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Compound solitons in fiber Bragg grating

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Science in China(Series F) 2008年第8期51卷 1177-1183页

作者： li XiaoLu JIANG yuesong School of Electronics and Information Engineering Beihang University Beijing 100083 China

Single soliton and compound solitons are described by coupled-mode equation. It is noted that three parameters, which are dimensionless group velocity, normalized frequency, and grating strength, influence formed solitons by emulation. The novel designs of parallel and serial multi-grating are advanced, and the compound solitons formed from parallel multi-grating are linear superposition; the compound solitons formed from serial multi-grating are nonlinear superposition, and finally two general formulae are obtained. Furthermore, it is theoretically shown that the compound grating solitons are prominent and flexible signals in optical communication.

关键词： fiber Bragg grating soliton coupled-mode equation dimensionless group velocity normalized frequency,grating strength

Effects of Climate Variability on Habitat Range and Distribution of Chub Mackerel in the East China Sea

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Journal of Ocean University of China 2021年第6期20卷 1483-1494页

作者： YU Wei WEN Jian CHEN Xinjun li Gang li yuesong ZHANG Zhong College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China Laboratory for Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China National Engineering Research Center for Oceanic Fisheries Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China Key Laboratory of Oceanic Fisheries Exploration Ministry of Agriculture and Rural AffairsShanghai 201306China Scientific Observing and Experimental Station of Oceanic Fishery Resources Ministry of Agriculture and Rural AffairsShanghai 201306China

Spatio-temporal distribution of chub mackerel Scomber japonicus is strongly susceptible to climate *** this study,a weighting-based habitat suitability index(HSI)model was established to assess the impacts of Pacific Decadal Oscillation(PDO)on habitat range and distribution of *** in the East China Sea(ECS)using vertical water temperature at depths of 2.5 m,25 m and 50 *** showed that the optimal HSI model selected from ten weighting scenarios can yield reliable *** analysis revealed a significant negative relationship between the PDO index and water temperature anomaly at different *** water temperatures at three different layers on the fishing ground of *** tended to be low in the warm PDO phase and high in the cold PDO phase,*** range of suitable habitats and its spatial distribution exhibited large differences between the warm and cold PDO *** a warm PDO phase,vertical water temperature became cool,and the monthly preferred water temperature at each depth for *** shifted ***,habitat quality dramatically decreased,and suitable habitat ranges also reduced and moved ***,in a cool PDO phase,with the warmer vertical water temperature and northwestward shift of the preferred water temperature,the suitable habitats enlarged and migrated in the same *** findings indicate that the PDO produced significant impacts on habitat range and distribution of *** in the East China Sea.

关键词： Scomber japonicus habitat pattern vertical water temperature Pacific Decadal Oscillation the East China Sea

Simulation Study on the Interannual Variation of the Transport and Distribution of Chub Mackerel (Scomber japonicus) Larvae and Juveniles Using Individual-Based Model

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Journal of Ocean University of China 2022年第5期21卷 1273-1282页

作者： YU Wei FENG Zhiping PAN lingzhi GUAN Wenjiang ZHANG Yu li yuesong College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China East China Sea Forecast Center State Oceanic AdministrationShanghai 200081China National Engineering Research Center for Oceanic Fisheries Shanghai Ocean UniversityShanghai 201306China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of EducationShanghai Ocean UniversityShanghai 201306China

An individual-based model of Scomber japonicus in the East China Sea(ECS)was developed to simulate the effects of physical environment on the transport and distribution of eggs,larvae and juveniles of *** from 1978 to *** results showed that there were interannual differences in the transport and distribution of eggs,larvae and juveniles of *** in the ECS due to different physical environments from 1978 to 2013,and this difference was extremely obvious in some specific *** current in the drift path of eggs and juveniles controlled and affected the transport process and distribution *** April,the distribution of eggs and larvae was mainly controlled by the Taiwan Warm Current(TWC).The number of eggs and larvae transported into the northeastern waters of the ECS was positively correlated with the intensity of *** May,it was mainly regu-lated by the TWC and the Tsushima Strait Warm Current(TSWC).In June,the number of larvae and juveniles entering the Tsushima Strait and the Pacific Ocean was determined by the *** general,in the years with high number of larvae and juveniles into the Tsushima Strait,the catch of 0-year-old *** was also *** addition,the number of larvae and juveniles entering the Tsushima Strait in El Niño years was less than that in La Niña *** July,the transport was mainly controlled by the Kuroshio Current(KC),and the eddy within the KC strongly affected its distribution.

