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Recent Developments in Authentication Schemes Used in Machine-Type Communication Devices in Machine-to-Machine Communication: Issues and Challenges
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作者 Shafi Ullah Sibghat Ullah Bazai +9 位作者 Mohammad Imran Qazi Mudassar ilyas Abid Mehmood Muhammad Asim Saleem Muhmmad Aasim Rafique Arsalan Haider ilyas khan Sajid Iqbal Yonis Gulzar Kauser Hameed 《Computers, Materials & Continua》 SCIE EI 2024年第4期93-115,共23页
Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) ... Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) regularly share extensive data without human intervention while making all types of decisions. Thesedecisions may involve controlling sensitive ventilation systems maintaining uniform temperature, live heartbeatmonitoring, and several different alert systems. Many of these devices simultaneously share data to form anautomated system. The data shared between machine-type communication devices (MTCDs) is prone to risk dueto limited computational power, internal memory, and energy capacity. Therefore, securing the data and devicesbecomes challenging due to factors such as dynamic operational environments, remoteness, harsh conditions,and areas where human physical access is difficult. One of the crucial parts of securing MTCDs and data isauthentication, where each devicemust be verified before data transmission. SeveralM2Mauthentication schemeshave been proposed in the literature, however, the literature lacks a comprehensive overview of current M2Mauthentication techniques and the challenges associated with them. To utilize a suitable authentication schemefor specific scenarios, it is important to understand the challenges associated with it. Therefore, this article fillsthis gap by reviewing the state-of-the-art research on authentication schemes in MTCDs specifically concerningapplication categories, security provisions, and performance efficiency. 展开更多
关键词 AUTHENTICATION cyber security internet of things machine-type communication devices machine-to-machine communication
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Extended Deep Learning Algorithm for Improved Brain Tumor Diagnosis System
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作者 M.Adimoolam K.Maithili +7 位作者 N.M.Balamurugan R.Rajkumar S.Leelavathy Raju Kannadasan Mohd Anul Haq ilyas khan ElSayed M.Tag El Din Arfat Ahmad khan 《Intelligent Automation & Soft Computing》 2024年第1期33-55,共23页
At present,the prediction of brain tumors is performed using Machine Learning(ML)and Deep Learning(DL)algorithms.Although various ML and DL algorithms are adapted to predict brain tumors to some range,some concerns st... At present,the prediction of brain tumors is performed using Machine Learning(ML)and Deep Learning(DL)algorithms.Although various ML and DL algorithms are adapted to predict brain tumors to some range,some concerns still need enhancement,particularly accuracy,sensitivity,false positive and false negative,to improve the brain tumor prediction system symmetrically.Therefore,this work proposed an Extended Deep Learning Algorithm(EDLA)to measure performance parameters such as accuracy,sensitivity,and false positive and false negative rates.In addition,these iterated measures were analyzed by comparing the EDLA method with the Convolutional Neural Network(CNN)way further using the SPSS tool,and respective graphical illustrations were shown.The results were that the mean performance measures for the proposed EDLA algorithm were calculated,and those measured were accuracy(97.665%),sensitivity(97.939%),false positive(3.012%),and false negative(3.182%)for ten iterations.Whereas in the case of the CNN,the algorithm means accuracy gained was 94.287%,mean sensitivity 95.612%,mean false positive 5.328%,and mean false negative 4.756%.These results show that the proposed EDLA method has outperformed existing algorithms,including CNN,and ensures symmetrically improved parameters.Thus EDLA algorithm introduces novelty concerning its performance and particular activation function.This proposed method will be utilized effectively in brain tumor detection in a precise and accurate manner.This algorithm would apply to brain tumor diagnosis and be involved in various medical diagnoses aftermodification.If the quantity of dataset records is enormous,then themethod’s computation power has to be updated. 展开更多
关键词 Brain tumor extended deep learning algorithm convolution neural network tumor detection deep learning
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Large Scale Fish Images Classification and Localization using Transfer Learning and Localization Aware CNN Architecture 被引量:1
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作者 Usman Ahmad Muhammad Junaid Ali +7 位作者 Faizan Ahmed khan Arfat Ahmad khan ArifUr Rehman Malik Muhammad Ali Shahid Mohd Anul Haq ilyas khan Zamil SAlzamil Ahmed Alhussen 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期2125-2140,共16页
