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基于卡箍优化布局的飞机液压管路减振分析 被引量:47
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作者 李鑫 王少萍 《振动与冲击》 EI CSCD 北大核心 2013年第1期14-20,共7页
飞机液压管路振动过大是一个亟待解决的问题,考虑了主动消振方式较为复杂,难以在飞机液压系统实现,提出了基于系统特征阻抗,通过优化卡箍布局的被动消振方式。首先建立系统管道及各元件数学模型,利用传递矩阵法(Transfer Matrix Method,... 飞机液压管路振动过大是一个亟待解决的问题,考虑了主动消振方式较为复杂,难以在飞机液压系统实现,提出了基于系统特征阻抗,通过优化卡箍布局的被动消振方式。首先建立系统管道及各元件数学模型,利用传递矩阵法(Transfer Matrix Method,TMM)得到其频域特征阻抗变化规律。以激振源固有频率点的特征阻抗加权和为目标函数,利用粒子群优化算法(Particle Swarm Optimization,PSO)在一定范围内调整卡箍位置,使在激振源频率点的特征阻抗加权和降到最低。通过优化卡箍位置,系统特征阻抗加权和较优化前衰减28.13%,验证了其有效性,为飞机液压管路的优化布局提供了一定的理论依据。 展开更多
关键词 管路振动 传递矩阵法 特征阻抗 粒子群算法 卡箍 优化布局
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用传输矩阵法(TMM)研究二维光子晶体传输特性 被引量:21
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作者 梅洛勤 叶卫民 +4 位作者 曾淳 袁晓东 朱志宏 张晚云 王华 《量子光学学报》 CSCD 2003年第2期88-92,共5页
将传输矩阵法 (TMM )用于光子晶体传输特性的理论研究 ,采用Mur近似吸收边界和周期边界来截断计算区域 ,研究了以TM模正入射时 ,二维方格子光子晶体在完整周期结构下和有缺陷结构下的透过率谱 ;在微波波段制作了光子晶体模型 ,并设计了... 将传输矩阵法 (TMM )用于光子晶体传输特性的理论研究 ,采用Mur近似吸收边界和周期边界来截断计算区域 ,研究了以TM模正入射时 ,二维方格子光子晶体在完整周期结构下和有缺陷结构下的透过率谱 ;在微波波段制作了光子晶体模型 ,并设计了实验装置 ;实验与数值模拟计算取得了基本一致的结果。 展开更多
关键词 传输矩阵法 tmm 二维光子晶体 传输特性 光子禁带 吸收边界 透射谱 数值模拟
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TMM在软件质量保证中的作用 被引量:7
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作者 郭小群 侯红 鱼滨 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第1期19-22,共4页
目的 介绍软件质量保证(SQA)和TMM(测试成熟度模型),并介绍在一个组织中如何实施TMM。方法 对TMM和SQA从概念上及具体实施过程进行比较。结果 TMM是对SQA的一个补充,并在保证软件质量方面起着重要作用。结论 SQA从过程和产品两方面... 目的 介绍软件质量保证(SQA)和TMM(测试成熟度模型),并介绍在一个组织中如何实施TMM。方法 对TMM和SQA从概念上及具体实施过程进行比较。结果 TMM是对SQA的一个补充,并在保证软件质量方面起着重要作用。结论 SQA从过程和产品两方面来保证软件的质量,而测试成熟度模型仅关注过程的质量。为了提高软件的质量,企业必须改进测试过程。 展开更多
关键词 软件质量保证 测试 测试成熟度模型
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铁路隧道整体道床横断面的受力分析 被引量:7
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作者 刘庆潭 单立平 《铁道学报》 EI CAS CSCD 北大核心 2002年第5期93-97,共5页
采用传递矩阵法(TMM)对隧道整体道床典型横断面作了力学分析,所得的分析成果可为整体道床的设计和维护提供一些合理的科学参数。
关键词 铁路隧道 整体道床 横断面 受力分析 裂纹 传递矩阵法 tmm
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Fracture healing with osteopathy in traditional Mongolian medicine 被引量:9
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作者 Namula Zhao Mei Wang Xueen Li 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第1期130-133,共4页
OBJECTIVE: To explore the concept and norm of fracture healing with osteopathy in traditional Mongolian medicine (TMM). METHODS: Based on the correspondence between man and the universe (including psychosomatic integr... OBJECTIVE: To explore the concept and norm of fracture healing with osteopathy in traditional Mongolian medicine (TMM). METHODS: Based on the correspondence between man and the universe (including psychosomatic integration) in fracture healing with osteopathy in TMM, we used modern physio-psychological and biomechanical principles and methods to probe the integrated, dynamic and functional characteristics of fracture healing. RESULTS: Based on the integration of limbs and the body, unification of the body and function and harmony of man and nature (including psychoso-matic integration), fracture healing with osteopathy in TMM comprises the concept of natural functional healing of fractures, and follows the norm of considering physiological healing and psychological function as well as limb healing and motor function. CONCLUSION: Fracture healing with osteopathy in TMM is characterized by a lack of trauma without future complications. This therapy makes the concept of fracture healing develop in the direction of humanity, behaviorism and integration. 展开更多
关键词 Osteopathic medicine Fracture healing Recovery of function Mental healing
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真丝绸的免烫整理 被引量:5
