共查询到20条相似文献，搜索用时 500 毫秒
1.
????1999~2009???IGS????????????????(TEC)????????????TEC???????I????dc????????????I????nc?????????仯??????仯????????о????????????????????????????????I????dc???????????????????????????????????????????????????????????????????????????I????dc?????????仯??????????????I????nc????????γ????????а???仯??????????I????dc???????I????nc????????仯????????????仯???仯????????????????85%?????????I????dc????????????????????????I????dc???????I????nc?????????仯?????澭γ??仯???????????????????仯??????????????????????I????dc????????I????nc?????????????P????????????????????????????0.9???????????D????st????K??p??A??p???????????????????????????С??0.4??????????????????????????????????????????TEC????仯????????????á? 相似文献
2.
????GPS??????????BD2????????????????????????λ?????????????????????????????????Helmert????????????????????????α?????????λ??????α????λ????λ????λ????????з??????????????Helmert????????????????GPS/BD2????λ????????????α?????????????21????λ????????11?? 相似文献
3.
μ������ֽ�ؿ�ˮƽ�˶���Ӧ������ 总被引：3，自引：2，他引：1
????2001??2004??GPS?????????о?μ??????????????????????????????????????????????????????????????????1)????????????????????, ?о????????????????????????????????,????μ??????в????????????????????????GPS????????????????2)???е???????-????-????-??????????????????????????,???????????????,????????????-????-????-μ???????С?????????????? 相似文献
4.
���ڸĽ���С�������õĵؿǴ�ֱ�α���� 总被引：1，自引：0，他引：1
??????С?????????????????α??????α???????????α????α?????????????????????????????????????С??????????????????????α????????????????????????????α????α??????????????????С???????÷??????????????????????????????α????е???α??????????????С???????÷??????????α????????????????????????????????????????????????????ú????Э?????????????Ч??????????α????α??????????α?????????????????????????GPS?????????????????÷???????????????????????α????α???????????????Ч???????????? 相似文献
5.
????InSAR????У????SAR???????????????????????????????????μ??????????????--??????κ???????????????????????????????GPS????????ж????????????????????????????????????????????????????????GPS????????????????????????mm??????????InSAR????У??????? 相似文献
6.
???GPS/BDS????λ?й?????????????Helmert??????????????????????????????IGG????????????Helmert?????????????????????????У??????GPS/BDS??????????α????λ????λ????λ??顣?????????????Helmert????????????????????????????????????????????????λ??????????? 相似文献
7.
????EGM2008?????????????????????????CRUST1.0???????-?????????????????????????й????Moho??????????????й????Moho?????????????????о????????? 相似文献
8.
????1951??????????????????1999-2007???GPS???????????????????α???????о???????????????岻????ε????α???????????α?????8.0??????????????????????????????8.0?????????????α?????????????α???????????????????????????????????????骲???????????й????λ?????????????????????????????????????γ???????????????????????????????????? 相似文献
9.
��-�����ٲ���ģʽ�й���߶ȵ��Ż�ѡȡ 总被引：14，自引：5，他引：9
???????????????????????????????120??GRACE???????????????????????1????????????????100 km??????????????10??????????????????????????????GRACE????????????????2????????????????????????????500 km?????????20?????????????????0.221?????Ч??????50???80???100???120?????????9.621????92.857????418.957????1 895.369????3??????????????????????????????????????????JPL??????GRACE?????????120???????500 km????????????????澫???17.316 cm????????450 km??400 km??350 km?????????????????1.566????4.502????10.871????4?? ???????????????????й?????????350 ~ 400 km??????120????????????????? 相似文献
10.
????GPS?????????????????????????????????????????????????????????????????GPS????????????????????Χ????λ??????к??????????????????????????????????????????????????????????????ε?????????????ó????3???????????????????????????η?Χ????????????????λ???仯???????????????????Χ????????????????飬???????????????????С???????????λ????е??????????????????????????ο????????????????????????????????????????ο??嶫????γ????????η?????????????硪??????????????γ????????????????????????ο???????????ο??嶫????????????????й???????????? 相似文献
11.