Building an automatic fish recognition and detection system for largescale fish classes is helpful for marine researchers and marine scientists because there are large numbers of fish species.However,it is quite diffi... Building an automatic fish recognition and detection system for largescale fish classes is helpful for marine researchers and marine scientists because there are large numbers of fish species.However,it is quite difficult to build such systems owing to the lack of data imbalance problems and large number of classes.To solve these issues,we propose a transfer learning-based technique in which we use Efficient-Net,which is pre-trained on ImageNet dataset and fine-tuned on QuT Fish Database,which is a large scale dataset.Furthermore,prior to the activation layer,we use Global Average Pooling(GAP)instead of dense layer with the aim of averaging the results of predictions along with having more information compared to the dense layer.To check the validity of our model,we validate our model on the validation set which achieves satisfactory results.Also,for the localization task,we propose an architecture that consists of localization aware block,which captures localization information for better prediction and residual connections to handle the over-fitting problem.Actually,the residual connections help the layer to combine missing information with the relevant one.In addition,we use class weights and Focal Loss(FL)to handle class imbalance problems along with reducing false predictions.Actually,class weights assign less weights to classes having fewer instances and large weights to classes having more number of instances.During the localization,the qualitative assessment shows that we achieve 57%Mean Intersection Over Union(IoU)on testing data,and the classification results show 75%precision,70%recall,78%accuracy and 74%F1-Score for 468 fish species. 展开更多
关键词 Underwater species transfer learning k-nearest neighbors global average pooling efficientnet
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Modifications of the Optimal Auxiliary Function Method to Fractional Order Fornberg-Whitham Equations
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作者 Hakeem Ullah Mehreen Fiza +3 位作者 ilyas khan Abd Allah A.Mosa Saeed Islam Abdullah Mohammed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期277-291,共15页
In this paper,we present a new modification of the newly developed semi-analytical method named the Optimal Auxilary Function Method(OAFM)for fractional-order equations using the Caputo operator,which is named FOAFM.T... In this paper,we present a new modification of the newly developed semi-analytical method named the Optimal Auxilary Function Method(OAFM)for fractional-order equations using the Caputo operator,which is named FOAFM.The mathematical theory of FOAFM is presented and the effectiveness of this method is proven by using it with well-known Fornberg-Whitham Equations(FWE).The FOAFM results are compared with other method results along with their exact solutions with the help of tables and plots to prove the validity of FOAFM.A rapidly convergent series solution is obtained from FOAFMand is validated by comparison with other results.The analysis proves that ourmethod is simply applicable,contains less computationalwork,and is rapidly convergent to the exact solution at the first iteration.A series solution to the problem is obtained with the help of FOAFM.The validity of FOAFM results is validated by comparing its results with the results available in the literature.It is observed that FOAFM is simply applicable,contains less computational work,and is fastly convergent.The convergence and stability are obtained with the help of optimal constants.FOAFM is very easy in applicability and provides excellent results at the first iteration for complex nonlinear initial/boundary value problems.FOAFM contains the optimal auxiliary constants through which we can control the convergence as FOAFM contains the auxiliary functions D_(1),D_(2),D_(3)...in which the optimal constants G_(1),G_(2),...and the control convergence parameters exist to play an important role in getting the convergent solution which is obtained rigorously.The computational work in FOAFM is less when compared to other methods and even a low-specification computer can do the computational work easily. 展开更多
关键词 FOAFM exact solutions FWE Caputo operator HPM
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Design and Analysis of Graphene Based Tunnel Field Effect Transistor with Various Ambipolar Reducing Techniques
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作者 Puneet Kumar Mishra Amrita Rai +5 位作者 Nitin Sharma Kanika Sharma Nitin Mittal Mohd Anul Haq ilyas khan ElSayed M.Tag El Din 《Computers, Materials & Continua》 SCIE EI 2023年第7期1309-1320,共12页
The fundamental advantages of carbon-based graphene material,such as its high tunnelling probability,symmetric band structure(linear dependence of the energy band on the wave direction),low effective mass,and characte... The fundamental advantages of carbon-based graphene material,such as its high tunnelling probability,symmetric band structure(linear dependence of the energy band on the wave direction),low effective mass,and characteristics of its 2D atomic layers,are the main focus of this research work.The impact of channel thickness,gate under-lap,asymmetric source/drain doping method,workfunction of gate contact,and High-K material on Graphene-based Tunnel Field Effect Transistor(TFET)is analyzed with 20 nm technology.Physical modelling and electrical characteristic performance have been simulated using the Atlas device simulator of SILVACO TCAD with user-defined material syntax for the newly included graphene material in comparison to silicon carbide(SiC).The simulation results in significant suppression of ambipolar current to voltage characteristics of TFET and modelled device exhibits a significant improvement in subthreshold swing(0.0159 V/decade),the ratio of Ion/Ioff(1000),and threshold voltage(-0.2 V with highly doped p-type source and 0.2 V with highly doped n-type drain)with power supply of 0.5 V,which make it useful for low power digital applications. 展开更多