关键词： individual-based model Scomber japonicus transport and distribution Taiwan Warm Current Tsushima Strait Warm Current Kuroshio Current

Objective evaluation of similarity scores derived by Evofinder^(®) system for marks on bullets fired from Chinese Norinco QSZ-92 pistols

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Forensic Sciences Research 2022年第1期7卷 40-46页

作者： Feng Dong Yabin Zhao Yaping Luo Weifang Zhang yuesong li School of Forensic Science People’s Public Security University of ChinaBeijingChina Shanghai Key Laboratory of Crime Scene Evidence Shanghai Research Institute of Criminal Science and TechnologyShanghaiChina Graduate School People’s Public Security University of ChinaBeijingChina

In recent years,many studies have been conducted in the field of firearm identification with the objective of providing an objective method of evaluating the comparison of cartridge ***,less attention has been paid to the objective evaluation of bullet *** this study,1000 registered Chinese Norinco QSZ-92 pistols were used,and a database of 2996 bullets was *** the receiver operating characteristic(ROC)curve and the score-based likelihood ratio method were used to objectively evaluate the similarity scores derived by the EvofinderVR *** results indicate that this system has excellent ability to discriminate between the selected *** paper proposes an objective evaluation method,which serves as a response to the ongoing debates regarding the foundation of the discipline.

关键词： Forensic sciences firearm identification EvofinderVR likelihood ratio automatic correlation

面向东海生态系统的OSMOSE-ECS模型构建与应用

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大连海洋大学学报 2022年第6期37卷 993-1003页

作者：黄猛李曰嵩上海海洋大学海洋科学学院上海201306 国家远洋渔业工程技术研究中心上海201306 大洋渔业资源可持续开发省部共建教育部重点实验室上海201306 远洋渔业协同创新中心上海201306

东海海域是中国重要的渔场,为了更有效地管理与保护东海渔业资源,基于东海生态系统建立了面向对象的海洋生态系统估计模型(object-oriented simulator of marine ecosystems exploitation, OSMOSE),并以鲐Scomber japonicus等19种东海... 详细信息

东海海域是中国重要的渔场,为了更有效地管理与保护东海渔业资源,基于东海生态系统建立了面向对象的海洋生态系统估计模型(object-oriented simulator of marine ecosystems exploitation, OSMOSE),并以鲐Scomber japonicus等19种东海海域常见的主要经济物种为对象,模拟了未对捕捞作业进行限制的条件下,各物种的平均营养级、生物量和平均体长等参数的变化趋势。结果表明:本研究中建立的面向东海的OSMOSE-ECS模型,在较缺乏实际输入数据的情况下,通过观测数据验证该模型能够合理模拟东海生态系统;在模拟的10年内东海生态系统种群结构发生了较大变化,总生物量平均水平比较平稳,但生物量平均营养级由3.53下降至3.16,高营养级个体比例降低;大部分经济鱼类的体长在波动中缓慢下降,整体体长结构偏小。研究表明,OSMOSE-ECS模型对东海渔业种群状态变化的模拟结果与实际情况吻合,若不采取有效的渔业管理措施,东海生态系统不可避免地会发生高营养级生物减少及物种个体趋于小型化、低龄化等衰退的现象,利用OSMOSE-ECS模型对东海海洋渔业资源管理和生态系统评估提供支持是可行的。

关键词：东海海洋生态系统估计模型(OSMOSE) 渔业管理营养级生物量

射流伺服阀用放大型超磁致伸缩执行器建模及分析

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航空学报 2014年第11期35卷 3156-3165页

作者：朱玉川李跃松南京航空航天大学机电学院江苏南京210016

为提高射流伺服阀的动态性能,设计了采用桥式微位移放大机构的射流伺服阀用放大型超磁致伸缩执行器(AGMA)。建立了计输入位移损失的放大机构模型以及非线性位移输出理论模型,并采用有限元法对所建放大机构模型进行了对比验证,结果表明:... 详细信息

为提高射流伺服阀的动态性能,设计了采用桥式微位移放大机构的射流伺服阀用放大型超磁致伸缩执行器(AGMA)。建立了计输入位移损失的放大机构模型以及非线性位移输出理论模型,并采用有限元法对所建放大机构模型进行了对比验证,结果表明:放大机构的输入刚度模型最大误差40Hz,谐振频率约为30Hz。

