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Advances in manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang Pei-da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of machinery manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Failure pattern in ceramic metallic target under ballistic impact

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Defence Technology（防务技术） 2024年第10期40卷 173-190页

作者： m.A.Iqbal m.K.Khan Department of Civil Engineering Indian Institute of Technology RoorkeeRoorkee 247667India Department of Civil Engineering Aligarh Muslim UniversityAligarh202002India

The ballistic resistance and failure pattern of a bi-layer alumina 99.5%-aluminium alloy 1100-H12 target against steel 4340 ogival nosed projectile has been explored in the present experimental cum numerical *** the experimental investigation,damage induced in the ceramic layer has been quantified in terms of number of cracks developed and failure zone *** resultant damage in the backing layer has been studied with variation in the bulge and perforation hole in the backing layer with the varying incidence *** discussion of the experimental results has been further followed by three dimensional finite element computations using ABAQUS/Explicit finite code to investigate the behaviour of different types of bi-layer targets under multi-hit projectile *** JH-2 constitutive model has been used to reproduce the behaviour of alumina 99.5%and JC constitutive model has been used for steel 4340 and aluminium alloy *** total energy dissipation has been noted to be of lesser magnitude in case of sub-sequential impact in comparison to simultaneous impact of two *** distance between the impact points of two projectiles also effected the ballistic resistance of bi-layer *** ballistic resistance of single tile ceramic front layer and four tile ceramic of equivalent area found to be dependent upon the boundary conditions provided to the target.

关键词： Ballistic resistance Bi-layer target Ceramic metal armour multi-hit impact Finite element modelling

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.Hamad Nidal Dwaikat m.H.A.mhareb m.I.Sayyed R.m.Hamad Y.S.m.Alajerami m.A.Almessiere Gameel Saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding mass stopping power Rare earths

Surface activation of viscose textiles via air,argon,and oxygen dielectric barrier discharge plasma:influence of peak voltage

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Plasma Science and Technology 2024年第7期26卷 134-147页

作者： Shrouk ELASHRY Usama m.RASHED mostafa A.WAHBA Hend m.AHmED Nabil m.ELSIRAGY Plasma Laboratory Physics DepartmentFaculty of scienceTanta UniversityTanta 31527Egypt Physics Department Faculty of Science(Male)Al-Azhar UniversityCairo 11651Egypt Textile Research Industrial Division National Research CentreDokkiGiza 12622Egypt

This paper discusses the use of atmospheric pressure dielectric barrier discharge(DBD)plasma treatment to enhance the surface qualities of viscose *** study explores the effects of different plasma gases,discharge voltages,and exposure times on the treated *** findings emphasize the importance of optimizing the plasma's peak voltage to achieve the desired surface treatment *** document also presents data on colour strength,wettability,colour fastness,and tensile strength of the treated fabrics,as well as scanning electron microscopy(SEm)analysis of surface morphology and chemical analysis using fouriertransition infrared spectroscopy(FTIR)and energy dispersive X-ray(EDX).The results show that treatment at a peak voltage of 11.83 k V is more efficient,except for the tensile strength which is enhanced at a peak voltage of 8.92 k *** oxygen plasma treatment significantly improves the colour strength,which exhibits an increase from 11 to *** intensified colour was attributed to the significant influence of electrostatic interactions between the charged hydroxyl groups of the oxygen plasma treated viscose textiles and the dye molecules,which enhance the *** oxygen DBD plasma exhibits a higher ability to enhance the properties of textiles when compared to air and argon *** study presents a sustainable,economical,secure,and ecologically friendly approach to explore new fabrics for specific uses.

