The reliability and efficiency of free space optics (FSO) systems is significantly degraded by attenuation caused by different climate conditions and atmospheric turbulence. In this work, an FSO transmission system with high-speed transmission capability is proposed by deploying orthogonal frequency division multiplexing (OFDM) to mitigate channel fading effects. Further, we propose the hybridization

The physics of the (4 + 1)-dimensional Fokas equation follows necessarily from the physical nature of the Kadomtsev–Petviashvili and Davey-Stewartson equations in wave theory. In this article, we consider the nonlinear (4+1)-dimensional Fokas partial differential equation. Two recognizable methods namely improved F-expansion and generalized exp(-ϕ(ξ))-expansion methods are proposed to investigate the

This article mainly emphases on the study of magneto Cu-Al2O3/water hybrid nanofluid flow in a non-Darcy porous square cavity. The square geometry is a lid-driven enclosure with an inside heated square obstacle. Cattaneo-Christov heat flux pattern is used for the formulation of the heat equation. This type of problems may be applicable in the high temperatures in the different scientific processes

The present work investigates the single and overtaking collision of multi-shock wave excitations having space fractional evolution in a thin viscoelastic tube filled with incompressible inviscid fluid. The previously proposed model equations are considered to study such physical scenarios. The spatial fractional Burgers equation is formulated by implementing the reductive perturbation method form

The isothermal sorption experiments of CH4, CO2 and CH4/CO2 mixture gases on shale were performed. The sorption affinities of CH4, CO2 and CH4/CO2 mixture gases were compared using Henry’s coefficient (KH). The thermodynamics of sorption of CH4, CO2 and their mixture were discussed based on surface potential (Ω), entropy loss (ΔS) and change of Gibbs free energy (ΔG). It is shown that the uptakes of

This research was undertaken to optimize the Se(IV) adsorption from aqueous solutions by Cyperus laevigatus biomass and green-synthesized nanosilver (AgNPs). A full 24 factorial experimental design was utilized to distinguish the effects of pH, initial metal concentration (Co), adsorbent dose concentration (C. laevigatus biomass, X1 & AgNPs, X2) and contact time (t). Response surface methodology (RSM)

In this paper, a new interference-tolerant fast convergence zeroing neural network (ITFCZNN) using a novel activation function (NAF) for solving dynamic matrix inversion (DMI) is presented and investigated. Compared with the original zeroing neural network (OZNN) models, the proposed ITFCZNN not only has the ability to converge to 0 within a fixed-time, but also resist different types of interference

Aiming at sports and daily training of athletes in rehabilitation therapy, a wearable sports posture measurement system is proposed in combination with the Internet of Things technology. By choosing a professional coach to wear the system, the experiment was verified with common sports postures, and the actual measured sports information was analysed and processed. The experimental results show that

After the analysis and forecast of COVID-19 spreading in China, Italy, and France the WHO has declared the COVID-19 a pandemic. There are around 100 research groups across the world trying to develop a vaccine for this coronavirus. Therefore, the quantitative and qualitative analysis of the COVID–19 pandemic is needed along with the effect of rapid test infection identification on controlling the spread

In this paper, a modified reproducing kernel algorithm is proposed to solve a class of quadratic and cubic logistic equations with Caputo-Fabrizio fractional derivative in Hilbert space. These equations are the generalization of Verhulst’s model which describes population growth taking in account that individuals will compete for limited resources. A novel reproducing kernel function is constructed

A mathematical model to estimate transmission dynamics of COVID-19 is developed. A real data of confirmed cases for Ethiopia is used for parameter estimation via model fitting. Results showed that, the diseases free and endemic equilibrium points are found to be locally and globally asymptotically stable for Ro<1 and Ro>1 respectively. The basic reproduction number is Ro=1.5085. Optimal control analysis

The environment and the physiological conditions play a vital role in the thermal processes in the human tissues, such as the multi-layered human-eye. In this work, a mathematical model of the human eye concerning the change in blood perfusion, porosity, evaporation rate, and ambient temperatures has been formulated based on non-Fourier heat conduction law with appropriate boundary and interface conditions

We apply a novel computation approach to determine the numerical solution of variable-order fractional optimal control problems. The dynamic constraint of these problems is considered with variable-order (VO) fractional derivatives. The numerical procedure is based on the Genocchi polynomials. To carry out the suggested technique, the Genocchi operational matrix of the VO fractional integral is calculated

The Al-Najaf sea is a natural groundwater depending depression reservoir. The increase in uncontrolled dumping of solid waste in nearby areas and the use of sewage and animal manure as agricultural enhancing agents raise the fear of threatening the natural life in this lake by increasing metal concentrations in sediments. Forty-eight samples of sediments were collected, and the concentrations of eight

