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Modeling and Robust Discrete LQ Repetitive Control of Electrically Driven Robots

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International Journal of Automation and computing 2013年第5期10卷 472-480页

作者： Mohammad mehdi Fateh Maryam Baluchzadeh Department of Electrical and Robotic Engineering Shahrood University of Technology

Discrete linear quadratic control has been efciently applied to linear systems as an optimal ***,a robotic system is highly nonlinear,heavily coupled and *** overcome the problem,the robotic system can be modeled as a linear discrete-time time-varying system in performing repetitive *** modeling motivates us to develop an optimal repetitive *** contribution of this paper is *** the frst time,it presents discrete linear quadratic repetitive control for electrically driven robots using the mentioned *** proposed control approach is based on the voltage control ***,uncertainty is efectively compensated by employing a robust time-delay *** uncertainty can include parametric uncertainty,unmodeled dynamics and external *** highlight its ability in overcoming the uncertainty,the dynamic equation of an articulated robot is introduced and used for the simulation,modeling and control *** analysis verifes the proposed control approach and simulation results show its efectiveness.

关键词： Discrete linear quadratic control repetitive control electrically driven robot robust time-delay controller uncertainty

A Precise Robust Fuzzy Control of Robots Using Voltage Control Strategy

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International Journal of Automation and computing 2013年第1期10卷 64-72页

作者： Mohammad mehdi Fateh Sara Fateh Department of Electrical and Robotic Engineering Shahrood University of Technology

Fuzzy control of robot manipulators with a decentralized structure is facing a serious challenge. The state-space model of a robotic system including the robot manipulator and motors is in non-companion form, multivariable, highly nonlinear, and heavily coupled with a variable input gain matrix. Considering the problem, causes and solutions, we use voltage control strategy and convergence analysis to design a novel precise robust fuzzy control （PRFC） approach for electrically driven robot manipulators. The proposed fuzzy controller is Mamdani type and has a decentralized structure with guaranteed stability. In order to obtain a precise response, we regulate a fuzzy rule which governs the origin of the tracking space. The proposed design is verified by stability analysis. Simulations illustrate the superiority of the PRFC over a proprotional derivative like （PD-like） fuzzy controller applied on a selective compliant assembly robot arm （SCARA） driven by permanent magnet DC motors.

关键词： Precise performance fuzzy control robot manipulator voltage control strategy convergence analysis stability analysis

Ce-promoted Mn/Na_2 WO_4/SiO_2 catalyst for oxidative coupling of methane at atmospheric pressure

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Journal of Natural Gas Chemistry 2010年第1期19卷 47-53页

作者： Seyed mehdi Kamali Shahri Ali Nakhaei Pour Research Institute of Petroleum Industry (RIPI) National Iranian Oil Company P. O. Box 18745-4163 Tehran Iran

A series of Ce-promoted Mn-Na2WO4/SiO2 catalysts were prepared by incipient wetness impregnation method, and their catalytic performance for oxidative coupling of methane （OCM） was investigated at atmospheric pressure in a micro-quartz-tube reactor. The catalysts were characterized by X-ray diffraction （XRD）, temperature program reduction （TPR） and BET surface area. Ce promoter increased surface area and Na2WO4 species dispersion, which enriched the amount of the surface species. In addition, Ce promoter increased the Na/W species reduction, but the reduction peak shifted to higher temperature. Stability test of 5wt%Ce catalyst indicated suitable performance and stability. The selectivity and yield of C^2＋ hydrocarbons after 50 h operation reached 65.5% and 19.6%, respectively, at 840 ℃ over 5wt%Ce-2wt%Mn5wt%Na2WO4/SiO2 catalyst.

关键词： oxidative coupling of methane CeO2 promoter Mn/Na2WO4/SiO2

Modelling the Iranian Petroleum Contract fiscal regime using bargaining game theory to guide contract negotiators

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Petroleum Science 2021年第6期18卷 1887-1898页

作者： mehdi Keshavarz Hossein Iranmanesh Reza Dehghan School of Industrial Engineering College of EngineeringUniversity of TehranP.O.Box:11155/4563TehranIran Faculty of Civil Engineering Science and Research BranchIslamic Azad UniversityTehranIran

Based on Iran's sixth development plan,the country's oil and gas industry requires an investment of about$200 bn in the next five years to increase *** Iranian government,to attract and motivate international oil company investment in their oil and gas fields,has presented a new type of risk service contract:the Iranian Petroleum Contract(IPC).This paper summarizes the features of the IPC and presents mathematical models of its fiscal regime for the benefit and guidance of both the National Iranian Oil Company(NIOC)and the ***,adopting bargaining game theory provides a mathematical model for reaching a win-win situation between the NIOC and the ***,a numerical example is given and a sensitivity analysis performed to illustrate the implementation of the proposed *** contractor and the NIOC may use these models when preparing their proposal and in the course of actual negotiations to calculate their internal rate of return,remuneration fee,and net present value for developing the fields at different conditions of their bargaining power,and derive a logical bargain to protect their best possible interests.

