基于光谱技术和连续投影算法的润滑油品牌快速鉴别研究

为了实现润滑油品牌的快速无损检测,提出了一种基于可见/近红外光谱透射技术与连续投影算法相结合的润滑油品牌快速鉴别新方法。采用连续投影算法对6种润滑油的可见/近红外光谱数据进行波长变量的筛选,再结合偏最小二乘法建立润滑油品牌的鉴别模型。结果表明,鉴别模型的相关系数r为0.9721,预测均方根误差RMSEP为0.4055,鉴别正确率为91.7%。说明提出的连续投影算法结合偏最小二乘算法具有很好的预测效果。     

一种采用相位测量轮廓术的工件在线三维检测方法

提出了一种基于相移轮廓术在线检测工件三维信息的方法.利用计算机编程产生的一固定正弦光栅图通过数字投影机投射在流水线的一段区域,无需专门的相移装置,当物体在线移动穿过此区域时,使用计量光栅等距离定位发信,控制CCD采集五帧变形条纹图,并采用具有一定特征的标记实现五帧变形条纹图间的亚像素级像素匹配,提取相移变形条纹图,由Stoilov算法计算,得到工件表面截断相位,展开后可得到物体表面三维信息.实验验证了其可行性.     

An algorithmic approach to the construction of homomorphisms induced by maps in homology

This paper is devoted to giving the theoretical background for an algorithm for computing homomorphisms induced by maps in homology. The principal idea is to insert the graph of a given continuous map into a graph of a multi-valued representable map . The multi-valued representable maps have well developed continuity properties and admit a finite coding that permits treating them by combinatorial methods. We provide the construction of the homomorphism induced by such that . The presented construction does not require subsequent barycentric subdivisions and simplicial approximations of . The main motivation for this paper comes from the project of computing the Conley Index for discrete dynamical systems.

     

QF-环上有限生成模嵌入自由模的秩数和最小嵌入的算法

一个模嵌入自由模相当于用坐标来表示元素,这在数学上一直有重要意义．理论上, ＱＦ－环上的模都可以嵌入自由模,但没有好的算法,影响了它的应用．本文给出ＱＦ－环上有限生成模的最小嵌入的一种算法和所嵌入自由模的秩数的估计．     

解线性方程组的一种新方法

本文提出一种求解线性方程组的快速Ｊａｃｏｂｉ迭代方法，该方法在通常的串行计算机上比Ｇａｕｓｓ－Ｓｅｉｄｅｌ方法快，而且精度高，它对收敛慢的大型线性计算特别有效。     

Pure adaptive search for finite global optimization

Pure Adaptive Search is a stochastic algorithm which has been analyzed for continuous global optimization. When a uniform distribution is used in PAS, it has been shown to have complexity which is linear in dimension. We define strong and weak variations of PAS in the setting of finite global optimization and prove analogous results. In particular, for then-dimensional lattice {1,,k} ⁿ , the expected number of iterations to find the global optimum is linear inn. Many discrete combinatorial optimization problems, although having intractably large domains, have quite small ranges. The strong version of PAS for all problems, and the weak version of PAS for a limited class of problems, has complexity the order of the size of the range.The authors would like to thank the Department of Mathematics and Statistics at the University of Canterbury for support of this research.     

一种基于分级分块处理的背景估计算法

视频序列中连续两帧纯背景图像的帧间差服从高斯分布.利用高斯随机变量的峰态和偏态系数的有关性质构造了一种背景子块与目标子块的分块检测算法,并将多分辨率分析的思想引入其中.对帧差图像进行分级分块处理,构造并完善了分级分块背景重建算法,完成了相应的计算机仿真实验.实验结果表明,该算法能快速、有效的获得背景图像.     

一种基于色度学的RGBW信号映射算法评价方法

随着对高亮度、低功耗绿色显示技术的不断追求,RGBW显示技术成为了国内外的热门研究方向,已有多种RGBW显示器在市场上开始推广。由于将传统显示器rgb信号转换到RGBW显示器RGBW信号的映射算法不仅需要保留初始颜色,且需要兼容具有不同子像素布局方式的RGBW显示器,因此,信号映射算法成为RGBW显示的关键。在介绍现有的五种信号映射算法的基础上,分析了RGBW显示器中新增的白色子像素对显示颜色的作用方式以及现有四种RGBW子像素布局方式对映射算法显示效果的影响;提出了优秀映射算法应满足的三点要求,并据此推导出优秀映射算法的普适性等式及衡量映射算法亮度提升能力的亮度因子;针对五种映射算法的模拟实验表明：满足普适性等式的映射算法能更好地保留初始颜色的色调和饱和度,亮度因子可有效表征算法对亮度的提升能力。该模型不仅可用于评价现有映射算法,而且可为新型映射算法的研究提供理论指导,使之兼容于具有不同硬件参数和子像素布局的显示器,有助于RGBW显示技术的普及推广。     

智能算法在晶体色散方程参量反演中的比较研究

为了研究智能优化算法在不同晶体材料色散方程参数反演中的迭代搜索性能问题,根据已测石英和方解石晶体的实验数据,分别采用遗传算法、模拟退火算法和遗传模拟退火算法应用于晶体色散方程的参数反演中,获得了晶体修正的塞耳迈耶尔方程的参量,同时比较了三种算法在迭代搜索性能、算法稳定性、计算时间和差方和等之间的差异,结果表明,三种算法在晶体色散方程参数反演时都可以得到满意的结果,但是,由于遗传模拟退火算法同时具备遗传算法的快速全局搜索性能和模拟退火算法的极强局部搜索性能,使得在晶体色散方程参数反演中的优化效果更优.因此在建立其它材料色散方程时建议采用遗传模拟退火算法,而且这一结果对研究混合智能算法的迭代搜索性能也是有帮助的.     

On the validity of a front-oriented approach to partitioning large sparse graphs with a connectivity constraint

In this paper we consider the problem of partitioning large sparse graphs, such as finite element meshes. The heuristic which is proposed allows to partition into connected and quasi-balanced subgraphs in a reasonable amount of time, while attempting to minimize the number of edge cuts. Here the goal is to build partitions for graphs containing large numbers of nodes and edges, in practice at least 10⁴. Basically, the algorithm relies on the iterative construction of connected subgraphs. This construction is achieved by successively exploring clusters of nodes called fronts. Indeed, a judicious use of fronts ensures the connectivity of the subsets at low cost: it is shown that locally, i.e. for a given subgraph, the complexity of such operations grows at most linearly with the number of edges. Moreover, a few examples are given to illustrate the quality and speed of the heuristic.The work of this author was partially supported by the DGA/DRET under contract 93-1192 and by the Army Research Office under contract DAAL03-91-C-0047 (Univ. Tenn. subcontract ORA4466.04 Amendment 1).The work of this author was partially supported by the National Science Foundation under contract ASC 92-01266, the Army Research Office under contract DAAL03-91C-0047 (Univ. Tenn. subcontract ORA4466.04 Amendment 1), and ONR under contract ONR-N00014-92-J-1890.