Complexity theory is a fundamental branch of theoretical computer science that categorises computational problems according to their inherent difficulty and the resources required to solve them. At ...

The mathematics of symmetry, also known as group theory, is widely used as a tool in the solution of complex problems in many areas of theoretical physics, including string theory. A sequence of ...

In this paper, we address an interesting variant of the vehicle routing problem with time windows (VRPTW) faced by the China National Petroleum Corporation (CNPC). The CNPC owns a limited number of ...