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动力修正式配气凸轮的计算机辅助设计
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作者 孙红霞 《中国制造业信息化(学术版)》 2003年第12期105-107,共3页
在高速凸轮机构动态数学模型的基础上 ,对应用广泛的动力修正式凸轮的计算机辅助设计进行了探讨。利用MATLAB语言 ,结合具体实例进行了动力修正式凸轮的动力学计算及凸轮轮廓曲线的设计 。
关键词 动力正式配凸轮 计算机辅助设计 动态数学模型 MATLAB语言 内燃机
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用于气候研究的雪盖模型参数化方案敏感性研究 被引量:12
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作者 孙菽芬 李敬阳 《大气科学》 CSCD 北大核心 2002年第4期558-576,共19页
为了得到一个适用于气候研究简化的季节性雪盖模式最佳方案,必须对雪盖内部的重要物理过程、其与上大气相互作用、相应模型的参数化方案和有关的参数选取以及模型的分层结构进行深入研究。利用作者的雪盖模型(SAST),对其中的一些关键性... 为了得到一个适用于气候研究简化的季节性雪盖模式最佳方案,必须对雪盖内部的重要物理过程、其与上大气相互作用、相应模型的参数化方案和有关的参数选取以及模型的分层结构进行深入研究。利用作者的雪盖模型(SAST),对其中的一些关键性过程的有关参数化方案(如压实、相变、融化雪水流动及分层方案考虑等)及关键的参数(如雪面反照率、有效热传导系数及持水能力等)进行了分析和敏感性试验,得到若干有意义的结论,为雪盖模式改进提供有用的结论。 展开更多
关键词 气修 雪盖模型 参数化方案 敏感性试验
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热防护服的微气候冷却系统综述 被引量:3
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作者 张富丽 《中国个体防护装备》 2002年第3期29-30,共2页
微气候冷却系统(Microclimate Cooling System,MCS)是高温湿热环境中,穿着密闭式防护服工作人员必备的服装系统,其主要功能是吸收人体的热负荷,维持体心温度的恒定,减少热损伤,以提高人体在高热环境中的工作效率,延长工作时间.
关键词 热防护服 气修冷却系统 综述
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西太平洋航线温带爆发性气旋活动与天气海况分析 被引量:1
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作者 夏良云 黄立文 《武汉理工大学学报(交通科学与工程版)》 北大核心 2001年第1期79-82,共4页
根据观测统计和天气海洋资料 ,分析了西太平洋航线温带爆发性气旋活动的气候学特征 ,并结合个例考查了爆发性气旋的天气与海况特点 .结果表明爆发性气旋具有不同于一般气旋活动的规律和天气海况特征 ,认识它们有助于减少或避免海损事故... 根据观测统计和天气海洋资料 ,分析了西太平洋航线温带爆发性气旋活动的气候学特征 ,并结合个例考查了爆发性气旋的天气与海况特点 .结果表明爆发性气旋具有不同于一般气旋活动的规律和天气海况特征 ,认识它们有助于减少或避免海损事故的发生 . 展开更多
关键词 爆发性 气修特征 海况 西太平洋航线 温带 海损事故
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一种降低喷气织机用钢筘气流损耗的方法 被引量:2
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作者 由学志 由希雨 周家骧 《纺织器材》 2005年第2期20-22,共3页
介绍了便携式气流损耗仪和气槽修整机的结构、原理及其使用方法,说明使用该仪器和气槽修整机能有效降低喷气织机用钢筘气流的损耗。
关键词 织机 钢筘 流损耗 检测仪 整机
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广东省气候生态环境监测总体构思
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作者 丘振中 杜尧东 《辽宁气象》 2005年第1期18-19,共2页
根据广东省自然地理、生态环境现状以及气象部门自身的特点 ,从主要生态系统监测、主要生态环境问题监测、气候变化主导因子及气候圈层间相互作用过程监测等 3方面 ,提出了构建广东省气象部门生态环境监测的内容及观测站网布局。
关键词 象部门 候生态环境 候变化 圈层 气修 自然地理 观测站 总体构思 主导因子 广东省
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关于海洋石油液气分离器的检测与评判
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作者 刘金玲 《中国设备工程》 2023年第20期193-195,共3页
本文以某海洋石油液气分离器为例,探究海洋石油液气分离器的检测与评判。所做研究基于海洋石油液气分离器的工作原理和检测现状,提出一种基于X射线、图片纹理特征和超声波的检测方法,并论述不同检测技术的评判标准。所提方法科学且完善... 本文以某海洋石油液气分离器为例,探究海洋石油液气分离器的检测与评判。所做研究基于海洋石油液气分离器的工作原理和检测现状,提出一种基于X射线、图片纹理特征和超声波的检测方法,并论述不同检测技术的评判标准。所提方法科学且完善,能够最大限度地实现海洋石油液气分离器的检测验收,对于判断海洋石油液气分离器的安全情况,十分有效。 展开更多
关键词 海洋钻井 机液分离器 故障检测 评判标准
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河西走廊花海剖面晚冰期以来年代学及沉积特征研究 被引量:13
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作者 王乃昂 李卓仑 +1 位作者 李育 朱金峰 《沉积学报》 CAS CSCD 北大核心 2011年第3期552-560,共9页
选择位于河西走廊的花海古湖泊沉积剖面作为研究对象,根据13个普通14C和5个AMS14C年代结果,以沉积物岩性特征为主要指标,建立了晚冰期以来花海湖泊沉积的年代框架及环境变化过程。结果表明:花海地区新仙女木期和晚冰期花海湖泊主要以芒... 选择位于河西走廊的花海古湖泊沉积剖面作为研究对象,根据13个普通14C和5个AMS14C年代结果,以沉积物岩性特征为主要指标,建立了晚冰期以来花海湖泊沉积的年代框架及环境变化过程。结果表明:花海地区新仙女木期和晚冰期花海湖泊主要以芒硝沉积为主,指示了较低的温度环境。芒硝沉积中的淤泥细线为短暂升温标志,芒硝-淤泥-芒硝的沉积韵律揭示了晚冰期和新仙女木期气候的不稳定性和温度的周期性变化。根据沉积过程和岩性特征,全新世花海湖泊在千年尺度上存在干湿变化特征。10.47cal ka BP之前的早全新世气候较为干旱,以冲洪积和风成砂为主的沉积过程,10.47~8.87cal ka BP的早全新世湖相沉积所揭示的气候由干到湿的转变期,8.87~5.5cal ka BP存在深湖相沉积的气候湿润期,5.5cal ka BP至今沉积间断所揭示的中晚全新世气候呈现干旱化趋势,湖泊趋于萎缩干涸。 展开更多
关键词 晚冰期 新仙女木气修事件 年代学 河西走廊 花海
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祁连山高寒牧区甘肃马鹿产茸量的分析 被引量:10
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作者 侯扶江 安玉峰 《中国农业科学》 CAS CSCD 北大核心 2002年第10期1269-1274,共6页
