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Power Allocation for SE Maximization in Uplink Massive MIMO System Under Minimum Rate Constraint

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China Communications 2024年第3期21卷 104-117页

作者： Wang Hui yu xiangbin Liu Fuyuan Bai Jiawei College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

In this paper,we optimize the spectrum efficiency(SE)of uplink massive multiple-input multiple-output(MIMO)system with imperfect channel state information(CSI)over Rayleigh fading *** SE optimization problem is formulated under the constraints of maximum power and minimum rate of each ***,we develop a near-optimal power allocation(PA)scheme by using the successive convex approximation(SCA)method,Lagrange multiplier method,and block coordinate descent(BCD)method,and it can obtain almost the same SE as the benchmark scheme with lower *** this scheme needs three-layer iteration,a suboptimal PA scheme is developed to further reduce the complexity,where the characteristic of massive MIMO(i.e.,numerous receive antennas)is utilized for convex reformulation,and the rate constraint is converted to linear *** suboptimal scheme only needs single-layer iteration,thus has lower complexity than the near-optimal ***,we joint design the pilot power and data power to further improve the performance,and propose an two-stage algorithm to obtain joint *** results verify the effectiveness of the proposed schemes,and superior SE performance is achieved.

关键词： imperfect CSI massive MIMO minimum rate constraint power allocation spectral efficiency

Performance Analysis of Spatial Modulation Aided UAV Communication Systems in Cooperative Relay Networks

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Chinese Journal of Electronics 2024年

作者： xiangbin yu Mingfeng XIE Ning LI Cuimin PAN College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Millimeter Waves Southeast University

In this paper, by introducing the spatial modulation(SM) scheme into the unmanned aerial vehicle(UAV) relaying system, a SM-aided UAV(SM-UAV) cooperative relay network is presented. The performance of the SM-UAV relay network is investigated over Nakagami-m fading channels, where the UAV remains stationary over a given area. According to the performance analysis, using the amplify-and-forward(AF) protocol, the effective signalto-noise ratio(SNR) and the corresponding probability density function and moment generating function are, respectively, derived. With these results, the average bit error rate(BER) is further deduced, and resultant approximate closed-form expression is achieved. Based on the approximate BER, we derive the asymptotic BER to characterize the error performance of the system at high SNR. With this asymptotic BER, the diversity gain of the system is derived, and the resulting diversity order is attained. Simulation results illustrate the effectiveness of the performance analysis. Namely, approximate BER has the value close to the simulated one, and asymptotic BER can match the corresponding simulation well at high SNR. Thus, the BER performance of the system can be effectively assessed in theory, and conventional simulation will be avoided. Besides, the impacts of the antenna number, modulation order,fading parameter and UAV position on the system performance are also analyzed. The results indicate that the BER performance is increased with the increases of Nakagami parameter m and/or receive antenna and/or the decrease of modulation order.

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Cross-layer Design for Space-time Block Coded MIMO Systems with Imperfect Channel State Information

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Cross-layer Design for Space-time Block Coded MIMO Systems w...

Synthesis of NO by rotating sliding arc discharge reactor with conical-spiral electrodes

2012 IEEE International Conference on Computer Science and Automation Engineering（CSAE 2012）

作者： xiangbin yu 1 2 Wenting Tan 1 1 College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing China Xin Yin 1 Xiaomin Chen 1 Ying Yang 1 2 National Mobile Communication Research Laboratory Southeast University Nanjing China

By combining adaptive modulation （AM） and automatic repeat request （ARQ）, a cross-layer design （CLD） scheme for MIMO system with space-time block coding （STBC） and imperfect channel state information （CSI） is presented in this paper, and the effect of the imperfect CSI on the system performance is investigated. Based on the imperfect CSI, the probability density function of the effective signal to noise ratio （SNR） is derived, and the fading gain switching thresholds subject to a target packet loss rate and fixed power constraint are also derived. According to these results, closed-form expressions of the average spectrum efficiency （SE） and packet error rate （PER） of the system are further derived, respectively. These derived expressions include some existing expressions with perfect CSI as special cases, and can provide good performance evaluation for the CLD system with imperfect CSI. Numerical results verify the validity of the theoretical analysis. The results show that the SE and PER of the system with imperfect CSI are worse than those with perfect CSI due to the estimation error, but their performance difference will be reduced as estimation accuracy increases.

