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Recessive Trait Crossover Genetic Algorithm Flight Control System Design
A. A. El-Mahallawy,A. A. Madkour,A. M. Yousef,H. A. Yousef,M. I. El-Singaby 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10
The requirements, design and simulation of a flight control system for precision tracking task, called pitchrate control augmentation system, is considered. This control system is designed for the F-16 fighter aircraft model using the recessive trait crossover genetic algorithm. The behavior of this controller is compared with that of H¥- mixed sensitivity approach. The flight simulations reveal that the desired performance objectives are achieved and that the controller provides acceptable performance in spite of modeling errors and plant parameter variations.
( Waqas Hussain Shah ),( Wajiha Khan ),( Sobia Nisa ),( Michael H. J. Barfuss ),( Johann Schinnerl ),( Markus Bacher ),( Karin Valant-vetschera ),( Ashraf Ali ),( Hiba-allah Nafidi ),( Yousef A. Bin J 한국미생물생명공학회 2024 Journal of microbiology and biotechnology Vol.34 No.7
Fungi generate different metabolites some of which are intrinsically bioactive and could therefore serve as templates for drug development. In the current study, six endophytic fungi namely Aspergillus flavus, Aspergillus tubigenesis, Aspergillus oryzae, Penicillium oxalicum, Aspergillus niger, and Aspergillus brasiliensis were isolated and identified from the medicinal plant, Silybum marianum. These endophytic fungi were identified through intra transcribed sequence (ITS) gene sequencing. The bioactive potentials of fungal extracts were investigated using several bioassays such as antibacterial activity by well-diffusion, MIC, MBC, anti-biofilm, antioxidant, and haemolysis. The Pseudomonas aeruginosa PAO1 was used to determine the antibiofilm activity. The ethyl acetate extract of Aspergillus flavus showed strong to moderate efficacy against Staphylococcus aureus, Escherichia coli, P. aeruginosa, and Bacillus spizizenii. Aspergillus flavus and Aspergillus brasiliensis exhibited significant antibiofilm activity with IC<sub>50</sub> at 4.02 and 3.63 mg/ml, while A. flavus exhibited maximum antioxidant activity of 50.8%. Based on HPLC, LC-MS, and NMR experiments kojic acid (1) and carbamic acid (methylene-4, 1-phenylene) bis-dimethyl ester (2) were identified from A. flavus. Kojic acid exhibited DPPH free radical scavenging activity with an IC<sub>50</sub> value of 99.3 μg/ml and moderate activity against ovarian teratocarcinoma (CH1), colon carcinoma (SW480), and non-small cell lung cancer (A549) cell lines. These findings suggest that endophytic fungi are able to produce promising bioactive compounds which deserve further investigation.
Yousef, A.,Brooks, R.M.,El-Halwany, M.M.,EL-Newehy, M.H.,Al-Deyab, S.S.,Barakat, N.A.M. Ceramurgica ; Elsevier Science Ltd 2016 CERAMICS INTERNATIONAL Vol.42 No.1
Cu<SUP>0</SUP>/S-doped TiO<SUB>2</SUB> nanoparticles (NPs)-decorated carbon nanofibers (CNFs) were introduced as a novel photocatalyst for the hydrolysis of ammonia borane under visible light. Nanofibers were prepared by electrospinning of a solution composed of titanium isopropoxide, polyvinylpyrroliodine, copper acetate tetrahydrate, and ammonium sulfide. Calcination of the formed nanofiber mats in Ar at 800<SUP>o</SUP>C led to thermal decomposition of CuS to Cu<SUP>0</SUP> and S. Finally, the obtained nanofibers revealed a better photocatalytic activity over that of the other used photocatalysts. The hydrogen evolution was approximately 60mL, 35mL, and 20mL in 40min using nanocatalyst and TiO<SUB>2</SUB>-CNFs, and TiO<SUB>2</SUB> NFs, respectively. The good nanofibrous morphology and electron-transfer, and high surface area are the main features of the introduced nanofibers.