对祁连山北坡高寒牧区放牧甘肃马鹿产茸情况的分析表明 ,甘肃马鹿的鲜茸单产随年龄增长逐渐增加 ,11岁产茸量最高 ,此后产茸量下降。甘肃马鹿茸根围、眉枝长、冰枝基围、冰枝长、中枝长、中枝至茸端的距离等 6个茸尺性状与茸干重呈显著... 对祁连山北坡高寒牧区放牧甘肃马鹿产茸情况的分析表明 ,甘肃马鹿的鲜茸单产随年龄增长逐渐增加 ,11岁产茸量最高 ,此后产茸量下降。甘肃马鹿茸根围、眉枝长、冰枝基围、冰枝长、中枝长、中枝至茸端的距离等 6个茸尺性状与茸干重呈显著正相关 ,采用眉枝长、冰枝长和中枝长 3个性状建立综合评定指数 ,可有效评价该马鹿产茸量。灰色关联分析显示 ,各气候因子在不同季节对产茸的影响有所差异 ,其中 5~ 6月是气候因素影响当年产茸量的关键时期 ,这一时期日照时数对当年鹿茸产量影响最大 ,总体而言气温与鹿茸产量的关系最为密切。 4岁马鹿的产茸量与上一年平均气温呈显著负相关 ,甘肃马鹿鹿群数量与产茸量之间呈线性正相关 ,可用于该鹿场产茸量预测。肃南鹿场现有甘肃马鹿鹿群及鹿茸的增加空间有限 。 展开更多
关键词 甘肃马鹿 产茸量 气修 鹿群规模 祁连山高寒牧区
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发展方程计算稳定性的比较分析 被引量:1
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作者 林万涛 季仲贞 杨晓忠 《气候与环境研究》 CSCD 2001年第1期77-83,共7页
针对线性与非线性发展方程的几种差分格式,以一维线性和非线性平流方程为例,对线性与非线性发展方程差分格式的计算稳定性进行了比较分析,揭示了差分格式结构和初值形式与非线性计算稳定性的关系。
关键词 发展方程 差分格式 计算稳定性 初值 平流方程 气修数值模拟
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A comprehensive review of carbon sequestration of seagrass in China from 2013
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作者 HUANG Xiaotong 《Marine Science Bulletin》 2024年第1期31-41,共11页
Seagrass is not only known for its ecological role,but also for its high capacity on the carbon sequestration.Although the area of seagrass meadows was less than 0.2%of the world’s oceans,the yearly organic carbon bu... Seagrass is not only known for its ecological role,but also for its high capacity on the carbon sequestration.Although the area of seagrass meadows was less than 0.2%of the world’s oceans,the yearly organic carbon burial of seagrass reached 10%of that in the ocean.Anthropogenic activities in the past two decades and the climate change have led to a significant decrease of seagrass meadow.Since seagrass is widely distributed along the coastline of China,it is necessary to put more efforts on the seagrass conservation and restoration,which will consequently be a suitable nature based solution for mitigating the climate change.This paper provides a comprehensive review on the following five aspects:1)the seagrass distribution in China;2)the role that seagrass plays in the climate mitigation;3)carbon sequestration of seagrass in China;4)loss of seagrass habitats and 5)the restoration of seagrass habitat in China since 2013.Current research gap and prospective research direction were also pointed out in this study. 展开更多
关键词 SEAGRASS carbon sequestration climate mitigation RESTORATION DISTRIBUTION ecological role
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中国污水治理的一个新思考 被引量:3
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作者 钟国勇 《环境污染治理技术与设备》 CSCD 北大核心 2002年第12期96-98,共3页
本文通过对中国地形及气候特征的讨论 ,提出沙漠治水 ,水治沙漠的观点 ,为中国及其他国家的污水治理 。
关键词 中国 污水治理 污水西调工程 沙漠 蒸发 环流 降水 气修
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Study on Eco-restoration of Polluted Rivers 被引量:1
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作者 万玉山 邹涛 +1 位作者 邵敏 李定龙 《Agricultural Science & Technology》 CAS 2016年第10期2386-2389,2409,共5页
[Objective] This study was conducted to find a restoration method suitable for urban polluted rivers. [Method] A segment of a representative river in the old part of a certain city in south Jiangsu was selected as a r... [Objective] This study was conducted to find a restoration method suitable for urban polluted rivers. [Method] A segment of a representative river in the old part of a certain city in south Jiangsu was selected as a research area through previous investigation, and the polluted river was cleaned and restored by 3 methods, i.e. artificial wetland, floating island type wetland and purification floating island. [Resuit] Floating plants (Hydrocotyle verticillata and Myriophyllum spicatum) showed better restoration effects than emergent aquatic plants (Iris wilsonii, Arundo donax, reed, water-cultured Ilex chinensis and Lythrum salicaria). The two types of plants showed the removal rates of total nitrogen of 37.9% and 34.1%, respectively, the