我们在具有无质量标量场的(动态)爱因斯坦–钱恩–西蒙斯(ECS)理论的框架内,讨论广义相对论(GR)中NUT时空的推广。 这些配置渐近地接近NUT时空,并具有“电”和“磁”质量参数以及标量“电荷”的特征。 该解决方案可以通过分析和数值找到。 分析方法在爱因斯坦引力背景周围是微扰的。 我们的结果表明,ECS配置共享GR中NUT时空的所有基本属性。 但是,当考虑事件视界内的解时,我们发现与GR情况相反,时空曲率无限制地(显然)增长。
2024-03-23 14:23:59 356KB Open Access
1
简要介绍了EGM2008地球重力场模型,利用分布于我国东部平原地区,中部丘陵地带和西部高原山区的4个测量项目的数据,对EGM2008地球重力场模型的精度进行了分析,并对该模型在不同地形条件下的应用方法进行了探索。
2023-01-21 10:55:33 284KB 自然科学 论文
1
全球重力场模型下载 EGM2008.gfc重力场模型数据下载
2023-01-20 23:32:31 240.46MB EGM2008
1
XGM2019e is a combined global gravity field model represented through spheroidal harmonics up to d/o 5399, corresponding to a spatial resolution of 2’ (~4 km). As data sources it includes the satellite model GOCO06s in the longer wavelength area combined with terrestrial measurements for the shorter wavelengths. The terrestrial data itself consists over land and ocean of gravity anomalies provided by courtesy of NGA (identical to XGM2016, having a resolution of 15’) augmented with topographically derived gravity over land (EARTH2014). Over the oceans, gravity anomalies derived from satellite altimetry are used (DTU13, in consistency with the NGA dataset). The combination of the satellite data with the terrestrial observations is performed by using full normal equations up to d/o 719 (15’). Beyond d/o 719, a block-diagonal least-squares solution is calculated for the high-resolution terrestrial data (from topography and altimetry). All calculations are performed in the spheroidal harmonic domain. In the spectral band up to d/o 719 the new model shows over land a slightly improved behavior over preceding models such as XGM2016, EIGEN6c4 or EGM2008 when comparing it to independent GPS leveling data. Over land and in the spectral range above d/o 719 the accuracy of XGM2019e slightly suffers from the sole use oftopographic forward modelling; Hence, errors are increased in well-surveyed areas compared to models containing real gravity data, e.g. EIGEN6c4 or EGM2008. However, the performance of XGM2019e can be considered as globally more homogeneous and independent from existing high resolution global models. Over the oceans the model exhibits an improved performance throughout the complete spectrum (equal or better than preceding models).
2023-01-16 14:37:29 267.95MB 重力场模型 高分辨率
1
重力场模型 matlab 详细文件 有解释 很好懂 EGC12008的数据
1
作业要求:根据SGG-UGM-1重力场模型,取前360阶次,并考虑前四个正常引力位系数,计算全球区域(1°)和中国西部(5’)的引力位、大地水准面高、重力异常、重力扰动分布,并绘图呈现 代码功能:C#(VS 2015)编写,可以导入其它重力场模型,自定义阶次、格网间隔、区域范围等,用matlab的m_map包实现绘图
2022-12-01 21:05:28 80.91MB 物理大地测量学 测绘 武汉大学
1
根据积分方程法反演地球重力场的数学模型,利用GOCE卫星2009-11-02~2010-01-02共61d的精密轨道数据反演了几组地球重力场模型。结果表明,GOCE卫星轨道能有效提取地球重力场的长波信息,弥补了GOCE卫星重力梯度带宽的限制,在106阶次的大地水准面误差为±9.6cm,该阶次精度优于EIGENCHAMP03S及GRACE卫星两个月轨道反演地球重力场的精度,但由于两极空白,反演的带谐位系数精度偏低。联合GOCE及GRACE卫星轨道反演的模型在106阶次的大地水准面误差为士6.9cm,弥补丁G
2022-09-22 10:33:06 256KB 工程技术 论文
1
TU Graz开发的开源GNSS定位定轨程序Groops 官方服务器有时抽风,可从此处下载 自己做个备份,有需要的自取 源码地址:https://github.com/groops-devs/groops 示例文件+表文件地址:https://ftp.tugraz.at/outgoing/ITSG/groops/
2022-07-19 23:18:51 285.99MB gnss 定位 groops c++
1
这是用WebPython,即Vpython制作的“等效重力场”及"最高点速度"三维教学模型,您可以调节小球初速度,调节三维视角等。可以作为小球通过最高点的最小速度问题的教学模型,适用于高中物理教学。
根据重力场模型文件计算重力异常,大地水准面高,以及垂线偏差。
2022-05-28 14:21:15 35.2MB 重力场模型计算
1