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单片集成25 Gb/s电吸收调制器的O波段可调谐V型腔激光器

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光学学报 2024年第11期44卷 144-149页

作者：夏诒民孟剑俊李乔力何建军浙江大学光电科学与工程学院现代光学仪器国家重点实验室浙江杭州310012 杭州兰特普光电子技术有限公司浙江杭州310058

本文实现了O波段可调谐的25 Gb/s电吸收调制激光器(EML)光发射器芯片和封装器件,该EML芯片单片集成了大范围可调谐V型腔激光器和电吸收调制器,并采用了相同的外延层方案。在O波段,该器件实现了20个信道、100 GHz间隔的波长调谐,边模抑... 详细信息

本文实现了O波段可调谐的25 Gb/s电吸收调制激光器(EML)光发射器芯片和封装器件,该EML芯片单片集成了大范围可调谐V型腔激光器和电吸收调制器,并采用了相同的外延层方案。在O波段,该器件实现了20个信道、100 GHz间隔的波长调谐,边模抑制比超过37 dB。当驱动电压峰峰值固定为2 V时,所有信道在25 Gb/s的速率下显示出清晰的眼图,动态消光比均超过5 dB。误码率测量表明,当通过25 km的标准单模光纤传输后,器件的所有信道都没有色散代价。

关键词：激光器电吸收调制器可调谐激光器单片集成

水射流构造自由面下滚刀线性切割破岩特性研究

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哈尔滨工程大学学报 2024年第2期45卷 367-374页

作者：张旭辉谭涛钟科龙金京夏毅敏湖南师范大学工程与设计学院湖南长沙410081 中南大学机电工程学院湖南长沙410083

为了分析水射流构造自由面情况下的滚刀切割破岩特性,本文采用有限元模拟分析方法,建立自由面工况下滚刀破岩模型,模拟不同切宽下滚刀切割岩石动态过程,得到水射流构造自由面工况下滚刀破岩载荷、破岩状态等变化规律,并利用线性切割实... 详细信息

为了分析水射流构造自由面情况下的滚刀切割破岩特性,本文采用有限元模拟分析方法,建立自由面工况下滚刀破岩模型,模拟不同切宽下滚刀切割岩石动态过程,得到水射流构造自由面工况下滚刀破岩载荷、破岩状态等变化规律,并利用线性切割实验进行验证。研究结果表明:水射流构造自由面后滚刀切割过程中,岩石会产生表面和内部拉伸裂纹,且当切宽小于临界值50 mm时,滚刀临近自由面侧的拉伸裂纹可以延伸到自由面,促进岩石破碎;水射流构造自由面情况下的滚刀破岩垂直载荷最大,侧向载荷最小,且合适的切宽可以显著改善滚刀受载;当滚刀能有效利用水射流构造的自由面破岩时,其破岩比能耗远低于无自由面效应下的滚刀破岩比能耗,前者仅约为后者的30%,破岩效率得到显著提高。研究结果可为水射流辅助滚刀破岩参数设计提供依据。

关键词：水射流自由面有限元模拟滚刀切割切宽破岩载荷破岩效率

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大直径盾构隧道成型质量巡检方法研究

工程科学学报 2024年第2期46卷 365-375页

作者：赵先琼邓凯张亚洲马英博夏毅敏中南大学机电工程学院长沙410083 中铁十四局集团大盾构工程有限公司南京211899

针对因工业应用成本限制,中、小盾构隧道成型质量无损检测技术迁移至大直径盾构隧道时精度、速度折损严重的问题,以巡检车为载体,集成二维激光扫描仪、编码器和计算机等设备,研制了大盾构隧道成型质量巡检车,并提出一种基于数字图像的... 详细信息

