Metadata-Based Systematic Review: Mapping Knowledge Structures of the Marine Shipping Field

# Metadata-Based Systematic Review: Mapping Knowledge Structures of the Marine Shipping Field
### Thierry Warin, PhD

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# Outline

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### Outline

1. Methodology

2. Descriptive statistics

3. Conceptual structures

4. Social structures

5. Conclusion

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class: inverse, center, middle

# 1. Methodology

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### 1. Methodology

> Research Question: When have we started to talk about the northern sea route?

- Metadata-Based systematic literature review:

- What is it?

- Why can it be useful?

- Next steps?

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### 1. Methodology

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### 1. Methodology

Analytics and Graphs for three different level metrics:

- Sources (local and global citations)

- Authors

- Documents

Three structures of Knowledge (K-structures):

- **Conceptual Structures**

- Intellectual Structures

- **Social Structures**

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### 1. Methodology

Aria, M., Misuraca, M., & Spano, M. (2020). Mapping the evolution of social research and data science on 30 years of Social Indicators Research. Social Indicators Research, 1-29, DOI: 10.1007/s11205-020-02281-3.

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class: inverse, center, middle

# 2. Descriptive Statistics

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###  2. Descriptive Statistics

In Web of Science, in topics

- MARINE SHIPPING

- NORTHERN SEA ROUTE

- NORTHWEST PASSAGE

- ARCTIC SHIPPING

A total of 14,665 references

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### Descriptive Statistics

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<table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Main information</caption>
 <thead>
  <tr>
   <th style="text-align:left;"> Description </th>
   <th style="text-align:left;"> Overall Time Period </th>
   <th style="text-align:left;"> 2020 </th>
   <th style="text-align:left;"> 2019 </th>
   <th style="text-align:left;"> 2018 </th>
   <th style="text-align:left;"> 2017 </th>
   <th style="text-align:left;"> 2016 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> Timespan </td>
   <td style="text-align:left;"> 1950:2020 </td>
   <td style="text-align:left;"> 2020:2020 </td>
   <td style="text-align:left;"> 2019:2019 </td>
   <td style="text-align:left;"> 2018:2018 </td>
   <td style="text-align:left;"> 2017:2017 </td>
   <td style="text-align:left;"> 2016:2016 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Sources (Journals, Books, etc) </td>
   <td style="text-align:left;"> 4288 </td>
   <td style="text-align:left;"> 458 </td>
   <td style="text-align:left;"> 613 </td>
   <td style="text-align:left;"> 632 </td>
   <td style="text-align:left;"> 557 </td>
   <td style="text-align:left;"> 581 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Documents </td>
   <td style="text-align:left;"> 14665 </td>
   <td style="text-align:left;"> 1044 </td>
   <td style="text-align:left;"> 1420 </td>
   <td style="text-align:left;"> 1394 </td>
   <td style="text-align:left;"> 1118 </td>
   <td style="text-align:left;"> 1128 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Average years from publication </td>
   <td style="text-align:left;"> 9.43 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> 5 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Average citations per documents </td>
   <td style="text-align:left;"> 14.36 </td>
   <td style="text-align:left;"> 0.7031 </td>
   <td style="text-align:left;"> 2.496 </td>
   <td style="text-align:left;"> 5.169 </td>
   <td style="text-align:left;"> 6.911 </td>
   <td style="text-align:left;"> 9.493 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Average citations per year per doc </td>
   <td style="text-align:left;"> 1.398 </td>
   <td style="text-align:left;"> 0.3515 </td>
   <td style="text-align:left;"> 0.8319 </td>
   <td style="text-align:left;"> 1.292 </td>
   <td style="text-align:left;"> 1.382 </td>
   <td style="text-align:left;"> 1.582 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> References </td>
   <td style="text-align:left;"> 339232 </td>
   <td style="text-align:left;"> 42524 </td>
   <td style="text-align:left;"> 50242 </td>
   <td style="text-align:left;"> 44783 </td>
   <td style="text-align:left;"> 35667 </td>
   <td style="text-align:left;"> 33832 </td>
  </tr>
</tbody>
</table>

]

