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Fault diagnosis of a marine power-generation diesel engine based on the Gramian angular field and a convolutional neural network

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2024年第6期25卷 470-482页

作者： Congyue LI Yihuai HU Jiawei JIANG Dexin CUI Merchant Marine College Shanghai Maritime UniversityShanghai 201306China School of Mechanical and Energy Engineering Shanghai Technical Institute of Electronics&InformationShanghai 201411China

Marine power-generation diesel engines operate in harsh *** vibration signals are highly complex and the feature information exhibits a non-linear *** is difficult to extract effective feature information from the network model,resulting in low fault-diagnosis *** address this problem,we propose a fault-diagnosis method that combines the Gramian angular field(GAF)with a convolutional neural network(CNN).Firstly,the vibration signals are transformed into 2D images by taking advantage of the GAF,which preserves the temporal *** raw signals can be mapped to 2D image features such as texture and *** integrate the feature information,the images of the Gramian angular summation field(GASF)and Gramian angular difference field(GADF)are fused by the weighted average fusion ***,the channel attention mechanism and temporal attention mechanism are introduced in the CNN model to optimize the CNN learning *** the concept of residuals in the attention mechanism improves the feasibility of ***,the weighted average fused images are fed into the CNN for feature extraction and fault *** validity of the proposed method is verified by experiments with abnormal valve *** average diagnostic accuracy is 98.40%.When−20 dB≤signal-to-noise ratio(SNR)≤20 dB,the diagnostic accuracy of the proposed method is higher than 94.00%.The proposed method has superior diagnostic ***,it has a certain anti-noise capability and variable-load adaptive capability.

关键词： Multi-attention mechanisms(MAM) Convolutional neural network(CNN) Gramian angular field(GAF) Image fusion Marine power-generation diesel engine Fault diagnosis

Relational Turkish Text Classification Using Distant Supervised Entities and Relations

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Computers, Materials & Continua 2024年第5期79卷 2209-2228页

作者： Halil Ibrahim Okur Kadir Tohma Ahmet Sertbas Department of Computer Engineering Faculty of Engineering and Natural SciencesIskenderun Technical UniversityHatay31200Turkey Department of Computer Engineering Faculty of EngineeringIstanbul University-CerrahpasaIstanbul34310Turkey

Text classification,by automatically categorizing texts,is one of the foundational elements of natural language processing *** study investigates how text classification performance can be improved through the integration of entity-relation information obtained from the Wikidata(Wikipedia database)database and BERTbased pre-trained Named Entity Recognition(NER)*** on a significant challenge in the field of natural language processing(NLP),the research evaluates the potential of using entity and relational information to extract deeper meaning from *** adopted methodology encompasses a comprehensive approach that includes text preprocessing,entity detection,and the integration of relational *** conducted on text datasets in both Turkish and English assess the performance of various classification algorithms,such as Support Vector Machine,Logistic Regression,Deep Neural Network,and Convolutional Neural *** results indicate that the integration of entity-relation information can significantly enhance algorithmperformance in text classification tasks and offer new perspectives for information extraction and semantic analysis in NLP *** of this work include the utilization of distant supervised entity-relation information in Turkish text classification,the development of a Turkish relational text classification approach,and the creation of a relational *** demonstrating potential performance improvements through the integration of distant supervised entity-relation information into Turkish text classification,this research aims to support the effectiveness of text-based artificial intelligence(AI)***,it makes significant contributions to the development ofmultilingual text classification systems by adding deeper meaning to text content,thereby providing a valuable addition to current NLP studies and setting an important reference point for future research.

