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51.
TVGA图形适配器对多卜勒风速的显示 总被引:2,自引:0,他引:2
着重介绍单多卜勒雷达圆锥体扫描获得的风速,回波强度资料在显示之前的数据处理方法,以及用TVGA图形适配器的高分辨显示模式(800×600,256色)显示多卜勒风场的技术。 相似文献
52.
The impact of the warm SST bias in the Southeast Pacific (SEP) on the quality of seasonal and interannual variability and ENSO prediction in a coupled GCM is investigated. The reduction of this bias is achieved by means of empirical heat flux correction that is constant in time. It leads to a wide range of changes in the tropical Pacific climate including enhanced southeast trades, well-defined dry zone in the SEP, better simulation of the South Pacific Convergence Zone and stronger cross-equatorial asymmetry of the mean state in the eastern Pacific. As a result of the mean climate correction, significant improvements in the simulation of the seasonal cycle of the oceanic and atmospheric states are also observed both at the equator and basin-wide. Due to more realistic simulation of the seasonal evolution of the cold tongue, tropical convection and surface winds in the corrected version of the model, phase-lock of ENSO to the annual cycle looses its strong semi-annual component and becomes quite similar to the observed, although the amplitude of ENSO is reduced. Zonal wind stress response to the SST anomalies in the central-eastern Pacific also becomes more realistic. ENSO retrospective forecast experiments conducted with the directly coupled and the flux-corrected versions of the model demonstrate that deficiencies in the seasonal evolution of the cold tongue/Inter-Tropical Convergence Zone complex (that were largely due to the SEP bias in this model) and the related errors in the ENSO phase-lock to the annual cycle can seriously degrade ENSO prediction. By reducing these errors, ENSO predictive skill in the coupled model was substantially enhanced. 相似文献
53.
Due to the bird's eye view of remote sensing sensors, the orientational information of an object is a key factor that has to be considered in object detection. ... 相似文献
54.
中国西部地区典型岩质滑坡机理研究 总被引:9,自引:0,他引:9
本文根据作者在中国西部地区多年的研究工作实践,对几类典型的大型岩质斜坡变形及失稳机理进行了较为深入的分析,重点阐述了这些大型滑坡形成的地质条件、斜坡变形过程及发生机理的"概念模型",其中包括滑移-拉裂-剪断的三段式模式、挡墙溃决模式、"超级强夯"模式等.这些机理及模式的提出,对这一地区的防灾减灾实践具有一定的指导意义. 相似文献
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Wen-Chao Huang Hong-Wen Yu 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2016,10(4):269-279
In this study, the failure mechanisms for Chiuliao 1st Levee and Gueishan Levee in Taiwan were re-examined comprehensively considering the uncertainty of different parameters. Results have shown that for Chiuliao 1st Levee, the slope sliding failure has a higher coefficient of variation (COV). For Gueishan Levee, retaining wall sliding and overturning failure have higher values of COV instead. It can also be found that the scouring depths affect the stability of the levee significantly, therefore, a protecting system for the backfill material may be necessary to increase the stability of the levee effectively. 相似文献
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Cheng Yinhe Zhou Shengqi Wang Dongxiao Lu Yuanzheng Huang Ke Yao Jinglong You Xiaobao 《中国海洋湖沼学报》2016,34(3):619-628
The observed characteristics of lower atmospheric ducts over the South China Sea(SCS) were analyzed based on Global Position Systerm(GPS) radiosonde data collected four times daily during autumn open cruises from 2006 to 2012.Duct occurrence,thickness,and strength over the SCS were about 40%,150-m thick,and 8 M units,respectively,which were larger than during the summer monsoon period.Most ducts occurred at heights 1 500 m and these ducts easily trap electromagnetic wave clusters with wavelengths 2 m.Diurnal variation of the SCS ducts appeared evident.They occurred more often at midnight at higher altitudes(about 1 100 m),with a thickest layer of about 145 m and less frequently during the evening at lower altitudes(about 800 m),with a thinnest layer of about 125 m.Moreover,ducts during the daytime at a mean height of about 900 m,with the greatest strength of about 10 M units.Furthermore,all duct variables observed over the SCS in autumn decreased from north to south.These findings are useful not only in the design of radar and communication systems,but also for evaluating possible effects of anomalous propagation on meteorological radar and military applications. 相似文献
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