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Effects of Process Parameters of Semisolid Stirring on Microstructure of Mg–3Sn–1Mn–3SiC(wt%) Strip Processed by Rheo-rolling

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Acta Metallurgica Sinica(English Letters) 2017年第1期30卷 66-72页

作者： zhan-yong zhao Ren-Guo Guan Jian-Hong zhang Zhou-Yang zhao Pei-Kang Bai School of Materials Science and Engineering North University of China School of Materials Science and Engineering Northeastern University

A novel semisolid stirring and rheo-rolling process for preparing Mg-3Sn-1Mn-3SiC （wt%） composite strips was proposed, and the effects of process parameters of semisolid stirring on microstructures of Mg-3Sn-1Mn-3SiC （wt%） composite strips were investigated. The average grain size and roundness decrease, and the distribution of SiC becomes more homogeneous with the decrease in stirring temperature and the increase in the stirring speed. When the stirring time is increased, the distribution of SiC particles tends to be homogeneous, and the average grain diameter and roundness of α- Mg grain decrease. Under the following process parameters： the stirring temperature at 640 ℃, the stirring speed at 1100 rpm, the stirring time at 30 min and the roll speed at 0.2 m/s, Mg-3Sn-1Mn-3SiC （wt%） strip with a cross-sectional size of 4 mm × 160 mm was prepared. The ultimate tensile strength and elongation of Mg-3Sn-1Mn-3SiC （wt%） composite strip reached 226 ± 6 MPa and （7.4 ± 0.2）%, which are obviously improved in comparison with Mg-3Sn-1Mn （wt%）.

关键词： Mg-matrix composite Rheo-rolling Microstructure Property

Microstructure and properties of A2017 alloy strips processed by a novel process by combining semisolid rolling,deep rolling,and heat treatment

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 770-778页

作者： Ren-guo Guan Xiang Wang zhan-yong zhao Wei-wei Wang Fu-rong Cao Chun-ming Liu College of Materials and Metallurgy Northeastern University

A novel short process for producing A2017 alloy strips with notable features of near net shape, saving energy, low cost, and high product performance was developed by combining semisolid rolling, deep rolling, and heat treatment. The microstructure and properties of the A2017 alloy strips were investigated by metallographic microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, tensile testing, and hardness measurement. The cross-sectional microstructure of the A2017 alloy strips is mainly composed of near-spherical primary grains. Many eutectic phases CuA12 formed along primary grain boundaries during semisolid rolling are crushed and broken into small particles. After solution treatment at 495℃ for 2 h the eutectic phases at grain boundaries have almost dissolved into the matrix. When the solution treatment time exceeds 2 h, grain coarsening happens. More and more grain interior phases precipitate with the aging time prolonging to 8 h. The precipitated particles are very small and distribute homogenously, and the tensile strength reaches its peak value. When the aging time is prolonged to 12 h, there is no obvious variation in the amount of precipitated phases, but the size and spacing of precipitated phases increase. The tensile strength of the A2017 alloy strips produced by the present method can reach 362.78 MPa, which is higher than that of the strips in the national standard of China.

关键词： aluminum alloys semisolid rolling heat treatment microstructure mechanical properties

Model for Influences of Magnetic Fields on Intracellular Calcium Oscillations

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Communications in Theoretical Physics 2009年第7期52卷 168-172页

作者： zhanG Yu-Hong zhan yong zhao Tong-Jun CHEN Ya-Fei YUAN Chang-Qing School of Sciences Hebei University of Technology Tianjin 300130 China

Based on the model of the two calcium stores developed by Goldbeter, the influence of external magnetic field on the calcium concentration has been discussed. We believe that the cell membrane is a major site of interaction for extremely-low-frequency （ELF） electromagnetic fields, and the permeability of ions can be changed with the changing electromagnetic fields. It is shown that magnetic field initiates intraeellular calcium oscillation with a threshold in flux density, and that the calcium oscillations do not occur if the density of magnetic field is below the threshold. The results of theoretical calculation are consistent with that of the experiment. The intracellular free calcium concentrations of different cells exposed to the same magnetic fields are different from each other. It is indicated that the different behaviors such as oscillation, rise and invariability of calcium concentration are associated with the sort of cells.

关键词： calcium oscillation magnetic fields calcium concentration

Mathematic model of rolling pressure during a semisolid shearing-rolling process

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1121-1127页

作者： Ren-guo Guan zhan-yong zhao Chao Lian Qiu-sheng zhang Chun-ming Liu College of Materials and Metallurgy Northeastern UniversityShenyang 110819China

A mathematic model of rolling pressure during a novel semisolid shearing-rolling process was established. The rolling pressure in this process is higher than that in the conventional rolling. The increment of rolling pressure in the backward slip zone is higher than that in the forward slip zone, and the neutral plane moves toward to the roll gap entrance. The maximum and the average rolling pressures increase with the decrease of strip thickness, and the effects of strip thickness on the rolling pressure is more obvious in the forward slip zone than in the backward slip zone. Meanwhile, the neutral plane moves toward the roll gap exit with the decrease of strip thickness. The maximum and average rolling pressures increase with the decrease of strip width, and the strip width affects the pressure more obviously in the backward slip zone than in the forward slip zone. At the same time, the neutral plane moves toward the roll gap entrance with the decrease of strip width. The maximum and average rolling pressures increase with increasing roll radius, and the neutral plane moves toward the roll gap exit.

