In this paper the periodic solutions of fourth order delay differential equation of the form $ddddot{x}(t)+adddot{x}(t)+f(ddot{x}(t-tau(t)))+g(dot{x}(t-tau(t)))+h({x}(t-tau(t)))=p(t)$  is investigated. Some new positive periodic criteria are given.  

There has been a growing interest in combining both neural network and fuzzy system, and as a result, neuro-fuzzy computing techniques have been evolved. ANFIS (adaptive network-based fuzzy inference system) model combined the neural network adaptive capabilities and the fuzzy logic qualitative approach. In this paper, a novel structure of unsupervised ANFIS is presented to solve differential e...

The study of the fuzzy differential equation is a topic that researchers are interested in these days. By modelling, this can be used to resolve issues real world. However, finding an analytical solution challenging. Thus, aims present fuzziness traditional Runge–Kutta Cash–Karp fourth-order method solve first-order equation. Later, referred as method. There two types equations solved: autonomo...

By using the method of successive approximation, we prove the existence and uniqueness of a solution of the fuzzy differential equation x′(t)= f(t,x(t)), x(t0)= x0. We also consider an -approximate solution of the above fuzzy differential equation.

Fuzzy differential equation models are suitable where uncertainty exists for real-world phenomena. Numerical techniques used to provide an approximate solution these in the absence of exact solution. However, existing studies that have developed numerical solving FIVPs possess absolute error accuracy could be improved. This is as a result low order and non-self-starting properties by previous s...

In this paper, solution of fuzzy differential equation under general differentiability is obtained by simulink. The simulink solution is equivalent or very close to the exact solution of the problem. Accuracy of the simulink solution to this problem is qualitatively better. An illustrative numerical example is presented for the proposed method. Keywords—Fuzzy differential equation, Generalized ...

In this paper, an improved predictor-corrector methods (IPC) to solve fuzzy differential equation under generalized differentiability are discussed. The methods proposed here are based on generalized characterization theorem. Using the Generalized Characterization we can translate a fuzzy differential equation into two ODE systems. Also, the convergence and stability of the proposed methods are...

Singular perturbation problems have been studied by many mathematicians. Since the approximate solutions of these problems are as the sum of internal solution (boundary layer area) and external ones, the formation or non-formation of boundary layers should be specified. This paper, investigates this issue for a singular perturbation problem including a first order differential equation with gen...