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A Note on Unification of Translational Shape Invariant Potential and Scaling Shape Invariant Potential
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作者 HUANG Bo-Wen GU Zhi-Yu QIAN Shang-Wu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期619-621,共3页
This article puts forward a general shape invariant potential, which includes the translational shape invariant potential and scaling shape invariant potential as two particular cases, and derives the set of linear di... This article puts forward a general shape invariant potential, which includes the translational shape invariant potential and scaling shape invariant potential as two particular cases, and derives the set of linear differential equations for obtaining general solutions of the generalized shape invariance condition. 展开更多
关键词 translational shape invariant potential scaling shape invariant potential
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Generation and classification of the translational shape-invariant potentials based on the analytical transfer matrix method
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作者 桑明煌 余子星 +1 位作者 李翠翠 涂凯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期52-56,共5页
For the conventional translational shape-invariant potentials (TSIPs), it has demonstrated that the phase contribution devoted by the scattered subwaves in the analytical transfer matrix quantization condition is in... For the conventional translational shape-invariant potentials (TSIPs), it has demonstrated that the phase contribution devoted by the scattered subwaves in the analytical transfer matrix quantization condition is integrable and independent of n. Based on this fact we propose a novel strategy to generate the whole set of conventional TSIPs and classify them into three types. The generating functions are given explicitly and the Morse potential is taken as an example to illustrate this strategy. 展开更多
关键词 translational shape-invariant potentials supersymmetric quantum mechanics analyticaltransfer matrix method scattered subwaves generating function
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TRANSLATION-INVARIANT BASED ADAPTIVE THRESHOLD DENOISING FOR IMPACT SIGNAL 被引量:4
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作者 GaiGuanghong QuLiangsheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期552-555,共4页
A translation-invariant based adaptive threshold denoising method formechanical impact signal is proposed. Compared with traditional wavelet denoising methods, itsuppresses pseudo-Gibbs phenomena in the neighborhood o... A translation-invariant based adaptive threshold denoising method formechanical impact signal is proposed. Compared with traditional wavelet denoising methods, itsuppresses pseudo-Gibbs phenomena in the neighborhood of signal discontinuities. To remedy thedrawbacks of conventional threshold functions, a new improved threshold function is introduced. Itpossesses more advantages than others. Moreover, based on utilizing characteristics of signal, aadaptive threshold selection procedure for impact signal is proposed. It is data-driven andlevel-dependent, therefore, it is more rational than other threshold estimation methods. Theproposed method is compared to alternative existing methods, and its superiority is revealed bysimulation and real data examples. 展开更多
关键词 translation-invariant Adaptive threshold Impact signal DENOISING Wavelettransform
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The Translation Invariant Contourlet-like Transform for Image Denoising 被引量:3
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作者 LIAN Qiu-Sheng CHEN Shu-Zhen 《自动化学报》 EI CSCD 北大核心 2009年第5期505-508,共4页
