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基于改进K-means聚类的在线新闻评论主题抽取 被引量:15
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作者 夏火松 李保国 杨培 《情报学报》 CSSCI 北大核心 2016年第1期55-65,共11页
新闻评论反映民众对新闻事件的观点,抽取评论主题,对用户、企业、政府都具有很高的情报分析价值。基于K-means聚类的主题挖掘算法应用到新闻评论中时,在欧氏距离下,如果使用最大距离法选初始点则会聚成一大类。为解决这个问题,论文首先... 新闻评论反映民众对新闻事件的观点,抽取评论主题,对用户、企业、政府都具有很高的情报分析价值。基于K-means聚类的主题挖掘算法应用到新闻评论中时,在欧氏距离下,如果使用最大距离法选初始点则会聚成一大类。为解决这个问题,论文首先在预处理阶段增加同义词替换和自动构建领域词典的部分,改善了数据稀疏性和高维性。其次,提出了K-means改进算法,用隐藏长评论-最大距离法选初始点,解决了初始点多为离群点的问题,用方差拐点确定K值,解决了预先设定聚类个数的问题,实验发现了先用BW权重选初始点,再用新提出的BW-DF权重聚类的效果最好。最后,将改进算法与原算法的聚类效果比较,实验结果表明,改进算法准确率高,抽取新闻评论主题的效果明显。 展开更多
关键词 在线新闻评论 K—means聚类改进 主题抽取 同义词替换 分词领域词典
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四维文档向量模型的k-means新闻文本聚类算法
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作者 高飞 鱼江 +2 位作者 任芳 黄保瑞 次旺多吉 《西藏大学学报(社会科学版)》 CSSCI 2013年第4期109-112,共4页
传统3DVM(3-Dimension Document Vector Model)由于没有使用新闻报道的时间因子,这使得该模型表示的新闻报道具有不准确性,进而影响新闻报道的聚类结果。本研究在三维文档向量模型的基础上加入了时间因子,提出了四维文档向量模型表示新... 传统3DVM(3-Dimension Document Vector Model)由于没有使用新闻报道的时间因子,这使得该模型表示的新闻报道具有不准确性,进而影响新闻报道的聚类结果。本研究在三维文档向量模型的基础上加入了时间因子,提出了四维文档向量模型表示新闻报道。最后,用k-means聚类算法进行新闻报道的的无监督聚类。实例验证结果表明本文提出的4DVM和k-means相结合的聚类算法优于3DVM以及VSM(vector space mode)和k-means相结合的聚类算法。 展开更多
关键词 4DVM 新闻文本 K-means聚类
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变译理论视角下的新闻标题汉译优化策略--基于越南《Vietnamplus电子报》的考察
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作者 刘云 陈氏碧叶 《汉江师范学院学报》 2024年第1期53-58,共6页
变译理论所述的变通手段对于新闻标题的汉译实践具有重要指导作用。基于越南《Vietnam-plus电子报》新闻标题汉译优化策略的考察表明,增补、删减、语序处理等相关变通手段的应用可有效达成标题信息的保真与识解,从而提高新闻语篇的传播... 变译理论所述的变通手段对于新闻标题的汉译实践具有重要指导作用。基于越南《Vietnam-plus电子报》新闻标题汉译优化策略的考察表明,增补、删减、语序处理等相关变通手段的应用可有效达成标题信息的保真与识解,从而提高新闻语篇的传播效能。 展开更多
关键词 变译理论 变通手段 越南《Vietnamplus电子报》 新闻标题汉译
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K-Means算法在气象新媒体产品热度上的应用研究
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作者 李亚玲 李涛 曹新彬 《大数据时代》 2018年第5期27-29,共3页
本文对气象新媒体中受众转发和评论里的关键词进行研究,运用k-means算法将这些关键词进行聚类,获取气象新媒体用户关心的关键词热度,从而为气象新媒体产品研发提供数据支撑。最后通过"川台天气"微博的产品热度分析验证该研究... 本文对气象新媒体中受众转发和评论里的关键词进行研究,运用k-means算法将这些关键词进行聚类,获取气象新媒体用户关心的关键词热度,从而为气象新媒体产品研发提供数据支撑。最后通过"川台天气"微博的产品热度分析验证该研究方法的可行性。 展开更多
关键词 气象新媒体 热度分析 聚类 K-means
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基于话题相似性改进的K-means新闻话题聚类 被引量:7
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作者 陈龙 徐建 +1 位作者 于亚男 胡建洪 《计算机与数字工程》 2017年第8期1560-1565,共6页
新闻话题聚类在舆情监督、热点话题发现、突发事件实时追踪等领域有着重要的应用。基于K-means的文本聚类算法由于算法简单易实现,时空复杂度低,聚类效果优异等特点被广泛用作新闻话题聚类算法。但传统的K-means算法又具有其局限性,如... 新闻话题聚类在舆情监督、热点话题发现、突发事件实时追踪等领域有着重要的应用。基于K-means的文本聚类算法由于算法简单易实现,时空复杂度低,聚类效果优异等特点被广泛用作新闻话题聚类算法。但传统的K-means算法又具有其局限性,如对初始中心点的选择敏感和用户必须自定义分组K等,导致算法收敛于局部最优而无法得到全局最优解。针对传统的K-means算法中初始聚类中心点随机选择导致聚类结果不稳定的问题,提出了一种改进的K-means算法用于新闻话题检测,该算法基于新闻报道相似性选择初始聚类中心点,保证各新闻话题集群具有很好的区分度。并在此基础上,根据新闻话题覆盖率自动确定话题集群个数K。实验结果表明,改进后的算法能够生成稳定的,高质量的话题集群。 展开更多
关键词 K-means算法 新闻话题检测 舆情监督 文本相似性 话题覆盖率
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基于改进K-means聚类方法的新零售物流配送路径优化 被引量:6
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作者 陈婵丽 钟映竑 《物流技术》 2019年第5期73-78,126,共7页
在新零售背景下,根据新零售的要求,从末端物流配送路径的角度出发,建立了车辆配送路径最优化数学模型,将遗传算法和K-means聚类算法进行结合与改进,对末端实体店配送方法进行优化。并以广州市天河区实际数据为例,通过Tensorflow软件仿... 在新零售背景下,根据新零售的要求,从末端物流配送路径的角度出发,建立了车辆配送路径最优化数学模型,将遗传算法和K-means聚类算法进行结合与改进,对末端实体店配送方法进行优化。并以广州市天河区实际数据为例,通过Tensorflow软件仿真实验进行验证。实验结果证明,和传统遗传算法相比,基于遗传算法改进的K-means聚类方法在复杂的区域物流内可配送路程,解决了重复配送路径问题,并且优化了物流配送路径,提高了配送效率,从而改善了服务质量和用户体验度,为新零售时代的物流配送提供路径优化方法。 展开更多
关键词 新零售 配送路径 遗传算法 K-means聚类算法 路径优化
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基于改进的K-means算法在高校学生消费数据中的应用 被引量:5
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作者 马幸飞 李引 《无锡商业职业技术学院学报》 2016年第6期82-85,共4页
校园一卡通系统作为数字化校园建设的重要组成部分,集多种功能为一体,并代替传统的消费管理模式,能更好处理噪声和孤立点。文章采用新距离标准的K-均值算法对学生三餐消费、商铺营业等情况进行聚类分析,并将结果应用于校内贫困生的评定... 校园一卡通系统作为数字化校园建设的重要组成部分,集多种功能为一体,并代替传统的消费管理模式,能更好处理噪声和孤立点。文章采用新距离标准的K-均值算法对学生三餐消费、商铺营业等情况进行聚类分析,并将结果应用于校内贫困生的评定工作及经营单位的产品、服务定位。 展开更多
