Twin Cities commuters are getting used to a modified system of ramp meters. Many of the meters were turned back on Friday afternoon with a few changes. Sixty of the meters typically used in the mornings and 63 of those typically used in the afternoons remain off. The meters are also on for a shorter period of time, and the maximum duration between green lights is shorter. Before Friday, the meters had been turned off for almost eight weeks as part of a study of their effectiveness. Mike Sobolewski is the Project Manager of the Ramp Meter Study for MNDOT. He's that yesterday wasn't a good day to base any decisions on.