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Modern improvement techniques of direct torque control for induction motor drives - a review

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Protection and Control of Modern Power Systems 2019年第1期4卷 138-149页

作者： Najib el Ouanjli Aziz Derouich abdelaziz el ghzizal Saad Motahhir Ali Chebabhi Youness el Mourabit Mohammed Taoussi Laboratory of Production Engineering Energy and Sustainable DevelopmentHigher School of TechnologySidi Mohamed Ben Abdellah UniversityFezMorocco Faculty of Sciences and Technology University of Bordj Bou ArreridjBordj Bou ArreridjAlgeria Laboratory of Systems Integration and Advanced Technologies Faculty of Sciences Dhar El MahrazSidi Mohamed Ben Abdellah UniversityFezMorocco

Conventional direct torque control (DTC) is one of the excellent control strategies available to control the torque of the induction machine (IM). However, the low switching frequency of the DTC causes high ripples in the flux and torque that leads to an acoustic noise which degrades the control performances, especially at low speeds. Many direct torque control techniques were appeared to remedy these problems by focusing specifically on the torque and flux. In this paper, a state of the art review of various modern techniques for improving the performance of DTC control is presented. The objective is to make a critical analysis of these methods in terms of ripples reduction, tracking speed, switching loss, algorithm complexity and parameter sensitivity. Further, it is envisaged that the information presented in this review paper will be a valuable gathering of information for academic and industrial researchers.

关键词： Induction machine Direct torque Control(DTC) Fuzzy logic(FL) Neural network(NN) Sliding mode(SG) Genetic algorithm(GA)

A novel CMOS charge-pump circuit with current mode control 110mA at 2.7V for telecommunication systems

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Journal of Semiconductors 2010年第4期31卷 57-61页

作者： Salahddine Krit Hassan Qjidaa Imad el Affar Yafrah Khadija Ziani Messghati Yassir el-ghzizal Faculty of Sciences Dhar el Mehraz Laboratory of ElectronicSignal-Systymes and Informatic(LESSI)FesMorocco

This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed charge-pump circuit is designed and simulated by SPICE with TSMC 0.35-μm CMOS technology and operates with a 2.7 to 3.6 V supply voltage. It has an area of 0.4 mm^2; it was designed with a frequency regulation of 1 MHz and internal current mode to reduce power consumption.

关键词： switch capacitor charge pump voltage doubler power consumption

Adaptive neural network observer for proton-exchange membrane fuel cell system

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Clean Energy 2023年第5期7卷 1078-1090页

作者： abdelaziz el Aoumari Hamid Ouadi Jamal el-Bakkouri Fouad Giri ERERA National School of Arts and CraftsMohammed V UniversityRabatMorocco LESE Lab ENSEMHassan II UniversityCasablancaMorocco Normandie University UNICAENENSICAENLAC14000 CaenFrance

This paper develops an adaptive neural network(NN)observer for proton-exchange membrane fuel cells(PEMFCs).Indeed,information on the oxygen excess ratio(OER)value is crucial to ensure optimal management of the durability and reliability of the *** OER indicator is computed from the mass of oxygen and nitrogen inside the PEMFC ***,the measurement process of both these masses is difficult and *** solve this problem,the design of a PEMFC state observer is ***,the behaviour of the fuel cell system is highly non-linear and its modelling is *** to this constraint,a multilayer perceptron neural network(MLPNN)-based observer is proposed in this paper to estimate the oxygen and nitrogen *** notable advantage of the suggested MLPNN observer is that it does not require a database to train the ***,the weights of the NN are updated in real time using the output *** addition,the observer parameters,namely the learning rate and the damping factor,are online adapted using the optimization tools of extremum ***,the proposed observer stability analysis is performed using the Lyapunov *** observer performances are validated by simulation under MATLAB®/Simulink®.The supremacy of the proposed adaptive MLPNN observer is highlighted by comparison with a fixed-parameter MLPNN observer and a classical high-gain observer(HGO).The mean rela-tive error value of the excess oxygen rate is considered the performance index,which is equal to 1.01%for an adaptive MLPNN and 3.95%and 9.95%for a fixed MLPNN and HGO,***,a robustness test of the proposed observer with respect to measurement noise is performed.

关键词： fuel cell system(PEMFC) multilayer perceptron neural network(MLPNN)observer optimization extremum seeking(ES) oxygen excess ratio(OER)

Epigenetic regulation of insulin-like growth factor axis in hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第9期22卷 2668-2677页

作者： Hend Mohamed el Tayebi Ahmed Ihab abdelaziz The Molecular Pathology Research Group Department of Pharmacology and Toxicology Faculty of Pharmacy and Biotechnology German University in Cairo

The insulin-like growth factor(IGF) signaling path-way is an important pathway in the process of hepa-tocarcinogenesis,and the IGF network is clearly dysregulated in many cancers and developmental *** hepatocellular carcinoma(HCC),only a minority of patients are eligible for curative treatments,such as tumor resection or liver ***,there is a high recurrence of HCC after surgical tumor *** research efforts have focused on targeting IGF axis members in an attempt to find therapeutic options for many health *** this review,we shed lights on the regulation of members of the IGF axis,mainly by micro RNAs in *** RNAs in HCC attempt to halt the aberrant expression of the IGF network,and a single micro RNA can have multiple downstream targets in one or more signaling *** micro RNAs is a relatively new approach for identifying an efficient radical cure for HCC.

