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Chinese Physics B 2021年第6期30卷 62-76页

作者： bin he Qing Meng College of Mathematics and Statistics Honghe UniversityMengzi 661100China

The Schamel–Korteweg–de Vries equation is investigated by the approach of *** existences of solitary wave including ω-shape solitary wave and periodic wave are proved via investigating the dynamical behaviors with phase space *** sufficient conditions to guarantee the existences of the above solutions in different regions of the parametric space are *** possible exact explicit parametric representations of the waves are also *** with the details of the analyses,the analytical results are numerically simulated lastly.

关键词： Schamel–Korteweg–de Vries equation dynamical behavior solitary wave solution periodic wave solution

Orientation Field Code Hashing:A Novel Method for Fast Palmprint Identification

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IEEE/CAA Journal of Automatica Sinica 2021年第5期8卷 1038-1051页

作者： Xi Chen Ming Yu Feng yue bin Li the School of Electronic and Information Engineering Hebei University of Technology(HEBUT)Tianjin 300401 Beijing Institute of New Technology Applications Beijing Academy of Sciences and TechnologyBeijing 100035China the School of Articial Intelligence Hebei University of Technology(HEBUT)Beijing 100035China

For a large-scale palmprint identification system,it is necessary to speed up the identification process to reduce the response time and also to have a high rate of identification *** this paper,we propose a novel hashing-based technique called orientation field code hashing for fast palmprint *** investigating hashing-based algorithms,we first propose a double-orientation encoding method to eliminate the instability of orientation codes and make the orientation codes more ***,we propose a window-based feature measurement for rapid searching of the *** explore the influence of parameters related to hashing-based palmprint *** have carried out a number of experiments on the Hong Kong Poly U large-scale database and the CASIA palmprint database plus a synthetic *** results show that on the Hong Kong Poly U large-scale database,the proposed method is about 1.5 times faster than the state-of-the-art ones,while achieves the comparable identification *** the CASIA database plus the synthetic database,the proposed method also achieves a better performance on identification speed.

关键词： Biometric system hashing orientation feature palmprint identification

Approach to Phonon Relaxation Time and Mean Free Path in Nonlinear Lattices

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Chinese Physics Letters 2021年第4期38卷 56-60页

作者： yue Liu Dahai he Department of Physics Xiamen UniversityXiamen 361005China

Based on the self-consistent phonon theory,the spectral energy density is calculated by the canonical transformation and the Fourier *** fitting the spectral energy density by the Lorentzian profile,the phonon frequency as well as the phonon relaxation time is obtained in one-dimensional nonlinear lattices,which is validated in the Fermi-Pasta-Ulam-β(FPU-β) and φ^(4) lattices at different *** phonon mean free path is then evaluated in terms of the phonon relaxation time and phonon group *** results show that,in the FPU-β lattice,the phonon mean free path as well as the phonon relaxation time displays divergent power-law *** divergent exponent coincides well with that derived from the Peierls-Boltzmann theory at weak anharmonic *** value of the divergent exponent expects a power-law divergent heat conductivity with system size,which violates Fourier’s *** the φ^(4) lattice,both the phonon relaxation time and mean free path are finite,which ensures normal heat conduction.

关键词： phonon relaxation exponent

Effects of fabricated error on transmission performance of double layer frequency selective surface configuration

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光学精密工程 2005年第5期13卷 599-603页

作者： he bin SUN Lian-chun Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033China

Based on the experimental results, in which the fabricated error of the double layer frequency selective surface (FSS) leads to the transmission loss and the resonant frequency leaves away the design resonant frequency, the inter-layer separation distance (ISD) and the unit cell aligning error (UAE) were used as main variables to study the transmission performance attenuation of the double layer FSS configuration. The numerical analysis model for ISD and UAE was established and also was used to simulate the ring unit cell FSS transmission performance by the finite element and periodic moment methods. The double layer ring aperture FSS configuration designed was used as the numerical model. As a result of the numerical analysis, it is shown that both ISD and UAE produce insertion transmission loss (ITL) and insertion phase distortion (IPD) directly. Furthermore, ISD results in more loss of the amplitude of the transmitted signal for the FSS than UAE. It is significant for the designer of the multiplayer FSS to assign the fabricated error of the FSS dielectric layers. The UAE introduces the insertion phase variation badly.

