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91.
Jun Liu Qiong‐Hua Wang Xiao‐Qing Xu Jun Gu 《Journal of the Society for Information Display》2011,19(10):671-674
Abstract— Stereoscopic and autostereoscopic projection‐display systems use projector arrays to present stereoscopic images, and each projector casts one parallax image of a stereoscopic scene. Because of the position shift of the projectors, the parallax images have geometric deformation, which influences the quality of the displayed stereoscopic images. In order to solve this problem, a method based on homography is proposed. The parallax images are pre‐transformed before they are projected, and then the stereoscopic images without geometric distortion can be obtained. An autostereoscopic projection‐display system is developed to present the images with and without calibration. Experimental results show that this method works effectively. 相似文献
92.
协同过滤是推荐系统中应用最为广泛的方法.提出一类基于二部图一维投影与排序相结合的协同过滤算法,文中采用结构相似进行二部图投影并利用随机游走对节点排序.该方法不仅可以防止冷启动,具有较高准确度,且可扩展性良好.另外,该算法可以避免低覆盖率造成的推荐不准确.算法可以有两类不同的实现,分别是基于项协同过滤的项排序算法和基于用户协同过滤的用户排序算法,在标准数据集MovieLens上的测试表明了算法的有效性. 相似文献
93.
94.
A Bayesian approach to variable selection which is based on the expected Kullback-Leibler divergence between the full model and its projection onto a submodel has recently been suggested in the literature. For generalized linear models an extension of this idea is proposed by considering projections onto subspaces defined via some form of L1 constraint on the parameter in the full model. This leads to Bayesian model selection approaches related to the lasso. In the posterior distribution of the projection there is positive probability that some components are exactly zero and the posterior distribution on the model space induced by the projection allows exploration of model uncertainty. Use of the approach in structured variable selection problems such as ANOVA models is also considered, where it is desired to incorporate main effects in the presence of interactions. Projections related to the non-negative garotte are able to respect the hierarchical constraints. A consistency result is given concerning the posterior distribution on the model induced by the projection, showing that for some projections related to the adaptive lasso and non-negative garotte the posterior distribution concentrates on the true model asymptotically. 相似文献
95.
HaengSeok Yang SangKyeong Yun JongHyeong Song SeungDo An HeungWoo Park Shyshkin Ihar Victor Yurlov Lapchuk Anatoly 《Journal of the Society for Information Display》2010,18(6):445-453
Abstract— The development of a compact, efficient VGA projection module to be embedded in mobile devices is reported. The design incorporates laser/laser diode (LD) light sources, Schlieren optics, and a one‐dimensional diffractive spatial optical modulator (SOM). During development, the optical parameters were determined and the relationships between the parameters to optimize the optical specifications were derived. The resulting optimized specifications enable us to manufacture two types of optical modu les as compact as 13 cc and with as little as 10% speckle contrast ratio. 相似文献
96.
Michael J. Hirsch Panos M. Pardalos Mauricio G. C. Resende 《International Transactions in Operational Research》2011,18(4):493-511
The field of computer vision has experienced rapid growth over the past 50 years. Many computer vision problems have been solved using theory and ideas from algebraic projective geometry. In this paper, we look at a previously unsolved problem from object recognition, namely object recognition when the correspondences between the object and image data are not known a priori. We formulate this problem as a mixed‐integer non‐linear optimization problem in terms of the unknown projection relating the object and image, as well as the unknown assignments of object points and lines to those in the image. The global optimum of this problem recovers the relationship between the object points and lines with those in the image. When certain assumptions are enforced on the allowable projections mapping the object into the image, a proof is provided which permits one to solve the optimization problem via a simple decomposition. We illustrate this decomposition approach on some example scenarios. 相似文献
97.
98.
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
99.
100.
区间直觉模糊信息下的双向投影决策模型 总被引:2,自引:0,他引:2
研究权重完全未知、评价信息为区间直觉模糊数的多准则决策问题. 考虑犹豫度影响, 给出备选方案与正理想方案、负理想方案形成的向量表达方式, 提出一种针对区间直觉模糊信息的向量投影测度方法; 构建基于方案投影总偏差最小的非线性规划准则权重确定模型; 给出基于方案投影的相对贴近度测算公式, 并以此对方案进行排序. 最后通过算例对比分析表明了所提出方法的有效性和可行性.
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