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An Innovative Finite Element Geometric Modeling of Single-Layer Multi-Bead WAAMed Part

Computer Modeling in Engineering & Sciences 2024年第3期138卷 2383-2401页

作者： Xiangman Zhou Jingping Qin Zichuan Fu Min Wang Youlu Yuan Junjian Fu Haiou Zhang seyed Reza Elmi hosseini College of Mechanical and Power Engineering China Three Gorges UniversityYichang443002China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China School of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmakIran

Finite element (FE) coupled thermal-mechanical analysis is widely used to predict the deformation and residualstress of wire arc additive manufacturing (WAAM) parts. In this study, an innovative single-layermulti-bead profilegeometric modeling method through the isosceles trapezoid function is proposed to build the FE model of theWAAMprocess. Firstly, a straight-line model for overlapping beads based on the parabola function was establishedto calculate the optimal center distance. Then, the isosceles trapezoid-based profile was employed to replace theparabola profiles of the parabola-based overlapping model to establish an innovative isosceles trapezoid-basedmulti-bead overlapping geometric model. The rationality of the isosceles trapezoid-based overlapping model wasconfirmed by comparing the geometric deviation and the heat dissipation performance index of the two overlappingmodels. In addition, the FE-coupled thermal-mechanical analysis, as well as a comparative experiment of thesingle-layer eight-bead deposition process show that the simulation results of the above two models agree with theexperimental results. At the same time, the proposed isosceles trapezoid-based overlappingmodels are all straightlineprofiles, which can be divided into high-quality FE elements. It can improve the modeling efficiency andshorten the simulation calculation time. The innovative modeling method proposed in this study can provide anefficient and high-precision geometricmodelingmethod forWAAMpart FE coupled thermal-mechanical analysis.

关键词： WAAM FE coupled thermal-mechanical analysis the isosceles trapezoid-based model residual stress

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Exploring the relationship between Hashimoto's thyroiditis and male fertility:A meta-analytic and meta-regression perspective on hormonal and seminal factors

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Asian pacific Journal of Reproduction 2024年第4期13卷 147-159页

作者： seyed Sobhan Bahreiny mojtaba Aghaei Mahdi Amraei Mohammad Reza Dabbagh Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Medical Basic Sciences Research Institute Physiology Research CenterDepartment of PhysiologySchool of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Thalassemia&Hemoglobinopathy Research Center Health Research InstituteAhvaz Jundishapur University of Medical SciencesAhvazIran USERN Office Ahvaz Jundishapur University of Medical SciencesAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran

Objective:To explore the relationship between Hashimoto's autoimmune hypothyroidism(HT)and male fertility,focusing on hormonal and seminal ***:A systematic literature search was conducted across databases such as PubMed,Web of Science,EMBASE,Scopus,Cochrane,and Google Scholar,covering studies published from January 2000 to March *** investigating the impact of HT on semen quality parameters and reproductive hormones were *** effect estimates were calculated using standard mean difference(SMD)and 95%confidence intervals(CI).Results:A total of 8 studies with 8965 participants were *** significantly affected semen quality and reproductive hormone ***,there was a notable decrease in progressive morphology(SMD=-0.78;95%CI:-1.40 to-0.17;P=0.01)and sperm motility(SMD=-1.151;95%CI:-1.876 to-0.425;P=0.002).In addition,there were no significant changes in reproductive hormones,although there were elevated levels of luteinizing hormone(SMD=0.437;95%CI:0.000 to 0.874;P=0.050)and follicle-stimulating hormone(SMD=0.293;95%CI:-0.171 to 0.758;P=0.216),with a slight impact on testosterone levels(SMD=-1.143;95%CI:-2.487 to 0.200;P=0.095).Conclusions:This systematic review and meta-analysis provides robust evidence of the detrimental effects of HT on semen quality and reproductive hormones,underscoring the necessity for thorough evaluation and management of thyroid function in male infertility assessments.

关键词： Hashimoto thyroiditis Male fertility Semen quality Reproductive hormones Meta-analysis Meta-regression

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Enhanced microstructural and mechanical properties of Stellite/WC nanocomposite on Inconel 718 deposited through vibration-assisted laser cladding

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 327-334页

作者： Hossein hosseini-Tayeb seyed Mahdi Rafiaei Daneshpajoohan Pishro Higher Education Institute IsfahanIran Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayeganIsfahanIran

Stellite-21/WC nanopowders were deposited on Inconel through vibration-assisted laser cladding with different laser *** and scanning electron microscopy,hardness measurements,and wear characterizations were employed to understand the microstructural and mechanical behaviors of the *** showed that varying the cooling rate exerted remarkable effects on the microstructure of the as-cladded ***,increasing the laser power from 150 W to 250 W increased the heat input and the *** was affected by the scanning rate and powder feeding rate at a high laser power of 250 *** WC nanoparticles were added as reinforcement,the dilution magnitude intensified while the hardness value increased from HV 350 to HV *** wear characterizations indicated that the composites containing 3 wt%WC nanoparticles possessed the highest wear resistance.

