GPT3模型估计对流层产品精度检验与分析     

杨飞  郭际明  李弈韬  唐伟  郭伟 《大地测量与地球动力学》2021,41(11):1123-1126

利用全球范围内224个IGS测站2019年的高精度对流层产品,对GPT3模型估计的天顶对流层延迟和大气水平梯度信息进行精度检验和分析。结果表明,精度在空间和时间分布上存在差异性,天顶对流层延迟、南北和东西方向大气水平梯度的平均偏差和均方根误差分别为0.12 mm/37.2 mm、-0.05 mm/0.49 mm、0.08 mm/0.57 mm。  相似文献   

Improvements in WRF simulation skills of southeastern United States summer rainfall: physical parameterization and horizontal resolution   总被引：2，自引：0，他引：2  

Laifang Li  Wenhong Li  Jiming Jin 《Climate Dynamics》2014,43(7-8):2077-2091

Realistic regional climate simulations are important in understanding the mechanisms of summer rainfall in the southeastern United States (SE US) and in making seasonal predictions. In this study, skills of SE US summer rainfall simulation at a 15-km resolution are evaluated using the weather research and forecasting (WRF) model driven by climate forecast system reanalysis data. Influences of parameterization schemes and model resolution on the rainfall are investigated. It is shown that the WRF simulations for SE US summer rainfall are most sensitive to cumulus schemes, moderately sensitive to planetary boundary layer schemes, and less sensitive to microphysics schemes. Among five WRF cumulus schemes analyzed in this study, the Zhang–McFarlane scheme outperforms the other four. Further analysis suggests that the superior performance of the Zhang–McFarlane scheme is attributable primarily to its capability of representing rainfall-triggering processes over the SE US, especially the positive relationship between convective available potential energy and rainfall. In addition, simulated rainfall using the Zhang–McFarlane scheme at the 15-km resolution is compared with that at a 3-km convection-permitting resolution without cumulus scheme to test whether the increased horizontal resolution can further improve the SE US rainfall simulation. Results indicate that the simulations at the 3-km resolution do not show obvious advantages over those at the 15-km resolution with the Zhang–McFarlane scheme. In conclusion, our study suggests that in order to obtain a satisfactory simulation of SE US summer rainfall, choosing a cumulus scheme that can realistically represent the convective rainfall triggering mechanism may be more effective than solely increasing model resolution.  相似文献   

大兴安岭林区地闪放电特征的观测与分析   总被引：4，自引：2，他引：2  

王东方  宣越健  刘继明 《大气科学》2011,35(1):147-156

利用2009年夏季在大兴安岭林区开展的雷暴及闪电的多站GPS同步观测资料,详细分析了该地区的地闪放电特征.通过对464次地闪资料的分析,发现具有单次回击的地闪所占的比例高达69,且正地闪比例较高,达到了22%.对连续电流的统计表明,约有27%的地闪伴随有连续电流过程且长连续电流过程主要出现在具有单次回击的负地闪中,其平...  相似文献   

"嫦娥"工程与月球测绘学   总被引：3，自引：0，他引：3  

孔祥元  张松林  魏二虎  黄劲松  郭际明 《大地测量与地球动力学》2004,24(1):117-120

介绍了我国月球探测计划“嫦娥”工程的发展概况，提出了月球测绘学的概念及基本任务，总结了当今世界上月球测绘的主要成果，指明了我国发展月球测绘工程总体方略和具体措施。  相似文献   

支持向量机辅助下的智能手机行人运动模式识别     

郭际明  王威  张帅 《测绘通报》2018,(2):1-5

利用智能手机的内置多集成传感器作为数据采集工具,结合支持向量机（SVM）进行行人运动模式识别是智能识别领域中一个重要方法。本文针对行人静止、行走、上/下楼梯、上/下厢梯、上/下扶梯这几种常见的室内运动模式,选取有效特征,利用线性核函数SVM建立分类模型对测试数据进行了识别。试验结果表明：从所采集的行人运动模式的数据中提取13个特征,可在3 s的数据滑动窗口0.5 s数据采样间隔下,得到96.4%的识别正确率。  相似文献   

