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      • SCIESCOPUSKCI등재

        A Four Leg Shunt Active Power Filter Predictive Fuzzy Logic Controller for Low-Voltage Unbalanced-Load Distribution Networks

        Fahmy, A.M.,Abdelslam, Ahmed K.,Lotfy, Ahmed A.,Hamad, Mostafa,Kotb, Abdelsamee The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

        Recently evolved power electronics' based domestic/residential appliances have begun to behave as single phase non-linear loads. Performing as voltage/current harmonic sources, those loads when connected to a three phase distribution network contaminate the line current with harmonics in addition to creating a neutral wire current increase. In this paper, an enhanced performance three phase four leg shunt active power filter (SAPF) controller is presented as a solution for this problem. The presented control strategy incorporates a hybrid predictive fuzzy-logic based technique. The predictive part is responsible for the SAPF compensating current generation while the DC-link voltage control is performed by a fuzzy logic technique. Simulations at various loading conditions are carried out to validate the effectiveness of the proposed technique. In addition, an experimental test rig is implemented for practical validation of the of the enhanced performance of the proposed technique.

      • KCI등재

        A Four Leg Shunt Active Power Filter Predictive Fuzzy Logic Controller for Low-Voltage Unbalanced-Load Distribution Networks

        A. M. Fahmy,Ahmed K. Abdelslam,Ahmed A. Lotfy,Mostafa Hamad,Abdelsamee Kotb 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

        Recently evolved power electronics’ based domestic/residential appliances have begun to behave as single phase non-linear loads. Performing as voltage/current harmonic sources, those loads when connected to a three phase distribution network contaminate the line current with harmonics in addition to creating a neutral wire current increase. In this paper, an enhanced performance three phase four leg shunt active power filter (SAPF) controller is presented as a solution for this problem. The presented control strategy incorporates a hybrid predictive fuzzy-logic based technique. The predictive part is responsible for the SAPF compensating current generation while the DC-link voltage control is performed by a fuzzy logic technique. Simulations at various loading conditions are carried out to validate the effectiveness of the proposed technique. In addition, an experimental test rig is implemented for practical validation of the of the enhanced performance of the proposed technique.

      • KCI등재

        Reliability and Safety of Cross-Leg Free Latissmus Dorsi Muscle Flap in Reconstruction of Mutilating Leg Injuries Using End-to-Side Anastomosis

        Abdelmegeed Ahmed Gaber,Hifny Mahmoud A.,Abulezz Tarek A.,Saied Samia,Ellabban Mohamed A.,Abo-Saeda Mohamed Abdel-Al,Allam Karam A.,Haredy Mostafa Mamdoh,Mazeed Ahmed S. 대한성형외과학회 2023 Archives of Plastic Surgery Vol.50 No.5

        Background Free tissue transfer is considered the gold standard option for the reconstruction of distal leg defects. Free tissue transfer using recipient vessels in the contralateral leg (cross-leg bridge) is a potential option to supply the flap if there are no suitable recipient vessels in the injured leg. Most studies have described this technique using end-to-end anastomosis which sacrifices the main vessel in the uninjured leg. This study evaluated the use of a cross-leg free latissimus dorsi muscle flap for the reconstruction of defects in single-vessel legs, using end-to-side anastomosis to recipient vessels in the contralateral leg without sacrificing any vessel in the uninjured leg.Methods This is a retrospective study that included 22 consecutive patients with soft tissue defects over the lower leg. All the reconstructed legs had a single artery as documented by CT angiography. All patients underwent cross-leg free latissimus dorsi muscle flap using end-to-side anastomosis to the posterior tibial vessels of the contralateral leg.Results The age at surgery ranged from 12 to 31 years and the mean defect size was 86 cm2. Complete flap survival occurred in 20 cases (91%). One patient had total flap ischemia. Another patient had distal flap ischemia.Conclusion Cross-leg free latissimus dorsi muscle flap is a reliable and safe technique for the reconstruction and salvage of mutilating leg injuries, especially in cases of leg injuries with a single artery. As far as preservation of the donor limb circulation is concerned, end-to-side anastomosis is a reasonable option as it maintains the continuity of the donor leg vessels.

