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黑茶山国家级自然保护区样地样线调查方法探讨 被引量:2
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作者 程艳琴 《山西林业》 2022年第S01期38-39,共2页
固定样地和样线监测是自然保护区常用的野生动植物监测手段之一。黑茶山国家级自然保护区通过长期监测,了解和掌握了辖区植被密度、盖度、生物量、种类数量分布以及野生动物状况。
关键词 黑茶山国家级自然保护区 固定地样线调查
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坞岸地样线在船舶落墩中的应用和影响
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作者 谭继良 杨瀛 黎军 《广船科技》 2022年第3期56-58,共3页
通过某散货船落墩后坞墩错位的案例,分析研究了坞岸地样线对船舶落墩的影响,并介绍了工艺改进措施。
关键词 地样线 坞墩 精度
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大型钢结构件组装研配技巧
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作者 付荣柏 《起重机》 2000年第3期16-19,共4页
关键词 大型钢结构件 组装研配 焊接焊缝 地样线
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Smooth cutting pattern generation technique for membrane structures using geodesic line on subplane and spline interpolation 被引量:1
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作者 SHON Su-deok LEE Seung-jae LEE Kang-guk 《Journal of Central South University》 SCIE EI CAS 2013年第11期3131-3141,共11页
Practical techniques for smooth geodesic patterning of membrane structures were investigated.For the geodesic search,adjustment of the subplane of the extracted elements series was proposed,and various spline approxim... Practical techniques for smooth geodesic patterning of membrane structures were investigated.For the geodesic search,adjustment of the subplane of the extracted elements series was proposed,and various spline approximation methods were used to flatten the strip for the generation of a smooth pattern.This search approach is very simple,and the geodesic line could be easily attained by the proposed method without the need for a difficult computation method.Smooth cutting patterning can also be generated by spline approximation without the noise in discrete nodal information.Additionally,the geodesic cutting pattern saved about 21%of the required area for the catenary model due to the reduction of the curvature of the planar pattern seam line. 展开更多
关键词 membrane structures cutting pattern generation geodesic line spline interpolation triangular mesh sub-plane
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Seasonal Effect on Atmospheric Refractivity in Diverse Terrains
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作者 Y.O. Olasoji M.O. Kolawole 《Journal of Environmental Science and Engineering》 2011年第11期1537-1541,共5页
Air masses in the atmosphere have contrasting temperature, humidity and moisture, which influence radio signals traversing the atmosphere. The influence of the atmosphere on refractivity is strongly determined by its ... Air masses in the atmosphere have contrasting temperature, humidity and moisture, which influence radio signals traversing the atmosphere. The influence of the atmosphere on refractivity is strongly determined by its temporal and spatial variability. This paper uses meteorological measurements to investigate the impact of meteorological structures on diverse environments evident in Nigeria. The study hypothesises that refractivity measures could serve as indicators of diurnal radio wave degradation traversing the atmosphere. 展开更多
关键词 RADIOSONDE REFRACTIVITY radio signal hydrostatic component Longley-Rice model
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Multiplicity of closed geodesics on Finsler spheres with irrationally elliptic closed geodesics 被引量:1
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作者 DUAN Hua Gui LIU Hui 《Science China Mathematics》 SCIE CSCD 2016年第3期531-538,共8页
If all prime closed geodesics on(S^n, F) with an irreversible Finsler metric F are irrationally elliptic,there exist either exactly 2 [(n+1)/2] or infinitely many distinct closed geodesics. As an application, we show ... If all prime closed geodesics on(S^n, F) with an irreversible Finsler metric F are irrationally elliptic,there exist either exactly 2 [(n+1)/2] or infinitely many distinct closed geodesics. As an application, we show the existence of three distinct closed geodesics on bumpy Finsler(S^3, F) if any prime closed geodesic has non-zero Morse index. 展开更多
关键词 closed geodesics multiplicity bumpy Finsler spheres irrationally elliptic
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