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A novel texture clustering method based on shift invariant DWT and locality preserving projection
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作者 Rui XING San-yuan ZHANG Le-qing ZHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第2期247-252,共6页
We propose a novel texture clustering method. A classical type of(approximate) shift invariant discrete wavelet transform(DWT),dual tree DWT,is used to decompose texture images. Multiple signatures are generated from ... We propose a novel texture clustering method. A classical type of(approximate) shift invariant discrete wavelet transform(DWT),dual tree DWT,is used to decompose texture images. Multiple signatures are generated from the obtained high-frequency bands. A locality preserving approach is applied subsequently to project data from high-dimensional space to low-dimensional space. Shift invariant DWT can represent image texture information efficiently in combination with a histogram signature,and the local geometrical structure of the dataset is preserved well during clustering. Experimental results show that the proposed method remarkably outperforms traditional ones. 展开更多
关键词 shift invariant DWT. Texture signature Local preserving clustering Dimension reduction k-means
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Asymmetric Multi-channel Sampling in a Series of Shift Invariant Spaces
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作者 Adam Zakria 《Journal of Mathematics and System Science》 2016年第9期352-365,共14页
We show asymmetric multi-channel sampling on a series of a shift invariant spaces ∑a^m=1v(φ(ta)) with a series of Riesz generators ∑a^m=1φ(ta) in L2(R), where each channeled signal is assigned a uniform bu... We show asymmetric multi-channel sampling on a series of a shift invariant spaces ∑a^m=1v(φ(ta)) with a series of Riesz generators ∑a^m=1φ(ta) in L2(R), where each channeled signal is assigned a uniform but distinct sampling rate. We use Fourier duality between ∑a^m=1v(φ(ta))and L2[0, 2π] to find conditions under which there is a stable asymmetric multi-channel sampling formula on ∑a^m=1v(φ(ta)). 展开更多
关键词 shift invariant space Multi-channel sampling Frame Riesz basis
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Generalized Sampling in Shift Invariant Spaces with Frames 被引量:1
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作者 Stefan ERICSSON 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2012年第9期1823-1844,共22页
Generalized sampling in a shift invariant subspace V of L2(R) is considered. A function f in V is processed with different filters Lm and then one tries to reconstruct f from the samples L^mf(j'k). We develop a t... Generalized sampling in a shift invariant subspace V of L2(R) is considered. A function f in V is processed with different filters Lm and then one tries to reconstruct f from the samples L^mf(j'k). We develop a theory of how to do this in the case when V possesses a shift invariant frame. Special attention is paid to the question: How to obtain dual frames with compact support? 展开更多
关键词 Generalized sampling FRAMES Riesz basis reproducing kernel shift invariant spaces
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Rank-One Cross Commutators on Backward Shift Invariant Subspaces on the Bidisk 被引量:1
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作者 Kei Ji IZUCHI Kou Hei IZUCHI 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2009年第5期693-714,共22页
For a backward shift invariant subspace N in H^2(Г^2), the operators Sz and Sw on N are defined by Sz = PNTz|N and Sw, = PNTw|N, where PN is the orthogonal projection from L^2(Г^2) onto N. We give a characteri... For a backward shift invariant subspace N in H^2(Г^2), the operators Sz and Sw on N are defined by Sz = PNTz|N and Sw, = PNTw|N, where PN is the orthogonal projection from L^2(Г^2) onto N. We give a characterization of N satisfying rank [Sz, Sw^*] = 1. 展开更多
关键词 backward shift invariant subspace invariant subspace Hardy space cross commutator rank-one operator
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Summation and intersection of refinable shift invariant spaces
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作者 DAI XinRong SONG JunQuan 《Science China Mathematics》 SCIE 2011年第10期2087-2097,共11页
We study shift invariant spaces generated by refinable distributions. We classify the summation and the intersection of shift invariant spaces generated by refinable distributions,and prove that they are also shift in... We study shift invariant spaces generated by refinable distributions. We classify the summation and the intersection of shift invariant spaces generated by refinable distributions,and prove that they are also shift invariant spaces generated by refinable distributions. 展开更多
关键词 refinable distribution shift invariant space linearly independent property
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Exact Solutions of Variation Problem on Shiftability of Principal Shift Invariant Spaces
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作者 Wang Qiao Department of Mathematics, Wuhan University, Wuhan 430072,China Information Science Center, Beijing University,Beijing 100871, China 《Wuhan University Journal of Natural Sciences》 CAS 1997年第1期11-14,共4页
A complete answer to the shiftability of a principal shift invariant spaces and a scaled version is given. The congruence of spectrum plays a kernel role. It characterizes essentially the shiftability and the scale ... A complete answer to the shiftability of a principal shift invariant spaces and a scaled version is given. The congruence of spectrum plays a kernel role. It characterizes essentially the shiftability and the scale of any principal shift variant spaces. Some examples relative to signal analysis are discussed associated with an explanation to the failure of generalizing Shannon s sampling theorem from band limitted to band pass case. 展开更多
关键词 principal shift invariant space shiftability congruence of spectrum
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The Properties of Finitely Generated Shift-invariant Subspace in L_(2π)~2
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作者 薛明志 朱秀阁 田继善 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期69-75, ,共7页
In this paper, some properties of shift invariant subspace in Periodic wavelets theory are discussed.
