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111.
Wang Lifang Wu Xiangbin Zhang Baoyi Li Xuefeng Huang Anshuo Meng Fei Dai Pengyao 《Natural Resources Research》2019,28(3):587-607
Natural Resources Research - Quantitative prediction of concealed mineralization is always confronted with difficulties in comprehensive analysis between 2D and 3D data and between qualitative and... 相似文献
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由于传统的二维GIS平台日渐式微,地理信息技术发展的速度越来越快,需要精度更高、表现力更好的三维GIS平台以及相应的解决方案。本文阐述了以Cesium开源前端库为依托,通过倾斜三维模型作为基础数据,实现三维WebGIS平台建设的解决方案,同时通过实例对三维平台的功能进行说明。 相似文献
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由于传统测量手段对于地表沉降监测不足,PS-InSAR技术具有高空间分辨率和一定程度能克服时间、空间以及大气的影响等优势,因而逐渐成为一种大范围地表沉降监测的主要方法。本文利用PS-InSAR技术,通过SARscape软件对收集到的34幅覆盖日本千叶市地区的ENVISAT ASAR遥感影像进行沉降监测实验。实验结果表明:日本千叶市地区最大累计沉降量为58.965 mm,主要集中在城市地区,并且该地区的沉降和地下矿藏开发有关。 相似文献
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Cai Liu Hong-Yan Sun Zhi-Guo Meng Yong-Chun Zheng Yu Lu Zhan-Chuan Cai Jin-Song Ping Alexander Gusev Shuo Hu 《天文和天体物理学研究(英文版)》2019,(5):31-42
The volume FeO and TiO_2 abundances(FTAs) of lunar regolith can be more important for understanding the geological evolution of the Moon compared to the optical and gamma-ray results. In this paper, the volume FTAs are retrieved with microwave sounder(CELMS) data from the Chang'E-2 satellite using the back propagation neural network(BPNN) method. Firstly, a three-layered BPNN network with five-dimensional input is constructed by taking nonlinearity into account. Then, the brightness temperature(TB) and surface slope are set as the inputs and the volume FTAs are set as the outputs of the BPNN network.Thereafter, the BPNN network is trained with the corresponding parameters collected from Apollo, Luna,and Surveyor missions. Finally, the volume FTAs are retrieved with the trained BPNN network using the four-channel TBderived from the CELMS data and the surface slope estimated from Lunar Orbiter Laser Altimeter(LOLA) data. The rationality of the retrieved FTAs is verified by comparing with the Clementine UV-VIS results and Lunar Prospector(LP) GRS results. The retrieved volume FTAs enable us to re-evaluate the geological features of the lunar surface. Several important results are as follows. Firstly, very-low-Ti(<1.5 wt.%) basalts are the most spatially abundant, and the surfaces with TiO_2> 5 wt.% constitute less than 10% of the maria. Also, two linear relationships occur between the FeO abundance(FA) and the TiO_2 abundance before and after the threshold, 16 wt.% for FA. Secondly, a new perspective on mare volcanism is derived with the volume FTAs in several important mare basins, although this conclusion should be verified with more sources of data. Thirdly, FTAs in the lunar regolith change with depth to the uppermost surface,and the change is complex over the lunar surface. Finally, the distribution of volume FTAs hints that the highlands crust is probably homogeneous, at least in terms of the microwave thermophysical parameters. 相似文献
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卫星遥感技术可用于海岛资源调查。Sentinel-2A与Landsat 8两颗卫星都可免费提供空间分辨率较高的多光谱遥感影像,在海岛调查中的应用潜力较大。本文以浙江舟山普陀山岛为例开展了针对这两种影像在海岛植被分类中的应用效果的研究,分别利用Sentinel-2A多光谱成像仪(MSI)和Landsat 8陆地成像仪(OLI)影像基于最大似然法分类获得了该岛阔叶林、针阔混交林、针叶林、灌丛、草丛等植被及其他地物的分布情况,并进行了精度检验,结果表明MSI的总体分类精度略高于OLI。 相似文献
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针对YOLOv3算法对小目标检测较差及出现较多漏检的问题,本文提出了一种优化的YOLOv3算法.首先使用K-means算法计算出与数据集相适用的锚框;其次将扩张卷积引入到YOLOv3网络,用来增强网络高层的感受野,改善小目标的检测效果;然后使用深度可分离卷积取代YOLOv3网络残差模块中的普通卷积,可减少计算量,从而得到一种新型卷积神经网络结构;最后在数据集上进行对比试验.结果表明,优化的YOLOv3算法能够检测出更多目标,降低漏检率,相比于YOLOv3算法,其召回率提高11.86%,F1-score提高2.99%. 相似文献
119.
Sea ice disaster is one of the principal natural hazards that affect some coastal areas of China,and the formation of ice cover in a wave field has important characteristics.However,analysis of the mechanism in which waves affect the thermodynamic process of sea ice is lacking,and the influence of waves is not taken into consideration in numerical models of sea ice,largely because of a lack of simultaneous observations of waves and sea ice.Using observational data of the sea ice cycle in the coastal waters of Liaodong Bay(China),we analyzed the characteristics of hydrology,meteorology,and sea ice thickness during the formation of sea ice,and explored the changes in the interrelationships among heat fluxes,waves,and sea ice under actual sea conditions.The results could provide a decision-making support as a reference to the establishment and improvement of China's early waming system to sea ice disasters,and the protection of ice drilling operations and production platform safety. 相似文献
120.
Analysis on geo-effects of China’s overseas industrial parks: A case study of Cambodia Sihanoukville Special Economic Zone 总被引:1,自引:0,他引:1
China's overseas industrial parks contribute to political and economic cooperation,cultural exchange between home and host countries.Current studies mainly discuss the ef-fect of overseas industrial parks from the perspective of institutional and cultural difference,multi-scale coupling,as well as key partnerships,while little attention has been paid to the comprehensive analysis of overseas industrial parks.Based on a theoretical framework,this paper explores the overall effect of China's overseas industrial parks from the geo-effects perspective by using field interviews and a case study approach.The research shows that:(1)the geo-effects reveal the over effect of overseas industrial parks from the multiple and com-plementary dimensions of geopolitics,geo-economics,geo-society and geo-culture;(2)the Cambodia Sihanoukville Special Economic Zone,as a flagship BRI project,has produced the prominent and positive geo-effects;(3)the institutional-economic-cultural-environmental adaptability of overseas industrial parks is becoming important.Overseas industrial parks must be rooted in the politics,economy,society,and culture of host country;embedded in local social networks;balance the rights and interests of all stakeholders;and form the community of interests,community of destiny,and community of responsibility with political mutual trust,economic integration,cultural inclusiveness,and social harmony.The paper not only deepens the understanding about the overall effect of overseas industrial parks,but also provides decision support and theoretical reference for government policy makers and the overseas investment of enterprises. 相似文献