关键词 GRAPHENE tunnel field effect transistor(TFET) band to band tunnelling subthreshold swing
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Mathematical Analysis of Novel Coronavirus (2019-nCov) Delay Pandemic Model 被引量:9
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作者 Muhammad Naveed Muhammad Rafiq +4 位作者 Ali Raza Nauman Ahmed ilyas khan Kottakkaran Sooppy Nisar Atif Hassan Soori 《Computers, Materials & Continua》 SCIE EI 2020年第9期1401-1414,共14页
In this manuscript,the mathematical analysis of corona virus model with time delay effect is studied.Mathematical modelling of infectious diseases has substantial role in the different disciplines such as biological,e... In this manuscript,the mathematical analysis of corona virus model with time delay effect is studied.Mathematical modelling of infectious diseases has substantial role in the different disciplines such as biological,engineering,physical,social,behavioural problems and many more.Most of infectious diseases are dreadful such as HIV/AIDS,Hepatitis and 2019-nCov.Unfortunately,due to the non-availability of vaccine for 2019-nCov around the world,the delay factors like,social distancing,quarantine,travel restrictions,holidays extension,hospitalization and isolation are used as key tools to control the pandemic of 2019-nCov.We have analysed the reproduction number𝐑𝐑𝐧𝐧𝐧𝐧𝐧𝐧𝐧𝐧of delayed model.Two key strategies from the reproduction number of 2019-nCov model,may be followed,according to the nature of the disease as if it is diminished or present in the community.The more delaying tactics eventually,led to the control of pandemic.Local and global stability of 2019-nCov model is presented for the strategies.We have also investigated the effect of delay factor on reproduction number𝐑R_(nCov).Finally,some very useful numerical results are presented to support the theoretical analysis of the model. 展开更多
关键词 2019-nCov delay model reproduction number stability analysis numerical results
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Multiple solutions of Cu-C6H9NaO7 and Ag-C6H9NaO7 nanofluids flow over nonlinear shrinking surface 被引量:3
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作者 Liaquat Ali LUND Zurni OMAR +1 位作者 ilyas khan Sumera DERO 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1283-1293,共11页
Model of Casson nanofluid flow over a nonlinear shrinking surface is considered.Model of Tiwari and Das is applied to nanofluid comprising of sodium alginate with copper and silver.The governing nonlinear equations in... Model of Casson nanofluid flow over a nonlinear shrinking surface is considered.Model of Tiwari and Das is applied to nanofluid comprising of sodium alginate with copper and silver.The governing nonlinear equations incorporating the effects of the viscous dissipation are transformed into boundary value problems (BVPs) of ordinary differential equations (ODEs) by using appropriate similarity transformations.The resulting equations are converted into initial value problems (IVPs) using the shooting method which are then solved by Runge-Kutta method of fourth order.In order to determine the stability of the dual solutions obtained,stability analysis is performed and discovered that the first (second) solution is stable (unstable) and physically realizable (unrealizable).Both the thickness of the thermal boundary layer as well as temperature increase when the Casson parameter (β) is increased in the second solution. 展开更多
关键词 Cu-C6H9NaO7 Ag-C6H9NaO7 shrinking surface dual solution stability analysis NANOFLUID
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A Structure Preserving Numerical Method for Solution of Stochastic Epidemic Model of Smoking Dynamics 被引量:4
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作者 Ali Raza Muhammad Rafiq +3 位作者 Nauman Ahmed ilyas khan Kottakkaran Sooppy Nisar Zafar Iqbal 《Computers, Materials & Continua》 SCIE EI 2020年第10期263-278,共16页
In this manuscript,we consider a stochastic smoking epidemic model from behavioural sciences.Also,we develop a structure preserving numerical method to describe the dynamics of stochastic smoking epidemic model in a h... In this manuscript,we consider a stochastic smoking epidemic model from behavioural sciences.Also,we develop a structure preserving numerical method to describe the dynamics of stochastic smoking epidemic model in a human population.The structural properties of a physical system include positivity,boundedness and dynamical consistency.These properties play a vital role in non-linear dynamics.The solution for nonlinear stochastic models necessitates the conservation of these properties.Unfortunately,the aforementioned properties of the model have not been restored in the existing stochastic methods.Therefore,it is essential to construct a structure preserving numerical method for a reliable analysis of stochastic smoking model.The usual explicit stochastic numerical methods are time-dependent and violate most of the structural properties.In this work,we have developed the implicitly driven explicit method for the solution of stochastic smoking model.It is also proved that the newly developed method sustains all the aforementioned properties of the system.Finally,the convergence analysis of the newly developed method and graphical illustrations are presented. 展开更多
关键词 Smoking model stochastic numerical techniques CONVERGENCE
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Design of Computer Methods for the Solution of Cervical Cancer Epidemic Model 被引量:3
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作者 Ali Raza Muhammad Rafiq +4 位作者 Dalal Alrowaili Nauman Ahmed ilyas khan Kottakkaran Sooppy Nisar Muhammad Mohsin 《Computers, Materials & Continua》 SCIE EI 2022年第1期1649-1666,共18页
