影像上同物异谱或同谱异物的现象会造成同一混合像元端元在影像上的光谱不唯一。端元差异问题将给端元选择和提取造成困难,并最终影响混合像元分解的精度。为了尽可能减小端元类内差异、扩大类间差异,针对传统算法无法避免端元在不同波...影像上同物异谱或同谱异物的现象会造成同一混合像元端元在影像上的光谱不唯一。端元差异问题将给端元选择和提取造成困难,并最终影响混合像元分解的精度。为了尽可能减小端元类内差异、扩大类间差异,针对传统算法无法避免端元在不同波段的光谱数值尺度相差很大且定权自动化程度低的缺陷,将变异系数概念引入端元差异问题研究中,提出一种适用于多光谱数据的基于加权理论的加权变异系数分析法(Weighted coefficient of variation analysis,WCVA)。分别从理论和实验两方面论证了WCVA的可行性与优越性。在对比实验中,利用同一地区的TM和Geo Eye多光谱影像,从可视化端元空间分布、算法效率和混合像元最终解混精度比较了WCVA和最佳指数因子(Optimal index factor,OIF)结果。实验证明利用本文提出的WCVA方法获得的波段组合具有更高的解混精度(0.183和0.160)。同时运算效率明显高于OIF。因此WCVA不仅能够有效解决端元差异问题,提高混合像元解混的精度,而且具有较高的运算效率。展开更多
This study explores the intricate situation of the coexistence of different identities in Amin Maalouf＇ s Ports of Call （1996）. It contends that identity is complex, flux, and not limited to what is inherited; it i...This study explores the intricate situation of the coexistence of different identities in Amin Maalouf＇ s Ports of Call （1996）. It contends that identity is complex, flux, and not limited to what is inherited; it is rather a psychological, political, and social amalgamation. Thus, each individual has a unique and particular identity, which is completely different from the others＇. This study is a theoretical and analytical survey of Maalouf＇s Ports of Call. It aims at proving that this novel is an example that Maalouf provides to show the challenges that characters of different identities face, and the obstacles that hinder them from assimilation. The argument is mainly based on Edward Said＇s theories that have opened up discussions about Otherness and multiculturalism, alongside with other postcolonial critics, such as Homi Bhabha. Maalouf＇s book In the Name of Identity： Violence and the Need to Belong （1996） is also integral to this study. The study concludes that it might be possible for people, in parallel with the characters of the novel, to challenge the identity predicament that the world is witnessing nowadays, and accept diversities as a way of life, rather than a reason for waging wars.展开更多
文摘影像上同物异谱或同谱异物的现象会造成同一混合像元端元在影像上的光谱不唯一。端元差异问题将给端元选择和提取造成困难,并最终影响混合像元分解的精度。为了尽可能减小端元类内差异、扩大类间差异,针对传统算法无法避免端元在不同波段的光谱数值尺度相差很大且定权自动化程度低的缺陷,将变异系数概念引入端元差异问题研究中,提出一种适用于多光谱数据的基于加权理论的加权变异系数分析法(Weighted coefficient of variation analysis,WCVA)。分别从理论和实验两方面论证了WCVA的可行性与优越性。在对比实验中,利用同一地区的TM和Geo Eye多光谱影像,从可视化端元空间分布、算法效率和混合像元最终解混精度比较了WCVA和最佳指数因子(Optimal index factor,OIF)结果。实验证明利用本文提出的WCVA方法获得的波段组合具有更高的解混精度(0.183和0.160)。同时运算效率明显高于OIF。因此WCVA不仅能够有效解决端元差异问题,提高混合像元解混的精度,而且具有较高的运算效率。
文摘This study explores the intricate situation of the coexistence of different identities in Amin Maalouf＇ s Ports of Call （1996）. It contends that identity is complex, flux, and not limited to what is inherited; it is rather a psychological, political, and social amalgamation. Thus, each individual has a unique and particular identity, which is completely different from the others＇. This study is a theoretical and analytical survey of Maalouf＇s Ports of Call. It aims at proving that this novel is an example that Maalouf provides to show the challenges that characters of different identities face, and the obstacles that hinder them from assimilation. The argument is mainly based on Edward Said＇s theories that have opened up discussions about Otherness and multiculturalism, alongside with other postcolonial critics, such as Homi Bhabha. Maalouf＇s book In the Name of Identity： Violence and the Need to Belong （1996） is also integral to this study. The study concludes that it might be possible for people, in parallel with the characters of the novel, to challenge the identity predicament that the world is witnessing nowadays, and accept diversities as a way of life, rather than a reason for waging wars.