<div style="border: 1px solid #ddd; padding: 0px; overflow-y: scroll; height:400px; overflow-x: scroll; width:100%; "><table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Document Type</caption>
 <thead>
  <tr>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Description </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Overall Time Period </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> 2020 </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> 2019 </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> 2018 </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> 2017 </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> 2016 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> Art Exhibit Review </td>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Article </td>
   <td style="text-align:left;"> 9248 </td>
   <td style="text-align:left;"> 930 </td>
   <td style="text-align:left;"> 1068 </td>
   <td style="text-align:left;"> 984 </td>
   <td style="text-align:left;"> 780 </td>
   <td style="text-align:left;"> 768 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Article; Book Chapter </td>
   <td style="text-align:left;"> 6 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Article; Data Paper </td>
   <td style="text-align:left;"> 11 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Article; Early Access </td>
   <td style="text-align:left;"> 86 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Article; Proceedings Paper </td>
   <td style="text-align:left;"> 467 </td>
   <td style="text-align:left;"> 16 </td>
   <td style="text-align:left;"> 20 </td>
   <td style="text-align:left;"> 29 </td>
   <td style="text-align:left;"> 25 </td>
   <td style="text-align:left;"> 33 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Biographical-Item </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Book Review </td>
   <td style="text-align:left;"> 138 </td>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 4 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Chronology </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Correction </td>
   <td style="text-align:left;"> 6 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Editorial Material </td>
   <td style="text-align:left;"> 77 </td>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> 5 </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 7 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Letter </td>
   <td style="text-align:left;"> 10 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Meeting Abstract </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> News Item </td>
   <td style="text-align:left;"> 25 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 3 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 2 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Note </td>
   <td style="text-align:left;"> 7 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Poetry </td>
   <td style="text-align:left;"> 5 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Proceedings Paper </td>
   <td style="text-align:left;"> 3450 </td>
   <td style="text-align:left;"> 38 </td>
   <td style="text-align:left;"> 242 </td>
   <td style="text-align:left;"> 334 </td>
   <td style="text-align:left;"> 279 </td>
   <td style="text-align:left;"> 273 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Proceedings Paper; Retracted Publication </td>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Record Review </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Reprint </td>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Review </td>
   <td style="text-align:left;"> 469 </td>
   <td style="text-align:left;"> 52 </td>
   <td style="text-align:left;"> 70 </td>
   <td style="text-align:left;"> 34 </td>
   <td style="text-align:left;"> 31 </td>
   <td style="text-align:left;"> 37 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Review; Book Chapter </td>
   <td style="text-align:left;"> 10 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 4 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Review; Early Access </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Software Review </td>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
   <td style="text-align:left;"> 0 </td>
  </tr>
</tbody>
</table></div>

]

<table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Document Content and Authors</caption>
 <thead>
  <tr>
   <th style="text-align:left;">   </th>
   <th style="text-align:left;"> Description </th>
   <th style="text-align:left;"> Overall Time Period </th>
   <th style="text-align:left;"> 2020 </th>
   <th style="text-align:left;"> 2019 </th>
   <th style="text-align:left;"> 2018 </th>
   <th style="text-align:left;"> 2017 </th>
   <th style="text-align:left;"> 2016 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> 1 </td>
   <td style="text-align:left;"> Keywords Plus (ID) </td>
   <td style="text-align:left;"> 16252 </td>
   <td style="text-align:left;"> 2830 </td>
   <td style="text-align:left;"> 3271 </td>
   <td style="text-align:left;"> 3206 </td>
   <td style="text-align:left;"> 2687 </td>
   <td style="text-align:left;"> 2561 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> 2 </td>
   <td style="text-align:left;"> Author's Keywords (DE) </td>
   <td style="text-align:left;"> 28699 </td>
   <td style="text-align:left;"> 4461 </td>
   <td style="text-align:left;"> 5262 </td>
   <td style="text-align:left;"> 4646 </td>
   <td style="text-align:left;"> 3834 </td>
   <td style="text-align:left;"> 3770 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> Authors </td>
   <td style="text-align:left;"> 33916 </td>
   <td style="text-align:left;"> 3558 </td>
   <td style="text-align:left;"> 4750 </td>
   <td style="text-align:left;"> 4398 </td>
   <td style="text-align:left;"> 3515 </td>
   <td style="text-align:left;"> 3608 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> 5 </td>
   <td style="text-align:left;"> Author Appearances </td>
   <td style="text-align:left;"> 54738 </td>
   <td style="text-align:left;"> 4570 </td>
   <td style="text-align:left;"> 6172 </td>
   <td style="text-align:left;"> 5665 </td>
   <td style="text-align:left;"> 4328 </td>
   <td style="text-align:left;"> 4312 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> 6 </td>
   <td style="text-align:left;"> Authors of single-authored documents </td>
   <td style="text-align:left;"> 1734 </td>
   <td style="text-align:left;"> 98 </td>
   <td style="text-align:left;"> 135 </td>
   <td style="text-align:left;"> 119 </td>
   <td style="text-align:left;"> 107 </td>
   <td style="text-align:left;"> 124 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> 7 </td>
   <td style="text-align:left;"> Authors of multi-authored documents </td>
   <td style="text-align:left;"> 32182 </td>
   <td style="text-align:left;"> 3460 </td>
   <td style="text-align:left;"> 4615 </td>
   <td style="text-align:left;"> 4279 </td>
   <td style="text-align:left;"> 3408 </td>
   <td style="text-align:left;"> 3484 </td>
  </tr>
</tbody>
</table>
       
]

