检索结果-南通市图书馆

Intelligent representation method of image flatness for cold 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 Cold 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 cold rolled *** characteristics of a real flatness image are analyzed,and a lightweight strip location detection(SLD)model with deep semantic segmentation networks is *** interference areas in the real flatness image can be eliminated by the SLD model,and valid information can be *** this basis,the concept of image flatness is proposed for the first *** image flatness representation(IFAR)model is established on the basis of an autoencoder with a new *** optimal structure of the bottleneck layer is 16×16×4,and the IFAR model exhibits a good representation ***,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 *** 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 ***,the SLD and IFAR models are used to detect and represent all the real flatness images on the test *** average processing time for a single image is 11.42 ms,which is suitable for industrial *** research results provide effective methods and ideas for intelligent flatness detection technology based on machine vision.

关键词： Cold rolled strip Image flatness Location detection Representation learning Bottleneck layer

Inhibiting plastic tensile instability of non-symmetric thin-walled shell component via increasing regional metal inflow based on heterogeneous pressure-carrying medium

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 Aeronautics 2024年第1期37卷 391-413页

作者： Nan XIANG Yiquan SHU Pengyi WANG Menghan YANG Haoran WANG Tao HUANG Junqing GUO Fuxiao CHEN School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Key Laboratory for Precision Heat Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China College of Mechanical&Electrical Engineering Shaanxi University of Science&TechnologyXi’an 710021China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal new Materials and Advanced Processing technology Luoyang 471023China

Heterogeneous pressure-carrying medium was employed to establish a differentiated pressure field on sheet metal in flexible die forming process in this work,which aimed at matching the non-symmetric shape of target component and improving metal inflow to avoid local tensile ***,metal inflow corresponding to the differentiated pressure field was analytically *** of a typical non-symmetric shell component was experimentally and numerically studied based on the proposed *** with forming processes based on the uniform pressure,difference of metal inflow in two sides of the non-symmetric component increased from 2.16 mm to 3.36 mm and metal inflow in critical region increased by 11.9%when differentiated pressure field(taking heterogeneous elastomer#4–3 for example)was *** resultant maximum thinning ratio decreased by 4.2% and the uniformity of shell thickness increased by 16.9%.With the decrease of Shore hardness of elastomer in the formed region,stress path in the ready-to-form region transferred towards the bi-axial tension stress state,i.e.,stress ratio(a)***,stress triaxiality(η)in characteristic regions were regulated appropriately,which decreased the risk of tensile *** was attributed to the decreased normal pressure and frictional resistance at sheet/elastomer interface in the formed region.

关键词： Aluminum alloys Finite element method Metal forming Plastic deformation Sheet metal

Absorption properties and mechanism of lightweight and broadband electromagnetic wave-absorbing porous carbon by the swelling treatment

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1701-1712页

作者： Jianghao Wen Di Lan Yiqun Wang Lianggui Ren Ailing Feng Zirui Jia Guanglei Wu College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China institute of Physics&Optoelectronics technology Baoji University of Arts and SciencesBaoji 721016China

Bioderived carbon materials have garnered considerable interest in the fields of microwave absorption and shielding due to their reproducibility and environmental *** this study,KOH was evenly distributed on biomass Tremella using the swelling induction method,leading to the preparation of a three-dimensional network-structured hierarchical porous carbon(HPC)through *** achieved microwave absorption intensity is robust at-47.34 dB with a thin thickness of 2.1 ***,the widest effective absorption bandwidth,reaching 7.0 GHz(11–18 GHz),is attained at a matching thickness of 2.2 *** exceptional broadband and reflection loss performance are attributed to the 3D porous networks,interface effects,carbon network defects,and dipole *** has outstanding absorption characteristics due to its excellent impedance matching and high attenuation *** uniform pore structures considerably optimize the impedance-matching performance of the material,while the abundance of interfaces and defects enhances the dielectric loss,thereby improving the attenuation ***,the impact of carbonization temperature and swelling rate on microwave absorption performance was systematically *** research presents a strategy for preparing absorbing materials using biomass-derived HPC,showcasing considerable potential in the field of electromagnetic wave absorption.

关键词： biomass hierarchical porous carbon dielectric loss electromagnetic wave absorption

Online diagnosis platform for tomato seedling diseases in greenhouse production

在线全文

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2024年第1期17卷 80-89页

作者： Xin Jin Xiaowu Zhu Jiangtao Ji Mingyong Li Xiaolin Xie Bo Zhao College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina Science&technology Innovation Center for Completed Set Equipment Longmen LaboratoryLuoyang 471023HenanChina institute of Mechatronics technology and Application China Mechanized Agriculture Science Research Institute Group Co.LtdBeijing 100020China

