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101.
102.
为了强化三维场景内各要素的质量控制,配置和协调好三维场景内各要素之间的相互关系至关重要。在分析基于航空影像的三维场景生产工艺流程的基础上,结合三维场景检查验收中存在的错漏,探讨三维场景质量控制的若干技术问题。 相似文献
103.
针对一景Geoeye-1高分辨率卫星影像,采用RPC模型对其进行正射纠正处理.实验表明,在4角点布设控制点方案下,采用独立的检查点进行检查,纠正精度达0.335m,能够满足国家1∶10000比例尺正射影像的更新要求. 相似文献
104.
105.
Using the radial basis function network model to assess rocky desertification in northwest Guangxi,China 总被引：1，自引：1，他引：0
Mingyang Zhang Kelin Wang Chunhua Zhang Hongsong Chen Huiyu Liu Yuemin Yue Ingrid Luffman Xiangkun Qi 《Environmental Earth Sciences》2011,62(1):69-76
Karst rocky desertification is a progressive process of land degradation in karst regions in which soil is severely, or completely,
eroded. This process may be caused by natural factors, such as geological structure, and population pressure leading to poor
ecosystem health and lagging economic development. Karst rocky desertification is therefore a significant obstacle to sustainable
development in southwest China. We applied a radial basis function network model to assess the risk of karst rocky desertification
in northwest Guangxi, a typical karst region located in southwest China. Factors known to influence karst rocky desertification
were evaluated using remote sensing and geographic information systems techniques to classify the 23 counties in the study
area from low to extreme risk of karst rocky desertification. Counties with extreme or strong karst rocky desertification
risk (43.48%, nearly half of the study area) were clustered in the north, central and southeast portions of the study area.
Counties with low karst rocky desertification (30.43%) were located in the west, northeast and southwest of the study area.
The spatial distribution of karst rocky desertification was moderately correlated to population density. 相似文献
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107.
潼关地区混合岩可划分为四大类及若干亚类,混合岩化的程度与南北向构造挤压力的强弱相关,且随着分布在不同的构造部位而具分带性,混合岩化在宏观上、微观上都表现了多期性;曾称的“花岗伟晶岩”系混合岩作用的产物,应称混合花岗岩。 相似文献
108.
正Objective The renewable capacity is an important attribute of groundwater resources.Most previous studies have focused on the porous aquifer systems by the measurement and analysis of isotopes deuterium(D),oxygen-18(~(18)O),tritium(~3H),and carbon-14(~(14)C)(Chen 相似文献
109.
Drilling engineering is technology-intensive and involves many subjects and large amounts of data. To improve the quality of production and management, decisions need to be made based on the latest data to direct the work on-site. Therefore, it is necessary to establish a safe, reliable, and efficient drilling management system that can meet daily production requirements. In this study, we describe a real-time monitoring system of field data. The system comprises real-time collection of borehole drilling parameters, ground drilling parameters, on-site video and borehole position data, and wireless data transmission to site and rear managers. The system is based on real-time monitoring of field data, the recognition and prediction of the conditions inside the borehole, the wireless transmission of data, and rear-base data analysis and feedback modules. The rear managers can view the real-time and historical drilling data at any time and compare and analyze drilling data by using the rear software of the management system to optimize the drilling program and feedback to the site. The application of the management system in production suggests that it can significantly improve drilling efficiency, reduce drilling costs and accidents in wells, and improve the automation of drilling operations. Moreover, at the same time, it can also predict complex conditions and drilling accidents in time and provide reliable real-time data to drilling technicians for on-site decision making. 相似文献
110.