关键词： Stellite WC nanoparticles mechanical properties laser cladding

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Effect of Gaussian size distribution width on minimum fluidization velocity in tapered gas–solid fluidized beds

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Particuology 2022年第7期20卷 71-84页

作者： mojtaba Rasteh Goodarz Ahmadi S.H.hosseini Department of Chemical Engineering Hamedan University of TechnologyHamedanP.O.Box 65155-579Iran Department of Mechanical and Aeronautical Engineering Clarkson UniversityPotsdamNY 13699-5725USA Department of Chemical Engineering Ilam UniversityIlam 69315-516Iran

This paper investigated the effect of Gaussian distribution width,average particle diameter,particle loading,and the tapered angle on minimum fluidization velocity(U_(mf))by conducting extensive experiments in tapered fluidized *** powders with Gaussian size distribution and different distribution widths were used in the *** increase in U_(mf)with increasing the average particle diameter,particle loading,and the tapered angle was *** was also a nonmonotonic behavior of Umf as the Gaussian distribution width *** empirical correlation including dimensionless groups for predicting Umf in tapered beds was developed in which the effect of distribution width was *** proposed correlation predictions were in good agreement with the experimental data,with a maximum deviation of 16.5%and average and standard deviations of,respectively,6.4%and 7.4%.The proposed correlation was also compared with three earlier models,and their accuracy was discussed.

关键词： Tapered fluidized bed Minimum fluidization velocity Gaussian size distribution Distribution width Dimensional analysis

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Simultaneous Employment of Generation Rescheduling and Incentive-based Demand Response Programs for Congestion Management in Case of Contingency

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Journal of Modern Power Systems and Clean Energy 2022年第4期10卷 902-912页

作者： seyed Erfan hosseini Alimorad Khajehzadeh Mahdiyeh Eslami Department of Electrical Engineering Kerman branchIslamic Azad UniversityKermanIran

Relieving congestion significantly influences the operation and security of the transmission ***,the congestion alleviation of transmission network in all power systems is ***,it could prevent price spikes and/or involuntary load shedding and impose high expenses on the transimission network,especially in case of ***,the increasing or decreasing generation rescheduling has been used as one of the most imperative approaches for correctional congestion management when a contingency ***,demand response programs(DRPs)could also be a vital tool for managing the ***,the simultaneous employment of generation rescheduling and DRPs is proposed for congestion management in case of *** objective is to reschedule the generation of power plants and to employ DRPs in such a way so as to lessen the cost of *** crow search algorithm is employed to determine the *** accuracy and efficiency of the proposed approach are assessed through the tests conducted on IEEE 30-bus and 57-bus test *** results of various case studies indicate the better performance of the proposed approach in comparison with different approaches presented in the literature.

关键词： Congestion management demand response generation rescheduling transmission economy transmission lines

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A complex solution on the dynamic response of sandwich graphene-reinforced aluminum-based composite beams with copper face sheets under two moving constant loads on an elastic foundation

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International Journal of Mechanical System Dynamics 2023年第3期3卷 251-264页

作者： Mohammadreza Eghbali seyed Amirhosein hosseini Department of Mechanical Engineering University of ZanjanZanjanIran Department of Industrial Mechanical and Aerospace EngineeringBuein Zahra Technical UniversityQazvinIran

An analytical solution was used to investigate the elastic response of a sandwich beam with a graphene-reinforced aluminum-based composite(GRAC)on an elastic foundation using copper as the face layer of the functionally graded composite beam and a simply supported boundary ***'s higher-order shear deformation theory was utilized to derive the equations,which were solved in Laplace space and then converted into space–time using Laplace *** exact response of the GRAC sandwich beam was obtained by considering the displacement at the mid-span of the sandwich *** moving loads with different speed ratios were applied at a single point,and the effect of various parameters,including the spring constant,the speed ratio,the percentage of graphene,the moving load speed,and the distribution pattern,was *** study aimed to eliminate any overlap and improve the accuracy of the *** exact solving method presented has not been reported in other articles so ***,due to the difficulty of solving mathematical equations,this method is only applicable to simple boundary conditions.

关键词： GRAC beams moving load Laplace transform elastic foundation analytical solution aluminum-based

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Prediction of the Behavior of a Power System Using Root Cause Failure Analysis

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Fluid Dynamics & Materials Processing 2022年第3期18卷 815-833页

作者： seyed Mohammad seyed hosseini Kamran Shahanaghi Safar Shasfand Iran University of Science and Technology Tehran***Iran

The thermo-economic performance of a gas turbine is simulated using a fish bone technique to characterize the major equipment failure *** a fault tree analysis and a Pareto technique are implemented to identify the related failure modes,and the percentage and frequency of failures,respectively.A pump 101 and drier 301 belonging to the Tabriz Petrochemical Company are considered for such analysis,which is complemented with a regression method to determine a behavioral model of this equipment over a twenty-year *** findings indicate that 81%of major failure factors in production equipment are related to the executive procedures(24%),human error(22%),poor quality of materials and parts(20%),and lack of personnel training(15%).