关键词 滤波技术 滤波器 图像 降噪
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Translation invariant tensor product states in a finite lattice system
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作者 蔡建伟 陈巧妮 +4 位作者 赵汇海 谢志远 秦明普 魏忠超 向涛 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期479-486,共8页
We show that the matrix (or more generally tensor) product states in a finite translation invariant system can be accurately constructed from a same set of local matrices (or tensors) that are determined from an i... We show that the matrix (or more generally tensor) product states in a finite translation invariant system can be accurately constructed from a same set of local matrices (or tensors) that are determined from an infinite lattice system in one or higher dimensions. This provides an efficient approach for studying translation invariant tensor product states in finite lattice systems. Two methods are introduced to determine the size-independent local tensors. 展开更多
关键词 tensor product state translation invariant
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Comparison of MRI Under-Sampling Techniques for Compressed Sensing with Translation Invariant Wavelets Using FastTestCS: A Flexible Simulation Tool
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作者 Christopher Baker 《Journal of Signal and Information Processing》 2016年第4期252-271,共20页
A sparsifying transform for use in Compressed Sensing (CS) is a vital piece of image reconstruction for Magnetic Resonance Imaging (MRI). Previously, Translation Invariant Wavelet Transforms (TIWT) have been shown to ... A sparsifying transform for use in Compressed Sensing (CS) is a vital piece of image reconstruction for Magnetic Resonance Imaging (MRI). Previously, Translation Invariant Wavelet Transforms (TIWT) have been shown to perform exceedingly well in CS by reducing repetitive line pattern image artifacts that may be observed when using orthogonal wavelets. To further establish its validity as a good sparsifying transform, the TIWT is comprehensively investigated and compared with Total Variation (TV), using six under-sampling patterns through simulation. Both trajectory and random mask based under-sampling of MRI data are reconstructed to demonstrate a comprehensive coverage of tests. Notably, the TIWT in CS reconstruction performs well for all varieties of under-sampling patterns tested, even for cases where TV does not improve the mean squared error. This improved Image Quality (IQ) gives confidence in applying this transform to more CS applications which will contribute to an even greater speed-up of a CS MRI scan. High vs low resolution time of flight MRI CS re-constructions are also analyzed showing how partial Fourier acquisitions must be carefully addressed in CS to prevent loss of IQ. In the spirit of reproducible research, novel software is introduced here as FastTestCS. It is a helpful tool to quickly develop and perform tests with many CS customizations. Easy integration and testing for the TIWT and TV minimization are exemplified. Simulations of 3D MRI datasets are shown to be efficiently distributed as a scalable solution for large studies. Comparisons in reconstruction computation time are made between the Wavelab toolbox and Gnu Scientific Library in FastTestCS that show a significant time savings factor of 60×. The addition of FastTestCS is proven to be a fast, flexible, portable and reproducible simulation aid for CS research. 展开更多
关键词 Compressed Sensing translation invariant Wavelet Simulation Software Total Variation l1 Minimization
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Binding Energy, Root Mean Square Radius and Magnetic Dipole Moment of the Triton Nucleus