Nonlinear modelling has a significant role in different disciplines of sciences such as behavioral,social,physical and biological sciences.The structural properties are also needed for such types of disciplines,as dyn... Nonlinear modelling has a significant role in different disciplines of sciences such as behavioral,social,physical and biological sciences.The structural properties are also needed for such types of disciplines,as dynamical consistency,positivity and boundedness are the major requirements of the models in these fields.One more thing,this type of nonlinear model has no explicit solutions.For the sake of comparison its computation will be done by using different computational techniques.Regrettably,the aforementioned structural properties have not been restored in the existing computational techniques in literature.Therefore,the construction of structural preserving computational techniques are needed.The nonlinearmodel for cervical cancer is constructed by parametric perturbation technique.Well-known computer methods are considered for the computation of cervical cancer dynamics.The well-known existing methods in literature are Euler Maruyama,Euler and Runge Kutta.Nonstandard finite difference method or Implicitly driven explicit method is first time considered for aforesaid model under the assumptions given byMickens in a stochastic way.Unfortunately,the aforementioned existing methods did not reinstate structural properties of cervical cancer dynamics in the human population.Our plannedmethod is structural preserving and a powerful tool for all nonlinear models of biomedical engineering problems.We have verified that existing computational methods do not preserve dynamical properties.But,the implicitly driven explicit method is a good device for dynamical properties.In the support of assertions,convergence analysis of implicitly driven explicit method is presented. 展开更多
关键词 Cervical cancer model differential equations computer methods convergence analysis
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Al_(2)O_(3) andγAl_(2)O_(3) Nanomaterials Based Nanofluid Models with Surface Diffusion:Applications for Thermal Performance in Multiple Engineering Systems and Industries 被引量:2
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作者 Adnan Umar khan +4 位作者 Naveed Ahmed Syed Tauseef Mohyud-Din ilyas khan Dumitru Baleanu Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2021年第2期1563-1576,共14页
Thermal transport investigation in colloidal suspensions is taking a significant research direction.The applications of these fluids are found in various industries,engineering,aerodynamics,mechanical engineering and ... Thermal transport investigation in colloidal suspensions is taking a significant research direction.The applications of these fluids are found in various industries,engineering,aerodynamics,mechanical engineering and medical sciences etc.A huge amount of thermal transport is essential in the operation of various industrial production processes.It is a fact that conventional liquids have lower thermal transport characteristics as compared to colloidal suspensions.The colloidal suspensions have high thermal performance due to the thermophysical attributes of the nanoparticles and the host liquid.Therefore,researchers focused on the analysis of the heat transport in nanofluids under diverse circumstances.As such,the colloidal analysis of H_(2)O composed byγAl_(2)O_(3)and Al_(2)O_(3)is conducted over an elastic cylinder.The governing flow models ofγAl_(2)O_(3)/H_(2)O and Al_(2)O_(3)/H_(2)O is reduced in the dimensionless form by adopting the described similarity transforms.The colloidal models are handled by implementing the suitable numerical technique and provided the results for the velocity,temperature and local thermal performance rate against the multiple flow parameters.From the presented results,it is shown that the velocity of Al_(2)O_(3)–H_(2)O increases promptly against a high Reynolds number and it decreases for high-volume fraction.The significant contribution of the volumetric fraction is examined for thermal enhancement of nanofluids.The temperature of Al_(2)O_(3)–H_(2)O andγAl_(2)O_(3)–H_(2)O significantly increases against a higherϕ.Most importantly,the analysis shows thatγAl_(2)O_(3)–H_(2)O has a high local thermal performance rate compared to Al_(2)O_(3)–H_(2)O.Therefore,it is concluded thatγAl_(2)O_(3)–H_(2)O is a better heat transfer fluid and is suitable for industrial and technological uses. 展开更多
关键词 Thermal performance Al_(2)O_(3)andγAl_(2)O_(3)nanomaterials thermophysical attributes of nanomaterials stretching cylinder suction/blowing numerical scheme nusselt number
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Analysis and Dynamics of Fractional Order Mathematical Model of COVID-19in Nigeria Using Atangana-Baleanu Operator 被引量:2
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作者 Olumuyiwa J.Peter Amjad S.Shaikh +4 位作者 Mohammed O.Ibrahim Kottakkaran Sooppy Nisar Dumitru Baleanu ilyas khan Adesoye I.Abioye 《Computers, Materials & Continua》 SCIE EI 2021年第2期1823-1848,共26页