针对因工业应用成本限制,中、小盾构隧道成型质量无损检测技术迁移至大直径盾构隧道时精度、速度折损严重的问题,以巡检车为载体,集成二维激光扫描仪、编码器和计算机等设备,研制了大盾构隧道成型质量巡检车,并提出一种基于数字图像的盾构质量非对称巡检方法.分析大直径盾构的施工环境,滤除地面、车体点云,并采用邻域向量法提取中轴线,建立隧道中心坐标系.偏心布置巡检路线,按照点云密度将采样点云分为稠密侧和稀疏侧点云,通过不同方法实现对管片接缝特征的拾取:将稠密侧点云绕中轴线展开为二维灰度图像,并通过缩放、归一化、梯度阈值分割等方法实现接缝图像分割;基于直线方程对接缝进行分类,结合管片结构、布置点位,推导出稀疏侧接缝与稠密侧接缝的线性分布公式,间接拾取稀疏侧接缝.根据接缝特征点计算两侧管片边缘点云簇,计算管片错台量;剔除接缝点云簇,使用最小二乘法拟合隧道点云,计算隧道椭圆度.最后在某大直径盾构隧道进行巡检试验,试验结果表明:成型质量巡检车在十四米盾构隧道中巡检速度为3 km·h-1,与传统方法的错台量检测偏差小于2 mm,椭圆度检测偏差小于0.1%,可以满足大直径盾构隧道成型质量巡检的高速度、高精度、低成本需求.

关键词：大直径盾构隧道激光扫描阈值分割错台检测变形检测

Field and laboratory experimental studies on hard-rock tunnel excavation based on disc cutter coupled with high-pressure waterjet

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Frontiers of Structural and Civil Engineering 2023年第9期17卷 1370-1386页

作者： He FEI Yiqiang LU Jinliang ZHANG Xingchen LUO yimin xia College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China China Railway Engineering Equipment Group Co. Ltd.Zhengzhou 450016China College of Civil Engineering Tongji UniversityShanghai 200092China Yellow River Engineering Consulting Co. Ltd.Zhengzhou 450003China

The tunnel boring machine(TBM)is typically used in hard-rock tunnel *** to the unsatisfactory adaptability of TBM to the surrounding rock,when crossing high-strength and high-wear strata,the TBM can easily cause defects,such as abnormal wear on cutters and overload damage to bearings,thus affecting the construction efficiency and ***,high-pressure waterjet technology should be applied to assist in rock breaking for efficient TBM *** this study,the effects of water pressure,nozzle diameter,and nozzle speed on cutting are investigated via laboratory experiments of cutting hard rock using high-pressure *** penetration performance of the TBM under different water pressures is investigated via a field industrial penetration *** results show that high-pressure waterjets are highly efficient for rock breaking and are suitable for industrial applications,as they can accommodate the advancing speed of the TBM and achieve high-efficiency rock ***,during the operation of high-pressure waterjets,the ambient temperature and waterjet temperature in the tunnel increase significantly,which weakens the cooling effect of the cutterhead and decreases the construction efficiency of the ***,temperature control and cooling measures for high-pressure waterjets during their long-term operation must be *** study provides a useful reference for the design and construction of high-pressure water-jet-assisted cutterheads for breaking road headers.

关键词： tunnel boring machine hard-rock cutting free face disc cutter rock-cutting efficiency

Aφ6-m Tunnel Boring Machine Steel Arch Splicing Manipulator

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 121-134页

作者： Yuanfu He yimin xia Zhen Xu Jie Yao Bo Ning Xuemeng xiao College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China China Railway Construction Heavy Industry Co.Ltd. Changsha 410100China China Railway Siyuan Survey and Design Group Co.Ltd. Wuhan 430063China National-Local Joint Engineering Research Center of Underwater Tunnelling Technology Wuhan 430063China