removal rates of total phosphorous of 80.1% and 73.5%, respectively, the removal rates of COD of 81.1% and 74.8%, respectively, the removal rates of ammonia nitrogen of 80.6% and 85.9%, respectively, and the removal rates of SS of 59.1% and 77.3%, respectively. Among the purification floating island, the artificial wetland and the floating island type wetland, the purification floating land restoration technique exhibited the best removal effect, with the removal rates of 87.6%, 71.3%, 87.6%, 97.5% and 81.8% for total nitrogen, total phosphorous, ammonia nitrogen COD and SS, respectively. The nitrification and denitdfication rates of bottom mud and water samples in the engineering segment were remarkably higher than those in the reference segment, by 15.4% and 21.1%, respectively. The nitrification and denitrification rates of bottom mud in the engineering segment and the non-engineering segment were higher than those of water samples by 26.9% and 31.8%, respectively. Restoration plants showed better removal effects of total phosphorous, total nitrogen, COD and SS under aeration condition than noeration condition. [Conclusion] The purification floating island has a significant restoration effect on urban polluted river. 展开更多
关键词 Polluted Rivers Eco-restoration AERATION
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大棚黄瓜早期定植试验研究获得成功
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作者 施振东 边振有 《内蒙古气象》 1990年第5期38-39,共2页
关键词 大棚 黄瓜 早期定植试验 气修条件 覆盖地膜 覆天膜
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疑难故障回音壁
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《汽车与驾驶维修》 2005年第1期40-40,46,共2页
上次小王遇到了一辆美规奥迪C5A62.8轿车尾气超标的故障,这辆车的故障症状是发动机尾气排放超标,冷车怠速时尾气味道很大,发动机怠速运转正常,中速时加速无力。小王连接诊断仪查出了故障码,故障码的含义是发动机怠速时混合气修正... 上次小王遇到了一辆美规奥迪C5A62.8轿车尾气超标的故障,这辆车的故障症状是发动机尾气排放超标,冷车怠速时尾气味道很大,发动机怠速运转正常,中速时加速无力。小王连接诊断仪查出了故障码,故障码的含义是发动机怠速时混合气修正超出下极限40%:中等负荷时混合气修正超出上极限30%。小王清洗了喷油器、节气门体及进气道,但故障现象没有丝毫好转:后来小王又更换了空气流量计、氧传感器及节气门体,故障也没有排除。小王渴望得到大家的帮助。 展开更多
关键词 发动机怠速 门体 故障码 加速无力 流量计 轿车 诊断仪 排放 气修 超标
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Application of the Analogue-Based Correction of Errors Method in ENSO Prediction 被引量:9
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作者 REN Hong-Li LIU Ying +2 位作者 JIN Fei-Fei YAN Yu-Ping LIU Xiang-Wen 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第2期157-161,共5页
In this study, a method of analogue-based correction of errors(ACE) was introduced to improve El Ni?o-Southern Oscillation(ENSO) prediction produced by climate models. The ACE method is based on the hypothesis that th... In this study, a method of analogue-based correction of errors(ACE) was introduced to improve El Ni?o-Southern Oscillation(ENSO) prediction produced by climate models. The ACE method is based on the hypothesis that the flow-dependent model prediction errors are to some degree similar under analogous historical climate states, and so the historical errors can be used to effectively reduce such flow-dependent errors. With this method, the unknown errors in current ENSO predictions can be empirically estimated by using the known prediction errors which are diagnosed by the same model based on historical analogue states. The authors first propose the basic idea for applying the ACE method to ENSO prediction and then establish an analogue-dynamical ENSO prediction system based on an operational climate prediction model. The authors present some experimental results which clearly show the possibility of correcting the flow-dependent errors in ENSO prediction, and thus the potential of applying the ACE method to operational ENSO prediction based on climate models. 展开更多
关键词 ENSO climatic prediction error correction
