Material Flow Optimization as a Tool for Improving Logistics Processes in the Company

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper analyzes the current state of material flow at a manufacturing plant.  However, several areas could benefit from revisions to enhance its clarity, rigor, and impact.

• The abstract effectively summarizes the study's scope and findings. However, it could be more concise and highlight the novelty of the proposed methodology more prominently. The introduction should provide a stronger theoretical foundation, explicitly linking material flow optimization to broader logistics and supply chain management concepts. Consider adding a brief literature review to contextualize the study and demonstrate its contribution to existing knowledge.
• While the checkerboard table and cost calculation formulas are valuable tools, the methodology section needs more detail. Explain the criteria for selecting the two optimization variants and justify the choice of specific analytical tools. Provide a more detailed explanation of how the checkerboard table is used and how the formulas are derived. Clarify the assumptions made in the cost calculations, especially regarding operational costs and personnel expenses.
• The results section presents the cost calculations effectively, but it could benefit from visual aids, such as charts or graphs, to illustrate the cost savings and ROI. The discussion section thoroughly compares the two variants but could be expanded to include a more in-depth analysis of the practical implications of the findings. Discuss the potential challenges in implementing the proposed solutions and suggest strategies to mitigate them. Also, elaborate more on the environmental impact of the proposed changes, linking them to sustainable transport goals.
• Ensure consistency in terminology and formatting throughout the paper. Pay close attention to the presentation of tables and figures, ensuring they are clearly labeled and referenced in the text. Consider adding a section on limitations of the study, acknowledging any potential biases or constraints.
• The future research section is comprehensive but could be more focused. Prioritize the most promising avenues for further investigation and explain how they would build upon the current study's findings. Consider including a brief discussion of the potential impact of emerging technologies, such as AI and automation, on material flow optimization.

 

Comments on the Quality of English Language

The English could be improved to more clearly express the research.

Author Response

Dear editor and reviewers,

We sincerely thank you to review team for the insightful and constructive comments on our manuscript. The manuscript has been carefully revised according to the reviewers comments.

We look forward to hearing from you on the revised manuscript. In the remainder of this letter, we provide detailed answers to each of the comments. We remind you that we have tried to process all reviewers' comments and they have all been incorporated into the article.

Comments from the Reviewers:

Reviewer 1:

The paper analyzes the current state of material flow at a manufacturing plant.  However, several areas could benefit from revisions to enhance its clarity, rigor, and impact.

The abstract effectively summarizes the study's scope and findings. However, it could be more concise and highlight the novelty of the proposed methodology more prominently. The introduction should provide a stronger theoretical foundation, explicitly linking material flow optimization to broader logistics and supply chain management concepts. Consider adding a brief literature review to contextualize the study and demonstrate its contribution to existing knowledge.

• Thank you. The abstract has been carefully revised according to the requirements of both reviewers.
• The Introduction section has been supplemented with the required information. Changes are highlighted in yellow.
• The Literature Review section has been thoroughly revised and expanded based on the requirements of both reviewers. Therefore, we do not consider adding a brief literature review to the Introduction section.

While the checkerboard table and cost calculation formulas are valuable tools, the methodology section needs more detail. Explain the criteria for selecting the two optimization variants and justify the choice of specific analytical tools. Provide a more detailed explanation of how the checkerboard table is used and how the formulas are derived. Clarify the assumptions made in the cost calculations, especially regarding operational costs and personnel expenses.

• Thank you for your comment. The criteria have been added and explained in the Results section.
• All other requirements regarding the checkerboard table have been incorporated and described in the Methodology section. The methodological additions provide a detailed justification for selecting optimization variants, an expanded explanation of the checkerboard table as an analytical tool, and a more precise description of cost calculations, including assumptions. This approach enhances the transparency of the calculations and allows for a better understanding of the impacts of the proposed solutions on the operation of the manufacturing company.

The results section presents the cost calculations effectively, but it could benefit from visual aids, such as charts or graphs, to illustrate the cost savings and ROI. The discussion section thoroughly compares the two variants but could be expanded to include a more in-depth analysis of the practical implications of the findings. Discuss the potential challenges in implementing the proposed solutions and suggest strategies to mitigate them. Also, elaborate more on the environmental impact of the proposed changes, linking them to sustainable transport goals.

• Thank you for your valuable feedback. Regarding your suggestion to include visual aids, such as graphs, to illustrate cost savings and return on investment, we acknowledge the importance of graphical representation for improved clarity of results. However, considering the scope and structure of the article, we have chosen to represent savings and return on investment through detailed calculations, which provide a clear and comprehensive comparison of the proposed optimization variants. Additionally, a visual comparison of costs and savings is presented in Figure 7 in the Discussion section, where the financial impact of the optimization measures is displayed in a structured manner. Therefore, we believe that additional graphical representation would be redundant.
• All other requested modifications have been incorporated into the Discussion section and are highlighted in yellow.

Ensure consistency in terminology and formatting throughout the paper. Pay close attention to the presentation of tables and figures, ensuring they are clearly labeled and referenced in the text. Consider adding a section on limitations of the study, acknowledging any potential biases or constraints.

