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Nano Research 2024年第9期17卷 8250-8260页

作者： Yun Han Di Lan Mengjun Han Zihao Xia Jiaxiao Zou Zirui Jia college of Chemistry and Chemical {1. Qingdao UniversityQingdao 266071China School of Materials Science and engineering Hubei University of Automotive TechnologyShiyan 442002China

The rational design of composition nanostructures and morphologies of the carbon-based composites materials has a significant potential for tuning electromagnetic parameters and thereby improving their performance as electromagnetic wave(EMW)*** this work,the flower-like Cu/Co-NC/MoS_(2)(NC=N-doped carbon skeleton)composites were successfully prepared by employing CuCoZn-ZIF(ZIF=zeolitic imidazolate framework)as precursor with subsequent annealing and hydrothermal *** unique flower-like morphology and electromagnetic synergy strategy between components enable the as-obtained Cu/Co-NC/MoS_(2)composites to exhibit outstanding microwave absorption ***,the minimum reflection loss of Cu/Co-NC/MoS_(2)reaches-54.36 dB at 2.7 *** the thickness reduces to 2.2 mm,the maximum effective absorption bandwidth can be achieved as large as 6.72 *** research develops useful ideas for optimizing multicomponent microwave absorbing materials.

关键词： ternary metal-organic frameworks(MOFs) MoS_(2) flower-like morphology microwave absorption

Application of deep learning for informatics aided design of electrode materials in metal-ion batteries

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Green Energy & Environment 2024年第5期9卷 877-889页

作者： Bin Ma Lisheng Zhang Wentao Wang Hanqing Yu Xianbin Yang Siyan Chen Huizhi Wang Xinhua Liu School of Transportation Science and engineering Beihang UniversityBeijing102206China college of {1. engineering Jilin UniversityChangchun130022China Department of Mechanical engineering Imperial College LondonLondonSW72BXUK

To develop emerging electrode materials and improve the performances of batteries,the machine learning techniques can provide insights to discover,design and develop battery new materials in high-throughput *** this paper,two deep learning models are developed and trained with two feature groups extracted from the Materials Project datasets to predict the battery electrochemical performances including average voltage,speciﬁc capacity and speciﬁc *** deep learning models are trained with the multilayer perceptron as the *** Bayesian optimization and Monte Carlo methods are applied to improve the prediction accuracy of *** on 1. types of ion batteries,the correlation coefﬁcients are maintained above 0.9 compared to DFT calculation results and the mean absolute error of the prediction results for voltages of two models can reach 0.41.V and 0.20 V,*** electrochemical performance prediction times for the two trained models on thousands of batteries are only 72.9 ms and 75.7 ***,the two deep learning models are applied to approach the screening of emerging electrode materials for sodium-ion and potassium-ion *** work can contribute to a high-throughput computational method to accelerate the rational and fast materials discovery and design.

关键词： Cathode materials Material design Electrochemical performance prediction Deep learning Metal-ion batteries

Parametric Optimization of Wheel Spoke Structure for Drag Reduction of an Ahmed Body

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Computer Modeling in engineering & Sciences 2024年第4期139卷 955-975页

作者： Huihui Zhai Dongqi Jiao Haichao Zhou Institute of Electrical and Information engineering Zhenjiang CollegeZhenjiang212028China School of automotive and Traffic {1. Jiangsu UniversityZhenjiang212013China

The wheels have a considerable influence on the aerodynamic properties and can contribute up to 25%of the total drag on modern *** this study,the effect of the wheel spoke structure on the aerodynamic performance of the isolated wheel is ***,the 35°Ahmed body with an optimized spoke structure is used to analyze the flow behavior and the mechanism of drag *** Fluent software is employed for this investigation,with an inlet velocity of 40 m/*** accuracy of the numerical study is validated by comparing it with experimental results obtained from the classical Ahmed *** gain a clearer understanding of the effects of the wheel spoke parameters on the aerodynamics of both the wheel and Ahmedmodel,and five design variables are proposed:the fillet angleα,the inside arc radius R1.the outside radius R2,and the same length of the chord L1.and *** variables characterize the wheel spoke *** Optimal Latin Hypercube designmethod is utilized to conduct the experimental *** on the simulation results of various wheel spoke designs,the Kriging model and the adaptive simulated annealing algorithm is selected to optimize the design *** objective is to achieve the best combination for maximum drag *** is indicated that the optimized spoke structure resulted in amaximum drag reduction of 5.7%and 4.7%for the drag coefficient of the isolated wheel and Ahmed body,*** drag reduction is primarily attributed to changes in the flow state around the wheel,which suppressed separation ***,it influenced the boundary layer thickness around the car body and reduced the turbulent kinetic energy in the wake *** effects collectively contributed to the observed drag reduction.