关键词 shift invariant subspace periodic wavelets dual element
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Shift Invariance Level Comparison of Several Contourlet Transforms and Their Texture Image Retrieval Systems
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作者 Xinwu Chen Jingjing Xue +1 位作者 Zhen Liu Wenjuan Ma 《Journal of Signal and Information Processing》 2016年第1期1-6,共6页
In this paper, we proposed a metric to measure the shift invariance of the three different contourlet transforms. And then, using the same structure texture image retrieval system which use subband coefficients energy... In this paper, we proposed a metric to measure the shift invariance of the three different contourlet transforms. And then, using the same structure texture image retrieval system which use subband coefficients energy, standard deviation and kurtosis features with Canberra distance, we gave a comparison of their texture description abilities. Experimental results show that contourlet-2.3 texture image retrieval system has almost retrieval rates with non-sub sampled contourlet system;the two systems have better retrieval results than the original contourlet retrieval system. On the other hand, for the relatively lower redundancy, we recommend using contourlet- 2.3 as texture description transform. 展开更多
关键词 Content Based Texture Image Retrieval shift Invariance Level Contourlet Transform Contourlet-2.3
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Linearity of Removal in the Proeess of Optical Element Polishing
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作者 辛企明 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期122-131,共10页
In the light of some assumptions that are very close to the practical working conditions,a very complicated polishing process of optical element can be simplified as a linear and shift invariant system that is relatd ... In the light of some assumptions that are very close to the practical working conditions,a very complicated polishing process of optical element can be simplified as a linear and shift invariant system that is relatd only to the speed,pres- sure and time of processing.In polishing,the removed material can be represented and entreated by the convolution of the removal function of polishing head and the dwell function.The properties of removal function are presented.The assumptions and methods given by the author have been shown to be correct and applicable by experiments using a ring lap to polish the optical surfac. 展开更多
关键词 optical element POLISHING convolution/linear and shift invariant system
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如何在通用人工智能系统中实现“知识锁定标杆浮动效应”——一种基于“时间压力”的简易心智模型 被引量:2
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作者 徐英瑾 《武汉大学学报(哲学社会科学版)》 CSSCI 北大核心 2019年第5期54-66,共13页
所谓“知识锁定标杆浮动效应”,是指面对同样的信念内容,认知主体会在某些环境下将其判定为“知识”,而在另一些环境下将其判定为“非知识”。该效应的存在,使得人类能够根据环境信息的变化,灵活地改变自身信念,更好地适应环境。人工智... 所谓“知识锁定标杆浮动效应”,是指面对同样的信念内容,认知主体会在某些环境下将其判定为“知识”,而在另一些环境下将其判定为“非知识”。该效应的存在,使得人类能够根据环境信息的变化,灵活地改变自身信念,更好地适应环境。人工智能体对于该效应机制的模拟,也能够更好地适应环境。不过,这种模拟必须建立在对于该效应的正确理解上,而西方主流知识论学界对于该效应的解释,如语境主义、比对主义与不变主义提出的解释,要么缺乏足够的普遍性,要么本身建立在一些有待解释的概念上。与之相比较,基于“时间压力”的模型,则将智能体的知识指派倾向的强度视为与其感受的时间压力彼此负相关的一项因素,而“时间压力”本身被视为“主体所预估的问题解决所需要的时间”与其“所愿意付出且能够付出的时间”之间的差值。这样的模型不仅能够对所谓的“银行案例”与“斑马案例”作出简洁的解释,而且在原则上可以被算法化。 展开更多
关键词 通用人工智能 时间压力 知识锁定标杆浮动效应 比对主义 语境主义 不变主义 固知需求
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一种关于“判知结论浮动”现象的多元主义解释框架
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作者 徐英瑾 《武汉大学学报(哲学社会科学版)》 CSSCI 北大核心 2021年第5期5-15,共11页
“判知结论浮动”指的是面对同样的信念,只要产生这个信念的内外条件发生了变化,知识裁判人就会对这个信念本身的知识地位做出不同的评估。英美知识论学界用于解释判知结论浮动的主流理论,包括语境主义、比对主义、不变主义,等等。这些... “判知结论浮动”指的是面对同样的信念,只要产生这个信念的内外条件发生了变化,知识裁判人就会对这个信念本身的知识地位做出不同的评估。英美知识论学界用于解释判知结论浮动的主流理论,包括语境主义、比对主义、不变主义,等等。这些理论都可以被顺化为一个统一的概率学框架。根据这一框架,一个信念P的知识地位的稳固程度,取决于这个信念本身抵御其“异常使真者”之颠覆的能力,抵御力的大小,也可以得到概率学的表征。“异常使真者”能引导主体产生P的信念,却又不是直接与P对应的那个“正常事实”,而是某个非常反常的、其出现又具有极大偶然性的事实,因此,“异常使真者”的引入是会削弱信念P的知识地位的。不过,对于到底哪些具体的认知因素可以充当“异常使真者”这一点,统一框架持一种多元主义的态度,亦能够方便我们在哲学层面上以多元主义态度应对各种关于判知结论浮动的成因。西方学界针对判知结论浮动问题的主流解释方略,往往夸大某个导致判知结论浮动的因素的影响力,忽略了其他成因,难免陷入“盲人摸象”之境地。 展开更多
关键词 概率 判知结论浮动 语境主义 不变主义 固知需求 异常使真者
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EIGENPROBLEM OF SUBSTRUCTURE CHAIN AND THE EXPANSION SOLUTION 被引量:1
