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Reduced K-best sphere decoding algorithm based on minimum route distance and noise variance

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Journal of Systems Engineering and Electronics 2014年第1期25卷 10-16页

作者： xinyu mao Jianjun Wu Haige Xiang School of Electronics Engineering and Computer Science Peking University

This paper focuses on reducing the complexity of K-best sphere decoding （SD） algorithm for the detection of uncoded multi-ple input multiple output （MIMO） systems. The proposed algorithm utilizes the threshold-pruning method to cut nodes with partial Euclidean distances （PEDs） larger than the threshold. Both the known noise value and the unknown noise value are considered to generate the threshold, which is the sum of the two values. The known noise value is the smal est PED of signals in the detected layers. The unknown noise value is generated by the noise power, the quality of service （QoS） and the signal-to-noise ratio （SNR） bound. Simulation results show that by considering both two noise values, the proposed algorithm makes an efficient reduction while the performance drops little.

关键词： chi-square distribution (CSD) K-best sphere decoding(SD) multiple input multiple output (MIMO) systems.

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天灸罐灸甜美穴戒烟的临床研究

中国中医药现代远程教育 2024年第18期22卷 107-110页

作者：葛文品毛新宇重庆三峡医药高等专科学校重庆404000

目的探讨天灸罐灸甜美穴戒烟的临床应用效果。方法选择2018年10月—2019年11月收治的需要戒烟的患者210例,随机分为对照组和观察组,每组105例。对照组给予药物戒烟,观察组在对照组基础上予天灸罐灸甜美穴戒烟,评估两组戒烟效果,比较其... 详细信息

目的探讨天灸罐灸甜美穴戒烟的临床应用效果。方法选择2018年10月—2019年11月收治的需要戒烟的患者210例,随机分为对照组和观察组,每组105例。对照组给予药物戒烟,观察组在对照组基础上予天灸罐灸甜美穴戒烟,评估两组戒烟效果,比较其烟草依赖情况及临床疗效。结果治疗后,观察组烟草依赖性降低情况明显优于对照组(P<0.05)。观察组治疗总有效率为85.71%(90/105),高于对照组的69.52%(73/105)(P<0.05)。结论天灸罐灸甜美穴戒烟效果较为显著,能够明显降低患者对烟草的依赖性,值得临床推广应用。

关键词：戒烟天灸罐疗法甜美穴

基于双折减系数法与极限平衡法的顺层滑坡稳定性分析

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华北水利水电大学学报（自然科学版） 2024年第6期45卷 81-88页

作者：李小根盛济铭王静刘泓辰毛新宇华北水利水电大学河南郑州450046

以四川省布拖县龙潭乡冯家坪滑坡为例,利用FLAC3D软件设计了基于双折减系数法的滑坡稳定性分析程序,应用“GIS-Rhino-FLAC3D”耦合技术建立三维地质体模型。考虑黏聚力和内摩擦角在滑坡失稳过程中衰减速度和弱化程度的不同,以及非饱和... 详细信息

以四川省布拖县龙潭乡冯家坪滑坡为例,利用FLAC3D软件设计了基于双折减系数法的滑坡稳定性分析程序,应用“GIS-Rhino-FLAC3D”耦合技术建立三维地质体模型。考虑黏聚力和内摩擦角在滑坡失稳过程中衰减速度和弱化程度的不同,以及非饱和土中基质吸力对土体抗剪强度的影响,提出一种以黏聚力和摩擦力的衰减权重定义综合安全系数的双折减系数法,并采用极限平衡法作对比计算,研究分析了顺层滑坡的稳定性。结果表明:设计的抗剪强度参数双折减程序可以得出安全系数云图,直观地反映滑坡安全系数的空间分布特征;与传统强度折减法相比,所提出的双折减系数法计算的滑动面分布范围和综合安全系数更精确,较极限平衡法误差更小,可以准确地反映滑坡的稳定状态。研究结果可为双折减系数法应用于滑坡灾害的防治提供参考。

关键词：顺层滑坡极限平衡法双折减系数法 GIS-Rhino-FLAC3D 稳定性分析

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基于深度学习的无锚框目标检测算法综述

机床与液压 2024年第1期52卷 202-209页

作者：高海涛朱超涵张天棋郝飞茅新宇南京工程学院机械工程学院江苏南京211167

近年来,基于深度学习的无锚框目标检测算法备受关注。为了深入理解无锚框检测算法,对比分析了基于深度学习的无锚框检测算法的原理机制、网络结构、核心特性以及优缺点,归纳总结了无锚框检测算法的核心技术,并在同一数据集上通过性能实... 详细信息

