Oxygen, determination time constants, sensor

The experimental curve in Figure 3 demonstrates overshoot in the tissue oxygen response. It was determined previously (22) that a term representing pure delay along with the steady-state blood flow vs. arterial oxygen tension data would cause overshoot. In this investigation it was found that a first-order time constant delay would also produce overshoot. Therefore, since exact controller mechanisms are not being postulated, the flow controlled dynamics used in this study include pure delay and time constant lag. To consider the problem of sensor location, feedback and feedforward control loops were superimposed on the capillary-tissue model. 

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