How do I train an aggressive min pin? ?

The love of my life is my 2 year old miniature pinscher. The problem is that, although she loves me and a few close friends to death (enough to happy squirt when she sees them) she does not fair well with strangers. She will attempt nipping and does not stop barking and jumping at them. She is also IMPOSSIBLE to take to the dog park and goes viscous on other dogs when they come up to her. How can I stop her aggression? I've tried everything!