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采用端口阻抗测试的车载充电机传导电磁干扰建模方法研究

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西安交通大学学报 2025年第1期59卷 172-182页

作者：李季风耿宇宇贾晋廖兴林路青洋重庆理工大学电气与电子工程学院重庆400054 重庆理工大学汽车零部件先进制造技术教育部重点实验室重庆400054

针对电动汽车车载充电机的设计过程中普遍存在的电磁干扰频率范围广、干扰源复杂的问题,提出了一种基于端口阻抗测试的等效电路建模和系统级协同仿真方法。首先,通过对车载充电机系统各部件进行阻抗测试和三维电磁仿真,建立了无源器件... 详细信息

针对电动汽车车载充电机的设计过程中普遍存在的电磁干扰频率范围广、干扰源复杂的问题,提出了一种基于端口阻抗测试的等效电路建模和系统级协同仿真方法。首先,通过对车载充电机系统各部件进行阻抗测试和三维电磁仿真,建立了无源器件、端口滤波器和高压屏蔽线缆模型,提取了系统印制电路板关键回路的高频寄生参数。其次,建立了有源器件的仿真电路模拟器等效模型,并通过双脉冲实验验证模型的精度;针对功率因数校正电路控制环节的仿真与建模难以同步实现的问题,采用协同建模的方法构建整个系统的等效电路模型。最后,将各部件模型组合在一起,建立了完整的车载充电机系统传导电磁干扰预测模型,并依据相关测试标准进行了系统传导电磁干扰仿真和实验。结果表明:在150 kHz~30 MHz频率范围内,预测结果与实际结果的误差小于9 dB,具有良好的一致性,表明该模型能够精确预测车载充电机系统高压交流端的传导干扰水平,可以有效指导充电机系统的电磁兼容正向设计。

关键词：车载充电机电磁干扰端口阻抗测试协同仿真

Extend ethylene aromatization single-event kinetic modeling with physical and chemical descriptor based on ZSM-5 catalyst

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Petroleum Science 2023年第6期20卷 3841-3853页

作者： jia-Rong Xie Fang jin School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan430205HubeiChina Key Laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of TechnologyWuhan430205HubeiChina Novel Reactor&Green Chemical Technology Key Laboratory Wuhan Institute of TechnologyWuhan430205HubeiChina

The ethylene aromatization is critical for the methanol to aromatics and light alkane dehydroaromatization *** single-event microkinetic(SEMK)model combining the linear free energy theory and solid acid distribution concept were established and extend for the ethylene aromatization process,which can reduce the kinetic parameters and simplify the reaction network by comparison with the SEMK model including subtype elemen.ary steps based on the type of carbenium *** introducing deactivation parametersφinto the model and applying the linear free energy model to the deactivation experimen.al data,the obtained deactivation parametersφindicate that the carbon deposition precursors have the greatest impact on reducing the reaction rate of single-molecular reactions and the smallest impact on the hydrogen transfer ***,according to the change of reaction enthalpy,effect of carbenium ion structure on methylation,ethylation,cyclization and endo-βscission was investigated by introducing linear free energy concept into the SEMK *** effect of different acid strengths on elemen.ary steps was investigated based on the acid strength distribution model,it was found that the methylation and oligomerization reactions,the ali-βscission reaction,endo-βscission reaction and the cyclization reaction were more sensitive to strong acidity *** physisorption and chemisorption heat are separated from the protonation heat in the linear free energy kinetic model and the acid strength distribution kinetic model,and the absolute values of the obtained physisorption and chemisorption heat increase with the carbon number of carbenium ***,the parameters of the acid strength distribution kinetic model were applied to propane dehydroaromatization on H-ZSM-5 and the ethane dehydroaromatization on Zn/ZSM-5 to confirm the independence of parameters in the SEMK model with the similar reaction network.

