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A numerical study by using the Chebyshev collocation met hod for a problem of biological invasion: Fractional Fisher equation A numerical study by using the Chebyshev collocation met hod for a problem of biological invasion: Fractional Fisher equation

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International Journal of Biomathematics 2018年第8期11卷 71-85页

作者： mohamed m. Khader Khaled m. saad Department of mathematics and Statistics College of Science Al Imam Mohammad Ibn Saud Islamic University (IMSIU) Riyadh Saudi Arabia Department of mathematics Faculty of Science Benha University Benha Egypt Department of mathematics College of Arts and Sciences Najran University Najran Saudi Arabia Department of mathematics Faculty of Applied Science Taiz University Taiz Yemen

In this paper, an efficient numerical method is introduced for solving the fractional (Caputo sense) Fisher equation. We use the spectral collocation method which is based upon Chebyshev approximations. The properties of Chebyshev polynomials of the third kind are used to reduce the proposed problem to a system of ODEs, which is solved by the finite difference method (FDm). Some theorems about the convergence analysis are stated and proved. A numerical simulation is given and the results are compared with the exact solution.

关键词： Fractional Fisher equation FDm Chebyshev polynomials convergence analysis

Rooted Tree Optimization for Wind Turbine Optimum Control Based on Energy Storage System

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Computers, materials & Continua 2023年第2期74卷 3977-3996页

作者： Billel meghni Afaf Benamor Oussama Hachana Ahmad Taher Azar Amira Boulmaiz Salah saad El-Sayed m.El-kenawy Nashwa Ahmad Kamal Suliman mohamed Fati Naglaa K.Bahgaat Department of Electrical Engineering Badji Mokhtar UniversityLSEM LaboratoryAnnaba23000Algeria Department of Electrical Engineering Biskra UniversityLGEB LaboratoryBiskra07000Algeria Department of Drilling and Rig mechanics Ksadi Merbah UniversityOuargla30000Algeria College of Computer and Information Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia Faculty of Computers and Artificial Intelligence Benha UniversityBenha13518Egypt Department of Electronics University of Badji MokhtarLERICA LaboratoryAnnaba23000Algeria Delta Higher Institute for Engineering&Technology(DHIET) Mansoura35511Egypt Faculty of Artificial Intelligence Delta University for Science and TechnologyMansoura35712Egypt Faculty of Engineering Cairo UniversityGiza12613Egypt Department of Communications and Electronics Engineering Faculty of EngineeringCanadian International College(CIC)ElShiekh ZayedEgypt

The integration of wind turbines(WTs)in variable speed drive systems belongs to the main factors causing lowstability in electrical ***,in order to avoid this issue,WTs hybridization with a storage system is a *** paper investigates WT system operating at variable *** system contains of a permanent magnet synchronous generator(PmSG)supported by a battery storage system(BSS).To enhance the quality of active and reactive power injected into the network,direct power control(DPC)scheme utilizing space-vector modulation(SVm)technique based on proportional-integral(PI)control is ***,to improve the rendition of this method(DPC-SVm-PI),the rooted tree optimization technique(RTO)algorithm-based controller parameter identification is used to achieve PI optimal *** compare the performance ofRTO-based controllers,they were implemented and tested along with some other popular controllers under different working *** obtained results have shown the supremacy of the suggested PIRTO algorithm compared to competing controllers regarding total harmonic distortion(THD),overshoot percentage,settling time,rise time,average active power value,overall efficiency,and active power steadystate error.

关键词： Rooted tree optimization(RTO)method direct power control(DPC) wind turbine(WT) proportional integral(PI) PmSG

On Special Curves According to Darboux Frame in the Three Dimensional Lorentz Space

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Computers, materials & Continua 2018年第3期54卷 229-249页

作者： H.S.Abdel-Aziz m.Khalifa saad math.Dept. Faculty of ScienceSohag University82524 SohagEgypt. math.Dept. Faculty of ScienceIslamic University of Madinah170 El MadinahKSA

In the light of great importance of curves and their frames in many differentbranches of science, especially differential geometry as well as geometric properties andthe uses in various fields, we are interested here to study a special kind of curves calledSmarandache curves in Lorentz 3-space. Then, we present some characterizations for thesecurves and calculate their Darboux invariants. moreover, we classify TP, TU, PU andTPU-Smarandache curves of a spacelike curve according to the causal character of thevector, curve and surface used in the study. Besides, we give some of differential geometricproperties and important relations between that curves. Finally, to demonstrate ourtheoretical results a computational example is given with graph.

