Lu, BingRuan, Lu2020-09-022020-09-022000-02-14https://hdl.handle.net/11299/215401Given a set N of n terminals in the first quadrant of the Euclidean plane E2, find a minimum length directed tree rooted at the origin o, connecting to all terminals in N, and consisting of only horizontal and vertical arcs oriented from left to right or from bottom to top. This problem is called rectilinear Steiner arborescence problem, which has been proved to be NP-complete recently. In this paper, we present a polynomial time approximation scheme for this problem.en-USReport