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Distribution Characteristics of Ozone and the Relationship with Typhoon Processes in the Northwest Pacific Ocean

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Meteorological and Environmental Research 2023年第3期14卷 37-44页

作者： Li CHEN shichang guo Ting HU Yunfeng GAO Lijiang Sanyi Airport of Yunnan Airport Group Limited Liability Company Lijiang 674100China Yunnan University Kunming 650091China Guangzhou Meteorological Bureau Guangzhou 511430China

Based on the vertical ozone reanalysis data and total ozone column data derived from the European Centre for Medium-Range Weather Forecasts,the spatial and temporal distribution characteristics of ozone on each isobaric surface in the troposphere over the Northwest Pacific Ocean were analyzed,and the backward trajectory method was used to track the influence of typhoon on the distribution of *** results show that the updraft near the typhoon center transported the air with low O_(3)content in the lower layer to the upper layer,which reduced O_(3)content in the upper layer and formed a low-value area of O_(3).The variation trend of total ozone column in the regions where typhoons"Megi"and"Fengshen"occurred was analyzed by the case analysis *** is found that there was a low-value area of total ozone column anomaly near the typhoon center,and there was a certain correlation between typhoon intensity PDI and total ozone column anomaly at the development and maturity stages of typhoons.

关键词： Ozone mass mixing ratio Typhoon Total ozone column Backword trajectory method

Interannual Variation of the Onset of Yunnan’s Rainy Season and Its Relationships with the Arctic Oscillation of the Preceding Winter

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Atmospheric and Climate Sciences 2017年第2期7卷 210-222页

作者： Yan Chen shichang guo Yu Liu Jianhua Ju Juzhang Ren Yunnan Institute of Meteorological Sciences Kunming China Department of Atmospheric Sciences Yunnan University Kunming China Yunnan Climate Center Kunming China

Based on an analysis of the circulation in May associated with the interannual variation of the onset of Yunnan’s rainy season, this study examined the rela-tionship between Arctic Oscillation (AO) and the onset timing of the rainy sea-son by using the NCEP/NCAR reanalysis and observational precipitation data for 1961-2010. The results indicated that, on an interannual time scale, intense Asian summer monsoon and an active EU-pattern wave train circulation in its positive phase, associated with a cold cyclonic cell covering the western part of the East Asian subtropical westerly jet (EASWJ), jointly contributed to the onset of the rainy season in May. Otherwise, the onset might be suppressed. The cold cyclonic cell over East Asia likely led to the southward shift and enhancement of EASWJ as well as its secondary circulation around the jet entrance, which could provide a favorable dynamic and thermal condition for rainfalls in Yunnan as was revealed in previous studies on 10 - 30-day time scale. Further examination showed that the preceding wintertime AO played a significant role in the timing of the onset of the rainy season before the mid-1980s’ by mostly modulating the wave-train-like circulation over East Asia in May. During that time period, when the AO index of the previous winter was positive (negative), Yunnan’s rainy season tended to begin earlier (later) than normal. Correspond-ingly, the precipitation in May was also closely linked to wintertime AO.

关键词： Onset of Yunnan’s Rainy Season East Asian Subtropical Westerly Jet (EASWJ) Arctic Oscillation (AO) Interannual Variation

Spatial and temporal distribution of storms and their activities over the Bay of Bengal

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Research in Cold and Arid Regions 2009年第5期1卷 448-457页

作者： Xu Duan Yun Tao CanQiong Cun shichang guo LinYi LV Meteorological Institute of Yunnan Province Kunming Yunnan 650034 China Meteorological Observatory of Dehong Prefecture in Yunnan Province Luxi Yunnan 678400 China Atmospheric Science Department of Yunnan University Kunming Yunnan 650091 China

