Macroscopic Traffic-Flow Modelling Based on Gap-Filling Behavior of Heterogeneous Traffic
Round 1
Reviewer 1 Report
Very good article.
Author Response
The authors would like to that the reviewer for the positive feedback on their article. We are glad that the respected reviewer found our manuscript of very good quality.
Reviewer 2 Report
the paper written by the authors is structured in a clear and organized way. I recommend increasing the introductory part, referring to self-driving vehicles as everything can improve in the near future. I recommend reviewing the format of the references. to increase the bibliography especially by referring to future works. check the part of the conclusions, I suggest you describe them in a more extensive way.
the english language is quite clear and well written. check some typos in the text.
I recommend the following works to be included in the bibliography
Smart roads: An overview of what future mobility will look like
Trubia, S., Severino, A., Curto, S., Arena, F., Pau, G.
, , , ,
Decision tree method to analyze the performance of lane support systems
Pappalardo, G., Cafiso, S., Di Graziano, A , ,
Author Response
We thank the reviewer for the constructive feedback, which has improved the revised manuscript quite significantly. A detailed description of how we have carefully addressed each comment of the reviewer is attached in a separate file. All changes in the manuscript are highlighted and can be easily identified. We hope the revised manuscript addresses the reviewer's comments and hope it will meet the reviewer’s entire satisfaction.
Reviewer 3 Report
In this article, the authors conduct a study aimed at explaining the gap filling behavior in heterogeneous traffic flow using the effusion model of gas particles. However, I will detail some criteria to improve the article:
-The authors should write the acronyms correctly. The correct way is to write with the first capital letter referring to the acronym such as "Ordinary Differential Equation (ODE)". This error must be corrected in all the acronyms that the authors are using in the manuscript.
-The authors should separate the Introductory Section into two Sections. The first Section Introduction and the second Section Related Works.
-The authors should write correctly within a scientific article, the words "Section", "Equation", "Table", "Figure", "Algorithm". This error must be corrected throughout the document.
-I suggest to the authors to expand Related Works, starting with these articles:
-- Zambrano-Martinez, J. L., Calafate, C. T., Soler, D., Cano, J. C., & Manzoni, P. (2018). Modeling and characterization of traffic flows in urban environments. Sensors, 18(7), 2020.
-- Vallati, M.; Magazzeni, D.; De Schutter, B.; Chrpa, L.; McCluskey, T.L. Efficient Macroscopic Urban Traffic Models for Reducing Congestion: A PDDL + Planning Approach. In Proceedings of the Thirtieth AAAI Conference on Artificial Intelligence (AAAI-16) Phoenix, AZ, USA, 12–17 February 2016; pp. 3188–3194.
-Why have the authors not performed the study in a enviroment such as a city where there are more roads, or different traffic conditions?
-The authors should place a Figure of the scene or map, so that the reader has a clearer idea of the scene that is being studied.
-Why did the authors only develop the study for 30 seconds? This time is significant to perform a study?
-With the simulation time presented by the authors, how would it compare with a real situation?
-I suggest to the authors to place the two units (m/s and km/h) to give an easy understanding for the reader.
-In the presented scenario it contains all the traffic regulations, which includes distance between vehicles, traffic lights, signaling?
-The authors do not detail the number of vehicles injected into the scene to cause traffic congestion.
-Why have the authors placed the "time step" every 0.01s in the simulation?
-The simulation presented by the authors, how reliable is it to real traffic?
-The Figures presented by the authors, in their axes do not have the corresponding unit, this must be placed in each of the Figures.
-The authors should add more explanation in the Figures.
-Why do negative speeds exist? Does that happen in the real world?
-I suggest to the authors to add a Discussion Section.
-The conclusions have to improve, and include future work.
Author Response
We thank the reviewer for the constructive feedback and in-depth insight and criticism, which has improved the revised manuscript quite significantly. A detailed description of how we have carefully addressed each comment of the reviewer is attached in a separate file. All changes in the manuscript are highlighted and can be easily identified. We hope the revised manuscript addresses the reviewer's comments adequately and hope it will meet the reviewer’s entire satisfaction.
Author Response File: 
Author Response.pdf
Round 2
Reviewer 3 Report
Many thanks to the authors for having performed the different suggested changes. However, I would have loved to appreciate which unit is being handled in "Distance step" and "Time step", if it is meters and seconds respectively.
Author Response
We would like to thank the respected Reviewer for giving us the opportunity and feedback to improve our manuscript. We are deeply in his gratitude.
To answer the reviewer’s question, we would like to clarify that the “Distance step” is not the same as “Distance” in our manuscript and in the literature. In fact, the distance step is the number of steps, which is equal to “the total distance (100 meters)” divided by “the size of distance step (1 meter)”, which is why the distance step (or number of distance steps) is dimensionless.
Similarly, the number of time steps is equal to the “total simulation time (30 seconds)” divided by “the size of time step (0.01 seconds)” that equals 3000 time-steps, which is also dimensionless.
The same scheme has been followed in the simulations reported by many various researchers, for example, references 17, 20, 21, and 31 as cited in the manuscript.
