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High Voltage 2024年第5期9卷 1159-1170页

作者： Shunguang Lei Hongchun Shu Zhimin Li Yinan Hu Xincui Tian Taiwen Liu School of electric engineering and Automation Harbin Institute of TechnologyHarbinHeilongjiangChina department of electric engineering Kunming University of Science and TechnologyKunmingYunnanChina

Line-commuted converter(LCC)-voltage source converter(VSC)hybrid high voltage direct current(HVDC)transmission system is an innovative technology,the existing LCC and VSC protection require setting,and it is difficult to be directly applied in the LCC-VSC hybrid HVDC,which is a serious problem in practical engineering.A novel linear regression density peak clustering(LRDPC)approach is introduced for transmission line *** employs Least Squares linear regression to compute the fault current slope,followed by density peak clustering for fault type *** proposed protection structure is straightforward and setting-less,eliminating the need for fault pole selection elements and classification *** on the Kun-Liu-Long LCC-VSC HVDC RTDS system demonstrates the method's effectiveness in identifying diverse faults under varying conditions,including fault types,locations,resistances,and signal-to-noise ***,it remains robust against fault impedance(600Ω)and noise interference(20 dB).

关键词： fault converter system

Isothermal oxidation behavior of scandium and yttrium co-doped B2-type iron-aluminum intermetallics at elevated temperature

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Rare Metals 2018年第8期37卷 690-698页

作者： Dong-Qing Li Li-Xian Zhou Kuan-Jun Zhu Jian Gu Shu-Hui Zheng department of Transmission and Transformation engineering Mechanics China Electric Power Research Institute

B2 FeA1 intermetallic compounds modified with reactive elements （REs） including Sc and Y were fabricated by vacuum arc-melting, and the isothermal oxidation behavior of the RE-doped alloys at 1373 K was investigated. Both Sc and Y single-doping significantly decrease the alumina film growth rate of the alloys. The alumina film growth rate of Sc＋ Y co-doped alloy even further reduces compared to that of the Sc and Y single-doped alloys. The synergistic effect produced by Sc＋ Y codoping on the growth behavior of alumina was discussed. It could be anticipated that the combined additions of Sc and Y which have matched chemical properties might decrease the alumina film growth rate more effectively and provide FeA1 alloys with enhanced oxidation resistance.

关键词： Ferritic aluminides Reactive elements Codoping Isothermal oxidation Segregation

A Two-Stage Nonlinear Shrinkage of the Sample Covariance Matrix for Robust Capon Beamforming

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Chinese Journal of Electronics 2019年第5期28卷 962-967页

作者： WANG Jie YANG Guangquan HU Yi ZHANG Chunliang School of Mechanical and electric engineering Guangzhou University department of electrical engineering Computer Science University of Wisconsin-Milwaukee

When the number of snapshots used to estimate the Sample covariance matrix(SCM) approaches infinity and the array steering vector is accurately known, the Standard Capon beamformer(SCB) can better suppress spatial noises than data-independent beamformers. On the contrary, the performance of the SCB may decrease. To solve this problem, we propose a two-stage shrinkage scheme for the SCM. Specifically,in the first stage, the SCM is enhanced by the General linear combination(GLC) method, which will be referred to as GLC-SCM; and in the second stage, the GLCSCM is further improved with the Exponential matrix(EM) method, which will be referred to as *** with the conventional methods, the proposed method can achieve higher signal-to-interference-noise ratio output and more accurate signal power estimate.

关键词： Exponential Sample covariance matrix Robust Capon beamforming

Thermal Property Measurements of a Large Prismatic Lithium-ion Battery for electric Vehicles

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Journal of Thermal Science 2021年第2期30卷 477-492页

作者： CHENG Ximing TANG Yu WANG Zhenpo National engineering Lab for electric Vehicles Department of Vehicular EngineeringBeijing Institute of TechnologyBeijing 100081China

