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991.
陈吴敏 《国土资源导刊(湖南)》2015,(1):80-83
本文结合湖南省地理国情普查成果质量检查与验收的实际工作情况,根据相关标准规范,对改进和细化后的地理国情普查成果检查验收流程进行总结阐述。 相似文献
992.
������ģ��EGM2008��EGM96���й������ıȽ������� 总被引:4,自引:0,他引:4
?????й?854??GPS/?????????EGM2008??EGM96?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????289??GPS/??????н????????????????????????????????????????????????EGM2008???EGM96???????á? 相似文献
993.
���ϵ�������Ӧ������ǿ����ϵ�о� 总被引:1,自引:0,他引:1
???????????????????????????鹹???????????????????????о?????????????????????GPS?????????????????????????,?????????????????????????????????????????????????????6??????????????????????????????????????????????????????????????????????????????н???????, ??????????????3????????Σ?????? 相似文献
994.
����ARģ�͵��Ϻ������������Ԥ����� 总被引:1,自引:1,他引:1
????AR?????????????????????????????????????AIC?????AR????????????????????,AR??4?????????????????????AR(4)???????????δ??10??????????????????? 相似文献
995.
利用冀鲁豫测网的流动重力5期观测成果,探讨了重力场变化与封丘地震的关系。研究发现:冀鲁豫交界地区的重力点值在封丘地震前后出现了下降-上升-下降的变化过程,较好地对应了封丘ML4.8地震孕育 发震 震后调整的过程。该重力变化可能是封丘地震的异常反映。 相似文献
996.
We performed a karyotype analysis on four species from Phylum Nemertea using regenerating somatic cells. Two palaeonemertean species, Cephalothrix hongkongiensis and Cephalothrix sp., had the same chromosome number (2n=28), but different karyotypes (16 m+10 sm+2 st, NF=54 and 22 m+4 sm+2 st, NF=54, respectively). The karyotypes of the two heteronemerteans, Notospermus geniculatus and Ramphogordius sanguineus were 2n=38, 30 m+6 sm+2 sm/st (NF=76/74) and 2n=56, 48 m+4 sm+4 sm/st (NF=112/108), respectively. 相似文献
997.
Using wavelet analysis, regression analysis and the Mann-Kendall test, this paper analyzed time-series (1959–2006) weather
data from 23 meteorological stations in an attempt to characterize the climate change in the Tarim River Basin of Xinjiang
Uygur Autonomous Region, China. Major findings are as follows: 1) In the 48-year study period, average annual temperature,
annual precipitation and average annual relative humidity all presented nonlinear trends. 2) At the 16-year time scale, all
three climate indices unanimously showed a rather flat before 1964 and a detectable pickup thereafter. At the 8-year time
scale, an S-shaped nonlinear and uprising trend was revealed with slight fluctuations in the entire process for all three
indices. Incidentally, they all showed similar pattern of a slight increase before 1980 and a noticeable up-swing afterwards.
The 4-year time scale provided a highly fluctuating pattern of periodical oscillations and spiral increases. 3) Average annual
relative humidity presented a negative correlation with average annual temperature and a positive correlation with annual
precipitation at each time scale, which revealed a close dynamic relationship among them at the confidence level of 0.001.
4) The Mann-Kendall test at the 0.05 confidence level demonstrated that the climate warming trend, as represented by the rising
average annual temperature, was remarkable, but the climate wetting trend, as indicated by the rising annual precipitation
and average annual relative humidity, was not obvious. 相似文献
998.
?????????????????????????????????????????????????????????????з???????????????????????????????????????????????????????????????????????С????????????????÷????????????????????????????????????У???????????????????????? 相似文献
999.
YANG Ying-hui CHEN Qiang LIU Guo-xiang Li Zhi-lin CHENG Hai-qin Liu Li-yao 《山地科学学报》2013,10(5):790-800
In order to overcome the limitation of cross correlation coregistration method for Synthetic Aperture Radar(SAR) interferometric pairs with low coherence,a new image coregistration algorithm based on Fringe Definition Detection(FDD) is presented in this paper.The Fourier transformation was utilized to obtain spectrum characteristics of interferometric fringes.The ratio between spectrum mean and peak was proposed as the evaluation index for identifying homologous pixels from interferometric images.The satellites ERS-1/2 C-band SAR acquisitions covering the Yangtze River plain delta,eastern China and ALOS/PALSAR L-band images over the Longmen Shan mountainous area,southwestern China were respectively employed in the experiment to validate the proposed coregistration method.The testing results suggested that the derived Digital Elevation Model(DEM) from FDD method had good agreement with that from the cross correlation method as well as the reference DEM at high coherence area.However,The FDD method achieved a totally improved topographic mapping accuracy by 24 percent in comparison to the cross correlation method.The FDD method also showed better robustness and achieved relatively higher performance for SAR image coregistration in mountainous areas with low coherence. 相似文献
1000.
????IGS???????GIM???????????????TEC??Total Electron Content?????????2007-2011???????й??????????17???M??≥6.0????????????????????PCA??Principal Component Analysis?? ???????????TEC??????????????????????????б???????????PCA??????????????????????????????????????????£???????????????TEC????????????????????????????0~5?? 相似文献