关键词： Lissajous diagrams printability wettability tensile strength SEm EDX FTIR

Classifying moisture sources associated with snowfall in the mountains of Lesotho

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Journal of mountain Science 2024年第6期21卷 1941-1953页

作者： Alexi m.mARINAKI Jennifer m.FITCHETT School of Geography Archaeology and Environmental StudiesUniversity of the WitwatersrandPrivate Bag X3Wits 2050South Africa

An average of eight snowfall events occur each year in the eastern Lesotho *** snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude ***,the moisture sources of the snowfall are unclassified and *** Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,an air mass back trajectory model,has been used to evaluate moisture source waters locally in southern Africa and internationally in China and *** study uses HYSPLIT to determine the source moisture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was compiled using the Snow Report SA Instagram page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of *** amounts to models of moisture source trajectories for 28 and 82 snowfall days,*** air mass pathways are classified according to their frequency per snowfall event,per month in the snow season,per year and for the full *** this,associated moisture source regions and dominant air mass trajectories were *** study reports that the air mass trajectories associated with Afriski and Lesotho as a whole are very *** most common pathway of air mass trajectories transporting snow-bearing moisture to Lesotho was an inland trajectory from the northern regions of southern *** pathway makes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the *** High Pressure.

关键词： Eastern Lesotho Highlands Afriski Snow Cut-off Lows HYSPLIT Synoptic Climatology

Small-scale self-driving cars:A systematic literature review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 271-292页

作者： Felipe Caleffi Lauren da Silva Rodrigues Joice da Silva Stamboroski Brenda medeiros Pereira Autonomous Vehicles Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil mobility and Logistics Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil

The autonomous vehicle(AV)technology has the potential to significantly improve safety and efficiency of the transportation and logistics ***-scale AV testing is limited by time,space,and cost,while simulation-based testing often lacks the necessary accuracy of AV and environmental *** recent years,several initiatives have emerged to test autonomous software and hardware on scaled *** systematic literature review provides an overview of the literature surrounding small-scale self-driving cars,summarizing the current autonomous platforms deployed and focusing on the software and hardware developments in this *** studies published in English-language journals or conference papers that present small-scale testing of self-driving cars were *** of Science,Scopus,Springer Link,Wiley,ACm Digital Library,and TRID databases were used for the literature *** systematic literature search found 38 eligible *** gaps in the reviewed papers were identified to provide guidance for future *** key takeaway emerging from this manuscript are:(i)there is a need to improve the models and neural network architectures used in autonomous driving systems,as most papers present only preliminary results;(ii)increasing datasets and sharing databases can help in developing more reliable control policies and reducing bias and variance in the training process;(iii)small-scaled vehicles to ensure safety is a major benefit,and incorporating data about unsafe driving behaviors and infrastructure problems can improve the accuracy of predictive models.

关键词： Self-driving car Autonomous vehicle Small-scale vehicle Systematic literature review

Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEmATI m.SEFID A.KARImIPOUR A.J.CHAmKHA Faculty of mechanical Engineering Yazd UniversityYazd ***Iran Department of mechanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(mF)is very vital due to its existence in various sectors of industry and *** present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection *** temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is *** formulation of the problem is derived with the lattice Boltzmann method(LBm)by code writing via the FORTRAN *** variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed mF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are *** findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates *** is the lowest cooling performance index and mF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research.

关键词： thermal performance analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity

Impact of carbimazole combined with vitamin E on testicular injury induced by experimental hyperthyroidism in adult albino rats:oxidative/inflammatory/apoptotic pathways

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Asian Journal of Andrology 2024年第4期26卷 396-401页

作者： Ramadan S Hussein moustafa m Eyada Rashad m mostafa Samah m Elaidy Shereen H Elsayed Hany m Saad Department of Dermatology College of Medicine Prince Sattam Bin Abdulaziz UniversityAl-Kharj 16242Saudi Arabia Department of Dermatology Andrology and STDsAssiut Police HospitalAssiut 71525Egypt Department of Dermatology Venereology and AndrologyFaculty of MedicineSuez Canal UniversityIsmailia 41522Egypt Department of Andrology and Sexology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Clinical Pharmacology Faculty of MedicineSuez Canal UniversityIsmailia 41511Egypt Department of Rehabilitation Sciences Faculty of Health and Rehabilitation SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh 12271Saudi Arabia.

