I wish I knew a way as well. there are some curves here in my town that I take the lane on and can be doing over the posted limit, still get passed. the farther out into the lane I am the farther they go into the other lane. I have a horrible feeling that someday there will be a head on because someone passes on a blind curve. Usually when someone forces past me on one I get ready to dive off the road when they jerk back over when a car appears in the oncoming lane. That is how I was hit by a d-bag on a harley when he dove back over into me.
You will probably get a lot of advice telling you to take the lane more aggressively, which is fine but does not always work in some areas. That's why I have never bothered asking this question myself.