关键词： Ahmed body wheel spoke design parameter optimization drag reduction numerical simulation

Thermal safety boundary of lithium-ion battery at different state of charge

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Journal of Energy Chemistry 2024年第4期91卷 59-72页

作者： Hang Wu Siqi Chen Yan Hong Chengshan Xu Yuejiu Zheng Changyong Jin Kaixin Chen Yafei He Xuning Feng Xuezhe Wei Haifeng Dai Clean Energy automotive {1. Center Tongji UniversityShanghai 201804China college of Mechanical {1. University of Shanghai for Science and TechnologyShanghai 200093China State Key Laboratory of automotive Safety and Energy Tsinghua UniversityBeijing 100084China

Thermal runaway(TR)is a critical issue hindering the large-scale application of lithium-ion batteries(LIBs).Understanding the thermal safety behavior of LIBs at the cell and module level under different state of charges(SOCs)has significant implications for reinforcing the thermal safety design of the lithium-ion battery *** study first investigates the thermal safety boundary(TSB)correspondence at the cells and modules level under the guidance of a newly proposed concept,safe electric quantity boundary(SEQB).A reasonable thermal runaway propagation(TRP)judgment indicator,peak heat transfer power(PHTP),is proposed to predict whether TRP ***,a validated 3D model is used to quantitatively clarify the TSB at different SOCs from the perspective of PHTP,TR trigger temperature,SOC,and the full cycle ***,three different TRP transfer modes are *** interconversion relationship of three different TRP modes is investigated from the perspective of *** paper explores the TSB of LIBs under different SOCs at both cell and module levels for the first time,which has great significance in guiding the thermal safety design of battery systems.

关键词： Lithium-ion battery Battery safety Thermal runaway State of charge Numerical analysis

Wearable multilead ECG sensing systems using on-skin stretchable and breathable dry adhesives

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Bio-Design and Manufacturing 2024年第2期7卷 167-180页

作者： Yingxi Xie Longsheng Lu Wentao Wang Huan Ma School of Mechanical and automotive {1. South China University of TechnologyGuangzhou 510641China college of {1. and Mechanical engineering Changsha University of Science and TechnologyChangsha 410114China Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangzhou 510080China

Electrocardiogram(ECG)monitoring is used to diagnose cardiovascular diseases,for which wearable electronics have attracted much attention due to their lightweight,comfort,and long-term *** study developed a wearablemultilead ECG sensing system with on-skin stretchable and conductive silver(Ag)-coated fiber/silicone(AgCF-S)dry *** and normal adhesion to pigskin(0.43 and 0.20 N/cm2,respectively)was optimized by the active control of fiber density and mixing ratio,resulting in close contact in the electrode–skin *** breathableAgCF-S dry electrodewas nonallergenic after continuous fit for 24 h and can be reused/cleaned(>1.0 times)without loss of *** AgCF encapsulated inside silicone elastomers was overlapped to construct a dynamic network under repeated stretching(1.%strain)and bending(90°)deformations,enabling small intrinsic impedance(0.3,0.1.Hz)and contact impedance variation(0.7 k)in high-frequency vibration(70 Hz).All hard/soft modules of the multilead ECG system were integrated into lightweight clothing and equipped with wireless transmission for signal *** synchronous acquisition of I–III,aVR,aVL,aVF,and V4 lead data,the multilead ECG sensing system was suitable for various scenarios,such as exercise,rest,and sleep,with extremely high signal-to-noise ratios.

