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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 638-648页

作者： Xiaoting Du Lei Zou Maiying Zhong the College of Electrical engineering and Automation Shandong University of Science and TechnologyQingdao 266590China IEEE the College of Information Science and technology Donghua UniversityShanghai 201620 the engineering research center of Digitalized Textile and Fashion technology Ministry of EducationShanghai 201620China

The present study addresses the problem of fault estimation for a specific class of nonlinear time-varying complex networks,utilizing an unknown-input-observer approach within the framework of dynamic event-triggered mechanism(DETM).In order to optimize communication resource utilization,the DETM is employed to determine whether the current measurement data should be transmitted to the estimator or *** guarantee a satisfactory estimation performance for the fault signal,an unknown-input-observer-based estimator is constructed to decouple the estimation error dynamics from the influence of fault *** aim of this paper is to find the suitable estimator parameters under the effects of DETM such that both the state estimates and fault estimates are confined within two sets of closed ellipsoid *** techniques of recursive matrix inequality are applied to derive sufficient conditions for the existence of the desired estimator,ensuring that the specified performance requirements are met under certain ***,the estimator gains are derived by minimizing the ellipsoid domain in the sense of trace and a recursive estimator parameter design algorithm is then ***,a numerical example is conducted to demonstrate the effectiveness of the designed estimator.

关键词： Dynamic event-triggered mechanism(DETM) fault estimation nonlinear time-varying complex networks set-member-ship filtering unknown input observer

Quantitative measurement and application of droplets on physical surfaces based on LIF technology

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Transportation Safety and Environment 2024年第2期6卷 104-113页

作者： Fan Wu Shuaixiong Zhou Qingmin Cui Renze Xu Hengkui Li Chao Yu Key Labor atory of Traffic Safety on Track of Ministry of Education School of Traffic&Transportation EngineeringCentr al South Univ ersityChangsha 410075HunanChina Joint International research Laboratory of Key Technologies for Rail Traffic Safety School of Traffic&Transportation EngineeringCentral South UniversityChangsha 410075HunanChina School of software Henan University of EngineeringZhengzhou 451191HenanChina National&Local Joint engineering research center of Safety technology for Rail Vehicle School of Traffic&Transportation EngineeringCentral South UniversityChangsha 410075HunanChina

Contaminated surfaces play a significant role in the transmission of respiratory infectious *** address this issue,we pre-sented a novel quantitative detection method for droplets on physical surfaces,based on the laser-induced fluorescence *** proposed detection method was demonstrated in a realistic high-speed train compartment scenario by simulating the process of droplet release during passengers’breathing and *** experimental results showed that this method could offer high precision(10-1 mg/m^(2))for detecting minute substance concentrations,and its ease of operation makes it suitable for complex en-gineering *** results also revealed that under the combined effects of the indoor airflow and breathing airflow,the range of droplets released by breathing activity exceeded two rows in front of and behind the release ***,we observed that a large number of droplets settled on the seat surfaces on both sides of the same row as the releaser,with over 36%of these droplets concentrated on the backrest area of the *** the respiratory jet velocity increased,the location with the most sed-iment droplets(accounting for 8%of the total sedimentation)occurred on the seat directly in front of the releaser,and approximately 48% of the droplets were found on the back of this *** proposed method overcomes the shortcomings of existing experimental methods in quantitatively capturing the motion characteristics of droplets in complex flow fields.

