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带有差分GPS的多传感器无人直升机航测遥感系统   总被引:1,自引:0,他引:1  
本文主要介绍作者在日本研制的一种基于无人直升机平台的多种传感器航测遥感系统,它直接采用GPS和IMU数据进行地理定位定向而不需要地面控制点。通过实飞数据对系统达到的几何精度进行了验证,结果表明该系统可用来测绘大比例尺地形图以及应用于其他相关领域。  相似文献   
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一、前言人们通过地面陶普生观测网和人造卫星在世界范围内连续对臭氧层进行了长期观测,发现了臭氧层的人为改变这一问题,其变动情况正成为许多研究人员的兴趣中心。作为本文的主题——南极春季臭氧减少的现象(所谓的臭氧洞)是在极地这一观测上易于被人们忽视的地方发现的。极地本来观测站  相似文献   
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基于空间模型的全球粮食安全评价   总被引:3,自引:1,他引:2  
This paper presents a scenario-based assessment of global future food security. To do that,the socio-economic and climate change scenarios were defined for the future and were linked to an integrated modeling framework. The crop yields simulated by the GIS-based Environmental Policy Integrated Climate (EPIC) model and crop areas simulated by the crop choice decision model were combined to calculate the total food production and per capita food availability,which was used to represent the status of food availability and stability. The per capita Gross Domestic Product (GDP) simulated by IFPSIM model was used to reflect the situation of food accessibility and affordability. Based on these two indicators,the future food security status was assessed at a global scale over a period of approximately 20 years,starting from the year 2000. The results show that certain regions such as South Asia and most African countries will likely remain hotspots of food insecurity in the future as both the per capita food availability and the capacity of being able to import food will decrease between 2000 and 2020. Low food production associated with poverty is the determining factor to starvation in these regions,and more efforts are needed to combat hunger in terms of future actions. Other regions such as China,most Eastern European countries and most South American countries where there is an increase in per capita food availability or an increase in the capacity to import food between 2000 and 2020 might be able to improve their food security situation.  相似文献   
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