Because of the high cost of measuring the specific heat capacity and the difficulty in measuring the thermal conductivity of prismatic lithium-ion batteries,two devices with a sandwiched core of the sample-electric heating film-sample were designed and developed to measure the thermal properties of the batteries based on Fourier's thermal *** to electrical circuit modeling,two equivalent thermal circuits were constructed to model the heat loss of the self-made devices,one thermal-resistance steady circuit for the purpose of measuring the thermal conductivity,the other thermal-resistance-capacitance dynamic circuit for the purpose of measuring the specific heat *** the analytic method and recursive least squares,the lumped model parameters of these two thermal circuits were extracted to estimate the heat loss and correct the measured values of the self-made *** to the standard values of the reference samples of the glass and steel plates,the measured values were corrected to improve the measurement accuracies beyond 95% through steady thermal-circuit *** to the measured value of the specific heat capacity of the battery sample at 50% state of charge using the calorimeter,the measured value using the self-made device was corrected in order to elevate the measurement accuracy by about 90% through dynamic thermal-circuit *** verified through the experiments,it was reliable,convenient,and low cost for the proposed methodology to measure the thermal properties of prismatic lithium-ion batteries.

关键词： lithium-ion battery specific heat capacity thermal conductivity equivalent thermal circuit measurement

Recursive calibration for a lithium iron phosphate battery for electric vehicles using extended Kalman filtering

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2011年第11期12卷 818-825页

作者： Xiao-song HU Feng-chun SUN Xi-ming CHENG National engineering Laboratory for electric Vehicles Department of Mechanical EngineeringBeijing Institute of Technology Beijing 100081 China

In this paper,an efficient model structure composed of a second-order resistance-capacitance network and a simply analytical open circuit voltage versus state of charge(SOC) map is applied to characterize the voltage behavior of a lithium iron phosphate battery for electric vehicles(EVs).As a result,the overpotentials of the battery can be depicted using a second-order circuit network and the model parameterization can be realized under any battery loading profile,without a special characterization *** order to ensure good robustness,extended Kalman filtering is adopted to recursively implement the calibration *** linearization involved in the calibration algorithm is realized through recurrent derivatives in a recursive *** results show that the recursively calibrated battery model can accurately delineate the battery voltage behavior under two different transient power operating conditions.A comparison with a first-order model indicates that the recursively calibrated second-order model has a comparable accuracy in a major part of the battery SOC range and a better performance when the SOC is relatively low.

关键词： Model calibration Lithium iron phosphate battery electric vehicle (EV) Extended Kalman filtering

Dynamics and geometry of developing planar jets based on the invariants of the velocity gradient tensor

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Journal of Hydrodynamics 2015年第6期27卷 894-906页

作者：吴楠楠 SAKAI Yasuhiko NAGATA Kouji ITO Yasumasa School of electric Power engineering China University of Mining and Technology department of Mechanical Science and engineering Nagoya University

Based on the direct numerical simulation （DNS）, the developing planar jets under different initial conditions, e.g., the con- ditions of the exit Reynolds number and the exit mean velocity profile, are investigated. We mainly focus on the characteristics of the invariants of the velocity gradient tensor, which provides insights into the evolution of the dynamics and the geometry of the planar jets along with the flow transition. The results show that the initial flow near the jet exit is strongly predominated by the dissipation over the enstrophy, the flow transition is accompanied by a severe rotation and straining of the flow elements, where the vortex structure evolves faster than the fluid element deformation, in the fully-developed state, the irrotational dissipation is dominant and the most probable geometry of the fluid elements should remain between the biaxial stretching and the axisymmetric stretching. In addition, with a small exit Re and a parabolic profile for the exit mean streamwise velocity, the decay of the mean flow field and the magnitude of the turbulent variables will be strengthened in the process of the flow transition, however, a large exit Re will promote the flow transition to the fully-developed state. The cross-impact between the exit Re and the exit mean velocity profile is also observed in the present study.

