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Spatial variation of coda wave attenuation using aftershocks of the Al Hoceima earthquake of 24 February, 2004, Morocco

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Natural Science 2013年第8期5卷 72-77页

作者： Abderrahim Boulanouar Lahcen El Moudnib Mimoun Harnafi taj-eddine cherkaoui Abdelaali Rahmouni Mohamed Boukalouch Jamal Sebbani Earth Science Department Scientific Institute Mohammed V University-Agdal Rabat Morocco Physics Department Faculty of Science Mohammed V University-Agdal Rabat Morocco Physics Department Faculty of Science Mohammed V University-Agdal Rabat Morocco Earth Science Department Scientific Institute Mohammed V University-Agdal Rabat Morocco

On 24th February 2004 a significant earthquake (Md = 6.4) occurred in the north of Moroccocausing great damage in the vicinity of Al Hoceima region. This area is characterized by a complex faulting system as a result of compressional tectonic forces. Three short period seismic stations are set in this area of interest and recordings from these stations were used in this study. In order to complete our knowledge of attenuation, 60 local earthquakes are recorded a few days after the great earthquake with magnitude Ml 2.6 - 5.0 to estimate seismic attenuation. For this purpose, we applied the single backscattering model of Aki & Chouet 1975 inthe frequency range for 1 to 8 Hz. The study of coda waves was limited to a relatively short lapse time (20 Seconds) in order to sample the earth’s crust only. The values of Qc estimated for all the three stations show a strong frequency dependent relationship of the form Qc = Q0fn, where Q0 is Qc at 1 Hz , and n represents the degree of frequency dependence, and reflects the level of crustal heterogeneities to varying degrees. The average frequency dependent attenuation relationship has been obtained which indicates that the attenuation is high in this region. Finally to conclude our work, the values of Q0 suggest that Al Hoceima area is highly heterogeneous and the n parameter indicates a meaning frequency dependence of Qc.

关键词： Attenuation Coda Waves Single Backscattering Model Al Hoceima Morocco Seismic Earthquake

Comparative study of various artificial intelligence approaches applied to direct torque control of induction motor drives

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Frontiers in Energy 2013年第4期7卷 456-467页

作者： Moulay Rachid DOUIRI Mohamed cherkaoui Department of Electrical Engineering Mohammadia Engineering School Avenue lbnSina 765 Agdal Rabat Morocco

In this paper, three intelligent approaches were proposed, applied to direct torque control （DTC） of induction motor drive to replace conventional hysteresis comparators and selection table, namely fuzzy logic, artificial neural network and adaptive neuro-fuzzy inference system （ANFIS）. The simulated results obtained demonstrate the feasibility of the adaptive network-based fuzzy inference system based direct torque control （ANFIS-DTC）. Compared with the classical direct torque control, fuzzy logic based direct torque control （FL-DTC）, and neural networks based direct torque control （NN- DTC）, the proposed ANFIS-based scheme optimizes the electromagnetic torque and stator flux ripples, and incurs much shorter execution times and hence the errors caused by control time delays are minimized. The validity of the proposed methods is confirmed by simulation results.

关键词： adaptive neuro-fuzzy inference system (ANFIS) artificial neural network direct torque control (DTC) fuzzy logic induction motor

Value-based healthcare:a novel approach to the evaluation of patient care

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Hepatobiliary Surgery and Nutrition 2018年第2期7卷 125-126页

作者： Patrick Pessaux Zineb cherkaoui Hepato-Biliary and Pancreatic Surgical Unit GeneralDigestiveand Endocrine SurgeryIRCADInstitute for Mini-Invasive Image-Guided Surgery(IHU Strasbourg)University of StrasbourgStrasbourgFrance

Patti et al.(1)have reported an analysis of the literature searching for an evaluation of robotic liver and pancreatic surgery according to a value-based health care(VBHC)*** model was developed by Porter(2)in order to consider the following two aspects:vthe outcomes that matter most to patients,which are defined as the sum of patients’health objectives;vthe costs required to achieve these results.

