Analysis of Mine Change Using 3D Spatial Information Based on Drone Image

Round 1

Reviewer 1 Report

General comments:

The manuscript, entitled " Analysis of Mine Change Using 3D Spatial Information Based on Drone Image " focuses on the possibility of using drone photogrammetry for determining the changes and recovery in mines. There are some issues with this manuscript, mainly related to the readability and composition of the manuscript.

 Please review the quality of your English throughout the manuscript.

I would like to see some concluding remarks and recommendation in the abstract section.

Specific comments:

Point 1: I recommend to the authors in the theory part to add more literature review in order to emphasize the need and originality of your research.

Point 2: Line 44 to Line 51. The traditional…results. (Write the source).

Point 3: Line 52 to Line 54. Accidents…photogrammetry. (Write the source).

Point 4: Line 56 to Line 59. Produced…analysis. (Write the source).

Point 5: Line 84 to Line 89. UAVs…data. (Write the source).

Point 6: Line 90 to Line 96. The…Meta shape. (Write the source).

Point 7: Line 97. Figure 1 move to the method section or delete the figure.

Point 8: Line 133: 3. Data Acquisition and processing in my opinion this is the method section and write in title Method and Materials.

Point 9: Line 152 to Line 153 Figure 4. Is the study area map and incorporate all map elements.

Point 10: Line 262 to Line 263 Figure 11; please make visible to the readers.

Point 11: Discussion section (Line 313), this is an important part of the study and I suggest to the authors compare your results with other similar studies in order to emphasize the originality and novelty of the study.

Point 12: Line 416. I suggest write some recommendations to the concerned policy makers and implementers.

Point 13: Line 429: References: The authors used only 21 citations (references) it is so small for the article and please add more citations in the theory and discussion section.

 

Author Response

Reviewer(s)' Comments to Author:

The manuscript, entitled " Analysis of Mine Change Using 3D Spatial Information Based on Drone Image " focuses on the possibility of using drone photogrammetry for determining the changes and recovery in mines. There are some issues with this manuscript, mainly related to the readability and composition of the manuscript.

 

Please review the quality of your English throughout the manuscript.

 

I would like to see some concluding remarks and recommendation in the abstract section.

 

Specific comments:

 

Point 1: I recommend to the authors in the theory part to add more literature review in order to emphasize the need and originality of your research.

 

Point 2: Line 44 to Line 51. The traditional…results. (Write the source).

 

Point 3: Line 52 to Line 54. Accidents…photogrammetry. (Write the source).

 

Point 4: Line 56 to Line 59. Produced…analysis. (Write the source).

 

Point 5: Line 84 to Line 89. UAVs…data. (Write the source).

 

Point 6: Line 90 to Line 96. The…Meta shape. (Write the source).

 

Point 7: Line 97. Figure 1 move to the method section or delete the figure.

 

Point 8: Line 133: 3. Data Acquisition and processing in my opinion this is the method section and write in title Method and Materials.

 

Point 9: Line 152 to Line 153 Figure 4. Is the study area map and incorporate all map elements.

 

Point 10: Line 262 to Line 263 Figure 11; please make visible to the readers.

 

Point 11: Discussion section (Line 313), this is an important part of the study and I suggest to the authors compare your results with other similar studies in order to emphasize the originality and novelty of the study.

 

Point 12: Line 416. I suggest write some recommendations to the concerned policy makers and implementers.

 

Point 13: Line 429: References: The authors used only 21 citations (references) it is so small for the article and please add more citations in the theory and discussion section.

 

Response:

Thank you for your attentive review of our manuscript. We have revised the manuscript based on your suggestions. Our response to each point is presented below.

 

1. More references have been added to emphasize the need and originality of our research.

2, 5-6. We have added the related references.

3-4. As a result of the review of English language quality, the content was not delivered correctly. Therefore, we have corrected the content and added related references.

