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Experiments and simulation on the overall DMG of long-haul cascade FM-EDFA systems

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Chinese Optics Letters 2024年第4期22卷 53-59页

作者：江歆睿武保剑严伟文峰邱昆 Key Laboratory of Optical Fiber Sensing and Communications Ministry of EducationUniversity of Electronic Science and Technology of ChinaChengdu 611731China

All-fiber few-mode erbium-doped fiber amplifiers(FM-EDFAs) with isolation and wavelength division multiplexers(IWDMs)have been developed to enable flexible pumping in different directions. The FM-EDFA can achieve >30 d B modal gain with<0.3 d B differential modal gain(DMG). We experimentally simulate the DMG performance of a cascade FM-EDFA system using the equivalent spectrum method. The overall DMG reaches 1.84 d B after 10-stage amplification. We also build a recirculating loop to simulate the system, and the developed FM-EDFA can support transmission up to 3270 km within a 2 d B overall DMG by optimizing the few-mode fiber length in the loop.

关键词： mode division multiplexing few-mode erbium-doped fiber amplifier gain equalization

NT⁃pro BNP、ET、UⅡ在妊娠期高血压Ⅰ~Ⅱ期眼底病变预测及病情评估中的应用评价

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中国计划生育和妇产科 2024年第2期16卷 92-95,F0004页

作者：吴葆健焦蕊丽北京市垂杨柳医院眼科北京100022 北京市朝阳区妇幼保健院生殖调节科北京100026

目的探讨N端⁃脑钠肽前体(N⁃terminal pro⁃brain natriuretic peptide,NT⁃pro BNP)、内皮素(endothelin,ET)、尾加压素Ⅱ(urotensinⅡ,UⅡ)在妊娠期高血压Ⅰ~Ⅱ期眼底病变预测及病情评估中的应用效果。方法选取2019年2月至2022年2月北京市垂杨柳医院198例妊娠期高血压患者作为观察组,有眼底病变110例,无眼底病变88例,另纳入86例正常孕妇作为对照组。比较两组血清NT⁃pro BNP、ET、UⅡ表达、最佳矫正视力(best corrected visual acuity,BCVA)、视敏度,Spearman相关系数分析各指标间关系,绘制受试者工作特征曲线(receiver operating characteristic curve,ROC)及曲线下面积分析血清各指标预测效能。结果观察组有眼底病变患者血清NT⁃pro BNP、ET、UⅡ水平高于无眼底病变患者及对照组,且无眼底病变患者高于对照组(P<0.05);Ⅰ期眼底病变患者血清NT⁃pro BNP、ET、UⅡ水平低于Ⅱ期眼底病变患者,BCVA、视敏度高于Ⅱ期眼底病变(P<0.05);Spearman相关系数显示,妊娠期高血压患者眼底病变程度与NT⁃pro BNP、ET、UⅡ呈正相关,与BCVA、视敏度呈负相关,且BCVA、视敏度与NT⁃pro BNP、ET、UⅡ均呈负相关(P<0.05);ROC曲线显示,三者联合预测妊娠期高血压眼底病变价值优于单一预测。结论妊娠期高血压眼底病变患者血清NT⁃pro BNP、ET、UⅡ水平与病情程度、BCVA、视敏度相关,联合检测有助于提高妊娠期高血压眼底病变预测价值。

关键词：妊娠期高血压眼底病变 N端⁃脑钠肽前体内皮素尾加压素

Ground effects on magnetooptic Bragg cells

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Chinese Science Bulletin 2008年第18期53卷 2753-2757页

作者： WEN Feng wu baojian QIU Kun Key Laboratory of Broadband Optical Fiber Transmission and Communication Networks of the Ministry of Education of China University of Electronic Science and Technology of China Chengdu 610054 China

Propagation equation of magnetostatic waves in an arbitrarily magnetized yttrium-iron-garnet/gadolinium- gallium-garnet waveguide coated with perfect metal planes is obtained using the method of the surface magnetic permeability. And ground effects on magnetooptic Bragg cells are investigated with the magnetooptic coupled-mode theory. Theoretical analysis indicates that, diffraction efficiency of guided optical waves can be improved by adjusting the spacing of the metal plane from the ferrite film, and ground effects on the diffraction efficiency will be enhanced using an appropriately tilted bias magnetic field. In the metal clad waveguide system, the magnetostatic wave frequency at which the diffraction efficiency peak is obtained corresponds to the "zero-dispersion" point. Performance of RF spectrum analyzers in this system can also be improved by comparing with the case of the sandwich waveguide. Therefore, magnetooptic Bragg cells with the metal clad waveguide are potential applications to the microwave communication and optical signal processing.

