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一类工作点可变线性系统的镇定控制器设计

上海交通大学学报 2000年第5期34卷 657-660页

作者：袁向阳施颂椒 masao ikeda 上海交通大学自动化系上海200030 日本大阪大学工学部

对于一类工作点可变的线性系统 ,即被控系统表达为两个典型工作点上的传递函数矩阵的正则稳定的既约分解的线性内插 ,考虑其镇定控制器设计问题 .假设被控对象在典型工作点上的传递函数矩阵的既约分解组成一个集合 ,提出了镇定该集合的... 详细信息

对于一类工作点可变的线性系统 ,即被控系统表达为两个典型工作点上的传递函数矩阵的正则稳定的既约分解的线性内插 ,考虑其镇定控制器设计问题 .假设被控对象在典型工作点上的传递函数矩阵的既约分解组成一个集合 ,提出了镇定该集合的控制器的设计方法 .对于线性内插系数不可知的情形 ,提出了两种固定型镇定控制器的设计方法 ;对于线性内插系数可知的情形 ,提出了一种内插型镇定控制器设计方法 .文中将控制器的设计问题转化为 H∞ 控制问题 ,再转化为状态空间下的基于线性矩阵不等式 ( LMI)

关键词：线性系统工作点可变镇定控制器 LMI H∞控制

Room-temperature continuous-wave electrically pumped InGaN/GaN quantum well blue laser diode directly grown on Si

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Light(Science & Applications) 2018年第1期7卷 904-910页

作者： Yi Sun Kun Zhou Meixin Feng Zengcheng Li Yu Zhou Qian Sun Jianping Liu Liqun Zhang Deyao Li Xiaojuan Sun Dabing Li Shuming Zhang masao ikeda Hui Yang Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)Suzhou 215123China School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026China Accelink Technologies Co. LtdWuhan 430205China State Key Laboratory of Luminescence and Applications Changchun Institute of Optics Fine Mechanics and Physics(CIOMP)CASChangchun 130033China

Current laser-based display and lighting applications are invariably using blue laser diodes(LDs)grown on freestanding GaN substrates,which are costly and smaller in size compared with other substrate materials.1–3 Utilizing less expensive and large-diameter Si substrates for hetero-epitaxial growth of indium gallium nitride/gallium nitride(InGaN/GaN)multiple quantum well(MQW)structure can substantially reduce the cost of blue LDs and boost their *** obtain a high crystalline quality crack-free GaN thin film on Si for the subsequent growth of a blue laser structure,a hand-shaking structure was formed by inserting Al-composition step down-graded AlN/AlxGa1−xN buffer layers between GaN and Si *** degradation in InGaN/GaN blue MQWs was successfully suppressed with indium-rich clusters eliminated by introducing hydrogen during the growth of GaN quantum barriers(QBs)and lowering the growth temperature for the p-type AlGaN/GaN superlattice optical cladding layer.A continuous-wave(CW)electrically pumped InGaN/GaN quantum well(QW)blue(450 nm)LD grown on Si was successfully demonstrated at room temperature(RT)with a threshold current density of 7.8 kA/cm^(2).

关键词： pumped quantum wave

GaN-based ultraviolet microdisk laser diode grown on Si

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Photonics Research 2019年第6期7卷 I0034-I0037页

作者： JIN WANG MEIXIN FENG RUI ZHOU QIAN SUN JIANXUN LIU YINGNAN HUANG YU ZHOU HONGWEI GAO XINHE ZHENG masao ikeda HUI YANG Key Laboratory of Nano-Devices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 China University of Science and Technology Beijing Beijing 100083 China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesNanchang 330200 China School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026 China

This work reports a demonstration of electrically injected GaN-based near-ultraviolet microdisk laser diodes with a lasing wavelength of 386.3 nm at room temperature. The crack-free laser structure was epitaxially grown on Si substrates using an Al-composed down-graded Al N/AlGaN multilayer buffer to mitigate the mismatches in the lattice constant and coefficient of thermal expansion, and processed into “sandwich-like” microdisk structures with a radius of 12 μm. Air-bridge electrodes were successfully fabricated to enable the device electrical characterization. The electrically pumped lasing of the as-fabricated microdisk laser diodes was evidenced by the rapid narrowing down of electroluminescence spectra and dramatic increase in the light output power, as the current exceeded the threshold of 248 mA.

