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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 563-580页

作者： N.HUmNEKAR d.SRINIVASACHARYA department of mathematics National Institute of TechnologyWarangal 506004TelanganaIndia

The influence of variable viscosity and double diffusion on the convective stability of a nanofluid flow in an inclined porous channel is *** darcyBrinkman model is used to characterize the fluid flow dynamics in porous *** analytical solutions are obtained for the unidirectional and completely developed *** on a normal mode analysis,the generalized eigenvalue problem under a perturbed state is *** eigenvalue problem is then solved by the spectral ***,the critical Rayleigh number with the corresponding wavenumber is evaluated at the assigned values of the other flow-governing *** results show that increasing the darcy number,the lewis number,the dufour parameter,or the Soret parameter increases the stability of the system,whereas increasing the inclination angle of the channel destabilizes the ***,the flow is the most unstable when the channel is vertically oriented.

关键词： nanofluid inclined channel variable viscosity linear stability double dif-fusion porous medium

基于深度神经网络模拟复杂多孔介质中两相驱替过程

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石油勘探与开发 2024年第5期51卷 1126-1140页

作者： ASAdOLAHPOUR Seyed Reza JIANG Zeyun lewis Helen 闵超赫瑞瓦特大学能源、地球科学、基础设施与社会学院地球能源工程研究所爱丁堡EH144AS英国西南石油大学理学院成都610500 油气藏地质及开发工程全国重点实验室西南石油大学成都610500

为了预测复杂孔隙结构中毛管压力主导下两相流排驱过程中的流体分布,从仿真多孔介质和岩石CT图像中抽取子样本,并采用孔隙形态模拟器(PmS)生成流体分布,以创建多样化的数据集,将距离图及像素大小、界面张力、接触角、压力作为输入参数,... 详细信息

为了预测复杂孔隙结构中毛管压力主导下两相流排驱过程中的流体分布,从仿真多孔介质和岩石CT图像中抽取子样本,并采用孔隙形态模拟器(PmS)生成流体分布,以创建多样化的数据集,将距离图及像素大小、界面张力、接触角、压力作为输入参数,通过改造、训练、评估卷积神经网络(CNN)、递归神经网络(RNN)和视觉转换器(ViT),优选用于预测流体分布的模型。模拟分析表明,常用的卷积和递归神经网络在捕捉流体连通性方面存在不足。基于ViT构建了一个高维视觉转换器(Hd-ViT),该转换器先忽略孔隙的空间位置仅根据其大小进行排驱,再在后处理步骤中追加流体连通要求,这种方法允许在任何坐标方向预设出入口,并使用不同尺寸和不同分辨率的图像进行渗流状态推断。通过在砂岩和碳酸盐岩大图像上验证,并与微流控驱替测试的实验结果比较,证实了Hd-ViT模型的有效性、精确性和速度优势,且在捕捉孔隙尺度三维流动方面存在较大的潜力。

关键词：两相驱替流体分布深度神经网络视觉转换器孔隙形态模拟器大数据集

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胰岛素对昆虫病原线虫生长发育、生殖力及致病力的影响

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中国生物防治学报 2024年第4期40卷 856-865页

作者：钱秀娟孙丹臧建成 Edwin E.lewis 甘肃农业大学植物保护学院/甘肃省农作物病虫害生物防治工程实验室西藏农牧学院植物科学学院美国爱达荷大学农业与生命科学学院昆虫学植物病理学及线虫学系

昆虫病原线虫是一种极具潜力的生防因子，因其高效的杀虫特性而受到国际生防界的广泛关注，胰岛素作为一种蛋白质多肽，已被证实对昆虫、线虫等的生长发育、寿命均有重要调控作用。为了明确胰岛素对昆虫病原线虫的影响，本试验通过对经... 详细信息

