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61.
针对前兆设备实时监控过程中动态实时信息的传输问题,提出了一种实现前兆设备动态报警、动态监控功能的解决方案,并在实际设备和网络环境中进行了应用,达到了预期的目标。  相似文献   
62.
近年来我国布设的强震动观测结构台阵越来越多,并在数次地震中捕获了一批宝贵的观测记录,这些记录既是对应用日益广泛的结构数值模拟结果的检验和参数标定的依据,也是结构健康监测的重要数据。本文选取昆明防灾减灾中心大楼观测台阵捕获的3次中远场小震记录作为研究对象,对比ANSYS结构数值模拟和观测值之间在时程以及谱特性等方面的响应差别,证明了在弹性范围下二者结果具有较好的一致性。最后,基于观测记录,采用高效简单的经验谱比法进行了结构模态参数快速识别,3次地震下的自振频率计算结果相对稳定,与数值建模计算结果的差值可控制在0.17Hz以内。  相似文献   
63.
从国际地磁台站分布、地磁信息节点分布、地磁观测技术指标、数据产品及服务应用等5个方面介绍了国际地磁台网的发展现状。通过综合分析,得出地磁场和空间环境的全球性精细化监测及预报已经成为地球科学家关注的焦点。在此基础上,从4个方面预测了国际地磁台网未来发展趋势,以期为我国开展相关工作提供参考和借鉴。  相似文献   
64.
A Multi-Application Solar Telescope (MAST) is proposed to be installed at the lake site (Lake Fatehsagar) of Udaipur Solar Observatory (USO) in India. The lake site Observatory of USO is located on a small island in the middle of the lake. To determine the optimum size of the MAST (for use with an adaptive optics system), it was decided to quantify the seeing conditions prevailing at the lake site during the different months of the year. For this purpose, we have used short-exposure (3 ms) high-resolution Hα (6563 Å) images (spatial scale of ~0.55 arc sec per pixel) of the Sun taken in burst mode with the 15-cm refractor Spar telescope located at the lake site of USO. Spectral ratio technique as reported by von der Lühe (1984, J. Opt. Soc. Am. A1, 510) has been used to estimate the Fried’s parameter (r 0) at this site, which gives the quantitative measure of astronomical seeing. This study has been carried out daily on an hourly basis during 4:30?–?10:30 UT over the months January?–?June of the years 2005 and 2006 to understand the diurnal and seasonal variations in r 0 at this site. It is noteworthy that the lake was almost dry during the observing period in 2005, while it overflowed during our observations in 2006 because of abundant monsoon rains. The seeing in the presence of water shows improvement in r 0 by about 1.0 cm with respect to the previous year’s dry condition and mean r 0 varies between 4.0 and 4.5 cm as evident from the data obtained between January and June, 2006.  相似文献   
65.
台站观测是实现防震减灾三大工作体系任务的基础。本文结合台站和地震系统期刊的基本情况,概述了创办《地学台站观测》这种面向台站的科技期刊的社会需求和科学需求,从中国地震局发展战略的层次上初步探讨了创办这种期刊的意义。  相似文献   
66.
For most of the ultra-high-energy cosmic ray (UHECR) experiments and projects (HiRes, AUGER, TA, JEM-EUSO, TUS, …), the detection technique of extensive air showers is based, at least, on the measurement of the air-fluorescence-induced signal. The knowledge of the fluorescence-light yield (FLY) is of paramount importance for the UHECR energy reconstruction. The MACFLY experiment was designed to perform absolute measurements of the air FLY and to study its properties. Here, we report the result of measurement of dry-air FLY induced by 50 GeV electromagnetic showers as a function of the shower age and as a function of the pressure. The experiment was performed at CERN using a SPS-electron-test-beam line. The result shows the air FLY is proportional to the energy deposited in air (Ed). The ratio FLY/Ed and its pressure dependence remain constant independently of shower age, and more generally, independently of the excitation source used (single-electron track or air shower).  相似文献   
67.
