Simulation Study of Dynamic Bus Lane Concept

Round 1

Reviewer 1 Report

The paper presents a simulation study regarding various installation schemes of a bus lane in 4 road segments in Poland. A dynamic bus lane concept (DBL) is compared against a traditional bus lane installation (XBL) scheme and the current situation.

 

Although the paper indeed presents some innovative issues, major restructure is needed in order to have some possibilities for publication. Please find below my main concerns

• I found the calibration process really interesting through the usage of the genetic algorithm. However the travel time differences between the observed and the modeled case, as well as the GEH index, indicate medium convergence levels. This is something that was not expected to happen due to the simplicity of the network and the low volumes at the network. Can you please comment on that?
• No information is given about the number of passengers at the buses. Is that a major criterion for (de)-activation of the DBL? Please commend at the last section of the paper
• No information or comment is given by the authors about the economic/financial side of the scheme. I suppose this is a major criterion for policy makers to be persuaded about the feasibility of the intervention.
• Section 5 needs further development especially at the point of the deactivation and activation of the DBL. How this was coded at VISSIM? Did they authors used softwares’ add on VisVAP or do they implemented something more sophisticated, e.g. through external Matlab scripting. Please refer to a similar study

A. Kampouri, I. Politis, “Optimization of a bus lane with intermittent priority dynamically activated by the road traffic”, 23rd International Transport and Air Pollution Conference, 15-17 May 2019, Thessaloniki, Greece

PDF: http://pol.webpages.auth.gr/wp-content/uploads/2020/10/IC65.pdf

•  I find no reason to give Figure 5(at line 229-230)-please explain better what is the purpose of this. Also Figure 5 appears 2 times at the manuscript - please correct
• One of the major limitation of the paper is the absence of the research objectives. What exists in the literature and what this article wants to add? Please extend the literature with an in depth analysis of the existing work globally and try to identify possible research gaps that this work tries to answer.
• Similar to my previous comment, the paper suffers from a policy recommendation - policy implication section after the result section. Giving just percentage differences between simulation scenarios at given road section in Poland,  does not add anything to the literature.
• Taking about sustainable mobility, one should expect to see that the analysis is covering broader issues an not just travel times at a network. For example, what if the (de) activation rule was based on serving maximum passenger-trips instead of vehicle trips? Or What if the rule was based on environmental criteria such as fuel consumption and/or emissions?      

Author Response

Although the paper indeed presents some innovative issues, major restructure is needed in order to have some possibilities for publication. Please find below my main concerns:

 

I found the calibration process really interesting through the usage of the genetic algorithm. However the travel time differences between the observed and the modeled case, as well as the GEH index, indicate medium convergence levels. This is something that was not expected to happen due to the simplicity of the network and the low volumes at the network. Can you please comment on that?

• The worst value for GEH index among all the sections was obtained for Podkarpacka street. It was a 1300 m long section with 3 intersections with traffic lights. Vehicles on this section were blocked at the last intersection, therefore, despite the low traffic volume, traffic conditions were the worst among all analyzed sections. Therefore, the GEH index was the least favorable, although still below the recommended border value (reference [25]). A paragraph on GEH calculation was added - lines 218-221. 

No information is given about the number of passengers at the buses. Is that a major criterion for (de)-activation of the DBL? Please commend at the last section of the paper

• Bus occupancy is a very important factor in DBL analysis. Observed values are now shown in Table 1 and occupancy is used in the proposed new indicator WATT (lines 300-308, 331). It is proposed to do a sensitivity analysis as part of the future research, varying the bus occupancy (lines 350-352). 

No information or comment is given by the authors about the economic/financial side of the scheme. I suppose this is a major criterion for policy makers to be persuaded about the feasibility of the intervention.

• The economical side was analyzed in the previous paper “Analysis of the economic effectiveness of bus lanes with intermittent priority” Logistyka 6/2014.  The paper presents an economic analysis concerning placing dedicated bus lanes on selected streets in Rzeszow, where bus traffic is moderate. The analysis shows the costs associated with the implementation and maintenance of bus lanes in different alternatives. Developing further the economic analysis methodology is proposed for future research (lines 353-356).

