Intelligent Information and Database Systems 11th Asian Conference, ACIIDS 2019, Yogyakarta, Indonesia, April 8-11, 2019, Proceedings, Part II - Nguyen, Ngoc Thanh; Nguyen, Ngoc Thanh; Gaol, Ford Lumban; Gaol, Ford Lumban; Hong, Tzung-Pei; Hong, Tzung-Pei; Trawiński, Bogdan; Trawiński, Bogdan (Springer International Publishing : Imprint: Springer, 2019)