A systematic perturbation procedure is employed to derive ordered periodic and quasi-periodic solutions and their stability conditions associated with a general nonlinear autonomous system in the vicinity of a compound critical point. The critical point is characterized by two distinct pairs of pure imaginary eigenvalues of the Jacobian. The method, which is based on a Unified Intrinsic Harmoni...

We consider the real stationary two-dimensional Schrödinger equation. With the aid of any its particular solution we construct a Vekua equation possessing the following special property. The real parts of its solutions are solutions of the original Schrödinger equation and the imaginary parts are solutions of an associated Schrödinger equation with a potential having the form of a potential obt...

The objective of this study is to find the temperature distribution of a slab as it moves through the pusher-type preheat furnaces. First, the imaginary planes method (IPM) as a new and applicable method for calculation of radiation heat transfer in industrial furnaces is studied, and the two-dimensional form of this method is used to calculate heat flux and temperature distribution in the furn...

Since the Sassanid era, many reliefs and seals have left and by reviewing their designs, the mythical and religious attitudes of those people can be understood. The purpose of this article is to decode and interpret the symbolic paintings and to review and study the myths, concepts, and religious rituals of this period. The question is that what the divine and human origin of the symbolic paint...