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Genetic algorithm assisted meta-atom design for high-performance metasurface optics

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Opto-electronic Science 2024年第9期3卷 15-28页

作者： Zhenjie Yu Moxin Li Zhenyu Xing Hao Gao Zeyang Liu Shiliang pu Hui mao Hong cai Qiang ma Wenqi Ren Jiang Zhu Cheng Zhang school of Optical and electronic{{2.wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Hikvision Research Institute Hangzhou 310051China

Metasurfaces,composed of planar arrays of intricately designed meta-atom structures,possess remarkable capabilities in controlling electromagnetic waves in various ways.A critical aspect of metasurface design involves selecting suitable meta-atoms to achieve target functionalities such as phase retardation,amplitude modulation,and polarization *** design processes often involve extensive parameter sweeping,a laborious and computationally intensive task heavily reliant on designer expertise and ***,we present an efficient genetic algorithm assisted meta-atom optimization method for high-performance metasurface optics,which is compatible to both single-and multiobjective device design *** first employ the method for a single-objective design task and implement a high-efficiency Pancharatnam-Berry phase based metalens with an average focusing efficiency exceeding 80%in the visible *** then employ the method for a dual-objective metasurface design task and construct an efficient spin-multiplexed structural beam *** device is capable of generating zeroth-order and first-order Bessel beams respectively under right-handed and left-handed circular polarized illumination,with associated generation efficiencies surpassing 88%.Finally,we implement a wavelength and spin co-multiplexed four-channel metahologram capable of projecting two spin-multiplexed holographic images under each operational wavelength,with efficiencies over 50%.Our work offers a streamlined and easy-to-implement approach to meta-atom design and optimization,empowering designers to create diverse high-performance and multifunctional metasurface optics.

关键词： metasurface metalens Bessel beam metahologram genetic algorithm

Cluster observations of high-altitude cusp during multiple fast-turning IMF

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Chinese Science Bulletin 2010年第12期55卷 1178-1185页

作者： cai hongtao ma {2. DUNLOP M W BOGDANOVA Y DAVIES J A PITOUT F school of electronic{2. Wuhan University Wuhan 430079 China Key Lab of Geospace Environment and Geodesy CNEM Wuhan 430079 China SSTD Rutherford Appleton Laboratory Chilton OX11 OQX UK Department of Physics La Trobe University Melbourne Victoria 3086 Australia max-Planck-lnstitut fiir Extraterrestrische Physik Garching D-37191 Germany

Using coordinated observations from the Cluster,DMSP and ESR radar,high-altitude cusp was investigated for a time period characterized by four fast reversals of the IMF *** February 12.2.03,Cluster was flying sunward at duskside over the Northern Hemisphere,across the high-altitude northern cusp *** the two crossings are during steady northward IMF interval,whereas ion fluxes detected during the time period are quite *** cusp in the first crossing is a "typical" northward-IMF one,with short-lived ion injections of evident "reversed" dispersion *** the second crossing,however,the cusp appears to be a region reminiscent of the Stagnant Exterior Cusp (SEC).In addition,evident upward-flowing O+ ion bursts,possibly original from polar ionosphere,are also detected during the second cusp crossing,together with enhancement of trapped magnetospheric-like electron *** suggest that the SEC-like cusp is likely on newly closed field lines,which were first reconnected (being opened) at low latitudes and later reconnected again (being closed) poleward of the northern cusp.

关键词：国际货币基金组织高海拔群集观测十字路口离子检测低纬度地区气象卫星

A Localization Method of High Energy Transients for All-sky Gamma-ray Monitor

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Research in Astronomy and Astrophysics 2024年第10期24卷 25-35页

