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991.
992.
PCVSAT单收站各类故障分析与处理 总被引:2,自引:2,他引:0
自 PCVSAT(Personal Computer Very SmallAperture Terminal)单收站投入运行以来,有效提高了基层台站的预报业务现代化水平.作为地(市)级气象部门预报资料的主要接收渠道,其运行维护尤为重要. 相似文献
993.
利用W indow s操作系统中的超级终端检测、判断自动站采集器的状态,同时可对已缺测的正点数据进行补救。 相似文献
994.
【目的】为评估DSG1型和DSG5型国产降水现象仪在测量降水方面的性能。【方法】挑选鲁南地区降水过程、强度和持续时间较一致且相邻2个国家气象观测站不同型号的降水现象仪和自动气象站2017年9月—2020年8月5年降水观测资料,对比分析了这两种不同型号降水现象仪和自动气象站观测降水的差异。【结果】(1)两种降水现象仪和自动气象站观测的降水时间基本相同,但DSG1型和DSG5型比自动气象站分别偏多约2.2%、3.7%;(2)两种降水现象仪分钟降水量、小时降水量和日降水量都比自动气象站偏小;(3)在中等降水强度及以下,两种降水现象仪观测的降水量大小基本一致,但降水强度较大时,降水量大小不一致且分散;(4)两种降水现象仪与自动气象站的分钟、小时和日降水量差值百分比均值变化不同,说明其在测量降水方面性能略有差异。【结论】由于测量原理和时间及空间分辨率不同于自动气象站雨量计,这两种降水现象仪在观测业务中有着良好的表现,对降水开始和结束时刻记录的更早更准确。 相似文献
995.
Muhammad N.Mushtaq Muhammd Tahir Muhammd T.Iqbal Muhammd A.Shah Saleem Iqbal Talat Iqbal 《地震科学(英文版)》2021,34(2):114-122
Hindukush is an active subduction zone where at least one earthquake occurs on daily basis. For seismic hazard studies, it is important to develop a local magnitude scale using the data of local seismic network. We have computed local magnitude scale for Hindukush earthquakes using data from local network belonging to Center for Earthquake Studies (CES) for a period of three years, i.e. 2015–2017. A total of 26,365 seismic records pertaining to 2,683 earthquakes with magnitude 2.0 and greater, was used with hypocentral distance less than 600 km. Magnitude scale developed by using this data comes to be ML = logA + 0.929logr + 0.00298r – 1.84. The magnitude determined through formulated relation was compared with that of standard relation for Southern California and relation developed by the same authors for local network for Northern Punjab. It was observed that Hindukush region has high attenuation as compared to that of Southern California and Northern Punjab which implies that Hindukush is tectonically more disturbed as compared to the said regions, hence, seismically more active as well. We have calculated station correction factors for our network. Station correction factors do not show any pattern which probably owes to the geological and tectonic complexity of this structure. Standard deviation and variance of magnitude residuals for CES network determined using Hutton and Boore scale and scale developed in this study were compared, it showed that a variance reduction of 44.1% was achieved. Average of magnitude residuals for different distance ranges was almost zero which showed that our magnitude scale was stable for all distances up to 600 km. Newly developed magnitude scale will help in homogenization of earthquake catalog. It has been observed that b-value of CES catalog decreases when magnitude is calculated by using newly developed magnitude scale. 相似文献
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997.
网络RTK中几种实用技术的分析比较 总被引:5,自引:0,他引:5
针对网络RTK中采用的几种技术作出详尽的论述,在理论分析的基础上对各种技术的优缺点进行了比较。认为合理选取网络RTK中的实用技术能更好地发挥其可靠性高、覆盖地区广和定位精度高等优势。 相似文献
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Services of general interest fulfill people's daily needs and are important for their well-being. In Germany, interacting socioeconomic and demographic processes currently lead to a spatial concentration of such services. Rural areas are particularly affected, resulting in a deterioration of living conditions. Nevertheless, although in the media and in policy these processes are intensely discussed against the background of the German political and scientific discourse on ‘Daseinsvorsorge’, little is known about their dimensions. However, such knowledge is important for both policy and scientific policy advice, as ‘Daseinsvorsorge’ is a key concept in German spatial planning discourse, rooted in the normative political goal of guaranteeing comparable living conditions throughout Germany. This goal includes the aim of ensuring a sufficient offering of services indispensable for life throughout the country. One subject area where a spatial concentration can be observed is retail food sales. As a consequence, especially in rural areas, the network of food shopping locations becomes more wide meshed. Against this background, the German petrol-sector claims that in rural regions, petrol station shops (PSS) might replace a missing local food retailer. Based on the data from an accessibility analysis of petrol stations, supermarkets and discounters, together with considerations on the assortment of PSS, the article analyses the potential of such shops to fulfill this function in rural Germany through the lens of ‘Daseinsvorsorge’. The analysis reveals the following: (1) PSS still mainly serve impulse shopping needs, offering only a very limited assortment of staple foods; (2) in the majority of regions with no supermarket or discounter accessible by foot, PSS are also not accessible by foot; and (3) by car, the picture is very similar. Considering these points, it can be concluded that in Germany, PSS cannot at this time fully replace a missing local retail trade, especially in rural areas. 相似文献