关键词： cross-layer design imperfect CSI spectrum efficiency space-time block coding MIMO packet error rate

来源： cnki会议评论

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Plasma Science and Technology 2024年第9期26卷 97-108页

作者： Bingyan CHEN Qi LIU Xu LI Chunyang ZHANG xiangbin GUO Qingzhou yu Zhicheng TANG Xiang HE Wei SU Yongfeng JIANG College of Mechanics and Engineering Science Hohai UniversityNanjing 211100People’s Republic of China College of Mechanical and Electrical Engineering Hohai UniversityChangzhou 213200People’s Republic of China College of Materials Science and Engineering Hohai UniversityChangzhou 213200People’s Republic of China College of Information Science and Engineering Hohai UniversityChangzhou 213200People’s Republic of China

The present work investigates the potential applications of nitrogen oxides(NO_(x)),particularly nitric oxide(NO)and nitrogen dioxide(NO2),generated through discharge plasma in diverse sectors such as medicine,nitrogen fixation,energy,and environmental *** this study,a rotating sliding arc discharge reactor was initially employed to produce high concentrations of gaseous NO_(x),followed by the utilization of a molybdenum wire redox reactor for NO2-to-NO *** outcomes reveal that the discharge states and generations of NO_(x) are affected by varying parameters,including the applied energies,frequencies and airflow states(1.3-2.6 m/s are the laminar flow,2.6-5.2 m/s are the transition state,5.2-6.5 m/s are the turbulent flow),and the concentrations of NO_(x) within the arc discharge are higher than that in the spark ***,the concentrations of NO,NO2 and NO_(x) gradually increased,and the concentration ratios of NO/NO2 and NO_(x)/NO2 decreased with increasing the applied energy for one cycle from 14.8 mJ to 24.3 ***,the concentrations of NO,NO2 and NO_(x) gradually decreased,and the concentration ratios of NO/NO2 and NO_(x)/NO2 first decreased and then increased with increasing the applied frequencies from 5.0 kHz to 9.0 ***,the concentrations of NO,NO2 and NO_(x) gradually decreased,and the concentration ratios of NO/NO2 and NO_(x)/NO2 first increased and then decreased with increasing the air flow speeds from 1.3 m/s to 6.5 m/***,the concentrations of NO increased and NO2 decreased with increasing temperature from 25°C to 400°C using molybdenum *** findings provide experimental support for the application of plasma in the fields of medicine,nitrogen fixation,energy and environmental protection.

关键词： rotating sliding arc discharge NO_(x) synthesis of NO redox reaction

硬件损伤下多窃听器NOMA系统平均保密容量分析

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第2期41卷 244-252页

作者：何安苏虞湘宾周玥南京航空航天大学电子信息工程学院中国南京211106 中国科学院无线传感器网络与通信重点实验室中国上海200050

研究了非正交多址(Non‑orthogonal‑multiple‑access,NOMA)接入通信系统的物理层安全性能。当基站采用下行NOMA方案发送信息时,由于信道的开放性,信息容易被窃听,而当存在多个随机分布的窃听者时,安全性能会进一步降低。为了增强存在硬... 详细信息

