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Research Progress on Solar Flare Forecast Methods Based on Data-driven Models
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作者 Ke Han Meng-Yao Yu +4 位作者 Jun-Feng Fu Wen-Bin Ling de-quan zheng Jie Wan Peng E 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第6期12-27,共16页
Eruption of solar flares is a complex nonlinear process,and the rays and high-energy particles generated by such an eruption are detrimental to the reliability of space-based or ground-based systems.So far,there are n... Eruption of solar flares is a complex nonlinear process,and the rays and high-energy particles generated by such an eruption are detrimental to the reliability of space-based or ground-based systems.So far,there are not reliable physical models to accurately account for the flare outburst mechanism,but a lot of data-driven models have been built to study a solar flare and forecast it.In the paper,the status of solar-flare forecasting is reviewed,with emphasis on the machine learning methods and data-processing techniques used in the models.At first,the essential forecast factors strongly relevant to solar flare outbursts,such as classification information of the sunspots and evolution pattern of the magnetic field,are reviewed and analyzed.Subsequently,methods of resampling for data preprocessing are introduced to solve the problems of class imbalance in the solar flare samples.Afterwards,typical model structures adopted for flare forecasting are reviewed from the aspects of the single and fusion models,and the forecast performances of the different models are analyzed.Finally,we herein summarize the current research on solar flare forecasting and outline its development trends. 展开更多
关键词 Sun:activity Sun:flares (Sun:)sunspots Sun:magnetic fields
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结肠息肉内镜下黏膜切除术后迟发性出血的危险因素分析 被引量:48
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作者 李永超 郑德权 +3 位作者 胡晓霞 刘海珊 黄婷婷 罗薇 《中国内镜杂志》 2020年第3期57-61,共5页
目的探讨行结肠息肉内镜下黏膜切除术(EMR)后发生迟发性出血的相关危险因素。方法回顾性分析2016年1月-2018年12月在该院行结肠息肉EMR治疗的328例患者的临床资料。以是否发生迟发性出血分为两组(出血组和未出血组),对比两组患者临床指... 目的探讨行结肠息肉内镜下黏膜切除术(EMR)后发生迟发性出血的相关危险因素。方法回顾性分析2016年1月-2018年12月在该院行结肠息肉EMR治疗的328例患者的临床资料。以是否发生迟发性出血分为两组(出血组和未出血组),对比两组患者临床指标的差异,采用Logistic回归模型分析EMR术后迟发性出血的独立危险因素。结果328例患者中发生术后迟发性出血22例(6.71%)。两组患者的年龄、高血压、肝硬化、抗凝药服用史、体质指数(BMI)、息肉大小、息肉形态和息肉数量比较,差异均有统计学意义(P<0.05);多因素Logistic回归分析显示,高血压、抗凝药服用史、息肉大小、息肉形态与迟发性出血发生存在密切关系(P<0.05)。结论结肠息肉患者合并高血压、长期服用抗凝药、息肉大小和息肉形态是发生EMR术后迟发性出血的独立危险因素。 展开更多
关键词 结肠息肉 内镜下黏膜切除术 迟发性出血 危险因素 LOGISTIC回归分析
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