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Intelligent H2/H∞ Robust Control of an Active Magnetic Bearings System

Abstract

Robust controller design requires a proper definition of uncertainty bounds. These uncertainty bounds are commonly selected randomly and conservatively for certain stability, without regard for controller performance.  This issue becomes critically important for multivariable systems with high nonlinearities, as in Active Magnetic Bearings (AMB) System. Flexibility and advanced learning abilities of intelligent techniques make them appealing for uncertainty estimation. The aim of this paper is to describe the development of robust H2/H controller for AMB based on intelligent estimation of uncertainty bounds using Adaptive Neuro Fuzzy Inference System (ANFIS).  Simulation results reveal that the robust controller design objectives of wide bandwidth and improved performance are satisfied for a wide range of frequency variations. It can be concluded that the intelligent uncertainty weighting functions can precisely compensate for the effects of modelling errors and nonlinearities in the system.

Keywords: Active Magnetic Bearings (AMB) , Adaptive Neuro Fuzzy Inference System (ANFIS),  H2/H  robust controller, modelling errors, uncertainty bounds.

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Publication Date
Thu Jan 01 2015
Journal Name
Der Pharma Chemica
Synthesis, characterization and biological evaluation of new potentially active hydrazones of naproxen hydrazide

To synthesize new hydrazone derivatives of naproxen with enhanced anti-inflammatory activity and devoid the ulcerogenic side effects. Hydrazones were synthesized by conjugation of naproxen hydrazide with seven natural and synthetic aldehyde and ketone by using glacial acetic acid as catalyst. The synthesis has been carried out following simple methodology in excellent isolated yields.The structure of the synthesized derivatives has been characterized by elemental microanalysis (CHN), FTIR Spectroscopy, and other physicochemical properties.The anti- inflammatory activity of the synthesized compounds was evaluated in vivo using the egg-white induced edema model in rats, and the results of the biological assay was found to be comparable to Nap

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Scopus (14)
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Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Robust M Estimate With Cubic Smoothing Splines For Time-Varying Coefficient Model For Balance Longitudinal Data

In this research، a comparison has been made between the robust estimators of (M) for the Cubic Smoothing Splines technique، to avoid the problem of abnormality in data or contamination of error، and the traditional estimation method of Cubic Smoothing Splines technique by using two criteria of differentiation which are (MADE، WASE) for different sample sizes and disparity levels to estimate the chronologically different coefficients functions for the balanced longitudinal data which are characterized by observations obtained through (n) from the independent subjects، each one of them is measured repeatedly by group of  specific time points (m)،since the frequent measurements within the subjects are almost connected an

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Publication Date
Wed Jan 01 2014
Journal Name
Siam Journal On Control And Optimization
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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Design and Simulation of L1-Adaptive Controller for Position Control of DC Servomotor

This paper presents L1-adaptive controller for controlling uncertain parameters and time-varying unknown parameters to control the position of a DC servomotor. For the purpose of comparison, the effectiveness of L1-adaptive controller for position control of studied servomotor has been examined and compared with another adaptive controller; Model Reference Adaptive Controller (MRAC). Robustness of both L1-adaptive controller and model reference adaptive controller to different input reference signals and different structures of uncertainty were studied. Three different types of input signals are taken into account; ramp, step and sinusoidal. The L1-adaptive controller ensured uniformly bounded

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
The Effect of Magnetic Water for Chemical Fertilizer in Tomato Plant

The research aims to find ways to minimize the use of quantities of chemical fertilizers in agriculture in order to get to an environment that is free of contaminants. Magnetized water technology used in the experience of planting seeds of tomatoes Thomson type to obtain a higher efficiency to absorb fertilizer NRK in the protected environment of the period from February to June. Magnetized water system used locally made levels Gaues (4800,2500,1500) concentrations of 50 to 100% for each level and the rate of (4) replicates, and results indicated that the severity of the magnet (4800 Gaues) and a concentration of 50% gave the highest percentage of tomato fruit size and intensity ( 1500 Gaues) and a concentration of 100% did not give any inc

