Artificial intelligence applications and innovations 15th IFIP WG 12.5 International Conference, AIAI 2019, Hersonissos, Crete, Greece, May 24-26, 2019 : proceedings - MacIntyre, John; Maglogiannis, Ilias; Iliadis, Lazaros; Pimenidis, Elias (IFIP Advances in Information and Communication Technology, 2019)