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Photonic integrated spiking neuron chip based on a self-pulsating DFB laser with a saturable absorber

Photonics Research 2023年第8期11卷 1382-1389页

作者： YUECHUN SHI SHUIYING XIANG XINGXING GUO YAHUI ZHANG HONGJI WANG DIANZHUANG ZHENG YUNA ZHANG YANAN HAN YONG ZHAO XIAOJUN ZHU XIANGFEI CHEN XUN LI YUE HAO Yongjiang Laboratory Ningbo 315202China State Key Laboratory of Integrated Service Networks State Key Discipline Laboratory of Wide Bandgap Semiconductor TechnologyXidian UniversityXi’an 710071China Key Laboratory of Intelligent Optical Sensing and Manipulation Ministry of EducationNational Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesInstitute of Optical Communication EngineeringNanjing UniversityNanjing 210023China School of Science Jiangnan UniversityWuxi 214122China School of Information Science and Technology Nantong UniversityNantong 226019China department of Electrical and Computer Engineering McMaster UniversityHamiltonOantario L8S 4K1Canada

We proposed and experimentally demonstrated a simple and novel photonic spiking neuron based on a distributed feedback(DFB)laser chip with an intracavity saturable absorber(SA).The DFB laser with an intracavity SA(DFBSA)contains a gain region and an SA *** gain region is designed and fabricated by the asymmetric equivalentπ-phase shift based on the reconstruction-equivalent-chirp *** properly injected current in the gain region and reversely biased voltage in the SA region,periodic self-pulsation was experimentally observed due to the Q-switching *** self-pulsation frequency increases with the increase of the bias current and is within the range of several *** the bias current is below the self-pulsation threshold,neuronlike spiking responses appear when external optical stimulus pulses are *** results show that the spike threshold,temporal integration,and refractory period can all be observed in the fabricated DFB-SA *** numerically verify the experimental findings,a time-dependent coupled-wave equation model was developed,which described the physics processes inside the gain and SA *** numerical results agree well with the experimental *** further experimentally demonstrated that the weighted sum output can readily be encoded into the self-pulsation frequency of the DFB-SA *** also benchmarked the handwritten digit classification task with a simple single-layer fully connected neural *** using the experimentally measured dependence of the self-pulsation frequency on the bias current in the gain region as an activation function,we can achieve a recognition accuracy of 92.2%,which bridges the gap between the continuous valued artificial neural networks and spike-based neuromorphic *** the best of our knowledge,this is the first experimental demonstration of a photonic integrated spiking neuron based on a DFB-SA,which shows great potential to realizing large-scale mult

关键词： technique laser saturable

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Monte Carlo simulations of the bulk effects of Mg on the cohesion of the Ni3Al-x at.% Mg grain boundary--An instance of the double species model

Monte Carlo simulations of the bulk effects of Mg on the coh...

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第十次全国核结构研讨会暨第六次全国核结构专题讨论会

作者：郑里平王廷太李斗星 Shanghai Institute of Applied Physics Chinese Academy of SciencesP.O.Box 800-204201800 ShanghaiChinaand International Centre for Material PhysicsChinese Academy of Sciences110016 ShenyangChina Basis department Zhong Yuan Institute of Technology450007 ZhengzhouChina Shenyang National Laboratory for Materials Sciences Institute of Metal ResearchChinese Academy of Science110016 ShenyangChina

The double species model has been employed to calculate dependence of the grainboundary cohesion on the Mg bulk concentration,for the Ni3Al-x at.%Mg(100%Ni/100%Ni)[001]/∑5(210)/36.87°symmetric tilt grain boundary,at the *** show thatwhen x(the Mg bulk concentration)increases from 0.1 to 0.5,the Mg enrichment increases,boththe Ni enrichment and the Al depletion maximizes at x=*** calculations also show the bestcohesion of the grain boundary at x=0.2.

关键词： Grain boundary concentrations Inducing and segregating species Bulk effects

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Effect of Symmetry Energy on Neutron-proton Bremsstrahlung from Intermediate Energy Heavy-ion Reactions

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近代物理研究所和兰州重离子加速器实验室年报：英文版 2007年第1期 28-28页

作者： Yong Gaochan Li Baoan Chen Liewen department of Physics Texas A ＆ M University-Commerce Commerce TX 75429 USA. Institute of Theoretieal Physics the Shanghai Jiaotong University Shanghai China.