关键词： FSS 平衡性 ISD 结构设计 UAE 光学机械

Structure of a Phase-Separating System in the Presence of Oscillatory Particles

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Communications in Theoretical Physics 2004年第5X期42卷 773-778页

作者： HUANGFu-bin ZHUyue-Jin LOUSen-yue physicsDepartment ShanghaiJiaoTongUniversityShanghai200030China physicsDepartment NingboUniversityNingbo315211China

We numerically simulate the processing of the phase separation of the polymer blend-particle system under fluctuating fields by new discretization's form. Due to the presence of oscillatory particles which have an affinity for one of the components, the ordering mechanism of phase separation will be changed. By changing the oscillatory frequency ω and amplitude γ, we can find the formation of the striped structures either parallel or perpendicular to the oscillatory direction and obtain a diagram describing the orientational ordering of the domain structures.

关键词：共混聚合物相位独立性薄膜材料动力学结构

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基于形态学的采摘系统视觉控制研究

农机化研究 2025年第3期47卷 197-201页

作者：刘悦国家农产品现代物流工程技术研究中心济南250103 山东省农产品贮运保鲜技术重点实验室济南250103

以进一步提升采摘机器人系统的作业效率为目标,选取形态学算法作为支撑机理与参考基点,针对采摘系统的视觉控制展开设计。考虑采摘系统的模块分工与功能组成,搭建形态学图像检测与处理模型,并进行系统的整体布局与软硬件模块匹配,形成... 详细信息

以进一步提升采摘机器人系统的作业效率为目标,选取形态学算法作为支撑机理与参考基点,针对采摘系统的视觉控制展开设计。考虑采摘系统的模块分工与功能组成,搭建形态学图像检测与处理模型,并进行系统的整体布局与软硬件模块匹配,形成以形态学运算处理规则为主的采摘机器人控制系统。采摘作业控制试验结果表明:基于形态学的采摘系统视觉控制设计方案正确可行,在形态学运算程序的精准执行下,图像特征区别效率与目标识别准确率均得到明显改善,视觉定位时间误差相对降低了3.19%,整体系统的综合效率可达92.30%,满足智能采摘的设计要求。系统各组件运行平稳,采摘回放动作柔性可靠,可为类似智能收获装置创新优化提供一定的参考。

关键词：采摘机器人形态学算法视觉控制图像特征区别效率智能采摘

Kinematic and mixing characteristics of vortex interaction induced by a vortex generator model:a numerical study

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Applied Mathematics and Mechanics(English Edition) 2021年第3期42卷 387-404页

作者： Ziang WANG bin YU bin ZHANG Miaosheng he Hong LIU School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

The underlying effect of vortex interaction characterized by the merging and non-merging on mixing enhancement is of fundamental significance to understand the flow dynamics of strut injectors in *** from a simplified configuration of a vortex generator,this study focuses on the influence of geometric parameters on vortex structures and fluid mixing through compressible Navier-Stokes(NS)*** adjusting the induction of outer vortices,the inner co-rotating vortex pair exhibits two modes of interaction(merging/separation regime)reflected by closer/farther vortex *** by the zero variation rate of the inner vortex spacing,the critical state of equilibrium is *** critical condition is well predicted by a theoretical model based on the Biot-Savart *** the introduction of mixedness and mixing time,the intrinsic impact of interaction modes on fluid mixing is *** with the vortex dynamics in the merging regime,the one in the separation regime is more effective for passive scalar mixing *** efficient material stretching characterized by the higher interface stretching factor and averaging finite-time Lyapunov exponent(FTLE),the mixing time is shortened by as much as 2.5 times in the separation *** implication of the present two interaction regimes in mixing enhancement physically reflected by the averaging FTLE has the potential to improve the combustion performance and shorten the combustor chamber.