      • SCOPUSKCI등재

        Optimization, Purification, and Characterization of Haloalkaline Serine Protease from a Haloalkaliphilic Archaeon Natrialba hulunbeirensis Strain WNHS14

        ( Rania S Ahmed ),( Amira M Embaby ),( Mostafa Hassan ),( Nadia A Soliman ),( Yasser R Abdel-fattah ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 한국미생물·생명공학회지 Vol.49 No.2

        The present study addresses isolation, optimization, partial purification, and characterization of a haloalkaline serine protease from a newly isolated haloarchaeal strain isolated from Wadi El Natrun in Egypt. We expected that a two-step sequential statistical approach (one variable at a time, followed by response surface methodology) might maximize the production of the haloalkaline serine protease. The enzyme was partially purified using Hiprep 16/60 sephacryl S-100 HR gel filtration column. Molecular identification revealed the newly isolated haloarchaeon to be Natrialba hulunbeirensis strain WNHS14. Among several tested physicochemical determinants, casamino acids, KCl, and NaCl showed the most significant effects on enzyme production as determined from results of the One-Variable-At-A-time (OVAT) study. The Box- Behnken design localized the optimal levels of the three key determinants; casamino acids, KCl, and NaCl to be 0.5% (w/v), 0.02% (w/v), and 15% (w/v), respectively, obtaining 62.9 U/ml as the maximal amount of protease produced after treatment at 40℃, and pH 9 for 9 days with 6-fold enhancement in yield. The enzyme was partially purified after size exclusion chromatography with specific activity, purification fold, and yield of 1282.63 U/mg, 8.9, and 23%, respectively. The enzyme showed its maximal activity at pH, temperature, and NaCl concentration optima of 10, 75℃, and 2 M, respectively. Phenylmethylsulfonyl fluoride (PMSF, 5 mM) completely inhibited enzyme activity.

      • SCIESCOPUSKCI등재

        Simplified methods of the 3D-SVPWM for four-wire three-leg inverter

        Awad, Fathy H.,Mansour, Ahmed A.,Marei, Mostafa I.,El-Sattar, Ahmed A. The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.6

        This paper introduces a novel technique for simplification of a three-dimension space vector pulse width modulation (3D-SVPWM). Conventional SVPWM calculations are based on trigonometric functions or several decomposition matrices. Thus, a very fast embedded controller is needed either for two-dimension space vector pulse width modulation (2D-SVPWM) or 3D-SVPWM. The proposed simplified 3D-SVPWM is dedicated to four-wire three-leg inverters. This technique is based on first-order equations of the curve fitting technique to reduce calculation time. Therefore, this method can be implemented with low memory storage and Central Processing Unit (CPU) capability. In addition, high accuracy can be achieved using higher-order equations. Many approaches are introduced for simplifications. The applications of the proposed simplified 3D-SVPWM method are also provided. Simulation results of the proposed simplified 3D-SVPWM and the conventional 3D-SVPWM are discussed. Finally, the results are verified using a real-time simulator based on Typhoon device (402) as Hardware-In-the-Loop. In addition, the controller of the simplified method is implemented and operated on the C2000 LAUNCHXL-F28379D as a low-cost microcontroller kit.

      • KCI등재

        Synthesis, structural, TD-DFT, and optical characteristics of indole derivatives

        Almutlaq N.,Elshanawany Mahmoud M.,Sayed Mostafa,Younis Osama,Ahmed Mostafa,Wachtveitl Josef,Braun Markus,Tolba Mahmoud S.,Al-Hossainy Ahmed F.,Abozeed Amina A. 한국물리학회 2023 Current Applied Physics Vol.45 No.-

        New compounds of (E)-1-(3-chloro-1H-indol-2-yl)-N-(4-methoxyphenyl)methanimine [Indol-M] and (E)-1-(4- (((3-chloro-1H-indol-2-yl)methylene)amino)phenyl)ethan-1-one [Indol-A] were synthesized and subsequently converted to thin films via physical vapor deposition technique. Numerous characterization techniques were used including FTIR, nuclear magnetic resonance, X-ray diffraction, scanning electron microscope, and optical spectroscopy. Additionally, the optimization using TD-DFTD/Mol3 and Cambridge Serial Total Energy Bundle (TD-FDT/CASTEP) was performed. The XRD and FTIR spectra recorded experimentally were confirmed by TD-DFT calculations, proving their molecular structure. As determined by XRD, the crystallite size of [Indol-M]TF and [Indol-A]TF is 72.26 and 62.05 nm, respectively. SEM image depicts a one-dimensional morphological structure made up of tightly packed nanorods. The direct optical energy bandgaps computed using Tauc’s equation for the [Indol-M]TF and [Indol-A]TF are 4.49 eV and 3.31 eV, respectively. As predicted by CASTEP TD-DFT, the optical properties agree well with the experimental values. [Indol-M]TF and [Indol-A]TF present good candidates for optoelectronics and solar cell applications.

