Bundit Unyong

• Doctor of Philosophy
• Associate.Professor.Dr. at School of Science. Walailak University

This study aimed to investigate the existence, uniqueness, and Ulam-Hyers stability of solutions in a nonlinear coupled system of Hilfer-Hadamard sequential fractional integrodifferential equations, which were further enhanced by nonlocal coupled Hadamard fractional integrodifferential multipoint boundary conditions. The desired conclusions were ob...

We investigate the criteria for both the existence and uniqueness of solutions within a nonlinear coupled system of Hilfer-Hadamard sequential fractional differential equations featuring varying orders. This system is complemented by nonlocal coupled Hadamard fractional integral boundary conditions. The desired outcomes are attained through the app...

The present investigation aims to establish the existence and uniqueness of solutions for a system containing sequential fractional differential equations. Furthermore, boundary conditions that include the Riemann–Liouville fractional integral are taken into consideration. The existence of unknown functions, fractional derivatives, and fractional i...

The goal of this paper is to find the best of two sixth-order methods, namely, RK-Huta and RK–Butcher methods for solving the fuzzy hybrid systems. We state a necessary definition and theorem in terms of consistency for convergence, and finally, we compare the obtained numerical results of two different methods with analytical solution using two di...

This article focuses on a class of fourth-order singularly perturbed convection diffusion equations (SPCDE) with integral boundary conditions (IBC). A numerical method based on a finite difference scheme using Shishkin mesh is presented. The proposed method is close to the first-order convergent. The discrete norm yields an error estimate and theor...

This article addresses the study of a photovoltaic system for type-2 interval fuzzy models via event-triggered control (ETC). Compared to similar works initiated in the references, the necessary part of modeling the ETC for the photovoltaic system (\({\mathscr {P}}{{\mathscr {V}}}\)) is to produce the maximum path which should be followed to guaran...

The purpose of this paper is to investigate the existence and uniqueness of solutions to the Caputo sequential fractional differential equations and inclusions with integral boundary conditions. When it comes to proving the existence of solutions, the Krasnoselskii's fixed point theorem is employed. Further, the Banach's contraction principle and t...

Two non-uniform meshes used as part of the finite difference method to resolve singularly perturbed mixed-delay differential equations are studied in this article. The second-order derivative is multiplied by a small parameter which gives rise to boundary layers at x=0 and x=3 and strong interior layers at x=1 and x=2 due to the delay terms. We pro...

In this paper, we introduce and investigate the existence and stability of a tripled system of sequential fractional differential equations (SFDEs) with multi-point and integral boundary conditions. The existence and uniqueness of the solutions are established by the principle of Banach’s contraction and the alternative of Leray–Schauder. The stabi...

The purpose of this article is to discuss the existence, uniqueness, and Ulam–Hyers stability of solutions to a coupled system of fractional differential equations with Erdélyi–Kober and Riemann–Liouville integral boundary conditions. The Banach fixed point theorem is used to prove the uniqueness of solutions, while the Leray–Schauder alternative i...

The discrete-time system has more complex and chaotic dynamical behaviors as compared to the continuous-time system. This paper extends a discrete Leslie–Gower predator-prey system with the Allee effect in the predator’s population, whose dynamics are analyzed and explored. We have determined the equilibrium points and studied their local stability...

Impact of non-uniform heat source/sink and elastic deformation on entropy generation analysis for Cu − Fe3O4/ethylene glycol hybrid nanofluid flow past a stretching sheet with an inclined magnetic field, partial slip, and thermal radiations are investigated. Appropriate conversions are utilized for PDE's into ODE's. The dimensionless form is then a...

This article examines the issue of event-triggered L2-L∞ filtering for network-based neutral systems via Takagi-Sugeno (T-S) fuzzy approach. A dynamic discrete event-triggered scheme (ETS) is introduced to save the limited communication resource. Based on the T-S fuzzy model, the consider neutral type system with networked induced delays are repres...

An m-Ł℘,℘−1,…,1 labeling of a simple graph G is a mapping τ from the vertex set ∨G to 0,1,…,m such that τu−τv≥℘+1−du,v, ∀u,v∈∨G, where length of the shortest route connecting u and v is represented by du,v. The smallest m for which there exists a m-Ł℘,℘−1,…,1 labeling of G is known as the Ł℘,℘−1,…,1 labeling number of G, and it is described by λ℘G....

In this article, we investigate new results of existence and uniqueness for systems of nonlinear coupled differential equations and inclusions involving Caputo-type sequential derivatives of fractional order and along with new kinds of coupled discrete (multi-points) and fractional integral (Riemann-Liouville) boundary conditions. Our investigation...

