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91.
Eva M. Valero Juan L. Nieves Sérgio M. C. Nascimento Kinjiro Amano David H. Foster 《Color research and application》2007,32(5):352-360
Many spectral‐recovery methods using RGB digital cameras assume the underlying smoothness of illuminant and reflectance spectra, and apply low‐dimensional linear models. The aim of the present work was to test whether a direct‐mapping method could be used instead of a linear‐models approach to recover spectral radiances and reflectances from natural scenes with an RGB digital camera and colored filters. In computer simulations, a conventional RGB digital camera with up to three colored filters was used to image scenes drawn from a hyperspectral image database. Three measures were used to evaluate recovery with the direct‐mapping method: goodness‐of‐fit, root‐mean‐square error, and a color‐difference metric. It was found that with two and three filters both spectral radiances and reflectances could be recovered sufficiently accurately for many practical applications. With little increase in computational complexity, an RGB camera and a few colored filters can provide significantly better recovery of natural scenes than an RGB camera alone. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 352–360, 2007 相似文献
92.
陈新瑜 《电网与水力发电进展》2003,19(3):39-41
在统计分析的基础上,归纳总结了陕西南部各类路基病害的分布特征,并从自然因素和人为因素两个方面分析了各类路基病害发生的主要控制因素。 相似文献
93.
大豆蛋白纤维的性能及产品开发 总被引:11,自引:4,他引:7
主要描述了大豆蛋白纤维的性能,介绍了大豆蛋白纤维的生产以及大豆蛋白纺织新产品的开发。 相似文献
94.
ABSTRACT: A new natural apple polyphenol oxidase (PPO) inhibitor(s) from housefly ( Musca domestica L.) was discovered. Crude inhibitor (s) isolated by buffer extraction, heat treatment, and dialysis from housefly pupae inhibited the activity of apple PPO up to 90% at pH values above 5.0. Inhibition was strictly pH-dependent. The inhibitor(s) was further characterized by employing heat, freezing and thawing, irradiation, pH adjustment, and ultrafiltration studies. The potential PPO inhibitor(s) was stable to heating at 100 °C for 1 h, repeated freezing and thawing, and irradiation. The inhibitor(s) was most stable at pH around 5.0 and least stable at alkaline pH. The PPO inhibition profile of housefly during metamorphosis also was evaluated. 相似文献
95.
Yukio Sato Tomohito Tanaka Fumiyasu Oba Takahisa Yamamoto Yuichi Ikuhara Taketo Sakuma 《Science and Technology of Advanced Materials》2003,4(6):137
SrTiO3 and ZnO bicrystals with various types of boundaries were fabricated in order to examine their current–voltage characteristics across single grain boundaries. Their grain boundary structures were also investigated by high-resolution transmission electron microscopy. In Nb-doped SrTiO3, electron transport behaviors depend on the type of boundaries. Random type boundaries exhibit highly non-linear current–voltage characteristics, while low angle boundaries show a slight non-linearity. On the contrary, undoped ZnO does not exhibit non-linear current–voltage characteristics in any type of boundaries including random ones. It is suggested that the differences observed in current–voltage properties between the two systems are mainly due to the difference in the accumulation behavior of acceptor-like native defects at grain boundaries. A clear non-linearity is obtained by means of Co-doping even for the highly coherent Σ1 boundary in a ZnO bicrystal. This is considered to result from the production of acceptor-like native defects by Co-doping. 相似文献
96.
介绍了集团变分法的集团概率变量、配置熵等统计分析的理论基础及Helmholtz自由能的描述模型.提出了巨势及相对化学势的几何分析理论.讨论了应用集团变分法和巨势分析理论进行相平衡计算的过程,并分析了同结构平衡相图计算的若干实例. 相似文献
97.
98.
介绍了深圳市机动车发展现状,分别用趋势外推法、城市比较分析法和分类法预测了2010-2020年深圳市的机动车保有量,最后预测了机动车的油气需求量。 相似文献
99.
湿法生产线的技术更新改造有异地新建新型干法生产线和原地改成湿磨干法生产线二种。浙江虎山集团(?)3.0 m×88.68 m湿法线的改造,经方案比较和生产原料的状况,采用了湿磨干烧方案。其中,料浆脱水采用了真空吸滤法,浇成系统采用了南京院专有技术。改造投产后,获得了优质、高产、低耗和安全生产的技改效果。 相似文献
100.