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Approach from the laboratory to the field: New strategies in the control of mosquito-borne infectious diseases

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Science China Life Sciences 2025年第1期68卷 303-305页

作者： Ziqian Xu Lianpan dai jun Liu National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases (NITFID) National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences

Vector-borne viruses, transmitted among humans and animal hosts through bites of vectors such as mosquitoes and ticks,pose a great and ongoing threat to public health and biosafety(Yang et al., 2022).Among them, dengue virus-induced epidemics, have dramatically increased worldwide in recent decades. The report released by the World Health Organization(WHO) at the end of 2023 showed that dengue epidemic globally surged in2023, with the number of reported cases nearing a historical peak.

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山西关帝山森林上限附近植被的性质与空间格局

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山地学报 2003年第1期21卷 63-67页

作者：田军刘鸿雁田育红戴君虎北京大学环境学院生态学系北京100871

山西关帝山是中国暖温带落叶阔叶林区域第四高峰,对气候指标的推算表明,关帝山主峰孝文山接近气候意义的林线,对其森林上限附近植被空间格局和性质的分析有助于认识中国东部暖温带高山林线的形成机制。通过野外调查和植被数量分析,探讨... 详细信息

山西关帝山是中国暖温带落叶阔叶林区域第四高峰,对气候指标的推算表明,关帝山主峰孝文山接近气候意义的林线,对其森林上限附近植被空间格局和性质的分析有助于认识中国东部暖温带高山林线的形成机制。通过野外调查和植被数量分析,探讨了关帝山森林上限附近植物群落的类型、植物群落与环境的关系、植物种类多样性的梯度、植被的性质等理论问题,初步得出:(1)气候和地形条件共同决定关帝山森林上限附近的植被格局;(2)对植被性质的分析表明,关帝山山顶植被为亚高山灌丛和亚高山草甸,不具备高山带的性质,验证了根据气候数据进行的推断;(3)关帝山森林上限附近植物物种多样性随海拔增加而上升,不同于暖温带具有高山带的山地。

关键词：亚高山灌丛亚高山草甸山西关帝山气候指标植被空间格局

用四波混频系统通过单层和多层畸变介质传输图象

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物理学报 1986年第10期 1347-1356页

作者：林红张洪钧戴建华中国科学院物理研究所

本文讨论了一种用四波混频系统通过单层和多层薄畸变介质传输图象的方法,并给出了单层和两层畸变介质时的消畸变实验结果。理论分析与实验结果是一致的。这种方法为解决通过厚畸变介质传输图象的问题提供了可能的途径。

关键词：图象单层四波混频光频转换

热处理前后镍基高温合金激光熔覆层的组织和力学性能

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机械工程材料 2016年第11期40卷 22-26,30页

作者：张尧成黄希望杨莉陈洪洲戴军张宁常熟理工学院机械工程学院江苏省机电产品循环利用技术重点建设实验室常熟215500 江苏省大型工程装备检测与控制重点建设实验室徐州221008

在GH4169高温合金板表面制备了GH4169合金激光熔覆层,然后对其进行了完全热处理、980STA热处理和双时效热处理,对热处理前后熔覆层的显微组织和力学性能进行了研究。结果表明:热处理前,熔覆层的顶部为等轴晶,中部和底部为树枝晶和等轴... 详细信息

在GH4169高温合金板表面制备了GH4169合金激光熔覆层,然后对其进行了完全热处理、980STA热处理和双时效热处理,对热处理前后熔覆层的显微组织和力学性能进行了研究。结果表明:热处理前,熔覆层的顶部为等轴晶,中部和底部为树枝晶和等轴晶的混合形态;热处理后,熔覆层中粗大的树枝晶组织有不同程度的细化,熔覆层的显微硬度和抗拉强度显著提高;完全热处理后,熔覆层的断裂形式主要为韧性断裂,980STA热处理和双时效热处理后,断裂形式为韧性断裂和脆性断裂共存的混合型断裂。

关键词：热处理激光熔覆 GH4169高温合金显微组织力学性能

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双稳液晶电光调制器

物理学报 1981年第6期32卷 810-819页

作者：张洪钧戴建华杨君慧高存秀中国科学院物理研究所

本文介绍了一种新的液晶混合双稳光学装置(LCBOD),观察到了液晶BOD两种运用方式的光学双稳态,描述了液晶BOD在光学逻辑元件和超线性调制上的应用,还研究了液晶BOD的瞬态响应,观察到了“临界延迟”现象,测量了开关时间,实验结果与Garmir... 详细信息

本文介绍了一种新的液晶混合双稳光学装置(LCBOD),观察到了液晶BOD两种运用方式的光学双稳态,描述了液晶BOD在光学逻辑元件和超线性调制上的应用,还研究了液晶BOD的瞬态响应,观察到了“临界延迟”现象,测量了开关时间,实验结果与Garmire的理论相符。

关键词：液晶材料液晶盒光学双稳态运用方式瞬态行为张洪钧光电材料电光调制器输出光强双稳 BOD

Driver-automation shared steering control for highly automated vehicles

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Science China(Information Sciences) 2020年第9期63卷 67-82页

