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HWD-YOlO: A New Vision-Based Helmet Wearing Detection Method

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Computers, Materials and Continua 2024年第3期80卷 4543-4560页

作者： Sun l. li H. Wang l. College of Information Science and Technology Beijing University of Technology Beijing 100124 China Chinese Institute of Coal Science Beijing 100013 China State Key laboratory for Intelligent Coal Mining and Strata Control Beijing 100013 China Engineering Research Center of Digital Community of Ministry of Education Beijing 100124 China

It is crucial to ensure workers wear safety helmets when working at a workplace with a high risk of safety accidents, such as construction sites and mine tunnels. Although existing methods can achieve helmet detection in images, their accuracy and speed still need improvements since complex, cluttered, and large-scale scenes of real workplaces cause server occlusion, illumination change, scale variation, and perspective distortion. So, a new safety helmet-wearing detection method based on deep learning is proposed. Firstly, a new multi-scale contextual aggregation module is proposed to aggregate multi-scale feature information globally and highlight the details of concerned objects in the backbone part of the deep neural network. Secondly, a new detection block combining the dilate convolution and attention mechanism is proposed and introduced into the prediction part. This block can effectively extract deep features while retaining information on fine-grained details, such as edges and small objects. Moreover, some newly emerged modules are incorporated into the proposed network to improve safety helmet-wearing detection performance further. Extensive experiments on open dataset validate the proposed method. It reaches better performance on helmet-wearing detection and even outperforms the state-of-the-art method. To be more specific, the mAP increases by 3.4%, and the speed increases from 17 to 33 fps in comparison with the baseline, You Only look Once (YOlO) version 5X, and the mean average precision increases by 1.0% and the speed increases by 7 fps in comparison with the YOlO version 7. The generalization ability and portability experiment results show that the proposed improvements could serve as a springboard for deep neural network design to improve object detection performance in complex scenarios. Copyright © 2024 The Authors. Published by Tech Science Press.

关键词： attention mechanism deep learning feature extraction Object detection safety helmet wearing detection

Special Properties of Morita Contexts

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Algebra Colloquium 2024年第2期31卷 309-322页

作者： Kamal Paykan l.A.Bokut Department of Mathematics Tafresh UniversityTafreshIran 不详

In this paper we continue the study of various ring theoretic properties of Morita *** and sufficient conditions are obtained for a general Morita context or a trivial Morita context or a formal triangular matrix ring to satisfy a certain ring property which is among being Kasch,completely primary,quasi-duo,2-primal,NI,semiprimitive,projective-free,*** also characterize when a general Morita context is weakly principally quasi-Baer or strongly right mininjective.

关键词： Morita context formal triangular matrix ring Kasch quasi-duo Köthe's conjecture weakly principally quasi-Baer

Cognition and movement in neurodegenerative disorders:a dynamic duo

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Neural Regeneration Research 2024年第10期19卷 2101-2102页

作者： Marit F.l.Ruitenberg Department of Health Medical and NeuropsychologyLeiden UniversityLeidenthe Netherlands leiden Institute for Brain and Cognition Leidenthe Netherlands

People with neurodegenerative disorders often experience problems across a variety of functional domains,including cognition,movement,and psychosocial *** classification of these disorders is based on the phenotypical manifestations that represent the most prominent clinical *** example,Parkinson's disease and Huntington's disease are typically regarded as movement disorders,whereas Alzheimer's disease(AD) and other dementias are regarded as cognitive disorders.

关键词： disorders Huntington degenerative

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Phase-field lattice Boltzmann model for dendrites growing and moving in melt flow

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npj Computational Materials 2019年第1期5卷 140-149页

作者： lászlóRátkai Tamás Pusztai lászlóGránásy Wigner Research Centre for Physics P.O.Box 49H-1525 BudapestHungary Brunel Centre of Advanced Solidification Technology Brunel UniversityUxbridgeMiddlesex UB83PHUK

The phase-field and lattice Boltzmann methods have been combined to simulate the growth of solid particles moving in melt *** handle mobile particles,an overlapping multigrid scheme was developed,in which each individual particle has its own moving grid,with local fields attached to *** this approach we were able to simulate simultaneous binary solidification,solute diffusion,melt flow,solid motion,the effect of gravity,and collision of the *** method has been applied for describing two possible modes of columnar to equiaxed transition in the Al–Ti system.