      • KCI등재

        Two novel synthetic peptides inhibit quorum sensing-dependent biofilm formation and some virulence factors in Pseudomonas aeruginosa PAO1

        Mostafa N. Taha,Amal E. Saafan,A. Ahmedy,Eman El Gebaly,Ahmed S. Khairalla 한국미생물학회 2019 The journal of microbiology Vol.57 No.7

        Quorum sensing (QS) regulates virulence factor expression in Pseudomonas aeruginosa. Inhibiting the QS-controlled virulence factors without inhibiting the growth of P. aeruginosa is a promising approach for overcoming the widespread resistance of P. aeruginosa. This study was proposed to investigate the effects of two novel synthetic peptides on the biofilm development and virulence factor production of P. aeruginosa. The tested strain was P. aeruginosa PAO1. The results indicated that both of the synthetic peptides (LIVRHK and LIVRRK) inhibited (P < 0.05) the formation of biofilms and the production of virulence factors, including pyocyanin, protease, and rhamnolipids, without inhibiting the growth of PAO1. Additionally, we detected transcriptional changes related to QS and found a significant reduction in the levels of gene expression of lasI, lasR, rhlI, and rhlR. This study demonstrates that LIVRRK and LIVRHK are novel synthetic peptides that can act as potent inhibitors of QS-regulated virulence factors in P. aeruginosa. Moreover, these synthetic peptides have potential applications in the treatment of biofilmrelated diseases. Both peptides may be able to control chronic infections and biofilm-associated problems of P. aeruginosa.

      • SCOPUSKCI등재

        Certain Subclass of p-Valent Meromorphic Functions Associated with Linear Operator

        MOSTAFA, A.O.,AOUF, M.K.,SHAMANDY, A.,ADWAN, EMAN AHMED Department of Mathematics 2015 Kyungpook mathematical journal Vol.55 No.2

        In this paper, we introduce a class of p-valent meromorphic functions associated with linear operator and derive several interesting results of this class.

      • KCI등재

        Response of Wheat Growth and Productivity to Exogenous Polyamines under Lead Stress

        Mostafa M Rady,Mohamed A Seif El-Yazal,Hanan AA Taie,Safia MA Ahmed 한국작물학회 2016 Journal of crop science and biotechnology Vol.19 No.5

        Polyamines [i.e. spermine (Spm), spermidine (Spd) and putrescine (Put)] antagonistic effects on stress imposed by 2.0 mM lead (Pb 2+ ) on growth, yield and its components and changes in the osmoprotectant and endogenous Pb 2+ concentrations, the contents of some nutrients and tissue health in wheat plants were evaluated. Under the three applied polyamine (PAs) applications, the efficiency of wheat plants to tolerate Pb 2+ stress in terms of growth and yield characteristics was noticed to varying degrees. The enhancements in osmoprotectant concentrations and plant health [in terms of relative water content (RWC) and membrane stability index (MSI)], and reductions in electrolyte leakage (EL) and plant Pb 2+ concentration were correlated with the reasonable growth of Pb 2+ -stressed plants and their grain yield. Results point out that, better growth and yield characteristics, MSI, RWC, leaf photosynthetic pigment and osmoprotectant concentrations, and nutrient contents were obtained with seed soaking in 0.25 mM Spm, 0.50 mM Spd or 1.0 mM Put than those generated with seed soaking in water under 2.0 mM Pb 2+ stress. In contrast, EL and the concentration of endogenous Pb 2+ were significantly reduced. However, the Pb 2+ -free control positively exceeded the all stressed treatments. Among all tested PAs, 1.0 mM Put showed the best results and thus is recommended, as seed soaking, for wheat to grow well under Pb 2+ stress.

      • KCI등재

        Assessment of Behavioral Problems in Children Pre- and Post-Cochlear Implant: An Egyptian Study

        Abdelmonem Ahmed Ali,Salah Hisham,Mostafa Heba Ashour,ElMonem Noha A. Abd,Khalil Doaa Mahmoud,Youssef Rabie Sayed,Fahiem Reham Ahmed 대한신경정신의학회 2022 PSYCHIATRY INVESTIGATION Vol.19 No.9

        Objective The present study aimed to detect the behavioral problems pre- and post-cochlear implantation in comparison to normal hearing group to be able to manage these problems to get more benefit from using cochlear implants.Methods A case-control study included 53 children was done. They were divided into 2 groups, the control group included 28 healthy volunteers with normal hearing and the case group included 25 children with severe to profound hearing loss, fitted for cochlear implantation. The Arabic Child Behavior Checklist (CBCL) was used to detect different behavioral problems in both groups. Case group children were followed up and reassessed again by CBCL 3 months later after cochlear implantation.Results There were highly significant differences regarding total scores of internalizing and externalizing domains of empirically based CBCL between the control group and the case group after cochlear implants (p=0.001). There were non-significant differences in children within case group (pre- and post-cochlear implantation) regarding emotional and behavioral problems on both empirically based and Diagnostic and Statistical Manual of Mental Disorders-based CBCL.Conclusion For better results, it is necessary to include a specialist of psychosomatic medicine in the cochlear rehabilitation teamwork.

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