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Mode-switchable dual-color infrared quantum cascade detector

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Photonics Research 2024年第2期12卷 253-259页

作者： yixuan zhu SHENQIANG ZHAI KUN LI KAI GUO QIANGQIANG GUO JINCHUAN ZHANG SHUMAN LIU LIJUN WANG FENGQI LIU JUNQI LIU Key Laboratory of Semiconductor Materials Science Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

In this paper,a patch-antenna-array enhanced quantum cascade detector with freely switchable operating modes among mid-wave,long-wave,and dual-color was proposed and *** dual-color absorption occurs in a single active region through an optimized coupled miniband diagonal-transition subbands arrangement,and a successful separation of the operation regimes was realized by two nested antenna arrays with different patch sizes up to room *** 77 K,the 5.7-μm channel achieved a peak responsivity of 34.6 mA/W and exhibited a detectivity of 2.0×10^(10)Jones,while the 10.0-μm channel achieved a peak responsivity of 87.5 mA/W,giving a detectivity of 5.0×10^(10)*** a polarization modulation of the incident light,the minimum cross talk of the mid-wave and the long-wave operating modes was 1:22.5 and 1:7.6,*** demonstration opens a new prospect for multicolor infrared imaging chip integration technology.

关键词： antenna polarization quantum

外出打工率对农户教育支出的影响--基于人力资本投资激励效应

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人口学刊 2024年第5期46卷 17-33页

作者：梁辉朱奕璇冯恩亮中南财经政法大学公共管理学院湖北武汉430073

人力资本成为中国农村实现新质生产力发展的关键因素,然而人口流失又是短期内不会改变的趋势,因此我们需要思考的是农村如何在人口规模减少的背景下实现人力资本积累。文章从微观农户的视角分析当村庄外出打工率增加时,农户是否会由于... 详细信息

人力资本成为中国农村实现新质生产力发展的关键因素,然而人口流失又是短期内不会改变的趋势,因此我们需要思考的是农村如何在人口规模减少的背景下实现人力资本积累。文章从微观农户的视角分析当村庄外出打工率增加时,农户是否会由于未来迁出就业的高回报而加大对子女的教育支出,这既是对人力资本投资激励效应的理论完善,也为农村实现人力资本积累提供了路径思考。本文基于2010年和2014年中国家庭追踪调查(CFPS)数据库的两期追踪儿童数据构建带有调节变量的中介效应模型,验证人力资本投资激励效应在中国农村的存在性、发生条件与影响机制。实证分析发现:只有在村庄外出打工率超过43.54%、家庭收入超过3.994万元之后,人力资本投资激励效应才会显著,即村庄外出打工率促进农户教育支出。该结论在考虑样本选择的干扰、迁移原因的干扰以及抽样数据可靠性的干扰后依然稳健。当纳入父母教育期望这一影响机制时,人力资本投资激励效应的条件被拓宽,村庄外出打工率的拐点从43.54%下降到37.65%。再加入调节变量之后机制更加清晰,母亲的人缘关系指代的家庭信息接收能力作为调节变量,发挥了直接调节作用和对中介效应第一阶段的间接调节作用。人均村务布告栏数量指代的村庄信息传输通畅程度作为另一调节变量,也同样发挥了直接调节作用。进一步的异质性分析发现迁出率急剧增长的村庄中的人力资本投资激励效应最明显,反映出外部环境的动态变化对人们心理影响更大。在地区分布上,只有中部地区的农村存在显著的人力资本投资激励效应,而东部地区和西部地区的这一作用并不显著。因此,对于人口流失的中国农村而言,要实现人力资本积累,应当在发展非农产业提升农民收入的同时注重完善村庄信息传输渠道、鼓励城乡交流、提升农民教育期望。

关键词：外出打工率教育期望人力资本投资激励效应农户教育支出

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论弗雷格《算术基础》中的语境原则

西部学刊 2024年第7期 43-46页

作者：朱奕璇浙江理工大学杭州311199

弗雷格在《算术基础》中提出“语境原则”,并将其作为重要的方法论原则指导他关于“数”的论证。从对比和联系中理解弗雷格的语境原则:弗雷格的语境原则与语用学研究中的语境方法在研究对象、研究范围和研究方法上存在差异;该书序言中... 详细信息

