Seepage–Deformation Coupling Analysis of a Core Wall Rockfill Dam Subject to Rapid Fluctuations in the Reservoir Water Level
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn this paper, authors have reviewed the impact of rapid fluctuations in reservoir water level at pumped storage power stations on core wall rockfill dams. These dams play a crucial role in energy storage and release. The research investigates the following aspects
1. Deformation and Settlement
2. Sensitivity to Water Level Changes
3. Horizontal Displacement and Settlement
4. Seepage Line and Earth Pressure
5. Overall Settlement
This review is interesting and well-organized and is suitable for publishing after minor revisions, some of which are mentioned below:
1. There are some typos in this article. For example:
In abstract, instead of “ both upstream and downstream side” should be “both upstream and downstream sides”
In introduction, instead of “finite element software was employed in this study to analyze changes”. Consider changing it to “finite element software is employed in this study to analyze changes”.
In seepage-stress coupling theory, boasting a maximum height of 50.4 meters”: The word “boasting” may not be the most appropriate choice. Consider using a more neutral term: “with a maximum height of 50.4 meters.”
In seepage-stress coupling theory, “The slope of the upstream side is designed at a ratio of 1:2.0, while the downstream slope follows a ratio of 1:2.5”: Consider rephrasing for clarity: “The upstream slope is designed with a ratio of 1:2.0, and the downstream slope has a ratio of 1:2.5.”
In analysis of seepage field, In the sentence “The correlation between P2 osmometer changes and reservoir water level changes is generally weak,” the word “changes” should be replaced with “fluctuations.”
In analysis of seepage field, In the sentence “The elevation at which maximum displacement occurs is nearly equivalent to the reservoir water level, situated approximately 10 m from upstream dam slope,” the word “situated” should be replaced with “located.”
Double-check for other possible typos.
2. The abstract introduces the problem related to rapid fluctuations in reservoir water level at pumped storage power stations. However, it doesn’t explicitly state the research problem or gap in existing knowledge. A well-defined problem statement would enhance the abstract’s effectiveness.
3. The abstract presents results related to dam deformation, sensitivity to water level changes, and seepage characteristics. However, it doesn’t discuss the implications or practical significance of these findings. Adding a brief section on implications would enhance the abstract. . For instance, how do they impact dam safety or maintenance?
4. The abstract provides equations related to unsaturated soil seepage and stress fields. For example, Darcy’s law is mentioned, but it could be helpful to briefly explain its significance and relevance to unsaturated soil. The boundary conditions and initial conditions for unsteady seepage analysis are outlined.
5. Generally, some sentences can be quite lengthy and may be broken down to improve readability.
6. In the text, refer to figures in their correct form. For example, rewrite “Fig.4” into Figure 4”.
7. You have mentioned a review paper, for a better understanding please cite additional review papers in this field.
8. The paper provides a clear overview of the research topic, but some sentences could be more concise. For example, consider simplifying “exhibits heightened sensitivity” to “is more sensitive.”
Comments on the Quality of English LanguageModerate English editing is needed.
Author Response
Response to Reviewer 1 Comments
Dear reviewer,
We are grateful to you for your time and comprehensive comments on our manuscript. We have implemented your comments and suggestions and wish to submit a revised version of the manuscript for further consideration in Water. Changes in the initial version of the manuscript are highlighted with red font in the revised version. Below, we also provide a point-by-point response to your comments. We look forward to the outcome of your assessment.
Yours sincerely,
On behalf of the co-authors
Xueqin Zheng, Bin Yan, Wei Wang, Kenan Du, and Yixiang Fang*
General comments to author from reviewer #1:
Comment 1: There are some typos in this article. For example:
(1) In abstract, instead of “ both upstream and downstream side” should be “both upstream and downstream sides”
(2) In introduction, instead of “finite element software was employed in this study to analyze changes”. Consider changing it to “finite element software is employed in this study to analyze changes”.
(3) In seepage-stress coupling theory, boasting a maximum height of 50.4 meters”: The word “boasting” may not be the most appropriate choice. Consider using a more neutral term: “with a maximum height of 50.4 meters.”
(4) In seepage-stress coupling theory, “The slope of the upstream side is designed at a ratio of 1:2.0, while the downstream slope follows a ratio of 1:2.5”: Consider rephrasing for clarity: “The upstream slope is designed with a ratio of 1:2.0, and the downstream slope has a ratio of 1:2.5.”
