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Optoelectronics Letters 2024年第3期20卷 171-176页

作者： SUN Jiaxing LI Honglian yao yuhang YAN Qiongyan DONG Fang College of Quality and Technology Supervising Hebei UniversityBaoding 071000China National and Local Joint Engineering Center of Measuring Instruments and Metrology Systems Baoding 071000China Key Laboratory of Energy Measurement and Safety Detection Technology in Hebei Province Baoding 071000China

The origin of Angelica dahurica medicinal herbs varies, and their pharmacological effects also differ. In order to achieve rapid and accurate identification of the origin of Angelica dahurica medicinal herbs, this study utilizes laser induced breakdown spectroscopy(LIBS) technology combined with machine learning algorithms to identify the original source of Angelica dahurica. Sliced samples of Angelica dahurica were taken from four regions: Hebei, Henan, Zhejiang, and Sichuan. The spectral data from the sliced samples were used as features, and different algorithms including support vector machine(SVM), back propagation(BP) neural network, genetic algorithm-back propagation(GA-BP) neural network, particle swarm optimization-back propagation(PSO-BP) neural network, convolutional neural network(CNN), and CNN-SVM were employed to classify the origin of Angelica dahurica samples.

关键词： neural origin network

人工智能辅助孤独症早期诊断和干预的技术路径与未来图景

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中国特殊教育 2024年第3期 81-88页

作者：谢超香姚宇航杜燕凡广西师范大学教育学部桂林541004

孤独症的早诊断和早干预有助于改善症状,帮助患者尽早融入社会。传统的诊断和干预方法依赖于相关人士的专业性,需要大量的时间和精力,人工智能方法有助于早期诊断并提高干预效率。人工智能已广泛应用于孤独症的行为诊断、放射组学和基... 详细信息

孤独症的早诊断和早干预有助于改善症状,帮助患者尽早融入社会。传统的诊断和干预方法依赖于相关人士的专业性,需要大量的时间和精力,人工智能方法有助于早期诊断并提高干预效率。人工智能已广泛应用于孤独症的行为诊断、放射组学和基因诊断及社区筛查服务,也应用于孤独症的教育干预、社交干预,帮助提高该群体的社区生活质量,但目前还存在信息安全缺少保障,干预效果难以迁移和应用范围有限,机器人设计有待提高等问题。未来研究需要建立大型安全可共享的孤独症数据库,增强习得技能的迁移和泛化,提升辅助机器人的外观和性能。

关键词：人工智能孤独症诊断干预

考虑国际金融风险影响的上证50ETF期权定价研究

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运筹与管理 2024年第6期33卷 207-213页

作者：孙有发姚宇航龚翼山邱梓杰刘彩燕广东工业大学经济学院广东广州510520 广东工业大学管理学院广东广州510520

近年来如何刻画国际金融风险对中国市场的影响,成为学术界的热门热点之一。已有文献大多集中于研究国际股票市场之间的风险溢出效应,较少关注国际股票市场对中国期权市场的风险外溢效应。本文将标普500ETF走势嵌入上证50ETF的收益率过程... 详细信息

近年来如何刻画国际金融风险对中国市场的影响,成为学术界的热门热点之一。已有文献大多集中于研究国际股票市场之间的风险溢出效应,较少关注国际股票市场对中国期权市场的风险外溢效应。本文将标普500ETF走势嵌入上证50ETF的收益率过程,构建IFR_BS模型(BS Model with the Impact of International Financial Risk);然后应用特征函数微扰法和Fourier-Cosine定价方法,推导出该模型下欧式期权的近似解析定价公式。数值实验和实证结果表明:(1)IFR_BS模型可以较好地刻画上证50ETF收益率分布的“尖峰”、“肥尾”和“有偏”等统计特征。(2)考虑国际金融风险溢价的IFR_BS模型下的期权定价公式,可以解决BS模型对短到期期权尤其是短到期深度OTM期权估值不足的问题。

