A Suitability Evaluation Method of Urban Underground Space Based on Rough Set Theory and Conditional Entropy: A Case Study in Wuhan Changjiang New Town

Round 1

Reviewer 1 Report

The article discusses the problem of designing the use of the underground space of a megalopolis for complex geological conditions, characterized by intense underground waters, karst phenomena, loose soils and the presence of a large river on the surface. The goal is to form a set of features of the geological state of the underground space and assess their importance for subsequent accounting in the engineering development of the underground space of the metropolis. An important issue is the identification of areas that should be excluded from development due to the increased likelihood of destructive geological processes. As a mathematical tool for assessing the importance of geological factors, it is proposed to use correlation analysis in conjunction with the apparatus of the theory of rough sets, which is a section of the general theory of fuzzy sets. As an example, the city of Wuhan in China is considered, for which maps of zones of underground space have been built along with indices of their suitability for engineering development.

Author Response

Thanks for reviewer pleased with both the structure and the content of our paper. Our research aims to propose a suitability evaluation method of urban underground space based on rough set theory and conditional entropy, and select the Wuhan Changjiang New Town as an example. The results show that the underground space suitability evaluation model is in good agreement with the reality, and the parameter selection and weight determination are scientific and reasonable, and are basically free from human factors. This method can provide reference for related engineering cases.

Author Response File: Author Response.docx

Reviewer 2 Report

This paper establishes a suitability evaluation model based on rough set theory and conditional entropy. A case study on the suitability of underground space development and utilization in the starting area of Wuhan Changjiang New Town is also proposed. The idea is interesting. However, the paper can be improved by considering the following issues. 

1. The abstract should be a little changed. To more emphasize contributions and novelty.

2. The introduction section is inadequate. Please add some recent articles to improve the literature. Many noteworthy research articles in this direction are not considered in this present version. The authors are advised to survey the literature more to upgrade the present form.
3. The introductory section must appropriately highlight the motivations and objectives of this research by reporting what are the performance improvements compared to well-known fuzzy-based approaches.
4. The authors fail to properly motivate their research. Why rough set theory is applied? 

5.  There is no conceptual comparison with existing approaches, no discussion on the benefits and drawbacks of the new approach. Thus discussions and comparative analyses should be added, also it is important to compare your method with literature ones.

6. The description of future research directions should be extended in the Conclusion Section. Must emphasize the rationale and enhancements for future research based on the findings of this study.

7. Some of the references are rather old and some recent studies need to be added.

Author Response

This paper establishes a suitability evaluation model based on rough set theory and conditional entropy. A case study on the suitability of underground space development and utilization in the starting area of Wuhan Changjiang New Town is also proposed. The idea is interesting. However, the paper can be improved by considering the following issues.

Reply: Thanks for the reviewer for recognizing the innovation of our paper, and also thanks for the reviewer's criticism and correction which will help us improve this paper. These comments are very important and we have responded point-to-point. 

1. The abstract should be a little changed. To more emphasize contributions and novelty.

Reply: Thank you! We have revised it according to your suggestion in the current paper. The revised text is highlighted in red as follow.

Abstract: In order to make full use of underground space resources, reasonably determine the development function and scale, it is important to evaluate the suitability evaluation of urban underground space (UUS). The development and utilization of underground space is affected by many factors, such as topography, geomorphology, geotechnical characteristics, hydrogeology, and so on. Taking the starting area of Changjiang New Town in Wuhan as a case study, this paper introduce the rough set theory and conditional entropy, and establishes a suitability evaluation model of UUS. Rough set theory is used to construct decision information table, preprocess sample data and classify knowledge base, while the conditional entropy is employed to calculate the attributes’ own and relative importance. Then, the fuzzy comprehensive evaluation method, the most unfavorable grade discrimination method and the exclusive method are used to evaluate the model, and the partition map of regional underground space development suitability is obtained. In this method, any prior knowledge and additional information will be not needed except the sample data, and the obtained weights are more objective and reasonable. The results show that the overall suitability of underground space development and utilization in the starting area of Wuhan Changjiang New Town is good. 

2. The introduction section is inadequate. Please add some recent articles to improve the literature. Many noteworthy research articles in this direction are not considered in this present version. The authors are advised to survey the literature more to upgrade the present form.

Reply: Thanks to the reviewers! We have carried out literature research on relevantstudies in recent years, and the revised text is highlighted in red. Hoping that the revised content can meet the requirements of reviewers. Additional references are listed as follow:

2. Bobylev N., Sterling R. Urban underground space: A growing imperative. Perspectives and current research in planning and design for underground space use. Tunn Undergr Sp Tech, 2016, 55: 1-4.

