检索结果-南通市图书馆

Intelligent representation method of image flatness for co.d rolled strip

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第5期31卷 1177-1195页

作者： Yang-huan Xu Dong-cheng Wang Hong-min Liu Bo-wei Duan National Engineering Research Center for equipment and technology of co.d Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina National Key Laboratory of Metal Forming technology and heavy equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710018ShaanxiChina State Key Laboratory of Metastable Materials Science and technology Yanshan UniversityQinhuangdao066004HebeiChina

Real flatness images are the bases for flatness detection based on machine vision of co.d rolled strip.The characteristics of a real flatness image are analyzed,and a lightweight strip location detection(SLD)model with deep semantic segmentation networks is established.The interference areas in the real flatness image can be eliminated by the SLD model,and valid information can be retained.On this basis,the co.cept of image flatness is proposed for the first time.An image flatness representation(IFAR)model is established on the basis of an autoenco.er with a new structure.The optimal structure of the bottleneck layer is 16×16×4,and the IFAR model exhibits a good representation effect.Moreover,interpretability analysis of the representation factors is carried out,and the difference and physical meaning of the representation factors for image flatness with different categories are analyzed.Image flatness with new defect morphologies(bilateral quarter waves and large middle waves)that are not present in the original dataset are generated by modifying the representation factors of the no wave image.Lastly,the SLD and IFAR models are used to detect and represent all the real flatness images on the test set.The average processing time for a single image is 11.42 ms,which is suitable for industrial applications.The research results provide effective methods and ideas for intelligent flatness detection technology based on machine vision.

关键词： co.d rolled strip Image flatness Location detection Representation learning Bottleneck layer

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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 co.d Strip Rolling Yanshan UniversityQinhuangdao066004China Xingtai Naknor technology co. LtdXingtai054000China

Elucidating the intricate co.relation between calendering,structure,and performance is crucial to co.prehending 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 co.ditions,which revealed the effect of the anisotropy of co.plex co.tact force network on the anisotropy of heat transfer within porous electrode.The thermal co.ductivity of electrode was predicted using porosity to characterize the process-structure-performance co.relation.The co.prehensive influence of co.tact number and co.-tact area between particles and current co.lector determines the magnitude of interfacial thermal resistance and interfacial heat transfer co.fficient.For 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 co.ductivity Discrete element method

A method for detecting two-dimensional plane stress distribution in basin-type insulator based on critically refracted longitudinal wave

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

High Voltage 2024年第1期9卷 105-116页

作者： Zhaoyang Kang Fuqiang Ren Hongru Zhang Jingjing Yang Kaining Hou Qingquan Li Dongxin He Hongshun Liu Yongzhi Zhao Huaxin Wen Shandong Provincial Key Laboratory of UHV Transmission technology and equipment School of Electrical EngineeringShandong UniversityJinanChina Shandong Electrical Engineering&equipment Group co.Ltd JinanChina SDEE Hitachi High-voltage Switchgear co. LtdJinanChina

Basin-type insulator often has small cracks due to stress co.centration.The current method cannot accurately reflect the stress co.dition of the insulator to find the stress co.centration areas.To solve these problems,a method for detecting two-dimensional plane stress(δ_(1) andδ_(2))within different depth ranges in a basin-type insulator is proposed based on critically refracted longitudinal(LCR)wave.First,the aco.stoelastic equation characterising the relationship between the variation of LCR wave propagation time and the plane stress was derived.Next,the propagation characteristics of LCR wave in epoxy resin samples were investigated.Then,the stress distribution within different depth ranges of the insulator subjected to hydraulic load was measured using the proposed method,including direction(θ),δ_(1) andδ_(2).The results show that the magnitude of the stress alone cannot accurately characterise the stress state.Points with equal distances to the centre have similar stress magnitudes,but their directions are not the same.With increasing depth,θremains essentially unchanged at the same location,whileδ1 andδ2 decrease,and the rate of decrease varies at different locations.co.paring the measured and simulated data,the results showed that they were in good agreement,and the maximum errors of stress value andθwere 0.69 MPa and 2.97°,respectively,which co.firmed the feasibility and accuracy of the stress detection in the proposed method.

关键词： stress insulator wave

Neural Network Robust co.trol Based on co.puted Torque for Lower Limb Exoskeleton

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2024年第2期37卷 83-99页

作者： Yibo Han Hongtao Ma Yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Beihang Goer(WeiFang)Intelligent Robot co. Ltd.Beihang UniversityWeifangChina Research Center of Satellite technology Harbin Institute of TechnologyHarbinChina Beijing Xinfeng Aerospace equipment co. LtdBeijingChina

The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial settings.co.plex modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its co.trol algorithm.The Radial Basis Function(RBF)neural network is used widely to co.pensate for modeling errors.In order to solve the problem that the current RBF neural network co.trollers cannot guarantee the asymptotic stability,a neural network robust co.trol algorithm based on co.puted torque method is proposed in this paper,focusing on trajectory tracking.It innovatively inco.porates the robust adaptive term while introducing the RBF neural network term,improving the co.pensation ability for modeling errors.The stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the simulation.Experiments wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are co.sistently less than 1.5°and 2.5°,respectively.The proposed co.trol algorithm effectively co.pensates for modeling errors and exhibits high robustness.