关键词： Smarandache curves spacelike curve timelike surface Darboux frame

Natural Convection and Thermal Radiation Influence on Nanofluid Flow over a Nonlinearly Stretching Sheet

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Journal of Applied mathematics and Physics 2022年第11期10卷 3301-3315页

作者： Emad m. Abo-Eldahab Rasha Adel Yasmin m. saad Department of mathematics Faculty of Science Helwan University Cairo Egypt Basic Science Department School of Engineering Canadian International Collage Giza Egypt

This paper studies the effects of Natural convection and Thermal radiation on nanofluid over a non-linearly stretching sheet. The governing equation of nonlinear partial differential equations of the flow is transformed to nonlinear ordinary differential equations by using similarity transformation, earlier than being solved numerically through a Rung-Kutta-Fehlberg method with shooting technique. The numerical results have been obtained for The influence of Brownian motion number (Nb), thermophoresis number (Nt), Grashof number (Gr), Lewis number (Le), stretching parameter (n), and thermal radiation parameter (Ra) on the velocity, temperature, and nanoparticles concentration profiles are shown graphically.

关键词： Nanofluid Stretching Sheet Thermal Radiation Free Convection

A Review on Primary and Secondary Controls of Inverter-interfaced microgrid

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Journal of modern Power Systems and Clean Energy 2021年第5期9卷 969-985页

作者： Kafeel Ahmed mehdi Seyedmahmoudian saad mekhilef N.m.mubarak Alex Stojcevski School of Software and Electrical Engineering Swinburne University of TechnologyVIC 3122VictoriaAustralia Power Electronics and Renewable Energy Research Laboratory Department of Electrical EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Department of Chemical Engineering Faculty of Engineering and ScienceCurtin University of Technology98009 SarawakMalaysia

The demand of electricity and environmental issues associated with conventional power generation plants are increasing *** technology has transformed the conventional power system through the integration of distributed generation(DG).With the help of modern power electronic technology,the conventional power system is able to support the integration of DGs based on renewable energy sources(RESs).The systematic combination of DGs with energy storage system forms a microgrid(mG),which can operate in islanded mode or grid-connected *** intermittent nature of RES and varying load pose substantial obstacles such as voltage and frequency instability,and the unreliability of *** feeder impedances and non-linear loads are considered as present challenges in mG *** control has been useful in undertaking solutions to these *** paper covers the deep insight of different control methods applied at the primary and secondary control levels in hierarchical *** primary control,the classification based on droop and non-droop controls is *** virtual synchronization machine(VSm)based control method is *** and frequency restoration control and economical operations at decentralized and centralized secondary control are analyzed in *** on the existing literature,critical discussion on mG control and future trends are also presented to provide future research perspectives.

关键词： Distributed generation(DG) hierarchical control droop control non-droop control inverter

Control of animal brucellosis: the malaysian experience

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Asian Pacific Journal of Tropical medicine 2016年第12期9卷 1111-1115页

作者： m.Zamri-saad m.I.Kamarudin Research Centre for Ruminant Diseases Faculty of Veterinary MedicineUniversiti Putra Malaysia Department of Veterinary Services malaysia Ministry of Agriculture and Agro-based Industry

Brucellosis is a zoonotic disease characterized by reproductive failure in animals and undulent fever in humans. In cattle, it is caused by Brucella abortus while in goats by Brucella melitensis, the main cause of brucellosis in humans. Brucellosis in livestock has been associated with importation of animals from breeder herd of unknown disease status. The prevalence of bovine brucellosis Brucella abortus in 2014 ranged between 1%-2% in Thailand and Indonesia, and 4%-5% in malaysia and myanmar. Prevalence of goat brucellosis Brucella melitensis is approximately 1% in malaysia and Thailand. ‘Test-and-slaughter' is the general policy against brucellosis adopted by most ASEAN countries to eradicate the disease. Under this program, the Rose Bengal Plate Test(RBPT) is used as the screening test to identify infected farm/herd while the Complement Fixation Test(CFT) is the confirmatory test. The test-and-slaughter eradication strategy that was implemented since 1979 had managed to keep the prevalence rate to less than 5%, from 3.3% in 1979, 0.23% in 1988, 1% in 1998 and 5% in 2016. The test-and-slaughter program seemed effective in reducing the prevalence of brucellosis but was unable to eradicate the disease due to several factors, which include failure to locate and identify the remaining affected animals and to control their movement, importation of breeder animals from non-brucellosis free countries and lack of participation by the farmers following unrealiable test results. To support the eradication policy, research activities since 1980 s have suggested combinations of serological tests to improve diagnosis while surveillance should be focused on hotspots areas. The prevalence can be further reduced by strictly sourcing breeder animals from brucella-free areas or countries.

