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Dynamic Couplingand Cooperative Control for Multi-paralleled Doubly Fed Induction Generator Wind Farms during Symmetrical Low Voltage Ride-through in a Weak Grid

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Protection and Control of Modern Power Systems 2024年第3期9卷 112-125页

作者： lei guan Jun Yao the College of Electrical Engineering at Chongqing University ChongqingChina the State Key Laboratory of Power Transmission Equipment Technology School of Electrical EngineeringChongqing UniversityChongqing 400044China

In multi-fed grid-connected systems,there are complex dynamic interactions between different pieces of *** in situations of weak-grid faults,the dynamic coupling between equipment becomes more *** may cause the system to experience small-signal instability during the fault *** this paper,multi-paralleled doubly fed induction generator(DFIG)-based wind farms(WFs)are taken as an example to study the dynamic coupling within a multi-fed system during fault steady-state of symmetrical low voltage ride-through(LVRT)in a weak *** analysis reveals that the dynamic coupling between WFs will introduce a damping shift to each *** inevitably affects the system’s dynamic stability and brings the risk of small-signal instability during fault steady-state in LVRT *** the distance to fault location and fault severity will exacerbate the dynamic coupling between *** of the dynamic coupling,adjusting the control state of one WF will affect the stability of the remaining WFs in the ***,a cooperative control strategy for multi-paralleled DFIG WFs is proposed to improve dynamic stability during *** analysis and the effectiveness of the proposed control strategy are verified by modal analysis and simu-lation.

关键词： Doubly fed induction generator(DFIG) wind farms(WFs) dynamic stability low voltage ride through(LVRT) weak grid dynamic coupling

Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020

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Journal of Mountain Science 2024年第9期21卷 3031-3046页

作者： GAO Bing LIU Enqin YANG Yang YANG Man YAO Yang guan lei FENG Yiwen College of Geography and Planning Chengdu University of TechnologyChengdu 610059China Key Laboratory of Smart Earth Beijing 100029China Sichuan Provincial Soil and Water Conservation Ecological Environment Monitoring Station Chengdu 610041China College of Earth and Planetary Sciences Chengdu University of TechnologyChengdu 610059China

Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige ***,the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain ***,clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the ***,we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI)as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the *** find a tendency of vegetation greening from 2001 to 2020,with significant greening accounting for 21.44%of the entire ***,browning area expanded rapidly after *** temperatures are the primary driver of vegetation changes in the Zoige *** variations and human activities were responsible for 65.57%and 34.43%of vegetation greening,and 39.14%and 60.86%of vegetation browning,respectively,with browning concentrated along the Yellow,Black and White *** to 2001-2010,the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020.

关键词： Vegetation change Climate change Residual trend analysis Geodetector Human activities Zoige plateau

Quantitative contributions of climate change and human activities to vegetation dynamics in the Zoige Plateau from 2001 to 2020

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Journal of Mountain Science 2024年第09期 3031-3046页

作者： GAO Bing LIU Enqin YANG Yang YANG Man YAO Yang guan lei FENG Yiwen College of Geography and Planning Chengdu University of Technology Key Laboratory of Smart Earth Sichuan Provincial Soil and Water Conservation Ecological Environment Monitoring Station College of Earth and Planetary Sciences Chengdu University of Technology

Climate change and human activities such as overgrazing and rapid development of tourism simultaneously affected the vegetation of the Zoige Plateau. However, the spatiotemporal variations of vegetation and the relative contributions of climate change and human activities to these vegetation dynamics remain unclear. Therefore, clarifying how and why the vegetation on the Zoige Plateau changed can provide a scientific basis for the sustainable development of the region. Here, we investigate NDVI trends using the Normalized Difference Vegetation Index(NDVI) as an indicator of vegetation greenness and distinguish the relative effects of climate changes and human activities on vegetation changes by utilizing residual trend analysis and the *** find a tendency of vegetation greening from 2001 to 2020, with significant greening accounting for 21.44% of the entire region. However, browning area expanded rapidly after 2011. Warmer temperatures are the primary driver of vegetation changes in the Zoige Plateau. Climatic variations and human activities were responsible for 65.57% and 34.43% of vegetation greening, and 39.14% and 60.86% of vegetation browning, respectively, with browning concentrated along the Yellow, Black and White Rivers. Compared to 2001–2010, the inhibitory effect of human activity and climate fluctuations on vegetation grew dramatically between 2011 and 2020.

