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Antimicrobial activity of latex silver nanoparticles using Calotropis procera

Asian Pacific Journal of Tropical Biomedicine 2014年第11期4卷 876-883页

作者： nadia hussein mohamed Mady Ahmed Ismail Wael Moustfa Abdel-Mageed Ahmed Abdelfattah mohamed Shoreit Department of Botany Faculty of ScienceAssiut University Biology Department.Faculty of Science and Art SamtahJazan University Pharmacognosy Department College of PharmacyKing Saud University Pharmacognosy Department Faculty of PharmacyAssiut University

Objective:To synthesize silver nanoparticles(AgNPs) by green methods using scrum latex of Calotropis procera at 80 ℃ and evaluate them against bacteria,dermatophytes and phytopathogenic fungi comparing with the activity of untreated ***:The synthesis of AgNPs was performed by mixing 3%latex scrum extract with the same volume of silver nitrate(2 mmol/L) solution in round flask and heating in water bath at80 ℃.Characterization of silver particles were determined using UV-vis spectrophotometer,transmission electron microscopy(TEM),X-ray diffraction and Fourier transform infrared *** antimicrobial activity of the green synthesized AgNPs was determined against bacteria,dermatophytes and phytopathogenic fungi and compared to the crude untreated latex by agar-well diffusion ***:Biosynthesis of latex silver nanoparticles was successfully obtained by green *** formation of AgNPs has been confirmed by UV-vis,TEM microscopy.X-ray diffraction and Fourier transform infrared *** analysis showed that synthesized AgNPs are highly stable spherical shaped particles,well dispersed with a diameter ranged from 4 nm up to 25 nm and an average size of 12.33 *** showed strong antibacterial activity against Gram-negative bacteria(Escherichia coli,Pseudomonas aeruginosa and Serratia sp.) and antifungal activity against Trichophyton rubrum,Candida albicans and Aspergillus ***:It can be concluded that serum latex of Calotropis pmcera was found to display strong potential for the synthesis of AgNPs as antimicrobial agents through rapid reduction of silver ions(Ag^+ to Ag^0).The green synthesized AgNPs were found to show higher antimicrobial efficacy than crude latex.

关键词： Green synthesis Calotropis procera Latex Silver nanoparticles Antimicrobial activity

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Efficient Computation Offloading of IoT-Based Workflows Using Discrete Teaching Learning-Based Optimization

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Computers, Materials & Continua 2022年第11期73卷 3685-3703页

作者： mohamed K.hussein mohamed H.Mousa Department of Computer Science Faculty of Computers and InformaticsSuez Canal UniversityIsmailiaEgypt Department of Information Technology College of Computer Science at AlKamilUniversity of JeddahJeddahSaudi Arabia

As the Internet of Things(IoT)and mobile devices have rapidly proliferated,their computationally intensive applications have developed into complex,concurrent IoT-based workflows involving multiple interdependent *** exploiting its low latency and high bandwidth,mobile edge computing(MEC)has emerged to achieve the high-performance computation offloading of these applications to satisfy the quality-of-service requirements of workflows and *** this study,we propose an offloading strategy for IoT-based workflows in a high-performance MEC *** proposed task-based offloading strategy consists of an optimization problem that includes task dependency,communication costs,workflow constraints,device energy consumption,and the heterogeneous characteristics of the edge *** addition,the optimal placement of workflow tasks is optimized using a discrete teaching learning-based optimization(DTLBO)*** experimental evaluations demonstrate that the proposed offloading strategy is effective at minimizing the energy consumption of mobile devices and reducing the execution times of workflows compared to offloading strategies using different metaheuristics,including particle swarm optimization and ant colony optimization.

关键词： High-performance computing internet of things(IoT) mobile edge computing(MEC) workflows computation offloading teaching learning-based optimization

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Efficient Channel Estimation Techniques for MIMO Systems with 1-Bit ADC

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China Communications 2020年第5期17卷 50-64页

作者： Hany Shussein Shaimaa hussein Ehab Mahmoud mohamed Electrical Engineering Dept. College of EngineeringKing Khalid UniversityAbha 61411King of Saudi Arabia Electrical Engineering Dept. Faculty of EngineeringAswan UniversityAswan 81542Egypt Electrical Engineering Dept. College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir 11991King of Saudi Arabia

