When this design first showed up in China it was thought that the use of an advanced trimaran hull design demonstrated that the Chinese were able to incorporate advanced European and Australian fast ferry technology a bit faster than the U.S., as American programs to use these ships and this hull technology was then only in the design and experiment stage. While the U.S. did use some Australian designed fast ferries in the 2003 Iraq invasion, the U.S. was not yet building such ships itself. The trimaran hull configuration confers greater high speed capability in heavy weather, while providing a large deck space for multiple uses.
What might have halted Chinese work in this area was a shift in the last decade away from a coastal fleet (with lots of small, fast missile armed boats) to a high seas fleet with larger ships (like their recently launched carrier and new classes of large destroyers). Then again, turning their trimaran ship into "North Rescue 143" may simply be a way to see how the ship deals with some pretty rough waters over an extended period.