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Algiers, Algeria

Attoui I.,Welding and Research Center | Omeiri A.,Annaba University
Energy Conversion and Management

In this paper, a contribution to modeling and fault diagnosis of rotor and stator faults of a Self-Excited Induction Generator (SEIG) in an Isolated Wind Energy Conversion System (IWECS) is proposed. In order to control the speed of the wind turbine, while basing on the linear model of wind turbine system about a specified operating point, a new Fractional-Order Controller (FOC) with a simple and practical design method is proposed. The FOC ensures the stability of the nonlinear system in both healthy and faulty conditions. Furthermore, in order to detect the stator and rotor faults in the squirrel-cage self-excited induction generator, an on-line fault diagnostic technique based on the spectral analysis of stator currents of the squirrel-cage SEIG by a Fast Fourier Transform (FFT) algorithm is used. Additionally, a generalized model of the squirrel-cage SEIG is developed to simulate both the rotor and stator faults taking iron loss, main flux and cross flux saturation into account. The efficiencies of generalized model, control strategy and diagnostic procedure are illustrated with simulation results. © 2014 Elsevier Ltd. All rights reserved. Source

Tala-Ighil N.,Welding and Research Center | Fillon M.,University of Poitiers
Tribology International

Journal bearing characteristics modellization has been investigated in this paper for both cases of texture presence or absence onto the bearing surface. The thermal effect has been studied. The used numerical approach in this analysis is finite difference method. The textured bearing performance enhancement passes essentially by a minimum film thickness and a friction torque improvement through an appropriate surface texture geometry and right texture distribution on the bearing surface. It is found that the simulations results are in good concordance with those issued from the literature. The obtained results by considering the temperature effect are more realistic. © 2015 Elsevier Ltd. All rights reserved. Source

Chetih N.,Welding and Research Center | Messali Z.,University of Bordj Bou Arreridj
3rd International Conference on Control, Engineering and Information Technology, CEIT 2015

This paper presents comparative study and experimentation of Algebraic Reconstruction Technique (ART) and Filter Back Projection (FBP). The ART and FBP methods are used to reconstruct the object from the X-ray projection. The process of creating back the object image from the Radon Transform of the object is known as Image Reconstruction. Image reconstruction is a famous and interesting field which comes under computed tomography. Computed Tomography is used for identifying the hidden or inner defects of objects. In this paper Algebraic Reconstruction technique and Filter Back Projection methods are implemented and the experimented results are compared using performance parameters for various test cases. Projections for the image reconstruction are calculated analytically by defining two phantoms: Shepp-Logan phantom head model and the standard medical image of abdomen. The original images are grayscale images of size 128 × 128, 256 × 256, respectively. © 2015 IEEE. Source

The aim of this work is to develop analytical models for the thermodynamic equilibrium at the interfaces (gas mixture / Quarz Micro Balance sensor arrays based on conducting polymers). Differential equations, which describe the change in the partial sensitivities of the sensor array elements depending on the gas mixture components concentrations, and the sensor array parameters, have been developed. Moreover, the responses of the sensor array as a function of the concentrations of the gas mixture components have been modeled. © Published under licence by IOP Publishing Ltd. Source

Bouhouche S.,Welding and Research Center
Intelligent Systems Reference Library

Quality management and control is a basic and important activity needed along the production process. From raw material to the final product, quality control and testing need an online measurement, control, evaluation and management. Generally, the management system is based on continuous measurements and improvement which is affected by several factors such as environmental perturbations and physical constraints. Methods and techniques of modeling and identification based on the first principle, black and gray box models are widely used. Because the systems are complex such as the mechanical testing where complex effects and interactions take place, it is strongly recommended to use a data driven empirical model. Such a model is based on the analysis of interactions between variables, data exploration, and modeling. The quality management of engineering process is a complex system defined by multivariate interactions between products and processes, where several factors such as the structure and others parameters must be processed to obtain a reliable model for online prediction of the quality behavior of the considered elements. In this work, new methods and techniques will be considered, essentially based on the intelligent approach such as the monitoring of the quality indexes—based model. These approaches are applied to quality monitoring and management of iron and steel products and processes. To give an optimal and a certified or accredited system, intelligent methods and techniques are strongly recommended. The objective of this chapter is to give the main principles of the management of engineering system—based intelligent methods. © Springer International Publishing Switzerland 2015. Source

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