近年来,基于深度学习的无锚框目标检测算法备受关注。为了深入理解无锚框检测算法,对比分析了基于深度学习的无锚框检测算法的原理机制、网络结构、核心特性以及优缺点,归纳总结了无锚框检测算法的核心技术,并在同一数据集上通过性能实验研究上述算法的性能,总结提出基于深度学习的目标检测算法未来的研究方向。

关键词：无锚框目标检测算法深度学习算法比较

分布式无人机载InSAR混合多基线相位解缠与高程反演技术

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信号处理 2024年第9期40卷 1685-1695页

作者：明星辰王朝栋毛馨玉李中余武俊杰杨建宇电子科技大学信息与通信工程学院四川成都611731

干涉合成孔径雷达技术(Interferometric Synthetic Aperture Radar,InSAR)作为地形测高的主要途径之一,可以获取地面场景的数字高程模型(Digital Elevation Model,DEM),实现复杂地貌的立体感知。分布式InSAR系统可以灵活改变构型,具备... 详细信息

干涉合成孔径雷达技术(Interferometric Synthetic Aperture Radar,InSAR)作为地形测高的主要途径之一,可以获取地面场景的数字高程模型(Digital Elevation Model,DEM),实现复杂地貌的立体感知。分布式InSAR系统可以灵活改变构型,具备柔性基线的特性,突破单站多通道InSAR的基线限制,有利于提高高程反演的精度,满足不同地形的需求,在复杂地理测绘、资源勘测、侦察预警等方面具有重要应用前景。现存的分布式InSAR系统以星载编队为主,构型有较大的限制,针对机载系统的研究尚少且都以双站单基线为主,对复杂陡峭地形的反演精度较低,甚至无法适用。针对现有系统的缺陷,本文提出了基于混合基线的分布式多基线无人机载InSAR高程反演系统,并改进InSAR技术以适配提出的新型体制。本文首先介绍了分布式混合基线无人机载InSAR系统的几何构型,并推导了本系统高程反演的原理;然后对比现有系统,阐述了适配分布式系统构型的相位解缠的技术优势并推导其实现方法,从理论上论证了本文提出的灵活构型的干涉系统对于复杂陡峭场景的适用性;最后通过对仿真地形、真实山地地形的仿真实验,实现了分布式混合基线无人机载InSAR系统对地物目标场景的高程反演,验证了本系统技术的可行性;并通过与现有系统的对比分析,凸显了本系统在复杂地形高程信息反演方面的优越性。

关键词：干涉合成孔径雷达分布式雷达系统机载合成孔径雷达高程反演相位解缠

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王浆酸及其护肤功效的研究进展

日用化学工业（中英文） 2024年第2期54卷 209-215页

作者：杲款款杨素珍韩婷婷李燕袁春颖毛欣宇山东福瑞达生物股份有限公司山东济南250101

王浆酸简称10-HDA(10-Hydroxy-2-Decenoic acid,10-HDA),是蜂王浆中的一种不饱和脂肪酸。在自然界,目前只存在于蜂王浆中,且难以分离获取,生物合成法将有望解决王浆酸原料获取困难、价格昂贵的现状。王浆酸具有很强的生物活性,在抑菌、... 详细信息

王浆酸简称10-HDA(10-Hydroxy-2-Decenoic acid,10-HDA),是蜂王浆中的一种不饱和脂肪酸。在自然界,目前只存在于蜂王浆中,且难以分离获取,生物合成法将有望解决王浆酸原料获取困难、价格昂贵的现状。王浆酸具有很强的生物活性,在抑菌、抗炎、抗癌、抗氧化等功效,在食品、医药、保健品、化妆品方面有广泛的应用前景。目前随着时代的发展与市场的变化,化妆品原料的不断研发将会是提升化妆品品质的关键。文章综述了王浆酸在抗衰、抗炎、美白、抗氧化、抑菌方面的功效,以期为王浆酸在护肤品中的应用提供理论依据,为化妆品公司在开发新型、高效、多种用途的护肤原料上提供新的选择。

关键词：王浆酸 10-HDA 护肤品生物活性应用研究

Controllable preparation of graphene glass fiber fabric towards mass production and its application in self-adaptive thermal management

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Science Bulletin 2024年第17期69卷 2712-2722页

