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141.
本文围绕我国GPS空间定位网布测的目的意义、布网方案及相应的精度指标,施测中应考虑的观测技术和数据处理策略等有关技术问题展开了较深入的讨论,并指出了结合定位网布测应开展的几项基础研究。最后,就以上问题总结了作者们的基本观点,供有关方面参考。 相似文献
142.
吴素芹 《武汉大学学报(信息科学版)》1992,(3)
本文对GPS基线向量网的可靠性进行了探讨,提出了作为相关观测值的单个基线向量的可靠性指标和粗差检验方法,并通过对实测网和模拟网的计算与分析,得出了一些有关GPS基线向量网可靠性设计的建议和结论。 相似文献
143.
地下水位潮汐观测资料的Nakai预处理 总被引:1,自引:0,他引:1
推导了改进后的Nakai拟合法计算公式,利用改进后的Nakai拟合法,对山东商河、威海、莒南和兖州四口水井的观测数据进行预处理,然后对资料进行了调和分析。计算结果表明,经过这种方法预处理后的观测数据分析精度普遍得到提高。 相似文献
144.
现代野外观测和数据处理常常分开来研究,在理论的联系上它们应该是一个整体,而且应该把野外观测的高质量,作为正确实施数据处理的前提条件,在进行数据处理的时候,应该严谨对待其全过程的每一步骤。 相似文献
145.
146.
The remote sensing observational study for infrared radiation of rocks was proceeded during the loading on rocks until failure.
The major instruments used in experiments were transient spectrum apparatus, intelligent spectrum apparatus, infrared radiation
thermometer, infrared spectrum radiometer, and infrared thermal imaging system. The experiments for 26 kinds of rocks were
made. The studies show that infrared radiation temperature of rocks increases along with increasing of stress. The amplitude
of infrared radiation spectrum of rocks also increases along with increasing of stress. The observational results of infrared
thermal imaging of rocks are consistent with infrared radiation temperature. Before formation of major faults for some rocks,
the belt-shape thermal imaging of temperature anomaly displaies in position of future major faults. This study has led the
new technology of remote sensing into rock mechanics and tend to establish a new field in rock mechanics — remote sensing
rock mechanics (or remote sensing rock physics). The application of remote sensing rock mechanics in prediction of earthquake
and rock burst, and in measurement of stress field in rock mass is expected.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, Supp., 645–652, 1992.
Jin-Shen HAO, Ji-Han LI, Xiao-Hong LIU, Yi-Qiao ZHI, Jin-Kai ZHANG, Yong-Hong Lü, Yi LIU, Yun-Shen YU, He ZHANG, Quan-Quan
JI, Xiao-Fan ZHU and Ning CHEN took part in this work.
This subject is supported by the Chinese Joint Seismological Science Foundation (91006).
Work of Institute of Geophysics, SSB (93A0009). 相似文献
147.
An introduction to the
instrumonts to be used for solar radio observations in Beijing in Solar Cycle 23 is made
in this paper. They are 10cm solar radio telescope which has been used for a long time,and 1.0~2.0GHz,2.6~3.8GHz and 5.2~7.6GHz spectrometers. The former two spectrometers has
passed a test,showing
high guality,and the
5.2~7.6GHz one will
be in operation from 1999. It is believed that highl gualified data should be obtained in
the next solar cycle. 相似文献
148.
选取2015—2019年洱源水化站FD-105K与FD-125测氡仪对比观测资料,采用一阶差分、F检验、t检验等方法进行对比分析,结果显示:FD-125测氡仪测值总体偏低,且测量精度较低,数据离散程度较高;2套观测数据变化趋势一致性不理想,相关性较低,未通过F检验和t检验。综合分析认为,FD-125测氡仪暂时不能替代FD-105K测氡仪进行观测,需要增加震例对2套仪器的映震效能进行验证。 相似文献
149.
ABSTRACTWidespread forest fire events occurred in the foothills of North Western Himalaya during 24 April to 2 May 2016 (Event-1) and 20–30 May 2018 (Event-2). Their impacts were investigated on the distribution of pollutant gases ozone (O3), carbon monoxide (CO), and oxides of nitrogen (NOx) over Uttarakhand using simulations of Weather Research and Forecasting model coupled with chemistry (WRF-Chem) and in-situ observations of these gases over Dehradun, the capital of Uttarakhand. During Event-1, the observed CO mixing ratio over Dehradun increased from 25 April 2016 onwards, attained maximum (705.8 ± 258 ppbv) on 2 May 2016 and subsequently decreased. The rate of increase of daily baseline CO was 29 ppbv/day during HFAP (High Fire Activity Period). During Event-2, daily average concentrations of CO, O3, and NOx showed systematic increase over Dehradun during HFAP period. The rate of increase of CO was 9 ppbv/day, while it was very small for NOx and O3. To quantitatively estimate the influence of forest fire emissions, two WRF-Chem simulations were made: one with biomass burning (BB) emissions and other without BB emissions. These simulations showed 52% (34%) enhancement in CO, 52% (32%) enhancement in NOx, and 11% (9%) enhancement in O3 during HFAP for Event-1 (Event-2). A clear positive correlation (r = 0.89 for Event-1, r = 0.69 for Event-2) was found between ?O3 (O3with BB minus O3without BB) and ?CO (COwith BB minus COwithout BB), indicating rapid production of ozone in the fire plumes. For both the events, the vertical distribution of ?O3, ?CO, and ?NOx showed that forest fire emissions influenced the air quality upto 6.5 km altitude. Peaks in ?O3, ?CO, and ?NOx during different days suggested the role of varying dispersion and horizontal mixing of fire plumes. 相似文献
150.
提出了一种可用于下一代VLBI观测系统(VGOS)的双线极化条纹拟合方法。现有的VLBI观测模式采用的是右圆极化(RCP),而VGOS系统采用的是双线极化。本文方法包括校正和组合条纹拟合两部分。校正部分选择一颗强源作为参考源,分别得到不同极化方式下的通道时延及相位校正数据,用于目标源的校正。组合条纹拟合部分将4种极化分量的可见度数据组合成伪Stokes分量,通过搜索差分星位角使伪Stokes分量的幅值达到最大,从而获得最终的时延观测量。与单极化条纹拟合相比,组合极化获得的条纹具有更高的信噪比(SNR)及更小的条纹相位弥散度。 相似文献