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Investigation of SARS-CoV-2 main Protease Potential Inhibitory Activities of Some Natural Antiviral Compounds Via molecular Docking and Dynamics Approaches

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Phyton-International Journal of Experimental Botany 2022年第5期91卷 1089-1104页

作者： Nada m.mostafa muhammad I.Ismail Amr m.El-Araby Dina m.Bahgat ahmed m.Elissawy ahmed m.mostafa Omayma A.Eldahshan Abdel Nasser B.Singab Department of Pharmacognosy Faculty of PharmacyAin Shams UniversityCairo11566Egypt Department of Pharmaceutical Chemistry Faculty of PharmacyThe British University in EgyptCairo11837Egypt Department of Pharmaceutical Chemistry Faculty of PharmacyAin Shams UniversityCairo11566Egypt Department of Biochemistry Faculty of PharmacyAin Shams UniversityCairo11566Egypt Center for Drug Discovery and Development Research Ain Shams UniversityCairo11566Egypt

Coronaviruses caused an outbreak pandemic disease characterized by a severe acute respiratory distress syndrome leading to the infection of more than 200 million patients and the death of more than 4 million *** primary treatment is either supportive or *** products have an important role in the development of various ***,screening of natural compounds with reported antiviral activities can lead to the discovery of potential inhibitory entities against *** the current study,an in-silico molecular docking experiment was conducted on the effects of some of these natural antiviral phytoconstituents,(e.g.,procyanidin B2,theaflavin,quercetin,ellagic acid,caffeoylquinic acid derivatives,berginin,eudesm-1β,6α,11-triol and arbutin),on the crystal structure of SARS-CoV-2 main protease(PDB ID:6w63)using AutoDock-Vina *** of the docked compounds revealed good binding affinity,with procyanidin B2(–8.6 Kcal/mol)and theaflavin(–8.5 Kcal/mol)showing a better or similar binding score as the ligand(–8.5 Kcal/mol).molecular dynamics simulations were carried out at 100 ns and revealed that procyanidin B2 forms a more stable complex with SARS-CoV-2 main protease than *** B2,theaflavin,and 4,5-dicaffeoylquinic acid were evaluated for toxicity by ProTox-II webserver and were non-toxic according to the predicted LD50 values and safe on different organs and ***,these phytoconstituents showed good ADmE properties and acceptable lipophilicity,as evaluated using *** the tested compounds,procyanidin B2 showed the highest lipophilic *** is worth mentioning that these natural inhibitiors of SARS-CoV-2 main protease are components of green and black tea that can be used as a supporting supplement for COVID patients or as potential nuclei for further drug design and development campaigns.

关键词： Coronavirus natural products SARS-CoV-2 main protease molecular docking molecular dynamics tea

ATS:A Novel Time-Sharing CPU Scheduling Algorithm Based on Features Similarities

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Computers, materials & Continua 2022年第3期70卷 6271-6288页

作者： Samih m.mostafa Sahar ahmed Idris manjit Kaur Faculty of Computers and Information South Valley UniversityQena83523Egypt College of Industrial Engineering King Khalid UniversityAbhaSaudi Arabia School of Engineering and Applied Sciences Bennett UniversityGreater NoidaIndia

minimizing time cost in time-shared operating systems is considered basic and essential task,and it is the most significant goal for the researchers who interested in CPU scheduling *** time,turnaround time,and number of context switches are themost time cost criteria used to compare between CPU scheduling *** scheduling algorithms are divided into non-preemptive and ***(RR)algorithm is the most famous as it is the basis for all the algorithms used in *** this paper,the authors proposed a novel CPU scheduling algorithm based on *** proposed algorithm is called Adjustable Time Slice(ATS).It reduces the time cost by taking the advantage of the low overhead of RR *** addition,ATS favors short processes allowing them to run longer time than given to long *** specific characteristics of each process are;its CPU execution time,weight,time slice,and number of context *** clusters the processes in groups depending on these *** traditionalRRassigns fixed time slice for each *** the other hand,dynamic variants of RR assign time slice for each process differs from other *** essential difference between ATS and the other methods is that it gives a set of processes a specific time based on their similarities within the same *** authors compared between ATS with five popular scheduling algorithms on nine datasets of *** datasets used in the comparison vary in their *** evaluation was measured in term of time cost and the experiments showed that the proposed algorithm reduces the time cost.