We propose a mathematical model of the coronavirus disease 2019(COVID-19)to investigate the transmission and control mechanism of the disease in the community of Nigeria.Using stability theory of differential equation... We propose a mathematical model of the coronavirus disease 2019(COVID-19)to investigate the transmission and control mechanism of the disease in the community of Nigeria.Using stability theory of differential equations,the qualitative behavior of model is studied.The pandemic indicator represented by basic reproductive number R0 is obtained from the largest eigenvalue of the next-generation matrix.Local as well as global asymptotic stability conditions for the disease-free and pandemic equilibrium are obtained which determines the conditions to stabilize the exponential spread of the disease.Further,we examined this model by using Atangana–Baleanu fractional derivative operator and existence criteria of solution for the operator is established.We consider the data of reported infection cases from April 1,2020,till April 30,2020,and parameterized the model.We have used one of the reliable and efficient method known as iterative Laplace transform to obtain numerical simulations.The impacts of various biological parameters on transmission dynamics of COVID-19 is examined.These results are based on different values of the fractional parameter and serve as a control parameter to identify the significant strategies for the control of the disease.In the end,the obtained results are demonstrated graphically to justify our theoretical findings. 展开更多
关键词 Mathematical model COVID-19 Atangana-Baleanu fractional operator existence of solutions stability analysis numerical simulation
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Heat Transfer in MHD Flow of Maxwell Fluid via Fractional Cattaneo-Friedrich Model:A Finite Difference Approach 被引量:2
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作者 Muhammad Saqib Hanifa Hanif +3 位作者 T.Abdeljawad ilyas khan Sharidan Shafie Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2020年第12期1959-1973,共15页
The idea of fractional derivatives is applied to several problems of viscoelastic fluid.However,most of these problems(fluid problems),were studied analytically using different integral transform techniques,as most of... The idea of fractional derivatives is applied to several problems of viscoelastic fluid.However,most of these problems(fluid problems),were studied analytically using different integral transform techniques,as most of these problems are linear.The idea of the above fractional derivatives is rarely applied to fluid problems governed by nonlinear partial differential equations.Most importantly,in the nonlinear problems,either the fractional models are developed by artificial replacement of the classical derivatives with fractional derivatives or simple classical problems(without developing the fractional model even using artificial replacement)are solved.These problems were mostly solved for steady-state fluid problems.In the present article,studied unsteady nonlinear non-Newtonian fluid problem(Cattaneo-Friedrich Maxwell(CFM)model)and the fractional model are developed starting from the fractional constitutive equations to the fractional governing equations;in other words,the artificial replacement of the classical derivatives with fractional derivatives is not done,but in details,the fractional problem is modeled from the fractional constitutive equations.More exactly two-dimensional magnetic resistive flow in a porous medium of fractional Maxwell fluid(FMF)over an inclined plate with variable velocity and the temperature is studied.The Caputo time-fractional derivative model(CFM)is used in the governing equations.The proposed model is numerically solved via finite difference method(FDM)along with L1-scheme for discretization.The numerical results are presented in various figures.These results indicated that the fractional parameters significantly affect the temperature and velocity fields.It is noticed that the temperature field increased with an increase in the fractional parameter.Whereas,the effect of fractional parameters is opposite on the velocity field near the plate.However,this trend became like that of the temperature profile,away from the plate.Moreover,the velocity field retarded with strengthening in the magnetic parameter due to enhancement in Lorentz force.However,this effect reverses in the case of the temperature profile. 展开更多
关键词 Viscoelastic fluid Cattaneo-Friedrich Maxwell model variable heating magnetohydrodynamic(MHD) porous medium fractional derivatives
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Computational Analysis of the Effect of Nano Particle Material Motion on Mixed Convection Flow in the Presence of Heat Generation and Absorption 被引量:2
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作者 Muhammad Ashraf Amir Abbas +3 位作者 Saqib Zia Yu-Ming Chu ilyas khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2020年第11期1809-1823,共15页
The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow mo... The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow model.The formulation of the flow model is based on basic universal equations of conservation of momentum,energy and mass.The prescribed flow model is converted to non-dimensional form by using suitable scaling.The obtained transformed equations are solved numerically by using finite difference scheme.For the analysis of above said behavior the computed numerical data for fluid velocity,temperature profile,and mass concentration for several constraints that is mixed convection parameterλt,modified mixed convection parameterλc,Prandtl number Pr,heat generation/absorption parameterδ,Schmidt number Sc,thermophoresis parameter Nt,and thermophoretic coefficient k are sketched in graphical form.Numerical results for skin friction,heat transfer rate and the mass transfer rate are tabulated for various emerging physical parameters.It is reported that in enhancement in heat,generation boosts up the fluid temperature at some positions of the surface of the sphere.As heat absorption parameter is decreased temperature field increases at position X=π/4 on the other hand,no alteration at other considered circumferential positions is noticed. 展开更多
