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A level set method for reliability-based topology optimization of compliant mechanisms

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Science China(Technological Sciences) 2008年第4期51卷 443-455页

作者： zhang xianmin ouyang gaofei School of Mechanical Engineering South China University of TechnologyGuangzhou 510640China

Based on the level set model and the reliability theory, a numerical approach of reliability-based topology optimization for compliant mechanisms with multiple inputs and outputs is presented. A multi-objective topology optimal model of compliant mechanisms considering uncertainties of the loads, material properties, and member geometries is developed. The reliability analysis and topology optimization are integrated in the optimal iterative process. The reliabilities of the compliant mechanisms are evaluated by using the first order reliability method. Meanwhile, the problem of structural topology optimization is solved by the level set method which is flexible in handling complex topological changes and concise in describing the boundary shape of the mechanism. Numerical examples show the importance of considering the stochastic nature of the compliant mechanisms in the topology optimization process.

关键词： compliant mechanism reliability analysis topology optimization level set method

CaO-SiO_(2)-Al_(2)O_(3)-MgO-FeO渣对Al_(2)O_(3)的溶解

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钢铁 2024年第2期59卷 65-74页

作者：齐詹成日金武献民霍立桥朱俊涛刘成松张华倪红卫武汉科技大学省部共建耐火材料与冶金国家重点实验室湖北武汉430081 武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室湖北武汉430081 德龙钢铁有限公司炼钢厂河北邢台054009

为了控制低碳铝镇静钢中Al_(2)O_(3)夹杂物,并提升渣系对Al_(2)O_(3)夹杂物吸附能力,采用FactSage 8.1模拟计算CaO-SiO_(2)-Al_(2)O_(3)-5%MgO-5%FeO渣系的等黏度图和等ΔC/η(ΔC=C_(Al_(2)O_(3))^(s)-C_(Al_(2)O_(3))^(b),η为渣的黏度)值线图。根据模拟计算图选取合适的五元精炼渣做Al_(2)O_(3)的吸附试验,试验研究了Al_(2)O_(3)在CaO-SiO_(2)-Al_(2)O_(3)-5%MgO-5%FeO渣系中的溶解速率,讨论了Al_(2)O_(3)棒浸入深度、直径、转速、渣成分以及温度对Al_(2)O_(3)溶解速率的影响,求解了Al_(2)O_(3)在溶解过程中的活化能。最后,采用场发射扫描电子显微镜(Apreo S HiVac)对氧化铝棒与熔渣接触的界面处进行微区线元素的定性分析。研究结果表明,Al_(2)O_(3)在渣中的溶解速率受诸多因素的影响;溶解速率随氧化铝棒的旋转速度、棒直径、浸入深度和温度的增加而增加;溶解速率也会随着CaO含量的增加而增加,Al_(2)O_(3)和SiO_(2)含量的增加而降低。溶解速率高度依赖于熔渣的黏度,渣的黏度对Al_(2)O_(3)的溶解速率呈负相关,Al_(2)O_(3)的溶解速率与浓度驱动力呈正相关。氧化铝棒溶解于渣系前,会先生成中间相CaO·2Al_(2)O_(3)和CaO·6Al_(2)O_(3),中间相溶解在熔渣中,溶解于渣A中的表观活化能为410.9 kJ/mol。结合溶解速率图与等ΔC/η值线图进行对比,验证了Al_(2)O_(3)在渣中的溶解速率受渣物性的影响。

关键词：低碳铝镇静钢含FeO精炼渣 Al_(2)O_(3)夹杂物等黏度线溶解速率

Authenticated Quantum Dialogue Without Information Leakage

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Chinese Journal of Electronics 2018年第2期27卷 270-275页

作者： wang He zhang Yuqing WU gaofei MA hua The State Key Laboratory of Integrated Services Networks Xidian University National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences School of Mathematics and Statistics Xidian University

A lot of authenticated quantum dialogue protocols are springing up. Many of them have the problem of information leakage, or suffer from Man-In-TheMiddle attack. Some protocols can guarantee security, but have relatively low efficiency. Based on the above situation, we present a novel authenticated quantum dialogue protocol by using Bell states and entanglement *** this protocol, we adopt Einstein-Podolsky-Rosen(EPR)pairs to detect eavesdropping and transmit secret messages. We employ polarized photons to achieve authentication of users’ identity information. Compared with other quantum dialogue schemes with authentication, our protocol has several advantages. The transmitted particles are passed once and do not carry any secret messages. The proposed protocol can overcome the drawback of information leakage and resist against typical attacks. The efficiency is acceptable.