关键词： Iranian petroleum contract Fiscal regime Internal rate of return Bargaining game theory

Simply synthesized TiO_2 nanorods as an effective scattering layer for quantum dot sensitized solar cells

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Chinese Physics B 2014年第4期23卷 531-538页

作者： Mahmoud Samadpour Azam Iraji zad mehdi Molaei Department of Physics Faculty of Science K. N. Toosi University of Technology Institute for Nanoscience and Nanotechnology Sharif University of Technology Department of Physics Sharif University of Technology Department of Physics Faculty of ScienceVali-e-Asr University

TiO2 nanorod layers are synthesized by simple chemical oxidation of Ti substrates. Diffuse reflectance spectroscopy measurements show effective light scattering properties originating from nanorods with length scales on the order of one micron. The films are sensitized with CdSe quantum dots （QDs） by successive ionic layer adsorption and reaction （SILAR） and integrated as a photoanode in quantum dot sensitized solar cells （QDSCs）. Incorporating nanorods in photoanode structures provided 4- to 8-fold enhancement in light scattering, which leads to a high power conversion efficiency, 3.03% （Voc = 497 mV, Jsc = 11.32 mA/cm2, FF = 0.54）, in optimized structures. High efficiency can he obtained just by tuning the photoanode structure without further treatments, which will make this system a promising nanostructure for efficient quantum dot sensitized solar cells.

关键词： solar cell nanorod quantum dot scattering

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

A two-dimensional limit equilibrium computer code for analysis of complex toppling slope failures

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第1期13卷 114-130页

作者： Akbar Ardestani mehdi Amini Kamran Esmaeili School of Mining Engineering College of EngineeringUniversity of TehranTehranIran Department of Civil and Mineral Engineering University of TorontoTorontoOntarioCanada

Evaluation of blocky or layered rock slopes against toppling failures has remained of great concern for engineers in various rock mechanics *** step-by-step analytical solutions have been developed for analyzing these types of slope ***,manual application of these analytical solutions for real case studies can be time-consuming,complicated,and in certain cases even *** study will first examine existing methods for toppling failure analyses that are reviewed,modified and generalized to consider the effects of a wide range of external and dead loads on slope ***,based on the generalized presented formulae,a Windows form computer code is programmed using Visual C#for analysis of common types of toppling *** parameters,including slope geometry,joint sets parameters,rock and soil properties,ground water level,dynamic loads,support anchor loads as well as magnitudes and forms of external forces,are first loaded into the *** input data are then saved and used to graphically draw the slope *** is followed by automatic identification of the toppling failure mode and a deterministic analysis of the slope stability against this failure *** results are presented using a graphical *** developed code allows probabilistic introduction of the input parameters via probability distribution functions(PDFs)and thus a probabilistic analysis of the toppling failure modes using Monte-Carlo simulation *** allows calculation of the probability of slope ***,several published case studies and typical examples are analyzed with the developed *** outcomes are compared with those of the main references to assess the performance and robustness of the developed computer *** comparisons demonstrate good agreement between the results.

关键词： Rock slope Toppling failures Analytical solution Windows form application Deterministic analysis Probabilistic analysis

Microstructural analysis of marl stabilized with municipal solid waste and nano-MgO

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3258-3269页

作者： Ali Ohadian Navid Khayat mehdi Mokhberi Department of Civil Engineering Ahvaz BranchIslamic Azad UniversityAhvazIran Department of Civil Engineering Estahban BranchIslamic Azad UniversityEstahbanIran

Municipal solid waste(MSW)is accumulating over elapsed time across the world,and it is observed in many projects associated with weak soils,such as ***,effective solutions to the environmental problem are *** techniques for stabilizing marl generally use substances such as lime and cement,which could exacerbate *** this,some new stabilizers,***-MgO,are *** are large quantities of marls and MSW in Shiraz City,*** present study aims to evaluate the feasibility of using nano-MgO as a green low-carbon binder to remove MSW from the environment and make construction projects more *** drained shear tests were conducted to evaluate the mechanical behaviors of the nano-MgO treated marl specimens at high normal *** marl specimens containing MSW percentages of 15%,25%,35%,and 45%and nano-MgO percentages of 0.25%,0.5%,0.75%,and 1%,were *** is found that the marl containing 15%and 25%MSW and 0.5%nano-MgO at 28-d curing can perform cation exchange and form new cementitious *** soils with merely MSW show good performance due to the removal of the kaolinite and the formation of ***,the soil with 25%MSW and 0.5%nano-MgO shows the same strength enhancement as the specimen with the optimal nano-MgO(0.75%)through the formation of dolomite,with a 20.59%increase in strain energy(SE).

关键词： Marl Shear strength Microstructure Nano-MgO Municipal solid waste(MSW)

A STRONG CONVERGENCE THEOREM FOR QUASI-EQUILIBRIUM PROBLEMS IN BANACH SPACES

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Acta Mathematica Scientia 2022年第1期42卷 221-232页

作者： mehdi MOHAMMADI G.Zamani ESKANDANI Department of Mathematics Payame Noor UniversityTehranIran Department of Pure Mathematics Faculty of Mathematical SciencesUniversity of TabrizTabrizIran

In this paper,we study an extragradient algorithm for approximating solutions of quasi-equilibrium problems in Banach *** prove strong convergence of the sequence generated by the extragradient method to a solution of... 详细信息

关键词： demiclosed,extragradient algorithm quasi-equilibrium problem quasiΦ-nonexpansive mapping strong convergence