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Journal of Systems Science & Complexity 2024年第3期37卷 1023-1036页

作者： ZHANG Ziwei SHEN Hao su Lei School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan 243002China Anhui Province Key Laboratory of Special Heavy Load Robot and School of Electrical and Information Engineering Anhui University of TechnologyMa'anshan243002China

In this work,an H_(∞)/passive-based secure synchronization control problem is investigated for continuous-time semi-Markov neural networks subject to hybrid attacks,in which hybrid attacks are the combinations of denial-of-service attacks and deception attacks,and they are described by two groups of independent Bernoulli *** this foundation,via the Lyapunov stability theory and linear matrix inequality technology,the H_(∞)/passive-based performance criteria for semi-Markov jump neural networks are ***,an activation function division approach for neural networks is adopted to further reduce the conservatism of the ***,a simulation example is provided to verify the validity and feasibility of the proposed method.

关键词： Activation function division approach deception attacks denial-of-service attacks H_(∞)/passive synchronization semi-Markov jump neural networks

Dynamic characteristics of multi-span spinning beams with elastic constraints under an axial compressive force

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 295-310页

作者： Xiaodong GUO Zhu su Lifeng WANG State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A theoretical model for the multi-span spinning beams with elastic constraints under an axial compressive force is *** displacement and bending angle functions are represented through an improved Fourier series,which ensures the continuity of the derivative at the boundary and enhances the *** exact characteristic equations of the multi-span spinning beams with elastic constraints under an axial compressive force are derived by the Lagrange *** efficiency and accuracy of the present method are validated in comparison with the finite element method(FEM)and other *** effects of the boundary spring stiffness,the number of spans,the spinning velocity,and the axial compressive force on the dynamic characteristics of the multi-span spinning beams are *** results show that the present method can freely simulate any boundary constraints without modifying the solution *** elastic range of linear springs is larger than that of torsion springs,and it is not affected by the number of *** an increase in the axial compressive force,the attenuation rate of the natural frequency of a spinning beam with a large number of spans becomes larger,while the attenuation rate with an elastic boundary is lower than that under a classic simply supported boundary.

关键词： multi-span spinning beam elastic constraint improved Fourier series free vibration semi-analytical solution

基于过程数据及分析的在线学习路径研究:规律与规划

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开放教育研究 2020年第3期26卷 58-70页

作者：崔萌穆肃黄晓地华南师范大学现代远程教育研究所广东广州510631 查尔斯特大学计算机与数学学院新南威尔士州奥尔伯里2640澳大利亚

学习路径能直观地反映学习者真实的学习过程,对优化学习、提供学习帮助、调整教学策略等具有重要意义。本研究从中英文核心文献库选取近五年"基于数据的学习路径分析"中文文献324篇、英文文献255篇,定量和定性分析学习路径的概念界定和... 详细信息

学习路径能直观地反映学习者真实的学习过程,对优化学习、提供学习帮助、调整教学策略等具有重要意义。本研究从中英文核心文献库选取近五年"基于数据的学习路径分析"中文文献324篇、英文文献255篇,定量和定性分析学习路径的概念界定和核心研究内容,最后总结出研究的发展趋势和未来展望。本研究发现:1)学习路径为单维或多维学习信息单元的组织序列,学习路径节点信息可以分为学习内容和学习行为两大类;2)核心研究内容有学习路径规划和学习路径发现。学习路径规划是利用数据规划未来路径,包括基于知识特征、学习者特征和综合情境特征生成最优学习路径,重在智能适应;学习路径发现研究关注发现已有学习路径数据的规律,包括普遍学习路径发现和最优学习路径发现,突出群体智能;3)研究发展趋势有:学习路径由静态预设转变到动态生成,学习路径分析数据参数由单一维度转向多维度整合,实现学习路径的技术方法趋向人工和机器结合;4)未来展望主要有:多维信息特征映射的教育知识图谱重构,面向学习过程综合情境感知的个性化学习路径生成,基于学习行为且体现群体智能的学习路径发现,多维度数据支持的在线学习路径可视化。

关键词：在线学习学习过程学习路径研究现状

Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei

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Journal of Forestry Research 2024年第1期35卷 12-28页

作者： Shicheng su Nianqing Jin Xiaoli Wei College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China Institute for Forest Resources and Environment of Guizhou Guizhou UniversityGuiyang 550025People’s Republic of China

Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the *** this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei *** canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following *** improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light *** the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral *** photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light *** a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal *** a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of *** seedlings,and a reduction increased light absorption and use capacity and height:diameter *** growth advantage transformed from diameter to height,enabling seedlings to access more *** findings suggest that the regeneration of shade-tolerant species such as *** could be enhanced if a targeted approach to thinning based on stand type was adopted.

