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161.
多普勒雷达数据处理显示系统 总被引:5,自引:1,他引:5
多普勒天气雷达目前已经成为对短时强烈天气进行监测的主要手段之一。为了方便资料的处理和分析 ,将科研成果向业务应用转化 ,提高观测资料软件和资料处理能力 ,为预报员和科研人员提供方便 ,我们开发了多普勒雷达资料分析显示系统。该软件是兼原始数据处理、反演、显示功能于一体的雷达数据处理系统 ,有很好的兼容性和可移植性 ,其交互式、多线程、多窗口、多任务的汉化操作界面 ,灵活、简便 ,容易使用。根据用户需要 ,水平风场可用风矢量、风羽、流线或等值线等不同方式表达 ,多种水平变量也可以任意叠加 相似文献
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Data Fusion in Distributed Multi-sensor System 总被引:5,自引:0,他引:5
GUOHang YUMin 《地球空间信息科学学报》2004,7(3):214-217
This paper presents a data fusion method in distributed multi-sensor system including GPS and INS sensors“ data processing. First, a residual X^2-test strategy with the corresponding algorithm is designed.Then a coefficient matrices calculation method of the information sharing principle is derived. Finally, the federated Kalman filter is used to combine these independent, parallel, real-time data. A pseudolite (PL) simulation example is given. 相似文献
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流动VLBI天线系统噪声温度及天线效率测量 总被引:1,自引:0,他引:1
我国自行研制的第一套流动VLBI系统——DCW—01型流动VLBI测量仪,目前已在国家重大科学工程“中国地壳运动观测网络”中投入使用。在流动VLBI的观测试验中,天线系统噪声温度和天线效率是观测前系统调试和检测的两项重要内容。天线系统噪声温度是衡量流动VLBI观测系统内部噪声程度的特性指标;天线效率反映了天线系统对到达天线能量的刊用率,在很多计算公式中是一个很重要的参数。因此,精确地测量它们的值是进行相关处理和计算的前提。文中结合我国流动VLBI观测站的研制与建设,介绍了流动VLBI测量仪的天线及接收机系统,并详细阐述了其天线系统噪声温度和天线效率的测量。 相似文献
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W. D. Guo 《国际地质力学数值与分析法杂志》2014,38(18):1969-1989
Recent study indicates that the response of rigid passive piles is dominated by elastic pile–soil interaction and may be estimated using theory for lateral piles. The difference lies in that passive piles normally are associated with a large scatter of the ratio of maximum bending moment over maximum shear force and induce a limiting pressure that is ~1/3 that on laterally loaded piles. This disparity prompts this study. This paper proposes pressure‐based pile–soil models and develops their associated solutions to capture response of rigid piles subjected to soil movement. The impact of soil movement was encapsulated into a power‐law distributed loading over a sliding depth, and load transfer model was adopted to mimic the pile–soil interaction. The solutions are presented in explicit expressions and can be readily obtained. They are capable of capturing responses of model piles in a sliding soil owing to the impact of sliding depth and relative strength between sliding and stable layer on limiting force prior to ultimate state. In comparison with available solutions for ultimate state, this study reveals the 1/3 limiting pressure (of the active piles) on passive piles was induced by elastic interaction. The current models employing distributed pressure for moving soil are more pertinent to passive piles (rather than plastic soil flow). An example calculation against instrumented model piles is provided, which demonstrates the accuracy of the current solutions for design slope stabilising piles. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
170.
Peatland initiation and carbon dynamics in northeast China: links to Holocene climate variability
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Wei Xing Kunshan Bao Wenyong Guo Xianguo Lu Guoping Wang 《Boreas: An International Journal of Quaternary Research》2015,44(3):575-587
Throughout northeast China, the widely distributed peatlands have formed a large carbon (C) pool. However, the relationship between peatland initiation and climate controls is still poorly documented and understood. Understanding the responses of these C‐rich ecosystems to past climate change will provide useful insights into projecting the fate of peatland C in the future. In this study, we present a detailed historical reconstruction of peatland development in northeast China based on 312 basal peat dates, and examine the relationship between Holocene peatland dynamics and climate sensitivity. Our results indicate that peatland initiation started in the early Holocene, and that the majority of peatlands were initiated by and developed during the late Holocene. After the most intensive initiation period of 4.2–0.8 ka, the rate of peatland development slowed, which was concomitant with decreasing insolation and monsoon intensity. The widespread peatland initiation in the late Holocene might have been caused by the cool and moist climate patterns. The optimum timing of the peatland development was not uniform across northeast China, and these spatio‐temporal differences indicate the influences of regional climate and terrain on peatland initiation. Peat‐core data show variations in the long‐term apparent rate of C accumulation (LORCA) during the Holocene, with an average rate of 37.2 g C m?2 a?1. The peak LORCA occurred during 10.5–9.0 ka, probably in response to higher temperatures and stronger East Asia summer monsoon intensities. Both temperature and humidity are important factors influencing the peatland initiation and C dynamics in this region. 相似文献