Content-based shape retrieval techniques can facilitate 3D model resource reuse, 3D model modeling, object recognition, and 3D content classification. Recently more and more researchers have attempted to solve the pro...Content-based shape retrieval techniques can facilitate 3D model resource reuse, 3D model modeling, object recognition, and 3D content classification. Recently more and more researchers have attempted to solve the problems of partial retrieval in the domain of computer graphics, vision, CAD, and multimedia. Unfortunately, in the literature, there is little comprehensive discussion on the state-of-the-art methods of partial shape retrieval. In this article we focus on reviewing the partial shape retrieval methods over the last decade, and help novices to grasp latest developments in this field. We first give the definition of partial retrieval and discuss its desirable capabilities. Secondly, we classify the existing methods on partial shape retrieval into three classes by several criteria, describe the main ideas and techniques for each class, and detailedly compare their advantages and limits. We also present several relevant 3D datasets and corresponding evaluation metrics, which are necessary for evaluating partial retrieval performance. Finally, we discuss possible research directions to address partial shape retrieval.展开更多
While ptychography is an algorithm based on coherent illumination,satisfactory reconstructions can still be generated in most experiments,even though the radiation sources that are used are not ideally coherent.The un...While ptychography is an algorithm based on coherent illumination,satisfactory reconstructions can still be generated in most experiments,even though the radiation sources that are used are not ideally coherent.The underlying physics of this phenomenon is that the diffraction patterns of partially coherent illumination can be treated as those of purely coherent illumination by altering the intensities of the diffracted beams relative to their real values.On the other hand,due to the inconsistency in the altering interference among all the diffraction beams,noise/distortion is always involved in the reconstructed images.Furthermore,for a weak object,the noise/distortion in the reconstruction can be mostly reduced by using a highly curved beam for illumination in the data recording and forcing the dark field diffraction to be zero in the reconstruction.展开更多
提出了一个基于部分计值技术的信息个人化系统PIPEAgent。部分计值理论源于程序转换中如何在给定部分输入的情况下，对程序完成尽可能多的运算从而对程序进行优化这一问题的探讨，PIPEAgent将部分计值理论与信息个人化相结合，以PIPE(Pe...提出了一个基于部分计值技术的信息个人化系统PIPEAgent。部分计值理论源于程序转换中如何在给定部分输入的情况下，对程序完成尽可能多的运算从而对程序进行优化这一问题的探讨，PIPEAgent将部分计值理论与信息个人化相结合，以PIPE(Personalization is Partial Evaluation)理论为基础，结合机器学习技术并采用智能人机交互的Agent构架。该系统已应用于Web信息检索、电子商务应用。展开更多
基金supported by the National Natural Science Foundation of China under Grant Nos. 61003137, 61202185, 61005018,91120005the Fundamental Fund of Research of Northwestern Polytechnical University of China under Grant Nos. JC201202,JC201220,JC20120237+2 种基金the Natural Science Foundation of Shaanxi Province of China under Grant No. 2012JQ8037the Open Fund from the State Key Lab of CAD&CG of Zhejiang University of Chinathe Program for New Century Excellent Talents in University of China under grant No. NCET-10-0079
文摘Content-based shape retrieval techniques can facilitate 3D model resource reuse, 3D model modeling, object recognition, and 3D content classification. Recently more and more researchers have attempted to solve the problems of partial retrieval in the domain of computer graphics, vision, CAD, and multimedia. Unfortunately, in the literature, there is little comprehensive discussion on the state-of-the-art methods of partial shape retrieval. In this article we focus on reviewing the partial shape retrieval methods over the last decade, and help novices to grasp latest developments in this field. We first give the definition of partial retrieval and discuss its desirable capabilities. Secondly, we classify the existing methods on partial shape retrieval into three classes by several criteria, describe the main ideas and techniques for each class, and detailedly compare their advantages and limits. We also present several relevant 3D datasets and corresponding evaluation metrics, which are necessary for evaluating partial retrieval performance. Finally, we discuss possible research directions to address partial shape retrieval.
基金supported by the Funds from the Engineering and Physical Sciences Research Council(Grant No.EP/E034055/1)the One Hundred Talent Project of the Chinese Academy of Sciences and the Financial Support(Grant No.GFZX0205010502.12)
文摘While ptychography is an algorithm based on coherent illumination,satisfactory reconstructions can still be generated in most experiments,even though the radiation sources that are used are not ideally coherent.The underlying physics of this phenomenon is that the diffraction patterns of partially coherent illumination can be treated as those of purely coherent illumination by altering the intensities of the diffracted beams relative to their real values.On the other hand,due to the inconsistency in the altering interference among all the diffraction beams,noise/distortion is always involved in the reconstructed images.Furthermore,for a weak object,the noise/distortion in the reconstruction can be mostly reduced by using a highly curved beam for illumination in the data recording and forcing the dark field diffraction to be zero in the reconstruction.
文摘提出了一个基于部分计值技术的信息个人化系统PIPEAgent。部分计值理论源于程序转换中如何在给定部分输入的情况下，对程序完成尽可能多的运算从而对程序进行优化这一问题的探讨，PIPEAgent将部分计值理论与信息个人化相结合，以PIPE(Personalization is Partial Evaluation)理论为基础，结合机器学习技术并采用智能人机交互的Agent构架。该系统已应用于Web信息检索、电子商务应用。