关键词： Thinning Understory light environment Phoebe bournei Photosynthetic performance Growth performance

Impact of wastewater treatment plant effluent discharge on the antibiotic resistome in downstream aquatic environments:a mini review

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 131-141页

作者： Zhiguo su Lyujun Chen Donghui Wen School of Environment Tsinghua UniversityBeijng 100084China 2 Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environmental Technology and EcologyYangtze Delta Region Institute of Tsinghua UniversityJiaxing 314050China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China

Antimicrobial resistance(AMR)has emerged as a significant challenge in human *** treatment plants(WWTPs),acting as a link between human activities and the environment,create ideal conditions for the selection and spread of antibiotic resistance genes(ARGs)and antibioticresistant bacteria(ARB).Unfortunately,current treatment processes are ineffective in removing ARGs,resulting in the release of large quantities of ARB and ARGs into the aquatic environment through WWTP ***,in turn,leads to their dispersion and potential transmission to human through water and the food *** safeguard human and environmental health,it is crucial to comprehend the mechanisms by which WWTP effluent discharge influences the distribution and diffusion of ARGs in downstream *** this study,we examine the latest researches on the antibiotic resistome in various waterbodies that have been exposed to WWTP effluent,highlighting the key influencing ***,recommendations for future research and management strategies to control the dissemination of ARGs from WWTPs to the environment are provided,with the aim to achieve the“One Health”objective.

关键词： Antibiotic resistance genes(ARGs) Wastewater treatment plants(WWTPs) Effluent-receiving waterbodies Environmental risk Influencing mechanism

Ultra-high-Q free-space coupling to microtoroid resonators

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Light(Science & Applications) 2024年第4期13卷 682-695页

作者： Sartanee suebka Euan McLeod Judith su Wyant College of Optical Sciences University of ArizonaTucsonAZUSA Department of Biomedical Engineering University of ArizonaTucsonAZUSA

Whispering gallery mode(WGM)microtoroid resonators are one of the most sensitive biochemical sensors in existence,capable of detecting single *** main barrier for translating these devices out of the laboratory is that light is evanescently coupled into these devices though a tapered optical *** hinders translation of these devices as the taper is fragile,suffers from mechanical vibration,and requires precise ***,we eliminate the need for an optical fiber by coupling light into and out from a toroid via free-space coupling and monitoring the scattered resonant light.A single long working distance objective lens combined with a digital micromirror device(DMD)was used for light injection,scattered light collection,and *** obtain Q-factors as high as 1:6´108 with this *** induced transparency(EIT)-like and Fano resonances were observed in a single cavity due to indirect coupling in free *** enables improved sensing *** large effective coupling area(~10μm in diameter for numerical aperture=0.14)removes the need for precise *** performance was verified by combining the system with the frequency locked whispering evanescent resonator(FLOWER)approach to perform temperature sensing experiments.A thermal nonlinear optical effect was examined by tracking the resonance through FLOWER while adjusting the input *** believe that this work will be a foundation for expanding the implementation of WGM microtoroid resonators to real-world applications.

关键词： coupling scattered precise

是消极惰怠还是繁忙无助?——远程培训的教师阻抗研究

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开放教育研究 2017年第5期23卷 74-83页

作者：穆肃周腾温慧群华南师范大学现代远程教育研究所广东广州510631

教师远程培训在提供精心设计的培训内容、跨时空的公平学习机会及优质资源的同时,也出现教师消极抵触、应付了事、反感逃避等现象,这些现象可以用教师对远程培训的阻抗来概括。为明确阻抗产生的原因,本研究从教师个体、职业状况和远程... 详细信息

