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Performance analysis of quantum key distribution using polarized coherent-states in free-space channel

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Chinese Physics B 2023年第3期32卷 111-119页

作者：郑增特陈子扬黄露雨王翔宇喻松 State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronicsand Center for Quantum Information TechnologyPeking UniversityBeijing 100871China

In free space channel,continuous-variable quantum key distribution(CV-QKD)using polarized coherent-states can not only make the signal state more stable and less susceptible to interference based on the polarization non-sensitive of the free-space channel,but also reduce the noise introduced by phase ***,arbitrary continuous modulation can not be carried out in the past polarization coding,resulting in that the signal state can not obtain arbitrary continuous value in Poincare space,and the security analysis of CV-QKD using polarized coherent-states in free space is not *** we propose a new modulation method to extend the modulation range of signal states with an optical-fiber-based polarization *** particular,in terms of the main influence factors in the free-space channel,we utilize the beam extinction and elliptical model when considering the transmittance and adopt the formulation of secret key *** addition,the performance of the proposed scheme under foggy weather is also taken into consideration to reveal the influence of severe *** simulation shows that the proposed scheme is seriously affected by attenuation under foggy *** protocol fails when visibility is less than 1 *** the same time,the wavelength can affect the performance of the proposed ***,under foggy weather,the longer the wavelength,the smaller the attenuation coefficient,and the better the transmission *** proposed scheme can expand the modulation range of signal state,and supplement the security research of the scheme in the free-space channel,thus can provide theoretical support for subsequent experiments.

关键词： polarized coherent-states free-space channel performance analysis

湍流模型源项的数值处理方法对计算结果的影响研究

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空气动力学学报 2014年第6期32卷 868-873页

作者：王翔宇李栋西北工业大学翼型叶栅空气动力学国防科技重点实验室陕西西安710072

涡粘性湍流模型广泛应用于各种工程湍流问题的计算。对于大多数湍流模型,在湍流控制方程的右端会出现源项,其刚性给数值计算带来很大的影响。从源项的物理意义出发分析了源项导致求解困难的原因,并在通用的求解湍流模型方程的点隐法基础... 详细信息

涡粘性湍流模型广泛应用于各种工程湍流问题的计算。对于大多数湍流模型,在湍流控制方程的右端会出现源项,其刚性给数值计算带来很大的影响。从源项的物理意义出发分析了源项导致求解困难的原因,并在通用的求解湍流模型方程的点隐法基础上,以源项弱刚性的S-A湍流模型和源项强刚性的k-ωSST湍流模型为例,论述了生成项和耗散项之间的平衡关系对数值模拟的重要意义,给出了针对不同源项的具体处理方法。对RAE2882翼型跨声速流动算例的模拟结果表明,这些处理方法有效的提高了控制方程组的计算稳定性。

关键词： NS 方程源项刚性 S-A 湍流模型 k-ω SST 数值模拟

Preparation and Catalytic Properties of Ti-SBA-15 Mesoporous Materials

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Materials Sciences and Applications 2011年第6期2卷 661-668页

作者： Wenhao Ye Zheng Lin Beibei Dong Jinfeng Kang Xiucheng Zheng xiangyu wang 不详

Ti-SBA-15 mesoporous materials were directly synthesized via a hydrothermal process and characterized by using nitrogen adsorption-desorption measurements, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, diffuse reflectance ultraviolet-visible spectroscopy, and infrared ray spectroscopy. The effect of synthesis temperatures on the structure and catalytic efficiency in epoxidation of cyclohexene was discussed in details. The results showed that the optimal temperature was 100oC under the reaction conditions.

关键词： Ti-SBA-15 Hydrothermal Synthesis Synthesis Temperatures Cyclohexene Epoxidation

Nonsingular Terminal Sliding Mode Control for PMSM Servo System Based on Backlash Compensation and High-order Sliding Mode Observer

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Nonsingular Terminal Sliding Mode Control for PMSM Servo Sys...

第32届中国控制与决策会议

作者： Jianwei Gui Lu Zhang Shihua Li xiangyu wang School of Automation Southeast University Key Laboratory of Measurement and Control of Complex Systems of Engineering Ministry of Education

In this paper,the permanent magnet synchronous motor（PMSM） servo system with backlash is *** the mechanical transmission of the servo system uses gears,screw rods,on the one hand,the proper backlash can ensure the normal operation of the transmission mechanism;on the other hand,the existence of backlash nonlinearity will reduce the rigidity of the transmission mechanism,affect the tracking performance of the system,and even lead to mechanical *** order to eliminate the influence of the backlash nonlinearity,the modeling and identification of the backlash nonlinearity are introduced,and the influence of the backlash is compensated in the *** addition,in order to reject the possible model deviation and uncertain interference,reduce steady states fluctuations,a high-order sliding mode observer（HOSMO） based nonsingular terminal sliding mode control（NTSMC） is *** simulation verification,the compound controller proposed in this paper can effectively reduce the influence of the backlash nonlinearity and improve the position tracking performance of the system.