关键词 校园一卡通 数据挖掘 聚类分析 新距离标准 K-均值算法
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An Exploratory Study of the Interpersonal Meanings of President Xi’s New Year Speech Based on Appraisal Theory
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作者 LIN Hanzhao 《Cultural and Religious Studies》 2023年第2期84-90,共7页
The research examines President Xi’s 2021 New Year speech with research questions centering around its abundant interpersonal meanings.Through qualitative content analysis,the research finds that it is typical for Ch... The research examines President Xi’s 2021 New Year speech with research questions centering around its abundant interpersonal meanings.Through qualitative content analysis,the research finds that it is typical for Chinese president to frequently use judgment and appreciation resources in reviewing the past year.Even in the face of the pandemic and natural disasters,the overall emotions of the speech remain positive,which corresponds to the forward-looking feature of New Year speech.Significance of the study abounds and future research can investigate how COVID-19 impacts the ideologies conveyed through political leaders’speeches through a comparative lens and how to produce more understandings that can help dismantle stereotypes and discrimination hidden in reports about COVID-19 by using Appraisal Theory critically,systematically,and comprehensively. 展开更多
关键词 Political discourse new Year speech Appraisal Theory Interpersonal meanings COVID-19 pandemic
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基于改进的k-means算法的新闻聚类的研究 被引量:1
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作者 唐啸虎 刘志锋 《电脑知识与技术》 2020年第10期201-203,217,共4页
针对k-means聚类算法对初始聚类中心敏感,容易陷入局部最优的情况,提出一种改进的基于k-means算法的新闻聚类方法.在用传统k-means算法对新闻数据集进行多次聚类的基础上,使用证据累积算法对k-means算法的聚类结果进行融合,以平滑k-mean... 针对k-means聚类算法对初始聚类中心敏感,容易陷入局部最优的情况,提出一种改进的基于k-means算法的新闻聚类方法.在用传统k-means算法对新闻数据集进行多次聚类的基础上,使用证据累积算法对k-means算法的聚类结果进行融合,以平滑k-means算法的结果,减少波动.实验结果表明提出的方法使聚类结果的准确率从53.33%提升至77.78%. 展开更多
关键词 K-means 新闻 聚类分析 融合 分级聚类
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基于改进K-means聚类算法在电力客户价值分群的应用 被引量:12
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作者 朱州 吴漾 《计算机与数字工程》 2017年第6期1049-1054,1149,共7页
针对电力客户特点实行不同的营销策略和提供差异化服务,就需要对电力客户做出准确的分群。传统K-means聚类算法对数据分布均匀的类似球形的数据集聚类效果比较好,一旦数据集分布密度不均衡,类簇大小差异明显时,传统K-means算法容易使稀... 针对电力客户特点实行不同的营销策略和提供差异化服务,就需要对电力客户做出准确的分群。传统K-means聚类算法对数据分布均匀的类似球形的数据集聚类效果比较好,一旦数据集分布密度不均衡,类簇大小差异明显时,传统K-means算法容易使稀疏的大类簇被高密度小类簇瓜分,导致电力客户分群正确率下降。论文基于电力客户数据分布不均衡的特点,采用了一种改进的K-means聚类算法。改进的K-means算法提出一个新的加权聚类准则,并根据该准则修改了聚类迭代过程。文章最后在对电力客户数据的分群聚类结果表明,改进的K-means聚类算法的分群聚类效果中各个群类的紧凑性得到有效提高,误分情况明显改善。 展开更多
关键词 K-means算法 新聚类准则 迭代权重 正确率 标准差
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互文性与新媒介环境下的文本生产--论东西的长篇小说《回响》
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作者 陈琪 《山东青年政治学院学报》 2024年第3期32-37,共6页
互文性连接了文本内外,东西小说《回响》的案情线与感情线将文本和此前与此后的社会事件文本联系在一起,文学与生活在虚构与现实中构成互文关系,文本意义得到丰富。小说文本与文学文本之间的互文是文本生产与解读的关键,其他文本依托互... 互文性连接了文本内外,东西小说《回响》的案情线与感情线将文本和此前与此后的社会事件文本联系在一起,文学与生活在虚构与现实中构成互文关系,文本意义得到丰富。小说文本与文学文本之间的互文是文本生产与解读的关键,其他文本依托互文进入关联文本,在全新的编织和结构下深化《回响》的写作意义。随着科技的发展,新媒介持续影响着文学写作,《回响》的创作与新媒介有着深度关联。新媒介环境下,文学影视化改编和读者阅读的介入不断与文学文本形成互文,为文本生产和意义生成提供了一种有益借鉴。 展开更多
关键词 《回响》 互文性 新媒介环境 文本意义
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基于K-means聚类的新建机场旅客吞吐量预测 被引量:1
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作者 刘科鸣 《山东交通科技》 2022年第5期9-12,共4页
以菏泽机场为例,通过K-means聚类分析,从与菏泽机场规模相近、所在城市大小相似的已通航机场中得到最合适目标,分别通过航空分担率与计量经济法预测菏泽机场短期旅客吞吐量,并通过2021年预测数据与真实数据的对比,验证方法的准确性。
关键词 机场吞吐量 K-means聚类 新建机场 预测
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The Nanjing International Symposium of New Frontiers in Cancer Research(Nov 9-10,2007) 被引量:1