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
A Comparative Study of Various Intelligent Algorithms Based Nonlinear PID Neural Trajectory Tracking Controller for the Differential Wheeled Mobile Robot Model

This paper presents a comparative study of two learning algorithms for the nonlinear PID neural trajectory tracking controller for mobile robot in order to follow a pre-defined path. As simple and fast tuning technique, genetic and particle swarm optimization algorithms are used to tune the nonlinear PID neural controller's parameters to find the best velocities control actions of the right wheel and left wheel for the real mobile robot. Polywog wavelet activation function is used in the structure of the nonlinear PID neural controller. Simulation results (Matlab) and experimental work (LabVIEW) show that the proposed nonlinear PID controller with PSO
learning algorithm is more effective and robust than genetic learning algorithm; thi

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Publication Date
Tue Apr 04 2023
Journal Name
International Journal Of Professional Business Review
An Empirical Study to Measure the Impact of Information Technology Governance Under the Control Objectives for Information and Related Technologies on Financial Performance

Purpose: To determine the effect of information technology governance (ITG) under the control objectives for information and related technologies (COBIT) on financial performance is the objective of this study. Additionally, the article seeks to look into the relationships between the factors under consideration.   Theoretical framework: Information technology and operational processes are evaluated and ensure their compliance with the instructions of the Central Bank of Iraq. Therefore, the research dealt with a conceptual framework by reviewing the literature on the importance of the COBIT framework in assessing financial performance.   Design/methodology/approach: To investigate the effect of information technology; we the valu

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Publication Date
Tue Dec 06 2022
Journal Name
Iraqi National Journal Of Nursing Specialties
Effectiveness of an Instructional program on patients with ulcerative colitis adherence for Medication and Diet to prevent Colorectal Cancer: case and control study

ABSTRACT:

Objectives: The study aims to know the effectiveness of the educational program in the patient’s adherence to medication and diet and to know the relationship between the effectiveness of the education program and their demographic data related to the patient’s age, gender, marital status, education level, occupation, monthly income and residence.

Methodology: A quasi -experimental design study was performed on patient who attended to Gastroenterology and Hepatology Teaching Hospital, from March 2021 to September 2021. The non-probability sampling including 50 patients for case study and 30 patients for control group. The questionnaire consists of 3 parts, part one the socio

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Publication Date
Wed May 01 2019
Journal Name
Iraqi Journal Of Science
Evaluation of Heavy Metal Accumulation in Sawa Lake Sediments, Southern Iraq using Magnetic Study

Heavy metal contamination comprises a great concern in the environment. A magnetic study combined with heavy metal analyses was performed in the Sawa Lake in Al-Muthanna governorate (southern Iraq). Concentrations of selected heavy metals (Cr, Fe, Ni, As and Pb) have been measured and magnetic susceptibility (χ) of sediment samples collected from the lake bottom was calculated.

The results confirmed that a cement plant, which is located less than two kilometers away from the lake has no contamination levels on the lake’s sediments. No enhancement in the magnetic susceptibility was observed. X-ray florescence (XRF) was performed for heavy metal analyses.

Spatial variations of χ with the mean value of 4.58 x

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Publication Date
Wed Dec 26 2018
Journal Name
Iraqi Journal Of Science
Influence of the homogeneous magnetic field of the laser-induced breakdown spectroscopy of copper plasma

Copper plasma is generated with the existence of an external magnetic field and without its presence utilizing Nd:YAG laser (1064 nm ,9 ns) in different  pulse laser energy which ranges from(100 to 400) mJ in a vacuum. Plasma parameter beta ) is least than 1, this indicates that the existence of magnetic field confinement effect is proven. Note that both the electron temperature and electron density increases with the laser pulse energy increasing , Both are higher in the presence of a magnetic field.

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