Measurement of Monochromatic Emissivity of Cement Clinker with Various Fe_2O_3 Content at High Temperature

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基于配准的红外焦平面阵列条纹非均匀性校正

条纹非均匀性是线扫红外焦平面阵列和非制冷凝视型红外焦平面阵列成像系统中一种特殊的固定图案噪声.分析了其产生的原因,提出了一种基于亮度恒定假设和配准的条纹非均匀性校正算法.根据相邻两帧获得亮度均方误差函数,最后通过最小化全局亮度均方误差函数得到全局最优解作为非均匀性校正的参数.实验结果表明,该算法能够在几帧内达到较好的收...     

白云岩型滑石矿的化学提纯及性能表征

本试验以白云石型滑石矿为原料,采用盐酸酸浸法除去其中的碳酸盐矿物,继而采用过筛、连二亚硫酸钠漂白等方法提纯滑石。漂白过程中,试验因素影响最大的是反应时间,其次是搅拌条件、加水量、Na2S2O4加入量。其最佳漂白条件为:Na2S2O4加入量为1%、用水量为原矿的3倍、时间1h,不搅拌。运用差热—热重分析(DTA-TGA)分析得知滑石在1 000℃时发生脱羟反应;X-射线粉末衍射(XRD)分析表明:提纯后白云石及方解石全部除去,只有少许石英残留在滑石中;通过分析其扫描电镜(SEM)分析得知,滑石形貌呈片状,尺寸在5～40μm之间。经测定滑石白度在90%以上,其各项指标均符合橡胶和化妆品优等品标准。     

结合亮度分级和笔画检测的彩色图像文本提取

提出一种彩色图像下的文本提取方法,该方法对彩色图像在R、G、B三个颜色层分别进行亮度分级,以避开传统颜色聚类方法的聚类数目选择问题,降低图像复杂度;考虑到文字笔画的显著方向性特征,并且通常具有稳定的颜色,利用方向梯度算法进行文本粗定位;然后进一步利用多类SVM分类器实现文本区域精确判别。新方法限制了候选区域的种类,从而降低了SVM分类器的训练难度,具有较高的准确性和鲁棒性。     

高耐蚀性和全光亮化学镀Ni-P合金的研究

本文对化学镀Ni-P合金的工艺参数进行研究,确定了最佳工艺条件,采用扫描电镜、电子探针、X射线衍射仪对镀层的成分和组织结构进行分析,得到Ni-P非晶态合金层。试验表明：镀层在15％H2SO4和10％HCI溶液中,具有优良的耐蚀性,其外观有较好的光亮性。     

一种基于线性亮度变化模型的鲁棒的光流算法

提出了一种鲁棒光流算法,用于计算光照强度、帧间运动速度及运动速度变化较大情况下的光流场。在梯度约束方程中嵌入了线性亮度变化模型,以提高大的光照强度变化下算法稳健性;将各向异性扩散方程引入空间方向平滑约束,以改善运动不连续处的流速计算精度,并依此建立了多尺度空间微分光流算法。参数的均衡化得到了线性尺度变化下的恒定能量函数。迭代运算引入运动补偿的概念,使亮度误差减小。实验结果表明,在光照强度和运动速度及速度变化较大时,本文算法具有很好的计算精度,并产生密度100%的光流场。     

彩电基色矩阵电路三基色恢复条件

目前一些文章中对正确恢复三基色需要满足什么条件,以及电路参数的变化对基色恢复的影响等问题分析较少.本文用等效电路法对典型的基色矩阵电路作了一定的理论分析,从此出发讨论了正确恢复出三基色对基色矩阵电路的要求.最后对影响三基色正确恢复的因素也作了一定的分析.结合上述分析得到了最终结论.     

基于余弦相似度的光学伪装效能评估分析

为了解决伪装效能评估手段单一、量化分析手段不足的问题,引入了余弦相似度原理开展模拟评估,对可见光伪装效能评估理论分析进行了优化.基于颜色光学数据特征,利用颜色直方图展现了目标与背景颜色频率分布,研究了样本目标与背景的颜色融合差异性;采用亮度空间分布图展现了亮度空间特征,探索了样本目标与背景的亮度差异性;并对目标和背景图...     

Considering the surround in device-independent color imaging

When viewing images, the relative luminance of the surround has a profound impact on the apparent contrast of the image. For this reason, photographic transparencies intended for projection in a darkened room are produced with an objective contrast substantially higher than that necessary for optimum reproduction as prints viewed in an illuminated surround. the dark surround causes the image elements to appear lighter and this effect is stronger for darker colors resulting in a loss in perceived contrast. This effect is also of great importance in deviceindependent color imaging since resultant images might be observed in a wide variety of media and viewing conditions. Research on psychophysical scaling of brightness and lightness and the effects of background and surround relative luminance on lightness and chroma is reviewed. the importance of this research for device-independent color imaging systems is described along with the prediction of these effects using the RLAB color-appearance model. Finally, experiments testing the use of RLAB and other color-appearance models in cross-media color reproduction applications are described.     

Assessment of the influence of paper formation on the fluorescence contribution to brightness

Paper was produced under controlled conditions with a range of resultant formation and a constant level of fluorescent dye. Brightness and CIE-Whiteness and the fluorescent contribution to brightness or whiteness were measured by directional and diffuse illuminations. Brightness, whiteness, and fluorescence variability were evaluated as the illuminated sample aperture diameter was varied from a maximum of 12.7 mm to a minimum of 6.0 mm over a broad range of paper formation. an increase in the variance of CIE-Whiteness both including and excluding fluorescence is observed as formation degrades. the variance of the fluorescent contribution also increased, but not in a manner to suggest it is independent of the whiteness including or excluding fluorescence measurements. A higher level of instrument noise prevented a similar definitive concl usion for the fluorescent contribution to directional brightness, even though similar trends were observed. an increase in variance was observed for all whiteness and brightness measurements as viewing aperture size diminished. This suggests an opportunity to understand subjective appearance as a function of viewing aperture size. © 1995 John Wiley & Sons, Inc.