关键词： Quantum dialogue Bell states Authentication Entanglement swapping

Black-Box and Public Traceability in Multi-authority Attribute Based Encryption

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Chinese Journal of Electronics 2020年第1期29卷 106-113页

作者： ZHAO Qianqian WU gaofei MA hua zhang Yuqing wang He School of Cyber Engineering Xidian University School of Mathematics and Statistics Xidian University National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences

Ciphertext-policy Attribute-based encryption(CP-ABE) is a promising tool for implementing finegrained cryptographic access control. While the uniqueness of generating private keys brings extra security *** key escrow is inherent in CP-ABE systems because the trusted authority has the power to decrypt every ciphertext. The private keys are only associated with the attributes nor the user’s identity. Some malicious users might be tempted to leak their decryption privileges for financial gain without the risk of being caught as the decryption privilege could be shared by multiple users who own the same set of attributes. We propose a new multiauthority CP-ABE with blackbox and public traceability,where the private keys are assigned by the cooperation between one central authority and multi-authorities. The performance and security analyses indicate that the proposed scheme is highly efficient and provably secure under the security model.

关键词： CP-ABE Multi-authority User accountability

Multi-omics analyses of 398 foxtail millet accessions reveal genomic regions associated with domestication,metabolite traits,and antiinflammatory effects

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Molecular Plant 2022年第8期15卷 1367-1383页

作者： Xukai Li Jianhua Gao Jingyi Song Kai Guo Siyu Hou Xingchun wang Qiang He Yanyan zhang Yakun zhang Yulu Yang Jiaoyan Tang Hailang wang Staffan Persson Mingquan huang Lishuai Xu Linlin Zhong Dongqin Li Yongming Liu hua Wu xianmin Diao Peng Chen Xiaowen wang Yuanhuai Han Shanxi Key Laboratory of Minor Crop Germplasm Innovation and Molecular Breeding College of Life SciencesShanxi Agricultural UniversityTaiguChina Key Laboratory of Brewing Molecular Engineering of China Light Industry Beijing Technology and Business UniversityBeijingChina Department of Neurology University of MichiganAnn ArborMIUSA Shanxi Key Laboratory of Minor Crop Germplasm Innovation and Molecular Breeding College of AgricultureShanxi Agricultural UniversityTaiguChina Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijingChina Colllege of Plant Science and Technology Huazhong Agricultural UniversityWuhanChina Copenhagen Plant Science Centre Department of Plant&Environmental SciencesUniversity of CopenhagenFrederiksberg CDenmark Joint International Research Laboratory of Metabolic and Developmental Sciences School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityMinhangShanghai 200240China College of Resources and Environment Shanxi Agricultural UniversityTaiguChina College of Horticulture and Forestry Sciences Huazhong Agricultural UniversityWuhanChina National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhanChina Grandomics Biosciences Company Limited BeijingChina College of Food Science and Engineering Shanxi Agricultural UniversityTaiguChina

Foxtail millet(Setaria italica),which was domesticatedfromthewild speciesgreenfoxtail(Setaria viridis),isa richsource of phytonutrientsfor *** evaluate how breeding changed themetabolome offoxtail millet grains,we generated and analyzed the datasets encompassing the genomes,transcriptomes,metabolomes,and anti-inflammatory indices from 398 foxtail millet *** identified hundreds of common variants that influence numerous secondary *** observed tremendous differences in natural variations of the metabolites and their underlying genetic architectures between distinct sub-groups of foxtail ***,we found that the selection of the gene alleles associated with yellow grains led to altered profiles of metabolites such as carotenoids and endogenous *** CRiSPR-mediated genome editing wevalidated the function of PHYTOENE SYNTHASE1(PSY1)gene in affecting milletgrain colorand ***,our in vitro cell inflammation assays showed that 83 metabolites in millet grains have anti-inflammatory *** together,ourmulti-omics study illustrates how the breeding history of foxtail millet has shaped its metabolite *** datasets we generated in this study also provide important resources for further understanding how millet grain quality is affected by different metabolites,laying the foundations for future millet genetic research and metabolome-assisted improvement.

