# A Network Analysis Approach to Detecting Social Issues with Web-Based Data
## 4 Illustrative Example: Diesel Exhaust Fluid Issue in South Korea
### Analyses  
The community #86 consisted of 46 keywords, including the high-degree centrality keyword '(DEF), and the keywords '(Hughway bus), '(Diesel vehicle), '(Lorry), '(Skyrocketing), '(Skyrocketing), '(Market disruption). In fact, the transportation of many people and national industries was largely dependent on vehicles that require DEF injection, so shutting down vehicles such as highway buses andlories, due to the shortage and skyrocketing prices of DEF, was the biggest problem with the issue. Among the keywords that make up community #86, the keywords that showed an increase in degree centrality compared to the previous time period were '(DEF), '(Injection), '(Wanju), '(Wanju), '(Wanju), '(Aton Industry), '(Kisan), etc. South Korea was experiencing a nationwide DEF shortage, causing the price of DEF to skyrocket, and threatening to shut down many of the vehicles around us, including fire trucks, delivery trucks, and agricultural equipment. At that time, the Aton Industry, a DEF manufacturing company based in Iksan-si, South Korea, signed a convention with local governments, including Wanju-gun, to prioritize the supply of DEF to the region. Even with a limited amount per day, Aton Industry sold DEF to local residents on a daily basis at a reasonable price until the DEF issue was stabilized. In addition, the companies involved in the convention were provided with sufficient quantities to ensure that their industrial activities were not constrained. Aton Industry was praised for its efforts to stabilize the local industry, even though it could have sold at a higher price and made a large profit during the DEF shortage. As a result, Aton Industry and the local governments, such as Iksan-si and Wanju-gun, attracted attention at the time. The social issue candidates with the next highest impact score were community #276 and community #42. The main keywords in the community #276 were '(Resistant bacteria), '(Non-human), '(Bacteria), '(Carbapenen) and '(Carbapen). The issue was related to the 'Second National Antimicrobial Resistance Management Plan', which was established by the South Korean Ministry of Health and Welfare  
Figure 7: Most urgent social issue community #86.  
at the time to manage antibiotic resistance. Antimicrobial resistance refers to the ability of bacteria to resist and survive certain antibiotics. Antibiotic-resistant bacteria are generated and spread through multiple routes such as people, agriculture, livestock, fisheries, food, and the environment, so a governmental response is necessary. The development of antibiotic-resistant bacteria is closely associated with the use of antibiotics, and South Korea has been found to have the third highest human antibiotic use among OECD countries. Therefore, South Korea has established a new policy to ensure that the right amount and type of antibiotics are used to reduce the development of antibiotic-resistant bacteria. The main keywords of community #42 were '(Medical certificate), '(Medical certificate), '(Painkiller), '(Prescription), '(Therapeutic purpose), and '(Fentanyl). In fact, at the time, doctors who overprescribed fentanyl, a narcotic painkiller, and young men in their 20s who prescribed and took fentanyl were arrested by the police and made headlines. Since then, drug-related crime has been on the rise in South Korea, and even today, the drug-related crime among young people remains a major social problem of South Korea. This study detected the social issues that people paid attention to. If the most frequently appearing topics were identified based on the frequency as in previous studies, the topics would be serious social problems that most people already know about. In fact, the most mentioned keywords in the news articles used in this study were primarily related to the COVID-19 pandemic, including COVID-19, vaccine, and inoculation. Therefore, this study adequately detected social issue topics that attract people's attention among the various topics that exist in our society.