• Thank you for your comment. This has been added and discussed in the Discussion section.

The future research section is comprehensive but could be more focused. Prioritize the most promising avenues for further investigation and explain how they would build upon the current study's findings. Consider including a brief discussion of the potential impact of emerging technologies, such as AI and automation, on material flow optimization.

• Thank you. This has been included in the Discussion section.

• The English could be improved to more clearly express the research.

• Thank you for your valuable comment. The English language has been reviewed throughout the entire document.

Best regards

Reviewer 2 Report

Comments and Suggestions for Authors The paper aims to maximize material flow in a manufacturing firm to achieve maximum logistics efficiency, reduce operating expenses, and green supply chains. Through the examination of one of the Veselí nad Lužnicí factories in detail, the authors identify inefficiencies that exist and recommend two optimization options: replacing external semifinished goods (SF) transport with internal processes and replacing external finished goods (FG) transport with an internal fleet. The study contributes to the literature through the utilization of a checkerboard table methodology, cost models, and return on investment (ROI) estimates in evaluating the feasibility of such optimization efforts. The strengths of the paper are its well-organized framework, exhaustive quantitative analysis, and relevance to manufacturing and logistics companies.
General comments
The research overlooks the possibility that there may be some extraneous variables at play, such as volatile fuel prices or uncertain levels of demand, which will affect the applicability of solutions. While a checkerboard table is a good visualization tool, it may have been employed in addition by any other statistical model or simulation modeling to reach a definitive conclusion. Lastly, the research assumes that warehousing expansion is not possible yet fails to consider other storage productivity measures that will reduce the dependence on external transportation.
The literature review can further be enriched through a comprehensive scrutiny of Industry 4.0 technology, comprising real-time observation, AI-governed planning of logistics, and digital twin simulations, which are increasingly involved in modern-day supply chain management. Besides, even if the sources mentioned are relevant, there are also some mentioned references that are less up to date or fail to cite current progress in automated material handling systems. The essay also does not evidently state what the specific knowledge gap it attempts to fill since the issue of material flow optimization has already been well researched by earlier studies. More emphasis on how this piece of work serves to fill some gap in the literature—i.e., rebutting industry-specific constraints or propounding a fresh methodological procedure—would render the review more rational.
In-depth comments:
Lines 8–26) The abstract is referred to in "modern analytical tools, including visualization techniques and efficiency assessment models" but is not followed with examples. Giving particular examples such as simulation packages or mathematical modelling techniques would serve to establish lucidity.
(Lines 13–14) The study is performed on a Veselí nad Lužnicí plant, but why they used this plant is not indicated. Was it because it was inefficient, like in the sector, or due to the fact that data were available? It would make the study more valid if the reason were included.
(98–150) Review of literature mentions "material flow optimization" but typically oscillates between synonym but not identical words such as "supply chain optimization," "warehouse efficiency," and "facility layout." More specifically would be clarification of whether such are subtopics under material flow optimization or replaceable topics.
(Line 165) The process of material flow optimization is depicted by Figure 1 but does not show how a step comes after the subsequent stages. Adding brief explanations or transition words to the text would enable readers to better imagine the sequence of steps.
(Tables 1–4, Lines 381–411) The tables of cost for forklift, staff, and transport fee use different levels of decimal precision (e.g., some are rounded to two decimals, others to five). Consistency in numerical formatting would enhance clarity and comparison.
(626–650) No mention of environmental effects. In the interest of emphasizing optimization of logistics, savings of CO2 due to lower transport lengths or fuel efficiency gains must be measured and considered a second-order gain.
(Lines 636–650) It is recommended in the paper that further research in IoT and machine learning for streamlining material flow is prudent, but this is not linked back to the case study. Are these technologies applied to Veselí nad Lužnicí's factory or are they generic recommendations? Creating a real-life context for the innovations would improve the conclusion.

Author Response

Dear editor and reviewers,

We sincerely thank you to review team for the insightful and constructive comments on our manuscript. The manuscript has been carefully revised according to the reviewers comments.

We look forward to hearing from you on the revised manuscript. In the remainder of this letter, we provide detailed answers to each of the comments. We remind you that we have tried to process all reviewers' comments and they have all been incorporated into the article.

Comments from the Reviewers:

Reviewer 2

The paper aims to maximize material flow in a manufacturing firm to achieve maximum logistics efficiency, reduce operating expenses, and green supply chains. Through the examination of one of the Veselí nad Lužnicí factories in detail, the authors identify inefficiencies that exist and recommend two optimization options: replacing external semifinished goods (SF) transport with internal processes and replacing external finished goods (FG) transport with an internal fleet. The study contributes to the literature through the utilization of a checkerboard table methodology, cost models, and return on investment (ROI) estimates in evaluating the feasibility of such optimization efforts. The strengths of the paper are its well-organized framework, exhaustive quantitative analysis, and relevance to manufacturing and logistics companies.

General comments
The research overlooks the possibility that there may be some extraneous variables at play, such as volatile fuel prices or uncertain levels of demand, which will affect the applicability of solutions. 

