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Defence Technology（防务技术） 2021年第1期17卷 177-184页

作者： Maziyar Bazmaraa mohammad silani Iman Dayyani Department of Mechanical Engineering University of HoustonTX 77204United States Centre for Structures Assembly and Intelligent AutomationCranfield UniversityCranfieldBedford MK430ALUnited Kingdom Department of Mechanical Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

In nanocomposites,the interphase thickness may be comparable to the size of nano-particles,and hence,the effect of interphase layers on the mechanical properties of nanocomposites may be *** interphase thickness to the nano-particle size ratio and properties variability across the interphase thickness are the most important affecting parameters on the overall behavior of *** this study,the effect of properties variability across the interphase thickness on the overall elastic and elastoplastic properties of a polymeric clay nanocomposite(PCN)using a functionally graded(FG)interphase is investigated in *** results of the computational homogenization on the mesoscopic level show that Young’s modulus variation of the interphase has a significant effect on the overall elastic response of nanocomposites in a higher clay weight ratio(Wt).Moreover,strength variation through the interphase has a notable effect on the elasto-plastic properties of ***,the increase or decrease in stiffness of interphase from clay to matrix and vice versa have a similar effect in the overall behavior of nanocomposites.

关键词： Nylon 6/clay nanocomposites FG Interphase Computational homogenization

Micromechanical simulation and experimental investigation of aluminum-based nanocomposites

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Defence Technology（防务技术） 2021年第1期17卷 196-201页

作者： mohammad Javad Ghasemi mohammad silani Ali Maleki Mostafa Jamshidian Department of Mechanical Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

Ceramic reinforced metal matrix nanocomposites are widely used in aerospace and auto industries due to their enhanced mechanical and physical *** this research,we investigate the mechanical properties of aluminum/Nano-silica composites through experiments and ***/Nanosilica composite samples with different weight percentages of silica nanoparticles are prepared via powder *** this method,Nano-silica and aluminum powders are mixed and compressed in a mold,followed by sintering at high *** tensile testing of the nanocomposite samples shows that adding one percent of Nano-silica causes a considerable increase in mechanical properties of nanocomposite compared to pure aluminum.A computational micromechanical model,based on a representative volume element of aluminum/silica nanocomposite,is developed in a commercial finite element *** model employs an elastoplastic material model along with a ductile damage model for aluminum matrix and linear elastic model for nano-silica *** careful determination of model parameters from the experimental results of pure aluminum samples prepared by powder metallurgy,the proposed computational model has shown satisfactory agreement with *** validated computational model can be used to perform a parametric study to optimize the microstructure of nanocomposite for enhanced mechanical properties.

关键词： Aluminum/nano-silica composites Powder metallurgy Micromechanics

基于物理信息的神经网络方法在梁非线性屈曲分析中的应用

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Acta Mechanica Sinica 2023年第6期39卷 80-92页

作者： Maziyar Bazmara mohammad Mianroodi mohammad silani Department of Mechanical Engineering University of HoustonHouston 77204USA University of Strasbourg 67000 StrasbourgCNRSFrance Department of Mechanical Engineering Isfahan University of Technology84156-83111 IsfahanIran

本文提出了一种基于物理信息的神经网络(PINN)框架来分析在Winkler-Pasternak基础上的三维功能梯度FG多孔细长梁的非线性屈曲行为.使用简单的网络,PINNs只需要很少的训练数据来获得较高的精度.在这项工作中使用的强大工具可以处理任何... 详细信息

本文提出了一种基于物理信息的神经网络(PINN)框架来分析在Winkler-Pasternak基础上的三维功能梯度FG多孔细长梁的非线性屈曲行为.使用简单的网络,PINNs只需要很少的训练数据来获得较高的精度.在这项工作中使用的强大工具可以处理任何类型的偏微分方程.我们使用深度学习平台TensorFlow和DeepXDE库来设计我们的网络.在本研究中,PINNs框架从梁系统的控制微分方程和边界条件中获取信息,并输出临界非线性屈曲载荷.利用哈密顿原理,考虑几何的非线性,建立了数学模型.通过将建模框架应用于各种边界条件情况以及三维功能梯度FG指标等物理参数对非线性力学行为的影响,仔细检验了建模框架的准确性.最后,利用广义微分求积法(GDQM)对PINNs结果进行了验证.研究结果表明,所提出的PINN框架能够较好地表征三维功能梯度FG多孔细长梁的非线性屈曲行为.此外,PINN预测梁的非线性屈曲行为的速度比数值方法快71倍.

