Preferred Language
Articles
/
alkej-219
Intelligent H2/H∞ Robust Control of an Active Magnetic Bearings System
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Aug 01 2021
Journal Name
Bulletin Of Electrical Engineering And Informatics
Robust speaker verification by combining MFCC and entrocy in noisy conditions
...Show More Authors

Automatic speaker recognition may achieve remarkable performance in matched training and test conditions. Conversely, results drop significantly in incompatible noisy conditions. Furthermore, feature extraction significantly affects performance. Mel-frequency cepstral coefficients MFCCs are most commonly used in this field of study. The literature has reported that the conditions for training and testing are highly correlated. Taken together, these facts support strong recommendations for using MFCC features in similar environmental conditions (train/test) for speaker recognition. However, with noise and reverberation present, MFCC performance is not reliable. To address this, we propose a new feature 'entrocy' for accurate and robu

... Show More
View Publication Preview PDF
Scopus (12)
Crossref (10)
Scopus Crossref
Publication Date
Fri Mar 12 2021
Journal Name
Sensors
A Robust Handwritten Numeral Recognition Using Hybrid Orthogonal Polynomials and Moments
...Show More Authors

Numeral recognition is considered an essential preliminary step for optical character recognition, document understanding, and others. Although several handwritten numeral recognition algorithms have been proposed so far, achieving adequate recognition accuracy and execution time remain challenging to date. In particular, recognition accuracy depends on the features extraction mechanism. As such, a fast and robust numeral recognition method is essential, which meets the desired accuracy by extracting the features efficiently while maintaining fast implementation time. Furthermore, to date most of the existing studies are focused on evaluating their methods based on clean environments, thus limiting understanding of their potential a

... Show More
View Publication
Scopus (32)
Crossref (33)
Scopus Clarivate Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Iraqi Journal Of Physics
Structural and Magnetic Properties of MnxZn1-xFe2O4 Prepared via Sol-Gel Method
...Show More Authors

      Manganese-zinc ferrite MnxZn1-xFe2O4 (MnZnF) powder was prepared using the sol-gel method. The morphological, structural, and magnetic properties of MnZnF powder were studied using X-ray diffraction (XRD), atomic force microscopy (AFM), energy dispersive X-ray (EDX), field emission-scanning electron microscopes (FE-SEM), and vibrating sample magnetometers (VSM). The XRD results showed that the MnxZn1-xFe2O4 that was formed had a trigonal crystalline structure. AFM results showed that the average diameter of Manganese-Zinc Ferrite is 55.35 nm, indicating that the sample has a nanostructure dimension. The EDX spectrum revealed the presence of transition metals (Mn, Fe, Zn, and O) in Mang

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Oct 19 2021
Journal Name
International Journal Of Online And Biomedical Engineering (ijoe)
Object Tracking Using Adaptive Diffusion Flow Active Model
...Show More Authors

Object tracking is one of the most important topics in the fields of image processing and computer vision. Object tracking is the process of finding interesting moving objects and following them from frame to frame. In this research, Active models–based object tracking algorithm is introduced. Active models are curves placed in an image domain and can evolve to segment the object of interest. Adaptive Diffusion Flow Active Model (ADFAM) is one the most famous types of Active Models. It overcomes the drawbacks of all previous versions of the Active Models specially the leakage problem, noise sensitivity, and long narrow hols or concavities. The ADFAM is well known for its very good capabilities in the segmentation process. In this

... Show More
View Publication
Scopus Clarivate Crossref
Publication Date
Fri Mar 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Active Vibration Suppression of Smart Cantilever Beam with Sliding Mode Observer Using Two Piezoelectric Patches
...Show More Authors

This paper presents a vibration suppression control design of cantilever beam using two piezoelectric ‎patches. One patch was used as ‎an actuator element, while the other was used as a sensor. The controller design was designed via the balance realization reduction method to elect the reduced order model that is most controllable and observable. ‎the sliding mode observer was designed to estimate six states from the reduced order model but three states are only used in the control law. Estimating a number of states larger than that used is in order to increase the estimation accuracy. Moreover, the state ‎estimation error is proved bounded. An ‎optimal LQR controller is designed then using the ‎estimated states with the slid

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Projective Properties for Symmetrical Magnetic Lens by Using Exponential Model
...Show More Authors

A computational investigation is carried out in the field of charged particle optics with the aid of the numerical analysis methods. The work is concerned with the design of symmetrical double pole piece magnetic lens.  The axial magnetic flux density distribution is determined by using exponential model, from which the paraxial-ray equation is solved to obtain the trajectory of particles that satisfy the suggested exponential model.  From the knowledge of the first and second derivatives of axial potential distribution, the optical properties such as the focal length and aberration coefficients (radial distortion coefficient and spiral distortion coefficient) are determined.  Finally, the pole piece profiles capable of pr

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Evaluate the effectiveness of internal control systems and their role in providing an effective governance framework in Sudanese banks
...Show More Authors

   The study aimed to find out the relationship between the dimensions of internal control systems and the availability of an effective governance framework in the Sudanese banks. The study used descriptive and analytical method for collecting and analyzing the study data using SPSS program. The questionnaire was used as an analysis tool. The target sample of Sudanese bank employees, the study found several results, including that the bank avoids methods that lead to the rational use of available resources, and identifies and separation of tasks among employees, in addition to rapid response to reports The study found several recommendations, including the need for a list of banks that are sufficiently flexible and comp

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 03 2013
Journal Name
Baghdad Science Journal
Effect of Magnetic Water Treatment on Prevention of CaCO3 Scales
...Show More Authors

Permanent magnets of different intensities were used to investigate the effect of a magnetic field in the process of preventing deposits of calcium carbonate. The magnets were fixed on the water line from the tap outside. Then heating a sample of this water in flasks and measuring the amount of sediment in a manner weighted differences. These experiments comprise to the change of the velocity of water flow, which amounted to (0.5, 0.75, 1) m/sec through the magnetic fields that are of magnetic strength (2200, 6000, 9250, 11000) Gauss, and conduct measurements, tests and compare them with those obtained from the use of ordinary water.The results showed the effectiveness of magnetic treatment in reducing the rate of deposition of calcium carb

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Apr 22 2025
Journal Name
Journal Of Engineering
Technological Analysis of Flat Surface Conditions by Magnetic Abrasive Finishing Method (MAF)
...Show More Authors

This study introduced the effect of using magnetic abrasive finishing method (MAF) for finishing flat surfaces. The results of experiment allow considering the MAF method as a perspective for finishing flat surfaces, forming optimum physical mechanical properties of surfaces layer, removing the defective layers and decreasing the height of micro irregularities. Study the characteristics which permit judgment parameters of surface quality after MAF method then comparative with grinding

View Publication
Publication Date
Sun Apr 16 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Theoretical Calculations For Sputtering Yield of Iron Bombarding by (H, D, T, He) Ions
...Show More Authors

Extended calculations for  sputtering yield   through bombed Iron – target   by ( H,D ,T ,He )  ions plasma are accomplished .The calculations include changing the  input    parameters  :    the energy  of ( H,D ,T ,He ) ions plasma, the hit target angle of Iron, change  atomic   mass  of incident ion. The program TRIM is used to accomplish these calculations. The results     show   that   sputtering   yield is   directly   dependent   on   these parameters. It can   change the incident angle of ( H,D ,T ,He ) ions   and energy&n

... Show More
View Publication Preview PDF