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作者 Khadija Abdelhassan Kharroube 《Open Journal of Microphysics》 2024年第2期24-39,共16页
The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tens... The basis functions of the translation invariant shell model are used to construct the ground state nuclear wave functions of <sup>3</sup>H. The used residual two-body interactions consist of central, tensor, spin orbit and quadratic spin orbit terms with Gaussian radial dependence. The parameters of these interactions are so chosen in such a way that they represent the long-range attraction and the short-range repulsion of the nucleon-nucleon interactions. These parameters are so chosen to reproduce good agreement between the calculated values of the binding energy, the root mean-square radius, the D-state probability, the magnetic dipole moment and the electric quadrupole moment of the deuteron nucleus. The variation method is then used to calculate the binding energy of triton by varying the oscillator parameter which exists in the nuclear wave function. The obtained nuclear wave functions are then used to calculate the root mean-square radius and the magnetic dipole moment of the triton. 展开更多
关键词 translation invariant Shell Model Residual Two-Body Interactions Nucleon-Nucleon Interactions Binding Energy Nuclear Wave Functions
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Human CD4- CD8- Invariant Natural Killer T Cells Promote IgG Secretion from B Cells Stimulated by Cross-Linking of Their Antigen Receptors
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作者 Tomomitsu Miyasaka Yurie Watanabe +7 位作者 Yukiko Akahori Namiko Miyamura Keiko Ishii Yuki Kinjo Yoshitsugu Miyazaki Tian-Yi Liu Yasushi Uemura Kazuyoshi Kawakami 《World Journal of Vaccines》 2016年第2期34-41,共8页
Immunoglobulin (Ig) M production can be induced by the interaction of thymus-independent type-2 (TI-2) antigen (Ag) with B cell Ag receptors (BCRs) without the involvement of conventional T cells;for IgG production th... Immunoglobulin (Ig) M production can be induced by the interaction of thymus-independent type-2 (TI-2) antigen (Ag) with B cell Ag receptors (BCRs) without the involvement of conventional T cells;for IgG production through the same process, however, a second signal is required. Previous studies have reported that invariant natural killer T (iNKT) cells may be responsible for the second signal involved in IgG production. In the present study, we addressed whether human iNKT cells could participate in the production of Ig against TI-2 Ag in vitro. Two major distinct subsets of human iNKT cells, CD4<sup>+</sup> CD8β<sup>-</sup> (CD4) and CD4<sup>-</sup> CD8β<sup>-</sup> [double negative (DN)] cells, were generated from peripheral blood monocytes from a healthy volunteer. BCR engagement, triggered by anti-IgM antibody stimulation, examined here as a model of BCR engagement triggered by TI-2 Ag, induced abundant IgM production by B cells. Both CD4 and DN iNKT cells reduced IgM production and conversely enhanced IgG production in a dose-dependent manner. In addition, IgG production by CD19<sup>+</sup>CD27<sup>-</sup> (naïve) and CD19<sup>+</sup>CD27<sup>+</sup> (memory) B cells was predominantly promoted by DNiNKT cells rather than CD4 iNKT cells;nevertheless, IgM production by both B cell subsets was similarly reduced by either subset of iNKT cells. These results suggest that the DN iNKT subsets may preferentially promote Ig class switching by B cells upon stimulation with TI-2 Ag. 展开更多
关键词 invariant Natural Killer T Cells ti-2 Antigen B Cells IGM IGG
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轻小型SAR卫星平飞模式设计