关键词： Kinetic model Ethylene aromatization Acid strength distribution Linear free energy theory

Assessing ecological vulnerability in western China based on Time-Integrated NDVI data

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Journal of Arid Land 2016年第4期8卷 533-545页

作者： jin.jia WANG Quan Joint Research Center of Drylands Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Faculty of Agriculture Shizuoka UniversityShizuoka 422-8529Japan

Arid and semi-arid areas are the most vulnerable regions to climate change. Clear understanding of the effects of climate change on ecosystems in arid and semi-arid regions and the ecosystem vulnerability is important for ecosystem managemen. under the background of climate change. In this study, we conducted a vulnerability assessmen. on various ecosystems from 1982 to 2013 in western China with large areas of arid and semi-arid lands based on the Time-Integrated Normalized Difference Vegetation Index （TINDVI） data and climate data. The results indicated that grasslands were the most vulnerable ecosystem to climate change in western China, especially for those in Tibetan Plateau. Croplands in oases were not vulnerable to climate change compared to rain-fed croplands in semi-arid regions （e.g. Gansu and Inner Mongolia）, which was attributed to the well-developed drip irrigation technology in oases. Desert and Gobi ecosystems were slightly vulnerable to climate change during the past several decades. The assessmen. results, as revealed in this study, can provide a reference for taking appropriate actions to protect the ecosystems in western China.

关键词： vulnerability sensitivity adaptability climate change Time-Integrated Normalized Difference VegetationIndex (TINDVI) western China

Resting Study of Tracer Experimen. on Catalytic Wet Oxidation Reactor under Micro-gravity and Earth Gravity Conditions

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Chemical Research in Chinese Universities 2005年第6期21卷 702-706页

作者： YANG Ji jia jin-ping School of Environmen.al Science and Engineering Shanghai Jiaotong University Shanghai 200240 P. R. China

The International Space Station（ISS） employs catalytic wet oxidation carried out in a Volatile Reactor Assembly （VRA） for water recycling. Previous earth gravity experimen.s show that the VRA is very effective at removing polar, low molecular weight organics. To compare the reactor performance under micro-gravity and Earth gravity conditions, a tracer study was performed on a space shuttle in 1999 by using 0.2% potassium carbonate as the chemical tracer. In this paper, the experimen.al data were analyzed and it is indicated that the reactor can be considered as a plug flow one under both micro-gravity and earth gravity experimen.al conditions. It has also been proved that dispersion is not important in the VRA reactor under the experimen.al conditions. Tracer retardation was observed in the experimen.s and it is most likely caused by catalyst adsorption. It is concluded that the following reasons may also have influence on the retardation of mean residence time ：（1） the liquid can be held by appurtenances, which will retard the mean residence time; （2） the pores can hold the tracer, which can also retard the mean residence time.

关键词： Tracer study Micro-gravity Dispersion model Tank in series model Catalytic wet oxidation

Supercritical CO2 Assisted Preparation of Open-cell Foams of Linear Low-density Polyethylene and Linear Low-density Polyethylene/Carbon Nanotube Composites

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Chinese Journal of Polymer Science 2016年第7期34卷 889-900页

作者： jia wang 张利 jin-biao bao Ningbo Key Laboratory of Specialty Polymers Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China

The open-cell structure foams of linear low-density polyethylene（LLDPE） and linear low-density polyethylene（LLDPE）/multi-wall carbon nanotubes（MWCNTs） composites are prepared by using supercritical carbon dioxide（sc-CO2）as a foaming agent. The effects of processing parameters（foaming temperature, saturation pressure, and depressurization rate） and the addition of MWCNTs on the evolution of cell opening are studied systematically. For LLDPE foaming, the foaming temperature and saturation pressure are two key factors for preparing open-cell foams. An increase in temperature and pressure promotes both the cell wall thinning and cell rupture, because a high temperature results in a decrease in the viscosity of the polymer, and a high pressure leads to a larger amount of cell nucleation. Moreover, for the given temperature and pressure, the high pressurization rate results in a high pressure gradient, favoring cell rupture. For LLDPE/MWCNTs foaming, the addition of MWCNTs not only promotes the cell heterogeneous nucleation, but also prevents the cell collapse during cell opening, which is critical to achieve the open-cell structures with small cell size and high cell density.

