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Demonstration of 5.12-Tbps THz-over-fiber transmission in 80 channel WDM system

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Science China(Technological Sciences) 2023年第5期66卷 1480-1482页

作者： ZHAO Li long jianyu DING JunJie YU JianJun Department of Communication Science and Engineering Fudan UniversityShanghai 200433China

The arrival of 5G and the incoming 6G era demand ultralarge-capacity and long-distance transmission for wired and wireless *** adequate bandwidth,the terahertz(THz)-wave(0.3 THz–10 THz)is very promising and has the ability to carry ultra-high-speed signals[1–7].However,there has been little research on THz-over-fiber technology until ***,it is extremely competitive and challenging to achieve the potential THz-over-fiber communication for the 6G technology in the near future.

关键词： fiber WDM carry

Sparse Autoencoder-based Multi-head Deep Neural Networks for Machinery Fault Diagnostics with Detection of Novelties

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 146-157页

作者： Zhe Yang Dejan Gjorgjevikj jianyu long Yanyang Zi Shaohui Zhang Chuan Li School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Faculty of Computer Science and Engineering Ss.Cyril and Methodius UniversitySkopjeMacedonia

Supervised fault diagnosis typically assumes that all the types of machinery failures are ***,in practice unknown types of defect,i.e.,novelties,may occur,whose detection is a challenging *** this paper,a novel fault diagnostic method is developed for both diagnostics and detection of *** this end,a sparse autoencoder-based multi-head Deep Neural Network(DNN)is presented to jointly learn a shared encoding representation for both unsupervised reconstruction and supervised classification of the monitoring *** detection of novelties is based on the reconstruction ***,the computational burden is reduced by directly training the multi-head DNN with rectified linear unit activation function,instead of performing the pre-training and fine-tuning phases required for classical *** addressed method is applied to a benchmark bearing case study and to experimental data acquired from a delta 3D *** results show that its performance is satisfactory both in detection of novelties and fault diagnosis,outperforming other state-of-the-art *** research proposes a novel fault diagnostics method which can not only diagnose the known type of defect,but also detect unknown types of defects.

关键词： Deep learning Fault diagnostics Novelty detection Multi-head deep neural network Sparse autoencoder

New Progress in Paleoearthquake Studies of the East Sertengshan Piedmont Fault, Inner Mongolia, China

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Journal of Earth Science 2018年第2期29卷 441-451页

作者： Zhongtai He Baoqi Ma jianyu long Jinyan Wang Hao Zhang Key Laboratory of Crustal Dynamics Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China Institute of Earthquake Engineering for Jiangsu Province Nanjing 210014 China

The two eastern segments of the Sertengshan piedmont fault have moved considerably since the Holocene. Several paleoseismic events have occurred along the fault since 30 ka BP. Pa- leoearthquake studies have been advanced by digging new trenches and combining the results with the findings of previous studies. Comprehensive analyses of the trenches revealed that 6 paleoseismic events have occurred on the Kuoluebulong segment since approximately 30 ka BP within the following successive time periods： 19.01-37.56, 18.73, 15.03-15.86, 10.96, 5.77-6.48, and 2.32 ka BP. The analyses also revealed that 6 paleoseismic events have occurred on the Dashetai segment since approximately 30 ka BP, and the successive occurrence times are 29.07, 19.12-28.23, 13.92-15.22, 9.38-9.83, 6.08--8.36, and 3.59 ka BP. The results indicate that quasi-periodic recurrences occurred along the two segments with an approximate 4 000 a mean recurrence interval. The consistent timing of the 6 events between the two segments indicates that the segments might conform to the cascade rupturing model between the two segments. As recorded by a large number of Chinese historical texts, the latest event on the Kuoluebulong segment is the historical M 8.0 earthquake occurred on November U, 7 BC.

关键词： active fault Sertengshan piedmont fault fault segmentation paleoearthquake.

High spectral efficiency 4-mode 400-km transmission using hybrid probabilistically and geometrically shaped 128QAM

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Science China(Technological Sciences) 2024年第5期67卷 1628-1630页

作者： DING JunJie YU JianJun WANG Chen long jianyu ZHU Min ZHANG Jiao Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China Key Laboratory for Information Science of Electromagnetic Waves(MoE) Fudan UniversityShanghai 200433China

Wavelength division multiplexing(WDM)and space division multiplexing(SDM)based on few-mode fiber(FMF)and multi-core fiber(MCF)have been vigorously developed to increase the transmission capacity of optical communication networks[1–5].However,the mode crosstalk generated in the mode division multiplexing(MDM)system causes the correlation between different mode signals,which seriously damages the transmission ***,an effective multiple-input-multiple-output(MIMO)time domain or frequency domain equalizer should be used to eliminate the crosstalk between different mode signals.