Thyroid hormones play essential roles in spermatogenesis,but their effects on infertile males remain poorly *** study aimed to evaluate the impact of combining carbimazole(CBZ)with vitamin E(VE)on testicular injury induced by experimental hyperthyroidism in adult albino rats,focusing on oxidative,inflammatory,and apoptotic *** this experimental study,64 adult male albino Wistar rats were divided into eight groups:Group I(control-untreated),Group II(CBZ-control),Group III(VE-control),Group IV(CBZ+VE-control),Group V(levothyroxine-induced testicular injury),Group VI(levothyroxine+CBZ-treated),Group VII(levothyroxine+VE-treated),and Group VIII(levothyroxine+CBZ+VE-treated).The study was conducted in the Faculty of medicine,Suez Canal University(Ismailia,Egypt).After cervical decapitation,both testes and epididymis were examined histopathologically and *** differences were observed among groups concerning malondialdehyde(mda),glutathione(GSH),superoxide dismutase(SOD),and catalase(CAT;all Pmerase chain reaction analysis showed significant differences in tumor necrosis factor-α(TNF-α),interleukin-10(IL-10),Bcl-2-associated X protein(BAX),B-cell lymphoma 2 protein(Bcl2),p53,Caspase-3,Caspase-8,Caspase-9,and nuclear factor-kappa B(NF-κB)mRNA levels(all Pminiferous tubules and ***,the Group VIII showed improved spermatogenesis and a decrease in testicular side *** addition of VE to the treatment of hyperthyroid rats with CBZ reduced testicular side effects and seminiferous tubular affection when potentially improving *** research is needed to elucidate the underlying mechanisms fully.

关键词： antithyroid drugs testicular injury thyroid gland vitamin E

On the global smooth solutions of 3D incompressible Hall-mHD equations

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Applied mathematics(A Journal of Chinese Universities) 2024年第2期39卷 319-327页

作者： YUE Gao-cheng SUN Wen-da School of mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China

The present paper is devoted to the well-posedness issue for the 3D incompressible Hall-mHD system obtained from kinetic models. Our analysis strongly relies on the use of the Fourier analysis. We establish the global existence of smooth solutions for a class of large initial data, this result implies the initial velocity and magnetic field can be arbitrarily large.

关键词： 3D Hall-mHD well-posedness Fourier analysis

CFD-DEm analysis of particle polydispersity on the performance of fluidised bed reactor during silane pyrolysis Author links open overlay panel

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Particuology 2024年第8期91卷 72-87页

作者： Akshayveer Vijay m.Shinde mS2Discovery Interdisciplinary Research Institute Wilfrid Laurier UniversityWaterlooOntarioN2L3C5Canada Department of Chemical Engineering Indian Institute of Technology(BHU)Varanasi221005India

A CFD-DEm model is developed for chemical vapour deposition of silane in a fluidized bed reactor to investigate the effect of polydispersity on local phase dynamics,mass and heat transport,as well as the rate of Si *** gas-phase fines formation and heterogeneous deposition on the seed particle,as well as the scavenging effect for Si particle growth,are *** method is first validated against the experimentally measured Si deposition rate,percentage of fine production and minimum fluidisation ***,the properties,primarily particle intermixing,fluidisation behaviour and bubble dynamics along with the deposition process,are analyzed for several polydisperse beds under various operating *** effect of polydispersity of the bed on a fraction of the bubble size,dense phase expansion and interchange coefficient between various phases is thoroughly investigated to establish a correlation with reactor *** results show that broad-Gaussian particle size distribution(PSD)exhibits excellent improvement in fluidisation behaviour,resulting in a high deposition rate,and minimum formation of Si fines.

关键词： CFD-DEm method Chemical vapour deposition(CVD) Particle size distribution Silicon Gas-solid fluidized bed