  In this article we extend previous work by the authors, and elaborate further
on the structure of the general solution to the graviton and dilaton equations
of motion in brane world scenaria, in the context of five-dimensional effective
actions with O(\alpha ')$ higher-curvature corrections, compatible with bulk
string-amplitude calculations. We consider (multi)brane scenaria, dividing the
bulk space into regions, in which one matches two classes of general solutions,
a linear Randall-Sundrum solution and a (logarithmic) dilatonic domain wall
(bulk naked singularity).We pay particular attention to examining the
possibility of resolving the mass hierarchy problem together with the vanishing
of the vacuum energy on the observable world, which is taken to be a positive
tension brane. The appearance of naked dilatonic domain walls provides a
dynamical restriction of the bulk space time. Of particular interest is a
dilatonic-wall solution, which after appropriate coordinate transformation,
results in a linear dilaton conformal field theory. The latter may provide a
holographic resolution of the naked singularity problem. All the
string-inspired models involved have the generic feature that the brane
tensions are proportional to the string coupling $g_s$; it remains a challenge
for string theory, therefore, to show whether microscopic models respecting
this feature can be constructed.
