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The reduction of speed limits in urban roads through traffic calming schemes intends to ensure safer traffic conditions among road users by reducing the probability related to the occurrence of severe accident. Looking it from a different perspective, traffic calming measures can potentially resolve congestion problems at the same time by lowering the overall accessibility and attractiveness of private cars in urban areas. This study proposes a new methodological approach to explore and assess the direct impacts of traffic calming in the transport system efficiency of a metropolitan area. The multi-agent transport simulation (MATSim) and Open-Berlin scenario are utilized to perform this simulation experiment. By developing a new external tool, the free flow speed and road capacity of each network link is updated based on new speed limits and different compliance rates, which are defined per road hierarchy level. The test scenarios that are formulated present radical conditions, where the speed limit in most urban roads of Berlin drops to 30 km/h or even 15 km/h. The findings of this study show a considerably high increase in trips, passenger hours, and passenger kilometers using public transport modes, when traffic calming links are introduced, the reserve change is observed in private cars trips. Although the speed limits are decreased in inner urban roads in most of the scenarios, the decrease of average travel speed of private cars is not so high as it was expected. Surprisingly, private cars are used for longer distances in all test scenarios. Car drivers seem to use already existed motorways and private road to commute. In simulations, driver compliance to the new speed limits seems to be a determinant factor that is strongly influenced by the design interventions applied in a traffic calming area.

Modeling of Electric scooters (e-scooters) and prediction of their impacts in the transport system is challenging due to their dual drive behavior i.e., from vehicles’ roadway to pedestrians’ sidewalk. This study aims to develop a model to integrate e-scooter routing process in an agent-based model, namely: MATSim. The developed model is built on the hypothesis that perceived safety affects travel behavior of e-scooter users and is related to road environment. By performing a network analysis, links are classified in seven safety levels; these classifications are later introduced in the simulation process where agents balance safety with time and distance to make choices. Four network scenarios are simulated. The simulation outputs show that there are some distance thresholds for which e-scooter users are not willing to travel longer even if safety levels for such routes are higher.

The present paper intends to develop a method for evaluating the suitability of urban road networks to accommodate the movement of autonomous buses (ABs). The output of this process is the production of a detailed map indicating the score of each road segment in the network. To this end we follow a five-step methodological approach. The first step includes the examination of the current street classification, in order to identify functionality of the road network. The next step deals with investigating specific road network features such as slope, angle degrees in intersections, road surface width (excluding sidewalk) and existence or absence of medians in two-direction roads. After that we map the critical urban spaces or clusters in the study area and calculate their 250m isodistance zones, in order to detect clusters with high urban significance. The final step includes the process of evaluation. More specifically, the road network segments are evaluated through a simple formula, which is the suitability indicator that displays the appropriateness of the segments. The method is applied to the municipality of Kallithea which is a densely populated suburb in the southern part of Athens, therefore a favourable area for enhancing public transport. The suggested method describes a planning tool that can be utilised by policy makers and planners in order to promote sustainable mobility and the use of public transport in particular, improve travel conditions, enhance social equity and augment smartness in a long-term period. Lastly, the method can provide an adequate background for the potential integration of autonomous shuttle buses into the street classification system. This fact will facilitate their movement in the complex urban transport systems and will be a driver for shifting from conventional to smart cities.

During the past decades, unlike other countries of the European community, Greek society excluded bicycle from its everyday life, both as a solution for sports and recreation, as well as a transport mode. However, in the last few years, maybe due to the economic crisis, people in Greece began to consider cycling, again, in their daily routine. In this context, the present paper endeavours to examine and evaluate the ability to cycle in the complex urban environment of Greek cities. Therefore, this study develops a method for assessing bikeability, based on international literature and related walkability evaluation methods. Initially, a literature review was conducted to identify those parameters that positively affect the suitability of a cycling route. Afterwards, we developed linear scales to transform the quantitative data into scores ranging from 0 to 10, in order to be comparable. In the next step we used participative Analytic Hierarchy Process (AHP) in order to weight each parameter and identify its significance. Lastly, we formulated the final bikeability index. The chosen case study is the Municipality of Zografou, which constitutes one of the most significant municipalities in Athens, combining all aspects of a modern city: a liveable central area, university campuses, high residential density and traffic congestion problems. The results indicate that the overall bikeabilty index of Zografou is quite low, specifically it equals to 3,7/10 meaning that most of the road sections are not suitable or attractive for cycling. This paper provides fruitful insights about the issue of bikeability in urban areas and mostly its spatial dimension and it could be used as decision making tool for stakeholders and planners.

Safety concerns expressed by micro-mobility users seem to practically constrain the use and flexibility of these new modes. This paper introduces a new, parametric agent-based modeling approach for simulating micro-mobility, using MATSim as a platform. Perceived safety is introduced as a factor, which affects travel behavior of micro-mobility modes in a car-dominated, heterogeneous, and perceived unsafe road network. For the purposes of the paper, different scenarios are simulated, using the city of Athens, Greece as a test bed, to examine the model performance and applicability. A universal scoring function based on travel time, cost, and safety, is proposed. This paper also discusses the concept of unsafe discontinuities. Simulation results show that an unsafe road segment of 500 meters long is sufficient to induce evident behavioral variations and hinder the practical use of e-bikes and e-scooters in the base scenario. The establishment of a cycle-friendly road network leads to significant changes in the chosen routes and decreases the average trip distance for micro-mobility users. In this case, the simulation process is guided by perceived safety, primarily focusing on formulating safer paths for micro-mobility mode users. Nevertheless, the routing behavior of car users is not modified due to the spatial uniformity of safety perceptions in a car-dominated road environment.

E-scooter sharing services have grown exponentially in many cities of the world within the last 10 years, mainly with the goal to serve first/last mile trips. Compared to other shared mobility modes (e.g., autonomous buses and electric taxis), for which Agent-based Models (ABMs) have been applied in many cases, just a few studies attempted to simulate e-scooter trips. This study aims to bridge the gap between ABMs and e-scooter sharing services by reviewing the existing ABMs and conducting a qualitative assessment. Initially, existing ABMs are described based on ten descriptors. To test suitability of each model for simulating e-scooter sharing services, we developed an evaluation checklist based on empirical findings. The ten criteria refer to the capabilities of each model to (a) adjust in new challenges via an open-source code, (b) model shared mobility modes, (c) perform large scale simulation, (d) describe spatiotemporal variation of demand, (e) simulate bicycle, (f) pedestrian, and (g) mixed traffic (h) consider socio-demographic characteristics, (i) integrate new choice models, and (j) model multimodal trips. Our results reveal the advantages and disadvantages of each model in simulating flexible transport modes and services. We end up with a dilemma or a scalability problem: to model e-scooter riding behavior in link level or e-scooter services in network level. It is concluded that the dual behavior of e-scooter users (pedestrian or vehicle) poses new challenges that can be met through the development of new extensions or hybrid simulation models.