7. The content describes the general UAV image processing process, and the research flow chart of this study is shown in Figure 3.
8. We found your suggestion to be more appropriate, and modified the title to Method and materials.
9. We have modified the map by adding details such as azimuth and scale.
10. We have enlarged the picture to improve the clarity.
11. We believe that the methods and differences in existing studies are described well, and that the limitations of our study are described well.
12. Following the content in Line 414, we have clarified that the results of this study can serve sufficiently as basic data that can help formulate methods and standards for using drones in mines.
13. As per your suggestion, more references have been added along with corrections to the details above.

 

Reviewer 2 Report

1. It is suggested that the title "... Drone Image" be revised to "... Drone Orthoimage" to better consistent with the actual work.
2. In Introduction section, the authors should highlight the innovation of this work based on strengthening the literature analysis. For example, why use drone orthoimage instead of the oblique photography or Lidar point cloud method?
3. The last two lines of Table 1 are wrong and should be reversed.
4. In section 3.3, line 184-185, the expression of overlaps in confusing. If the site elevation difference is large, the plane overlap of different positions at the same flight altitude is different.
5. Where are the position of sections 1-5 shown in the figure 11 on the plane, respectively?
6. If the mining output induced elevation reduction, why did the elevation add because some position are higher comparing the the second line to the first line shown section 1-5 in figure 11?

Author Response

Reviewer(s)' Comments to Author:

1. It is suggested that the title "... Drone Image" be revised to "... Drone Orthoimage" to better consistent with the actual work.

 

2. In Introduction section, the authors should highlight the innovation of this work based on strengthening the literature analysis. For example, why use drone orthoimage instead of the oblique photography or Lidar point cloud method?

 

3. The last two lines of Table 1 are wrong and should be reversed.

 

4. In section 3.3, line 184-185, the expression of overlaps in confusing. If the site elevation difference is large, the plane overlap of different positions at the same flight altitude is different.

 

5. Where are the position of sections 1-5 shown in the figure 11 on the plane, respectively?

 

6. If the mining output induced elevation reduction, why did the elevation add because some position are higher comparing the the second line to the first line shown section 1-5 in figure 11?

 

Reply:

Thank you for your in-depth review of our manuscript. Our responses to your questions are presented below.

 

1. This study aims to analyze the 3D spatial information acquired by drone images and the parts that can be used for mine management of drone images. We intend to shoot a vertical image, but we believe a drone image is more suitable because it is difficult for an actual captured image to become a precise vertical image because of the nature of the drone.
2. Although the use of drone lidar has been increasing recently, it is still difficult to access in terms of cost and usability, compared with existing drone videography. In addition, in the case of the site considered in this study, because not many parts are available to cover the sides, the image was processed using vertical photos, which are the most basic images used in drone photogrammetry. In the case of oblique photos, they can be used and analyzed for follow-up studies.
3. Thank you for pointing out the mistake. The table contents have been corrected accordingly.
4. There was an error in the expression for end overlap and side lap, which has now been corrected.
5. It is shown in Figure 9, and the corresponding part is shown for the right part in Figure 9 where mining is being conducted.
6. Thank you for the detailed review. The authors also felt strange about this part at the time of data analysis and confirmed it. There is a part where the altitude reduced due to blasting in the mine, and it was confirmed through enquiry with the mine site manager that this phenomenon can be discovered because the ground must be cleared for safety and maintenance of the planned height.

Reviewer 3 Report

Thank you for the opportunity to review the article for publication in the Sustainability journal. I would like to emphasize that the subject matter of the article is very topical. The use of unmanned aerial vehicles in low altitude photogrammetry is gaining more and more popularity. It's also because dedicated software keeps getting better. The article was written correctly. The authors showed great knowledge and practical experience. It deserves praise to show relatively large errors generated by this method (compared to classic methods). Despite the indicated precision limitations, the authors correctly indicated the advantages of this method. I believe that the article is written correctly and is suitable for publication in its current form. It is interesting and meets the requirements of the journal. In the future, it's worth taking an interest in UAVs positioned precisely on the basis of GNSS-RTK corrections - more and more popular nowadays. The technology eliminates or significantly reduces the need for control points. The second issue is the assessment (in such repeatable conditions) of the dispersion of the measurement errors by measuring the same area several times. 

