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True-temperature inversion algorithm for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization

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Nanotechnology and Precision engineering 2024年第1期7卷 55-62页

作者： Mei Liang Zhuo Sun Jiasong Liu Yongsheng Wang Lei Liang Long Zhang school of {1. and Automotive engineering Yantai UniversityYantai 264005China Liangshan Mining Co. Ltd.Huili 615141China

Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difﬁcult inversion problems with unknown ***-order calculus has the inherent advantage of easily jumping out of local extreme values;here,it is introduced into the particle-swarm algorithm to invert the true *** improved adaptive-adjustment mechanism is applied to automatically adjust the current velocity order of the particles and update their velocity and position values,increasing the accuracy of the true temperature *** results of simulations using the proposed algorithm were compared with three algorithms using typical emissivity models:the internal penalty function algorithm,the optimization function(fmincon)algorithm,and the conventional particle-swarm optimization *** results show that the proposed algorithm has good accuracy for true-temperature *** experimental results from a rocket-motor plume were used to demonstrate that the true-temperature inversion results of this algorithm are in good agreement with the theoretical true-temperature values.

关键词： Fractional-order particle swarm True-temperature inversion algorithm Multi-wavelength pyrometer

Theoretical and experimental research on static stiffness,performance,and lift-off characteristics of multi-layer gas foil thrust bearings

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Friction 2024年第11期12卷 2458-2479页

作者： Yang HU Pengjing DING Fangling WU Xiaojing WANG Bo LIANG Yonggang MENG school of Mechatronic {1. and Automation Shanghai UniversityShanghai 200072China Aviation Key Laboratory of Science and Technology on Aero electromechanical System Integration Nanjing Engineering Institute of Aircraft SystemsNanjing 211106China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

In this study,a new comprehensive fully coupled elastic–hydrodynamic model is developed for a multi-layer gas foil thrust bearing(GFTB).The interaction effects among the top foil,back board,middle foil,and bottom foil,as well as the Coulomb friction effect,are *** stiffness and static characteristics obtained by the experimental and theoretical approaches are in good agreement,which verifies the accuracy of the *** contribution of each foil layer to the overall stiffness and the load-carrying mechanism are *** effects of the load,preload,and rotational speed on the static performance are investigated ***,start–stop tests are performed to achieve the lift-off speed,start-up torque,and shut-down torque under various operating conditions.

关键词： multi-layer gas foil thrust bearing(GFTB) load carrying mechanism static performance

Structural energy storage composites based on modified carbon fiber electrode with metal-organic frame enhancing layered double hydroxide

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Nano Research 2024年第3期17卷 1552-1563页

作者： Jinrui Ye Zhongbao Wang Qin Lei Lei Sun Jinfeng Gu school of Aerospace {1. Beijing Institute of TechnologyBeijing 100081China Tangshan Research Institute Beijing Institute of TechnologyTangshan 063000China school of Materials Science and {1. Shenyang Jianzhu UniversityShenyang 110168China Department of Stomatology PLA Strategic Support Force Characteristic Medical CenterBeijing 100101China Beijing electromechanical {1. Research Institute Beijing 100074China

Structural energy storage composites present advantages in simultaneously achieving structural strength and electrochemical *** of carbon fiber electrodes and resin structural electrolytes in energy storage composite poses challenges in maintaining good mechanical and electrochemical properties at reasonable cost and ***,we report a simple method to fabricate structural supercapacitor using carbon fiber electrodes(modified by Ni-layered double hydroxide(Ni-LDH)and in-situ growth of Co-metal-organic framework(Co-MOF)in a two-step process denoted as Co-MOF/Ni-LDH@CF)and bicontinuous-phase epoxy resin-based structural ***-MOF/Ni-LDH@CF as electrode material exhibits improved specific capacity(42.45 F·g^(-1.)and cycle performance(93.3%capacity retention after 1.00 cycles)in a three-electrode *** bicontinuous-phase epoxy resin-based structural electrolyte exhibits an ionic conductivity of 3.27×1.^(-4) S·cm^(-1..The fabricated Co-MOF/Ni-LDH@CF/SPE-50 structural supercapacitor has an energy density of 3.21.Wh·kg^(-1. at a power density of 42.25 W·kg^(-1.,whilst maintaining tensile strength and modulus of 334.6 MPa and 25.2 *** results show practical potential of employing modified commercial carbon fiber electrodes and epoxy resin-based structural electrolytes in structural energy storage applications.

关键词： carbon fiber electrode structural electrolyte structural energy storage composites supercapacitor

3D-Printed Flat-Bone-Mimetic Bioceramic Scaffolds for Cranial Restoration

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Research 2024年第3期6卷 259-272页

作者： Yihang Zhang Fupo He Qiang Zhang Haotian Lu Shengtao Yan Xuetao Shi school of {1. engineering Guangdong University of TechnologyGuangzhou 510006P.R.China school of Materials Science and {1. South China University of TechnologyGuangzhou 510641P.R.China Peking Union Medical College Graduate school Bejing 100730P.R.China Department of Emergency China-Japan Friendship HospitalBeijing 100029P.R.China.