关键词： Text classification relation extraction NER distant supervision deep learning machine learning

Numerical study of convective heat transfer in static arrangements of particles with arbitrary shapes:A monolithic hybrid lattice Boltzmann-finite difference-phase field solver

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Particuology 2024年第2期85卷 186-197页

作者： Reza Namdar Mohammadhassan Khodsiani Hesameddin Safari Tanya Neeraj Seyed Ali Hosseini Frank Beyrau Benoit Fond Dominique Thevenin Fathollah Varnik Interdisciplinary Centre for Advanced Materials Simulation(ICAMS) Ruhr-University BochumBochum44801Germany Laboratory of technical Thermodynamics University of Magdeburg"Otto von Guericke"Magdeburg39106Germany Laboratory of Fluid Dynamics and technical Flows University of Magdeburg"Otto von Guericke"MagdeburgD-39106Germany Department of Mechanical and Process Engineering ETH ZurichZurich8092Switzerland ONERA The French Aerospace Lab Department of AerodynamicsAeroelasticity and Acoustics(DAAA)Paris-Saclay UniversityMeudon92190France

A compressible lattice Boltzmann-finite difference method is extended by the phase-field approach into a monolithic scheme to study fluid flow and heat transfer through regular arrangements of solid bodies of circular,elliptical and irregular *** advantage of using the phase-field method is demon-strated both in its simplicity of accounting for flow and thermal boundary conditions at solid surfaces with irregular shapes and in the capability of generating such complex-shaped *** an array of discs,numerical results for the overall solid-to-gas heat transfer rate are validated via experiments on flow through arrays of hot *** thus validated compressible LB-FD-PF hybrid scheme is used to study the dependence of heat transfer on flow and thermal boundary conditions(Reynolds number,temperature difference between the hot solid bodies and the inlet gas),porosity as well as on the shape of solid *** are rationalized in terms of the residence time of the gas close to the solid body and downstream variations of gas velocity and *** for further applications of the proposed methodology are also discussed.

关键词： Lattice Boltzmann method Finite difference scheme Convective heat transfer Diffuse interface Thermal compressible flow

Magnesium oxide(MgO)nanoadsorbents in wastewater treatment:A comprehensive review

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Journal of Magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： H.C.S.Perera V.Gurunanthanan Anoop Singh M.M.M.G.P.G.Mantilaka G.Das Sandeep Arya Department of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of Science University of PeradeniyaPeradeniyaSri Lanka Department of Humanities and Sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India Centre for Global Health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Department of Physics University of JammuJammu and Kashmir180006India

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge,necessitating effective and sustainable separation *** review article provides a detailed examination of magnesium oxide(MgO)nanoparticles as an innovative nanoadsorbent for wastewater treatment,with a specific focus on heavy metal and dye *** review comprehensively explores various aspects of MgO nanoparticles,including their structural characteristics and synthesis *** article delves into the morphology and crystallographic arrangement of MgO nanoparticles,offering insights into their structural *** the complexity of adsorption processes,the review identifies and analyzes parameters influencing the adsorption efficiency of MgO nanoparticles,such as temperature,pH,contact time,initial concentration,and co-existing *** interplay between these parameters and the adsorption capability of MgO nanoparticles emphasizes the importance of optimizing operational ***,the review assesses various synthesis methods for MgO nanoparticles,including sol-gel,hydrothermal,precipitation,green synthesis,solvothermal,and template-assisted *** discusses the advantages,limitations,and resulting nanoparticle characteristics of each method,enabling readers to grasp the implications of synthesis processes on adsorption *** comprehensive review consolidates current insights into the effectiveness of MgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to MgO ***,there is a need to investigate the use of MgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： MgO nanoparticles Nanoadsorbent Wastewater treatment Heavy metals Dye separation Adsorption Synthesis methods

Investigating and predicting the role of photovoltaic, wind, and hydrogen energies in sustainable global energy evolution

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Global Energy Interconnection 2024年第4期7卷 429-445页

作者： Mahmood Swadi Dheyaa Jasim Kadhim Mohamed Salem Firas Mohammed Tuaimah Ammar SabriMajeed Ali Jawad Alrubaie Department of Electrical Engineering College of EngineeringUniversity of BaghdadBaghdad 10001Iraq Libyan Authority for Scientific Research Tripoli 80045Libya School of Electrical and Electronic Engineering Universiti Sains Malaysia(USM)Nibong Tebal 14300PenangMalaysia Continuing Education Center University of BaghdadBaghdad 10001Iraq Al-Furat Al-Awsat technical university AL-Mussaib Technical CollegeBabylonIraq

