基于渐进三角网的机载LiDAR点云数据滤波     

隋立春  张熠斌  张硕  陈卫 《武汉大学学报(信息科学版)》2011,36(10):1159-1163

机载LiDAR点云数据滤波是获取高精度数字高程模型的关键,也是目前LiDAR点云数据处理领域研究的重点和难点之一。提出了基于渐进三角网的机载LiDAR点云数据滤波方法,首先以规则格网和不规则三角网组织数据,采用区域分块法或数学形态学法选取种子地面点建立初始稀疏三角网,通过不断向上加密三角网提取地面点。试验结果表明,该算...  相似文献   

基础地理信息时空数据库管理系统的应用及其测评     

周玉刚  贺智  曲林 《测绘与空间地理信息》2011,34(2):22-25

地理信息具有空间分布特性和时态特性,地理信息数据的快速更新已成为目前研究热点。本文首先通过建立大庆高新技术开发区基础地理信息时空数据库管理系统的应用实例,从数据的收集、组织与处理、数据库建立等过程进行详细的阐述,并实现了数据库的动态关联与更新、时空回溯以及动态可视化等。最后通过对系统功能模块的应用分析,提出对系统软件测试的测评建议。该应用数据库管理系统的建立,为基础地理信息动态数据库的建设提供一个比较完整的解决方案,也为今后的应用推广提供必要的技术支持和基础保障。  相似文献   

基于SuperMap IS.NET的渔港地理信息管理系统设计与实现     

徐硕  刘树  孙璐  王立华 《测绘与空间地理信息》2011,(6):61-63

随着渔港建设规模的不断扩大,渔港基础地理数据和建设信息数据不断增加,建立现代化的渔港地理信息管理系统迫在眉睫。文章介绍了渔港地理信息管理系统的设计与实现。该系统基于WebGIS技术,以SuperMap IS.NET为地图功能开发平台,实现了渔港空间量算、地图浏览、数据查询与管理等功能。  相似文献   

基于ArcGIS的土地用途分区研究     

周峰  杨凤海  邓志  李韵 《测绘与空间地理信息》2011,(6):162-163,171

土地用途分区是土地利用总体规划的重要组成部分,是确定土地用途和采取具体土地利用措施的主要依据之一。GIS的空间分析功能可以辅助土地利用变化分析,完成土地适宜性评价以及土地利用结构和布局调整等规划任务,并根据未来土地用途管制要求,划定和调整土地用途分区。文章以葫芦岛市龙港区土地资源作为研究对象,应用GIS的空间叠置统计分...  相似文献   

区域地磁场的连续傅里叶分析建模方法     

王向磊  苏牡丹  丁硕  申杰敏 《测绘科学技术学报》2011,(6):425-428

研究了利用快速傅里叶(FFT)拟合方法建立连续局部地磁场模型,给出了详细的计算方法.建立的局部地磁场表达式是连续的且形式十分简明,有利于地磁匹配辅助惯性导航的实现.最后,给出了某一地磁异常场的实例,用FFT拟合方法建立了局部地磁异常场模型并与传统的Taylor多项式建模方法进行了比较.仿真结果表明,FFT拟合建模方法精...  相似文献   

Variability of extreme summer precipitation over Circum-Bohai-Sea region during 1961�C2008     

Dejuan Jiang  Kun Wang  Zhi Li  Qiuxian Wang 《Theoretical and Applied Climatology》2011,104(3-4):501-509

The variability of extreme summer precipitation over Circum-Bohai-Sea region during 1961?C2008 was investigated based on the daily precipitation data of 63 meteorological stations using the linear regression method, the non-parametric Mann?CKendall test, and the continuous wavelet transform method. The results showed that there were large spatial differences in the trends of extreme summer precipitation indices. Decreasing trends were found in summer total precipitation, extreme precipitation frequency, intensity and proportion, the maximum consecutive wet days (CWD), and the maximum 1- and 5-day precipitation, and the largest decrease was observed in the central coast area (except CWD), although the trends were not statistically significant at the 5% level at most places. Inversely, the maximum consecutive dry days exhibited non-significant increasing trends. Additionally, the significant 2?C4-year periods were detected for eight indices, showing the significant interannual variability of extreme summer precipitation. Overall, the results of this study indicated that in the last 48?years, there was severe water stress over Circum-Bohai-Sea region, especially in the central coast area, which exerted negative effects on economic development and natural ecosystems.  相似文献   

奎屯垦区1958-2007年气温特征及变化趋势分析   总被引：2，自引：0，他引：2  

姜智  康巍 《沙漠与绿洲气象(新疆气象)》2011,5(1)

利用奎屯垦区1958-2007年气温资料,对奎屯垦区气温特征及变化趋势进行统计分析.分析表明,奎屯垦区的气温日较差月均值在11月和12月最小,4月到9月较大.近50 a年平均气温以0.449℃/10 a的速率升高,并且增暖趋势有变大的特点.奎屯垦区气候变暖对平均最低气温的影响是最大的.奎屯垦区的高温日数以2.00d/10 a的速率增加.而低温日数则以6.815 d/10 a的速率减少.奎屯垦区的初霜日每10 a推迟3.5 d.  相似文献   

Can we improve the spatial predictions of seabed sediments? A case study of spatial interpolation of mud content across the southwest Australian margin     

Jin Li  Andrew D. HeapAnna Potter  Zhi HuangJames J. Daniell 《Continental Shelf Research》2011,31(13):1365-1376

Spatially continuous data of environmental variables is often required for marine conservation and management. However, information for environmental variables is usually collected by point sampling, particularly for the marine region. Thus, methods generating such spatially continuous data by using point samples to estimate values for unknown locations become essential tools. Such methods are, however, often data- or even variable-specific and it is difficult to select an appropriate method for any given dataset. In this study, 14 methods (37 sub-methods) are compared using samples of mud content with five levels of sample density across the southwest Australian margin. Bathymetry, distance-to-coast, slope and geomorphic province were used as secondary variables. Ten-fold cross validation with relative mean absolute error (RMAE) and visual examination were used to assess the performance of these methods. A total of 1850 prediction datasets are produced and used to assess the performance of the methods and the effects of other factors considered. Considering both the accuracy and the visual examination, we found that a combined method (i.e., random forest and ordinary kriging: RKrf) is the most robust method. This method is novel, with a RMAE up to 17% less than that of the control. No threshold in sample density was detected in relation to prediction accuracy. No consistent patterns are observed between the performance of the methods and data variation. The RMAE of three most accurate methods is about 30% lower than that of the best methods in previous publications, highlighting the robustness of the methods selected in this study. The implications and limitations of this study are discussed and a number of suggestions are provided for further studies.  相似文献   

城市地震预警误报的社会影响与措施研究     

徐硕 《地震研究》2011,34(3)

通过对国内外有关地震预警、震时人们心理和行为的文献和试验研究成果的综合分析,结合我国的实际情况,当城市地震预警系统出现误报后,对于社会可能产生的负面影响和潜在的积极影响进行了讨论,并提出相应的措施以减小误报可能产生的负面影响。  相似文献   

地磁DI仪基线值分析处理软件     

郅红魁  何香玲  童正  成娜  刘晓锋 《地震地磁观测与研究》2011,32(4):152-155

现用前兆地磁处理软件的基线值计算功能不完善,导致观测结果滞后,从而制约了台站接收数据的及时性,影响了观测员补测时间的安排.该软件从根本上解决的接收数据的滞后性,能够及时了解观测结果,提高DI仪观测精度,减少观测次数,从而提高观测资料的内在质量.  相似文献