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考虑制动能量转移的复杂电气化铁路牵引用光伏发电系统综合能量管理策略

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电工材料 2024年第2期 54-58页

作者：郭跃进丁璨游海川张鸿荣三峡大学电气与新能源学院湖北宜昌443000

本研究提出了一种新的光伏发电系统,以有效缓解外部电网的压力,并实现有效的再生制动能量回收。首先对系统的能量控制模式进行了详细的分析;其次设计了一种考虑到相互制动能量转移的综合能源管理策略;利用粒子群(PSO)算法和优化过的粒... 详细信息

本研究提出了一种新的光伏发电系统,以有效缓解外部电网的压力,并实现有效的再生制动能量回收。首先对系统的能量控制模式进行了详细的分析;其次设计了一种考虑到相互制动能量转移的综合能源管理策略;利用粒子群(PSO)算法和优化过的粒子群算法,对背靠背变流器补偿功率参考值进行了计算;最后,通过实验来验证这一策略的有效性,并且比较两种算法的仿真结果的收敛性。通过MATLAB/Simulink仿真系统,建立了一个基于背靠背变流器的光伏接入牵引供电系统模型,并且设计了一套有效的能量管理策略和编码算法,以及一系列典型工况下的能源利用、相间制动能量转移情况,以及与不用算法的效果进行比较。经过研究发现,采用提出的系统架构和综合能源管理策略,可以有效地利用光伏发电,最大限度地优化相间制动能量的使用,而且优化后的收敛性也更加出色。

关键词：牵引用光伏系统制动能量能量管理背靠背变流器粒子群算法

Highly selective synthesis for 4,4′-bisphenol F from phenol and formaldehyde catalyzed with [C_4mim][HSO_4] ionic liquid

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Chinese Journal of Chemical Engineering 2016年第9期24卷 1166-1170页

作者： Danfeng Wang Zhicheng He Zhimin Wu Ying tan Yongfei Li yuejin Liu College of Chemical Engineering Xiangtan University

The effects of N-methylimidazole cation [Cnmim] with different alkyl chain lengths, the types of cations and anions of ionic liquids and the reaction parameters on the catalytic activity and the selectivity for 4,4′-bisphenol F were investigated. The hydrogen bonding between the hydroxyl of phenol and the C2-position hydrogen of imidazole moiety in hydrophilic imidazole-based ionic liquid has important influence on the selectivity for 4,4′-bisphenol F, and under the conditions of the molar ratio of phenol/[C4mim][HSO4] 1:1, reaction temperature65 °C and the theoretical molar ratio of phenol/formaldehyde 2:1, the selectivity for 4,4′-bisphenol F reached69.1%. Compared with the high phenol/formaldehyde ratio reported in literatures, the low molar ratio of phenol/formaldehyde and the low reaction temperature can greatly reduce energy consumption, and has important significance for industrial application.

关键词： 4,4′-Bisphenol F Phenol Formaldehyde 1-Butyl-3-methylimidazolium hydrogen sulfate

印刷装饰纸透气度对浸渍胶膜纸饰面刨花板表面耐开裂性能的影响

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中国人造板 2024年第4期31卷 12-15页

作者：赵丽媛陈晓平付跃进李珠中国林业科学研究院木材工业研究所北京100091 北京东兴茂木制品有限公司北京101100

对比研究了不同透气度印刷装饰纸,经相同浸渍、压贴工艺制成饰面刨花板的表面耐龟裂性能和表面耐冷热循环性能。结果表明,印刷装饰纸透气度(单位s/100 mL)数值越低,透气性能越好,相同工艺条件制备浸渍胶膜纸时上胶越容易,透气度为16.37 ... 详细信息

对比研究了不同透气度印刷装饰纸,经相同浸渍、压贴工艺制成饰面刨花板的表面耐龟裂性能和表面耐冷热循环性能。结果表明,印刷装饰纸透气度(单位s/100 mL)数值越低,透气性能越好,相同工艺条件制备浸渍胶膜纸时上胶越容易,透气度为16.37 s/100 mL的样品比透气度为65.02 s/100 mL的浸胶量提高了8.4%。当印刷装饰纸透气度大于35 s/100 mL时,由其浸胶后饰面制得的饰面刨花板表面耐龟裂性能和耐冷热循环性能不合格率分别为87.5%和75.0%。

关键词：透气度印刷装饰纸装饰胶膜纸饰面刨花板表面开裂

Transient evolution of quasifree electrons of plasma in liquid water revealed by optical-pump terahertz-probe spectroscopy