(5) In analysis of seepage field, In the sentence “The correlation between P2 osmometer changes and reservoir water level changes is generally weak,” the word “changes” should be replaced with “fluctuations.”
(6) In analysis of seepage field, In the sentence “The elevation at which maximum displacement occurs is nearly equivalent to the reservoir water level, situated approximately 10 m from upstream dam slope,” the word “situated” should be replaced with “located.”
(7) Double-check for other possible typos.
Reply: According to the suggestions of reviewers, this paper has been improved. The typos have been corrected.
(1) To reduce the length of the abstract, "both upstream and downstream sides" has been removed. (in lines 26-27)
(2) We are very sorry for our negligence of in our manuscript. We have revised typo. (in lines 140-141)
(3) We are very sorry for our negligence of in our manuscript. We have revised typo. (in lines 208)
(4) We are very sorry for our negligence of in our manuscript. We have revised typo. (in lines 209-210)
(5) We are very sorry for our negligence of in our manuscript. We have revised typo. (in lines 294-295)
(6) We are very sorry for our negligence of in our manuscript. We have revised typo. (in lines 401)
(7) We are very sorry for our negligence of in our manuscript. We have revised typo. (in lines 143, 231, 233, 236, 243, 252-253)
Comment 2: The abstract introduces the problem related to rapid fluctuations in reservoir water level at pumped storage power stations. However, it doesn’t explicitly state the research problem or gap in existing knowledge. A well-defined problem statement would enhance the abstract’s effectiveness.
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “Abstract” section (in lines 9-15). Here are the improvements:
The core wall rockfill dams are susceptible to cracking at the dam crest, as well as collapse and settlement of the rockfill during storage and operation periods, particularly due to rapid water level fluctuations in pumped storage power stations. Most studies on the impact of reservoir water level fluctuations on dam deformation consider changes of less than 5m/d, while pumped storage power stations experience much larger fluctuations. Additionally, the seepage and stress fields within the dam's rock and soil interact and influence each other. Few studies have used the coupling theory of seepage and stress to analyze seepage and deformation in core wall rock-fill dams.
Comment 3: The abstract presents results related to dam deformation, sensitivity to water level changes, and seepage characteristics. However, it doesn’t discuss the implications or practical significance of these findings. Adding a brief section on implications would enhance the abstract. . For instance, how do they impact dam safety or maintenance?
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “Abstract” section (in lines 20-25, 32-34). Here are the improvements:
The results indicate that, upon a sudden decrease in reservoir water level, there is a lag in the decline of the wetting line in rockfill I, which creates a large hydraulic gradient, resulting in a reverse seepage field on the dam slope surface and generating a drag force directed upstream. Consequently, significant stress concentration occurs on one-third of the upstream dam slope surface and the seepage curtain, and the horizontal displacement increment is substantially greater than the settlement increment from one-third of the rockfill's height to the dam foundation.
To ensure project safety, it is crucial to control the elevation of the lowest point during a sudden reservoir level drop and to carefully monitor for cracks or voids within approximately one-third of the dam's height in rockfill I and at the dam crest.
Comment 4: The abstract provides equations related to unsaturated soil seepage and stress fields. For example, Darcy’s law is mentioned, but it could be helpful to briefly explain its significance and relevance to unsaturated soil. The boundary conditions and initial conditions for unsteady seepage analysis are outlined.
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “Methodology” section (in lines 148-155). Here are the improvements:
The height of the dam crest exceeds the phreatic line, and it comprises unsaturated soil. Since the deformation of the dam crest area is a critical concern, both saturated and unsaturated seepage flow should be employed to simulate the overall deformation of the dam. Initially, Darcy's law was applied exclusively to the seepage analysis of saturated soil. However, Richards' 1931 study demonstrated that Darcy's law is also applicable to unsaturated soil. The primary distinction is that the permeability coefficient of saturated soil remains constant, whereas that of unsaturated soil varies with changes in water content.
Comment 5: Generally, some sentences can be quite lengthy and may be broken down to improve readability.