5. Peng J, Peng F L. A GIS-based evaluation method of underground space resources for urban spatial planning: Part1 method-ology. Tunn Undergr Sp Tech, 2018,74:82-95.

6. Peng J, Peng F L. A GIS-based evaluation method of underground space resources for urban spatial planning: Part 2 application. Tunn Undergr Sp Tech, 2018, 77: 142-165.

9. Zhou B, Gui Y, Xie X, et al. A measurable evaluation method of visual comfort in underground space by intelligent sorting and classification algorithms. Undergr Space, 2021.

13. Youssef A M, Pradhan B, Tarabees E. Integrated evaluation of urban development suitability based on remote sensing and GIS techniques: contribution from the analytic hierarchy process. Arab J Geosci, 2011, 4(3-4): 463-473.

14. Wang X, Zhen F, Huang X, et al. Factors influencing the development potential of urban underground space: Structural equation model approach. Tunn Undergr Sp Tech, 2013, 38: 235-243.

15. Liu D, Wu L, Yang Y. A hybrid weight assignment model for urban underground space resources evaluation integrated with the weight of time dimension. Applied Sciences, 2020, 10(15): 5152.

16. Duan Y, Xie Z, Zhao F, et al. Suitability of underground space development in plateau cities based on geological environment analysis: Case study in Kunming, China. J Urban Plan Dasce, 2021, 147(2): 05021014.

18. Sinha S K, McKim R A. probabilistic based integrated pipeline management system. Tunn Undergr Sp Tech, 2007, 22(5-6): 543-552.

19. Peng J, Peng F L, Yabuki N, et al. Factors in the development of urban underground space surrounding metro stations: A case study of Osaka, Japan. Tunn Undergr Sp Tech, 2019, 91: 103009.

20. van der Hoeven F, Juchnevic K. The significance of the underground experience: Selection of reference design cases from the underground public transport stations and interchanges of the European Union. Tunn Undergr Sp Tech, 2016, 55: 176-193.

21. Ulucay V. A new similarity function of trapezoidal fuzzy multi-numbers based on multi-criteria decision making. J Inst Sci Technol 2020, 10(2):1233–1246.

22. Uluçay, V., Deli, I., & Şahin, M. Trapezoidal fuzzy multi-number and its application to multi-criteria decision-making problems. Neural Computing and Applications, 2018, 30(5), 1469-1478.

28. Bakbak D., Uluçay V., Şahin M. Intuitionistic trapezoidal fuzzy multi-numbers and some arithmetic averaging operators with their application in architecture. 6th International Multidisciplinary Studies Congress (Multicongress’19) Gaziantep, Türkiye, 2019. 

3. The introductory section must appropriately highlight the motivations and objectives of this research by reporting what are the performance improvements compared to well-known fuzzy-based approaches.

Reply: We have clarified the performance improvements compared with the well-known fuzzy-based approaches and highlight the motivations and objectives of this research. The modifications are as follows:

      However, at the present stage, the index weighting method of UUS engineering geological suitability evaluation is relatively simple, mostly using some fuzzy-based approaches, such as analytic hierarchy process and entropy method, and less involving other subjec-tive and objective weighting methods, such as correlation matrix method (Gulin meth-od)[14], sequential scoring method[18], principal component analysis[19], CRITIC method[20] , rough set theory [21, 22], etc. So there are many subjectivity and randomness, and the task is time-consuming.

      In this paper, based on the status quo of underground space development and utilization in the starting area of Wuhan Changjiang New Town and relevant data, a suitability evaluation model is developed. Rough set theory is used to construct decision information table, preprocess sample data and classify knowledge base. The con-cept of conditional entropy is introduced to calculate the attributes' own and relative importance. Finally, the attribute weight of each classification index is obtained through standardization. On this basis, the fuzzy comprehensive evaluation method, the most unfavorable grade discrimination method and the exclusive method are used to evaluate the model, and the partition map of regional underground space development suitability is obtained.

4. The authors fail to properly motivate their research. Why rough set theory is applied?

Reply: Accurately determining the importance of each factor is an important prerequisite for the evaluation results to conform to the reality. In previous studies, analytic hierarchy Process (AHP) and expert scoring method were mostly used to determine the influence weight of each factor based on the subjective information of decision-makers. However, this method relies too much on the level and ability of decision-makers, and the weight assignment may not be reasonable, resulting in great differences in evaluation results. In this paper, the method of combining rough set and conditional entropy is adopted to fully reflect the objectivity of data without providing any prior information outside the sample data set. Then the weight determination is more reasonable and the evaluation result is more in line with the reality.

5. There is no conceptual comparison with existing approaches, no discussion on the benefits and drawbacks of the new approach. Thus discussions and comparative analyses should be added, also it is important to compare your method with literature ones.