<table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Authors Collaboration</caption>
 <thead>
  <tr>
   <th style="text-align:left;"> Description </th>
   <th style="text-align:left;"> Overall Time Period </th>
   <th style="text-align:left;"> 2020 </th>
   <th style="text-align:left;"> 2019 </th>
   <th style="text-align:left;"> 2018 </th>
   <th style="text-align:left;"> 2017 </th>
   <th style="text-align:left;"> 2016 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> Single-authored documents </td>
   <td style="text-align:left;"> 2219 </td>
   <td style="text-align:left;"> 110 </td>
   <td style="text-align:left;"> 150 </td>
   <td style="text-align:left;"> 139 </td>
   <td style="text-align:left;"> 114 </td>
   <td style="text-align:left;"> 143 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Documents per Author </td>
   <td style="text-align:left;"> 0.432 </td>
   <td style="text-align:left;"> 0.293 </td>
   <td style="text-align:left;"> 0.299 </td>
   <td style="text-align:left;"> 0.317 </td>
   <td style="text-align:left;"> 0.318 </td>
   <td style="text-align:left;"> 0.313 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Authors per Document </td>
   <td style="text-align:left;"> 2.31 </td>
   <td style="text-align:left;"> 3.41 </td>
   <td style="text-align:left;"> 3.35 </td>
   <td style="text-align:left;"> 3.15 </td>
   <td style="text-align:left;"> 3.14 </td>
   <td style="text-align:left;"> 3.2 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Co-Authors per Documents </td>
   <td style="text-align:left;"> 3.73 </td>
   <td style="text-align:left;"> 4.38 </td>
   <td style="text-align:left;"> 4.35 </td>
   <td style="text-align:left;"> 4.06 </td>
   <td style="text-align:left;"> 3.87 </td>
   <td style="text-align:left;"> 3.82 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Collaboration Index </td>
   <td style="text-align:left;"> 2.59 </td>
   <td style="text-align:left;"> 3.7 </td>
   <td style="text-align:left;"> 3.63 </td>
   <td style="text-align:left;"> 3.41 </td>
   <td style="text-align:left;"> 3.39 </td>
   <td style="text-align:left;"> 3.54 </td>
  </tr>
</tbody>
</table>

]

---
class: inverse, middle, center

# 3. Conceptual structures

---
class: center, middle

# Keywords

---

<div style="border: 1px solid #ddd; padding: 0px; overflow-y: scroll; height:400px; overflow-x: scroll; width:100%; "><table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Most Relevant Keywords</caption>
 <thead>
  <tr>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Author Keywords (DE) </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Articles </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Keywords-Plus (ID) </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Articles </th>
  </tr>
 </thead>
<tbody>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>Overall Time Period</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Arctic </td>
   <td style="text-align:left;"> 392 </td>
   <td style="text-align:left;"> Model </td>
   <td style="text-align:left;"> 563 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine </td>
   <td style="text-align:left;"> 318 </td>
   <td style="text-align:left;"> Sea </td>
   <td style="text-align:left;"> 434 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Shipping </td>
   <td style="text-align:left;"> 294 </td>
   <td style="text-align:left;"> Marine </td>
   <td style="text-align:left;"> 425 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Ship </td>
   <td style="text-align:left;"> 236 </td>
   <td style="text-align:left;"> Ocean </td>
   <td style="text-align:left;"> 369 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Climate Change </td>
   <td style="text-align:left;"> 180 </td>
   <td style="text-align:left;"> Ships </td>
   <td style="text-align:left;"> 362 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2021</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine Vehicles </td>
   <td style="text-align:left;"> 68 </td>
   <td style="text-align:left;"> Model </td>
   <td style="text-align:left;"> 75 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Shipping </td>
   <td style="text-align:left;"> 25 </td>
   <td style="text-align:left;"> Management </td>
   <td style="text-align:left;"> 51 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine </td>
   <td style="text-align:left;"> 23 </td>
   <td style="text-align:left;"> Ships </td>
   <td style="text-align:left;"> 46 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Arctic </td>
   <td style="text-align:left;"> 22 </td>
   <td style="text-align:left;"> Design </td>
   <td style="text-align:left;"> 44 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Ship </td>
   <td style="text-align:left;"> 18 </td>
   <td style="text-align:left;"> Performance </td>
   <td style="text-align:left;"> 42 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2020</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Arctic </td>
   <td style="text-align:left;"> 67 </td>
   <td style="text-align:left;"> Model </td>
   <td style="text-align:left;"> 63 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine </td>
   <td style="text-align:left;"> 46 </td>
   <td style="text-align:left;"> Marine </td>
   <td style="text-align:left;"> 50 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Shipping </td>
   <td style="text-align:left;"> 31 </td>
   <td style="text-align:left;"> Design </td>
   <td style="text-align:left;"> 48 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Ship </td>
   <td style="text-align:left;"> 30 </td>
   <td style="text-align:left;"> Sea </td>
   <td style="text-align:left;"> 47 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine Vehicles </td>
   <td style="text-align:left;"> 26 </td>
   <td style="text-align:left;"> Emissions </td>
   <td style="text-align:left;"> 46 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2019</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Arctic </td>
   <td style="text-align:left;"> 51 </td>
   <td style="text-align:left;"> Model </td>
   <td style="text-align:left;"> 75 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Shipping </td>
   <td style="text-align:left;"> 50 </td>
   <td style="text-align:left;"> Sea </td>
   <td style="text-align:left;"> 60 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine </td>
   <td style="text-align:left;"> 40 </td>
   <td style="text-align:left;"> Marine </td>
   <td style="text-align:left;"> 58 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Ship </td>
   <td style="text-align:left;"> 25 </td>
   <td style="text-align:left;"> Ships </td>
   <td style="text-align:left;"> 47 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Northern Sea Route </td>
   <td style="text-align:left;"> 22 </td>
   <td style="text-align:left;"> Design </td>
   <td style="text-align:left;"> 45 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2018</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Arctic </td>
   <td style="text-align:left;"> 40 </td>
   <td style="text-align:left;"> Model </td>
   <td style="text-align:left;"> 45 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Climate Change </td>
   <td style="text-align:left;"> 25 </td>
   <td style="text-align:left;"> Sea </td>
   <td style="text-align:left;"> 37 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Ship </td>
   <td style="text-align:left;"> 24 </td>
   <td style="text-align:left;"> Marine </td>
   <td style="text-align:left;"> 35 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Shipping </td>
   <td style="text-align:left;"> 22 </td>
   <td style="text-align:left;"> Variability </td>
   <td style="text-align:left;"> 35 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Northern Sea Route </td>
   <td style="text-align:left;"> 19 </td>
   <td style="text-align:left;"> Design </td>
   <td style="text-align:left;"> 32 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2017</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Arctic </td>
   <td style="text-align:left;"> 50 </td>
   <td style="text-align:left;"> Model </td>
   <td style="text-align:left;"> 45 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Shipping </td>
   <td style="text-align:left;"> 40 </td>
   <td style="text-align:left;"> Marine </td>
   <td style="text-align:left;"> 38 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Marine </td>
   <td style="text-align:left;"> 35 </td>
   <td style="text-align:left;"> Climate-Change </td>
   <td style="text-align:left;"> 34 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Ship </td>
   <td style="text-align:left;"> 23 </td>
   <td style="text-align:left;"> Sea </td>
   <td style="text-align:left;"> 33 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Sea Ice </td>
   <td style="text-align:left;"> 22 </td>
   <td style="text-align:left;"> Ship </td>
   <td style="text-align:left;"> 31 </td>
  </tr>
</tbody>
</table></div>