作者： Yi Zhao Wangchen Xue Shaolin Xiong Qi Luo Yuanhao Wang Jiacong Liu Heng Yu Xiaoyun Zhao Yue Huang Jinyuan Liao Jianchao Sun Xiaobo Li Qibin Yi Ce cai Shuo Xiao Shenglun Xie Chao Zheng Yanqiu Zhang Chenwei Wang Wenjun Tan Zhiwei Guo Chaoyang Li Zhenghua An Gang Chen Yanqi Du Min Gao Ke Gong Dongya Guo Jiang He Jianjian He Bing Li Gang Li Xinqiao Li Jing Liang Xiaohua Liang Yaqing Liu Xiang ma Rui Qiao Liming Song Xinying Song Xilei Sun Jin Wang Ping Wang Xiangyang Wen Hong Wu Yanbing Xu Sheng Yang Dali Zhang Fan Zhang Hongmei Zhang Peng Zhang Shu Zhang Zhen Zhang Shijie Zheng Keke Zhang Xingbo Han Haiyan Wu Hu Tai Hao Geng Gaopeng Lu Wei Xu Fanchao Lyu Hongbo Zhang Fangjun Lu Shuangnan Zhang Department of Astronomy Beijing Normal UniversityBeijing 100875China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China school of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China College of Physics Hebei Normal UniversityShijiazhuang 050024China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China school of Physics and electronic Science Guizhou Normal UniversityGuiyang 550001China Institute of Astrophysics Central China Normal UniversityWuhan 430079China College of physics Sciences Technology Hebei UniversityBaoding 071002China Physics and Space Science College China West Normal UniversityNanchong 637002China school of Computing and Artificial Intelligence Southwest Jiaotong UniversityChengdu 611756China College of electronic and information Engineering Tongji UniversityShanghai 201804China Innovation Academy for Microsatellites of Chinese Academy of Sciences Shanghai 201304China National Space Science Center Chinese Academy of SciencesBeijing 100190China school of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China electronic information{2. Wuhan UniversityWuhan 430072China Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210000China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Fast and reliable localization of high-energy transients is crucial for characterizing the burst properties and guiding the follow-up *** based on the relative counts of different detectors has been widely used for all-sky gamma-ray *** are two major methods for this count distribution localization:χ^(2.minimization method and the Bayesian *** we propose a modified Bayesian method that could take advantage of both the accuracy of the Bayesian method and the simplicity of the χ^(2.*** comprehensive simulations,we find that our Bayesian method with Poisson likelihood is generally more applicable for various bursts than the χ^(2.method,especially for weak *** further proposed a location-spectrum iteration approach based on the Bayesian inference,which could alleviate the problems caused by the spectral difference between the burst and location *** method is very suitable for scenarios with limited computation resources or timesensitive applications,such as in-flight localization software,and low-latency localization for rapidly follow-up observations.

关键词： methods:data analysis methods:analytical (stars:)gamma-ray burst:general

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星载光子计数激光雷达海面点云仿真方法

红外与毫米波学报 2020年第4期39卷 483-490页

作者：张文豪李松马跃张智宇赵朴凡武汉大学电子信息学院湖北武汉430072

星载光子计数激光雷达作为一种新的探测体制激光雷达,已开始应用于海面测量。然而受海风等多种因素的影响,海面存在一定的粗糙度和较大的起伏变化,因此光子计数激光雷达返回的信号点云在返回能量和信号光子分布上存在较大的变化,潜在的... 详细信息

星载光子计数激光雷达作为一种新的探测体制激光雷达,已开始应用于海面测量。然而受海风等多种因素的影响,海面存在一定的粗糙度和较大的起伏变化,因此光子计数激光雷达返回的信号点云在返回能量和信号光子分布上存在较大的变化,潜在的影响到了海面高程测量精度。本文基于JONSWAP海浪谱和微面元模型理论,结合蒙特卡洛方法建立了光子计数激光雷达海洋目标的仿真模型。以ICESat-2.载光子计数激光雷达的系统参数作为输入,仿真了不同风速条件下海面的信号光子分布,通过与ICESat-2.测结果对比证明了仿真方法的正确性。基于仿真模型,分析了不同风速条件下,光子计数激光雷达的测距误差分布。结果表明,光子计数激光雷达测得的海面高程小于实际参考海面,且测量偏差和标准差随风速增加而增大,当风速为10m/s,累计脉冲次数为100次时,测量偏差约为-2.5cm,标准差为3.6cm。所建立的仿真模型和分析结果对优化针对海面观测的星载光子计数激光雷达的系统参数设计和平均海面观测结果修正具有重要的参考意义。

关键词：光子计数激光雷达海洋仿真微面元理论误差分析

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同质结钙钛矿太阳能电池性能优化研究

固体电子学研究与进展 2022年第4期42卷 292-298页

作者：李玉霞甘永进覃斌毅李清流蒋曲博毕雪光李璞蔡文峰玉林师范学院物理与电信工程学院广西玉林537000 桂林电子科技大学广西光电信息处理重点实验室广西桂林541004

基于太阳能电池模拟软件SCAPS-1D,设计了结构为FTO/Nb_(2.O_(5)/n型maPbI_(3)/p型maPbI_(3)/CuO/Au的同质结钙钛矿太阳能电池。为达到优化电池性能的目的,探讨了钙钛矿活性层的厚度和缺陷态密度以及载流子传输层和钙钛矿活性层界面的缺... 详细信息