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Investigation of the active components and mechanism of Sanao Decoction in treating chronic cough by network pharmacology and molecular docking 被引量:2
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作者 SHENG Mengke LIU Xing +4 位作者 LIAO Yuyao LI Zhixun LYU Lijing YANG Jiaqi SHI Xinyuan 《Digital Chinese Medicine》 2021年第3期191-201,共11页
Objective To investigate the active components and mechanism of Sanao Decoction(三拗汤,SAD)in treating chronic cough based on network pharmacology and molecular docking.Methods Active components and their targets were... Objective To investigate the active components and mechanism of Sanao Decoction(三拗汤,SAD)in treating chronic cough based on network pharmacology and molecular docking.Methods Active components and their targets were obtained from the Traditional Chinese Medicine Systems and Pharmacology Database and Analysis Platform(TCMSP),Bioinformatics Analysis Tool for Molecular mech ANism of Traditional Chinese Medicine(BATMAN-TCM)database,and the literature.The component-target regulatory network and protein-protein interaction(PPI)network were constructed by Cytoscape 3.7.2,and a bioinformatics analysis was performed to identify the significant pathways and their relevant targets.Molecular docking of the core active components and relevant targets was performed.Results A total of 98 active components of SAD and the corresponding 113 drug targets were identified.The component-target regulatory network and PPI network were successfully established.Results of the bioinformatics analysis indicated that 2281 Gene Ontology(GO)terms were enriched in chronic cough,including 2062 terms were in biological processes,77 in cellular components,and 142 in molecular functions,and top 20 significant pathways in Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis.Molecular docking study demonstrated that quercetin,luteolin,kaempferol,and naringenin were in good agreement with the corresponding targets.Conclusion The active compounds of SAD,such as quercetin,luteolin,kaempferol,and naringenin,may act on AKT1,MAPK1,RELA,EGFR,and Bcl-2 and regulate the PI3 K-Akt signaling pathway,AGE-RAGE signaling pathway,and fluid shear stress and atherosclerosis pathway to exert the effects of anti-inflammatory,anti-airway remodeling,anti-oxidant stress effects,and repair airway damage,thus treating chronic cough. 展开更多
关键词 Sanao Decoction(三拗汤 SAD) Chronic cough Network pharmacology Molecular docking Anti-airway remodeling Anti-oxidant stress Repair airway damage
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ANALYSIS AND SIMULATION OF CONTROL MIXER CONCEPT FOR A CONTROL RECONFIGURABLE AIRCRAFT
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作者 李清 郭锁凤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期180-184,共5页
In today's aircraft,the hardware redundancy is driven by the critical surfaces resulting in single point-failures.Reconfiguration technology remoVes the single surface criticality by employing control surfaces wit... In today's aircraft,the hardware redundancy is driven by the critical surfaces resulting in single point-failures.Reconfiguration technology remoVes the single surface criticality by employing control surfaces with aerodynamic redundancy.This paper studies a control reconfiguration scheme based on Control Mixer Concept.A technique for the design of a control mixer for an aircraft with damaged surfaces/actuators using the pseudo-inverse is developed and applied.This paper discusses its applications and limitations based on linear analysis and computer simulation. 展开更多
关键词 flight control systems inverse matrices failuretolerant systems self-repairing systems control mixer aerodynamic redundancy
