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51.
52.
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
53.
This paper discusses the microstructure of nickel-aluminium bronzes con-taining(9-10)wt% Al and(0.1~5)wt% Ni,in which three eutectoids may exist.Themorphologies of α+γ_2 and α+β'_2 are similar but the latter is finer.In the α+β'_2+γ_2eutectoid structure β'_2 is mainly concentrated at the α/β boundaries,while γ_2 is distrib-uted inside prior B regions.Both K-S and N-W orientation relationships exist betweenα and β'_2(or γ_2)in alloys consisting of α+β'_2 or α+γ_2.However,if the alloy consists ofα+β'_2+γ_2 eutectoid,the lattices of β'_2 and γ_2 are parallel,both of them have the N-Worientation relationship with α. 相似文献
54.
现代汉语中"子"的作用 总被引:1,自引:0,他引:1
“子”在汉语中出现的频率极高,它是一个组词能力非常强的具有语法意义的名词词缀。名词后缀“子”蕴涵着极其丰富的化内容,它不仅有满足结构要求的作用,还有构成语形、区别词义、转换词性和表达情感色彩等作用。 相似文献
55.
This paper outlines the theoretical framework of a two-year two cohort study of inter-related modules to model reading in 300 grades 4, 5 and 6 readers, and describes the specially designed microcomputer programs written in Turbo Pascal to implement this modular approach. In brief, the modular approach postulates the interrelated phonological, morphological modules in processing words and sentence/paragraph processing. These three modules or components are subserved by 10 measurable tasks all implemented on the microcomputer (IBM-PC compatible) with reaction time measures as indices of the different facets of verbal efficiency. Statistical analyses of the large data sets for Phase 1 show the linear structural equation modelling fits the data reasonably well. In particular, the morphology task consistently explains between 32% to 44% of the variance in reading performance in the three grades. The findings lend themselves to specific approaches to habilitation in the different components or sub-components.This study was supported by a grant (No. 410-86-0048) from the Social Sciences and Humanities Research Council of Canada awarded to Che Kan Leong. Simon Lock and Jacky Lau were responsible for the microcompurter programming. Edward Danskin, Melvin Kelley, Donald Simmons, Louise Sellinger, Kristin Strauss and Tara Wiley carried out the experimentation with individual children in the schools. The cooperation of the principals, the teachers and the subjects was greatly appreciated. Requests for reprints should be addressed to Dr. C. K. Leong, Department for the Education of Exceptional children, University of Saskatchewan, Saskatoon, Canada, S7N OWO. 相似文献
56.
李平 《陕西教育学院学报》2003,19(1):87-91
通过解剖镜、扫描电镜和石蜡制片等方法对韭菜花蜜腺的形态结构、位置和发育过程进行了研究。其花蜜腺类型为子房蜜腺中典型的隔膜蜜腺,并属于结构蜜腺,由分泌表皮和产蜜组织构成,不包含维管束。在开花前后,蜜腺组织中的细胞内液泡大小,蛋白质含量都发生了有规律的变化,根据其结构及其变化特点分析了其泌蜜途径。 相似文献
57.
章采用数学形态学运算子对强光束下的水下激光图像进行处理,以去除强光束对目标检测的干扰,在此基础上采用直方图谷低值作为阈值对处理后的图像进行二值化,从而迅速得到目标图像,实现目标检测,实验证明这是一种快速有效的目标检测算法。 相似文献
58.
庐山地质地貌景观类型具多样性特征,大致可分为:气候景观、气象景观、孑遗植物景观、河流景观、湖泊景观、地层景观、构造景观、地貌景观等类型。笔者建议对这些景观采取保护措施。 相似文献
59.
闫顺利 《江苏广播电视大学学报》2006,17(5):20-24
辩证法是人们耳熟能详的范畴,也是常述常新的问题。辩证法的性质即哲学的性质,故对辩证法问题的探讨本质上是一个哲学观问题。当前,关于辩证法是什么以及辩证法同形而上学的关系问题为学界所热衷,但也歧义纷呈。如何划分辩证法的理论形态、坚持对辩证法的科学态度制约着辩证法理论研究的旨归. 相似文献
60.
George W. Hynd Richard M. Marshall Margaret Semrud-Clikeman 《Reading and writing》1991,3(3-4):345-362
Although some form of central nervous system involvement is presumed, evidence establishing a relationship between dyslexia and neurological dysfunction has been correlational. Recently, neuroimaging and postmortem studies have begun to provide direct evidence implicating neuropathological structures in dyslexia. This article reviews computed tomography (CT) and magnetic resonance imaging (MRI) studies examining deviations in brain morphology which appear to be associated with neurolinguistic functioning. Methodological and technical issues are discussed. Based on their own and others research, the authors conclude that dyslexics show variations in specific brain regions, namely, reversed or symmetrical plana temporale (LR), smaller insular length bilaterally, and symmetrical frontal regions. Moreover, recent studies by the senior author and colleagues suggest that specific reading tasks are associated with specific variations in brain morphology. Symmetrical frontal widths was related to poorer passage comprehension, and reversed frontal area symmetry was related to poor word attack skills. Though many conceptual and technical issues remain unresolved, neuroimaging procedures appear to provide direct evidence supporting the importance of deviations in normal patterns of brain morphology in dyslexia. 相似文献