关键词： Linear low-density polyethylene MWCNTs Supercritical carbon dioxide Foam Open-cell morphologies

Majorana zero mode in the vortex of an artificial topological superconductor

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Science China(Physics,Mechanics & Astronomy) 2017年第5期60卷 49-59页

作者： Hao-Hua Sun jin-Feng jia Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education) Department of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Majorana fermion （MF）, an exotic particle that is identical to its own antiparticle, was recently found in solid matter as a quasiparticle excitation, the Majorana zero mode （MZM）, in the vortex of an artificial topological superconductor （TSC）. This artificial TSC, first proposed by Fu and Kane in 2008, is a heterostructure made of a topological insulator BiETe3 and an s-wave superconductor NbSe2. This paper will briefly review the experimen.al progresses based on the Bi2Te3/NbSe2 heterostructure. All evidences are self-consistent and reveal that the MZM exists in the center of vortex. Those experimen.al results are also supported by theory. This finding is a milestone in the research ofMajorana fermions in solid state physics and a starting point of MZM＇s application in topological quantum computation.

关键词： Majorana fermion Majorana zero mode topological superconductor heterostructure vortex

Constrained reinforcemen. learning with statewise projection: a control barrier function approach

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Science China(Information Sciences) 2024年第3期67卷 136-154页

作者： Xinze jin Kuo LI Qingshan jia Departmen. of Automation Tsinghua University

Safety is a critical issue for reinforcemen. learning(RL), as it may be risky for some actual applications if the learning process involves unsafe exploration. Instead of formulating constraints as expectationbased in constrained RL, considering statewise safety in constrained RL is more meaningful. This work aims to address the issue of safe projection in RL by introducing a control barrier function that inherently learns a safe policy through a set certificate. We seek to analyze some theoretical properties of safe projection in the learning process, including convergence and performance bound, and extend the discussion into ensembles and guided controllers. Moreover, we approach analytical solutions for deterministic and stochastic system dynamics. Experimen.al results in different tasks show that the proposed method achieves better effects in terms of both performance and safety.

关键词： reinforcemen. learning safe projection control barrier function

Hybrid optimization for charge planning problem in twin strands continuous casting production

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Journal of Iron and Steel Research International 2021年第5期28卷 520-529页

作者： jian Yi Shu-jin.jia Bin Du College of Information Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Institute of Intelligent Manufacturing Baosteel Central Research InstituteShanghai 201900China

Charge planning is one of batching problems for steelmaking and continuous casting production,and its optimization will be conducive to subsequent cast *** planning problem in the twin strands continuous casting production was studied,where casting width of the odd strand might be different from that of the even *** the different widths in the twin strands,the resulting counterweights and the constraints of steelmaking and continuous casting,a multiobjective optimization model was established to minimize the number of charges,the number of scale pairs,the surplus and the upgrading costs of steel ***,a hybrid optimization algorithm combined with heuristic and mutation-based estimation of distribution algorithm was proposed to solve the *** were conducted on several groups of test data collected from practical production orders of *** computational results demonstrate that the proposed algorithm can generate better solutions than the manual *** proposed model and algorithm proved to be effective and practical.

关键词： Steelmaking Continuous casting Production planning Charge Cast Estimation of distribution algorithm

The essential functions of mitochondrial dynamics in immune cells

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Cellular & Molecular Immunology 2020年第7期17卷 712-721页

作者： jia-Huan Xie Yi-Yuan Li jin jin MOE Laboratory of Biosystem Homeostasis and Protection and Life Sciences Institute Zhejiang UniversityHangzhou 310058China Key Laboratory for Developmen.al Genes and Human Disease Ministry of EducationInstitute of Life SciencesJiangsu Province High-Tech Key Laboratory for Biomedical ResearchSoutheast UniversityNanjing 210096China Sir Run Run Shaw Hospital College of Medicine Zhejiang UniversityHangzhou 310016China

Mitochondria are highly mobile organelles due to fission,fusion,transport,and mitophagy,and these processes are known as mitochondrial *** dynamics play an important role in energy production,cell division,cell differentiation,and cell *** the past decade,numerous studies have revealed the importance of mitochondrial metabolism in immunity,and mitochondrial dynamics are essential for immune responses mediated by various cell *** this review,we mainly discuss the role of mitochondrial dynamics in activation,differentiation,cytokine production,and the activity of related pathways in immune cells,particularly T cells,B cells,and other cells involved in the innate immune response.

关键词： Mitochondrial dynamics Metabolism T cell B cell Innate immune cell