关键词： laser diode ultraviolet

No-touch isolation technique in emergency pancreaticoduodenectomy for neoplastic hemorrhage: Two case reports and review of literature

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1910-1917页

作者： Akihiro Cho Satoshi Katagiri masao Ota Shunsuke Onizawa Ryota Higuchi Toshiya Sugishita Yukiko Niwa Takeshi Ishita Toshihiko Mouri Akita Kato Moe Iwata Division of Gastroenterological Surgery Tokyo Women’s Medical UniversityYachiyo Medical CenterChiba 276-8524Japan

BACKGROUND Emergency pancreaticoduodenectomy(EPD)is a rare event for complex periam-pullary *** intraoperative blood loss is correlated with poor post-operative *** SUMMARY Two patients underwent EPD using a no-touch isolation technique,in which all arteries supplying the pancreatic head region were ligated and divided before manipulation of the pancreatic head and *** operative times were 220 and 239 min,and the blood loss was 70 and 270 g,*** patients were discharged on the 14^(th) and 10^(th) postoperative day,***-two patients underwent EPD for the treatment of neoplastic *** mean operative time was 361.6 min,and the mean blood loss was 747.3 *** comp-lication rate was 37.5%.The in-hospital mortality rate was 9.38%.CONCLUSION The no-touch isolation technique is feasible,safe,and effective for reducing intraoperative blood loss in EPD.

关键词： No-touch isolation technique Pancreaticoduodenectomy Emergency pancre-aticoduodenectomy Neoplastic bleeding Superior mesenteric artery first approach Case report

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基于学习的自校正控制算法

上海交通大学学报 2000年第4期 516-516页

作者：袁向阳,施颂椒,masao ikeda 上海交通大学自动化系!上海200030 上海交通大学自动化系!上海200030 日本大阪大学工学部!大阪565-0834

提出了一种基于学习的自校正控制算法 ,算法中包含一个自适应模型和多个固定模型 ,每一个模型都有一个相对应的控制器 .在每一采样时刻 ,将当前时段内具有最小预测误差的模型对应的控制器的输出作为控制输入 .在该算法中 ,自适应模型和自适应控制器的作用是确保闭环系统的稳定性和输出跟踪误差的渐近收敛性 ,而固定模型和固定控制器的作用是当被控对象的参数发生变化时 ,在自适应模型的参数估计收敛之前 ,暂时担当控制器的角色 ,以改善闭环系统的暂态响应 .证明了闭环系统的稳定性和输出跟踪误差的渐近收敛性 .仿真结果表明算法的有效性

关键词：自校正控制随机自适应控制算法控制器调节器闭环系统反馈调节系统控制系统基于学习

Effect of inhomogeneous broadening on threshold current of GaN-based green laser diodes

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Journal of Semiconductors 2019年第5期40卷 67-70页

作者： Yipeng Liang Jianping Liu masao ikeda Aiqin Tian Renlin Zhou Shuming Zhang Tong Liu Deyao Li Liqun Zhang Hui Yang School of Nano Technology and Nano Bionics University of Science and Technology of China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Science Key Laboratory of Nanodevices and Applications Chinese of Academy of Science Vacuum Interconnected Nanotech Workstation NANO-X Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences

The inhomogeneous broadening parameter and the internal loss of green LDs are determined by experiments and theoretical fitting. It is found that the inhomogeneous broadening plays an important role on the threshold current density of green LDs. The green LD with large inhomogeneous broadening even cannot lase. Therefore, reducing inhomogeneous broadening is a key issue to improve the performance of green LDs.

