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Accuracy and fastness of iris localization are very important in automatic iris recognition. A new fast iris localization algorithm based on improved generalized symmetry transform (GST) was proposed by utilizing iris symmetry. GST was improved in three aspects: 1 ) A new distance weight function is defined. The new weight function, which is effective in iris localization, utilized the characteristic of irises that the iris is a circular object and it has one inner boundary and one outer boundary. 2) Each calculation of the symmetry measurement of a pair of symmetry points was performed by taking one point of a pair as the starting point of the transformation. This is the most important reason for fast iris localization, due to which, repetitious computation was largely excluded. 3) A new phase weight function was proposed to adjust GST to locate circle target much better because the inner part of iris is darker than the outer part. The edge map of iris image was acquired and GST was only implemented on the edge point, which decreased computation without loss of accuracy. The modification of distance weight function and phase weight function leads to the accuracy of localization, and other ideass peed up the localization. Experiments show that the average speed of new algorithm is about 7.0-8.5 times as high as traditional ones including integro-differential operator and Hough transform method. 相似文献
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为了能够更加准确的了解装载机工作装置的动力学特性,通过刚柔混合建模的方式,对装载机工作装置正载工况下的受力情况进行了计算和研究,并对装载机工作装置仿真模型进行了一个工作循环的动力学仿真,研究了工作装置中动臂的动载荷和相关的节点的状况.分析结果为装载机工作装置的结构优化设计提供了可靠的参考依据. 相似文献
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介绍了利用LabVIEW虚拟仪器技术改造后的傅立叶变换光谱分析实验系统,与采用VB语言开发的实验系统相比具有程序设计工作量小、运行可靠、便于升级、测量精度高的特点,并且可以同时作为展示虚拟仪器技术应用实例的教学平台。 相似文献
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为实现NURBS曲面快速高精度实时差补,提出了基于修正型sigmoid函数的动力学模型,给出了最大速度、弓高误差、加工曲线的曲率半径和插补周期之间的约束条件.该模型在满足jerk、加速度、速度均连续的前提下,将常用的三次多项式S型以及三角多项式S型动力学模型的15个分段数减少至3个.在此基础上,提出采用差商代替导数的优化Adams算法,避免了常用的Taylor展开所遇到的高阶求导计算,求取了差补周期参数.最后通过减少低次零值B样条基函数的计算,对De Boor-Cox递推算法进行了简化设计,提出了精简型De Boor-Cox算法,缩减了计算量.仿真分析表明,所提算法可根据加工路径有效控制进给速度,在保证加工精度的同时,使计算量得到减少,提高了运算速度.实验结果显示本加工方法可以正确计算目标参数,并适合应用于实际加工系统. 相似文献
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VLAN是虚拟局域网(Virtual Local Area Network)的简称,它是在一个物理网络上划分出来的逻辑网络,这个网络对应于OSI模型的第二层网络,它的划分不受网络端口的实际物理位置的限制.分析了创建VLAN的全过程,并给出了详细设置步聚. 相似文献
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介绍了成本意识在当今企业竞争中的重要地位,分析了目前高校教育中教学与市场脱节的现状,论述了加强成本意识对于培养电子信息类人才的实际意义,分析了高校加强成本意识教学的目标,介绍了以电子信息工程专业为代表的工科高等教育中,加强学生成本意识培养的途径,以具体教学环节为例,分析了将成本意识贯穿于实践教学过程中的思路和方法。 相似文献