关键词： solidification moving lattice

Generation of millijoule-level sub-5 fs violet laser pulses

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High Power laser Science and Engineering 2024年第2期12卷 33-40页

作者： Xinhua Xie Yi Hung Yunpei Deng Adrian l.Cavalieri Andrius Baltuška Steven l.Johnson SwissFEl Paul Scherrer InstituteVilligen PSISwitzerland Photonics Institute Technische Universität WienViennaAustria Institute of Applied Physics University of BernBernSwitzerland Institute for Quantum Electronics Physics DepartmentETH ZurichZurichSwitzerland

We demonstrate the generation,spectral broadening and post-compression of second harmonic pulses using a thin beta barium borate(BBO)crystal on a fused-silica substrate as the nonlinear interaction *** combining second harmonic generation in the BBO crystal with self-phase modulation in the fused-silica substrate,we efficiently generate millijoule-level broadband violet pulses from a single optical *** second harmonic spectrum covers a range from long wave ultraviolet(down to 310 nm)to visible(up to 550 nm)with a bandwidth of 65 ***,we compress the second harmonic beam to a duration of 4.8 fs with a pulse energy of 0.64 mJ(5 fs with a pulse energy of 1.05 mJ)using chirped *** all-solid free-space apparatus is compact,robust and pulse energy scalable,making it highly advantageous for generating intense second harmonic pulses from near-infrared femtosecond lasers in the sub-5 fs regime.

关键词： post-compression second harmonic generation self-phase modulation supercontinuum generation

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On the neutrality of two symmetric TSP solvers toward instance specification

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Science China(Information Sciences) 2019年第11期62卷 198-200页

作者： Gloria Cerasela CRI?AN lászló Barna IANTOVICS lászló KOVáCS Faculty of Sciences Vasile Alecsandri University Faculty of Sciences and letters University of MedicinePharmacy Sciences and Technology Faculty of Mechanical Engineering and Informatics University of Miskolc

Dear editor,Currently, many computationally difficult problems can be solved using very efficient *** of these state-of-the-art methods have online implementations. The research question addressed herein is how sensit... 详细信息

关键词： On the neutrality of two symmetric TSP solvers toward instance specification

Complex-frequency waves:beat loss and win sensitivity

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light(Science & Applications) 2024年第2期13卷 181-183页

作者： Qingqing Cheng Tao l School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Respiratory Diseases and Critical Medicine Quzhou Hospital Affiliated to Wenzhou Medical UniversityQuzhou324000China National laboratory of Solid State Microstructures College of Engineering and Applied SciencesNanjing UniversityNanjing210093China

Recent experiments have demonstrated that synthesized complex-frequency waves can impart a virtual gain to molecule sensing systems,which can effectively restore information lost due to intrinsic molecular *** enhancement notably amplifies the signal of trace molecular vibrational fingerprints,thereby substantially improving the upper limit of sensitivity.

关键词： thereby Complex limit

Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： Chaofeng lü Chao Sun Shengqiang Cai Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science laboratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are generally relevant to stellar evolution,geophysical movement,astrophysical flows,and *** also frequently occur in various engineering scenarios involving acceleration,such as the launch of space shuttles,operation of rotor engines,impacts and explosions,chemical separation processes,and overloaded testing *** is already demonstrated in physiological experiments that living organisms of animals or plants could be damaged,either temporarily or permanently,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal equipment or rapidly rotating devices are omnipresent in various fields,such as aerospace engineering,geophysical science,chemical and biomedical engineering,nuclear engineering,rotating flows,and physical modeling tests.

关键词： geophysical Earth stellar

Corrosion testing of X52 and X80 steels immersed in stimulated emulsions using a real petroleum sample

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Petroleum Research 2024年第2期9卷 304-316页

作者： l.M.Quej-Ake J.l.Alamilla A.Contreras Instituto Mexicano del Petróleo Eje Central Lázaro CárdenasNorte 152San Bartolo AtepehuacanGustavo A.MaderoCiudad de MéxicoC.P.07730México

The aim of this study is to evaluate the internal corrosion process on X52 and X80 steels/real petroleum interfaces containing condensed hydrocarbon plus oilfield-produced water,which were subjected to stimulated emulsions using 50/50 vol ratio mixtures at 45℃,different hydrodynamic conditions,1 h,and 24 h.A washing process by using deionized water was proposed to simulate and identify the corrosiveness of the hydrocarbon phase after 24 h of exposure *** characterization by electrochemical impedance spectroscopy and the monitoring of the polarization curves indicated that X80 steel/oilfield-produced water interfaces were more susceptible to corrosion than X52 steel exposed to oilfield-produced *** combined speed rotation of 600 rpm using a magnetic stirrer+600 rpm using a rotating disk electrode decreased the corrosion rate on X52 *** stimulated emulsions made of hydrocarbon+oilfield-produced water and hydrocarbon+deionized water at 24 h increased the corrosion rate on X80 steel(0.34 mm/year and 0.43 mm/year,respectively),promoting the formation of erosion and pitting *** types of corrosion depended mainly on the physicochemical properties of the hydrocarbon,oilfield-produced water,exposure times,and hydrodynamic systems in which the hydrocarbon was studied.

关键词： Corrosion Emulsions X52 steel X80 steel