Measurement and Analysis of the Influence Factors of Tractor Tire Contact Area Based on a Multiple Linear Regression Equation

Round 1

Reviewer 1 Report

This is an article about interactions between tire and soil in conditions simulated at laboratory. Authors intention was finding regression functions which describe contact area. The independent variables were: pressure, load and speed. It should be mentioned that driving with significantly reduced tire pressure causes faster tire wear and in extreme cases can damage it suddenly.

 

The advantage of tests presented in the paper is high similarity of the testing way to move of driving wheel on soil. However the whole stand is not shown but only tire in Figure 2. But I coudn't fined information about number of probes and prepering of soil between tests.

The accuracy of soil profile measuring was given but what is the relative error of these calculations which arise from accuracy of measuring speed, load and pressure?

Many publications may be found from similar range like the paper, for instance

DOI:10.1201/b12729

10.3390/s19092116

10.1007/s12239-021-0071-x

10.21307/tp-2021-015

10.22616/ERDev.2020.19.TF351

 

in general please add more newver references - read comments at the bottom also.

The fact that carring the same loads at reduced inflation pressure leading to increases fuel consumption and reduces soil compaction as well is commonly known. Other conclusions may be and should be also discussed with references.

Why in 3rd sections there is noone citation?

 

Please, add detailed informations about the tire (photo with tire code), tube-type/less, nominal loading, plies, depth of tread, max speed, previously used or new etc. Put it in paragraph text instead of index below table 2.

Where the tire is used in agricultural machines, in contact with this particular type of soil?

And is it possible to control the load and the speed in this cases of the tire applications?

 

Use uniform titles of figures. Join figures 1 and 2 and point out the same visible instruments (items) of the equipment.

 

Are tables properly formatted? Put attention to position, width of table, units, distances, bold chars etc.

 

Add explanation why the types of tire, soil, values of pressure, load, speed

 

It is not clear from author contribution list who of authors made test, calculations etc.

 

Your "Roentgen Formula" is rather known as Heron's (from ancient Alexandria) formula. Similar one was published in medieval China.

 

Add list of symbols and its definitions at apropriate place. Next respect this convention

In equation (2) A not s is calculated, as area should be coded by A symbol.

In eq. (4) as well.

Next small s is area and speed in some places.

Symbol p is used for pressure and a half of perimeter.

 

line

 

6-9: domain 163.com looks unprofessional

 

36: lack of space

 

52: in Grec^venko should be \v{c}. In list of references (line 356) also.

 

Table 1. Correct three right columns. There is lack of sth

 

93: unneccessary ", a"

 

Figure 3. everything is mixed in the title

 

153: fractal theory is not developed by authors. Please check equations and add apropriate references

 

160: why p0=p1

 

162: what is M?

 

164: should be {(xn,yn):n=1,2...,N} where for N and numbers use normalfonts because of constant values

 

190: ++

 

195: mean S should be italic

 

258: 90.8% of determination is not as high as it seems in the system of 3 degrees of freedom. It means over 9 % of determination by an unmeasured parameters. What the parameters may be?

 

Figures 10 and 11 - what unit is on vertical axis? What symbols?

 

Figure 11. add distance between axis title and numerical values

 

313: larger

 

340: Cercet\v{a}ri Agronomice \^{\i}n Moldova 

 

369: Cueto, O.G., Coronel, C.E.I., Bravo, E.L., Morfa, C.A.R., Suárez, M.H.

 

 

References

please add doi

pos. 3, 5, 8, 11, 13, 19,  et al.

 

Taghavifar, H. is 4 times cited

Mardani, A. 3 times

Arvidsson, J. 2 times

Keller, T. 3 times

Schjønning, P. 3 times

Lamandé, M. 2 times

Upadhyaya, S. K. 3 times

Diserens, E. 2 times

 

 

Journals:

Soil Till. Res. is 5 times cited

Measurement - 2 times

Biosyst. Eng. - 2 times

J. Terramech - 5 times

 

A short list of references there was used here, so in my opinion there is no reason to cite a given author or journal more than once

In my opinion English is quite good, but some terms are strange

Author Response

Response to Reviewer 1 Comments

Point 1: The advantage of tests presented in the paper is high similarity of the testing way to move of driving wheel on soil. However the whole stand is not shown but only tire in Figure 2. But I coudn't fined information about number of probes and prepering of soil between tests.

