i'm a little confused about the concept of this words. conceptual model, mental model, roadmap and framework. is there anyone who can explain to what this words means. and more importantly what is the difference of them?
Those are two sets of related but different concepts; mental/conceptual model, and framework/roadmap.
The difference between a mental model and a conceptual model is described well in this article.
Mental Model v Conceptual Model
A mental model represents a person’s thought process for how something works (i.e., a person’s understanding of the surrounding world). Mental models are based on incomplete facts, past experiences, and even intuitive perceptions. They help shape actions and behavior, influence what people pay attention to in complicated situations, and define how people approach and solve problems.
A conceptual model is the actual model that is given to the user through the interface of the product. Going back to the iPad ebook example, you have a mental model about what reading a book will be like in the iPad, how it will work, what you can do with it. But when you sit down with the iPad, the “system” (the iPad) will display what the conceptual model of the book app actually is. There will be screens, and buttons, and things that happen. The actual interface is representing the conceptual model.
Roadmap and frameworks are much broader terms, but I have put them into the UX context I think you're talking about - essentially your roadmap is your plan for how to deliver, and a framework is the set of constraints you have to operate within.
UX Roadmap v Framework
A UX Roadmap is a game plan to achieve your product or site goals. It starts with your desired result of a seamless and delightful user experience and takes into account all of the UX research required to achieve it. Think of it as a blueprint for your research that includes a strategic overview, the different kinds of studies needed to satisfy research goals, a proposed timeline of deliverables and other key elements that enable your success.
A framework is a set of functional, predefined, reusable components that can be bundled in a specific working solution.