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排序方式: 共有166条查询结果,搜索用时 31 毫秒
1.
同步定位与建图技术(SLAM)一直是移动机器人领域比较热门的研究方向,它可以给机器人提供强大的环境感知能力;传统的依靠外部位置参考来定位的方法如果无法获得时,移动机器人需要即时定位自身位置来构建增量式地图,因此SLAM技术也就应运而生;对激光SLAM和视觉SLAM的研究现状及最新标志性成果进行了介绍,重点对以相机与激光雷达融合、相机与IMU融合、激光雷达与IMU融合为代表的多传感器融合SLAM技术展开讨论、系统地梳理了几种融合方式的优势与不足,同时介绍了该领域的研究热点语义SLAM,最后讨论了SLAM技术在该领域未来的发展方向以及存在的挑战。 相似文献
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In this study, we investigate the transport of dust particles, its vertical distribution, and the associated meteorological conditions during an Asian dust event that was observed in Seoul, Korea on May 29-31, 2008. This study analyzes data from ground-based and space-borne 2-wavelength polarization lidars, particulate mass concentrations, and synoptic weather data. Surface meteorological station observations of dust phenomena, dust transport model, and weather maps consistently show that the dust particles were transported from the source regions (Inner Mongolia, Man-Ju, and Ordos areas) to Korea via the northeastern part of China. Network observations of the PM10 concentrations in Korea revealed that a majority of the heavy dust particles traveled across South Korea from the northwest to the southeast direction with a horizontal scale of 250-300 km and a traveling speed of approximately 40 km h− 1. This extraordinary dust event, in terms of its intensity and timing during the year, occurred due to the blockage of an unusually intensified low-pressure system in the northeastern part of China as well as high-pressure system centered over the Sea of Okhotsk and the Kuril Islands. The low values of the particle depolarization ratio (δ532) (≤0.05) and color ratio (CR) during the pre-dust period indicate the presence of spherical, non-dust, and relatively small particles. The mean δ532 value was approximately 0.123 ± 0.069 between altitudes of ground ~ 2.8 km, and 0.161 ± 0.049 for near-surface dust layer (ground ~ 1.2 km). This value is quite similar to that obtained during the 3-year SNU-Lidar measurements in Seoul (δ532 ~0.136 ± 0.027). The value of δ532 during the 2nd multilayered dust episode ranged between 0.081 and 0.120 for near-surface dust layers, and between 0.076 and 0.114 for elevated dust layers. The CALIPSO measurements of β532, δ532, and CR also revealed the presence of dense dust aerosols along the transport route. 相似文献
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Mie散射激光雷达研究成都地区大气边界层结构 总被引:3,自引:0,他引:3
基于Mie散射大气激光雷达,对成都地区大气边界层结构随时间变化的特性进行了研究。首先,应用Klett算法对大气激光雷达回波信号进行了反演,得到大气消光系数和后向散射系数。然后,通过对大气后向散射系数曲线进行拟合得到大气边界层混合层高度以及卷夹层厚度等特征参量。基于实测数据对成都地区大气回波信号进行了反演,结果表明,成都地区大气边界层混合层高度较低,卷夹层厚度较薄,且随时间变化的趋势较缓慢,这与成都地区特殊的地理状况有关。 相似文献
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Over the course of the last two years, ScanLAB Projects have explored various fragments of the natural and man-made world through the eyes of their forensic measuring machine. From surface mapping of Arctic ice floes in the Fram Strait (gateway to the Arctic) to the documentation of torture and detention sites in the Balkans, via the accidental editing of a Richard Long sculpture, to purposeful acts of detail theft from Foster and Wren. Here, Matthew Shaw and William Trossell discuss the capture, analysis and refabrication of their digital architectural doppelgängers. 相似文献
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We use airborne lidar data for the summit area of Kilauea Caldera, Hawaii, to explore the utility of topographic data collected by the TOPSAR airborne interferometric radar for volcanology studies. The lidar data are processed to a spatial resolution of 1 m/pixel, compared to TOPSAR with a spatial resolution of 5 m. Over a variety of fresh volcanic surfaces (pahoehoe and aa lava flows, ash falls and fluvial fans), TOPSAR data are shown to have a typical vertical offset compared to the lidar data of no more than ∼2-3 m. Larger differences between the two data sets and TOPSAR data drop-outs are found to be concentrated around steep scarps such as the walls of pit craters and ground cracks associated with the Southwest Rift Zone. A comparison of these two data sets is used to explore the utility of TOPSAR to interpret the topography of volcanic features close to the spatial resolution of TOPSAR, such as spatter ramparts, fractures, a perched lava flow, and eroded ash deposits. Comparison of the TOPSAR elevation and the lidar first-return minus the return from the ground surface (the so-called “bald Earth” data) for vegetated areas reveals TOPSAR penetration into the tree canopy is typically at least 10% and no more than ∼50%, although a wide range of penetration values from 0% to 90% has been identified. Our results are significant because they show that TOPSAR data for volcanoes can reliably be used to measure regional slopes and the thickness of lava flows, and have value for the validation of coarser spatial resolution digital elevation data (such as SRTM) in areas where lidar data have not been collected. 相似文献
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