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中文文本蕴含气象灾害事件信息多模型融合抽取方法 被引量:4
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作者 胡段牧 袁武 +2 位作者 牛方曲 袁文 韩嫒嫒 《地球信息科学学报》 CSCD 北大核心 2022年第12期2342-2355,共14页
随着气候变暖加剧,全球极端天气事件频发,重大气象灾害的发生频率与日俱增。研究气候变化与气象灾害发生频率的关系,对于气候变化背景下的防灾减灾具有重要意义。文献资料及泛在网络数据中蕴含了海量的气象灾害时空事件,为此,本文基于... 随着气候变暖加剧,全球极端天气事件频发,重大气象灾害的发生频率与日俱增。研究气候变化与气象灾害发生频率的关系,对于气候变化背景下的防灾减灾具有重要意义。文献资料及泛在网络数据中蕴含了海量的气象灾害时空事件,为此,本文基于自然语言处理技术研发了文本气象灾害时空事件自动抽取方法。(1)提出了基于专业文献的由粗到精的气象灾害标注语料训练库构建方法。首先针对不同文献资料存在的歧义和不兼容等问题,构建了面向文本事件统一的气象灾害知识体系。然后构建了基于章节结构的粗标注方法,分别针对长文本(现代文)和短文本(文言文)研发了基于Labeled LDA模型及基于TF-IDF和N-gram模型的精细标注语料筛选方法,解决了语料库的快速构建问题;(2)基于BERT-CNN模型研发了融合上下文语义特征和多粒度的局部语义特征的、面向长短文本一体化处理的气象灾害时空事件自动分类方法;(3)利用该方法分别从文言文和泛在网络数据中自动抽取了灾害时空事件,其宏F1值分别达到89.09%和80.06%,主要气象灾害时空事件分布与专业统计数据相关性较高;(4)基于以上结果,重建了我国各历史时期灾害时空演变过程,发现各时期灾害数据量整体呈现出逐步上升趋势,暴雨灾害、洪涝灾害与干旱灾害是影响我国的主要灾种。本方法既可实现网络长文本事件的自动发现,也可实现文言文短文本事件的自动检测,为文本数据便捷应用于气象灾害研究和监测提供了新的技术方法。 展开更多
关键词 气象灾害 时空事件 知识体系 语料库 文本分类 BERT-CNN模型 事件抽取
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Spatio-temporal evolution and influencing factors of geopolitical relations among Arctic countries based on news big data
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作者 LI Meng YUAN Wen +3 位作者 YUAN Wu NIU Fangqu LI Hanqin hu duanmu 《Journal of Geographical Sciences》 SCIE CSCD 2022年第10期2036-2052,共17页
Global warming has caused the Arctic Ocean ice cover to shrink.This endangers the environment but has made traversing the Arctic channel possible.Therefore,the strategic position of the Arctic has been significantly i... Global warming has caused the Arctic Ocean ice cover to shrink.This endangers the environment but has made traversing the Arctic channel possible.Therefore,the strategic position of the Arctic has been significantly improved.As a near-Arctic country,China has formulated relevant policies that will be directly impacted by changes in the international relations between the eight Arctic countries(regions).A comprehensive and real-time analysis of the various characteristics of the Arctic geographical relationship is required in China,which helps formulate political,economic,and diplomatic countermeasures.Massive global real-time open databases provide news data from major media in various countries.This makes it possible to monitor geographical relationships in real-time.This paper explores key elements of the social development of eight Arctic countries(regions)over 2013-2019 based on the GDELT database and the method of labeled latent Dirichlet allocation.This paper also constructs the national interaction network and identifies the evolution pattern for the relationships between Arctic countries(regions).The following conclusions are drawn.(1)Arctic news hotspot is now focusing on climate change/ice cap melting which is becoming the main driving factor for changes in geographical relationships in the Arctic.(2)There is a strong correlation between the number of news pieces about ice cap melting and the sea ice area.(3)With the melting of the ice caps,the social,economic,and military activities in the Arctic have been booming,and the competition for dominance is becoming increasingly fierce.In general,there is a pattern of domination by Russia and Canada. 展开更多
关键词 ARCTIC geographical relationship spatiotemporal data mining topic model interactive network big data
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