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Applied mathematics and mechanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHmAN m.TURKYILmAzOGLU z.mUSHTAQ Department of mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c mATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,m=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

Transient Characteristics and Accommodative Current Limiting Strategy for Bidirectional Interlinking Converters in Hybrid AC/DC microgrids

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1575-1588页

作者： Xia shen zhikang Shuai Wen Huang Chao shen Yang shen z.John shen College of Electrical and Information Engineering Hunan UniversityChangsha 410082China Department of Electrical and Computer Engineering Illinois Institute of TechnologyChicagoIL 60616 USA

Bidirectional interlinking converter(BIC)is the core equipment in a hybrid AC/DC microgrid connected between AC and DC ***,the variety of control modes and flexible bidirectional power flow complicate the influence of AC faults on BIC itself and on DC sub-grid,which potentially threaten both converter safety and system *** study first investigates AC fault influence on the BIC and DC bus voltage under different BIC control modes and different pre-fault operation states,by developing a mathematical model and equivalent sequence ***,based on the analysis results,a general accommodative current limiting strategy is proposed for BIC without limitations to specific mode or operation *** amplitude is predicted and constrained according to the critical requirements to protect the BIC and relieving the AC fault influence on the DC bus *** with conventional methods,potential current limit failure and distortions under asymmetric faults can also be ***,experiments verify feasibility of the proposed method.

关键词： Bidirectional interlinking converter current limiting fault characteristic hybrid AC/DC microgrid variation/oscillation of DC bus voltage

CFD investigation of structural effects of internal gas intake on powder conveying performance in fuel supply systems for aerospace engines

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Particuology 2024年第9期92卷 140-154页

作者： Guanlong Ren Haijun Sun Fangjun chen Wen shen Yunzhen Cai Yihua Xu Henrik Ström Bilainu Oboirien Qingang Xiong School of Aircraft Engineering Nanchang Hangkong UniversityNanchang330063China Engineering Research Center of Aero-engine Technology for General Aviation Ministry of EducationNanchang330063China State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhou510640China Department of mechanics and maritime Sciences Chalmers University of TechnologyGöteborg41296Sweden Department of Chemical Engineering University of JohannesburgJohannesburg17011South Africa

Optimal design of gas intake in powder fuel supply systems is crucial for performance of aerospace *** is little research on the impact of intake structure on powder conveying *** novel internal intakes were proposed,which are spherical,cube-shaped,and *** validation,CFD simulations demonstrate that fluctuation of mass flow rate of powders in the dome-shaped intake is reduced by about 73.3%compared with the annular external *** trends of phase velocities are similar for the spherical and cube-shaped intakes,while those are similar for the annular external and dome-shaped internal *** of area of gas zone for the annular external and spherical internal intakes is larger than that for the cube-shaped and dome-shaped internal *** and relative pressure drop in the fluidization chamber have a stable stage,and fluctuation of relative pressure drop is small when dome-shaped internal intake is used.

关键词： Powder supply system Intake structure Dense gas-solid flow Two-fluid model Powder fluidization Pressure drop

Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser Science and Engineering 2024年第3期12卷 62-68页

作者： L.R.Yin X.F.Li Y.J.Gu N.Cao Q.Kong m.Büscher S.m.Weng m.chen.z.m.shen. Key Laboratory of Nuclear Physics and Ion-beam Application(moE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SANKEN(Institute of Scientific and Industrial Research) Osaka UniversityOsakaJapan Sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(moE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

Stability Investigation and Improvement for DC Cascade Systems with Simplified Impedance-based Stability Criterion

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1044-1052页

作者： Junbin Fang zhikang Shuai Yang Li zhibing Wang Xiangyang Wu Xia shen z.John shen College of Electrical and Information Engineering Hunan UniversityChangsha 410082China Renewable Energy Department of China Electric Power Research Institute Beijing 100192China Department of Electrical and Computer Engineering Illinois Institute of TechnologyChicagoIL 60616USA IEEE

In DC distributed power systems(DPSs),the complex impedance interactions possibly lead to DC bus voltage oscillation or *** previous research,the stability analysis of DPSs is implemented based on mathematical analysis in control *** specific mechanisms of the instability of the cascade system have not been intuitively *** this paper,the stability analysis of DPSs based on the traditional Nyquist criterion is simplified to the resonance analysis of the seriesconnected port impedance(z=R+jX)of source and load *** reveals that the essential reason for impedance instability of a DC cascade system is that the negative damping characteristic(Rmpedance amplifies the internal resonance source at reactance zero-crossing *** simplified stability criterion for DC cascade systems can be concluded as:in the negative damping frequency ranges(Rzero-crossing point of the reactance component(i.e.,X=0).According to the proposed stability criterion,the oscillation modes of cascade systems are classified.A typical one is the internal impedance instability excited by the negative damping,and the other one is that the external disturbance amplified by negativity in a low stability ***,the impedance reshaping method for stability improvement of the system can be further *** validity of the simplified criterion is verified theoretically and experimentally by a positive damping reshaping method.

