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基于子块分类的BP神经网络图像压缩 被引量:2
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作者 刘洋 唐向宏 余志卫 《杭州电子科技大学学报(自然科学版)》 2009年第2期32-35,共4页
该文介绍了BP神经网络用于图像压缩的原理和基本模型,提出了一种基于子块分类的改进BP神经网络图像压缩算法:将图像子块分成背景子块、目标子块和边缘子块,结合各类子块的灰度变化特征、边缘特征以及人眼的视觉分辨特点,对各类子块分别... 该文介绍了BP神经网络用于图像压缩的原理和基本模型,提出了一种基于子块分类的改进BP神经网络图像压缩算法:将图像子块分成背景子块、目标子块和边缘子块,结合各类子块的灰度变化特征、边缘特征以及人眼的视觉分辨特点,对各类子块分别采用不同的隐含层节点数,从而保证重建图像有较好的边缘细节和主观质量。实验结果证明本算法在取得较大的压缩比的同时恢复图像能有较好的质量。 展开更多
关键词 神经网络 图像压缩 子块分类 视觉特征
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基于分类子块的图像检索 被引量:1
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作者 胡一君 邹北骥 《计算机工程与科学》 CSCD 2006年第7期62-64,共3页
图像等分成M×N块后,将子块分成背景子块、目标子块和边缘子块三类,并从中提取颜色、空间特征和边缘特征,求图像间相似度时只在同类子块之间进行匹配。这样既减少了匹配运算量,又可避免不同类子块匹配所产生的干扰。实验结果表明,... 图像等分成M×N块后,将子块分成背景子块、目标子块和边缘子块三类,并从中提取颜色、空间特征和边缘特征,求图像间相似度时只在同类子块之间进行匹配。这样既减少了匹配运算量,又可避免不同类子块匹配所产生的干扰。实验结果表明,该方法不仅求图像间相似度的运算量小,而且对图像的旋转和平移变化不敏感,具有较好的检索性能。 展开更多
关键词 基于内容的图像检索 分类 相似度
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图像边缘信息的谱分析及其在变换编码中的应用 被引量:5
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作者 谭雁英 董志信 《电子学报》 EI CAS CSCD 北大核心 1995年第9期61-65,共5页
本文对边缘信息的DCT频谱特征做了分析。通过理论推导及事例分析证得含平直单边缘图像子块,其DCT变换系数能量并不总是集中分布在与其空间边缘走向垂直的方向上。将研究结果应用于变换编码的分类环节,提出一种按边缘信息的频谱... 本文对边缘信息的DCT频谱特征做了分析。通过理论推导及事例分析证得含平直单边缘图像子块,其DCT变换系数能量并不总是集中分布在与其空间边缘走向垂直的方向上。将研究结果应用于变换编码的分类环节,提出一种按边缘信息的频谱特性分类的方法,实验结果表明了该方法的有效性。 展开更多
关键词 图像边缘 频谱特征 子块分类 变换编码
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Geometrical Langlands Ramifications and Differential Operators Classification by Coherent D-Modules in Field Theory 被引量:2
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作者 Francisco Bulnes 《Journal of Mathematics and System Science》 2013年第10期491-507,共17页
Spaces of equivalence modulo a relation of congruence are constructed on field solutions to establish a theory of the universe that includes the theory QFT (Quantum Field theory), the SUSY (Super-symmetry theory) ... Spaces of equivalence modulo a relation of congruence are constructed on field solutions to establish a theory of the universe that includes the theory QFT (Quantum Field theory), the SUSY (Super-symmetry theory) and HST (heterotic string theory) using the sheaves correspondence of differential operators of the field equations and sheaves of coherent D - Modules [1]. The above mentioned correspondence use a Zuckerman functor that is a factor of the universal functor of derived sheaves of Harish-Chandra to the Langlands geometrical program in mirror symmetry [2, 3]. The obtained development includes complexes of D - modules of infinite dimension, generalizing for this way, the BRST-cohomology in this context. With it, the class of the integrable systems is extended in mathematical physics and the possibility of obtaining a general theory of integral transforms for the space - time (integral operator cohomology [4]), and with it the measurement of many of their observables [5]. Also tends a bridge to complete a classification of the differential operators for the different field equations using on the base of Verma modules that are classification spaces of SO(l, n + 1), where elements of the Lie algebra al(1, n + 1), are differential operators, of the equations in mathematical physics [1]. The cosmological problem that exists is to reduce the number of field equations that are resoluble under the same gauge field (Verma modules) and to extend the gauge solutions to other fields using the topological groups symmetries that define their interactions. This extension can be given by a global Langlands correspondence between the Hecke sheaves category on an adequate moduli stack and the holomorphic L G - bundles category with a special connection (Deligne connection). The corresponding D - modules may be viewed as sheaves of conformal blocks (or co-invariants) (images under a version of the Penrose transform [1, 6]) naturally arising in the framework of conformal field theory. 展开更多
关键词 Langlands correspondence Hecke sheaves category moduli stacks Verma modules generalized D-modules Vermamodule extensions
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Classification of Quasifinite Modules with Nonzero Central Charges for EALAs of Type A with Coordinates in Quantum Torus
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作者 Rencai LV 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2009年第2期129-138,共10页
The author first constructs a Lie algebra ∑ :=∑(q, Wd) from rank 3 quantum torus, which is isomorphic to the core of EALAs of type Ad-1 with coordinates in quantum torus Cqd, and then gives the necessary and suff... The author first constructs a Lie algebra ∑ :=∑(q, Wd) from rank 3 quantum torus, which is isomorphic to the core of EALAs of type Ad-1 with coordinates in quantum torus Cqd, and then gives the necessary and sufficient conditions for the highest weight modules to be quasifinite nonzero central charges are Finally the irreducible Z-graded quasifinite ∑-modules with classified. 展开更多
关键词 Core of EALAs Graded modules Quasifinite module Highest weightmodule Quantum torus
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The φ-Group for n Submodules Systems as a Generalization of the K-Theory
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作者 Dong LI Xiaoman CHEN Shengzhi XU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第1期101-114,共14页
In this paper,the authors construct a φ-group for n submodules,which generalizes the classical K-theory and gives more information than the classical ones.This theory is related to the classification theory for indec... In this paper,the authors construct a φ-group for n submodules,which generalizes the classical K-theory and gives more information than the classical ones.This theory is related to the classification theory for indecomposable systems of n subspaces. 展开更多
关键词 System of n subspaces System of n submodules Ф-Group K-THEORY Indecomposable system
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