Vertiport Operations Modeling, Agent-Based Simulation and Parameter Value Specification

Round 1

Reviewer 1 Report

The manuscript deals with vertiport operations modeling through the simulation and experts’ interview. It is one of the needed research to utilize the UAM. However, there are many things to be modified and check before publication. Therefore, I would like to recommend that it should be modified before publication.

Comments

1. There is no line number in the manuscript.
2. There are many errors on cited reference like Error! Reference source not found.
3. There are no correct section number in the manuscript like section 0.
4. Authors should put Figures’ number in the manuscript. There are many figures but I could not find out that which descriptions explains which figure. For example, Figure 1 shows … …
5. Authors used many regression methods such as exponential, cubic fit to know the optimum passenger delay. I would like to know how many samples authors used for the regression. I am wondering if such a small sample could give us reliable statistics. Therefore, authors had better describe the sample numbers for each simulation in the manuscript. And authors had better make a Table to show the best results for Figures(Figures 5 to 10).

Author Response

Dear reviewer, 
Thank you very much for your detailed and helpful feedback to our paper. We appreciate your investment! In the following we would like to respond to your points of suggestions.

Comment 1: Line numbers have now been added by the editor.

Comment 2: The reference errors occured in the editing process. The editor advised us to ignore theses errors for now, as they will be accounted for in the final formatting of the paper. 

Comment 3: The incorrect section number 0 is also part of the editing process. The editor advised us to ignore this formality in the review process, too. It will be acounted for in the final formatting.

Comment 4: All figures, which were not mentioned in the text (figures 1 and 5-10) have now been explicitly mentioned in the text.

Comment 5: The regressions, their equations and the coefficients of determination (R square) have been added to figures 5-10. It was unclear to us, what you mean by "sample size". It was further unclear, what the benefit of tabulating best results would be. Our goal was to show sensitivites and not to optimze one particular use case.

Please let us know if you would recommend further improvements to the presentation of results and indicate beneficial changes as detailed as possible. 

We hope the adaptions to our paper according to your comments are satisfactory! 
Kind regards,
Lukas Preis and Mirko Hornung

Reviewer 2 Report

The manuscript electronics-1633038 reports a vertiport model, consisting of three types of elements: pads, gates, and stands connected through lanes. The authors analyze the results obtained from the simulation and obtain important information about the analyzed model from experts.
The presented analysis and results are interesting, but there are a few points that should be clarified before I can recommend publication:

1) Page 22 - we have "In the following the evolution of the parameter list, which is discussed in section 0". The manuscript's file was not compiled correctly, and the sections references are incorrect (see page 24). Authors should read the entire article carefully.

2) Page 5, section 3.1. - we have "Demand profiles were randomly created from a normal distribution with its peak at the middle of the operational time (see Error! Reference source not found.)." As previously, the manuscript's file was not compiled correctly, and the references are not visible (see page 6).

3) Figure 2: the same diagram of the model we can find in the authors' earlier paper. Therefore, it is necessary to add a reference to this paper in the caption of the figure.

4) Figure 3: In the caption of the figure, the authors should add "Variation A".

5) Table 3: the description in the first row are not well visible.

Author Response

Dear reviewer, 
Thank you very much for your detailed and helpful feedback to our paper. We appreciate your investment! In the following we would like to respond to your points of suggestions.

Comment 1: The incorrect section number 0 is part of the editing process. The editor advised us to ignore this formality in the review process. It will be acounted for in the final formatting.

Comment 2: The reference errors occured in the editing process. The editor advised us to ignore theses errors for now, as they will be accounted for in the final formatting of the paper. 

Comment 3: The reference to the previous publication was added to figure 2.

Comment 4: The indication that the demand profile is "variation A" has been added to figure 3. 

Comment 5: The formatting was slightly adapted to make the header of table 3 more easily readable. The comment will further be accounted for in the final formatting by the editor.