Reply: According to the suggestions put forward by the reviewers, this paper has broken up long sentences into multiple sentences. (in lines 46-48, 50-54, 349-351, 376-379, 402-406)
Comment 6: In the text, refer to figures in their correct form. For example, rewrite “Fig.4” into Figure 4”.
Reply: According to the suggestions of reviewers, this paper has been improved. The typos have been corrected. (in lines 269)
Comment 7: You have mentioned a review paper, for a better understanding please cite additional review papers in this field.
Reply: According to the suggestions of reviewers, this paper has been cited additional review papers in this field. (in lines 563-564, 583-586)
Comment 8: The paper provides a clear overview of the research topic, but some sentences could be more concise. For example, consider simplifying “exhibits heightened sensitivity” to “is more sensitive.”
Reply: According to the suggestions of reviewers, this paper has been improved. The typos have been corrected. (in lines 25-26)
Comment 9: Moderate English editing is needed.
Reply: According to the suggestions of reviewers, this paper has been improved the Quality of English Language (See Reply to Comment 1 and 5 above)
We would like to thank you for the careful reading of this manuscript and we hope you can encourage us by your recognition of our work. We completely agree with your comments and have revised the manuscript accordingly. We hope that you will find out our responses to your comments satisfactory.
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe article presents a study of the effect of rapid fluctuations in reservoir water level on the stability of a dam. As part of the study, the authors use a finite element model taking into account the relationship between filtration and stresses; the authors investigated changes in the level of the phreatic line, soil pressure and deformations inside the rock dam (However, they use a model that does not take into account spatial distribution, I will indicate in the note.) The modeling results were compared with monitoring data, examining the effect of rapid changes in reservoir water level on dam deformations. The authors found that sudden drops in reservoir water levels caused the dam to become more sensitive to the minimum water level rather than to the rate at which it was falling. Horizontal displacement of up to 6.5 mm was detected in one third of the rock height, with the largest shrinkage increase of 3.5 mm at the dam crest. The study also indicates a decrease in seepage levels within the rock structure and significant changes in vertical earth pressure, with maximum settlements not exceeding 0.5% of the dam height without the formation of stress zones or crest cracks. The study of the level of filtration is, in our opinion, the strength of this work. The results of this study provide a scientific basis for assessing the condition of the dam and ensuring the long-term safety of the SGSHPP. In my opinion, the study conducted by the authors allows us to pay attention to possible problem areas and investigate the condition of the dam during sharp fluctuations in the water level in the reservoir.
Notes:
1. The introduction section must be supplemented with a literature review on mathematical methods of analysis, grid models, etc.
2. line 111. It is necessary to formulate the purpose of the study.
3. Formula 1. Line 117. Why do you not take into account the Z coordinate. If you introduce restrictions. Then you must indicate this directly. In this case, the model may not fully describe physical processes.
4. Line 161-164. A comma may be missing.
5. Line 179-185. There is a clear seasonality in the data. The question arises: why didn't you consider regression models? I think it would be useful to plot a trend line.
6. Line 339-340. A comma may be missing.
7. Section 7. It is necessary to add a small conclusion and outline ways for further research.
Author Response
Response to Reviewer 2 Comments
Dear reviewer,
We are grateful to you for your time and comprehensive comments on our manuscript. We have implemented your comments and suggestions and wish to submit a revised version of the manuscript for further consideration in Water. Changes in the initial version of the manuscript are highlighted with red font in the revised version. Below, we also provide a point-by-point response to your comments. We look forward to the outcome of your assessment.
Yours sincerely,
On behalf of the co-authors
Xueqin Zheng, Bin Yan, Wei Wang, Kenan Du, and Yixiang Fang*
General comments to author from reviewer #2:
Comment 1: The introduction section must be supplemented with a literature review on mathematical methods of analysis, grid models, etc.
Reply: According to the suggestions of reviewers, this paper has been improved the “Introduction” section. (in lines 68-87, 92-94, 98-100, 107-111)
Comment 2: line 111. It is necessary to formulate the purpose of the study.
Reply: According to the suggestions put forward by the reviewers, this paper has formulated the purpose of the study. (in lines 144-145)
Comment 3: Formula 1. Line 117. Why do you not take into account the Z coordinate. If you introduce restrictions. Then you must indicate this directly. In this case, the model may not fully describe physical processes.