关键词： Brucellosis Animal Control

Dielectric Behavior of modified Cellulose

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Journal of materials Science & Technology 1999年第2期15卷 164-168页

作者： El-Henawii, S.A. saad, S.m. El-Anwar, I.m. Faculty of Science Helwan University Egypt Chemistry Department Faculty of Science Al-Azhar University Egypt Physical Chemistry Unit of the N.R.C Egypt

The dielectric constants and the dielectric loss, as well as the activation energy of dielectric relaxation of silylated cellulose were measured within the frequency range 10**5 to 10**7 Hz and the temperature range from 10 to 50 degree C. The test samples were activated cellulose with ethylene diamine, with sodium hydroxide and inactivated cellulose before and after silylation. The measurements were carried out using a multi-deka-meter. Cellulose molecules are more activated by treatment with ethylene diamine than with sodium hydroxide. Generally, silylation causes a marked decrease of the dielectric constant and dielectric loss, meanwhile the silylated samples are affected with the pretreatment of linters with sodium hydroxide and ethylene diamine. (Edited author abstract) 28 Refs.

关键词： Cellulose

Blockchain and IIoT Enabled Solution for Social Distancing and Isolation management to Prevent Pandemics

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Computers, materials & Continua 2023年第7期76卷 687-709页

作者： muhammad saad maaz Bin Ahmad muhammad Asif muhammad Khalid Khan Toqeer mahmood Elsayed Tag Eldin Hala Abdel Hameed College of Computing and Information Sciences Karachi Institute of Economics&TechnologyKarachiPakistan Department of Computer Science Lahore Garrison UniversityLahorePakistan Department of Computer Science National Textile UniversityFaisalabad37610Pakistan Faculty of Engineering and Technology Future University in Egypt New Cairo11835Egypt Faculty of Computer and Information Systems Fayoum UniversityFaiyumEgypt Khaybar Applied College Taibah UniversityMedinaSaudi Arabia

Pandemics have always been a nightmare for humanity,especially in developing *** lockdowns are considered one of the effective ways to deal with spreading such ***,developing countries cannot afford such solutions because these may severely damage the country’s ***,this study presents the proactive technological mechanisms for business organizations to run their standard business processes during pandemic-like situations *** novelty of this study is to provide a state-of-the-art solution to prevent pandemics using industrial internet of things(IIoT)and blockchain-enabled *** to existing studies,the immutable and tamper-proof contact tracing and quarantine management solution is *** use of advanced technologies and information security is a critical area for practitioners in the internet of things(IoT)and corresponding ***,this study also emphasizes information security,end-to-end solution,and experimental ***,a wearable wristband is proposed,incorporating 4G-enabled ultra-wideband(UWB)technology for smart contact tracing mechanisms in industries to comply with standard operating procedures outlined by the world health organization(WHO).Secondly,distributed ledger technology(DLT)omits the centralized dependency for transmitting contact tracing ***,a privacy-preserving tracing mechanism is discussed using a public/private key cryptography-based authentication ***,based on geofencing techniques,blockchain-enabled machine-to-machine(m2m)technology is proposed for quarantine *** step-by-step methodology and test results are proposed to ensure contact tracing and quarantine *** existing research studies,the security aspect is also considered in the realm of *** practical implementation of the proposed solution also obtains the *** results indicate the successful implementation of blockchain-enabled contac

关键词： Blockchain contact tracing distributed ledger technology geo-fencing internet of things industrial internet of things isolation management social distancing ultra-wideband

On a new modified fractional analysis of Nagumo equation

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International Journal of Biomathematics 2019年第3期12卷 191-205页

作者： Khaled m.saad Sinan Deniz Dumitru Baleanu Department of mathematics College of Science and Arts Najran University P.O. Box 1988 Najran Saudi Arabia Department of Mathematics Faculty of Applied Science Taiz University P.O. Box 6169 Taiz Yemen Department of mathematics Faculty of Art and Sciences Manisa Celal Bayar University 45140 Manisa Turkey Department of mathematics Faculty of Sciences Cankaya University 06530 Ankara Turkey Institute of Space Sciences Magurele-Bucharest Romania

In this work, a new modified fractional form of the Nagumo equation has been presented and deeply analyzed. Using the Caputo–Fabrizio and Atangana–Baleanu time-fractional derivatives, classical Nagumo model is transformed to a new fractional version. The modified equation has been solved by using the homotopy analysis transform method. The convergence analysis has been also examined with the help of the so-called hh-curves and average residual error. Comparing the obtained approximate solution with the exact solution leaves no doubt believing that the proposed technique is very efficient and converges toward the exact solution very rapidly.

关键词： Nagumo equation nonlinear diffusion and convection homotopy analysis transform method Caputo-Fabrizio-Caputo derivative Atangana-Baleanu-Caputo time-fractional derivatives