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基于MIMO神经网络均衡的16QAM模分-波分复用相干传输系统

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光学学报 2024年第3期44卷 38-45页

作者：张尧王晨桑博涵张宇王心怡周雯余建军复旦大学信息科学与工程学院上海200433

提出了一种基于神经网络的多输入多输出(MIMO)均衡器,并在大容量模分-波分复用通信系统中进行了实验验证。该系统基于6模掺铒光纤放大器实现了16通道波分复用双极化48 Gbaud 16阶正交振幅调制(16QAM),在LP01、LP02、LP11a、LP11b、LP21a... 详细信息

提出了一种基于神经网络的多输入多输出(MIMO)均衡器,并在大容量模分-波分复用通信系统中进行了实验验证。该系统基于6模掺铒光纤放大器实现了16通道波分复用双极化48 Gbaud 16阶正交振幅调制(16QAM),在LP01、LP02、LP11a、LP11b、LP21a、LP21b六种模式上传输了100 km少模光纤(FMF)。为降低非线性的影响,在接收端数字信号处理中,采用基于多标签技术的MIMO神经网络均衡器,能够显著提升系统性能。实验结果表明,经100 km的FMF传输,MIMO神经网络均衡器的强大性能使得系统的比特误码率能满足15%软判决前项纠错阈值要求。

关键词：光纤光学光纤通信模分复用波分复用神经网络均衡

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基于熵值法的出版上市企业研发能力评价

科技和产业 2024年第2期24卷 70-76页

作者：桑广成焦建玲桑博涵河北出版传媒集团有限责任公司石家庄050061 河北经贸大学会计学院石家庄050061 复旦大学信息科学与工程学院上海200438

随着出版业融合发展步伐的加快,研发和创新驱动成为出版业提升内生发展动力的利器,并将深入赋能文化强国和数字中国建设。为客观评价出版企业研发能力水平,利用熵值法构建评价指标体系对我国17家上市出版企业研发能力进行测度。通过分... 详细信息

随着出版业融合发展步伐的加快,研发和创新驱动成为出版业提升内生发展动力的利器,并将深入赋能文化强国和数字中国建设。为客观评价出版企业研发能力水平,利用熵值法构建评价指标体系对我国17家上市出版企业研发能力进行测度。通过分析评价结果,发现出版企业存在研发投入不足、投入产出率低、会计核算不统一、技术标准不统一等问题,并针对这些问题提出相关建议,以期助力我国出版企业更好地进行研发创新,实现高质量发展。

关键词：出版企业研发能力评价体系熵值法

基于LSTM非线性均衡的64QAM波分模分复用通信相干传输系统

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中国激光 2024年第17期51卷 206-212页

作者：张尧桑博涵王晨龙健宇王凯辉周雯刘博余建军复旦大学信息科学与工程学院专用集成电路与系统国家重点实验室上海200433

为满足新兴应用对通信能力日益增长的要求,提出一种基于长短时记忆网络(LSTM)的非线性均衡器,并演示一个长距离大容量波分模分复用(MDM-WDM)通信系统。该实验在650 km的少模光纤(FMF)上,实现80通道波分复用双极化48 GBaud 64QAM信号在LP... 详细信息

为满足新兴应用对通信能力日益增长的要求,提出一种基于长短时记忆网络(LSTM)的非线性均衡器,并演示一个长距离大容量波分模分复用(MDM-WDM)通信系统。该实验在650 km的少模光纤(FMF)上,实现80通道波分复用双极化48 GBaud 64QAM信号在LP11a、LP11b、LP21a、LP21b四种模式上传输。为减小系统中非线性效应的影响,在接收端数字信号处理(DSP)中,采用基于LSTM的非线性均衡技术,显著提升系统性能。实验结果表明,经650 km的少模光纤传输,系统的比特误码率(BER)能满足25%软判决前项纠错阈值(SD-FEC),净速率达到147.4 Tbit/s,属于国内领先水平。

关键词：光纤通信模分复用波分复用少模光纤神经网络均衡

双模式80波分通道1000km少模光纤传输

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中国激光 2023年第23期50卷 169-176页

作者：郑天启王晨王凯辉丁俊杰朱博文桑博涵周雯沈磊张磊王瑞春闫长鹍余建军复旦大学通信与信息工程学院通信科学与工程系上海200433 长飞光纤光缆股份有限公司湖北武汉430073

