Dosen Jurusan Teknk Pertambangan UPR, Deddy NSP Tanggara ST. MT, megikuti seminar international (International Conference on Science, Engineering and Technology) ICoSET 2019 di Pekanbaru, Riau. dengan judul paper Judul : Assessment of Caking Characteristics Batu Ayau Formation Coal Based on Free-Swelling Index, Proximate and Ultimate Analysis Results