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Free Vibration Analysis of Functionally Graded Plates with Multiple Circular and Non-circular Cutouts

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Chinese Journal of Mechanical Engineering 2012年第2期25卷 277-284页

作者： JANGHORBAN maziar ROSTAMSOWLAT Iman Department of Mechanical Engineering Shiraz BranchIslamic Azad UniversityShirazIran

Cutouts are inevitable in structures due to practical *** order to investigate the free vibration of functionally graded plates with multiple circular and non-circular cutouts,finite element method is *** volume fraction of the material constituents is assumed to follow a simple power law *** parameters considered in this paper are as follows：cutout size,cutout location,number of cutouts and different boundary *** should be mentioned that free vibration for FG plates（such as rectangular？skew？trapezoidal？circular plates） with multiple cutouts has not been studied yet and hence the results out coming from this paper may be used as bench marks for future works.

关键词： graded materials rectangular?skew?trapezoidal?circular plates multiple circular/non-circular cutouts

Passive energy storage using distributed electric loads with thermal storage

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Journal of Modern Power Systems and Clean Energy 2013年第3期1卷 264-274页

作者： Ning LU maziar VANOUNI Electrical and Computer Engineering Department North Carolina State UniversityRaleighNCUSA

This paper presents the concept of controlling distributed electric loads with thermal energy storage as a passive electric energy storage system(PEESS).Examples of such loads include different types of thermostatically controlled appliances(TCAs)such as hot water heaters,air conditioners,and *** TCA can be viewed as a thermal cell that stores electricity as thermal energy.A centralized control mechanism can be used to control the timing of each thermal cell to consume electric energy so that the aggregated electricity consumption of the thermal cells will vary against a baseline ***,when the aggregated consumption is higher than the baseline,the PEESS is charging;otherwise,the PEESS is *** overall performance of a PEESS will be equivalent to that of a battery energy storage *** paper presents the configuration and formulates the control of a *** modeling results demonstrate the feasibility of implementing the PEESS.

关键词： Energy storage Demand response Load management Thermostatically controlled appliances Distributed control Smart grid

Evaluation of the pull-out strength of galvanised steel strips in a cement-based material

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 843-855页

作者： maziar RAMEZANI Juan VILCHES Thomas NEITZERT Centre for Advanced Manufacturing Technology (CAMTEC) School of Engineering Auckland University of Technology

The study of the interfacial and bond behaviour of reinforced cement-based materials is important for understanding the mechanical behaviour of such *** paper presents extensive experimental,theoretical and finite element analyses of pull-out tests of galvanised steel strips with different geometries,in lightweight cement-based material blocks with different densities and mechanical *** theoretical model proposed here is capable of determining the pull-out strength and bond stress versus the slip relationship between components of reinforced cement-based *** bond-slip relationship is then implemented in finite element simulation through the user-defined subroutine of ABAQUS *** on the results,a trilinear bond-slip model is suitable for modelling the interface between a steel strip and a cement-based material interface.

关键词： Bond-slip relationship Cement-based materials Galvanised steel strip Pull-out test

Soil-Structure Interaction Analysis of Jack-up Platforms Subjected to Monochrome and Irregular Waves

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China Ocean Engineering 2015年第1期29卷 65-80页

作者： maziar Gholami KORZANI Ali Akbar AGHAKOUCHAK Faculty of Civil and Environmental Engineering Tarbiat Modares University

As jack-up platforms have recently been used in deeper and harsher waters, there has been an increasing demand to understand their behaviour more accurately to develop more sophisticated analysis techniques. One of the areas of significant development has been the modelling of spudean performance, where the load-displacement behaviour of the foundation is required to be included in any numerical model of the structure. In this study, beam on nonlinear winkler foundation （BNWF） modeling--which is based on using nonlinear springs and dampers instead of a continuum soil media--is employed for this purpose. A regular monochrome design wave and an irregular wave representing a design sea state are applied to the platform as lateral loading. By using the BNWF model and assuming a granular soil under spudcans, properties such as soil nonlinear behaviour near the structure, contact phenomena at the interface of soil and spudcan （such as uplifting and rocking）, and geometrical nonlinear behaviour of the structure are studied. Results of this study show that inelastic behaviour of the soil causes an increase in the lateral displacement at the hull elevation and permanent unequal settlement in soil below the spudcans, which are increased by decreasing the friction angle of the sandy soil. In fact, spudeans and the underlying soil cause a relative fixity at the platform support, which changes the dynamic response of the structure compared with the case where the structure is assumed to have a fixed support or pinned support. For simulating this behaviour without explicit modelling of soil-structure interaction （SSI）, moment- rotation curves at the end of platform legs, which are dependent on foundation dimensions and soil characteristics, are obtained. These curves can be used in a simplified model of the platform for considering the relative fixity at the soil- foundation interface.