作者： Ruojuan Liu Fan Yang Shuting Cheng Xianghe Yue Fushun Liang Wenjuan Li Jingnan Wang Qinchi Zhang Liangyu Zou Hao Yuan Yuyao Yang Kangyi Zheng Longfei Liu Mengxiong Liu Wei Gu Ce Tu xinyu mao Xiaobai Wang Yue Qi Zhongfan Liu Centre for Nanochemistry Beijing Science and Engineering Centre for NanocarbonsBeijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Beijing Graphene Institute(BGI) Beijing 100095China State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing 102249China School of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China Soochow Institute for Energy and Materials Innovations(SIEMIS) College of EnergySoochow UniversitySuzhou 215006China Academy for Advanced Interdisciplinary Research North University of ChinaTaiyuan 030051China Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China

Direct synthesis of graphene on nonmetallic substrates via chemical vapor deposition (CVD) has become a frontier research realm targeting transfer-free applications of CVD ***,the stable mass production of graphene with a favorable growth rate and quality remains a grand ***,graphene glass fiber fabric (GGFF) was successfully developed through the controllable growth of graphene on non-catalytic glass fiber fabric,employing a synergistic binary-precursor CVD strategy to alleviate the dilemma between growth rate and *** binary precursors consisted of acetylene and acetone,where acetylene with high decomposition efficiency fed rapid graphene growth while oxygencontaining acetone was adopted for improving the layer uniformity and ***,the bifurcating introducing-confluent premixing (BI-CP) system was self-built for the controllable introduction of gas and liquid precursors,enabling the stable production of *** features solar absorption and infrared emission properties,based on which the self-adaptive dual-mode thermal management film was *** film can automatically switch between heating and cooling modes by spontaneously perceiving the temperature,achieving excellent thermal management performances with heating and cooling power of~501.2 and~108.6 W m-2,*** findings unlock a new strategy for the large-scale batch production of graphene materials and inspire advanced possibilities for further applications.

关键词： Graphene Graphene glass fiber fabric Synergistic binary-precursor strategy Mass production Thermal management

A DHT-based fast handover management scheme for mobile identifier/locator separation networks

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Science China(Information Sciences) 2013年第12期56卷 222-236页

作者： ZHAI YuJia mao xinyu WANG Yue YUAN Jian REN Yong Department of Electronic Engineering Tsinghua University

Several researches propose the identifer/locator separation architecture to tackle the scaling problems of today’s Internet routing and addressing *** scalable and seamless mobility support is an important task in mobile identifer/locator separation *** this paper,by analyzing the features,such as direct separation,flexible mapping and identifer replacement,we show that the new architecture delivers data packets more efciently and protects location privacy better than traditional mobile IP networks,and is able to implement soft handover *** we present a distributed Hash table(DHT)based fast handover management(DFHM)scheme for the new architecture,which improves the reactive handover mode of FMIPv6 and eliminates the duplicate address detection(DAD)and return routability(RR)processes in *** we propose a generic analysis framework for handover ***,we demonstrate the validity of our framework by simulation and quantifcationally study the efects of network scale and movement *** results show that DFHM has good scalability and low handover latency,and has great advantages in the signaling cost and fast mobility support.

关键词： handover management DHT-based management structure mobile identifer/locator separation networks analysis framework

Reduction of friction by normal oscillations.Ⅱ.In-plane system dynamics

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Friction 2017年第2期5卷 534-535,536页

作者： xinyu mao Valentin L.POPOV Jasminka STARCEVIC Mikhail POPOV Technische Universit(a)t Berlin Berlin 10623 GermanyTsinghua University Beijing 100084 China Technische Universit(a)t Berlin Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Technische Universit(a)t Berlin Berlin 10623 GermanyTomsk State University Tomsk 634050 Russia

The influence of out-of-plane oscillations on friction is a well-known phenomenon that has been studied extensively with various experimental methods,e.g.,pin-on-disk ***,existing theoretical models have yet achieved only qualitative correspondence with *** we argue that this may be due to the system dynamics (mass and tangential stiffness) of the pin or other system components being *** paper builds on the results of a previous study [19] by taking the stiffness and resulting dynamics of the system into *** main governing parameters determining macroscopic friction,including a dimensionless oscillation amplitude,a dimensionless sliding velocity and the relation between three characteristic frequencies (that of externally excited oscillation and two natural oscillation frequencies associated with the contact stiffness and the system stiffness) are *** the limiting cases of a very soft system and a very stiff system,our results reproduce the results of previous *** between these two limiting cases there is also a resonant case,which is studied here for the first *** resonant case is notable in that it lacks a critical sliding velocity,above which oscillations no longer reduce *** obtained for the resonant case are qualitatively supported by experiments.

关键词： sliding friction out-of-plane oscillation stiffness system dynamics macroscopic friction coefficient