]

]

---
class: center, middle

# Keywords' co-occurrences

---

### Keyword co-occurrences networks

- Co-word networks show the conceptual structure, that uncovers links between concepts through term co-occurences.

- Conceptual structure is often used to understand the topics covered by scholars (so-called research front) and identify what are the most important and the most recent issues.

- Dividing the whole timespan in different timeslices and comparing the conceptual structures is useful to analyze the evolution of topics over time.

---

]

]

]

]

]

]

<table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption></caption>
 <thead>
  <tr>
   <th style="text-align:left;"> Statistics </th>
   <th style="text-align:right;"> Overall Time Period </th>
   <th style="text-align:right;"> 2020 </th>
   <th style="text-align:right;"> 2019 </th>
   <th style="text-align:right;"> 2018 </th>
   <th style="text-align:right;"> 2017 </th>
   <th style="text-align:right;"> 2016 </th>
  </tr>
 </thead>
<tbody>
  <tr>
   <td style="text-align:left;"> Size </td>
   <td style="text-align:right;"> 16258.000 </td>
   <td style="text-align:right;"> 2831.000 </td>
   <td style="text-align:right;"> 3272.000 </td>
   <td style="text-align:right;"> 3207.000 </td>
   <td style="text-align:right;"> 2687.000 </td>
   <td style="text-align:right;"> 2561.000 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Density </td>
   <td style="text-align:right;"> 0.001 </td>
   <td style="text-align:right;"> 0.005 </td>
   <td style="text-align:right;"> 0.004 </td>
   <td style="text-align:right;"> 0.004 </td>
   <td style="text-align:right;"> 0.005 </td>
   <td style="text-align:right;"> 0.005 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Transitivity </td>
   <td style="text-align:right;"> 0.095 </td>
   <td style="text-align:right;"> 0.229 </td>
   <td style="text-align:right;"> 0.218 </td>
   <td style="text-align:right;"> 0.222 </td>
   <td style="text-align:right;"> 0.273 </td>
   <td style="text-align:right;"> 0.274 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Diameter </td>
   <td style="text-align:right;"> 7.000 </td>
   <td style="text-align:right;"> 6.000 </td>
   <td style="text-align:right;"> 7.000 </td>
   <td style="text-align:right;"> 7.000 </td>
   <td style="text-align:right;"> 8.000 </td>
   <td style="text-align:right;"> 10.000 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Degree Centralization </td>
   <td style="text-align:right;"> 0.105 </td>
   <td style="text-align:right;"> 0.099 </td>
   <td style="text-align:right;"> 0.084 </td>
   <td style="text-align:right;"> 0.102 </td>
   <td style="text-align:right;"> 0.078 </td>
   <td style="text-align:right;"> 0.077 </td>
  </tr>
  <tr>
   <td style="text-align:left;"> Average path length </td>
   <td style="text-align:right;"> 3.026 </td>
   <td style="text-align:right;"> 3.216 </td>
   <td style="text-align:right;"> 3.265 </td>
   <td style="text-align:right;"> 3.259 </td>
   <td style="text-align:right;"> 3.380 </td>
   <td style="text-align:right;"> 3.393 </td>
  </tr>
</tbody>
</table>