关键词 Nano material mixed convection finite difference method heat generation/absorption SPHERES
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Temporal Stability Analysis of Magnetized Hybrid Nanofluid Propagating through an Unsteady Shrinking Sheet: Partial Slip Conditions 被引量:1
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作者 Liaquat Ali Lund Zurni Omar +3 位作者 Sumera Dero Yuming Chu ilyas khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2021年第2期1963-1975,共13页
The unsteady magnetohydrodynamic(MHD)flow on a horizontal preamble surface with hybrid nanoparticles in the presence of the first order velocity and thermal slip conditions are investigated.Alumina(Al_(2)O_(3))and cop... The unsteady magnetohydrodynamic(MHD)flow on a horizontal preamble surface with hybrid nanoparticles in the presence of the first order velocity and thermal slip conditions are investigated.Alumina(Al_(2)O_(3))and copper(Cu)are considered as hybrid nanoparticles that have been dispersed in water in order to make hybrid nanofluid(Cu-Al_(2)O_(3)/water).The system of similarity equations is derived from the system of partial differential equations(PDEs)by using variables of similarity,and their solutions are gotten with shooting method in the Maple software.In certain ranges of unsteadiness and magnetic parameters,the presence of dual solutions can be found.Further,it is examined that layer separation is deferred due to the effect of the hybrid nanoparticles.Moreover,the capacity of the thermal enhancement of Cu-Al_(2)O_(3)/water hybrid nanofluid is higher as compared to Al_(2)O_(3)/water based nanofluid and enhancements inCu are caused to rise the fluid temperature in both solutions.In the last,solutions stability analyzes were also carried out and the first solution was found to be stable. 展开更多
关键词 Cu−Al_(2)O_(3)/H2O hybrid nanofluid magnetic field slip conditions dual solutions
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Second Law Analysis of Magneto Radiative GO-MoS_(2)/H_(2)O–(CH_(2)OH)_(2) Hybrid Nanofluid 被引量:1
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作者 Adnan Umar khan +4 位作者 Naveed Ahmed Syed Tauseef Mohyud-Din Dumitru Baleanu Kottakkaran Sooppy Nisar ilyas khan 《Computers, Materials & Continua》 SCIE EI 2021年第7期213-228,共16页
Entropy Generation Optimization(EGO)attained huge interest of scientists and researchers due to its numerous applications comprised in mechanical engineering,air conditioners,heat engines,thermal machines,heat exchang... Entropy Generation Optimization(EGO)attained huge interest of scientists and researchers due to its numerous applications comprised in mechanical engineering,air conditioners,heat engines,thermal machines,heat exchange,refrigerators,heat pumps and substance mixing etc.Therefore,the study of radiative hybrid nanofluid(GO-MoS_(2)/C_(2)H_(6)O_(2)–H_(2)O)and the conventional nanofluid(MoS_(2)/C_(2)H_(6)O_(2)–H_(2)O)is conducted in the presence of Lorentz forces.The flow configuration is modeled between the parallel rotating plates in which the lower plate is permeable.The models which govern the flow in rotating system are solved numerically over the domain of interest and furnished the results for the temperature,entropy generation and thermophysical characteristics of the hybrid as well as conventional nanofluids,respectively.It is examined that the thermal profile intensifies against stronger thermal radiations and magnetic field.The surface of the plate is heated due to the imposed thermal radiations and magnetic field which cause the increment in the temperature.It is also observed that the temperature declines against more rotating plates.Further,the entropy production increases for more dissipative effects and declines against more magnetized fluid.Thermal conductivities of the hybrid nanofluid enhances promptly in comparison with regular liquid therefore,under consideration hybrid nanofluid is reliable for the heat transfer.Moreover,dominating thermal transport is perceived for the hybrid nanofluid which showed that hybrid suspension GO-MoS_(2)/C_(2)H_(6)O_(2)–H_(2)O is better for industrial,engineering and technological uses. 展开更多
关键词 Heat transfer thermal radiation Entropy Generation GO-MoS_(2)hybrid nanoparticles thermophysical characteristics
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Dual Branches of MHD Three-Dimensional Rotating Flow of Hybrid Nanofluid on Nonlinear Shrinking Sheet 被引量:1
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作者 Liaquat Ali Lund Zurni Omar +1 位作者 ilyas khan El-Sayed MSherif 《Computers, Materials & Continua》 SCIE EI 2021年第1期127-139,共13页
In this study,magnetohydrodynamic(MHD)three-dimensional(3D)flow of alumina(Al2O3)and copper(Cu)nanoparticles of an electrically conducting incompressible fluid in a rotating frame has been investigated.The shrinking s... In this study,magnetohydrodynamic(MHD)three-dimensional(3D)flow of alumina(Al2O3)and copper(Cu)nanoparticles of an electrically conducting incompressible fluid in a rotating frame has been investigated.The shrinking surface generates the flow that also has been examined.The single-phase(i.e.,Tiwari and Das)model is implemented for the hybrid nanofluid transport phenomena.Results for alumina and copper nanomaterials in the water base fluid are achieved.Boundary layer approximations are used to reduce governing partial differential(PDEs)system into the system of the ordinary differential equations(ODEs).The three-stage Lobatto IIIa method in bvp4c solver is applied for solutions of the governing model.Graphical results have been shown to examine how velocity and temperature fields are influenced by various applied parameters.It has been found that there are two branches for certain values of the suction/injection parameter b:The rise in copper volumetric concentration improved the velocity of hybrid nanofluid in the upper branch.The heat transfer rate improved for the case of hybrid nanofluid as compared to the viscous fluid and simple nanofluid. 展开更多