Yousef, Ayman,Barakat, Nasser A.M.,EL-Newehy, Mohamed H.,Ahmed, M.M.,Kim, Hak Yong Elsevier 2015 Colloids and surfaces. A, Physicochemical and engi Vol.470 No.-
<P><B>Abstract</B></P> <P>Cu(0) nanoparticles supported on TiO<SUB>2</SUB> nanofibers (Cu-decorated TiO<SUB>2</SUB> NFs) are introduced as an effective photocatalyst for hydrolytic dehydrogenation of ammonia borane (AB) under solar radiation. The introduced Cu-decorated TiO<SUB>2</SUB> NFs were prepared using electrospinning followed by hydrothermal treatment as a novel route for preparation of metal-decorated metal oxide nanofibers. Interestingly, the utilized physicochemical characterizations showed that the prepared nanocatalyst composed of core TiO<SUB>2</SUB> NFs decorated by Cu(0) NPs. A strong photocatalytic activity for catalytic hydrolysis of AB under solar radiation using the introduced nanocatalysts was observed. The results reveal that high rate of hydrogen release from ammonia borane (2.75 equivalent moles) as compared to undecorated TiO<SUB>2</SUB> NFs (1.6 equivalent moles) and pristine Cu NPs (1.2 equivalent moles). The obtained high hydrogen production, in case of the introduced Cu-decorated TiO<SUB>2</SUB> NFs, is attributed to the dual effect of counter parts. Furthermore, the introduced nanofibers could be utilized for three successive cycles with the same efficiency which reflects high stability. Moreover, the photocatalytic activity of the introduced NFs was further confirmed by photodegradation of methylene blue (MB) under solar radiation; complete removal was observed after 120min.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cu(0) nanoparticles covered surface of titanium dioxide nanofibers. </LI> <LI> High catalytic activity in hydrogen release from ammonia borane. </LI> <LI> Prepared photocatalyst can be reused with the same activity. </LI> </UL> </P>
Prediction of compressive strength of concrete using neural networks
Yousef A. Al-Salloum,Abid A. Shah,Saleh H. Alsayed,Tarek H. Almusallam,M.S. Al-Haddad,H. Abbas 사단법인 한국계산역학회 2012 Computers and Concrete, An International Journal Vol.10 No.2
This research deals with the prediction of compressive strength of normal and high strength concrete using neural networks. The compressive strength was modeled as a function of eight variables: quantities of cement, fine aggregate, coarse aggregate, micro-silica, water and super-plasticizer, maximum size of coarse aggregate, fineness modulus of fine aggregate. Two networks, one using raw variables and another using grouped dimensionless variables were constructed, trained and tested using available experimental data, covering a large range of concrete compressive strengths. The neural network models were compared with regression models. The neural networks based model gave high prediction accuracy and the results demonstrated that the use of neural networks in assessing compressive strength of concrete is both practical and beneficial. The performance of model using the grouped dimensionless variables is better than the prediction using raw variables.
Cu<sub>0</sub>- doped TiO<sub>2</sub> nanofibers as potential photocatalyst and antimicrobial agent
Yousef, A.,El-Halwany, M.M.,Barakat, N.A.M.,Al-Maghrabi, M.N.,Kim, H.Y. Korean Society of Industrial and Engineering Chemi 2015 Journal of industrial and engineering chemistry Vol.26 No.-
Cu<SUB>0</SUB> nanoparticles (NPs)-doped TiO<SUB>2</SUB> nanofibers (NFs) were prepared as an effective photodegradation of three azo dyes as well as an antimicrobial agent under visible light. Fabrication of one dimensional zero-valent Cu nanoparticles-doped TiO<SUB>2</SUB> nanofibers with high aspect ratio have been successfully synthesized by simple and low cost; electrospinning technique followed by hydrothermal process. The photocatalytic activity of introduced nanofibers was evaluated by performing of three azo dyes. Catalytic NFs show a superior photodegaradation activity under visible light as well as good antimicrobial activity. Moreover, photocatalyst nanofibers appeared good stability, which was used for three cycles without regeneration.
Reliability Assessment of HFRC Slabs Against Projectile Impact
Nadeem A. Siddiqui,Yousef A. Al?Salloum,Tarek H. Almusallam,Aref A. Abadel,Husain Abbas 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.6
In the present study, a probabilistic procedure is presented for estimating the reliability of hybrid fiber reinforced concrete (HFRC) slabs against the impact of hemispherical nose projectiles considering uncertainties involved in the material, geometric and impact parameters. The influence of hybrid fibers in improving the safety level of reinforced concrete slabs against impact loads has also been studied on a parametric basis. The failure of the HFRC slabs was assumed to occur when the impact velocity of the projectile exceeds the ballistic limit of the slab i.e. perforates the slab. To illustrate the procedure, a probabilistic analysis was carried out on the impact test results of HFRC slabs containing different proportions of hooked-end steel, polypropylene and Kevlar fibers, recently published by the authors. Reliability assessment was performed for a range of applied nominal impact loads by varying the impact velocity of the given projectile. Reliability analysis yields the safety level of all the HFRC slabs against the impact of the above projectile. Effect of fibers, especially steel fibers, and slab thickness on the reliability of HFRC slabs are also investigated on a parametric basis.
