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International Journal of Automation and computing 2019年第2期16卷 213-225页

作者： Imen Zaidi mohamed chtourou mohamed Djemel Control & Energy Management Laboratory National School of Sfax EngineersUniversity of Sfax

This work deals with robust inverse neural control strategy for a class of single-input single-output(SISO) discrete-time nonlinear system affected by parametric uncertainties. According to the control scheme, in the first step, a direct neural model(DNM)is used to learn the behavior of the system, then, an inverse neural model(INM) is synthesized using a specialized learning technique and cascaded to the uncertain system as a controller. In previous works, the neural models are trained classically by backpropagation(BP) algorithm. In this work, the sliding mode-backpropagation(SM-BP) algorithm, presenting some important properties such as robustness and speedy learning, is investigated. Moreover, four combinations using classical BP and SM-BP are tested to determine the best configuration for the robust control of uncertain nonlinear systems. Two simulation examples are treated to illustrate the effectiveness of the proposed control strategy.

关键词： Discrete time uncertain nonlinear systems neural modelling sliding mode backpropagation (BP) algorithm robust neural control

Decomposition Based Fuzzy Model Predictive Control Approaches for Interconnected Nonlinear Systems

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International Journal of Automation and computing 2019年第3期16卷 369-388页

作者： Latifa Dalhoumi mohamed chtourou mohamed Djemel Control and Energy Management Laboratory (CEM-Lab) National School of Engineering of Sfax

This paper proposes fuzzy model predictive control(FMPC)strategies for nonlinear interconnected systems based mainly on a system decomposition ***,the Takagi-Sugeno(TS)fuzzy model is formulated in such a way to describe the behavior of the nonlinear *** on that description,a fuzzy model predictive control is *** system under consideration is decomposed into several *** each subsystem,the main idea consists of the decomposition of the control action into two parts:The decentralized part contains the parameters of the subsystem and the centralized part contains the elements of other *** to such decomposition,two strategies are defined aiming to circumvent the problems caused by interconnection bet ween *** feasibility and efficiency of the proposed method are illustrated through numerical examples.

关键词： Model predictive control centralized control decentralized control Takagi-Sugeno(TS)fuzzy models·interconnected nonlinear systems fuzzy model predictive control parallel distributed compensation

Two fuzzy internal model control methods for nonlinear uncertain systems

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International Journal of Intelligent Computing and Cybernetics 2017年第2期10卷 223-240页

作者： Amira Aydi mohamed Djemel mohamed chtourou Department of Electrical Engineering National School of Engineering of SfaxUniversity of SfaxSfaxTunisia

Purpose-The purpose of this paper is to use the internal model control to deal with nonlinear stable systems affected by parametric ***/methodology/approach-The dynamics of a considered system are approximated by a Takagi-Sugeno fuzzy *** parameters of the fuzzy rules premises are determined ***,the parameters of the fuzzy rules conclusions are updated using the descent gradient method under inequality constraints in order to ensure the stability of each local *** fact,without making these constraints the training algorithm can procure one or several unstable local models even if the desired accuracy in the training step is *** considered robust control approach is the internal *** is synthesized based on the Takagi-Sugeno fuzzy *** control strategies are *** first one is based on the parallel distribution compensation *** consists in associating an internal model control for each local ***,for the second strategy,the control law is computed based on the global Takagi-Sugeno fuzzy ***-According to the simulation results,the stability of all local models is obtained and the proposed fuzzy internal model control approaches ensure robustness against parametric ***/value-This paper introduces a method for the identification of fuzzy model parameters ensuring the stability of all local *** the resulting fuzzy model,two fuzzy internal model control designs are presented.

关键词： Robust control Uncertainties Descent gradient method Fuzzy modeling Internal model control Nonlinear systems

New stabilization conditions for continuous fuzzy models using their discretized forms

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International Journal of Intelligent Computing and Cybernetics 2014年第4期7卷 397-414页

作者： Ellouze Ameni mohamed Ksantini Jimmy Lauber Francois Delmotte mohamed chtourou Department of Electrical Engineering University of SfaxSfaxTunisia University of Valenciennes and Hainaut-Cambre´sis ValenciennesFrance University of Artois Technoparc Futura BethuneFrance

Purpose–The purpose of this paper is to deal with the stabilization of the continuous-time TakagiSugeno(TS)fuzzy models by using their discretized ***/methodology/approach–In this case,a discrete model is obtained from the discretization of the continuous TS fuzzy *** gains obtained from a non-parallel distributed compensation controller ensuring the stabilization of the discrete model are used to check if the discrete control law used in the continuous time without any zero-order hold can stabilize the continuous TS ***–This method is compared to another published ***/value–Therefore,the originality of this paper consists in the fusion of the two continuous and discrete cases to obtain new stabilization conditions in the continuous *** examples show the interest of the proposed approach.