The global shift toward next-generation energy systems is propelled by the urgent need to combat climate change and the dwindling supply of fossil *** review explores the intricate challenges and opportunities for transitioning to sustainable renewable energy sources such as solar,wind,and *** transition economically challenges traditional energy sectors while fostering new industries,promoting job growth,and sustainable economic *** transition to renewable energy demands social equity,ensuring universal access to affordable energy,and considering community *** environmental benefits include a significant reduction in greenhouse gas emissions and a lesser ecological *** study highlights the rapid growth of the global wind power market,which is projected to increase from$112.23 billion in 2022 to$278.43 billion by 2030,with a compound annual growth rate of 13.67%.In addition,the demand for hydrogen is expected to increase,significantly impacting the market with potential cost reductions and making it a critical renewable energy source owing to its affordability and zero *** 2028,renewables are predicted to account for 42%of global electricity generation,with significant contributions from wind and solar photovoltaic(PV)technology,particularly in China,the European Union,the United States,and *** developments signify a global commitment to diversifying energy sources,reducing emissions,and moving toward cleaner and more sustainable energy *** review offers stakeholders the insights required to smoothly transition to sustainable energy,setting the stage for a resilient future.

关键词： Next energy Renewable energy Sustainability Environmental benefits Economic opportunities

Microstructure and thermal properties of dissimilar M300–CuCr1Zr alloys by multi-material laser-based powder bed fusion

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 118-128页

作者： Xiaoshuang Li Dmitry Sukhomlinov Zaiqing Que Aerosint SA B-4040 HerstalBelgium Aalto university Department of Chemical and Metallurgical EngineeringEspoo 02150Finland VTT technical Research Centre of Finland Espoo 02044Finland

Multi-material laser-based powder bed fusion (PBF-LB) allows manufacturing of parts with 3-dimensional gradient and additional functionality in a single step. This research focuses on the combination of thermally-conductive CuCr1Zr with hard M300 tool *** interface configurations of M300 on CuCr1Zr and CuCr1Zr on M300 were investigated. Ultra-fine grains form at the interface due to the low mutual solubility of Cu and steel. The material mixing zone size is dependent on the configurations and tunable in the range of0.1–0.3 mm by introducing a separate set of parameters for the interface layers. Microcracks and pores mainly occur in the transition *** of these defects, the thermal diffusivity of bimetallic parts with 50vol% of CuCr1Zr significantly increases by 70%–150%compared to pure M300. The thermal diffusivity of CuCr1Zr and the hardness of M300 steel can be enhanced simultaneously by applying the aging heat treatment.

关键词： multi-material additive manufacturing laser-based powder bed fusion thermal diffusivity dissimilar metals copper alloy

Analyze the Performance of Electroactive Anticorrosion Coating of Medical Magnesium Alloy Using Deep Learning

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Computers, Materials & Continua 2024年第4期79卷 263-278页

作者： Yashan Feng Yafang Tian Yongxin Yang Yufang Zhang Haiwei Guo Jing’an Li Advanced Functional Materials Laboratory Zhengzhou Railway Vocational and Technical CollegeZhengzhou450000China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou450000China

