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41.
42.
曲面刻字的首要问题在于如何选择刀位点,使得文字笔划角度在曲面上与平面时相同。本文的解决方法是将文字图像调和映射到曲面上确定刀位点,由调和映射的保角性质保证角度不变。描述了平面到曲面调和映射的求解过程,并以球面印字为例,进行了数值试验。 相似文献
43.
针对存在部分遮挡的人脸的识别问题,提出了一种改进的基于异值区域消除的人脸识别方法。首先,由训练人脸图像得到平均脸图像,并将测试图像与平均脸图像作差值运算得到误差人脸图像;然后,对误差人脸图像进行分割得到测试人脸图像存在的遮挡区域,并将测试图像和训练图像的相应区域予以去除以形成新的测试图像和训练图像;最后,采用线性回归分类或稀疏编码分类方法实现人脸识别。与同类方法比较,本方法计算相对简单,展现了较好的识别性能提升。基于Yale B和AR标准人脸数据库的仿真测试结果验证了本方法的有效性。 相似文献
44.
三模冗余中局部重构及模块同步技术研究 总被引:1,自引:0,他引:1
传统的三模冗余方法仅能容错,无法进行故障修复,当两个模块出错时系统将无法正常工作;采用局部动态可重构技术虽然可以修复故障,但修复后的模块与其他模块状态不同步,无法立即工作,需等待系统完成当前任务后重新同步,在同步前如果另有模块发生故障,系统仍将无法工作。本文对三模冗余系统中的模块同步方法进行了研究,当某一故障模块被重构修复后,可以迅速与其他模块同步,尽快加入系统工作,避免因故障积累造成的系统失效。该方法可以有效缩短冗余模块从故障修复到重新加入系统工作之间的等待时间,大大提高三模冗余的可靠性。 相似文献
45.
Hamidreza Rashidy Kanan Author Vitae 《Pattern recognition》2008,41(12):3799-3812
Though numerous approaches have been proposed for face recognition, little attention is given to the moment-based face recognition techniques. In this paper we propose a novel face recognition approach based on adaptively weighted patch pseudo Zernike moment array (AWPPZMA) when only one exemplar image per person is available. In this approach, a face image is represented as an array of patch pseudo Zernike moments (PPZM) extracted from a partitioned face image containing moment information of local areas instead of global information of a face. An adaptively weighting scheme is used to assign proper weights to each PPZM to adjust the contribution of each local area of a face in terms of the quantity of identity information that a patch contains and the likelihood of a patch is occluded. An extensive experimental investigation is conducted using AR and Yale face databases covering face recognition under controlled/ideal conditions, different illumination conditions, different facial expressions and partial occlusion. The system performance is compared with the performance of four benchmark approaches. The encouraging experimental results demonstrate that moments can be used for face recognition and patch-based moment array provides a novel way for face representation and recognition in single model databases. 相似文献
46.
In regularized regression the vectors that lie in Krylov and eigen subspaces, formed in PLS and PC regressions respectively, provide useful low dimensional approximations for the LS regression coefficient vector. By preconditioning the LS normal equations we provide a framework in which to combine these methods, and so exploit both of their respective advantages. The link between the proposed method to orthogonal signal correction and to cyclic subspace regression is made. The performance of the proposed solution in reducing the dimension of the regression problem, and the shrinkage properties of the resulting coefficient vector, are both examined. 相似文献
47.
The edge dominating set (EDS) and edge-cover (EC) problems are classical graph covering problems in which one seeks a minimum cost collection of edges which covers the edges or vertices, respectively, of a graph. We consider the generalized partial cover version of these problems, in which failing to cover an edge, in the EDS case, or vertex, in the EC case, induces a penalty. Given a bound on the total amount of penalties that we are permitted to pay, the objective is to find a minimum cost cover with respect to this bound. We give an 8/3-approximation for generalized partial EDS. This result matches the best-known guarantee for the {0,1}-EDS problem, a specialization in which only a specified set of edges need to be covered. Moreover, 8/3 corresponds to the integrality gap of the natural formulation of the {0,1}-EDS problem. Our techniques can also be used to derive an approximation scheme for the generalized partial edge-cover problem, which is -complete even though the uniform penalty version of the partial edge-cover problem is in . 相似文献
48.
We performed an empirical investigation of factors affecting an individual's decision to adopt anti-spyware software. Our results suggested that an individual's attitude, subjective norm, perceived behavioral control, and denial of responsibility significantly affected anti-spyware adoption intention. Also, relative advantage and compatibility showed a significant effect on attitude, visibility, and image on subjective norm, and trialability, self-efficacy, and computing capacity on perceived behavioral control. Interestingly, moral obligation, ease of use, and perceived cost were not as significant as was originally expected. 相似文献
49.
Analysis of Two-Dimensional Non-Rigid Shapes 总被引:1,自引:0,他引:1
Alexander M. Bronstein Michael M. Bronstein Alfred M. Bruckstein Ron Kimmel 《International Journal of Computer Vision》2008,78(1):67-88
Analysis of deformable two-dimensional shapes is an important problem, encountered in numerous pattern recognition, computer
vision and computer graphics applications. In this paper, we address three major problems in the analysis of non-rigid shapes:
similarity, partial similarity, and correspondence. We present an axiomatic construction of similarity criteria for deformation-invariant
shape comparison, based on intrinsic geometric properties of the shapes, and show that such criteria are related to the Gromov-Hausdorff
distance. Next, we extend the problem of similarity computation to shapes which have similar parts but are dissimilar when
considered as a whole, and present a construction of set-valued distances, based on the notion of Pareto optimality. Finally,
we show that the correspondence between non-rigid shapes can be obtained as a byproduct of the non-rigid similarity problem.
As a numerical framework, we use the generalized multidimensional scaling (GMDS) method, which is the numerical core of the
three problems addressed in this paper. 相似文献
50.
在传统的秘密共享方案中,秘密分发者通过秘密通道分发秘密份额给一组参与者.结合Rei方案和Amos方案,提出仅需一个秘密通道的秘密共享方案.在该方案的秘密分发阶段,秘密分发者与参与者之间使用部分广播通道进行通信,秘密分发者与秘密合并者之间使用一个秘密通道进行通信;在秘密重构阶段,参与者与秘密合并者之间使用广播通道进行通信.通过对该方案进行分析可知,该方案的通道数和总的通信量比已知的两个方案具有明显的优势. 相似文献