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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

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

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

Assessment and prioritization of soil erosion triggering factors using analytical hierarchy process and Taguchi method

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International Journal of Sediment Research 2023年第3期38卷 396-404页

作者： mehdi Hayatzadeh Vahid Moosavi Ramyar Aliramaee Department of Nature Engineering Faculty of Agriculture and Natural Resources Ardakan University Department of Watershed Management Engineering Faculty of Natural Resources and Marine Sciences Tarbiat Modares University Khamsan Representative and Paired Watershed

The main aims of this study are assessing some factors which affect the soil erosion process and evaluating the results of an analytical hierarchy process(AHP) method using the Taguchi method. Firstly, the weights for those factors and levels affecting soil erosion were determined by the AHP method. The determination of weights was based on the opinions of academic researchers, experts, middle managers,and members of the Soil and Water Research Centers in Iran. Secondly, an L32 Taguchi orthogonal array was selected based on the number of factors and levels for the current problem. Accordingly, 32 rainfall events were simulated and sediment yield amounts were measured. Analyzing the results of the Taguchi method, the weights of factors and levels were determined. The results showed that the weights obtained from the AHP method were not in accordance with the results of field measurements and the Taguchi analysis. The AHP method indicated that the main factors have the following order of importance: geological formation, rainfall intensity, silt content of soil as an indicator for the soil texture,vegetation cover, slope steepness, and slope aspect in the study area. However, the Taguchi method found the following order for the main factors: rainfall intensity, geological formation, silt content of soil as an indicator for the soil texture, slope steepness, vegetation cover, and slope aspect. As the Taguchi method works based on the quantitative measurements, the Taguchi results are more reliable rather than subjective methods such as AHP. It was also concluded that the AHP method should be used cautiously in assessing natural phenomena. Therefore, in the cases that in situ measurements are possible, it is better to use quantitative mathematical and statistical methods than to rely to qualitative knowledge based approaches.

关键词： Soil erosion Taguchi method Analytical hierarchy process (AHP) method Optimization

A cost-effective chemo-thermo-poroelastic wellbore stability model for mud weight design during drilling through shale formations

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第4期12卷 768-779页

作者： Saeed Rafieepour Siavash Zamiran mehdi Ostadhassan University of Tulsa TulsaOKUSA Southern Illinois University Carbondale CarbondaleILUSA University of North Dakota Grand ForksNDUSA

Drilling through chemically-active shale formations is of special importance due to time-dependent drilling fluideshale *** physical models presented so far include sophisticated input parameters,requiring advanced experimental facilities,which are costly and in most cases *** this paper,sufficiently-accurate,yet highly practical,models are presented containing parameters easilyderived from well-known data *** ion diffusivity coefficient,the chemical potential was formulated based on the functionality of water activity to solute concentration for common solute species in *** reflection coefficient and solute diffusion coefficient within shale membrane were predicted and compared with experimental *** thermally-induced fluid flow,a model was utilized to predict thermo-osmosis coefficient based on the energy of hydrogen-bond that attained a reasonably-accurate estimation from petrophysical data,***,specific surface area(SSA),and cation exchange capacity(CEC).The coupled chemo-thermo-poroelastic governing equations were developed and solved using an implicit finite difference ***-Coulomb failure criterion was adopted for mud weight required to avoid compressive shear failure and a tensile cut-off failure index for mud weight required to prevent tensile *** showed a close agreement between the suggested model and experimental data from pressure transmission *** from a numerical example for a vertical wellbore indicated that failure in shale formations was time-dependent and a failure at wellbore wall after 85 min of mudeshale interactions was *** was concluded that instability might not firstly occur at wellbore wall as most of the conventional elastic models predict;perhaps it occurs at other points inside the *** effect of the temperature gradient between wellbore and formation on limits of mud window confirmed that the upper limit was more sensitive to the

关键词： Chemo-thermo-poroelastic wellbore stability Shaleefluid interaction Chemo-osmosis Thermo-osmosis

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

Numerical Modelling Investigation of Wave Interaction on Composite Berm Breakwater

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China Ocean Engineering 2021年第5期35卷 631-645页

作者： Seyed Morteza MARASHIAN mehdi ADJAMI Ahmad Rezaee MAZYAK Water and Environmental Engineering Department Faculty of Civil EngineeringShahrood University of TechnologyShahroodIran Faculty of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The breakwaters have experienced many changes during their construction *** changes have been considered to improve their performance,depending on their environmental conditions and *** modelling was conducted using FLOW-3 D *** this study,the wave overtopping from composite berm breakwater as new conceptual structure and the pressure imposed on the composite berm breakwater are considered and *** results show a decrease of 84.01,70.88 and 61.42 percent of the wave overtopping in the composite berm breakwater,in comparison to the rubble mound breakwater,horizontally caisson breakwater and caisson breakwater,***,the pressure applied to the composite berm breakwater with the pressure applied to the horizontally caisson breakwater was compared and *** berm breakwater compared with horizontally caisson breakwater in P1,the amount of the obtained pressure decreased by 52.09%,in P2 the amount of the obtained pressure decreased by 63.07%,in P3 decreased by 76.09%and in Pu,this pressure reduced by53.92%.For the composite berm breakwater,the impact of three types of berms,homogenous berm(Type 1),a berm consisting of armor-filter(Type 2)and multi-layer berm(Type 3)with the aim of optimizing the hydraulic responses and wave interaction on the caisson of the breakwater was examined and *** total,Type 3 will be recommended with a significant reduction in the overtopping values and maximum pressure.

关键词： composite berm breakwater wave interaction berm breakwater wave overtopping pressure rubble mound breakwater horizontally caisson breakwater caisson breakwater

Advantages of using gold hollow nanoshells in cancer photothermal therapy

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Chinese Physics B 2016年第8期25卷 322-330页

作者： Sattar Abbasi Mojtaba Servatkhah Mohammad mehdi Keshtkar Department of Physics Marvdasht Branch Islamic Azad University Department of Physics Payame Noor University

Lots of studies have been conducted on the optical properties of gold nanoparticles in the first region of near infrared（650 nm–950 nm）, however new findings show that the second region of near-infrared（1000 nm–1350 nm） penetrates to the deeper tissues of the human body. Therefore, using the above-mentioned region in photo-thermal therapy（PTT） of cancer will be more appropriate. In this paper, absorption efficiency is calculated for gold spherical and rod-shaped nanoshells by the finite element method（FEM）. The results show that the surface plasmon frequency of these nanostructures is highly dependent on the dimension and thickness of shell and it can be adjusted to the second region of near-infrared. Thus, due to their optical tunability and their high absorption efficiency the hollow nanoshells are the most appropriate options for eradicating cancer tissues.

关键词： surface plasmon absorption efficiency near-infrared nanotubes