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作者 张丽芝 张庆 《丝绸》 CAS 北大核心 1999年第3期28-29,共2页
介绍了用TMM和BTCA作整理剂的真丝绸免烫整理技术,比较了两者整理效果。认为BTCA是一种较理想的无甲醛真丝绸免烫整理剂。
关键词 真丝绸 免烫整理 tmm BTCA 整理剂
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Improve the Efficiency of Scintillation Detectors Using Reflectors Based on Photonic Crystals Arrays 被引量:4
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作者 M. F. Eissa Arafa H. Aly 《Journal of Electromagnetic Analysis and Applications》 2014年第2期25-29,共5页
In the present work, we designed the new type of photonic crystals (PCs) as reflectors. Reflections from single layer of Al2O3/MgO PC help us in recapturing the light that does escape from the scintillation surface. P... In the present work, we designed the new type of photonic crystals (PCs) as reflectors. Reflections from single layer of Al2O3/MgO PC help us in recapturing the light that does escape from the scintillation surface. Photonic crystals in one dimension array of Al2O3 and MgO with silver at periodicities N = 1, 2 and 3 were used as a reflector around the surface of the scintillation volume. Scintillation detectors are widely used in nuclear medicine. The efficiency is an important parameter for characterizing the capability of the detectors. The counting efficiency of the detectors depends on the light emission induced by radiation. The light then was converted by the photomultiplier tube into electrical pulses. The efficiency may increase by an amount of 1.64% if MgO-Ag photonic crystals are used at periodicity N = 1 as a reflector. 展开更多
关键词 tmm PHOTONIC CRYSTALS Scintillation Detectors Radiation PHOTONIC BAND Gap
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结构和缺陷对二维光子晶体传输性质的影响 被引量:3
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作者 周梅 陈效双 +2 位作者 季亚林 王少伟 陆卫 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2003年第3期229-233,共5页
用转移矩阵方法计算了二维光子晶体的传输性质 ,讨论了不同极化光的透射行为 ,比较了正方点阵、有心正方点阵、含缺陷有心正方点阵光子能带对透射特性的影响 ,获得了第一禁带特性与光子晶体结构的一些基本关系 .
关键词 二维光子晶体 光子禁带 转移矩阵法 透射系数 晶体结构 晶体缺陷
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基于VP的三种思想下实现红外坦克目标的仿真对比研究 被引量:3
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作者 孙嗣良 陈韧 +1 位作者 孙力 闫杰 《系统仿真学报》 CAS CSCD 北大核心 2011年第5期1032-1038,共7页
分析了三种截然不同的红外仿真思想,通过这三种方法的对比,提出了一种基于Vega Prime(VP)的红外仿真改进方法。之后在综合经验数据和热平衡模型的基础上,实现了有/无内热源下的坦克红外辐射场分布。同时给出了关键模块的模拟方法。最后... 分析了三种截然不同的红外仿真思想,通过这三种方法的对比,提出了一种基于Vega Prime(VP)的红外仿真改进方法。之后在综合经验数据和热平衡模型的基础上,实现了有/无内热源下的坦克红外辐射场分布。同时给出了关键模块的模拟方法。最后通过三种方法下的仿真实验,模拟出了具有各自代表意义的坦克目标红外图像,通过与实拍红外图像的比较,得出了三种方法的优缺点及适用场合,实验结果真实可靠,有一定的工程应用价值。 展开更多
关键词 VP 红外坦克目标 tmm 2D贴图 顶点着色 面块赋值
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求解二维结构-声耦合问题的一种直接方法 被引量:4
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作者 向宇 黄玉盈 马小强 《振动与冲击》 EI CSCD 北大核心 2003年第4期40-44,31,共6页
本文基于传递矩阵法 (TMM)和虚拟边界元法 (VBEM ) ,提出了一种求解在谐激励作用下二维结构 -声耦合问题的直接法。文中对任意形状的二维弹性环建立了一阶非齐次运动微分方程组 ,便于用齐次扩容精细积分法求解 ,对于含有任意形状孔穴的... 本文基于传递矩阵法 (TMM)和虚拟边界元法 (VBEM ) ,提出了一种求解在谐激励作用下二维结构 -声耦合问题的直接法。文中对任意形状的二维弹性环建立了一阶非齐次运动微分方程组 ,便于用齐次扩容精细积分法求解 ,对于含有任意形状孔穴的无穷域流体介质的Helmholtz外问题 ,采用复数形式的Burton_Miller型组合层势法建立了虚拟边界元方程 ,保证了声压在全波数域内存在唯一解。根据叠加原理并结合最小二乘法 ,提出了一种耦合方程的直接解法 ,由于该方法不存在迭代过程 ,因而具有较高的计算精度和效率。文中给出了二个典型弹性环在集中谐激励力作用下声辐射算例 。 展开更多
关键词 传递矩阵法 tmm 虚拟边界元法 VBEM 微分方程 结构-声耦合问题
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Pipelines vibration analysis and control based on clamps'locations optimization of multi-pump system 被引量:5
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作者 Xin LI Weihao LI +2 位作者 Jian SHI Qiang LI Shaoping WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第6期352-366,共15页
