Heuristics for Improving Trip-Vehicle Fitness in On-demand Ride-Sharing Systems Topics: Analytics for Intelligent Transportation; City Mobility and Ecodriving; Information Systems and Technologies; Public Transportation Management; Systems Modeling and Simulation; Urban Mobility and Multimodal Transportation In Proceedings of the 4th International Conference on Vehicle Technology and Intelligent Transport Systems VEHITS - Volume 1, 323-334, 2018 , Funchal, Madeira, Portugal