Closed-Loop Supply Chain Design and Pricing in Competitive Conditions by Considering the Variable Value of Return Products Using the Whale Optimization Algorithm

Round 1

Reviewer 1 Report

       In this paper, a mathematical model considering the variable value of returned products is proposed for closed-loop supply chain management, which optimizes the location, inventory level and selling price of retailers to minimize the cost. Then, the hybrid algorithm is used to solve the model, and an example is given to demonstrate the proposed model and the hybrid algorithm.In general, the article is relatively complete and innovative, but there are some problems need to be improved.

1. In introduction, the discussion of research background and problems are weakly related to the research content. The history of supply chain management is too much, but it is not related to the main research content. It is suggested to simplify this part. This paper focuses on the research background and problems of the three key researches: closed-loop supply chain design, pricing and optimization algorithm.
2. It is suggested to supplement the research roadmap in introduction, which can help readers to sort out the research process and modules of the paper.
3. The level of literature review is weak. It is suggested that the literature review should be divided into three parts according to the main research contents of closed-loop supply chain design, pricing and optimization algorithm, and each part should be stratified according to the research differences, so as to avoid the stacking of literature content and increase the readability of the paper.
4. There is a lack of comprehensive summary of the shortcomings of previous studies. This paper only summarizes the shortcomings of closed-loop supply chain research, lack of pricing research and previous optimization algorithm.
5. Figure 1 shows the positive circulation process of the supply chain, and does not form a closed loop. It is suggested to revise and add necessary explanations.
6. Is there any previous literature to support the use of exponential function to simulate consumer demand? It is suggested to supplement supporting literature.
7. What are the advantages of combining whale algorithm with genetic algorithm? What are the shortcomings of the single algorithm? It is suggested to supplement the reasons for using hybrid algorithm.
8. It is suggested to elaborate the research conclusion in detail. And through the analysis of the research results, summed up the enlightenment of supply chain management practice.
9. Some references are too old. It is suggested to replace the references 10 years ago to ensure the timeliness of the research. In addition, the number of references needs to be increased. It is suggested to cite the research in related fields of core journals in recent three years to increase the persuasiveness of the paper.

Author Response

All your comments performed on the paper. the response to each comment is provided in the response letter Sincerely

     In this paper, a mathematical model considering the variable value of returned products is proposed for closed-loop supply chain management, which optimizes the location, inventory level and selling price of retailers to minimize the cost. Then, the hybrid algorithm is used to solve the model, and an example is given to demonstrate the proposed model and the hybrid algorithm. In general, the article is relatively complete and innovative, but there are some problems need to be improved.

1. In introduction, the discussion of research background and problems are weakly related to the research content. The history of supply chain management is too much, but it is not related to the main research content. It is suggested to simplify this part. This paper focuses on the research background and problems of the three key researches: closed-loop supply chain design, pricing and optimization algorithm.

Response: Thanks a lot, we revised the introduction based on your comments.

1. It is suggested to supplement the research roadmap in introduction, which can help readers to sort out the research process and modules of the paper.

Response: Thanks a lot, the roadmap added to section 1.

1. The level of literature review is weak. It is suggested that the literature review should be divided into three parts according to the main research contents of closed-loop supply chain design, pricing and optimization algorithm, and each part should be stratified according to the research differences, so as to avoid the stacking of literature content and increase the readability of the paper.

Response: Thanks a lot, we divided section 2 into three sections.

1. There is a lack of comprehensive summary of the shortcomings of previous studies. This paper only summarizes the shortcomings of closed-loop supply chain research, lack of pricing research and previous optimization algorithm.

Response: Thanks the shortcomings added to the end of section 2.

1. Figure 1 shows the positive circulation process of the supply chain, and does not form a closed loop. It is suggested to revise and add necessary explanations.

Response: Thanks a lot, Figure 1 amended.

1. Is there any previous literature to support the use of exponential function to simulate consumer demand? It is suggested to supplement supporting literature.

Response: we referred to the literature for the provided formulation of customer demand.

1. What are the advantages of combining whale algorithm with genetic algorithm? What are the shortcomings of the single algorithm? It is suggested to supplement the reasons for using hybrid algorithm.

Response: We added the advantage of hybrid algorithm both in section 4 and end of section 5.

1. It is suggested to elaborate the research conclusion in detail. And through the analysis of the research results, summed up the enlightenment of supply chain management practice.

Response: Thanks. Done exactly.

1. Some references are too old. It is suggested to replace the references 10 years ago to ensure the timeliness of the research. In addition, the number of references needs to be increased. It is suggested to cite the research in related fields of core journals in recent three years to increase the persuasiveness of the paper.