Response 1: The principle of the laser profiler is measure the vertical distance between the standard and ground surface based on the triangulation technique. All these vertical distances formed the roughness curve of the ground surface. We annotated the name of structures in Figure 4, which shown the test site.

Point 2: The accuracy of soil profile measuring was given but what is the relative error of these calculations which arise from accuracy of measuring speed, load and pressure?

Response 2: The tractor moved forward under a particular combination of speed,  tire load and inflation pressure, and it was stopped when the tire footprint formed. Then, the laser profiler was put on the right above of the footprint and measured the distance between the standard and ground. All the footprint was measured under static state. So, we think the error of these these calculations which arise from accuracy of measuring speed, load and pressure is negligible.

Point 3: references

1、Many publications may be found from similar range like the paper, for instance

DOI:10.1201/b12729

10.3390/s19092116

10.1007/s12239-021-0071-x

10.21307/tp-2021-015

10.22616/ERDev.2020.19.TF351

2、please add doi

pos. 3, 5, 8, 11, 13, 19,  et al.

 Taghavifar, H. is 4 times cited

Mardani, A. 3 times

Arvidsson, J. 2 times

Keller, T. 3 times

Schjønning, P. 3 times

Lamandé, M. 2 times

Upadhyaya, S. K. 3 times

Diserens, E. 2 times

3、Soil Till. Res. is 5 times cited

Measurement - 2 times

Biosyst. Eng. - 2 times

1. Terramech - 5 times

 A short list of references there was used here, so in my opinion there is no reason to cite a given author or journal more than once

in general please add more newver references - read comments at the bottom also.

Response 3: We updated 10 new references and ensured that one author cited one time. But, Soil till.Res, Measurement, Biosyst. Eng, and J. Terramech are the mainstream and relatively authoritative magazine in these area, despite our best efforts, we cannot cite a journal no more than once. In addition, we added the doi for every references. Please see references section. Thanks

Point 4: The fact that carring the same loads at reduced inflation pressure leading to increases fuel consumption and reduces soil compaction as well is commonly known. Other conclusions may be and should be also discussed with references.

Response 4: OK, we updated several references to discussed in the paper. Thanks

Point 5: Why in 3rd sections there is no one citation?

Response 5: We added several references in 3^rd section. Please see lines 268, 293, and 303.

Point 6: Please, add detailed informations about the tire (photo with tire code), tube-type/less, nominal loading, plies, depth of tread, max speed, previously used or new etc. Put it in paragraph text instead of index below table 2.

Response 6: We added this information in lines 103-108. Thanks

Point 7: Where the tire is used in agricultural machines, in contact with this particular type of soil?And is it possible to control the load and the speed in this cases of the tire applications?

Response 7: In China, a 6.00-14 bias-ply tire often used as the tractor front wheels under 50 horsepower. We think it is possible to control the load and the speed in this cases of the tire applications. The speed depended on the power of the tractor and the various resistance, we can adjust the speed by shifting gears. While the load depended on the dead weight of the tractor and the loaded weight, and we can adjust the load by increasing or decreasing the loaded weight.  

Point 8:Use uniform titles of figures. Join figures 1 and 2 and point out the same visible instruments (items) of the equipment.

Response 8: In figure 2, we just want to show the tire used in the experiment, while the figure 1 shows the structures of the soil-bin testing facility. After the discussion, we think we don’t need to uniform these two figures. Thanks

Point 9: Are tables properly formatted? Put attention to position, width of table, units, distances, bold chars etc.

Response 9: OK. Thanks

Point 10: Add explanation why the types of tire, soil, values of pressure, load, speed

Response 10: We added this information in lines 103-114. Thanks

Point 11: It is not clear from author contribution list who of authors made test, calculations etc.

Response 11: We updated relevant information in author contributions, please see lines 328-329.

Point 12: Your "Roentgen Formula" is rather known as Heron's (from ancient Alexandria) formula. Similar one was published in medieval China.

Response 12: By looking further into the information, we found that the Roentgen formula is one of the applications of the Heron’s Theorem, which used to calculate the area of the triangle formed by any three points if you know the length of three sides.

Point 13:Add list of symbols and its definitions at apropriate place. Next respect this convention.

Response 13: We checked the symbols again, and gave every symbols a definition in their respective positions.

 Point 14: In equation (2) A not s is calculated, as area should be coded by A symbol.

In eq. (4) as well.Next small s is area and speed in some places. Symbol p is used for pressure and a half of perimeter.

