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An Efficient Proximity Point Algorithm for Total-Variation-Based Image Restoration

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Advances in Applied Mathematics and Mechanics 2014年第2期6卷 145-164页

作者： Wei Zhu Shi Shu lizhi cheng School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina Hunan Key Laboratory for Computation and Simulation in Science and Engineering Xiangtan UniversityXiangtan 411105HunanChina Department of Mathematics and Computational Science College of ScienceNational University of Defense TechnologyChangsha 410073HunanChina

In this paper,we propose a fast proximity point algorithm and apply it to total variation(TV)based image *** novel method is derived from the idea of establishing a general proximity point operator framework based on which new first-order schemes for total variation(TV)based image restoration have been *** current algorithms for TV-based image restoration,such as Chambolle’s projection algorithm,the split Bregman algorithm,the Berm´udez-Moreno algorithm,the Jia-Zhao denoising algorithm,and the fixed point algorithm,can be viewed as special cases of the new first-order ***,the convergence of the new algorithm has been analyzed at ***,we make comparisons with the split Bregman algorithm which is one of the best algorithms for solving TV-based image restoration at *** experiments illustrate the efficiency of the proposed algorithms.

关键词： Proximity point operator image restoration total variation first-order schemes.

Reweighted minimization model for MR image reconstruction with split Bregman method

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Science China(Information Sciences) 2012年第9期55卷 2109-2118页

作者： Hui Zhang (1) lizhi cheng (1) JianPing Li (1) 1. Department of Mathematics and Systems Science College of Science National University of Defense and Technology Changsha 410073 China

Magnetic resonance(MR) image reconstruction is to get a practicable gray-scale image from few frequency domain *** this paper,different reweighted minimization models for MR image reconstruction are studied,and a novel model named reweighted wavelet+TV minimization model is *** using split Bregman method,an iteration minimization algorithm for solving this new model is obtained,and its convergence is *** simulations show that the proposed model and its algorithm are feasible and highly efficient.

关键词： reweighed minimization split Bregman method MR image image reconstruction

Hopkinson Effect in Soft Magnetic Materials

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Journal of Materials Science & Technology 2000年第2期16卷 145-147页

作者： Kaiyuan HE, Hui XU, Zhi WANG and lizhi cheng (Department of Materials Science and Engineering, Northeastern University, Shenyang 110006, China) Department of Materials Science and Engineering Northeastern University Shenyang 110006 China

The μi-T curves of the alloy Fe73.5Cu1 Nb3Si13.5B9 in the amorphous state and in the nanocrys-talline state have been investigated. For comparison, μi-T curves of the other two kinds of typical soft magnetic alloys also have been measured. It was found that a sharp Hopkinson peak appeared at the Curie point for each amorphous and crystalline alloy but there was no Hopkinson peak for the nanocrystalline alloy at the Curie point of the residual amorphous phase. This phenomenon has been explained in terms of the characteristic temperature dependence of the effective magnetic anisotropy.

关键词： Hopkinson Effect in Soft Magnetic Materials

Mechanical Alloying of Fe_(100-x)B_x

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Journal of Materials Science & Technology 1997年第3期13卷 230-232页

作者： lizhi cheng Wei FENG Xinquan DONG Kuichang BAI and Kaiyuan HE (Dept. of Materials Science and Engineering, Northeastern University Shenyang 110006, China) Dept. of Materials Science and Engineering Northeastern University Shenyang 110006 China

The formation of nonequilibrium phase by mechanical alloying (MA) of Fe and B powders in a high energy vibration ball mill has been made for Fe100-xBx system with x=15. 30, 35, 45,55 and 70. By using the X-ray diffraction, magnetic measurement and M6ssbauer spectrummethods, it was revealed that the structure of the MA product varies with milling time and B contents.

关键词： Mechanical Alloying of Fe x)B_x

Structure and Magnetic Properties of Fe_(76.5)Si_(13.5)B_9Cu_1 Alloy with Nanoscale Grain Size

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Journal of Materials Science & Technology 1994年第6期10卷 430-434页

作者： Fei ZHOU Kaiyuan HE lizhi cheng and Zuhan LAI(Dept. of Materials Science and Engineering, Northeastern University, Shenyang, 110006, China)( Dept. of Phys., Northeastern University) Northeastern Univ Shenyang China

The structure and magnetic properties of Fe76.5Si13.5B9Cu1 alloys with a nanocrystalline (NC) bcc Fe(Si) phase trom about 23 to 46 nm in diameter, which were first formed into amorphous ribbons and then annealed at various temperatures between 703 and 773 K, have been investigated. At annealing temperatures from 703 to 748 K, the single NC bcc(Si) phase is obtained in the crystallized alloys. The grain size and the Si-content in the NC bcc Fe(Si) phase for the alloys annealed at different temperatures are presented. The soft magnetic properties and the saturation magnetostriction for the alloys with the NC bcc Fe(Si) phase are also measured. The results show that, the saturation magnetizotion and the permeability are improved for the alloys with only the NC bcc Fe(Si) phase and become better with decreasing of the NC bcc phase size, and the saturation magnetostriction declines for the alloys with increasing Si-content in the NC bcc Fe(Si) phase.