Section 5 needs further development especially at the point of the deactivation and activation of the DBL. How this was coded at VISSIM? Did they authors used softwares’ add on VisVAP or do they implemented something more sophisticated, e.g. through external Matlab scripting. Please refer to a similar study

• In order to control the DBL system, the Vis/Vap software was used. The control logic was described in the previous article “Traffic modelling with dynamic bus lane” . The article was added to references [26]. A paragraph on the control logic has been re-written.

 

65. Kampouri, I. Politis, “Optimization of a bus lane with intermittent priority dynamically activated by the road traffic”, 23rd International Transport and Air Pollution Conference, 15-17 May 2019, Thessaloniki, Greece.PDF: http://pol.webpages.auth.gr/wp-content/uploads/2020/10/IC65.pdf

• The publication is very interesting and it was added to the references.

I find no reason to give Figure 5(at line 229-230)-please explain better what is the purpose of this. Also Figure 5 appears 2 times at the manuscript - please correct

• The paper was again reviewed very carefully and all descriptions have been updated. As a result of these actions the numbering has changed. The correct number for this figure is 6. The figure shows the DBL activation process in Vissim at each stage. Figure 6 descriptions have been also improved and the figure is now clearer

One of the major limitation of the paper is the absence of the research objectives. What exists in the literature and what this article wants to add? Please extend the literature with an in depth analysis of the existing work globally and try to identify possible research gaps that this work tries to answer.

• Research objectives have been added at the end of section 1 (lines 72-78).

Similar to my previous comment, the paper suffers from a policy recommendation - policy implication section after the result section. Giving just percentage differences between simulation scenarios at given road section in Poland,  does not add anything to the literature.

• A new indicator WATT has been proposed - it can be used to assess the feasibility of DBL schemes. A policy recommendation paragraph has been added at the end of the “Conclusions” section (lines 373-377).  

Taking about sustainable mobility, one should expect to see that the analysis is covering broader issues an not just travel times at a network. For example, what if the (de) activation rule was based on serving maximum passenger-trips instead of vehicle trips? Or What if the rule was based on environmental criteria such as fuel consumption and/or emissions? 

• Thank you for these useful suggestions. These aspects are proposed to be considered in future research (lines 350-356).

 

Reviewer 2 Report

Notes for Authors:

- the research topic described in the manuscript is very interesting and innovative.

- in line 62 there is the mention of four selected sections, while only three of them are listed in the brackets below (line 63) - the section at  Podkarpacka Street is missing.

- I do not find a reference to Figure 2 in the text,

- according to the scheme in Figure 1, the detectors are marked as D1 and D2 (respectively approach detector and exit one). But the diagram in Figure 4 uses the expressions “D1 = 0” or “D2 = D1”. I guess in terms of the number of buses registered by the detector. In my opinion, appropriate markings (other than detector marking) should be used in this case.

The above-mentioned comments are mainly editorial and do not affect my high opinion of the publication.

Author Response

Notes for Authors:

- the research topic described in the manuscript is very interesting and innovative.

- in line 62 there is the mention of four selected sections, while only three of them are listed in the brackets below (line 63) - the section at  Podkarpacka Street is missing.

 

• The missing street was added

 

- I do not find a reference to Figure 2 in the text,

 

• The work was again reviewed very carefully and all missing references (also to Figure 2) were added.

 

- according to the scheme in Figure 1, the detectors are marked as D1 and D2 (respectively approach detector and exit one). But the diagram in Figure 4 uses the expressions “D1 = 0” or “D2 = D1”. I guess in terms of the number of buses registered by the detector. In my opinion, appropriate markings (other than detector marking) should be used in this case.

 

• The descriptions in the figure presenting the “DBL control logic” have been changed in accordance with the note.

 

The above-mentioned comments are mainly editorial and do not affect my high opinion of the publication.