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作者 范军 陈筠力 +3 位作者 肖锋 黄欣 黄智 刘艳阳 《上海航天(中英文)》 CSCD 2024年第2期154-160,共7页
对于轻小型合成孔径雷达(SAR)卫星在轨使用时对重点区域多目标观测效能提升的需求,提出轻小型SAR卫星平飞模式设计方法。介绍了卫星平飞模式设计方法,提出载荷平面相控阵天线距离维大角度扫描能力设计;针对区域多目标,提出条件触发方式... 对于轻小型合成孔径雷达(SAR)卫星在轨使用时对重点区域多目标观测效能提升的需求,提出轻小型SAR卫星平飞模式设计方法。介绍了卫星平飞模式设计方法,提出载荷平面相控阵天线距离维大角度扫描能力设计;针对区域多目标,提出条件触发方式目标决策策略,以及星上雷达工作参数计算策略;基于建立的目标决策和任务规划模型,分别针对卫星左侧视、在侧视、平飞、左右机动侧视等4种工作模式下进行多目标观测效能评估仿真分析。结果表明:相比于卫星斜飞模式下,平飞模式目标观测效能可提升至41%;相比于卫星左右机动侧视模式下,平飞模式目标观测效能可提升至73%。因此,设计的卫星平飞模式可有效提升面向区域多目标的观测效能。 展开更多
关键词 星载SAR 平飞模式 任务规划 多目标 效能提升
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改进阈值的TI小波去噪法在MT去噪中的应用 被引量:3
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作者 曹小玲 严良俊 陈清礼 《物探与化探》 CAS CSCD 北大核心 2018年第3期600-607,共8页
在测量电场和磁场分量的过程中,由于地质因素、工频、人文干扰和其他外界因素以及观测系统所造成的干扰等,常常会使实际数据含有噪声,从而影响到视电阻率和相位的计算以及后续的正反演工作。为提高处理效果,在已有快速算法的基础上,将... 在测量电场和磁场分量的过程中,由于地质因素、工频、人文干扰和其他外界因素以及观测系统所造成的干扰等,常常会使实际数据含有噪声,从而影响到视电阻率和相位的计算以及后续的正反演工作。为提高处理效果,在已有快速算法的基础上,将改进阈值的TI小波去噪法应用在大地电磁信号去噪中。利用该方法对大地电磁信号去噪,可以达到既有效去除噪声又较大程度地维持原始信号形态的目的。在对实测大地电磁数据进行去噪处理后的结果显示,该去噪方法使信号数据的突变现象得到有效的控制和减少,并使时间序列、视电阻率曲线和相位曲线的质量都有了明显的改善,因而具有较好的去噪效果。 展开更多
关键词 小波分析 去噪 平移不变量 大地电磁信号
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基于边界约束最优投影梯度NMF的TINST域图像融合方法 被引量:1
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作者 才华 陈广秋 +2 位作者 刘广文 耿朕野 杨勇 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2016年第5期1087-1095,共9页
针对多模态图像的融合问题,提出一种平移不变不可分离剪切波结合边界约束最优投影梯度非负矩阵分解的图像融合方法,解决了已有融合方法中融合精度较低的问题.该方法利用平移不变不可分离剪切波对源图像进行分解;将低频子带系数视为原始... 针对多模态图像的融合问题,提出一种平移不变不可分离剪切波结合边界约束最优投影梯度非负矩阵分解的图像融合方法,解决了已有融合方法中融合精度较低的问题.该方法利用平移不变不可分离剪切波对源图像进行分解;将低频子带系数视为原始观测数据,采用边界约束最优投影梯度非负矩阵分解算法得到包含特征基的融合低频子带系数,将高频方向子带系数作为脉冲耦合神经网络的外部输入激励,边缘强度作为链接强度,经点火处理和判决选择运算,得到融合高频方向子带系数;最后对融合子带进行平移不变不可分离剪切波逆变换得到融合图像.为了验证该融合方法的有效性,对几组不同模态的图像进行对比融合实验.融合图像的主观与客观评价结果表明,该融合方法优于目前已有的典型多尺度图像融合方法. 展开更多
关键词 平移不变不可分离剪切波变换 融合准则 非负矩阵分解 脉冲耦合神经网络
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基于项目相关度的STI新群体冷启动推荐方法 被引量:1
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作者 王磊 赵庆建 罗兴峰 《小型微型计算机系统》 CSCD 北大核心 2015年第3期450-453,共4页
针对推荐系统中相似偏好用户数量较少情况下的一类新群体冷启动问题开展研究,基于多元相关分析,对传统的尺度与平移不变(Scale and Translation Invariant,STI)的协同过滤推荐方法进行改进,提出一种基于项目相关度的STI推荐方法,以应对... 针对推荐系统中相似偏好用户数量较少情况下的一类新群体冷启动问题开展研究,基于多元相关分析,对传统的尺度与平移不变(Scale and Translation Invariant,STI)的协同过滤推荐方法进行改进,提出一种基于项目相关度的STI推荐方法,以应对推荐系统中的新群体冷启动问题.在此基础上,基于Movie Lens数据集对所提出的方法进行了性能分析,结果表明,所提出的方法较Pearson方法及ST1N1方法在解决新群体冷启动推荐的过程中具有更高的推荐准确率. 展开更多
关键词 推荐系统 冷启动 新群体 项目相关度 尺度与平移不变
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High-visibility ghost imaging with phase-controlled discrete classical light sources
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作者 仵雪滢 赵岳 李利明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期328-334,共7页
We take phase modulation to create discrete phase-controlled sources and realize the super-bunching effect by a phasecorrelated method. From theoretical and numerical simulations, we find the space translation invaria... We take phase modulation to create discrete phase-controlled sources and realize the super-bunching effect by a phasecorrelated method. From theoretical and numerical simulations, we find the space translation invariance of the bunching effect is a key point for the ghost imaging realization. Experimentally, we create the orderly phase-correlated discrete sources which can realize high-visibility second-order ghost imaging than the result with chaotic sources. Moreover, some factors affecting the visibility of ghost image are discussed in detail. 展开更多
关键词 ghost imaging high visibility space translation invariance
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簸箕型流道泵站水泵振动信号消噪方法研究