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基于SNPP/VIIRS卫星数据的海温锋检测算法研究

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中国海洋大学学报（自然科学版） 2024年第9期54卷 21-29页

作者：于杰管磊中国海洋大学三亚海洋研究院海南三亚572024 中国海洋大学信息科学与工程学部海洋技术学院山东青岛266100

本文采用SNPP/VIIRS(Suomi national polar-orbiting partnership/Visible infrared imaging radiometer suite)卫星海表温度数据对锋面检测算法进行对比分析,包括Sobel算法、Canny算法、引力模型法、直方图分析法和熵算法。通过分析上述算法中间结果、单日海温锋检测结果以及月度锋面概率分布的差别与特征,再结合各算法特点发现,在锋面识别中由于各算法的底层逻辑不同,造成了对海温锋定义难以统一的问题,因此各算法检测出的海温锋各有特点,适合不同的研究和应用需求,实际应用时要根据研究需要和实际情况选择合适的算法。各算法的特点为:Canny算法、引力模型法、Sobel算法、熵算法对强锋面的检测能力依次递减,对弱锋面的检测能力依次递增,抗噪性递减,直方图分析法检测出的锋面表现出较强的连续性,锋面光滑、清晰且连贯,抗噪性较好;各算法适用场合为:以梯度计算为基础的Sobel算法或者其他梯度类算法适用于精确计算温度变化程度的应用场景,Canny算法适用于强锋面的研究,引力模型法适用于应用噪声较大的数据检测锋面或者强锋面的检测,熵算法适用于弱锋面的检测,直方图分析法比较适合分析连续的长锋面。

关键词：卫星海表温度海温锋锋面检测算法

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人工智能驱动开源大数据分析工作提质升级

信息安全研究 2024年第5期10卷 390-395页

作者：于锐管磊多维身份识别与可信认证技术国家工程研究中心中国计算机学会计算机安全专业委员会公安部第一研究所

以人工智能为代表的智能技术的革命性突破在众多领域带来颠覆性的变革,并逐渐向大数据分析领域渗透.网络开源数据凭借其广泛性、可获得性、多样性等优势,使其在社会公共安全治理工作中得到越来越多的重视,但也存在信息量大、数据过载、... 详细信息

以人工智能为代表的智能技术的革命性突破在众多领域带来颠覆性的变革,并逐渐向大数据分析领域渗透.网络开源数据凭借其广泛性、可获得性、多样性等优势,使其在社会公共安全治理工作中得到越来越多的重视,但也存在信息量大、数据过载、真实性难以保证等固有缺陷,利用人工智能技术可重塑开源数据收集、存储和处理的方式,也会改变智能数据分析与生产应用的关键环节.本文探讨了人工智能背景下开源数据分析工作面临的新机遇和挑战,阐述了依托人工智能技术进行开源大数据分析的工作方法和实践路径,对智能化大数据分析工作的改进和提升进行了有益的探索.

关键词：大数据分析人工智能技术智能数据分析开源数据革命性突破固有缺陷智能化可重塑

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北极区域的FY-3C/VIRR热红外通道定标精度评估

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海洋湖沼通报 2024年第1期46卷 38-46页

作者：李卓敏管磊中国海洋大学信息科学与工程学院山东青岛266100 中国海洋大学三亚海洋研究院海南三亚572024 青岛海洋科学与技术试点国家实验室区域海洋动力学与数值模拟功能实验室山东青岛266237

北极区域的海表温度(Sea Surface Temperature,SST)可以控制海冰增长、冰雪消融和表面大气能量交换,全球的温度变化及趋势在北极存在放大现象,因此北极海温的监测对于全球气候变化监测十分重要。卫星传感器热红外通道亮温数据可用于反... 详细信息

北极区域的海表温度(Sea Surface Temperature,SST)可以控制海冰增长、冰雪消融和表面大气能量交换,全球的温度变化及趋势在北极存在放大现象,因此北极海温的监测对于全球气候变化监测十分重要。卫星传感器热红外通道亮温数据可用于反演海表温度,其精度对于海表温度的精度有着至关重要的作用。本文以北极为研究区域,对搭载在FY-3C卫星上的可见光红外扫描辐射计(Visible and Infrared Scanning Radiometer,VIRR)热红外通道(11μm、12μm通道)定标精度进行评估,参考传感器为中分辨率成像光谱仪(Moderate-resolution Imaging Spectroradiometer,MODIS)。由于VIRR与MODIS的光谱响应有所不同,本文使用大气辐射传递模型MODTRAN(MODerate resolution atmospheric TRANsmission)进行VIRR和MODIS模拟亮温的计算,将海表参数和大气参数、海表发射率、卫星天顶角、VIRR和MODIS两通道对应的光谱响应曲线分别输入MODTRAN得到VIRR和MODIS两通道的模拟亮温,进而得到VIRR和MODIS 11μm、12μm通道光谱差异。根据VIRR和MODIS两通道观测亮温之差和光谱差异计算两者的实际差值,即二重差分值,得到白天11μm通道平均偏差为-0.41 K,标准偏差为0.26 K,12μm通道平均偏差为-0.47 K,标准偏差为0.30 K;夜间11μm通道平均偏差为-0.35 K,标准偏差为0.21 K,12μm通道平均偏差为-0.44 K,标准偏差为0.22 K。表明在北极区域VIRR热红外通道的定标精度较高。