关键词 Nonlinear surface viscous dissipation MHD Hybrid nanofluid two branches
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Numerical Analysis of Novel Coronavirus (2019-nCov) Pandemic Model with Advection 被引量:1
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作者 Shumaila Azam Nauman Ahmed +6 位作者 Ali Raza Muhammad Sajid Iqbal Muhammad Rafiq ilyas khan Kottakkaran Sooppy Nisar Muhammad Ozair Ahmad Zafar Iqbal 《Computers, Materials & Continua》 SCIE EI 2021年第6期2933-2953,共21页
Recently,the world is facing the terror of the novel corona-virus,termed as COVID-19.Various health institutes and researchers are continuously striving to control this pandemic.In this article,the SEIAR(susceptible,e... Recently,the world is facing the terror of the novel corona-virus,termed as COVID-19.Various health institutes and researchers are continuously striving to control this pandemic.In this article,the SEIAR(susceptible,exposed,infected,symptomatically infected,asymptomatically infected and recovered)infection model of COVID-19 with a constant rate of advection is studied for the disease propagation.A simple model of the disease is extended to an advection model by accommodating the advection process and some appropriate parameters in the system.The continuous model is transposed into a discrete numerical model by discretizing the domains,finitely.To analyze the disease dynamics,a structure preserving non-standard finite difference scheme is designed.Two steady states of the continuous system are described i.e.,virus free steady state and virus existing steady state.Graphical results show that both the steady states of the numerical design coincide with the fixed points of the continuous SEIAR model.Positivity of the state variables is ensured by applying the M-matrix theory.A result for the positivity property is established.For the proposed numerical design,two different types of the stability are investigated.Nonlinear stability and linear stability for the projected scheme is examined by applying some standard results.Von Neuman stability test is applied to ensure linear stability.The reproductive number is described and its pivotal role in stability analysis is also discussed.Consistency and convergence of the numerical model is also studied.Numerical graphs are presented via computer simulations to prove the worth and efficiency of the quarantine factor is explored graphically,which is helpful in controlling the disease dynamics.In the end,the conclusion of the study is also rendered. 展开更多
关键词 2019-nCov infectious model with advection reproductive number stability analysis numerical graphs
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Computational Analysis of the Oscillatory Mixed Convection Flow along a Horizontal Circular Cylinder in Thermally Stratified Medium 被引量:1
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作者 Zia Ullah Muhammad Ashraf +3 位作者 Saqib Zia Yuming Chu ilyas khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2020年第10期109-123,共15页
The present work emphasizes the significance of oscillatory mixed convection stratified fluid and heat transfer characteristics at different stations of non-conducting horizontally circular cylinder in the presence of... The present work emphasizes the significance of oscillatory mixed convection stratified fluid and heat transfer characteristics at different stations of non-conducting horizontally circular cylinder in the presence of thermally stratified medium.To remove the difficulties in illustrating the coupled PDE’s,the finite-difference scheme with efficient primitive-variable formulation is proposed to transform dimensionless equations.The numerical simulations of coupled non-dimensional equations are computed in terms velocity of fluid,temperature and magnetic field which are computed to examine the fluctuating components of skin friction,heat transfer and current density for various emerging parameters.The governing parameters namely,thermally stratification parameter𝑆𝑆𝑡𝑡,mixed-convection parameter𝜆𝜆,Prandtl number Pr,magnetic force parameter𝜉𝜉and magnetic-Prandtl number𝛾𝛾are displayed graphically at selected values for velocity and heat transfer mechanism.It is computed that heat transfer attains maximum amplitude and good variations in the presence of thermally stratified parameter at each position𝛼𝛼=𝜋𝜋6⁄,𝛼𝛼=𝜋𝜋3⁄and𝛼𝛼=𝜋𝜋around the surface of non-conducting horizontally cylinder.The velocity of fluid attains certain height at station𝛼𝛼=𝜋𝜋6⁄for higher value of stratification parameter.It is also found that the temperature gradient decreases with stratification parameter𝑆𝑆𝑡𝑡,but it increases after a certain distance𝑌𝑌from the cylinder.The novelty of the current work is that due to non-conducting phenomena the magnetic effects are strongly observed far from the surface but exact at the surface are zero for each position. 展开更多
关键词 Mixed-convection oscillatory stratified flow non-conducting cylinder thermal stratification heat transfer.
