Those are a very smart dog. A professional trainer or going to classes with the dog would help tremendously. If you are only gone for a few hours at a time, kennel the dog. I do that with my yellow lab and she loves her kennel.
I agree.. the dog needs to (and wants to) understand who is in charge. Praise is critical, but I have "corrected" a dog by physically lying gently on top as I firmly talk with her. Not to an excess--not violent but to make a point. Sortof speaking to her/him in dog terms. Has worked for me. And you form a good bond with each other. If you bond, your dog will want your leadership and to please you. So reward the good with great praise..