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Online preparation of high-quality BN coatings with atomic diffusion based on carbon-free water-soluble precursor

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Journal of Advanced Ceramics 2024年第3期13卷 272-281页

作者： Yiang Du Bing Wang Yunbo Zhang Quzhi Song Fuwen Wang Cheng Han Xiaoshan Zhang Yingde Wang Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Efficient and environmentally friendly production of high-quality continuous fiber coatings using current preparation methods is highly challenging due to issues such as scale and batch processing restrictions,low deposition rate,high energy consumption,and utilization of multiple environmentally hazardous *** address these challenges,we propose a stable and efficient wet chemical deposition coating method for high-throughput online continuous preparation of boron nitride(BN)coatings on ceramic fibers under an ambient *** process involves surface modification,in-situ wet chemical deposition,and heat treatment,and all seamlessly connecting with the ceramic fiber preparation process through continuous *** groups were introduced via surface modification enhancing wettability of the fiber surface with impregnating *** in-situ reaction and atom migration improve uniformity and binding of the *** a result,outstanding impregnation and adhesion properties are achieved.A comprehensive analysis to evaluate the impact of the BN coatings was conducted,which demonstrates that the BN-coated fibers exhibit a remarkable 36%increase in tensile strength,a 133%increase in fracture toughness,and enhanced temperature resistance of up to 1600℃.It provides a secure and efficient platform for cost-effective production of functional and high-quality coatings through targeted surface modification and rapid stretching impregnation.

关键词： polymer-derived ceramics SiC fibers wet chemical deposition atomic diffusion boron nitride(BN)coatings

Influence of Trailing-Edge Wear on the Vibrational Behavior of Wind Turbine Blades

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Fluid Dynamics & Materials Processing 2024年第2期20卷 337-348页

作者： Yuanjun Dai Xin Wei Baohua Li Cong Wang Kunju Shi mechanical college Shanghai Dian Ji UniversityShanghai201306China college of Energy engineering Xinjiang Institute of EngineeringUrumqi830091China

To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal *** to these experiments,the natural frequencies of trailing-edge worn blades-1,-2,and-3 increase the most in the second to fourth order,theﬁfth order increases in the middle,and theﬁrst order increases the *** damping ratio data indi-cate that,in general,theﬁrstﬁve-order damping ratios of trailing-edge worn blades-1 and trailing-edge worn blades-2 are reduced,and theﬁrstﬁve-order damping ratios of trailing-edge worn blades-3 are slightly *** mode shape diagram shows that the trailing-edge worn blades-1 and-2 have a large swing in the tip and the blade,whereas the second-and third-order vibration shapes of the trailing edge-worn blade-3 tend to be ***,all these results reveal that the blade’s mass and the wear area are the main fac-tors affecting the vibration characteristics of wind turbine blades.

关键词： Wind turbine modal test natural frequency damping ratio mode shape

Research and test of the measurement sensing device for the downforce of no-till planter row unit gauge wheels

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International Journal of Agricultural and Biological engineering 2024年第2期17卷 250-259页

作者： Jiajie Shang Liyi Liu Ruifeng Zhang Hongcheng Li Shouyin Hou Hongxin Liu Haitao Chen college of engineering Northeast Agricultural UniversityHarbin 150036China college of mechanical and Electrical engineering Suqian UniversitySuqian 223800JiangsuChina

To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method was proposed for monitoring the downforce through a two-dimensional radial sensing device,and a corresponding prototype was *** simulation analysis of the sensing device with ANSYS,a 45°angle was determined to exist between the strain gauge axis and the sensing device axis,and the Wheatstone bridging circuit of R1+R3−R5−R7(R stands for resistance strain gauge,different figures represent the strain gauge number)and R2+R4−R6−R8 was *** to performance and calibration tests for the sensing device,the maximum interaction effect between the X and Y axes was 2.52%,and the output signal was stable and *** standard error of the slope of the fitting equation of the downforce calculation model is *** to the field test,the average downforce of the gauge wheels was 1148,1017,843,and 713 N,at different sowing speeds of 6,8,10,and 12 km/h,*** coefficients of variation were 0.40,0.41,0.62,and 0.71,*** results indicate that the downforce fluctuation of the gauge wheels became more severe with increasing planting *** the strain simulation analysis and field test verified that the measurement method is accurate and reliable,the performance of the sensing device is stable,the measurement method and sensing device meet the application requirements and lay a foundation for the research of accurate and stable control of downforce of no-till planter.

