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The Multi-scale Method for Solving Nonlinear Time Space Fractional Partial Differential Equations

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 299-306页

作者： Hossein Aminikhah Mahdieh Tahmasebi mahmoud Mohammadi Roozbahani the Department of Applied Mathematics University of Guilan the Department of Applied Mathematics Faculty of Mathematical SciencesTarbiat Modares University

In this paper, we present a new algorithm to solve a kind of nonlinear time space-fractional partial differential equations on a finite domain. The method is based on B-spline wavelets approximations, some of these functions are reshaped to satisfy on boundary conditions exactly. The Adams fractional method is used to reduce the problem to a system of equations. By multiscale method this system is divided into some smaller systems which have less computations. We get an approximated solution which is more accurate on some subdomains by combining the solutions of these systems. Illustrative examples are included to demonstrate the validity and applicability of our proposed technique, also the stability of the method is discussed.

关键词： Adams fractional method B-spline wavelets multi-scale method nonlinear fractional partial differential equations

Three-dimensional spread analysis of a Dengue disease model with numerical season control

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International Journal of Biomathematics 2021年第8期14卷 157-213页

作者： Fereshte Gazori mahmoud Hesaaraki Department of Mathematical Sciences Sharif University of TechnologyAzadi StreetTehranIran Faculty of Mathematical Sciences Sharif University of TechnologyAzadi StreetTehranIran

Dengue is among the most important infectious diseases in the *** main contribution of our paper is to present a mixed system of partial and ordinary differential *** combined model is a generalization of the two presented mathematical models(*** Araujo,*** and ***,An analysis of a mathematical model describing the geographic spread of dengue disease,***.444(2016)298–325)and(***,***,***,*** and ***,Optimal control of a malaria model with asymptomatic class and superinfection,***.288(2017)94–108),describing the geographic spread of dengue *** model has the ability to consider the possibility of asymptomatic infection,which leads to investigate the effect of dengue asymptomatic individuals on disease dynamics and to go into the possibility of superinfection of asymptomatic *** the light of considering these factors,as well as the movements of human and mature female mosquitoes,more realistic modeling of dengue disease can be *** present a mathematical analysis and show the global existence of a unique non-negative solution to this model and then establish ways to control dengue disease using numerical simulations and sensitivity analysis of model parameters(which are related to the contact rates and death rate of winged mosquitoes).To show different biological behaviors,we provide several numerical results,showing the role of parameters in controlling dengue disease *** our numerical simulations,it can also be concluded that local control of dengue transmission can be done at a lower cost.

关键词： Dengue virus nonlinear advection-diffusion system holder spaces global existence

A Numerical Efficient Technique for the Solution of Susceptible Infected Recovered Epidemic Model

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Computer Modeling in Engineering & Sciences 2020年第8期124卷 477-491页

作者： Muhammad Shoaib Arif Ali Raza Kamaleldin Abodayeh Muhammad Rafiq Mairaj Bibi amna Nazeer Stochastic Analysis and Optimization Research Group Department of MathematicsAir UniversityPAF Complex E-9Islamabad44000Pakistan Department of Mathematics National College of Business Administration and EconomicsLahorePakistan Department of Mathematics and General Sciences Prince Sultan UniversityRiyadhSaudi Arabia Faculty of Engineering University of Central PunjabLahorePakistan Department of Mathematics Comsats University IslamabadIslamabadPakistan

The essential features of the nonlinear stochastic models are positivity,dynamical consistency and *** features have a significant role in different fields of computational biology and many *** aim of our paper,to achieve the comparison analysis of the stochastic susceptible,infected recovered epidemic *** stochastic modelling is a realistic way to study the dynamics of compartmental modelling as compared to deterministic *** effect of reproduction number has also observed in the stochastic susceptible,infected recovered epidemic *** comparison analysis,we developed some explicit stochastic techniques,but they are the time-dependent *** implicitly driven explicit technique has developed for the stochastic susceptible,infected recovered epidemic *** the support,some theorems and graphical illustration has ***,the time efficiency of this method makes it easy to find the solution of the stochastic *** comparison with other techniques shows the efficacy and reliability of the designed technique.

