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Identification and Interpretation of Earth’s Atmosphere Dynamics’ and Thermodynamics’ Similarities between Rogue Waves and Oceans’ Surface Geostrophic Wind
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作者 César Mbane Biouele 《Open Journal of Marine Science》 2016年第2期238-246,共9页
In their daily practices, meteorologists make extensive use of the geostrophic wind properties to explain many weather phenomena such as the meaning and direction of the horizontal winds that take place around the low... In their daily practices, meteorologists make extensive use of the geostrophic wind properties to explain many weather phenomena such as the meaning and direction of the horizontal winds that take place around the low atmospheric pressures. The biggest challenge that faces the public who is interested in information disseminated by meteorologists is to know exactly what means the geostrophic wind. Besides the literal definitions scattered in very little scientific work, there is unfortunately no book which gives importance to the algebraic definition of the geostrophic wind. Our work shows that to better understand the behavior of natural phenomena, it is essential to combine the theories with based observations. Obviously, observations cannot be relevant without a theory that guides the observers. Conversely, no theory can be validated without experimental verification. Synoptic observations show that in the “free atmosphere!” the wind vectors are very nearly parallel to isobars, and the flow is perpendicular to the horizontal pressure gradient force, at least at any given instant. This kind of information recommends great caution when making geostrophic approximations. Our work also shows that for tornadoes, there is no need to move away from the surface of the oceans to observe the geostrophic balance. Undoubtedly, identification and interpretation of earth’s atmosphere dynamics’ and thermodynamics’ similarities between rogue waves and oceans’ surface geostrophic wind will be an easy exercise to researchers who will give importance to result provided by this paper. 展开更多
关键词 earth’s Atmosphere dynamics and Thermodynamics similarities Rogue Waves Ocean’s surface Geostrophic Wind
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The principal moments of inertia calculated with the hydrostatic equilibrium figure of the Earth
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作者 Chengjun Liu Chengli Huang Mian Zhang 《Geodesy and Geodynamics》 2017年第3期201-205,共5页
As an indication of the Earth's mass distribution, the principal moments of inertia (PMOI, i.e., A, B, C) of the Earth are the basic parameters in studies of the global dynamics of the earth, like earth nutation, a... As an indication of the Earth's mass distribution, the principal moments of inertia (PMOI, i.e., A, B, C) of the Earth are the basic parameters in studies of the global dynamics of the earth, like earth nutation, and the geophysics. From the aspect of observation, the PMOI can be calculated from the spherical coefficients of observed gravity field. In this paper, the PMOI are calculated directly according to its definition with the figures of the Earth's interior derived by a generalized theory of the hydrostatic equilibrium figure of the Earth. We obtain that the angle between the principal axis of the maximum moment of PMOI and the rotational axis is 0.184~, which means that the other two principal axes are very closely in the equatorial plane. Meanwhile, B-A is 1.60 x 10-5 MR2, and the global dynamical flattening (H) is calculated to be 3.29587 ~ 10-3, which is 0.67% different from the latest observation derived value Hobs(3.273795 × 10 ^-3) (Petit and Luzum, 2010), and this is a significant improvement from the 1.1% difference between the value of H derived from traditional theories of the figure of the Earth and the value of Hobs. It shows that we can calculate the PMOI and H with an appropriate accuracy by a gener- alized theory of the hydrostatic equilibrium figure of the Earth. 展开更多
