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201.
GZSD—1606型数字强震记录仪与分析系统的研制   总被引:3,自引:0,他引:3  
强震观测是地震工程研究的一项基础性工作,它为地震动特性研究和工程结构抗震设计提供定量数据和理论依据。本文详细介绍了一种新型数字强震记录仪与分析系统的设计思想、特点,技术指标,同时给出了测试数据和实验曲线。  相似文献   
202.
对地震预测研究的信心的科学基础   总被引:3,自引:0,他引:3  
结合目前围绕地震预测问题的讨论,文章论述了对地震预测研究的信心的科学基础,指出地震预测研究在科学上是有意义的,地震预测研究最突出的困难是观测的限制,目前科学的发展为向地震预测问题发起新的冲击创造了条件。  相似文献   
203.
杨戟  曹逸庭 《天文学报》1998,39(3):333-336
用研制的全自动辐射计在97.8GHz上测量南京市内大气的不透明度以及这种不透明度随时间的变化.辐射计记录大气在不同天顶高度的辐射温度,由此测出天顶方向的大气不透明度。在56小时的测量时间内,取得了1400多组数据,拟合得到了在观测时段内天顶方向的大气不透明度在0.2至0.7之间,典型值为0.4,表明测试地点的大气条件允许进行3mm波段的射电天文观测.由于在工作频段内大气不透明度的主要来源是对流层水汽的吸收,测量的不透明度可用来直接反映大气内水汽的含量,并实时校准大气吸收.  相似文献   
204.
裴春传  曾琴 《天文学报》1998,39(1):103-105
使用紫金山天文台青海观测站13.7米毫米波射电望远镜,于1996年12月10日至1997年1月2日和1997年3月25日至1997年4月4日对海尔-波普彗星的CO分子J=1—0转动跃迁谱线(频率为115.27120GHz)进行了观测.观测谱线表明,CO分子相对于地心的速度比彗星整体相对于地心的速度要小些,即有蓝移现象.这反映了CO分子是由该彗星迎着太阳的面以一定的速度产生出来的.从观测谱线中还初步估算了该彗星CO分子的产生速率.  相似文献   
205.
The current and conventional fault-crossing short baseline measurement has a relatively high precision, but its measurement arrays usually fail to or cannot completely span major active fault zones due to the short length of the baselines, which are only tens to 100 meters. GNSS measurement has relatively low resolution on near-fault deformation and hence is not suitable for monitoring those faults with low motion and deformation rates, due to sparse stations and relatively low accuracy of the GNSS observation. We recently built up two experimental sites on the eastern boundary of the active Sichuan-Yunnan block, one crossing the Daqing section of the Zemuhe Fault and the other crossing the Longshu section of the Zhaotong Fault, aiming to test the measurement of near-fault motion and deformation by using fault-crossing arrays of one-kilometer-long baselines. In this paper, from a three-year-long data set we firstly introduce the selection of the sites and the methods of the measurement. We then calculate and analyze the near-field displacement and strain of the two sites by using three hypothetical models, the rigid body, elastic and composed models, proposed by previous researchers. In the rigid body model, we assume that an observed fault is located between two rigid blocks and the observed variances in baseline lengths result from the relative motion of the blocks. In the elastic model, we assume that a fault deforms uniformly within the fault zone over which a baseline array spans, and in the array baselines in different directions may play roles as strainmeters whose observations allow us to calculate three components of near-fault horizontal strain. In the composed model, we assume that both displacement and strain are accumulated within the fault zone that a baseline array spans, and both contribute to the observed variances in baseline lengths. Our results show that, from the rigid body model, variations in horizontal fault-parallel displacement component of the Zemuhe Fault at the Daqing site fluctuate within 3mm without obvious tendencies. The displacement variation in the fault-normal component keeps dropping in 2015 and 2016 with a cumulative decrease of 6mm, reflecting transverse horizontal compression, and it turns to rise slightly(suggesting extension)in 2017. From the elastic model, the variation in horizontal fault-normal strain component of the fault at Daqing shows mainly compression, with an annual variation close to 10-5, and variations in the other two strain components are at the order of 10-6. For the Longshu Fault, the rigid-body displacement of the fault varies totally within a few millimeters, but shows a dextral strike-slip tendency that is consistent with the fault motion known from geological investigation, and the observed dextral-slip rate is about 0.7mm/a on average. The fault-parallel strain component of the