关键词： GaN green laser diode inhomogeneous broadening threshold current density

Reduced threshold current density of GaN-based green laser diode by applying polarization doping p-cladding layer

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Chinese Optics Letters 2021年第12期19卷 45-50页

作者：江灵荣刘建平胡磊张立群田爱琴熊巍任霄钰黄思溢周伟池田昌夫杨辉 Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of SciencesSuzhou 215123China School of Nano-tech and Nano-bionics University of Science and Technology of ChinaHefei 230026China Key Laboratory of Nanodevices and Applications Chinese Academy of SciencesSuzhou 215123China Nano Science and Technology Institute University of Science and Technology of ChinaHefei 230026China

Absorption induced by activated magnesium(Mg)in a p-type layer contributes considerable optical internal loss in Ga Nbased laser diodes(LDs).An LD structure with a distributed polarization doping(DPD)p-cladding layer(CL)without intentional Mg doping was designed and *** influence of the anti-waveguide structure on optical confinement was studied by optical *** threshold current density,slope efficiency of LDs with DPD p-CL,and Mg-doped CL,respectively,were *** was found that LDs with DPD p-CL showed lower threshold current density but reduced slope efficiency,which were caused by decreasing internal loss and hole injection,respectively.

关键词： polarization doping internal loss GaN laser diode

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两种镇定控制器镇定范围的分析

应用科学学报 2001年第1期19卷 89-91页

作者：袁向阳施颂椒 ikeda masao 上海交通大学自动化系上海200030 大阪大学日本大阪5650871

对于一类工作点可变的单输入输出线性系统 ,被控系统表达为两个典型工作点上传递函数即正则稳定又既约分解的线性内插 .文献 [1,2 ]提出了一种固定型镇定控制器设计方法 ,文献 [3]则提出了一种内插型镇定控制器设计方法 ,文中从理论上... 详细信息

对于一类工作点可变的单输入输出线性系统 ,被控系统表达为两个典型工作点上传递函数即正则稳定又既约分解的线性内插 .文献 [1,2 ]提出了一种固定型镇定控制器设计方法 ,文献 [3]则提出了一种内插型镇定控制器设计方法 ,文中从理论上证明了文献

关键词：工作点可变系统固定型镇定控制器内插型镇定控制器镇定范围线性内插系数被控对象

改善势能均匀性提升c面InGaN绿光激光器性能

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Science China Materials 2022年第2期65卷 543-546页

作者：田爱琴胡磊李暄吴思徐鹏王旦周韧林郭炳磊李方直周伟李德尧池田昌夫杨辉刘建平 Suzhou Institute of Nano-tech and Nano-bionics Chinese Academy of SciencesSuzhou 215123China Key Laboratory of Nanodevices and Applications Chinese Academy of SciencesSuzhou 215123China School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026China Guangdong(Foshan)Branch Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesFoshan 528000China

激光显示、医疗设备及量子通信迫切需求高性能GaN基绿光激光二极管(LD).研制绿光LD最大的挑战是生长高势能均匀性的InGaN/GaN多量子阱.我们采用各种光学测量手段对绿光LD结构和芯片进行了表征.在激发功率密度为7 W cm^(-2)时,300 K下光... 详细信息

激光显示、医疗设备及量子通信迫切需求高性能GaN基绿光激光二极管(LD).研制绿光LD最大的挑战是生长高势能均匀性的InGaN/GaN多量子阱.我们采用各种光学测量手段对绿光LD结构和芯片进行了表征.在激发功率密度为7 W cm^(-2)时,300 K下光致发光半高宽为108 meV,电流密度为20 A cm^(-2)时,电致发光半高宽为114 meV,这些研究结果表明势能均匀性得到了显著改善.同时,由变温光致发光测试得到的表征局域态分布宽度的σ值和由时间分辨光致发光测试得到的表征激子局域带尾态的E0值都很小,进一步表明势能均匀性很好.由于势能均匀性的极大改善,实现了斜率效率0.8 W A^(-1),输出光功率可以达到1.7 W的绿光LD芯片.

关键词：光致发光输出光功率绿光激光器激光显示量子通信电致发光斜率效率光学测量