数字东莞三维地质灾害信息发布平台设计与实现     

李国洋  徐启恒 《测绘与空间地理信息》2017,(4)

东莞市三维地质灾害信息发布平台基于stamp GIS三维技术,利用GIS强大的数据管理与分析能力,实现了东莞市地质灾害数据专题数据管理、群测群防、防灾知识宣传、二三维一体化显示及应用,为相关职能部门提供决策依据。  相似文献   

统计地理空间框架建设的国际经验及对中国的启示     

高寒松 《测绘与空间地理信息》2017,40(Z1)

为了更好地整合统计地理空间信息,联合国成立了统计和地理信息整合专家组,目标是推进全球统计地理空间框架的实施.全球统计地理空间框架为各国提供了通用的标准和方法,以促进统计和地理空间信息的整合,并提高了结合空间信息的统计数据的可用性,让统计更好地服务于决策.本文介绍了构成统计地理空间框架五项原则的具体内容和相关国际经验,并分析了国内实施框架的基础条件、有利因素和困难.建议国家统计局在今后的普查和统计调查中,参照全球统计地理空间框架原则,加强统计和地理信息的整合,并提出了具体措施.  相似文献   

一种加快BDS精密单点定位初始化的方法     

杨克凡  柴洪洲  潘宗鹏 《测绘工程》2017,26(6)

由于BDS卫星的星座特性及卫星的轨道和钟差的精度影响,使得传统消电离层组合精密单点定位(PPP)的初始化时间较长。针对上述问题,文中对附加电离层约束的非组合精密单点定位算法进行研究。首先介绍非组合PPP算法,分析其与传统PPP的差异;其次分别利用CODE电离层格网产品,以反距离加权算法计算的站星电离层延迟、低阶球谐函数建立的区域电离层产品等作为先验信息对非组合PPP进行约束。通过MGEX观测网实测数据静态和仿动态计算表明,相比传统消电离层组合PPP,附加电离层约束的非组合PPP能够有效缩短初始化时间,同时能够获得高精度的定位结果。  相似文献   

多卫星系统融合精密单点定位性能分析     

杨松  张显云  杜宁  鲍新雪  刘芳诚 《测绘工程》2017,26(6)

随着全球四大卫星导航系统格局的成型,卫星定位系统已从单系统模式发展为如今多系统、多频率融合定位、交互操作的模式。在分析多系统精密单点定位模型及各误差项处理策略的基础上,利用RTKLIB进行GPS,GLONASS,GALILEO,BDS多系统融合精密单点定位试验,并分析其动/静态定位性能。实验结果表明:在单系统空间几何构型较差的情况下,多系统融合精密单点定位较单GPS定位精度可提高20%~40%,收敛时间可缩短35%~50%;在截止高度角超过40°的情况下,单系统会因可见卫星数量不足而无法完成连续定位,而多系统仍能实现高精度的连续定位。这在城区、山区或卫星遮蔽较严重的不利环境中有重要的利用价值。  相似文献   

“多规合一”信息平台架构设计——以南京市为例   总被引：3，自引：0，他引：3  

孙玉婷  吴掠桅  秦萧 《测绘通报》2017,(12):117-121

"多规合一"是党和国家近年来积极推进的改革措施,是推进城市治理体系和治理能力现代化的有力抓手。"多规合一"信息平台是科学开展"多规合一"工作,促进部门规划数据共享共建、加强各规划编制过程衔接的重要技术支撑。在当今智慧城市建设如火如荼,"天地图""互联网+政务服务"等政府改革措施大力推进的背景下,"多规合一"信息平台应当如何构建,如何有效衔接既有智慧城市成果,是一项需要综合考虑的问题。本文以南京市为例,在深入梳理国内典型城市"多规合一"信息平台建设经验的基础上,从数据架构、业务架构、应用架构、技术架构4个方面全面开展"多规合一"信息平台架构设计,以期为后续其他城市信息平台的建设实施提供指导。  相似文献   

THE ANALYSIS OF MECHANISM OF IMPACT OF AEROSOLS ON EAST ASIAN SUMMER MONSOON INDEX AND ONSET     

沈新勇  黄文彦  陈宏波 《热带气象学报(英文版)》2017,23(4):357-367

RegCM4.3, a high-resolution regional climate model, which includes five kinds of aerosols(dust, sea salt,sulfate, black carbon and organic carbon), is employed to simulate the East Asian summer monsoon(EASM) from 1995 to 2010 and the simulation data are used to study the possible impact of natural and anthropogenic aerosols on EASM.The results show that the regional climate model can well simulate the EASM and the spatial and temporal distribution of aerosols. The EASM index is reduced by about 5% by the natural and anthropogenic aerosols and the monsoon onset time is also delayed by about a pentad except for Southeast China. The aerosols heat the middle atmosphere through absorbing solar radiation and the air column expands in Southeast China and its offshore areas. As a result, the geopotential height decreases and a cyclonic circulation anomaly is generated in the lower atmosphere. Northerly wind located in the west of cyclonic circulation weakens the low-level southerly wind in the EASM region. Negative surface radiative forcing due to aerosols causes downward motion and an indirect meridional circulation is formed with the low-level northerly wind and high-level southerly wind anomaly in the north of 25° N in the monsoon area, which weakens the vertical circulation of EASM. The summer precipitation of the monsoon region is significantly reduced,especially in North and Southwest China where the value of moisture flux divergence increases.  相似文献   