关键词： al. surgery patients

Pancreatic enucleation:a valid surgical option with encouraging quality of life

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Hepatobiliary Surgery and Nutrition 2023年第4期12卷 570-572页

作者： Zineb cherkaoui Patrick Pessaux Department of Visceral and Digestive Surgery University Hospital of StrasbourgStrasbourgFrance Inserm Unit UMR_S1110 Institute for Research on Viral and Hepatic DiseasesGroup“Relevance and Care Pathways”StrasbourgFrance SSPC(Simplification of Surgical Patient Care) UR UPJV 7518Universitéde Picardie Jules VerneAmiensFrance IHU-Strasbourg Institute of Image-Guided SurgeryStrasbourgFrance

In their study“Pancreatic Enucleation Patients Share the Same Quality of Life as the General Population at Long-Term Follow-Up”,Giuliani et al.(1)assess short-and long-term outcomes including quality of life after pancreatic enucleation(PE).PE aims to preserve endocrine and exocrine function while ensuring surgical ablation of a presumed benign pancreatic tumor(neuroendocrine tumors,mucinous cystadenoma,serous cystadenoma,branch duct intraductal papillary mucinous neoplasms and solid pseudopapillary tumors).

关键词： Pancreatic enucleation(PE) quality of life value-based health care

Neutron-gamma discrimination method based on blind source separation and machine learning

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Nuclear Science and Techniques 2021年第2期32卷 70-80页

作者： Hanan Arahmane El-Mehdi Hamzaoui Yann Ben Maissa Rajaa cherkaoui El Moursli Universite´Paris-Saclay CEAList91120 PalaiseauFrance Equipe des Sciences de la Matie`re et du Rayonnement(ESMaR) Faculty of SciencesMohammed V University in RabatB.P.1014 RPRabatMorocco National Centre for Nuclear Energy Science and Technology(CNESTEN)B.P.1382 R.P.10001RabatMorocco Laboratory of Telecommunications Networks and Service SystemsNational Institute of Posts and TelecommunicationsAllal El Fassi AvenueRabatMorocco

The discrimination of neutrons from gamma rays in a mixed radiation field is crucial in neutron detection *** approaches have been proposed to enhance the performance and accuracy of neutron-gamma ***,their performances are often associated with certain factors,such as experimental requirements and resulting mixed *** main purpose of this study is to achieve fast and accurate neutron-gamma discrimination without a priori information on the signal to be analyzed,as well as the experimental ***,a novel method is proposed based on two *** first method exploits the power of nonnegative tensor factorization(NTF)as a blind source separation method to extract the original components from the mixture signals recorded at the output of the stilbene scintillator *** second one is based on the principles of support vector machine(SVM)to identify and discriminate these *** addition to these two main methods,we adopted the Mexican-hat function as a continuous wavelet transform to characterize the components extracted using the NTF *** resulting scalograms are processed as colored images,which are segmented into two distinct classes using the Otsu thresholding method to extract the features of interest of the neutrons and gamma-ray components from the background *** subsequently used principal component analysis to select the most significant of these features wich are used in the training and testing datasets for ***-variance analysis is used to optimize the SVM model by finding the optimal level of model complexity with the highest possible generalization *** this framework,the obtained results have verified a suitable bias–variance trade-off *** achieved an operational SVM prediction model for neutron-gamma classification with a high true-positive *** accuracy and performance of the SVM based on the NTF was evaluated and validated by comparing it to the charge comparison

关键词： Blind source separation Nonnegative tensor factorization(NTF) Support vector machines(SVM) Continuous wavelets transform(CWT) Otsu thresholding method

Intrusion Detection System Based on an Intelligent Multilayer Model Using Machine Learning

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Journal of Artificial Intelligence and Technology 2024年第4期4卷 332-341页

作者： Ouafae El Aeraj cherkaoui Leghris Laboratory of Mathematics Computer Science and ApplicationsFaculty of Sciences and TechniquesHassanⅡUniversity of CasablancaMohammedia 28806Morocco

With the rapid advent of information technology and social networking,the multiplication of connected devices further exposes users to the vulnerability of their personal *** growing interconnectedness increases the risk of online attacks,underlining the daily challenge of cybersecurity in the face of increasingly sophisticated *** in automatic software updates and the limited responsiveness of devices underline the need for an innovative approach to detecting intrusions and securing *** detection of intrusions within companies is essential to anticipate threats and respond rapidly to *** recommend the use of several tools and methods to counter malicious *** article introduces our innovative development of an automated model called Snort Support Vector Machine(SSVM)based on a hierarchical strategy organized in distinct *** model,automated by the joint use of Python and Shell,merges the efficiency of these languages to guarantee autonomous and resilient *** examining several intrusion detection and prevention systems,the first layer implements a selected system as the initial *** second layer uses machine learning to fill in the gaps in the initial ***,the third layer applies a global evaluation methodology,taking into account execution time,energy consumption,and physical resources in order to orchestrate the entire evaluation *** approach we propose appears to improve on other conventional intrusion detection systems by making the detection process more *** does this by reducing false positives and false negatives compared with existing models.