Author Response

Reviewer(s)' Comments to Author:

Thank you for the opportunity to review the article for publication in the Sustainability journal. I would like to emphasize that the subject matter of the article is very topical. The use of unmanned aerial vehicles in low altitude photogrammetry is gaining more and more popularity. It's also because dedicated software keeps getting better. The article was written correctly. The authors showed great knowledge and practical experience. It deserves praise to show relatively large errors generated by this method (compared to classic methods). Despite the indicated precision limitations, the authors correctly indicated the advantages of this method. I believe that the article is written correctly and is suitable for publication in its current form. It is interesting and meets the requirements of the journal. In the future, it's worth taking an interest in UAVs positioned precisely on the basis of GNSS-RTK corrections - more and more popular nowadays. The technology eliminates or significantly reduces the need for control points. The second issue is the assessment (in such repeatable conditions) of the dispersion of the measurement errors by measuring the same area several times.

 

Response:

Thank you for your detailed review. This study aims to evaluate the utility of drones in mines. As suggested by the reviewer, we agree that iterative analysis is necessary to realize higher reliability and analysis using a UAV equipped with GNSS-RTK in a future study.

Thank you for the beneficial comments. In the future, we plan to evaluate the usefulness of drone lidar and terrestrial scanner, whose utility has recently been increasing, in addition to continuous and repeated research. Thank you for your sincere advice and interest in my research findings.

Round 2

Reviewer 1 Report

Thank you for the revisions you made to the manuscript! You met my comments really well, and I think it is now ready to be published.

Author Response

Response to the Reviewer’s Comments

Reviewer #1_Round 2

 

Reviewer(s)' Comments to Author:

Thank you for the revisions you made to the manuscript! You met my comments really well, and I think it is now ready to be published.

 

Reply:

We thank the reviewer for a meticulous assessment of our manuscript. We are grateful for the insightful comments and appreciation.

Reviewer 2 Report

For the authors' responses to the review comments of the first round:

1. The ortho image method was used in this work shown in Figure 1.

2. The introduction section should give the description of choosing the study method used in this work.

3. Addressed.

4. Addressed.

5. The specific positions of sections 1-5 should be clearly marked in Figure 9.

6. This phenomenon can be explained in context.

Author Response

Response to the Reviewer’s Comments

Reviewer #2_Round 2

 

Reviewer(s)' Comments to Author:

For the authors' responses to the review comments of the first round:

1. The ortho image method was used in this work shown in Figure 1.
2. The introduction section should give the description of choosing the study method used in this work.
3. Addressed.
4. Addressed.
5. The specific positions of sections 1-5 should be clearly marked in Figure 9.
6. This phenomenon can be explained in context.

 

Reply:

We thank the reviewer for a meticulous assessment of our manuscript. We are highly grateful for these pertinent comments and suggestions. Our response to these comments is given below:

1. Your comment is correct that the ortho image is used in Figure 1. However, this part contains information about the image processing process and output. In addition, orthographic images were used to analyze the accuracy of check points and to calculate the quantity (earth work volume); however, the original images taken with a drone were also used to determine whether or not to restore the mountainous area. Therefore, it seems appropriate to use the term “drone image”, which is essential to any analysis.
2. We thank the reviewer for this pertinent suggestion. We believe that the reasons for selecting the mine change analysis method using drone photogrammetry are explained in Lines 44~52, 71~79.
3. Thank you.
4. Thank you.
5. There was an error in the process of editing some files. We have rectified it in now and specific positions of Sections 1–5 are clearly marked in Figure 9, as per your suggestion.
6. We thank the reviewer for this pertinent suggestion. The required explanation is given at line 275 of the text.