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火灾下轴心受压H型截面约束钢柱整体稳定设计

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土木建筑与环境工程 2009年第4期31卷 31-36页

作者：王培军李国强 wang yong-chang 山东大学土建与水利学院土木工程系济南250061 土木工程防灾国家重点试验室上海200092 同济大学土木工程学院建筑工程系上海200092 School of Mechanical Aerospace and Civil Engineering University of Manchester PO Box88 Manchester M60 1QD

利用验证的有限元模型分析了轴向约束刚度比、轴力荷载比和钢柱长细比对火灾下轴心受压H形截面约束钢柱屈曲温度和破坏温度的影响,给出了其屈曲温度和破坏温度的计算方法。轴向约束刚度比对约束钢柱屈曲温度和破坏温度的影响可用指数函... 详细信息

利用验证的有限元模型分析了轴向约束刚度比、轴力荷载比和钢柱长细比对火灾下轴心受压H形截面约束钢柱屈曲温度和破坏温度的影响,给出了其屈曲温度和破坏温度的计算方法。轴向约束刚度比对约束钢柱屈曲温度和破坏温度的影响可用指数函数表示,轴力荷载比和钢柱长细比对约束钢柱屈曲温度和破坏温度的影响可用多项式表示。采用有限元方法对计算公式进行了验证,设计公式计算结果与有限元分析结果吻合较好,且设计公式给出偏于安全的结果。

关键词：约束钢柱屈曲温度破坏温度设计方法抗火

外围介质介电常数对金纳米棒光学性质影响的数值模拟

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光谱学与光谱分析 2005年第6期25卷 916-919页

作者：朱键王永昌西安交通大学理学院陕西西安710049

采用电化学方法制备出悬浮胶体金纳米棒。在室温下测得其紫外可见吸收光谱和荧光发射光谱。结合准静电场理论与散射理论对金纳米棒的光学特性进行了数值模拟。计算结果表明,由于金纳米棒形状的各向异性,吸收截面与散射截面均出现两个... 详细信息

采用电化学方法制备出悬浮胶体金纳米棒。在室温下测得其紫外可见吸收光谱和荧光发射光谱。结合准静电场理论与散射理论对金纳米棒的光学特性进行了数值模拟。计算结果表明,由于金纳米棒形状的各向异性,吸收截面与散射截面均出现两个共振峰,分别对应于横截方向与长轴方向的表面等离子共振。对于几何形状一定的金纳米棒,在外围介质介电常数从1 5增加到2 5的过程中,两个共振吸收峰均增强并非线性红移。然而对于散射光谱,短波方向的共振峰线性红移,强度变化微弱;长波方向的共振峰减弱并非线性红移。

关键词：纳米棒吸收散射荧光介电常数

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金纳米颗粒的紫外、蓝紫光波段光致荧光特性

光谱学与光谱分析 2005年第2期25卷 235-238页

作者：朱键王永昌西安交通大学理学院陕西西安710049

采用电化学方法制备出粒径在20～30nm的悬浮胶体金纳米颗粒。研究了金纳米颗粒的荧光发射光谱特性。在377和459nm观察到两个荧光发射峰,分别位于紫外和蓝紫光波段,对应的敏感激发波长为220nm。减小激发光强度或降低金纳米颗粒的粒子数... 详细信息

采用电化学方法制备出粒径在20～30nm的悬浮胶体金纳米颗粒。研究了金纳米颗粒的荧光发射光谱特性。在377和459nm观察到两个荧光发射峰,分别位于紫外和蓝紫光波段,对应的敏感激发波长为220nm。减小激发光强度或降低金纳米颗粒的粒子数密度都会使377nm处的荧光发射峰强度减弱。位于459nm处的荧光发射峰对激发光强度和颗粒数密度变化更为敏感,并且在激发光强度降低到一定阈值或粒子数密度高于一定阈值后消失。随着激发光强度的增加,位于377和459nm处的两发射峰强度逐渐靠近,其比值逼近于1。实验结果与随机分布介质的自组织散射式谐振腔理论符合得较好。这表明胶体金纳米颗粒中存在循环多重散射,并由此引发了蓝光及紫外波段的荧光增强,这在光存储和全色显示等方面具有潜在的应用前景。

关键词：金纳米颗粒荧光发射对激发光波段荧光增强紫外光强度胶体金观察比值

膨胀型钢结构防火涂层耐湿热性能的理论分析与机理研究

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建筑材料学报 2012年第1期15卷 85-90页

作者：王玲玲李国强 wangyong-chang 同济大学土木工程学院上海200092 曼彻斯特大学土木力学与航空学院曼彻斯特M139PL

为考察膨胀型钢结构防火涂层的湿热老化机理及在湿热环境下防火涂层防火隔热性能随使用时间的变化规律,对隔热性能试验的试验结果进行了计算和总结,并通过傅里叶红外光谱检测和炭化层结构的扫描电镜对U型、A型这2种膨胀型钢结构防火涂... 详细信息

为考察膨胀型钢结构防火涂层的湿热老化机理及在湿热环境下防火涂层防火隔热性能随使用时间的变化规律,对隔热性能试验的试验结果进行了计算和总结,并通过傅里叶红外光谱检测和炭化层结构的扫描电镜对U型、A型这2种膨胀型钢结构防火涂料进行了湿热老化机理分析.结果表明:涂层发生老化是由于涂层内的亲水性物质向涂层表面迁移和析出;U型、A型这2种涂层的等效导热系数随老化时间延长总体上均呈现出增大的趋势,且增幅与涂料的基体树脂和阻燃体系的组分有关;经过42次湿热老化循环后,U型涂层等效导热系数增加了50%以上,A型涂层等效导热系数的增幅超过了100%,而厚度不同的A型涂层其等效导热系数的变化规律有所区别.

