Experimental Investigation on Fragmentation Identification in Loose Slope Landslides by Infrared Emissivity Variability Features
Round 1
Reviewer 1 Report
The manuscript by Liu et al. presented research using an thermal infrared imager studying the effects of particle size and observation/zenith angles. I am having a hard time understanding the authors, English language improvements are necessary for publication.
I have some concerns:
1) L165 says the temperature recognition accuracy of the imager is to 0.1 K, why are you providing data with better accuracy in Figures 6-8 and Table 5?
2) Generally emissivity is defined as the ratio of the radiation of a surface to that of a black body. In the manuscript the author refers to the emission portion within the full spectrum. Please consider using another term.
3) The authors mentioned in L377 that the f(sigma') cannot be calculated. Can it be calculated if the authors put 9 specimens of the same lithology and same grain size for measurements, i.e., use the same sample to study the effects of zenith angles?
4) L303 Why the contributions from the environment is not the epsilon of the surrounding environment times fourth power of T? If the surrounding contribution is those radiation irradiated to the surface and then reflected into the imager, then (1-epsilon(lamda1,lamda2)) should be replaced with the reflectance of the surface; if the surrounding contribution is those radiation irradiated directly into the imager, then (1-epsilon(lamda1,lamda2)) should be 1.
5) For the effects of particle sizes, do the mineral crystal grains affect the experiment? The mineral grain sizes can be measured under a microscope.
6) Figures 6-8 make the T/K axes consistent between different sigmas to make it easy to compare. Make the arrangement of E1 in Figure 6 the same as Figures 7 and 8. Figure legends are also necessary in Figures 7 and 8. Figure 9 please use colors to isolate different sigmas, signals are easy to overlap and hard to identify.
7) For Figures 6-8 Can you explain the trends among different sigmas? Why temperatures are 50>30>40>20 for marble? Why temperatures for -20 and 20 are between -10 and 10 for marble? Why temperature trends for different rocks are different?
Some other comments, please check the highlighted text in attachment.
L53 the sentence is not closely related to the previous contents
L58 citations?
L63 please rewrite
L66 please rewrite
L68 please rewrite
L81 platforms
L83 do you mean "米“字型？I guess it's only understandable by Chinese readers.
Table 3 too many significant digits
L121 sieves
L141 only the maximum bounds add up to 100, same in the next paragraph
L148 hornblende
L150 Biotite
L154 clastic rocks are not minerals
L158 295.25±0.1K
L159 from
L167 What is a focal ratio?
L170 angular resolution?
L175 Isn't it simplified as T in L174?
L284 number the equations and use number to refer them
L288 When introducing the terms, do not add the unit in the end of the sentence.
L289 redundant
L291 please rewrite
L297 redundant
L300 includes those
L304 redundant
L309 Can you specify how long have the specimens have been kept there? How long has the room temperature been kept at the set value? When the instruments were setup for measurements did that affect the temperatures? The imager measurements might generate some heat that may affect the environment and change the epsilon<sub>sur<sub>.
L319 what is this which
L348 solving
L364 can you explain "unify"?
L372 EQ. 7,
L391 can you explain unify?
L397 this term has never been introduced
L397 please rewrite
L417 why is 1mm important and used to classify particle sizes?
Comments for author File: 
Comments.pdf
I have to say that English language proficiency presented in this paper is poor, I am having a hard time understanding the authors. I'll recommend the authors to use an English editing service or to have a good English writer who understands thermal imaging rewrite the manuscript. I have tried editing the first page of the manuscript, please check the highlighted text in the attachment:
L13 a rock
L15 tests, of granite, ... samples
L16 rock fragments
L18 directions, angles
L24 changes of the law equivalent emissivity of all rock fragments with particle sizes are consistent
L28 no capital
L34 a loose slope
L35 remove highlighted
L38 the subject should be IBT, not the physical parameter
L41 infrared radiation studies
L42 simply
L43 the mineral compositions
L45 sizes
Author Response
We appreciate your comment.
Author Response File: 
Author Response.docx
Reviewer 2 Report
1、The content of this paper is to explore the changing law of material emissivity with its particle size.
However, as its current state, it is not clear how to use the law to identify fragmentation of the loose slope landslides as indicated by the title and what's the effect of doing this.
Therefore, authors should add more materials to answer above two questions.
2、The objective of this paper is to discover the effect of particle size on the infrared emissivity of rock fragments, which is not consistent with the "fragmentation identification..." indicated by the paper title, please add a section to the paper addressing the usefulness of your findings in the "fragmentation identification in the loose slope landslides".There are also some errors in the manuscript. Please see them in the attached PDF file and correct them throughout the whole manuscript.
For these above reasons, I suggest a major revision to this manuscript.
Comments for author File: Comments.pdf
There are some errors in the manuscript. Please correct them throughout the whole manuscript.
Author Response
We appreciate your comment.
Author Response File: Author Response.docx
Reviewer 3 Report
The paper carried out infrared imaging test on rock fragments with granite, marble and sandstone being examples. The paper is readability and fit to this journal. But I have some comments before it is accepted.