关键词：地面效应静磁波磁光衍射

Traffic estimation based on long short-term memory neural network for mobile front-haul with XG-PON

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Chinese Optics Letters 2019年第7期17卷 23-28页

作者： Min Zhang Bo Xu Xiaoyun Li Yi Cai baojian wu Kun Qiu Key Laboratory of Optical Fiber Sensing and Communications Ministry of EducationUniversity of Electronic Science and Technology of ChinaChengdu 611731China Business School University of International Business and EconomicsBeijing 100029China

A novel predictive dynamic bandwidth allocation(DBA) method based on the long short-term memory(LSTM)neural network is proposed for a 10-gigabit-capable passive optical network in mobile front-haul(MFH) *** predicting the number of packets that arrive at the optical network unit buffer based on LSTM, the round-trip time delay in traditional DBAs can be eliminated to meet the strict latency requirement for MFH *** study shows that the LSTM neural network has better performance than feed-forward neural *** on extensive simulations, the proposed scheme is found to be able to achieve the latency requirement for MFH and outperforms the traditional DBAs in terms of delay, jitter, and packet loss ratio.

关键词： Traffic estimation long short-term memory neural network

Simulation model of magneto-optic fiber Bragg gratings and its applications in Sagnac interferometers

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Frontiers of Optoelectronics 2010年第4期3卷 359-363页

作者： Shijuan wu baojian wu Kun QIU Chongzhen LI Key Lab of Broadband Optical Fiber Transmission and Communication Networks of the Ministry of Education University of Electronic Science and Technology of China

According to the symmetry of transmission matrix for non-uniform magneto-optic fiber Bragg gratings(MFBGs), the simulation model of the non-uniform MFBGs with bidirectional injection of light has been presented for the Optisystem software. The simulation model is verified by comparing with the Matlab numeric results using the piecewise-uniform MFBG model. As an example, the polarization-dependent loss(PDL) of an MFBG-based Sagnac interferometer(MSI) is analyzed in detail. Simulation results indicate that the magnetic field sensitivity of the MSI system can be improved by optimizing the coupling coefficient of the coupler, and the maximum of peak PDL is up to three times that of the single MFBG structure. The simulation model proposed in the paper is useful for the design of MFBG-based optical information devices.

关键词： magneto-optic fiber Bragg grating (MFBG) Optisystem simulation polarization-dependent loss (PDL) Sagnac interferometer (SI)

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牛蒡提取物安全性的初步研究

医学动物防制 2024年第6期40卷 596-601,605页

作者：李晓华聂文强吴宝剑李军涛李文学杨光宇广东药科大学附属第一医院全科医学科广东广州510440 暨南大学药学院广州市疾病预防控制中心毒理学检验部

目的以牛蒡提取物为研究对象,初步对牛蒡的安全性进行毒理学评价。方法根据卫生部《保健食品检验与评价技术规范》(2003年版)要求,选择急性经口毒性试验、鼠伤寒沙门菌回复突变(Salmonella typhimurium/reverse mutation,Ames)试验、小... 详细信息