With a low resolution 1-bit ADC on its receiver(RX) side, MIMO with 1-bit ADC took a considerable step in the fulfillment of the hardware complexity constrains of the internet of things(IoT) PHY layer design. However, applying 1-bit ADC at MIMO RX results in severe nonlinear quantization error. By which, almost all received signal amplitude information is completely distorted. Thus, MIMO channel estimation is considered as a major barrier towards practical realization of 1-bit ADC MIMO system. In this paper, two efficient sparsity-based channel estimation techniques are proposed for 1-bit ADC MIMO systems, namely the low complexity sparsity-based channel estimation(LCSCE), and the iterative adaptive sparsity channel estimation(IASCE). In these techniques, the sparsity of the 1-bit ADC MIMO channel is exploited to propose a new adaptive and iterative compressive sensing(CS) recovery algorithm to handle the 1-bit ADC quantization effect. The proposed algorithms are tested with the state-of-the-art 1-bit ADC MIMO constant envelope modulation(MIMO-CEM). The 1-bit ADC MIMO-CEM system is chosen as it fulfills both energy and hardware complexity constraints of the IoT PHY layer. Simulation results reveal the high effectiveness of the proposed algorithms in terms of spectral efficiency(SE) and computational complexity. The proposed LCSCE reduces the computational complexity of the 1-bit ADC MIMO-CEM channel estimation by 86%, while the IASCE reduces it by 96% compared to the recent techniques of MIMO-CEM channel estimation. Moreover, the proposed LCSCE and IASCE improve the spectrum efficiency by 76 % and 73 %, respectively, compared to the recent techniques.

关键词： channel estimation 1-bit ADC MIMO sparsity recovery compressive sensing Internet of things

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Influence of Fe_(2)O_(3) on the physical,structural and electrical properties of sodium lead borate glasses

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Journal of Advanced Ceramics 2014年第2期3卷 155-164页

作者： Safeya IBRAHIM mohamed Mahmoud GOMAA hussein DARWISH Glass Research Department National Research CentreDokkiCairoEgypt Geophysical Sciences Department National Research CentreDokkiCairoEgypt

The influence of adding Fe_(2)O_(3) at the expense of Na_(2)O in sodium lead borate glasses on the structural,physical and electrical properties have been *** obtained from Fourier transform infrared(FTIR)spectra indicated that Fe_(2)O_(3) plays an important role in converting three coordinated boron atoms[BO_(3)]to four coordinated boron atoms[BO4].The physical properties such as density and molar volume helped to evaluate the compact structure of the prepared glass samples due to presence of[BO4]*** increase of Fe_(2)O_(3)/Na_(2)O replacements led to increasing the microhardness values and decreasing the thermal expansion coefficients of the studied *** increase of Fe_(2)O_(3)/Na_(2)O replacements generally decreased the AC *** decrease might be due to converting of the three coordinated boron atoms[BO_(3)]to four coordinated boron atoms[BO_(4)].Dielectric constants of the samples might be an indication of the distortion in the coordinated boron *** obtained experimental data indicated the internal structure of glass network and the change of the structure of the samples from three[BO_(3)]to four coordinated boron atoms[BO4].

关键词： borate glasses Fourier transform infrared(FTIR)spectra microhardness thermal expansion AC electrical properties

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LMI solutions for H-two and H-infinity decentralized controllers applied to an aerothermic process

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控制理论与应用（英文版） 2013年第2期11卷 247-254页

作者： Najib BENNIS Mustapha RAMZI mohamed HALOUA hussein YOULAL ENSET de Rabat Avenue de l'Arme'e Royale Madinat Al Irfane 10100 B. P. 6207 Rabat-InstitutsMorocco LASTIMI EST de sale' Universite' Mohamed V Agdal Avenue Prince sidi Mohammed B.P 227 Sale' Me'dinaMorocco EMI Avenue IbnSina B. P. 765 Agdal RabatMorocco UFR Automatique et Technologies de l'Information Faculte' des Sciences de Rabat Avenue Ibn Batouta B. P. 1014 RabatMorocco

In this paper, we present a linear matrix inequality （LMI）-based solution to implement H-two and H- infinity decentralized robust control strategies. Appropriate parametrization of optimal H-two and H-infinity controllers is used. The general formulation of the decentralized control design leads to the optimal determination of both the state feedback gains and the observer gains of the decentralized controllers. This formulation is two folds： first, a centralized controller is obtained, and then, a simplified decentralized solution is derived by optimizing only the observer gains. The mathematical determination of these gains is formulated as an LMI optimization problem that can be easily solved using LMI solvers. As an experimental evaluation of these controllers, a real time application to an aerothermic process is carried out. A continuous-time model of the process obtained with a suitable direct continuous-time identification approach is elaborated. Results illustrating the real performance obtained from the H-two and H-infinity decentralized controllers are di^cu^ge.d and comnare, d with th~ ce^ntraliTed nn^g