关键词： Clustering CPU scheduling round robin average turnaround time average waiting time

An Adjustable Variant of Round Robin Algorithm Based on Clustering Technique

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Computers, materials & Continua 2021年第3期66卷 3253-3270页

作者： Samih m.mostafa Hirofumi Amano Faculty of Computers and Information South Valley UniversityQena83523Egypt Research Institute for Information Technology Kyushu UniversityFukuoka819-0395Japan

CPU scheduling is the basic task within any time-shared operating *** of the main goals of the researchers interested in CPU scheduling is minimizing time *** between CPU scheduling algorithms is subject to some scheduling criteria(e.g.,turnaround time,waiting time and number of context switches(NCS)).Scheduling policy is divided into preemptive and *** Robin(RR)algorithm is the most common preemptive scheduling algorithm used in the time-shared operating *** this paper,the authors proposed a modified version of the RR algorithm,called dynamic time slice(DTS),to combine the advantageous of the low scheduling overhead of the RR and favor short process for the sake of minimizing time *** process has a weight proportional to the weights of all *** process’s weight determines its time slice within the current *** authors benefit from the clustering technique in grouping the processes that are similar in their attributes(e.g.,CPU service time,weight,allowed time slice(ATS),proportional burst time(PBT)and NCS).Each process in a cluster is assigned the average of the processes’time slices in this cluster.A comparative study of six popular scheduling algorithms and the proposed approach on nine groups of processes vary in their attributes was performed and the evaluation was measured in terms of waiting and turnaround times,and *** experiments showed that the proposed algorithm gives better results.

关键词： Clustering CPU scheduling round robin turnaround time waiting time

Path planning for moving target tracking by fixed-wing UAV

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Defence Technology（防务技术） 2020年第4期16卷 811-824页

作者： Song-lin Liao Rong-ming Zhu Nai-qi Wu Tauqeer ahmed Shaikh mohamed Sharaf Almetwally m.mostafa School of Electro-mechanical Engineering Xidian UniversityXi'an 710071China Institute of Systems Engineering Macao University of Science and TechnologyTaipa999078Macao Electrical Engineering Department College of EngineeringKing Saud UniversityRiyadh 11421Saudi Arabia Industrial Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia College of Computer and Information Sciences King Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia Faculty of Engineering Alazhar University CairoEgypt

For the automatic tracking of unknown moving targets on the ground,most of the commonly used methods involve circling above the *** such a tracking mode,there is a moving laser spot on the target,which will bring trouble for cooperative manned *** this paper,we propose a new way of tracking,where an unmanned aerial vehicle(UAV) circles on one side of the tracked target.A circular path algorithm is developed for monitoring the relative position between the UAV and the target considering the real-time range and the bearing *** can determine the center of the new circular path if the predicted range between the UAV and the target does not meet the monitoring requirements.A transition path algorithm is presented for planning the transition path between circular paths that constrain the turning radius of the *** transition path algorithm can generate waypoints that meet the flight *** this paper,we analyze the entire method and detail the scope of *** formulate an observation angle as an evaluation index.A series of simulations and evaluation index comparisons verify the effectiveness of the proposed algorithms.

关键词： Bearing angle Fixed-wing UAV Laser designation moving target tracking Path planning

An Optimized Algorithm for CR-mImO Wireless Networks

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Computers, materials & Continua 2022年第4期71卷 697-715页

作者： Imran Khan Fahd N.Al-Wesabi marwa Obayya Anwer mustafa Hilal manar ahmed Hamza mohammed Rizwanullah Fahad ahmed Al-Zahrani Hirofumi Amano Samih m.mostafa Department of Electrical Engineering University of Engineering&TechnologyPeshawarPakistan Department of Computer Science King Khalid UniversityMuhayel AseerKSA Department of Biomedical Engineering College of EngineeringPrincess Nourah bint Abdulrahman UniversitySaudi Arabia Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia Computer Engineering Department Umm Al-Qura UniversityMecca24381Saudi Arabia Research Institute for Information Technology Kyushu UniversityFukuoka819-0395Japan Computer Science-mathematics Department Faculty of ScienceSouth Valley UniversityQena83523Egypt