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Advanced Photonics 2021年第1期3卷 56-62页

作者： Yong tan Hang Zhao Rui Zhang yuejin Zhao Cunlin Zhang Xi-Cheng Zhang Liangliang Zhang Beijing Institute of Technology School of Optics and Photonics Beijing Key Laboratory for Precision Optoelectronic Measurement Instruments and Technology Chinese Academy of Sciences Shenzhen Institutes of Advanced Technology Capital Normal University Beijing Advanced Innovation Center for Imaging Technology and Key Laboratory of Terahertz Optoelectronics (MoE)Department of Physics University of Rochester Institute of Optics

The fundamental properties of laser-induced plasma in liquid water, such as the ultrafast electron migration and solvation, have not yet been clarified. We use 1650-nm femtosecond laser pulses to induce the plasma in a stable free-flowing water film under the strong field ionization mechanism. Moreover, we adopt intense terahertz(THz) pulses to probe the ultrafast temporal evolution of quasifree electrons of the laserinduced plasma in water on the subpicosecond scale. For the first time, the THz wave absorption signal with a unique two-step decay characteristic in time domain is demonstrated, indicating the significance of electron solvation in water. We employ the Drude model combined with the multilevel intermediate model and particlein-a-box model to simulate and analyze the key information of quasifree electrons, such as the frequencydomain absorption characteristics and solvation ratio. In particular, we observe that the solvation capacity of liquid water decreases with the increase of pumping energy. Up to ～50% of quasifree electrons cannot be captured by traps associated with the bound states as the pumping energy increases to 90 μJ∕pulse. The ultrafast electron evolution in liquid water revealed by the optical-pump/THz-probe experiment provides further insights into the formation and evolution mechanisms of liquid plasma.

关键词： terahertz liquid water plasma solvation

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基于百度贴吧的HIV高危人群特征分析

大数据 2019年第1期5卷 98-108页

作者：肖时耀吕慰陈洒然秦烁黄格蔡梦思谭跃进谭旭吕欣国防科技大学系统工程学院湖南长沙410073 湖南益阳康雅医院肿瘤科湖南益阳413002 深圳信息职业技术学院软件工程学院广东深圳518172

对百度贴吧"恐艾吧"中在线高危人群的帖子内容、线上活动时间规律进行了分析,利用LDA话题模型,对比分析了有无HIV感染者参与的主贴讨论的话题之间的差异,使用基于关键词的机器学习方法区分了在"恐艾吧"中发布话题的用户的性取向,计算不... 详细信息

对百度贴吧"恐艾吧"中在线高危人群的帖子内容、线上活动时间规律进行了分析,利用LDA话题模型,对比分析了有无HIV感染者参与的主贴讨论的话题之间的差异,使用基于关键词的机器学习方法区分了在"恐艾吧"中发布话题的用户的性取向,计算不同性取向人群中HIV的流行率。研究结果说明,使用在线数据挖掘的技术和方法比传统方法更加高效,可以作为高危人群研究的重要补充。此外,基于机器学习对人群性取向进行智能判别,对于公共卫生管理部门监测疫情在不同人群中的发展状况有重要意义。

关键词：在线高危人群男同性恋 HIV LDA话题模型百度贴吧机器学习

Analytical analysis of hollow CORC cable under thermo-mechanical loads

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Superconductivity 2023年第1期5卷 26-39页

作者： Xianhao Li yuejin tang Ying Xu Li Ren State Key Laboratory of Advanced Electromagnetic Engineering and Technology Wuhan 430074China School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074China

According to engineering experience,the axial shrinkage caused by the refrigerant seriously endangers the performance of long‐distance conductor on round core(CORC)*** outage maintenance of high‐temperature superconducting(HTS)cables is inevitable,providing appropriate compensation for cyclic temperature is one of the key technologies in the actual application of power ***,this paper presents an analytical solution for hollow CORC cables under thermo‐mechanical ***,regarded as an axisymmetric composite structure,the radial temperature distribution of CORC cable under Dirichlet boundary or mixed boundary conditions was ***,assuming cable ends were axially fixed,a recursive method without variables is used to evaluate its displacement,strains,and ***,an algebraic method with axial strain as a variable is developed to analyze the mechanical behavior of the CORC cable more ***,concluded from the above derivation,a matrix equation is constructed based on continuity equations and boundary conditions,which applies to isotropic and orthotropic materials with *** results show that the analytical solution agrees with finite element method(FEM)*** to the trial results of a 360 m CORC cable,the calculation error of axial shrinkage is within 1.63 cm,and the relative error is within 6.1%.In addition,the recursive method is the fastest to calculate axial strain,while the matrix method has a significant efficiency advantage in calculating the stresses and strains of each layer.

