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Periodicity Characteristic of TOAD's Switching Window

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Chinese Journal of Lasers 2000年第2期9卷 161-166页

作者： liu xianbing,YE Peida (Beijing University of Posts and Telecommunications, Beijing 100876, China ) 北京邮电大学北京

The periodidity characteristic of switching window of a terahertz optical asymmetric demultiplexer (TOAD) using numerical simulation was investigated. The results show that the switching window width of TOAD changes periodically with the time asymmetry of TOAD and the period is one half of the period of control pulses. The theoretical results agree with the experimental results very well.

关键词： terahertz optical asymmetric demultiplexer (TOAD) Sendconductor optical amplifier (SOA) optical time division multiplexing (OTDM)

Analyzing the Switching Characteristics of a NOLM Demultiplexer with on Analytic and Numrical Methods

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Chinese Journal of Lasers 1999年第5期8卷 419-424页

作者： liu xianbing YE Peida(Telecommunications Engineering School, Beijing University of Posts and Telecommunications, Beijing 100876 China) 北京邮电大学电信工程学院北京

The switching characteristics of a NOLM demultiplexer are investigated by using an analytic and numerical method. The results reveal that the switching characteristics of a NOLM demultiplexer depend on parameters such as the power coupling ratio of the coupler,the peak power of control pulses, the walk-off and the initial time delay between signal pulses and control pulses, etc. The efficiency of NOLM is dependent on the peak power of controlpulses However, the switching window profile begins to oscillate as the power exceeds a critica value and this will be detrimental to the demultiplexed signals. The signal-control pulse walk-off can broaden the switching window of NOLM, make the window profile deviate fromits central position, and decrease its switching efficiency.

关键词： OTDM NOLM demultiplexer all-optical switch

A numerical study for the coastal upwelling and the coastal front off Zhejiang coast

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Acta Oceanologica Sinica 1990年第4期9卷 499-512页

作者： liu xianbing and Su Jilan Second Institute of Oceanography, State Oceanic Administration, Hangzhou, China

A two-dimensional numerical model is constructed to study the interaction between the coastal upwelling and the coastal front off Zhejiang coast in summer. In the f-plane model, the shelf topography, continuous stratification, and Richardson number-dependent eddy coefficients are considered. The results show that the coastal up-welling off Zhejiang in summer can be divided into two regions, the nearshore one (Region A) and the offshore one (Region B). In Region A, the alongshore wind stress has more important effect on the coastal upwelling while in Region B, the upwelling is mainly induced by the Taiwan Warm Current. The results also suggest that the formation of coastal front off Zhejiang in summer is closely related to the strength of the coastal upwelling in Region A.

关键词： A numerical study for the coastal upwelling and the coastal front off Zhejiang coast

光时分复用(OTDM) 系统中基于电吸收调制器(EAM) 的短脉冲光源及解复用器的设计考虑(英文)

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光子学报 1999年第12期28卷 1096-1101页

作者：刘贤炳叶培大北京邮电大学 125信箱北京100876

研究了电吸收调制器（ＥＡＭ）的衰减随外加反向电压增加而指数增加的情形下，短脉冲光源的脉冲输出和解复用器的开关窗口对ＥＡＭ的消光效率、反向ＤＣ偏置电压以及正弦ＲＦ驱动信号的幅度等参量的依赖关系－在基于ＥＡＭ的短脉... 详细信息

研究了电吸收调制器（ＥＡＭ）的衰减随外加反向电压增加而指数增加的情形下，短脉冲光源的脉冲输出和解复用器的开关窗口对ＥＡＭ的消光效率、反向ＤＣ偏置电压以及正弦ＲＦ驱动信号的幅度等参量的依赖关系－在基于ＥＡＭ的短脉冲光源中，输出脉冲的消光比等于ＥＡＭ消光效率η与正弦驱动电压峰峰值Ｖｐｐ的乘积，输出光脉冲的消光比和脉宽均与ＥＡＭ的反向偏置电压无关，但输出脉冲的峰值功率与η、Ｖｐｐ和Ｖｂ都有关系－在基于ＥＡＭ的解复用器中，为了使解复用器的开关窗口近似为矩形，可利用ＥＡＭ的削波效应，使Ｖｐｐ／２＞Ｖｂ－在ＥＡＭ的消光效率η已知时，通过仔细设计反向ＤＣ偏置电压Ｖｂ和正弦驱动电压的峰峰值Ｖｐｐ，达到ＯＴＤＭ解复用器所需要的开关窗口形状、宽度和消光比－

关键词：电吸收调制器光时分复用光通信短脉冲光源

4×10Gbit/s光时分复用(OTDM)系统中基于电吸收调制器(EAM)的光分插复用器

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高技术通讯 2000年第9期10卷 27-31页

作者：刘贤炳叶培大北京邮电大学电信工程学院北京100876

提出了一种光时分复用 (OTDM )系统中完全基于电吸收调制器的光分插复用器(O ADM ) ,该复用器具有简单的结构和灵活上下话路的能力。然后对实现这种O ADM所需要的关键技术进行了分析和讨论。

关键词：电吸收调制器光时分复用光分插复用器光纤通

10Gbit/s高速串行通道的Hspice仿真研究

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光通信研究 2008年第5期 4-5,9页

作者：廖骞刘贤炳光纤通信技术和网络国家重点实验室烽火通信科技股份有限公司湖北武汉430074

随着光传输技术的飞速发展,信号传输速率已经突破Gbit/s级,高速通道的仿真分析已成为系统开发成功与否的关键一环。文章简要介绍了Hspice仿真的基本原理和基本方法,并详细讨论了基于Hspice软件的高速串行通道仿真方法,通过仿真眼图的对... 详细信息