教师远程培训在提供精心设计的培训内容、跨时空的公平学习机会及优质资源的同时,也出现教师消极抵触、应付了事、反感逃避等现象,这些现象可以用教师对远程培训的阻抗来概括。为明确阻抗产生的原因,本研究从教师个体、职业状况和远程培训三个维度,提出引发阻抗的潜在因素、构成模型及对应假设,并利用针对潜在因素设计的测量工具对562名参加远程培训的教师进行测试。研究发现:教师个体及职业状况会引发或消减教师对远程培训的阻抗,且各阻抗因素之间无显著共线性关系;远程培训方式本身对阻抗无显著影响,不存在引发阻抗的因素;教师惰性心理、意外时间、非教学时间、心理负担、不安全感对阻抗有正向影响,精神利益、行政支持等对阻抗有负向影响。因此,培训者应针对正负向影响的阻抗因素采用相应措施和方法,以消减教师对远程培训可能产生的阻抗。

关键词：教师阻抗远程培训产生因素

Recurrent malignant hyperthermia after scoliosis correction surgery

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World Journal of Emergency Medicine 2024年第1期15卷 70-72页

作者： Junfeng su Man Huang Department of General Intensive Care Unit the Second Affi liated Hospital of Zhejiang University School of MedicineHangzhou 310052China Key Laboratory of Early Warning and Intervention of multiple Organ Failure Ministry of Education of the People's Republic of ChinaHangzhou 310052China

Malignant hyperthermia(MH)is a genetic disorder of skeletal muscle cells that affects muscle cytoplasmic calcium homeostasis,with high mortality and low ***,it presents with non-specific signs of a hypermetabolic response,including high fever,tachycardia,and elevated end-tidal carbon dioxide(ETCO_(2)).The successful treatment lies in the timely recognition and early use of dantrolene.[1]As an inhibitor of Ca2+release through ryanodine receptor(RYR)channels,the skeletal muscle relaxant dantrolene has proven to be both a valuable experimental probe of intracellular Ca2+signaling and a lifesaving treatment for MH.[2]Dominant mutations in the skeletal muscle RYR1 gene are well-recognized causes of both malignant hyperthermia susceptibility(MHS)and central core disease(CCD).

关键词： hyperthermia malignant elevated

Mass-produced and uniformly luminescent photochromic fibers toward future interactive wearable displays

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Light(Science & Applications) 2024年第4期13卷 593-595页

作者： Yan Li Yikai su Department of Electronic Engineering Shanghai Jiao Tong University200240 ShanghaiChina

Enabling flexible fibers with light-emitting capabilities has the potential to revolutionize the design of smart wearable interactive devices.A recent publication in Light Science&Application,an interdisciplinary team of scientists led by ***-Qing Lu and *** Tao has realized a highly flexible,uniformly luminescent photochromic fiber based on a mass-produced thermal drawing *** overcomes the shortcomings of existing commercial lightdiffusing fibers,exhibiting outstanding one-dimensional linear illumination *** research team integrated controllable photochromic fibers into various wearable interaction interfaces,providing a novel approach and insights to enable human-computer interaction.

关键词： interaction fibers uniformly

光腔衰荡光谱技术用于OH浓度测量的误差分析

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红外与激光工程 2017年第2期46卷 20-25页

作者：涂晓波陈爽苏铁母金河杨富荣中国空气动力研究与发展中心设备设计与测试技术研究所四川绵阳621000

光腔衰荡光谱技术(Cavity Ring Down Spectroscopy,CRDS)是一种高灵敏度的吸收光谱测量技术,在燃烧场激光光谱诊断领域里是一种十分重要的燃烧产物定量测量手段。文中研究了光腔衰荡光谱技术用于燃烧产物定量测量的原理,搭建了脉冲型光... 详细信息

光腔衰荡光谱技术(Cavity Ring Down Spectroscopy,CRDS)是一种高灵敏度的吸收光谱测量技术,在燃烧场激光光谱诊断领域里是一种十分重要的燃烧产物定量测量手段。文中研究了光腔衰荡光谱技术用于燃烧产物定量测量的原理,搭建了脉冲型光腔衰荡光谱技术实验系统,选取OHA2Σ+-X2Π(0,0)电子跃迁带的P1(2)吸收线谱,在常压条件下对平面火焰的OH浓度进行了定量测量,并对激光器线宽及线型、激光器的频率稳定性、火焰温度、光腔参数等因素对测量误差的影响进行了分析讨论。误差分析给出了光腔衰荡光谱技术的几个关键注意事项,可为光腔衰荡光谱技术的应用提供指南。

关键词：光腔衰荡光谱技术误差分析 OH 浓度测量平面火焰