"The Mathematics of Artificial Speech," by Alan Burdick. Discover, January 2003.
Alistair Conkie, AT&T's speech-synthesis expert, uses supercomputers that have amassed a vast digital warehouse of "phonemes" (voice sounds, including approximately 10,000 "t" sounds) to create artificial speech. Computer algorithms are created to smoothly string all the phonemes into words and sentences that "sound" the most natural. These billions of combinatorial decisions present a computer-processing problem for which Conkie is generally credited with devising a workable solution, called "unit-selection synthesis." He recalled the mathematics problem in which a travelling salesman must visit all 50 states in a limited time, choosing the least expensive route while maximizing sales coverage.
--- Annette Emerson