# Information Security Applications in Smart Cities: A Bibliometric Analysis of Emerging Research
## 3 Materials and Method  
The bibliometric analysis uses statistical methods to evaluate the evolution of a particular research area. In this sense, it is possible to (i) evaluate the number of publications, the level of quality, the impact, and the contribution of the results; (ii) to carry out a mapping of the scientific activities of the authors; (iii) to understand networks of citations based on the authors; (iv) to obtain a real and detailed visualization of the results and intellectual structures of a scientific domain; (v) to promote the construction of knowledge; (vi) to monitor the evolution of a research field and (vii) to clarify unexplored research topics. In the past ten years, the advance of cybersecurity research has developed significantly by influential authors in different journals and research areas. The present study consists of a technical and structured analysis of the progress of literature on cybersecurity, with the objectives of presenting collaborations in the editorial production of researchers, highlighting new insights on the role of information security engineering in the world, and stimulating development on future research lines. To direct the research, some questions are posed:  
* _Q1--What are the patterns of information security applications found in research on smart cities?_
* _Q2--What are the most demanding areas for information security in smart cities studies?_
* _Q3--What research has the most influence on the application of information security in smart cities?_  
To answer these questions, this study adopts a theoretical approach, aiming to understand the state-of-the-art information security and smart cities research fields through bibliometrics and content analysis. Figure 1 shows the research design used in this paper, which consists of five steps. Step 1 starts with the data sources definition, considering the Scopus database, followed by search string creation. In this study, two combinations of keywords were defined to compose the search string: (I) \"information security\" and \"smart city\"; and (II) \"cyberattacks\" and \"smart city\". These terms are broad and exp  
Figure 1: Research design. the different knowledge application areas of the theme. The search was applied to titles, abstracts, and keywords of complete published articles. In Step 2, the dataset consists of complete articles published in journals indexed in Scopus, ranging from 2015 to 2023. We decided to start searching for published results from 2015 due to the high number of citations from one of the articles of greater relevance to the area, published in the same year. The work entitled \"Cyber security challenges in smart cities: Safety, security and privacy\", indicated in the reference list, has obtained 650 citations to date [15]. For this reason, we consider this time interval as the most relevant to collect data. A filter was used to remove articles that emerged from books, categorized. The purpose of using this filter was to focus on the article and conference reviews with significant academic impact and relevance in the research platform. In addition, other categories of publications have also been removed, so the objective is to identify the sectors and fields in which there are one or more surveys and the sectors and methods in which there are no surveys available. The Scopus database was selected due to the broad approach of indexed sources among journals, conferences, and books, increasing the range of data collection for the bibliometrics analyses. As shown in Figure 2, there is a significant increase in articles on information security and smart cities. The search results returned a total of 1978 articles, including conference papers (55.5%) and journal articles (44.5%). In Step 3, the VOSViewer software [144], which is a text-mining tool that supports comprehensive and useful compilation of metadata, supporting data generation, and graph visualization, was used as a bibliometric analysis tool.