  Theoretical consideration of the propagation of femtosecond-Gaussian pulses
in a 1D composite medium, consisting of alternating self-focusing (SF) and
self-defocusing (SDF) waveguide segments with normal group-velocity dispersion
predicts the generation of trains of bright solitons when an optical pulse
first propagates in the SF segment, followed by the SDF one. The multiple
temporal compression (MTC) process, based on this setting, offers a method for
controllable generation of multiple ultrashort temporal solitons. Numerical
solutions of the generalized nonlinear Schr\"{o}dinger equation modeling this
system demonstrate that the intrapulse Raman scattering plays a major role in
the temporal and spectral dynamics. Collisions between ultrashort solitons with
different central wavelengths are addressed too. The paper provides, for the
first time, a procedure for producing controllable trains of ultrashort
temporal solitons by incident optical pulses propagating in a composite medium.