The Doubly Fed Induction Generator based Wind Turbine (WT-DFIG) suffers from instability while steady-state operation if improperly controlled. This paper proposes and evaluates three Scalar strategies that ensure Maximum Power Point Tracking (MPPT) and stabilize the WT-DFIG. Both of the generator electromagnetic torque – speed and the wind turbine mechanical torque-speed characteristics are taken

This paper concerns the modelling of the simulation structure for the torsional stiffness evaluation of a Formula SAE vehicle frame and presents some insights into the modelling of the problem using a beam-like model together with geometrical simplifications. The insights consist of presenting utilized simplifications and assessing their influence on torsional stiffness. The simulation model, consisting

In batch production planning, managers must consider the unforeseeable circumstances in the fabrication process and resources available to meet demand on time and determine the optimal replenishment policy. To address these concerns, this study examines a hybrid fabrication system incorporating outsourcing, stochastic machine failures, and random scraps. The objective is to decide the optimal uptime

With the continuous development of economic strength and science and technology, the construction of Intelligent Transportation System(ITS) has become a new development direction in many cities. A complete and accurate traffic dataset can improve the accuracy of traffic prediction and promote the construction of ITS in cities. Most of the existing traffic datasets are collected on highways, and they

In the Industrial Internet of Things (IIoT), peer-to-peer (P2P) distributed energy (DE) transactions exist in various scenarios. This paper attempts to improve the intelligence, real-timeliness, and security of the direct transaction between DE generation companies (DEGCs) and users, and reduce the default frequency of distributed power (DP) transactions. For these purposes, a P2P DE transaction model

The current research is conducted to investigate the slip effect and to analyze entropy production in both hybrid nanofluids, and common nanofluids flow past a convectively heated three-dimensional stretching sheet placed in a porous medium. The slip flow is considered in a Darcy-Forchheimer’s scheme by incorporating the nonlinear thermal radiation. Water is taken as base fluid, while Copper and Titanium

Concrete mortar segregation during vertical pipeline gravity transportation will form a weak part in the shaft lining, which poses a challenge for deep mine shaft safety. The specific gravity difference between aggregate and slurry will cause relative motion; the relative velocity is detrimental to the mortar workability, which plays a significant role in mortar segregation. A prediction model of the

This study investigated the removal of phenol, Chemical Oxygen Demand (COD), and ammonia from pharmaceutical wastewater using activated sludge (AS) and extended aeration (EA) systems. Also, the impact of adding activated carbon media on the performance of the two systems has been studied. Synthetic sewage was used with a composition of COD equaling 1500 mg/L. The experimental work was divided into

A new design of soil erosion and rainfall simulator is presented at this study as an attempt to deduce a mathematical formula of soil surface erosion phenomenon to describe the behavior of the sandy soil under the rainfall simulation, soil deformation such gullies and surface eroding rills are monitored by the Digital Close Range Photogrammetry (DCRP) technique that includes capturing digital images

Mathematical tools called differential and integral operators are used to model real world problems in all fields of science as they are able to replicate some behaviors observed in real world like fading memory, long-range dependency, power law, random walk and many others. Very recently the world has faced a serious challenge since the breakout of corona-virus started in Wuhan, China. The deathly

In this manuscript, a qualitative analysis of the mathematical model of novel coronavirus (COVID-19) involving anew devised fractal-fractional operator in the Caputo sense having the fractional-order q and the fractal dimension p is considered. The concerned model is composed of eight compartments: susceptible, exposed, infected, super-spreaders, asymptomatic, hospitalized, recovery and fatality. Under

In this research work, a non-linear dynamical modified SEIR model of the recent pandemic, due to Coronavirus-19 disease (COVID-19) for different countries like Malaysia and Pakistan, is considered under nonsingular fractional order derivative. For this model, some qualitative results, existence theory, and numerical solution are studied by using fixed point approach and fractional Adams-Bashforth method

Systems of high-dimensional nonlinear ordinary differential equations play a significant role in Physics and applied sciences including big-data optimization, financial models, epidemic disease models. In this paper, we are concerned with numerical solutions of Bao’s system that is a 4-dimensional hyperchaotic system introduced by Bo-Cheng and Zhong (2008). We solve the Bao’s system with both the Crank-Nicolson

Power communication network is an indispensable unit to maintain power network operation. The application of optical fiber nanotechnology in power communication transmission is studied in this paper. The optical fiber nanotechnology is applied to the power communication network (optical transmission network technology is the main transmission technology), and the functional model of the optical transmission

This paper analyzes the network architecture of the Iridium system, Orbcomm system, Narrow Band-Internet of Things (NB-IoT) and Long Range Radio (Lo Ra) in the satellite 5G mobile communication system. A new Dynamic Routing based on Multi-factor Forwarding (MF-DR) protocol is proposed. This paper simulates the ladder-type data fusion algorithm in terms of energy consumption in the Wireless Sensor Network