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Some Insights in Novel Risk Modeling of Liquefied Natural Gas Carrier Maintenance Operations 被引量:1
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作者 T. C. Nwaoha Andrew John 《Journal of Marine Science and Application》 CSCD 2016年第2期144-156,共13页
This study discusses the analysis of various modeling approaches such as genetic algorithms, fuzzy logic and evidential reasoning, and maintenance techniques applicable to the liquefied natural gas (LNG) carrier ope... This study discusses the analysis of various modeling approaches such as genetic algorithms, fuzzy logic and evidential reasoning, and maintenance techniques applicable to the liquefied natural gas (LNG) carrier operations in the maritime environment. The usefulness of these algorithms in the LNG carrier industry in the areas of risk assessment and maintenance modeling as a standalone or hybrid algorithm are identified. This is evidenced with illustrative case studies. 展开更多
关键词 safety risk modeling maintenance LNG carrier fuzzylogic genetic algorithm evidential reasoning
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Analyzing the influences of two types of El Nino on Tropical Cyclone Genesis with a modified genesis potential index
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作者 王法明 杨宇星 杨磊 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第2期452-465,共14页
To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones (TC) is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning ... To understand the impacts of large-scale circulation during the evolution of E1 Nifio cycle on tropical cyclones (TC) is important and useful for TC forecast. Based on best-track data from the Joint Typhoon Warning Center and reanalysis data from National Centers for Environmental Prediction for the period 1975- 2014, we investigated the influences of two types of E1 Nifio, the eastern Pacific E1 Nifio (EP-E1 Nifio) and central Pacific E1 Nifio (CP-E1 Nifio), on global TC genesis. We also examined how various environmental factors contribute to these influences using a modified genesis potential index (MGPI). The composites reproduced for two types of E1 Nifio, from their developing to decaying phases, were able to qualitatively replicate observed cyclogenesis in several basins except for the Arabian Sea. Certain factors of MGPI with more influence than others in various regions are identified. Over the western North Pacific, five variables were all important in the two E1Nifio types during developing summer (July-August-September) and fall (October- November-December), and decaying spring (April-May-June) and summer. In the eastern Pacific, vertical shear and relative vorticity are the crucial factors for the two types of El Nifio during developing and decaying summers. In the Atlantic, vertical shear, potential intensity and relative humidity are important for the opposite variation of EP- and CP-EI Nifios during decaying summers. In the Southern Hemisphere, the five variables have varying contributions to TC genesis variation during peak season (January-February-March) for the two types of E1 Nifio. In the Bay of Bengal, relative vorticity, humidity and omega may be responsible for clearly reduced TC genesis during developing fall for the two types and slightly suppressed TC cyclogenesis during EP-E1 Nifio decaying spring. In the Arabian Sea, the EP-E1 Nifio generates a slightly positive anomaly of TC genesis during developing falls and decaying springs, but the MGPI failed to capture this variation. 展开更多
关键词 two types of E1 Nifio tropical cyclone (TC) modified genesis potential index
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