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中国男性精神分裂症患者吸烟、精神病理学、认知功能和治疗相关不良反应的病例对照研究(英文)

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中国药物依赖性杂志 2009年第4期18卷 283-293页

作者：张向阳曹连元陈大春綦凌燕陈松王帆修梅红吴桂英陆林 Thomas R Kosten The Menninger department of Psychiatry and Behavioral Sciences Baylor College of Medicine 北京市昌平区回龙观医院北京100096 北京大学中国药物依赖性研究所北京100191

目的:美洲和欧洲的精神分裂症患者的吸烟率是社区人群对照的3至4倍,与阴性症状和锥体外系综合征的减少及认知功能的改善有关。本研究的目的是在中国精神分裂症患者中观察这些因素的临床关联性。方法:采用尼古丁依赖自评量表(Fagerstrom ... 详细信息

目的:美洲和欧洲的精神分裂症患者的吸烟率是社区人群对照的3至4倍,与阴性症状和锥体外系综合征的减少及认知功能的改善有关。本研究的目的是在中国精神分裂症患者中观察这些因素的临床关联性。方法:采用尼古丁依赖自评量表(Fagerstrom Test for Nicotine dependence,FTND)和重复性成套神经心理状态测验(Repeatable Battery for the Assessment of Neuropsychological Status,RBANS),我们对776例男性和560例男性社区对照进行了比较。患者也测评了阳性和阴性症状量表(Positive and Negative Symptom Scale,PANSS)、Simpson -Angus锥体外系副反应评定量表(Simpson and Angus Extrapyramidal Symptom Rating Scale,SAES)和不自主运动量表(Abnormal Involuntary Movement Scale,AIMS)。结果:精神分裂症患者终生吸烟率较社区对照人群高(79%比63%),同时严重吸烟者与对照组之间有更明显的差异(61%比31%)。现在吸烟者的PANSS阴性症状和SAES帕金森综合征得分均低于非吸烟者。吸烟的精神分裂症患者在RBANS认知功能测试中表现最差,非吸烟精神分裂症患者较差,之后是吸烟者,非吸烟者对照表现最好。结论:中国精神分裂症患者的吸烟率高于社区对照人群,但精神分裂症患者和对照组之间尼古丁依赖率与美洲观察到的情况有很大的差异。吸烟与较低水平的阴性症状,较少的锥体外系综合征及较少的帕金森综合征相关联,提示自我治疗的存在。但是,吸烟在精神分裂症患者和对照组人群中都与显著的认知功能损害相关联。

关键词：精神分裂症吸烟精神病理学认知不良反应尼古丁

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气候变化下多年冻土融水对青藏高原径流影响评估

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Science Bulletin 2023年第11期68卷 1105-1108,M0003页

作者：王泰华杨大文杨雨亭郑冠恒金会军李新姚檀栋程国栋 State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Institute of Cold Region Science and Engineering School of Civil EngineeringNortheast Forestry UniversityHarbin 150040China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China National Tibetan Plateau Data Center Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China Institute of Urban Study Shanghai Normal UniversityShanghai 200234China

青藏高原约40%的面积分布有多年冻土,相比冰川积雪融水得到的广泛关注,冻土融水对径流的影响仍有待评估.本研究基于耦合冰冻圈过程的分布式水文模型GBEHM(Geomorphology-based Ecohydrological Model),在区域尺度量化了多年冻土融水对... 详细信息

青藏高原约40%的面积分布有多年冻土,相比冰川积雪融水得到的广泛关注,冻土融水对径流的影响仍有待评估.本研究基于耦合冰冻圈过程的分布式水文模型GBEHM(Geomorphology-based Ecohydrological Model),在区域尺度量化了多年冻土融水对径流的影响.研究结果表明:(1)过去40年间,青藏高原多年冻土面积下降13.9%,地下冰储量减少约401.1 Gt,约为同期冰川储量减少量的2倍;(2)多年冻土融水对全青藏高原总径流贡献相对较小(约0.5%),但在某些区域(如黄河上游、长江上游)和高程范围(如河西走廊4000m高程附近),地下冰融水对径流的贡献超过冰川融水贡献,其影响不可忽略;(3)气候变化背景下,地下冰融水径流在未来不可持续,澜沧江、怒江等区域历史阶段已经达到峰值,而对全青藏高原,融水径流拐点预计将在21世纪20年代(SSP1-2.6)、50年代(SSP2-4.5)或90年代(SSP5-8.5)达到.

