Algorithms and Logical Networks.

There were two principal problem domains explored under this contract. The first concerns the properties of connecting networks. New results are reported which show that reducing the demand on a connecting network from never blocking to blocking only with very small probability leads to a large reduction in the number of switches required. The second concerns the complexity and efficiency of source coding schemes, including universal schemes. It is shown that a decoder for an efficient source code need never be very complex. It is also noted that there are simple coding procedures for infinite sets like the integers, whose efficiency is good no matter what the distribution of probabilities of source symbols is.