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Environmental Information-Aided Electromagnetic Propagation Testbed for Maritime Communication

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China Communications 2023年第3期20卷 302-315页

作者： Ting Zhou Yuzhen Wang Bilian xu tianheng xu Xiaoming Tao Honglin Hu Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of ScienceBeijing 100049China School of Microelectronics Shanghai UniversityShanghai 200444China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

Maritime channel modeling can be affected by some key time-varying environmental *** ducting effect is one of the thorniest factors since it causes anomalous propagation enhancement and severe co-channel ***,the atmospheric attenuation is much more severe in the ocean environment,resulting in shorter coverage distance and more link *** this paper,we propose an environmental information-aided electromagnetic propagation *** is based on complex refractivity estimation and improved parabolic equation propagation model,taking into account both ducting effect and atmospheric attenuation.A large-scale temporal and spatial propagation measurement was conducted with meteorological *** consider practical path loss and ducting conditions to verify the testbed feasibility in these long-distance radio *** simulation results are in good agreement with the measured data,which further reveal the basic temporal and spatial distribution of ducting effect at 3.5 GHz band.

关键词： broadband maritime communication maritime channel ducting effect electromagnetic propagation testbed propagation measurement atmospheric attenuation path loss

Fragmental Weight-Conservation Combining Scheme for Statistical Signal Transmissions under Fast Time-Varying Channels

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China Communications 2020年第1期17卷 118-128页

作者： Xingwei Wang Ting Zhou tianheng xu Songlin Feng Honglin Hu Yanliang Jin School of Communication and Information Engineering Shanghai UniversityShanghai 200444China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

Statistical Signal Transmission(SST)is a technique based on orthogonal frequency-division multiplexing(OFDM)and adopts cyclostationary features,which can transmit extra information without additional ***,the more complicated environment in 5G communication systems,especially the fast time-varying scenarios,will dramatically degrade the performance of the *** this paper,we propose a fragmental weight-conservation combining(FWCC)scheme for SST,to overcome its performance degradation under fast time-varying *** proposed FWCC scheme consists of three phases:1、incise the received OFDM stream into pieces;2、endue different weights for fine and contaminated pieces,respectively;3、combine cyclic autocorrelation function energies of all the pieces;and 4、compute the final feature and demodulate data of *** these procedures above,the detection accuracy of SST will be theoretically refined under fast time-varying *** an inference is confirmed through numerical results in this *** is demonstrated that the BER performance of proposed scheme outperforms that of the original scheme both in ideal channel estimation conditions and in imperfect channel estimation *** addition,we also find the experiential optimal weight distribution strategy for the proposed FWCC scheme,which facilitates practical applications.

关键词： Cyclostationary features statistical signal transmission(SST) weight conservation time-varying channels

K-shell excitation dielectronic recombination resonance strengths of highly charged Helike to O-like Xe ions

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Plasma Science and Technology 2018年第7期20卷 72-76页

作者： tianheng xu Gang XIONG Jun XIAO Yang YANG Roger HUTTON Yarning ZOU Ke YAO Shanghai EBIT Laboratory Institute of Modem Physicsand Key Laboratory of Nuclear Physics and Ion-beam Application（MOE）Fudan UniversityShanghai 200433People＇s Republic of China Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900People＇s Republic of China

Dielectronic recombination is an important process in high temperature plasmas. In the present work, the KLn （n=L, M, N and O） DR resonance strengths of He-like to O-like xenon ions are measured at the Shanghai electron beam ion trap using a fast electron beam energy scanning method. The experiment uncertainty reaches about 6% with significant improvement of statistics. A relativistic configuration interaction calculation is also made. Theoretical results agree with the experiment results within 15% in most cases.

关键词： dielectronic recombination (DR) electron ion beam trap (EBIT)

Nucleus-Nucleus Interaction Potential Energy of Di-nuclear System

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IMP & HIRFL Annual Report 2004年 50-51页

作者： Jia Fei, xu Hushan, Huang tianheng, xu Huagen, Chen Ruofu and Li Junqing

The nucleus-nucleus interaction potential is very important for studying the formation and the evolution of the DNS. The potential energy of the DNS can be written as: U(A1,A2,R)=B1+B2-B12+

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Nucleus-Nucleus Interaction Potential Energy of Di-nuclear System

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近代物理研究所和兰州重离子加速器实验室年报：英文版 2004年第1期 29-30页

作者： Jia Fei, xu Hushan, Huang tianheng, xu Huagen, Chen Ruofu and Li Junqing

The nucleus-nucleus interaction potential is very important for studying the formation and the evolution of the DNS. The potential energy of the DNS can be written as: U(A1,A2,R)

关键词：相互作用势能双核系统核基因原子核 DNS 联合国

Fragmental Weight-Conservation Combining Scheme for Statistical Signal Transmissions under Fast Time-Varying Channels

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Fragmental Weight-Conservation Combining Scheme for Statisti...