关键词 Principal moments of inertia (PMOI) Hydrostatic equilibrium figure The earths dynamical flattening
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The Possibilities of Using the Minimax Method to Diagnose the State of the Atmosphere
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作者 Elena S.Andreeva 《Journal of Atmospheric Science Research》 2023年第2期42-49,共8页
The article is devoted to the discussion of the possibilities of approbation of one of the probabilistic methods of verification of evaluation works-the minimax method or the method of establishing the minimum risk of... The article is devoted to the discussion of the possibilities of approbation of one of the probabilistic methods of verification of evaluation works-the minimax method or the method of establishing the minimum risk of making erroneous diagnoses of the instability of the planetary boundary layer of air.Within the framework of this study,the task of probabilistic forecasting of diagnostic parameters and their combinations,leading in their totality to the formation of an unstable state of the planetary boundary layer of the atmosphere,was carried out.It is this state that,as shown by previous studies,a priori contribution to the development of a number of weather phenomena dangerous for society(squalls,hail,heavy rains,etc.).The results of applying the minimax method made it possible to identify a number of parameters,such as the intensity of circulation,the activity of the Earth’s magnetosphere,and the components of the geostrophic wind velocity,the combination of which led to the development of instability.In the future,it is possible to further expand the number of diagnosed parameters to identify more sensitive elements.In this sense,the minimax method,the usefulness of which is shown in this study,can be considered as one of the preparatory steps for the subsequent more detailed method for forecasting individual hazardous weather phenomena. 展开更多
关键词 Minimax method Dangerous weather phenomena Atmospheric instability Boundary layer of the atmosphere Intensity of atmospheric circulation earth’s magnetosphere Geostrophic wind
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Modeling Daily Average Temperatures in a Coastal Site of Central Africa: An Analysis of Seasonal Divisions
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作者 Jean-Pierre Bell Esther C. Modi-Mbog +1 位作者 Nicodeme Djiedeu Laurent Nana 《Atmospheric and Climate Sciences》 2023年第3期341-352,共12页
The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This pap... The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This paper implements a simple analytical approach in order to generate daily average temperatures which implicitly accounts for surface heating and drivers through a comprehensive representation of station-based temperature records on a universal standard calendar propagated by the earth’s dynamics features. The modeled and observed pattern of daily temperatures exhibits a close agreement with the level of strength agreement exceeding 0.56. The extreme high and low values of the observed temperature patterns are equally well captured although model underestimates the probability of temperatures around the two modal peaks (~25.6℃ and 27.5℃). Additionally, a theoretical thermal-based division led to the identification of six seasons, including two hot and cold periods along with two pairs of mixed hot-cold. The theoretical division proposed here appears to be a good approximation for the understanding of rainfall seasonality in this area. 展开更多
关键词 Daily Temperature Estimates earth’s dynamics seasonal Divisions