关键词：超磁致伸缩执行器射流伺服阀动态模型微位移放大刚度有限元法

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超磁致伸缩执行器驱动的新型射流伺服阀

压电与声光 2010年第4期32卷 574-577页

作者：朱玉川李跃松南京航空航天大学江苏省精密与微细制造技术重点实验室江苏南京210016

论述了超磁致伸缩材料在电液控制元件中的应用研究现状,基于超磁致伸缩材料的特点和未来航空航天领域对高频大流量伺服阀的迫切需求,提出了一种由超磁致伸缩执行器驱动的新型射流伺服阀的结构,分析了其工作原理与特点,同时对该新结构伺... 详细信息

论述了超磁致伸缩材料在电液控制元件中的应用研究现状,基于超磁致伸缩材料的特点和未来航空航天领域对高频大流量伺服阀的迫切需求,提出了一种由超磁致伸缩执行器驱动的新型射流伺服阀的结构,分析了其工作原理与特点,同时对该新结构伺服阀涉及的温度控制、热补偿、预压力施加与零位调节与驱动磁场均匀化等关键技术进行了详细分析并给出了具体实施方法。

关键词：超磁致伸缩执行器射流伺服阀热补偿预压力

2005—2016年中国东海鲐鱼渔场的时空分布及与海表面温度的关联

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上海海洋大学学报 2022年第3期31卷 710-720页

作者：李宜锴方星楠余为李曰嵩上海海洋大学海洋科学学院上海201306 国家远洋渔业工程技术研究中心上海201306 大洋渔业资源可持续开发教育部重点实验室上海201306 农业农村部大洋渔业开发重点实验室上海201306 农业农村部大洋渔业资源环境科学观测实验站上海201306

根据2005—2016年7—9月中国远洋渔业数据中心提供的我国东海鲐鱼捕捞数据,结合关键因子海表面温度(sea surface temperature, SST),计算各年鲐鱼渔场经纬度重心,量化鲐鱼渔场重心的时空变化。进一步分析捕捞努力量在经度、纬度以及SST... 详细信息

根据2005—2016年7—9月中国远洋渔业数据中心提供的我国东海鲐鱼捕捞数据,结合关键因子海表面温度(sea surface temperature, SST),计算各年鲐鱼渔场经纬度重心,量化鲐鱼渔场重心的时空变化。进一步分析捕捞努力量在经度、纬度以及SST上的分布规律,并基于聚类法筛选出代表年份,评估异常气候事件对鲐鱼渔场内SST及渔场重心时空分布的影响。研究结果显示,鲐鱼渔场重心具有明显的年际和月间变化,7—9月渔场逐渐向东北方向移动,且主要分布渔场SST为25~28℃。聚类分析将各月份渔场重心分为4类,其中2007和2015年渔场分布具有显著差异。此外,鲐鱼渔场内SST与尼诺指数具有显著的正相关关系,且代表年份2007和2015年分别对应拉尼娜事件和厄尔尼诺事件,当拉尼娜事件发生时,渔场内SST上升,渔场重心逐渐北移;而厄尔尼诺事件发生时,渔场内SST下降,渔场重心主要分布在南部海域。研究表明,中国东海鲐鱼渔场时空分布受到厄尔尼诺和拉尼娜调控的海表面温度变化的显著影响。

关键词：鲐鱼时空分布聚类分析拉尼娜厄尔尼诺海表面温度

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基于机器视觉的煤炭排矸系统设计

煤炭技术 2023年第9期42卷 273-275页

作者：李鑫李跃松鹤壁职业技术学院机电工程学院河南鹤壁458030 河南科技大学机电工程学院河南洛阳471003

针对传统煤矸石分拣采用人工方式,错选率高、效率低等问题,设计了基于机器视觉的煤炭排矸系统。利用YOLOv3+VGG16卷积神经网络对煤矸石进行两级目标检测,采用三维执行机构实现煤矸石自动抓取,设计控制方法协调系统各模块工作。装置加装... 详细信息

针对传统煤矸石分拣采用人工方式,错选率高、效率低等问题,设计了基于机器视觉的煤炭排矸系统。利用YOLOv3+VGG16卷积神经网络对煤矸石进行两级目标检测,采用三维执行机构实现煤矸石自动抓取,设计控制方法协调系统各模块工作。装置加装在带式输机上进行试验,煤矸石分选的正确率达到96%以上,对比人工方式效率有明显的提升,证明系统具有较强的应用潜力。

关键词：机器视觉煤矸石分拣 YOLOv3 VGG16 三维执行机构