Response 14: We unified the properties of the letters and the corresponding modifications were made in the paper. Where A is used for area, small s is used for speed, and p is used for pressure.  Please see lines 185-190. Thanks.

 Point 15:6-9: domain 163.com looks unprofessional.

 Response 15: We have updated the professional emails in line 6-9. Thanks.

 Point 16:36: lack of space

 Response 16: Ok. Thanks

 Point 17:52: in Grec^venko should be \v{c}. In list of references (line 356) also.

 Response 17: Ok. Thanks

 Point 18:Table 1. Correct three right columns. There is lack of sth

 Response 18: OK. Thanks

 Point 19:93: unneccessary ", a"

 Response 19: Ok. Thanks

 Point 20:Figure 3. everything is mixed in the title

 Response 20: We adjusted it in paper. Please see line 135-138. Thanks

 Point 21:153: fractal theory is not developed by authors. Please check equations and add apropriate references

 Response 21: We added the reference in paper. Thanks

 Point 22:160: why p0=p1

 Response 22: Here p₀ is initial point, and the the first point of iteration depends on p₀ and any set of affine functions. The initial point can choose random, which means every point can be as the initial point, so p₀=p_i. In this paper, we choose p₁ as the initial point.

 Point 23:162: what is M?

 Response 23: F_N,M (N=2, 3, ..., N, M=1, 2, ..., M) is the test point, we updated this information in the paper, please lines 166-167. Thanks

 Point 24:164: should be {(xn,yn):n=1,2...,N} where for N and numbers use normalfonts because of constant values

 Response 24: OK. Thanks

 Point 25:190: ++

 Response 25: OK.Thanks

 Point 26:195: mean S should be italic

 Response 26: OK. Thanks

 Point 27:258: 90.8% of determination is not as high as it seems in the system of 3 degrees of freedom. It means over 9 % of determination by an unmeasured parameters. What the parameters may be?

 Response 27: Such as the soil and tire characteristic parameter.  

 Point 28:Figures 10 and 11 - what unit is on vertical axis? What symbols?

 Response 28: It is mm², the unit of the contact area in the experiment. 

 Point 29:Figure 11. add distance between axis title and numerical values

  Response 29: OK. Thanks

 Point 30:313: larger

 Response 30: OK. Thanks

 Point 31:340: Cercet\v{a}ri Agronomice \^{\i}n Moldova 

 Response 31: OK. Thanks

Point 32:369: Cueto, O.G., Coronel, C.E.I., Bravo, E.L., Morfa, C.A.R., Suárez, M.H.

 Response 32: OK.Thanks

Reviewer 2 Report

The article contains a number of reactionary errors, which are highlighted in the text. These include missing spaces between the text and the backs of subsequent subsections, tables or figures. Missing spaces in the text, misplaced punctuation marks.

Some comments are given below.

 

The title should be reworded so that it is written with stylistic abduction.

Explanations of abbreviations used should be given when the abbreviation is first placed in the text and not for subsequent citation.

Line 83 Please still give the brevity value of this soil.

Fig. 1 should be enlarged to make it more readable.

Lines 108 and 109 Please explain the choice of tyre pressure values chosen for the tests.

Fig. 4 Please add an explanation of the elements of the test bench shown in the photo.

Line 315 Please provide the numbers of the equations that support this conclusion.

The article cannot be published as the involvement of all co-authors is not stated. No information is available on the extent of the work of the Korean co-authors.

Comments for author File: Comments.pdf

The authors should improve some entries in terms of language.

It would be advisable to have the text checked by a native speaker familiar with the relevant technical vocabulary.

Author Response

Response to Reviewer 2 Comments

 

Point 1: The article contains a number of reactionary errors, which are highlighted in the text. These include missing spaces between the text and the backs of subsequent subsections, tables or figures. Missing spaces in the text, misplaced punctuation marks.

Response 1: Thank you very much for your patient revision of this paper. The modifications you made directly in PDF have been modified in sequence according to your suggestions, we did not response these changes one by one below. Thanks

Point 2: The title should be reworded so that it is written with stylistic abduction.

Response 2: In this study, a signal tire soil-bin and a laser roughness instrument were used to (1) measure the contact area between the soil and tire under different combinations of the speed, tire load, and inflation pressure; (2) develop empirical relationships between the contact area and the speed, tire load, and inflation pressure; (3) analyze the effect of the speed, tire load, and the inflation pressure on contact area to contribute to understanding of compaction processes based on the equation we developed. So we changed the word “Analyse” to “Measurement and analysis” to described the paper better.