关键词： jack-up platforms wave loading nonlinear dynamic analysis soil-structure interaction (SS1) beam on nonlinear winkler foundation (BNWF)

Enhancement of grid-connected photovoltaic system using ANFIS-GA under different circumstances

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Frontiers in Energy 2015年第3期9卷 322-334页

作者： Saeed VAFAEI Alireza REZVANI Majid GANDOMKAR maziar IZADBAKHSH Department of Electrical Engineering Saveh Branch Islamic Azad University Saveh Iran

In recent years, many different techniques are applied in order to draw maximum power from photo- voltaic （PV） modules for changing solar irradiance and temperature conditions. Generally, the output power generation of the PV system depends on the intermittent solar insolation, cell temperature, efficiency of the PV panel and its output voltage level. Consequently, it is essential to track the generated power of the PV system and utilize the collected solar energy optimally. The aim of this paper is to simulate and control a grid-connected PV source by using an adaptive neuro-fuzzy inference system （ANFIS） and genetic algorithm （GA） controller. The data are optimized by GA and then, these optimum values are used in network training. The simulation results indicate that the ANFIS-GA controller can meet the need of load easily with less fluctuation around the maximum power point （MPP） and can increase the convergence speed to achieve the MPP rather than the conventional method. Moreover, to control both line voltage and current, a grid side P/Q controller has been applied. A dynamic modeling, control and simulation study of the PV system is performed with the Matlab/Simulink program.

关键词： photovoltaic system maximum power point(MPP) adaptive neuro-fuzzy inference system (ANFIS),genetic algorithm (GA)

Forced Vibration Analysis of Functionally Graded Anisotropic Nanoplates Resting on Winkler/Pasternak-Foundation

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Computers, Materials & Continua 2020年第2期62卷 607-629页

作者： Behrouz Karami maziar Janghorban Timon Rabczuk Department of Mechanical Engineering Marvdasht BranchIslamic Azad UniversityMarvdashtIran Institute of Research and Development Duy Tan UniversityDa NangViet Nam

This study investigates the forced vibration of functionally graded hexagonal nano-size plates for the first time.A quasi-three-dimensional(3D)plate theory including stretching effect is used to model the anisotropic plate as a continuum one where small-scale effects are considered based on nonlocal strain gradient ***,the plate is assumed on a Pasternak foundation in which normal and transverse shear loads are taken into *** governing equations of motion are obtained via the Hamiltonian principles which are solved using analytical based methods by means of Navier’s *** influences of the exponential factor,nonlocal parameter,strain gradient parameter,Pasternak foundation coefficients,length-to-thickness,and length-to-width ratios on the dynamic response of the nanoplates are *** addition,the accuracy of an isotropic approximate instead of the anisotropic model is *** dynamic behavior of the system shows that mechanical mathematics-based models may get better results considering the anisotropic model because the dynamic response can cause prominent differences(up to 17%)between isotropic approximation and anisotropic model.

