Inverse spectral problems for the Sturm-Liouville operator with discontinuity

In this work, we consider the Sturm-Liouville operator on a finite interval $[0,1]$ with discontinuous conditions at $1\mathrm{/}2$. We prove that if the potential is known a priori on a subinterval $[b,1]$ with $b\ge 1\mathrm{/}2$, then parts of two spectra can uniquely determine the potential and all parameters in discontinuous conditions and boundary conditions. For the case $b<1\mathrm{/}2$, parts of either one or two spectra can uniquely determine the potential and a part of parameters.