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《Journal of Nanjing Medical University》 2007年第5期348-348,F0003,共2页
The Nanjing International Symposium of New Frontiers in Cancer Research will be held on Nov 9-10, 2007. The purpose of this symposium is to stimulate a dialogue among basic and clinical cancer researchers between Chin... The Nanjing International Symposium of New Frontiers in Cancer Research will be held on Nov 9-10, 2007. The purpose of this symposium is to stimulate a dialogue among basic and clinical cancer researchers between China and other countries to speed up translation of new findings in basic cancer biology into disease prevention, diagnosis, and treatment. We hope to use this conference as a forum to create a unique opportunity for exchange in current discoveries, fostering multidisciplinary collaborations, and identification of future opportunities in cancer treatment and patient care. There will be four sessions in this symposium: 展开更多
关键词 USA The Nanjing International Symposium of new Frontiers in Cancer Research Nov 9-10 2007
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Application of vertically integrated sampling approach to study of new production via ^(234)Th -^(238)U disequilibria 被引量:1
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作者 Chen Feizhou1 Huang Yipu2 Chen Min2 (1. College of Fishery Science, Shanghai Fisheries University, Shanghai 200090, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第2期37-44,共8页
The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in... The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~234Th/ ~238U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~234Th and the residence times for dissolved and particulate ~234Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(234)Th - ^(238)U disequilibria in large spatial scale. 展开更多
关键词 new production vertically integrated Sampling approach ^(234)Th - ^(238)U disequilibria Xia men Bay northern South China Sea
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A Three-Stage Stochastic Dynamic Pricing Game Model Affected by New Products into the Market
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作者 Waka Cheung Fang Chen 《Open Journal of Statistics》 2015年第4期284-290,共7页
In real-life marketing, a common phenomenon is that the prices of current product will have been cut down even the new product has not gone into market yet. Thus, it is very important for merchant to set the strategy ... In real-life marketing, a common phenomenon is that the prices of current product will have been cut down even the new product has not gone into market yet. Thus, it is very important for merchant to set the strategy which can make the excepted revenue maximum. So, this paper constructs a three-stage stochastic dynamic pricing game model for analyzing the influence of the uncertainty of entry timing of the new products on pricing of products being sold. By analyzing of the pricing strategy, there are big differences in the predictions of new product going into market between merchant and customers;the merchant will adopt cutting price for promotion strategy to reduce negative influence of the new products on the demand of the products sold now. Otherwise, the merchant will adopt the strategy of maximizing current period’s profit. 展开更多
关键词 STOCHASTIC Dynamic PRICING Game Model new Products ENTRY into MARKET Depreciate SALES PROMOTION means
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Treatment of Dyes Wastewater by a New Kind of Bio - Fluid Bed
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作者 黄永辉 奚旦立 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期120-122,共3页
