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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 173-174页

作者： Yongmin Liu department of mechanical and Industrial engineering Northeastern UniversityBoston 02115USA department of Electrical and Computer engineering Northeastern UniversityBoston 02115USA

Effective medium theory(EMT)has been widely applied in material science,electromagnetics and photonics to determine the effective material properties for inhomogeneous composites comprising subwavelength *** versatility of this foundational approach has been established through its application in classical Maxwell-Garnet models,which encompass relatively simple structures。

关键词： composites theory dielectric

Comparative analysis on the performance of different types of input-and command-shaping controllers in minimizing payload residual vibration of an overhead crane with an inclined supporting track

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International Journal of mechanical System Dynamics 2024年第1期4卷 22-33页

作者： Mohammed Alfares Khaled Alhazza mechanical engineering department College of Engineering and PetroleumKuwait UniversityKuwait CityKuwait

Reducing the effects of external disturbance on overhead crane systems is crucial,as they can impair the controller performance and cause excessive vibrations or oscillations of the *** such external disturbance is the inclination of the supporting track of the crane trolley,which causes the system dynamics model to *** open-loop control strategy is widely utilized to control the payload sway motion and generally does not require any alterations in the physical structure of a system or the installation of sensors and/or *** and command shaping are two common open-loop control techniques applied to control overhead *** this paper,the effect of moving an overhead crane system along an inclined supporting track is *** addition,the ability of different types of input-and command-shaping control schemes to suppress the residual vibrations due to trolley track inclination is *** types of input-shaping controllers,which are double-step,zero vibration,and one command waveform(WF)shaper based on a trigonometric function,are used and tested.A linear equation of motion of the overhead crane resting on an inclined surface is developed to simulate the overhead crane and payload *** effectiveness of the different types of open-loop controllers to suppress residual vibrations is verified by both simulation and experimental *** addition,a new WF command shaper is proposed and designed to overcome track inclination while eliminating payload residual vibration.A comprehensive comparative analysis,both numerically and experimentally,is performed on the new proposed shaper to measure its effectiveness in handling inclination when compared to other types of open-loop *** new shaper outperforms other controllers in eliminating payload residual vibration for a wider range of inclination angles.

关键词： overhead cranes open-loop control input and command shaping payload residual vibrations

An introductory review of swarm technology for spacecraft on-orbit servicing

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International Journal of mechanical System Dynamics 2024年第1期4卷 3-21页

作者： El Ghali Asri Zheng H.Zhu department of mechanical engineering York UniversityTorontoOntarioCanada

This review paper presents a comprehensive evaluation and forward-looking perspective on the underexplored topic of servicing target objects using spacecraft *** targets can be known or unknown,cooperative or uncooperative,and pose significant challenges in modern space operations due to their inherent complexity and *** servicing space objects is vital for active debris removal and broader on-orbit servicing tasks such as satellite maintenance,repair,refueling,orbital assembly,and *** effort has been invested in the literature to explore the servicing of targets using a single *** its advantages and benefits,this paper expands the discussion to encompass a swarm approach to the *** review covers various single-spacecraft approaches and presents a critical examination of the existing,although limited,body of work dedicated to servicing orbital objects using multiple *** focus is also broadened to include some influential studies concerning the characterization,capture,and manipulation of physical objects by general multiagent systems,a subject with significant parallels to the core interest of this ***,this article also delves into the realm of simultaneous localization and mapping,highlighting its application within close-proximity operations in space,especially when dealing with unknown uncooperative *** attention is paid to the benefits that this field can receive from distributed multiagent ***,an exploration of the promising field of swarm robotics is presented,with an emphasis on its potential to revolutionize the servicing of orbital target ***,a survey of general research directly engaging swarms in the orbital context is *** review aims to bridge the knowledge gap and stimulate further research in the underexplored domain of servicing space targets with spacecraft swarms.

