WGS-84&CGCS2000坐标基准转换参数的初步求取     

张清华  王源  曾京  孙阳阳  高磊 《测绘与空间地理信息》2015,(5)

针对WGS-84CGCS2000坐标基准差异问题,分析了用于估计基准转换参数的Bursa模型及其求解方法,初步尝试求取WGS-84CGCS2000的坐标基准转换参数。算例采用了中国区域内含有CGCS2000坐标值,同时安装有GPS接收机的21个观测站,并针对点位的区域分布问题,提出利用重心化的Bursa模型求解转换参数的思路,且得到一组较好的转换结果。  相似文献   

基于引力可达性的公共服务设施公平性分析模型——以福建长汀为例   总被引：1，自引：0，他引：1  

杨钦宇  徐建刚 《测绘与空间地理信息》2015,(6):48-51

公共服务设施的完善配套已成为社会文明进步的标志,其空间分布的公平程度深刻影响着城市居民的居住环境和生活质量。本文引入了威布尔的引力模型,借助Arc GIS软件平台,尝试构建基于引力可达性指数的公共服务设施公平性分析模型,并以福建长汀为例进行了实证研究,以期为公共服务设施规划提供实用的分析方法和技术支撑。  相似文献   

关联概率密度加权重力异常UKF滤波匹配导航算法     

王伟  李姗姗  邢志斌  曲政豪  郑伟 《测绘科学技术学报》2015,(4)

无味卡尔曼滤波(UKF)是一种通过采样来近似非线性分布,从而对非线性问题进行次优估计的滤波方法。利用实时观测得到的重力异常以及航行区域参考重力异常图,可以建立基于重力异常的UKF滤波匹配导航算法,以此校正惯性导航系统的漂移误差。针对选取与UT变换相同权系数来求取预测观测值而可能导致求得的预测观测值为伪观测值的问题,提出了利用关联概率密度函数对采样观测值进行加权的重力异常UKF滤波匹配导航算法。通过对某实验区域的实验进行计算分析,结果表明,基于关联概率密度加权重力异常UKF滤波算法能够克服传统加权预测观测值带来伪观测信息的问题,将惯性导航系统经纬向漂移误差降低至1.1 n mile以内,均优干传统加权算法和纯惯性导航系统的定位精度。  相似文献   

采用弱基准和抗差估计的重力网平差     

赵德军  张敏利  王强  陈永祥 《测绘工程》2015,(1):25-27,32

以沿海某测区绝对重力和相对重力网数据处理为例,详细描述了弱基准重力网平差的方法,绝对重力和相对重力先验权的确定,用抗差等价权来调整相对重力的权、重力仪参数的取舍。结果表明,弱基准能有效地提高整网的精度;抗差估计能有效地探测并降低异常数据的权。重力点平均中误差为13.6×10-8 ms-2,偶然误差检验符合正态分布。  相似文献   

球近似艾黎-海斯卡宁均衡模型分析     

荣敏  周巍 《测绘科学》2015,(8)

针对传统的均衡重力异常方式基于平面近似,积分范围较小、计算公式的适用性受限、表征的信息量有限的问题,该文在球坐标下分析艾黎-海斯卡宁(Airy-Hesikanen)均衡模型。以计算点向径为半径,将地形分为布格球壳和粗糙地形两部分,计算其地形影响和均衡改正。在实验区,选用补偿深度21km、密度差0.678g/cm3的模型参数,采用该文公式和传统公式计算均衡重力异常,并比较分析其计算值。结果表明,以球近似Airy-Hesikanen均衡模型计算均衡重力异常值,在小积分范围以及平坦地区,与传统公式计算值的精度相当;但随着积分半径增加,球近似Airy-Hesikanen均衡模型计算值精度不断提高、变化更平缓,说明球近似AiryHesikanen均衡模型代替平面近似Airy-Hesikanen均衡模型应用于重力问题研究更为符合地球实际情况。  相似文献   