A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing th... A new kind of bio-fluid bed used to treat dyes wastewater is described in detail due to its several special features,such as high removal efficiency,simple struc-ture,shock load resistance,etc.By means of analyzing the experiment data,the results show that the dye wastewater’s organic matter is removed greatly after be-ing treated by this new kind of bio-fluid bed.On the other hand,the removal efficiency of chromaticity of 展开更多
关键词 new BIO - fluid BED removal efficiency DYES wastewater.
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The Dimensions and Perceptual Meaning of Chinese New Year Painting as a Form of Visual Encirclement
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作者 Xiang Yunju Wu Lingwei 《Contemporary Social Sciences》 2017年第2期30-39,共10页
As mankind was one kind of aesthetic species,the visual study of Marxist philosophy has profound enlightenment in understanding the New Year paintings' visual meaning,form,development,cultivation,and features etc.... As mankind was one kind of aesthetic species,the visual study of Marxist philosophy has profound enlightenment in understanding the New Year paintings' visual meaning,form,development,cultivation,and features etc.In essence,Chinese folk New Year paintings is a visual expression,its nature of being pasted at home makes it a visual encirclement for the Chinese people,this vision encirclement in the home space gradually expands,constitutes a spiritual home with different cultural space,living environment,image schema,and secular and religious faith scope,in this visual encirclement,people's home life achieves the satisfaction,peace and self–comfort in diversity.The"childrenization"of New Year paintings reveals a close relationship between the immature of folk art and the original art as human childhood,and from the both aspects of form and content reflects the visual encirclement is actually a kind of siege with cultural significance,this siege has multiple levels in value ideas,historical tradition,ethical order and life knowledge,aesthetic taste and so on,makes us have a new aesthetic anthropology on the New Year paintings. 展开更多
关键词 new Year paintings visual encirclement perceptual meaning
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NEW SOLID BASE DERIVED FROM AIPO4-5 SUPPORTED KF
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作者 Jian Hua ZHU Qin Hug XU Hideshi HATTORI(Chemistry Department, Nanjing University.Nanjing 210093,China.)(Centre for Advanced Research of Energy Technology, Hokkaido University,Sapporo 060.Japan) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第7期671-674,共4页
Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the iso... Dispersion of KF on AlPO4-5 molecular sieve created basic sites and caused 1654 cm- band of bidentate carbonate in CO2 adsorption.After pre-treated above 823K. 5%KF/AlPO4-5exhibited basic catalytic activity in the isomerization of butenes at 273K. and the activity increasedwith the pre-treatment temperature up to 923K. 展开更多
关键词 new SOLID BASE DERIVED FROM AIPO4-5 SUPPORTED KF
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Asymmetric Mean Annual Temperature Wavelets Surface Air Layer of Berlin for 1701-2021
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作者 Peter Mazurkin 《Journal of Atmospheric Science Research》 2022年第3期1-9,共9页
The regularities of the dynamics of the average annual temperature of Ber­lin from 1701 to 2021 are revealed.A total of 65 wavelets were received.The temperature has a high quantum certainty,and the change in the... The regularities of the dynamics of the average annual temperature of Ber­lin from 1701 to 2021 are revealed.A total of 65 wavelets were received.The temperature has a high quantum certainty,and the change in the aver­age annual temperature of Berlin was identified by a model that contains only two components for prediction.The basis of the forecast at 320 years makes it possible