关键词： VIRR MODIS 热红外通道大气辐射传递模拟

基于自适应加权融合激光雷达和相机的三维目标检测方法

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计算机应用 2024年第S1期44卷 250-255页

作者：董钰婷官磊中国科学院成都计算机应用研究所成都610041 中国科学院大学计算机科学与技术学院北京100049

基于激光雷达和相机融合的三维目标检测技术广泛应用于自动驾驶领域,然而大部分融合方法只是简单组合不同传感器,忽略了不同传感器的感知能力随环境的变化而变化的问题,从而难以精确检测出行人等分辨率较低的目标。针对这一问题,提出一... 详细信息

基于激光雷达和相机融合的三维目标检测技术广泛应用于自动驾驶领域,然而大部分融合方法只是简单组合不同传感器,忽略了不同传感器的感知能力随环境的变化而变化的问题,从而难以精确检测出行人等分辨率较低的目标。针对这一问题,提出一种基于自适应加权融合激光雷达和相机的三维目标检测方法。首先,使用ResNet50+RPN主干网络提取图像的多尺度语义特征,同时,使用动态体素特征编码器将原始点云数据聚合成点云特征;其次,利用自注意力和交叉注意力融合语义特征和点云特征,自适应地为两者的特征图分配权重;最后,将融合后的点特征通过单阶段检测器SECOND(Sparsely Embedded CONvolutional Detection)进行目标边界框回归和分类预测,并且将检测结果在KITTI数据集上验证。实验结果表明,在简单、中等和困难三种难度级别下,该多模态融合方法相较于原始SECOND模型,对汽车和行人的检测精度均有较大的提升,其中行人的检测精度提升最明显;同时,与许多主流的三维目标检测网络相比,所提方法具有更高的精度。

关键词：激光雷达多模态融合三维目标检测注意力机制自动驾驶深度学习

Advances of Pipeline Model Parallelism for Deep Learning Training:An Overview

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Journal of Computer Science & Technology 2024年第3期39卷 567-584页

作者：关磊李东升梁吉业王文剑葛可适卢锡城 College of Science National University of Defense TechnologyChangsha 410073China College of Computer National University of Defense TechnologyChangsha 410073China School of Computer and Information Technology Shanxi UniversityTaiyuan 030006China CCF IEEE

Deep learning has become the cornerstone of artificial intelligence,playing an increasingly important role in human production and ***,as the complexity of problem-solving increases,deep learning models become increasingly intricate,resulting in a proliferation of large language models with an astonishing number of *** model parallelism(PMP)has emerged as one of the mainstream approaches to addressing the significant challenge of training“big models”.This paper presents a comprehensive review of *** covers the basic concepts and main challenges of *** also comprehensively compares synchronous and asynchronous pipeline schedules for PMP approaches,and discusses the main techniques to achieve load balance for both intra-node and inter-node ***,the main techniques to optimize computation,storage,and communication are presented,with potential research directions being discussed.

关键词： deep learning pipeline schedule load balance multi-GPU system pipeline model parallelism(PMP)

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传统技艺类非物质文化遗产传承对策浅析

浙江工贸职业技术学院学报 2024年第1期24卷 44-46页

作者：关雷浙江工贸职业技术学院浙江温州325003

传统技艺类非物质文化遗产体现了当时社会的先进制造水平和人民的审美情趣,直接推动了人类社会的进步。但在人类的发展历程当中,这类非物质文化遗产却逐渐地在人们的日常生活当中变得稀少。通过对传统技艺类非物质文化遗产传承目前所面... 详细信息

传统技艺类非物质文化遗产体现了当时社会的先进制造水平和人民的审美情趣,直接推动了人类社会的进步。但在人类的发展历程当中,这类非物质文化遗产却逐渐地在人们的日常生活当中变得稀少。通过对传统技艺类非物质文化遗产传承目前所面临的问题和困境的分析,提出了开展传统技艺类非物质文化遗产传承与保护的一些现实举措,以期更多年轻人能够了解、欣赏、传承这些独具文化特色的传统技艺。

关键词：传统技艺非物质文化遗产文化遗产传承