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Reflecting Surface-Aided Device-to-Device Communications System

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Journal of Communications and Information Networks 2020年第4期5卷 403-410页

作者： Chiya Zhang Wenyu Chen Chunlong He xingquan li School of Electronic and Information Engineering Harbin Institute of TechnologyShenzhen 518055China.Peng Cheng Laboratory(PCL)Shenzhen 5180523China Guangdong Key Laboratory of Intelligent Information Processing Shenzhen UniversityShenzhen518060China

Intelligent reflecting surface(IRS)is a promising technology for its capability of reflecting the incident signal towards the desired *** can improve the efficiency of wireless communication *** paper introduces IRS into a device-to-device(D2D)communications system to improve the throughput of the D2D *** adopt the block coordinate descent al-gorithm and semidefinite relaxation technique to optimize the beamforming vector,power allocation and phase shift *** results demonstrate that IRS is able to enhance the throughput of the D2D communications system,and the proposed algorithm significantly outper-forms the other benchmark algorithms.

关键词： intelligent reflecting surface device-to-device communications block coordinate descent

Secure data rate maximization for full-duplex UAV-enabled base station

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Digital Communications and Networks 2024年第5期10卷 1387-1393页

作者： Chunlong He Xinjie li Yin Huang Jianzhen lin Gongbin Qian xingquan li Guangdong Key Laboratory of Intelligent Information Processing Shenzhen UniversityShenzhenChina National Mobile Communications Research Laboratory Southeast UniversityNanjing211189China Shenzhen Institute of Information Technology ShenzhenChina

Unmanned Aerial Vehicle(UAV)is an air base station featuring flexible deployment and *** can significantly improve the communication quality of the system due to its line-of-sight channel connection with ground ***,due to the openness of UAV-to-Ground channels,the communication between ground users'devices and UAV is easily *** this paper,we aim to improve the security of communication system by using full-duplex UAV as a mobile air base *** UAV sends interference signals to eavesdroppers and receives signals from ground *** jointly optimize the scheduling between the UAV and ground devices,the transmission power of the UAV and ground devices,as well as the trajectory of the UAV to maximize the minimum average security communication data *** optimization problem is mixed with integers and nonconvex ***,this problem is not a standard convex optimization problem,which can not be solved with standard *** this in mind,we propose an effective algorithm which solves this problem iteratively by applying Successive Convex Approximation(SCA),variable relaxation and ***,numerical results demonstrate the effectiveness of the proposed algorithm.

关键词： UAV relay Physical layer security Full-duplex UAV Power optimization Trajectory optimization

Power Minimization for the IRS-Aided SWIPT Secure Communication System with Imperfect Cascaded Channel

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Journal of Communications and Information Networks 2023年第2期8卷 133-140页

作者： Chunlong He Shuqiong Xu Gongbin Qian xingquan li Chiya Zhang Guangdong Key Laboratory of Intelligent Information Processing Shenzhen UniversityShenzhen 518060China School of Microelectronics Shenzhen Institute of Information TechnologyShenzhen 518000China School of Electronic and Information Engineering Harbin Institute of TechnologyShenzhen 518055China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Peng Cheng Laboratory(PCL) Shenzhen 5180523China

Intelligent reflecting surface(IRS)-assisted simultaneous wireless information and power transfer(SWIPT)is a promising technology for prolonging the lifetime of the users and improving system ***,it is challenging to obtain the perfect channel state information(CSI)at the base station(BS)due to the lack of radio frequency(RF)chains at the IRS,which becomes even harder when eavesdroppers(Eves)*** this paper,we study the power issues in the IRS-aided SWIPT system under the imperfect CSI of BS-IRS-Eves *** aim to minimize the transmitting power at the BS by jointly designing transmit beamforming and reflective beamforming with subject to the rate outage probability constraints of the Eves,the energy harvesting constraints of the energy receivers(ERs),and the minimum rate constraints of the information receivers(IRs).We use Bernstein-type inequality to solve the rate outage probability ***,the formulated nonconvex problem can be efficiently tackled by employing alternating optimization(AO)combined with semidefinite relaxation(SDR)and penalty convex-concave procedure(CCP).Numerical results demonstrate the effectiveness of the proposed scheme.