关键词： space robotics on-orbit servicing close-proximity operations guidance and navigation swarm robotics multiagent systems object capture and manipulation simultaneous localization and mapping

The Effect of Uncaria gambir on Optical Properties and Thermal Stability of CNF/PVA Biocomposite Films

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Journal of Renewable Materials 2024年第9期12卷 1593-1603页

作者： Remon Lapisa Anna Niska Fauza Dieter Rahmadiawan Krismadinata Dori Yuvenda Randi Purnama Putra Waskito Nandy Putra Hairul Abral mechanical engineering department Universitas Negeri PadangPadang25173Indonesia Centre for Energy and Power Electronics Research Universitas Negeri PadangPadang25173Indonesia department of mechanical engineering National Cheng Kung University(NCKU)Tainan70101Taiwan mechanical engineering department Universitas IndonesiaDepok16424Indonesia mechanical engineering department Universitas AndalasPadang25163Indonesia

Cellulose-based film has gained popularity as an alternative to synthetic polymers due to its outstanding *** all types of cellulose materials available,cellulose nanofiber(CNF)has great potential to be utilized in a diverse range of applications,including as a film *** this study,CNF biocomposite film was prepared by using polyvinyl alcohol(PVA)as a matrix and Uncaria gambir extract as a *** study aims to investigate the effect of Uncaria gambir extract on the optical properties and thermal stability of the produced *** formation of the CNF biocomposite films was confirmed using Fourier Transform Infrared Spectroscopy,their transmittance characteristics were measured using UV-Vis spectroscopy and a transmittance meter,while their reflectance was determined using a reflectance *** results revealed that the addition of Uncaria gambir extract to the CNF biocomposite film improved its UV-shielding properties,as indicated by the lower percentage of transmittance in the visible region,10%–70%.In addition,its reflectance increased to 10.6%compared to the CNF film without the addition of Uncaria gambir ***,the thermal stability of the CNF biocomposite film with the addition of Uncaria gambir extract improved to around 400℃–500℃.In conclusion,the results showed that CNF biocomposite film prepared by adding Uncaria gambir extract can be a promising candidate for optical and thermal management materials.

关键词： Cellulose nanofiber biocomposite film optical properties Uncaria gambir thermal stability

Deep neural network-enabled battery open-circuit voltage estimation based on partial charging data

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Journal of Energy Chemistry 2024年第3期90卷 120-132,I0005页

作者： Ziyou Zhou Yonggang Liu Chengming Zhang Weixiang Shen Rui Xiong State Key Laboratory of mechanical Transmission for Advanced Equipment&College of mechanical and Vehicle engineering Chongqing UniversityChongqing 400000China department of Vehicle engineering School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China department of Electrical engineering Harbin Institute of TechnologyHarbin 150000HeilongjiangChina School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthornVictoria 3122Australia

Battery management systems(BMSs) play a vital role in ensuring efficient and reliable operations of lithium-ion *** main function of the BMSs is to estimate battery states and diagnose battery health using battery open-circuit voltage(OCV).However,acquiring the complete OCV data online can be a challenging endeavor due to the time-consuming measurement process or the need for specific operating conditions required by OCV estimation *** addressing these concerns,this study introduces a deep neural network-combined framework for accurate and robust OCV estimation,utilizing partial daily charging *** incorporate a generative deep learning model to extract aging-related features from data and generate high-fidelity OCV *** analysis is employed to identify the optimal partial charging data,optimizing the OCV estimation precision while preserving exceptional *** validation results,using data from nickel-cobalt-magnesium(NCM) batteries,illustrate the accurate estimation of the complete OCV-capacity curve,with an average root mean square errors(RMSE) of less than 3 *** this level of precision for OCV estimation requires only around 50 s collection of partial charging *** validations on diverse battery types operating under various conditions confirm the effectiveness of our proposed *** cases of precise health diagnosis based on OCV highlight the significance of conducting online OCV *** method provides a flexible approach to achieve complete OCV estimation and holds promise for generalization to other tasks in BMSs.