关键词：非线性屈曲深度学习广义微分求积法物理信息哈密顿原理非线性力学行为建模框架三维功能

Risk factors for congenital nasolacrimal duct obstruction in children under two years of age

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国际眼科杂志 2025年第1期25卷 17-23页

作者： Rozhin Kasiri Gholamreza Khataminia Ali Kasiri mohammad Sadegh Mirdehghan mohammad Armin Kasiri Infectious Ophthalmologic Research Center Ahvaz Jundishapur University of Medical SciencesAhvaz ***Iran Islamic Azad University Tehran Medical Sciences Tehran ***Iran

·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for *** was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes ***,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis.

关键词： risk factors congenital nasolacrimal duct obstruction children

Decoding molecular mechanisms:brain aging and Alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay Ali Syed Hammad Qaiser mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir Atta-ur-Rahman School of Applied Biosciences(ASAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological Sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

关键词： Alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Resilience-oriented intentional islanding of reconfigurable distribution power systems

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 741-752页

作者： mohammad Hossein OBOUDI mohammad mohammadI mohammad RASTEGAR Department of Power and Control Engineering School of Electrical and Computer EngineeringShiraz UniversityShirazIran

The participation of distributed energy resources in the load restoration procedure,known as intentional islanding,can significantly improve the distribution system *** system reconfiguration can effectively alter islanding procedure and thus provide an opportunity to supply more demanded energy and reduce distribution system *** addition,high-impact events such as hurricanes and earthquakes may complicate the procedure of load restoration,due to the disconnection of the distribution system from the upstream grid or concurrent component *** paper presents a two-level method for intentional islanding of a reconfigurable distribution system,considering high-impact *** thefirst level,optimal islands are selected according to the graph model of the distribution *** the second level,an optimal power flow(OPF)problem is solved to meet the operation constraints of the islands by reactive power control and demand side *** proposed problem in the first level is solved by a combination of depth first search and particle swarm optimization *** OPF problem in the second level is solved in DIgSILENT *** proposed method is implemented in the IEEE 69-bus test system,and the results show the validity and effectiveness of the proposed algorithm.

关键词： Intentional islanding Active distribution system Distributed energy resource Distribution system reconfiguration Distribution system resilience

Global Practical Stabilization of Discrete-Time Switched Affine Systems via a General Quadratic Lyapunov Function and a Decentralized Ellipsoid

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1837-1851页

作者： mohammad Hejri Department of Electrical Engineering Sahand University of TechnologySahand New TownTabriz 51335-1996Iran

This paper addresses the problem of global practical stabilization of discrete-time switched affine systems via statedependent switching *** attempts have been made to solve this problem via different types of a common quadratic Lyapunov function and an *** classical results require either the quadratic Lyapunov function or the employed ellipsoid to be of the centralized *** some cases,the ellipsoids are defined dependently as the level sets of a decentralized Lyapunov *** this paper,we extend the existing results by the simultaneous use of a general decentralized Lyapunov function and a decentralized ellipsoid parameterized *** proposed conditions provide less conservative results than existing works in the sense of the ultimate invariant set of attraction *** different approaches are proposed to extract the ultimate invariant set of attraction with a minimum size,i.e.,a purely numerical method and a numerical-analytical *** the former,both invariant and attractiveness conditions are imposed to extract the final set of matrix *** latter is established on a principle that the attractiveness of a set implies its ***,the stability conditions are derived based on only the attractiveness property as a set of matrix inequalities with a smaller *** examples are presented to prove the satisfactory operation of the proposed stabilization methods.