关键词： Multilead electrocardiogram Dry electrodes Wearable electronics Wireless transmission

Nonlinear Characteristic Analysis of Gas-Interconnected Quasi-Zero Stiffness Pneumatic Suspension System:A Theoretical and Experimental Study

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Chinese Journal of Mechanical engineering 2024年第3期37卷 338-352页

作者： Xinwei Jiang Xing Xu Tianling Shi Vincent Akolbire Atindana automotive {1. Research Institute Jiangsu UniversityZhenjiang 212013China

Because of significantly changed load and complex and variable driving road conditions of commercial vehicles,pneumatic suspension with lower natural frequencies is widely used in commercial vehicle suspension *** ever,traditional pneumatic suspension system is hardly to respond the greatly changed load of commercial vehicles To address this issue,a new Gas-Interconnected Quasi-Zero Stiffness Pneumatic Suspension(GIQZSPS)is presented in this paper to improve the vibration isolation performance of commercial vehicle suspension systems under frequent load *** new structure adds negative stiffness air chambers on traditional pneumatic suspension to reduce the natural frequency of the *** can adapt to different loads and road conditions by adjusting the solenoid valves between the negative stiffness air ***,a nonlinear mechanical model including the dimensionless stiffness characteristic and interconnected pipeline model is derived for GIQZSPS *** the nonlinear mechanical model of GIQZSPS system,the force transmissibility rate is chosen as the evaluation index to analyze ***,a testing bench simulating 1.4 GIQZSPS system is designed,and the testing analysis of the model validation and isolating performance is carried *** results show that compared to traditional pneumatic suspension,the GIQZSPS designed in the article has a lower natural *** the system can achieve better vibration isolation performance under different load states by switching the solenoid valves between air chambers.

关键词： Pneumatic suspension Quasi-zero stiffness system Gas-interconnected system Nonlinear dynamic modeling

Enhancing source domain availability through data and feature transfer learning for building power load forecasting

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Building Simulation 2024年第4期17卷 625-638页

作者： Fanyue Qian Yingjun Ruan Huiming Lu Hua Meng Tingting Xu college of Mechanical and Energy {1. Tongji UniversityShanghai200092China United automotive Electronic Systems Co. LtdShanghai201206China

During the initial phases of operation following the construction or renovation of existing buildings,the availability of historical power usage data is limited,which leads to lower accuracy in load forecasting and hinders normal ***,by transferring load data from similar buildings,it is possible to enhance forecasting ***,indiscriminately expanding all source domain data to the target domain is highly likely to result in negative transfer *** study explores the feasibility of utilizing similar buildings(source domains)in transfer learning by implementing and comparing two distinct forms of multi-source transfer ***,this study focuses on the Higashita area in Kitakyushu City,Japan,as the research *** buildings that exhibit the highest similarity to the target buildings within this area were selected for ***,the two-stage TrAdaBoost.R^(2) algorithm is used for multi-source transfer learning,and its transfer effect is ***,the application effects of instance-based(IBMTL)and feature-based(FBMTL)multi-source transfer learning are compared,which explained the effect of the source domain data on the forecasting accuracy in different transfer *** results show that combining the two-stage TrAdaBoost.R^(2) algorithm with multi-source data can reduce the CV-RMSE by 7.23%compared to a single-source domain,and the accuracy improvement is *** the same time,multi-source transfer learning,which is based on instance,can better supplement the integrity of the target domain data and has a higher forecasting ***,IBMTL tends to retain effective data associations and FBMTL shows higher forecasting *** findings of this study,which include the verification of real-life algorithm application and source domain availability,can serve as a theoretical reference for implementing transfer learning in load forecasting.

关键词： building power load multi-source transfer learning two-stage TrAdaBoost.R2 source domain availability

Co-estimation of state-of-charge and state-of-temperature for large-format lithium-ion batteries based on a novel electrothermal model

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Green Energy and Intelligent Transportation 2024年第4期3卷 23-38页

作者： Chao Yu Jiangong Zhu Wenxue Liu Haifeng Dai Xuezhe Wei School of automotive Studies Tongji UniversityShanghai201804China Clean Energy automotive {1. Center Tongji UniversityShanghai201804China college of Mechanical and Vehicle {1. Chongqing UniversityChongqing400044China

