From a quick review of Masters' dissertation requirements, it appears
that the common requirements are that it must be based on a working program and must have a practical application.
The JEE vs RoR sounds like a good candidate, provided it is well thought out and the problem being solved is sufficiently practical.
Points to compare: * cost effectiveness of vertical scaling * cost effectiveness of horizontal scaling * product development cycle time * development cost * maintenance cost * ease of testing, and impact of testing on overall cost
I hope this helps.