to look into the future until the year 2340.The forecast confirms the conclusions made in the CMIP5 report on global warming.With an increase in the number of components in the model up to five,the forecast is possible only until 2060.Therefore,the model with only two components is workable.The trend is characterized by a modified Man­delbrot equation showing exponential growth with a high growth rate of 1.47421.The wave equation also has an amplitude in the form of the Man­delbrot law(in mathematics,the Laplace law,in biology,the Zipf-Pearl law,in econometrics,the Pareto law),when the exponential growth activity is equal to 1.For 1701,the period of oscillation was 2×60.33333≈120.7 years.By 2021,the period decreased and became equal to 87.6 years.The trend is such that by 2340 the period of oscillation will decrease to 30.2 years.Such an increase in fluctuations indicates an imbalance in climate disturbances in temperature in Berlin.For Berlin,the last three years are characterized by sharp decreases in the average annual temperature from 11.8℃ to 10.5℃,i.e.by 12.4% in 2021.Therefore,the forecast is still unstable,as a further decrease in the average annual temperature of Berlin in the near future may change the picture of the forecast. 展开更多
关键词 Berlin mean annual temperature 1701-2021 WAVELETS FORECAST
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Wave Dynamics of the Average Annual Temperature Surface Air Layer New Delhi for 1931-2021
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作者 Peter Mazurkin 《Journal of Atmospheric Science Research》 2022年第2期52-66,共15页
The identification method revealed asymmetric fluctuations in the dynamics of the average annual temperature in New Delhi from 1931 to 2021,that is,for 90 years.An analysis of the wave patterns of climate until 2110 w... The identification method revealed asymmetric fluctuations in the dynamics of the average annual temperature in New Delhi from 1931 to 2021,that is,for 90 years.An analysis of the wave patterns of climate until 2110 was carried out.Geotechnology of the Himalayan passage was proposed to reduce heat waves in India and China.Formulas containing four and 18 fluctuations were adopted for forecasting.Models give an increase in the heat wave from 2021,which is the fourth component.As a result,the landscape of the Himalayan mountains and the deserts of Thar and Takla Makan create a regional climate system that is original for the land of the Earth.In this system,oscillatory temperature adaptation in the future will be several times greater than the global warming rate predicted in the IPCC CMIP5 report.Between 2001 and 2019 the largest temperature increase wave maximum was observed in New Delhi at 0.65℃ in 2012-2013.In the sixth phase from 2036 to 2049,an ecological catastrophe will break out in New Delhi.According to calculations,the maximum value of the average annual temperature in New Delhi was 25.82℃ in 2017.Since then,the cooling has continued for four years,which will continue until 2028.The temperature will drop to 22.54℃ due to a change in solar activity by 3.28℃.Then by 2044,the average annual temperature in New Delhi will increase to 31.03℃,or the increment will be 31.03-22.54=8.49℃.In 2035,the climate in New Delhi will become hotter compared to 2021.The increase in the heat wave is noticeable.From 1931 to 2049 there will be six half-periods of cooling and warming:1)23;2)23;3)20;4)18;5)15;6)13 years old.The most dangerous is the sixth stage.It is proposed at the fifth stage for 15 years until 2037 in northern India to the Takla Makan desert in China to build a passage up to 350 km long,10 km-20 km wide and at least 4.5 km high. 展开更多
关键词 new Delhi Temperature 1931-2021 Critical wavelet Forecasts
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