Reply: According to the suggestions put forward by the reviewers, this paper has pointed out the reasons and shortcomings of using two-dimensional models in the “Conclusions and Foresight” section. (in lines 525-527)
Comment 4: Line 161-164. A comma may be missing.
Reply: We checked the paper carefully and did not find a comma missing.
Comment 5: Line 179-185. There is a clear seasonality in the data. The question arises: why didn't you consider regression models? I think it would be useful to plot a trend line.
Reply: Thanks for the reviewer's comment, which is of great guidance for the next research. The water level data from this reservoir was collected over a period of only 40 days, and the sample size is too small to establish a regression model. In the following study, considering the deformation characteristics of core rockfill dams during the multi-year operation period, a regression model should be established.
Comment 6: Line 339-340. A comma may be missing.
Reply: We checked the paper carefully and did not find a comma missing.
Comment 7: Section 7. It is necessary to add a small conclusion and outline ways for further research.
Reply: According to the suggestions of reviewers, this paper has been added Foresight the “Foresight” section. (in lines 521-531)
We would like to thank you for the careful reading of this manuscript and we hope you can encourage us by your recognition of our work. We completely agree with your comments and have revised the manuscript accordingly. We hope that you will find out our responses to your comments satisfactory.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsSUMMARY
The article submitted for review is relevant from the point of view of science and practice. Its theme corresponds to the focus of Water journal.
This paper analyzes the interaction of seepage and deformation of a rockfill dam with a wall core subject to rapid fluctuations in water level in a reservoir. The research problem is that rapid fluctuations in reservoir water level in pumped storage power plants may accelerate collapse, and subsidence of the upper shell inside the main wall rockfill dam may occur. This results in uneven settlement of the riprap and the main wall. As a result, the dam crest will crack and the main wall arch effect will occur.
The authors addressed this problem using finite element modeling using the theory of seepage-deformation coupling. They studied the changes and deformations of the main wall rockfill dam due to rapid fluctuations in the water level of the reservoir.
All simulation results were analyzed together with safety monitoring data. The authors obtained important results that created a scientific basis for assessing the condition of rockfill dams and ensuring the long-term safety of pumped storage power plants.
The reviewer notes the fairly high scientific level of the article and good work in terms of modeling. It is also noted that the article on its topic corresponds to the problems of the Water journal.
However, the reviewer had some comments. They need to be corrected because they will help make this article better. Comments are provided below.
COMMENTS
1. Authors must work with the abstract. At the beginning of the abstract, only an applied problem is given, which talks about the collapse and subsidence of the upper shells inside the rock-fill dam of the main wall and the risks of uneven settlement of the rock fill and the main wall, which can lead to damage to the dam crest. However, the authors must also identify a scientific deficit here. It must be said that there have been few studies in this direction or they are unsystematic in nature, and there is no full-fledged systematic theory about the interaction of seepage and deformation of a rock-fill dam during rapid fluctuations in water levels in reservoirs. This should be added to the beginning of the abstract.
2. Perhaps the formulation of the applied problem at the beginning of the abstract should be shortened. They are overly detailed.
3. The authors also provided an overly detailed description of the results in the abstract. The authors need to shorten them a little and indicate the most important of them at the end of the abstract.
4. Also, the authors indicated only the interpretation of the results. I would like it to be mentioned here exactly what new knowledge and what scientific novelty has been obtained about the interaction of the processes of seepage and deformation in rock-fill plates.
5. The “Introduction” section is written very modestly; it needs to be expanded by conducting a more detailed analysis of the current state of the issue. It is somewhat confusing that the authors, for example, on line 40 provide five literary references at once, and on line 43 eight literary references at once. However, they do not disclose the content of each of these links and it is not clear how they differ from each other. The literature analysis should be more comprehensive. It is necessary to group literary sources according to various criteria. For example, studying the processes of interconnection, seepage and deformation of platinum, as well as ways to solve such problems from the point of view of applied engineering problems.
6. At the end of the introduction section, authors must clearly outline the scientific problem, goal and tasks of the study.
7. Section 2 with the title “Seepage-Stress Coupling Theory” is also more of a literary reference nature. The authors should probably rename this section “Methodology” since this is the theory behind the research.