关键词：期权定价国际金融风险欠阻尼函数特征函数微扰法 Fourier-Cosine方法

维普期刊数据库博看期刊

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驱动机构活塞杆断裂分析及工艺优化

山西冶金 2024年第1期47卷 60-63页

作者：姚宇航杜冲桂秦锋袁龙湖南云箭集团有限公司湖南长沙410100

针对某次翼片展开试验中驱动机构活塞杆出现断裂的情况,对活塞杆逐步进行了实验检测、仿真复现、工艺分析及优化验证,明确了活塞杠发生断裂的原因。结果表明,断裂是由于40Cr热处理工艺不到位导致了活塞杆心部与表面硬度差距过大,从而导... 详细信息

针对某次翼片展开试验中驱动机构活塞杆出现断裂的情况,对活塞杆逐步进行了实验检测、仿真复现、工艺分析及优化验证,明确了活塞杠发生断裂的原因。结果表明,断裂是由于40Cr热处理工艺不到位导致了活塞杆心部与表面硬度差距过大,从而导致实际强度不足,在高应力冲击下活塞杆最薄弱位置发生了拉伸断裂。对产品工艺、检验方法进行优化改进,采用亚温淬火工艺进行热处理,可有效解决该问题。

关键词：活塞杆拉伸断裂驱动机构数值模拟工艺优化

Low-dimensional van der Waals materials for linear-polarization-sensitive photodetection: materials, polarizing strategies and applications

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Materials Futures 2024年第1期3卷 95-127页

作者： yuhang Ma Huaxin Yi Huanrong Liang Wan Wang Zhaoqiang Zheng Jiandong yao Guowei Yang State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterSchool of Materials Science&EngineeringSun Yat-sen UniversityGuangzhou 510275GuangdongPeople’s Republic of China Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Sun Yat-sen UniversityGuangzhou 510275GuangdongPeople’s Republic of China School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006GuangdongPeople’s Republic of China

Detecting light from a wealth of physical degrees of freedom(***,intensity,polarization state,phase,etc)enables the acquirement of more comprehensive *** the past two decades,low-dimensional van der Waals materials(vdWMs)have established themselves as transformative building blocks toward lensless polarization optoelectronics,which is highly beneficial for optoelectronic system *** review provides a comprehensive overview on the recent development of low-dimensional vdWM polarized *** begin with,the exploitation of pristine 1D/2D vdWMs with immanent in-plane anisotropy and related heterostructures for filterless polarization-sensitive photodetectors is ***,we have systematically epitomized the various strategies to induce polarization photosensitivity and enhance the degree of anisotropy for low-dimensional vdWM photodetectors,including quantum tailoring,construction of core–shell structures,rolling engineering,ferroelectric regulation,strain engineering,etc,with emphasis on the fundamental physical *** that,the ingenious optoelectronic applications based on the low-dimensional vdWM polarized photodetectors,including multiplexing optical communications and enhanced-contrast imaging,have been *** the end,the current challenges along with the future prospects of this burgeoning research field have been *** the whole,the review depicts a fascinating landscape for the next-generation high-integration multifunctional optoelectronic systems.

关键词： polarization-discriminating photodetectors 1D van der Waals materials

The Oblique Alfvén Ion Beam Instability in the Earth’s Ion Foreshock

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Research in Astronomy and Astrophysics 2023年第2期23卷 177-186页

作者： yuhang yao Jinsong Zhao Huasheng Xie Wen Liu Dejin Wu Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Hebei Key Laboratory of Compact Fusion Langfang 065001China ENN Science and Technology Development Co. Ltd.Langfang065001China

How ions evolve in the Earth’s ion foreshock is a basic problem in the heliosphere community,and the ion beam instability is usually proposed to be one major mechanism affecting the ion dynamics *** work will perform comprehensive analyses of the oblique ion beam instability in the Earth’s ion *** show that in addition to two well-known parallel instabilities (i.e.,the parallel fast-magnetosonic whistler instability and the parallel Alfvén ion cyclotron instability),the oblique Alfvén ion beam (OA/IB) instability can also be triggered by free energy relating to the relative drift d V between the solar wind proton and reflected proton *** slow d V (e.g.,d V■2.2V_(A),where VAdenotes the Alfvén speed),it only triggers the OA/IB *** d V■2.2V_(A),the growth rate in the OA/IB instability can be about 0.6 times the maximum growth rate in parallel ***,this work finds the existence of two types of OA/IB *** first one appears at slow d V and in the small wavenumber region at fast d V,and this instability can be described by the cold fluid *** second one arises in large wavenumber regions at fast d V,and this instability only appears in warm ***,through the energy transfer rate method,we propose that the OA/IB instability is driven by the competition among the Landau and cyclotron wave-particle interactions of beam protons,the cyclotron wave-particle interaction of core protons,and the Landau wave-particle interaction of *** oblique waves can experience significant damping,the importance of the OA/IB instability may be the effective heating of ions in the Earth’s foreshock.