Reviewer 3 Report

A research described in the manuscript is simulative and concerns a dynamic bus lane concept. The authors presented a case study of the dynamic bus lane prepared on the basis of real road traffic conditions in one of the cities of southern Poland. The adopted simulation model is correct. The authors obtained results indicating the possibility of a significant reduction in the nuisance of bus lanes for private car users if the concept of a dynamic bus lane is applied. Those are original achievements of the authors. The conclusions of the research are correct.
However, the presented work has some shortcomings too. These are following:
First of all, the publication is written carelessly. There are a lot of typos, missing information. In many places, the authors did not follow the guidelines for authors. One time figure caption is below the figure, the next time - above. This is annoying, and it certainly has an impact on the overall rating of the article. Was it impossible to check the article carefully before submitting?
Some examples:
line 4 - Piotr Olszewsi - line 6 [email protected] - Is the last name surely spelled correctly?
lines 5-7 - Do the authors have affiliation, or maybe are freelancers? University? Department?
line 46 - there is (1) - it should be [1] - use square brackets when referring to resources in the entire manuscript
line 56 - "The..." and what is next?
lines 62-63 - Four streets were mentioned and then only three are listed by name.
line 126 - There is "4.1 application" it should be "4.1 Application".
line 229 - Letters in figure 4 can be seen only partially
line 229 - Figure 5 - Pictures a-d should be zoomed, and the most important details/differences should be indicated by arrows or in a similar way.
Literature " J. M. Viegas, R. Roque , B. Lu i J. Vieira" - What "i" letter stands for?
The authors are requested to check carefully the entire work and to correct all the errors.
The second thig is that the authors referred to 25 resources, but only few of them are from the recent years (2019 and 2020). It is not difficult to find some other papers on a similar topic using e.g. Science Direct. Authors are requested to comment on that, and add some new information, if possible.
In sum, the manuscript might be of interests of Sustainability journal but the corrections listed above are mandatory.

Author Response

A research described in the manuscript is simulative and concerns a dynamic bus lane concept. The authors presented a case study of the dynamic bus lane prepared on the basis of real road traffic conditions in one of the cities of southern Poland. The adopted simulation model is correct. The authors obtained results indicating the possibility of a significant reduction in the nuisance of bus lanes for private car users if the concept of a dynamic bus lane is applied. Those are original achievements of the authors. The conclusions of the research are correct.

However, the presented work has some shortcomings too. These are following:

First of all, the publication is written carelessly. There are a lot of typos, missing information. In many places, the authors did not follow the guidelines for authors. One time figure caption is below the figure, the next time - above. This is annoying, and it certainly has an impact on the overall rating of the article. Was it impossible to check the article carefully before submitting?

Some examples:

line 4 - Piotr Olszewsi - line 6 [email protected] - Is the last name surely spelled correctly?

lines 5-7 - Do the authors have affiliation, or maybe are freelancers? University? Department? 

line 46 - there is (1) - it should be [1] - use square brackets when referring to resources in the entire manuscript

line 56 - "The..." and what is next?

lines 62-63 - Four streets were mentioned and then only three are listed by name.

line 126 - There is "4.1 application" it should be "4.1 Application".

line 229 - Letters in figure 4 can be seen only partially

line 229 - Figure 5 - Pictures a-d should be zoomed, and the most important details/differences should be indicated by arrows or in a similar way.

Literature " J. M. Viegas, R. Roque , B. Lu i J. Vieira" - What "i" letter stands for? 

The authors are requested to check carefully the entire work and to correct all the errors.

 

• All the errors mentioned above have been corrected and the text has been formatted with the correct template.

 

The second thing is that the authors referred to 25 resources, but only few of them are from the recent years (2019 and 2020). It is not difficult to find some other papers on a similar topic using e.g. Science Direct. Authors are requested to comment on that, and add some new information, if possible.

 

• Resources listed in the references have been re-verified. Finally, four articles were changed to newer ones. It was also decided to add two new articles.