关键词： crosstalk fiber multiplexing

Co-Seismic Surface Rupture and Recurrence Interval of Large Earthquakes along Damaoyaba-Litang Segment of the Litang Fault on the Eastern Margin of the Tibetan Plateau in China

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Journal of Earth Science 2021年第5期32卷 1139-1151页

作者： Shiyuan Wang Rongjun Zhou Mingjian Liang Shao Liu Nina Liu jianyu long Sichuan Earthquake Agency^Chengdu 610041 China School of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The Litang fault is a left-lateral secondary shear zone in the Sichuan-Yunnan active block that accommodates the tectonic deformation associated with the eastward extrusion of the upper crust of the Tibetan Plateau. Based on 1 : 50 000 geological mapping of active faults, the Litang fault consists of three geometric segments, the Cuopuhu, Damaoyaba, and Litang segments, in the west of Litang, which are divided by the of Haizi Mountain uplift and the wide-angle bending and branching of the fault near Jinchanggou. This study also identifies the surface rupture of the A.D. 1890 earthquake, which is distributed intermittently along the ~28 km long Damaoyaba segments and ~25 km long Litang segments. The maximum horizontal displacement is 4.1 m along Damaoyaba segments, and 4 m along Litang segments. The rupture involves typical left-lateral shear movement. The two ruptures are divided by discontinuous segments or gaps that are ~18 km long;thus, the total surface rupture is approximately 71 km long. The estimated moment magnitude was M_(w)7.3±0.1. A comprehensive analysis of data obtained from 5 trenches excavated along the Damaoyaba and Litang segments and the trench data by Xu et al.(2005) identifies age constraints of the 4 most recent paleoseimic events occurred B.C. 1468±54–1340±25, B.C. 52±25–A.D. 76±47, A.D. 1115±90, and A.D. 1890, respectively. The recurrence intervals are 1 415±80, 1 104±104, and 775±90 a, which are consistent with quasi-periodic earthquake recurrence behavior. The average recurrence interval is 1 098±112 a.

关键词： Litang fault surface rupture active fault recurrence intervals paleoearthquake eastern Tibetan Plateau

时空约束下连铸车间天车调度的多目标建模与求解

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系统工程理论与实践 2017年第9期37卷 2373-2383页

作者：高小强李盼龙建宇郑忠重庆大学经济与工商管理学院重庆400044 重庆大学材料科学与工程学院重庆400045

针对钢厂炼钢-连铸车间天车调度的时空约束下NP难问题特点,考虑重钢包和空钢包吊运任务,以所有吊运任务等待被运输时间最短、总运输时间最短、天车之间负载时间差异最小为优化目标,按作业跨中多台天车执行吊运任务的时间空间约束、天车... 详细信息

针对钢厂炼钢-连铸车间天车调度的时空约束下NP难问题特点,考虑重钢包和空钢包吊运任务,以所有吊运任务等待被运输时间最短、总运输时间最短、天车之间负载时间差异最小为优化目标,按作业跨中多台天车执行吊运任务的时间空间约束、天车运行安全约束条件满足等为约束方程,建立了天车调度模型.设计了天车调度规则用于抽象表达其运行特征,即按吊运任务与天车的相对位置关系确定各天车与任务的匹配度,作为选择天车的指导;按天车状态及位置更新规则描述天车运行过程;按任务种类与预计起止时间先后确定吊运任务的优先级,作为天车运行过程中利用天车被动运输进行冲突消解的依据.设计了与模型特征相适应的改进遗传算法进行求解,采用某钢厂连铸跨的生产数据进行检验,通过与禁忌搜索法进行对比,证实了改进遗传算法的可行性和有效性,能够为生产过程中的天车调度提供指导.