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作者 李彦迪 王昱 《机械制造与自动化》 2024年第5期92-96,共5页
为解决水泵信号振源复杂、含噪量大,难以在信号内获得有效数据的问题,研究一种基于改进平移不变量小波阈值的振动信号消噪方法。将水泵振动信号划分为信号高频区域和低频区域,选取对应合适的小波范围,在小波分解层数作用下正交变换含噪... 为解决水泵信号振源复杂、含噪量大,难以在信号内获得有效数据的问题,研究一种基于改进平移不变量小波阈值的振动信号消噪方法。将水泵振动信号划分为信号高频区域和低频区域,选取对应合适的小波范围,在小波分解层数作用下正交变换含噪信号。利用阈值限制小波系数完成滤波,通过设定噪声标准偏差值,求得振动信号小波系数中间值,实现信号重构。将振动信号含噪部分在时域空间完成循环平移,填补信号不连续缺陷部位,平移去噪后计算振动信号平均值,得到最终消噪振动信号。仿真分析结果显示:该方法在平移不变量的辅助下,可填补信号不连续缺陷点,从噪声中恢复出原始振动信号,波形的失真较小,信号信噪比较高,鲁棒性好,可完整地保存信号的轮廓和特征。为分析簸箕型进水流道内部流态提供新思路,保证水泵整体工作可靠性。 展开更多
关键词 振动信号消噪 水泵振动 小波系数 正交变换 平移不变量
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基于TI-DWT-MSSNF的谱光滑与评价
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作者 李磊 庹先国 +2 位作者 刘明哲 石睿 王俊 《核技术》 CAS CSCD 北大核心 2014年第12期16-22,共7页
提出了基于平移不变离散小波变换(Translation Invariant Discrete Wavelet Transform,TI-DWT)小波模极大值空间选择性滤波(Translation Invariant Discrete Wavelet Transform Wavelet Modulus Maxima Spatial Selectivity Filter,TI-D... 提出了基于平移不变离散小波变换(Translation Invariant Discrete Wavelet Transform,TI-DWT)小波模极大值空间选择性滤波(Translation Invariant Discrete Wavelet Transform Wavelet Modulus Maxima Spatial Selectivity Filter,TI-DWT-MSSNF)的能谱平滑算法,并构建了光滑效果评价指标。分别使用α谱仪和γ谱仪获取了239Pu、241Am的α能谱和137Cs的γ能谱,将5点3次多项式最小二乘法、传统的小波模极大值法和TI-DWT-MSSNF分别用于α和γ谱平滑处理。结果表明:相比较5点3次多项式最小二乘法和传统的小波模极大值法,TI-DWT-MSSNF消除统计涨落更加彻底,特征信息保留更好,峰形畸变更小,是一种更优的方法。 展开更多
关键词 平移不变离散小波变换 模极大值 光滑效果评价
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算子代数上Hermitian双线性泛函表示
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作者 宋海洲 《华侨大学学报(自然科学版)》 CAS 1998年第3期219-224,共6页
在紧支集无穷次可微函数空间,或急速下降无穷次可微函数空间上,给出取值算子代数中的Hermitian双线性泛函的表示,为算子代数上的广义函数提供有用的工具.
关键词 C*-代数 HERMItiAN 双线性泛函 算子代数
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Rotation Scaling and Translation Invariants of 3D Radial Shifted Legendre Moments 被引量:1
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作者 Mostafa El Mallahi Jaouad E1Mekkaoui +2 位作者 Areal Zouhri Hicham Amakdouf Hassan Qjidaa 《International Journal of Automation and computing》 EI CSCD 2018年第2期169-180,共12页
This paper proposes a new set of 3D rotation scaling and translation invariants of 3D radially shifted Legendre moments. We aim to develop two kinds of transformed shifted Legendre moments: a 3D substituted radial sh... This paper proposes a new set of 3D rotation scaling and translation invariants of 3D radially shifted Legendre moments. We aim to develop two kinds of transformed shifted Legendre moments: a 3D substituted radial shifted Legendre moments (3DSRSLMs) and a 3D weighted radial one (3DWRSLMs). Both are centered on two types of polynomials. In the first case, a new 3D ra- dial complex moment is proposed. In the second case, new 3D substituted/weighted radial shifted Legendremoments (3DSRSLMs/3DWRSLMs) are introduced using a spherical representation of volumetric image. 3D invariants as derived from the sug- gested 3D radial shifted Legendre moments will appear in the third case. To confirm the proposed approach, we have resolved three is- sues. To confirm the proposed approach, we have resolved three issues: rotation, scaling and translation invariants. The result of experi- ments shows that the 3DSRSLMs and 3DWRSLMs have done better than the 3D radial complex moments with and without noise. Sim- ultaneously, the reconstruction converges rapidly to the original image using 3D radial 3DSRSLMs and 3DWRSLMs, and the test of 3D images are clearly recognized from a set of images that are available in Princeton shape benchmark (PSB) database for 3D image. 展开更多
关键词 3D radial complex moments 3D radial shifted Legendre radial moments radial shifted Legendre polynomials 3D imagereconstruction 3D rotation scaling translation invariants 3D image recognition computational complexities.