Experimental Investigation on Vulnerability of Precast RC Beam-column Joints to Progressive Collapse
Tarek H. Almusallam,Hussein M. Elsanadedy,Yousef A. Al-Salloum,Nadeem A. Siddiqui,Rizwan A. Iqbal 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.10
The multi-story buildings are susceptible to progressive collapse in the event of the removal of one or more columns due to the exposure to blast loads. The lack of structural continuity in precast concrete buildings makes these buildings more vulnerable to progressive collapse as compared to the regular cast-in-situ concrete buildings. This study presents experiments involving two types of detailing of precast beam-column joints using half-scale test specimens when the middle column is suddenly removed. The test specimens represent the most prevalent precast beam-column joints. One conventional cast-in-situ test specimen, having continuous top and bottom beam rebars, was used for comparison. The progressive collapse scenario was simulated by removing the central column support and applying a sudden vertical load on this column at a rate of 100 mm/s until failure. Test results helped in developing better understanding about the progressive collapse potential in the existing precast buildings. This study highlights the need for the rehabilitation of beam-column connections in existing precast buildings and necessitates the need for innovative beamcolumn connections for improving the progressive collapse resistance.
Effect of molar ratios on strength, microstructure & embodied energy of metakaolin geopolymer
Abadel, Aref A.,Albidah, Abdulrahman S.,Altheeb, Ali H.,Alrshoudi, Fahed A.,Abbas, Husain,Al-Salloum, Yousef A. Techno-Press 2021 Advances in concrete construction Vol.11 No.2
In this study, twenty-five geopolymer (GP) mixes were prepared by varying the alkaline solids to Metakaolin (MK) and sodium silicate to NaOH ratios from 0.1 to 0.5 and 0.2 to 1.0, respectively, thus giving a wide range of molar ratios of silica to alumina, sodium oxide to alumina and water to sodium oxide. The compressive strength of these GP mixes was determined for four curing schemes involving oven curing at 100℃ for 24 h and three ambient curing with the curing ages of 3, 14, and 28 days. The test results revealed that for the manufacture of GP binder for structural applications of strength up to 90 MPa, the molar ratio of silica to alumina should be greater than 2.3, sodium oxide to alumina should be between 0.6 to 1.2, and water to sodium oxide should not exceed 12. The compressive strength of ambient cured GP mortar gets stabilized at 28 days of ambient curing. Experimental findings were also corroborated by GP microstructure analysis. The embodied energy of MK-based GP mortars, especially of high strength, is significantly less than the cement mortar of equivalent strength.
Barakat, N.A.M.,Abdelkareem, M.A.,Yousef, A.,Al-Deyab, S.S.,El-Newehy, M.,Kim, H.Y. Pergamon Press ; Elsevier Science Ltd 2013 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Vol.38 No.8
Cd-doped Cobalt nanoparticles encapsulated in graphite shell have been synthesized using a simple sol-gel technique. Typically, a sol-gel composed of cadmium acetate, cobalt acetate and poly(vinyl alcohol) has been prepared based on the polycondensation property of the acetates. The utilized physiochemical characterizations affirmed that drying, grinding and calcination in Ar atmosphere of the prepared gel leads to produce Cd-doped Co nanoparticles encapsulated in a thin graphite layer. The prepared nanoparticles revealed good electroactivity towards methanol electrooxidation. High current density (70 mAcm<SUP>-2</SUP>) and considerably low onset potential (~600 mV vs. NHE) were obtained. Moreover, because of the graphite shell, good stability was observed. Considering that the introduced nanoparticles composed of nonprecious metals and the obtained electrochemical results are satisfactory, the introduced study might open new avenues for the cobalt-based nanostructures to be used as novel effective electrocatalysts in the fuel cells applications.