关键词：天车调度时空约束多目标模型调度规则改进遗传算法

实验演示100 Gbaud Delta-Sigma调制信号O波段传输

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光学学报 2023年第20期43卷 67-73页

作者：杨雄伟魏怡龙健宇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

为了解决传输高阶正交幅度调制(QAM)信号时的非线性损伤问题,提出了一种基于Delta-Sigma调制(DSM)的高阶QAM传输系统。通过采用1-bit量化的DSM,成功将携带有高阶QAM的离散多音调制(DMT)信号量化编码为开关键控(OOK)信号,实现了高阶QAM... 详细信息

为了解决传输高阶正交幅度调制(QAM)信号时的非线性损伤问题,提出了一种基于Delta-Sigma调制(DSM)的高阶QAM传输系统。通过采用1-bit量化的DSM,成功将携带有高阶QAM的离散多音调制(DMT)信号量化编码为开关键控(OOK)信号,实现了高阶QAM信号在O波段强度调制/直接检测(IM/DD)系统中的传输。由于DSM拥有较高的量化信噪比,系统最高支持满足软判决2.4×10-2阈值的4096QAM信号的传输。特别地,通过采用预均衡技术,成功实现了50/100 Gbaud DSM信号分别在O波段的50/15 km的传输。实验演示了高速DSM信号在O波段的传输系统,为高阶QAM信号在IM/DD链路的传输提供了解决方案,同时也为未来基于DSM技术的高速移动前传方案设计提供了参考。

关键词：光通信 Delta-Sigma调制移动前传强度调制/直接检测

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连铸机开浇炉次与时间决策的多目标优化

计算机集成制造系统 2017年第2期23卷 261-272页

作者：龚永民郑忠龙建宇高小强重庆大学材料科学与工程学院重庆400045 攀枝花钢铁集团公司提钒炼钢厂四川攀枝花617000 重庆大学经济与工商管理学院重庆400044

针对连铸机开浇决策中的炉次选择、排序与开浇时间确定的多目标优化问题,以炼钢厂生产批量计划执行情况的总惩罚、生产线积压金属量、优质铁水非有效利用量最小为目标函数,构建了连铸机开浇炉次与时间决策的多目标优化模型。针对该模型... 详细信息

针对连铸机开浇决策中的炉次选择、排序与开浇时间确定的多目标优化问题,以炼钢厂生产批量计划执行情况的总惩罚、生产线积压金属量、优质铁水非有效利用量最小为目标函数,构建了连铸机开浇炉次与时间决策的多目标优化模型。针对该模型特点设计了改进的非支配排序遗传算法,以预选池内选择的炉次序号为基因的编码方式减小模型解的无效搜索空间,采取调整传统精英解集的计算顺序、限定计算拥挤距离个体数目的改进措施来减轻计算负荷,利用对Pareto解进行模糊选优的方法确定最终优化解。以某钢厂的生产实例数据测试表明,该模型有利于连铸生产炉次浇铸周期的稳定控制,算法效率优于传统的非支配排序遗传算法和强度Pareto进化算法。

关键词：连铸机生产调度开浇决策多目标优化改进的非支配排序遗传算法

中厚板考虑母板和板坯规格不确定性的下料问题建模及求解

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计算机集成制造系统 2017年第11期23卷 2508-2517页

作者：呼万哲郑忠龙建宇高小强重庆大学材料科学与工程学院重庆400045 重庆大学经济与工商管理学院重庆400044

针对中厚板面向订单的生产是先设计母板及板坯后实施的生产组织模式,研究综合考虑母板、板坯允许的多种断面与长度规格及其转换关系的母板板坯集成优化设计问题,将其归结为一种同时对母板、板坯断面及长度规格不确定性进行决策的下料问... 详细信息

针对中厚板面向订单的生产是先设计母板及板坯后实施的生产组织模式,研究综合考虑母板、板坯允许的多种断面与长度规格及其转换关系的母板板坯集成优化设计问题,将其归结为一种同时对母板、板坯断面及长度规格不确定性进行决策的下料问题。以最小化无订单余材和热轧切边等加工过程材料损失为目标,将板坯的断面与长度设计柔性转化为模型的约束条件,建立非线性混合整数规划模型;设计结合禁忌搜索与列生成技术的混合优化求解算法:禁忌搜索编码采用一对多的映射方式降低搜索空间维数,以进行板坯断面的优化选择;解码时对母板、板坯长度和下料方法进行设计,子问题为考虑长度柔性和材料加工损耗的母板设计问题,通过设计改进的列生成方法求解;针对问题特征设计了适用的邻域结构、禁忌对象等算法要素。基于某钢铁企业生产数据进行案例计算,结果表明了所提模型及求解方法的可行性和有效性。

关键词：下料问题母板设计板坯设计禁忌搜索列生成