I've not enough reputation to join the comment thread above, but there's a matlab script which implements Maranas and Floudas's 1997 algorithm to provide a (slowish) global optimum for an SP which you may find useful.
I've not enough reputation to join the comment thread above, but there's a matlab script which implements Maranas and Floudas's 1997 algorithm to provide a (slowish) global optimum for an SP which you may find useful.