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Earthquake Engineering and Engineering Vibration 2017年第2期16卷 383-395页

作者： Hamid Kazemi Mohsen Ghafory-Ashtiany alireza Azarbakht Department of Civil Engineering Science and Research Branch Islamic Azad University Tehran Iran International Institute of Earthquake Engineering and Seismology (IIEES) Tehran Iran Department of Civil Engineering Faculty of Engineering Arak University Arak Iran

In this study, strong ground motion record （SGMR） selection based on Eta （~/） as a spectral shape indicator has been investigated as applied to steel braced flame structures. A probabilistic seismic hazard disaggregation analysis for the definition of the target Epsilon （ε） and the target Eta （η） values at different hazard levels is presented, taking into account appropriately selected SGMR＇s. Fragility curves are developed for different limit states corresponding to three representative models of typical steel braced frames having significant irregularities in plan, by means of a weighted damage index. The results show that spectral shape indicators have an important effect on the predicted median structural capacities, and also that the parameter r/is a more robust predictor of damage than searching for records with appropriate c values.

关键词： vulnerability spectral shape indicator incremental dynamic analysis damage index hazard disaggregation record selection

Novel Non-monotonic Lyapunov-Krasovskii Based Stability Analysis and Stabilization of Discrete State-delay System

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International Journal of Automation and computing 2020年第5期17卷 713-732页

作者： Younes Solgi alireza Fatehi Ala Shariati APAC Research Group Industrial Control Center of ExcellenceFaculty of Electrical EngineeringK.N.Toosi University of TechnologyTehran ***Iran

This paper proposes a novel less-conservative non-monotonic Lyapunov-Krasovskii stability approach for stability analysis of discrete time-delay *** this method,monotonically decreasing requirements of the Lyapunov-Krasovskii method are replaced with non-monotonic *** Lyapunov-Krasovskii functional is allowed to increase in some steps,but the overall trend should be *** model of practical systems used for stability analysis usually contain ***,firstly a non-monotonic stability condition is derived for certain discrete time-delay systems,then robust non-monotonic stability conditions are proposed for uncertain ***,a novel stabilization algorithm is derived based on the introduced non-monotonic stability *** Lyapunov-Krasovskii functional and the controller are obtained by solving a set of linear matrix inequalities(LMI)or iterative LMI based nonlinear *** proposed theorems are first evaluated by some numerical examples,and then by simulation and implementation on the pH neutralizing process plant.

关键词： Lyapunov-Krasovskii functional discrete state-delay systems non-monotonic Lyapunov function robust stability stabilization

Determinants of Adaptation to Climate Change:A Case Study of Rice Farmers in Western Province,Iran

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Chinese Geographical Science 2022年第1期32卷 110-126页

作者： JAMSHIDI alireza JAMSHIDI Masomeh ABADI Bijan Department of Geography Faculty of Literature and HumanitiesUrmia UniversityUrmia 57561-51818Iran Department of Entrepreneurship and Rural Development Ham UniversityHam 14666-64891Iran Department of Biosystem Mechanics Engineering Faculty of AgricultureUniversity of MaraghehMaragheh 55181-83111Iran

The decisions made by agricultural households to adjust to climate change(CC)in Iran are not well *** study is intended to investigate the influence of perceptions and socioeconomic,institutional features on farmers’adaptation decisions about CC,which constitute the hypothetical statements of the *** undertook a survey of 200 farm householders from 31 villages of Ilam Province,situated in the western Iran,as randomly *** result discloses that the proposed discriminant model matches the dataset well,with a strong effect size of partial eta-squared(η^(2)=0.38).The analysis further signals that adapters are younger and more welleducated than *** are also knowledgeable about CC risks and institutional policy *** adapters have subsidiary work,better access to credit,and have good contacts with expansion agents and *** paper concludes that government authorities should provide farmers with the enriched capabilities and competencies enabling them to adapt to CC.

