The Steiner problem for a transportation network on a surface specified by a digital model

The paper is concerned with design of a network which relates the drains and the source and has a minimum network building flux transformation costs for an amount which satisfies the needs of drains. The surface on which the network inhomogeneous in terms of specific construction costs is deployed is specified by a digital model of the surface. The network can fan out in any points of the model. Some properties of such networks are described. Several heuristic design techniques are proposed. Results of computer tests of design algorithms are given.