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Fatigue Reliability Analysis of Fiber-Reinforced Laminated Composites by Continuum Damage Mechanics

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Acta Mechanica Solida Sinica 2023年第3期36卷 469-476页

作者： peyman Gholami Aerospace Research Institute Ministry of ScienceResearch and TechnologyTehranIran

This paper investigates the reliability of composite laminates with various lay-ups under fatigue *** prediction of failure probability of composite laminates subjected to different loads involves many uncertainties associated with mechanical properties,loading,and boundary *** in the composite material is truly hard to trace because there are individual faults in each ply,and we face a stochastic process due to the scatter in the mechanical *** continuum damage mechanics(CDM),as a powerful approach,is applied to model the damage of fiber,matrix,and fiber/matrix *** method defines criteria for damage detection and determines safe *** material constitutive equations are executed using a subroutine *** first-order reliability method and second-order reliability method have been applied to examine the reliability of laminated *** results are compared with those of the Monte Carlo *** composite laminates under different stress levels are considered for the failure probability *** limit state functions and random variables have been determined based on the CDM ***,the effects of the number of cycles,applied stress,and stacking sequence of the laminate on the reliability and fatigue life in fiber-reinforced laminated composites are assessed.

关键词： Composite laminate Continuum damage mechanics Fatigue damage First-order reliability method Second-order reliability method Monte Carlo simulation

A RESULT OF SUZUKI TYPE IN PARTIAL G-METRIC SPACES

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Acta Mathematica Scientia 2014年第2期34卷 274-284页

作者： peyman SALIMI Pasquale VETRO Young Researchers and Elite Club Rasht BranchIslamic Azad University Università degli Studi di Palermo Dipartimento di Matematica e Informatica

Recently, Suzuki [T. Suzuki characterizes metric completeness, Proc. A generalized Banach contractlon principle that Amer. Math. Soc. 136 （2008）, 1861-1869] proved a fixed point theorem that is a generalization of the Banach contraction principle and char- acterizes the metric completeness. Paesano and Vetro [D. Paesano and P. Vetro, Suzuki＇s type characterizations of completeness for partial metric spaces and fixed points for partially ordered metric spaces, Topology Appl., 159 （2012）, 911-920] proved an analogous fixed point result for a self-mapping on a partial metric space that characterizes the partial metric O- completeness. In this article, we introduce the notion of partial G-metric spaces and prove a result of Suzuki type in the setting of partial G-metric spaces. We deduce also a result of common fixed point.

关键词： Fixed and common fixed points Suzuki fixed point theorem partial G-metricspaces

Evolution of seasonal land surface temperature trend in pond-breeding newt(Neurergus derjugini)in western Iran and eastern Iraq

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Ecological Processes 2023年第1期12卷 217-231页

作者： peyman Karami Sajad Tavakoli Mina Esmaeili Department of Environmental Sciences Faculty of Natural Resources and Environment SciencesMalayer UniversityMalayerIran Department of Environmental and Forest Science Faculty of Natural Resources and EnvironmentScience and Research BranchIslamic Azad UniversityTehranIran Department of Biology Faculty of ScienceRazi UniversityKermanshahIran

Background Temperature,as one of the effective environmental stimuli in many aspects of species life and ecosystems,can affect amphibians in many *** and predicting temperature change and its possible effects on the habitat suitability and movements of amphibians have led many researchers to use climate change scenarios and species distribution models(SDMs).One of the important remote-sensing products that received less attention of conservation biologists is the land surface temperature(LST).Due to the small difference between LST and air temperature,this component can be used to investigate and monitor the daily and seasonal changes of *** study aims to investigate the seasonal trend of LST in the habitat suitability and connectivity of the critically endangered newt(Neurergus derjugini)in its small distribution range,using the MODIS LST time series(2003 to 2021)and with the help of SDMs,Mann–Kendall(MK)and Pettitt non-parametric *** In the last decade,the increasing trend of LST versus its decreasing trends is *** on MK and Pettitt tests,in the winter and spring,with the decrease in latitude of 35.45°and increase in longitude of 46.14°,the core populations which are located in the southeast have experienced an increase in *** the period time of breeding and overwintering,the continuity of winter and spring can be effective on the survival of adult newts as well as larvae in the *** with the highest current flow between core populations in the winter and summer are the most likely to be *** the level of habitat,the increase in LST is proportional to the trend of thermal landscape changes,and all seasons have had an increase in LST,but in winter and summer,the largest area of the habitat has been *** continuing the current trend,many high-altitude southern habitats in Iran will be endangered,and the species will be at risk of local *** The increasing tre

