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双馈异步风力发电机转子匝间短路故障振动特性分析

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河北大学学报（自然科学版） 2024年第1期44卷 9-16页

作者：庞彬周紫烨齐晓帆郑涵升河北大学质量技术监督学院河北保定071002 河北省新能源汽车动力系统轻量化技术创新中心河北保定071002

针对双馈异步风力发电机转子匝间短路的故障振动机理尚不明确且无法为故障诊断提供理论依据的问题,开展了双馈异步风力发电机转子匝间短路故障振动特性分析.首先,结合有限元仿真及解析推导,分析转子匝间短路下双馈异步风力发电机的气隙... 详细信息

针对双馈异步风力发电机转子匝间短路的故障振动机理尚不明确且无法为故障诊断提供理论依据的问题,开展了双馈异步风力发电机转子匝间短路故障振动特性分析.首先,结合有限元仿真及解析推导,分析转子匝间短路下双馈异步风力发电机的气隙磁密规律,得到转子所受的不平衡磁拉力;然后,考虑转子不平衡磁拉力的情况下构建双馈异步风力发电机转子-轴承系统非线性动力学模型,利用非线性动力学仿真获取转子匝间短路故障下系统的振动仿真信号;最后,在双馈异步风力发电机故障模拟实验台上进行转子匝间短路故障实验,利用实验分析验证非线性动力学仿真结果的有效性.非线性动力学仿真及实验分析结果均表明,转子匝间短路故障下双馈异步风力发电机转子-轴承系统振动信号的频谱存在转频的谐波成分,通过检测转频的谐波分量可诊断双馈异步风力发电机转子匝间短路故障,有效揭示了双馈异步风力发电机转子匝间短路的故障振动机理.

关键词：双馈异步风力发电机转子匝间短路非线性动力学振动特性故障诊断

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A survey of the pursuit-evasion problem in swarm intelligence

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信息与电子工程前沿:英文版 2023年第8期24卷 1093-1116页

作者： Zhenxin MU Jie PAN ziye zhou Junzhi YU Lu CAO State Key Laboratory for Turbulence and Complex Systems Department of Advanced Manufacturing and RoboticsCollege of EngineeringPeking UniversityBeijing 100871China National Innovation Institute of Defense Technology Beijing 100071China

For complex functions to emerge in artificial systems,it is important to understand the intrinsic mechanisms of biological swarm behaviors in *** this paper,we present a comprehensive survey of pursuit–evasion,which is a critical problem in biological ***,we review the problem of pursuit–evasion from three different perspectives:game theory,control theory and artificial intelligence,and bio-inspired *** we provide an overview of the research on pursuit–evasion problems in biological systems and artificial *** summarize predator pursuit behavior and prey evasion behavior as predator–prey ***,we analyze the application of pursuit–evasion in artificial systems from three perspectives,i.e.,strong pursuer group *** evader group,weak pursuer group *** evader group,and equal-ability ***,relevant prospects for future pursuit–evasion challenges are *** survey provides new insights into the design of multi-agent and multi-robot systems to complete complex hunting tasks in uncertain dynamic scenarios.

关键词： Swarm behavior Pursuit-evasion Artificial systems Biological model Collective motion

空间引力波探测望远镜指向偏差地面高精度测量技术研究

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光电工程 2024年第2期51卷 96-107页

作者：宋奇林李杨周子夜肖亚维杨金生黄林海顾乃庭饶长辉自适应光学全国重点实验室四川成都610209 中国科学院大学北京100049 中国科学院光电技术研究所四川成都610209 中国科学院自适应光学重点实验室四川成都610209

星载望远镜是实现空间引力波探测的核心组成部分。由于各星座之间传输距离达到109 m量级,对望远镜指向精度提出了nrad量级的严苛要求,而指向偏差高精度测量和定标就成为实现空间引力波探测星载望远镜高精度指向的前提。为实现星载望远... 详细信息

星载望远镜是实现空间引力波探测的核心组成部分。由于各星座之间传输距离达到109 m量级,对望远镜指向精度提出了nrad量级的严苛要求,而指向偏差高精度测量和定标就成为实现空间引力波探测星载望远镜高精度指向的前提。为实现星载望远镜指向偏差地面测试及传感器定标需求,本文提出基于哈特曼原理的新型指向偏差高精度测量方法,采用多子孔径空间复用思想降低各类随机误差对测量精度的影响,显著提升了指向偏差测量精度。本文根据传感器参数与指向偏差测量精度之间的定量关系,对哈特曼传感器参数进行了分析优化,并分析了星载望远镜指向偏差测量精度。研究结果表明:采用基于哈特曼原理的多子孔径空间复用方法,可以实现对星载望远镜指向偏差0.62nrad的高精度测量,为空间引力波探测望远镜地面测试及在轨传感器定标提供了可行途径和参考。