 

In sum, the manuscript might be of interests of Sustainability journal but the corrections listed above are mandatory.

Reviewer 4 Report

After reading the manuscript suggested carefully, the manuscript should be improved in an extensive way. The following suggestions could be provided to the authors:

The whole manuscript should be formatted to follow the journal guidelines. For example, the way to cite references is not totally incorrect along with main text, tables, figures and references.

Abstract should be improved in a more extensive way.

Please avoid reference overkill, i.e., do not use more than 3 references per sentence. If you really need to use more, make sure the key idea of each reference is mentioned.

In the introduction, it would strengthen the argument on the methodology if it would be clearly stated what is innovative about this specific methodological development. Also, it requires to mention the objectives of the study in the end of introduction section.

In line with the latter, also balance and articulation of the methodological approach needs to be improved so that the application can be actually demonstrative of the validity of the methodology.

Please improve the quality of figures presented and add more figures that explained in the text. Some texts inside of the figures are not clear enough for the general journal readers.

The authors should analyze the data deeply that should consider the utilization of SPSS statistics tool along with more figures that should give more readability for the general journal readers aforementioned.

The authors have failed to explain the implications of the results. Improve the findings section with critically addressing the applicability of your findings.

The discussion on results is poorly presented. The execution of the proposed methodology is appreciable while the discussion of the obtained results must be well improved highlighting the insights of the research findings and with support from earlier literature. I find many unsupported statements in this section.

Please revise your conclusion part into more details. Basically, you should enhance your contributions, limitations, underscore the scientific value added of your paper, and/or the applicability of your findings/results and future study in this session.

The current references are not adequate in the context of numbers and quality that should be improved with recent and related references together with the publication of the Sustainability.

There are too many incorrect language details in your manuscript (lexical, grammatical and spelling errors, and phrases that do not belong to correct English). Please seek professional language assistance to ensure that language errors are eliminated, and the style of writing becomes more reader-friendly.

Author Response

After reading the manuscript suggested carefully, the manuscript should be improved in an extensive way. The following suggestions could be provided to the authors:

The whole manuscript should be formatted to follow the journal guidelines. For example, the way to cite references is not totally incorrect along with main text, tables, figures and references.

• The work was again reviewed very carefully and the text has been formatted with the correct template.

 

Abstract should be improved in a more extensive way.

• The abstract has been rewritten and improved. It cannot be further extended due to the 200 word limit. 

Please avoid reference overkill, i.e., do not use more than 3 references per sentence. If you really need to use more, make sure the key idea of each reference is mentioned.

• Resources listed in the references have been verified. Maximum 3 references were used in one sentence.

 

In the introduction, it would strengthen the argument on the methodology if it would be clearly stated what is innovative about this specific methodological development. Also, it requires to mention the objectives of the study in the end of introduction section.

• Research objectives have been added at the end of section 1 (lines 72-78).

In line with the latter, also balance and articulation of the methodological approach needs to be improved so that the application can be actually demonstrative of the validity of the methodology.

• The article has been revised with this suggestion in mind. 

Please improve the quality of figures presented and add more figures that explained in the text. Some texts inside of the figures are not clear enough for the general journal readers.

• The paper was again reviewed very carefully. Figure description and quality has been also improved.

The authors should analyze the data deeply that should consider the utilization of SPSS statistics tool along with more figures that should give more readability for the general journal readers aforementioned.

• According to the suggestion above, a new Figure 4 was added which shows the comparison of observed and model travel time statistics. The diagram shows both average values as well as standard deviations (mean +/- one standard deviation range). We hope that this will increase readability.

The authors have failed to explain the implications of the results. Improve the findings section with critically addressing the applicability of your findings.

• Implications of the research have been discussed in the Discussion section as well as at the end of Conclusions section (lines 373-377).

The discussion on results is poorly presented. The execution of the proposed methodology is appreciable while the discussion of the obtained results must be well improved highlighting the insights of the research findings and with support from earlier literature. I find many unsupported statements in this section.