关键词： Seasonal change Local extinction Climate refuge Amphibian

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A Facile Method for Dye and Heavy Metal Elimination by p H Sensitive Acid Activated Montmorillonite/Polyethersulfone Nanocomposite Membrane

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Chinese Journal of Polymer Science 2018年第1期36卷 49-57页

作者： Mehdi Mahmoudian peyman Gozali Balkanloo Ehsan Nozad Nanotechnology Research Institute Urmia University

Modified clay/polyethersulfone（PES） mixed matrix membranes（MMMs） were prepared by acid activated montmorillonite（AA-MMT） with different concentrations and used to eliminate dyes and remove heavy metals from aqueous solution. The morphology and physiochemical properties of prepared clay nanoparticles and MMMs were characterized using X-ray diffraction（XRD）, Fourier transform infrared（FTIR） spectroscopy, scanning electron microscopy（SEM）, enegy dispersive X-ray（EDX） spectroscopy, Brunauer-Emmett-Teller（BET） analysis, atomic force microscopy（AFM）, contact angle measurement and fouling studies. The filtration study showed that removal of dyes and heavy metals was strongly dependent on p H so that dyes with positive and negative charges showed different separation efficiency in acidic and alkaline conditions. The modified membranes possessed better heavy metal removal in acidic and alkaline p Hs. When the rejection of heavy metals was measured in an alkaline environment, it was observed that the rejection had a great increase compared to the neutral values for Zn^（2＋） and Ni^（2＋） ions, while rejection of Cu^（2＋） and Cd^（2＋） did not undergo significant changes. So it can be concluded that modified membranes show good selectivity for elimination of Zn^（2＋） and Ni^（2＋） ions with respect to other cations.

关键词： Nanocomposite membranes Acid activated montmorillonite Heavy metal/dye elimination

Shape factor for regular and irregular matrix blocks in fractured porous media

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Petroleum Science 2020年第1期17卷 136-152页

作者： peyman Rostami Mohammad Sharifi Morteza Dejam Department of Petroleum Engineering Amirkabir University of Technology(Polytechnic of Tehran)Hafez AvenueP.O.Box 15875-4413TehranIran Department of Petroleum Engineering College of Engineering and Applied ScienceUniversity of Wyoming1000 E.University AvenueLaramieWY 82071-2000USA

Describing matrix–fracture interaction is one of the most important factors for modeling natural fractured reservoirs.A common approach for simulation of naturally fractured reservoirs is dual-porosity modeling where the degree of communication between the low-permeability medium(matrix)and high-permeability medium(fracture)is usually determined by a transfer *** of the proposed matrix–fracture functions depend on the geometry of the matrix and fractures that are lumped to a factor called shape ***,there is no unique solution for calculating the shape factor even for symmetric *** fine-scale modeling is a tool for calculating the shape factor and validating the current solutions in the *** this study,the shape factor is calculated based on the numerical simulation of fine-grid simulations for single-phase flow using finite element *** the best of the author’s knowledge,this is the first study to calculate the shape factors for multidimensional irregular bodies in a systematic *** models were used,and shape factors were calculated for both transient and pseudo-steady-state(PSS)cases,although in some cases they were not clarified and assumptions were not *** boundary condition dependency of the shape factor was also investigated,and the obtained results were compared with the results of other *** show that some of the most popular formulas cannot capture the exact physics of matrix–fracture *** obtained results also show that both PSS and transient approaches for describing matrix–fracture transfer lead to constant shape factors that are not unique and depend on the fracture pressure(boundary condition)and how it changes with time.

关键词： Fractured reservoirs Shape factor Matrix–fracture boundary conditions Computational fluid dynamic(CFD)

A Machine Learning Approach for Collusion Detection in Electricity Markets Based on Nash Equilibrium Theory

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Journal of Modern Power Systems and Clean Energy 2021年第1期9卷 170-180页

作者： peyman Razmi Majid Oloomi Buygi Mohammad Esmalifalak the Department of Electrical Engineering Ferdowsi University of MashhadMashhadIran the Predictive Modeling Department of Fiix Software TorontoCanada

We aim to provide a tool for independent system operators to detect the collusion and identify the colluding firms by using day-ahead data. In this paper, an approach based on supervised machine learning is presented for collusion detection in electricity markets. The possible scenarios of the collusion among generation firms are firstly identified. Then,for each scenario and possible load demand, market equilibrium is computed. Market equilibrium points under different collusions and their peripheral points are used to train the collusion detection machine using supervised learning approaches such as classification and regression tree(CART) and support vector machine(SVM) algorithms. By applying the proposed approach to a four-firm and ten-generator test system, the accuracy of the proposed approach is evaluated and the efficiency of SVM and CART algorithms in collusion detection are compared with other supervised learning and statistical techniques.