]

---
class: middle, center

# Topic modelling

---

]

]

]

]

]

]

---

# Synthesis: authors, keywords, journals

---

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]

---

# 4. Social Structures

---
class: center, middle

# Authors' collaboration networks

---

]

]

]

]

]

]

---
class: center, middle

# Journals' (Source) co-citation analyses

---

]

]

]

]

]

]

---
class: center, middle

# Universities' collaboration networks

---

]

]

]

]

]

]

---
class: center, middle

# Countries' collaborations

---

<div style="border: 1px solid #ddd; padding: 0px; overflow-y: scroll; height:400px; overflow-x: scroll; width:100%; "><table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Corresponding author's countries</caption>
 <thead>
  <tr>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Country </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Articles </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Freq </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> SCP </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> MCP </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> MCP_Ratio </th>
  </tr>
 </thead>
<tbody>
  <tr grouplength="5"><td colspan="6" style="border-bottom: 0;"><strong>Overall Time Period</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United States </td>
   <td style="text-align:left;"> 2415 </td>
   <td style="text-align:left;"> 0.1781 </td>
   <td style="text-align:left;"> 1884 </td>
   <td style="text-align:left;"> 531 </td>
   <td style="text-align:left;"> 0.2199 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> China </td>
   <td style="text-align:left;"> 2109 </td>
   <td style="text-align:left;"> 0.1555 </td>
   <td style="text-align:left;"> 1753 </td>
   <td style="text-align:left;"> 356 </td>
   <td style="text-align:left;"> 0.1688 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United Kingdom </td>
   <td style="text-align:left;"> 873 </td>
   <td style="text-align:left;"> 0.0644 </td>
   <td style="text-align:left;"> 598 </td>
   <td style="text-align:left;"> 275 </td>
   <td style="text-align:left;"> 0.3150 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Canada </td>
   <td style="text-align:left;"> 826 </td>
   <td style="text-align:left;"> 0.0609 </td>
   <td style="text-align:left;"> 606 </td>
   <td style="text-align:left;"> 220 </td>
   <td style="text-align:left;"> 0.2663 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Norway </td>
   <td style="text-align:left;"> 661 </td>
   <td style="text-align:left;"> 0.0487 </td>
   <td style="text-align:left;"> 447 </td>
   <td style="text-align:left;"> 214 </td>
   <td style="text-align:left;"> 0.3238 </td>
  </tr>
  <tr grouplength="5"><td colspan="6" style="border-bottom: 0;"><strong>2020</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> China </td>
   <td style="text-align:left;"> 297 </td>
   <td style="text-align:left;"> 0.2859 </td>
   <td style="text-align:left;"> 223 </td>
   <td style="text-align:left;"> 74 </td>
   <td style="text-align:left;"> 0.249 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United States </td>
   <td style="text-align:left;"> 88 </td>
   <td style="text-align:left;"> 0.0847 </td>
   <td style="text-align:left;"> 62 </td>
   <td style="text-align:left;"> 26 </td>
   <td style="text-align:left;"> 0.295 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United Kingdom </td>
   <td style="text-align:left;"> 52 </td>
   <td style="text-align:left;"> 0.0500 </td>
   <td style="text-align:left;"> 28 </td>
   <td style="text-align:left;"> 24 </td>
   <td style="text-align:left;"> 0.462 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Canada </td>
   <td style="text-align:left;"> 50 </td>
   <td style="text-align:left;"> 0.0481 </td>
   <td style="text-align:left;"> 30 </td>
   <td style="text-align:left;"> 20 </td>
   <td style="text-align:left;"> 0.400 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Russia </td>
   <td style="text-align:left;"> 45 </td>
   <td style="text-align:left;"> 0.0433 </td>
   <td style="text-align:left;"> 40 </td>
   <td style="text-align:left;"> 5 </td>
   <td style="text-align:left;"> 0.111 </td>
  </tr>
  <tr grouplength="5"><td colspan="6" style="border-bottom: 0;"><strong>2019</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> China </td>
   <td style="text-align:left;"> 336 </td>
   <td style="text-align:left;"> 0.2381 </td>
   <td style="text-align:left;"> 272 </td>
   <td style="text-align:left;"> 64 </td>
   <td style="text-align:left;"> 0.1905 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United States </td>
   <td style="text-align:left;"> 161 </td>
   <td style="text-align:left;"> 0.1141 </td>
   <td style="text-align:left;"> 117 </td>
   <td style="text-align:left;"> 44 </td>
   <td style="text-align:left;"> 0.2733 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Russia </td>
   <td style="text-align:left;"> 117 </td>
   <td style="text-align:left;"> 0.0829 </td>
   <td style="text-align:left;"> 107 </td>
   <td style="text-align:left;"> 10 </td>