城市地质学理论研究     

郑桂森  卫万顺  刘宗明  王继明  于春林  徐吉祥  李小龙 《城市地质》2018,(2):1-12

本文在系统研究国内外城市地质学理论研究与工作实践基础上,系统分析并拓展了城市地质学的内涵与外延;根据城市可持续发展的需求,提出了保证城市不同发展阶段地质安全是城市地质学理论研究的根本任务和永恒主题;明确提出了城市地质学研究的三个科学问题,即城市选址安全底限问题、城市发展规模上限问题、城市发展可持续性问题;由此构建了区域地质条件适宜性评价、地质资源环境承载力评价、城市地质作用研究,三方面的城市地质学理论体系。  相似文献   

东天山博格达造山带东段七角井组枕状玄武岩地球化学特征及构造背景探讨   总被引：1，自引：0，他引：1  

孙吉明  白建科  朱小辉  牛峥  马中平 《地质学报》2018,92(3):520-530

东天山博格达东段下涝坝南部地区七角井组枕状玄武岩地球化学特征表明,玄武岩属于亚碱性拉斑玄武岩系列,具有轻稀土轻微富集的特征((La/Yb)N介于1.89~2.21之间)及弱的Eu负异常(δEu=0.89~0.96),并且显示出岛弧火山岩的Nb-Ta-Ti负异常特征。微量元素中除活动性较强的元素(Cs、Rb、Ba)其余元素均为N-MORB的1~2倍,接近下地壳的含量。(La/Nb)N介于1.82~2.62之间,远远大于1,暗示了该地区的火山岩在上升过程中可能遭受了地壳的混染。Zr含量大于142×10~(-6)、Zr/Y值大于4,也显示了板内玄武岩的特征。在多种环境判别图解中均落入大洋岛弧边缘,靠近IAT和MORB或板内构造环境区域内,显示了同时具有IAT和MORB的特征,结合研究区内的早石炭世地层的沉积构造环境,笔者认为博格达东段下涝坝南部地区在早石炭世期间处于一种伸展(弧后拉张)的构造环境。  相似文献   

地表浅部地震勘探方法在城市隐伏活动断裂调查中的应用     

徐吉祥  张晓亮  李潇  王继明  薛爱民  舒律 《城市地质》2022,17(1):79-84

混合源面波与三分量频率谐振勘探方法是近年来兴起的一套新型城市地球物理探测技术.以黄庄-高丽营断裂为例,采用主动源多道瞬态面波、混合源多道瞬态面波勘探和三分量地震频率谐振勘探方法进行实验研究.研究结果表明,主动源面波勘探可清晰展示地表以下15 m的地质构造;混合源多道瞬态面波,综合主动源信号和被动源(噪声)优势,增加其探...  相似文献   

Applications of graph theory to gross error detection for GPS geodetic control networks     

Samwel Katambi  Guo Jiming  Kong Xiangyuan 《地球空间信息科学学报》2013,16(4):26-31

This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three components. In this algorithm the gross error detection is undertaken through loops of different spanning trees using the “Loop Law” in which the individual components ΔX, ΔY and ΔZ sum up to zero. If the sum of the respective vector components ΩX, ΩY and ΩZ in a loop is not zero and if the error is beyond the tolerable limit (ε>ω), it indicates the existence of gross errors in one of the baselines in the loop and therefore the baseline must be removed or re-observed. After successful screening of errors by graph theory, network adjustment can be carried out. In this paper, the GPS data from the control network established as refence system for the HP Dam at Baishan county in Liaoning province is presented to illustrate the algorithm.  相似文献   

Investigation of ionosphere TEC distribution in China region by GIM model     

Guo Jiming  Lin Hui 《地球空间信息科学学报》2013,16(3):197-200

In this paper, the TEC in China region is calculated by final GIM model and plotted as contour maps, the TEC value calculated from dual frequency GPS measurements (carrier-phase and pseudorange) is used as the reference truth and the TEC values from GIM models are then compared with the reference truth, and the accuracy and performance of GIM model in China region are analyzed and concluded.  相似文献