关键词： Decentralized quadratic Lyapunov function decentralized ellipsoid discrete-time switched affine systems practical stabilization switching power converters

Stabilizing silica nanoparticles in high saline water by using polyvinylpyrrolidone for reduction of asphaltene precipitation damage under dynamic condition

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Chinese Journal of Chemical Engineering 2019年第5期27卷 1021-1029页

作者： mohammad Reza Aghajanzadeh mohammad Sharifi Department of Petroleum Engineering Amirkabir University of Technology

In this study, the performance of stable nanofluid containing SiO2 nanoparticles dispersed and stabilized in high salinity brine for asphaltene inhibition in dynamic condition is evaluated. In the first stage of this work, the stability of silica nanoparticles in different range of water salinity(0–100000 mg·L-1) is investigated. Next, stable nanofluid containing highest salinity is selected as asphaltene inhibitor agent to inject into the damaged core sample. The estimated values of oil recovery for base case, after damage process and after inhibition of asphaltene precipitation using nanofluid are 51.6%, 36.1% and 46.7%, respectively. The results showed the reduction in core damage after using nanofluid. In addition, the relative permeability curves are plotted for the base case, after damage process and also after inhibition of asphaltene precipitation using nanofluid. Comparison of relative permeability curves shows, relative permeability of oil phase decreased after damage process as compared with the base case. But after using nanofluid the oil relative permeability curve has shifted to the right and effective permeability of oil phase has been improved.

关键词： Formation damage Enhanced oil recovery Salinity Asphaltene Core flooding Nano particles

Nonlinear analysis of cable structures using the dynamic relaxation method

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Frontiers of Structural and Civil Engineering 2021年第1期15卷 253-274页

作者： mohammad REZAIEE-PAJAND mohammad mohammadI-KHATAMI Department of Civil Engineering Ferdowsi University of MashhadMashhad ***Iran

The analysis of cable structures is one of the most challenging problems for civil and mechanical *** they have highly nonlinear behavior,it is difficult to find solutions to these *** far,different assumptions and methods have been proposed to solve such *** dynamic relaxation method(DRM)is an explicit procedure for analyzing these types of *** utilize this scheme,investigators have suggested various stiffness matrices for a cable *** this study,the efficiency and suitability of six well-known proposed matrices are assessed using the *** achieve this goal,16 numerical examples and two criteria,namely,the number of iterations and the analysis time,are *** on a comprehensive comparison,the methods are ranked according to the two *** numerical findings clearly reveal the best ***,a variety of benchmark problems are suggested by the authors for future studies of cable structures.

关键词： nonlinear analysis cable structure stiffness matrix dynamic relaxation method

DEM Numerical Simulation of Abrasive Wear Characteristics of a Bioinspired Ridged Surface

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Journal of Bionic Engineering 2010年第2期7卷 175-181页

作者： mohammad Almagzoub mohammad Carlo Menon Key Laboratory of Bionic Engineering Jilin University College of Biological and Agricultural Engineering Jilin University MENRVA Group Simon Fraser University

This paper presents numerical investigations into a ridged surface whose design is inspired by the geometry of a Farrer’*** objective of the performed research is to assess if the proposed Bioinspired Ridged Surface (BRS) can potentiallyimprove wear resistance of soil-engaging components used in agricultural machinery and to validate numerical simulationsperformed using software based on the Discrete Element Method (DEM).The wear performance of the BRS is experimentallydetermined and also compared with a conventional flat *** size of soil particles and relative velocities between theabrasive sand and the testing surfaces are *** results show that the numerical simulations are in agreement withthe experimental results and support the hypothesis that abrasive wear is greatly reduced by substituting a conventional flatsurface with the BRS.

关键词： bioinspired ridged surface abrasive wear numerical simulation Discrete Element Method (DEM)