The development of the aviation world in recent years has increased, one which is field unmanned aerial vehicles. This line with increasing use UAVs various fields, including for military missions, natural disaster monitoring and photography missions. Many types aircraft that can be used to complete these type widely flying wing aircraft. triangular shape does not have a tail. controller uses e...

Ducted-fan tail-sitter unmanned aerial vehicles (UAVs) provide versatility and unique benefits, attracting significant attention in various applications. This study focuses on developing a safe reinforcement learning method for back-transition control between level flight mode hover ducted-fan UAVs. Our enables transition with minimal altitude change time while adhering to the velocity constrai...

It now seems probable that the version of de Sitter spacetime which may ultimately emerge from string theory will not be the familiar, maximally symmetric version, since it is likely to be truncated in some way by metastability or otherwise reduced in symmetry so that its isometry group has finite-dimensional representations. We argue that the best way to gain some control over this situation i...

the study of flight vehicle structures reveals the importance of obtaining the most suitable accuracy compatible with construction. for this purpose, several experiments were conducted at the agard institute. in this paper the results of one such experiment performed on a sample airplane wing are presented. aircraft structural engineers use several methods to model these structures. specifing h...

We explore aspects of the physics of de Sitter (dS) space that are relevant to holography with a positive cosmological constant. First we display a nonlocal map that commutes with the de Sitter isometries, transforms the bulk-boundary propagator and solutions of free wave equations in de Sitter onto the same quantities in Euclidean anti-de Sitter (EAdS), and takes the two boundaries of dS to th...