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Active fault tolerant control design for stochastic Interval Type-2 Ta.a.i-Sugeno fuzzy model

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International Journal of Intelligent Computing and Cybernetics 2018年第3期11卷 404-422页

作者： Imen Maalej Donia ben Halima.a.id chokri Rekik Control and Energy Ma.a.ement Laboratory National Engineering School of SfaxUniversity of SfaxSfaxTunisia

Purpose-The purpose of this paper is to look at the problem of fault tolerant control(FTC)for discrete time nonlinear system described by Interval Type-2 Ta.a.i–Sugeno(IT2 TS)fuzzy model subjected to stochastic noise and actuator ***/methodology/approach–An IT2 fuzzy augmented state observer is first developed to estimate simultaneously the system states and the actuator faults since this estimation is required for the design of the FTC control ***,based on the information of the states and the faults estimate,an IT2 fuzzy state feedback controller is conceived to compensate for the faults effect and to ensure a good tracking performance between the healthy system and the faulty *** conditions for the existence of the IT2 fuzzy controller and the IT2 fuzzy observer are given in terms of linear matrix inequalities which can be solved using a two-step computing ***–The paper opted for simulation results which are applied to the three-tank *** results are presented to illustrate the effectiveness of the proposed FTC ***/value–In this paper,the problem of active FTC design for noisy and faulty nonlinear system represented by IT2 TS fuzzy model is *** developed IT2 fuzzy fault tolerant controller is designed such that it can gua.a.tee the stability of the closed-loop ***,the proposed controller allows to accommodate for faults,presents a satisfactory state tracking performance and outperforms the traditional type-1 fuzzy fault tolerant controller.

关键词： Fuzzy logic Fault tolerant control Intelligent control Interval Type-2 Ta.a.i-Sugeno(IT2 TS)fuzzy model Linear matrix inequalities

a.a.ytic Beta-Wavelet Transform-Based Digital Image Watermarking for Secure Transmission

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Computers, Materials & Continua 2022年第3期70卷 4657-4673页

作者： Hesham Alhumyani Ibrahim Alrube Sameer Alsharif Ashraf Afifi chokri ben a.a. Ha.a.S.El-Sayed Osa.a.S.Fa.a.allah Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.11099Taif21944Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.11099Taif21944Saudi Arabia

The rapid development in the information technology field has introduced digital watermark technologies as a solution to prevent unauthorized copying and redistribution of *** article introduces a self-embedded image verification and integrity *** images are firstly split into dedicated segments of the same block ***,different a.a.ytic Beta-Wavelet(ABW)orthogonal filters are utilized for embedding a self-segment watermark for image segment using a predefined *** orthogonal filter coefficients are estimated to improve image reconstruction under different block *** conduct a compa.a.ive study comparing the watermarked images using three kinds of ABW filters for block sizes 64×64,128×128,and 256×*** embed the watermark using the ABW-based image watermarking method in the 2-level middle frequency sub-bands of the ABW digital image *** imperceptibility and robustness of the ABW-based image watermarking method image is evaluated based on the Peak Signal to Noise Ratio(PSNR)and Correlation coefficient *** the implementation results,we came to know that this ABW-based image watermarking method can withstand many image manipulations compared to other existing methods.

关键词： Watermarking ABW median filtering JPEG compression PSNR

Pla.a. Scintigraphic Images Denoising

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Open Journal of Medical Imaging 2013年第4期3卷 116-124页

作者： Fatma Makhlouf Hatem Besbes Nawres Khalifa chokri ben a.a. Basel Solaiman Department Image and Information Processing Technopole Brest-Iroise Bretagne France Higher Institute of Medical Technology of Tunis University of Tunis El Manar Tunis Tunisia Research Group on Intelligent Machines University of Sfax National Engineering School of Sfax Sfax Tunisia Research Unit of Biophysics Faculty of Medicine of Tunis Tunis Tunisia

Scintigraphic images are generally affected by a Poisson type random noise which diminishes qualitatively and quantitatively the images. Restoration techniques aim to “find” an object from one (or several) degraded observation(s). The objective of the restoration is then to produce an image closer to the physical reality. So that the restoration is successful, it is very useful to know the nature of degra.a.ion. In this work, we present a pla.a. scintigraphic acquisition chain modeling. This model takes into account the Poisson noise and its stationarity aspect. Then, we present a compa.a.ive study of the multi-resolution methods used to reduce the noise in scintigraphic images. Scintigraphy is a tool for exploring functionally several pathologies: the ventricular ejection fraction, the renal clea.a.ce and the thyroid activity. Given the fact that scintigraphic images are strongly affected by noise, the objective in this work is to enhance scintigraphic images for a reliable diagnosis and better orientation and understanding of the pathological phenomenon. This paper focuses on two main parts: the first deals with the degra.a.ion of model while the second takes into consideration the comparison of the multi-resolution methods for assessing the quality of scintigraphic images to reduce noise using wavelet, contourlet, curvelet, ridgelet and bandelet transformations.

关键词： Poisson-Noise Scintigraphy Acquisition Wavelet Contourlet Curvelet Ridgelet Bandelet

Multiple pyogenic liver abscess

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World Journal of Gastroenterology 2006年第18期12卷 2962-2963页

作者： Mabrouk Bahloul Anis Chaari Nadia Bouaziz-Khlaf Hatem Kallel Leila Herguefi Hedi Chelly chokri ben Hamida Mounir Bouaziz Service de Réanimation médicale CHU Habib Bourguiba Route el Ain Km 1 3029 Sfax Tunisie

Multiple pyogenic liver abscesses have been rarely described. We report a fa.a. case of multiple pyogenic liver abscesses affecting a 38-year-old woman requiring surgical drainage. Evolution was marked by occurrence of a septic shock with multi-organ system failure. The patient died 48 h after surgery. Causes, therapeutics and outcome of the disease are discussed.

关键词： Liver abscess Septic shock Outcome