Point 3: Explanations of abbreviations used should be given when the abbreviation is first placed in the text and not for subsequent citation.

Response 3: OK. Thanks

Point 4: Line 83 Please still give the brevity value of this soil.

Response 4: We added the mean soil compactness in the Table 1. Thanks

Point 5: Fig. 1 should be enlarged to make it more readable.

Response 5: OK. Thanks

Point 6: Lines 108 and 109 Please explain the choice of tyre pressure values chosen for the tests.

Response 6: For the 6.00-14 bias tire (four-ply rating), the recommended inflation pressure of 180 kPa corresponds to the maximum capacity of 3.70 kN (China, 2017). 

In order to investigate the various of the contact area under different values of inflation pressure (overinflated, slightly underinflated, and seriously underinflated), 30 psi (207 kPa, overinflated), 20 psi (138 kPa, slightly underinflated), and 10 psi (69 kPa, seriously underinflated) of the tire pressure were selected in this paper. Please see Table 2 and lines 103-114. Thanks

Point 7: Fig. 4 Please add an explanation of the elements of the test bench shown in the photo.

Response 7: OK. Thanks.

Point 8: Line 315 Please provide the numbers of the equations that support this conclusion.

Response 8: OK. Thanks

Point 9: The article cannot be published as the involvement of all co-authors is not stated. No information is available on the extent of the work of the Korean co-authors.

Response 9: I copied the content from another paper i am working on. I updated in the system and forgot to modified in the paper when I submitted it. So sorry for that, and I modified in the paper this time. Please see lines 328-329. Thanks

 

Reviewer 3 Report

This paper proposed a method to measure the 3D contact area of a pneumatic tire by a laser profiler on a signal tire soil-bin testing facility, and analyzed the effect of different influencing factors on tire contact area. The study lacks innovation and the content is relatively thin, lacking sufficient theoretical analysis and experimental results analysis. In addition, there are some other problems.

1. In Abstract, the description in lines 19-21 does not match the study results.

2. In Abstract, the description of the part “(3) the contact area at the soil-tire…when inflation pressure was fixed.” is ambiguous.

3. In lines 32 and 33, it is necessary to explain the environmental impact of the emissions of these gases.

4. In lines 39-48, this paragraph describes some testing methods and does not compare the advantages and disadvantages, in addition to not linking to the research methods of this study, so what is the purpose of this description?

5. In lines 54-56, the two references cited are from the same journal, literature 15 was published earlier than literature 14, and literature 14 shows that the effect of inflation pressure on contact area is negligible, then according to the latest study is it possible to assume that the effect of inflation pressure is negligible, while the results of your study show that there is a certain effect of inflation pressure. Therefore, the description here needs to be revised.

6. In line 108, what is the basis for the selection of the inflation pressure values? In practical applications, the impact on the tire area should be reduced while ensuring normal tire operating conditions. Therefore the study of lower pressure values is meaningful for practical production applications.

7. In lines 179-182, the variables in the formulas should be explained in the text.

8. In line 188, ‘s’ should be capitalized.

9. The before interpolation and after interpolation curves have been compared in 3.2 Fractal dimension, so what is the role of Figure 7?

10. The coefficients in equation 11 do not correspond to the data in Table 4.

11. There is an error in the vertical coordinate unit of Figure 10(a).

12. There is an error in the name of the horizontal coordinate of Figure 10(b)

 

13. In lines 319-320, this part is not consistent with the results of the above study.

Moderate editing of English language

Author Response

Response to Reviewer 3 Comments

Point 1: In Abstract, the description in lines 19-21 does not match the study results.

Response 1: We modified it in the paper, please see lines 19-21 . Thanks

Point 2: In Abstract, the description of the part “(3) the contact area at the soil-tire…when inflation pressure was fixed.” is ambiguous.

Response 2: We redescribed this sentence, please see lines 21-24. Thanks

Point 3: In lines 32 and 33, it is necessary to explain the environmental impact of the emissions of these gases.

Response 3: We added the explanation in lines 34-35. Thanks

Point 4: In lines 39-48, this paragraph describes some testing methods and does not compare the advantages and disadvantages, in addition to not linking to the research methods of this study, so what is the purpose of this description?

