Hybrid artificial intelligent systems 13th International Conference, HAIS 2018, Oviedo, Spain, June 20-22, 2018 : proceedings - de Cos Juez, Francisco Javier; Villar, José Ramón; de la Cal, Enrique A.; Herrero, Álvaro; Quintián, Héctor; Sáez, José António; Corchado, Emilio (Springer, 2018)