Minimum activity level

Continuous production rate make. May be 0 (the plant is not operating) or between allowed production limits MAKEMIN and MAKEMAX

• Can impose using a semi-continuous variable: may be zero, or any value between the intermediate bound and the upper bound
• Mosel:

make is_semcont MAKEMIN
make <= MAKEMAX

• BCL:

make = prob.newVar("make", XPRB_SC, 0, MAKEMAX);
make.setLim(MAKEMIN);

• Semi-continuous variables are slightly more efficient than the alternative binary variable formulation that we saw before. But if you incur fixed costs on any non-zero activity, you must use the binary variable formulation (see Section Minimum activity level).