关键词：多年冻土地下冰分布式水文模型融水径流气候变化背景冰冻圈冰川融水青藏高原

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Ultimate Strength Assessment of Steel-Welded Hemispheres under External Hydrostatic Pressure

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Journal of Marine Science and Application 2020年第4期19卷 615-633页

作者： Sang-Rai Cho Teguh Muttaqie Seung Hyun Lee Jaewoo Paek Jung Min Sohn Ulsan Lab Inc.UlsanSouth Korea School of Naval Architecture and Ocean Engineering University of UlsanUlsanSouth Korea department of Naval Architecture and Marine Systems Engineering Pukyong National UniversityBusanSouth Korea Agency for the Assessment and Application of Technology Center of Technology for Defense and Security Industries-BPPTJakartaIndonesia Hyundai Mipo Dockyard UlsanSouth Korea Hyundai Heavy Industries UlsanSouth Korea Interdisciplinary Program of Marine Convergence Design Pukyong National UniversityBusanSouth Korea

This paper focusses on steel-welded hemispherical shells subjected to external hydrostatic *** experimental and numerical investigations were performed to study their failure *** model was fabricated from mild steel and made through press forming and *** therefore considered the effect of initial shape imperfection,variation of thickness and residual stress obtained from the actual *** hemisphere models designed with R/t from 50 to 130 were tested until *** to the test,the actual geometric imperfection and shell thickness were carefully *** comparisons of available design codes(PD 5500,ABS,DNV-GL)in calculating the collapse pressure were also highlighted against the available published test data on steel-welded ***,the nonlinear FE simulations were also conducted to substantiate the ultimate load capacity and plastic deformation of the models that were *** dependence of the level of sphericity,varying thickness and residual welding stresses were also numerically considered in the benchmark *** structure behaviour from the experiments was used to verify the numerical *** this work,both collapse pressure and failure mode in the numerical model were consistent with the experimental model.

关键词： Steel-welded hemisphere Collapse pressure Experiment Nonlinear FEA Ultimate strength formulation

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dependence of the Relationship between the Tropical Cyclone Track and Western Pacific Subtropical High Intensity on Initial Storm Size: A Numerical Investigation

Dependence of the Relationship between the Tropical Cyclone ...

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第33届中国气象学会年会

作者： Yuan Sun Zhong Zhong Lan Yi Tim Li Ming Chen Hongchao Wan Yuxing Wang Kai Zhong International Laboratory on Climate and Environment Change and Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology College of Meteorology and Oceanography PLA University of Science and Technology IPRC/AORC and department of Atmospheric Sciences University of Hawaii at Manoa Jiangsu Collaborative Innovation Center for Climate Change and School of Atmospheric Sciences Nanjing University National Climate Center and Chinese Academy of Meteorological Sciences National Center for Atmospheric Research

A suite of numerical experiments were conducted to investigate the sensitivity of the tropical cyclone（TC）motion-western Pacific subtropical high（WPSH）intensity relationship to initial storm *** TC cases,Songda（2004）and Megi（2010）,were *** was found that with the increase of initial storm size,the main body of the WPSH tends to withdraw eastward and the TC tends to turn northward *** involved physical mechanism was *** than the change of the beta effect due to storm size change,it is the change of the geopotential height in the TC outer region that is critical for the different TC tracks between the sensitivity *** to increase of the initial storm size,the inflow mass flux entering the TC region increases,leading to a significant decrease in 500-h Pa geopotential height in the TC outer region after 2-3-day *** a result,the simulated intensity of the WPSH over its fringe close to the TC decreases notably when the WPSH edge is within the TC outer *** a decrease leads to a break of ***,the TC turns northward towards the break of the subtropical *** further weakens the intensity of the WPSH over the region close to the *** result helps us better understand the relationship between the TC track and WPSH *** also indicates that a proper representation of initial storm size is important for realistic prediction of TC track and the change of the WPSH.

