Optimizing the Sustainable Multimodal Freight Transport and Logistics System Based on the Genetic Algorithm

Round 1

Reviewer 1 Report

Author presented the “Optimizing the sustainable multimodal freight transport and logistics system based on genetic algorithm” . Here I would like to mention few suggestions for manuscript improvement .

1.      How MFTLS model will be benefited in today technology especially logistics-based applications

2.      In section 1.2 author mostly discussed very old references. Its major flaws in this article. Author could be discussed, and reference recent article published in the reputed journal in the area of multimodal freight transport.

3.      In Figure.1 author mentioned “SMFTLS” and FFTT. Author never abbreviated anywhere in the manuscript. Similarly, all the terms should be abbreviated once in the manuscript.

4.      At what basis MFTLS selecting the parameters and what is the characteristics ? also properties of parameters could be explained.

5.      We have seen all the figures look like copy and paste. So better all the figures could be re-draw in better quality with image enhancement tools

6.      In table.2,3 and 4 author used different performance validation metrics. Author must explain the performance metrics parameters and variable.

7.      In Figure 10. Axis description is missing in y-axis. Very poor quality view. Author must include original image with quality .

8.      Also author need to add accuracy level of proposed model in graph compare to existing models

Author Response

Response to Reviewer1 comments

1. The benefit of the SMFTLS model is stated in the conclusion lines 539-544 and section 1.3 in line 116-124.
2. Additional recent works on multimodal freight transport with their references from reputable journals are reviewed and included and some old ones removed in the revised manuscript.
3. The details of SMFTLS and FFTT has been explained in the text (where they were first mentioned) and all terms are abbreviated once in the manuscript, lines 117 and 220 respectively.
4. The basis of SMFTLS selecting the parameters and the characteristics of the parameters, and the explanation of the properties of the parameters were established in table 1 line 251.
5. The images are currently re-drawn with better enhancement tools.
6. The meaning of the performance validation metrics and variables used in table 2,3 and 4 are defined in line 321-325.
7. The graph in figure 10 is correctly drawn in the revised manuscript line 520.
8. The accuracy level of the proposed model graph in comparison with existing models is not considered as part of author’s objectives. However, it could be a useful investigation in future studies. Hence, it is stated as a limitation and for future researchers consideration, lines 589-590.

Reviewer 2 Report

1) The main contributions need to be listed in the introduction before last paragraph by dot.

2) The limitation of previous literature needs to be considered.

3) Add a table in the literature review section which includes the advantages and disadvantages of previous works and also describes the limitation in this field to show how the suggested method solve it.

4) Edit the parameters name in Tables 1 and 6 instead of taking screenshot.

5) recheck the font foe example page 7 line 288 "mode l in city" has not the same font.

6) All formulas in the text need to be typed. check all the paper and type the formulas.

7) Check the font of all formulas and type them in a similar shape.

8) Page 14 line 458, the formula needs to be numbered.

9) Increase the quality of the figures, for example figure (9) has a low quality.

10) Table 12 needs to be checked, what is the numbers in second row.

11) Compare the method with other exiting methods to show the efficiency of your suggested method.

12) Add a comparison section and compare with other methods

13) References 14 to 19 are self citation, its not scientific to use more than 2 self citation papers.

 

Author Response

Response to reviewer 2 comments

1. The  contributions worked on were stated in line 66 and other sections in the manuscript e.g. introduction and conclusion.
2. The limitations of previous  literature works were reviewed in sections 1.1 and 1.2.
3. Authors could not specifically tabulate advantages and disadvantages of previous works but these were considered in the empirical studies reviewed in the relevant literature.
4. Parameters names in tables 1 and 6 are modified to be editable instead of the screenshots.
5. The fonts are rechecked and edited to be the same (for eg. ‘mode l in city i).
6. All the Formulae in the text are re-typed to be editable equations (1-5) in lines 261-268 and 477-478.
7. The font of the formulas are currently typed in the same shape.
8. The formula in page 14 line 458 is currently numbered as ‘(5)’ in lines 477-478 of the revised manuscript.
9. The quality of the figures, e.g. 9 is currently increased in line 498-500.
10. Table 12 is double checked to be correct. The numbers in the second row indicates the cost of transport in $ by rail in the distance covered for the respective days as indicated.
11. The comparison of existing model with our proposed model is stated.
12. Authors did not add a comparison section but suggested for future research consideration stated in lines 589-591.
13. The self citation in former references 14-19 is currently limited to two papers references No.7 and 10.

