Prof. Gnap is the head of the Department of Road and Urban Transport, which guarantees higher education in the study programs "Road Transport", "Transport Services in Passenger Transport", "Forwarding and Logistics", and the new study program "Expertise in Road Transport". He is currently a member of the Sector Council of Transport, Logistics, and Postal Services, whose activities contributed to the establishment of the National System of Occupations in the Slovak Republic. He is also a member of the working group for programming in the transport sector in the 2021–2027 programming period. He closely cooperates with professional practice with the Association of Logistics and Freight Forwarding of the Slovak Republic, where he is a member of the Board of Directors on behalf of associate members and is the chairman of the education and publishing section. He also cooperates with the Bus Transport Association and ČESMAD Slovakia, which is the association of road transport operators of the Slovak Republic. He is a responsible leader of several research projects and professional studies in the field of public transport, especially regarding plans of transport services of cities and regions and also plans of sustainable mobility. He is a member of the editorial boards of a number of domestic and foreign scientific and professional journals and a member of the scientific boards of international conferences in the field of transport and logistics.