1) It's not entirely clear why you would want alternatives for "evaluate" or "validate." In particular, "evaluate" and its various forms seem to fit well: "…to evaluate the capabilities of this model"; "one way of evaluating a different [type of] coverage is to ensure that the sum of the functions..." However, you could also use "to assess" and "of assessing," or (stretching the point) "ascertain" and "ascertaining," or (even more of a stretch, IMHO) "characterize" and "characterizing."

2) "…which doesn't always happen at the start…" or "…which is not always initially possible…" Mind you, "initially" and "at the start" are simply a logical guess as to the meaning of "à partida" here. More context would be enormously helpful.

3) "Iteration" has a specific meaning in scientific usage. It refers to an individual instance of an action, or of the execution of an instruction or procedure. ("Reiterations" generally refers to the repetition of actions or spoken words by humans.)

4) As the name of a branch of mechanics, yes, "dynamics" is always plural. (However, it is sometimes used in psychiatry, psychology, and sociology as a singular noun, synonymous with "behavior," as in "…taking continuing-education courses is often viewed as a wise career dynamic.")

Hope this helps!

1) assess or to study

2) a partida = at the first point,

3) interactions = interplays, connections,

4) dynamics is a noun here which is always in plural but it takes the verb in singular.

1) to examine, assess

2) a partida = at the first point, form the starting point

3) interactions = co-relations

4) dynamics is a noun here which is always in plural but it takes the verb in singular.

1.) Avaliar: besides "evaluate" you can use "rate", "appraise", "judge", "consider". All of these fit well in your text.

2.)à partida: at the start, from the start, initially, at first.

3.) iterations, repetitions. Iterations refers to doing calculations, or actions to converge into a solution to a difficult problem. Reiterations is to make a statement again, to say the same thing again.

4.) Dynamics as a noun is always plural, just like mathematics.

Cumprimentos e votos de boa sorte.
Luis M. Luis