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韩玉英 《成都信息工程学院学报》2002,17(3):188-191
介绍了利用IMB-PC 8088CPU的单板机控制检测多路直流电源过压、欠压。在出现此类故障时能发出报警声,并在显示器上显示故障电源编号,同时切断故障电源,启动同类备用电源,以便维修。 相似文献
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The mobile incoherent Doppler lidar(MIDL),which was jointly developed by State Key Laboratory of Severe Weather(LaSW) of the Chinese Academy of Meteorological Sciences(CAMS) and Ocean University of China,provided meteorological services during the Olympic sailing events in Qingdao in 2008.In this study,two experiments were performed based on these measurements.First,the capabilities of MIDL detection of sea-surface winds were investigated by comparing its radial velocities with those from a sea buoy.MIDL radial velocity was almost consistent with sea-buoy data;both reflected the changes in wind with time.However,the MIDL data was 0.5 m s 1 lower on average than the sea-buoy data due to differences in detection principle,sample volume,sample interval,spatial and temporal resolution.Second,the wind fields during the Olympic sailing events were calculated using a four-dimensional variation data assimilation(4DVAR) algorithm and were evaluated by comparing them with data from a sea buoy.The results show that the calculations made with the 4DVAR wind retrieval method are able to simulate the fine retrieval of sea-surface wind data-the retrieved wind fields were consistent with those of sea-buoy data.Overall,the correlation coefficient of wind direction was 0.93,and the correlation coefficient of wind speed was 0.70.The distribution of retrieval wind fields was consistent with that of MIDL radial velocity;the root-mean-square error between them had an average of only 1.52 m s 1. 相似文献
96.
《New Astronomy》2022
Radio frequency interference (RFI) identification is a key step in radio data processing. In order to efficiently process huge volumes of data produced by modern large radio telescopes, such as the Five-hundred-meter Aperture Spherical radio Telescope (FAST), exceptional balance between accuracy and performance (throughput) is required for RFI flagging algorithms. RFI-Net is a single-process RFI identification package based on deep learning technique, and has achieved a higher flagging accuracy than the classical SumThreshold method. In this paper, we present a scalable RFI flagging toolkit, which can drive parallel workflows on multi-CPU and multi-GPU clusters, with RFI-Net as its core detector. It can automatically schedule the workload and aggregate itself after errors according to the running environment. Moreover, its main components are all pluggable, and can be easily customized according to requirements. The experiments with real data of FAST showed that using eight parallel workflows, the toolkit can process sky survey data at a speed of 66.79 GB/h, which means quasi-real-time RFI flagging can be achieved considering the data rate of FAST extragalactic spectral line observations. 相似文献
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采用不同方法对黄河中游典型风沙滩河流海流兔河19572007年的径流资料进行了分析。采用年内分配不均匀系数法分析表明,海流兔流域径流年内分配均匀,集中度低。应用Mann-Kendall秩次检验法,证明年径流序列存在明显下降趋势。而同时期的降雨量不存在显著的趋势,且降水年内分配十分不均,主要集中在夏季的79月,冬季少雨。利用情势变化指数法(RSI)分析得到海流兔河年径流变化的几个阶段分别为19571967年、19681988年、19892000年、20012007年。通过对比降水资料和径流资料的变化趋势和年内分配,发现降水对径流变化的影响不明显。 相似文献
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介绍了大连九龙地磁监测中心建设过程中场地磁场梯度的跟踪测量情况。根据中国“地震及前兆数字观测技术规范”电磁部分的要求,在地磁台站建筑施工过程中,需要用质子旋进式磁力仪在施工现场对场地磁场背景进行监测。 相似文献
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?????λ??α????????в????????????????????????к????????????????????λ??α????????????????????в????ж???????????????λ??α????????????????????????????????????????????????????????к?????????? 相似文献
100.
在调查华北平原一个污染年限超过35年的石油化工场地时,采用便携式仪器土层测气方法,快速、准确地测定了场地内40多个钻孔不同深度土层中挥发性有机物(VOCs)的浓度。基于对场地地质水文地质条件的认识,以及通过对大量数据的分析对比和应用空间变异分析方法,得出了对场地土层介质中VOCs污染特征的如下认识:(1)土层VOCs浓度的垂向变化可概括为污染源淋滤型、包气带扩散污染型、地下水波动带污染型和混合污染型四种污染类型;(2)在包气带砂土层和粉土层中,VOCs的扩散规律可近似用指数模型描述;(3)包气带土层中VOCs优先积聚在渗透性强的砂性土层中,砂土层中VOCs浓度是粉土层中VOCs浓度的1.5~12倍,平均3.76倍;(4)土层VOCs浓度的水平变异性表现为包气带土层的变异性要比地下水波动带土层大,且水平变异性能在25m尺度内得到充分显示;而土层VOCs浓度的垂向变异性随地而异,变化复杂,很难用统一的一个量化尺度来表征。本文对这一典型污染场地的剖析,有助于从事污染场地调查人员认识我国华北平原石油化工类场地的污染特征,并为调查与治理类似污染场地提供技术依据。 相似文献