关键词： quantitative measurement sediment droplets physical surfaces fluorescence measurement high-speed train compart-ment

Multi-functional photonic spin Hall effect sensor controlled by phase transition

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Chinese Physics B 2024年第7期33卷 336-342页

作者：程杰李瑞昭程骋张亚林刘胜利董鹏 School of Science Jiangsu Province Engineering Research Center of Low Dimensional Physics and New EnergyNanjing University of Posts and TelecommunicationsNanjing 210023China College of Electronic and Optical engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electrical engineering Research Center of Intelligent Sensor and Network Engineering Technology of Jiangsu ProvinceNanjing Vocational University of Industry TechnologyNanjing 210023China

Photonic spin Hall effect(PSHE), as a novel physical effect in light–matter interaction, provides an effective metrological method for characterizing the tiny variation in refractive index(RI). In this work, we propose a multi-functional PSHE sensor based on VO_(2), a material that can reveal the phase transition behavior. By applying thermal control, the mutual transformation into different phase states of VO_(2) can be realized, which contributes to the flexible switching between multiple RI sensing tasks. When VO_(2) is insulating, the ultrasensitive detection of glucose concentrations in human blood is achieved. When VO_(2) is in a mixed phase, the structure can be designed to distinguish between the normal cells and cancer cells through no-label and real-time monitoring. When VO_(2) is metallic, the proposed PSHE sensor can act as an RI indicator for gas analytes. Compared with other multi-functional sensing devices with the complex structures, our design consists of only one analyte and two VO_(2) layers, which is very simple and elegant. Therefore, the proposed VO_(2)-based PSHE sensor has outstanding advantages such as small size, high sensitivity, no-label, and real-time detection, providing a new approach for investigating tunable multi-functional sensors.

关键词： photonic spin Hall effect multi-functional sensors phase transition sensing performance

Promoted catalytic property of Cu/SSZ-13 by introducing a minority of Mn for NO removal from diesel engine exhaust

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Chinese Journal of Chemical engineering 2024年第7期71卷 172-182页

作者： Runnong Yang Wuyuan Liu Zhaoying Wang Ming Sun Guangying Fu Zihan Gao Wenjian Jiao Rui Li Lin Yu Guangdong Provincial Laboratory of Chemistry and Fine Chemical engineering Jieyang center Jieyang 515200China Guangdong engineering technology research center of Modern Fine Chemical engineering School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006China Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Testing and Certification Business Department China Automotive Technology and Research Center Company LimitedWuhan 430056China Guangdong Foran technology Company Limited Foshan 528000China

The Cu-exchanged SSZ-13 with the small-pore chabazite framework is considered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic property,a series of Mn ion-assisted Cu/SSZ-13 powder catalysts were prepared by co-exchange method and stepwise exchange *** is found that the NH_(3)-SCR activity,N_(2) selectivity,hydrothermal stability and sulfur resistance of Cu/SSZ-13 are promoted by introducing a minority of Mn(0.15%to 0.23%(mass))through co-exchange *** results reveal that the Cu,Mn co-exchange enables the higher amounts of Cu^(2+)active sites,the abundant medium strong and strong acid,the optimized ratio of Lewis acid to Brønsted acid etc.,which are required for a good NH_(3)-SCR catalytic property over broad temperature range and under harsh working ***,a monolithic catalyst was prepared by impregnating a cordierite ceramic support into the coating slurry containing the optimized CuMn/SSZ-13 *** diesel engine bench tests show that Cu,Mn co-exchange gives the monolith catalyst a better catalytic property than commercial *** work provides an important guidance for the rational design of secondary-ion-assisted zeolites applied in NH_(3)-SCR.

关键词： MnCu/SSZ-13 Co-exchange Zeolite Catalysis Selective catalytic reduction

Correlation between hydration properties and electrochemical performances on Ln cation size effect in layered perovskite for protonic ceramic fuel cells

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Journal of Energy Chemistry 2024年第1期88卷 1-9,I0001页

作者： Inhyeok Cho Jiwon Yun Boseok Seong Junseok Kim Sun Hee Choi Ho-Il Ji Sihyuk Choi Department of Mechanical engineering Kumoh National Institute of TechnologyGumi 39177GyeongbukRepublic of Korea Department of Aeronautics Mechanical and Electronic Convergence EngineeringKumoh National Institute of TechnologyGumi 39177GyeongbukRepublic of Korea center for Energy Materials research Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea center for Hydrogen and Fuel Cell research Clean Technology Research DivisionKorea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Department of Energy and Environmental engineering University of Science and TechnologySeoul 02792Republic of Korea Nanomaterials Science and engineering Korea University of Science and Technology(UST)KIST CampusSeoul 02792Republic of Korea

PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula for Pr BSCF is AA'B_(2)O_(5+δ), with Pr(A-site) and Ba/Sr(A'-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer;thus, the A site cations(lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects,whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(LnBSCF,Ln=Pr, Nd, and Gd) cathodes. At 500 ℃, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of Pr BSCF < Nd BSCF < Gd BSCF. To elucidate the close relationship between hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated.

关键词： Protonic ceramic fuel cell Cathode Triple ionic and electronic conductor Hydration property Proton uptake Gibbs free energy

Influence of calendering process on the structural mechanics and heat transfer characteristics of lithium-ion battery electrodes via DEM simulations

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Particuology 2024年第2期85卷 252-267页

作者： Junpeng Zhang Jingna Sun Huagui Huang Zhenge Yuan National engineering research center for Equipment and technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004China Xingtai Naknor technology Co. LtdXingtai054000China

Elucidating the intricate correlation between calendering,structure,and performance is crucial to comprehending the relationship between performance parameters and process steps of lithium-ion batteries(LIBs).Discrete element method(DEM)simulations were adopted in this work to calculate the interparticle force and stress tensor under incremental calendering process conditions,which revealed the effect of the anisotropy of complex contact force network on the anisotropy of heat transfer within porous *** thermal conductivity of electrode was predicted using porosity to characterize the process-structure-performance *** comprehensive influence of contact number and con-tact area between particles and current collector determines the magnitude of interfacial thermal resistance and interfacial heat transfer *** the first time,this work quantitatively analyzed the structural mechanics and heat transfer mechanism during calendering process of porous electrodes,and the results indicate a promising way to optimize and design battery electrode structures.

关键词： Li-ion battery electrode Structural mechanicsAnisotropy Thermal conductivity Discrete element method

Power Flow Analytical Solutions and Multi-dimensional Voltage Stability Boundaries Based on Multivariate Quotient-difference Method

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1168-1178页

作者： Chengxi Liu Qiupin Lai School of Electrical engineering and Automation Wuhan UniversityWuhan 430072China Hubei engineering and technology research center for AC/DC Intelligent Distribution Network Wuhan 430072China IEEE

This paper proposes a novel Multivariate Quotient-Difference(MQD)method to obtain the approximate analytical solution for AC power flow ***,in the online environment,the power flow solutions covering different operating conditions can be directly obtained by plugging values into multiple symbolic variables,such that the power injections and consumptions of selected buses or areas can be independently *** method first derives a power flow solution through a Multivariate Power Series(MPS).Next,the MQD method is applied to transform the obtained MPS to a Multivariate Pad´e Approximants(MPA)to expand the Radius of Convergence(ROC),so that the accuracy of the derived analytical solution can be significantly *** addition,the hypersurface of the voltage stability boundary can be identified by an analytical formula obtained from the coefficients of *** direct method for power flow solutions and voltage stability boundaries is fast for many online applications,since such analytical solutions can be derived offline and evaluated online by only plugging values into the symbolic variables according to the actual operating *** proposed method is validated in detail on New England 39-bus and IEEE 118-bus systems with independent load variations in multi-regions.

