what is the proper way of displaing 2 activities working in parallel such as if:
1. Component 1 is riggered into Active State (1) and in turn it triggers Component 2 to Active State (2)
2. Now, both active states proceed in parallel.
3. Active State (2) completes somewhere in the middle of Active State (1), however, its timing does not affect Active State (1)
4. As a user I want to have an ability to achieve this using the "@+<time>" notations in the iuml