关键词：星载望远镜指向偏差测量哈特曼多子孔径空间复用

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工艺参数对电弧增材制造工件的影响

河北冶金 2024年第2期 32-38页

作者：王鑫赵津嫚王倩武佳璇周子烨河北科技大学材料科学与工程学院河北石家庄050018

电弧增材制造具有高沉积速率、高质量、无尺寸限制的特点,能够满足具有高机械性能要求的中大型部件的制作需求。电弧增材制造AlMg合金过程中制备工艺参数对工件的宏观形貌、微观组织及力学性能均会产生重要影响。本文通过研究焊丝盘松... 详细信息

电弧增材制造具有高沉积速率、高质量、无尺寸限制的特点,能够满足具有高机械性能要求的中大型部件的制作需求。电弧增材制造AlMg合金过程中制备工艺参数对工件的宏观形貌、微观组织及力学性能均会产生重要影响。本文通过研究焊丝盘松紧度、焊接速度、焊接电流和层间等待时间对电弧增材制造AlMg合金成形的影响,确定了最佳制备工艺参数。研究表明,焊丝盘松紧度为2时,增材设备送丝顺畅,焊道成形效果好;焊道成形与热输入有关,焊接速度越小,增材过程产生的热输入值越大,当焊接速度为36 cm/min时,单道焊缝的成形缺陷最少,成形效果良好;焊接电流越大,增材过程产生的热输入值就越大,当焊接电流为65 A时,焊道形貌均匀;层间等待时间增加到150 s时,合金晶粒为均匀细小的等轴晶,平均晶粒尺寸降至52.9μm。

关键词：电弧增材制造焊接速度焊接电流成形形貌层间等待时间

考虑不平衡磁拉力的双馈异步风力发电机轴承外圈故障动力学建模

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电机与控制应用 2024年第3期51卷 30-37页

作者：庞彬郑涵升周紫烨王博巍郝紫阳河北大学质量技术监督学院河北保定071002 河北大学计量仪器与系统国家地方联合工程研究中心河北保定071002

轴承故障会引起双馈异步风力发电机转子气隙变化,产生不平衡磁拉力(UMP)。为准确揭示双馈异步风力发电机轴承故障振动特性,开展了考虑UMP的双馈异步风力发电机轴承外圈故障动力学建模研究。首先,基于赫兹接触理论构建了轴承外圈故障模型... 详细信息

轴承故障会引起双馈异步风力发电机转子气隙变化,产生不平衡磁拉力(UMP)。为准确揭示双馈异步风力发电机轴承故障振动特性,开展了考虑UMP的双馈异步风力发电机轴承外圈故障动力学建模研究。首先,基于赫兹接触理论构建了轴承外圈故障模型;然后,推导了正常和轴承故障下发电机转子的气隙磁密,得到了发电机转子受到的UMP解析式;最后,采用Runge-Kutta法对模型进行求解,得到了轴承故障振动响应。试验分析表明:所提动力学模型能够有效揭示双馈异步风力发电机轴承故障振动信号的双冲击现象,UMP激励会影响风力发电机轴承外圈故障振动信号的调制特性。为风力发电机轴承故障诊断提供了新的理论参考。

关键词：不平衡磁拉力动力学建模风力发电机轴承故障诊断

CREDIT-X1local:A reference dataset for machine learning seismology from ChinArray in Southwest China

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Earthquake Science 2024年第2期37卷 139-157页

作者： Lu Li Weitao Wang ziye Yu Yini Chen Institute of Geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Zhejiang Earthquake Agency HangzhouZhejiang 310013China

High-quality datasets are critical for the development of advanced machine-learning algorithms in ***,we present an earthquake dataset based on the ChinArray Phase I records(X1).ChinArray Phase I was deployed in the southern north-south seismic zone(20°N-32°N,95°E-110°E)in 2011-2013 using 355 portable broadband seismic ***-X1local,the first release of the ChinArray Reference Earthquake Dataset for Innovative Techniques(CREDIT),includes comprehensive information for the 105,455 local events that occurred in the southern north-south seismic zone during array observation,incorporating them into a single HDF5 *** 100-Hz sampled three-component waveforms are organized by event for stations within epicenter distances of 1,000 km,and records of≥200 s are included for each *** types of phase labels are *** first includes manually picked labels for 5,999 events with magnitudes≥2.0,providing 66,507 Pg,42,310 Sg,12,823 Pn,and 546 Sn *** second contains automatically labeled phases for 105,442 events with magnitudes of−1.6 to *** phases were picked using a recurrent neural network phase picker and screened using the corresponding travel time curves,resulting in 1,179,808 Pg,884,281 Sg,176,089 Pn,and 22,986 Sn ***,first-motion polarities are included for 31,273 Pg *** event and station locations are provided,so that deep learning networks for both conventional phase picking and phase association can be trained and *** CREDIT-X1local dataset is the first million-scale dataset constructed from a dense seismic array,which is designed to support various multi-station deep-learning methods,high-precision focal mechanism inversion,and seismic tomography ***,owing to the high seismicity in the southern north-south seismic zone in China,this dataset has great potential for future scientific discoveries.

