Smart Cities, Green Technologies, and Intelligent Transport Systems 9th International Conference, SMARTGREENS 2020, and 6th International Conference, VEHITS 2020, Prague, Czech Republic, May 2-4, 2020, Revised Selected Papers - Klein, Cornel; Helfert, Markus; Berns, Karsten; Gusikhin, Oleg (Springer International Publishing, 2021)