Evaluation of the Impacts of On-Demand Bus Services Using Traffic Simulation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper addresses the problem of optimising PT performance through a more flexible on-demand system in a specific area of Melbourne, Australia.

The introduction and literature sections are quite comprehensive, but they have some bias towards countries with low PT patronage. It seems that examples in Europe have been less explored. For example, what is said in line 38 does not correspond to most European cities, where bus lanes, intermodal interchanges, bus priority traffic regulations, etc, were settled in many cities since the 70s.  This bias also happens when the study area is presented (line 220) compared to a selection of cities. The comparison with megacities is useless because their mobility patterns are based on rail and metro supply. Paragraphs starting in line 158 refer to several trials, but they merit more specific details, like the city and modes included, to provide a clearer understanding of the research process.

I recommend explaining mobility patterns in the study area to justify its selection and adequacy for implementing on-demand services. Some information about modes and their patronage, problems, and limitations could be a good starting point for introducing flexible bus solutions. Some more information about MyKi smart card features and its penetration rate should be included.

Regarding results, the analysis is robust and validated with real data. However, a more detailed explanation of how on-demand services are tested against fixed routes is needed. The KPIs listed in Section 6 are correct, but are veh-km or veh-hours considered among them? This comment is because it is not clear if the cost of drivers is included in the analysis. This is normally one of the problems of minibuses and vans; they are more flexible but need more driver-hours with higher costs than regular buses. Table 10 does not explain if operation costs are included in the analysis.

The paper should finalise by proposing some conclusions that could be applied to other cities/contexts. Which conditions are required to consider flexible minibuses routes as a more efficient solution than normal bus services?

Reference 66 seems to be incomplete.

Author Response

Please see the attached file named "sustainability-3202155 - Review 1 Responses" for the point-by-point response to reviewer 1.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The article is devoted on the relevant topic of studying the modern approach to passenger transport management for organizing trips on demand request.  The study was carried out on real data from the Melbourne passenger transport network and its adequacy is beyond doubt.   The use of the micro traffic simulation method is indisputable for the implementation of the task.

As critical  comment, it is necessary to note the general overload of the article with information and the inconsistency of its content with the title.

The research presents the results not only of transport modelling, but also issues of reliability, quality of service, operational efficiency, network-wide efficiency and environmental impact.  At the same time, the methodology section deals exclusively with the issue of transport modeling.

To improve the perception of the article, it is recommended to present in the methodology section an integrated approach to solving the task, including evaluating the effects and to  reflect this in the article title.

 Another way  is to reduce the content of the article to solve only the task stated in the title of the article, that is, studying the issue of flexible dispatching and routing using historical demand for optimization of the service day.

I recommend the article for publication after this revisions.

Author Response

Please see the attached file named "sustainability-3202155 - Review 2 Responses" for the point-by-point response to reviewer 2.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Overall, this article is well written, detailed, well-presented and logical. This paper explains the impact modelling assessment of flexible on-demand transport using smartcard data from Melbourne's public transport network in an attempt to meet the increasingly diverse ridership needs of passengers, improve service provision and the passenger experience, and contribute to the sustainable development of the city. 

Specifically, advances in technology and business models brought about by digital platforms and mobile applications have created new opportunities for developers of alternative mobility solutions to complement the existing public transport system, progressively addressing new issues posed by the private car. On-demand public transport solutions, as a complementary solution to the problems posed by private cars, are suitable for low population densities, off-peak periods and holiday weekends, and provide a solid foundation for sustainable urban transport development. 

In addition, the important contribution of this paper is that the proposed on-demand service scenario improves the quality and efficiency of transport services, the passenger experience, the system efficiency, and reduces pollutant emissions. In addition, there is no significant difference between on-demand services and fixed schedule services in terms of trip completion rates, bus journey times or distances, providing an additional option to the knowledgeable traveller. 

In conclusion, the results of the study proposing on-demand service in this paper show that the combination of on-demand and fixed services can better meet the increasingly diverse travelling needs of passengers and help to make decisions about their benefits, cost savings and customer experience enhancement. Therefore, this option deserves to be further promoted for sustainable urban transport development. 

Since the paper is about the simulation of buses, I hope the author can mention the possibility of simulating a 3D bus in a high-fidelity environment, CARLA, in your literature review.   Thank you. 

Xiang, Y., Wang, S., Su, T., Li, J., Mao, S. S., & Geimer, M. (2021, November). KIT bus: A shuttle model for CARLA simulator. In 2021 IEEE Industrial Electronics and Applications Conference (IEACon) (pp. 7-12). IEEE.

 

 

 

Dosovitskiy, A., Ros, G., Codevilla, F., Lopez, A., & Koltun, V. (2017, October). CARLA: An open urban driving simulator. In Conference on robot learning (pp. 1-16). PMLR.

Comments on the Quality of English Language

see above

Author Response

Please see the attached file named "sustainability-3202155 - Review 3 Responses" for the point-by-point response to reviewer 3.

Author Response File: Author Response.pdf