关键词： Functionally graded materials dynamic deflection nonlocal train gradient theory Winkler-Pasternak elastic foundation

Engineering interfacial band hole extraction on chemical-vapor-deposited MoS 2/CdS core-shell heterojunction photoanode:The junction thickness effects on photoelectrochemical performance

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Journal of Materials Science & Technology 2023年第36期167卷 107-118页

作者： Zhiyuan Peng Yilu Su maziar Jafari Mohamed Siaj Department of Chemistry and Biochemistry Universitédu QuébecàMontréalMontréalQC H3C 3P8Canada

Heterojunction fabrication is a promising strategy that can greatly boost the charge carrier separation and improve the solar-to-hydrogen conversion efficiency of photoelectrochemical(PEC)***,such technology still suffers from limited contact *** this study,the chemical vapor deposition(CVD)technique was for the first time used to construct the CdS/MoS_(2)heterojunction photoanode with a unique core-shell nanoarchitecture,in which a continuous crystalline MoS_(2)nanosheet layer was grown directly on one-dimensional(1D)oriented CdS nanorods(NRs)in a plane-to-plane stacking *** optimization of junction thickness with adjustable MoS_(2)loading from mono to a few layers was achieved by experimental parameters *** characterizations show that the MoS_(2)shell plays a dual role as an optical absorption booster for more photo-exciton generation and a surface passivator of trap ***,the formed heterojunction helps regulate the unidirectional charge migration for a significantly suppressed electron-hole recombination process,which synergistically contributes to higher quantum yield and *** a result,the optimized CdS/MoS_(2)heterojunction photoanode with 3-layered MoS_(2)wrapping exhibits the highest photocurrent density and photoconversion efficiency,over a two-fold increase,compared to those of pristine CdS and the previously reported CdS/MoS_(2)***,due to the rapid hole extraction from CdS and transferred surface oxidation sites,the present CdS/MoS_(2)heterostructure demonstrates better corrosion resistance and higher *** present work is expected to provide a versatile platform for exploiting the CVD technique to develop other MoS_(2)-based heterojunction photoelectrodes with extensive PEC applications.

关键词： Photoelectrochemical Hydrogen evolution Heterojunction fabrication Photoanode Cadmium sulfide Molybdenum sulfide

Spatial distribution and source identification of heavy metals (As, Cr, Cu and Ni) at sub-watershed scale using geographically weighted regression

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International Soil and Water Conservation Research 2019年第3期7卷 308-315页

作者： maziar Mohammadi Abdulvahed Khaledi Darvishan Nader Bahramifar Department of Watershed Managerment Engineering Faculty of Natural ResourcesTarbiat Modares University***Mazandaran Provincelran Department of Environmental Science Faculty of Natural ResourcesTarbiat Modares University***Mazandaran ProvinceIran

Heavy metals are among the most important sources of water and soil *** elements accumulate in the agricultural soil through using contaminated water for irrigation,fertilizers,pesticide and enter to the river systems by water ***,land use plays a serious role in water and sediment *** this regards,geographically weighted regression was used to investigate the spatial correlation between sediment heavy metals and land uses in a highland *** landuse map was used to calculate the area percentage of landuse types in sub-watersheds,followed by geographically weighted regression method to investigate the spatial correlation of As,Cr,Cu and Ni versus three types of land *** highest correlation was observed for irrigated plots versus As and Ni in upstream and for rainfed plots versus AS,Ni and Cr in the *** relationship between heavy metals and developed lands was more complicated and the highest correlation was found for Ni and As at outlet (R2 =0.52-0.89),for Cr in the upstream (R2 =0.50-0.76),and for Cu in the upstream and downstream (R2 =0.36-0.60).The results indicated that there is a positive correlation between heavy metals and land uses which varies with the level of agricultural and urbanization development at *** on the findings,appropriate policies and decisions should be taken on agricultural land to prevent the transfer of heavy metals by sediment to aquatic environments.

关键词： Land use Sediment pollution GWR Talar watershed

Facile synthesis of N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro-1H-pyrolle-2,3-dicarboxylates by one-pot three-component reaction

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Chinese Chemical Letters 2012年第1期23卷 45-48页

作者： Hossein Anaraki-Ardakani maziar Noei Afrooz Tabarzad Department of Chemistry Mahshahr BranchIslamic Azad UniversityMahshahrIran Department of Chemistry Islamic Azad UniversityYazd BranchP.O.Box 89195-155YazdIran

Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-（ary... 详细信息

关键词： Arylsulfonamides Dialkyl acetylenedicarboxylates Triphenylphosphine Multi-component reactions 3-Pyrollin-2-ones