关键词： foxtail millet multi-omics,genetic association metabolome transcriptome anti-inflammatory effects

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平面三自由度微动工作台的输入耦合分析

中国机械工程 2005年第5期16卷 377-380页

作者：王华张宪民欧阳高飞汕头大学汕头515063 华南理工大学广州510641

　　基于线性分析理论,建立了柔性铰链式平面三自由度精密定位平台的分析模型;提出了一种计算该类工作台输入耦合的线性求解方法,该方法具有求解简便和计算量小等优点;针对微动工作平台的特点建立了有限元分析模型,通过有限元仿真,验证... 详细信息

　　基于线性分析理论,建立了柔性铰链式平面三自由度精密定位平台的分析模型;提出了一种计算该类工作台输入耦合的线性求解方法,该方法具有求解简便和计算量小等优点;针对微动工作平台的特点建立了有限元分析模型,通过有限元仿真,验证了线性法的正确性;讨论了有关参数对工作台输入耦合的影响程度,给出了对输入耦合有较大影响的设计参数。研究结果对设计低耦合输入微动工作平台具有指导意义。

关键词：柔性铰链微动工作台输入耦合有限元

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基于水平集方法的结构可靠性拓扑优化

机械工程学报 2008年第10期44卷 60-65页

作者：欧阳高飞张宪民华南理工大学机械工程学院广州510640

基于水平集方法,建立以水平集函数为优化变量、结构柔度极小化为目标、具有可靠性约束的结构拓扑优化模型,并提出一种基于可靠性的结构拓扑优化算法。首先,采用计算效率高的一次二阶矩法进行可靠性分析,编制计算可靠性指标的最优化方法... 详细信息

基于水平集方法,建立以水平集函数为优化变量、结构柔度极小化为目标、具有可靠性约束的结构拓扑优化模型,并提出一种基于可靠性的结构拓扑优化算法。首先,采用计算效率高的一次二阶矩法进行可靠性分析,编制计算可靠性指标的最优化方法。然后,根据结构可靠性指标的几何意义,优化求解符合可靠性约束的随机变量。将修正后的随机变量作为确定性变量进行结构拓扑优化设计,使基于可靠性的结构拓扑优化模型转为常规的结构拓扑优化模型,采用稳定、高效的水平集方法进行结构拓扑优化。最后以悬臂梁结构的可靠性拓扑优化为例,说明文中所提算法的简便性与有效性。

关键词：可靠性分析拓扑优化水平集方法

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结构拓扑优化中水平集方法的快速初始化研究

应用基础与工程科学学报 2008年第1期16卷 136-143页

作者：欧阳高飞张宪民华南理工大学机械工程学院广东广州510640

水平集方法是求解结构拓扑优化问题中的一种有效方法,该方法主要缺陷是每隔一定时间需要重新初始化水平集函数.因此,本文提出了一种基于偏微分方程和快速步进法的初始化算法.所提出的算法能够区分任意形状的闭合曲线或曲面的内外部,改... 详细信息

水平集方法是求解结构拓扑优化问题中的一种有效方法,该方法主要缺陷是每隔一定时间需要重新初始化水平集函数.因此,本文提出了一种基于偏微分方程和快速步进法的初始化算法.所提出的算法能够区分任意形状的闭合曲线或曲面的内外部,改进了以往初始化算法的数值不稳定缺陷,从而使水平集方法的计算效率和稳定性有了显著的提高.最后,通过算例验证了该算法的有效性.

关键词：结构拓扑优化水平集方法初始化

整体式空间3自由度精密定位平台的优化设计与试验

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机械工程学报 2007年第3期43卷 66-71页

作者：王华张宪民华南理工大学机械工程学院广州510640

根据柔顺薄板的弹性变形原理,设计一种整体式空间三自由度柔顺并联微动平台。分析该平台的输入耦合特性,对三种输入耦合形式对定位精度的影响进行讨论。基于有限元法,给出平台的刚度模型,对平台的结构尺寸进行优化设计,并通过ANSYS仿真... 详细信息

根据柔顺薄板的弹性变形原理,设计一种整体式空间三自由度柔顺并联微动平台。分析该平台的输入耦合特性,对三种输入耦合形式对定位精度的影响进行讨论。基于有限元法,给出平台的刚度模型,对平台的结构尺寸进行优化设计,并通过ANSYS仿真分析验证优化结果的正确性。在此基础上进一步建立平台的位置正解和位置逆解方程,对平台的定位精度进行试验研究,提出一种基于理论分析模型的试验修正方法,该方法能有效提高平台的定位精度,研究表明该平台具有亚微米级的定位精度。

关键词：定位平台输入耦合优化设计位置正解