There is two meanings in the word 'streamline' in the dictionary, that is,

1 to give sth a smooth even shape so that it can move quickly and easily through air or water

2 to make a system, an organization, etc. work better, especially in a way that saves money

Can you tell me which one is suitable for the meaning of the 'streamlined' in the following sentence?

Manufacturers have many machines to choose from, including streamlined models specifically designed to produce one particular product.
I'm guessing neither of those.

It means models that do not have as many feature. It can produce one thing, and one thing only. Perhaps more elaborate models can be set to make many differing things. A steamlined model does not have what's sometimes called "The bells and whistles" (the extra stuff that is fancier, but make it a more deluxe product).
The required definition for that sentence:
streamlined: simplified

Another meaning:

To streamline someone: to fire him/her.
Students: Are you brave enough to let our tutors analyse your pronunciation?

There is suitable meaning.

I think 'up-to-date' seems to be closer to the point.

Thanks again.
No, there is no sense of it being up-to-date or more modern than the other models. It has fewer features and probably costs less.
Students: We have free audio pronunciation exercises.
 Marius Hancu's reply was promoted to an answer.
Thanks, Grammer Geek.

Thanks, Marius Hancu.

Thank you all.