关键词： Epidemiolocal model stochastic differential equations stochastic techniques convergence analysis

Distributed H2/H∞ Filter Design for Discrete-Time Switched Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 158-168页

作者： Nezar M.Alyazidi Magdi S.mahmoud Systems Engineering Department King Fahd University for Petroleum and Minerals

This paper addresses an infinite horizon distributed H2/H∞ filtering for discrete-time systems under conditions of bounded power and white stochastic signals. The filter algorithm is designed by computing a pair of gains namely the estimator and the coupling. Herein, we implement a filter to estimate unknown parameters such that the closed-loop multi-sensor accomplishes the desired performances of the proposed H2 and H∞ schemes over a finite horizon. A switched strategy is implemented to switch between the states once the operation conditions have changed due to disturbances. It is shown that the stability of the overall filtering-error system with H2/H∞ performance can be established if a piecewise-quadratic Lyapunov function is properly constructed. A simulation example is given to show the effectiveness of the proposed approach.

关键词： Bounded power stochastic disturbance discretetime systems H2/H∞ filtering infinite horizon multi-sensor switched systems

Fundamental Issues in Networked Control Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 902-922页

作者： Magdi S.mahmoud a Mutaz M.Hamdan the systems engineering department king fahd university of petroleum and minerals

Abstract--This paper provides a survey on modeling and theories of networked control systems （NCS）. In the first part, modeling of the different types of imperfections that affect NCS is discussed. These imperfections are quantization errors, packet dropouts, variable sampling/transmission intervals, vari- able transmission delays, and communication constraints. Then follows in the second part a presentation of several theories that have been applied for controlling networked systems. These theories include： input delay system approach, Markovian system approach, switched system approach, stochastic system approach, impulsive system approach, and predictive control approach. In the last part, some advanced issues in NCS including decentral- ized and distributed NCS, cloud control system, and co-design of NCS are reviewed. Index Terms--Decentralized networked control systems （NCS）, distributed networked control systems, network constraints, net- worked control system, quantization, time delays.

关键词： Decentralized networked control systems(NCS) distributed networked control systems network constraints networked control system quantization time delays

Estimating the impact of azimuth-angle variations on photovoltaic annual energy production

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Clean Energy 2019年第1期3卷 47-58页

作者： mahmoud Dhimish Santiago Silvestre Laboratory of Photovoltaics University of HuddersfieldQueensgateHD13DHHuddersfieldUK MNT Group Electronic Engineering DepartmentUniversitat Politecnica de Catalunya(UPC)BarcelonaTechC/Jordi Girona 1-3Campus Nord UPC08034 BarcelonaSpain

The performance of a photovoltaic(PV)installation is affected by its tilt and azimuth angles,because these parameters change the amount of solar energy absorbed by the surface of the PV ***,this paper demonstrates the impact of the azimuth angle on the energy production of PV *** different PV sites were studied,where the first comprises PV systems installed at-13°,-4°,+12°and+21°azimuth angles in different geographical locations,whereas the second PV site included adjacent PV systems installed at-87°,-32°,+2°and+17°azimuth *** the investigated PV sites were located in Huddersfield,*** summary,the results indicate that PV systems installed between-4°and+2°presented the maximum energy production over the last 4 years,while the worst energy generation were observed for the PV system installed at an azimuth angle of-87°.Finally,the probability projections for all observed azimuth angles datasets have been *** PV systems are affected by various environmental conditions such as fluctuations in the wind,humidity,solar irradiance and ambient temperature,ultimately,these factors would affect the annual energy generation of the PV *** that reason,we have analysed the disparities and the probability of the annual energy production for multiple PV systems installed at different azimuth angles ranging from-90°to+90°degrees,and affected by different environmental *** analyses are based on the cumulative density function modelling technique as well as the normal distribution function.

