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Figure 2, A and B, shows the normalized effluent turbidity vs. time during the settling state for Spring 2009 team's experiment and Fall 2009 team's experiment, respectively. In both cases, the turbidity of the water decreases rapidly. Moreover, we can observe that for low flow rates, the turbidity decreases more rapidly and the residual turbidity is lower in both experiments. Figure 3, A and B, represents the normalized turbidity as a function of Vs. As Vs is the inverse of time, we observe the opposite trend in the data. Figure 4, A and B, shows the cumulative distribution function and figure 5, A and B, show the resulting probability density function (PDF) of settling velocities obtained from the fitted gamma distribution for Fall 2009 experiment and Spring 2009 experiment. We can observe on the PDF curves that in both cases the mean velocities are decreasing with the flow rate (trace 1 being the lowest flow rate and trace 8 the highest).
A 
B
Figure 2:Plot of the normalized effluent turbidity (NTU) vs. time(s). Experiment of 5/13/2009(A). Experiment of 9/24/2009 (B)
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