  We extend the one-dimensional, two-zone models of long-term protostellar disk
evolution with infall of Zhu et al. to consider the potential effects of a
finite viscosity in regions where the ionization is too low for the
magnetorotational instability (MRI) to operate (the "dead zone"). We find that
the presence of a small but finite dead zone viscosity, as suggested by
simulations of stratified disks with MRI-active outer layers, can trigger
inside-out bursts of accretion, starting at or near the inner edge of the disk,
instead of the previously-found outside-in bursts with zero dead zone
viscosity, which originate at a few AU in radius. These inside-out bursts of
accretion bear a qualitative resemblance to the outburst behavior of one FU Ori
object, V1515 Cyg, in contrast to the outside-in burst models which more
closely resemble the accretion events in FU Ori and V1057 Cyg. Our results
suggest that the type and frequency of outbursts are potentially a probe of
transport efficiency in the dead zone. Simulations must treat the inner disk
regions, $R \lesssim 0.5$ AU, to show the detailed time evolution of accretion
outbursts in general and to observe the inside-out bursts in particular.