世界是一个相互关联的网络。物质、信息、能量等的移动或交换嵌入地理空间形成的地理多元流网络,为从地理和网络角度研究全球性问题提供了新的视角。如何构建多主题、时变的地理多元流网络,识别其网络结构、时变规律和关联模式,并为解决全球性的人口移动、航空交通、国际关系、国际贸易等问题提供支持,是迫切需要解决的问题。本文提出了全球尺度地理多元流网络化挖掘及关联分析的研究框架,包括：多源数据收集与整理、地理多元流网络构建与结构识别、地理多元流网络演化分析、地理多元流网络关联分析。然后,分别对国际关系流网络、国际贸易流网络、全球航班流网络、全球人口移动流网络的相关研究进行综述分析,并结合示例介绍了其研究思路。此外,进一步综述分析了地理多元流关联分析的相关研究并提出了研究思路。本文为全球尺度地理多元流网络研究提供了一套研究框架和思路,并为国际关系、国际贸易、航空交通、人口移动等全球性问题研究提供参考,有望为发展基于“流”的时空分析方法做出基础性贡献。 相似文献
12.
介绍尼尔映射函数(NMF)、维也纳映射函数(VMF1)和全球映射函数(GMF)3种常用映射函数,讨论评估GPS基线质量的2个指标--基线重复性和平均值的标准偏差。根据中国境内IGS站的观测数据,基于GAMIT软件的数据处理结果,研究3种映射函数对GPS基线重复性和平均值标准偏差的影响。结果表明,在进行GPS基线处理时,动态映射函数的解算精度比经验映射函数要高,其中VMF1模型在解算基线重复性时结果更好,而GMF模型在计算平均值的标准偏差时效果更佳。 相似文献
13.
Estimating time-based instantaneous total mortality rate based on the age-structured abundance index 总被引：1，自引：0，他引：1
王迎宾 《中国海洋湖沼学报》2015,33(3):559-576
The instantaneous total mortality rate(Z) of a fish population is one of the important parameters in fisheries stock assessment. The estimation of Z is crucial to fish population dynamics analysis,abundance and catch forecast,and fisheries management. A catch curve-based method for estimating time-based Z and its change trend from catch per unit effort(CPUE) data of multiple cohorts is developed. Unlike the traditional catch-curve method,the method developed here does not need the assumption of constant Z throughout the time,but the Z values in n continuous years are assumed constant,and then the Z values in different n continuous years are estimated using the age-based CPUE data within these years. The results of the simulation analyses show that the trends of the estimated time-based Z are consistent with the trends of the true Z,and the estimated rates of change from this approach are close to the true change rates(the relative differences between the change rates of the estimated Z and the true Z are smaller than 10%). Variations of both Z and recruitment can affect the estimates of Z value and the trend of Z. The most appropriate value of n can be different given the effects of different factors. Therefore,the appropriate value of n for different fisheries should be determined through a simulation analysis as we demonstrated in this study. Further analyses suggested that selectivity and age estimation are also two factors that can affect the estimated Z values if there is error in either of them,but the estimated change rates of Z are still close to the true change rates. We also applied this approach to the Atlantic cod(G adus morhua) fishery of eastern Newfoundland and Labrador from 1983 to 1997,and obtained reasonable estimates of time-based Z. 相似文献
14.
清代自康熙年间开始 ,我国在另有所图的西方传教士的参与下 ,进行了史无前例的全国地图测绘工作 ,取得了辉煌的测绘科技成就 ,但由于当时的闭关主义、科技政策、文化传统、价值观念等因素的影响 ,导致了中国社会错失追赶西方的历史机遇 相似文献
15.
�������ӳٸ�����ͶӰ�������о� 总被引：2，自引：1，他引：1
????????????????????е?????????????????????????????????????????????????????????????塣?о??????е??????????????????????????????SCIGN??PBO??IGS?е??????????GPS?????????????GAM IT???????????????????????????з??????????????????Niell??GMF???????????GMF??????????????????á? 相似文献
16.