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作者 Zhong Wanxie Lin Jiahao Qiu Chunhang (Dalian University of Technology Winning Software System Engineering Ltd.) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1991年第2期169-177,共9页
In this paper,a new method for dealing with substructure chain is presented.Here,a substructure chain means a structure consisting of a number of identical substructures connected in series.This method is parallel to ... In this paper,a new method for dealing with substructure chain is presented.Here,a substructure chain means a structure consisting of a number of identical substructures connected in series.This method is parallel to the expansion method in the structural analysis according to the transverse section.The method of shift invariance and that of initial parameter and transfer matrix,their mutual-relation and com- bined use,as well as the analysis of the eigenproblem on the transverse section,and the expansion method based on the eigenvectors are described in this paper. 展开更多
关键词 substructure chain shift invariance TRANSFER
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Automatic Collecting Representative Logo Images from the Internet 被引量:2
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作者 Xiaobing Liu Bo Zhang 《Tsinghua Science and Technology》 SCIE EI CAS 2013年第6期606-617,共12页
With the explosive growth of commercial Iogos, high quality logo images are needed for training logo detection or recognition systems, especially for famous Iogos or new commercial brands. This paper focuses on automa... With the explosive growth of commercial Iogos, high quality logo images are needed for training logo detection or recognition systems, especially for famous Iogos or new commercial brands. This paper focuses on automatic collecting representative logo images from the internet without any human labeling or seed images. We propose multiple dictionary invariant sparse coding to solve this problem. This work can automatically provide prototypes, representative images, or weak labeled training images for logo detection, logo recognition, trademark infringement detection, brand protection, and ad-targeting. The experiment results show that our method increases the mean average precision for 25 types of Iogos to 80.07% whereas the original search engine results only have 32% representative logo images. The top images collected by our method are accurate and reliable enough for practical applications in the future. 展开更多
关键词 logo image sparse coding scale invariant shift invariant multiple dictionary
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Sparse approximate solution of fitting surface to scattered points by MLASSO model 被引量:2
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作者 Yongxia Hao Chongjun Li Renhong Wang 《Science China Mathematics》 SCIE CSCD 2018年第7期1319-1336,共18页
The goal of this paper is to achieve a computational model and corresponding efficient algorithm for obtaining a sparse representation of the fitting surface to the given scattered data. The basic idea of the model is... The goal of this paper is to achieve a computational model and corresponding efficient algorithm for obtaining a sparse representation of the fitting surface to the given scattered data. The basic idea of the model is to utilize the principal shift invariant(PSI) space and the l_1 norm minimization. In order to obtain different sparsity of the approximation solution, the problem is represented as a multilevel LASSO(MLASSO)model with different regularization parameters. The MLASSO model can be solved efficiently by the alternating direction method of multipliers. Numerical experiments indicate that compared to the AGLASSO model and the basic MBA algorithm, the MLASSO model can provide an acceptable compromise between the minimization of the data mismatch term and the sparsity of the solution. Moreover, the solution by the MLASSO model can reflect the regions of the underlying surface where high gradients occur. 展开更多
关键词 sparse solution principle shift invariant space l1 norm minimization alternating direction method multipliers MLASSO model
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