The violent vibration of hydraulic pipelines in aircraft may cause faults or even an accident,especially for the large aircraft with the multi-pump system because of different vibration sources and complex pipelines s... The violent vibration of hydraulic pipelines in aircraft may cause faults or even an accident,especially for the large aircraft with the multi-pump system because of different vibration sources and complex pipelines system.Aiming to the vibration analysis and control of the multipump system,this paper proposed the clamps’locations optimization to minimize the system impedance at vibration frequencies.Firstly,the models of the flexible clamp and other components in multi-pump system were established,based on which,the system impedance was calculated by using Transfer Matrix Method(TMM);Secondly,the objective function is defined as weighted sum of system impedance at frequencies of different vibration sources.Then,the clamps’locations were altered to change the system impedance.Moreover,The Chaotic Swarm Particle Optimization(CPSO)algorithm was applied to obtain the optimal clamps’locations and the minimum value of objective function which decreased by 36.4%compared to the value of original clamps’locations;Finally,the experiments from vibration and pressure test with original and optimized clamps’locations verified the effectiveness of the system impedance calculation and clamps’locations optimization method. 展开更多
关键词 CLAMP CPSO Impedance Multi-pump Pipeline tmm Vibration
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TMM课程体系下大学英语听说课程评估模式构建研究 被引量:2
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作者 刘莉 《湖州师范学院学报》 2014年第3期103-107,共5页
基于TMM课程体系的混元英语教学模式是大学英语听说课程改革的新模式,实施TMM教学体系下大学英语听说课程评估是成功实施此模式的关键。通过调查问卷、访谈、测试和观察方式,得出结论:新的评估模式增强了学生学习英语的自信心与兴趣,培... 基于TMM课程体系的混元英语教学模式是大学英语听说课程改革的新模式,实施TMM教学体系下大学英语听说课程评估是成功实施此模式的关键。通过调查问卷、访谈、测试和观察方式,得出结论:新的评估模式增强了学生学习英语的自信心与兴趣,培养了学生应用学习策略的意识和能力,增强了学生的自主学习能力,学生的英语听说能力也得到了相应的提高。同时发现存在三个问题:部分学生对新的评估模式不适应;学生学习观念滞后于网络环境下学习需要;口语测试评分带有较强主观性。对以上问题进行深度思考后认为,应当进一步完善口语测试评估体系,有计划、有步骤实施形成性评估,建立有效的英语听说教学模式及培养学生在网络环境下自主学习的适应能力。 展开更多
关键词 tmm 大学英语听说课程 评估模式 构建
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TM-JCM法分析FRP-梁界面应力 被引量:1
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作者 刘承 徐荣桥 《低温建筑技术》 2011年第4期42-44,共3页
基于经典梁理论并忽略外贴FRP的抗弯刚度,导出了FRP粘结加固梁的状态方程和传递矩阵。但是由于FRP与混凝土梁的横截面刚度相差太大,导致传统的传递矩阵法(Transfer Matrix Method,TMM)存在比较严重的数值稳定问题。为此,本文在传统的TM... 基于经典梁理论并忽略外贴FRP的抗弯刚度,导出了FRP粘结加固梁的状态方程和传递矩阵。但是由于FRP与混凝土梁的横截面刚度相差太大,导致传统的传递矩阵法(Transfer Matrix Method,TMM)存在比较严重的数值稳定问题。为此,本文在传统的TMM基础上引入节点耦合矩阵法(Joint Coupled Method,JCM)求解状态方程,避免了数值稳定问题,从而得到精确的界面粘结应力。 展开更多
关键词 FRP 状态方程 tmm JCM 粘结剪应力
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Numerical Treatments of Functional Fredholm Integral Equation in 2D with Discontinuous Kernels
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作者 Abeer M. Al-Bugami 《Journal of Applied Mathematics and Physics》 2023年第11期3702-3711,共10页
This work proposes a new definition of the functional Fredholm integral equation in 2D of the second kind with discontinuous kernels (FT-DFIE). Furthermore, the work is concerned to study this new equation numerically... This work proposes a new definition of the functional Fredholm integral equation in 2D of the second kind with discontinuous kernels (FT-DFIE). Furthermore, the work is concerned to study this new equation numerically. The existence of a unique solution of the equation is proved. In addition, the approximate solutions are obtained by two powerful methods Toeplitz Matrix Method (TMM) and Product Nystr?m Methods (PNM). The given numerical examples showed the efficiency and accuracy of the introduced methods. 展开更多
关键词 Functional Integral Equation tmm PNM Hammerstion