关键词： Lithium-ion battery Open-circuit voltage Health diagnosis Deep learning

Microstructure transformations and improving wear resistance of austenitic stainless steel additively fabricated by arc-based DED process

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Defence Technology（防务技术） 2024年第8期38卷 194-204页

作者： Ashish Yadav Manu Srivastava Prashant K.Jain Sandeep Rathee Hybrid Additive Manufacturing Laboratory Mechanical Engineering DepartmentPDPM Indian Institute of Information TechnologyDesign&ManufacturingJabalpur482005Madhya PradeshIndia FFF Laboratory Mechanical Engineering DepartmentPDPM Indian Institute of Information TechnologyDesign&ManufacturingJabalpur482005Madhya PradeshIndia department of mechanical engineering National Institute of TechnologySrinagarIndia

In this study, austenitic stainless steel(ASS) was additively fabricated by an arc-based direct energy deposition(DED) technique. Macrostructure, microstructure, mechanical characteristics at different spatial orientations(0°, 90°, and 45°), and wear characteristics were evaluated at the deposited structure top, middle, and bottom regions. Results show that austenite(γ) and delta-ferrite(δ) phases make up most of the microstructure of additively fabricated SS316LSi steel. Within γ matrix, δ phase is dispersed both(within and along) grain boundaries, exhibiting a fine vermicular morphology. The bottom, middle,and top regions of WAAM deposited ASS exhibit similar values to those of wrought SS316L in the tensile and impact test findings. Notably, a drop in hardness values is observed as build height increases. During SEM examinations of fractured surfaces from tensile specimen, closed dimples were observed, indicating good ductility of as-built structure. Wear test findings show signs of mild oxidation and usual adhesive wear. By depositing a mechanically mixed composite layer, an increase in the oxidation percentage was discovered to facilitate healing of worn surfaces. The findings of this study will help in design, production and renovation of products/components that are prone to wear. WAAM-deposited ASS has remarkable strength and ability to withstand impacts;it can be used in the production of armour plates for defence applications, mainly military vehicles and aircraft.

关键词： Metal additive deposition Defence applications Arc-based DED Characterization Wear behaviour Fractography

Generating synthetic as-built additive manufacturing surface topography using progressive growing generative adversarial networks

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Friction 2024年第6期12卷 1283-1298页

作者： Junhyeon SEO Prahalada RAO Bart RAEYMAEKERS department of mechanical engineering Virginia TechBlacksburgVA 24061USA Grado department of Industrial and Systems engineering Virginia TechBlacksburgVA 24061USA

Numerically generating synthetic surface topography that closely resembles the features and characteristics of experimental surface topography measurements reduces the need to perform these intricate and costly ***,existing algorithms to numerically generated surface topography are not well-suited to create the specific characteristics and geometric features of as-built surfaces that result from laser powder bed fusion(LPBF),such as partially melted metal particles,porosity,laser scan lines,and ***,we present a method to generate synthetic as-built LPBF surface topography maps using a progressively growing generative adversarial *** qualitatively and quantitatively demonstrate good agreement between synthetic and experimental as-built LPBF surface topography maps using areal and deterministic surface topography parameters,radially averaged power spectral density,and material ratio *** ability to accurately generate synthetic as-built LPBF surface topography maps reduces the experimental burden of performing a large number of surface topography ***,it facilitates combining experimental measurements with synthetic surface topography maps to create large data-sets that facilitate,*** as-built surface topography to LPBF process parameters,or implementing digital surface twins to monitor complex end-use LPBF parts,amongst other applications.

关键词： additive manufacturing surface topography synthetic surface topography generative adversarial networks

Interplay between temperature-dependent strengthening mechanisms and mechanical stability in high-performance austenitic stainless steels

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2182-2188页

作者： Mohammad Javad Sohrabi Hamed Mirzadeh Saeed Sadeghpour Milad Zolfipour Aghdam Abdol Reza Geranmayeh Reza Mahmudi School of Metallurgy and Materials engineering College of EngineeringUniversity of Tehran14395-515 TehranIran Centre for Advanced Steels Research Materials and Mechanical EngineeringUniversity of Oulu90014 OuluFinland department of mechanical engineering College of EngineeringUniversity of Tehran14395-515 TehranIran