关键词： DC cascaded system,impedance model impedance reconstruction stability criterion

managing the surge:A comprehensive review of the entire disposal framework for retired lithium-ion batteries from electric vehicles

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Journal of Energy Chemistry 2024年第5期92卷 648-680页

作者： Ruohan Guo Feng Wang m.Akbar Rhamdhani Yiming Xu Weixiang shen Department of Engineering Technologies School of ScienceComputing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia Department of Chemistry and Biotechnology School of ScienceComputing and Engineering TechnologiesSwinburne University of TechnologyMelbourne VIC 3122Australia Department mechanical and Product Design Engineering School of EngineeringSwinburne University of TechnologyMelbourne VIC 3122Australia

Anticipating the imminent surge of retired lithium-ion batteries(R-LIBs)from electric vehicles,the need for safe,cost-effective and environmentally friendly disposal technologies has *** paper seeks to offer a comprehensive overview of the entire disposal framework for R-LIBs,encompassing a broad spectrum of activities,including screening,repurposing and ***,we delve deeply into a thorough examination of current screening technologies,shifting the focus from a mere enumeration of screening methods to the exploration of the strategies for enhancing screening ***,we outline battery repurposing with associated key factors,summarizing stationary applications and sizing methods for R-LIBs in their second life.A particular light is shed on available reconditioning solutions,demonstrating their great potential in facilitating battery safety and lifetime in repurposing scenarios and identifying their techno-economic *** the realm of battery recycling,we present an extensive survey of pre-treatment options and subsequent material recovery ***,we introduce several global leading recyclers to illustrate their industrial processes and technical ***,relevant challenges and evolving trends are investigated in pursuit of a sustainable end-of-life management and disposal *** hope that this study can serve as a valuable resource for researchers,industry professionals and policymakers in this field,ultimately facilitating the adoption of proper disposal practices.

关键词： Lithium-ion battery Battery reproposing and recycling miaieiials recovery technologies Techno-economic issues End-of-life management Disposal framework

Fire resistance evaluation through synthetic fire tests and generative adversarial networks

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 587-614页

作者： Aybike Özyüksel Çiftçioğlu m.z.Naser Department of Civil Engineering Manisa Celal Bayar University45140Türkiye School of Civil&Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSC 29631USA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSC 29631USA

This paper introduces a machine learning approach to address the challenge of limited data resulting from costly and time-consuming fire experiments by enlarging small fire test data sets and predicting the fire resistance of reinforced concrete *** approach begins by creating deep learning models,namely generative adversarial networks and variational autoencoders,to learn the spatial distribution of real fire *** then use these models to generate synthetic tabular samples that closely resemble realistic fire resistance values for reinforced concrete *** generated data are employed to train state-of-the-art machine learning techniques,including Extreme Gradient Boost,Light Gradient Boosting machine,Categorical Boosting Algorithm,Support Vector Regression,Random Forest,Decision Tree,multiple Linear Regression,Polynomial Regression,Support Vector machine,Kernel Support Vector machine,Naive Bayes,and K-Nearest Neighbors,which can predict the fire resistance of the columns through regression and *** learning analyses achieved highly accurate predictions of fire resistance values,outperforming traditional models that relied solely on limited experimental *** study highlights the potential for using machine learning and deep learning analyses to revolutionize the field of structural engineering by improving the accuracy and efficiency of fire resistance evaluations while reducing the reliance on costly and time-consuming experiments.

关键词： deep learning fire resistance generative adversarial networks machine learning

Asymmetrical Fault Current Calculation method and Influencing Factors Analysis of Droop-Controlled Inverters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 562-573页

作者： Huimin zhao zhikang Shuai Jun Ge An Luo Weimin Wu z.John shen College of Electrical and Information Engineering Hunan UniversityChangsha 410006China Electrical Engineering Department Shanghai Maritime UniversityShanghai 201306China Department of Electrical and Computer Engineering Ilinois Institute of TechnologyChicagoIL 60616 USA

Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten the safety of the microgrid. Therefore, it is imperative to conduct a comprehensive fault analysis of the inverter to guide the design of protection schemes. However, due to the complexity of droop control strategy, existing literatures have simplified asymmetric fault analysis of droop-controlled inverters to varying degrees. Therefore, accurate fault analysis of a droop-controlled inverter is needed. In this paper, by analyzing the control system, an accurate fault model is established. Based on this, a calculation method for instantaneous asymmetrical fault current is proposed. In addition, the current components and current characteristics are analyzed. It was determined that fault currents are affected by control loops, fault types, fault distance and nonlinear limiters. In particular, the influences of limiters on the fault model, fault current calculation and fault current characteristics were analyzed. Through detailed analysis, it was found that dynamics of the control loop cannot be ignored, the fault type and fault distance determine fault current level, and part of the limiters will totally change the fault current trend. Finally, calculation and experimental results verify the correctness of the proposed method.