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TMM教学体系下大学英语听说课程评估模式对学生产生的影响 被引量:1
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作者 刘莉 《河北联合大学学报(社会科学版)》 2013年第6期202-205,211,共5页
基于TMM课程体系的混元英语教学模式是大学英语听说课程改革的新模式,对TMM教学体系下大学英语听说课程的评估进行实践探索。通过调查问卷、访谈和测试的方式,调查TMM教学体系下大学英语听说课程的评估模式对学生产生的影响。结果表明:... 基于TMM课程体系的混元英语教学模式是大学英语听说课程改革的新模式,对TMM教学体系下大学英语听说课程的评估进行实践探索。通过调查问卷、访谈和测试的方式,调查TMM教学体系下大学英语听说课程的评估模式对学生产生的影响。结果表明:新的评估模式增强了学生学习英语的自信心与兴趣,培养了学生应用学习策略的意识和能力,增强了自主学习能力,学生的英语听说能力也得到了相应的提高。同时提供五点启示:实施口语教学中的形成性评估;提高学生口语学习的自主性;培养学生使用口语自主学习策略;培养学生在网络环境下自主学习的适应能力;增加学生与教师间的互动。 展开更多
关键词 tmm 大学英语听说课程 评估模式 影响分析
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基于宇称-时间对称光子晶体结构的磁场传感器研究 被引量:1
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作者 易凌俊 李长红 《光电子.激光》 CAS CSCD 北大核心 2022年第3期256-263,共8页
提出了一种基于宇称-时间(parity-time,PT)对称结构的磁场检测微腔模型,利用水基Fe_(3)O_(4)磁流体介质层的磁光效应和PT对称结构的光放大效应,当磁场强度发生变化时,引起结构禁带中缺陷模位置的改变。因此,可以通过检测缺陷模位置实现... 提出了一种基于宇称-时间(parity-time,PT)对称结构的磁场检测微腔模型,利用水基Fe_(3)O_(4)磁流体介质层的磁光效应和PT对称结构的光放大效应,当磁场强度发生变化时,引起结构禁带中缺陷模位置的改变。因此,可以通过检测缺陷模位置实现磁场强度的检测。本文利用传递矩阵法(transfer matrix method,TMM)从理论上分析了结构的透射光谱,在此基础上对结构周期、介质层厚度、PT对称单元中宏观洛伦兹振荡强度等参数进行了数值优化。优化后的仿真结果表明,该传感器能够实现有效的磁场磁强检测,磁场强度在0—500Oe的范围内,传感器的灵敏度可以达到97.14nm/RIU,优值和检测极限分别可以达到10^(4)和10^(-7) RIU。同时,传感器的分辨率数值最小可以达到0.05Oe和最大可以达到2Oe。本文所设计的传感器结构可用于高综合性能磁场强度检测设备的设计。 展开更多
关键词 宇称-时间(parity-time PT)对称 磁光效应 传递矩阵(transfer matrix method tmm) 磁场传感器
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Optical properties in 1D photonic crystal structure using Si/C_(60) multilayers 被引量:1
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作者 谌静 唐吉玉 +1 位作者 韩培德 陈俊芳 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2009年第4期7-9,共3页
The feasibility of using Si/C60 multilayer films as one-dimensional (1D) photonic band gap crystals was investigated by theoretical calculations using a transfer matrix method (TMM). The response has been studied ... The feasibility of using Si/C60 multilayer films as one-dimensional (1D) photonic band gap crystals was investigated by theoretical calculations using a transfer matrix method (TMM). The response has been studied both within and out of the periodic plane of Si/C60 multilayers. It is found that Si/C60 multilayer films show incomplete photonic band gap (PBG) behavior in the visible frequency range. The fabricated Si/C60 multilayers with two pairs of 70 nm C60 and 30 nm Si layers exhibit a PBG at central wavelength of about 600 nm, and the highest re?ectivity can reach 99%. As a consequence, this photonic crystal may be important for fabricating a photonic crystal with an incomplete band gap in the visible frequency range. 展开更多
关键词 FULLERENE SI multilayer films photonic band gap tmm method
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Telomeres and Telomerase: Molecular Views and Perspectives 被引量:1
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作者 Kumar Arvind Tony Grace 《Advances in Aging Research》 2018年第5期91-111,共21页
Telomere, the nucleoprotein structure at the end of eukaryotic linear chromosomes is indispensable for maintaining the genome stability. Telomeric DNA loss is apparent with each cell division, which marks an endpoint ... Telomere, the nucleoprotein structure at the end of eukaryotic linear chromosomes is indispensable for maintaining the genome stability. Telomeric DNA loss is apparent with each cell division, which marks an endpoint to the indefinite replication of the cell by causing replicative senescence that may lead to the programmed cell death. The loss of telomere is normal in cell division and as such after 20 - 40 divisions, telomere becomes too short to facilitate the capping function. Telomere uncapping or chromosomal free end causes