关键词： earthquake dataset machine learning Pg/Sg/Pn/Sn phase picking P-wave first-motion polarity

Impact of atmospheric circulations on droughts and drought propagation over China

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Science China Earth Sciences 2024年第8期67卷 2633-2648页

作者： ziye GU Lei GU Jiabo YIN Wei FANG Lihua XIONG Jun GUO Ziyue ZENG Jun XIA School of Civil and Hydraulic Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Water Resources Engineering and Management Wuhan 430072China Changjiang River Scientific Research Institute Wuhan 430010China

The GRACE satellite mission provides a new approach for monitoring,tracking,and assessing drought conditions by detecting changes in Earth's gravitational fields and inversing signals of terrestrial water storage *** studies of terrestrial water storage anomalies related droughts paid rare attention to the behind atmospheric physical mechanisms,nor quantified the risk propagation patterns between terrestrial water storage deficits and hydrological or agricultural *** this study,we first extract terrestrial water storage(TWS) droughts,hydrological droughts,and agricultural droughts by using multiple variables including TWS from the GRACE/GRACE-FO satellites,runoff and soil moisture from the ERA5-Land reanalysis *** then identify key atmospheric and oceanic oscillation indices affecting water deficits by employing machine learning *** characterize the joint distributions between drought duration and severity by using the Copula function and quantify the risk propagation of hydrological and agricultural droughts to TWS *** results show that:(1) From 2002 to 2021,there is a significant decrasing trend of TWS in China;the WPIO group atmospheric circulation indices(sea surface temperature index within the Western Pacific and Indian Ocean) contributes the most to ***,the sea surface temperature anomalies within the NINO 3.4 region as well as the Western Pacific Warm Pool area index show significantly positive correlation relationships with TWS in southern China;(2) The northwestern China,the Yangtze River basin,and the downstream of the Pearl River basin are the hotspots of TWS ***,the hotspots of hydrological droughts locate in northwestern China and the hotspots of agricultural droughts locate in South China and eastern Tibetan Plateau;(3) The elastic coefficients of hydrological droughts propagating to TWS droughts are higher than those of agricultural droughts,indicating that the TWS droughts

关键词： GRACE satellites Drought Drought propagation Atmospheric circulation Copula function

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Continuous-wave operation of 1550 nm low-threshold triple-lattice photonic-crystal surface-emitting lasers

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Light(Science & Applications) 2024年第3期13卷 446-453页

作者： ziye Wang Xia Liu Pinyao Wang Huanyu Lu Bo Meng Wei Zhang Lijie Wang Yanjing Wang Cunzhu Tong State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Central Research Institute Planning Dept 2012 LabsHuawei Technologies Company Ltd.Shenzhen 518129China

Benefitting from narrow beam divergence,photonic crystal surface-emitting lasers are expected to play an essential role in the ever-growing fields of optical communication and light detection and *** operating with 1.55μm wavelengths have attracted particular attention due to their minimum fiber loss and high eye-safe ***,high interband absorption significantly decreases their performance at this 1.55μm ***,stronger optical feedback is needed to reduce their threshold and thus improve the output *** this goal,photonic-crystal resonators with deep holes and high dielectric contrast are often ***,the relevant techniques for high-contrast photonic crystals inevitably complicate fabrication and reduce the final *** this paper,we demonstrate the first continuous-wave operation of 1.55μm photonic-crystal surface-emitting lasers by using a‘triple-lattice photonic-crystal resonator’,which superimposes three lattice point groups to increase the strength of in-plane optical *** this geometry,the in-plane 180°coupling can be enhanced threefold compared to the normal single-lattice *** theoretical and experimental investigations demonstrate the much lower threshold current density of this structure compared to‘single-lattice’and‘double-lattice’photonic-crystal resonators,verifying our design *** findings provide a new strategy for photonic crystal laser miniaturization,which is crucial for realizing their use in future high-speed applications.

关键词： resonator crystal lattice

N,S,Br co-doped carbon dots:One-step synthesis and fluorescent detection of 6-mercaptopurine in tablet

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Journal of Pharmaceutical Analysis 2024年第2期14卷 291-293页

作者： Qi Wang Ying Cheng Lifeng Ding Shengling Li Jie Zhang Yulan Niu ziye Jing Chemistry&Chemical Engineering Department Taiyuan Institute of TechnologyTaiyuan030008China Department of Anesthesiology First Hospital of Shanxi Medical UniversityTaiyuan030001China

6-mercaptopurine(6-MP),a purine derivative(3,7-dihydropurine-6-thione),has been utilized as an effective immunosuppressive drug for clinically treating leukemia and other autoimmune diseases[1].6-MP and its corresponding metabolites can suppress the function of RnaseH,and thus they are cytotoxic and threaten the human health[2].Therefore,the accurate quantification of 6-MP is *** date,researchers continue to expend considerable effort in developing 6-MP detection *** analysis eliminates disadvantages,such as toxic solvents,expensive equipment.

关键词： purine synthesis eliminate