关键词：膨胀型钢结构防火涂层湿热老化隔热性能等效导热系数

The Hilbert expansion of the Boltzmann equation in the incompressible Euler level in a channel

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Science China Mathematics 2025年第1期68卷 39-88页

作者： Feimin Huang Weiqiang wang yong wang Feng Xiao Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and StatisticsHunan Normal University

The study of the hydrodynamic limit of the Boltzmann equation with physical boundary is a challenging problem due to the appearance of the viscous and Knudsen boundary *** this paper,the hydrodynamic limit from the Boltzmann equation with the specular reflection boundary condition to the incompressible Euler equations in a channel is *** on the multi-scaled Hilbert expansion,the equations with boundary conditions and compatibility conditions for interior solutions,and viscous and Knudsen boundary layers are derived under different scaling,***,some uniform estimates for the interior solutions,and viscous and Knudsen boundary layers are *** the help of the L2-L∞framework and the uniform estimates obtained above,the solutions to the Boltzmann equation are constructed by the truncated Hilbert expansion with multiscales,and hence the hydrodynamic limit in the incompressible Euler level is justified.

关键词： Boltzmann equation incompressible Euler equations hydrodynamic limit Hilbert expansion specular reflection boundary condition viscous boundary layer Knudsen boundary layer

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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Science China Chemistry 2025年第1期68卷 12-14页

作者： Wei-Lei Zhou Siwei wang yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

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Excess Loss of the Coupling System to Double-Function Optical Circulators Utilizing Lens Twice and Two-Fiber Tips

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The Journal of China Universities of Posts and Telecommunications 2005年第3期12卷 49-53页

作者： TIAN Yan-ning FANG Qiang wang yong-chang SUN Ai-jing BAI Ju-rong YANG Yi-fei Xi'an Jiaotong University Xi'an 710049 P.R. China Xi'an Institute of Posts and Telecommunications Xi'an 710061 P.R. China 不详

A new type of double function optical circulator for double fibers is proposed in this paper. Two fiber tips and lens twice are employed in this kind of device as the coupling system for what is believed to be the first time. Because two fiber tips and lens twice are used, the function of optical circulator is duplicated in comparison with conventional optical circulator with single fiber tip. Thus the optical circulator has a low cost and a small volume comparatively. Excess loss of the coupling system and the misalignment of the lens twice in angular error and the position error to the developed circulator are analyzed and discussed by using Gauss wave and double integral in theory. The analysis results show that the excess loss is zero when each distance is equal to f between every adjacent： fraction and without misalignment error in the coupling system. In addition, the excess loss is increasing with increment of the distance error and the angular error. The errors of the angular of the optical axis to lens and the distance between the SL to lens are the main source of the excess loss. The higher the errors are, the higher the excess loss is. It＇s very important for reducing the misalignment errors in the coupling system with high ratio of coupling to achieve low excess loss. Details of design and excess loss in the coupling system of this circulator are presented.

关键词： optical circulator double fiber tips lens twice double Integral excess loss

Industrial Control Anomaly Detection Based on Distributed Linear Deep Learning

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Computers, Materials & Continua 2025年第1期82卷 1129-1150页

作者： Shijie Tang yong Ding Huiyong wang School of Computer Science and Information Security Guilin University of Electronic TechnologyGuilin541004China School of Electronic Engineering and Automation Guilin University of Electronic TechnologyGuilin541004China Guangxi Engineering Research Center of Industrial Internet Security and Blockchain Guilin University of Electronic TechnologyGuilin541004China Institute of Cyberspace Technology HKCT Institute for Higher EducationHong Kong999077China School of Mathematics&Computing Science Guilin University of Electronic TechnologyGuilin541004China

As more and more devices in Cyber-Physical Systems(CPS)are connected to the Internet,physical components such as programmable logic controller(PLC),sensors,and actuators are facing greater risks of network attacks,and fast and accurate attack detection techniques are *** key problem in distinguishing between normal and abnormal sequences is to model sequential changes in a large and diverse field of time *** address this issue,we propose an anomaly detection method based on distributed deep *** method uses a bilateral filtering algorithm for sequential sequences to remove noise in the time series,which can maintain the edge of discrete *** use a distributed linear deep learning model to establish a sequential prediction model and adjust the threshold for anomaly detection based on the prediction error of the validation *** method can not only detect abnormal attacks but also locate the sensors that cause *** conducted experiments on the Secure Water Treatment(SWAT)and Water Distribution(WADI)public *** experimental results show that our method is superior to the baseline method in identifying the types of attacks and detecting efficiency.

关键词： Anomaly detection CPS deep learning MLP(multi-layer perceptron)

Massive MIMO网络中低复杂度的MMSE检测方法

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北京邮电大学学报 2016年第6期39卷 57-61页

作者：汪彬常永宇权威张戬北京邮电大学信息与通信工程学院北京100876 华为技术有限公司北京研究所北京100085

设计出大规模多入多出(massive MIMO)网络中一种有效、低复杂度的最小均方误差(MMSE)接收机结构.该接收机基于最陡下降和最小均方算法,能够避免大规模矩阵求逆运算.数学推导结果证明,这2种算法应用于MMSE检测时是收敛的.此外,分析了影... 详细信息

设计出大规模多入多出(massive MIMO)网络中一种有效、低复杂度的最小均方误差(MMSE)接收机结构.该接收机基于最陡下降和最小均方算法,能够避免大规模矩阵求逆运算.数学推导结果证明,这2种算法应用于MMSE检测时是收敛的.此外,分析了影响收敛速度的因素.仿真结果表明,应用于Massive MIMO网络中时该接收机收敛速度较快,切实可行.

关键词：大规模多入多出最小均方误差最陡下降最小均方