• A new discussion section (7) has been added (lines 319-356). It highlights the insights, research findings of the study and their applicability. 

Please revise your conclusion part into more details. Basically, you should enhance your contributions, limitations, underscore the scientific value added of your paper, and/or the applicability of your findings/results and future study in this session.

• Conclusions have been revised. Limitations of the proposed methodology, applicability and future research were included in the Discussion section (lines 343-356).

The current references are not adequate in the context of numbers and quality that should be improved with recent and related references together with the publication of the Sustainability.

• The references have been formatted according to the correct template. New references were added, including 2 relevant articles in Sustainability.

There are too many incorrect language details in your manuscript (lexical, grammatical and spelling errors, and phrases that do not belong to correct English). Please seek professional language assistance to ensure that language errors are eliminated, and the style of writing becomes more reader-friendly.

• The manuscript has been revised in order to correct and eliminate the language errors.

 

Round 2

Reviewer 1 Report

I was happy to see that the authors managed to clearly respond to the majority of my comments. 

In its current form, the paper is suitable for publication, since the second version is much more enriched compared to the first version

Author Response

Thank you for this comment.

Reviewer 4 Report

First of all, I appreciate to the authors for making efforts to carry out the changes by the referees. I think the authors did major changes in clarifying the queries. However, the manuscript has still some flaws that can’t be improved during the first revision. The following suggestions are provided to the authors.

Although I believe that the authors dealt with some of the remarks and criticisms the referees made, I still do not feel that this paper contributes sufficiently. Particularly, in section of the introduction, it still needs to be improved with more recent information that could strengthen the argument on the methodology. In the same context, the quantity and quality of references still are not enough to support the objectives of this study.

Also, there are too many incorrect language details in your manuscript (lexical, grammatical and spelling errors, and phrases that do not belong to correct English). Please seek professional language assistance to ensure that language errors are eliminated, and the style of writing becomes more reader-friendly.

In the section of results, the authors are either overinterpreting their results, or they are not making it clear enough that the results are valid. If they are overinterpreting, then they need to be more honest with the reader. If your presentation is not clear enough, then you need to work with a professional language editor to tighten your grammatical and logical argumentation.

Author Response

First of all, I appreciate to the authors for making efforts to carry out the changes by the referees. I think the authors did major changes in clarifying the queries. However, the manuscript has still some flaws that can’t be improved during the first revision. The following suggestions are provided to the authors.

Although I believe that the authors dealt with some of the remarks and criticisms the referees made, I still do not feel that this paper contributes sufficiently. Particularly, in section of the introduction, it still needs to be improved with more recent information that could strengthen the argument on the methodology. In the same context, the quantity and quality of references still are not enough to support the objectives of this study.

• The references support the article with 31 technical publications and manuals. There are six new positions in the references which support the main objectives.

Also, there are too many incorrect language details in your manuscript (lexical, grammatical and spelling errors, and phrases that do not belong to correct English). Please seek professional language assistance to ensure that language errors are eliminated, and the style of writing becomes more reader-friendly.

• The manuscript has been revised to eliminate spelling and language errors. Over 210 corrections were made. In several paragraphs the style has been changed and additional explanations provided to make the text more reader-friendly. 

In the section of results, the authors are either overinterpreting their results, or they are not making it clear enough that the results are valid. If they are overinterpreting, then they need to be more honest with the reader. If your presentation is not clear enough, then you need to work with a professional language editor to tighten your grammatical and logical argumentation.

• It is rather difficult to understand what exactly is meant by “overinterpretation of results”? The results are reported as results of traffic simulations and as such should not be generalized and be treated by the readers with some caution. The sentence “As the results presented are based on a limited number of traffic simulation runs, the conclusions should be viewed with some caution.” was added (line 359) to make clear. The words “According to traffic simulation” were also added in line 376 to make it clear that we are not talking about empirical observations.
  Furthermore, only four sites were examined and analysed. It was made clear that conclusions are drawn based on these four cases and should not be generalized. The words: “Based on the cases analyzed” were added in the summary (line 386).