关键词： Market power collusion detection machine learning support vector machine(SVM) classification and regression tree(CART) statistical method

Active Control of A Piston-Type Absorbing Wavemaker with Fully Reflective Structure

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China Ocean Engineering 2020年第5期34卷 730-737页

作者： Saeed MAHJOURI Rasoul SHABANI Ghader REZAZADEH peyman BADIEI Department of Mechanical Engineering Faculty of EngineeringUrmia UniversityUrmiaIran South Ural state University ChelyabinskRussian Federation cDepartment of Civil Engineering Tehran UniversityTehranIran

Multiple reflections of the waves between structure and wavemaker in hydraulic flumes could change the frequency content of the desired incident wave or result in resonance. A prominent approach to avoid multiple reflections is active control of the wavemaker. This paper proposes a simple and practical active control algorithm for piston-type wavemaker. The block diagram of the control system is presented in real time domain. It is shown that there is no need to use any transfer function or filter in the feedback and feed forward loops and the use of constant gains can yield acceptable results. In the operating frequency range(0.25-2 Hz), it is revealed that the proposed system is very effective at suppressing the excitation of resonant sloshing for regular wave. In the case of irregular waves, it is depicted that the experimental waves agree quite well with the desired wave elevation in frequency domain. In addition, comparison of the results obtained both with and without absorption discloses the good characteristics in time domain.

关键词： wave flume piston-type wavemaker active absorption mathematical modeling reflective waves

Practical seismic resilience evaluation and crisis management planning through GIS-based vulnerability assessment of buildings

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Earthquake Engineering and Engineering Vibration 2021年第1期20卷 25-37页

作者： peyman Narjabadifam Ramin Hoseinpour Mohammad Noori Wael Altabey Department of Civil Engineering Faculty of EngineeringUniversity of Bonab***BonabIran Department of Mechanical Engineering California Polytechnic State UniversitySan Luis ObispoCA 93405USA International Institute for Urban Systems Engineering(IIUSE) Southeast UniversityNanjing 210096China Department of Mechanical Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt

The objective of this paper is to demonstrate how assessment of seismic vulnerability can be effective in protection against *** are reported from a case study in a densely populated urban area near an active fault,utilizing practical methods and exact engineering *** factors were determined due to technical considerations,and a field campaign was performed to collect the required ***-criteria decision making was carried out by means of an analytical hierarchy process including a fuzzy *** scenarios were applied through an implicit vulnerability *** was utilized and the results were analyzed by classifying the state of vulnerability in levels as very low,low,moderate,high,and very *** resilience was evaluated as vulnerabilities below the moderate state,being about 40% in an intensity of 6 Mercalli and less than 10% in 10 *** is concluded that seismic resilience in the area studied is not acceptable,the area is vulnerable in the expected scenarios,and due to the high seismicity of the region,proper crisis management planning is required in parallel with attempts toward *** this regard,an emergency map was developed with reference to the assessed vulnerabilities.

关键词： seismic resilience crisis management vulnerability assessment earthquake retrofit AHP Expert Choice GIS

Performance enhancement of cantilever piezoelectric energy harvesters by sizing analysis

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International Journal of Smart and Nano Materials 2020年第2期11卷 93-116页

作者： peyman Hajheidari Ion Stiharu Rama Bhat Department of Mechanical Industrial and Aerospace Engineering(MIAE)University of ConcordiaMontrealQuébecCanada

This paper presents the results of the performance of piezoelectric cantilever beams in relation to their *** total produced power represents the main indicator of performance of a piezoelectric harvesting system while the area of the beams stays *** design is an important aspect in any industry,mainly in the *** this study,the effects of non-uniformity on the efficiency and power output are *** element method(FEM)with the application of superconvergent element(SCE)is adopted here to solve the *** is observed that the trapezoidal geometry(converging beam)provides a higher output power while the efficiency ***,in order to prove that the power enhancement is achievable while the amount of piezoelectric material consumed is constant the new configuration is *** the configuration,an array of uniform beams connected in series is used instead of one single rectangular *** proposed setting generates an output power of 1.817mWat a resonant frequency of 284.6 Hz when excited by an input acceleration of 1 *** only challenge is the fundamental frequency difference which ismet with the application of proof mass and thinner substrate and piezoelectric layers.

关键词： Piezoelectric energy harvester superconvergent element tapered beam performance enhancement sizing