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机载激光雷达(LiDAR)是一种新的获取高精度和高密度地形数据的测量手段,是公路测设中数据采集的理想方式。本文通过对激光雷达获得的散乱点云构建索引,利用坡度变化极值法提取地形特征点,并利用这些特征点生成顾及地形特征的道路纵横断面,可以为道路勘察设计迅速提供高精度的基础资料。 相似文献
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针对台风过后人工巡检电力线路效率低、勘测困难的难题,在收集了台风来临时刻对我国南方架空线路带来的影响资料的基础上,该文总结了台风及暴雨对输电线路运行设备的影响.该文从灾前隐患点排查、灾后灾情勘探和评估等方面着手,研究了基于垂起固定翼无人机载激光雷达的台风灾害后电网巡视的关键技术,并提出了台风前后灾情评估技术路线.通过某电力线路的巡检证明了上述技术路线的可行性.试验表明,基于垂起固定翼无人机载激光雷达技术可以提高面向台风灾害的特殊电力线路巡检的精度、完整性、工作效率. 相似文献
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基于数字图像处理的方法对激光雷达数据进行分析 总被引:1,自引:0,他引:1
激光雷达(Laser scanning,Lidar)是一种新型而高效的获取地形表面信息以及实时获取数字高程模型(DEM)的方法.发展激光雷达技术最初有两个主要目标:一是在森林和沙漠等地区,当人们无法或者很难使用常规摄影测量的方法获取地面信息时,寻找一种有效的替代传统航空摄影方法获取地面信息的手段,于是激光雷达扫描技术应运而生;二是就现代数字化摄影测量与遥感而言,这种数字化和自动化的处理技术可以对大规模的测量数据进行快速处理,同时,这种方法精度更高,费用也更便宜.特别是对实时数字高程模型数据的大规模需求,要求我们不断发展更高效的数据获取手段,来满足用户对数据精度、使用范围、数据获取周期等各方面的要求,激光雷达技术正好满足这些要求. 相似文献
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航空激光雷达是最近十几年开发的最新测量技术.利用激光扫描器所获得的高度数据可以建立精密的地形模型,同时可以获得森林生产力的信息.无论是地形测量还是植被估算,在数据处理时都需要将来自地表和植被的信号分离开,即滤波.数据滤波的方法很多,但是都不成熟,而且处于技术保密状态.本文介绍目前主要的信号分类方法,并开发了动态阈值分离法.该方法以森林为解析对象,通过反复运算逐渐逼近,完成地表和植被的分离,从而实现了地形与森林测量的双重目的.通过引入地形因子把原地形转换为理想平地,大大减少了过度滤波或者滤波不充分的情况.本方法基本实现自动处理,容易操作.利用本方法计算的高度误差(均方差,RMS)为0.4-0.5m.本方法还适用于城市地区高程模型的建立. 相似文献
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针对斜坡地形、台阶地形和植被地貌、分界地貌建立了4种基本模型,研究了不同的地表空间起伏和反射率分布对回波信号时空分布特性的影响,并采用蒙特卡罗方法仿真了4种模型下Geiger探测模式星载激光雷达的高程测量精度,发现:地形起伏主要影响回波信号的时间分布特性,统计条件下可以消除测量误差;回波信号空间分布特性变化主要由地貌(反射率)的变化引起,误差较小可以忽略.研究结果表明:激光三维测绘卫星对垂直陡变地形(如城市建筑)、斜坡地形(如山坡)、分界地貌(如水陆分界)和折射率起伏地貌(如植被地貌等)具有良好的探测能力. 相似文献
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机载激光雷达测量技术是当代航空、航天遥感最具代表性之一的高新测绘技术,它集全球定位、惯性导航、激光测距等高新技术于一体,工作效率、数据精度高,能迅速获取地理空间物体的三维信息数据,一定程度上解决了传统航空、航天摄影测量获取地面三维信息不便的难题,机载激光雷达测量技术实际上已经代表了对地观测领域一个新的技术发展方向。本文重点探讨机载激光雷达点云数据制作DEM的关键生产技术流程,以及在生产过程中的机载激光雷达点云数据常见问题处理方法。 相似文献
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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
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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
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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
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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
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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
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“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
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《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
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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