关键词： no-till planter gauge wheel downforce two-dimensional radial force sensing device strain analysis measurement mode and method

Interactive mechanism and friction modelling of transient tribological phenomena in metal forming processes: A review

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Friction 2024年第3期12卷 375-395页

作者： Xiao YANG Heli LIU Lemeng ZHANG Yiran HU Denis J.POLITIS Mohammad M.GHARBI Liliang WANG Department of mechanical engineering Imperial College LondonLondon SW72AZUK Department of mechanical and Manufacturing engineering University of CyprusNicosia 1678Cyprus Quaker Houghton Deutschland GmbH Dortmund 44319Germany

The accurate representation of tribological boundary conditions at the tool–workpiece interface is crucial for analysis and optimization of formability,material flow,and surface quality of components during metal forming *** has been found that these tribological conditions vary spatially and historically with process parameters and contact *** time-dependent tribological behaviours are also known as transient tribological phenomena,which are widely observed during forming processes and many other manufacturing application ***,constant friction values are usually assigned to represent complex and dynamic interfacial conditions,which would introduce deviations in the relevant *** this paper,transient tribological phenomena and the contemporary understanding of the interaction between friction and wear are reviewed,and it has been found that these phenomena are induced by the transitions of friction mechanisms and highly dependent on complex loading conditions at the *** modelling techniques for transient behaviours for metal forming applications are also *** accurately describe the evolutionary friction values and corresponding wear during forming,the advanced interactive friction modelling has been established for different application scenarios,including lubricated condition,dry sliding condition(metal-on-metal contact),and coated system.

关键词： transient tribological phenomena interactive friction mechanism modelling techniques metal forming

Predicting the mechanical Behavior of a Bioinspired Nanocomposite through Machine Learning

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Computer Modeling in engineering & Sciences 2024年第8期140卷 1299-1313页

作者： Xingzi Yang Wei Gao Xiaodu Wang Xiaowei Zeng Department of mechanical engineering University of Texas at San AntonioSan AntonioTX78249USA Department of mechanical engineering Texas A&M UniversityCollege StationTX77843USA

The bioinspired nacre or bone structure represents a remarkable example of tough,strong,lightweight,and multifunctional structures in biological materials that can be an inspiration to design bioinspired high-performance *** bioinspired structure consists of hard grains and soft material *** the material interface has a very low volume percentage,its property has the ability to determine the bulk material *** learning technology nowadays is widely used in material science.A machine learning model was utilized to predict the material response based on the material interface properties in a bioinspired *** model was trained on a comprehensive dataset of material response and interface properties,allowing it to make accurate *** results of this study demonstrate the efficiency and high accuracy of the machine learning *** successful application of machine learning into the material property prediction process has the potential to greatly enhance both the efficiency and accuracy of the material design process.

关键词： Bioinspired nanocomposite computational model machine learning finite element material interface

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 Automotive 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 10 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

Web Layout Design of Large Cavity Structures Based on Topology Optimization

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Computer Modeling in engineering & Sciences 2024年第3期138卷 2665-2689页

作者： Xiaoqiao Yang Jialiang Sun Dongping Jin State Key Laboratory ofMechanics and Control for aerospace Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China

Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas become a focal point for contemporary researchers. Therefore, this paper aims to investigate the topologyoptimization of large cavity structures as a means to enhance their performance, safety, and efficiency. By usingthe variable density method, lightweight design is achieved without compromising structural strength. Theoptimization model considers both concentrated and distributed loads, and utilizes techniques like sensitivityfiltering and projection to obtain a robust optimized configuration. The mechanical properties are checked bycomparing the stress distribution and displacement of the unoptimized and optimized structures under the sameload. The results confirm that the optimized structures exhibit improved mechanical properties, thus offering keyinsights for engineering lightweight, high-strength large cavity structures.

关键词： Topology optimization lightweight design web layout design cavity structure

Safe Motion Planning and Control Framework for Automated Vehicles with Zonotopic TRMPC

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engineering 2024年第2期33卷 146-159页

作者： Hao Zheng Yinong Li Ling Zheng Ehsan Hashemi State Key Laboratory of mechanical Transmissions College of Mechanical and Vehicle EngineeringChongqing UniversityChongqing 400044China Department of mechanical engineering University of AlbertaEdmontonAB T6G 2H5Canada

Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning *** address this issue,this study proposes a safe motion planning and control(SMPAC)framework for *** the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller *** the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is *** safety sets provide the basis for the subsequent evaluation and ranking of the generated *** efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the *** result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.

关键词： Automated vehicles Automated driving Motion planning Motion control Tube MPC Zonotope

Bionic Design and Experimental Validation of a Robotic Airship Inspired by the Physalia physalis

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Journal of Bionic engineering 2024年第2期21卷 740-753页

作者： Yueneng Yang Lili Chen Zhiyang Liu Shifeng Zhang college of aerospace Science and engineering National University of Defense TechnologyNo.109Deya RoadKaiFu DistrictChangsha410073China aerospace Technology Institute China Aerodynamics Research and Development CenterMianyang621000China

The robotic airship is one of the most unique and promising green aircraft,however,as a“lighter-than-air aircraft”and“thermal aircraft”,its long-endurance flight has great difficulties in decreasing drag and controlling buoyancy and pressure under thermal *** this work,we reported a robotic airship inspired by the Physalia physalis,imitating its morphology,physiological structure,and biological *** hull is designed by imitating the morphology of the Physalia physalis,and the gasbags including a helium balloon,two ballonets,and a thermoregulation gasbag are designed by imitating the physiological structure and biological behaviors of the pneumatophore,bladder,and gland of the Physalia physalis,*** results show that the bionic airship has an increase of about 40%in lift-to-drag and decreases the pressure in helium balloon by 47.5%under thermal effects,and has better aerodynamic performances and thermoregulation performances than conventional airships.

关键词： Robotic airship Bionic design Aerodynamic performances Thermoregulation Physalia physalis