关键词： IRS SWIPT secure communication AO

Robust beamforming design for energy harvesting efficiency maximization in RIS-aided SWIPT system

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Digital Communications and Networks 2024年第06期 1804-1812页

作者： xingquan li Hongxia Zheng Chunlong He Xiaowen Tian Xin lin School of Microelectronics Shenzhen Institute of Information Technology School of Electronic and Communication Engineering Shenzhen Polytechnic University Guangdong Key Laboratory of Intelligent Information Processing Shenzhen University College of Physics and Electromechanical Engineering Jishou University Institute of Artificial Intelligence and Blockchain Guangzhou University

This paper investigates Energy Harvesting Efficiency(EHE) maximization problems for Reconfigurable Intelligent Surface(RIS) aided Simultaneous Wireless Information and Power Transfer(SWIPT). This system focuses on the imperfect RIS-related channel and explores the robust beamforming design to maximize the EHE of all energy receivers while respecting the maximum transmit power of the Access Point(AP), RIS phase shift constraints, and maintaining a minimum signal-to-interference plus noise ratio for all information receivers under both linear and non-linear EH models. To solve these non-convex problem, the channel uncertainty related infinite constraints are approximated by using the S-procedure. With the introduction of slack variables, the transformed subproblems can be iteratively solved using alternating algorithm. Simulation results demonstrate that RIS is able to increase the system EHE.

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Theoretical and Experimental Study of Explosion limits and the Inhibition of Flammable Refrigerants

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Journal of Software Engineering and Applications 2016年第10期9卷 501-515页

作者： Guansan Tian xingquan li Yunfeng Gao Fengxia Zhang School of Thermal Energy Engineering Shandong Jianzhu University Jinan China Key Laboratory of Renewable Energy Utilization Technology in Building of National Education Ministry Shandong Jianzhu University Jinan China Shandong Provincial Key Laboratory of Building Energy-Saving Technology Shandong Jianzhu University Jinan China

In this study, we analyze factors affecting the explosion limits of flammable refrigerants. We conclude that any method used for measuring flammable refrigerant explosion limits has its conditional restrictions. Flammable refrigerants in the atmosphere can also explode under certain conditions, when the concentration is approaching the explosion limits. An experimental study on the explosion limits of six kinds of flammable refrigerants is carried out with a mixture of refrigerant and combustible refrigerant, which has a similar effect to a flame retardant. An experimental apparatus was designed to test the explosion limits of mixtures made from three different nonflammable refrigerants and six different flammable refrigerants. Two practical models were developed to estimate the critical concentration for inhibiting explosion of refrigerant mixtures: one was made up of two flammable components with one nonflammable component, and the second was made up of one flammable component with two nonflammable components.

关键词： Flammable Refrigerants Explosion limits Impact Factors Inhibition

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液力变矩器性能参数的计算误差及其修正方法

西南交通大学学报 2012年第3期47卷 471-476页

作者：罗虹王腾腾李兴泉李英强重庆大学机械传动国家重点实验室重庆400030

为提高液力变矩器数值模拟的精度,采用CFD(computational fluid dynamics)方法对液力变矩器的变矩比、效率和泵轮容量系数等性能参数进行了计算,对计算误差进行了分析,并提出了相应的误差修正方法.通过分析补偿油液流动对泵轮容量系数... 详细信息

为提高液力变矩器数值模拟的精度,采用CFD(computational fluid dynamics)方法对液力变矩器的变矩比、效率和泵轮容量系数等性能参数进行了计算,对计算误差进行了分析,并提出了相应的误差修正方法.通过分析补偿油液流动对泵轮容量系数计算误差的影响,提出了针对泵轮容量系数误差的修正方法.结果表明:数值计算模型中,忽略摩擦损失和补偿油液流动的影响,将引起变矩器性能参数的计算误差;针对摩擦损失提出的误差修正方法,使算例中变矩器的变矩比和效率的最大相对误差均由16.2%减小到13.9%;按照泵轮容量系数误差的修正方法,泵轮容量系数的最大相对误差由13.9%减小到7.3%.