The limitations of autologous bone grafts necessitate the development of advanced biomimetic biomaterials for efficient cranial defect *** cranial bones are typical flat bones with sandwich structures,consisting of a diploe in the middle region and 2 outer compact *** this study,we originally developed 2 types of flat-bone-mimeticβ-tricalcium phosphate bioceramic scaffolds(Gyr-Comp and Gyr-Tub)by high-precision vat-photopolymerization-based 3-dimensional *** scaffolds had 2 outer layers and an inner layer with gyroid pores mimicking the diploe *** outer layers of Gyr-Comp scaffolds simulated the low porosity of outer tables,while those of Gyr-Tub scaffolds mimicked the tubular pore structure in the tables of flat *** Gyr-Comp and Gyr-Tub scaffolds possessed higher compressive strength and noticeably promoted in vitro cell proliferation,osteogenic differentiation,and angiogenic activities compared with conventional scaffolds with cross-hatch *** implantation into rabbit cranial defects for 1. weeks,Gyr-Tub achieved the best repairing effects by accelerating the generation of bone tissues and blood *** work provides an advanced strategy to prepare biomimetic biomaterials that fit the structural and functional needs of efficacious bone regeneration.

关键词： rabbit tables outer

Laser-assisted direct roller imprinting of large-area microstructured optical surfaces

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Microsystems & Nanoengineering 2024年第1期10卷 257-266页

作者： Keisuke Nagato Ken Takahashi Yuki Yajima Masayuki Nakao Department of Mechanical engineering Graduate School of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-8656Japan

In this study,a high-throughput fabrication method called laser-assisted direct roller imprinting(LADRI)was developed to lower the cost of nanoimprinting large-area polymer films and to address problems associated with nanoimprinting,namely,microstructural damage and precision in flatness of entire *** LADRI,the laser directly heats the microstructured surface of the roller mold,which heats and melts the surface of a polymethyl methacrylate(PMMA)film to replicate the microstructures on the mold *** this study,the effects of laser power density,scanning speed,size of the microstructures,and contact pressure on the replication speed were investigated *** replication speed increased as the power and scanning speed ***,because the film required heating until it filled the entire depth of the microstructure,an appropriate replication speed was *** result was supported by simulation of the temperature distribution inside the mold and the PMMA using transient heat conduction *** demonstrate the applications of LADRI,two different optical surfaces were replicated:an antireflection(AR)structure with conical structures sized several hundred nanometers and a lightextraction structure with a microlens array(MLA)comprising 1.μm lenses,for display and illumination,*** replication degree of the MLA was governed by the contact *** flow simulation indicated that the heat conduction and flow speeds of the melted PMMA surface were comparable within several tens of *** addition,the reflectivity of the AR structure decreased from 4 to 0.5%,and the light intensity of the light-extraction structure increased by a factor of 1.47.

关键词： microstructure roller conduction

Precipitates Generation Mechanism and Surface Quality Improvement for Aluminum Alloy 6061.in Diamond Cutting

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 150-159页

作者：王海龙 DENG Wenping 王素娟 State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of Micro-Nano Manufacturing Technology and Equipment School of Electromechanical EngineeringGuangdong University of TechnologyGuangzhou 510006China

To improve the surface quality for aluminum alloy 6061.Al6061. in ultra-precision machining, we investigated the factors affecting the surface finish in single point diamond turning(SPDT)by studying influence of the precipitates generation of Al6061.on surface integrity and surface *** on the Johnson-Mehl-Avrami solid phase transformation kinetics equation, theoretical and experimental studies were conducted to build the relationship between the aging condition and the type, size and number of the precipitates for Al6061. Diamond cutting experiments were conducted to machine Al6061.samples under different aging conditions. The experimental results show that, the protruding on the chip surface is mainly Mg_(2)Si and the scratches on the machined surface mostly come from the iron-containing phase(α-, β-AlFeSi).Moreover, the generated Mg_(2)Si and α-, β-AlFeSi affect the surface integrity and the diamond turned surface roughness. Especially, the achieved surface roughness in SPDT is consistent with the variation of the number of AlFeSi and Mg_(2)Si with the medium size(more than 1.μm and less than 2 μm) in Al6061.

关键词： Al6061 precipitates aging treatment diamond cutting surface roughness

Synchronous organic-inorganic co-intercalated ammonium vanadate cathode for advanced aqueous zinc-ion batteries

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Journal of Energy Chemistry 2024年第7期94卷 608-617页

作者： Wenpei Kang Bingchen Zhang Zhurui Wang Zhengchunyu Zhang Mang Niu Xuguang An Zhenkai Mou Xiaoyu Fan Xuqiang Hu Baojuan Xi Shenglin Xiong school of Materials Science and {1. China University of Petroleum(East China)Qingdao 266580ShandongChina school of Chemistry and Chemical {1. Shandong UniversityJinan 250100ShandongChina State Key Laboratory of Bio-fibers and Eco-textiles Institute of Biochemical Engineering College of Materials Science and EngineeringQingdao UniversityQingdao 266071ShandongChina school of Mechanical {1. Chengdu UniversityChengdu 610106SichuanChina Received 1 February 2024Revised 1 March