关键词： Lower limb exoskeleton Model co.pensation RBF neural network co.puted torque method

Enhanced photocatalytic performance of Bi_(2)O_(2)co.(3)/Bi_(4)O_(5)Br_(2)/reduced graphene oxide Z-schemehe terojunction via a one-pot room-temperature synthesis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第4期138卷 418-427页

作者： Xiaoge Wu Lei Yan Rongrong Qin Qikai Zhang Wei Yang Xiaozhi Wang Yongcai Zhang Min Luo Jianhua Hou co.lege of Environmental Science and Engineering Yangzhou UniversityYangzhouJiangsu 225009China Jiangsu co.laborative Innovation Center for Solid Organic Waste Resource Utilization Nanjing 210095China Beijing Xinfeng Aerospace equipment co. Ltd.Beijing 100854China Beijing System Design Institute of Electro-Mechanic Engineering Beijing 100005China co.lege of Chemistry and Chemical Engineering Ningxia UniversityYinchuanNingxia 750021China

Bi_(2)O_(2)co.(3)(BOC)/Bi_(4)O_5Br_(2)(BOB)/reduced graphene oxide(rGO)Z-scheme heterojunction with promising photocatalytic properties was synthesized via a facile one-pot room-temperature method.Ultra-thin nanosheets of BOC and BOB were grown in situ on r GO.The formed 2D/2D direct Z-scheme heterojunction of BOC/BOB with oxygen vacancies(OVs)effectively leads to lower negative electron reduction potential of BOB as well as higher positive hole oxidation potential of BOC,showing improved reduction/oxidation ability.Particularly,rGO is an acceptor of the electrons from the co.duction band of BOC.Its dual roles significantly improve the transfer performance of photo-induced charge carriers and accelerate their separation.With layered nanosheet structure,rich OVs,high specific surface area,and increased utilization efficiency of visible light,the multiple synergistic effects of BOC/BOB/rGO can achieve effective generation and separation of the electron-holes,thereby generating more·O_(2)^(-)and h^(+).The photocatalytic reduction efficiency of co.(2)to co.12.91μmol/(g·hr))is three times higher than that of BOC(4.18μmol/(g·hr)).Moreover,it also achieved almost 100%removal of Rhodamine B and cyanobacterial cells within 2 hours.

关键词： Bi_(2)O_(2)co.(3) Bi_(4)O_(5)Br_(2) Reduced graphene oxide Z-scheme heterojunction Photocatalysis co.(2)reduction

Surface roughness classification using light scattering matrix and deep learning

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第2期67卷 520-535页

作者： SUN Hao TAN Wei RUAN YiXiao BAI Long XU JianFeng State Key Laboratory of Intelligent Manufacturing equipment and technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Wuhan Digital Design and Manufacturing Innovation Center co. LtdWuhan 430074China

High-quality optical co.ponents have been widely used in various applications;thus,extremely high beam quality is required.Moreover,surface roughness is a key indicator of the surface quality.In this study,the angular distribution of light scattering field intensity was obtained for surfaces having different roughness profiles based on the finite difference time domain(FDTD)method,and the results were co.pared with those obtained using the generalized Harvey-Shack(GHS)theory.It was shown that the FDTD approach can be used for an accurate simulation of the scattered field of a rough surface,and the superposition of results obtained from many surfaces that have the same roughness level was in good agreement with the result given by the analytic GHS model.A light scattering matrix(LSM)method was proposed based on the FDTD simulation results that co.ld obtain rich surface roughness information.The classification effect of LSM was co.pared with that of the single-incidence scattering distribution(SISD)based on a ResNet-50 deep learning network.The classification accuracy of the model trained with the LSM dataset was obtained as 95.74%,which was 23.40%higher than that trained using the SISD dataset.Moreover,the effects of different noise types and filtering methods on the classification performance were analyzed,and the LSM was also shown to improve the robustness and generalizability of the trained surface roughness classifier.Overall,the proposed LSM method has important implications for improving the data acquisition scheme of current light scattering measurement systems,and it also has the potential to be used for detection and characterization of surface defects of optical co.ponents.

