The figure below shows a direct current electrical
network. A mathematical programming model can be used to find
the current flows I1, I2 and I3.
The current flows are the variables of the model.
a. The model requires the single constraint:
Explain the purpose of this constraint.
b. Write the nonlinear objective function that when minimized
will determine the values of the currents.
c. When the model is solved with a procedure such as the
Solver in Excel, is one assured of global optimum? Justify your
conclusions based on the constraint of part a and the objective
of part b.