Keeping your slave chilled every once in a while will certainly keep her in line. Keep her in a cold room (about 15-20 degrees F) for about an hour, and when she comes out to warm up, she'll be more than willing to obey if it means getting warm. If that's not an option, try an ice bath. A little bit colder, since water saps heat faster than air, but just as effective if not more. Finally, if she's constantly disobedient without any sign of changing, try a snow burial. Tie her up, lay her out on the ground, and start shoveling snow onto her until she's buried up to her neck. 5 minutes of this will break her.