Response: Thanks a lot. We updated the literature based on your comment.

Reviewer 2 Report

See attach file.

Comments for author File: Comments.pdf

Author Response

All your comments performed on the paper. the response to each comment is provided in the response letter
Sincerely

 The main contribution of this paper should be outlined in introduction section. Please give a brief description. This would help the paper to have a better understanding of the real contributions of the paper.

Response: Thanks a lot, indicated the contribution of this research both in the introduction and end of literature review.

2. What is the superiority of the authors' work in comparison with those of others meta-heuristic algorithm, i.e. Particle swarm optimization (PSO), ant colony optimization (ACO), et.al? The dissemination of the results should be further explained.

Response: Thanks a lot, we explained the superiority of this algoritm in section 4 and also compared with other algorithms in section 5.

3. According to Figure 2 flowchart of the proposed hybrid WOA-GA algorithm, the pseudocode of the algorithm is given.

Response: Thanks a lot, pseudocode added exactly.

4. In Tables 2, 4, and 6, the Value levels defined for the parameters of the hybrid algorithm, please briefly explain the parameter selection method.

Response: Thanks. Done exatly.

5. The introduction paragraph should be presented more extensively; many papers were cited, but the outcomes of some of these mentioned papers on WOA algorithm were practically neglected. The following manuscripts can be added to the list of references, which are in the domain recent WOA algorithms and applies :

 (1) Optimize star sensor calibration based on integrated modeling with

hybrid WOA-LM algorithm. J. Intell. Fuzzy Syst. 38(3): 2683-2691 (2020).

(2) Lévy Flight Trajectory-Based Whale Optimization Algorithm for Global Optimization. IEEE Access 5: 6168-6186 (2017).

(3) Complex-valued encoding metaheuristic optimization algorithm: A comprehensive survey. Neurocomputing, 407: 313-342 (2020).

Response: Thanks a lot, we cited all of above papers.

6. The conclusions should be extended with more future work.

Response: Thanks a lot, we improved the conclusion based on your comment.

Reviewer 3 Report

The paper shows an implementation of a Whale Optimization Algorithm for designing a closed-loop supply chain. 

Time and gap results are very interesting, but It would be necessary to include a comparison between WOA and other methods identified in the literature review.  

How value levels were defined? The value levels defined for the parameters of the hybrid algorithm should be explained and supported with applications in the literature. 

A dataset with all the generated problems should be publicly available. 

Conclusions should address the limitations of the proposed method.

Author Response

All your comments performed on the paper. the response to each comment is provided in the response letter
Sincerely

Time and gap results are very interesting, but It would be necessary to include a comparison between WOA and other methods identified in the literature review.  

Response: Thanks a lot, we added the required comparison at the end of section 5.

How value levels were defined? The value levels defined for the parameters of the hybrid algorithm should be explained and supported with applications in the literature. 

Response: Thanks a lot, we used try and error for the value of parameters and mentioned it in the context.

A dataset with all the generated problems should be publicly available.

Response: Thanks a lot, we used random generator syntax in Matlab to generate the data.

Conclusions should address the limitations of the proposed method.

Response: Thanks a lot, we improved the conclusion based on your comment.

Reviewer 4 Report

The paper is in line with the contemporary topics of research in the field of Supply Chain Management. Authors are examining a variable value of return which recently grew significantly in modern supply chains supported by electronic commerce. This variable is becoming the problem for optimization of stocks and value flow, especially in retail companies. But influences supply chains in general. Therefore, paper is a valuable contribution both to retail management literature and to supply chain management field. Therefore we recommend publication of the paper.

Hovewer, paper can be improved:

• the theoretical insights into whale optimization algorithm is missing. As there are readers who are not familiar with WOA, please add more definitions and explain this algorithm in general prior to your analysis
• Authors mention Taguchi loss function, but again, there is no clear explanation or basic information about it, nor there is a reference to the literature on this function!
• In conclusion part authors should emphasize limitations of the paper and provide some suggestions for future research of the topic

Author Response

Thanks for your comments. the respone :

the theoretical insights into whale optimization algorithm is missing. As there are readers who are not familiar with WOA, please add more definitions and explain this algorithm in general prior to your analysis

Response: Thanks a lot, we improved the explanation of WOA by using some other references.

Authors mention Taguchi loss function, but again, there is no clear explanation or basic information about it, nor there is a reference to the literature on this function!

Response: Thanks a lot, we updated the information of taguchi and provided the references for this method.

In conclusion part authors should emphasize limitations of the paper and provide some suggestions for future research of the topic

Response: Thanks a lot, we improved the conclusion based on your comment.