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Chinese Journal of Electronics 2017年第3期26卷 600-607页

作者： TANG Rui ZHAO Jihong qu hua School of Electronics and Information Engineering Xi'an Jiaotong University School of Communication and Information Engineering Xi'an University of Posts and Telecommunications

Device-to-Device(D2D)communication is viewed as an emerging technology in the fifth generation systems to fully explore the proximate gain residing in local communicating pairs.But the interference imposed to the existing Cellular links(C-link)should be addressed in the optimization for underlaid D2D links(D-link).There is a performance tradeoff between Energy conservation(EC)and the number of links with satisfied quality-of-service(Qo S)requirement or System capacity(SC).We aim to weight the above tradeoff for D-links by specifying it into optimizing EC on the condition that SC is maximized and Qo S requirements of C-links are fully guaranteed.A threestage joint power control and channel assignment mechanism is proposed including feasibility check,SC maximization and greedy optimization for EC.Thanks to numerical results,we illustrate the necessity to conduct our performance tradeoff and observe the gain when multiple resource variables are in elaborate cooperation.

关键词： Device-to-Device(D2D) communication Energy conservation User fairness Resource allocation

Emergence of highly pathogenic avian influenza A(H5N8)clade 2.3.4.4b viruses in grebes in Inner Mongolia and Ningxia,China,in 2021

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Journal of Integrative Agriculture 2024年第1期23卷 348-353页

作者： Qiuzi Xu Xinru Lü Yi Li hua Luo Zhen Zhang Xiang Li Rongxiu Qin Qing An Fengyi qu Zhenliang Zhao Chengbo Zhang Weidong Wang Yuecheng Li Yajun Wang Xiangwei Zeng Zhijun Hou Jingqiang Ren Yulong Wang Yanbing Li Hongliang Chai College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040China Harbin Veterinary Research Institute Chinese Academy of Agricultural SciencesHarbin 150040China Wenzhou Key Laboratory for Virology and Immunology Institute of VirologyWenzhou UniversityWenzhou 325000China Ordos Forestry and Grassland Administration Ordos 017000China Monitoring Center for Terrestrial Wildlife Epidemic Diseases Yinchuan 750000China

Highly pathogenic avian influenza(HPAI)subtype H5Nx viruses have spread globally and are a major concern for poultry,wild birds,mammals,and even humans(de Vries et al.2015;Zeng et al.2022).The hemagglutinin(HA)genes of H5 subtype viruses have evolved into multiple clades and some of these clades have been further divided into subclades(Cui et al.2022).Clade 2.***.4.4H5N8 HPAI viruses(HPAIVs)have caused several waves of disease outbreaks in wild birds and domestic poultry(Wang et al.2022).

关键词： poultry Ningxia influenza

预埋承插式接头错缝拼装盾构隧道受力性能及管片开裂原因分析

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城市轨道交通研究 2024年第S1期27卷 73-78页

作者：瞿欣阳邵华上海地铁维护保障有限公司工务分公司上海200233

[目的]以上海轨道交通某区段新型隧道顶部管片开裂为背景,分析预埋承插式接头错缝拼装隧道在外荷载作用下变形特点及管片开裂原因,并提出此类隧道的运维侧重点。[方法]根据盾构推进时间、保护区历年变化及隧道收敛变形数据,分析了隧道... 详细信息

[目的]以上海轨道交通某区段新型隧道顶部管片开裂为背景,分析预埋承插式接头错缝拼装隧道在外荷载作用下变形特点及管片开裂原因,并提出此类隧道的运维侧重点。[方法]根据盾构推进时间、保护区历年变化及隧道收敛变形数据,分析了隧道管片开裂原因。并且发现顶部有无拼接缝的隧道环,在变形程度及裂缝产生方面存在差异。通过与相同环境下单圆通缝隧道收敛变形数据进行对比,得出了新型隧道与单圆通缝隧道受力性能的异同及相对刚度。[结果及结论]此次管片开裂是由侧方拔桩施工导致水平方向土压力变小以及正上方填土使得竖直方向土压力增大两者叠加产生的。顶部为整块管片的隧道环相较顶部为拼接缝的收敛变形更小,但容易开裂,运维时宜重点关注顶部为整块管片隧道环的收敛变形数据。新型隧道横断面刚度约为单圆通缝隧道的2.5倍,峰值处的荷载会传递到邻近的隧道环共同承担,使得隧道收敛变形较为平缓,隧道在外荷载消除后变形恢复能力更强。因这种裂缝而产生的渗漏水病害及通路很难通过隧道回缩愈合。