关键词： Si Structure and Magnetic Properties of Fe B9Cu1 Alloy with Nanoscale Grain Size Cu

Influence of Magnetic Field Intensity on the Shape of the μ-T Curves for Fe73.5Cu1Nb3Si13.5B9 Alloy

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Journal of Materials Science & Technology 2002年第3期18卷 224-226页

作者： Yajing ZHANG, Kaiyuan HE, Zhi WANG, Changsheng LIU, lizhi cheng and Hongcai YANGSchool of Materials & Metallurgy, Northeastern University, Shenyang 110004, China [ Manuscript received December 6, 2000, in revised form March 30, 2001] Northeastern Univ Sch Mat & Met Shenyang 110004 Peoples R China

Under different magnetic field intensities, the dependence of the permeability μ on temperature T(μ-T curve) for the Fe7.3Cu1Nb3Si13.5B9 alloy annealed at 350-620℃ was investigated. The results showed that the magnetic field intensity had a remarkable influence on the shape of μ-T curves. For amorphous alloy, the sharp Hopkinson peak of μ-T curve disappeared gradually with the increase of magnetic field intensity.

关键词： Fe73.5Cu1Nb3Si13.5B9 Permeability Amorphous alloy

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基于小波域字典学习方法的图像双重稀疏表示

国防科技大学学报 2012年第4期34卷 126-131页

作者：梁锐华成礼智国防科技大学理学院湖南长沙410073

提出了一种有效地结构化字典生成算法以及图像双重稀疏表示方法。在Rubinstein等提出的图像双重稀疏表示模型的基础上,引入小波零树结构,将同一空间位置对应的同方向跨尺度小波基函数的线性组合作为新的基函数,并通过K-SVD学习算法得到... 详细信息

提出了一种有效地结构化字典生成算法以及图像双重稀疏表示方法。在Rubinstein等提出的图像双重稀疏表示模型的基础上,引入小波零树结构,将同一空间位置对应的同方向跨尺度小波基函数的线性组合作为新的基函数,并通过K-SVD学习算法得到线性组合系数,由此得到了一种更加切合图像方向特征的结构化字典学习算法。在此基础上提出了相应的图像分解与重构算法。遥感图像M项逼近实验以及压缩仿真实验表明,本文提出的结构化字典比已有的字典具有更好的图像稀疏表示效果。

关键词：稀疏表示字典学习小波零树图像压缩

Research and Comparison of CUDA GPU Programming in MATLAB and Mathematica

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Research and Comparison of CUDA GPU Programming in MATLAB an...

Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability

2013年中国智能自动化学术会议

作者： Xiongwei Liu lizhi cheng Qun Zhou Department of Mathematics and System Science College of ScienceNational University of Defense Technology School of Information Science and Engineering Hunan International Economics University

This paper discusses and analyzes the reasons of fast development of GPU computing,CUDA-enabled GPU programming model,direct matrix multiplication algorithms based on CPU and CUDA-enabled *** three different environments of VC++2008,Matlab 2009b and Mathematica 8,for matrices of different dimensions,we compare execution efficiency by means of *** research and study,GPU Computing in mathematica software systems provides a good choice because of their advantages of low cost,ease of use,high efficiency.

关键词： GPU CUDA Mathematica MATLAB Matrix multiplication

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Journal of Materials Science & Technology 2001年第2期17卷 260-262页

作者： Min XU, Mingxiu QUAN and Zhuangqi HU State Key Laboratory for RSA, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China lizhi cheng and Kaiyuan HE School of Materials and Metallurgy, Northeastern University, Shenyang 110004, Ch Chinese Acad Sci Inst Met Res State Key Lab RSA Shenyang 110016 Peoples R China Northeastern Univ Sch Met & Mat Shenyang 110004 Peoples R China

A ferromagnetic amorphous Fe73Al4Ge2Nb1P10C6B4 alloy with high glass-forming ability was synthesized by melt spinning. The supercooled liquid region before crystallization reaches about 65.7 K. The crystallized structure consists of alpha -Fe, Fe3B, FeB, Fe3P and Fe3C phases. The Fe-based amorphous alloy exhibits good magnetic properties with a high saturation magnetization and a low saturated magnetostriction. The crystallization leads to an obvious decrease in the soft magnetic properties.

关键词： Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability Am GFA