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Growth of NiFe Thin Fihns on Cu and Ta Seed Layers

Growth of NiFe Thin Fihns on Cu and Ta Seed Layers

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中国颗粒学会2006年年会暨海峡两岸颗粒技术研讨会

作者：胡淑芬 I Baginskiy 刘如熹黄昭渊 Taiwan Spin Research Center Chung Cheng University Chia-Yi 621China Nano Device Laboratories Hsinchu 300China Taiwan Spin Research Center Chung Cheng University Chia-Yi 621China Department of ChemistryTaiwan UniversityTaipei 106China Taiwan Spin Research Center Chung Cheng University Chia-Yi 621 China Taiwan Normal University Taipei 116 China

Ni80Fe20 permalloy can serve as an effective structural, as well as magnetic, seed layer for magnetic applications such as magnetoresistance random access memory (MRAM) technology and electrochemical deposition are generally more economical when compared to other deposition methods. In the present work NiFe thin films were obtained on sputtered Cu and Ta seed layers through electrodeposition from simple sulphate bath with and without organic additives. NiFe film surface topology and magnetic properties dependence on substrate material, bath composition and plating voltage have been investigated. The highest quality NiFe film was found to be obtained on Cu seed layer using low deposition voltages (0.9 V) while continuous film on Ta substrate is achievable only after 8-10 times longer deposition and has much higher roughness.

关键词： electrodeposition thin film NiFe

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农村土地承包经营权流转的调查分析——基于南昌市4县9村392户农户调研

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农林经济管理学报 2015年第3期14卷 289-295页

作者：蔡海生江西农业大学江西省鄱阳湖流域农业资源与生态重点实验室/南昌市鄱阳湖生态重点实验室/农村土地资源利用与保护研究中心江西南昌330045 department of Forest Resources Management/department of Earth and Environmental Sciences University of British ColumbiaVancouverB. C. Canada V6T 1Z4

通过对南昌市4县9村293户农户参与土地流转情况调研分析,南昌市农户农民进入快速分化期,土地流转进入快速发展期,土地流转管理服务进入规范建设期。但是,在土地流转适度规模经营模式、土地流转管理服务体系和市场机制、不同农户的发展... 详细信息

通过对南昌市4县9村293户农户参与土地流转情况调研分析,南昌市农户农民进入快速分化期,土地流转进入快速发展期,土地流转管理服务进入规范建设期。但是,在土地流转适度规模经营模式、土地流转管理服务体系和市场机制、不同农户的发展诉求和权益保障、土地流转监管执法等方面依然存在一些不足。其中原因在于:一是国家惠农政策提升了耕地的价值空间增强了农民对耕地的占有意识;二是"恋土"观念与"土地增值"思想的双重作用加深了农民的守土观点;三是农民收入水平及构成的变化弱化了土地的保障功能;四是受资金科技等因素制约适度规模经营难以全面扩大;五是农民发展与出路的随机性不确定性使得土地难以长期稳定流转。

关键词：农村土地流转发展现状问题与不足南昌市

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植根区域生长法(SRG)中的边界像素及其改进算法(英文)

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西南民族大学学报（自然科学版） 2003年第2期29卷 136-139页

作者：张明善黄健 Yudi Pawitanm 西南民族学院经济与管理学院爱尔兰国立Cork大学统计系 department of Medical Epidemiology Karolinska InstitutetP.O.Box 28117177StockholmSweden.

根植区域生长法(Seeded Region Growing)是处理图象分割的一种快捷的半自动算法([1],*** and ***,1994),也是目前处理图象问题的一种公认的有效方法和技术.边界像素对该算法的行为及效果有着微妙的但却是重要的.在应用中我们发现,当分... 详细信息

根植区域生长法(Seeded Region Growing)是处理图象分割的一种快捷的半自动算法([1],*** and ***,1994),也是目前处理图象问题的一种公认的有效方法和技术.边界像素对该算法的行为及效果有着微妙的但却是重要的.在应用中我们发现,当分割块处于狭窄连通状态时,这一算法常常是失败的,而失败的结果通常会导致原始图象的细节失真或者过分地依赖种子的选择.针对这一问题,我们对***和***的植根区域生长法进行了改进,给出了一个有效算法,解决了原来算法对狭窄连通分割块失败的问题.

关键词：植根区域生长法边界像素改进算法图象分割

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