关键词： semisolid rolling pressure mathematic models strips magnesium alloys

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一种模块式自动化激光诱导击穿光谱测控系统

光电子．激光 2015年第8期26卷 1561-1567页

作者：杨诚詹永照常州信息职业技术学院江苏常州213164 江苏大学计算机科学与通信工程学院江苏镇江212013

为提高激光诱导击穿光谱（LIBS）仪对不同型号部件的兼容性,优化LIBS仪参数和测试流程,研制了一种模块式的自动化LIBS测控系统。实际测试表明,研制的测控系统可以兼容市场上大部分类型的LIBS部件,提升了LIBS仪对不同部件的兼容性及自身... 详细信息

为提高激光诱导击穿光谱（LIBS）仪对不同型号部件的兼容性,优化LIBS仪参数和测试流程,研制了一种模块式的自动化LIBS测控系统。实际测试表明,研制的测控系统可以兼容市场上大部分类型的LIBS部件,提升了LIBS仪对不同部件的兼容性及自身的灵活性,其中光谱仪、激光器等核心部件已测试兼容至少3种不同型号的部件。此外,设计多层迭代式自动化测试流程,提高了LIBS仪参数优化过程的效率。在延时时间的优化测试中,延时时间的优化范围为1.28-18.28μs,步进值分别为1.0、0.5、0.2和0.1μs时,与手动测试平台相比,测试效率分别提升了2.81、3.15、3.72和4.15倍。

关键词：激光器激光诱导击穿光谱(LIBS) 测控系统部件

具有噪声过滤功能的协同训练半监督主动学习算法

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模式识别与人工智能 2009年第5期22卷 750-755页

作者：詹永照陈亚必江苏大学计算机科学与通信工程学院镇江212013

针对基于半监督学习的分类器利用未标记样本训练会引入噪声而使得分类性能下降的情形,文中提出一种具有噪声过滤功能的协同训练半监督主动学习算法.该算法以3个模糊深隐马尔可夫模型进行协同半监督学习,在适当的时候主动引入一些人机交... 详细信息

针对基于半监督学习的分类器利用未标记样本训练会引入噪声而使得分类性能下降的情形,文中提出一种具有噪声过滤功能的协同训练半监督主动学习算法.该算法以3个模糊深隐马尔可夫模型进行协同半监督学习,在适当的时候主动引入一些人机交互来补充类别标记,避免判决类别不相同时的拒判和初始时判决一致即认为正确的误判情形.同时加入噪声过滤机制,用以过滤由机器自动标记的可能是噪声的样本.将该算法应用于人脸表情识别.实验结果表明,该算法能有效提高未标记样本的利用率并降低半监督学习而引入的噪声,提高表情识别的准确率.

关键词：表情识别协同训练半监督主动学习噪声过滤机制模糊深隐马尔科夫模型(FBMM)

Semi-supervised classification based on Markov Random Field and Robust Error Function

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通讯和计算机（中英文版） 2009年第4期6卷 1-5页

作者： LIN Qing SHAN Ping-ping WANG Shi-tong zhan yong-zhao Nanjing University of Science and Technology Nanjing 210094 China School of Computer Science and Telecommunication Engineering Jiangsu University Zhenjiang 212013 China School of Information Technology Jiangnan University Wuxi 214122 China

基于可分度和支持度的模糊密度赋值融合识别算法

维普期刊数据库评论

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模式识别与人工智能 2012年第2期25卷 346-351页

作者：詹永照张娟毛启容江苏大学计算机科学与通信工程学院镇江212013

模糊积分理论可有效处理分类决策不确定性问题.当前模糊密度的确定方法未考虑各个分类器识别结果的可区分程度及各分类器对识别结果的支持程度,会丢失融合识别的相关信息.文中提出基于可分度和支持度的自适应模糊密度赋值融合识别算法.... 详细信息

模糊积分理论可有效处理分类决策不确定性问题.当前模糊密度的确定方法未考虑各个分类器识别结果的可区分程度及各分类器对识别结果的支持程度,会丢失融合识别的相关信息.文中提出基于可分度和支持度的自适应模糊密度赋值融合识别算法.该算法根据各分类器对待识别样本的识别结果的可区分程度和支持程度对分类器的融合模糊密度进行自适应赋值,从而有效实现多分类器融合识别.将该算法应用于自然交互环境下的人脸表情识别和Cohn-Kanade表情识别.实验结果表明,该算法能有效提高总体表情识别率.

关键词：融合识别模糊密度可分度支持度人脸表情识别

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资本市场发展、军民融合与产业结构优化升级

南开经济研究 2016年第5期 36-54页

作者：湛泳赵纯凯湘潭大学商学院

军民融合是实现中国梦和强军梦的国家战略,对推动中国国防科技工业发展和产业结构升级有重要的意义。本文基于资本市场、军民融合和产业结构优化升级的理论模型,利用2007—2014年中国省际面板数据和两阶段系统GMM估计法,对所提出的假说... 详细信息

军民融合是实现中国梦和强军梦的国家战略,对推动中国国防科技工业发展和产业结构升级有重要的意义。本文基于资本市场、军民融合和产业结构优化升级的理论模型,利用2007—2014年中国省际面板数据和两阶段系统GMM估计法,对所提出的假说进行了实证检验。结果表明,银行中长期信贷市场对军民融合的正面影响最大,股票市场整体上对军民融合的促进作用不明显,但分别对"军转民"与"民参军"都存在显著的正效应,企业债券市场制约了军民融合的发展且对"民参军"的影响大于"军转民"。本文进一步发现,目前军民融合有利于第二产业发展,对第三产业影响不显著,对高技术产业存在挤出效应,股票市场和企业债券市场能通过军民融合这一路径来影响第二产业和高技术产业,但银行中长期信贷市场对产业结构优化升级的间接效应不明显。

关键词：资本市场军民融合产业结构优化升级