不同风区海面雷达后向散射的极化特征对比分析     

董庆  郭华东  王长林 《海洋通报》2000,19(2):1-7

通过对海南省南保港附近海面ＳＩＲ－Ｃ／Ｘ－ＳＡＲ全极化数据的定量研究,对比研究了该海面不同风区海面的全极化信息特征,定量分析了海面散射的极化信息和极化状态的空间结构情况：用散射矩阵的迹解释了不同海区的散射强度对应关系：对比海面散射极化响应可以确定不同成长类型的粗糙海面类型;用极化响应图的对称特点界定“长尺度”和“短尺度”海面;建立全极化海面散射模型。讨论了海面电磁散射的贡献与雷达系统参数之间的定量  相似文献   

Analysis of 1989/1990 main physical fields for air-sea coupled system in the tropical western Pacific     

Yao Huadong  Jiang Dayong  Liu Yimin 《海洋学报(英文版)》1993,12(1):93-105

In this paper, the marine ship observation data sets in the seventh (October 16-December 4. 1989) and eighth (June 1-July 16, 1990) cruises of PRC -US tropical ocean and global atmosphere (TOGA) joint scientific investigation in the tropical western Pacific are used to analyze the elements such as sea surface temperature (SST), surface wind field, fluxes and net heat budget, which are important physical parameters of underlying earth's surface influencing the global mean circulation evolution on seasonal and interannual time scales. These diagnostic analyses are very beneficial to the understanding of the regional climate characteristics and the air-sea interaction mechanism, and the improving of surface flux parameterizations and regional or global climate model.  相似文献   

ARTIFICIAL NEURAL NETWORK CORRECTION OF ROUGH ERRORS OF OBSERVATIONS   总被引：1，自引：0，他引：1       下载免费PDF全文

蒋国荣  张韧  沙文钰  阎俊岳  姚华栋 《Acta Meteorologica Sinica》2002,(1)

In the context of tower measured radiation datasets.following the correction principle meetinga diagnostic equation in data quality control and in terms of a technique for model construction ondata and ANN(artificial neural network)retrieval for BP correction of radiation measurementswith rough errors available,a BP model is presented.Evidence suggests that the developed modelworks well and is superior to a convenient multivariate linear regression model,indicating its wideapplications.  相似文献   

ARTIFICIAL NEURAL NETWORK CORRECTION OF ROUGH ERRORS OF OBSERVATIONS^*          下载免费PDF全文

JIANG Guorong  ZHANG Ren  SHA Wenyu  YAN Junyue  YAO Huadong 《Acta Meteorologica Sinica》2002,16(1):123-132

In the context of tower measured radiation datasets.following the correction principle meeting a diagnostic equation in data quality control and in terms of a technique for model construction on data and ANN (artificial neural network) retrieval for BP correction of radiation measurements with rough errors available,a BP model is presented.Evidence suggests that the developed model works well and is superior to a convenient multivariate linear regression model,indicating its wide applications.  相似文献   

2002年南海季风建立及其雨带变化的天气学研究   总被引：12，自引：1，他引：12  

闫俊岳  唐志毅  姚华栋  张秀芝  柳艳菊  李江龙 《气象学报》2003,61(5):569-579

利用南海海 气通量观测试验资料结合NCEP ,GPCP以及GMS - 5云图资料 ,综合分析了 2 0 0 2年 5～ 6月南海西南季风建立过程及其雨带变化 ,确定 5月 14日西沙及北部海区西南季风爆发 ,5月 15日整个南海季风爆发 ,季风爆发时间属于正常年 ;季风爆发时风向、风速、云量、降水、湿度、辐射及海面温度等要素都发生突变。这种突变是由大气环流的突变造成的。季风爆发前后大气环流变化过程是 :80～ 90°E越赤道气流加强 ,同时印缅低压加深 ,孟加拉湾南北向气压梯度增大 ,而后东亚大陆上气旋发展东移 ,副热带高压东撤 ,孟加拉湾低压槽前的赤道西风突然加强越过中南半岛 ,南海北部首先出现强西南风 ,继而南海季风迅速地全面爆发。孟加拉湾西南风加强到南海季风爆发是一个连续的过程 ,大陆冷空气南下起了重要的作用。南海季风爆发时呈现单雨带型 ,而后由单雨带型转变为双雨带型 ,雨带受副热带高压和季风系统共同影响 ,并且随着副热带高压移动位置变化。  相似文献   

