Is calculus ever used in scale design?

[Ron Nossaman]

> Greetings,
>  
>         Why? For the most accuracy that can be obtained, as far a string 
> vibrating is conerned. Presently, strings take zero friction (as far as 
> vibrating/moving through the air) into consideration, yet /because/ of 
> the air, sound waves can be heard,. To me, you cant have it both ways.  
>  
> Julia

How would the use of calculus do this, and to what benefit 
beyond the "standard" set of scaling formulae? Give me an example.
Ron N