关键词： plasmas-instabilities-waves-(Sun:)solar-terrestrial relations

Casein kinase-2 inhibition promotes retinal ganglion cell survival after acute intraocular pressure elevation

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Neural Regeneration Research 2024年第5期19卷 1112-1118页

作者： Meng Wang Shi-Qi yao yao Huang Jia-Jian Liang Yanxuan Xu Shaowan Chen yuhang Wang Tsz Kin Ng Wai Kit Chu Qi Cui Ling-Ping Cen Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong ShantouGuangdong ProvinceChina Shantou University Medical College ShantouGuangdong ProvinceChina Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijingChina Department of Ophthalmology and Visual Sciences The Chinese University of Hong KongHong Kong Special Administrative RegionChina

Intraocular pressure elevation can induce retinal ganglion cell death and is a clinically reversible risk factor for glaucoma,the leading cause of irreversible *** previously demonstrated that casein kinase-2 inhibition can promote retinal ganglion cell survival and axonal regeneration in rats after optic nerve *** investigate the underlying mechanism,in the current study we increased the intraocular pressure of adult rats to 75 mmHg for 2 hours and then administered a casein kinase-2 inhibitor(4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole)by intravitreal *** found that intravitreal injection of 4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole promoted retinal ganglion cell survival and reduced the number of infiltrating *** analysis showed that the mitogen activated protein kinase signaling pathway was involved in the response to intraocular pressure elevation but was not modulated by the casein kinase-2 ***,casein kinase-2 inhibition downregulated the expression of genes(Cck,Htrsa,Nef1,Htrlb,Prph,Chat,Slc18a3,Slc5a7,Scn1b,Crybb2,Tsga10ip,and Vstm21)involved in intraocular pressure *** data indicate that inhibition of casein kinase-2 can enhance retinal ganglion cell survival in rats after acute intraocular pressure elevation via macrophage inactivation.

关键词： casein kinase-2 glaucoma intraocular pressure elevation macrophages retinal ganglion cells

卟吩内酯化学:区域异构效应及其在稀土化学生物学中的应用

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中国稀土学报 2021年第3期39卷 456-468页

作者：姚宇航张俊龙北京大学化学与分子工程学院北京100871

卟啉的区域异构效应对其电子结构和生物功能产生重要影响,β位羰基取代的不饱和卟啉衍生物尤为明显。在卟吩内酯化合物中,通过引入二内酯结构和控制内酯基团的取向精准调控卟啉配体的三线态能级,实现了对Yb3+近红外发光、单线态氧敏化... 详细信息

卟啉的区域异构效应对其电子结构和生物功能产生重要影响,β位羰基取代的不饱和卟啉衍生物尤为明显。在卟吩内酯化合物中,通过引入二内酯结构和控制内酯基团的取向精准调控卟啉配体的三线态能级,实现了对Yb3+近红外发光、单线态氧敏化、光催化反应和三线态湮灭上转换等三线态能量传递过程的调控。通过芳香性的调控实现了对区域异构效应的放大,实现生物功能化的调控。并且在近期的工作中成功实现了诊(断)(治)疗一体化以及"多合一"光诊疗试剂,展现出极好的生物医学应用前景。本文综述了区域异构效应对卟啉配体的调控及其在稀土化学生物学中的研究进展,展望了其发展的方向和趋势以及在生物医学领域广阔的应用前景。

关键词：卟啉分子区域异构芳香性激发态调控稀土化学生物学

Surface Patterning of Metal Zinc Electrode with an In‑Region Zincophilic Interface for High‑Rate and Long‑Cycle‑Life Zinc Metal Anode

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Nano-Micro Letters 2024年第6期16卷 192-209页