Reviewer 3 Report

FORMAL COMMENTS:

- Add further developments in abstract and Conclusions.

- Add the meaning of acronyms MFTLS, MFTL and SMFTL and choose only one, as there is no need of 2 different terms for the same subject.

- Write "TD" (instead of "D") in line 138.

- Bad references in lines 105 and 196 (year is missing).

- The word "ply" in line 204 seems to be wrong.

- Improve format of tables 1, 5, 6 and 12 (this one has a serious mistake in the line about Total costs).

- Improve format in equations 1, 2, 3, 4.

- Correct to Figure 5 in line 367, Figure 7 in line 445, Table 12 and Figure 10 in line 500.

- Harmonize the name of the first author in citations in lines 524 and 536.

- In the section of references, citations should include all the authors, and not to use the "et al".

- The link to get the white paper is missing in reference in line 4 (line 573).

- The number of the journal Financial times is missing in the reference number 11 (line 589).

- Add a reference in line 411 regarding the "sorting selection method" , and another in line 418 regarding the "roulette method".

- The "C" in the square in figure 7 should be "B", and in the third chromosome "a" should be replaced by "b". - The obtaining of the last individual, which should be "E" is not clear.

- The program and version used for the analysis should be mentioned in section 4 or 5, not only in abstract and Conclusions.

- Clarify in table 12 what is the initial situation which has been considered in the optimization problem (a saturation flow of rail per day belonging to 10?).

- Text in lines 293 to 298 is not clear and it needs to be reformulated.

CONCEPTUAL COMMENTS:

- Justify the selection of the GA methodology to solve the problem. Why not to choose other multiobjective optimization methods (for example the Mixed-Integer Linear Program)?

- Why the concept of roles is introduced? (Lines 160 to 174). They are not used in the GA algorithms. Explain the reason of this concept or remove.

- Figure 2, 3, 4 should be harmonized with the same nodes and with different distances between nodes according to the mode of transport. Tables 2, 3, 4 should be also integrated in these harmonized figures.

- Why transportation volume show in table 5 is only addressing the Tema port? Does the optimization model takes this port always as the Origin? Please clarify this concept.

- The Selection operator is described in (a) section 4.2, and the Crossover operator is described in (b), but the Mutation operator is not described in the paper.

- Why symbols in Figure 8 about the amount of traffic between cities are not numbers as in Figure 9?

- The last text of Conclusions is not well connected with results of the paper. These conclusions are not directly obtained from them.

- Reductions in time and carbon emission mentioned in lines 505 and 506 don't seem to appear in Figure 10 (brown and grey lines).

Author Response

Response to Reviewer 3 comments

FORMAL COMMENTS:

1. Further developments are added to the abstract and conclusion.
2. The full meaning of the acronym ‘SMFTLS’ is added at where it was first mentioned in the abstract, and main body in line 117 of the manuscript, also  all other related names and abbreviations in the text  are limited to only SMFTLS in the revised manuscript as advised.
3. ‘TD’ is written to replace ‘D’ as advised.
4. The correct in-text referencing is currently done in the revised manuscript.
5. The word ‘ply’ used in line 204 is currently changed in the revised manuscript.
6. The formats of tables 1, 5, 6, and 12 are improved.
7. Formats of equations 1,2,3,4, and 5 are improved by rewriting them  to be editable.
8. The figures 5,6, 7 and table 12 are correctly modified to be visible enough.
9. Texts in lines 293 to 298 is reformulated to be clear in the modified manuscript.

Conceptual comments:

1. The reason for selecting GA optimisation instead of other multi-objective optimisation  methods is justified and explained in lines 377-380.
2. The concept of roles introduced in lines 160-174 is removed from the modified manuscript  since its not used in GA algorithms as you rightly advised.
3. Unfortunately the figures 2,3,4 and tables 2,3,4 cannot be harmonized with the same nodes with different distances between nodes since each of the transport modes (road, rail and waterway) has different links with rail and waterway having fewer nodes  than road network.
4. Yes the optimization model always considered only Tema port as the origin and this is stated in the manuscript lines 318-320.
5. The last text of conclusions is connected with results of the paper. These measures are necessary for adopting the SMFTLS as an alternative to the existing transport and logistics system with limited infrastructure  as bottlenecks.
6. Reductions in time and carbon emission shown in Figure 10 (brown and grey lines) appear at the bottom part of the graph, line 520.

Round 2

Reviewer 1 Report

Thanks for revision.