Please let us know if you would recommend further improvements to the presentation of results and indicate beneficial changes as detailed as possible. 

We hope the adaptions to our paper according to your comments are satisfactory! 
Kind regards,
Lukas Preis and Mirko Hornung

Reviewer 3 Report

The paper aims to inform applied operations research in academia and start-ups in the industry, who concern themselves with vertiport design. Through expert interviews and agent-based simulation, this paper attempts to raise the fidelity of vertiport operations modeling. However, the authors should take into account the following aspects:

1. In the abstract part, the novelty and key idea of the proposed approach should be described. These are not clear. The authors only described that “This paper wants to increase the level of understanding of operational dynamics on vertiport airfields through agent-based simulation.” Of course, the reviewer can understand the aim.
2. The contributions are not clear. These should be better highlighted.
3. In the Introduction, the authors present various approaches from the literature. I think that a synthesis of the solution proposed in the literature depending on the type of analysis, advantages, and disadvantages is useful for readers. This synthesis can be given as a table.
4. Figure 1 is not explained in the text. The additional information should be introduced in the text.
5. The presentation of the methods and the empirical investigation parts are not adequate, with a lack of mathematical rigor. The authors assert in Paragraph 3 (Simulation results of Sensitivity Study) that “A quadratic fit approximates the data well’, “The best approximation is quadratic”, “A cubic fit approximates all three randomly sampled demand profiles nearly perfect”, “An exponential fit approximates the results well.” or “An exponential fit approximates the results near-perfect when demand profiles are studied separately”. But, these approximation functions are missing in Figures 5 – 10. The authors should represent these functions and the mathematical formula should be indicated.
6. The message “Error! Reference source not found” appears in the text (please see Section 3.1). Please verify and replace with the correct source.
7. Explain the notations from formula (1).
8. The Agent-Based Modelling and Simulation should be better presented in the paper.

 

Author Response

Dear reviewer, 
Thank you very much for your detailed and helpful feedback to our paper. We appreciate your investment! In the following we would like to respond to your points of suggestions.

Comments 1 & 2: Further clarifications of the novelty of the approach and the specifics of the contribution were added to the abstract. Further, the we would like to point the reviewers attention to the third paragraph of the section "Conclusion" ("The work of this paper..."), where the contributions are detailed.

Comment 3: Reviews of "Introduction" are inconsistent; both other reviewers judged the introduction to give sufficient background with no need for improvement. Please explain further what you mean by "various approaches" and indicate how listing them in a table would increase the understanding of the reader.

Comment 4: Figure 1 has now been explained in the text.

Comment 5: We included the missing fits, mathematical functions and coefficients of determination (R square) in the figure 5-10. The description in the text has also been adapted to present the figures more clearly.

Comment 6: The reference errors occured in the editing process. The editor advised us to ignore theses errors for now, as they will be accounted for in the final formatting of the paper. 

Comment 7: We included an explanation of the notation for equation 1 in the text.

Comment 8: The ABMS framework is described in detail in a previous publication. In order to prevent repetion, the framework was only described briefly in the main body of the paper. We would like to point the reviewer to appendix A for more details on the model and to the preceeding publication for further details: L. Preis, A. Amirzada, and M. Hornung, “Ground Operation on Vertiports – Introduction of an Agent-Based Simulation Framework,” in AIAA Scitech 2021 Forum, doi: 10.2514/6.2021-1898.

Please let us know if you would recommend further improvements to the introduction and the presentation of the methods and indicate beneficial changes as detailed as possible. 

We hope the adaptions to our paper according to your comments are satisfactory! 
Kind regards,
Lukas Preis and Mirko Hornung

Round 2

Reviewer 1 Report

I think that the manuscript was modified accordingly. Therefore, I would like to recommend that it would be accepted.

Reviewer 3 Report

The authors have tried and succeed to respond satisfactorily to each issue raised by the reviewer. They performed changes in the manuscript, and new explanations and elaborations of details have been brought.