  We further investigate the dimensional duality (D-duality) proposed in
arXiv:0705.0550 by mainly focusing on the properties of D-branes in this
background. We derive the world-sheet correspondence of static D-branes, and
discuss the fate of non-static D-branes from the world-sheet viewpoint. The
quantum string production with or without D-branes is also studied from the
time-like Liouville theory. We find that the closed string production from the
background is much larger than that from D-branes decaying into nothing.