关键词：液力变矩器变矩器性能数值模拟误差修正

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基于再聚类和离散优化的k路划分算法

计算机辅助设计与图形学学报 2024年第3期36卷 473-484页

作者：潘萍梅刘欣恬李兴权朱文兴福州大学离散数学与理论计算机科学研究中心福州350116 福州大学数学与统计学院福州350116 鹏城实验室深圳518073 闽南师范大学数学与统计学院漳州363000

为了寻得集成电路更优的k路划分,提出将再聚类和离散优化应用于k路划分算法.首先利用再聚类缩小超图规模,即根据给定划分计算顶点间的评级函数值,依据取值大小进行顶点聚类;然后将超图转换为星型图,并将k路划分问题转换为无约束的离散... 详细信息

为了寻得集成电路更优的k路划分,提出将再聚类和离散优化应用于k路划分算法.首先利用再聚类缩小超图规模,即根据给定划分计算顶点间的评级函数值,依据取值大小进行顶点聚类;然后将超图转换为星型图,并将k路划分问题转换为无约束的离散优化问题;进而设计一个算法迭代移动增益值最大的顶点,在算法求解过程中放宽平衡约束,允许暂时处于不可行域的解,扩大问题的求解空间.在同一平台上使用ISPD98电路测试基准对所提算法、hMETIS-Kway和KaHyPar-K进行测试,并比较最小割值和运行时间.实验结果表明该算法优于hMETIS-Kway,特别是在k=2时,最小割值减少了0.173,速度提升了0.706.此外,该算法对KaHyPar-K也有相应的改进效果.

关键词： k路划分最小割超图聚类离散优化

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模态综合的子结构主模态截断方法

西南交通大学学报 2014年第1期49卷 173-178页

作者：李兴泉邓兆祥李传兵章竟成李英强汽车噪声振动和安全技术国家重点实验室重庆400039 重庆长安铃木汽车有限公司重庆401321 重庆大学机械传动国家重点实验室重庆400030

为了减少固定界面模态综合方法中保留的子结构主模态数，分别采用频率截断和有效模态质量截断两种方法进行截断，分析两种方法的适用性，最终得到适合结构低频动态特性计算的主模态截断方法．计算结果表明：频率截断法保留的主模态不到... 详细信息

为了减少固定界面模态综合方法中保留的子结构主模态数，分别采用频率截断和有效模态质量截断两种方法进行截断，分析两种方法的适用性，最终得到适合结构低频动态特性计算的主模态截断方法．计算结果表明：频率截断法保留的主模态不到有效质模态量截断法的1／2，采用2～3倍的最高关心频率进行主模态截断，能保证结构低频动态特性计算具有较高的精度，所保留的主模态，更能反应子结构在关心频率范围内系统振动的变形模式；有效模态质量法不能判断各子结构间主模态对系统动态特性作用的相对大小，这使小尺寸高刚度的子结构保留多余的模态，其计算效率较低．

关键词：模态综合子结构振动频率有效模态质量

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轿车液力变矩器叶片角的优化

汽车工程 2011年第6期33卷 517-520页

作者：李兴泉邓兆祥李英强古兴生重庆大学机械传动国家重点实验室重庆400030 汽车噪声振动和安全技术国家重点实验室重庆400039 重庆红宇精密工业有限责任公司重庆402760

提出兼顾动力性、经济性的轿车液力变矩器叶片角优化方法。建立以加权的最高效率、起动变矩比和泵轮转矩系数为目标函数的优化模型,对各叶片角进行优化。优化结果,在传动比i=0.8时,变矩比、效率和泵轮转矩系数分别比传统设计提高了4.3%,... 详细信息

提出兼顾动力性、经济性的轿车液力变矩器叶片角优化方法。建立以加权的最高效率、起动变矩比和泵轮转矩系数为目标函数的优化模型,对各叶片角进行优化。优化结果,在传动比i=0.8时,变矩比、效率和泵轮转矩系数分别比传统设计提高了4.3%,4.4%和28.5%。优化后的变矩器叶片角及其原始特性与国外同尺寸成熟产品比较接近。

关键词：液力变矩器叶片角优化效率变矩比