VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY LE ANH THU A TANDEM QUEUEING MODEL TO OPTIMIZE THE EFFICIENCY OF PUBLIC ADMINISTRATIVE SERVICES MASTER'S THESIS VIETNAM NATIONAL UNIVERSITY, HANOI VIETNAM JAPAN UNIVERSITY LE ANH THU A TANDEM QUEUEING MODEL TO OPTIMIZE THE EFFICIENCY OF PUBLIC ADMINISTRATIVE SERVICES MAJOR Public Policy CODE 8340402 01 RESEARCH SUPERVISOR Associate Prof PHUNG DUC TUAN Hanoi, 2021 Acknowledgements Two years of studying at Vietnam Japan University passed[.]