There are seven steps outlined under the Time History Analysis heading in the "Missing Mass and ZPA Correction" help topic for applying the ZPA option to force time history analysis. The discussion uses terminology that isn't defined in the help file. I would appreciate an explanation or example to clarify the seven-step process - in particular, the first four steps are unclear, leading to questions such as the following:

- Is the TIH load sum discussed in Step 1 algebraically adding the forces from all three directions at each node for each time step? If not, what is the method?
- Steps 2 - 4 refer to "discretized" and "undiscretized" loads. What is meant by these terms?
- Is Step 2 the absolute maximum of the result of Step 1 over all time points?
- Is Step 4 the envelope of the results of Steps 2 and 3?