How does LDS handle doctrine changes?

Starting from [this](https://christianity.stackexchange.com/q/62197/9158) question, I'm curious how the LDS church handles the doctrine changes. I saw a similar question (https://christianity.stackexchange.com/q/12381/9158) , but what I'm wondering is how this works in practice: - Let's assume a new idea comes. Who validates that the new idea is right or wrong? Is there a vote? - Where are these changes published? - What are some examples of doctrine changes? I expect to see them reflected in the [archives of the conferences](https://www.lds.org/general-conference/conferences?lang=eng) (or other official archives).