Consider a parabolic variational inequality with gradient constraint
min{vt-1/2σ2vxx-μvx+cv,vx-1}=0.
The problem stems from a stochastic optimal control problem based on optimal dividend model. By using PDE technique and the penalty method, the existence and uniqueness and some a priori estimates of the solution of the variational inequality are obtained, and then the properties of the free boundary are further discussed. It is proved that the free boundary can be expressed as a function of x with respect to t and is a monotonically increasing, C∞ smooth curve starting from zero.
GUAN Chong-hu
,
CHEN Jing
. A free boundary problem in variational inequality with gradient constraint[J]. Journal of East China Normal University(Natural Science), 2018
, 2018(1)
: 1
-10
.
DOI: 10.3969/j.issn.1000-5641.2018.01.001
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