In the current research, optimal locations on aircraft panels are thickened to delay the flutter occurrence. A standard square isotropic Aluminum panel of 12 × 12 in. is considered. In formulating the model, the Kirchhoff-Love hypothesis and the Von-Karman nonlinear strain-displacement relations are applied. The quasi-steady first-order piston aerodynamic theory is used to calculate the applied load

This study presented a novel shape photonic crystal fiber based gas sensor for the first time. Perfectly circular shape air hole are arranged to form core and cladding region. Based on full vector finite element method (FV-FEM) and circular shape perfectly matched layer (PML) the designed sensor has been investigated. The model field, effective mode index, sensitivity, confinement loss, effective mode

In this paper, deep learning is employed to propose an Artificial Neural Network (ANN) based online incremental learning technique for developing an adaptive and non-intrusive analytical model of Covid-19 pandemic to analyze the temporal dynamics of the disease spread. The model is able to intelligently adapt to new ground realities in real-time eliminating the need to retrain the model from scratch

COVID-19, an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), starting from Wuhan city of China, plagued the world in the later part of 2019. We developed a deterministic model to study the transmission dynamics of the disease with two categories of the Susceptibles (ie immigrant Susceptibles and local Susceptible). The model is shown to have a globally stable

The aim of this study is to suggest a reliable low cost smart system for automating the heat treatment process. This system will reduce human direct interaction. The Fuzzy-PI control algorithm combined with ON/OFF algorithm was designed to automate the whole system operations. The overall automated furnace system includes control unit, algorithm, sensor and drive circuit was simulated in MATLAB/Simulink

In this paper, we applied the Sobol’s method on an already existing mathematical model of coronavirus disease 2019 (covid-19). The objectives of this research work are to study the individual effects of involved parameters as well as combine (mutual) effects of parameters on output variables of covid-19 model. The study is also useful to identify the ranking of key model parameters and factors fixing

In this paper, we proposed and investigated a discretized form of a fractional-order multi-drug antimicrobial resistance model. The existence and the uniqueness of the proposed model is studied. The impacts of varying the parameters of the system are examined. Under certain conditions, the system undergoes some kinds of bifurcations. It is established that the fractional-order parameter affects the

In this article, optimal control for variable order fractional multi-delay mathematical model for the co-infection of HIV/AIDS and malaria is presented. This model consists of twelve differential equations, where the variable order derivative are in the sense of Caputo. Three control variables are presented in this model to minimize the number of the co-infected individuals showing no symptoms of AIDS

This paper is about the implementation of the pseudo-spectral method based on the Lagrange polynomials to the numerical study of the multi-term time-fractional differential equations. Also, a semi-discrete approximation scheme used to the conversion of this equation to a system of ordinary fractional differential equations. To maintain the high accuracy of the spectral method, we applied the Mittag-Leffler

In this paper, a generalized (3 + 1)-dimensional nonlinear evolution equation (NLEE) is proposed and examined. This investigated NLEE is undoubtedly a robust mathematical model in real-world applications. Because several essential and commonly used relative differential equations can be obtained by considering some specific choices in the given general form. In this way, many new solitary wave solutions

In this paper, on the basis of the reproducing kernel functions, a novel meshless algorithm is explored for fractional advection–diffusion-reaction equations (ADREs) with Caputo time variable order. Firstly, the Gaussian kernel function and the Mittag–Leffler kernel function are introduced and combined to construct a new binary reproducing kernel function. Secondly, base on the constructed reproducing

In this paper, we propose a new SEIRS model and are concerned with stability and numerical solutions of the model. The model is generated under certain assumptions such as individuals are vaccinated or have a special treatment but do not carry lifelong immunity. After generating a new SEIRS model, we perturb the model into fractional time derivative form where Caputo type fractional-order derivative

This paper constructs approximate solutions of the epidemic system of HIV/AIDS transmission model with the help of the conformable fractional differential transform method. The fractional derivatives considered in this paper are described in the sense of the conformable operator. This method provides the approximate solutions speedily in the form of a convergent series. The results show the efficiency

The manuscript details a numerical method for solving a system of fractional differential equations (SFDEs) based on the Caputo fractional derivative by the Ritz method. To use this method, we transform the SFDEs into an optimization problem and obtain the system of nonlinear algebraic equations. Using polynomials of basis functions, we approximate solutions and obtain the coefficients of polynomial

This article is devoted to study a compartmental mathematical model for the transmission dynamics of the novel Coronavirus-19 under Caputo fractional order derivative. By using fixed point theory of Schauder’s and Banach we establish some necessary conditions for existence of at least one solution to model under investigation and its uniqueness. After the existence a general numerical algorithm based