为了解决急剧提升的通信系统容量需求与长距离传输等问题,通过实验验证了超大容量的少模光纤传输。在超大容量需求的背景下,同时使用波分复用、模分复用、偏振复用三种复用技术进行信号传输,凭借自研的低损耗六模渐变型光纤(各模式衰减... 详细信息

为了解决急剧提升的通信系统容量需求与长距离传输等问题,通过实验验证了超大容量的少模光纤传输。在超大容量需求的背景下,同时使用波分复用、模分复用、偏振复用三种复用技术进行信号传输,凭借自研的低损耗六模渐变型光纤(各模式衰减约为0.2 dB/km),实现了覆盖C波段共80个通道,每个通道双模双偏振信号的1000 km传输。考虑到超长距离传输带来的色散和双模双偏振带来的串扰,在进行接收端离线数字信号处理(DSP)时首先使用频域色散补偿算法进行色散补偿,并在下采样和时钟恢复后联合利用多输入多输出-频域最小均方算法(MIMO-FDLMS)和多输入多输出-时域最小均方算法(MIMO-TDLMS)进行信道均衡和色散补偿。在28%冗余的低密度奇偶校验(LDPC)信道编码软判决前向纠错(SD-FEC)阈值5.2×10^(-2)条件下,实现了总的线传输速率40.96 Tbit/s,净速率高达32 Tbit/s。

关键词：光通信波分复用模分复用偏振复用长距离传输超大容量传输

基于外差相干探测的极化复用16QAM信号双模式1000 km少模光纤传输系统

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中国激光 2023年第19期50卷 143-148页

作者：卞诚真王晨桑博涵王凯辉丁俊杰朱博文沈磊张磊王瑞春闫长鹍刘博余建军复旦大学信息科学与工程学院通信科学与工程系上海200433 长飞光纤光缆股份有限公司湖北武汉430073 南京信息工程大学物理与光电工程学院江苏南京210044

为了解决通信容量不足以及非线性损伤问题,基于正交相位(IQ)调制外差相干探测,利用极化复用技术、模分复用技术以及先进的数字处理算法,搭建了单通道模分复用少模光纤传输系统,并成功实现了波特率为32 Gbaud的16正交振幅调制(QAM)信号... 详细信息

为了解决通信容量不足以及非线性损伤问题,基于正交相位(IQ)调制外差相干探测,利用极化复用技术、模分复用技术以及先进的数字处理算法,搭建了单通道模分复用少模光纤传输系统,并成功实现了波特率为32 Gbaud的16正交振幅调制(QAM)信号在两个兼并模LP11a和LP11b模式下的1000 km传输。使用时域和频域多输入多输出最小均方(MIMO-LMS)算法进行均衡处理后,误码率(BER)低于软判决前向纠错(SD-FEC)的阈值(5.2×10^(-2))。

关键词：光通信光纤通信模分复用少模光纤极化复用长距离传输

Correlative Mn-Co catalyst excels Pt in oxygen reduction reaction of quasi-solid-state zinc-air batteries

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Nano Research 2024年第5期17卷 4118-4124页

作者： Tingting Wang Jincheng Huang Wei sang Cai Zhou bohan Zhang Wei Zhu Kang Du Zongkui Kou Shengxiang Wang School of Mathematical and Physical Sciences Wuhan Textile UniversityWuhan 430200China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Zn-air batteries(ZABs)as a class of promising energy storage setups are generally powered by efficient and robust catalysts at the oxygen-involving *** the existing non-noble catalysts have outperformed noble Pt benchmark in the alkaline liquid-state ZABs,to the best of our knowledge few have excelled Pt in quasi-solid-state(QSS)***,we found that an integrated Mn-Co cathode derived from the bimetallic Mn/Co metal organic frameworks generates a 1.4-fold greater power density in the QSS ZABs than a Pt cathode while its power density in liquid-state ZABs is only 0.8-fold of the ***,such Mn-Co catalyst delivers high-rate oxygen reduction reaction(ORR)capability with half-wave potential of 0.84 *** in-depth characterizations and analyses have demonstrated that the Co and Mn species show the specific affinity towards H_(2)O and O_(2),respectively,synergizing the ORR process in the water-deficient environment of QSS *** work has enlightened the rational design of non-noble metal catalysts to improve the power density of QSS ZABs.