1. A more in-depth introduction is needed. What's innovative about this paper.
2. The text in Fig. 5 is difficult to read.
Author Response
We appreciate your comment.
Author Response File: Author Response.docx
Reviewer 4 Report
This manuscript explores the relationship between particle sizes in rocks and their infrared emissivity. It's interesting because it helps with thermal infrared remote sensing for loose slope landslides. However, there are a few points to consider for improvement: 1. Despite the authors' efforts to minimize shading, indoor background radiation remains a challenge. The authors should address how they plan to mitigate this issue. 2. The choice of 9 specific particle sizes for analysis in Table 4 and Fig. 4 should be explained. Why were these sizes selected? 3. The article's title emphasizes slope stability, but there is currently insufficient content related to this topic. Authors should incorporate more relevant literature on slope stability to align with the title. 4. Revisions are needed to enhance the quality of the figures. For example, appropriate labels should be added to Figure 2. Overall, some minor revisions are necessary to improve the manuscript.
Minor editing of English language required.
Author Response
We appreciate your comment.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
I thank the authors for taking my comments and suggestions into their consideration. However, their replies and modifications did not resolve my concerns.
1) Emissivity is how well an emitter radiates energy compared with a perfect emitter (a black body), that is the ratio of the radiation from a surface to that of a black body at any wavelength. Please find another term to describe the emission proportion.
2) Please rewrite the abstract, the narration is not continuous and the logic is broken among sentences.
3) L42-70, please explain why are these studies related to your research.
4) How are the zenith angles calculated for E2? I tried the numbers and got different results: atand(2/0.76) = 69.1932; tand(2/1.15) = 60.1011; atand(2/1.68) = 49.9697; atand(2/2.38) = 40.0415.
5) Why are the IBTs significantly lower than the room temperature? They are near 285K and room T is 295K.
6) Figure 6-8, what I meant is to shift the y axes and hold one single temperature value, say 285.2K, at the same level, so results from different sigmas can be easily compared. See example at the end of the attachment.
7) For E1 in Fig. 6, sigma=0, why the range on delta T is 0.6K and on T is 0.4K? Same for sigma=-20. For E2 in Fig. 6, the range on delta T is 0.5K and on T is 0.1K.
8) For E2 in Fig. 6, the widths of the bars for different points are not the same.
9) Can you explain the trends among different sigmas? Why temperatures are 50>30>40>20 for marble? Why temperatures for -20 and 20 are between -10 and 10 for marble? Why temperature trends for different rocks are different? The authors didn't add any explanations to these questions. They only added that there is also a linear correlation with T and fragment size in small angle changes of E1 (Left side in Figure 9), but the correlation in larger angle changes of E2 (Right side in Figure 9) is not obvious.
10) For Fig. 9 the authors wanted to use black and white to be more formal and academic, but the problem with that is, the symbols are easy to overlap and hard to identify in Fig. 9. If you decrease the sizes of symbols to avoid overlaps, then they are smaller and hard to identify; if you increase the sizes then they overlap more.
11) The authors added a section 4.4 but didn't quite explain how is this section related to the experiment. L487, L489, L490, L492, you are repeating yourselves but give no new information.
Some other comments:
L29, do not capticalize remote sensing rock mechanics
L39, does a thermal imaging camera only observe the IBT? Maybe replace "the physical parameter".
L42, repetitive use of study.
L45, do not use capital letters.
L48, what is Cv?
L71, infrared is a general term, please be more specific. If you use "widely", one citation is not enough.
L72, do not capticalize
L83, interpretations of abnormal rock IBT
L84-85, still not closely related to the previous contents. Why do you introduce machine learning here?
L86-87, Factors controlling the measured infrared emission characteristics of rocks include object properties like physical temperature, surface morphology as well as observation settings like orientation.
L98, Preliminary research has shown the influence of fragment sizes on the measured equivalent emissivity epsilon_<sub>f<sub> under strong background radiation.
L100, I still cannot understand this sentence.
L116, consider adding a sentence in transition like "We have designed two experiments to simulate the observations from the two platforms."
L117, please choose another way of expression and avoid using a Chinese character.
L176, if you add the maximum proportions of calcite and dolomite, 50%+40% = 90%, then the minimum proportion of quartz is 10%.
L195, the temperature is controlled, I guess "accuracy" is not appropriate, just use 295.25+-0.1K is fine.
L208, 0.6 mrad, do not use Mrad.
L228, equations should all be numbered.
L536, mechanics.
Comments for author File: Comments.zip
English language still needs improvement.
Author Response
Thanks for your comments. We revise the paper in all aspects.
Author Response File: Author Response.docx
Reviewer 2 Report
For authors have modified the manuscript according to the proposed comments, I suggest an acceptance for publication to this manuscript after minor revision.
However, there are still some errors/suggestions in the manuscript. Please see them in the attached PDF file and correct them throughout the whole manuscript.
Comments for author File: Comments.pdf
there are still some errors in the manuscript. Please see them in the attached PDF file and correct them throughout the whole manuscript.
Author Response
We appreciate your comment. We revise the paper in all aspects.
Author Response File: Author Response.docx