Response 4: After the discussion, we decided to delete the paragraph. Thanks

Point 5: In lines 54-56, the two references cited are from the same journal, literature 15 was published earlier than literature 14, and literature 14 shows that the effect of inflation pressure on contact area is negligible, then according to the latest study is it possible to assume that the effect of inflation pressure is negligible, while the results of your study show that there is a certain effect of inflation pressure. Therefore, the description here needs to be revised.

Response 5: We reviewed the references 14, and found that “The positive effect of a reduction in inflation pressure on an increase of the contact area, and hence on the calculation of the mean pressure is only guaranteed for high load potentials.” in second paragraph of conclusion section. We have modified it, please see lines 47-50. Thanks

Point 6: In line 108, what is the basis for the selection of the inflation pressure values? In practical applications, the impact on the tire area should be reduced while ensuring normal tire operating conditions. Therefore the study of lower pressure values is meaningful for practical production applications.

Response 6: Yes, in practical applications, the impact on the tire area should be reduced while ensuring normal tire operating conditions. But for theoretical research, we want to make clear the influence rule of different tire pressures for contact area. For the 6.00-14 bias tire (four-ply rating), the recommended inflation pressure of 180 kPa corresponds to the maximum capacity of 3.70 kN (China, 2017). In order to investigate the the various of the contact area under different values of inflation pressure (overinflated, slightly underinflated, and seriously underinflated), 30 psi (207 kPa, overinflated), 20 psi (138 kPa, slightly underinflated), and 10 psi (69 kPa, seriously underinflated) of the tire pressure were selected in this paper. Please see lines 106-114. Thanks

Point 7: In lines 179-182, the variables in the formulas should be explained in the text.

Response 7: We added the explanation in lines 185-190. Thanks

Point 8: In line 188, ‘s’ should be capitalized.

Response 8: OK. Thanks

Point 9: The before interpolation and after interpolation curves have been compared in 3.2 Fractal dimension, so what is the role of Figure 7?

Response 9: Figure 7 shows a 3D curve of tire contact patterns within three lug cycles, which used to show the regularity of contact area of the ground surface.

Point 10: The coefficients in equation 11 do not correspond to the data in Table 4.

Response 10: Please see equation (9), where , so that , and .

Point 11: There is an error in the vertical coordinate unit of Figure 10(a).

Response 11: OK. Thanks

Point 12: There is an error in the name of the horizontal coordinate of Figure 10(b)

Response 12: OK. Thanks

Point 13: In lines 319-320, this part is not consistent with the results of the above study.

Response 13: It’s biggest rather than smallest. We modified in, please see line 323. Thanks

 

Reviewer 4 Report

This paper analyzes the influence of tractor tire contact area in a given terra mechanic system based on a multiple linear regression equation. The overall structure of the paper is good and the research describes an interesting area.

Linear regression assumes linearlity between dependent and independent variables however, it is prone to noise and overfitting. How the presented algorithm ensures both conditions of linearlity and robustness against noise?

Since, there are many computaitonal algorithms for the tire contact area on farmland, I was expecting a comparison of different algorithms with the regression equation presented by the authors. This will justify your choice of agorithm, Otherwise, there is no way to claim a superior estimation of the effects of speed, inflation pressure and tire load on the contact area between the tire and the soil.

Several typos in the text which needs correciton:

*pro-filer should be profiler  (line 121, 127, 167)

*calculation algorithms should be computational algorithms (line 49)

and so on ..

It is recommended to revise the paper for language correction and typos.

 

Moderate language corrections are suggested.

Author Response

Response to Reviewer 4 Comments

 

Point 1: Linear regression assumes linearlity between dependent and independent variables however, it is prone to noise and overfitting. How the presented algorithm ensures both conditions of linearlity and robustness against noise?

Response 1: Equation (11) is a comprehensive equation that incorporates the effect of speed, inflation pressure and vertical load on the contact area between the soil and tire. It contains 10 empirical coefficients of which only 6 are significant. It has an R² value of 90.80%, indicating an overall very good fit. Because all variables included in the study are equally spaced, we were able to use centered variables that guarantee no multicollinearity issues in model selection.Therefore, the prediction equation is robust with respect to coefficients and has high predictive ability. It is interesting to see that the contact area at the soil-tire interface varied as a quadratic function of the speed and inflation pressure when other two factors were fixed, and it varied as a linear function of tire load when inflation pressure was fixed. We have added these interpretations in the results and discussion. Please see lines 260-268.

