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Identification of time-varying system and energy-based optimization of adaptive control in seismically excited structure

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 227-240页

作者： Elham Aghabarari fereidoun amini Pedram Ghaderi Department of Civil Engineering Iran University of Science and TechnologyTehran 16844Iran

The combination of structural health monitoring and vibration control is of great importance to provide components of smart *** synthetic algorithms have been proposed,adaptive control that is compatible with changing conditions still needs to be used,and time-varying systems are required to be simultaneously estimated with the application of adaptive *** this research,the identification of structural time-varying dynamic characteristics and optimized simple adaptive control are ***,reduced variations of physical parameters are estimated online using the multiple forgetting factor recursive least squares(MfRLS)***,the energy from the structural vibration is simultaneously specified to optimize the control force with the identified parameters to be *** is also performed based on the probability density function of the energy under the seismic excitation at any ***,the optimal control force is obtained by the simple adaptive control(SAC)algorithm and energy coefficient.A numerical example and benchmark structure are employed to investigate the efficiency of the proposed *** simulation results revealed the effectiveness of the integrated online identification and optimal adaptive control in systems.

关键词： integrated online identification time-varying systems structural energy multiple forgetting factor recursive least squares optimal simple adaptive control algorithm

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石灰处理粘性土的动态性质

路基工程 1998年第4期 75-82页

作者： K.fahoum M.S.Aggour f.amini 孙增生铁道部科学研究院西北分院

本文在大量程应变和侧限压力条件下确定了经过8％石灰处理的高岭土、钠蒙脱土和钙蒙脱土三种压密粘性土的动态性质。三种土的塑性指数范围是:18到514。经过石灰处理影响并改善了三种土的动态性质。这三种土,随着应变范围的增加周期性正... 详细信息

本文在大量程应变和侧限压力条件下确定了经过8％石灰处理的高岭土、钠蒙脱土和钙蒙脱土三种压密粘性土的动态性质。三种土的塑性指数范围是:18到514。经过石灰处理影响并改善了三种土的动态性质。这三种土,随着应变范围的增加周期性正割剪切模量减小,等量粘滞衰减系数增大。随着石灰含量的增加,钠蒙脱土的剪模量显著增大,等量粘滞衰减系数减小。钙蒙脱土也具有相似的性质。两种蒙脱土之间反应曲线的差异被认为是由于钙蒙脱土中原来就存在钙而造成的。高岭土对石灰处理的特性曲线是比较缓和的。本文提出了处理土相对于未处理土的规范化曲线。这些曲线图为改善粘性土的动态性质所需石灰量的初步估算提供了有益的指导作用。

关键词：粘性土动态性质石灰处理

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Relative(n,k)-Weak Cotorsion Modules

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Algebra Colloquium 2024年第3期31卷 481-498页

作者： Mostafa amini Houda Amzil Driss Bennis Department of Mathematics Faculty of SciencesPayame Noor UniversityTehranIran Department of Mathematics Faculty of Sciences EI Jadida Chouaib Doukkali UniversityMorocco Department of Mathematics Faculty of Sciences Mohammed V University in RabatMorocco

Let R be a ring and n,k be two non-negative *** an extension of several known notions,we introduce and study(n,k)-weak cotorsion modules using the class of right R-modules with n-weak fat dimensions at most *** exampl... 详细信息

关键词： (n,k)-weak cotorsion module n-weak injective module n-weak fat module n-super finitely presented module

Improvement of Surface Mechanical and Tribological Characteristics of L-PBf Processed Commercially Pure Titanium through Ultrasonic Impact Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1034-1046页

作者： Iman Ansarian Reza Taghiabadi Saeid amini Mohammad Hossein Mosallanejad Luca Iuliano Abdollah Saboori Department of Materials Science and Metallurgy Imam Khomeini International University(IKIU)QazvinIran Department of Mechanical Engineering University of KashanKashanIran Integrated Additive Manufacturing Center Department of Management and Production EngineeringPolitecnico di TorinoCorso Duca Degli Abruzzi 2410129TurinItaly

Multi-pass ultrasonic impact treatment(UIT)was applied to modify the microstructure and improve the mechanical and tribological characteristics at the near-surface region of commercially pure Ti(CP-Ti)specimens produced by the laser powder bed fusion(L-PBf)*** considerably refined the L-PBf process-related acicular martensites(α′-M)and produced a well-homogenized and dense surface microstructure,where the porosity content of 1-,3-,and 5-pass UITed samples was reduced by 43,60,and 67%,*** UITed samples showed an enhancement in their near-surface mechanical properties up to a depth of about 300μ*** nanoindentation results for the 3-pass UITed sample revealed an increase of about 53,45,and 220%in its nanohardness,H/E_(r),and H_(3)/E_(r)^(2)indices,*** stylus profilometry results showed that performing the UIT removed the L-PBf-related features/defects and offered a smooth *** roughness average(R_(a))and the skewness(R_(sk))of the 3-pass UITed sample were found to be lower than those of the L-PBfed sample by 95 and 223%,*** the UIT also enhanced the material ratio,where the maximum load-bearing capacity(~100%)in as-L-PBfed(as-built)and 3-pass UITed samples was obtained at 60-and 10-µm depths,*** tribological investigations showed that applying the UIT resulted in a significant reduction of wear rate and average coefficient of friction(COf)of *** instance,under the normal pressures of 0.05 and 0.2 MPa,the wear rate and COf of the 3-pass UITed sample were lower than those of the L-PBfed sample by 65 and 58%,and 20 and 17%,respectively.