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从31届地质大会看火成岩石学的研究动向 被引量:15
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作者 廖忠礼 莫宣学 +3 位作者 喻学惠 赵志丹 苏尚国 董国臣 《岩石矿物学杂志》 CAS CSCD 北大核心 2001年第3期360-366,共7页
主要根据第 31届国际地质大会上关于花岗质岩浆作用与成矿 ,花岗岩系统及元古宙岩石圈过程 ,玄武岩 ,碱性侵入体的成因与侵位 ,碳酸岩、金伯利岩、钾镁煌斑岩及相关岩石 ,造山带酸性与中性火山岩 ,火山作用等方面的发言、论文及摘要 ,... 主要根据第 31届国际地质大会上关于花岗质岩浆作用与成矿 ,花岗岩系统及元古宙岩石圈过程 ,玄武岩 ,碱性侵入体的成因与侵位 ,碳酸岩、金伯利岩、钾镁煌斑岩及相关岩石 ,造山带酸性与中性火山岩 ,火山作用等方面的发言、论文及摘要 ,结合其它资料 ,对近些年来国际、国内火成岩石学领域的新进展和研究动向进行讨论。认为从 2 0世纪末到 2 1世纪初 ,在地球动力学和全球变化的总框架下 ,在人类对资源、环境、减灾重大需求的推动下 ,火成岩石学在地球物质科学、岩石探针、大火成岩省事件与超级地幔柱、地幔动力学。 展开更多
关键词 火成岩石学 地球物质科学 花岗质岩浆作用 玄武岩 碱性岩 岩石探针 大火成岩省事件 超级地幔柱 地幔动力学
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地球深内部探测及动力学研究 被引量:2
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作者 傅容珊 黄建华 杨亭 《大地测量与地球动力学》 CSCD 北大核心 2012年第3期139-151,159,共14页
近20年来人类对于地球深内部的探测和认识已经上升到一个新的层次,滋生出许多新的研究热点。一系列最新发现集中于地球深内部研究领域。简述了这一领域研究的成果,探讨其未来发展和研究的方向。
关键词 地球深内部 板块构造 地幔动力学 地震层析成像 地球动力学
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Surveys on magnetospheric plasmas based on the Double Star Project (DSP) exploration 被引量:5
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作者 C. P. ESCOUBET C. M. CARR +4 位作者 H. RME A. FAZAKERLEY H. LAAKSO I. DANDOURAS M. DUNLOP 《Science China(Technological Sciences)》 SCIE EI CAS 2008年第10期1639-1647,共9页
The equatorial and polar satellites of the Double Star Project (DSP) were launched successfully on December 29, 2003 and July 25, 2004, respectively, and both of them are operating smoothly. The DSP provides a good op... The equatorial and polar satellites of the Double Star Project (DSP) were launched successfully on December 29, 2003 and July 25, 2004, respectively, and both of them are operating smoothly. The DSP provides a good opportunity for investigat-ing the structure of the magnetosphere. Based on the DSP data collected during 2004, we have surveyed the distribution of the magnetic fields and plasmas in the magnetosphere. It is found that: (1) Near the Earth’s equatorial plane within geo-centric distances of less than 7 RE, the Earth’s magnetic field is dipolar. In the vi-cinity of the magnetopause, the magnetic field is enhanced by a factor of about 1.5, and on the nightside, the magnetic field can vary significantly from the Earth’s di-pole field, likely caused by the presence of the near-Earth tail current sheet. (2) In the day-side magnetosheath, the electron and ion densities are usually both in the range of 10―30 cm?3; the ion and electron temperatures are usually about 200 and 50 eV, respectively. The flow pattern is usually smooth, with a low velocity in the subsolar region and with significantly higher velocities in the dawn and dusk flanks. (3) In the region between the magnetopause and plasmasphere the density is low, approximately 0.5―5 cm?3, and the temperature is high, about 1―10 keV for ions and 0.1―5 keV for electrons. The ion temperature has an apparent anisotropy, with the ratio of the perpendicular and parallel temperatures being about 1.0―1.3 for the night- and dusk-side magnetosphere and about 1.3―2.0 for the day- and dawn-side magnetosphere. There is an evident sunward convection of about 50 km/s in the magnetosphere. On the dawn side, the flow becomes somewhat turbulent, and in the vicinity of the night-noon meridian plane, the convection is rather slow. (4) The high-energy electrons with energies higher than 2 MeV are mainly located in the regions with 3 < L < 4.5; the size of the high-energy electrons area varies with time, it may expand and shrink occasionally according to different solar wind conditions and magnetic activities. 展开更多
关键词 earth’s magnetosphere sPACE EXPLORATION GEOMAGNETIC field sPACE PLAsMAs
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Calculation of the extreme ultraviolet radiation of the earth's plasmasphere 被引量:4
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作者 FOK Mei-Ching 《Science China(Technological Sciences)》 SCIE EI CAS 2010年第1期200-205,共6页