The facility-based production method is an important stage in the development of modern agriculture,lifting natural light and temperature restrictions and helping to improve agricultural production *** address the problems of difficulty and low accuracy in detecting pests and diseases in the dense production environment of tomato facilities,an online diagnosis platform for tomato plant diseases based on deep learning and cluster fusion was proposed by collecting images of eight major prevalent pests and diseases during the growing period of tomatoes in a facility-based *** diagnostic platform consists of three main parts:pest and disease information detection,clustering and decision-making of detection results,and platform diagnostic ***,based on the You Only Look Once(YOLO)algorithm,the key information of the disease was extracted by adding attention module(CBAM),multi-scale feature fusion was performed using weighted bi-directional feature pyramid network(BiFPN),and the overall construction was designed to be compressed and lightweight;Secondly,the k-means clustering algorithm is used to fuse with the deep learning results to output pest identification decision values to further improve the accuracy of identification applications;Finally,a detection platform was designed and developed using Python,including the front-end,back-end,and database of the system to realize online diagnosis and interaction of tomato plant pests and *** experiment shows that the algorithm detects tomato plant diseases and insect pests with mAP(mean Average Precision)of 92.7%,weights of 12.8 Megabyte(M),inference time of 33.6 *** with the current mainstream single-stage detection series algorithms,the improved algorithm model has achieved better performance;The accuracy rate of the platform diagnosis output pests and diseases information of 91.2%for images and 95.2%for *** is a great significance to tomato pest control research and t

关键词： pest and disease detection YOLO diagnosis platform k-means clustering facility production base

Angle-resolved photoemission study of NbGeSb with non-symmorphic symmetry

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 Physics B 2024年第2期33卷 464-470页

作者：马欢谭宁吴徐传李满王义炎路洪艳夏天龙王善才 Department of Physics Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education)Renmin University of ChinaBeijing 100872China Beijing Key Laboratory of Opto-Electronic Functional Materials&Micro-Nano Devices Renmin University of ChinaBeijing 100872China School of Information Network Security People’s Public Security University of ChinaBeijing 100038China institute of Physical Science and Information technology Anhui UniversityHefei 230601China School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China

We investigate the electronic structure of NbGeSb with non-symmorphic *** employ angle-resolved photoemission spectroscopy(ARPES)to observe and identify the bulk and surface states over the Brillouin *** utilizing high-energy photons,we identify the bulk Fermi surface and bulk nodal line along the direction X–R,while the Fermi surface of the surface state is observed by using low-energy *** observe the splitting of surface bands away from the high-symmetry point *** density functional theory calculations on bulk and 1 to 5-layer slab models,as well as spin textures of NbGeSb,verify that the band splitting could be attributed to the Rashba-like spin–orbit coupling caused by space-inversion-symmetry breaking at the *** splitted surface bands cross with each other,forming two-dimensional Weyl-like crossings that are protected by mirror *** findings provide insights into the two-dimensional topological and symmetry-protected band inversion of surface states.

关键词： non-symmorphic symmetry nodal line splitting of surface bands angle-resolved photoemission spectroscopy

Hybrid Additive Manufacturing of forming Tools

在线全文

学校读者我要写书评

暂无评论

Automotive Innovation 2023年第3期6卷 311-323页

作者： Hamed Dardaei Joghan Ramona Holker‑Jager Anna Komodromos A.Erman Tekkaya institute of forming technology and lightweight Components(IUL) TU Dortmund UniversityBaroper Stra.e 30344227 DortmundGermany

Additive manufacturing(AM)is widely used in the automotive industry and has been expanded to include aerospace,marine,and *** flexibility and the possibility of manufacturing complex parts in AM motivate the integration of additive manu-facturing with classical forming technologies,which can improve tooling concepts and reduce *** study presents three applications of this ***,the possibility of successful utilization of selective laser melting for manufacturing extrusion tools with complex cooling channels and paths for thermocouples is reported,leading to significantly reduced inner die temperatures during the extrusion ***,sheet lamination is integrated with laser metal deposition(LMD)to manufacture deep-drawing *** results are achieved in reducing the stair step effect,which is the main challenge in sheet lamination,by LMD and following post-processing such as milling,ball burnishing,and laser *** new manufacturing route shows that LMD can economically and efficiently reduce the stair step effect and omit the hardening step from the conventional manufacturing process ***,LMD is used to manufacture a hot stamping punch with improved surface roughness by ball burnishing and near-surface complex cooling *** experimental results show that the manufactured punch has lower temperatures during hot stamping compared with the conventionally manufactured *** study shows the successful integration of AM processes with classical forming processes.