关键词： vortex interaction mode fluid mixing Lagrangian coherent structure(LCS) stretching effect

Spiramide, a New Diterpene Amide from the Roots of Spiraea japonica var. acuta

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Chinese Chemical Letters 2000年第9期11卷 789-792页

作者： yue Mao SheN Hong Ping he Yong Sheng ZHANG bin Gui WANG Xiao Jiang HAO Laboratory of Phytochemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Department of Plant Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Chinese Medical College of Yunnan Province Kunming 650031

Chemical investigation on the neutral fraction of the ethanol extract from the roots of Spiraea japonica var. acuta has resulted in the isolation of one new diterpene amide, spiramide (1). Structure elucidation for 1 ... 详细信息

关键词： Spiraea japonica var. acuta spiramide

Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders:drug stability,targeting efficiency,and safety

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Neural Regeneration Research 2025年第7期20卷 1883-1899页

作者： Mingyu Zhang Chunyu Xiang Renrui Niu Xiaodong he Wenqi Luo Wanguo Liu Rui Gu Department of Orthopedic Surgery China-Japan Union Hospital of Jilin UniversityChangchunJilin ProvinceChina

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely ***,their inability to cross the blood–brain barrier hampers the clinical translation of these therapeutic *** are nanoparticles composed of lipid bilayers,which can effectively encapsulate drugs and improve drug delivery across the blood–brain barrier and into brain tissue through their targeting and ***,they can potentially treat traumatic and nontraumatic central nervous system *** this review,we outlined the common properties and preparation methods of liposomes,including thin-film hydration,reverse-phase evaporation,solvent injection techniques,detergent removal methods,and microfluidics ***,we comprehensively discussed the current applications of liposomes in central nervous system diseases,such as Alzheimer's disease,Parkinson's disease,Huntington's disease,amyotrophic lateral sclerosis,traumatic brain injury,spinal cord injury,and brain *** studies related to liposomes are still in the laboratory stage and have not yet entered clinical ***,their application as drug delivery systems in clinical practice faces challenges such as drug stability,targeting efficiency,and ***,we proposed development strategies related to liposomes to further promote their development in neurological disease research.

关键词： Alzheimer's disease amyotrophic lateral sclerosis brain tumors central nervous system Huntington's disease liposome drug delivery neurological disorders Parkinson's disease spinal cord injury traumatic brain injury

Tunable Emission and Energy Transfer of the Novel KY_(1-x)(MoO_(4))_(2-y)(WO_(4))y:xLn^(3+)(Ln^(3+)=Dy^(3+),Eu^(3+),and Tm^(3+))Single-phase White Luminescence Phosphor for White LEDs

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1278-1286页

作者： ZHU Hai he bin HUANG Weigang Department of Oncology The Third People's Hospital of ChengduAfiliated Hospital of Southwest Jiaotong University&The Second Affiliated Hospital of ChengduChongqing Medical UniversityChengdu 610031China Medical Research Center The Third People's Hospital of ChengduAfiliated Hospital of Southwest Jiaotong University&The Second Afiliated Hospital of ChengduChongqing Medical UniversityChengdu 610031China National Engineering Research Center for Biomaterials College of Biomedical MaterialsSichuan UniversityChengdu 610064China College of Materials Science and Engineering Sichuan UniversityChengd 610064China

The phosphors of KY_(1-x)(MoO_(4))_(2-y)(WO_(4))y:xLn^(3+)(Ln^(3+)=Tm^(3+),Dy^(3+),Eu^(3+))were synthesized by using a sol-gel ***,the crystal structure,luminescence properties,energy transfer,and white emission of the prepared materials were *** molar ratio of the anion group on the photoluminescence(PL)emission and excitation intensity were investigated,revealing that the optimum intensity could be obtained by using=3:*** optimal Dy^(3+) doping concentration of KY(MoO_(4))1.5(WO4)0.5was *** addition,the color-tunable emissions of Dy^(3+)/Eu^(3+)-codoped KY(MoO_(4))1.5(WO4)0.5phosphors were observed because of the effective energy transfer(ET)from Dy^(3+)to Eu^(3+)***,by doping appropriate concentrations of Tm^(3+),Dy^(3+),and Eu^(3+)and different concentrations of(WO_(4))^(2-),white light emitting phosphors KY_(0.92)(WO_(4))2:0.01Tm^(3+),0.06Dy^(3+),0.01Eu^(3+)with excellent color-rending properties were *** chromaticity coordinate was calculated as(x=0.3238,y=0.3173),closing to the artificial daylight(D65,x=0.313,y=0.329)illuminant,and which indicates the potential application of near ultraviolet White light-emitting diodes(WLEDs).

关键词： rare earth phosphors white LEDs energy transfer sol-gel method