By statistically analyzing the storm data from the Joint Typhoon Warning Center(JTWC) over the Bengal Bay during the period 1945-2006,it is found that the yearly averaged tropical cyclone(TC) number over the Bay of Bengal is 8.12,which takes place in any month of the whole year;February and March have the fewest TC *** TC numbers begin to increase starting in April and arrive at a peak in *** from TC over the Bay of Bengal,the tropical storms(TS) over the Bay of Bengal has two peak periods,appear in May and in October or November,*** regard to TS intensity,the super severe storm of H4 criterion appeared only one time during the period 1971-1986,but appeared eight times during the period *** monthly change of the original position,the averaged maintaining time,and the longest maintaining time of TS also have two peak values:They appear in April or May and in October or November,*** peak value of the original position in October or November is bigger than that in April or *** peak value of the average maintaining time and the longest main-taining time of the TS in April or May is bigger than that in October or *** landfall path is mostly moving toward northwest or west and accounts for 56.7 *** landfall path of the TS differs from that of TC in some *** main difference is that the numbers of the northwestern path and un-landfall of TS are less than those for TC,and the numbers of the western path and northeastern path of TS are greater than for *** of the landfall TS in the north-east path has a peak,it and the beginning of the rainy season in Yunnan Province are closely related;it is on Yunnan Province's early summer precipita-tion that they have a great impact.

关键词： storm over the Bay of Bengal the temporal and spatial distribution statistically characteristic TC or TS landfall

ENSO循环对东亚地区平流层臭氧分布的影响

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高原气象 2017年第3期36卷 865-874页

作者：汪明圣郭世昌云南大学大气科学系昆明650091 广东省气候中心广州510610

采用NOAA提供的ONI(Oceanic Nio Index)指数资料与欧洲中心提供的臭氧再分析资料,以滞后相关为切入点,分析了ENSO循环对东亚地区平流层臭氧分布的影响,探讨了ENSO不同位相(El Nio、La Nia)对臭氧场的强迫影响程度,并且用ENSO对剩... 详细信息

采用NOAA提供的ONI(Oceanic Nio Index)指数资料与欧洲中心提供的臭氧再分析资料,以滞后相关为切入点,分析了ENSO循环对东亚地区平流层臭氧分布的影响,探讨了ENSO不同位相(El Nio、La Nia)对臭氧场的强迫影响程度,并且用ENSO对剩余环流的影响解释了平流层臭氧变化的动力机制。结果表明:(1)ENSO对东亚地区平流层臭氧的分布有明显的影响,在平流层30 h Pa和70 h Pa尤为显著,且滞后8个月时二者相关达到最大;(2)El Nio发生8个月后中纬度地区平流层30 h Pa的臭氧有所减少,而高纬度臭氧增加,70 h Pa则与之相反,同时在低纬度地区70 h Pa臭氧减少;La Nia反之;(3)Nio3.4区海温与滞后8个月臭氧的SVD分析结果也有类似的变化;(4)El Nio和La Nia的影响之间有显著的差异,在分别滞后于El Nio和La Nia事件8个月后平流层低层的臭氧含量差异可达-25%以上。(5)ENSO可以通过影响剩余环流的变化,进而影响臭氧分布发生以上的变化。

关键词： ONI ENSO 滞后相关平流层臭氧剩余环流

INPUT COUPLER FOR Ka BAND TE021 CIRCULAR ELECTRIC MODE OPERATION IN A GYROKLYSTRON AMPLIFIER

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Journal of Electronics(China) 2003年第6期20卷 472-476页

作者： Zhu Min Luo Jirun Luan Yuantao guo Wei Zhang shichang Wu Ersheng guo Hezhong(Institute of Electronics, Chinese Academy of Sciences, Beijing 100080) Institute of Electronics Chinese Academy of Sciences Beijing

An input coupler for the TE021 circular electric mode in a gyroklystron amplifier through using TE811 as a transition coupling mode in a coaxial cavity has been proposed and numerically simulated in a frequency range of Ka-Band with HFSS code. The coupling efficiency of the TE021 mode and the suppression for the TE811 mode in the main cylindrical cavity are deliberately considered by adjusting the position and size of coupling holes as well as the radius of the drift tubes. The numerical results show that the TE21 mode can successfully be excited, and rational coupling efficiency and high mode purity for the TE021 mode in the cylindrical cavity can be reached for the engineering application of gyroklystron amplifier study.