关键词： Permanent Magnet Synchronous Motor(PMSM) Servo System Backlash Nonsingular Terminal Sliding Mode Control(NTSMC) High-order Sliding Mode Observer(HOSMO)

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农村老年家庭代际和谐动态模式研究

中国特色社会主义研究 2023年第6期 88-97页

作者：王萍王翔宇西安科技大学老龄社会发展研究所西安科技大学马克思主义学院

当前,农村老龄化程度持续深化,传统与现代更迭间的代际稳态被打破。通过采用跨越18年7期专项追踪数据,运用logistic模型从老年人视角探究农村家庭代际间双向的经济支持、器械支持和情感慰藉的交换动态模式。研究发现,家庭结构变动下代... 详细信息

当前,农村老龄化程度持续深化,传统与现代更迭间的代际稳态被打破。通过采用跨越18年7期专项追踪数据,运用logistic模型从老年人视角探究农村家庭代际间双向的经济支持、器械支持和情感慰藉的交换动态模式。研究发现,家庭结构变动下代际关系呈“形散核聚”态势,经济支持和器械支持呈向子(孙)代倾斜趋势,情感慰藉据不同家庭结构变动呈相异趋势。研究揭示,近20年中国农村老年家庭代际关系呈和谐动态模式,即“和则”与“谐则”的耦合发展模式,该模式兼有聚同存异的包容性和动态发展的韧性;该模式反映在追求家庭整体和谐发展中,动态代际交换呈柔性和谐发展,其运作机制为各项代际支持间持续优化、调适。政府、社会和社区大力弘扬中华优秀传统文化,倡导和谐社会发展观,加强构建家庭代际和谐能力,推进老龄友好型和谐社会的高质量发展。

关键词：农村老年家庭代际支持代际和谐动态模式家庭友好型社会

中国当代电影的影像运动造型与数字化视觉传达

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当代电影 2007年第6期 150-152页

作者：王翔宇上海师范大学数字传媒艺术中心广播电视编导专业助教200234

当代中国电影在画面视觉化创作方面取得了巨大成就。而影像运动造型是画面视觉传达中一项重要元素。在数字化背景下,运动造型创作得到发展的条件。不仅形成了以虚拟动线和非常态视角为特征的影像运动造型技术,还建立了有中国特色的装饰... 详细信息

当代中国电影在画面视觉化创作方面取得了巨大成就。而影像运动造型是画面视觉传达中一项重要元素。在数字化背景下,运动造型创作得到发展的条件。不仅形成了以虚拟动线和非常态视角为特征的影像运动造型技术,还建立了有中国特色的装饰化运动造型风格。中国电影的运动造型更应该体现视觉传达的中国意蕴和中国本土艺术意识。

关键词：运动造型视觉传达数字化装饰中国风格

超高分辨率机载SAR高精度子带拼接与处理方法研究

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电子与信息学报 2017年第10期39卷 2325-2331页

作者：王沛王翔宇李宁禹卫东王宇中国科学院电子学研究所北京100190 中国科学院大学北京100049

随着合成孔径雷达(SAR)的发展,对目标细节的观测越来越受到重视。SAR图像的分辨率越高,获取的细节信息就越多。目前,一种实用性较高的技术是,利用步进频率线性调频信号波形获取超高分辨率SAR图像。这种技术基于不同子带信号的步进载频关... 详细信息

随着合成孔径雷达(SAR)的发展,对目标细节的观测越来越受到重视。SAR图像的分辨率越高,获取的细节信息就越多。目前,一种实用性较高的技术是,利用步进频率线性调频信号波形获取超高分辨率SAR图像。这种技术基于不同子带信号的步进载频关系,通过子带拼接来合成大带宽信号。然而,子带拼接对于基带信号误差非常敏感,该文首先提出一种基于回归和统计学的信号预失真方案。在补偿完子带内的误差后,将子带间的误差转化为一个多变量的优化问题。最后,通过X波段机载SAR系统飞行实测数据验证了所提方法的有效性。

关键词：合成孔径雷达超高分辨率图像子带拼接技术幅相误差

Development of an Analytical Method for Evaluating the Catalytic Active Sites of Titanium Silicalite Zeolite

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Journal of Materials Science and Chemical Engineering 2015年第6期3卷 1-6页

作者： Xiaoyan Huang Yan Xue Xin Gao Baojun Li Yiqiang Wen xiangyu wang Institute of Industrial Catalysis College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou 450001 China Biological and Chemical Engineering College Nanyang Institute of Technology Nanyang 473004 China

A simple, quick, sensitive, accurate and precise method has been developed for evaluating the catalytic active sites of titanium silicalite-1 (TS-1). The catalytic active sites of titanium silicalite zeolite depend on the effectively active species (EAS) in TS-1 which react with specific substrates quickly. However, the EAS was hard to be evaluated with conventional instruments and techniques in the past. In this paper, the EAS was formed in TS-1 upon interaction with H2O2, and its presence could be confirmed by UV-vis spectroscopy which has an absorption peak at 385 nm. The absorbance at 385 nm was found to be linearly related to time, and when the absorbance and the increasing rate of absorbance (k) increased, the catalytic performance of TS-1 enhanced.

关键词： Effectively Active Species (EAS) Titanium Silicalite Zeolite UV-Vis Spectrum Absorbance

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海洋赤潮生物检测技术研究进展

高技术通讯 2005年第6期15卷 106-110页

作者：刘涛陈省平王翔宇中国海洋大学生命科学与技术学部青岛266003 中山大学广州510275

赤潮是我国近海主要的多发性海洋生态灾害,加强赤潮生物检测技术研究,对于赤潮预报与治理工作具有重要的现实意义.本文综述了海洋水色遥感监测技术、赤潮生物光学检测技术及赤潮生物生物学分析技术的研究现状及其发展趋势.

关键词：技术研究进展海洋赤潮生物检测技术海洋水色遥感生态灾害治理工作赤潮预报监测技术发展趋势研究现状分析技术赤潮生物生物光学多发性生物学