I could be very pedantic here, but I'm actually trying to understand how this is different from a traditional engine.
In that sentence, what does the "required pressure" refer to? Presumably an elevated pressure is required, instead of a negative pressure? For what purpose? How is that pressure achieved? Is the pressure changed by a change in volume? Temp? Once the pressure has changed, does the gas do work on something?
You keep saying that, but it seems that you're only able to make sense of the article because you have some prior knowledge. I was hoping you would share that knowledge, but it seems you have no interest in doing so. What was the point of sharing the article then?
Since you seem to want to be reductive, it appears that this detonation engine is nothing more than a regular combustion engine with a fuel mix that is more reactive. That's great and cool, but it still isn't clear why this is any significant innovation.