共查询到20条相似文献，搜索用时 78 毫秒
1.
近年来,随着空间信息获取技术的发展,激光扫描技术在城市三维数据采集中应用越来越广泛,本文以车载激光扫描点云数据为研究对象,利用点云数据空间分布特征和反射强度信息,结合道路标线的几何特征,提出一种快速有效地从离散点云中提取道路标识线的方法。该方法首先利用车载激光点云数据中的高程信息和反射强度信息对原始点云进行滤波。然后将分割后的点云数据投影到二维平面中,利用反射强度信息和点云空间分布信息生成点云强度特征图像,利用标线规则的几何形状,对连通区域进行道路标识线的提取。最后,基于道路标识线的语义信息,利用Hough变换对检测到的标识线进行分类和连接,从而提取完整、准确的三维道路标识线点云数据。通过居民区和高速公路扫描数据处理案例,实现了高速公路虚实标识线和干扰因素较多的居民区界线的自动提取,验证了上述道路标识线提取方法的可靠性,应用效果较好。 相似文献
2.
3.
针对城市典型道路结构特征，提出一种车载道路面点云数据提取方法。根据高程阈值算法对原始车载激光扫描点云数据进行滤波处理，得到地面点，再使用改进区域生长算法对地面点进行处理，提取得到道路面点云。通过实测车载激光扫描数据进行实验，结果表明，本文提出方法提取道路面点云结果的检测质量q、完整性r以及准确性p均在93%以上，本文方法是行之有效的。 相似文献
4.
本文针对以往道路边界信息获取存在的效率差、精度低等问题,提出一种基于移动车载激光扫描点云数据的道路边界点提取方法。首先,为减少道路原始点云数据量,提高后续处理算法的效率,使用Volex Grid滤波器下采样原始车载点云数据,得到抽稀后道路点云数据;其次,使用直通滤波算法对抽稀后点云数据进行滤波处理,剔除高大建筑物、植被等点云数据并使用梯度滤波算法分离地面点与非地面点;最后,使用边界特征估计法完成道路三维边界点的提取。使用两组不同类型路段点云数据进行实验,结果显示本文方法提取直线路段道路边线的完整率与准确率为96.3%、98.8%,提取弯曲路段道路边线的完整率与准确率为91.8%、96.7%,表明本文方法能够有效提取道路边界点,具有较高的准确性,能够为高精地图制作提供可靠的数据支撑。 相似文献
5.
6.
7.
8.
针对道路车载激光扫描点云数据中行道树与其他地物相互遮掩,存在杆状物分类困难的情况,本文提出了一种基于车载激光扫描数据的行道树自动提取方法。首先,构建格网并地形点云滤波,提取非地面点,从而提升后续算法的运算效率;其次,在非地面点的基础上构建空间体元进行邻域分析,提取树干点云,同时建立树冠分层点云投影面积理论,提取得到树冠点云;最后,使用改进分割算法进一步修正树冠点云归属,实现行道树的单体化。使用两组不同类型道路点云数据进行实验,结果显示本文算法提取行道树的平均提取完整率与正确提取率分别为90.73%、91.22%,较对比方法具有一定优势,为行道树的高效、快速、准确提取提供了新的思路。 相似文献
9.
提出了一种从车载激光扫描数据中自动提取路面的方法。通过分析车载激光扫描点云的空间特征,提出运用近似平面约束法、有序最小二乘坡度估计法和多尺度窗口迭代分析法进行初始路面种子点提取;然后基于局部坡度滤波方法提取所有的路面点;最后选择两组实际点云数据进行实验。结果表明,该方法能快速准确地提取高速公路路面点云,实验数据的提取准确率为95.74%,完整率为98.11%。 相似文献
10.
车载点云数据的自动分类与提取是进行城市三维建模的基础和关键步骤。文章利用国产SSW车载激光建模测量系统获取的点云数据丰富的底层信息(点云基于激光扫描坐标系的坐标、相邻点梯度等)提出了一种针对道路边线的自动分类与提取算法。通过粗提取和精提取两个步骤得到准确的道路边线点云,再采用最小二乘拟合算法进行拟合,自动生成道路边线矢量文件。 相似文献
11.