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Structure Preserving Algorithm for Fractional Order Mathematical Model of COVID-19 被引量:1
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作者 Zafar Iqbal Muhammad Aziz-ur Rehman +4 位作者 Nauman Ahmed Ali Raza Muhammad Rafiq ilyas khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2022年第5期2141-2157,共17页
In this article,a brief biological structure and some basic properties of COVID-19 are described.A classical integer order model is modified and converted into a fractional order model withξas order of the fractional... In this article,a brief biological structure and some basic properties of COVID-19 are described.A classical integer order model is modified and converted into a fractional order model withξas order of the fractional derivative.Moreover,a valued structure preserving the numerical design,coined as Grunwald–Letnikov non-standard finite difference scheme,is developed for the fractional COVID-19 model.Taking into account the importance of the positivity and boundedness of the state variables,some productive results have been proved to ensure these essential features.Stability of the model at a corona free and a corona existing equilibrium points is investigated on the basis of Eigen values.The Routh–Hurwitz criterion is applied for the local stability analysis.An appropriate example with fitted and estimated set of parametric values is presented for the simulations.Graphical solutions are displayed for the chosen values ofξ(fractional order of the derivatives).The role of quarantined policy is also determined gradually to highlight its significance and relevancy in controlling infectious diseases.In the end,outcomes of the study are presented. 展开更多
关键词 Coronavirus pandemic model deterministic ordinary differential equations numerical methods convergence analysis
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Is Social Distancing, and Quarantine Effective in Restricting COVID-19 Outbreak? Statistical Evidences from Wuhan, China 被引量:1
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作者 Salman A.Cheema Tanveer Kifayat +4 位作者 Abdu R.Rahman Umair khan A.Zaib ilyas khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2021年第2期1977-1985,共9页
The flow of novel coronavirus(COVID-19)has affected almost every aspect of human life around the globe.Being the emerging ground and early sufferer of the virus,Wuhan city-data remains a case of multifold significance... The flow of novel coronavirus(COVID-19)has affected almost every aspect of human life around the globe.Being the emerging ground and early sufferer of the virus,Wuhan city-data remains a case of multifold significance.Further,it is of notable importance to explore the impact of unique and unprecedented public health response of Chinese authorities—the extreme lockdown of the city.In this research,we investigate the statistical nature of the viral transmission concerning social distancing,extreme quarantine,and robust lockdown interventions.We observed highly convincing and statistically significant evidences in favor of quarantine and social distancing approaches.These findings might help countries,now facing,or likely to face the wave of the virus.We analyzed Wuhan-based data of“number of deaths”and“confirmed cases,”extracted from China CDC weekly database,dated from February 13,2020,to March 24,2020.To estimate the underlying group structure,the assembled data is further subdivided into three blocks,each consists of two weeks.Thus,the complete data set is studied in three phases,such as,phase 1(Ph 1)=February 13,2020,to February 26,2020;phase 2(Ph 2)=February 27,2020 to March 11,2020;and phase 3(Ph 3)=March 12,2020 to March 24,2020.We observed the overall median proportion of deaths in those six weeks remained 0.0127.This estimate is highly influenced by Ph1,when the early flaws of weak health response were still prevalent.Over the time,we witnessed a median decline of 92.12%in the death proportions.Moreover,a non-parametric version of the variability analysis of death data,estimated that the average rank of reported proportions in Ph 3 remained 7,which was 20.5 in Ph 2,and stayed 34.5 in the first phase.Similar patterns were observed,when studying the confirmed cases data.We estimated the overall median of the proportion of confirmed cases in Wuhan as 0.0041,which again,is highly inclined towards Ph 1 and Ph 2.We also witnessed minimum average rank proportions for Ph 3,such as 7,which was noticeably lower than Ph 2,21.71,and Ph 1, 32.29. Moreover, the varying degree of clustering indicates that the effectivenessof quarantine based policies is time-dependent. In general, the declinein coronavirus transmission in Wuhan significantly coincides with the lockdown. 展开更多
关键词 COVID-19 k-mean clustering statistical methods variability analysis
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