The dynamic global core plasma model(DGCPM) is used in this paper to calculate the He+ density distribution of the Earth's plasmasphere and to investigate the configurations and 30.4 nm radiation properties of the... The dynamic global core plasma model(DGCPM) is used in this paper to calculate the He+ density distribution of the Earth's plasmasphere and to investigate the configurations and 30.4 nm radiation properties of the plasmasphere.Validation comparisons between the simulation results and IMAGE mission observations show:That the equatorial structure of the plasmapause is mainly located near 5.5 RE and the typical scale of plasmasphere shrinking or expansion within 10 min is approximately 0.1 RE;that the plasmaspheric shoulders are formed and rotate noon-ward from the dawn sector under the conditions of strong southward turning of the interplanetary magnetic field(IMF);that the plasmaspheric plumes will rotate dawn-ward from the night sector and become narrow for the southward turning of the IMF.The simulated images from the lunar orbit show that the plasmasphere locating within the geocentric distance of 5.5 RE corresponds to field of view(FOV) of 10.7°×10.7° for the moon-based EUV imager,and that the 30.4 nm radiation intensity of the plasmasphere is 0.1-11.4 R.The plasmaspheric shoulders and plumes locating toward the moon-side are for the first time simulated with typical scale level of 0.1 RE from the side view of the moon.These simulated results provide an important theoretical basis for the lunar-based EUV camera design. 展开更多
关键词 earth’s PLAsMAsPHERE dynamic global CORE plasma model EXTREME ULTRAVIOLET radiation lunar-based imaging
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基于辛-谱元方法的地球自由振荡保弥散衰减数值模拟
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作者 李冰非 李小凡 +1 位作者 李峰 龚飞 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2021年第11期4022-4030,共9页
对大地震激发的全球自由振荡的研究是探查地球内部结构的重要研究方向之一.以地球自由振荡数值模拟高精度、长时程、全球模拟的需求为导向,本文提出了一种适用于地球自由振荡高精度模拟的辛格式-谱元保弥散数值模拟方法.真实地球介质中... 对大地震激发的全球自由振荡的研究是探查地球内部结构的重要研究方向之一.以地球自由振荡数值模拟高精度、长时程、全球模拟的需求为导向,本文提出了一种适用于地球自由振荡高精度模拟的辛格式-谱元保弥散数值模拟方法.真实地球介质中弹性波能量的衰减成因复杂,对于甚低频情形,地球自由振荡的弥散衰减不容忽视.本文将保结构数值方法拓展至非保守动力学系统,发展了适用于弥散-黏弹阻尼介质弹性波方程的保弥散低阶辛格式数值模拟方法,将其应用于全球尺度地球自由振荡衰减效应数值模拟.数值模拟结果表明等效弥散衰减为地球深部(地核)自由振荡衰减的重要成分,并得出地球外核的等效弥散衰减系数.本文提出的方法为通过自由振荡研究探索地核非均匀性提供了一条的新途径. 展开更多
关键词 地球自由振荡 地球内部结构 保结构数值模拟方法 非保守动力学系统 弥散衰减
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动态地球磁层的时空剖分编码
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作者 王慈枫 胡晓彦 +2 位作者 邹自明 李云龙 白曦 《空间科学学报》 CAS CSCD 北大核心 2022年第5期891-900,共10页
动态地球磁层时空剖分模型借鉴了广泛应用于地学大数据的地球格网模型思想,实现了面向地球磁层的动态、非规则化物理空间的多层级剖分,且剖分格网形变稳定,可以实现一定范围内地球磁层时空特性的形式化。在此基础上,对剖分得到的时空格... 动态地球磁层时空剖分模型借鉴了广泛应用于地学大数据的地球格网模型思想,实现了面向地球磁层的动态、非规则化物理空间的多层级剖分,且剖分格网形变稳定,可以实现一定范围内地球磁层时空特性的形式化。在此基础上,对剖分得到的时空格网进行编码表达,以便于计算机存储和处理,这是构建地球磁层大规模观测数据统一管理基础时空框架的另一个关键问题。由于地球磁层特殊的时空特性,经典、单一思路的地学编码方案较难完整地反映格网间的时空关系,因此难以支持格网间的基础时空关系计算。本文融合了整数坐标编码与Morton曲线编码的基本思路,实现了对漂移壳剖分格网的高效编码方案设计,完成了动态地球磁层的时空框架构建,从而为地磁数据的高效组织和处理奠定了基础。实验证明,本文提出的编码方案编码效率较高,且可以支持高效的相邻关系计算,为动态地球磁层多源、多层级、异构的大规模观测数据的组织与计算提供了一种解决方案。 展开更多
关键词 动态地球磁层 漂移壳 动态时空剖分 时空编码方案
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A storm-time ring current model(STRIM)
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作者 YU YiQun MA LongXing +4 位作者 WEI ZiMing AN DePeng WU HaiJun LU Hao Yu CAO JinBin 《Science China(Technological Sciences)》 CSCD 2024年第12期3890-3908,共19页