• Thank you for your valuable comment. This has been added to the Discussion section.

While a checkerboard table is a good visualization tool, it may have been employed in addition by any other statistical model or simulation modeling to reach a definitive conclusion. Lastly, the research assumes that warehousing expansion is not possible yet fails to consider other storage productivity measures that will reduce the dependence on external transportation.

• Thank you. This has been added to the Methodology section. Regarding the issue of warehouse capacity expansion and reducing dependence on external transportation, the study operates under the assumption that physical expansion of storage space is not feasible. However, this does not mean that there are no other effective measures to increase warehouse productivity. These include the implementation of automated storage and retrieval systems (AS/RS), which could optimize the use of existing space and improve material handling efficiency. Another option is the deployment of IoT technologies and RFID sensors, which would enable more precise inventory management and minimize the need for external storage.

The literature review can further be enriched through a comprehensive scrutiny of Industry 4.0 technology, comprising real-time observation, AI-governed planning of logistics, and digital twin simulations, which are increasingly involved in modern-day supply chain management.

• Thank you for your comment. The literature review has been expanded to include a comprehensive analysis of Industry 4.0 technologies. The review demonstrates that modern Industry 4.0 technologies, such as IoT, artificial intelligence, and digital twins, have a significant impact on the optimization of material flows in logistics and manufacturing. The application of these technologies enables more precise analysis, faster decision-making, and more efficient supply chain management. Current research focuses on integrating these systems into practice, emphasizing their impact on sustainability and the ecological optimization of transport processes.

 

 Besides, even if the sources mentioned are relevant, there are also some mentioned references that are less up to date or fail to cite current progress in automated material handling systems. The essay also does not evidently state what the specific knowledge gap it attempts to fill since the issue of material flow optimization has already been well researched by earlier studies. More emphasis on how this piece of work serves to fill some gap in the literature—i.e., rebutting industry-specific constraints or propounding a fresh methodological procedure—would render the review more rational.

• Thank you for your comment. This has been added in the Introduction section and also discussed in the Discussion section.

In-depth comments:
Lines 8–26) The abstract is referred to in "modern analytical tools, including visualization techniques and efficiency assessment models" but is not followed with examples. Giving particular examples such as simulation packages or mathematical modelling techniques would serve to establish lucidity.

• Thank you. The abstract has been carefully revised according to the requirements of both reviewers.
  (Lines 13–14) The study is performed on a Veselí nad Lužnicí plant, but why they used this plant is not indicated. Was it because it was inefficient, like in the sector, or due to the fact that data were available? It would make the study more valid if the reason were included.
• Thank you for your comment. This has been added to the Methodology section.

(98–150) Review of literature mentions "material flow optimization" but typically oscillates between synonym but not identical words such as "supply chain optimization," "warehouse efficiency," and "facility layout." More specifically would be clarification of whether such are subtopics under material flow optimization or replaceable topics.

• Thank you. This has been explained at the beginning of the Literature Review section. The literature review explicitly differentiates material flow optimization from broader supply chain management concepts, considering warehouse efficiency and facility layout as integral subtopics of material flow optimization. The discussion on Industry 4.0 technologies, Lean methodologies, and mathematical models provides a comprehensive framework that reflects modern challenges in logistics. This ensures that the study remains directly focused on material flow optimization, distinguishing it from broader logistics strategies.

(Line 165) The process of material flow optimization is depicted by Figure 1 but does not show how a step comes after the subsequent stages. Adding brief explanations or transition words to the text would enable readers to better imagine the sequence of steps.

• Thank you. Figure 1 has been revised and supplemented with supporting steps. Additionally, a detailed description of Figure 1 and the methodology has been added.

(Tables 1–4, Lines 381–411) The tables of cost for forklift, staff, and transport fee use different levels of decimal precision (e.g., some are rounded to two decimals, others to five). Consistency in numerical formatting would enhance clarity and comparison.

• Thank you. This reviewer’s comment has been addressed. The issue was not caused by inconsistent rounding to different decimal places but by differences in the notation of thousands in the English language. In English, a comma is typically used to separate thousands (e.g., 1,000.00 €), while in other languages, including Slovak, a space or a period is used for this purpose (e.g., 1 000,00 € or 1.000,00 €).
• In the revised version, we have ensured consistent numerical formatting throughout the document to maintain clarity and uniformity of the data. This adjustment eliminates any potential ambiguities when comparing different numerical values in the tables.

(626–650) No mention of environmental effects. In the interest of emphasizing optimization of logistics, savings of CO2 due to lower transport lengths or fuel efficiency gains must be measured and considered a second-order gain.

• Thank you for your valuable comment. This has been added to the Discussion section.

(Lines 636–650) It is recommended in the paper that further research in IoT and machine learning for streamlining material flow is prudent, but this is not linked back to the case study. Are these technologies applied to Veselí nad Lužnicí's factory or are they generic recommendations? Creating a real-life context for the innovations would improve the conclusion.

• Thank you. We have incorporated this into the Discussion section.

Best regards

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Accept in present form.

Reviewer 2 Report

Comments and Suggestions for Authors

The Authors improved the paper significantly.