高山地区地形对重力测量的影响分析     

邓文彬  阿力甫·努尔买买提 《测绘科学》2015,40(7):3-7

针对高山地区地形改正研究的不足,文章以青藏高原为实例,利用快速傅里叶变换详细讨论了高山地区地形改正中质量柱模型与质量线模型对重力测量的影响。研究结果表明:青藏高原地区,地形对重力测量的影响达到毫伽量级;采用快速傅里叶变换计算地形改正时,其最佳计算阶数应为二阶;高山地区,采用质量柱模型与质量线模型进行地形改正的差异为0.1mGal量级。  相似文献   

2011日本东北大地震前震余震重力效应分析     

龚正  许才军 《测绘科学》2015,(12):59-62

针对2011年日本东北大地震(Tohoku-Oki地震)发生前后较短时间内的多次较大前震和余震和主震混在一起,不利于提取出主震同震信号的问题,该文利用弹性位错理论模拟计算了Tohoku-Oki地震一次较大前震和两次较大余震的同震重力变化,讨论了这3次地震单独和综合的重力效应,并与主震重力变化对比分析,认为这3次前震和余震引起的重力变化数值较大,影响范围广,会直接影响到Tohoku-Oki地震主震的同震重力信号提取,所以需要作为重要误差考虑。  相似文献   

A DIAGNOSTIC ANALYSIS OF AIR TEMPERATURE ANOMALY MODE OVER CHINA IN 2009/2010 WINTER BASED ON GENERALIZED EQUILIBRIUM FEEDBACK ASSESSMENT (GEFA) METHOD     

江志红  吴燕珠  刘征宇  温娜  赵灿 《热带气象学报(英文版)》2015,21(2):121-130

By using the observed monthly mean data over 160 stations of China and NCAR/NCEP reanalysis data, the generalized equilibrium feedback assessment(GEFA) method, combined with the methods of EOF analysis, correlation and composite analysis, is used to explore the influence of different SST modes on a wintertime air temperature pattern in which it is cold in the northeast and warm in the southwest in China. The results show that the 2009/2010 winter air temperature oscillation mode between the northern and southern part of China is closely related to the corresponding sea surface temperature anomalies(SSTA) and its associated atmospheric circulation anomalies. Exhibiting warming in Northeast China and cooling in Southwest China, the mode is significantly forced by the El Nio mode and the North Atlantic SSTA mode, which have three poles. Under the influence of SSTA modes, the surface northerly flow transported cold air to North and Northeast China, resulting in low temperatures in the regions. Meanwhile, the mid-latitude westerlies intensify and the polar cold air stays in high latitudes and cannot affect the Southwest China, resulting in the warming there.  相似文献   

IMPACT OF SSTA OF SOUTHERN HEMISPHERE ON FLOOD SEASON PRECIPITATION ANOMALIES IN YUNNAN     

杨竹云  杨素雨  严华生  张瑾文 《热带气象学报(英文版)》2015,21(3):255-264

Based on the reanalysis data of monthly mean global SST and wind from the NCEP/NCAR and the observation data of rain seasons in 124 stations of Yunnan province from 1961 to 2006, we applied the analytical methods of correlation analysis and composite analysis and a significance testing method to two sets of samples of average differences. The goal is to investigate into the influence of the Southern Hemispheric (SH) SST on the summer precipitation in Yunnan from January to May so as to identify the key time and marine regions. Physical mechanisms are obtained by analyzing the influence of sea level wind and the key marine regions on the precipitation during Yunnan’s rain season. Results show that there is indeed significant relationship between the SST in SH and summer precipitation in Yunnan. The key areas for influencing the summer precipitation are mainly distributed in a region called “West Wind Drift” in the SH, including the Southeast Indian, southern Australia, west coast of eastern Pacific off Chile, Peru and the southwest Atlantic Magellan. Besides, the most significant marine region is the west coast of Chile and Peru (cold-current areas of the eastern Pacific). Diagnostic analysis results also showed that monsoons in the Bay of Bengal, a cross-equatorial flow in the Indian Ocean near the equator and southwest monsoon in India weaken during the warm phase of the Peruvian cold current in the eastern Pacific. Otherwise, they strengthen.  相似文献   

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叶周润  柳林涛 《大地测量与地球动力学》2015,35(1):45-49

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