I'm doing a market study on the monitoring systems that are most used, but I'm here with some research problems, I am not finding information about projects that are used in monitoring systems such as: Zabix, Nagios, OpenNMS, etc

I found a very funny example of a company in Tokyo that had the idea of ​​connecting a Geiger counter (which measures certain radiation) on a computer and collect the radiation levels emitted by the Fukushima nuclear plant so online and publish them on the internet. The software that made the monitoring, collection, storage and publication of radiation levels was Nagios.

But I just found this example. I found several "global" things but specific examples like this I found none.

Does somebody could give me information from other projects?

Best regards