弗雷格在《算术基础》中提出“语境原则”,并将其作为重要的方法论原则指导他关于“数”的论证。从对比和联系中理解弗雷格的语境原则:弗雷格的语境原则与语用学研究中的语境方法在研究对象、研究范围和研究方法上存在差异;该书序言中的三条原则相互联系,语境原则是对一、三条原则的保证。《算术基础》对语境原则的具体运用体现在以下三方面:首先表现为弗雷格对经验主义者、主观主义者关于“数”的观点的批判;其次他重视分析句子中的定冠词,以定冠词的有无来区分专名与概念词,并支撑自己对他人观点的反驳;最后弗雷格讨论数相等意义的出发点以及对休谟原则的解释也是对语境原则的遵循。

关键词：弗雷格《算术基础》语境原则

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基于硫铟锌纳米花的被动调Q激光

光学学报 2024年第4期44卷 247-253页

作者：朱宜璇仝鲁阳蔡阳健赵丽娜郑立仁山东师范大学物理与电子科学学院光场调控及应用中心山东省光学与光子器件技术重点实验室山东济南250358 华东师范大学与山东师范大学光调控科学与光子集成芯片联合研究中心上海200241

采用溶液法合成了二维硫铟锌纳米花,并测量了其可饱和吸收参数,其中,饱和强度为675 MW/cm^(2),调制深度为7.8%。通过搭建1μm全固态激光器,获得最大输出功率为240 mW、最大重复频率为629.08 kHz、最小脉冲宽度为388 ns、相应的单脉冲能... 详细信息

采用溶液法合成了二维硫铟锌纳米花,并测量了其可饱和吸收参数,其中,饱和强度为675 MW/cm^(2),调制深度为7.8%。通过搭建1μm全固态激光器,获得最大输出功率为240 mW、最大重复频率为629.08 kHz、最小脉冲宽度为388 ns、相应的单脉冲能量为0.38μJ、峰值功率为0.98 W的脉冲激光。结果表明,由于硫空位的存在,硫铟锌纳米花能够吸收能量低于其带宽的光子,在近红外区域,表现出良好的可饱和吸收特性,且在激光器中,能够获得高重复频率和短脉冲宽度的激光输出。因此,基于硫铟锌纳米材料的可饱和吸收体在调Q脉冲激光器中具有广阔的应用前景。

关键词：非线性光学脉冲激光可饱和吸收体二维材料硫空位硫铟锌

维生素摄入量与代谢相关脂肪性肝病进程的相关性分析

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实用医学杂志 2024年第6期40卷 820-826页

作者：姚仁玲朱艺璇黄睿李婕南京大学医学院附属鼓楼医院感染科南京210008 南京医科大学鼓楼临床医学院感染科南京210008

目的探讨膳食多种维生素摄入量与代谢相关脂肪性肝病(metabolic dysfunction-associated fatty liver disease, MAFLD)个体肝纤维化风险及全因死亡率之间的相关性。方法从美国第三次国家健康和营养检查调查(National Health and Nutri... 详细信息

目的探讨膳食多种维生素摄入量与代谢相关脂肪性肝病(metabolic dysfunction-associated fatty liver disease, MAFLD)个体肝纤维化风险及全因死亡率之间的相关性。方法从美国第三次国家健康和营养检查调查(National Health and Nutrition Examination Surveys,NHANES)中获取相关数据,并采用24 h饮食回顾法评估膳食维生素摄入情况,包括维生素A、维生素B1、维生素B6、维生素B12、维生素C、维生素D、核黄素、叶酸和α-生育酚。非酒精性脂肪性肝病纤维化评分(non-alcoholic fatty liver disease fibrosis score,NFS) 11.5 mg/d)的纤维化风险明显低于摄入量最低四分位数组(P=0.031)。与VC摄入量最低四分位数组相比,最高四分位数组(> 130 mg/d)的死亡率降低了0.34倍(HR:0.66, 95%CI:0.51~0.85, P=0.001)。结论摄入更多α-生育酚可减轻MAFLD个体的纤维化,摄入更多VC可降低MAFLD个体的全因死亡率。