The effects of deformation temperature on the transformation-induced plasticity(TRIP)-aided 304L,twinning-induced plasti-city(TWIP)-assisted 316L,and highly alloyed stable 904L austenitic stainless steels were compared for the first time to tune the mechan-ical properties,strengthening mechanisms,and strength-ductility *** this purpose,the scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),X-ray diffraction(XRD),tensile testing,work-hardening analysis,and thermodynamics calcu-lations were *** induced plasticity effects led to a high temperature-dependency of work-hardening behavior in the 304L and 316L stainless *** the deformation temperature increased,the metastable 304L stainless steel showed the sequence of TRIP,TWIP,and weakening of the induced plasticity mechanism;while the disappearance of the TWIP effect in the 316L stainless steel was also ***,the solid-solution strengthening in the 904L superaustenitic stainless steel maintained the tensile properties over a wide temper-ature range,surpassing the performance of 304L and 316L stainless *** this regard,the dependency of the total elongation on the de-formation temperature was less pronounced for the 904L alloy due to the absence of additional plasticity *** results re-vealed the importance of solid-solution strengthening and the associated high friction stress for superior mechanical behavior over a wide temperature range.

关键词： austenitic stainless steels mechanical behavior stacking fault energy metastability mechanical twinning

Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis

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Journal of Energy Chemistry 2024年第4期91卷 522-541页

作者： Sungsoon Kim Dongjae Kong Xiaolin Zheng Jong Hyeok Park department of Chemical&Biomolecular engineering Yonsei UniversitySeoul 03722Republic of Korea department of mechanical engineering Stanford UniversityStanfordCA 94305USA

Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern ***,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only 9%,has led to a monumental environmental *** recycling has emerged as a vital response to this crisis,offering sustainable solutions to mitigate its environmental *** these recycling efforts,plastic upcycling has garnered attention,which elevates discarded plastics into higher-value ***,electrocatalytic and photoelectrocatalytic treatments stand at the forefront of advanced plastic *** or photoelectrocatalytic treatments involve chemical reactions that facilitate electron transfer through the electrode/electrolyte interface,driven by electrical or solar energy,*** methods enable precise control of chemical reactions,harnessing potential,current density,or light to yield valuable chemical *** review explores recent progress in plastic upcycling through electrocatalytic and photoelectrocatalytic pathways,offering promising solutions to the plastic waste crisis and advancing sustainability in the plastics industry.

关键词： Plastic upcycling Electrocatalytic reaction Photoelectrocatalytic reaction Value-added product

Techno-Economic Optimization of Novel Stand-Alone Renewable Based Electric Vehicle Charging Station near Bahria Town Karachi,Sindh Pakistan

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Energy engineering 2024年第6期121卷 1439-1457页

作者： Aneel Kumar Mahesh Kumar Amir Mahmood Soomro Laveet Kumar department of Electrical engineering Mehran University of Engineering and TechnologyJamshoroPakistan department of mechanical engineering Mehran University of Engineering and TechnologyJamshoroPakistan

Electric vehicles (EVs) are the most interesting and innovative technology in the 21st century because of theirenormous advantages, both technically and economically. Their emissions rate compared to fuel-based vehicles isnegligible as they do not consume fuel and hence do not emit any harmful gases. However, their bulk production,adoption and lack of charging stations increase the stress of power stations due to modern-day lifestyles. If Electricvehicles demand increases drastically then conventional power stations will not bear their demand and if theygenerate electricity by conventional means it will be very costly and may further add greenhouse gases. Therefore,this research provides the techno-economic assessment of a stand-alone renewable-dependent electric vehiclecharging station, excluding any burden on electrical utility. The proposed study is carried out in Bahria Town,Karachi, a city in Pakistan. In this study, HOMER Pro software was utilized for techno-economic assessment. Ahybrid system comprising solar Photovoltaic/Wind Turbine/Fuel cells and battery storage is included in the *** and wind resources were taken from NASA’s website, where charging stations will be integrated. The overallresults show promising in terms of total Net Present Cost and the Cost of Energy which are 2.72M $ and 0.237 $,respectively. The total system generation is 3,598 Megawatt hours per year, and the total energy consumption is 885Megawatt hours per year.

关键词： Electrical vehicle techno economic analysis solar energy wind energy hydrogen energy