关键词： Asymmetrical fault analysis droop control fault current calculation method limiter transient fault characteristics

Dysregulation of RNA modification systems in clinical populations with neurocognitive disorders

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Neural Regeneration Research 2024年第6期19卷 1256-1261页

作者： Helen m.Knight merve DemirbugenÖz Adriana PerezGrovas-Saltijeral Division of Cells Organisms and Molecular GeneticsSchool of Life SciencesUniversity of NottinghamNottinghamUK Department of Pharmaceutical Toxicology Faculty of PharmacyAnkara UniversityAnkaraTurkey

The study of modified RNA known as epitranscriptomics has become increasingly relevant in our understanding of disease-modifying *** of N6 adenosine(m^(6)A)and C5 cytosine(m^(5)C)bases occur on mRNAs,tRNA,mt-tRNA,and rRNA species as well as non-coding *** emerging knowledge of RNA binding proteins that act as writer,reader,and eraser effector proteins,comes a new understanding of physiological processes controlled by these *** processes when spatiotemporally disrupted within cellular nanodomains in highly specialized tissues such as the brain,give rise to different forms of *** this review,we discuss accumulating evidence that changes in the m^(6)A and m^(5)C methylation systems contribute to neurocognitive *** studies first identified mutations within FmR1 to cause intellectual disability Fragile X syndromes several years before FmR1 was identified as an m^(6)A RNA reader ***,familial mutations within the m^(6)A writer gene mETTL5,m^(5)C writer genes NSUN2,NSUN3,NSUN5,and NSUN6,as well as THOC2 and THOC6 that form a protein complex with the m^(5)C reader protein ALYREF,were recognized to cause intellectual development ***,differences in expression of the m^(5)C writer and reader effector proteins,NSUN6,NSUN7,and ALYREF in brain tissue are indicated in individuals with Alzheimer's disease,individuals with a high neuropathological load or have suffered traumatic brain ***,an abundance of m^(6)A reader and anti-reader proteins are reported to change across brain regions in Lewy bodies diseases,Alzheimer's disease,and individuals with high cognitive reserve.m^(6)A-modified RNAs are also reported significantly more abundant in dementia with Lewy bodies brain tissue but significantly reduced in Parkinson's disease tissue,whilst modified RNAs are misplaced within diseased cells,particularly where synapses are *** parahippocampal brain tissue,m^(6)A modification is enri

关键词： 5-methylcytosine methylation Alzheimer's disease cognitive diseases epitranscriptomics intellectual disability Lewy body diseases N6 adenosine RNA modification

Detailed analysis of the relativistic configuration of Bardeen anisotropic spheres in modified f(G)gravity

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Communications in Theoretical Physics 2024年第6期76卷 45-56页

作者： Adnan malik Ayesha Almas Tayyaba Naz Rubab manzoor m z Bhatti School of mathematical Sciences Zhejiang Normal UniversityJinhuaZhejiangChina Department of mathematics University of Management and TechnologySialkot CampusLahorePakistan National University of Computer and Emerging Sciences Lahore CampusPakistan Department of mathematics University of Management and TechnologyJohar Town CampusLahore 54782Pakistan Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The aim of this work is to investigate anisotropic compact objects within the framework of f(G)modified theory of *** our present work,we utilize Krori-Barua metrics,i.e.,λ(r)=Xr^(2)+Y andβ(r)=zr^(2).We use some matching conditions of spherically symmetric spacetime with Bardeen's model as an exterior ***,we establish some expressions of energy density and pressure components to analyze the stellar configuration of Bardeen compact stars by assuming viable f(G)*** examine the energy conditions for different stellar structures to verify the viability of our considered ***,we also investigate some other physical features,such as equilibrium condition,equation of state parameters,adiabatic index,stability analysis,mass function,surface redshift,and compactness factor,*** is worthwhile to mention here for the current study that our stellar structure in the background of Bardeen's model is more viable and stable.

关键词： Bardeen compact stars f(G)modified gravity Krori-Barua potential