The Southern U.S. Piedmont ranging from Virginia to Georgia underwent severe gully erosion over a century of farming mainly for cotton (1800s–1930s). Although tree succession blanketed much of this region by the middle 20th century, gully erosion still occurs, especially during wet seasons. While many studies on gully erosion have focused on soil loss, soil carbon exchange, and stormwater response, the impacts on soil moisture, groundwater, and transpiration remain under-studied. Using a newly developed 2D hydrologic model, this study analyzes the impacts of gully erosion on hillslope hydrologic states and fluxes. Results indicate that increases in gully incision lead to reduction in groundwater table, root zone soil moisture, and transpiration. These reductions show seasonal variations, but the season when the reduction is maximum differs among the hydrologic variables. Spatially, the impacts are generally the greatest near the toe of the hillslope and reduce further away from it, although the reductions are sometimes non-monotonic. Overall, the impacts are larger for shallow gully depths and diminish as the incision goes deeper. Lastly, the extent of impacts on a heterogeneous hillslope is found to be very different with respect to a homogeneous surrogate made of dominant soil properties. These results show that through gully erosion, the landscape not only loses soil but also a large amount of water from the subsurface. The magnitude of water loss is, however, dependent on hydrogeologic and topographic configuration of the hillslope. The results will facilitate (a) mapping of relative susceptibility of landscapes to gullying, (b) understanding of the impacts of stream manipulations such as due to dredging on hillslope eco-hydrology, (c) prioritization of mitigation measures to prevent gullying, and (d) design of observation campaigns to assess the impacts of gullying on hydrologic response.  相似文献   
68.
We present a dataset on to the Arc-Isère long-term environmental research observatory, which is part of the Rhône Basin Long Term Environmental Research Observatory. This alpine catchment located in the French Alps is characterized by high Suspended Particulate Matter (SPM) in anthropogenized valleys. Suspended Sediment Concentrations (SSC) naturally observed in the river are very high, ranging from a few tens of milligrams per litre at low flow to tens of grams per litre during major natural hydrological events (floods, debris flows) or river dam hydraulic flushes. One research objective related to this site is to better understanding the SSC dynamics along the river using a system of nested catchments (Arvan, Arc, and Isère) in order to assess both temporal and spatial dynamics. The data allow the quantification of fine sediment yields and also the evaluation of possible morphological changes due to fine sediment deposition or resuspension. Additionally, the observatory database support studies on contaminants (either dissolved or particulate contaminants). Our monitoring includes six stations with high frequency (2–30 min) streamflow, SSC measurement using turbidity sensors, and associated automatic sampling. Discharge is measured via water level measurements and a rating curve. The oldest station (Grenoble-campus) started recording discharge and concentration data from April 2006 while others stations were built between 2009 and 2011. Data are available in an online data website called ‘Base de Données des Observatoires en Hydrologie’ (Hydrological observatory database, https://bdoh.irstea.fr/ARC-ISERE/ ) with a DOI reference for the dataset. The hydrological and sediment transport time series are stored, managed and made available to a wide community with unfettered access in order to be used at their full extent. This database is used as a data exchange tool for both scientists and operational end-users and there is an associated online tool to compute integrated fluxes.  相似文献   
69.
通过分析海底观测仪器的数据特点,探索了基于MATCOM的Matlab混合编程来实现海底实时观测数据可视化的方法。采用ADO.NET技术远程访问SQL Server数据库中的当日日志表以获取海底实时观测数据,利用了VC++.NET的友好交互开发环境和Matlab强大的绘图函数,实现对海底物理、化学、能源等实时观测数据的图...  相似文献   
70.
为推进地震数据共享,构建了蒙城地球物理国家野外科学观测站地震数据共享服务平台,目的是为安徽省防震减灾和国民经济建设提供数据服务,增强地震部门社会服务功能。平台提供的多元化的地震数据共享服务,将进一步提升野外站整体科研水平。  相似文献   
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