关键词： CORC cable Analytical solution Thermo‐mechanical loads Axial shrinkage Recursive method Algebraic method

Ultrafast hydrogen bond dynamics of liquid water revealed by terahertz-induced transient birefringence

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Light(Science & Applications) 2020年第1期9卷 707-716页

作者： Hang Zhao Yong tan Liangliang Zhang Rui Zhang Mostafa Shalaby Cunlin Zhang yuejin Zhao Xi-Cheng Zhang Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Beijing Advanced Innovation Center for Imaging Technology and Key Laboratory of Terahertz Optoelectronics(MoE) Department of PhysicsCapital Normal UniversityBeijing 100048China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China The Institute of Optics University of RochesterRochesterNY 14627USA

The fundamental properties of water molecules,such as their molecular polarizability,have not yet been *** hydrogen bond network is generally considered to play an important role in the thermodynamic properties of *** terahertz(THz)Kerr effect technique,as a novel tool,is expected to be useful in exploring the low-frequency molecular dynamics of liquid ***,we use an intense and ultrabroadband THz pulse(peak electric field strength of 14.9 MV/cm,centre frequency of 3.9 THz,and bandwidth of 1–10 THz)to resonantly excite intermolecular modes of liquid *** THz field-induced transient birefringence signals are observed in a free-flowing water *** propose a hydrogen bond harmonic oscillator model associated with the dielectric susceptibility and combine it with the Lorentz dynamic equation to investigate the intermolecular structure and dynamics of liquid *** mainly decompose the bipolar signals into a positive signal caused by hydrogen bond stretching vibration and a negative signal caused by hydrogen bond bending vibration,indicating that the polarizability perturbation of water presents competing contributions under bending and stretching conditions.A Kerr coefficient equation related to the intermolecular modes of water is *** ultrafast intermolecular hydrogen bond dynamics of water revealed by an ultrabroadband THz pump pulse can provide further insights into the transient structure of liquid water corresponding to the pertinent modes.

关键词： transient dynamics liquid

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经济系统中的非线性建模与仿真

计算机工程与应用 2001年第18期37卷 7-9页

作者：邓宏钟迟妍谭跃进国防科技大学系统工程研究所长沙410073

文章分析了经济学中传统非线性建模方法的不足，提出利用基于多智能体的整体建模仿真方法来建立经济系统的非线性仿真模型，作者利用swarm仿真软件平台生成了一个产品供求关系的非线性仿真模型，研究了供求平衡出现的条件和系统中的非... 详细信息

文章分析了经济学中传统非线性建模方法的不足，提出利用基于多智能体的整体建模仿真方法来建立经济系统的非线性仿真模型，作者利用swarm仿真软件平台生成了一个产品供求关系的非线性仿真模型，研究了供求平衡出现的条件和系统中的非线性现象，证明了这种方法的可行性和优越性。

关键词：经济系统非线性建模仿真经济学多智能体

Computational study of planar shock wave interacting with elliptical heavy gas bubble

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Acta Mechanica Sinica 2021年第8期37卷 1264-1277,I0002页

作者： Zhiwei Yang yuejin Zhu School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013China China Aerodynamics Research and Development Center Mianyang 621000China

High-precision numerical methods are utilized to study the shock waves interacting with an elliptical heavy *** influence of different bubble gases(SF6 and R22)and shock intensities(Ma=1.21 and Ma=2.1)is analyzed qualitatively and *** results show that the focusing position is farther from the right bubble interface in the SF6 bubble(case 1)than in the R22 bubble(case 2)when Ma=1.21;thus,case 2 exhibits an outward jet structure,while case 1 does *** Ma=2.1(case 3),the shock wave propagates faster,and the shock focusing is nearer to the right bubble ***,outward jet structures form on the bubble *** maximum values of density and pressure of shock focusing are different in the three cases,which imply that different gas densities and shock intensities significantly affect the shock-bubble *** effective bubble volume and gases mixing degree are both smaller in case 2 than in case 1,but the trends over time are essentially the *** increased shock intensity in case 3 leads to a smaller effective bubble volume than in case 1,but a much greater gases mixing *** all three cases,the compression term plays a more important role in the vorticity development than the other terms.

关键词： Shock wave Elliptical bubble Shock focusing Jet Vorticity