8. It is also recommended to expand it, because the authors must justify the choice of basic objects for their research.
9. In general, dividing the article into 7 paragraphs does not seem very logical. The authors are encouraged to adopt the more typical IMRAD study design. In the “Introduction” section, you need to present a literature review and background on the issue under consideration, as well as formulate the goal and tasks of the research. In the methodological section, you must indicate all the theoretical and applied aspects on which the study was based, and your own results should be included in the Results section.
10. The authors provided a lot of graphic material, but the results were poorly discussed. It is necessary to put the “Discussion” section into a separate paragraph. There you need to compare your results with the results obtained previously by other authors. The scientific novelty of the authors is not yet very clear. The applied engineering significance of the article’s results is very high. Authors are recommended to more clearly formulate scientific novelty and differences from previous studies.
11. The list of references, including 29 titles, is very small for research of this level. It is recommended to increase it to 40-45 items.
After making corrections, the reviewer would like to take another look at the article to see how much it has improved in terms of methodology and presentation of results. The general conclusion is Major Revisions.
Comments for author File: Comments.pdf
English language needs some minor changes.
Author Response
Response to Reviewer 3 Comments
Dear reviewer,
We are grateful to you for your time and comprehensive comments on our manuscript. We have implemented your comments and suggestions and wish to submit a revised version of the manuscript for further consideration in Water. Changes in the initial version of the manuscript are highlighted with red font in the revised version. Below, we also provide a point-by-point response to your comments. We look forward to the outcome of your assessment.
Yours sincerely,
On behalf of the co-authors
Xueqin Zheng, Bin Yan, Wei Wang, Kenan Du, and Yixiang Fang*
General comments to author from reviewer #3:
Comment 1: Authors must work with the abstract. At the beginning of the abstract, only an applied problem is given, which talks about the collapse and subsidence of the upper shells inside the rock-fill dam of the main wall and the risks of uneven settlement of the rock fill and the main wall, which can lead to damage to the dam crest. However, the authors must also identify a scientific deficit here. It must be said that there have been few studies in this direction or they are unsystematic in nature, and there is no full-fledged systematic theory about the interaction of seepage and deformation of a rock-fill dam during rapid fluctuations in water levels in reservoirs. This should be added to the beginning of the abstract.
Reply: According to the suggestions of reviewers, this paper has been improved. The scientific deficits have been identified (in lines 11-15). Here are the improvements:
Most studies on the impact of reservoir water level fluctuations on dam deformation consider fluctuations of less than 5m/d, while pumped storage power stations experience much larger fluctuations. Additionally, the seepage and stress fields within the dam's rock and soil interact and influence each other. Few studies have used the coupling theory of seepage and stress to analyze seepage and deformation in core wall rockfill dams.
Comment 2: Perhaps the formulation of the applied problem at the beginning of the abstract should be shortened. They are overly detailed.
Reply: According to the suggestions put forward by the reviewers, this paper has shortened the “Abstract” section (in lines 9-11). Here are the improvements:
The core wall rockfill dams are susceptible to cracking at the dam crest, as well as collapse and settlement of the rockfill during storage and operation periods, particularly due to rapid water level fluctuations in pumped storage power stations.
Comment 3: The authors also provided an overly detailed description of the results in the abstract. The authors need to shorten them a little and indicate the most important of them at the end of the abstract.
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “Abstract” section (in lines 25-27, 32-34). Here are the improvements:
Delete “core wall rockfill dam” (in lines 25-26)
Delete “both upstream and downstream side” (in lines 26-27)
Delete “the seepage line within the core wall has experienced a significant reduction, by approximately 87%.”
Delete “The overall maximum settlement of the core wall and rockfill is under 0.5% of the dam height, without any observed tensile stress zones or cracks at the dam crest.”
Add “To ensure project safety, it is crucial to control the elevation of the lowest point during a sudden reservoir level drop and to carefully monitor for cracks or voids within approximately one-third of the dam's height in rockfill I and at the dam crest.” (in lines 32-34)
Comment 4: Also, the authors indicated only the interpretation of the results. I would like it to be mentioned here exactly what new knowledge and what scientific novelty has been obtained about the interaction of the processes of seepage and deformation in rock-fill plates.
