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Low-loss and polarization insensitive 32×4 optical switch for ROADM applications

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Light(Science & Applications) 2024年第5期13卷 875-884页

作者： Xiaotian Zhu Xiang Wang Yanlu Huang Liyan Wu Chunfei Zhao Mingzhu Xiao Luyi Wang Roy davidson Yanni Ou Brent E.Little Sai T.Chu Department of Physics City University of Hong KongTat Chee AvenueHong KongChina. QXP Technologies Inc. NO.15th Shanglinyuan 1st RoadXi’anShaanxi 710119China. State Key Laboratory of Information of Photonics and Optical Communications School of Electronic EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China

Integrated switches play a crucial role in the development of reconfigurable optical add-drop multiplexers(ROADMs)that have greater flexibility and compactness,ultimately leading to robust single-chip *** decades of research on switches with various structures and platforms,achieving a balance between dense integration,low insertion loss(IL),and polarization-dependent loss(PDL)remains a significant *** this paper,we propose and demonstrate a 32×4 optical switch using high-index doped silica glass(HDSG)for ROADM *** switch is designed to route any of the 32 inputs to the express ports or drop any channels from 32 inputs to the target 4 drop ports or add any of the 4 ports to any of the 32 express *** switch comprises 188 MachZehnder Interferometer(MZI)type switch elements,88 optical vias for the 44 optical bridges,and 618 waveguidewaveguide crossings with three-dimensional(3D)*** 1550 nm,the fiber-to-fiber loss for each express channel is below 2 dB,and across the C and L bands,below 3 *** each input channel to all 4 drop/add channels at 1550 nm,the loss is less than 3.5 dB and less than 5 dB across the C and L *** PDLs for all express and input channels to the 4 drop/add channels are below 0.3 dB over the C band,and the crosstalk is under−50 dB for both the C and L bands.

关键词： polarization ROADM optical

粉末冶金Al-5.6Zn-2Mg合金在热压缩过程中加工硬化特性及本构模型的比较

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Journal of Central South University 2024年第2期31卷 346-368页

作者： KATIKA Harikrishna DAMODA R.K. davidson M.J. SEETHARAM R. KASAGANI Veera Venkata Nagaraju Department of Mechanical Engineering National Institute of TechnologyWarangal 506004India Department of Mechanical Engineering The Indian Institute of Information Technology Design and ManufacturingKurnool 518007India

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的... 详细信息

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的相关性。使用了四个本构模型,Arrhenius模型、改进的Johnson-Cook模型(MJC)、改进的Zerilli-Armstrong模型(MZA)和开发的人工神经网络(ANN)。结果表明,ANN型模型和Arrhenius模型的相对误差的绝对平均值最低,分别为0.486%和3.36%,MZA型模型和MJC型模型的相对误差的绝对平均值较高,分别为8.84%和3.93%。由于Arrhenius模型能够处理各种因素之间的非线性关系,因此它被认为是最合适的预测模型,但在材料性质未知或实验数据有限的情况下,MJC模型可能是一种更简单的替代方法。MZA模型不适合估计热压缩时的流变应力。此外,训练最好的神经网络模型的预测性能最好,相对误差的绝对平均值为0.486%,R值为0.99。

关键词：加工硬化速率曲线本构建模热压缩 EBSD分析流变曲线

The regulatory genome

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丛书名：科爱传播.

2007年

作者： davidson Eric H.

"导读版."

ISBN: (纸本)9787900224026

"导读版."

关键词： Gene Expression Regulation.

Are there sex-based disparities in cataract surgery?

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 137-143页

作者： Matthew D.Geiger Anne M.Lynch Alan G.Palestine Nathan C.Grove Karen L.Christopher Richard S.davidson Michael J.Taravella Naresh Mandava Jennifer L.Patnaik Department of Ophthalmology University of Colorado School of MedicineAuroraCO 80045USA

AIM:To investigate sex-based differences in the occurrence of intra-operative and post-operative complications and associated visual outcomes following cataract ***:This was a retrospective study of patients who had phacoemulsification cataract surgery at the University of Colorado School of *** collected included the patient’s health history,ocular comorbidities,operative and post-operative complications,and the post-operative best corrected visual acuity(BCVA).The data were analyzed using univariate and multivariable logistic regression with generalized estimating equations to account for the correlation of some patients having two eyes included in the ***:A total of 11977 eyes from 7253 patients were included in the *** comorbidities differed by sex,with males having significantly higher percentages of traumatic cataracts(males 0.7%vs females 0.1%),prior ocular surgery(6.7%vs 5.5%),and mature cataracts(2.8%vs 1.9%).Conversely,females had significantly higher rates of pseudoexfoliation(2.0%vs 3.2%).In unadjusted analysis,males had higher rates of posterior capsular rupture(0.8%vs 0.4%)and vitreous loss(1.0%vs 0.6%),but this difference was not significant after adjustment for *** had a significantly increased risk of post-operative retinal detachment,but in multivariable analysis this was no longer *** were significantly less likely to undergo post-operative neodymium-doped yttrium aluminum garnet(Nd:YAG)laser capsulotomy for posterior capsule opacification(OR=0.8,95%CI=0.7-0.9,P=0.0005).The BCVA was slightly worse for males pre-operatively;but post-operatively,both sexes exhibited similar visual acuity of Snellen equivalent 20/***:The study finds that in a cohort of patients presenting for cataract surgery,sex differences exist in pre-operative comorbidities and surgical characteristics that contribute to higher rates of some complications for ***,observed surgical complicatio

关键词： cataract surgery sex-based disparity phacoemulsification outcomes

Nation of nations a narrative history of the American Republic 4th ed. 4th ed.

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2001年

作者： James West davidson

Nation of nations : 5th ed.

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2004年

作者： James West davidson ... [et al.].

Map on lining papers.

ISBN: (纸本)0072870982

Map on lining papers.

关键词： United States

Nation of nations : a concise narrative of the American republic / 3rd ed. 3rd ed.

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2002年

作者： James West davidson ... [et al.].

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节日贺卡

中学生英语 2024年第11期 16-19页

作者： Jacqueline davidson Kopito 梁小明(译) 不详湖北武汉电力职业技术学院

那是离假期还有两周的时候,我还没有寄出我的节日贺卡。每年,我家都会从朋友那里收到几十张节日贺卡,那年我也想寄一张。我们会收到各种各样的贺卡,比如全家的照片、孩子的照片、度假照片,甚至是专业制作的照片。有时我们收到的贺卡上... 详细信息

那是离假期还有两周的时候,我还没有寄出我的节日贺卡。每年,我家都会从朋友那里收到几十张节日贺卡,那年我也想寄一张。我们会收到各种各样的贺卡,比如全家的照片、孩子的照片、度假照片,甚至是专业制作的照片。有时我们收到的贺卡上根本没有图片,只是用明亮、粗体的字母祝我们节日快乐。经过思考,我决定选择专业摄影师拍摄的全家福。把我的两个儿子送到学校后,我打电话预约了当地的摄影师。

关键词：专业摄影师贺卡照片打电话

Nation of nations : a narrative history of the American republic 5th ed.

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2005年

作者： James West davidson ... [et al.].