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Joint Active and Passive Beamforming Design for Hybrid RIS-Aided Integrated Sensing and Communication

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China Communications 2024年第10期21卷 101-112页

作者： Chu Hongyun yang mengyao Pan Xue Xiao Ge School of Communications and Information Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China

Integrated sensing and communication(ISAC) is considered an effective technique to solve spectrum congestion in the future. In this paper, we consider a hybrid reconfigurable intelligent surface(RIS)-assisted downlink ISAC system that simultaneously serves multiple single-antenna communication users and senses multiple targets. Hybrid RIS differs from fully passive RIS in that it is composed of both active and passive elements, with the active elements having the effect of amplifying the signal in addition to phase-shifting. We maximize the achievable sum rate of communication users by collaboratively improving the beamforming matrix at the dual function base station(DFBS) and the phase-shifting matrix of the hybrid RIS, subject to the transmit power constraint at the DFBS, the signal-to-interference-plus-noise-ratio(SINR) constraint of the radar echo signal and the RIS constraint are satisfied at the same time. The builtin RIS-assisted ISAC design problem model is significantly non-convex due to the fractional objective function of this optimization problem and the coupling of the optimization variables in the objective function and constraints. As a result, we provide an effective alternating optimization approach based on fractional programming(FP) with block coordinate descent(BCD)to solve the optimization variables. Results from simulations show that the hybrid RIS-assisted ISAC system outperforms the other benchmark solutions.

关键词： alternating optimization fractional programming hybrid reconfigurable intelligent surface integrated sensing and communication joint active and passive beamforming

Effect of Mg/Al Ratios on Hydration Mechanism of Tabular Alumina Carbon Composites Reinforced by Al4C3 in situ Reaction

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 800-805页

作者：杨依帆 JIANG Mingxue yang Ding'ao YUAN Shouqian ZHAO Jizeng ZHAO Wei yang mengyao College of Materials and Mineral Resources Xi'an University of Architecture and TechnologyXi'an 710055China Beijing Lier High-Temperature Materials Co. LtdBeijing 102211China Fuzhou University Zhicheng College Fuzhou 350002China

Hydration mechanism of tabular alumina carbon composites reinforced by Al4C3 in situ reaction with Mg and Al was researched in water steam using super automatic thermostatic water bath from 25 ℃ to 85 ℃. It is shown that hydration mechanism of the composites is chemical reaction control at 44.3 ℃-84 ℃ in H2O（g）. The hydration was controlled by diffusion from 24.7 ℃ to 33 ℃. The ratio of added Mg/Al influences the HMOR of the *** mechanism of HMOR of the composites with different ratios of Mg/Al can be discovered by means of SEM analysis. The active Mg/Al powder and flake graphite inside give the composites outstanding hot strength resulting from the interlocking structure of Al4C3 crystals at high temperature. Besides, the matrix changes into the Al4C3 with high refractoriness. The method of preventing the hydration of tabular alumina carbon composites reinforced by Al4C3 in situ reaction was immersed in the wax at suitable temperature or storing them below 33 ℃ in a dry place or storing them with paraffin-coating.

关键词： hydration mechanism tabular alumina carbon Al4C3 Mg/Al ratios

Kinetics and Mechanism of Oxidation Induced Contraction of MgAl2O4 Spinel Carbon Composites Reinforced by Al4C3 in situ Reaction

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Journal of Wuhan University of Technology(Materials Science) 2020年第4期35卷 778-785页

作者： yang mengyao XIAO Guoqing yang Ding'ao YUAN Shouqian ZAO Jizeng ZHAO Wei GAO Song ollege of Materials Science and Engineering Xi'an University of Architecture and TechnologyXi'an 710055China Beijing LierHigh-Temperature Materials Co. Ltd.Beijing 102211China Luoyang Lier Refractories Co. Ltd.Luoyang 471023China

Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25℃to 1400℃.It is shown that oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced Al4C3 in situ reaction is the common logarithm of oxidation time t and the oxygen partial pressure P inside MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction in air at 1400℃is as follows:P=F(-2.75×10^-4A+2.13×10^-3)*** nonsteady diffusion kinetic equation of O2 at 1400℃inside the composites is as follows:J=De *** of the total diffusional?flux of oxygen inside the composites at 1400℃is in inverse proportion to the oxidation *** nonsteady state effective diffusion coefficient De of O2(g)inside the composites decreases in direct proportional to the increase of the amount of metallic *** method of preventing the oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction is to increase the amount of *** slag erosion index of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 0.47 times that of MgO-CaO brick used in the lining above slag line area of a VOD stainless steel-making *** of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 26.7 MPa,HMOR of the composite is 3.6 times the same as that of MgO-CaO brick used in the lining above slag line area of a VOD *** service life is two times as many as that of MgO-CaO brick.

关键词： kinetics mechanism oxidation contraction MgAl2O4 spinel carbon Al4C3 in situ reaction

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多通道置信度加权颜色恒常性算法

光学学报 2021年第11期41卷 234-244页

作者：杨泽鹏解凯李桐杨梦瑶杨斌北京印刷学院信息工程学院北京102600

颜色恒常性是实现识别、分割和三维物体重建等视觉任务的重要前提。为使计算机视觉系统具有颜色恒常性感知功能,提出多通道特征置信度加权网络,在减少网络层数和模型参数的同时充分提取图像中的特征;通过多通道置信度加权方法利用每个... 详细信息

颜色恒常性是实现识别、分割和三维物体重建等视觉任务的重要前提。为使计算机视觉系统具有颜色恒常性感知功能,提出多通道特征置信度加权网络,在减少网络层数和模型参数的同时充分提取图像中的特征;通过多通道置信度加权方法利用每个通道中可以为光源估计提供更多信息的特征准确估计出全局场景光源。在基于重处理的ColorChecker和NUS-8数据集上的实验结果表明,本文算法通过对特征从多通道进行置信度加权,在各项评价指标上均优于目前的颜色恒常性算法,提高了算法的精确性和稳健性,可应用于需要进行色彩校正的计算机视觉任务。

关键词：视觉光学颜色恒常性光源估计多通道置信度加权轻量级网络

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei Xiao Qianqian Gu Haoyu Li mengyao Li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor extends the cycling life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Internal electric field Cationic accelerator Ion diffusion kinetics Cathode modification strategy Aqueous zinc ion battery

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基于局部特征提取的有监督的流形学习方法

机械工程学报 2017年第24期53卷 211-220页

作者：黎敏杨孟瑶陈泽赵启东北京科技大学机械工程学院北京100083 北京科技大学钢铁共性技术协同创新中心北京100083

为了提高工业产品的质量,提出一种基于局部特征提取的有监督的流形学习方法,用于工业生产过程中工艺参数的调整和优化。利用"多类邻域搜索"策略对每个样本点寻找邻域矩阵,对邻域矩阵进行特征分解,获得每个样本点的演化矢量,进而可以求... 详细信息

为了提高工业产品的质量,提出一种基于局部特征提取的有监督的流形学习方法,用于工业生产过程中工艺参数的调整和优化。利用"多类邻域搜索"策略对每个样本点寻找邻域矩阵,对邻域矩阵进行特征分解,获得每个样本点的演化矢量,进而可以求得潜含在数据内部的主流形。另一方面,利用训练样本建立基于支持矢量数据描述的监控模型,对工艺过程进行监控。当发现异常样本时,将异常样本在主流形方向上进行投影,可以得到各个工艺参数的调整量,由此可将异常样本调控回到生产受控状态。利用IF钢实际生产过程数据进行验证,结果表明:新方法能有效提取出数据内部的流形结构,并通过主流形实现对工艺参数的调整,为实际生产过程提供了一种新的工艺参数优化方法。