The ring current,one of the most important current systems around the Earth,intensifies during geomagnetic storms and is believed to be the main reason for large-scale magnetic field perturbations in the geospace envi... The ring current,one of the most important current systems around the Earth,intensifies during geomagnetic storms and is believed to be the main reason for large-scale magnetic field perturbations in the geospace environment.Understanding how the ring current builds up and evolves during geomagnetic storms is of great importance not only for advancing the knowledge of the Sun-Earth system but also for improving the modeling capability of predicting hazardous space weather events.Focusing on the national strategic needs in the space weather prediction,in this study,we establish a ring current model named storm time ring current model(STRIM).The STRIM comprehensively embraces key physical processes in association with ring current dynamics,including plasma source injections from the nightside plasmasheet and transport around the Earth,charge-exchange with neutral hydrogens,Coulomb collisions with thermal plasma,wave-particle interactions,field line curvature scattering,and precipitation loss down to the upper atmosphere.The electric fields needed for particle motion can be optionally taken from empirical models or self-consistently calculated,while the magnetic field configuration is obtained from Tsyganenko 2005 model.Simulation results are verified against the published literature and validated with in-situ satellite or ground-based observations and are found to have the same high-level capability and fidelity as other well-known published models.We also discuss future tasks of fostering the model's performance and potential applications. 展开更多
关键词 kinetic ring current models bounce-averaged Fokker-Planck equation earth inner magnetosphere ring current dynamics magnetic storms
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基于天琴一号观测数据反演地球重力场模型 被引量:3
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作者 周浩 罗志才 +2 位作者 周泽兵 谷德峰 涂良成 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2022年第9期117-125,共9页
天琴一号卫星搭载了静电悬浮加速度计、GNSS接收机和星象仪,可实现地球重力场探测的高低卫星跟踪卫星技术.这里利用自主研制的动力法反演软件,采用天琴一号(TQ-1:Tianqin-1)30 h观测数据反演了截断至15阶次的静态地球重力场模型,计算结... 天琴一号卫星搭载了静电悬浮加速度计、GNSS接收机和星象仪,可实现地球重力场探测的高低卫星跟踪卫星技术.这里利用自主研制的动力法反演软件,采用天琴一号(TQ-1:Tianqin-1)30 h观测数据反演了截断至15阶次的静态地球重力场模型,计算结果表明:TQ-1卫星数据反演的地球重力场模型在15阶次内的信噪比均大于1,说明利用TQ-1数据具备实现15阶次地球重力场的反演能力;通过与包含8 a高低卫星跟踪卫星观测信息的AIUB-CHAMP03S模型对比可知,利用TQ-1卫星数据反演的地球重力场模型位系数误差整体优于10^(-8)量级;通过与包含13 a低低卫星跟踪卫星观测信息的HUST-Grace2016s模型对比可知,利用TQ-1卫星数据反演的地球重力场模型可获取全球格网重力异常和全球格网大地水准面信息,二者空间分布特征较为一致.计算结果为采用我国自主研发的高低卫星跟踪卫星技术获得的首个地球重力场模型,表明我国具备了采用该技术获取地球重力场模型的能力,可为发展我国自主研发的重力卫星提供重要技术参考. 展开更多
关键词 天琴一号 地球重力场 加速度计 动力法 卫星重力
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核素在引力常数减小过程中的放射性衰变 被引量:9
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作者 袁立新 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期252-260,共9页
推动地球板块运动、地震及火山活动的动力机制,地球圈层及岩石结构的形成,以及地球资源和能源等,是当代地球物理急待解决的问题.依据引力常数变化对核素的作用,以及核物理基本原理,建立起了一个核素结构随引力常数变化的动态核力模型,... 推动地球板块运动、地震及火山活动的动力机制,地球圈层及岩石结构的形成,以及地球资源和能源等,是当代地球物理急待解决的问题.依据引力常数变化对核素的作用,以及核物理基本原理,建立起了一个核素结构随引力常数变化的动态核力模型,此核力模型与宇宙天体的演化过程密切相关且同步.此模型对上述多方面存在问题的解决,作了合理的解释.通过引力常数减小而产生的地球结构能释放的论证,求证出核素放射性衰变是地球结构能的释放方式;论证及量化计算了地幔岩石化学结合能是对于地球结构能释放或核衰变能的吸收;证明了引力常数减小对宇宙宏观与原子核微观作用的内在一致性或宏观与微观的统一性;得出了原子核结构的稳定和非稳定性具有相对性的结论. 展开更多
关键词 引力常数减小 动力机制 地球结构能的释放 动态核力模型 核素放射性衰变 宏观与微观的统一
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一种面向动态地球磁层的数据组织模型和高效检索 被引量:2
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作者 王慈枫 邹自明 +2 位作者 胡晓彦 李云龙 白曦 《地球物理学进展》 CSCD 北大核心 2022年第4期1492-1499,共8页
随着探测和考察手段的丰富,地磁观测数据大量增长且呈现出多源、多分辨率、异构等特点.传统的语义组织模型难以支持大规模异构数据的高效存储、处理与关联分析,应建立一种面向动态地球磁层的时空数据组织模型,在提高数据检索效率的基础... 随着探测和考察手段的丰富,地磁观测数据大量增长且呈现出多源、多分辨率、异构等特点.传统的语义组织模型难以支持大规模异构数据的高效存储、处理与关联分析,应建立一种面向动态地球磁层的时空数据组织模型,在提高数据检索效率的基础上兼容多检索模式,以满足数据的高效检索、呈现、分析和过程事件的演化等应用需求.本文基于漂移壳对地球磁层进行多层级时空剖分及编码,实现了地球磁层时空框架的建模;结合多卫星能量粒子探测数据及辐射带粒子通量模型数据,设计了基于该时空框架的数据重组方案,进行了数据一致性验证;基于HBase数据库及HBase协处理器技术构建了重组方案对应的物理存储模型,并设计了查询算法用于对该模型进行实验验证.实验结果表明:本文提出的数据组织模型实现了数据和时空框架之间的有效映射,极大地提高了数据检索效率,并且兼容了语义检索、时空位置检索、时空关系检索等多种模式,为动态地球磁层大规模观测数据组织与高效检索提供了一种新方案. 展开更多
关键词 动态地球磁层 时空框架 HBase存储方案 数据组织模型 数据检索
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