作者： Tian Wang Qiao Xi Kai yao yuhang Liu Hao Fu Venkata Siva Kavarthapu Jun Kyu Lee Shaocong Tang Dina Fattakhova‑Rohlfing Wei Ai Jae Su Yu Department of Electronics and Information Convergence Engineering Institute for Wearable Convergence ElectronicsKyung Hee UniversityYongin‑siGyeonggi‑do 17104Republic of Korea Frontiers Science Center for Flexible Electronics(FSCFE)and Shaanxi Institute of Flexible Electronics(SIFE) Northwestern Polytechnical University(NPU)127 West Youyi RoadXi’an 710072People’s Republic of China Institute of Energy and Climate Research:Materials Synthesis and Processing(IEK‑1) Forschungszentrum Julich GmbH52425 JulichGermany School of Chemical Engineering Sungkyunkwan University2066 Seobu‑RoJangan‑GuSuwon‑siGyeonggi‑doRepublic of Korea

The undesirable dendrite growth induced by non-planar zinc(Zn)deposition and low Coulombic efficiency resulting from severe side reactions have been long-standing challenges for metallic Zn anodes and substantially impede the practical application of rechargeable aqueous Zn metal batteries(ZMBs).Herein,we present a strategy for achieving a high-rate and long-cycle-life Zn metal anode by patterning Zn foil surfaces and endowing a Zn-Indium(Zn-In)interface in the *** accumulation of electrons in the microchannel and the zincophilicity of the Zn-In interface promote preferential heteroepitaxial Zn deposition in the microchannel region and enhance the tolerance of the electrode at high current ***,electron aggregation accelerates the dissolution of non-(002)plane Zn atoms on the array surface,thereby directing the subsequent homoepitaxial Zn deposition on the array ***,the planar dendrite-free Zn deposition and long-term cycling stability are achieved(5,050 h at 10.0 mA cm^(−2) and 27,000 cycles at 20.0 mA cm^(−2)).Furthermore,a Zn/I_(2) full cell assembled by pairing with such an anode can maintain good stability for 3,500 cycles at 5.0 C,demonstrating the application potential of the as-prepared ZnIn anode for high-performance aqueous ZMBs.

关键词： Zn metal anode Surface patterning Directional Zn deposition Aqueous Zn-I_(2)batteries

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含自由金属微粒流动变压器油的直流击穿特性

电工技术学报 2023年第S1期38卷 157-167页

作者：姚雨杭陶霰韬于梦悦潘成唐炬电网环境保护全国重点实验室、武汉大学电气与自动化学院武汉430072 中国电力科学研究院有限公司武汉430074

自由金属微粒的污染是导致油浸式电力变压器绝缘性能下降的重要原因之一,其运动行为与分布规律会受到油流的影响,从而导致变压器油的击穿特性发生变化,目前流动状态下含金属微粒变压器油的击穿特性和机理均不明确。该文利用所构建的流... 详细信息

自由金属微粒的污染是导致油浸式电力变压器绝缘性能下降的重要原因之一,其运动行为与分布规律会受到油流的影响,从而导致变压器油的击穿特性发生变化,目前流动状态下含金属微粒变压器油的击穿特性和机理均不明确。该文利用所构建的流动变压器油击穿特性试验平台,分别开展了无预压和有预压两种方式下变压器油的击穿试验,并记录了击穿前微粒的分布规律以及击穿时刻的放电信号。观测结果表明:无预压时,击穿前油隙内仅存在少量游离的金属微粒,而有预压后微粒则会在油流静止和较低流速时于电极间汇聚,显著提高击穿前的微粒浓度;此外,含金属微粒变压器油的特征击穿电压将随着流速的增大先迅速上升随后逐渐趋于稳定。在流速小于0.25 m/s时,预压后的击穿电压将低于无预压时,随流速的增大而逐渐接近。通过击穿过程观测发现含微粒变压器油的击穿均是由单颗金属微粒引起的,其在靠近上电极时将引发局部放电从而导致击穿的发生。最后,结合油隙内微粒分布的变化情况讨论了油流速度对变压器油击穿特性的影响机制。

关键词：自由金属微粒流动变压器油击穿特性局部放电