Vanadium-based cathode materials are attractive for aqueous zinc-ion batteries(AZIBs)owing to the high capacity from their open frameworks and multiple ***,the cycle stability and rate capability are still restricted by the low electrical conductivity and trapped diffusion ***,we propose an organic-inorganic co-intercalation strategy to regulate the structure of ammonium vanadate(NH_(4)V_(4)O_(1.),NVO).The introduction of Al^(3+)and polyaniline(PANI)induces the optimized layered structure and generation of urchin-like hierarchical construction(AP-NVO),based on heterogeneous nucleation and dissolution-recrystallization growth *** to these favorable features,the AP-NVO electrode delivers a desirable discharge capacity of 386 mA h g^(-1. at 1.0 A g^(-1.,high-rate capability of 263 mA h g^(-1.)at 5.0 A g^(-1. and excellent cycling stability with 80.4%capacity retention over 2000 cycles at 5.0 A g^(-1..Such satisfactory electrochemical performance is believed to result from the enhanced reaction kinetics provided by the stable layered structure and a high intercalation pseudo-capacitance *** results could provide enlightening insights into the design of layered vanadium oxide cathodematerials.

关键词： Ammonium vanadate bronze Co-pre-intercalation Urchin-like hierarchical structure Aqueous zinc-ion batteries

Protective performance of shear stiffening gel-modified foam against ballistic impact:Experimental and numerical study

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Defence Technology（防务技术） 2024年第2期32卷 510-520页

作者： Huan Tu Haowei Yang Pengzhao Xu Zhe Yang Fan Tang Cheng Dong Yuchao Chen Lei Ren Wenjian Cao Chenguang Huang Yacong Guo Yanpeng Wei Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China school of Mechanical {1. Northwestern Polytechnical UniversityXi'an 710072China Xi'an Institute of electromechanical Information Technology Xi'an 710065China Science and Technology on Transient Impact Laboratory Beijing 102202China school of {1. Science University of Chinese Academy of SciencesBeijing 100049China

As one of the most widely used personal protective equipment(PPE),body armors play an important role in protecting the human body from the high-velocity impact of bullets or *** body torso and critical organs of the wear may suffer severe behind-armor blunt trauma(BABT)even though the impactor is stopped by the body armor.A type of novel composite material through incorporating shear stiffening gel(STG)into ethylene-vinyl acetate(EVA)foam is developed and used as buffer layers to reduce *** this paper,the protective performance of body armors composed of fabric bulletproof layers and a buffer layer made of foam material is investigated both experimentally and *** effectiveness of STG-modified EVA in damage relief is verified by ballistic *** parallel with the experimental study,numerical simulations are conducted by LS-DYNA®to investigate the dynamic response of each component and capture the key mechanical parameters,which are hardly obtained from field *** fully describe the material behavior under the transient impact,the selected constitutive models take the failure and strain rate effect into consideration.A good agreement between the experimental observations and numerical results is achieved to prove the validity of the modelling *** tests and simulations show that the impact-induced deformation on the human body is significantly reduced by using STG-modified EVA as the buffering *** improvement of protective performance is attributed to better dynamic properties and more outstanding energy absorption capability of the composite foam.

关键词： Ballistic behavior Composite foam Shear stiffening gel Finite element analysis Protective mechanism

Noise-Tolerant ZNN-Based Data-Driven Iterative Learning Control for Discrete Nonaffine Nonlinear MIMO Repetitive Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 344-361页

作者： Yunfeng Hu Chong Zhang Bo Wang Jing Zhao Xun Gong Jinwu Gao Hong Chen State Key Laboratory of Automotive Simulation and Control Jilin UniversityJilin UniversityChangchun 130025China College of Communication engineering Jilin UniversityJilin UniversityChangchun 130025China Department of electromechanical {1. University of MacaoMacao 999078China school of Artificial Intelligence Jilin UniversityChangchun 130012China IEEE College of Electronics and Information engineering Tongji UniversityShanghai 200092China

Aiming at the tracking problem of a class of discrete nonaffine nonlinear multi-input multi-output(MIMO) repetitive systems subjected to separable and nonseparable disturbances, a novel data-driven iterative learning control(ILC) scheme based on the zeroing neural networks(ZNNs) is proposed. First, the equivalent dynamic linearization data model is obtained by means of dynamic linearization technology, which exists theoretically in the iteration domain. Then, the iterative extended state observer(IESO) is developed to estimate the disturbance and the coupling between systems, and the decoupled dynamic linearization model is obtained for the purpose of controller synthesis. To solve the zero-seeking tracking problem with inherent tolerance of noise,an ILC based on noise-tolerant modified ZNN is proposed. The strict assumptions imposed on the initialization conditions of each iteration in the existing ILC methods can be absolutely removed with our method. In addition, theoretical analysis indicates that the modified ZNN can converge to the exact solution of the zero-seeking tracking problem. Finally, a generalized example and an application-oriented example are presented to verify the effectiveness and superiority of the proposed process.

关键词： Adaptive control control system synthesis data-driven iterative learning control neurocontroller nonlinear discrete time systems