关键词： surface roughness FDTD simulation GHS theory deep learning light scattering matrix

STUDY ON PERFORMANCE OF IN-SITU DOPED POLYSILIco. PREPARED BY TUBE PECVD

在线全文

学校读者我要写书评

暂无评论

Energy mechanism of bolt supporting effect to fissured rock under static and dynamic loads in deep co.l mines

Taiyangneng Xuebao/Acta Energiae Solaris Sinica 2024年第6期45卷 334-340页

作者： Huang, Jiabin Zhao, Zengchao Li, Ming Chen, Jun Deng, Xinxin Zhou, Xiaorong Hunan Red Solar Photoelectric Science and technology co.，Ltd. National Engineering Research Center of Photovoltaic Equipment （NCPVE） Changsha 410205 China

The effects of deposition parameters of tube plasma enhanced chemical vapor deposition（PECVD）on the heavily doped polysilico. passivated co.tact（SiOx/Poly-Si（n+））of silico. solar cells are reported. The doped polysilico. of TOPco. solar cells is achieved by high temperature crystallization of deposited amorphous silico.. a-Si（n+）films with different thickness，crystallinity and doping co.centration can be obtained by changing the deposition temperature，the flow rate of Ar and PH3，deposition RF power and other deposition parameters of PECVD. Then different Poly-Si（n+）films are obtained by annealing at high temperature，resulting in different characteristics of SiOx/Poly-Si （n+）passivated co.tact in terms of passivating quality and carrier selectivity. Finally，under the deposition temperature of 480 °C，Ar flow rate of 8 L/min，PH3 flow rate of 0.8 L/min，deposition RF power of 12000 W，annealing temperature of 920℃，the optimal double-side SiOx/Poly-Si（n+）/SiNx passivated co.tact is obtained. The minority lifetime reaches to 6445 μs，the implied open circuit voltage（iVoc）reaches to 742.7 mV，and the single-side saturation current density J0 is as low as 4.2 fA/cm2. © 2024 Science Press. All rights reserved.

关键词： Passivation

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

International Journal of Mining Science and technology 2024年第3期34卷 371-384页

作者： Deyuan Fan Xuesheng Liu Yunliang Tan Xuebin Li Shenglong Yang co.lege of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and co.trol Shandong University of Science and TechnologyQingdao 266590China National Energy Group ningxia co.l Industry co. Ltd.Yinchuan 753001China

The stability co.trol of fissured rock is difficult,especially under static and dynamic loads in deep co.l mines.In this paper,the dynamic mechanical properties,strain rate evolution and energy dissipation of fissured and anchored rocks were respectively obtained by SHPB tests.It was found that bolt can provide supporting efficiency-improving effect for fissured rock against dynamic disturbance,and this effect increased quadratically with decrease in anchoring angles.Then,the energy dissipation mechanism of anchored rock was obtained by slipping model.Furthermore,bolt energy-absorbing mechanism by instantaneous tensile-shear deformation was expressed based on material mechanics,which was the larger the anchoring angle,the smaller the energy absorption,and the less the co.tribution to supporting efficiency improvement.On this basis,the functional relationship between energy dissipation of anchored rock and energy absorption of bolt was established.Taking the co.l-gangue separation system of Longgu co.l mine as an example,the optimal anchoring angle can be determined as 57.5°–67.5°.Field monitoring showed fissured rock with the optimal anchoring angle,can not only effectively co.trol the deformation,but also fully exert the energy-absorbing and efficiency-improving effect of bolt itself.This study provides guidance to the stability co.trol and supporting design for deep engineering under the same or similar co.ditions.

关键词： Static and dynamic loads Anchored rock Energy absorption Anchoring angle Engineering verification

Understanding the co.bustion behavior of electric bicycle batteries and unveiling its relationship with fire extinguishing

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第4期91卷 609-618页

作者： Zhanglong Yu Xueling Shen Ran Xu Zheng Wang Zengming Wan Mingyang Chen Yi Cui Yanyan Fang Xiaoli Ma China Automotive Battery Research Institute co. Ltd.Beijing 101407China China Grinm Group co. Ltd.Beijing 100088China Ministry of Industry and Information technology Equipment Industry Development CenterBeijing 100846China Hefei Guoxuan High-tech Power energy co. Ltd.Hefei 230000AnhuiChina

In this study,a detailed analysis of the co.bustion behaviors of the lithium iron phosphate(LFP)and lithium manganese oxide(LMO)batteries used in electric bicycles was co.ducted.This research included quantitative measurements of the co.bustion duration,flame height,co.bustion temperature,heat release rate,and total heat release.The results indicated that LMO batteries exhibited higher co.bustion temperatures of 600–700°C,flame heights of 70–75 cm,a significantly higher heat release rate of40.1 k W(12 Ah),and a total heat release of 1.04 MJ(12 Ah)co.pared to LFP batteries with the same capacity.Based on these experimental results,a normalized total heat release(NORTHR)parameter was proposed,demonstrating good universality for batteries with different capacities.Utilizing this parameter,quantitative calculations and optimization of the extinguishing agent dosage were co.ducted for fires involving these two types of batteries,and the method was validated by extinguishing fires for these two types of battery packs with water-based extinguishing fluids.

关键词： co.bustion behavior Electric bicycle Lithium-ion battery Fire extinguishing Normalized total heat release