基于VRS-DEA模型与Malmquist指数的工业园区土地利用效率评价——以长三角城市群16个工业园区为例

2018中国信息通信大会(CICC2018)

作者： Xingwei Wang tianheng xu Ting Zhou Honglin Hu

Statistical Signal Transmission（SST）is a technique based on orthogonal frequency-division multiplexing（OFDM）and adopts cyclostationary features,which can transmit extra information without additional *** this paper,we propose a fragmental weight-conservation combining（FWCC）scheme for SST *** proposed FWCC scheme consists of three phases:1)incise the received OFDM stream into pieces;2)endue different weights for fine and contaminated pieces,respectively;3)combine cyclic autocorrelation function energies of all the pieces;and 4)compute the final feature and demodulate data of *** these procedures above,the detection accuracy of SST will be theoretically refined under fast time-varying *** an inference is confirmed through numerical results in this *** is demonstrated that the BER performance of proposed scheme outperforms that of the original scheme both in ideal channel estimation conditions and in imperfect channel estimation *** addition,we also find the experiential optimal weight distribution strategy for the proposed FWCC scheme,which facilitates practical applications.

关键词： cyclostationary features statistical signal transmission(SST) weight conservation time-varying channels

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资源科学 2017年第6期39卷 1026-1036页

作者：施建刚徐天珩同济大学经济与管理学院上海200092

针对长三角城市群工业园区动态效率研究不足的问题,本文选取16个国家级工业园区为研究样本,基于单位土地面积投入产出指标,利用VRS-DEA模型与Malmquist指数,对2010-2014年长三角城市群工业园区土地利用效率情况进行分解动态评价,并定量... 详细信息

针对长三角城市群工业园区动态效率研究不足的问题,本文选取16个国家级工业园区为研究样本,基于单位土地面积投入产出指标,利用VRS-DEA模型与Malmquist指数,对2010-2014年长三角城市群工业园区土地利用效率情况进行分解动态评价,并定量分析其投入产出要素改善潜力。研究发现:(1)长三角城市群工业园区在5年间的土地利用综合效率均值为0.600,仅2个工业园区在5年中均DEA有效,且地域差异明显,从效率分解变化来看,规模效率>纯技术效率>技术效率;(2)从动态时间序列看,5年间工业园区Malmquist生产率指数整体呈增长趋势,技术效率变化贡献最大、纯技术效率变化贡献其次,而技术进步变化拖累,说明技术改进的薄弱是影响工业园区土地利用效率的核心因素;(3)通过对5年间土地利用DEA无效工业园区的要素投入产出改善途径与潜力分析,发现以税收收入与工业产值不足为核心的有效产出不足为各工业园区DEA无效的主要原因,长三角城市群各工业园区应在保持投入规模有效性的基础上,提升工业技术效率,同时完善转型升级期间工业园区招商引资与税收制度。

关键词： VRS-DEA模型 Malmquist指数工业园区土地利用效率长三角城市群

首周期先驱体溶液浓度对PIP法制备3D-C_f/Si-O-C的影响

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稀有金属材料与工程 2008年第A01期37卷 600-603页

作者：徐天恒陈朝辉马青松国防科技大学新型陶瓷纤维及其复合材料重点实验室湖南长沙410073

以三维碳纤维编织物和硅树脂(SR249)为原料,采用先驱体转化法(PIP)制备了3D-C_f/Si-O-C材料,考察了首周期先驱体溶液浓度对其力学性能的影响。结果表明:首周期浸渍先驱体溶液的浓度不同会导致3D-C_f/Si-O-C复合材料中气孔大小及分布的... 详细信息

以三维碳纤维编织物和硅树脂(SR249)为原料,采用先驱体转化法(PIP)制备了3D-C_f/Si-O-C材料,考察了首周期先驱体溶液浓度对其力学性能的影响。结果表明:首周期浸渍先驱体溶液的浓度不同会导致3D-C_f/Si-O-C复合材料中气孔大小及分布的不同而对力学性能产生较大影响,随首周期先驱体溶液浓度的增大,3D-C_f/Si-O-C复合材料力学性能先降低后提高。首周期采用SR249/xylene体积比为0.5∶1先驱体溶液制备的3D-C_f/Si-O-C复合材料力学性能和气孔率都处于极小值,其弯曲强度为247 MPa,断裂韧性为9.6 MPa·m^(1/2),气孔率为10.8%。

关键词：硅树脂先驱体转化先驱体溶液浓度陶瓷基复合材料

一种NOMA系统中的反馈深度神经网络检测算法

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电讯技术 2023年第5期63卷 611-617页

作者：王奕峰周婷徐天衡中国科学院大学微电子学院北京100049 中国科学院上海高等研究院上海201210

在上行非正交多址(Non-orthogonal Multiple Access,NOMA)系统中,针对传统基于串行干扰消除(Successive Interference Cancellation,SIC)检测存在同个时频块内用户间干扰的问题,提出了一种新型的NOMA检测算法。通过将SIC检测的反馈消除... 详细信息

在上行非正交多址(Non-orthogonal Multiple Access,NOMA)系统中,针对传统基于串行干扰消除(Successive Interference Cancellation,SIC)检测存在同个时频块内用户间干扰的问题,提出了一种新型的NOMA检测算法。通过将SIC检测的反馈消除结构和深度神经网络结合起来,设计出了一种新型的反馈深度神经网络(Feedback Deep Neural Network,FDNN)结构。FDNN模型分为两个模块,检测模块通过深度神经网络实现非线性检测,反馈模块通过权重矩阵重构信号并消除用户干扰。通过重复检测和反馈过程,FDNN依次检测出各个用户的符号,并达到了良好的性能。仿真结果表明FDNN检测算法相较于SIC检测具有更低的误符号率和误比特率,并验证了其具有更良好的抗用户间干扰的性能。

关键词：非正交多址接入串行干扰消除深度神经网络非线性检测