关键词： intrusion detection system support vector machines snort machine learning

Learning fuzzy controller and extended Kalman filter for sensorless induction motor robust against resistance variation

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Frontiers of Electrical and Electronic Engineering in China 2012年第3期7卷 347-355页

作者： Moulay Rachid DOUIRI Mohamed cherkaoui Department of Electrical Engineering Mohammadia EngineeringSchool Agdal-Rabat Morocco

This paper presents a new sensorless vector controlled induction motor drive robust against rotor resistance variation. Indeed, the speed and rotor resistance are estimated using extended Kalman filter （EKF）. Then, we introduce a new fuzzy logic speed controller based on learning by minimizing cost function. This strategy is based on a topology control self-organized and an algorithm for modifying the knowledge base of fuzzy corrector. The learning mechanism addresses the con- sequences of corrector rules, which are modified according to the comparison between the current speed of machine and an output signal or a desired trajectory. Thus, fuzzy associative memory is constructed to meet the criteria imposed in problems either control or pursuit. The consequent algorithm updating consists of a regulator mechanism allowing a fast and robust learning without unnecessarily compromising the control signal and steady- state performance. The performance of this new strategy is satisfactory, even in the presence of noise or when there are variations in the parameters of induction motor drive.

关键词： extended Kalman filter induction motor,learning fuzzy control rotor resistance sensorless control

Naked Eye and Selective Detection of Copper(II) in Mixed Aqueous Media Using a Cellulose-based Support

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Chemical Research in Chinese Universities 2019年第4期35卷 598-603页

作者： FETTOUCHE Souad BOUKHRISS Aicha TAHIRI Mohamed cherkaoui Omar BAZI Fathallaah GMOUH Said Laboratoire Recherche sur les Materiaux Textile(REN4TEX) Ecole Supeneure des Induseries de Textile et de L'habillement(ESITH)CasablancaBP 7731Maroc Laboratoire Hydrogeochimie et Bassin versant Faculte des Sciences Ain ChockUniversite Hassan IICasablancaB. P 5366Maroc Laboratore Chimie Analytique et Physico-chimie des Materiaux Faculte des Sciences Ben M'sik Universitie Hassan II CasablancaBP 150Macro Laboratoire d'lngeniene et Materiaux(LIMAT) Faculte des Sciences Ben MsikUniv er site Hassan IICasablanceBP 150Maroc

A new colorimetric sensor based-azo dye for Cu^2+ detection was synthesized and characterized by FTIR and NMR spectroscopies. The results showed that the azo dye had a high selective and sensitive recognition toward Cu^2+. The solution containing the sensor changed color from pink to pale yellow with a hypsochromic shift in the presence of Cu^2+. The sensor selectivity and sensitivity toward Cu^2+ ions were investigated by colorimetry and UV-Vis spectroscopy. For practical applications, a cellulosic textile test strip for high-selectivity detection of Cu^2+ ions in aqueous solution was developed using the synthesized azo dye as chromogenic chemosensor molecule, while using a solid cellulose textile as a substrate. As a result, a spectacular color change of the test strip was observed do pending on the amount of copper ions in contact with the strip, which allows an estimation of Cu^2+ concentration by naked eye.

关键词： Copper(II) ions detection Azo dye Chromogenic chemosensor Cellulose-based probe

Comment on:simultaneous versus delayed resection for initially resectable synchronous colorectal cancer liver metastases

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Hepatobiliary Surgery and Nutrition 2021年第1期10卷 131-133页

作者： Gianluca Cassese Zineb cherkaoui Francis Navarro Patrick Pessaux Division of HBP Surgery and Transplantation Department of SurgerySt.Eloi HospitalMontpellier University Hospital-School of MedicineMontpellierFrance Digestive and Endocrine Surgery Department Nouvel Hôpital CivilStrasbourgFrance Institute of Image Guided Surgery(IHU Strasbourg) StrasbourgFrance INSERM UnitéInserm U1110 Institut de Recherche sur les Maladies Vrales et HépatiquesStrasbourgFrance

We read with great interest the recently published article of Boudjema and collaborators(1).The authors evaluated the safety and efficacy of delayed resection(DR)versus simultaneous resection(SR)for patients with initially resectable synchronous colorectal cancer liver metastases(CRC-SLM).The aforementioned study(METASYNC)was the first randomized controlled trial comparing two resection strategies for *** the literature,large retrospective studies didn’t seem to favor one type of treatment,particularly when comparisons are based on a propensity match score(2).

关键词： resection colorectal metastases