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41.
42.
基于小波多分辨率分析的指横纹定位新算法 总被引:2,自引:0,他引:2
针对指横纹感兴趣区域(ROI)难以准确定位的问题,在明确提出指横纹ROI定义的前提下,提出利用小波多分辨率分析进行指横纹ROI自动检测定位的新算法.该方法利用纹理相似性原理,在高频子图采用基于特征向量和区域生长法产生指横纹的候选子区域集合,然后利用低频子图Radon投影得到的指横纹的区域特征对候选子区域进行验证,最后结合直线拟合手指轮廓得到指横纹在原图的有效位置,最终实现指横纹ROI的精准定位.实验证明该算法不仅能有效克服噪声以及手形姿态变化的影响,并且对多种情况有很强的鲁棒性. 相似文献
43.
Multimedia Tools and Applications - Recently, with the widespread popularity of SNS (Social Network Service), such as Twitter, Facebook, people are increasingly accustomed to sharing feeling,... 相似文献
44.
The technique of online/offline is regarded as a promising approach to speed up the computation of encryption, because the most part of computation, such as pairing over points on elliptic curve and exponentiation in groups, can be pre-computed in the offline phase without knowing the message to be encrypted and/or recipient’s identity. The online phase only requires light computation, such as modular multiplication. In this paper, we propose two novel identity-based online/offline schemes: a full secure identity-based online/offline encryption scheme and an identity-based online/offline signcryption scheme. Compared to the other schemes in the literature, our schemes achieve the shortest ciphertext size in both offline and online phases and demonstrate the best performance in offline computation. Our schemes are applicable to devices with limited computation power. They are proven secure in the random oracle model. 相似文献
45.
The impact of delay defects on these functionally untestable paths on overall circuit performance involves identification of such paths determining the achievable path delay fault coverage and reducing the subsequent test generation effort. The experimental results for two microprocessors (Parwan and DLX) indicate that a significant percentage of structurally testable paths are functionally untestable 相似文献
46.
Cheng-Hsing Hsu Po-Chuang Chen Kuang-Yuan Kung Chuan Lai 《The International Journal of Advanced Manufacturing Technology》2007,31(7-8):673-681
The flow field of a long bubble steadily expelling a viscous fluid confined by two closely located parallel plates is examined.
In order to investigate the influence of bubble size on the flow field, a theoretical bubble profile is used to replace the
complicated procedure for computing simultaneously the interface between the gas surface and fluid flows. The present study
showed the two typical flow patterns and also a third flow pattern of the stagnation point moving in the region of the bubble
tip front during transformation of the two typical flow patterns. The vorticity patterns are also drawn for various bubble
profiles and are examined for their effect on the flow. The velocity field is also presented from two different viewpoints
and the phenomena is examined. The stagnation point located on the center line between the bubble tip to the upstream is only
found in the small range of in a channel, where λ is ratio of the bubble width to the distance between two parallel plates. 相似文献
47.
48.
本文介绍一种简单廉价的单片机AT89C2051实现正弦波脉宽调制、保护的逆变器电路,以及逆变器的整体设计和工作原理,为小型正弦波逆变器的设计制作提供了一种较新的思路。 相似文献
49.
Lai Huasheng Chen Baojiu Wang Linsheng Xu Wu Wang Xiaojun Xie Yihua Ren Xinguang Di Weihua 《中国稀土学报(英文版)》2005,23(6)
White body-color (Y, Gd)BxV1- xO4-x :Eu3 phosphors were prepared by coprecipitation reaction. Under VUV excitation at 147 nm, the red emission colorimetric purity of (Y, Gd)BxV1- xO4-x :Eu3 phosphor is much better than that of commercial PDP (plasma display panels) phosphor (Y, Gd)BO3:Eu3 . But its relative emission intensity is only about 90% of the commercial phosphor. 相似文献
50.
本文着重研究了榨菜自动包装机控制系统的可靠性,并对其运行状态进行通讯监测 相似文献