关键词：上海轨道交通盾构隧道错缝拼装预埋承插式接头管片收敛变形

Energy-Efficient Cooperative Strategy in RF Energy Harvesting Cognitive Radio Network

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Chinese Journal of Electronics 2019年第3期28卷 651-657页

作者： YAN Feiyu ZHAO Jihong qu hua XU Xiguang School of Electronic and Information Engineering Xi'an Jiaotong University School of Communication and Information Engineering Xi'an University of Posts and Telecommunications

Energy-efficient cooperative spectrum sharing has become a new trend based on financial and environmental considerations. We focus on a novel energy-efficient cooperative strategy in a Radio frequency(RF) energy harvesting cognitive radio network, where the Secondary user(SU) provides energy supply and relaying assist for the Primary user(PU) in exchange for the transmission opportunities. On the basis of energy and information cooperation, an Energy efficiency(EE)maximization non-convex problem for SU is formulated under the PU’s quality of service(QoS) requirement and energy-causality constraint. With the aid of Dinkebalch’s method and convex optimization technique, a joint time and power allocation scheme is proposed. Numerical results show that the proposed scheme achieves higher SU’s EE and better PU’s QoS guarantee compared to the scheme in which the SU only provides energy for the PU’s transmission.

关键词： Cognitive radio network Radio frequency(RF) energy harvesting Cooperative communication Energy efficiency Resource management

A Robust Fuzzy Time Series Forecasting Method Based on Multi-partition and Outlier Detection

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Chinese Journal of Electronics 2019年第5期28卷 899-905页

作者： qu hua ZHANG Yanpeng LIU Wei ZHAO Jihong School of Software Engineering Xi'an Jiaotong University School of Electronics and Information Engineering Xi'an Jiaotong University School of Communication and Information Engineering Xi'an University of Posts and Telecommunication

We propose a robust fuzzy time series forecasting method based on multi-partition approach and outlier detection for forecasting market prices. The multipartition approach employs a specific partition criterion for each dimension of the time series. We use a Gaussian kernel version fuzzy C-means clustering to construct the fuzzy logic relationships and detect the outliers by calculating the grade of membership. We apply an additional model, which is trained on the set of outliers by Levenberg-Marquardt algorithm, for forecasting the outliers in testing set. The experiment results show that the proposed method improves the robustness and the average forecasting accuracy rate.

关键词： Fuzzy time series Multi-partition approach Outlier detection

Joint Optimization of Channel Allocation,Link Assignment and Power Control for Device-to-Device Communication Underlaying Cellular Network

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China Communications 2015年第12期12卷 92-100页

Device-to-Device(D2D) communication has been proposed to facilitate cellular network with system capacity(SC) and quality of service(QoS).We consider the design of link assignment(LA),channel allocation(CA)and power control(PC) in D2D-aided content delivery scenario for both user fairness(UF)and system throughput(ST) under QoS requirement.Due to the complexity of the problem,we decompose it into two components:CA is formulated from graph perspective to mitigate severe co-channel interference,which turns out to be the Max K-cut problem;LA and PC are jointly optimized to utilize the gain achieved from CA for supreme performance,and specifically,genetic algorithm(GA) is adopted to optimize LA,but when deriving the fitness of each chromosome,PC optimization will be involved.Thanks to numerical results,we elucidate the efficacy of our scheme.