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “Abstract” section (in lines 20-26). Here are the improvements:
The results indicate that, upon a sudden decrease in reservoir water level, there is a lag in the decline of the phreatic line in rockfill I, which creates a large hydraulic gradient, resulting in a reverse seepage field on the dam slope surface and generating a drag force directed upstream. Consequently, significant stress concentration occurs on one-third of the upstream dam slope surface and the seepage curtain, and the horizontal displacement increment is substantially greater than the settlement increment from one-third of the rockfill's height to the dam foundation. The deformation is more sensitive to the lowest reservoir water level rather than to the fastest rate of decline.
Comment 5: The “Introduction” section is written very modestly; it needs to be expanded by conducting a more detailed analysis of the current state of the issue. It is somewhat confusing that the authors, for example, on line 40 provide five literary references at once, and on line 43 eight literary references at once. However, they do not disclose the content of each of these links and it is not clear how they differ from each other. The literature analysis should be more comprehensive. It is necessary to group literary sources according to various criteria. For example, studying the processes of interconnection, seepage and deformation of platinum, as well as ways to solve such problems from the point of view of applied engineering problems.
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “Introduction” section (in lines 44-46, 68-87, 92-94, 98-100, 107-111).
Comment 6: At the end of the introduction section, authors must clearly outline the scientific problem, goal and tasks of the study.
Reply: According to the suggestions of reviewers, this paper has been improved. (in lines 144-145)
Comment 7: Section 2 with the title “Seepage-Stress Coupling Theory” is also more of a literary reference nature. The authors should probably rename this section “Methodology” since this is the theory behind the research.
Reply: According to the suggestions of reviewers, this paper has been improved. (in lines 146)
Comment 8: It is also recommended to expand it, because the authors must justify the choice of basic objects for their research.
Reply: According to the suggestions of reviewers, this paper has been improved the “Methodology” section. (in lines 148-155, 166-169, 172-196)
Comment 9: In general, dividing the article into 7 paragraphs does not seem very logical. The authors are encouraged to adopt the more typical IMRAD study design. In the “Introduction” section, you need to present a literature review and background on the issue under consideration, as well as formulate the goal and tasks of the research. In the methodological section, you must indicate all the theoretical and applied aspects on which the study was based, and your own results should be included in the Results section.
Reply: According to the suggestions of reviewers, this paper has been improved. The revised article is divided into five chapters, including Introduction, Methodology, Numerical Model of a CWRD, Numerical Simulation Results and Monitoring Data Analysis, and Conclusions and Foresight. (in lines 40, 146, 197, 254, 484)
Comment 10: The authors provided a lot of graphic material, but the results were poorly discussed. It is necessary to put the “Discussion” section into a separate paragraph. There you need to compare your results with the results obtained previously by other authors. The scientific novelty of the authors is not yet very clear. The applied engineering significance of the article’s results is very high. Authors are recommended to more clearly formulate scientific novelty and differences from previous studies.
Reply: According to the suggestions of reviewers, this paper has been improved. Combine the analysis section into a single paragraph(in lines 349-362, 393-406, 469-474), enriching the content (in lines 259-562, 289-292, 299-302, 313-334, 351-356, 373-379, 415-420, 444-447) and presenting an innovative conclusion different from previous research (in lines 491-498, 512-516).
Comment 11: The list of references, including 29 titles, is very small for research of this level. It is recommended to increase it to 40-45 items.
Reply: According to the suggestions put forward by the reviewers, this paper has improved the “References” section, increased references to 41 articles. (in lines 549-551, 557-564, 571-573, 577-578, 583-586, 592-594, 601-605, 610-611, 617-618, 623-625).
Comment 12: English language needs some minor changes.
Reply: According to the suggestions of reviewers, this paper has been improved the Quality of English Language. (in lines 26-27, 140-141, 143, 208, 209-210, 231, 233, 236, 243, 252-253, 294-295, 401)
We would like to thank you for the careful reading of this manuscript and we hope you can encourage us by your recognition of our work. We completely agree with your comments and have revised the manuscript accordingly. We hope that you will find out our responses to your comments satisfactory.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors modified the manuscript based on the reviewer's comments. The manuscript could be published in the present format.
Reviewer 3 Report
Comments and Suggestions for AuthorsThe authors took into account all the reviewer’s comments and, thereby, significantly improved the manuscript. In its current form, the article is suitable for publication.