研究了非正交多址(Non‑orthogonal‑multiple‑access,NOMA)接入通信系统的物理层安全性能。当基站采用下行NOMA方案发送信息时,由于信道的开放性,信息容易被窃听,而当存在多个随机分布的窃听者时,安全性能会进一步降低。为了增强存在硬件损伤系统的物理层安全性能,本文考虑保护区的方法,针对地面用户与基站之间存在直连链路的情况,采用莱斯衰落来建模小尺度衰落。本文还假设多个窃听者的位置遵循齐次泊松点过程(Homogeneous Poisson point process,HPPP),借助高斯切比雪夫积分公式,推导了平均保密容量的闭式表达式,并给出了在高信噪比情况下的渐近表达式来获得进一步见解。仿真结果验证了保护区方法在增强安全性能方面的有效性,并说明了不同参数对系统保密性能的影响。

关键词：平均保密容量非正交多址硬件损伤莱斯衰落物理层安全

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芦荟治疗便秘的研究进展

中草药 2024年第11期55卷 3874-3885页

作者：黄炜锐余祥彬余越福建医科大学药学院福建福州350122 福建省新药安全评价中心福建福州350122

便秘是临床上常见的、多发病性消化系统疾病,严重影响患者的生活质量。目前化学药虽然在短期内能够取得显著的成效,但长期使用却往往存在疗效逐渐减弱的问题,可能与人体对化学药的耐受性逐渐增强,及对人体的不良反应逐渐显现有关。相比... 详细信息

便秘是临床上常见的、多发病性消化系统疾病,严重影响患者的生活质量。目前化学药虽然在短期内能够取得显著的成效,但长期使用却往往存在疗效逐渐减弱的问题,可能与人体对化学药的耐受性逐渐增强,及对人体的不良反应逐渐显现有关。相比之下,芦荟Aloe作为一种历史悠久的天然药物,在治疗便秘方面具有悠久的历史和广泛的应用。研究表明,芦荟具有治疗胃溃疡、泻下通便、调节肠道菌群组成和改善肠黏膜屏障功能等作用,可以有效治疗便秘。通过对芦荟治疗便秘的研究进展进行综述,旨在更全面地展示芦荟在治疗便秘方面的潜在应用价值,为今后芦荟的深入研究应用与治疗便秘相关药物的研发提供一定的参考价值。

关键词：芦荟好望角芦荟库拉索芦荟便秘泻下芦荟大黄素芦荟苷水通道蛋白肠神经系统肠道菌群芦荟制剂

Low Stress TSV Arrays for High-Density Interconnection

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Engineering 2024年第7期38卷 201-208页

作者： Binbin Jiao Jingping Qiao Shiqi Jia Ruiwen Liu Xueyong Wei Shichang yun Yanmei Kong yuxin Ye xiangbin Du Lihang yu Bo Cong Institute of Microelectronics Chinese Academy of SciencesBeijing 100000China School of Integrated Circuits University of Chinese Academy of SciencesBeijing 100000China State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong UniversityXi’an 710049China

In three-dimensional(3D)stacking,the thermal stress of through-silicon via(TSV)has a significant influence on chip performance and reliability,and this problem is exacerbated in high-density TSV *** this study,a novel hollow tungsten TSV(W-TSV)is presented and *** hollow structure provides space for the release of thermal *** results showed that the hollow W-TSV structure can release 60.3%of thermal stress within the top 2 lm from the surface,and thermal stress can be decreased to less than 20 MPa in the radial area of 3 *** ultra-high-density(1600 TSV∙mm2)TSV array with a size of 640×512,a pitch of 25 lm,and an aspect ratio of 20.3 was fabricated,and the test results demonstrated that the proposed TSV has excellent electrical and reliability *** average resistance of the TSV was 1.21 *** leakage current was 643 pA and the breakdown voltage was greater than 100 *** resistance change is less than 2%after 100 temperature cycles from40 to 125℃.Raman spectroscopy showed that the maximum stress on the wafer surface caused by the hollow W-TSV was 31.02 MPa,which means that there was no keep-out zone(KOZ)caused by the TSV *** results indicate that this structure has great potential for applications in large-array photodetectors and 3D integrated circuits.