关键词：代谢相关脂肪性肝病肝纤维化死亡率维生素

Gottfried Konecny:our best friend in photogrammetry and remote sensing of China

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Geo-Spatial Information Science 2021年第1期24卷 5-7,I0002页

作者： Deren Li yixuan zhu Lite Shi State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina

Preface Lebenslauf ***.-*** Gottfried Konecny is one of the most respected names in *** is an Honorary Member of International Society for Photogrammetry and Remote Sensing(ISPRS),Honorary Professor of Wuhan Technical... 详细信息

关键词： gramme ISPRS Remote

Improving pseudo-labeling with reliable inter-camera distance encouragement for unsupervised person re-identification

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Science China(Information Sciences) 2023年第5期66卷 88-99页

作者： Yiyu CHEN Zheyi FAN Shuni CHEN yixuan zhu School of Information and Electronics Beijing Institute of Technology

Unsupervised person re-identification(re-ID) aims to train a discriminative model without identity annotations. State-of-the-art methods usually follow a clustering-based pipeline, which utilizes a clustering algorithm to generate pseudo-labels and performs model training iteratively. Despite the success of these methods, camera variation has not been well considered in the distance calculation step to reduce noise labels, which is the main reason for noise label generation. To address this problem, we design a plug-and-play method with low computational complexity to improve the distance calculation step in the pseudo-label generation stage. Specifically,(1) to alleviate the influence of intra-camera samples and select reliable inter-camera pairs, we propose inter-camera k-reciprocal nearest neighbor(IKNN) to mine reliable inter-camera positive pairs; and(2) to merge the relationship of reliable inter-camera pairs into the distance for better clustering, we design adaptive inter-camera encouragement(AIE) to encourage the distance of inter-camera positive pairs. Extensive experiments show consistent improvements in comparison with various state-of-the-art unsupervised re-ID methods, demonstrating the wide applicability and efectiveness of our method.

关键词： person re-identification noise label camera variation clustering deep learning

Current status and future directions of the Tibetan Plateau ecosystem research

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Science Bulletin 2019年第7期64卷 428-430页

作者： Yangjian Zhang yixuan zhu Junxiang Li Yao Chen Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

The Tibetan Plateau (TP) encompasses Xizang and Qinghai and parts of northern Yunnan and Sichuan provinces, with a total area of circa 2.6 millions km2. The 2013 satellite data showed that grasslands, forests, wetlands, agricultural lands, and deserts account for 60%, 7.7%, 1.4%, 0.3%, and 30%, respectively, of total TP land (1)Due to its existence in dry, high altitude and cold environments, the TP ecosystem is extremely vulnerable to global climate change and studies on the TP ecosystem can be utilized as a pre-warning for other ecosystems.

关键词： Current status and future directions of the Tibetan Plateau ecosystem research TP

TECHNIQUES OF 3D COMPONENT DATABASE ESTABLISHING AND QUALITY CONTROL FOR WOODEN BUILDING

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Geo-Spatial Information Science 2001年第3期4卷 73-77页

作者： XU Miaozhong zhu yixuan National Laboratory for Information Engineering in Surveying Mapping and Remote Sensing Wuhan University

Based on the architectural survey project of "the Chi Lin Nunnery Redevelopment "in Hong Kong,this paper attempts to investigate the techniques of building 3D digital document of large_scale timber structure and quality control during construction by computer_based 3D simulation for the whole *** were several key issues including primary data acquisition,3D modeling and display,pre_assembling the total building and quality examination,*** this paper,some useful experiments,such as the new applications of CCD digital cameras,image and graph processing software packages (CAD,Photoshop,Photomodeler,Vexcel,etc.) to the architectures are also *** methods introduced in this paper are suitable for image and graph integrated database building of complicated architectures,and useful for conveniently maintaining and reconstructing the ancient architectures.

关键词： component database quality control CAD