关键词： Coaxial cavity Cylindrical cavity Gyroklystron amplifier Input coupler

北半球中高纬地区冬季大气臭氧与极涡强度关系

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高原气象 2016年第5期35卷 1290-1297页

作者：黎成超郭世昌易琦黎海凤云南省气象局昆明650034 云南大学大气科学系昆明650091

为全面了解冬季北半球中高纬度地区臭氧与同期北极极涡强度变化的相关关系,利用1979年1月至2011年12月欧洲中心再分析资料,选取了4个关键区(北极、东亚、北美和西欧),采用相关分析和E-P通量计算方法,分析了两者之间的相关关系并进行了... 详细信息

为全面了解冬季北半球中高纬度地区臭氧与同期北极极涡强度变化的相关关系,利用1979年1月至2011年12月欧洲中心再分析资料,选取了4个关键区(北极、东亚、北美和西欧),采用相关分析和E-P通量计算方法,分析了两者之间的相关关系并进行了机制研究。结果表明:(1)冬季北极平流层臭氧总量与极涡强度的负相关关系较好;(2)当极涡强(弱)年,极圈内和外围的北美部分地区臭氧总量显著减少(增加);(3)极涡强度弱时,上传到平流层的涡动热通量强,北半球中高纬地区E-P通量散度辐合增强,剩余环流加强,将导致该地区得到低纬高浓度臭氧的补充而使得臭氧含量增多;(4)1979-2011年上传到中高纬平流层的波动通量增加,造成极区温度增加,进而抑制非均相反应发生而使得极区臭氧含量增加。

关键词：关键区臭氧极涡强度 E—P通量涡动热通量

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基于红外热像的瓷绝缘子污秽等级检测方法

农业工程学报 2016年第15期32卷 175-181,F0003页

作者：房俊龙王金霞杨柳王冠男韩佳宁郭士昌东北农业大学电气与信息学院哈尔滨150030

为解决目前绝缘子污秽等级检测方法操作繁琐、漏判率高的问题,提出了一种基于红外热像处理的瓷绝缘子污秽等级检测方法。首先,将现场拍摄的绝缘子红外热像图进行二步法去噪;然后,针对绝缘子红外热像的颜色特征,采用RGB图像中的R分量图... 详细信息

为解决目前绝缘子污秽等级检测方法操作繁琐、漏判率高的问题,提出了一种基于红外热像处理的瓷绝缘子污秽等级检测方法。首先,将现场拍摄的绝缘子红外热像图进行二步法去噪;然后,针对绝缘子红外热像的颜色特征,采用RGB图像中的R分量图以及改进的OTSU分割算法获取二值图像,再对二值图像进行两次数学形态学修正,得到绝缘子积污区域。利用统计学方法提取积污区域R通道的5个特征分量,并对BP神经网络进行训练,建立绝缘子污秽等级判别网络。选取5个污秽等级的XP-70瓷绝缘子红外热像图共500组作为试验样本,对该系统进行反复测试,总识别精度达到91%以上。

关键词：瓷神经网络算法绝缘子污秽等级红外热像

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单晶SiC微纳米压痕的力学行为及仿真分析

压电与声光 2018年第5期40卷 742-745页

作者：张银霞郭世昌郜伟王栋王健康郑州大学机械工程学院河南郑州450001

为了研究单晶SiC的微观力学性能和加工方式,开展了单晶6H-SiC(0001)的微纳米压痕试验,并采用ABAQUS软件对纳米压痕过程进行了数值仿真及完成了试验验证。结果表明,单晶SiC在加载阶段的变形机理与压入载荷无关;硬度和弹性模量表现出了明... 详细信息

为了研究单晶SiC的微观力学性能和加工方式,开展了单晶6H-SiC(0001)的微纳米压痕试验,并采用ABAQUS软件对纳米压痕过程进行了数值仿真及完成了试验验证。结果表明,单晶SiC在加载阶段的变形机理与压入载荷无关;硬度和弹性模量表现出了明显的尺寸效应;球形压头作用下的应力值最小,玻氏压头和维氏压头作用下的应力值相同,大于圆锥压头的应力值;压痕裂纹类型有主裂纹、侧向裂纹、主次型裂纹、平直型裂纹、间断型裂纹,裂纹的平均长度随着加载力的增加而逐渐增加。

关键词：单晶SiC 尺寸效应压痕仿真显微硬度微裂纹

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“大气动力学基础”课程教学经验谈

高等理科教育 2009年第2期 112-114页

作者：郭世昌常有礼云南大学资源环境与地球科学学院

文章探讨了“大气动力学基础”课程的教学经验，通过建立试题库、教考分离、多媒体教学、培养教学骨干、强化助教辅导、补充教学内容以及培养良好学风等几方面，实施了一系列的改革措施，并取得了显著的成效。

关键词：大气动力学基础教学改革