Integer Linear Programs are very useful on networking optimization problems. In some of this problems the integers variables are restricted to values {1,0}.
Some of the traditional problems in this variant are:
1. Grouping problem
Yi = 1 if location i is chosen,
Xij = quantity transported from i to j,
Fi = cost to establish factory i,
Cij = cost to transport from factory i to client j,
p = is limit of number of factorys established,
Uij = limit of quantity transported from i to j,
Ai = capacity to be transported in factory i,
Dj = demand of client j,
minimize: Z = ∑Fi.Yi + ∑Xij.Cij,
subject to: ∑Yi ≤ p,
Xij ≤ Uij,
∑Xij ≤ Ai.Yi ∀ i ∈ Z,
∑Xij ≥ Dj ∀ i ∈ Z
Xij ≥ 0 , Yi = {1,0}
Contains "either/or" constraints where a variable M which should approximate ∞ is added in order to make a constraint always true or always false in its inequalities.
another interesting studying aid:
Hillier, F.; Lieberman, G. & Liberman, G. (1990), Introduction to operations research, McGraw-Hill New York.
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