检索结果-南通市图书馆

Optimised CNN Architectures for Handwritten Arabic Character Recognition

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第6期79卷 4905-4924页

作者： Salah Alghyaline department of Computer Science TheWorld Islamic Sciences and Education UniversityAmman1101-11947Jordan

Handwritten character recognition is considered challenging compared with machine-printed characters due to the different human writing *** is morphologically rich,and its characters have a high *** Arabic language includes 28 *** character has up to four shapes according to its location in the word(at the beginning,middle,end,and isolated).This paper proposed 12 CNN architectures for recognizing handwritten Arabic *** proposed architectures were derived from the popular CNN architectures,such as VGG,ResNet,and Inception,to make them applicable to recognizing character-size *** experimental results on three well-known datasets showed that the proposed architectures significantly enhanced the recognition rate compared to the baseline *** experiments showed that data augmentation improved the models’accuracies on all tested *** proposed model outperformed most of the existing *** best achieved results were 93.05%,98.30%,and 96.88%on the HIJJA,AHCD,and AIA9K datasets.

关键词： Optical character recognition(OCR) handwritten arabic characters deep learning

Effects of the inlet particle spatial distribution on the performance of a gas-solid cyclone separator

维普期刊数据库评论

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 133-145页

作者： Yuge Yao Manxia Shang Xiwei Ke Zhong Huang Tuo Zhou Junfu Lyu Key Laboratory for Thermal Science and Power Engineering of Ministry of education Department of Energy and Power EngineeringTsinghua UniversityBeijing100084China

The present study was aimed at the inlet particle spatial distribution of a gas-solid separator with high solid loading and investigated its effects on cyclone performance and the inner flow *** flow fields of a cyclone with different rectangular particle flow areas on the inlet surface were numerically simulated using a four-way coupling *** simulated results indicate that reducing the inlet particle flow area and lowing the inlet particle position can effectively reduce the scattered particles inside the cyclone separator and enhance the separation *** gathering the particles to the centerline can also weaken the particle *** particles near the roof account for the swirling particle ceiling *** inlet particle spatial distribution affects the pressure drop mainly by affecting the gas tangential velocity in the cylinder ***,compared to the hori-zontal particle distribution on the inlet surface,the vertical particle distribution has greater effects on cyclone performance.

关键词： Gas-solid cyclone Inlet particle spatial distribution Four-way coupling Separation efficiency Scattered particle

Thermal Decomposition and Oxidative Decomposition Mechanism of HFC-134a by Experimental and DFT Method

维普期刊数据库评论

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 Thermal Science 2024年第5期33卷 1990-2003页

作者： XU Yunting ZHANG Kai DAI Xiaoye SHI Lin Key Laboratory for Thermal Science and Power Engineering of Ministry of education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China

In response to the Kigali Amendment to the Montreal Protocol and global low-carbon emission environmental requirements,the phase-out and decomposition of numerous HFC refrigerants have become urgent,necessitating efficient and mild decomposition *** study investigates the thermal decomposition and oxidative thermal decomposition pathways of the typical hydrofluorocarbon refrigerant HFC-134a,employing a combination of experimental and quantum chemical DFT simulation *** chemical simulations reveal that the initial reaction bond cleavage serves as the rate-determining step during the thermal decomposition process,with the most easily detectable closed-shell products including CF_(2)=CHF,HF,CH_(3)F,CHF_(3),CH_(2)F_(2),and CF_(4).Reactive oxygen species can significantly reduce the Gibbs free energy barrier for HFC-134a *** achieve efficient degradation of HFC-134a,appropriate catalysts should be developed and selected to increase the level of reactive oxygen species in the reaction *** studies further corroborate that HFC-134a may undergo degradation through distinct reaction pathways under varying temperature(240℃to360℃)and pressure(0.1 MPa to 4.5 MPa)conditions,in agreement with simulation predictions.

关键词： HFC-134a pyrolysis oxidative thermal decomposition DFT refrigerant

Improved YOLOv5 foreign object detection for transmission lines

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2024年第8期20卷 490-496页

作者： ZHOU Liming LI Shixin ZHU Zhiren CHEN Fankai LIU Chen DONG Xiuhuan Electrical Engineering department Tianjin University of Technology and EducationTianjin 300222China

The traditional transmission line detection has the problems of low *** improve the performance,this paper proposes an improved you only look once version 5(YOLOv5)transmission line foreign object detection ***,efficient channel attention(ECA)module is introduced in the backbone network for focusing the target features and improving the feature extraction capability of the ***,bilinear interpolation upsampling is introduced in the neck network to improve the model detection ***,by integrating the efficient intersection over union(EIoU)loss function and Soft non-maximum suppression(Soft NMS)algorithm,the convergence speed of the model is accelerated while the detection effect of the model is *** to the original algorithm,the improved algorithm reduces the number of parameters by 16.4%,increases the mean average precision(mAP)@0.5 by 3.9%,mAP@0.5:0.95 by 6.3%,and increases the detection speed to 55.3 frames per second(FPS).The improved algorithm is able to improve the performance of the foreign object detection in transmission lines effectively.

