Let A be the edge-node incidence matrix of a bipartite graph
\nG=(U,V;E), I be a subset of the nodes of G, and b be a vector such
\nthat 2b is integral. We consider the following mixed-integer set:
\n X(G, b, I) = {x : Ax ≥ b, x ≥ 0, x_i integer for all i ∈ I}.
\nWe characterize conv(X(G,b,I)) in its original space. That is, we describe a matrix (C,d) such that conv(X(G, b, I)) = {x : Cx ≥ d}. This
\nis accomplished by computing the projection onto the space of the x-variables of an extended formulation, given in [1], for conv(X(G,b,I)).
\nWe then give a polynomial-time algorithm for the separation problem for conv(X(G,b,I)), thus showing that the problem of optimizing a linear
\nfunction over the set X(G,b,I) is solvable in polynomial time.
\