应用数字近景摄影测量提取岩体裂隙迹长信息方法研究

针对传统以皮尺为主要工具的岩体裂隙迹长测量方法精度及效率较低、尤其是遇有危险场地不能遥测等缺点,研究应用数字近景摄影测量的方法获取岩体裂隙迹长信息,以普通非量测数码相机为主要工具,以JX-4A数字摄影测量工作站为依托进行信息处理,可以快速获取隧道施工掌子面裂隙迹线图。经实验比较分析,数字近景摄影测量方法获取岩体裂隙信息在精度和效率方面都优于传统方法。     

基于活动控制的岩体结构面几何信息快速获取

在应用数字近景摄影测量进行岩体结构面几何信息快速获取时,需要在岩体上布设一定数量的控制点,但特殊区域岩体（隧道、硐室、采石场）的结构面相对破碎、特征点极不明显,并且受施工进度的影响,无法在岩体上布设控制点。针对这一问题,本文应用自行设计的活动控制架,在控制架上布设28个控制点,将控制架和岩体结构面一起摄影,然后在VZ（VirtuoZo）工作站上进行内业解译,获取岩体结构面上特征点的空间坐标,再依据所给产状公式获取结构面信息。以净月二采石场岩体边坡为研究对象,进行了活动控制架安装与检验、外业数据采集与内业数据处理等工作;同时基于误差理论点位精度评定方法,对解译的控制点坐标与岩体结构面产状（倾向、倾角）同实测值对比并进行精度分析。结果表明,该方法测量的岩体结构面产状中误差：m_倾向=±4°,m_倾角=±3°,满足岩体结构面精度测量要求。     

宁波地震台地倾斜模拟与数字观测对比分析

通过对宁波台地倾斜数字VS垂直摆与模拟JB水平摆倾斜仪2002年一年时间的并行观测和研究,认为在观测资料的连续性、稳定性、可靠性和观测精度上,VS垂直摆倾斜仪明显优于JB水平摆倾斜仪;在数据传输上,数字化仪器实现了远距离快速传输,有利于及时捕捉地震的短临信息,有利于资料共享。     

钻孔环境在钻孔地形变观测中的作用

正式提出了钻孔环境问题,它对于钻孔形变仪器的安装顺利与否,资料质量好坏,资料的使用价值等,有着重大的影响。对钻孔环境的内涵作了初步的讨论,如钻孔的倾斜,钻孔的畸变,钻孔穿过破碎带和裂隙及钻孔的历史背景等。     

Eddy flux corrections for CO2 exchange in broad-leaved Korean pine mixed forest of Changbai Mountains

Based on analysis of mechanisms causing energy no-closure and nocturnal low fluxes issues for CO2 exchange studies by eddy covariance method, corrections were done with the raw data sets obtained from Changbai Mountains forest flux site, to evaluate the impacts of sonic anemometer tilt, frequency response limitations and advection on estimation of CO2 exchange, respectively. The results show that the planar fit coordinate transforming method is superior to the streamline coordinate transforming method in tilt correction. The latter could cause a systematical underestimation of eddy fluxes relating with the angle of sensor and terrain tilt. The underestimation of CO2 and energy fluxes for frequency response limitations average 3.0% and 2.0% during daytime, respectively, which increase by 9.0% and 5.5% during nighttime, respectively. The corrections of frequency response limitations are closely related to atmospheric stability. The advection loss of CO2 fluxes is dominated by nocturnal vertical advection, which is at least 18% when the horizontal advection is neglected. It is suggested that more work be done to understand the characteristics of horizontal advection and turbulent eddies under a complexcircumstance.     

云南楚雄台水管倾斜仪潮汐因子变化与澜沧—耿马地震

本文对楚雄台水管倾斜仪1986年～1988年观测的数据,用莱柯拉兹方法初步进行了潮汐波分析。并对可能与澜沧—耿马地震有联系的异常情况进行了论述。     

大同─阳高6．1级地震太原台前兆异常

太原台１９８５年至１９９１年的地应力、地倾斜、连通管和地电阻率４种前兆手段的月均值具有明显的正弦形年变规律，且在年变背景上出现年变幅度的增大或减小。前３种手段还叠加有趋势性上升或下降。用差值法定量地消除年变以后，无震时段变化平稳，有震时段异常突出，较好地反映了大同一阳高地区的中强地震。     

张北6.2级地震前宝昌地震台的前兆异常研究

１９９８年１月１０日河北省张北６．２级地震前,距震中１００ｋｍ的内蒙古宝昌地震台石英倾斜仪ＮＳ分量自１９９６年７月出现向南倾斜的趋势异常,ＥＷ分量１９９７年８月向西倾斜的短期异常,并在地震发生前６天之内,倾斜仪固体潮曲线上出现多次阶跃式畸变,可能是张北６．２级地震的临震前兆。与此同时,该台站的地电阻率也在震前２．５个月出现短期异常。     

Quantification of braided river channel change using archival digital image analysis

Historical archives of grey‐scale river channel imagery are extensive. Here, we present and test a methodology to extract detailed quantitative topographic data from such imagery of sand‐bed rivers. Extracting elevation information from rivers is difficult as they are characterized by a low relative relief (<4 m); the area of interest may be spatially extensive (e.g. active channel widths >500 m in large braided rivers); the rate of change of surface elevation is generally low except in the vicinity of individual channel banks where the rate of change is very high; there is the complication that comes from inundation; and there may be an added complication caused by blockage of the field of view by vegetation. Here, we couple archival photogrammetric techniques with image processing methods and test these for quantification of sand‐bed braided river dynamics, illustrated for a 500 m wide, 3 km long reach of the South Saskatchewan River, Canada. Digital photogrammetry was used to quantify dry areas and water edge elevations. A methodology was then used to calibrate the spectral signature of inundated areas by combining established two media digital photogrammetric methods and image matching. This allowed determination of detailed depth maps for inundated areas and, when combined with dry area data, creation of complete digital elevation models. Error propagation methods were used to determine the erosion and deposition depths detectable from sequential digital elevation models. The result was a series of elevation models that demonstrate the potential for acquiring detailed and precise elevation data from any historical aerial imagery of rivers without needing associated calibration data, provided that imagery is of the necessary scale to capture the features of interest. We use these data to highlight several aspects of channel change on the South Saskatchewan River, including bar movement, bank erosion and channel infilling. Copyright © 2010 John Wiley & Sons, Ltd.     

海拉尔地震台SSQ-2I水平摆与VP垂直摆观测数据对比分析

基于SSQ-2I型数字石英水平摆与VP型垂直摆倾斜仪2种摆式倾斜仪不同的工作原理,对2018—2020年海拉尔地震台2套仪器的观测数据连续率与完整率、倾斜量年飘零与年变幅、数据观测精度、噪声水平、映震能力等进行对比分析,以对2套仪器的效能进行综合评价。结果表明,SSQ-2I水平摆仪器效能优于VP垂直摆。