关键词： Hepatocellular carcinoma Insulin-like growth factors Insulin-like growth factor receptors Epigenetics microRNAs

Clinico-epidemiological features of dengue fever in Saudi Arabia

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Asian Pacific Journal of Tropical Medicine 2010年第3期3卷 220-223页

作者： Abdel-Hady el-Gilany abdelaziz eldeib Sabri Hammad Public Health Family and Community Medicine DepartmentCollege of Medicine in Al-HassaKing Faisal University Ministry of Health

Objective:To highlight some clinical and epidemiological features of dengue ***: All patients who were admitted to hospitals in Holly Mecca City,Saudi Arabia and were confirmed as dengue fever(DF) or dengue hemorrhagic fever(DHF) were included in this study. The data were collected from patient files and through direct interview with patients or their *** were followed through their hospital *** laboratory investigations were done and diagnosis was confirmed by ***:Most of cases admitted in stable condition(94.37%) and only one case(1.41%) ***-1 and 3 types were the prevalent dengue viruses and cases in age group 16-44 were the most frequent(70.40%).The most common symptoms was fever reported from all cases followed by headache(74.60%),myalgia and anorexia(67.60%),back pain(59.20%) and chills(54.90%).DF represented(60.57%) of the cases while DHF represented(39.43%).About half of cases had underground water tanks for human use,5.60%had over house roof water tanks and 43.70%had both types,16.90% of these tanks were *** 70.00%of cases reported presence of small collection of water nearby houses and 46.80%reported the presence of mosquitoes within their ***:Most dengue fever cases might be endogenous in origin due to prevalence of mosquitoes and their breeding places within the houses and in nearby *** of mosquitoes and their breeding places will contribute to prevention of dengue fever.

关键词： Dengue fever(DF) Dengue haemorrhagic fever(DHF) Epidemiology Mosquitoes

A New Approach to University IT Project Portfolio Management Based on Multi-Criteria Methods and the COBIT 5 Governance Framework

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Journal of Systems Science and Information 2023年第5期11卷 636-654页

作者： Majida LAAZIRI Khaoula BENMOUSSA abdelaziz el ALAOUI el AMRANI Ahmed MOUCHTACHI Structural Engineering Intelligent Systems and Electrical Energy LaboratoryNational Graduate School of Arts and CraftsHassan Ⅱ UniversityCasablanca 20670Morocco Higher Normal School Moulay Ismail UniversityMeknes 50050Morocco

Project portfolio management is a major challenge for some *** most organizations,there are a large number of projects active at the same time,some not necessarily delivering value or not aligned with their strategic *** universities face a lot of uncertainties when selecting and prioritizing the projects that make up their *** addition,the achievement of those who are aligned with the strategy of the university becomes a great *** to ensure good project portfolio management,the implementation of selection and prioritization methods and processes becomes *** the project portfolio management to be effective,it is necessary to establish a structured method adapted to the needs and strategy of the *** this context,this paper proposes a method for selecting and prioritizing projects within the framework of the portfolio management dedicated to universities,which can promote harmony between the university’s strategy,the needs and the priority objectives for enable better *** method is based on the processes of the COBIT 5 good practice framework,and on the multi-criteria decision-making methods AHP,TOPSIS and the WSM technique,thus,it proposes seven project selection criteria based on the five axes IT governance strategies and two catalysts derived from COBIT 5 *** evaluation and validation of this method was applied in the portfolio management of the Abdelmalek Essaadi Moroccan University(AUE).The result shows that this proposed method has made it possible to make a better selection and prioritization of the portfolio of projects of Abdelmleek Essaadi University having the most value.

关键词： IS governance information systems project portfolio management university governance project prioritization information technology(IT) good practice framework COBIT 5 APO05 multi-criteria decision-making method AHP TOPSIS WSM

Optimized Weighted Ensemble Using Dipper Throated Optimization Algorithm in Metamaterial Antenna

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Computers, Materials & Continua 2022年第12期73卷 5771-5788页

作者： Doaa Sami Khafaga el-Sayed M.el-kenawy Faten Khalid Karim Sameer Alshetewi Abdelhameed Ibrahim abdelaziz AAbdelhamid Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt General Information Technology Department Ministry of DefenseThe Executive AffairsExcellence Services DirectorateRiyadh11564Saudi Arabia Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia

Metamaterial Antennas are a type of antenna that uses metamaterial to enhance *** bandwidth restriction associated with small antennas can be solved using metamaterial *** learning is gaining popularity as a way to improve solutions in a range of *** learning approaches are currently a big part of current research,and they’re likely to be huge in the *** model utilized determines the accuracy of the prediction in large *** goal of this paper is to develop an optimized ensemble model for forecasting the metamaterial antenna’s bandwidth and *** basic models employed in the developed ensemble are Support Vector Regression(SVR),K-NearestRegression(KNR),Multi-Layer Perceptron(MLP),Decision Trees(DT),and Random Forest(RF).The percentages of contribution of these models in the ensemble model are weighted and optimized using the dipper throated optimization(DTO)*** choose the best features from the dataset,the binary(bDTO)algorithm is *** proposed ensemble model is compared to the base models and results are recorded and analyzed *** addition,two other ensembles are incorporated in the conducted experiments for *** ensembles are average ensemble and K-nearest neighbors(KNN)-based *** comparison is performed in terms of eleven evaluation *** evaluation results confirmed the superiority of the proposed model when compared with the basic models and the other ensemble models.

关键词： Metamaterial antenna dipper throated optimization feature selection parameters prediction

Dipper Throated Optimization for Detecting Black-Hole Attacks inMANETs

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Computers, Materials & Continua 2023年第1期74卷 1905-1921页

作者： Reem Alkanhel el-Sayed M.el-kenawy abdelaziz A.Abdelhamid Abdelhameed Ibrahim Mostafa Abotaleb Doaa Sami Khafaga Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt Department of System Programming South Ural State UniversityChelyabinsk454080Russia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia

In terms of security and privacy,mobile ad-hoc network(MANET)continues to be in demand for additional debate and *** more MANET applications become data-oriented,implementing a secure and reliable data transfer protocol becomes a major concern in the ***,MANET’s lack of infrastructure,unpredictable topology,and restricted resources,as well as the lack of a previously permitted trust relationship among connected nodes,contribute to the attack detection burden.A novel detection approach is presented in this paper to classify passive and active black-hole *** proposed approach is based on the dipper throated optimization(DTO)algorithm,which presents a plausible path out of multiple paths for statistics transmission to boost MANETs’quality of service.A group of selected packet features will then be weighed by the DTO-based multi-layer perceptron(DTO-MLP),and these features are collected from nodes using the Low Energy Adaptive Clustering Hierarchical(LEACH)clustering *** is a powerful classifier and the DTO weight optimization method has a significant impact on improving the classification process by strengthening the weights of key features while suppressing the weights ofminor *** hybridmethod is primarily designed to combat active black-hole *** the LEACH clustering phase,however,can also detect passive black-hole *** effect of mobility variation on detection error and routing overhead is explored and evaluated using the suggested *** diverse mobility situations,the results demonstrate up to 97%detection accuracy and faster execution ***,the suggested approach uses an adjustable threshold value to make a correct conclusion regarding whether a node is malicious or benign.

关键词： Black-hole attack mobile ad-hoc network optimization dipper throated optimization

Novel Optimized Feature Selection Using Metaheuristics Applied to Physical Benchmark Datasets

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Computers, Materials & Continua 2023年第2期74卷 4027-4041页

作者： Doaa Sami Khafaga el-Sayed M.el-kenawy Fadwa Alrowais Sunil Kumar Abdelhameed Ibrahim abdelaziz A.Abdelhamid Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Communications and electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt School of Computer Science University of Petroleum and Energy StudiesDehradun248001India Computer Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt Department of Computer Science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer Science College of Computing and Information TechnologyShaqra University11961Saudi Arabia

In data mining and machine learning,feature selection is a critical part of the process of selecting the optimal subset of features based on the target *** are 2n potential feature subsets for every n features in a dataset,making it difficult to pick the best set of features using standard ***,in this research,a new metaheuristics-based feature selection technique based on an adaptive squirrel search optimization algorithm(ASSOA)has been *** using metaheuristics to pick features,it is common for the selection of features to vary across runs,which can lead to *** of this,we used the adaptive squirrel search to balance exploration and exploitation duties more evenly in the optimization *** the selection of the best subset of features,we recommend using the binary ASSOA search strategy we developed *** to the suggested approach,the number of features picked is reduced while maximizing classification accuracy.A ten-feature dataset from the University of California,Irvine(UCI)repository was used to test the proposed method’s performance *** other state-of-the-art approaches,including binary grey wolf optimization(bGWO),binary hybrid grey wolf and particle swarm optimization(bGWO-PSO),bPSO,binary stochastic fractal search(bSFS),binary whale optimization algorithm(bWOA),binary modified grey wolf optimization(bMGWO),binary multiverse optimization(bMVO),binary bowerbird optimization(bSBO),binary hybrid GWO and genetic algorithm 4028 CMC,2023,vol.74,no.2(bGWO-GA),binary firefly algorithm(bFA),and *** results confirm the superiority and effectiveness of the proposed algorithm for solving the problem of feature selection.

关键词： Metaheuristics adaptive squirrel search algorithm optimization methods binary optimizer