关键词：网络设备联合优化信道分配功率控制链路分配蜂窝网络通信 QoS要求

Distributed Power Control for Energy Conservation in Hybrid Cellular Network with Device-to-Device Communication

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China Communications 2014年第3期11卷 27-39页

作者： TANG Rui ZHAO Jihong qu hua School of Electronics and Information Engineering Xi'an Jiaotong University Xi'an 710049 Shaanxi Province P. R. China School of Communication and Information Engineering Xi'an University of Posts and Telecommunications Xi'an 710061 ShaanxiProvince P. R. China

Device-to-Device(D2D) communication has been proposed as a promising implementation of green communication to benefit the existed cellular network.In order to limit cross-tier interference while explore the gain of short-range communication,we devise a series of distributed power control(DPC) schemes for energy conservation(EC)and enhancement of radio resource utilization in the hybrid system.Firstly,a constrained opportunistic power control model is built up to take advantage of the interference avoidance methodology in the presence of service requirement and power constraint.Then,biasing scheme and admission control are added to evade ineffective power consumption and maintain the feasibility of the system.Upon feasibility,a non-cooperative game is further formulated to exploit the profit in EC with minor influence on spectral efficiency(SE).The convergence of the DPC schemes is validated and their performance is confirmed via simulation results.

关键词：分布式功率控制电源控制设备短距离通信混合动力系统蜂窝网络节能资源利用率非合作博弈

Virtual Network Embedding Algorithm for Load Balance with Various Requests

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Chinese Journal of Electronics 2014年第2期23卷 382-387页

作者： WANG Li qu hua ZHAO Jihong School of Electronic and Information Engineering Xi'an Jiaotong University School of Communication and Information Engineering Xi'an University of Posts and Telecommunications

Virtual network embedding(VNE) is a crucial technology for network virtualization to allocate network resource. Virtual network request in which node and link resource have great disparity will lead to unbalanced resource distribution and lower acceptance ratio of virtual network requests. In this paper, we provide a virtual network embedding algorithm for load balance with various requests. It maps virtual nodes to substrate nodes of which node link residual resource ratio is closest to that of virtual nodes, and then maps the virtual link to physical path using shortest path first algorithm with the link node residual resource ratio constraint. Simulation shows that the provided algorithm can get higher acceptance ratio and network resource utilization for load balance.

关键词： Virtual network embedding Load balance Heuristic algorithm Node mapping Link mapping

Energy-Efficient Outage Capacity in Sensing-Based Spectrum Sharing Cognitive Radio Networks

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Chinese Journal of Electronics 2018年第6期27卷 1271-1276页

Energy efficiency(EE) is an important metric for a Cognitive radio network(CRN). We focus on the EE maximization problem in a sensing-based spectrum sharing CRN for delay-sensitive applications. With the aid of one-dimension exhaustive search, fractional programming and Lagrange duality method, two energy-efficient optimal sensing time and power allocation policies are derived with the consideration of Average/Peak transmit power(ATP/PTP) constraints and Average interference power(AIP) constraints, respectively. Simulation results show that the proposed policies can achieve higher EE compared to the conventional spectrum sharing schemes.

关键词： Cognitive radio network(CRN) Energy efficiency(EE) Sensing-based spectrum sharing Power allocation

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基于锁模光学频率梳的高速数据传输

物理学报 2024年第4期73卷 178-185页

作者：刘琪华梅佳雪王金栋张福民曲兴华天津大学精密测试技术及仪器全国重点实验室天津300072 重庆大学光电技术及系统教育部重点实验室重庆400044

大数据时代网络数据流量的爆炸式增长给通信系统的容量和数据传输速率带来极大的挑战.本文基于锁模光学频率梳的宽光谱范围和高相位相干性提出了一种高频正交幅度调制信号生成方法,通过电光调制器对光学频率梳进行幅度相位整形并下变频... 详细信息

大数据时代网络数据流量的爆炸式增长给通信系统的容量和数据传输速率带来极大的挑战.本文基于锁模光学频率梳的宽光谱范围和高相位相干性提出了一种高频正交幅度调制信号生成方法,通过电光调制器对光学频率梳进行幅度相位整形并下变频至射频域,生成携带编码信息的高速、高阶、低相位噪声的调制信号,再结合锁模光学频率梳窄线宽、多波长的特性,仅使用单个激光器即可实现基于波分复用技术的大规模并行高速通信.仿真验证了该方案的可行性,随后在100 m的自由空间光链路中使用光子微波信号进行16元正交幅度调制通信实验,实现了误码率低于10^(–6)的14 Gbit/s数据传输.

关键词：锁模光学频率梳微波光子学空间光通信正交幅度调制