Evaluating the Ability of CRCM5 to Simulate Mixed Precipitation     

É. Bresson  R. Laprise  D. Paquin  J.M. Thériault  R. de Elía 《大气与海洋》2017,55(2):79-93

Precipitation episodes in the form of freezing rain and ice pellets represent natural hazards affecting eastern Canada during the cold season. These types of precipitation mainly occur in the St. Lawrence River valley and the Atlantic provinces of Canada. This study aims to evaluate the ability of the fifth-generation Canadian Regional Climate Model (CRCM5), using a 0.11° horizontal grid mesh, to hindcast mixed precipitation when driven by reanalyses produced by the European Centre for Medium-range Weather Forecasts (ERA-Interim) for a 35-year period. In general, the CRCM5 simulation slightly overestimates the occurrence of freezing rain, but the geographical distribution is well reproduced. The duration of freezing rain events and accompanying surface winds in the Montréal region are reproduced by CRCM5. A case study is performed for an especially catastrophic freezing-rain event in January 1998; the model succeeds in simulating the intensity and duration of the episode, as well as the propitious meteorological environment. Overall, the model is also able to reproduce the climatology and a specific event of freezing rain and ice pellets.  相似文献   

基于动力降尺度的区域集合预报初值扰动构建方法研究   总被引：4，自引：3，他引：1  

张涵斌  李玉焕  范水勇  仲跻芹  卢冰 《气象》2017,43(12):1461-1472

利用全球集合预报系统资料(Global Ensemble Forecast System,GEFS),基于WRF中尺度模式构建了区域集合预报系统,区域集合初值的构建采用两种方案,一种是GEFS全球集合预报初值场直接动力降尺度(称为DOWN集合),另一种是提取GEFS全球集合降尺度后的扰动场,并叠加到区域数值预报系统(北京快速更新循环数值预报系统:Beijing Rapid Update Cycle System,BJ-RUC)分析场上构建集合初值场(称为D-RUC集合)。进行了批量试验,通过对比发现D-RUC集合的中小尺度扰动增长优于DOWN集合,而大尺度扰动分量的增长两者相当,说明与高分辨率分析场叠加可以促进动力降尺度扰动的中小尺度扰动分量的增长。集合预报扰动准确性检验结果显示,短预报时效内DOWN集合扰动明显低估了预报误差,在预报误差较大的位置扰动较小,而D-RUC集合能够更好地识别预报场中哪些位置预报误差较大,而哪些位置预报误差较小。集合预报检验结果表明,D-RUC方法能显著改善短时效预报效果,集合离散度有所增加、均方根误差有所减少,概率预报评分显示D-RUC集合比DOWN集合在短预报时效占优。降水个例分析结果表明D-RUC方法能显著改善短时效内的降水概率预报效果。  相似文献   

New urban map of Eurasia using MODIS and multi-source geospatial data     

Bayan Alsaaideh  Ryutaro Tateishi  Dong Xuan Phong  Nguyen Thanh Hoan  Ahmad Al-Hanbali  Bai Xiulian 《地球空间信息科学学报》2017,20(1):29-38

Urban areas are of paramount significance to both the individuals and communities at local and regional scales. However, the rapid growth of urban areas exerts effects on climate, biodiversity, hydrology, and natural ecosystems worldwide. Therefore, regular and up-to-date information related to urban extent is necessary to monitor the impacts of urban areas at local, regional, and potentially global scales. This study presents a new urban map of Eurasia at 500 m resolution using multi-source geospatial data, including Moderate Resolution Imaging Spectroradiometer (MODIS) data of 2013, population density of 2012, the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP-OLS) nighttime lights of 2012, and constructed Impervious Surface Area (ISA) data of 2010. The Eurasian urban map was created using the threshold method for these data, combined with references of fine resolution Landsat and Google Earth imagery. The resultant map was compared with nine global urban maps and was validated using random sampling method. Results of the accuracy assessment showed high overall accuracy of the new urban map of 94%. This urban map is one product of the 20 land cover classes of the next version of Global Land Cover by National Mapping Organizations.  相似文献   

海潮负荷效应对我国及周边IGS站的影响     

张红强  雷孟飞  王琪洁  彭葳  邵瑞 《测绘科学》2017,42(4)

针对近海区域海潮变化复杂且海潮负荷效应显著,而全球海潮模型在近海区域精度较低的问题,该文提出了将全球海潮模型NAO.99b和区域模型osu.chinasea.2010相结合,分析海潮对中国大陆及周边地区IGS站的影响。使用GAMIT软件解算IGS站实测数据,通过海潮负荷计算软件SPOTL对解算结果进行改正,并对改正效果进行对比和分析。结果表明,海潮负荷对中国及周边区域站点的影响主要体现在垂直方向,对一些站点的影响可以达到厘米级;海潮负荷对站点坐标的改正效果明显,特别是日本的种子岛站改正效果接近30%;站点改正效果从沿海到内陆逐渐减弱。  相似文献