随着光传输技术的飞速发展,信号传输速率已经突破Gbit/s级,高速通道的仿真分析已成为系统开发成功与否的关键一环。文章简要介绍了Hspice仿真的基本原理和基本方法,并详细讨论了基于Hspice软件的高速串行通道仿真方法,通过仿真眼图的对比结果说明影响高速通道性能的几个关键环节以及改善通道特性的方法。

关键词： Hspice仿真眼图高速串行通道

Changes of human decidual natural killer cells cocultured with YFP-Toxoplasma gondii:implications for abnormal pregnancy

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Decidual macrophage M1 polarization contributes to adverse pregnancy induced by Toxoplasma gondii infection

第八届全国免疫学学术大会

作者： Xiaoyan Xu Qiang Fu Qun Zhang Mingdong Zhao Zonghua Gao xianbing liu Yang liu Xuemei Hu Department of Immunology Binzhou Medical University

Background:Toxoplasma gondii could cause abnormal pregnancy *** fetal-maternal interface decidual NK cells play an important in pregnancy in maitain ***, whether disturbance of maternal NK immune tolerance to the fetus could result in the high incidence of abnormal pregnancies observed in mothers infected with *** is not clear up to ***:To investigate the changes of human decidual natural killer(d NK) cells co-cultured with Toxoplasma gondii in vitro and to infer implications on *** Outcome Measure(s):d NK cells were isolated and infected with YFP-Toxoplasma gondii(***).Cells were observed by fluorescence and confocal *** CD56brightCD16-/CD56dimCD16+ d NK ratio, expression of KI R2DL4, ILT-2, and NKG2 D on d NK cells were analyzed by flow cytometry and the cytotoxic activity of infected d NK cells were ***(s):The CD56brightCD16-/CD56dimCD16+d NK ratio was significantly decreased at 12 h(8.51+1.32 vs.2.79+0.67, p=0.0371), 24 h(7.44+2.43 vs.2.48+0.32, p=0.0136), and 48 h(6.65+1.95 vs.2.12+1.08, p=0.0027) following *** *** of KI R2DL4(12h:36.40%+2.41% vs.21.64%+1.92%, p=0.0276;24h:43.52%+1.51% vs.21.64%+1.92%, p=0.0074;48h:58.00%+2.49% vs.21.64%+1.92%, p=0.0024), ILT-2(12h:33.54%+2.34% vs.18.17%+1.37%, p=0.0319;24h:47.05%+2.57% vs.18.17%+1.37%, p=0.0069;48h:58.27%+2.33% vs.18.17%+1.37%, p=0.0018), and NKG2D(12h:39.42%+2.24% vs.26.94%+2.52%, p=0.0366;24h:60.41%+3.11% vs.26.94%+2.52%, p=0.0021;84.26%+4.99% vs.26.94%+2.52%, p=0.0006) were increased after infection, but NKG2 D were significantly higher than those of KI R2DL4 and *** cytotoxic activity was increased after infection with ***(12h:26.72%+8.34% vs.20.87%+9.19%, p=0.0146;24h:31.16%+9.22% vs.21.82%+8.07%, p=0.0115;48h:38.00%+5.29% vs.20.00%+8.23%, p=0.0069).Both the CD56dimCD16+/CD56brightCD16- d NK ratio and NKG2 D expression were correlated with d NK cytotoxic activity(r2 =0.753, p < 0.05 and r2

关键词： YFP-Toxoplasma gondii decidual NK cells abnormal pregnancy outcome

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Decidual macrophage M1 polarization contributes to adverse p...

高速及超高速磨削加工参数V_s的绿色度评价

第十二届全国免疫学学术大会

作者： liu xianbing Jiang Mengqi Ren Liqin Zhang Aihong Zhao Mingdong Zhang Haixia Jiang Yuzhu Hu Xuemei Binzhou Medical University

Recent evidence indicates that macrophages at the maternal-fetal interface adapt to a phenotype characterized by alternative activation(M2 polarization) and exhibit immunosuppressive functions that favor the maintenance of *** bias of M2 decidual macrophages toward M1 has been clinically linked to pregnancy-related complications,such as preeclampsia,and preterm *** aim of this study was to investigate the effect of Toxoplasma gondii infection on the bias of decidual macrophage polarization and its contribution to adverse pregnancy outcomes.A mouse model with adverse pregnancy outcome was established by infection with *** PRU *** expression levels of CD80,CD86,CD206,MHC-Ⅱ,iNOS,arginase-1,IL-10,TNF-α,and IL-12 in decidual macrophages of infection and control mice were *** results showed that the expression of CD206,MHC-Ⅱ,and arginase-1 considered as M2 markers was decreased in decidual macrophages after *** infection,whereas the expression of CD80,CD86,iNOS,and cytokines TNF-α and IL-12 considered as M1 markers was *** results indicated that *** infection was responsible for the bias of M2 decidual macrophages toward M1,which changes the immunosuppressive microenvironment at the maternal-fetal interface and contributes to adverse pregnancy outcomes.

关键词： Toxoplasma gondii decidual macrophages polarization adverse pregnancy outcomes

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现代制造工程 2003年第3期 7-10页

作者：廖兰刘先斌重庆市沙坪坝先锋街重庆工商大学机械系 400033

高速及超高速磨削加工工艺方法是一种具有明显绿色特征的制造工艺方法 ,通过对磨削加工中的一个重要参数———砂轮速度Vs在各个区域内的绿色度值的评价。

关键词：超高速磨削砂轮速度绿色度高速磨削