关键词： non-noble metal catalysts zinc-air battery quasi-solid-state synergistic effect

An Improved Method for Web Text Affective Cognition Computing Based on Knowledge Graph

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Computers, Materials & Continua 2019年第4期59卷 1-14页

作者： bohan Niu Yongfeng Huang Department of Electrical Engineering Columbia UniversityNew YorkNY 10027USA Department of Electronic Engineering Tsinghua UniversityBeijing100084China

The goal of research on the topics such as sentiment analysis and cognition is to analyze the opinions,emotions,evaluations and attitudes that people hold about the entities and their attributes from the *** word level affective cognition becomes an important topic in sentiment *** the(attribute,opinion word)binary relationship by word segmentation and dependency parsing,and labeling those by existing emotional dictionary combined with webpage information and manual annotation,this paper constitutes a binary relationship knowledge *** using knowledge embedding method,embedding each element in(attribute,opinion,opinion word)as a word vector into the Knowledge Graph by TransG,and defining an algorithm to distinguish the opinion between the attribute word vector and the opinion word *** with traditional method,this engine has the advantages of high processing speed and low occupancy,which makes up the time-costing and high calculating complexity in the former methods.

关键词： Affective cognition fine-grained knowledge representation knowledge graph

Aging Precipitation Behavior and Mechanical Properties of Inconel 617 Superalloy

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Acta Metallurgica Sinica(English Letters) 2013年第3期26卷 307-312页

作者： Yan GUO bohan WANG Shufang HOU Materials Department Xi'an Thermal Power Research Institute Co.Ltd.

Aging precipitation behavior and mechanical properties of Inconel 617 superalloy aged at 760℃ for up to 10000 h were investigated. The results showed that the precipitates of the aged alloy are M23C6 and M6C carbides and γ phase. The carbide particles precipitated both at the grain boundaries and within grains, and the γ phase particles were situated at intragranular sites in the process of aging. The carbide particles were discontinuously dispersed at grain boundaries after aging for 3000 h, while after aged for 5000 h the carbide particles are merged. The precipitates inside grains remained stable even after aging for 10000 h. The hardness was increased for the alloy aged for 300 h up to 3000 h, which was resulted primarily from the precipitation of carbides as discrete particles both at the grain boundaries and inside grains. Small quantity γ precipitates were formed inside grains, to some extent, which contributed to an enhanced hardness. However, a decrease of the hardness was observed after aging for 5000 h. A significant drop in toughness of the alloy aged for 300 h was attributed to the reduction of the bonding interface strength when carbides precipitated at grain boundaries. Thereafter, the toughness decreased slowly with the prolonged aging time. The high temperature tensile properties of the aged alloy are rather stable even aged for 300-3000 h.

关键词： Inconel 617 Superalloy Aging Precipitate Mechanical properties

Bioinspired nanocomposites with self-adaptive mechanical properties

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Nano Research 2024年第2期17卷 633-648页

作者： Grant Kitchen bohan Sun Sung Hoon Kang 13400 N Charles St Department of Materials Science and EngineeringJohns Hopkins UniversityBaltimore 21218USA 23400 N Charles St Department of Mechanical EngineeringJohns Hopkins UniversityBaltimore 21218USA 33400 N Charles St Hopkins Extreme Materials InstituteJohns Hopkins UniversityBaltimore 21218USA

Conventional synthetic materials have fixed mechanical properties and suffer defects,damage,and degradation over *** makes them unable to adapt to changing environments and leads to limited ***,self-adaptive materials inspired by natural materials have emerged as a solution to address these *** the ability to change their mechanical properties based on changing mechanical environments,repairing defects,and maintaining their mechanical properties,these materials can lead to improved performance while decreasing *** this review,we explore self-adaptive phenomena found in nature that have inspired the development of synthetic self-adaptive materials,and the mechanisms that have been employed to create the next generation of *** potential applications of these materials,the challenges that existing approaches face,and future research opportunities are also discussed.

关键词： nanocomposites self-adaptive materials bioinspired materials force-activated resilience