lunar and mars landing is a crucial part of any exploration mission. its importance is manifested by the considerable interest in the past couple of decades. solution of lunar descent can be either numerical or analytical. numerical solutions are iterative and computationally demanding and some of them might not be suitable for on-board implementation. on the other hand, analytical solutions ar...

‎In this paper‎, ‎we study translation invariant surfaces in the‎ ‎3-dimensional Heisenberg group $rm Nil_3$‎. ‎In particular‎, ‎we‎ ‎completely classify translation invariant surfaces in $rm Nil_3$‎ ‎whose position vector $x$ satisfies the equation $Delta x = Ax$‎, ‎where $Delta$ is the Laplacian operator of the surface and $A$‎ ‎is a $3 times 3$-real matrix‎.

In this paper, the kudryashov method has been used for finding the general exact solutions of nonlinear evolution equations that namely the (3 + 1)-dimensional Jimbo-Miwa equation and the (3 + 1)-dimensional potential YTSF equation, when the simplest equation is the equation of Riccati.

This was Presented in 5th International Congress of Iranian Iranian Society of Knee Surgery, Arthroscopy, and Sports Traumatology (ISKAST), 14-17 Feb 2018- Kish, Iran