Abstract: | One of the techniques known as the Polygon-to-Chain reductions for computing the terminal reliabilities of networks with perfect vertices is generalised for computing the terminal reliabilities of networks with imperfect vertices. The necessary reduction formulas and new vertex/edge reliabilities are established. Consequently, the terminal reliabilities of any series-parallel network with imperfect vertices can also be computed in linear time. This extends a result of Satyanarayana and Wood on the case where all vertices are perfect. |