The phrase "are simultaneously operating" is correct and usable in written English.
It can be used to describe two or more processes, systems, or entities that are functioning at the same time.
Example: "The two engines are simultaneously operating to ensure maximum efficiency during the flight."
Alternatives: "are working at the same time" or "are functioning concurrently".
In order to guarantee the operation reliability, and considering the flexibility of configuration, we may arrange 2 sets of wide area protection and control mainframes which are simultaneously operated and acted as standby for each other.
We believe that the present work, while involving a single film-based sensing microelement for demonstration purposes, also has implications for further efforts on transient analysis and array configurations where multiple types of sensors are simultaneously operated.
I went to a football school, which meant that I went to a university that served up education and was simultaneously operating a sports franchise.
By Susan Orlean November 7, 2011 I went to a football school, which meant that I went to a university that served up education and was simultaneously operating a sports franchise.
The Utah mayor who recently confessed that he wrote happy news stories about his town using a pseudonym, often quoting himself, was living a writer's… I went to a football school, which meant that I went to a university that served up education and was simultaneously operating a sports franchise.… A small, drowsy town in Ohio, a pile of dead Bengal tigers.
One big problem was Backplane was simultaneously operating offices in San Diego and in expensive Palo Alto.
There has been a change in policy concerning the number of CCDs that may be simultaneously operated.
The analytical model improved to calculate and generate switching intervals is simultaneously operated in DSP instead of managing a look-up table.
The EFD burst mode (Kasaba et al. 2017) is simultaneously operated, while chorus (EMIC) burst mode is operating.