Electroactive anticorrosion coatings are specialized surface treatments that prevent or minimize corrosion. Thestudy employs strategic thermodynamic equilibriumcalculations to pioneer a novel factor in corrosion protection.A first-time proposal, the total acidity (TA) potential of the hydrogen (pH) concept significantly shapes medicalmagnesium alloys. These coatings are meticulously designed for robust corrosion resistance, blending theoreticalinsights and practical applications to enhance our grasp of corrosion prevention mechanisms and establisha systematic approach to coating design. The groundbreaking significance of this study lies in its innovativeintegration of the TA/pH concept,which encompasses the TA/pH ratio of the chemical environment. This approachsurpasses convention by acknowledging the intricate interplay between the acidity and pH levels within thecoating formulation, thereby optimizing metal-phosphate-based conversion coatings and transforming corrosionmitigation strategies. To authenticate the TA/pH concept, the study comprehensively compares its findings withexisting research, rigorously validating the theoretical framework and reinforcing the correlates among TA/pHvalues and observed corrosion resistance in the coatings. The influence of mutations that occur naturally inthe detergent solution on persistent phosphorus changes is shown by empirical confirmation, which improvescorrosion resistance. This realization advances the field ofmaterials and the field’s knowledge of coated generation,particularly anticorrosion converter layers.

关键词： Medical magnesium alloys hydrogen gas anticorrosion total acidity potential of the hydrogen(pH)

Anisotropic spin transport and photoresponse characteristics detected by tip movement in magnetic single-molecule junction

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Chinese Physics B 2024年第4期33卷 640-648页

作者：陈登辉羊志付新宇秦申奥严岩王传奎李宗良邱帅 Shandong Key Laboratory of Medical Physics and Image Processing&Shandong Provincial Engineering and technical Center of Light Manipulations School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule ***,using the first-principles method,we theoretically investigate spin transport properties and photoresponse characteristics in trimesic acid magnetic single-molecule junctions with different molecular adsorption orientations and electrode contact *** transport calculations indicate that a single-molecule switch and a significant enhancement of spin transport and photoresponse can be achieved when the molecular adsorption orientation changes from planar geometry to upright *** maximum spin polarization of current and photocurrent in upright molecular junctions exceeds 90%.Moreover,as the Ni tip electrode moves,the tunneling magnetoresistance of upright molecular junctions can be increased to 70%.The analysis of the spin-dependent PDOS elucidates that the spinterfaces between organic molecule and ferromagnetic electrodes are modulated by molecular adsorption orientation,where the molecule in upright molecular junctions yields higher spin *** theoretical work paves the way for designing spintronic devices and optoelectronic devices with anisotropic functionality base on anisotropic molecules.

关键词： molecular spintronics spin polarization tunneling magnetoresistance photocurrent single-molecule junctions

A regular MOG black hole's impact on shadows and gravitational weak lensing in the presence of a quintessence field

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Communications in Theoretical Physics 2024年第8期76卷 93-104页

作者： Ahmad Al-Badawi Sanjar Shaymatov Mirzabek Alloqulov Anzhong Wang Department of Physics Al-Hussein Bin Talal University Institute for Theoretical Physics and Cosmology Zhejiang University of Technology Tashkent State technical university university of Tashkent for Applied Sciences New Uzbekistan university Institute of Fundamental and Applied Research National Research University TIIAME GCAP-CASPER Physics Department Baylor University

We investigate the impact of the modified gravity（MOG） field and the quintessence scalar field on horizon evolution, black hole（BH） shadow and the weak gravitational lensing around a static spherically symmetric BH. We first begin to write the BH metric associated with the MOG parameter and quintessence scalar field. We then determine the BH shadow and obtain numerical solutions for the photon sphere and shadow radius. We show that the MOG（α） and the quintessence（c） parameters have a significant impact on the BH shadow and photon *** on the analysis, we further show that the combined effects of the MOG parameter and quintessence field can increase the values of BH shadow and photon sphere radii. We also obtain constraints on the BH parameters by applying the observational data of Sgr A★and M87★.Finally, we consider the weak deflection angle of BH within the context of the Gauss–Bonnet theorem（GBT） and show that the combined effects of the MOG and quintessence parameters do make the value of the deflection angle increase, and find this remarkable property is in good agreement with the physical meaning of both parameters that can maintain the strong gravitational field in the surrounding environment of a BH.

关键词： gravitational weak lensing modified gravity quintessence field shadows