采用Landsat TM数据分析了阿克苏河—塔里木河断面水质污染状况,通过波段的DN值和常规监测数据建立能反映水质状况的
污染物监测模型。结果发现,将2000年常规监测数据代入模型后,与遥感数据的结果基本吻合| 重建阿克苏河—塔里木河的连续水体
污染变化曲线,得出污染物浓度随着远离上游而增加。 相似文献
12.
13.
Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data 总被引：5，自引：0，他引：5
C. Bhuiyan R.P. Singh F.N. Kogan 《International Journal of Applied Earth Observation and Geoinformation》2006,8(4):289-302
The hard-rock hilly Aravalli terrain of Rajasthan province of India suffers with frequent drought due to poor and delayed monsoon, abnormally high summer-temperature and insufficient water resources. In the present study, detailed analysis of meteorological and hydrological data of the Aravalli region has been carried out for the years 1984–2003. Standardised Precipitation Index (SPI) has been used to quantify the precipitation deficit. Standardised Water-Level Index (SWI) has been developed to assess ground-water recharge-deficit. Vegetative drought indices like Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) and Vegetation Health Index (VHI) have been computed using NDVI values obtained from Global Vegetation Index (GVI) and thermal channel data of NOAA AVHRR satellite. Detailed analyses of spatial and temporal drought dynamics during monsoon and non-monsoon seasons have been carried out through drought index maps generated in Geographic Information Systems (GIS) environment. Analysis and interpretation of these maps reveal that negative SPI anomalies not always correspond to drought. In the Aravalli region, aquifer-stress shifts its position time to time, and in certain pockets it is more frequent. In comparison to hydrological stress, vegetative stress in the Aravalli region is found to be slower to begin but quicker to withdraw. 相似文献
14.
15.
Piyoosh Rautela Ramesh Chandra Lakhera 《International Journal of Applied Earth Observation and Geoinformation》2000,2(3-4)
The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies. 相似文献
16.
ZHAN F. Benjamin 《地球空间信息科学学报》2011,(1)
Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2000, 200... 相似文献
17.
GNSS系统及其技术的发展研究 总被引：3，自引：1，他引：2
阐述了国际上卫星导航系统的总体发展,对美、俄、欧、中的四大全球系统,以及相关的区域系统和增强系统进行了简单的介绍,研究分析了GNSS系统及其技术的发展趋势,同时分析了我国Compass全球系统面临的机遇和挑战,并提出了我国未来工作的建议. 相似文献
18.
“4D”技术及其应用 总被引：13，自引：0，他引：13
介绍“４Ｄ”（即数字地面模型、数字正射影像、数字栅格地图和数字线划地图）系列产品的生产流程、关键技术、及其在耕地保护、防灾减灾救灾和城市规划等方面的应用方法。 相似文献
19.
《International Journal of Digital Earth》2013,6(1):66-87
Abstract Virtual Australia is not a well-defined or agreed concept. This discussion paper conceptualises Virtual Australia as a ‘virtual [digital] model containing and representing all non-trivial objects and their contextual environment – from blue sky to bedrock – in real world Australia’. It describes a scenario for Virtual Australia, one or two decades from now, in which the locations and conditions of non-trivial objects and their environment are updated automatically through a combination of remote sensing and wireless communication technologies in support of a ‘Supranet’. It then examines the concept of the ‘Supranet’ – a pervasive information network based largely on wireless technology linking the physical world to a virtual model in real time – and develops and discusses three principal characteristics of the Supranet: the ability to have or collect specific information (know); the ability to process information (think); and the ability to communicate that information. If, in the near future, any or all non-trivial devices are to some extent able to know, think and communicate, the potential for object autonomy will be realised. 相似文献
20.
自动车辆定位导航系统中传感器的误差分析 总被引：1，自引：0，他引：1
对国界定位导航系统中几种常见的辅助传感器所产生的误差进行了分析，导出了不同传感器的误差模型。这些误差模型是估计车辆位置的扩展卡尔曼滤波器的基础，同时也为选择适当的传感器提供了理论根据。 相似文献