关键词： Laser powder bed fusion Ultrasonic impact treatment Commercially pure Ti(CP-Ti) Surface mechanical properties Tribological properties

APPROXIMATELY ARTINIAN （NOETHERIAN） C*-ALGEBRAS

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Acta Mathematica Scientia 2024年第6期44卷 2485-2497页

作者： Mohammad ROUZBEHANI Massoud amini Mohammad B.ASADI School of Mathematics Statistics and Computer ScienceCollege of ScienceUniversity of Tehran Department of Mathematics Faculty of Mathematical SciencesTarbiat Modares University School of Mathematics Institute for Research in Fundamental Sciences (IPM)

In this article,we introduce and study the class of approximately Artinian（Noetherian） C*-algebras,called AR-algebras（AN-algebras）,which is a simultaneous generalization of Artinian（Noetherian） C*-algebras and *** study properties such as the ideal property and topological dimension zero for *** particular,we show that a faithful AR or AN algebra is strongly purely infinite iff it is purely infinite iff it is weakly purely *** extends the Kirchberg's O∞-absorption theorem,and implies that a weakly purely infinite C*-algebra is Noetherian iff every its ideal has a full projection.

关键词： (weakly) purely infinite 46L05 46L80 Artinian C*-algebra graph C*-algebra ideal property inductive limit Noetherian

Effectiveness of aromatherapy with lavender compared to progressive muscle relaxation on anxiety and vital signs in patients under spinal anesthesia:A randomized clinical trial

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Journal of Integrative Nursing 2024年第2期6卷 90-95页

作者： Nazanin amini Safoora OMIDVAR Masoomeh Noruzi ZAMENJANI Mehdi HARORANI Hesameddin MODIR Department of Paramedicine Arak University of Medical SciencesArakIran Department of Nursing Shazand School of NursingArak University of Medical SciencesArakIran Department of Anesthesiology Arak University of Medical SciencesArakIran

Objective:This study aimed to determine the effectiveness of aromatherapy with lavender essential oil compared to progressive muscle relaxation(PMR)on anxiety and vital signs of patients under spinal *** and Methods:This clinical trial was conducted on 120 spinal anesthesia candidates who were randomly assigned into three groups of 40 including control,PMR(Jacobsen group),and *** state-trait anxiety inventory was completed on surgery day and 15 min after the end of the intervention by the samples of all three groups,and at the same time as completing the questionnaire,vital signs were also measured and ***:The mean score of anxiety after intervention was lower than that before the intervention in the aromatherapy group(Pf anxiety in the aromatherapy group was significantly lower than that in the Jacobsen group(Pficant decrease in the mean arterial blood pressure scores of the PMR(P=008)and aromatherapy(Pficant increase in the mean heart rate scores in the control group(P=0.002).Conclusion:The use of aromatherapy with lavender is more effective than PMR therapy in reducing the anxiety level of patients undergoing spinal *** to the high level of anxiety and its serious effects on the patient’s hemodynamics,aromatherapy with lavender can be used as an easy and cheap method to reduce anxiety in operation rooms.

关键词： Anxiety aromatherapy lavender essential oil massage progressive muscle relaxation spinal anesthesia vital signs

Elasto-inertial focusing and particle migration in high aspect ratio microchannels for highthroughput separation

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Microsystems & Nanoengineering 2024年第3期10卷 381-394页

作者： Selim Tanriverdi Javier Cruz Shahriar Habibi Kasra amini Martim Costa fredrik Lundell Gustaf Mårtensson Luca Brandt Outi Tammisola Aman Russom Division of Nanobiotechnology Department of Protein ScienceScience for Life LaboratoryKTH Royal Institute of TechnologySolna 17165Sweden Division of Microsystems Technology Department of Materials Science and EngineeringUppsala UniversityUppsala 75237Sweden fLOW and SeRC(Swedish e-Science Research Centre) Department of Engineering MechanicsRoyal Institute of TechnologyStockholm SE 10044Sweden fLOW and fluid Physics Laboratory Department of Engineering MechanicsRoyal Institute of TechnologyStockholmSweden Wallenberg Wood Science Center Royal Institute of TechnologyStockholm SE 10044Sweden Department of Energy and Process Engineering Norwegian University of Science and Technology(NTNU)TrondheimNorway AIMES Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology StockholmSweden

The combination of flow elasticity and inertia has emerged as a viable tool for focusing and manipulating particles using *** there is considerable interest in the field of elasto-inertial microfluidics owing to its potential applications,research on particle focusing has been mostly limited to low Reynolds numbers(Refocusing on the dynamic range of flow rates and particle migration using straight microchannels with a single inlet high aspect *** initially explored several parameters that had an impact on particle focusing,such as the particle size,channel dimensions,concentration of viscoelastic fluid,and flow *** experimental work covered a wide range of dimensionless numbers(0.05focusing could be achieved at Reynolds numbers ranging from 0.2(1μL/min)to 85(250μL/min).furthermore,we numerically and experimentally studied particle migration and reported differential particle migration for high-resolution separations of 5μm,7μm and 10μm particles in a sheathless flow at a throughput of 150μL/*** work elucidates the complex particle transport in elasto-inertial flows and has great potential for the development of high-throughput and high-resolution particle separation for biomedical and environmental applications.

关键词： particle separation straight

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDELAN M.MOHAMMADIMEHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core

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Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman III School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity