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Qualification of Three Analytical Wake Models

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Journal of Mechanics Engineering and Automation 2016年第4期6卷 205-211页

作者： Naima Charhouni Mohammed sallaou abdelaziz Arbaoui Mechanics and Integrated Engineering (M2I) department Moulay Ismail University ENSAM Meknes BP 4024 Morocco

The decrease of wind velocity （wake losses） in downstream area of wind turbine is generally quantified using wake models. The overall estimated power of wind farm varies according to reliability of wake model used, however it＇s unclear which model is most appropriate and able to give a high performance in predicting wind velocity deficit. In this subject, a qualification of three analytical wake models （Jensen, lshihara and Frandsen） based on three principal criteria is presented in this paper：（i） the parsimony which characterizes the inverse of model complexity, （ii） the accuracy of estimation in which wake model is compared with the experimental data and （iii） imprecision that is related to assumptions and uncertainty on the value of variables considered in each model. This qualitative analysis shows the inability of wake models to predict wind velocity deficit due to the big uncertainty of variables considered and it sensitivity to wind farm characteristic.

关键词： Wind farm wind turbine wake models parsimony accuracy imprecision.

Variability of Performance Indices of Photovoltaic solar Panels in Operating Conditions in the Littoral Zone of Cameroon

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Computational Water, Energy, and Environmental Engineering 2021年第3期10卷 108-116页

作者： Regine fouda Bella salomé Ndjakomo Essiane simon Koumi Ngoh Boris Fouotsap Higher Technical Teacher’s Training College of Ebolowa University of Yaoundé I Yaoundé Cameroon Laboratory of Technology and Applied sciences The University of Douala Douala Cameroo Laboratory of Electrical Engineering Mechatronics and Signal Processing University of Yaoundé I Yaoundé Cameroon

Photovoltaic cells are generally manufactured under standard test conditions. The operating conditions, very often induce performance losses different from those initially given by the manufacturer. This article presents an experimental acquisition and analysis system that integrates the synthetic efficiency ratio (SER) as a hybrid analysis tool to evaluate the performance of a monocrystalline photovoltaic solar panel, in this case the LW-MS90 panel in the city of Douala. The meteorological data obtained experimentally was used to evaluate these performances according to the manufacturer’s model in MATLAB/Simulink. By comparison with the experimental performances, the results quantify through a certain number of indices, a minimal power drop according to the acquired irradiance estimated at 3.45%. The interest of this approach is to contribute to the prediction of the operating performance of PV panels in the installation phase in non-standard areas.span>

关键词： Photovoltaic Panel Performance synthetic Efficiency

A Transmission Line Fault Classification Approach by support Vector Machines

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Journal of Energy and Power Engineering 2011年第3期5卷 268-274页

作者： A.M. Ibrahim A.Y. abdelaziz s.F. Mekhamer M. Ramadan Electrical Power and Machines Department Faculty of Engineering Ain Shams University Cairo Egypt

This paper presents an approach for shunt faults detection and classification in transmission line using support Vector Machine （sVM）. The paper compares between using three line post-fault current samples for one-half cycle and one-fourth cycle from the inception of the fault as inputs for sVM. Two sVMs are used, first sVMabc is used for faulty phase detection and second sVMg is used for ground detection. sVMs with polynomial kernel with different degrees are used to obtain the best classification score. The classification test results show that the proposed method is accurate and reliable.

关键词： Transmission line protection fault detection fault classification support vector machine.

Theoretical study of Laser Emission for C-Like (Ar XIII), (Ti XVII) and (Fe XXI)

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Open Journal of Applied sciences 2016年第4期6卷 217-233页

作者： Wessameldin s. abdelaziz Th. M. El sherbeni Nahed H. Wahba National Institute of Laser Enhanced sciences Cairo University Giza Egypt Laser and New Materials Laboratory Physics Department Faculty of Science Cairo University Giza Egypt

Energy levels, transition probability and oscillator strengths have been calculated for the Ar XIII, Ti XVII and Fe XXI. The configurations included in the calculations are 2s2 2p2, 2s2 2p 3l (l = s, p & d) and 4l (l ... 详细信息

Energy levels, transition probability and oscillator strengths have been calculated for the Ar XIII, Ti XVII and Fe XXI. The configurations included in the calculations are 2ssup>2sup> 2psup>2sup>, 2ssup>2sup> 2p 3l (l = s, p & d) and 4l (l = s, p, d, & f) of C-like Ar XIII, Ti XVII & Fe XXI which has 69 fine structures by using the fully relativistic flexible atomic code (FAC) program. These data are used in the determination of the reduced population and gain coefficients over a wide range of electron densities from (10sup>+18sup> to 10sup>+23sup>) and at various plasmas temperatures. The results show that the transitions in Arsup>18+sup>, Tisup>22+sup>, and Fesup>26+sup> ions are the most promising laser emission lines in the XUV and soft X-ray spectral regions.

关键词： XUV soft X-Ray Laser Radiation Population Inversion Gain Coefficient

Hybrid Grey Wolf and Dipper Throated Optimization in Network Intrusion Detection systems

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Computers, Materials & Continua 2023年第2期74卷 2695-2709页

作者： Reem Alkanhel Doaa sami Khafaga El-sayed M.El-kenawy abdelaziz A.Abdelhamid Abdelhameed Ibrahim Rashid Amin Mostafa Abotaleb B.M.El-den Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia 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 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 Computer science University of Engineering and TechnologyTaxilaPakistan Department of system Programming South Ural State UniversityChelyabinsk454080Russia

The Internet of Things(IoT)is a modern approach that enables connection with a wide variety of devices *** to the resource constraints and open nature of IoT nodes,the routing protocol for low power and lossy(RPL)networks may be vulnerable to several routing ***’s why a network intrusion detection system(NIDs)is needed to guard against routing assaults on RPL-based IoT *** imbalance between the false and valid attacks in the training set degrades the performance of machine learning employed to detect network ***,we propose in this paper a novel approach to balance the dataset classes based on metaheuristic optimization applied to locality-sensitive hashing and synthetic minority oversampling technique(LsH-sMOTE).The proposed optimization approach is based on a new hybrid between the grey wolf and dipper throated optimization *** prove the effectiveness of the proposed approach,a set of experiments were conducted to evaluate the performance of NIDs for three cases,namely,detection without dataset balancing,detection with sMOTE balancing,and detection with the proposed optimized LsHsOMTE *** results showed that the proposed approach outperforms the other approaches and could boost the detection *** addition,a statistical analysis is performed to study the significance and stability of the proposed *** conducted experiments include seven different types of attack cases in the RPL-NIDs17 *** on the 2696 CMC,2023,vol.74,no.2 proposed approach,the achieved accuracy is(98.1%),sensitivity is(97.8%),and specificity is(98.8%).

关键词： Metaheuristics grey wolf optimization dipper throated optimization dataset balancing locality sensitive hashing sMOTE

Voting Classifier and Metaheuristic Optimization for Network Intrusion Detection

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Computers, Materials & Continua 2023年第2期74卷 3183-3198页

作者： Doaa sami Khafaga Faten Khalid Karim abdelaziz A.Abdelhamid El-sayed M.El-kenawy Hend K.Alkahtani Nima Khodadadi Mohammed Hadwan Abdelhameed Ibrahim Department of Computer sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer science Faculty of Computer and Information SciencesAin Shams UniversityCairo11566Egypt Department of Computer science College of Computing and Information TechnologyShaqra University11961Saudi Arabia Department of Communications and Electronics Delta Higher Institute of Engineering and TechnologyMansoura35111Egypt The Department of Civil and Environmental Engineering Florida International UniversityMiamiFLUSA Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia Computer Engineering and Control systems Department Faculty of EngineeringMansoura UniversityMansoura35516Egypt

Managing physical objects in the network’s periphery is made possible by the Internet of Things(IoT),revolutionizing human *** attacks and unauthorized access are possible with these IoT devices,which exchange data to enable remote *** attacks are often detected using intrusion detection methodologies,although these systems’effectiveness and accuracy are *** paper proposes a new voting classifier composed of an ensemble of machine learning models trained and optimized using metaheuristic *** employed metaheuristic optimizer is a new version of the whale optimization algorithm(WOA),which is guided by the dipper throated optimizer(DTO)to improve the exploration process of the traditionalWOA *** proposed voting classifier categorizes the network intrusions robustly and *** assess the proposed approach,a dataset created from IoT devices is employed to record the efficiency of the proposed algorithm for binary attack *** dataset records are balanced using the locality-sensitive hashing(LsH)and synthetic Minority Oversampling Technique(sMOTE).The evaluation of the achieved results is performed in terms of statistical analysis and visual plots to prove the proposed approach’s effectiveness,stability,and *** achieved results confirmed the superiority of the proposed algorithm for the task of network intrusion detection.

关键词： Voting classifier whale optimization algorithm dipper throated optimization intrusion detection internet-of-things

Metformin alleviates LTA-induced inflammatory response through PPARγ/MAPK/NF-κB signaling pathway in bovine mammary epithelial cells

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BIOCELL 2022年第11期46卷 2443-2454页

作者： abdelaziz ADAM IDRIss ARBAB CHUNQING YIN XUBIN LU YAN LIANG IsMAIL MOHAMED ABDALLA AMER ADAM IDRIs TIANLE XU YONGJIANG MAO ZHANGPING YANG College of Animal science and Technology Yangzhou UniversityYangzhou225009China Joint International Research Laboratory of Agriculture and Agri-Product safety ofMinistry of Education of China Yangzhou UniversityYangzhou225009China Biomedical Research Institute Darfur CollegeNyala63313Sudan shandong Haiding husbandry Co. Ltd.Jinan250100China

Mastitis is a common inflammatory cow mammary infection;that causes significant economic loss in dairy *** the interesting connection between metformin’s anti-inflammatory function and mastitis model induced by LTA in pbMECs,our objective was to prove that metformin was beneficial in suppressing proinflammatory response induced by LTA through modulation of mitogen-activated protein kinase(MAPK)and nuclear factor kappa B(NF-κB)signaling pathways and activation of peroxisome proliferator-activated receptor-γ(PPARγ)in *** proliferation of cells and mRNA expression were measured using EdU assay and quantitative reverse transcriptase-polymerase chain reaction(qRT-PCR).Immunoblotting and immunofluorescence analysis were conducted to evaluate the expression of target proteins in inflammatory and anti-inflammatory responses to metformin and ***,pbMECs were allowed to treat with the PPAR antagonist GW9662,and inflammatory markers were detected in the *** results showed that LTA concentration at 100μg/mL significantly stimulated the MAPK14,IL-6 and IL-1βmRNA expressions compared to the control cells(Pse-dependent tests for *** suppressed the phosphorylation expressions of MAPK(ERK1/2,p38,and JNK)in LTA-stimulated *** also reduced the protein expression of NF-κB,interleukin-8(IL-8),interleukin-1β(IL-1β)and interleukin-6(IL-6)in pbMECs pretreated with *** administration activated PPARγphosphorylation by up-regulating the expression of PPARγin LTA-stimulated *** with GW9662 resulted in increased IL-6 expression,which was reversed by *** findings collectively indicated that metformin act to attenuate LTA-stimulated inflammatory response in pbMECs by suppressing MAPK and NF-κB activation via a mechanism partially dependent on PPARγ*** results suggested that metformin could function as an anti-inflammatory drug in the treatment of mastitis.

关键词： Metformin LTA Primary bovine mammary epithelial cell Anti-inflammatory effect PPARγ Nuclear factor-κB Mitogen-activated protein kinase

Nutritional status and Dietary Habits of school Children in Beni-suef Governorate, Egypt

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Food and Nutrition sciences 2015年第1期6卷 54-63页

作者： shaimaa B. abdelaziz Meray Rene Labib Youssef Amal s. sedrak John Rene Labib Department of Public Health Faculty of Medicine Cairo University Egypt Department of Pediatric Faculty of Medicine Cairo University Egypt

Objectives: Childhood malnutrition is a major concern in developing countries. Therefore, the present study aimed to determine the nutritional status and dietary habits of school children. Methods: This is a community based cross-sectional survey designed to evaluate nutritional status of students aged (5 - 19 years) in Beni-suef Governorate, Egypt, during september-December 2013. A two-stage sampling technique was done;22 government schools were selected in the first stage. In the second stage, 1100 students were selected from the target population of the study. Weight, height, and age data were used to calculate z-scores of the three different nutritional indicators. Dietary habits were studied using a food frequency questionnaire. Results: Underweight (WAZ +2sD). Boys were more underweight (3%) than girls (2.2%). Conversely, girls tend to be more stunted (65.3%) compared to boys (59.9%) in the age group 10 - 14 years. Identified risk factors associated with malnutrition for those aged more than 10 years were: mother education (P-value = 0.03), father education (P-value = 0.04) and family size (P-value = 0.014). Conclusion and Recommendations: Child’s nutritional status is strongly associated with the literacy of both parents and family size. The prevalence of malnutrition can be reduced by implementation of school intervention programs for the socioeconomic development.

关键词： Anthropometry Children Nutritional status school Age

Purification and characterization of glyceraldehyde-3-phosphate dehydrogenase from saline strain Idiomarina loihiensis

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Advances in Biological Chemistry 2013年第2期3卷 170-176页

作者： Ilham Mardad Tarik Baibai Emna Ammar abdelaziz soukri Laboratoire de Physiologie et Génétique Moléculaire Facultédes Sciences Ain ChockUniversitéHassan II-Ain ChockCasablancaMorocco URétude et Gestion des Environnements Urbains et Cotiers LARSENUniversitéde Sfaxécole Nationale d’Ingénieurs de SfaxTunisia

Idiomarina loihiensis was isolated from the salt works in sfax (Tunisia), until now, the characterization of the GAPDH phosphorylante was never studied. Here, we report the isolation and the biochemical characterization of glyceralehyde-3-phosphate dehydrogenase (GAPDH) fromI. loihiensis saline’s bacteria on the basis of the apparent native and subunit molecular weights, physico-chemical and kinetic characterizations. The purification method consisted of two steps, ammonium sulfate fractionation followed by one chromatographic step, namely dye-affinity on Blue sepharose CL-6B. Polyclonal antibodies against the purified enzyme were used to recognize theI. loihiensis GAPDH by Western blotting. The optimum pH of the purified enzyme was 8.5. studies on the effect of temperatures revealed an enzyme increasing activity of about 45?C. The molecular weight of the purified enzyme was 36 kDa determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Non-denaturing polyacrylamide gels yield a molecular weight of 147 kDa. The Michaelis constants for NAD+ and D-glyceraldehyde-3-phosphate estimated was 19 μM and 3.1 μM, respectively. The maximal velocity of the purified enzyme was estimated to be 2.06 U/mg, approximately 6-fold increase in specific activity and a final yield of approximately 32.5%. The physicochemical properties of this GAPDH, being characterized, could be used in further studies.

关键词： Glyceraldehyde-3-Phosphate Dehydrogenase Idiomarina loihiensis Purification NAD^(+) Kinetics saline strain