关键词： Additive manufacturing Laser metal deposition Selective laser melting Rapid tooling forming tool Layer laminated manufacturing

Microstructure,texture evolution and yield strength symmetry improvement of as-extruded ZK60 Mg alloy via multi-directional impact forging

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 Magnesium and Alloys 2022年第10期10卷 2745-2760页

作者： Chao Cui Wencong Zhang Wenzhen Chen Jian He Xuemin Chen Jiabin Hou School of Materials Science and Engineering Harbin Institute of TechnologyWeihai 264209China Weihai lightweight Materials and forming Engineering Research Center Weihai 264209China Harbin institute of technology-Weihai Innovation Park Weihai 264209China

Multi-direction impact forging(MDIF)was applied to the as-extruded ZK60 Mg alloy,and the microstructure,texture evolution and yield strength symmetry were investigated in the current *** results showed that the average grain size of forged piece was greatly refined to 5.3μm after 120 forging passes,which was ascribed to the segmenting effect of{10–12}twins and the subsequent multiple rounds of dynamic recrystallization(DRX).A great deal of{10–12}twins were activated at the beginning of MDIF process,which played an important role in grain *** forging proceeding,continuous and discontinuous DRX were successively activated,resulting in the fully DRXed ***,the forged piece exhibited a unique four-peak texture,and the initial//ED fiber texture component gradually evolved into multiple texture components composed of//FFD(first forging direction)and//FFD *** special strain path was the key to the formation of the unique four-peak ***{10–12}twinning and basal slip were two dominant factors to the evolution of texture during MDIF *** strengthening and dislocation strengthening were two main strengthening mechanisms of the forged ***,the symmetry of yield strength was greatly improved by MDIF process.

关键词： Multi-directional impact forging Twinning Dynamic recrystallization Texture Yield strength symmetry

Image super‐resolution via dynamic network

在线全文

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence technology 2024年第4期9卷 837-849页

作者： Chunwei Tian Xuanyu Zhang Qi Zhang Mingming Yang Zhaojie Ju School of Software Northwestern Polytechnical UniversityXi'anChina National Engineering Laboratory for Integrated Aero‐Space‐Ground‐Ocean Big Data Application technology Xi'anChina Research&Development institute Northwestern Polytechnical UniversityShenzhenChina School of Economics and Management Harbin Institute of Technology at WeihaiWeihaiChina Tencent AI Lab ShenzhenChina School of Computing University of PortsmouthPortsmouthUK

Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐***,obtained information of these con-volutional neural networks cannot completely express predicted high‐quality images for complex scenes.A dynamic network for image super‐resolution(DSRNet)is presented,which contains a residual enhancement block,wide enhancement block,feature refine-ment block and construction *** residual enhancement block is composed of a residual enhanced architecture to facilitate hierarchical features for image super‐*** enhance robustness of obtained super‐resolution model for complex scenes,a wide enhancement block achieves a dynamic architecture to learn more robust information to enhance applicability of an obtained super‐resolution model for varying *** prevent interference of components in a wide enhancement block,a refine-ment block utilises a stacked architecture to accurately learn obtained ***,a residual learning operation is embedded in the refinement block to prevent long‐term dependency ***,a construction block is responsible for reconstructing high‐quality *** heterogeneous architecture can not only facilitate richer structural information,but also be lightweight,which is suitable for mobile digital *** results show that our method is more competitive in terms of performance,recovering time of image super‐resolution and *** code of DSRNet can be obtained at https://***/hellloxiaotian/DSRNet.

关键词： CNN dynamic network image super‐resolution lightweight network

Soft Sensors for Property‑Controlled Multi‑Stage Press Hardening of 22MnB5

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Automotive Innovation 2023年第3期6卷 352-363页

作者： Juri Martschin Malte Wrobel Joshua Grodotzki Thomas Meurer A.Erman Tekkaya institute of forming technology and lightweight Components TU Dortmund UniversityBaroper Str.30344227 DortmundGermany institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute of Technology(KIT)Hertzstr.1676187 KarlsruheGermany

In multi-stage press hardening,the product properties are determined by the thermo-mechanical history during the sequence of heat treatment and forming *** measure these properties and finally to control them by feedback,two soft sensors are developed in this *** press hardening of 22MnB5 sheet material in a progressive die,where the material is first rapidly austenitized,then pre-cooled,stretch-formed,and finally die bent,serves as the framework for the development of these *** provide feedback on the temporal and spatial temperature distribution,a soft sensor based on a model derived from the Dynamic mode decomposition(DMD)is *** model is extended to a parametric DMD and combined with a Kalman filter to estimate the temperature(-distribution)as a function of all process-relevant control *** soft sensor can estimate the temperature distribution based on local thermocouple measurements with an error of less than 10°C during the process-relevant time *** the online prediction of the final microstructure,an artificial neural network(ANN)-based microstructure soft sensor is *** part of this,a transferable framework for deriving input parameters for the ANN based on the process route in multi-stage press hardening is presented,along with a method for developing a training database using a 1-element model implemented with LS-Dyna and utilizing the material model Mat248(PHS_BMW).The developed ANN-based microstructure soft sensor can predict the final microstructure for specific regions of the formed and hardened sheet in a time span of far less than 1 s with a maximum deviation of a phase fraction of 1.8%to a reference simulation.

关键词： Press hardening Property control Soft sensor Artificial neuronal network Dynamic mode decomposition