关键词： network algorithm union

Generation and Suppression of Pendant Droplet Oscillation in Electron Beam Directed Energy Deposition

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第6期37卷 215-229页

作者： Zhiyue Liang Zhenyu Liao Haoyu Zhang Zixiang Li Li Wang Baohua Chang Dong Du department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationTsinghua UniversityBeijing 100084China

Electron beam–directed energy deposition(EB–DED)has emerged as a promising wire-based metal additive manufacturing ***,the effects of EBs on pendant droplets at wire tips have not yet been *** aim of this study is to enhance the understanding of this action by analyzing the mechanism of droplet *** pendant droplet oscillation phenomenon hinders the stable transfer of droplets to the molten pool and limits the feasibility of manufacturing complex lattice structures by EB–***,another aim of this study is to create an oscillation suppression *** escalating asymmetric amplitude is the main characteristic of droplet *** primary oscillationinducing force is the recoil force generated from the EB-acted local surface of the *** physical mechanism of this force is the rapid increase and uneven distribution of the local surface temperature caused by the partial action of the *** prerequisites for droplet oscillation include vacuum conditions,high power densities,and bypass wire feeding *** proposed EB–dynamic surrounding melting(DSM)method can be applied to conveniently and effectively suppress oscillations,enable the accurate transfer of droplets to the molten pool,and achieve stable processes for preparing the strut elements of lattice *** the temperature and improving the uniformity of its distribution are the mechanisms of oscillation suppression in EB–*** this study,the physical basis for interpreting the mechanism by which EBs act on droplets and the technical basis for using EB–DED to prepare complex lattice structure parts are provided.

关键词： Additive manufacturing Electron beam freeform fabrication In situ monitoring Pendant droplet

Effect of Humidity on Formaldehyde Oxidation over Ce_(0.8)Zr_(0.2)O_(y)Catalyst

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan university of Technology(Materials Science) 2024年第5期39卷 1108-1115页

作者： TANG Ruijiu YANG Zonglin LIU Xiang JIA Lijuan WANG Fang DUAN Kaijiao LIU Tiancheng College of Chemistry and Environment Yunnan Minzu UniversityTechnology Innovation Team of Green Purification Technology for Industrial Waste GasEducation Department of YunnanKey Laboratory of Environmental Functional Materials of Yunnan Province Education DepartmentKunming 650504China

In the preparation of a series of Ce_(0.8)Zr_(0.2)O_(y)catalysts catalyzing the removal of formaldehyde,BET,H2-TPR,IR,SEM,XPS,and XRD were used to characterize the catalyst,and the influence of humidity on the catalyst activity was studied by adjusting the humidity during the *** experimental results showed that the formaldehyde removal rate increased with the increase of *** the humidity was higher than 50%,the formaldehyde removal rate decreased by 3%over that when the humidity was 50%.The characterization results showed that humidity facilitated the activation of oxygen and the formation of hydroxyl groups,which both promoted the formation and oxidative decomposition of intermediates and prevented the deposition of intermediates that clogged the pores,allowing more formaldehyde to be adsorbed and oxidized,which increased the activity of the *** provides new mechanistic evidence for the oxidation of formaldehyde and helps in the development of relatively low-cost materials for formaldehyde purification.

关键词： formaldehyde humidity Ce_(0.8)Zr_(0.2)O_(y) catalytic oxidation

Key factors to prioritize when preparing for the Olympic Games

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第6期13卷 719-721页

作者： George P.Nassis Gregoire P.Millet department of Physical education College of EducationUnited Arab Emirates UniversityAl Ain 15551United Arab Emirates Institute of Sport Sciences University of LausanneLausanne 1015Switzerland

We need more research that will fulfill the needs of athletes and *** is a common statement,highly relevant nowadays only a few weeks before the commencement of the Paris 2024 Olympic *** fill this gap,we have identified 6 topics that we feel coaches and athletes would be interested in learning more to optimize their preparation for the *** topics are.

关键词： preparing statement interested

Dynamics of a rotating ring-stiffened sandwich conical shell with an auxetic honeycomb core

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 963-982页

作者： S.JAHANGIRI A.GHORBANPOUR ARANI Z.KHODDAMI MARAGHI department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan ***Iran Faculty of Engineering Mahallat Institute of Higher EducationMahallat ***Iran

The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is *** shell is modeled utilizing the first-order shear deformation theory(FSDT)incorporating the relative,centripetal,and Coriolis accelerations alongside the initial hoop tension created by the *** governing equations,compatibility conditions,and boundary conditions are attained using Hamilton’s *** trigonometric functions,an analytical solution is derived in the circumferential direction,and a numerical one is presented in the meridional direction via the differential quadrature method(DQM).The effects of various factors on the critical rotational speeds and forward and backward frequencies of the shell are *** present work is the first theoretical work regarding the dynamic analysis of a rotating sandwich conical shell with an auxetic honeycomb core strengthened with a ring support.

关键词： free vibration conical shell rotating shell ring support auxetic honeycomb

Embodying Deeply Held Values in education:Seeking a More Equitable World for Both Humans and Non-Humans

在线全文

学校读者我要写书评

暂无评论

ECNU Review of education 2024年第2期7卷 241-251页

作者：林静 Shue-kei Joanna Mok Virginia Gomes department of Counseling Higher Education and Special EducationCollege of Education3214 Benjamin BuildingUniversity of MarylandCollege ParkMD20742USA

Highlights In this article,we contend that the bedrock of an equitable world lies in the profound recognition of love as the fundamental force permeating the *** believe that love is built into the essence of who we *** posit that genuine progress toward an equitable world is elusive unless we place love,both for one another and for the natural world,at the core of our educational endeavors.

关键词： Embodied practices heart and spirit love and equity love as a cosmic force