基于太阳能电池模拟软件SCAPS-1D,设计了结构为FTO/Nb_(2.O_(5)/n型maPbI_(3)/p型maPbI_(3)/CuO/Au的同质结钙钛矿太阳能电池。为达到优化电池性能的目的,探讨了钙钛矿活性层的厚度和缺陷态密度以及载流子传输层和钙钛矿活性层界面的缺陷态密度对电池性能的影响。由仿真结果知,适当增加n型maPbI_(3)的厚度可增强对光子的有效吸收从而提升电池性能,但当n型maPbI_(3)的厚度大于载流子扩散长度时,载流子复合增强导致电池性能降低。随着n型maPbI_(3)的缺陷态密度不断增加,相当于引入了更多的载流子复合中心,因此电池性能逐渐变差。相比n型maPbI_(3),由于p型maPbI_(3)置于n型maPbI_(3)的背面,其厚度及缺陷态密度的变化对电池性能影响较弱。随着界面层缺陷态密度的增加,光生载流子运输受到阻碍,复合增强从而限制了电池的性能提升,相比p型maPbI_(3)和CuO之间的界面而言,Nb_(2.O_(5)和n型maPbI_(3)之间的界面缺陷态密度对电池性能影响效果更明显。通过参数优化,提升了电池的输出性能,优化后电池的开路电压、短路电流密度、填充因子及效率分别为1.2. V、2..46ma/cm^(2.、88.35%和2..2.%。

关键词：同质结钙钛矿太阳能电池厚度缺陷态密度界面

中国经自然腔道取标本手术41841例开展现状分析:2.2.年医师调查报告

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中华结直肠疾病电子杂志 2023年第1期12卷 42-49页

作者：关旭焦帅彭健姚宏亮王贵玉何庆泗郑阳春胡军红李太原康亮王振宁蔡建春江波熊治国马丹孙学军丁克峰汪泳周海涛傅传刚王锡山国家癌症中心/国家肿瘤临床医学研究中心/中国医学科学院北京协和医学院肿瘤医院结直肠外科北京100021 哈尔滨医科大学附属第二医院结直肠肿瘤外科 150006 中南大学湘雅医院普外科长沙410008 中南大学湘雅二医院胃肠外科长沙410008 山东大学齐鲁医院胃肠外科济南250012 四川省肿瘤医院胃肠外科成都610041 郑州大学第一附属医院普外科 450052 南昌大学第一附属医院普外科 330000 中山大学附属第六医院结直肠外科广州510655 中国医科大学附属第一医院肿瘤外科沈阳110000 厦门大学附属中山医院胃肠外科 361004 山西省肿瘤医院结直肠肛门外科太原030013 湖北省肿瘤医院胃肠外科武汉430079 第三军医大学新桥医院普通外科重庆400037 西安交通大学第一附属医院普外科 710061 浙江大学医学院附属第二医院大肠外科杭州310009 安徽医科大学第二附属医院普外科合肥230601 同济大学附属东方医院胃肠肛肠外科上海200120

目的了解我国经自然腔道取标本手术(NOSES)开展现状,为NOSES发展提供重要参考依据。方法基于微信问卷形式,针对我国从事普通外科、肿瘤外科、妇科等专业的医师展开调查。调查内容包括医师基本信息、我国NOSES开展情况、NOSES技术培训与... 详细信息

目的了解我国经自然腔道取标本手术(NOSES)开展现状,为NOSES发展提供重要参考依据。方法基于微信问卷形式,针对我国从事普通外科、肿瘤外科、妇科等专业的医师展开调查。调查内容包括医师基本信息、我国NOSES开展情况、NOSES技术培训与科研现状。结果本研究覆盖我国30个省份及地区,共收集12.2.有效问卷调查表,其中开展NOSES医生为833人,占64.5%,未开展NOSES医生为459人,占35.5%。我国开展NOSES的医院共559家,开展NOSES总例数为41841例,其中结直肠肿瘤NOSES为35007例,胃肿瘤NOSES为4381例,其他疾病NOSES为2.53例。根据不同取标本途径分类,经肛门取标本NOSES共3372.例,经阴道取标本NOSES为7676例,经口取标本NOSES为437例。我国开展NOSES课题研究的医师占2..4%;发表NOSES论文的医师占2..2.。关于我国NOSES数据库情况,71.7%的医师未将NOSES数据上传至中国NOSES数据库。对于未来NOSES发展,91.3%的医师建议加强技术规范化培训,72.1%的医师建议向基层医生推广。结论NOSES已在我国全面普及,地域分布广泛。为进一步推进NOSES临床应用,面向基层的规范化培训是医生的迫切需求,也是NOSES未来重要发展方向。

关键词：经自然腔道取标本手术(NOSES) 微创手术问卷调查现状分析