SERIES SOLUTION OF TYPHOID FEVER MODEL USING DIFFERENTIAL TRANSFORM METHOD

In this paper, a reliable algorithm based on an adaptation of the standard differential transform method is presented, which is the multi-step differential transform method (MSDTM). The solutions of non-linear oscillators were obtained by MSDTM. Figurative comparisons between the MSDTM and the classical fourth-order Runge-Kutta method (RK4) reveal that the proposed technique is a promising tool to solve non-linear oscillators.

A numeric–analytic method for approximating the chaotic Chen system

In this paper the Modified Equations of Emden type (MEE), χ+αχχ+βχ 3 is solved numerically by the differential transform method. This technique doesn’t require any discretization, linearization or small perturbations and therefore it reduces significantly the numerical computation. The current results of this paper are in excellent agreement with those provided by Chandrasekar et al. [1] and thereby illustrate the reliability and the performance of the differential transform method. We have also compared the results with the classical Runge-Kutta 4 (RK4) Method.

A multi-step differential transform method and application to non-chaotic or chaotic systems

In recent years, there has been a tendency towards renewable energy sources considering the damages caused by non-renewable energy resources to nature and humans. One of the renewable energy sources is wind and energy is obtained with the help of wind turbines. To determine the behavior of wind turbines under earthquake loads, dynamic characteristics are required. In this study, the differential transformation method is proposed to determine the free vibration analysis of wind turbines with a variable cross-section. The wind turbine is modeled as an equivalent variable continuous flexural beam and blade weight is considered as a point mass at the top of the structures. The differential equation representing the free vibration of the wind turbine is transformed into an algebraic equation with the help of differential transformation method and the angular frequencies and the mode shapes of the wind turbine are obtained by the help of the differential transformation method. In the study, a sample taken from the literature was solved with the presented method and the suitability of the method was investigated. The same wind turbine example also modeled by finite element modelling software, ABAQUS. Results of the finite element model and differential transformation method are compared with each other and the results are in good agreement.

This paper employs differential transformation method (DTM) to study the dynamic behavior of a gyroscope control system. The analytical results reveal a complex dynamic behavior comprising periodic, sub-harmonic, quasi-periodic, and chaotic responses of the center of gravity. Furthermore, the results reveal the changes which take place in the dynamic behavior of the gyroscope control system as the external force is increased. The current analytical results by DTM are found to be in good agreement with those of Runge-Kutta method (RKM). Therefore, the proposed method provides an effective means of gaining insights into the nonlinear dynamics of gyroscope systems.

Heat transfer analysis for the Falkner–Skan wedge flow by the differential transformation method

Predator-prey models are the building blocks of the ecosystems as biomasses are grown out of their resource masses. Different relationships exist between these models as different interacting species compete, metamorphosis occurs and migrate strategically aiming for resources to sustain their struggle to exist. To numerically investigate these assumptions, ordinary differential equations are formulated, and a variety of methods are used to obtain and compare approximate solutions against exact solutions, although most numerical methods often require heavy computations that are time-consuming. In this paper, the traditional differential transform (DTM) method is implemented to obtain a numerical approximate solution to prey-predator models. The solution obtained with DTM is convergent locally within a small domain. The multi-step differential transform method (MSDTM) is a technique that improves DTM in the sense that it increases its interval of convergence of the series expansion. One predator-one prey and two-predator-one prey models are considered with a quadratic term which signifies other food sources for its feeding. The result obtained numerically and graphically shows point DTM diverges. The advantage of the new algorithm is that the obtained series solution converges for wide time regions and the solutions obtained from DTM and MSDTM are compared with solutions obtained using the classical Runge-Kutta method of order four. The results demonstrated is that MSDTM computes fast, is reliable and gives good results compared to the solutions obtained using the classical Runge-Kutta method.

This paper is devoted to introduce a numerical simulation using the differential transformation method (DTM) with a theoretical study for the effect of viscous dissipation on the steady flow with heat transfer of Newtonian fluid towards a permeable stretching surface embedded in a porous medium with a second order slip. The governing nonlinear partial differential equations are converted into a system of nonlinear ordinary differential equations (ODEs) by using similarity variables. The resulting ODEs are successfully solved numerically with the help of DTM. Graphic results are shown for nondimensional velocities and temperatures. The effects of the porous parameter, the suction (injection) parameter, Eckert number, first and second order velocity slip parameters and the Prandtl number on the flow and temperature profiles are given. Moreover, the local skin-friction and Nusselt numbers are presented. Comparison of numerical results is made with the earlier published results under limiting cases.

SOLUTION OF HIGHER-ORDER ABEL EQUATIONS BY DIFFERENTIAL TRANSFORM METHOD

The mathematical model for dengue fever transmission studied by [1], has been re-investigated. The differential transformation method (DTM) is used to compute the semi-analytical solutions of the non-linear differential equations of the compartment (SIR) model of dengue fever. This epidemiology problem is well-posed. The effect of treatment as a control measure is studied through the growth equations of exposed and infected humans. The inadvertent errors in the recurrence relations (DTM) of equations for dengue disease transmission including initial conditions have been removed. Furthermore, the semi-analytic solutions of the model are obtained and verified with the built-in function AsymptoticDSolveValue of Wolfram Mathematica. It has been found that results obtained from the DTM are valid only for small-time t (t < 1.5), as t becomes large, the human population (exposed and recovered) and infected vector population become negative.

Simulation of settling velocity and motion of particles in drilling operation

Solution of free vibration equation of elastically supported Timoshenko columns with a tip mass by differential transform method

Skin cancer is one of the most common cancers, and is primarily caused by long-term exposure to ultraviolet (UV) radiation. Understanding these dynamics is critical for the development of effective preventive and treatment measures. In this study, we examined a mathematical model of skin cancer induced by UV rays, categorizing the total population into four compartments: susceptible [Formula: see text], infected [Formula: see text], recovered [Formula: see text], and UV radiation [Formula: see text]. To solve the system of nonlinear differential equations and obtain a numerical solution for the SIRU model, we employed three semi-analytical methods: the differential transform method (DTM), Shehu transformation–Akbari–Ganjis–Pade approximation method (SAGPM), and higher-order inverse polynomial method (HOIPM). Each method was effective in providing highly accurate solutions with minimal computational effort. Compared to the [Formula: see text] solver, these semi-analytical methods have been validated for their accuracy, confirming their reliability and efficiency in solving complex real-world problems, leading to interesting findings. This study also investigated the impact of key parameters, offering valuable insights into the response and behavior of the skin cancer model under various conditions. These findings enhance our understanding of the dynamics of skin cancer.

In this work, the multi-step differential transformation method (MSDTM) is applied to approximate a solution of the hyperchaotic Rossler system. MSDTM is adapted from the differential transformation method (DTM). In this method, DTM is implemented in each subinterval. Results are compared with a fourth-order Runge Kutta method and a standard DTM. The results show that the MSDTM is an efficient and powerful technique for solving hyperchaotic Rossler systems and this method is more accurate than DTM.