关键词： Thermal stress Through-silicon via(TSV)High-density integration

In vitro bench testing using patient-specific 3D models for percutaneous pulmonary valve implantation with Venus P-valve

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Chinese Medical Journal 2024年第8期137卷 990-996页

作者： yu Han Zehua Shao Zirui Sun Yan Han Hongdang Xu Shubo Song xiangbin Pan Peter P.T.de Jaegere Taibing Fan Gejun Zhang Department of Structure Heart Disease Central China Fuwai Hospital of Zhengzhou UniversityZhengzhouHenan 451460China Children’s Heart Center Central China Fuwai Hospital of Zhengzhou UniversityZhengzhouHenan 451460China Department of Anesthesiology Central China Fuwai Hospital of Zhengzhou UniversityZhengzhouHenan 451460China Department of Structure Heart Disease Fuwai Hospital Chinese Academy of Medical SciencesBeijing 100037China Department of Cardiology Erasmus MCRotterdam 3015 GDNetherlands

Background:Due to the wide variety of morphology,size,and dynamics,selecting an optimal valve size and location poses great difficulty in percutaneous pulmonary valve implantation(PPVI).This study aimed to report our experience with in vitro bench testing using patient-specific three-dimensional(3D)-printed models for planning PPVI with the Venus ***:Patient-specific 3D soft models were generated using PolyJet printing with a compliant synthetic material in 15 patients scheduled to undergo PPVI between July 2018 and July 2020 in Central China Fuwai Hospital of Zhengzhou ***:3D model bench testing altered treatment strategy in all patients(100%).One patient was referred for surgery because testing revealed that even the largest Venus P-valve would not anchor *** the remaining 14 patients,valve size and/or implantation location was altered to avoid valve migration and/or compression coronary *** four patients,it was decided to change the point anchoring because of inverted cone-shaped right ventricular outflow tract(RVOT)(n=2)or risk of compression coronary artery(n=2).Concerning sizing,we found that an oversize of 2-5 mm *** of the valve was dictated by the flaring of the in-and outflow portion in the pulmonary *** was successful in all 14 patients(absence of valve migration,no coronary compression,and none-to-mild residual pulmonary regurgitation[PR]).The diameter of the Venus P-valve in the 3D simulation group was significantly smaller than that of the conventional planning group(36[2]vs.32[4],Z=-3.77,P1).Conclusions:In vitro testing indicated no need to oversize the Venus P-valve to the degree recommended by the balloon-sizing technique,as 2-5 mm sufficed.

关键词： Heart valve prosthesis implantation Percutaneous pulmonary valve intervention Pulmonary regurgitation bench testing 3D printing Venus P-valve

Power control scheme for multiple antenna systems with space-time coding in Rayleigh fading channels

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Journal of Systems Engineering and Electronics 2011年第5期22卷 730-738页

作者： xiangbin yu Guangguo Bi College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China National Mobile Communications Laboratory Southeast University Nanjing 210096 P. R. China

Two optimal power control （PC） schemes under the power constraint for space-time coded multiple input multiple output systems over the flat Rayleigh fading channel with the imperfect channel state information （CSI） are presented. One is based on the minimization of a bit error rate （BER）, and the other is based on the maximization of a fuzzy signal-to-noise ratio. In these schemes, different powers are allocated to individual transmit an- tennas rather than equal power in the conventional one. For the first scheme, the optimal PC procedure is developed. It is shown that the Lagrange multiplier for the constrained optimization in the power control does exist and is unique. A practical iterative algorithm based on Newton＇s method for finding the Lagrange multiplier is proposed. In the second scheme, some existing schemes are included, and a suboptimal PC procedure is developed by means of the asymptotic performance analysis. With this suboptimal scheme, a simple PC calculation formula is provided, and thus the calculation of the PC will be straightforward. Moreover, the suboptimal scheme has the BER performance close to the optimal scheme. Simulation results show that the two PC schemes can provide BER lower than the equal PC and antenna selection scheme under the imperfect CSI.

关键词： power control (PC) space-time coding imperfect channel state information (CSI) bit error rate (BER) signal-to- noise ratio (SNR).