   <td style="text-align:left;"> 0.0855 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Canada </td>
   <td style="text-align:left;"> 66 </td>
   <td style="text-align:left;"> 0.0468 </td>
   <td style="text-align:left;"> 48 </td>
   <td style="text-align:left;"> 18 </td>
   <td style="text-align:left;"> 0.2727 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United Kingdom </td>
   <td style="text-align:left;"> 65 </td>
   <td style="text-align:left;"> 0.0461 </td>
   <td style="text-align:left;"> 42 </td>
   <td style="text-align:left;"> 23 </td>
   <td style="text-align:left;"> 0.3538 </td>
  </tr>
  <tr grouplength="5"><td colspan="6" style="border-bottom: 0;"><strong>2018</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> China </td>
   <td style="text-align:left;"> 252 </td>
   <td style="text-align:left;"> 0.1821 </td>
   <td style="text-align:left;"> 204 </td>
   <td style="text-align:left;"> 48 </td>
   <td style="text-align:left;"> 0.1905 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United States </td>
   <td style="text-align:left;"> 161 </td>
   <td style="text-align:left;"> 0.1163 </td>
   <td style="text-align:left;"> 112 </td>
   <td style="text-align:left;"> 49 </td>
   <td style="text-align:left;"> 0.3043 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Russia </td>
   <td style="text-align:left;"> 105 </td>
   <td style="text-align:left;"> 0.0759 </td>
   <td style="text-align:left;"> 101 </td>
   <td style="text-align:left;"> 4 </td>
   <td style="text-align:left;"> 0.0381 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Korea </td>
   <td style="text-align:left;"> 74 </td>
   <td style="text-align:left;"> 0.0535 </td>
   <td style="text-align:left;"> 60 </td>
   <td style="text-align:left;"> 14 </td>
   <td style="text-align:left;"> 0.1892 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United Kingdom </td>
   <td style="text-align:left;"> 71 </td>
   <td style="text-align:left;"> 0.0513 </td>
   <td style="text-align:left;"> 39 </td>
   <td style="text-align:left;"> 32 </td>
   <td style="text-align:left;"> 0.4507 </td>
  </tr>
  <tr grouplength="5"><td colspan="6" style="border-bottom: 0;"><strong>2017</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> China </td>
   <td style="text-align:left;"> 203 </td>
   <td style="text-align:left;"> 0.1830 </td>
   <td style="text-align:left;"> 170 </td>
   <td style="text-align:left;"> 33 </td>
   <td style="text-align:left;"> 0.1626 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United States </td>
   <td style="text-align:left;"> 146 </td>
   <td style="text-align:left;"> 0.1317 </td>
   <td style="text-align:left;"> 99 </td>
   <td style="text-align:left;"> 47 </td>
   <td style="text-align:left;"> 0.3219 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Russia </td>
   <td style="text-align:left;"> 76 </td>
   <td style="text-align:left;"> 0.0685 </td>
   <td style="text-align:left;"> 70 </td>
   <td style="text-align:left;"> 6 </td>
   <td style="text-align:left;"> 0.0789 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Norway </td>
   <td style="text-align:left;"> 72 </td>
   <td style="text-align:left;"> 0.0649 </td>
   <td style="text-align:left;"> 49 </td>
   <td style="text-align:left;"> 23 </td>
   <td style="text-align:left;"> 0.3194 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United Kingdom </td>
   <td style="text-align:left;"> 68 </td>
   <td style="text-align:left;"> 0.0613 </td>
   <td style="text-align:left;"> 26 </td>
   <td style="text-align:left;"> 42 </td>
   <td style="text-align:left;"> 0.6176 </td>
  </tr>
  <tr grouplength="5"><td colspan="6" style="border-bottom: 0;"><strong>2016</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> China </td>
   <td style="text-align:left;"> 153 </td>
   <td style="text-align:left;"> 0.1371 </td>
   <td style="text-align:left;"> 132 </td>
   <td style="text-align:left;"> 21 </td>
   <td style="text-align:left;"> 0.1373 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United States </td>
   <td style="text-align:left;"> 153 </td>
   <td style="text-align:left;"> 0.1371 </td>
   <td style="text-align:left;"> 115 </td>
   <td style="text-align:left;"> 38 </td>
   <td style="text-align:left;"> 0.2484 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Canada </td>
   <td style="text-align:left;"> 71 </td>
   <td style="text-align:left;"> 0.0636 </td>
   <td style="text-align:left;"> 46 </td>
   <td style="text-align:left;"> 25 </td>
   <td style="text-align:left;"> 0.3521 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Russia </td>
   <td style="text-align:left;"> 66 </td>
   <td style="text-align:left;"> 0.0591 </td>
   <td style="text-align:left;"> 60 </td>
   <td style="text-align:left;"> 6 </td>
   <td style="text-align:left;"> 0.0909 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> United Kingdom </td>
   <td style="text-align:left;"> 64 </td>
   <td style="text-align:left;"> 0.0573 </td>
   <td style="text-align:left;"> 47 </td>
   <td style="text-align:left;"> 17 </td>
   <td style="text-align:left;"> 0.2656 </td>
  </tr>
</tbody>
</table></div>

