  In this paper we address several constrained transportation optimization
problems (e.g. vehicle routing, shortest Hamiltonian path), for which we
present novel algorithmic solutions and extensions, considering several
optimization objectives, like minimizing costs and resource usage. All the
considered problems are motivated by practical situations arising, for
instance, in the mining and metallurgical industry or in data communication. We
restrict our attention to transportation networks with path, tree or geometric
structures, for which the developed polynomial-time algorithms are optimal or
nearly optimal.
