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Quasi-40-Day Oscillation and Its Teleconnection Struc-ture together with the Possible Dependence on Conversion of Barotropic Unstable Energy of Temporal Mean Flow

Xu Jianjun,

大气科学进展 , 1993,
Abstract: A study is made of the distribution of the diagnostic quantity vector E and the teleconnection structure of 30-50 (quasi-40) day oscillation, together with the dependence on the conversion of barotropic unstable energy of mean flow in terms of ECWMF daily 500 hPa grid data in winter, indicating that the energy transportation is closely associated with the westerly jet position, with zonal (meridional) propagation in the strong (weak) wind region, that considerable conversion of barotropic energy occurs at the jet exit region where low-frequency oscillation gains energy from the mean flow, leading to maximum kinetic energy for the oscillation observed there, which is marked by evident barotropy in striking contrast to the baroclinicity at low latitudes and that the teleconnection core is related to the center of action in the atmosphere and bound up with the pattern of the west wind.
Internal Dynamics of the Generation of Atmospheric Teleconnection Patterns
Li Zhijin,Ji Liren,
Li Zhijin
,Ji Liren

大气科学进展 , 1996,
Abstract: A preferred growing perturbation concept has been introduced into the dynamical study on the generation of atmospheric teleconnection patterns. It is shown that all the important teleconnection patterns observed in the real atmosphere may be established through internal barotropic dynamical processes
Teleconnection Pattern between the Arctic Ice Area and the 500 hPa Geopotential Height Field during the Northern Hemispheric Summer
夏季北极海冰激发的500hPa遥相关型

Fang Zhifang,Tan Youbang,Sui Xuehai,
方之芳
,谭友邦,隋学海

大气科学 , 1991,
Abstract: In this paper, the correlation field between the Arctic ice area and 500 hPa geopotential height field, the one-point correlation maps at 500 hPa, and the 1000-500 hPa thickness difference chart between the strongest arctic ice year and the weakest year for July and August (etc.)are analyzed.According to the foregoing statistical discussion, it may be noted: the arctic ice cold source in summer can be forcing the teleconnection pattern in the northern hemispheric atmosphere. The teleconnection pattern has two-dimensional Rossby wave train and equivalent barotropic structure.The centers of action in the teleconnection pattern can across the westerly jet and into the subtropics, but they only exist in the westerly belt.The teleconnectin pattern effects the atmospheric circulation and weather showing the polar ice being excessive, the polar low pressure being stengthened, the Canada ridge and the Northern American trough being strengthened too, and vice versa.
遥爪型端双氯基聚1,2-丁二烯的合成  [PDF]
李天虎?,金关泰?
推进技术 , 1986,
Abstract: 本文主要叙述以萘锂为引发剂,抽余油为溶剂,丁二烯为单体,三聚氯氰(cnci)3为终止剂,合成遥爪型端双氯基聚1,2-丁二烯的研究;与此同时,还探讨了(cnci)3作为偶联剂的实验结果.此外,对合成的高聚物分子结构,采用紫外、红外、元素分析及gpc等进行了详细的论证工作.
速度型虚拟夹具辅助空间遥操作技术研究  [PDF]
丁炳源,黄攀峰,刘正雄,常海涛
航空学报 , 2013, DOI: 10.7527/S1000-6893.2013.0240
Abstract: 天地间通讯存在大时延是影响空间遥操作性能的主要问题。传统虚拟夹具应用于空间遥操作中,已获得一定的操作性能提升,但不具备动态的预测能力,对于克服时延带来的操作错觉等能力的提升有很大限制。本文提出一种速度型虚拟夹具作用于操作末端,利用操作末端的速度信息,实时改变虚拟夹具的形状,对操作末端在3s时延后的运动进行动态预测。利用方向包围盒(OBB)方法进行图形碰撞检测,能在3s内检测到即将到来的碰撞,按照一定规则产生相应的阻力反馈给操作者,以克服时延引起的误操作,提高遥操作性能。经过多组目标平台的近距离停靠实验,验证了该方法的有效性。
电液手控器型遥操作机器人力反馈控制策略  [PDF]
倪涛,赵丁选,张红彦
农业机械学报 , 2010, DOI: 10.3969/j.issn.10001298.2010.12.039
Abstract: 针对现有电动力反馈操纵装置存在刚度小、力效果不明显的问题,设计了电液伺服力反馈手控器。该手控器在水平方向上具有X、Y两个旋转自由度,每个自由度采用单独的伺服阀控液压马达驱动,空间运动互不干涉。综合传统的力反射伺服型和并列型双向伺服控制算法的优点,提出力/位置偏差复合型主从双向控制策略。以液压手控器为主手,四自由度工程机器人为从手,进行主从遥操作力反馈双向伺服试验研究。验证了力/位置偏差复合型控制算法能有效提高系统响应的快速性和稳定性。
The lnterannual Teleconnection Between the Southern Oscillation and the Northward Extent of High Summer monsoon rain belts in the eastern China
南方涛动与我国东部盛夏季风雨北进程度的年际遥联