]

]

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class: center, middle

# Countries' collaboration networks

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]

]

]

]

]

]

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# 8. Conclusion

---

### 8. Conclusion

- Metadata systematic review: What is it?

- Why can it be useful?

- Next steps?

- Submission this summer: Marine Policy or Maritime Economics & Logistics

---

# Appendix 1. Intellectual Structures

---

### Articles citations

Citation analysis is one of the main classic techniques in bibliometrics.

It shows the structure of a specific field through the linkages between nodes (e.g. authors, papers, journal), while the edges can be differently interpreted depending on the network type, that are namely co-citation, direct citation, bibliographic coupling.

---

### Articles

<div style="border: 1px solid #ddd; padding: 0px; overflow-y: scroll; height:400px; overflow-x: scroll; width:100%; "><table class=" lightable-classic" style='font-family: "Arial Narrow", "Source Sans Pro", sans-serif; margin-left: auto; margin-right: auto;'>
<caption>Most Cited Manuscripts</caption>
 <thead>
  <tr>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Article </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Total citations </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> Total citations per year </th>
   <th style="text-align:left;position: sticky; top:0; background-color: #FFFFFF;"> NTC </th>
  </tr>
 </thead>
<tbody>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>Overall Time Period</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Smith Whf, 1997, Science </td>
   <td style="text-align:left;"> 2898 </td>
   <td style="text-align:left;"> 115.9 </td>
   <td style="text-align:left;"> 68.2 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Kulmala M, 2004, J Aerosol Sci </td>
   <td style="text-align:left;"> 1397 </td>
   <td style="text-align:left;"> 77.6 </td>
   <td style="text-align:left;"> 35.0 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Sandwell Dt, 1997, J Geophys Res -Solid Earth </td>
   <td style="text-align:left;"> 1293 </td>
   <td style="text-align:left;"> 51.7 </td>
   <td style="text-align:left;"> 30.4 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Yebra Dm, 2004, Prog Org Coat </td>
   <td style="text-align:left;"> 1197 </td>
   <td style="text-align:left;"> 66.5 </td>
   <td style="text-align:left;"> 30.0 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Carlton Jt, 1993, Science </td>
   <td style="text-align:left;"> 1149 </td>
   <td style="text-align:left;"> 39.6 </td>
   <td style="text-align:left;"> 28.1 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2020</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Yang T, 2020, Ieee Trans Neural Netw Learn Syst </td>
   <td style="text-align:left;"> 62 </td>
   <td style="text-align:left;"> 31.0 </td>
   <td style="text-align:left;"> 88.2 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Zhu G, 2020, Ieee J Ocean Eng </td>
   <td style="text-align:left;"> 17 </td>
   <td style="text-align:left;"> 8.5 </td>
   <td style="text-align:left;"> 24.2 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> De A, 2020, Ieee Trans Intell Transp Syst </td>
   <td style="text-align:left;"> 16 </td>
   <td style="text-align:left;"> 8.0 </td>
   <td style="text-align:left;"> 22.8 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Huntington Hp, 2020, Nat Clim Chang </td>
   <td style="text-align:left;"> 12 </td>
   <td style="text-align:left;"> 6.0 </td>
   <td style="text-align:left;"> 17.1 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Khooban Mh, 2020, Ieee Trans Power Electron </td>
   <td style="text-align:left;"> 9 </td>
   <td style="text-align:left;"> 4.5 </td>
   <td style="text-align:left;"> 12.8 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2019</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Lenssen Njl, 2019, J Geophys Res -Atmos </td>
   <td style="text-align:left;"> 60 </td>
   <td style="text-align:left;"> 20.00 </td>
   <td style="text-align:left;"> 24.0 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Zhang M, 2019, Saf Sci </td>
   <td style="text-align:left;"> 38 </td>
   <td style="text-align:left;"> 12.67 </td>
   <td style="text-align:left;"> 15.2 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Lombard F, 2019, Front Mar Sci </td>
   <td style="text-align:left;"> 35 </td>
   <td style="text-align:left;"> 11.67 </td>
   <td style="text-align:left;"> 14.0 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Lin Z, 2019, Ieee Geosci Remote Sens Lett </td>
   <td style="text-align:left;"> 31 </td>
   <td style="text-align:left;"> 10.33 </td>
