I had an issue with bitting, hitting and i found there wasn't much that I could do to prevent it from happening. If the child was angry/frustrated, it was going to happen if i wasn't around. So I decided to have her always with me. If I was changing a diaper, she would have to come, and if I had to prepare lunch, she had to be there with me. This stage will pass and didn't find time outs to be working so I decided that prevention was the key. She is not old enough to communicate to another child with words so she gets her way but doing these things.
HTH!