关键词： Combined heat and power root analysis thermoeconomic performance fault tree Pareto behavioral model

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Assessment of assembly shape and geometric effects on amplification of shear waves using discrete element method

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Particuology 2022年第7期20卷 85-99页

作者： Leila Karbor seyed Majdeddin Mir Mohammad hosseini Ahad Bagherzadeh Khalkhali Civil and Environmental Engineering Faculty Amirkabir University of TechnologyTehranIran Civil Engineering Faculty Science and Research BranchIslamic Azad UniversityTehranIran

The discrete element method(DEM)is a capable tool used to simulate shear wave propagation in granular assemblies for many *** have studied assembly shapes such as rectangles(in 2D simulations)or cylinders and cubes(in 3D simulations).This paper aimed to qualify the effect of assembly shape on the shear wave propagation and maximum amplification in the vertical plane(horizontal and vertical directions)caused by this *** this end,shear wave propagations in different assembly shapes such as rectangle,trapezium,and triangle with rigid boundary conditions were simulated.A sine wave pulse was applied with a point source by moving a particle as the transmitter *** evaluate the shear wave velocity of the assemblies,the transmitter and receiver particles were *** the simulations were performed with 2D DEM which is a useful tool to determine the amount and location of the maximum amplification factor of the assembly in both horizontal and vertical *** advantage of this study was assessing the effect of parameters such as input wave frequency,assembly height,shape,and aspect ratios on the amplification of the input waves.

关键词： Wave propagation Granular assembly DEM Assembly shape Shear wave

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Strain Geometry and Vorticity Analysis of the Deformed Radiolarian Rocks in the Abade-Tashk Area,the Zagros Suture Zone,Iran

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Journal of Earth Science 2022年第2期33卷 525-540页

作者： Roghyeh Tavakkoli Khalil Sarkarinejad Saeede Keshavarz seyed Rahim hosseini Department of Earth Sciences School of ScienceShiraz UniversityShiraz ***Iran Department of Earth Sciences Graduate University of Advanced TechnologyKerman ***Iran

Deformation in the Zagros suture zone is a result of the oblique collision of the AfroArabian continent with the Central Iranian *** types of folding and faulting are characteristic features of the study area and indicate the performance of a high strain tectonic regime in this *** distinguish deformation geometry during the collisional events,strain measurements have been carried out,using the R_(f)/φ method on deformed radiolarian microfossils,in the Zagros suture *** on the results,the strain ellipsoid shape is in the range of general flattening to plane strain(K=0.16 – 1.12).Measured mean kinematic vorticity number(W_(m)) in the deformed radiolarian rocks ranges between 0.50 and 0.87,which implies that exhumation of the Abade-Tashk area was facilitated by a general shear flow(35%

关键词： transpression Zagros suture zone deformed radiolarian microfossils vorticity analysis Abade-Tashk area tectonicstranspression Zagros suture zone deformed radiolarian microfossils vorticity analysis Abade-Tashk area tectonics

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Robust Authentication and Session Key Agreement Protocol for Satellite Communications

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Computers, Materials & Continua 2022年第6期71卷 5891-5910页

作者： Somayeh Soltani seyed Amin hosseini Seno Juli Rejito Rahmat Budiarto Department of Computer Engineering Ferdowsi University of MashhadMashhad***Iran Faculty of Mathematics and Science Universitas PadjadjaranJatinangor45363Indonesia Faculty of Computer Science Universitas Mercu BuanaJakarta11650Indonesia

Satellite networks are recognized as the most essential communication infrastructures in the world today,which complement land networks and provide valuable services for their *** coverage and service stability of these networks have increased their *** eavesdropping and active intrusion in satellite communications are much easier than in terrestrial networks,securing satellite communications is *** far,several protocols have been proposed for authentication and key exchange of satellite communications,but none of them fullymeet the security *** this paper,we examine one of these protocols and identify its security ***,we propose a robust and secure authentication and session key agreement protocol using the elliptic curve cryptography(ECC).We show that the proposed protocol meets common security requirements and is resistant to known security ***,we prove that the proposed scheme satisfies the security features using the Automated Validation of Internet Security Protocols and Applications(AVISPA)formal verification tool and On-the fly Model-Checker(OFMC)and ATtack SEarcher(ATSE)model *** have also proved the security of the session key exchange of our protocol using theReal orRandom(RoR)***,the comparison of our scheme with similar methods shows its superiority.

关键词： Satellite communications authentication session key agreement secure communication security protocols formal verification

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