昆虫病原线虫是一种极具潜力的生防因子，因其高效的杀虫特性而受到国际生防界的广泛关注，胰岛素作为一种蛋白质多肽，已被证实对昆虫、线虫等的生长发育、寿命均有重要调控作用。为了明确胰岛素对昆虫病原线虫的影响，本试验通过对经卡森斯氏线虫Steinernemakraussei0657L和短尾异小杆线虫Heterorhabditisbrevicaudis0641TY侵染的大蜡螟Galleriamellonella注射不同浓度胰岛素，观测昆虫病原线虫的生活史及其对大蜡螟的致病力，以明确胰岛素对昆虫病原线虫生长发育、生殖力、致病力的影响。结果表明：胰岛素干预时间和干预浓度均可对卡森斯氏线虫0657L在寄主昆虫体内的生长发育产生影响，侵染当天（t）干预和高浓度（1:500）干预，会明显缩短其发育历期；侵染当天无论是高浓度还是低浓度的胰岛素干预，均会明显缩短短尾异小杆线虫0641TY的发育历期，且相比较卡森斯氏线虫0657L，胰岛素促进短尾异小杆线虫0641TY发育历期的效果更明显。在卡森斯氏线虫0657L侵染大蜡螟10 d后，注射低浓度的胰岛素，可显著提高其生殖力；在短尾异小杆线虫0641TY侵染大蜡螟1d后，注射低浓度的胰岛素，可显著提高其生殖力。胰岛素对卡森斯氏线虫0657L致病力有影响，在24 h内高浓度胰岛素可显著缩短寄主昆虫的死亡时间，但是侵染36 h后，各处理间差异不显著；而对短尾异小杆线虫0641TY致病力无影响。综上所述，胰岛素对卡森斯氏线虫0657L和短尾异小杆线虫0641TY的发育和生殖力均有影响，且对卡森斯氏线虫致病力有影响。

关键词：胰岛素昆虫病原线虫生长发育生殖力致病力

Fuzzy difference Equations in diagnoses of Glaucoma from Retinal Images Using deep Learning

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Computer modeling in Engineering & Sciences 2024年第4期139卷 801-816页

作者： d.dorathy Prema Kavitha L.Francis Raj Sandeep Kautish Abdulaziz S.Almazyad Karam m.Sallam Ali Wagdy mohamed department of mathematics Voorhees CollegeVelloreTamil NaduIndia Chandigarh Group of Colleges JhanjeriMohaliPunjabIndia department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia Faculty of Science and Technology School of IT and SystemsUniversity of CanberraCanberraAustralia Operations Research department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGiza12613Egypt Applied Science Research Center Applied Science Private UniversityAmman11937Jordan

The intuitive fuzzy set has found important application in decision-making and machine *** enrich and utilize the intuitive fuzzy set,this study designed and developed a deep neural network-based glaucoma eye detection using fuzzy difference equations in the domain where the retinal images *** image detections are categorized as normal eye recognition,suspected glaucomatous eye recognition,and glaucomatous eye *** degrees associated with weighted values are calculated to determine the level of concentration between the fuzzy partition and the retinal *** proposed model was used to diagnose glaucoma using retinal images and involved utilizing the Convolutional Neural Network(CNN)and deep learning to identify the fuzzy weighted regularization between *** methodology was used to clarify the input images and make them adequate for the process of glaucoma *** objective of this study was to propose a novel approach to the early diagnosis of glaucoma using the Fuzzy Expert System(FES)and Fuzzy differential equation(FdE).The intensities of the different regions in the images and their respective peak levels were *** the peak regions were identified,the recurrence relationships among those peaks were then *** partitioning was done due to varying degrees of similar and dissimilar concentrations in the *** and dissimilar concentration levels and spatial frequency generated a threshold image from the combined fuzzy matrix and *** distinguished between a normal and abnormal eye condition,thus detecting patients with glaucomatous eyes.

关键词： Convolutional Neural Network(CNN) glaucomatous eyes fuzzy difference equation intuitive fuzzy sets image segmentation retinal images

Aerodynamics of a Tandem-Bladed Axial Compressor Rotor under Circumferential distortion at different Rotational Speeds

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Journal of Thermal Science 2024年第4期33卷 1340-1356页

作者： Amit KUmAR Jerry T.JOHN A.m.PRAdEEP R.A.dAKKERmANS dragan KOZULOVIC department of Aerospace Engineering Indian Institute of Technology BombayMumbai400076India department of Automotive and Aeronautical Engineering Hamburg University of Applied Sciences20099HamburgGermany Institute of Jet Propulsion Bundeswehr University Munich85577NeubibergGermany

For most aircraft engines,inflow distortion is *** distortion is known to degrade the aerodynamic performance and stable operating limits of a *** rotor configuration is an arrangement that effectively controls the growth of the boundary layer over the suction surface of the ***,a higher total pressure rise can be achieved through this unconventional design approach involving the splitting of the blade into forward and aft *** is expected that the effect of inlet flow distortion would be more severe for a tandem-rotor design due to the greater flow turning inherent in such ***,this aspect needs to be thoroughly *** present study discusses the effect of circumferential distortion on the tandem-rotor at different rotational ***-annulus RANS simulations using ANSYS CFX are used in the present *** performance of the rotor at a particular flow coefficient and different rotational speeds is *** total pressure and efficiency are observed to drop at lower mass flow rates under the influence of circumferential *** loss region in each blade passage is mainly associated with the blade wake,tip leakage vortex,secondary flow,and boundary ***,their contribution varies from passage to passage,particularly in the distorted *** the lower span,the wake width is found to be higher than that at a higher *** to the redistribution of the mass flow,the circumferential extent reduces at a higher *** the undistorted sector,the strength of the tip leakage vortex is significantly higher at the design rotational speed than at lower *** distortion near the tip region promotes an early vortex breakdown even at the design operating *** adversely affects the total pressure,efficiency,and stall *** clean flow conditions,this phenomenon is only observed near the stall *** the design operating condition,the breakdown of the forward rotor tip l

