中文题名: | 基于复杂网络的大气污染事件同步性研究 |
姓名: | |
保密级别: | 公开 |
论文语种: | 中文 |
学科代码: | 070201 |
学科专业: | |
学生类型: | 学士 |
学位: | 理学学士 |
学位年度: | 2021 |
学校: | 北京师范大学 |
校区: | |
学院: | |
第一导师姓名: | |
第一导师单位: | |
第二导师姓名: | |
提交日期: | 2021-06-14 |
答辩日期: | 2021-05-18 |
外文题名: | The event synchronization of air pollution based on complex network |
中文关键词: | |
外文关键词: | Smog ; PM2.5 ; Event Synchronization ; Complex Network ; Covid-19 |
中文摘要: |
雾霾污染问题存在着区域性和连通性的特征,具有错综复杂的时空结构,一直是危害人民健康和公共交通的环境问题。2020年初,一场突如其来的新冠疫情席卷全国,在此期间我国工业生产和社会生活的极大调整导致雾霾的时空结构出现大幅波动。本文使用中国环境监测总站的2024个站点的监测数据,从PM2.5浓度数值和雾霾网络性质的变化,以及连通子图的空间分布角度进行研究。发现我国近年来PM2.5平均浓度逐年下降,特别是疫情期间的污染情况明显减轻,日循环波动减缓。在使用复杂网络工具和非线性相关度量进行分析时,发现全国雾霾网络重要区域集中在华北平原附近,2020年相较往年出现了节点度、紧密中心性、集群系数下降,污染物长距离传输特性消退,孤立节点比例上升的特征。本文不仅为研究全国污染物关联网络的空间复杂性和时间演变性提供了见解,有助于我们可视化极端雾霾事件网络的结构,识别起关键作用的核心区域,还提出了基于复杂网络的大胆猜想来解释2020年春季雾霾时空结构大幅变化的原因:因受疫情影响,极端污染事件强度降低,污染物传输过程中消散速度快,进而导致远距离传输变弱,污染事件的局地性变强。最后本文绘制了空间子图分布,从网络分析的角度验证了该猜想。
﹀
|
外文摘要: |
This paper uses the data from 2024 monitoring stations of China Environmental Monitoring Station to study the changes in PM2.5 concentration and network properties, as well as the spatial distribution of subgraphs. It was found that the air pollution during the epidemic has been significantly reduced, and the daily cycles have slowed down. This paper uses complex network tools and nonlinear correlation measures for extreme air pollution events to analyze the whole smog network. It was found that important areas in the network were concentrated near the North China Plain, especially in the Hebei, Henan, Shandong, and Shanxi province. During the epidemic, the degree, close centrality, and cluster coefficient of each node in the network declined, and the number of subgraphs increases. The method proposed in this study not only provides insights for studying the spatial complexity and temporal evolution of the smog transmission network, helps us visualize the structure of the extreme smog event network, but also identifies the core that plays a key role in the network area. In addition, this study also proposed a bold conjecture based on the complex network to explain the reasons for the large changes in the temporal and spatial structure of the smog during the new crown epidemic.
﹀
|
参考文献总数: | 32 |
插图总数: | 20 |
插表总数: | 3 |
馆藏号: | 本070201/21053 |
开放日期: | 2022-06-14 |