关键词： Analytical power flow solution multivariate power series multivariate Padéapproximants multivariate quotient-difference multi-dimensional voltage stability boundary

Characteristics of turbulent flow in 3-D pools in the presence of submerged rigid vegetation in channel bed

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Journal of Hydrodynamics 2024年第1期36卷 158-169页

作者： Kourosh Nosrati Hossein Afzalimehr Jueyi Sui Hamid Reza Reisifar Natural Disasters Prevention research center Faculty of Civil EngineeringIran University of Science and TechnologyTehranIran School of engineering University of Northern British ColumbiaPrince GeorgeCanada

In this study,the interaction between 3-D bedforms and submerged rigid vegetation has been *** laboratory experiments were conducted to study the distribution of flow velocity,Reynolds shear stress,turbulent kinetic energy,and skewness coefficients for a constant density of *** showed that the velocity profile in the pool section deviates from those in the upstream section of the *** has been found that the dip parameter varied between 0.6H and 0.9H depending on various factors including bed roughness,vegetation distribution,and pool entrance/exit ***,scattered vegetation in the pool and differences in slopes created non-uniform flow ***,in the wake region behind each vegetated element,flow velocity reduced significantly,and small-scale eddies are formed,causing increased *** decreasing the entrance slope and bed roughness,relatively uniform flow and weaker turbulence was resulted,but the random distribution of vegetated elements counteracted this balance and intensified *** the decrease in the pool entrance slope,the contribution of sweep event decreased and the contribution of ejection event increased.

关键词： Submerged rigid vegetation 3-D pool Reynolds shear stress skewness coefficients

Enhancement of liquid-liquid micromixing performance in curved capillary microreactor by generation of Dean vortices

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Chinese Journal of Chemical engineering 2024年第4期68卷 76-82页

作者： Shaoyun Wu Zhuang Ma Zichi Yang Suying Zhao Caijin Zhou Huidong Zheng Fujian engineering research center of Advanced Manufacturing technology for Fine Chemicals College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou362114China

Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of *** this work,the novel curved capillary reactor with different shapes was designed to generate Dean flow,which was used to enhance the liquid-liquid micromixing *** Villermaux-Dushman probe reaction was employed to characterize the micromixing performance in different curved capillary *** effects of experiment parameters such as liquid flow rate,inner diameter,tube length,and curve diameter on micromixing performance were systematically *** the optimal conditions,the minimum value of the segmentation factor XS was *** was worth noting that at the low Reynolds number(Re<30),the change of curved shape on the capillary microreactor can significantly improve the micromixing performance with XS reduced by 37.5%.Further,the correlations of segment index XS with dimensionless factor such as Reynolds number or Dean number were developed,which can be used to predict the liquid-liquid micromixing performance in capillary microreactors.

关键词： Microreactor Process intensification Micromixing performance Dean flow

Improving flangeability of multiphase steel by increasing microstructural homogeneity

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Journal of Iron and Steel research(International) 2024年第7期31卷 1736-1745页

作者： Xiao-yu Yang Yong-gang Yang Xing Fang Han-long Zhang Zhen-li Mi Beijing Advanced Innovation center for Materials Genome engineering Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China Shanghai Baosteel Group Corp.technology center Shanghai 201900China

Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstructural homogeneity was advanced by adjusting the hard martensite/austenite(M/A)*** strength-flangeability was measured via uniaxial tensile tests and hole expansion *** microstructures were characterized using a scanning electron microscope equipped with an electron backscatter diffraction detector and a transmission electron *** tests were supplementally used to quantitatively reveal the microstructural homogeneity of the *** show that the adjusted multiphase steel achieves an excellent ultimate tensile strength(~800 MPa)and flangeability(~135%hole expansion ratio).A promising homogeneous multiphase microstructure was obtained by controlling undercooled austenite transformed at about 600℃.This microstructure consists of soft polygonal ferrite,blocky bainitic ferrite,and hard M/A *** volume fraction of M/A islands is around 5%,and the average size is less than l *** nanoindentation analysis indicated that the participation of M/A islands impressively influenced the microstructural *** strain partition and better mechanical compatibility were present in the adjusted multiphase steel since the plasticity initiation started late,which resulted in a positive ***,avoiding M/A islands distributed in the chain along the rolling direction on the matrix hindered the possibility of voids coalescing into cracks and stabilized the flanging performance.

关键词： Multiphase steel Flangeability Martensite/austenite island-Microstructural homogeneity-Microstructure Compact strip production process