Fig 1. The TIME^tm model technology growth cycle.

Top: Technology maturation is modeled as a best-fit, exponentiated logistic regression to the cumulative number of publications (N) over time. Bottom: The second derivative of this regression is used to identify the initiation point (point of greatest acceleration, d²log(N)/dx² = max) and established point (point of maximal deceleration, d²log(N)/dx² = min) for the technology. The initiation and established points bound a period of exponential growth, which subsequently slows as the technology approaches its limits.