a potential threat to the genomic stability and thus leads to the accumulation of chromosomal abnormalities that have been known to play a role in aging and cancer. Telomerase, the ribonucleoprotein complex, and its accessory proteins are required to maintain the telomere sequence. Telomerase plays a key role in maintaining the length of telomere by adding G-rich repeat sequences. Its activity has been found to be quite high in the gametes, stem cells and most importantly tumor cells. Almost 85% of tumor cells compensate for telomere loss aided by telomerase-associated protein complex and shelter in complex or telosome. However, 5% - 10% of the cells undergo telomerase-independent mechanism. This review presents the molecular view of the telomere and telomerase along with its associated complex structures. It also discusses its contrasting role in causing cellular senescence and promoting tumorigenesis. 展开更多
关键词 TELOMERE TELOMERASE Aging TUMORIGENESIS tmm SHELTERIN
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Analysis and modeling of ridge waveguide quarterly wavelength shifted distributed feedback laser with three rate equations
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作者 Abbas GHADIMI Alireza AHADPOUR SHAL 《Frontiers of Optoelectronics》 CSCD 2015年第3期329-340,共12页
In this paper, ridge waveguide quarterly wavelength shifted distributed feedback (RW-QWS- DFB) laser was modeled and analyzed. In this behavioral model, some characteristics of the device, such as thresh- old curren... In this paper, ridge waveguide quarterly wavelength shifted distributed feedback (RW-QWS- DFB) laser was modeled and analyzed. In this behavioral model, some characteristics of the device, such as thresh- old current, line width, power of output wave, spectrum of output wave, and laser stability in high powers, were investigated in accordance with different physical and geographical parameters such as sizes and structures of the layers. Considering a new proposed algorithm, the analysis of the mentioned structures was performed using transfer matrix method (TMM), the solution of coupled waves and carrier rate equations. The results showed the advantages of some parameters in this structure. 展开更多
关键词 distributed feedback laser transfer matrixmethod tmm transversal and lateral mode
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Transfer matrix modeling of avalanche photodiode
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作者 Saeed OLYAEE Mohammad SOROOSH Mahdieh IZADPANAH 《Frontiers of Optoelectronics》 2012年第3期317-321,共5页
In this article, we calculated and modeled the gain of Ino.53Gao.47As/[nP avalanche photodiode (APD) based on a device mechanism and carrier rate equations using transfer matrix method (TMM). In fact, a distribute... In this article, we calculated and modeled the gain of Ino.53Gao.47As/[nP avalanche photodiode (APD) based on a device mechanism and carrier rate equations using transfer matrix method (TMM). In fact, a distributed model was presented for calculating impact ionization (I2) and relating different sections of the multiplication region. In this proposed model, recessive equations were used, and device gain is considered proportional to the number of output photo-electrons and photo-holes. By comparison of simulated results with experimental data available in literature, it has been demonstrated the capability of the developed model as a powerful tool for simulating APDs' behavior and interpreting their experimentally measured characteristics. 展开更多
关键词 avalanche photodetector (APD) impact ioni-zation (I2) transfer matrix method tmm
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