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Convergence of multi-block Bregman ADMM for nonconvex composite problems

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Science China(Information Sciences) 2018年第12期61卷 53-64页

作者： fenghui wang Wenfei CAO Zongben XU School of Mathematics and Statistics Xi'an Jiaotong University Department of Mathematics Luoyang Normal University School of Mathematics and Information Science Shaanxi Normal University

The alternating direction method with multipliers(ADMM) is one of the most powerful and successful methods for solving various composite problems. The convergence of the conventional ADMM(i.e.,2-block) for convex objective functions has been stated for a long time, and its convergence for nonconvex objective functions has, however, been established very recently. The multi-block ADMM, a natural extension of ADMM, is a widely used scheme and has also been found very useful in solving various nonconvex optimization problems. It is thus expected to establish the convergence of the multi-block ADMM under nonconvex frameworks. In this paper, we first justify the convergence of 3-block Bregman ADMM. We next extend these results to the N-block case(N≥3), which underlines the feasibility of multi-block ADMM applications in nonconvex settings. Finally, we present a simulation study and a real-world application to support the correctness of the obtained theoretical assertions.

关键词： nonconvex regularization alternating direction method subanalytic function K-L inequality Bregman distance

Effective Elastic Moduli of Ceramics with Pores

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Journal of Materials Science & Technology 1998年第3期14卷 286-288页

作者： wang, fenghui Gou, Wenxuan Zheng, Xiulin Lu, Minxu Northwestern Polytech Univ Dept Engn Mech Xian 710072 Peoples R China Northwestern Polytech Univ Dept Mat Sci & Engn Xian 710072 Peoples R China Xian Tubular Goods Res Ctr Xian 710061 Peoples R China

A contribution was given to the theoretical research on the stiffness of ceramic materials, under the approximation of the average stress field, the relation E equals E//0(1 minus p)/(1 plus 2.5p) was derived to describe the dependence of the modulus of elasticity on porosity. The prediction of this model is consistent with the experimental data from several ceramics such as reacting sintered Si//3N//4, MgO and MgAl//2O//3. (Edited author abstract) 12 Refs.

关键词： Ceramic materials

Effect of Notches and Environment on Cyclic Life of Alumina

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Journal of Materials Science & Technology 1995年第6期11卷 452-454页

作者： fenghui wang Minxu LU Jianfeng WE and Xiulin ZHENG (Northwestern Polytechnical University, Xi’an, 710072, China) Northwestern Ploytechnical Univ Xi'an China

Four-point bending cyclic fatigue testing has been performed for alumina specimens with two kinds of notch radius in corrosive environments. Cyclic life is found to be dependent on notch radius and environments, the tests also show that the fatigue notch factor Kf is roughly equal to the theoretical notch factor Kt, the fatigue strength and fatigue limit σc are reduced in environment in the sequence: formamide-room air-distilled water

关键词： Alumina

两种Al_2O_3结构陶瓷断裂强度的统计分析

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稀有金属材料与工程 2000年第5期29卷 311-314页

作者：王峰会鄢君辉王泓西北工业大学西安710072

研究了结构陶瓷材料的统计分布规律。首先通过实验测试了两种 Al2 O3陶瓷光滑试件和不同缺口半径试件的断裂强度 ;对实验数据用正态分布和 Weibull分布分别进行了分析 ,发现对于缺口件 ,用正态分布描述其断裂强度分散性要比 Weibull分... 详细信息

研究了结构陶瓷材料的统计分布规律。首先通过实验测试了两种 Al2 O3陶瓷光滑试件和不同缺口半径试件的断裂强度 ;对实验数据用正态分布和 Weibull分布分别进行了分析 ,发现对于缺口件 ,用正态分布描述其断裂强度分散性要比 Weibull分布好一些。这也说明在对陶瓷材料结构件进行设计时。

关键词：结构陶瓷断裂强度三氧化铝统计分析正态分布

FEM Analysis of Force Parameters During Hot Extrusion Expanding and Reducing Tube Process

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武汉理工大学学报 2006年第S2期28卷 737-740页

作者： wang fenghui JIAO Anyuan LI Haidong GAO Xingqi YANG Siqiong (Anshan University of Science & Technology,Anshan 114044,China Anshan University of Science & Technology Anshan 114044China

In this paper,based on the plastic forming large deformation theory and thermodynamic elastic-plastic FEM,the process of expanding and reducing tube was analyzed by using nonlinear finite element software *** coupled thermal-me- chanical models for the thermal-extrusion tube process were established,and the dynamic simulation to them was carried *** the study on 3 D deformation regulation of the thermal-extrusion tube,the distribution of stress,strain and the curves between the force of extrusion and the distance were *** a result,with only a small quantity of necessary experiments,the select of the schemes and parameters can conveniently be performed in the ***,not only large numbers of experiments can be avoided, but also trial-manufacture period is consumedly shortened and some costs may be *** addition,in order to validate our nu- merical calculation,an experiment of the tube made of 20 steel is presented in this *** agreement is shown between mea- sured and predicted results of the theoretical analysis *** study provides a scientific basis for parametric optimizations of the thermal extrusion expanding and reducing tube production *** the same time,the method used in the present paper has important referential value for studying the similar thermal extrusion parts.

关键词： finite element method thermodynamic couple numerical simulation

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脆性材料断裂韧性测试及表现断裂韧性的估算

稀有金属材料与工程 1999年第6期28卷 406-409页

作者：王峰会何泽夏西北工业大学西安710072

用2种测试技术测试了脆性材料的断裂韧性。一种是利用楔入法在悬臂梁试件预裂出自然裂纹；另一种是用研磨法在三点弯曲试件上作出微米级的尖缺口裂纹。分别测试了3种材料的断裂韧性，并用提出的模型分别评估了多晶和非晶脆性材料的断裂... 详细信息

用2种测试技术测试了脆性材料的断裂韧性。一种是利用楔入法在悬臂梁试件预裂出自然裂纹；另一种是用研磨法在三点弯曲试件上作出微米级的尖缺口裂纹。分别测试了3种材料的断裂韧性，并用提出的模型分别评估了多晶和非晶脆性材料的断裂韧性。

关键词：脆性材料断裂韧性测试评估

The Calculating System of Accident Vehicle Body Plastic Deformation Based on the Finite Element Method

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The Calculating System of Accident Vehicle Body Plastic Defo...