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基于多特征组的遥感图像中建筑物目标自动识别与标绘的方法 被引量:3
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作者 承德保 《电子与信息学报》 EI CSCD 北大核心 2008年第12期2867-2870,共4页
该文提出了一种新的针对高分辨率遥感图像中建筑物目标自动识别与标绘的方法。该方法首先统计建筑物的多类特征,然后利用PCA方法分析选取最优特征组,将图像分割为建筑物目标区域与非目标区域。最后,提出一种主方向结合面积因子的方法将... 该文提出了一种新的针对高分辨率遥感图像中建筑物目标自动识别与标绘的方法。该方法首先统计建筑物的多类特征,然后利用PCA方法分析选取最优特征组,将图像分割为建筑物目标区域与非目标区域。最后,提出一种主方向结合面积因子的方法将建筑物目标标绘为规则的矢量多边形。实验结果表明,该方法识别率高、准确性好、鲁棒性强,具有一定的实用价值。 展开更多
关键词 目标识别 自动标绘 多特征组 面积因子 主分量分析方法
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Two New Multi-component BKP Hierarchies 被引量:1
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作者 WU Hong-Xia LIU Xiao-Jun ZENG Yun-Bo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第2期193-199,共7页
We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with ... We firstly propose two kinds of new multi-component BKP (mcBKP) hierarchy based on the eigenfunction symmetry reduction and nonstandard reduction, respectively. The first one contains two types of BKP equation with self-consistent sources whose Lax representations are presented. The two mcBKP hierarchies both admit reductions to the k-constrained BKP hierarchy and to integrable (1+1)-dimensional hierarchy with self-consistent sources, which include two types of SK equation with self-consistent sources and of hi-directional SK equations with self-consistent 展开更多
关键词 multi-component BKP hierarchy BKP equation with self-consistent sources κ-constrained BKPhierarchy n-reduction of mcBKP Lax representation
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Leaf stable carbon isotope composition in Picea schrenkiana var. tianschanica in relation to leaf physiological and morphological characteristics along an altitudinal gradient
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作者 ZHANG Hui-wen WU Zhen XIAO Hong-lang 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1217-1228,共12页
To understand the effects of leaf physiological and morphological characteristics on δ13C of alpine trees, we examined leaf δ13C value, LA, SD, LNC, LPC, LKC, Chla+b, LDMC, LMA and Narea in one-year-old needles of P... To understand the effects of leaf physiological and morphological characteristics on δ13C of alpine trees, we examined leaf δ13C value, LA, SD, LNC, LPC, LKC, Chla+b, LDMC, LMA and Narea in one-year-old needles of Picea schrenkiana var. tianschanica at ten points along an altitudinal gradient from 1420 m to 2300 m a.s.l. on the northern slopes of the Tianshan Mountains in northwest China. Our results indicated that all the leaf traits differed significantly among sampling sites along the altitudinal gradient(P<0.001). LA, SD, LPC, LKC increased linearly with increasing elevation, whereas leaf δ13C, LNC, Chla+b, LDMC, LMA and Narea varied non-linearly with changes in altitude. Stepwise multiple regression analyses showed that four controlled physiological and morphological characteristics influenced the variation of δ13C. Among these four controlled factors, LKC was the most profound physiological factor that affected δ13C values, LA was the secondary morphological factor, SD was the third morphological factor, LNC was the last physiological factor. This suggested that leaf δ13C was directly controlled by physiological and morphological adjustments with changing environmental conditions due to the elevation. 展开更多
关键词 Alpine trees Leaf Carbon isotope composition Physiological characteristics Morphological characteristics Altitudinal variation
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