关键词： Parametrization approach Decentralized control H-two/H-infinity control Parameters optimization Lin-ear matrix inequality (LMI) Subspace identification Aerothermic process

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A reinforcement learning approach for thermostat setpoint preference learning

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Building Simulation 2024年第1期17卷 131-146页

作者： hussein Elehwany mohamed Ouf Burak Gunay Nunzio Cotrufo Jean-Simon Venne Department of Environmental Engineering Carleton UniversityOttawaCanada Departmentof Building Civiland Environmental EngineeringConcordia UniversityMontrealCanada BrainBox Al Inc. MontrealCanada

Occupant-centric controls(OcC)is an indoor climate control approach whereby occupant feedback is used in the sequence of operation of building energy *** OcC has been used in a wide range of building applications,an OcC category that has received considerable research interest is learning occupants'thermal preferences through their thermostat interactions and adapting temperature setpoints *** recent studies used reinforcement learning(RL)as an agent for OcC to optimize energy use and occupant *** studies depended on predicted mean vote(PMV)models or constant comfort ranges to represent comfort,while only few of them used thermostat *** paper addresses this gap by introducing a new off-policy reinforcement learning(RL)algorithm that imitates the occupant behaviour by utilizing unsolicited occupant thermostat *** algorithm is tested with a number of synthetically generated occupant behaviour models implemented via the Python APl of *** simulation results indicate that the RL algorithm could rapidly learn preferences for all tested occupant behaviour scenarios with minimal exploration *** substantial energy savings were observed with most occupant scenarios,the impact on the energy savings varied depending on occupants'preferences and thermostat use behaviour stochasticity.

关键词： reinforcement learning preference learning occupant-centric controls smart thermostats off-policy learning

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Effect of smart sprinkler irrigation utilization on water use efficiency for wheat crops in arid regions

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 26-35页

作者： hussein Mohammed Al-Ghobari mohamed Said Abdalla El Marazky Department of Agricultural Engineering College of Food and Agriculture Sciences King Saud UniversityRiyadh 11451Kingdom of Saudi Arabia

The smart irrigation system(SIS)developed in this research is a valuable tool for scheduling irrigation and quantifying water required by *** was implemented and tested under sprinkler irrigation system to irrigate wheat crops(YecoraRojo).Results obtained from this system were compared with the control irrigation system(CIS),whose scheduling method was based on data from an automatic weather *** indicated significant savings in applied water using the *** addition,the use of the SIS conserved 12%of irrigation water compared to CIS and obtained an economical *** water use efficiency(WUE)under SIS had generally higher values(1.64 kg/m^(3))compared to CIS(1.46 kg/m^(3)).Hence,the application of SIS technology provides significant advantages on WUE and irrigation water use efficiency(IWUE).Relatively high WUE and IWUE were found for the irrigation treatment(80%of evapotranspiration under SIS).Results showed that the irrigation requirements of wheat increased(100%of ETc under CIS)with increasing evapotranspiration(ETc)but excessive irrigation could decrease WUE and *** results indicated that extreme irrigation might not produce higher yield or optimal economic benefit,thus,suitable irrigation schedules by using SIS must be established and extendable to other agricultural crops.

关键词： smart irrigation system(SIS) sprinkler irrigation scheduling water use efficiency arid region evapotranspiration grain yield

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Case Study: Spark GPU-Enabled Framework to Control COVID-19 Spread Using Cell-Phone Spatio-Temporal Data

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Computers, Materials & Continua 2020年第11期65卷 1303-1320页

作者： hussein Shahata Abdallah mohamed H.Khafagy Fatma A.Omara Department of Computer Science Fayoum UniversityFayoum63514Egypt Department of Computer Science Cairo UniversityGiza1261Egypt