目的以牛蒡提取物为研究对象,初步对牛蒡的安全性进行毒理学评价。方法根据卫生部《保健食品检验与评价技术规范》(2003年版)要求,选择急性经口毒性试验、鼠伤寒沙门菌回复突变(Salmonella typhimurium/reverse mutation,Ames)试验、小鼠骨髓细胞微核试验、小鼠精子畸形试验和30d灌胃试验对牛蒡提取物进行毒性评价。结果急性经口毒性试验动物灌胃后未见明显中毒反应,牛蒡提取物小鼠急性经口半数致死量(median lethal dose,LD50)>15.0g/kg·bw,毒性分级属无毒级;Ames试验牛蒡提取物回变菌落数未超过溶剂对照的2倍且无剂量-反应关系,提示牛蒡提取物致突变试验结果为阴性;牛蒡提取物各剂量组骨髓细胞微核率和精子畸形率与溶剂对照组比较,差异无统计学意义(χ^(2)=7.035、4.216,P>0.05);牛蒡提取物大鼠30d经口灌胃试验期间,动物生长发育良好,体质量、食物利用率、血液学、血液生化学、脏器系数和组织病理学等相关指标均未见明显特异性毒理学变化,最大未观察到有害作用剂量(no-observed-adverse-effect level,NOAEL)8.0g/kg·bw。结论牛蒡提取物急性毒性分级属无毒级,无遗传毒性,在本研究实验条件和试验剂量下,可初步认定其作为中药材及保健食品是安全的。

关键词：牛蒡提取物保健食品中药材毒性研究安全性评价

Magnetic tunability of fiber optical parametric oscillators with optical clock extraction

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Frontiers of Optoelectronics 2011年第3期4卷 325-329页

作者： Tianzhi LE baojian wu Feng WEN Kun QIU Key Lab of Broadband Optical Fiber Transmission and Communication Networks of the Ministry of Education University of Electronic Science and Technology of China

A 10 Gb/s all-optical clock extraction based on magnetically controllable fiber optical parametric oscillator(MC-FOPO) is demonstrated. The operation properties of the magnetic control unit, composed of a solenoid and a magneto-optic crystal of high Verdet constant, are experimentally investigated. By adjusting the drive current of the solenoid, the magneto-optic crystal unit may serve as a tunable optical fiber delay line with polarization control to some extent. The experimental results show that the MC-FOPO is capable of repetitively magnetic tunability desirable for all-optical clock recovery.

关键词： fiber optical parametric oscillator (FOPO) clock extraction magnetic control

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静磁表面波对高斯光脉冲的衍射特性研究

光学学报 2009年第7期29卷 1784-1789页

作者：高翔武保剑电子科技大学宽带光纤传输与通信网技术教育部重点实验室四川成都610054

研究了磁光薄膜波导中线性啁啾高斯光脉冲与单频连续静磁波共线作用,给出了水平磁化时基于静磁表面波的磁光耦合方程。分别采用解析法和数值法计算了1310 nm和1550 nm两种光波长入射时衍射光的压缩特性,两种求解方法得到的结果一致。计... 详细信息

研究了磁光薄膜波导中线性啁啾高斯光脉冲与单频连续静磁波共线作用,给出了水平磁化时基于静磁表面波的磁光耦合方程。分别采用解析法和数值法计算了1310 nm和1550 nm两种光波长入射时衍射光的压缩特性,两种求解方法得到的结果一致。计算表明,衍射光脉冲的半峰全宽(FWHM)随相位失配因子的频率变化率和啁啾系数的增大而减小;在给定的计算参数下,与1310 nm波长对应的衍射光脉冲具有较大的峰值强度,但1550 nm波长输入时可以获得更窄的衍射光脉冲,因而1550 nm光脉冲更适于作为磁光脉冲压缩的脉冲源。文章还分析了磁损耗对衍射光脉冲的光强和输出脉宽的影响,对于普通的磁光薄膜,损耗基本上不影响光脉冲压缩效果。

关键词：光通信磁光信号处理光脉冲压缩磁光Bragg衍射效应静磁表面波磁损耗

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垂直不均匀磁场中静磁波的传播特性

电子学报 1999年第9期27卷 32-34页

作者：武保剑刘公强上海交通大学应用物理系上海200030

本文理论分析了垂直不均匀磁场作用下磁性薄膜中静磁波的传播特性，具体计算了抛物线分布的不均匀磁场对静磁对表镣波振幅的影响．计算表明，在适当分布的不均匀场作用下，与均匀磁场情形相比，波导中传播的静磁波振幅有所增加。

关键词：不均匀磁场静磁波磁性薄膜传播特性