Longshu Fault is compressional within 2×10-6, and the fault-normal strain component is mainly extensional. Restricted by the assumption of rigid-body model, we have to ignore homolateral deformation on either side of an observed fault and attribute such deformation to the fault displacement, resulting in an upper limit estimate of the fault displacement. The elastic model emphasizes more the deformation on an observed fault zone and may give us information about localizations of near-fault strain. The results of the two sites from the composed model suggest that it needs caution when using this model due to that big uncertainty would be introduced in solving relevant equations. Level surveying has also been carried out at the meantime at the two sites. The leveling series of the Daqing site fluctuates within 4mm and shows no tendency, meaning little vertical component of fault motion has been observed at this site; while, from the rigid-body model, the fault-normal motion shows transverse-horizontal compression of up to 6mm, indicating that the motion of the Zemuhe Fault at Daqing is dominantly horizontal. The leveling series of the Longshu site shows a variation with amplitude comparable with that observed from the baseline series here, suggesting a minor component of thrust faulting; while the baseline series of the same site do not present tendencies of fault-normal displacement. Since the steep-dip faults at the two sites are dominantly strike-slip in geological time scale, we ignore probable vertical movement temporarily. In addition, lengths of homolateral baselines on either side of the faults change somewhat over time, and this makes us consider the existence of minor faults on either side of the main faults. These probable minor faults may not reach to the surface and have not been identified through geological mapping; they might result in the observed variances in lengths of homolateral baselines, fortunately such variations are small relative to those in fault-crossing baselines. In summary, the fault-crossing measurement using arrays with one-kilometer-long baselines provides us information about near-fault movement and strain, and has a slightly higher resolution relative to current GNSS observation at similar time and space scales, and therefore this geodetic technology will be used until GNSS networks with dense near-fault stations are available in the future.  相似文献   
206.
??10???????FG5-112?????????????й???????????????????о?????嶯??????????????????????68??????????ι????????????С??2??10 -8 ms -2???????????????????????С?????????????;????????????????????????????????????仯?????1??10 -8 ms -2 /a??????????λ???????-0.38 cm/a;??????????λ?仯??????????????????????????????  相似文献   
207.
山东地壳运动GPS观测网的建设与初步结果分析   总被引:2,自引:2,他引:0  
简述山东地壳运动GPS观测网的建设和数据处理的基本方法,并对系统所得的初步结果进行分析,分析表明,该系统可产出连续、高精度的GPS基准站三维坐标及基线数据,可为地震监测和地壳运动的科学研究提供良好的GPS数据素材。  相似文献   
208.
???????????????????????????????????????????????????????????????????????ж?λ?????????????????????????????????Σ??????λ?????????????????????????????????????????????μ???????????????б???????????????????????????????ú???????????????????????????????????????Ч?????б??????????????????ò??ù??????о????λ???λ?????  相似文献   
209.
依据JJF1059.1-2012《测量不确定度评定与表示》,针对自动气象站各要素传感器的测量误差会随时间、温度等环境因素的变化而发生漂移.为确保观测数据的准确、可靠,以CP340恒温恒湿箱为湿度发生环境、采用英国michell公司的Optidew Vision精密露点仪为标准器,介绍了利用HMP155A温湿度传感器进行湿度测量不确定度评定的一般方法和详细步骤.最后给出一个评定实例,在温度为22℃和40℃,相对湿度为30% RH~75%RH时,通过对测量不确定度的各分量进行分析和计算,得到HMP155A温湿度传感器测量结果的扩展不确定度分别为1.50%和1.46%.  相似文献   
210.
围海造陆工程泄水口悬浮物扩散规律分析   总被引:1,自引:1,他引:0  
掌握围海造陆工程泄水口悬浮物扩散规律,对保护海洋水环境质量具有重要意义。选取围海造陆工程泄水口为研究对象,基于泥沙对流扩散方程,推求出泄水口悬浮物扩散平面二维分析解表达式。开展现场观测,确定泄水口源强取值,并对泄水口悬浮物扩散进行理论计算和分析。研究结果显示,围海造陆工程施工后期,泄水口悬浮物流失非常严重。泄水口附近水域出现的最大悬浮物浓度主要由源强的大小来决定,悬浮物扩散范围主要由流速的大小来控制。  相似文献   
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