关键词： Nonlinear control Fuzzy logic LMI Continuous-time T-S fuzzy models Discrete T-S models Discretization Nonquadratic Lyapunov functions Non-PDC control laws Stabilization

Decay rate performance approach for stabilization continuous fuzzy models using their discretized forms

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International Journal of Intelligent Computing and Cybernetics 2015年第4期8卷 383-400页

作者： Ameni Ellouze François Delmotte Jimmy Lauber mohamed chtourou mohamed Ksantini Department of Electrical Engineering National School of Engineers of SfaxUniversity of SfaxSfaxTunisia University of Lille LilleFrance and University of Artois Technoparc FuturaBethuneFrance University of Valenciennes and Hainaut-Cambrésis ValenciennesFrance

Purpose–The purpose of this paper is to deal with the stabilization of the continuous Takagi Sugeno(TS)fuzzy models using their discretized forms based on the decay rate performance ***/methodology/approach–This approach is structured as follows:first,a discrete model is obtained from the discretization of the continuous TS fuzzy *** discretized model is obtained from the Euler approximation method which is used for several ***,based on the decay rate stabilization conditions,the gains of a non-PDC control law ensuring the stabilization of the discrete model are *** by keeping the values of the gains,the authors determine the values of the performance criterion and the authors check by simulation the stability of the continuous TS fuzzy models through the zero order ***–The proposed idea lead to compare the performance continuous stability results with the *** comparison is,also,taken between the quadratic and non-quadratic ***/value–Therefore,the originality of this paper consists in the improvement of the continuous fuzzy models by using their discretized *** this case,the effect of the discretization step on the performances of the continuous TS fuzzy models is *** usefulness of this approach is shown through two examples.

关键词： Non-linear control Stabilization Continuous Takagi Sugeno(TS)fuzzy models Decay rate performance approach Euler discretization Non-PDC control

Are biopsies during endoscopic ultrasonography necessary for a suspected esophageal leiomyoma?Is laparoscopy always feasible?

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World Journal of Clinical Cases 2023年第9期11卷 2116-2118页

作者： Hazem Beji mohamed Fadhel chtourou Slim Zribi Yassine Kallel Mahdi Bouassida Hassen Touinsi Department of General Surgery Hospital mohamed Taher Maamouri Nabeul University of Tunis El Manar-Faculty of Medicine of TunisNabeul 8000Tunisia

The present letter to the editor is related to the work entitled“Large leiomyoma of lower esophagus diagnosed by endoscopic ultrasonography-fine needle aspiration:A case report.”Although endoscopic ultrasonography seems necessary in a suspected leiomyoma of the esophagus,the performance of biopsies via fine needle aspiration is controversial as it increases the risk of complications such as bleeding,infection,and intraoperative *** is the best treatment strategy for small *** with tumor enucleation or esophageal resection can be considered in large leiomyomas.

关键词： Esophageal Leiomyoma Endoscopic ultrasonography Biopsy Surgical resection

An unusual cause of gastric outlet obstruction in a young girl: Trichobezoar

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Open Journal of Gastroenterology 2012年第4期2卷 206-208页

作者： Mahdi Bouassida Hédi Charrada mohamed Fadhel chtourou Lamine Hamzaoui mohamed Monji Mighri mohamed Msaddak Azzouz Hassen Touinsi Sadok Sassi Department of Gastrology Mohamed Tahar Maamouri Hospital Nabeul Tunisia Department of Reanimation Mohamed Tahar Maamouri Hospital Nabeul Tunisia Department of Surgery Mohamed Tahar Maamouri Hospital Nabeul Tunisia

Trichobezoars are an infrequent form of bezoars formed from ingested hair. They are more common in adolescent females with history of trichotillomania. Exceptionally, it can occur in young children making the diagnosis difficult. We report the case of a 6-year-old girl with a history of abdominal pain, distension, weight loss, and attacks of vomiting. Upper gastrointestinal endoscopy revealed a trichobezoar occupying almost the whole gastric cavity. The gastric bezoar was removed by surgery. Gastric trichobezoar is exceptional in young children and can lead to stunting and gastric outlet obstruction. After definitive surgical or endoscopic treatment, pediatric psychiatric consultation should be opted for any mental disorder and for prevention of further recurrence.

关键词： Trichobezoar Young Children Gastric Outlet Obstruction Trichotillomania

An unusual cause of gastric outlet obstruction in a young girl: Trichobezoar

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