Point 2: Since, there are many computaitonal algorithms for the tire contact area on farmland, I was expecting a comparison of different algorithms with the regression equation presented by the authors. This will justify your choice of agorithm, Otherwise, there is no way to claim a superior estimation of the effects of speed, inflation pressure and tire load on the contact area between the tire and the soil.

Response 2: In the section “Introduction”, we listed several references to indicate the influence factors of the contact area, which tire load, inflation pressure, and speed had greater influence to the contact. And, also we analyzed various methods of measurement and calculation of the contact area. All these methods had advantages and disadvantages, and no research indicated that a certain method has claim a superior estimation.

 

The reasons for choosing linear regression are as follows:

If an investigation involves quantitative factors or predictors and the interest is to understand the response within specific ranges of predictor variables (interpolation versus extrapolation), then regression is the correct approach. This is the principle behind creation of response surfaces that is widely used in science and engineering. In our case, all of the factors or predictors are quantitative (tire load, inflation pressure, and speed). So a well-planned regression experiment is appropriate in this case.  

Point 3: *pro-filer should be profiler  (line 121, 127, 167)

Response 3: OK. Thanks

Point 4: *calculation algorithms should be computational algorithms (line 49)

Response 4: OK. Thanks

Point 5: Several typos in the text which needs correciton:

*pro-filer should be profiler  (line 121, 127, 167)

*calculation algorithms should be computational algorithms (line 49)

Response 5: We checked and corrected relevant vocabulary in the paper. Thanks

Point 6:It is recommended to revise the paper for language correction and typos.

Response 6: OK. Thanks

 

 

 

 

 

Round 2

Reviewer 2 Report

The authors have corrected the text with dignity with my comments. They have added the extent of the involvement of Korean scientists in the work. They have increased the amount of source material. However, they have left the end of the bibliography blank, item No. 28, which should be removed before publication.

Editorial errors noted are for Lines: 116, 150, 190, 281, 303 no breaks between the text and the next part of the work e.g. drawing, next subsection etc.

In Line 247, move the subtitle to the next page.

Author Response

Response to Reviewer 2 Comments

 

Point 1: However, they have left the end of the bibliography blank, item No. 28, which should be removed before publication.

Response 1: OK. Thanks

Point 2: Editorial errors noted are for Lines: 116, 150, 190, 281, 303 no breaks between the text and the next part of the work e.g. drawing, next subsection etc.

Response 2: We checked the whole paper and modified all the problems of “No breaks”. Thanks

Point 3: In Line 247, move the subtitle to the next page.

Point 3: OK. Thanks

Reviewer 3 Report

1. There is an error in the labeling order of Figure 3.

2. The significance of the effects in Table 4 should be marked.

3. There is an error in Figure 10(c).

Moderate editing of English language required

Author Response

Response to Reviewer 3 Comments

 

Point 1: There is an error in the labeling order of Figure 3.

Response 1: 1. servo motor (x-direction); 2. cable carrier for surrounding and guiding the flexible cables; 3. laser sensor; 4. servo motor (y-direction); 5, 13. control box; 6. electric power; 7, 11. ruler with a level; 8. trundle with moving horizontal beam to which laser sensor is mounted; 9. ball screw pair with double optical axis; 10. tank chain; 12. laser head.

We checked again, and we ensured that there is no error in the labeling. Please see lines 136-139.

Point 2: The significance of the effects in Table 4 should be marked.

Response 2: We have deleted nonsignificant effects (eg x₃², x₁₂. x₁₃) and all effects listed in table 4 are significance. Thanks

Point 3: There is an error in Figure 10(c).

Response 3: OK. Thanks

Reviewer 4 Report

The manuscript has been thoroughly revised with sufficient improvements as per the reviewer's comments. However, two minor changes are required:

1) Numbering of results in the abstract looks odd. You can mention main contributions without numbering.

2) Figure 10, y-axis labels are merged with scale. You can label the y-axis in thousands (x1000) to gain more space for the label.

 

 

Minor improvements needed.

Author Response

Response to Reviewer 4 Comments

 

Point 1: Numbering of results in the abstract looks odd. You can mention main contributions without numbering.

Response 1: We adjusted the main contributions without numbering. Please see lines 18-24.

Point 2:Figure 10, y-axis labels are merged with scale. You can label the y-axis in thousands (x1000) to gain more space for the label.

Response 2: Thanks for your suggestions, and we modified figure 9 and figure 10.

Author Response File: Author Response.docx