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A GENERALIZATION OF LEBESGUE DIFFERENTIAL THEOREM AND ITS APPLICATION 被引量:2
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作者 周振荣 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期109-113,共5页
The author generalizes the classical Lebesgue differential theorem to the case of rather general metrics. Then. the author applies it to the subelliptic metric to check the integral characterization of Holder continuo... The author generalizes the classical Lebesgue differential theorem to the case of rather general metrics. Then. the author applies it to the subelliptic metric to check the integral characterization of Holder continuous functions related to the metric. 展开更多
关键词 Morrey's space Campanato's space translation-invariance
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The Properties of Expected Scattering and Averaged Scattering and Their Applications to Texture Classification
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作者 WANG Juan ZHAO Jie 《Chinese Quarterly Journal of Mathematics》 2019年第2期138-151,共14页
In order to further improve the effectiveness of image processing,it is necessary that an efficient invariant representation is stable to deformation applied to images.This motivates the study of image representations... In order to further improve the effectiveness of image processing,it is necessary that an efficient invariant representation is stable to deformation applied to images.This motivates the study of image representations defining an Euclidean metric stable to these deformation.This paper mainly focuses on two aspects.On the one hand,in this paper,two properties of expected scattering and averaged scattering,i.e.,Lipschitz continuity and translation invariance,are proved in detail.These properties support that excepted scattering and averaged scattering are invariant,stable and informative representations.On the other hand,the issue of texture classification based on expected scattering and averaged scattering has been analyzed respectively in this study.Energy features,which are based on expected scattering and averaged scattering,are calculated and used for classification.Experimental results show that starting with the seventh feature,the two approaches can achieve good performance in texture image classification. 展开更多
关键词 translatION invariANCE LIPSCHITZ CONtiNUITY Texture image classification EXPECTED SCATTERING Averaged SCATTERING
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Towards Translational Invariance of Total Energywith Finite Element Methods for Kohn-Sham Equation
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作者 Gang Bao Guanghui Hu Di Liu 《Communications in Computational Physics》 SCIE 2016年第1期1-23,共23页
Numerical oscillation of the total energy can be observed when the Kohn-Sham equation is solved by real-space methods to simulate the translational move of an electronic system.Effectively remove or reduce the unphysi... Numerical oscillation of the total energy can be observed when the Kohn-Sham equation is solved by real-space methods to simulate the translational move of an electronic system.Effectively remove or reduce the unphysical oscillation is crucial not only for the optimization of the geometry of the electronic structure,but also for the study of molecular dynamics.In this paper,we study such unphysical oscillation based on the numerical framework in[G.Bao,G.H.Hu,and D.Liu,An h-adaptive fi-nite element solver for the calculations of the electronic structures,Journal of Computational Physics,Volume 231,Issue 14,Pages 4967-4979,2012],and deliver some numerical methods to constrain such unphysical effect for both pseudopotential and all-electron calculations,including a stabilized cubature strategy for Hamiltonian operator,and an a posteriori error estimator of the finite element methods for Kohn-Sham equation.The numerical results demonstrate the effectiveness of our method on restraining unphysical oscillation of the total energies. 展开更多
关键词 translational invariance adaptive finite element methods Kohn-Sham equation unstructured mesh
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