作者： jun LIU hongyan GUO Linhuan SONG Qikun dai hong CHEN State Key Laboratory of Automotive Simulation and Control Jilin University College of Communication Engineering Jilin University Intelligent Connected Vehicle Development Institute China Faw Corporation Limited Clean Energy Automotive Engineering Center Tongji University

A model predictive control(MPC)-based shared steering framework for intelligent vehicles is proposed in this paper. The road boundary and vehicle stability boundary are regarded as the safe envelope,and the tradeoff between the freedom of driver operation and safety assurance of intelligent vehicles is made within this safe envelope. Under this cooperative steering framework, the reliability of drivers is analyzed in dangerous situations and in the predictive time domain, and two improved schemes are proposed. Under the two improved schemes, the weight of the control objective can be adaptively changed according to the results of the threat assessment and predetermined strategy. At the same time, an evaluation index named control intervention rate and risk rate is proposed to evaluate the designed human-vehicle cooperation scheme. The simulation results show that the performance of the two improved schemes in ensuring the safety of intelligent vehicles has been improved.

关键词： shared steering control moving horizon optimization hazard evaluation intelligent vehicle safe envelope

Feature Layer Fusion of Linear Features and Empirical Mode Decomposition of Human EMG Signal

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Journal of Electronic Science and Technology 2022年第3期20卷 257-269页

作者： jun-Yao Wang Yue-hong dai Xia-Xi Si the School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu611731China the Aircraft Swarm Intelligent Sensing and Cooperative Control Key Laboratory of Sichuan Province University of Electronic Science and Technology of ChinaChengdu611731China

To explore the influence of the fusion of different features on recognition,this paper took the electromyography(EMG)signals of rectus femoris under different motions(walk,step,ramp,squat,and sitting)as samples,linear features(time-domain features(variance(VAR)and root mean square(RMS)),frequency-domain features(mean frequency(MF)and mean power frequency(MPF)),and nonlinear features(empirical mode decomposition(EMD))of the samples were *** feature fusion algorithms,the series splicing method and complex vector method,were designed,which were verified by a double hidden layer(BP)error back propagation neural *** show that with the increase of the types and complexity of feature fusions,the recognition rate of the EMG signal to actions is gradually *** the EMG signal is used in the series splicing method,the recognition rate of time-domain+frequency-domain+empirical mode decomposition(TD+FD+EMD)splicing is the highest,and the average recognition rate is 92.32%.And this rate is raised to 96.1%by using the complex vector method,and the variance of the BP system is also reduced.

关键词： Complex vector method electromyography(EMG)signal empirical mode decomposition feature layer fusion series splicing method

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光学双稳态和混沌运动中的临界现象

物理学报 1985年第10期 1233-1240页

作者：王鹏业张洪钧戴建华中国科学院物理研究所

本文以具有反馈时间延迟的非线性系统弛豫方程为出发点,讨论了双稳态临界点的临界现象。发现双稳区边沿的临界慢化与混沌运动中切分叉点附近阵发混沌时间间隔发散具有一致性,临界指数为1/2。在双稳区(尖顶突变模型)的尖顶处,与双稳区边... 详细信息

本文以具有反馈时间延迟的非线性系统弛豫方程为出发点,讨论了双稳态临界点的临界现象。发现双稳区边沿的临界慢化与混沌运动中切分叉点附近阵发混沌时间间隔发散具有一致性,临界指数为1/2。在双稳区(尖顶突变模型)的尖顶处,与双稳区边沿临界点不同,它与混沌运动中倍周期分叉点及劈分叉点的临界慢化具有一致性,临界指数为1。上述结果具有普适性。以液晶混合光学双稳系统为例,进行了计算机实验,其结果与分析相一致。

关键词：临界现象双稳光学双稳系统阵发混沌双稳态临界慢化弛豫方程混沌运动

Preparation, characterization and photocatalytic activity of N-doped TiO_2 nanocrystals

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 701-706页

作者： hong-tao Gao Jing Zhou Dong-mei dai Guang-jun Liu College of Chemistry and Molecular Engineering Qingdao University of Science ＆ Technology Qingdao 266042 China Department of Chemistry Jining University Jining 273155 China

N-doped TiO2 nanocrystals were prepared using titanium alkoxide as precipitant with different proportional materials. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV-vis diffuse reflectance spectra. It is confirmed experimentally that the photocatalytic activity of N-doped TiO2 is much higher than that of Degussa P25, when used for the degradation of crystal violet. The degradation kinetics follows an apparent first-order reaction, which is consistent with a generally observed Langmuir-Hinshelwood mechanism. The doping of TiO2 with nitrogen significantly increases the absorption in the region of visible light. The energy of the band gap of N-doped TiO2 is 2.92 eV. The better performance of N-doped TiO2 can be explained by the fact that it is also excited with longer-wavelength light.

关键词： pbotocatalyst degradation nitrogen doping TiO2 nanocrystals visible light crystal violet