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Transactions of Nonferrous Metals Society of China 2021年第10期31卷 3177-3191页

作者： Matin GHADIMI REZAEI Pooyan HASHEMI TARI mohammad emamzadeh Leili TAFAGHODI KHAJAVI Mechanical Engineering Department Shahid Beheshti UniversityTehran16589-53571Iran Material Science and Engineering Department McMaster UniversityHamilton L8S 4L7Canada

In molten phase metallurgical processes,mixing via gas injection has a vital role in obtaining a homogeneous *** efficiency of mixing depends on operational variables such as gas flow rate and slag height as well as physical properties of the molten phases.A numerical simulation is conducted to study the above parameters in the flow behavior of a bottom-blown *** molten metal and the slag are modeled by water and oil,*** numerical results,particularly the mixing time,are validated against experimental *** results show that mixing time increases as the slag height increases and decreases as the density of the slag material *** mixing time decreases with an increase in the density of the primary phase;however,it increases as the surface tension between air and water increases.A case with properties close to a real molten metal is also *** performance of the system is influenced by the momentum rather than the dissipative ***,the effect of the density of the molten phase on the mixing process is more pronounced compared to the effect of the surface tension between the air and the molten phase.

关键词： gas-stirred ladle mixing time density surface tension tracer concentration numerical simulation

Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： Khalil Ullah Song Jian Muhammad Naeem Ul Hassan Suliman Khan mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

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

Determining an optimum pattern of mixed planting from organic and non-organic crops with regard to economic and environmental indicators:A case study of cucumber in Kerman,Iran

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Information Processing in Agriculture 2016年第4期3卷 207-214页

作者： Soraya Molaie emamzadeh mohammad Ali Forghani Assadollah Karnema Samaneh Darbandi Shahid Bahonar University of Kerman Iran Managment Department Shahid Bahonar University of KermanIran

Today,planning procedures which are used in different fields of decision making such as determination of optimum planting patterns are considered as important management *** importance of optimum planting patterns is highlighted when we learn that agricultural measures may have environmental side *** economical analyses only focus on increasing economic gains of the farmers without regard to its environmental ***,one can argue that efficient managers should consider multiple purposes that cover both economic and environmental goals at the same *** study attempted to identify an optimum mixed model of organic and non-organic production systems using a combination of AHP(Analytical Hierarchy Process)approach andWeighted Goal Programming to consider environmental and economic indicators *** procedure was employed in the current design to determine and compare an optimum pattern of mixed planting of organic and non-organic *** study sample was cucumber,investigated in four farming systems:organic open field farming system,nonorganic greenhouse farming system,non-organic tunnel farming system and open field non-organic farming system in Jiroft,Kerman,with regard to paper *** the proposed MCDM(Multiple Criteria Decision Making)model,cucumber planting in open field non-organic farming system was replaced by open field organic farming *** and environmental indicators rose by 11.97%and 21.40%respectively in MCDM proposed plan in comparison with the existing farm plan,which indicates the feasibility of MCDM proposed plan in terms of economic and environmental indicators.

关键词： Organic agriculture AHP Weighted Goal Programming

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

Dynamic Adaptive Finite Element Analysis of Acoustic Wave Propagation Due to Underwater Explosion for Fluid-structure Interaction Problems

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Journal of Marine Science and Application 2015年第3期14卷 302-315页

作者： Seyed Shahab emamzadeh mohammad Taghi Ahmadi Soheil mohammadi Masoud Biglarkhani Islamic Azad University Kangan Branch Kangan *** Iran Department of Civil Engineering Tarbiat Modares University Tehran 14115-143 Iran School of Civil Engineering University of Tehran Tehran 4563-11155 Iran Department of Civil Engineering University of Hormozgan Hormozgan 3995 Iran

In this paper, an investigation into the propagation of far field explosion waves in water and their effects on nearby structures are carried out. For the far field structure, the motion of the fluid surrounding the structure may be assumed small, allowing linearization of the governing fluid equations. A complete analysis of the problem must involve simultaneous solution of the dynamic response of the structure and the propagation of explosion wave in the surrounding fluid. In this study, a dynamic adaptive finite element procedure is proposed. Its application to the solution of a 2D fluid-structure interaction is investigated in the time domain. The research includes：a） calculation of the far-field scatter wave due to underwater explosion including solution of the time-depended acoustic wave equation, b） fluid-structure interaction analysis using coupled Euler-Lagrangian approach, and c） adaptive finite element procedures employing error estimates, and re-meshing. The temporal mesh adaptation is achieved by local regeneration of the grid using a time-dependent error indicator based on curvature of pressure function. As a result, the overall response is better predicted by a moving mesh than an equivalent uniform mesh. In addition, the cost of computation for large problems is reduced while the accuracy is improved.

关键词： adaptive mesh fluid-structure interaction acoustic wave finite element analysis underwater explosion

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

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

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