关键词： tandem rotor circumferential distortion loss tip leakage vortex vortex breakdown diffusion factor aerodynamics of compressor blade

BaTiO3 solid solutions co-doped with Gd3+ and Eu3+:Synthesis,structural evolution and dielectric properties

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Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.martínez-López m.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández m.Reyes-Pérez m.I.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.I.dávila-Pulido Academic Area of Earth Sciences and materials Autonomous University of Hidalgo State metallurgy and materials department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 mPa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRd） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO3 doping Europium Gadolinium Rare earths Synthesis

Improved Leap-frog method for Time-domain Fault Location

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Journal of modern Power Systems and Clean Energy 2024年第2期12卷 670-674页

作者： Izudin džafić Rabih A.Jabr Faculty of Electrical Engineering University of SarajevoSarajevo 71000Bosnia and Herzegovina department of Electrical and Computer Engineering American University of BeirutBeirut 11072020Lebanon IEEE

The partial differential equation(PdE)solution of the telegrapher is a promising fault location method among time-domain and model-based *** research works have shown that the leap-frog process is superior to other explicit methods for the PdE ***,its implementation is challenged by determining the initial conditions in time and the boundary conditions in *** letter proposes two implicit solution methods for determining the initial conditions and an analytical way to obtain the boundary conditions founded on the signal *** results show that the proposal gives fault location accuracy superior to the existing leap-frog scheme,particularly in the presence of harmonics.

关键词： Fault location leap-frog partial differential equation time-domain analysis transmission line

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on mg-alloy

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Journal of magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： d.V.mashtalyar I.m.Imshinetskiy V.V.Kashepa K.V.Nadaraia m.A.Piatkova A.I.Pleshkova K.A.Fomenko A.Yu.Ustinov S.L.Sinebryukhov S.V.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical dermatovenerological dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on mA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARd m.J.mAHmOOdI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(Fd)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

The Effect of External magnetic Field on Electron Scale Kelvin–Helmholtz Instability

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Research in Astronomy and Astrophysics 2024年第9期24卷 236-247页

作者： d.Tsiklauri Joule Physics Laboratory School of ScienceEngineering and EnvironmentUniversity of SalfordManchesterM54WTUK

We use particle-in-cell,fully electromagnetic,plasma kinetic simulation to study the effect of external magnetic field on electron scale Kelvin–Helmholtz instability(ESKHI).The results are applicable to collisionless plasmas when,e.g.,solar wind interacts with planetary magnetospheres or a magnetic field is generated in AGN *** find that as in the case of magnetohydrodynamic(mHd)KHI,in the kinetic regime,the presence of an external magnetic field reduces the growth rate of the *** the mHd case,there is a known threshold magnetic field for KHI stabilization,while for ESKHI this is to be analytically *** a kinetic analytical expression,we use several numerical simulation runs to establish an empirical dependence of ESKHI growth rate,Γ(B_(0))ω_(pe),on the strength of the applied external magnetic *** find the best fit is hyperbolic,Γ(B_(0))ω_(pe)=Γ_(0)ω_(pe)/(A+BB_(0)),where Γ_(0) is the ESKHI growth rate without an external magnetic field and B_(0)=B_(0)/B_(mHd)is the ratio of external and two-fluid mHd stability threshold magnetic field,derived *** analytical theory to back up this growth rate dependence on the external magnetic field is *** results suggest that in astrophysical settings where a strong magnetic field pre-exists,the generation of an additional magnetic field by the ESKHI is suppressed,which implies that nature provides a“safety valve”—natural protection not to“over-generate”magnetic field by the ESKHI ***,we find that our two-fluid mHd threshold magnetic field is the same(up to a factor √γ_(0))as the dC saturation magnetic field,previously predicted by fully kinetic theory.

关键词： instabilities magnetic fields plasmas Sun:heliosphere ISm:magnetic fields