利用经验模态分解在处理非线性、非平稳信号以及人工神经网络可以较好地处理非线性问题的优点,通过经验模态分解把加入噪声的仿真信号分解成几个本征模态函数分量和一个趋势项,在分解过程中采用两种方法处理端点效应问题,结果表明两种方法都能很好的解决端点问题,然后对每个分量分别运用径向基函数神经网络进行预测,并重构出最后的预测结果。与不经EMD处理直接运用神经网络进行预测及真实数据进行对比,结果表明,相对于直接预测,该方法具有更好的预测效果。 相似文献
17.
聂建亮 《大地测量与地球动力学》2008,28(3):87-91
???????????????????????????????UKF?????????????÷??????????????????Unscented Kalman????????????????????????????????????Э????????????????????Kalman?????????????Kalman?????Unscented Kalman??????????????????????UKF????????????????????????????? 相似文献
18.
以Google Earth为代表的第一代数字地球平台,利用球面剖分瓦片,构建了2.5维静态的数字地球表面,实现了地表空间数据的集成、建模和应用,但没有涉及地表上下的空间。本文阐述了球体大圆弧QTM八叉树剖分的规则、瓦块体系的几何特征及其编码原理,设计并实现了瓦块编码到空间直角坐标之间的互换算法,并利用C++和OSG等主流语言,构建了真三维数字地球可视化平台的雏形框架;实现了球面和球体的任意剖分、地表上下空间实体的可视化建模及简单三维空间分析。初步展示了球体瓦块的新一代数字平台在天地一体化空间大数据集成、管理、建模与应用中的优势及前景。研究表明,球体大圆弧QTM八叉树网格,具有简单、规整、几何特征明晰、适宜作为全球离散空间的坐标基准,利于空间实体建模与可视化等特点,可作为构建新一代数字地球平台的数据模型基础。 相似文献
19.
利用长城站、中山站及周边13个IGS站2018年的观测数据,对比分析不同卫星截止高度角、对流层映射函数和全球海潮模型对GNSS坐标精度的影响。结果表明,截止高度角设为7°时,GNSS坐标解算精度最优,随着截止高度角的增大或减小,精度逐渐降低;采用VMF3模型解算的双差定位精度优于NMF、GMF和VMF1模型,VMF3模型解算的精密单点定位精度与GMF和VMF1模型相当;海潮负荷对GNSS坐标解算的影响与坐标方位有关,高程方向可达cm级,选用不同的海潮模型解算的GNSS坐标差异可忽略不计。 相似文献
20.
Major Function Oriented Zone: New method of spatial regulation for reshaping regional development pattern in China 总被引：5，自引：2，他引：3
Newest planning methods implemented by Chinese government are promoting a coordinated regional development and shaping an orderly spatial structure by applying the regulation of territorial function. This article analyzes the problems of spatial planning and regional strategy caused by the wrongly-set primary goal of economic development; it states that the three-fold objective of competitiveness, sustainability, and welfare fairness shall be the principal for China to implement the spatial regulation in the new era; it discusses about theoretical thoughts and technology framework of conducting the ′Major Function Oriented Zone′ based on their different major functions that each region plays in urbanization and industrialization, ecological constructions, grain productions, and protection of natural and cultural heritages; it introduces the new concept of ′Major Function Oriented Zone′ that include the major functions category, the stereo regional equilibrium mode, the two-level zoning specification, and the territorial development intensity; it offers a zoning scheme that defines development-optimized and development-prioritized zones as regions with massive urbanization and industrialization, development-restricted zones as ecological constructing or grain producing regions, development-prohibited zones as natural and cultural heritage protecting regions; and finally it addresses the main obstacle for implementing ′Major Function Oriented Zone′, which is the institutional arrangement of the supreme goal of high GDP growth rate that is currently being implemented. 相似文献