Y. Xu (2016) investigated existence results of Caputo fractional differential equations with integral and anti-periodic boundary conditions of fractional order α∈(1,2). In this paper, we investigate the existence of solutions for fractional differential equation with integral and anti-periodic boundary conditions due to Y. Xu for infinite systems in the multivalued case (inclusions). Our results are

This paper presents analytical solutions of a time-space-fractional Black-Scholes model (TSFBSM) using a coupled technique referred to as Fractional Complex Transform (FCT) with the aid of a modified differential transform method. The nature of the derivatives is in the sense of Jumarie. The considered cases and applications show more consistency of the TSFBSM with an actual integer and fractional

The time-domain approximation of the Grünwald–Letnikov fractional derivative is intuitive and widely adopted in the design of fractional-order proportional-integral (FOPI) controllers. To solve the accuracy reduction caused by truncating the series, an optimized discrete FOPI is presented. The effectiveness of the new FOPI is highlighted and compared with the one exhibited by a controller implemented

As an important electronic device, filter is applied to all kinds of electronic products. In this paper, a new ℘-order R-L High-pass filter (HPF) modeled by the local fractional derivative (LFD) is proposed for the first time. With the help of the local fractional Laplace transform (LFLT), we obtain the non-differentiable(ND) transfer function, and present the expressions of ND amplitude-frequency

An SIR-type (Susceptible-Infected-Recovered) model for the study of the spread of Ebola Virus Disease (EVD) is developed, by using conformable derivatives. Every possible way of transmission of the disease is incorporated (direct or indirect), such as funeral practices, consumption of contaminated bush meat and the environmental contamination etc. We have added an extremely important term to the model

This paper investigates the role of fractional calculus in data fitting. We show that while the Caputo and Atangana-Baleanu fractional derivatives can be applied successfully in data fitting, this might not be true for the conformable derivative. The conformable derivative results in an unnecessarily complicated differential equation that warrants the use of numerical methods, thus compromises the

We construct the two unique piecewise C3-splines of degree six and eight to approximate the solution of fractional integro-differential equations. Existence and uniqueness of the solution of second order fractional integro-differential equation has been proved. Convergence analysis of the presented methods have been discussed. Illustrative examples are included to demonstrate the validity and applicability

This work presents a numerical and experimental investigation of sawdust gasification in a fluidized bed using air. The fluidized bed reactor was tested in the Faculty of Engineering, Mansoura University, Egypt. In the experimental part, the experiments were made in a fluidized bed gasifier to optimize the gasifying of sawdust pellets using air. The syngas composed mainly of CO, H2, CH4, and CO2 as

This research article elaborates the salient attributes of sundry variables i.e., Darcy-Forchheimer number, mixed convection parameter, porosity parameter, Weissenberg number, slip parameter, Prandtl number, activation energy parameter and chemical reaction parameter on the forced convective Darcy-forchheimer flow of non-Newtonian fluid (Carreau-Yasuda fluid) subject to stretchable and flat surface

Given the complexity of the wind environment around bridge–tunnel sections in canyons, flow fields are complex and changeable, resulting in transient aerodynamic loads on vehicles. Consequently, vehicles tend to sideslip or drift off lanes, affecting handling stability. An aerodynamic model coupled with a two-degrees-of-freedom dynamic model is proposed to reveal the aerodynamic performance and dynamic

The characteristics of Stefan blowing effects in a magneto-hydrodynamic flow of a Casson fluid past a stretching sheet are investigated. The effects of radiation, heat source/sink, Newtonian heating, Arrhenius activation energy and binary chemical reaction are considered for heat and mass transfer analysis. The homotopy analysis method (HAM) was utilised to solve the transformed non-dimensionalized

A significant characteristic of the strata in the Yimeng Mountain area is the dual earth-rock structure. Soil thickness directly affects the habitat conditions and is closely related to the survival rate of vegetation. This study aims to reveal the spatial distribution characteristics and influencing factors of the soil thickness in a typical watershed in the Yimeng mountain area. In April 2019, 1816

Covid19 an ecumenical pandemic perpetuates to take lakhs of lives and consistently taking its shape as major threat. Skeptically and turmoil in divergent perspectives perpetuate to grow. The most prominent contributing factor to all this is the lack of methodologies to test Covid samples at a more immensely colossal scale. Highly scalable, cost efficacious and flexible diagnosis methodology can contribute

The motivation of this paper is to construct the solution of fractional partial differential equations (FPDEs) by the combination of Laplace transform homotopy analysis method (LHAM) and the Laplace transform residual power series method (LRPSM) with weighted Atangana-Baleanu and weighted Caputo-Fabrizio fractional derivatives with specific weighted functions. Moreover, the solutions are analyzed by