关键词： planar jet direct numerical simulation (DNS) velocity gradient tensor flow transition joint probability density function(joint pdf)

Exploring the role of N-acetyltransferases in diseases:a focus on N-acetyltransferase 9 in neurodegeneration

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Neural Regeneration Research 2025年第10期20卷 2862-2871页

作者： Prajakta Deshpande Anuradha Venkatakrishnan Chimata Amit Singh department of Biology University of DaytonDaytonOHUSA Premedical Program University of DaytonDaytonOHUSA Center for Tissue Regeneration and engineering at Dayton(TREND) University of DaytonDaytonOHUSA Integrative Science and engineering Center University of DaytonDaytonOHUSA Center for Genomic Advocacy(TCGA) Indiana State UniversityTerre HauteINUSA

Acetyltransferases,required to transfer an acetyl group on protein are highly conserved proteins that play a crucial role in development and *** acetylation is a common post-translational modification pivotal to basic cellular *** to 80%-90%of proteins are acetylated during translation,which is an irreversible process that affects protein structure,function,life,and *** this review,we have discussed the various N-acetyltransferases present in humans,their function,and how they might play a role in ***,we have focused on N-acetyltransferase 9 and its role in microtubule *** have shed light on how N-acetyltransferase 9 and acetylation of proteins can potentially play a role in neurodegenerative *** have specifically discussed the N-acetyltransferase 9-acetylation independent function and regulation of c-Jun N-terminal kinase signaling and microtubule stability during development and neurodegeneration.

关键词： acetyl-coenzyme A Alzheimer’s disease animal models cell death drosophila eye human disease c-Jun N-terminal kinase signaling N-Acetyltransferases N-acetyltransferase 9 neurodegeneration

Co-production of hydrogen, oxygen, and electricity via an integrated solar-driven system with decoupled water electrolyzer and Na-Zn ion battery

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Journal of Energy Chemistry 2025年第1期100卷 621-627页

作者： Fei Lv Longjie Liu Jiazhe Wu Pengfei Wang Lixia Pan Dengwei Jing Yubin Chen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

Combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen （H2） and ***,the design and development of such systems is still in its ***,an integrated hydrogen-oxygen （O2）-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate （NaNiHCF） and Zn2+/Zn as dual redox *** decoupled electrolyzer enables to produce H2and O2in different time and space with almost 100%Faradaic efficiency at 100 mA ***,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A *** connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables.

关键词： Hydrogen electricity Decoupled water electrolyzer Na-Zn ion battery Solar energy

Accommodation of Curtailed Wind Power by electric Boilers Equipped in Different Locations of Heat-supply Network for Power System with CHPs

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 930-939页

作者： Yunfeng Ma Yang Yu Zengqiang Mi School of electrical and Electronic engineering North China Electric Power UniversityBeijingChina department of electrical engineering North China Electric Power UniversityBaodingChina

electric boilers (EBs) provide an alternative method to deal with the accommodation of curtailed wind power. To pursue the minimum coal consumption in the system, a dispatching model integrating combined-heat-and-power (CHP) plants and EBs in different locations is developed, and the penalty of wind power curtailment and cost of EB employment are also incorporated in the model. The transmission loss and transportation lag of heat-supply network as well as the elasticity of heat load are considered in this paper. A kind of constrained programming with stochastic and fuzzy parameters is applied to deal with the uncertainties. A case in East Inner Mongolia in China demonstrates that the EBs are able to absorb curtailed wind power and supply the heat. The results indicate that the utility of EBs in the primary or secondary heat-supply network to accommodate curtailed wind power is mainly related to the efficiency of heat transmission and the elasticity of heat load.

关键词： Wind power combined-heat-and-power(CHP)unit electric boiler(EB) heat-supply network

Embedding and Maximal Regular Differential Operators in Sobolev-Lions Spaces

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1493-1508页

作者： Veli B.SHAKHMUROV Istanbul University Engineering Faculty Department of Electric-Electronics EngineeringAvcilar 34850 Istanbul Turkey

This study focuses on vector-valued anisotropic Sobolev-Lions spaces associated with Banach spaces E0, E. Several conditions are found that ensure the continuity and compactness of embedding operators that are optimal regular in these spaces in terms of interpolations of spaces E0 and E. In particular, the most regular class of interpolation spaces Eα between E0, E depending on α and the order of space are found and the boundedness of differential operators D^α from this space to Eα-valued Lp,γ spaces is proved. These results are applied to partial differential-operator equations with parameters to obtain conditions that guarantee the maximal Lp,γ regularity and R-positivity uniformly with respect to these parameters.

关键词： embedding operators Banach-valued function spaces differential operator equations (DOE) maximal regularity operator-valued Fourier multipliers interpolation of Banach spaces