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A Deep Learning Approach for Forecasting Thunderstorm Gusts in the Beijing–Tianjin–Hebei Region 被引量:1
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作者 Yunqing LIU Lu YANG +3 位作者 Mingxuan CHEN Linye SONG Lei HAN jingfeng xu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1342-1363,共22页
Thunderstorm gusts are a common form of severe convective weather in the warm season in North China,and it is of great importance to correctly forecast them.At present,the forecasting of thunderstorm gusts is mainly b... Thunderstorm gusts are a common form of severe convective weather in the warm season in North China,and it is of great importance to correctly forecast them.At present,the forecasting of thunderstorm gusts is mainly based on traditional subjective methods,which fails to achieve high-resolution and high-frequency gridded forecasts based on multiple observation sources.In this paper,we propose a deep learning method called Thunderstorm Gusts TransU-net(TGTransUnet)to forecast thunderstorm gusts in North China based on multi-source gridded product data from the Institute of Urban Meteorology(IUM)with a lead time of 1 to 6 h.To determine the specific range of thunderstorm gusts,we combine three meteorological variables:radar reflectivity factor,lightning location,and 1-h maximum instantaneous wind speed from automatic weather stations(AWSs),and obtain a reasonable ground truth of thunderstorm gusts.Then,we transform the forecasting problem into an image-to-image problem in deep learning under the TG-TransUnet architecture,which is based on convolutional neural networks and a transformer.The analysis and forecast data of the enriched multi-source gridded comprehensive forecasting system for the period 2021–23 are then used as training,validation,and testing datasets.Finally,the performance of TG-TransUnet is compared with other methods.The results show that TG-TransUnet has the best prediction results at 1–6 h.The IUM is currently using this model to support the forecasting of thunderstorm gusts in North China. 展开更多
关键词 thunderstorm gusts deep learning weather forecasting convolutional neural network TRANSFORMER
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冬奥会复杂山地百米尺度10m风速预报的机器学习订正对比试验 被引量:1
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作者 徐景峰 宋林烨 +2 位作者 陈明轩 杨璐 韩雷 《大气科学》 CSCD 北大核心 2023年第3期805-824,共20页
本文以传统机器学习算法XGBoost和深度学习算法CU-Net为基础,针对北京快速更新无缝隙融合与集成预报系统(RISE系统)预报的北京冬奥会延庆及张家口赛区100米分辨率的冬季近地面10 m风速数据,进行每日逐小时起报的未来逐6小时间隔的冬奥... 本文以传统机器学习算法XGBoost和深度学习算法CU-Net为基础,针对北京快速更新无缝隙融合与集成预报系统(RISE系统)预报的北京冬奥会延庆及张家口赛区100米分辨率的冬季近地面10 m风速数据,进行每日逐小时起报的未来逐6小时间隔的冬奥高山站点及其周边地区风速预报偏差订正方法研究和对比分析。对于站点订正,首先将RISE系统预测的10 m风速插值到对应的自动气象站站点,然后根据风速等级表归类,针对每个分类单独构建XGBoost模型,每个区间模型合并后形成L-XGBoost,使用均方根误差和预报准确率作为评分标准,结果表明风速归类的L-XGBoost算法订正效果比不归类的原始XGBoost模型有一定提升,说明在传统机器学习中加入归类方法有助于改善复杂山地站点风速预报技巧。对于站点及其周边地区风速订正,本文在CUNet模型基础上,通过引入不同深度的CU-Net子网络,构建了新的算法模型CU-Net++,并考虑了预报日变化误差和复杂地形对10 m风速的影响,以自动气象站为中心构建空间小区域样本数据,对RISE系统风速预报偏差进行订正。试验结果表明,CU-Net和CU-Net++均可以充分挖掘时间和空间维度的风场变化规律,且CU-Net++模型风速订正结果优于CU-Net模型,有效降低了RISE产品的格点风速预报误差,也发现预报误差和复杂地形的引入对10 m风速偏差订正起到重要的正向作用。 展开更多
关键词 百米尺度预报 复杂山地 机器学习 风速订正
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Stress-deconcentrated ultrasensitive strain sensor with hydrogen-bonding-tuned fracture resilience for robust biomechanical monitoring 被引量:2
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作者 Yizhuo Yang Wenjie Tang +13 位作者 Jinyi Wang Ruiqing Liu Ping Yang Shisheng Chen Yuehui Yuan jingfeng xu xueyang Ren Shancheng Yu Hao Wu Yunfan Zhou Leili Zhai Xiaodong Shao Zenan Chen Benhui Hu 《Science China Materials》 SCIE EI CAS CSCD 2022年第8期2289-2297,共9页
Recently,rapid advances in flexible strain sensors have broadened their application scenario in monitoring of various mechanophysiological signals.Among various strain sensors,the crack-based strain sensors have drawn... Recently,rapid advances in flexible strain sensors have broadened their application scenario in monitoring of various mechanophysiological signals.Among various strain sensors,the crack-based strain sensors have drawn increasing attention in monitoring subtle mechanical deformation due to their high sensitivity.However,early generation and rapid propagation of cracks in the conductive sensing layer result in a narrow working range,limiting their application in monitoring large biomechanical signals.Herein,we developed a stress-deconcentrated ultrasensitive strain(SDUS)sensor with ultrahigh sensitivity(gauge factor up to2.3×10^(6))and a wide working range(0%-50%)via incorporating notch-insensitive elastic substrate and microcrack-tunable conductive layer.Furthermore,the highly elastic amine-based polymer-modified polydimethylsiloxane substrate without obvious hysteresis endows our SDUS sensor with a rapid response time(2.33 ms)to external stimuli.The accurate detection of the radial pulse,joint motion,and vocal cord vibration proves the capability of SDUS sensor for healthcare monitoring and human-machine communications. 展开更多
关键词 flexible strain sensor MICROCRACK mechanophysiological signal monitoring ultrahigh sensitivity wide working range
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