Author Response

The Reviewer 1 is fully satisfied with the first revised manuscript and stated no comments for revision other than ‘Thank you for the revision”

Authors wish to thank you too for your constructive review and suggestions for the first revision to improve our manuscript for possible publication in Sustainability journal.

Reviewer 2 Report

The authors revised the paper well but there is some comments that should be edited and the paper needs to be double check carefully.

1) Page 4 line 153, write figure instead of fig to make all the paper in a similar form.

2) Page 14 line 452, Edit the text, what do the authors mean of "Figure 6.7"?

3) Figure 9 is not cited in the paper, cite figure 9 in the paper.

4) The quality of figure are increased except figure 9, redraw figure 9 and also type Qij in figure 9.

5) Tables 8, 9, 10 and 11 are not cited in the paper, cite these tables in the paper.

Author Response

1. Fig is replaced with figure in page 4 line 153, currently line 160.

2. Figure 6.7 is edited to be figure 7 currently line 477.

3. Figure 9 is currently merged with figure 8 and is now renamed as figure 8 and cited in the paper line 504-505.

4. The Quality of figure 9 which is currently renamed as figure 8 is increased and also Qij in figure 9 typed in line 506.

5. Currently the tables 8,9,10 and 11 are cited in the paper.

Reviewer 3 Report

Thanks for considering most of my comments. However there are still some peding points:

- GA is Genetic algorithm and not "Genetic arithmetic" as stated in line 15 of the revised manuscript.

- Citations with more than one author should be written as "Okyere et al." and not "Okyere and Yang et al."

- The justification of the selection of GA in lines 367 to 370 over other multiobjective optimization methods is not clear. It would be recommendable to briefly explain other multiobjective optimization methods and explain the reason of selecting this one.

- Figure 7 is not done according to the text explained before, as for example the individual "C" is not created with the first part of A and the second part of B as stated in lines 449 and 450 (by the way replace Figure 6.7 per Figure 7 in line 452.

- Remove words: "Future Studies" in line 582.

-The next previous comments have not been addressed yet by authors:

- Add a reference in line 417 (new version) regarding the "sorting selection method" , and another in line 424 (new version) regarding the "roulette method".

- Clarify in table 12 what is the initial situation which has been considered in the optimization problem (a saturation flow of rail per day belonging to 10?).

- The Selection operator is described in (a) section 4.2, and the Crossover operator is described in (b), but the Mutation operator is not described in the paper.

- Why symbols in Figure 8 about the amount of traffic between cities are not numbers as in Figure 9? (In other words, why the manuscript needs Figure 8 and Figure 9. They could be merged in only one figure).

- The last text of Conclusions is not well connected with results of the paper. These conclusions are not directly obtained from them: I meant here that some recommendations are not well supported on the basis of the results of the paper. For example, why are you suggesting to increase the density of specific cities as Accra-Koforidua, Accra-562 Cape Coast, Accra-Tema and container railways in Ghana. What concrete result in your paper is supporting this aseveration? 

Thank so much for your consideration.

Author Response

Authors wish to thank you too for your in-depth knowledge shared and constructive comments and suggestions to improve the quality of our manuscript for the first and second revisions for a possible consideration for publication. Hope the following additional responses may answer your comments and suggestions;

 1. GA is now rewritten as genetic algorithm but not ‘genetic arithmetic’ as formerly written in in lines 17.

2. Okyere and Yang et al. is currently corrected to Okyere et al.in lines 579 and 591.

3. Further explanation for selection GA over other optimisation methods are added in lines 385-387.

4. Figure 6.7 is replaced with figure 7 line 477.

5. Future studies is removed in the previous line 582. which is otherwise supposed to be at line 620.

6. Reference is added to each of the methods in lines 434 and 441 respectively.

7. The initial situation is clarified in lines 532-534 which is considered in the optimisation problem.

8. The mutation operator is described in section 4.2 (c) lines 469-476 of this second revised paper

9. The figures 8 & 9 are currently merged as one (Figure 8) as you rightly suggested, as indicated in line 504-505.

10. The last text of conclusions are inferred from the study and its currently explained better in lines 600-602 “Example, the density of railway container trains linking Tema-Accra-Cape Coast-Takoradi and other cities with railways in Ghana as shown in figure 8 must be increased’. These are cities where the railway links are available in Ghana transport network system which need further development to meet the increasing demands.

However, authors can remove these part of the conclusion by your advise if they are still not clearly supported by the results of the study.