The safe and efficient operation of the electric vehicle significantly depends on the accurate state-of-charge(SOC)and state-of-temperature(SOT)of Lithium-ion(Li-ion)*** the influence of cross-interference between the two states indicated above,this study establishs a co-estimation framework of battery SOC and *** framwork is based on an innovative electrothermal model and adaptive estimation *** first-order RC electric model and an innovative thermal model are components of the electrothermal ***,the thermal model includes two lumped-mass thermal submodels for two tabs and a two-dimensional(2-D)thermal resistance network(TRN)submodel for the main battery body,capable of capturing the detailed thermodynamics of large-format Li-ion ***,the proposed thermal model strikes an acceptable compromise between the estimation fidelity and computational complexity by representing the heat transfer processes by the thermal ***,the adaptive estimation algorithms are composed of an adaptive unscented Kalman filter(AUKF)and an adaptive Kalman filter(AKF),which adaptively update the state and noise *** the estimation results,the mean absolute errors(MAEs)of SOC and SOT estimation are controlled within 1.and 0.4°C at two temperatures,indicating that the co-estimation method yields superior prediction performance in a wide temperature range of 5–35°C.

关键词： Large-format Li-ion battery Electrothermal model SOT estimation SOC estimation Adaptive algorithm

Machine learning enabling prediction in mechanical performance of Ti6Al4V fabricated by large-scale laser powder bed fusion via a stacking model

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Frontiers of Mechanical engineering 2024年第4期19卷 29-43页

作者： Changjun HAN Fubao YAN Daolin YUAN Kai LI Yongqiang YANG Jiong ZHANG Di WANG School of Mechanical and automotive {1. South China University of TechnologyGuangzhou 510641China Department of Mechanical engineering College of EngineeringCity University of Hong KongHong Kong 999077China

Determining appropriate process parameters in large-scale laser powder bed fusion(LPBF)additive manufacturing pose formidable challenges that necessitate advanced approaches to minimize trial-and-error during *** work proposed a data-driven approach based on stacking ensemble learning to predict the mechanical properties of Ti6Al4V alloy fabricated by large-scale LPBF for the first *** method can adapt to the complexity of large-scale LPBF data distribution and exhibits a more generalized predictive capability compared to base ***,the stacking model utilized artificial neural network(ANN),gradient boosting regressor,kernel ridge regression,and elastic net as base models,with the Lasso model serving as the *** optimization and cross-validation were utilized for model optimization and training based on a limited data set,resulting in higher predictive accuracy compared to traditional artificial neural network *** statistical analysis of the ANN and stacking models indicates that the stacking model exhibits superior performance on the test set,with a coefficient of determination value of 0.944,mean absolute percentage error of 2.51.,and root mean squared error of 27.64,surpassing that of the ANN *** statistical metrics demonstrate superiority over those obtained from the ANN *** results confirm that by integrating the base models,the stacking model exhibits superior predictive stability compared to individual base models alone,thereby providing a reliable assessment approach for predicting the mechanical properties of metal parts fabricated by the LPBF process.

关键词： machine learning laser powder bed fusion ensemble learning stacking algorithm additive manufacturing

A Coordinate-Free Approach to the Design of Generalized Griffis-Duffy Platforms

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Chinese Journal of Mechanical engineering 2024年第3期37卷 95-103页

作者： Chengwei Shen Xu Pei Lubin Hang Jingjun Yu college of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityHangzhou 311300China School of Mechanical engineering and Automation Beihang UniversityBeijing 100191China School of Mechanical and automotive {1. Shanghai University of Engineering ScienceShanghai 201620China

Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes *** remaining permanently in a singularity are beneficial for linearto-rotary motion ***-Duffy(GD)platform is a mobile structure admitting a Bricard *** this paper,we present a coordinate-free approach to the design of generalized GD platforms,which consists in determining the shape and attachment of both the moving platform and the fixed *** generalized GD platform is treated as a combination of six coaxial single-loop mechanisms under the same *** to the inversion,hidden in the geometric structure of these single-loop mechanisms,the mapping from a line to a circle establishes the geometric transformation between the fixed base and the moving platform based on the center of inversion,and describes the shape and attachment of the generalized GD ***,the center of inversion not only identifies the location of rotation axis,but also affects the shape of the platform mechanism.A graphical construction of generalized GD platforms using inversion,proposed in the paper,provides geometrically feasible solutions of the manipulator design for the requirement of the location of rotation axis.

关键词： Generalized Griffis-Duffy platforms Self-motion Inversion Coordinate-free determination Manipulator design