   <td style="text-align:left;"> 12.4 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Dai Sl, 2019, Ieee Trans Neural Netw Learn Syst </td>
   <td style="text-align:left;"> 30 </td>
   <td style="text-align:left;"> 10.00 </td>
   <td style="text-align:left;"> 12.0 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2018</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Wang N, 2018, Ieee Trans Fuzzy Syst </td>
   <td style="text-align:left;"> 88 </td>
   <td style="text-align:left;"> 22.0 </td>
   <td style="text-align:left;"> 17.0 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Galil Bs, 2018, Estuar Coast Shelf Sci </td>
   <td style="text-align:left;"> 68 </td>
   <td style="text-align:left;"> 17.0 </td>
   <td style="text-align:left;"> 13.2 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Trenberth Ke, 2018, Earth Future </td>
   <td style="text-align:left;"> 65 </td>
   <td style="text-align:left;"> 16.2 </td>
   <td style="text-align:left;"> 12.6 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Sofiev M, 2018, Nat Commun </td>
   <td style="text-align:left;"> 64 </td>
   <td style="text-align:left;"> 16.0 </td>
   <td style="text-align:left;"> 12.4 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Oda T, 2018, Earth Syst Sci Data </td>
   <td style="text-align:left;"> 64 </td>
   <td style="text-align:left;"> 16.0 </td>
   <td style="text-align:left;"> 12.4 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2017</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Waller Cl, 2017, Sci Total Environ </td>
   <td style="text-align:left;"> 146 </td>
   <td style="text-align:left;"> 29.2 </td>
   <td style="text-align:left;"> 21.12 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Selim Ms, 2017, Prog Mater Sci </td>
   <td style="text-align:left;"> 113 </td>
   <td style="text-align:left;"> 22.6 </td>
   <td style="text-align:left;"> 16.35 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Freeman E, 2017, Int J Climatol </td>
   <td style="text-align:left;"> 111 </td>
   <td style="text-align:left;"> 22.2 </td>
   <td style="text-align:left;"> 16.06 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Bouman Ea, 2017, Transport Res Part D-Transport Environ </td>
   <td style="text-align:left;"> 110 </td>
   <td style="text-align:left;"> 22.0 </td>
   <td style="text-align:left;"> 15.92 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Geertsma Rd, 2017, Appl Energy-A </td>
   <td style="text-align:left;"> 109 </td>
   <td style="text-align:left;"> 21.8 </td>
   <td style="text-align:left;"> 15.77 </td>
  </tr>
  <tr grouplength="5"><td colspan="4" style="border-bottom: 0;"><strong>2016</strong></td></tr>
<tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Poli P, 2016, J Clim </td>
   <td style="text-align:left;"> 404 </td>
   <td style="text-align:left;"> 67.3 </td>
   <td style="text-align:left;"> 42.56 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Romans Bw, 2016, Earth-Sci Rev </td>
   <td style="text-align:left;"> 184 </td>
   <td style="text-align:left;"> 30.7 </td>
   <td style="text-align:left;"> 19.38 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Wang N, 2016, Ieee Trans Control Syst Technol-A </td>
   <td style="text-align:left;"> 150 </td>
   <td style="text-align:left;"> 25.0 </td>
   <td style="text-align:left;"> 15.80 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Dai Sl, 2016, Ieee Trans Ind Electron </td>
   <td style="text-align:left;"> 135 </td>
   <td style="text-align:left;"> 22.5 </td>
   <td style="text-align:left;"> 14.22 </td>
  </tr>
  <tr>
   <td style="text-align:left;padding-left: 2em;" indentlevel="1"> Bakir A, 2016, Environ Pollut </td>
   <td style="text-align:left;"> 133 </td>
   <td style="text-align:left;"> 22.2 </td>
   <td style="text-align:left;"> 14.01 </td>
  </tr>
</tbody>
</table></div>

]
.panel[.panel-name[Overall time period]

]

]

.panel[.panel-name[2018:2017]
<img src="./figuresNew/2manuscript_cited.png" width="50%" style="display: block; margin: auto;" />

]

.panel[.panel-name[2016]
<img src="./figuresNew/3manuscript_cited.png" width="50%" style="display: block; margin: auto;" />

]

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### Co-Citation of Articles Network

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### Top Authors

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### Scientific Productivity

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### Most Cited Authors

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### Authors Dominance Ranking

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<img src="./figuresNew/author_dominance.png" width="50%" style="display: block; margin: auto;" />
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### Journals