In this article, we discuss the dynamics of a Leslie–Gower ratio-dependent predator–prey model incorporating fear in the prey population. Moreover, the Allee effect in the predator growth is added into account from both biological and mathematical points of view. We explore the influence of the Allee and fear effect on the existence of all positive...

This work investigates the finite-time event-triggered approach for recurrent neural networks with leakage term and its application. Here, decentralized event-triggered framework is recommended where event is checked at every sensor node related to local information for available triggering and the updated control is done whenever a centralized eve...

In this paper, we analyze the global asymptotic stability and global exponential stability with respect to the Clifford-valued neutral-type neural network (NN) models with time delays. By considering the neutral term, a Clifford-valued NN model with time delays is formulated, which encompasses real-valued, complex-valued, and quaternion-valued NN m...

This study is concerned about the stabilization for delayed fuzzy neutral-type system (DFNTS) with uncertain parameters under intermittent control. Firstly, by constructing the augmented Lyapunov-Krasovskii functional (LKF) about different time delays along with single and double auxillary function-based integral inequalities (SAFBII, and DAFBII, r...

This research mainly focuses on the effects of heat absorption/generation and radiation on the hydromagnetic flow of Fe3O4-ethylene glycol nanofluid through a shrinking wall with porous medium and the computation of the entropy generation. We considered basic governing ordinary differential equations into partial differential equations by using app...

A study on the parametric form of fuzzy numbers is presented in this paper. The Runge-Kutta Fehlberg method is exploited to yield the approximate solution with respect to the second type of fuzzy Fredholm integro-differential equations. Both linear and nonlinear numerical examples are provided in our analysis. The results ascertain the effectivenes...

In this paper, we study the Hyers-Ulam stability with respect to the linear differential condition of fourth order. Specifically, we treat ${\psi}$ as an interact arrangement of the differential condition, i.e., where ${\psi} \in c^4 [{\ell}, {\mu}], {\Psi} \in [{\ell}, {\mu}]$. We demonstrate that ${\psi}^{iv} ({\varkappa}) + {\xi}_1 {\psi}{'''}...

In the current study, we conduct an investigation into the Hyers–Ulam stability of linear fractional differential equation using the Riemann–Liouville derivatives based on fractional Fourier transform. In addition, some new results on stability conditions with respect to delay differential equation of fractional order are obtained. We establish the...

This paper deals with the global asymptotic robust stability (GARS) of neural networks (NNs) with constant time delay via Frobenius norm. The Frobenius norm result has been utilized to find a new sufficient condition for the existence, uniqueness, and GARS of equilibrium point of the NNs. Some suitable Lyapunov functional and the slope bounded func...

The aim of this paper is to prove some new type of Hermite-Hadamard, Hermite-HadamardFejer, Dragomir-Agarwal inequalities for Fourier integral transform. These results pave the way to the researcher in obtaining complete unique functional inequalities for a well established inequalities in use and that involves convex functions.

we focus on the global stability analysis with respect to dynamical delayed neural networks (NNs) that contain parameter uncertainties.

In this paper, we focus on the global stability analysis with respect to dynamical delayed neural network (NN) models that contain parameter uncertainties. Many investigations on the sufficient conditions utilizing different upper bounds for the norm of interconnection matrices pertaining to the global asymptotic robust stability of delayed NN mode...

In this work a modified SEIR-SVEVIV model that described the dynamics transmission of malaria disease was proposed and analyzed. The standard method is used to analyze the behaviors of the proposed model. The results shown that there were two equilibrium points; disease free and endemic equilibrium point. The qualitative results are depended on a b...

In this work, a modified SEIR model for the transmission of dengue fever was proposed and analyzed. We use the efficiency of education campaign u as the control measures to reduce the contact between susceptible human and infected mosquito, the role of education to inform people that they should use mosquito repellent to protect yourself from mosqu...

Background: Optimal control theory is applied to a modified SITR model, we use two controls function representing education campaign and a therapeutic treatment that to reduce the number of the infectious individuals, and to increase the number of susceptible individuals and treatment individuals, respectively. The objective function is based on a...

Background: In this work the dynamics of transmission of denque fever was proposed and analyzed. The standard method is used to analyze the behaviors of the proposed model. In the present investigation of dynamical transmission of denque fever, the effect of human vaccination and the cost of this strategy are taken into account. Results: There were...

A numerical algorithm, based on the Galerkin finite element method and the enthalpy formulation, is developed for solving the coupled turbulent fluid flow and heat transfer problem in a domain with a moving phase-change boundary. The governing equations consist of the continuity equation, the Navier–Stokes equations, the energy equation and the mod...