关键词： photovoltaics azimuth angle energy production CDF modelling

Study on histo-biochemical biomarkers of chromium induced toxicity in Labeo rohita

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Emerging Contaminants 2023年第1期9卷 68-75页

作者： amna Chaudhary Komal gul Javaid Erum Bughio Nauman Faisal Department of Fisheries and Aquaculture Faculty of Fisheries and WildlifeUniversity of Veterinary and Animal SciencesLahorePakistan Department of Poultry Production Faculty of Animal Production and TechnologyShaheed Benazir Bhutto University of Veterinary and Animal SciencesSakrandPakistan

Aquatic environment gets highly polluted due to the presence of heavy metals,which are usually discharged into water bodies because of rapid *** main purpose of this study is to evaluate the effects of chromium toxicity on histo-biochemical biomarkers of Labeo rohita.A total of 240 randomly selected fish were distributed into four aquaria(n=20).Three groups designated as T_(1),T_(2) and T_(3) were exposed with 1/3rd,1/5th and 1/10th of LC_(50) of chromium chloride,and the fourth group was chromium-free control(T0).Results showed a significant(p<0.05)decrease in blood parameters such as hematocrit,red blood cells,hemoglobin,mean cell hemoglobin and *** contrast,mean cell volume and white blood cell values increased *** results obtained by comet assay showed that DNA damage was increased significantly(p<0.05)in chromium-exposed groups compared to the *** the histopathological level,observed alterations in the gill tissues are degeneration of epithelium,fusion of secondary lamellae,lamellar curling,hypertrophy,telangiectasis and oedema,while in the liver is necrosis,dilation of the vein,congestion of blood vessels,hepatocytes degeneration,melano-macrophage centers,pigmentation and *** the kidney,histological alterations such as glomerular destruction,necrosis,damaged blood vessels,oedema and pigmentation were *** results suggest that chromium has the ability to bring variations DNA integrity,histopathology and blood of Labeo rohita.

关键词： Heavy metals Biomarkers Chromium Histopathology DNA damage Labeo rohita

VISCOMETRIC INVESTIGATIONS OF POLYVINYLPYRROLIDONE IN MIXED SOLVENTS AND WITH VARYING TEMPERATURE

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Chinese Journal of Polymer Science 2005年第4期23卷 367-371页

作者： Omar Melad Omar abu-Tiem Rajai Baraka Chemistry Department

The viscosity behavior of polyvinylpyrrolidone(PVP)has been determined at 25℃ in mixed solvents comprising water/dimethylformamide(DMF)and water/methanol(MeOH).Analysis of the data has considered the PVP as being both host and guest polymer in *** intrinsic viscosity of PVP in DMF is higher than in water and in MeOH,but also increases in a mixed solvent with high water content because of the effect of polymer-solvent *** was also found that the intrinsic viscosity of PVP at finite concentration,[η_(pvp)]_c decreases with an increase in the concentration of PVP in *** viscosity behavior of PVP in a mixed solvent is affected by the concentration-dependent intermolecular excluded volume effect,which can be quantitatively expressed by the parameter,b_Y,which reflects the shrinkage of PVP chain coils,resulting in a decrease of[η_(pvp)]_*** effect of temperature on the viscosity behavior of PVP in MeOH shows that the interaction parameter increases up to a maximum value,and then decreases after a certain temperature.

关键词： Polyvinylpyrrolidone Intermolecular excluded volume effect Intrinsic viscosity

Simulation of Vortex-Induced Vibrations of A Cylinder Using ANSYS CFX

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China Ocean Engineering 2014年第4期28卷 541-556页

作者： abu Bakar IZHAR Arshad Hussain QURESHI Shahab KHUSHNOOD University of Engineering & Technology Lahore Pakistan University of Engineering & Technology Taxila Pakistan

In this paper, vortex-induced vibrations of a cylinder are simulated by use of ANSYS CFX simulation code. The cylinder is treated as a rigid body and transverse displacements are obtained by use of a one degree of freedom spring damper system. 2-D as well as 3-D analysis is performed using air as the fluid. Reynolds number is varied from 40 to 16000 approx., covering the laminar and turbulent regimes of flow. The experimental results of （Khalak and Williamson, 1997） and other researchers are used for validation purposes. The results obtained are comparable.

关键词： vortex-induced vibrations ANSYS CFX flow induced vibrations fluid structure interaction