Reply: Thanks for the reviewer's criticism and correction. Actually, we describe the innovation of the method in Section 3.2. The description contain but not only “Different indexes have different influences on the evaluation results, that is, they are endowed with different weights in the calculation process. Accurate determination of the importance of each factor is an important premise for the evaluation results to conform to the reality. In previous studies, analytic hierarchy process (AHP) and expert scoring method are mostly adopted. This method based on the decision makers' subjective information to determine the weight of each factor relies too much on the level and ability of the decision makers, and the weight is not necessarily reasonable. So the evaluation results may appear large differences. In this paper, the method of combining rough set and conditional entropy is adopted, which can fully reflect the objectivity of the data without providing any prior information outside the sample da-ta set. Thus, the weight determination is more reasonable and the evaluation results are more in line with the reality.” What’s more, we also added a description of the innovation points of the method in the introduction.

6. The description of future research directions should be extended in the Conclusion Section. Must emphasize the rationale and enhancements for future research based on the findings of this study.

Reply: Thanks for the reviewer's criticism and correction. We have extended the description of future research directions. The modifications are as follows

This paper evaluates the development and utilization of underground space based on the suitability of engineering geology. Factors such as potential value of underground space development and utilization, amount of resources and developable volume are not considered in the model. Therefore, future research will be based on geological factors evaluation, fully consider the role of economic value, resource amount, etc., to make the evaluation more comprehensive.

7. Some of the references are rather old and some recent studies need to be added.

Reply: Thanks to the reviewers! We have carried out literature research on relevant studies in recent years, and the revised text is highlighted in red, and references are listed in question 1.

Author Response File: Author Response.docx

Reviewer 3 Report

The topic of the paper is interesting, but there are some points that need to be addressed to improve the quality of the paper.

1-The authors should clearly justify the motivation of this study in the introduction section.

2-What are the limitations of the proposed model?

3-In order to give the reader more information on fuzzy set theory and the following references must be added for a powerful publication:

• Ulucay V (2020) A New similarity function of trapezoidal fuzzy multi-numbers based on multi-criteria decision making. J Inst Sci Technol 10(2):1233–1246.

• Uluçay, V., Deli, I., & Şahin, M. (2018). Trapezoidal fuzzy multi-number and its application to multi-criteria decision-making problems. Neural Computing and Applications, 30(5), 1469-1478.

• Bakbak D, Uluçay V, and Şahin, M, 2019b. Intuitionistic Trapezoidal Fuzzy Multi-Numbers and Some Arithmetic Averaging Operators with Their Application in Architecture. 6th International Multidisciplinary Studies Congress (Multicongress’19) Gaziantep, Türkiye

Author Response

The topic of the paper is interesting, but there are some points that need to be addressed to improve the quality of the paper.

Reply: Thanks for the reviewer for recognizing the innovation of our paper, and also thanks for the reviewer's criticism and correction which will help us improve this paper. These comments are very important and we have responded point-to-point. 

1. The authors should clearly justify the motivation of this study in the introduction section.

Reply: Thanks to the reviewers! We have carried out the motivation and innovation of this study in the introduction section. Hoping that the revised content can meet the requirements of reviewers, and the revised text is highlighted in red. 

2. What are the limitations of the proposed model?

Reply: In the evaluation of undesirable geological phenomena, if the superposition calculation is used for karst ground collapse and soft soil settlement, the score of the area with undesirable geological phenomena will be too average, which is different from the actual influence result. Therefore, the index of undesirable geological phenomenon is degraded by the most unfavorable grade discrimination method. However, it is difficult to find out the bad geological phenomena, which leads to the over-average regional score in the calculation of bad geological phenomena. 

3. In order to give the reader more information on fuzzy set theory and the following references must be added for a powerful publication:

Reply: Thanks for the reviewer's criticism and correction. We have realized that the description about fuzzy set theory is lacking, so we have been added some related descriptions and some powerful references.

21. Ulucay V (2020) A New similarity function of trapezoidal fuzzy multi-numbers based on multi-criteria decision making. J Inst Sci Technol 10(2):1233–1246.

22. Uluçay, V., Deli, I., & Şahin, M. (2018). Trapezoidal fuzzy multi-number and its application to multi-criteria decision-making problems. Neural Computing and Applications, 30(5), 1469-1478.

28. Bakbak D, Uluçay V, and Şahin, M, 2019b. Intuitionistic Trapezoidal Fuzzy Multi-Numbers and Some Arithmetic Averaging Operators with Their Application in Architecture. 6th International Multidisciplinary Studies Congress (Multicongress’19) Gaziantep, Türkiye.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The authors have updated the manuscript as per the reviewer's comments. 

Reviewer 3 Report

I think, good work, the paper is acceptable.