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野生刺葡萄叶片度量性状研究 被引量:2
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作者 李若兰 熊闻 +3 位作者 鞠延轮 欧阳亚南 谢椰婷 房玉林 《西北林学院学报》 CSCD 北大核心 2017年第1期172-178,217,共8页
以695个野生刺葡萄(Vitis davidii)种质为材料,测量9个叶片度量性状,通过Galet的数值分析法将叶片性状数量化并对野生刺葡萄材料进行分类。结果表明,野生刺葡萄的成熟叶型具有丰富多样性,叶片主脉长为67~272mm,其他叶脉长度和夹角也存... 以695个野生刺葡萄(Vitis davidii)种质为材料,测量9个叶片度量性状,通过Galet的数值分析法将叶片性状数量化并对野生刺葡萄材料进行分类。结果表明,野生刺葡萄的成熟叶型具有丰富多样性,叶片主脉长为67~272mm,其他叶脉长度和夹角也存在不同程度的变异,叶面积变化范围为43.85~573.12cm2。野生刺葡萄叶型变异主成分为叶脉长度和叶面积的变化(占总变异的58.81%),而夹角变化占总变异的15.40%,2个主成分的贡献率累积为74.21%。聚类分析结果显示刺葡萄材料间的欧式平方距离从1到25变化,距离系数为1的材料用A系列表示。在距离系数为5时,刺葡萄材料被分成45类。当距离系数为25时,野生刺葡萄材料被分成2大类,第1类由111个A系列和138个刺葡萄材料组成,而第2大类仅由编号为565和646的2个材料组成。 展开更多
关键词 野生刺葡萄 叶形分析 Galet数值分析
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Fourier-shape-based reconstruction of rock joint profile with realistic unevenness and waviness features 被引量:1
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作者 NIE Zhi-hong WANG Xiang +1 位作者 HUANG Dong-liang ZHAO Lian-heng 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第11期3103-3113,共11页
Rock joint shape characteristics,waviness and unevenness play essential but distinct roles in shear mechanism of rock joints.This study presents a novel method to generate virtual rock joint profiles with realistic wa... Rock joint shape characteristics,waviness and unevenness play essential but distinct roles in shear mechanism of rock joints.This study presents a novel method to generate virtual rock joint profiles with realistic waviness and unevenness features.Firstly,joint profiles are obtained by 3D laser scanning device.Secondly,quantification of waviness and unevenness is conducted by traditional method,including digital filtering technique and roughness parameter RL.Thirdly,the discrete Fourier transform(DFT)method is employed to analyze the joint outlines.Two representative Fourier shape descriptors(D3,D8)for characterization of waviness and unevenness are suggested.Then,the inverse discrete Fourier transform(IDFT)is adopted to reconstruct the joint profiles with random values of phase angles but prescribed amplitudes controlled by D3 and D8.The traditional method is then applied to the reconstructed joint profiles to examine statistically the relationships between D3 and D8 and parameters RL of waviness and unevenness,respectively.The results show that larger D8 tends to result in larger waviness while higher D3 tends to increase unevenness.Reference charts for estimation of waviness and unevenness with different pairs of D3 and D8 are also provided to facilitate implementation of random joint reconstruction. 展开更多
关键词 rock joint profile joint shape analysis discrete Fourier transform joint reconstruction
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