دانلود رایگان مقاله انگلیسی مدل سازی سیستم های حمل و نقل با شمولیت خودرو های اتوماتیک - الزویر 2017

Abstract

Autonomous Vehicles (AVs) promise many benefits for future mobility. Several modeling studies investigated their potential impacts with special focus on spatial and/or socio-economic features. Spatial modeling represents (i) in detail the technical specifications of the novel mode, and ii) the spatial features of the area in which the system is implemented. Most of these models are agent-based. Socio-economic modeling addresses the conditions of market penetration and diffusion using mathematical methods with commercial or social orientation. Furthermore, it investigates investment and operating costs. This paper summarizes the main modeling works on transportation systems involving AVs that were published in the academic literature up to end 2016. In addition, we provide some examples of applications and address their respective outreach and limitations. We present recommendations for future developments. This way, the paper takes part to a research project of which the ultimate goal is to build a predictive model that can be used by operators and policy-makers in order to test AVs scenarios.

5. Conclusion: Outreach, limitations and some recommendations

This brief state of art in modelling transportation systems involving AVs is summarized in Figure 1. We observe that major models focus on the supply operations and set-ups without detailing the demand side beyond statistical and spatial description in the form of an origin-destination matrix of trip-flows.

On the supply side, agent-based approaches allow to assess AV fleet size required while optimizing the waiting time and empty VKT. Furthermore, these models permit to reproduce in a realistic, detailed and robust way movements of vehicles considering several strategies. However, studies considering the real network are very scarce (ITF, 2015; Adnan, et al., 2016; Anderson, et al., 2014; Azevedo, et al., 2016). Further, urban constraints which determine the locations of stations and their capacities are not considered at all, even in the case of electric vehicles. Similar to car sharing, two servic e configurations are possible: stationbased and free-floating. The free -floating configuration is employed for a broader variety of uses than the station-based one (Bereck, et al., 2016). The combination of fixed stations and free-floating (while respecting the conditions of accessibility (Ciari, et al., 2015)) could reduce waiting time and locating stations in low dense areas (which is also economically attractive). Using dynamic parking cost (relevant to area’s configuration and state of congestion) could be explored as well. Assignment strategies of vehicles to customers should be optimized as well. Indeed, almost all studies are based on a FCFS strategy; a strategy that could be optimized using heuristic insertion or simulated annealing (Jung, et al., 2013). In addition, all aforementioned models are applied on urban centres of cities. It would be interesting to explore the service potentialities in suburban zones, freeways and around major train stations.