Robotic splicing of steel arches is a challenging task that is necessary to realize the grasping and docking of steel arches in a limited *** arches often have a mass of more than 200 kg and length of more than 4 *** to the large volume and mass of steel arches and the high requirements for accurately positioning the splicing,it is difficult for a general manipulator to meet the stiffness *** enhance the structural stiffness of the steel arch splicing manipulator,a single-degree-of-freedom(DOF)closed-loop mechanism was added to the grasping structure of the *** on the basic principle of structural synthesis,a solution model of the single-DOF closed-loop mechanism was developed,and alternative kinematic pairs of the mechanism with different input constraints and output requirements were *** on this model,a design method for a single-DOF closed-loop grasping mechanism and a posture adjustment mechanism for a steel arch was *** with the same dimensional subspace equivalence principle of the graphical-type synthesis method,12 types of steel arch splicing manipulator were *** analyzing the motion/force transmission and structural complexity of the steel arch splicing manipulators,the best scheme was selected.A prototype of the steel arch splicing manipulator was *** software was used to obtain clearly the output trajectory of the end of the *** relative spatial positions of the upper and lower jaws under different working stages were analyzed,demonstrating that the manipulator satisfied the grasping *** a steel arch splicing experiment,the grasping effect,docking accuracy,and splicing efficiency of the manipulator met the design *** steel arch splicing manipulator can replace the manual completion of the steel arch splicing operation,significantly improving the operation efficiency.

关键词： Steel arch splicing manipulator Single-DOF closed-loop mechanism Screw theory Graphical-type synthesis method Mechanism design

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“五位一体、三升一融”教学模式研究

电气电子教学学报 2024年第2期46卷 28-30页

作者：杨健夏益民陈思哲陈平广东工业大学自动化学院广州510006 广东工业大学集成电路学院广州510006

针对传统课堂存在的问题,确立以学生为中心的教育理念。构建“多维化互动、泛在化感知、精准化评价、数据化决策、个性化引导”的“五位一体”的智慧教学感知评价体系,和“三步一综合”案例实验教学模式,实现学习获得感、自主学习热情... 详细信息

针对传统课堂存在的问题,确立以学生为中心的教育理念。构建“多维化互动、泛在化感知、精准化评价、数据化决策、个性化引导”的“五位一体”的智慧教学感知评价体系,和“三步一综合”案例实验教学模式,实现学习获得感、自主学习热情和创新实践能力的三轮提升。学生在课程成绩、学科竞赛、创新创业等方面有显著提升,课程获评国家级线上线下混合式一流课程、省级课程思政建设示范课程等。

关键词：混合式教学认知迭代案例融合

Dynamic Characteristics Analysis with Multi-Directional Coupling in a TBM Mainframe

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Chinese Journal of Mechanical Engineering 2019年第6期32卷 48-59页

作者： Laikuang Lin yimin xia Zhengguang Li Caizhang Wu Yongliang Cheng Qing Tan College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China China Railway Construction Heavy Industry Co. Ltd.Changsha 410100China

The cutterhead of a full-face rock tunnel boring machine(TBM)is constantly subjected to varying impact and dynamic loads during tunneling processes,resulting in relatively large vibrations that could easily lead to fatigue cracking of the entire machine and a ect the tunneling performance and *** explore the dynamic characteristics of the TBM mainframe,a TBM from a water-diversion project is investigated in this *** to the TBM vibration transmission route,an equivalent dynamic model of the TBM mainframe is established using the lumped-mass method in which the relevant dynamic parameters are ***,the dynamic response characteristics of the TBM mainframe are *** results indicate that the vibration levels in three directions are approximately the same,the multi-directional vibration of the cutterhead is more intense than that of other components,and the vibration and external excitation exhibit identical change trends.A set of vibration field tests is performed to analyze the in situ dynamic responses of the mainframe and verify the correctness of the dynamic *** theoretical and measured acceleration values of the TBM mainframe have the same magnitude,which proves the validity of the dynamic model and its *** aforementioned results provide an important theoretical value and practical significance for the design and assessment of the TBM mainframe.

