE-79 system demonstrates that failure probability model is effective. This simulation result also shows that the impact of strong wind and rain loads will seriously affect reliability indices of system loads, rain loads cannot be ignored under strong wind and rain loads.

关键词： Strong Wind and Rain Loads Transmission Line Structural Reliability Reliability Modeling

Continuity Scaling: A Rigorous Framework for Detecting and Quantifying Causality Accurately

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Research 2022年第4期2022卷 137-146页

作者： xiong Ying Si-Yang Leng Huan-Fei MaD Qing Nie Ying-Cheng Lai wei Lin School of Mathematical Sciences SCMSand SCAMFudan UniversityShanghai 200433China Research Institute for Inteligent Complex Systems CCSBand LCNBIFudan UniversityShanghai 200433China State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Institutes of Brain ScienceFudan UniversityShanghai 200032China Institute of AI and Robotics Academy for Engineering and TechnologyFudan UniversityShanghai 200433China School of Mathematical Sciences Soochow UniversitySuzhou 215006China Department of Mathematics Department of Developmental and Cll BiologyAnd NSF-Simons Center for Multiscale Cell Fate ResearchUniversity of CaliforniaIrvineCA 92697-3875USA School of Electrical ComputerAnd Energy EngineeringArizona State UniversityTempeArizona 85287-5706USA Shanghai Artificial Intelligence Laboratory Shanghai 200232China

Data-based detection and quantification of causation in complex,nonlinear dynamical systems is of paramount importance to science,engineering,and *** by the widely used methodology in recent years,the cross-map-based techniques,we develop a general framework to advance towards a comprehensive understanding of dynamical causal mechanisms,which is consistent with the natural interpretation of *** particular,instead of measuring the smoothness of the cross-map as conventionally implemented,we define causation through measuring the scaling law for the continuity of the investigated dynamical system *** uncovered scaling law enables accurate,reliable,and eficient detection of causation and assessment of its strength in general complex dynamical systems,outperforming those existing representative *** continuity scaling-based framework is rigorously established and demonstrated using datasets from model complex systems and the real world.

关键词： dynamical scaling continuity

石英玻璃的紫外飞秒激光光丝高精度加工技术研究

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中国激光 2024年第12期51卷 465-473页

作者：薛波贾平岗安国文苏建慧王灏荃杨楠熊继军中北大学省部共建动态测试技术国家重点实验室山西太原030051

石英玻璃的高精度加工在微机电器件封装、光纤传感和微电子封装等领域有着巨大的需求。为进一步提升加工精度和加工质量,本课题组开展了基于光丝效应的343 nm紫外飞秒激光加工实验,研究了激光焦点位置、脉冲能量、重复频率、扫描速度和... 详细信息

石英玻璃的高精度加工在微机电器件封装、光纤传感和微电子封装等领域有着巨大的需求。为进一步提升加工精度和加工质量,本课题组开展了基于光丝效应的343 nm紫外飞秒激光加工实验,研究了激光焦点位置、脉冲能量、重复频率、扫描速度和扫描次数对石英玻璃光丝损伤形貌的影响,并在此基础上优化工艺参数,对石英玻璃进行了快速切割和打孔实验。研究结果表明:在激光重复频率一定时,脉冲能量越大,光丝损伤越深;脉冲能量不变时,重复频率越高,光丝损伤深度越大;扫描速度的降低会增加损伤深度,但也会使加工表面的熔融物增多;增加扫描次数能显著提升加工质量。利用激光光丝加工方法切割得到的石英玻璃断面接近垂直且粗糙度小于1μm,微孔加工的尺寸精度可达到±2μm。

关键词：飞秒激光石英玻璃光丝效应精密切割微孔加工