关键词：有监督流形学习局部特征提取产品质量建模工艺参数优化

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基于函数型数据分析的半导体生产过程监控

机械工程学报 2018年第16期54卷 62-69页

作者：黎敏谢玄陈泽杨孟瑶杨德斌蒋靖北京科技大学钢铁共性技术协同创新中心北京科技大学机械工程学院北京中油瑞飞信息技术有限责任公司

提出一种基于函数型数据分析的非平稳生产状态下的多批次生产过程监控方法。引入函数型数据分析方法将三维数据中的每个变量沿时间方向进行函数拟合,从而将三维离散数据矩阵转化为二维函数矩阵。对各个变量曲线求取二阶导数,消除非平稳... 详细信息

提出一种基于函数型数据分析的非平稳生产状态下的多批次生产过程监控方法。引入函数型数据分析方法将三维数据中的每个变量沿时间方向进行函数拟合,从而将三维离散数据矩阵转化为二维函数矩阵。对各个变量曲线求取二阶导数,消除非平稳生产状态所导致的均值波动现象,增加建模的准确性。在此基础上,利用函数型主成分分析方法对各个变量的导数曲线进行特征提取,并使用基于权重的主成分融合方法,获得函数型主成分矩阵。利用支持向量数据描述方法对函数型主成分矩阵进行监控,并将其应用于工业半导体生产过程的监控中。结果表明,基于函数型数据分析的监控方法与传统方法相比,具有更低的漏检率,验证了新方法的有效性。

关键词：函数型数据分析函数型主成分分析过程监控非平稳生产过程

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斑秃相关免疫机制研究进展

中国麻风皮肤病杂志 2023年第6期39卷 446-450页

作者：杨梦瑶耿龙中国医科大学附属第一医院沈阳110000

斑秃是一种以非瘢痕性脱发为特征的自身免疫性皮肤病,其具体病因未明,可能与环境、遗传、免疫等有关。目前普遍认为生长期毛囊“免疫豁免的丧失”在斑秃的发病中起关键作用。近年来斑秃与其他自身免疫病的共同免疫学特性相继被发现,多... 详细信息

斑秃是一种以非瘢痕性脱发为特征的自身免疫性皮肤病,其具体病因未明,可能与环境、遗传、免疫等有关。目前普遍认为生长期毛囊“免疫豁免的丧失”在斑秃的发病中起关键作用。近年来斑秃与其他自身免疫病的共同免疫学特性相继被发现,多种新型生物制剂也逐渐被尝试应用于重度斑秃及传统方法疗效不佳者。本文对斑秃相关免疫机制的研究进展进行综述。

关键词：斑秃免疫通路细胞因子

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公务员职业承诺及形成过程研究

科研管理 2021年第6期42卷 194-201页

作者：王颖杨梦遥王笑宇北京师范大学政府管理学院北京100875

应用投资模型对在职公务员的职业承诺现状及产生过程进行探究,并基于角色扮演理论和社会交换理论,引入领导-成员交换关系作为调节变量,探讨其在职业承诺形成过程中的调节作用。使用462个有效样本进行的多项统计分析的结果表明:投资模型... 详细信息

应用投资模型对在职公务员的职业承诺现状及产生过程进行探究,并基于角色扮演理论和社会交换理论,引入领导-成员交换关系作为调节变量,探讨其在职业承诺形成过程中的调节作用。使用462个有效样本进行的多项统计分析的结果表明:投资模型理论能够很好地解释公务员的职业承诺及其产生过程,其中,职业满意度与职业投入对职业承诺有显著的正向影响;外在职业机会感知对职业承诺有显著的负向影响;领导-成员交换关系在职业投入对职业承诺的影响关系中有显著的调节作用,与领导存在"高质量"交换关系的个体的职业投入对职业承诺的影响高于"低质量"交换关系的个体。

关键词：公务员职业承诺投资模型领导-成员交换关系