关键词： climate change(CC) drought adaptation management rice farmers Iran

Novel predictive tool for accurate estimation of packed column size

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Journal of Natural Gas Chemistry 2010年第2期19卷 146-150页

作者： alireza Bahadori Hari B.Vuthaluru Department of Chemical Engineering Curtin University of TechnologyGPO Box U1987PerthWA 6845Australia

Traditionally the majority of fractionation columns in natural gas processing plants were equipped with *** an option to trayed columns is to use *** columns offer a larger surface area per unit volume for mass transfer and the continuous gas to liquid contact throughout the column rather than at specific levels （such as in tray columns）.For process design purposes,it is essential to estimate the pressure drop for enabling the proper operation of packed *** this study,a simple generalized pressure drop correlation （GPDC） which is easier than existing approaches requiring more complicated and longer computations is developed for sizing randomly packed fractionation columns for pressure drops up to 150 mm water per meter of *** correlation can be used to estimate pressure drop for a given loading and column ***,for a given pressure drop the diameter can be *** predictions from the proposed correlation have been compared with reported data and found good agreement with average absolute deviation hovering around 4.9%.The proposed predictive tool is superior owing to its accuracy and clear numerical background,wherein the relevant coefficients can be retuned quickly if new and more accurate data are available in the *** proposed simple-to-use approach can be of immense practical value for the engineers and scientists to have a quick check on the pressure drop in packed columns for a given loading and column *** particular,gas engineers would find the proposed approach can be used very friendly involving no complex expressions with transparent and easy-to-handle calculation steps.

关键词： packed columns packing pressure drop flooding design principles

VIBRATION ANALYSIS OF A BEAM WITH EMBEDDED SHAPE MEMORY ALLOY WIRES

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Acta Mechanica Solida Sinica 2013年第5期26卷 536-550页

作者： Mohammad Mehdi Barzegari Morteza Dardel alireza Fathi Department of Mechanical Engineering Babol University of Technology

In this study, analytical relations for evaluating the exact solution of natural fre- quency and mode shape of beams with embedded shape memory alloy （SMA） wires are presented. Beams are modeled according to Euler-Bernoulli, Timoshenko and third order beam （Reddy） the- ories. A relation is obtained for determining the effect of axial load generated by the recovery action of pre-strained SMA wires. By defining some dimensionless quantities~ the effect of different me- chanical properties on the frequencies and mode shapes of the system are carefully examined. The effect of axial load generated by SMA wires with buckling load and frequency jump is accurately studied.

关键词： shape memory alloy natural frequency mode analysis frequency jump Euler-Bernoulli Timoshenko third order beam buckling

Non-thermal plasma modified growth and differentiation process of Capsicum annuum PP805 Godiva in in vitro conditions

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Plasma Science and Technology 2017年第5期19卷 43-48页

作者： Nasrin SAFARI alireza IRANBAKHSH Zahra ORAGHI ARDEBILI Department of Biology Science and Research Branch Islamic Azad University Tehran Iran Department of Biology Garmsar Branch Islamic Azad University Garmsar Iran Author to whom any correspondence should be addressed.

With the aim of evaluating the possible impacts of cold plasma on the structure and growth pattern of Capsicum annuum, the current study was carried out. The seeds were exposed to an argon-derived plasma（0.84 W cm^（-2） surface power densities） for 0, 1 or 2 minutes. Plasmatreated seeds were grown in the Murashige and Skoog（MS） medium or MS medium supplemented with BA and IAA. The presence of purple stems was recorded in plasma-treated plants grown in the medium supplemented with hormones. The recorded morphological differences were dependent on the exposure time of plasma treatments and/or the presence of hormones in the culture media. Plasma treatment of 1 minute had an improving effect on the shoot and root lengths as well as total leaf area, whereas plasma treatment of 2 minutes had an adverse effect. In contrast to the 1 minute treatment, plasma treatment of 2 minutes significantly impaired growth and hence reduced the total biomass. Alterations in stem diameter and differences in tissue patterns（especially in the vascular system） occurred, and were mainly dependent on the plasma exposure time and/or the presence of hormones. This is a first report on the effects of cold plasma on plant growth in in vitro conditions.

关键词： applied physics cold plasma differentiation nitric oxide growth

Characterization of B site codoped LaFeO_3 nanoparticles prepared via co-precipitation route

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Rare Metals 2018年第3期37卷 181-190页

作者： Seyedeh Behnaz Varandili alireza Babaei Abolghasem Ataie School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran

LaFe（1-x-y）CoxPdyO3 [（x, y） =（0, 0）,（0.40, 0）,（0.38, 0.05）] nanoparticles were synthesized via a co-precipitation route using ammonium hydroxide, sodium hydroxide and ammonium carbonate as the precipitant and calcination at different temperatures to study the compositional driven structural changes in lanthanum *** of X-ray diffraction（XRD） patterns confirms the formation of single-phase perovskite structure and existence of orthorhombic Pnma symmetry for calcined powders. Field emission scanning electron microscope（FESEM） observations show that Pd-doped powders yield finer particles along with narrower particle size distribution compared with LaFeO3 and LaFe（0.6）Co（0.4）O3. Moreover,using ammonia as the precipitant leads to a smaller mean particle size of powders compared to NaOH, as well as significant difference in morphology of the *** analysis reveals that both Co and Pd atoms substitute Fe site in perovskite structure with shifting of phonon modes. Comparing Raman spectra demonstrates the presence of more oxygen vacancies in Pd-doped perovskites. It can be concluded from the results that Pd is successfully incorporated into the perovskite structure by co-precipitation method.

关键词： Perovskites Pd doping Nanoparticles Co-precipitation Raman spectroscopy

Effects of intermediate Ni layer on mechanical properties of Al–Cu layered composites fabricated through cold roll bonding

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 573-583页

作者： Ali Shabani Mohammad Reza Toroghinejad alireza Bagheri Department of Materials Engineering Isfahan University of Technology

Layered composites have attracted considerable interest in the recent literature on metal composites. Their mechanical properties depend on the quality of the bonding provided by the intermediate layers. In this study, we analyzed the mechanical properties and bond strengths provided by the nickel layer with respect to its thickness and nature(either powder or coating). The results suggest that bond strength decreases with an increase in the content of nickel powder. At 0.3 vol% of nickel coating, we found the nature of nickel to be less efficient in terms of bond strength. A different picture arose when the content of nickel was increased and the bond strength increased in nickel coated samples. In addition, the results demonstrate that mechanical properties such as bend strength are strongly dependent on bond strength.

关键词： cold roll bonding Al/Ni/Cu composite mechanical testing metallography

Optical absorption engineering in dispersive band structure of MWCNTs array:design and optimization of total absorber for NIR to MIR regime

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Optoelectronics Letters 2022年第9期18卷 513-518页

作者： Bita Etemadi alireza Mobini Department of Electrical and Computer Engineering Qom University of TechnologyQomIran Department of Electrical and Computer Engineering Islamic Azad University Tehran North BranchTehranIran

In this paper,we design a total infrared(IR)absorber based on a dispersive band structure of two-dimensional(2D)multiwall carbon nanotube(MWCNTs)square array working from near IR(NIR)to mid IR(MIR)*** absorption characteristics have been investigated by the 2D finite-difference time domain(FDTD)method in square lattice photonic crystal(PC)of the multipole Drude-Lorentz model inserted to the dispersive dielectric function of *** photonic band structure and scattering parameters for the wide range of lattice constants from 15 nm to 3500 nm with various filling ratios have been *** results show that for large lattice constant(>2000 nm),the Bragg gap moves to the IR regime and leads to MWCNTs arrays acting as a total *** a structure with lattice constant of 3500 nm and filling factor of 12%,an enhanced absorption coefficient up to 99%is achieved in the range of 0.35 eV(λ=3.5μm)nominated in the MIR ***,the absorption spectrum peak can be tuned in the range of 0.27—0.38 eV(λ=4.59—3.26μm)with a changing filling *** results and methodology can be used to design new MWCNTs based photonic devices for applications like night-vision,thermal detector,and total IR absorbers.

关键词： absorber absorption structure

DRAG REDUCTION IN A TURBULENT CHANNEL FLOW WITH HYDROPHOBIC WALL

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Journal of Hydrodynamics 2012年第3期24卷 458-466页

作者： NOURI Nowrouz Mohammad SEKHAVAT Setareh MOFIDI alireza Department of Mechanical Engineering Iran University of Science and TechnologyTehran Iran

This paper investigates a theoretical prediction of friction drag reduction in turbulent channel flow which is achieved by using superhydrophobic surfaces. The effect of the hydrophobic surface is considered to be a slip boundary condition on the wall, and this new boundary condition is added to Large Eddy Simulation （LES） equations. The predicted drag reduction at Rer= 180 is approximately 30%, which concurs with results obtained from Direct Numerical Simulation （DNS）. An important implication of the present finding is that the near-wall turbulence structures are modified with streamwise slip velocity. In addition, a noticeable effect on the turbulence structure occurs when the slin lenmh is ereater than a certain vahle

关键词： superhydrophobic surface Large Eddy Simulation (LES) drag reduction slip length turbulence structures