Promoting Liquefied Natural Gas (LNG) Bunkering for Maritime Transportation: Should Ports or Ships Be Subsidized?

Round 1

Reviewer 1 Report

1. In the abstract, the relevant, unique, and quantitative results should be presented.
2. Lines 16-18. Authors wrote, „Despite the influence of the pandemic, the global average temperature would rise more than 3◦C in this century…”. How the Covid pandemic affects global warming?
3. The important remark is related to the design of the paper. I found a strange problem with the quality of all tables and equations (all equations should be numbered). Please check carefully the formatting of the text of the manuscript for compliance with the requirements of the Journal.
4. A case study concerns the application of the proposed method of subsidy plan should be presented
5. Lines 35-37. Wikipedia should not be cited in scientific articles.I suggest the authors include some references instead of Wikipedia like e.g. https://doi.org/10.1016/j.jlp.2012.07.020; https://doi.org/10.1016/j.psep.2017.08.026
6. Define better conclusions, it should vary vague and support better what the innovation is, the unique finding of this work as compared to similar works in international literature done through the years. The conclusion should better reflect the content of the paper and the main results.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript entitled " Promoting liquefied natural gas (LNG) bunkering for maritime transportation: Should ports or ships  be subsidized?" is an immature approach  that requires major revisions in order to be reconsider for possible publication in your journal. 

Comments:

• The abstract should be concluded with remarks that are supported by results; 
• The manuscript does NOT contain all the key elements that define a well-structured paper: introduction, study objectives, methodology, results and conclusions;
•  The research questions  are NOT clearly defined in the state-of-the art-context. The manuscript does not describe issues such as data collection  and  investigation methods;
• The authors do NOT give enough insight into the presentation and discussion of results so as to support the research questions;
• The conclusions are completely inadequate; 
• A lot of abbreviations( UNCTAD,IMOGHC, etc.) are not explained;
• Line 27-29: However, with the recovery of world economy, the global
  28 maritime trade volume is expected to increase by 4.3% in 2021.What does that means? It's  the end of April 2022
• Line 36-37:Wikipedia is given as reference. I think that the authors could find more relevant references;
• Line 120-121: For more detailed review, please refer to Peng et al. (2021). This sentence must be reformulated

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

In this paper the authors consider two-stage subsidy plans and established a mathematical model to find the optimal subsidy plan under different scenarios.

The topic per se is interesting and the authors have done a reasonable job of conducting the research work.

The presentation of the main results is clear and comprehensive. From a formal point of view, all the contents seem to be correct and proofs complete. The results are valuable taking into account their possible applications in maritime transportation.

Although is a good paper, it got some issues which can be fixed in light of the following suggestions.

In the Introduction, you need to connect the state of the art to your paper goals. There are many details that are not related to the objectives of the paper. 

Please improve the literature review. This should clearly show the knowledge gaps identified and link them to your paper goals.

The „Conclusions” should be further developed in order to explain in detail the main findings. What are the implications of these findings? What are the main differences between these findings and the others available in the scientific literature?

Overall, I evaluate the study very positively and the above-mentioned shortcomings are in principle minor. 

 

Author Response

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Author Response File: Author Response.pdf

Reviewer 4 Report

1. It is better if the presentation of this report is arranged in a better way, for instance:

• Row 268: are the table 1 and table 4 correct? we recommend that an explanation for each table be made directly below the table
• Article 3.4 name's; Article 4.3; and Article 5.3 found with the same tittle
• The narrative of the formula that has been written in the Proof section, should be arranged as a mathematical expression of decent, so that it is easier to understand

2. Could you make a short narrative related to previous researchers so that you could explain the differences with the findings in this paper

3. There are 3 objectives of this paper but the results are not clearly stated in the conclusion. To explain and answer, should ports or ships be subsidized? 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors have very well respond to all my comments and the manuscript can be now accepted for publication.