07/2016-08/2016, M2R, Seoul National University, supervised by YoungHee Kim and me. Following the bi-national workshop I organised with Sang-Mook Lee, we identified a few research directions, one of which was seismic imaging of the mantle beneath the Caroline plate. The challenge was to find a robust way to image the region of interest, since there are neither large earthquakes nor seismic stations (the plate is entirely covered by the Pacific). I suggested looking at the differential travel times between the S phase, which does not sample the region, and the SS phase, which reflects there. Hyoihn was extremely efficient during her short stay in Paris, which allowed us to present the first image at AGU 2016. We kept working together to refine the image and the interpretation: unfortunately it took much longer than expected, but we finally published the first paper on it. Hyoihn now works at an IT company in Korea.