objective: this research aims at shedding light on well-being psychiatric aspects of resiliency and sense of humour between patients who suffer from coronary artery disease and healthy individuals. method: the methodology employed is ex-post facto and the study population includes two groups of patients and healthy individuals who live in rasht. the samples under investigation consist of two hu...

We prove that the Lorenz equations support a strange attractor, as conjectured by Ed-ward Lorenz in 1963. We also prove that the attractor is robust, i.e., it persists under small perturbations of the coeecients in the underlying diierential equations. The proof is based on a combination of normal form theory and rigorous numerical computations.

By applying the undetermined coefficient method, this paper finds homoclinic and heteroclinic orbits in the Chen system. It analytically demonstrates that the Chen system has one heteroclinic orbit of Ši’lnikov type that connects two nontrivial singular points. The Ši’lnikov criterion guarantees that the Chen system has Smale horseshoes and the horseshoe chaos. In addition, there also exists on...