Xu Qun,Shi Danping,
徐群
,施丹平

大气科学 , 1993,
Abstract: High positive correlation existed between the Southern Oscillation of June of the previous year and the rainfall in the central eastern China in high summer during recent 34 years. Through statistical calculation and analysis, it was found that this teleconnection is formed under a series of composite air-sea interactions in 15 months starting from the SOI of June of the previous year resulting in the modulated northward extension of next high summer monsoon rain belts in East China.
遥操作机器人执行末端的力反射型变增益力反馈算法  [PDF]
侯敬巍,赵丁选,尚涛,唐新星
吉林大学学报(工学版) , 2008,
Abstract: 在以遥操作工程机器人执行末端为从端的力反馈双向伺服系统中,为了使主端受力真实地反映从端执行末端叉手所受的环境力,在力反射型算法的基础上,提出了一种变增益力反馈算法。根据机器人叉手的运动模型建立叉手液压缸位移与驱动力关系的数学模型,以此调节主端的力反馈控制增益。为了验证该算法的优越性,将该算法与常用的力反射型算法进行了比较实验。实验证明,该算法在保证系统稳定性的前提下,精确地反映了机器人叉手在运动中的惯性力和阻尼力所带来的影响,操作者可以更为真实地感知机器人从手所受环境力的变化,有利于系统工作性能的提高。
Difference of the Atmospheric Teleconnection Patterns between Winter and Summer over the Northern Hemisphere and Its Relation with the Air Temperature Fields
北半球大气遥相关型冬夏差异及其与温度场关系的探讨

CHEN Fangli,LI Weibiao,
陈芳丽
,黎伟标

大气科学 , 2009,
Abstract: The different features of the atmospheric teleconnection patterns between winter and summer over the Northern Hemisphere(NH) and their relations with the air temperature fields are studied using the 55 years NCEP/NCAR reanalysis data.It is found that there are obvious differences in the routes of the atmospheric teleconnection between winter and summer over the NH.The teleconnection route in winter exhibits meridional features while the teleconnection route is noticeably zonal in summer.Results also show th...
A Study of the Processes of East Asia - Pacific Teleconnection Pattern Formation and the Relationship to ENSO
东亚-太平洋遥相关型形成过程与ENSO盛期海温关系的研究

ZONG Hai-Feng,ZHANG Qing-Yun,CHEN Lie-Ting,
宗海锋
,张庆云,陈烈庭

大气科学 , 2008,
Abstract: By using NCEP/NCAR reanalysis datasets,extended reconstructed sea surface temperature(ERSST) data and Chinese 730-station ten days mean rainfall for the period of 1961-2000,the relationship between the rainfall of China and circulation during the Meiyu period and pre-winter sea surface temperature(SST) is studied through singular value decomposition(SVD),extended singular value decomposition(ESVD),composition and correlation methods.On this basis,the evolution of ENSO-related SST and circulation anomalies over East Asia and the Pacific and their persistence,particular attention being paid to the formation of the East Asia-Pacific(EAP) teleconnection pattern related to the Meiyu rainfall in the Yangtze River valley,is investigated.The results show that the appearance of EAP teleconnection pattern in the Meiyu period is closely linked to the remote ENSO forcing.The formation of the EAP teleconnection pattern linked to ENSO in the mature Phase consists of three key processes:(1) The formation and persistence of anomalous anticyclone in the western North Pacific: The anticyclone persists from the mature El Nio winter to the ensuing summer,leading to the western North Pacific subtropical high strengthening and southward shifting;(2) the decay of the East Asia trough: The weak East Asia trough causes the path of cold air activity more northward and eastward and the SST cooling in Oyashio and warming in Kuroshio;(3) the continuous development of the PNA(Pacific-North American) teleconnection pattern: The blocking high over the region of Alaska extends westward,making the geopotential height increase over the Arctic Ocean.The above processes of the East Asia trough and PNA teleconnection pattern will play important roles in the establishment of the blocking high over the Sea of Okhotsk in early summer through local air-sea interaction and adjustment of atmosphere circulation. Furthermore,the analysis shows that the persistence of the anomalous circulation and SST patterns is much longer in ENSO years after the mature phase than non-ENSO years.There is strong coupled relation between the circulation and SST in ENSO years.The ENSO-related circulation anomaly could lead to the Pacific SST anomaly which in turn could result in a bigger stability of anomalous circulation pattern.So it has obvious delayed effect on East Asia monsoon and China's weather and climate process in early summer after El Nio mature phase.
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