高性能计算技术在气象领域的应用   总被引：3，自引：2，他引：1       下载免费PDF全文

赵立成  沈文海  肖华东  王彬  孙婧  魏敏  李娟  沈瑜 《应用气象学报》2016,27(5):550-558

高性能计算通过应用超级计算机与并行处理技术解决复杂的计算问题,是信息技术发展比较迅猛的领域之一。气象应用始终是高性能计算的重要领域,高性能计算技术有效地解决了高分辨率、高精度气象数值预报模式发展限制,在气象预报预测业务中发挥着核心支撑作用。数十年以来,由于数值天气模式研究和业务运行对计算资源的强烈需求,国内外气象领域高性能计算机及应用迅速发展起来。气象领域对高性能计算能力及系统的可靠性需求日益提升。高性能计算技术将与气象预报应用日益融合,相互影响促进,不断创新发展。为满足气象预报预测业务和科研工作需求,中国气象部门将进一步提升高性能计算能力,并致力于优化集约高性能计算系统布局,高效管理计算资源,发挥最大效益。  相似文献   

一种多系统组合导航快速选星方法     

马宏阳  程鹏飞  李冉  黄华东 《测绘工程》2016,25(1):59-64

采用多卫星导航系统组合导航,定位精度和系统可靠性会大幅提升,但导航定位运算量也会成倍增长。为解决多系统组合导航定位精度与实时性之间的矛盾,提出一种新的选星方法。新方法不追求最小GDOP值,而是以满足导航定位精度的GDOP值为前提,结合模糊理论中隶属函数的思想,按卫星在星座中均匀分布为原则进行选星。推导伪距测量的误差模型,分析了GDOP与测量误差之间的关系。北斗、GPS和GLONASS三系统组合导航选星实验结果表明,在不超过3次求解GDOP值的情况下,新方法能以不小于98%的概率得到GDOP≤4。  相似文献   

Moon-based Earth observation: scientific concept and potential applications   总被引：2，自引：0，他引：2  

Huadong Guo 《International Journal of Digital Earth》2018,11(6):546-557

Although Earth’s surface parameters obtained from satellite data have become more and more precise, it is still difficult to guarantee temporal consistency and spatial continuity for large-scale geoscience phenomena. Developing new Earth observation platforms is a feasible way to improve the consistency and continuity of such data. As the planet’s only natural satellite, the Moon has special advantages as a platform for observing Earth, including long lifetime, whole disk view, tectonic stability and unique perspective. After presenting the observation geometry constructed by using the ephemeris, this paper mainly discusses the characteristics of a lunar platform and the proper Moon-based sensors, as well as the scientific objectives of Moon-based Earth observation. Solid Earth dynamics, the energy budget of Earth, Earth’s environmental elements and the Earth-space environment are four potential applications analysed in this paper.  相似文献   

The Digital Belt and Road program in support of regional sustainability     

Huadong Guo  Yubao Qiu  Massimo Menenti  Fang Chen  Paul F. Uhlir 《International Journal of Digital Earth》2018,11(7):657-669

The Belt and Road initiative has a significant focus on infrastructure, trade, and economic development across a vast region, and it also provides significant opportunities for sustainable development. The combined pressure of climate variability, intensified use of resources, and the fragility of ecosystems make it very challenging, however, to achieve future sustainability. To develop the path in a sustainable way, it is important to have a comprehensive understanding of these issues across nations and evaluate them in a scientific and well-informed approach. In this context, the Digital Belt and Road (DBAR) program was initiated as an international venture to share expertise, knowledge, technologies, and data to demonstrate the role of Earth observation science and technology and big Earth data applications to support large-scale development. In this paper, we identify pressing challenges, present the research priorities and foci of the DBAR program, and propose solutions where big Earth data can make significant contributions. This paper calls for further joint actions and collaboration to build a digital silk road in support of sustainable development at national, regional and global levels.  相似文献   

新疆塔什库尔干县含稀有金属伟晶岩-碳酸岩的时代——对帕米尔构造结稀有金属成矿作用的启示     

王威  马华东  王家鑫  朱炳玉  柳献军 《地质论评》2021,67(4):67041119-67041128

帕米尔构造结位于青藏高原北缘,记录了自新元古代晚期以来到新生代完整的特提斯构造演化过程。在长期的构造—岩浆演化过程中,发育了不同时代、不同类型的成矿事件。野外调查表明,在帕米尔北东段,发育了含绿柱石的伟晶岩及含氟碳铈矿的碳酸岩(碳酸岩—伟晶岩组合)。通过独居石及锆石U-Pb定年,识别出该区两期伟晶岩带(包括碳酸岩),分别是新生代和中生代(19～18 Ma和200 Ma),其中早期含绿柱石伟晶岩形成于古特提斯洋关闭后的伸展阶段,而新生代含氟碳铈矿碳酸岩—伟晶岩组合,与新生代陆内走滑伸展事件相关,表明帕米尔构造结伸展走滑启动的时间可能在19 Ma。结合区域地球化学异常特征,表明在帕米尔地区有望在稀有、轻稀土找矿上获得突破。  相似文献