Nowadays,the world is fighting a dangerous form of Coronavirus that represents an emerging *** its early appearance in China Wuhan city,many countries undertook several strict regulations including lockdowns and social distancing ***,these procedures have badly impacted the world *** and isolating positive/probable virus infected cases using a tree tracking mechanism constitutes a backbone for containing and resisting such fast spreading *** helping this hard effort,this research presents an innovative case study based on big data processing techniques to build a complete tracking system able to identify the central areas of infected/suspected people,and the new suspected cases using health records integration with mobile stations spatio-temporal data *** main idea is to identify the positive cases historical movements by tracking their phone location for the last 14 days(i.e.,the virus incubation period).Then,by acquiring the citizen’s mobile phone locations for the same period,the system will be able to measure the Euclidean distances between positive case locations and other nearby people to identify the in-contact suspected-cases using parallel clustering and classification ***,the daily change of the clusters size and its centroids will be used to predict new regions of infection,as well as,new ***,this approach will support infection avoidance by alerting people approaching areas of high probability of infection using their mobile GPS *** case study has been developed as a simulation system consisting of three components;positive cases/citizens movement’s data generation subsystem,big data processing platform including CPU/GPU tasks,and data visualization/map geotagging *** processing of such a big data system requires intensive computing ***,GPU tasks carried out to achieve high performance and accelerate the data *** to the sim

关键词： Big data Coronavirus(COVID-19) parallel K-Means GPU Spark

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CO_x-Free Hydrogen and Carbon Nanofibers Produced from Direct Decomposition of Methane on Nickel-Based Catalysts

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Journal of Natural Gas Chemistry 2006年第4期15卷 253-258页

作者： Siang-Piao Chai Sharif hussein Sharif Zein Abdul Rahman mohamed School of Chemical Engineering Universiti Sains MalaysiaEngineering Campus Seri Ampangan14300 Nibong TebalSPS Penang Malaysia

Direct decomposition of methane was carried out using a fixed-bed reactor at 700 ℃ for the production of COx-free hydrogen and carbon nanofibers. The catalytic performance of NiO-M/SiO2 catalysts （where M=AgO, CoO, CuO, FeO, MnOx and MoO） in methane decomposition was investigated. The experimental results indicate that among the tested catalysts, NiO/SiO2 promoted with CuO give the highest hydrogen yield. In addition, the examination of the most suitable catalyst support, including Al2O3, CeO2, La2O3, SiO2, and TiO2, shows that the decomposition of methane over NiO-CuO favors SiOx support. Furthermore, the optimum ratio of NiO to CuO on SiO2 support for methane decomposition was determined. The experimental results show that the optimum weight ratio of NiO to CuO fell at 8：2 （w/w） since the highest yield of hydrogen was obtained over this catalyst.

关键词： methane decomposition hydrogen carbon nanofibers supported catalyst

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Prospects delineation and evaluation using the CDP gathers characterization, onshore Nile Delta, Egypt

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Petroleum Research 2019年第4期4卷 365-375页

作者： mohamed hussein Ahmed S.Abu El-Ata mohamed G.El-Behiry Petroleum Engineering Department Faculty of EngineeringFuture University in EgyptEgypt Geophysics Department Faculty of ScienceAin Shams UniversityEgypt Geophysics Department Faculty of ScienceCairo UniversityEgypt

In the last decade, the seismic AVO analysis have become prominent in the direct hydrocarbons indicator(DHI), aimed at characterizing the fluid content or the lithology of a possible reservoir and reducing theexploration drilling risk. This research discuss the impact of studying the common depth point (CDP)gathers on Near, Mid and Far-offsets, to verify the credibility of the amplitude response in the prospectevaluation, through analyzing a case study of two exploratory wells;one has already penetrated a gasbearing sandstone as a reservoir and the other one is dry-sand, but drilled in two different prospects,using the amplitude versus offset (AVO) analysis, to understand the reservoir configuration and itsrelation to the different amplitude response. The results show, that the missing of the short-offset data isthe reason of the false anomaly encountered in the dry sand, due to some urban surface obstacles duringacquiring the seismic data in the field especially, the study area is located in El Mansoura city, which it isa highly cultivated flat terrain, with multiple channels and many large orchards on the edge of the river,and sugar cane and rice fields. Several lessons have been learned, which how to differentiate between thegas reservoirs and non-reservoirs, by understanding the relation between the Near and Far-offset traces,to reduce the amplitude anomalies to their right justification, where missing of Near-offset data led to apseudo-amplitude anomaly. The results led to a high success of exploration ratio as the positives vastlyoutweigh the negatives.

关键词： CDP gathers AVO analysis Seismic attributes Qawasim sands Near-offset

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