With the rapid development of wireless communication technology,the spectrum resources are increasingly strained which needs optimal *** radio(CR)is one of the key technologies to solve this *** sensing not only includes the precise detection of the communication signal of the primary user(PU),but also the precise identification of its modulation type,which can then determine the a priori information such as the PU’service category,so as to use this information to make the cognitive user(CU)aware to discover and use the idle spectrum more effectively,and improve the spectrum *** sensing is the primary feature and core part of *** sensing algorithms includes energy detection,cyclostationary feature detection,matched filter detection,and so *** energy detection algorithm has a simple structure and does not require prior knowledge of the PU transmitter signal,but it is easily affected by noise and the threshold is not easy to *** combination of multiple-input multiple-output(mImO)with CR improves the spectral efficiency and multipath fading *** best utilize the PU spectrum while minimizing the overall transmit power,an iterative technique based on semidefinite programming(SDP)and minimum mean squared error(mmSE)is ***,this article proposed a new method for max-min fairness *** compared to existing algorithms,the simulation results show that the proposed algorithms perform better in terms of total transmitted power and signal-tointerference plus noise ratio(SINR).Furthermore,the proposed algorithm effectively improved the system performance in terms of number of iterations,interference temperature threshold and balance SINR level which makes it superior over the conventional schemes.

关键词： Cognitive radio spectrum utilization bandwidth primary user

A Perfect Knob to Scale Thread Pool on Runtime

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Computers, materials & Continua 2022年第7期72卷 1483-1493页

作者： Faisal Bahadur Arif Iqbal Umar Insaf Ullah Fahad Algarni muhammad Asghar Khan Samih m.mostafa Department of Information Technology Hazara UniversityMansehra21300Pakistan Hamdard Institute of Engineering and Technology Islamabad CampusPakistan College of Computing and Information Technology The University of BishaBishaSaudi Arabia Faculty of Computers and Information South Valley UniversityQena83523Egypt

Scalability is one of the utmost nonfunctional requirement of server applications,because it maintains an effective performance parallel to the large fluctuating and sometimes unpredictable *** order to achieve scalability,thread pool system(TPS)has been used extensively as a middleware service in server *** size of thread pool is the most significant factor,that affects the overall performance of *** the optimal size of thread pool dynamically on runtime is a challenging *** most widely used and simple method to tackle this problem is to keep the size of thread pool equal to the request rate,i.e.,the frequencyoriented thread pool(FOTP).The FOTPs are the most widely used TPSs in the industry,because of the implementation simplicity,the negligible overhead and the capability to use in any ***,the frequency-based schemes only focused on one aspect of changes in the load,and that is the fluctuations in request *** request rate alone is an imperfect knob to scale thread ***,this paper presents a workload profiling based FOTP,that focuses on request size(service time of request)besides the request rate as a knob to scale thread pool on runtime,because we argue that the combination of both truly represents the load fluctuation in server-side *** evaluated the results of the proposed system against state of the art TPS of Oracle Corporation(by a client-server-based simulator)and concluded that our system outperformed in terms of both;the response times and throughput.

关键词： Scalability performance middleware workload profiling multithreading thread pool

Effects of Avian Wings Color Patterns on Their Flight Performance:Experimental and Computational Studies

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Journal of Bionic Engineering 2023年第2期20卷 683-710页

作者： ahmed Aboelezz Brenden Herkenhoff mostafa Hassanalian Department of mechanical Engineering New Mexico Institute of Mining and TechnologySocorroNM87801USA

There are many theories behind the colors of a bird’s *** of these theories point to the color’s purpose to attract mates and hide from *** recent investigations concluded that the dark colors of birds help in reducing the drag force during flight.A new theory is presented in the current research,which states that a bird's dark color not only reduces the drag,but the color pattern also improves the overall flight performance,and each color pattern has a different type of flight performance *** difference in improvement is a result of variation in hot and cold surfaces on the bird skin as a result of the variation between light and dark feather *** prove this new theory,thermal images were captured of real bird wings under the effect of infrared ***,a novel wind tunnel wing with the ability to adjust the temperature in desired locations and patterns on the wing’s surface was manufactured and tested to evaluate the effect of aerodynamics forces as a function in the surface temperature and the hot–cold *** collected data from this wing showed potential flight efficiency improvements of 20%,comparing the lift-to-drag ratio for specific heating cases,which could increase the flight *** considering lift and drag,there were specific heating cases with corresponding angles of attack in which these parameters improved by up to 20%and 7%,*** heating cases could increase the lift at a low angle of attack,which is helpful in cruise flight performance,while some cases could increase the maximum lift coefficient by 6%.This is very helpful in lowering stall and the minimum flight ***,some cases could increase the lift-to-drag ratio,which led to an increase in the flight *** better understand the effect of the various patterns,computational fluid dynamics(CFD)simulations were conducted on the *** new theory was proved based on the CFD results and verified through the success