关键词： Tunnel boring machine Time-varying excitation Dynamic model Load transfer Dynamic response

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类似卵巢性索肿瘤的子宫肿瘤1例并文献复习

临床医学研究与实践 2024年第7期9卷 41-44,97页

作者：牛蔓王亚楼王卉芳夏益敏李元鹏任雨洁钱薇陈若兰西安市人民医院/西安市第四医院病理科陕西西安710004 西安市人民医院/西安市第四医院妇产科陕西西安710004

目的探讨类似卵巢性索肿瘤的子宫肿瘤(UTROSCT)的临床及组织病理学特征、诊断与鉴别诊断。方法分析1例UTROSCT的临床资料,行组织形态学、免疫组化检查并复习相关文献。结果UTROSCT细胞排列呈小梁状、巢状,浸润周围平滑肌组织,部分瘤细... 详细信息

目的探讨类似卵巢性索肿瘤的子宫肿瘤(UTROSCT)的临床及组织病理学特征、诊断与鉴别诊断。方法分析1例UTROSCT的临床资料,行组织形态学、免疫组化检查并复习相关文献。结果UTROSCT细胞排列呈小梁状、巢状,浸润周围平滑肌组织,部分瘤细胞呈上皮样,胞浆嗜酸,部分瘤细胞胞浆透亮或泡沫状,核圆形、卵圆形及短梭形,染色质细腻,可见核沟,部分核仁显著,未见核分裂象、脉管内瘤栓及坏死。免疫组化显示细胞角蛋白(CK)、钙结合蛋白(CR)、CD99、inhibin-A、类固醇生成因子-1(SF-1)、肾母细胞瘤基因-1(WT-1)、雌激素受体(ER)、孕激素受体(PR)阳性;T细胞1识别黑色素瘤抗原(Melan-A)、S100、结蛋白灶状阳性;癌胚抗原(CEA)、上皮膜抗原(EMA)、多肿瘤抑制因子1(MTS/P16)、黑色素瘤相关抗原(HMB45)、平滑肌肌动蛋白(SMA)、CD10、CD34阴性;Ki67增殖指数约1%阳性。结论UTROSCT是一类罕见的具有卵巢性索间质肿瘤特征的子宫肿瘤,临床症状及影像学检查缺乏特异性,依赖术后病理组织形态学及免疫组化确诊,其生物学行为具有低度恶性潜能,大多数呈良性过程,需要长期随访。

关键词：类似卵巢性索肿瘤的子宫肿瘤临床病理特征免疫组化

Scavenging Effects of Kaolin on Fine Ash Formation during Zhundong Coal Combustion

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Energy Engineering 2021年第3期118卷 459-471页

作者： Fangqi Liu xianpeng Zeng yimin xia Zihao Wang Dunxi Yu State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074China WISDRI Engineering&Research Incorporation Limited Wuhan430223China

The previous work found that the additive kaolin could scavenge not only sodium(Na)but also calcium(Ca)and magnesium(Mg),which is the important ash fluxing agents in low rank coal *** scavenging effects of kaolin on fine ash formation were studied in the present work.A typical Zhundong coal and its blends with kaolin at dosages of 1,2 and 4 wt%were combusted in an electrically heated drop tube furnace(DTF)at 1300℃.The fine ashes generated were collected and size segregated by a low pressure impactor(LPI).The morphology and chemical composition of fine ash were analyzed by scanning electron microscopy equipped with an energydispersive spectrometer(SEM-EDS).In addition,char/ash particles were sampled at various positions of DTF to elucidate how kaolin additive affected the fine ash formation *** results further showed that apart from the scavenging of volatile Na,kaolin additive could also strongly scavenge the refractory Ca,Mg and Fe in the fine ash during Zhundong coal combustion,which transformed the sintered particles with irregular shape into melted spherical particles,and finally resulted in the considerable decrease of these elements in both PM_(0.4)and PM_(0.4-10)by melting and *** close contacts between kaolin particles and coal resulted from physically mixing were a key factor responsible for the reaction of kaolin with the refractory Ca,Mg and Fe.

关键词： Zhundong coal kaolin fine ash basic elements sodium ash deposition