关键词： Aerodynamic loads CFD Drag Heated boundary layer Surface temperature

An Optimal Framework for SDN Based on Deep Neural Network

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Computers, materials & Continua 2022年第10期73卷 1125-1140页

作者： Abdallah Abdallah mohamad Khairi Ishak Nor Samsiah Sani Imran Khan Fahad RAlbogamy Hirofumi Amano Samih m.mostafa Department of Industrial Engineering School of Applied Technical Sciences German Jordanian UniversityAmman35247Jordan School of Electrical and Electronic Engineering Universiti Sains MalaysiaNibong Tebal14300Malaysia Center for Artificial Intelligence Technology Faculty of Information Science and TechnologyThe National University of Malaysia(UKM)Bangi43600SelangorMalaysia Department of Electrical Engineering University of Engineering and TechnologyPeshawar814Pakistan Turabah University College Computer Sciences ProgramTaif UniversityTaif21944Saudi Arabia Research Institute for Information Technology Kyushu UniversityFukuoka819-0395Japan Computer Science-mathematics Department Faculty of ScienceSouth Valley UniversityQena83523Egypt

Software-defined networking(SDN)is a new paradigm that promises to change by breaking vertical integration,decoupling network control logic from the underlying routers and switches,promoting(logical)network control centralization,and introducing network ***,the controller is similarly vulnerable to a“single point of failure”,an attacker can execute a distributed denial of service(DDoS)attack that invalidates the controller and compromises the network security in *** address the problem of DDoS traffic detection in SDN,a novel detection approach based on information entropy and deep neural network(DNN)is *** approach contains a DNN-based DDoS traffic detection module and an information-based entropy initial inspection *** initial inspection module detects the suspicious network traffic by computing the information entropy value of the data packet’s source and destination Internet Protocol(IP)addresses,and then identifies it using the DDoS detection module based on *** assaults were found when suspected irregular traffic was *** reveal that the algorithm recognizes DDoS activity at a rate of more than 99%,with a much better accuracy *** false alarm rate(FAR)is much lower than that of the information entropy-based detection ***,the proposed framework can shorten the detection time and improve the resource utilization efficiency.

关键词： Deep neural network computer networks data security optimization

Experimental and mathematical modeling of Cr(Ⅵ) removal using nano-magnetic Fe3O4-coated perlite from the liquid phase

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1582-1590页

作者： Ismail m.ahmed mostafa m.Hamed Sayed S.metwally Chemistry Department College of ScienceJouf UniversitySkakaSaudi Arabia Hot Laboratories and Waste management Center Atomic Energy Authority13759 CairoEgypt

modification of perlite using nano-magnetic iron oxide was implemented to produce nano-magneticFe3O4-coated perlite composite(Fe3O4/Perlite).The prepared composite was characterized using Scanning Electron microscopy,Fourier-Transform Infrared spectroscopy and Powder X-ray *** potentiality of both perlite and Fe3O4/Perlite composite to eliminate Cr(VI)from the environmentally relevant water was *** influence of main factors which could affect the adsorption was studied including;pH of medium,shaking time and Cr(VI)ions *** experimental outcome demonstrated that the modification of perlite by nano-magnetic Fe3O4 showed a significantly enhanced Cr(VI)removal efficiency relative to that of unmodified *** the kinetic studies,the experimental data fitted well with the pseudo-second-order ***,it proposes that Langmuir isotherm is more adequate than the Freundlich isotherm for both perlite and modified *** results recommended that Fe3O4/Perlite composite had a great potential as an economic and efficient adsorbent of Cr(VI)from contaminated water,which has huge application potential.

关键词： Nano-magnetic Composite Kinetics Isotherm Perlite Adsorption