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1.
Economic and Environmental Geology ; 56(2):155-166, 2023.
Article in English | Web of Science | ID: covidwho-20231322

ABSTRACT

Through COVID-19, the importance of supply chain management of raw material minerals has been maximized. In particular, supply chain management is important for rare metals, which are difficult to manage demand and supply, in order to secure raw materials for the parts and materials industry that Korea is actively promoting. In this study, a system was established and evaluated to select Critical minerals that need to respond to Korea's industrial structure and global risks by quantifying tangible and intangible risk factors. Global Supply Concentration, Supplying country risk, Policy Social Environment Regulation, Domestic Import Instability, Risk responsiveness, Market Scale, Demand Fluctuation and Economic Importance were evaluated as evaluation indicators. The degree of risk and risk impact were quantitatively measured using the criticality matrix-criticality level. After evaluating 40 types of minerals used in domestic new growth businesses, 15 types of Critical minerals(Li, Pt, Co, V, REE, Mg, Mo, Cr, Ti, W, C, Ni, Al, Mn, Si) in Korea were selected. The results are expected to be used to establish policies to strengthen resource security and to make decisions to form a company's raw material portfolio.

2.
Computers, Materials and Continua ; 75(2):4231-4253, 2023.
Article in English | Scopus | ID: covidwho-2315719

ABSTRACT

Recently, with the normalization of non-face-to-face online environments in response to the COVID-19 pandemic, the possibility of cyberattacks through endpoints has increased. Numerous endpoint devices are managed meticulously to prevent cyberattacks and ensure timely responses to potential security threats. In particular, because telecommuting, telemedicine, and tele-education are implemented in uncontrolled environments, attackers typically target vulnerable endpoints to acquire administrator rights or steal authentication information, and reports of endpoint attacks have been increasing considerably. Advanced persistent threats (APTs) using various novel variant malicious codes are a form of a sophisticated attack. However, conventional commercial antivirus and anti-malware systems that use signature-based attack detection methods cannot satisfactorily respond to such attacks. In this paper, we propose a method that expands the detection coverage in APT attack environments. In this model, an open-source threat detector and log collector are used synergistically to improve threat detection performance. Extending the scope of attack log collection through interworking between highly accessible open-source tools can efficiently increase the detection coverage of tactics and techniques used to deal with APT attacks, as defined by MITRE Adversarial Tactics, Techniques, and Common Knowledge (ATT&CK). We implemented an attack environment using an APT attack scenario emulator called Carbanak and analyzed the detection coverage of Google Rapid Response (GRR), an open-source threat detection tool, and Graylog, an open-source log collector. The proposed method expanded the detection coverage against MITRE ATT&CK by approximately 11% compared with that conventional methods. © 2023 Tech Science Press. All rights reserved.

3.
Lrec 2022: Thirteen International Conference on Language Resources and Evaluation ; : 3048-3055, 2022.
Article in English | Web of Science | ID: covidwho-2307348

ABSTRACT

This paper introduces a multi-lingual database containing translated texts of COVID-19 mythbusters. The database has translations into 115 languages as well as the original English texts, of which the original texts are published by World Health Organization (WHO). This paper then presents preliminary analyses on latin-alphabet-based texts to see the potential of the database as a resource for multilingual linguistic analyses. The analyses on latin-alphabet-based texts gave interesting insights into the resource. While the amount of translated texts in each language was small, character bi-grams with normalization (lowercasing and removal of diacritics) turned out to be an effective proxy for measuring the similarity of the languages, and the affinity ranking of language pairs could be obtained. Additionally, the hierarchical clustering analysis is performed using the character bigram overlap ratio of every possible pair of languages. The result shows the cluster of Germanic languages, Romance languages, and Southern Bantu languages. In sum, the multilingual database not only offers fixed set of materials in numerous languages, but also serves as a preliminary tool to identify the language family using text-based similarity measure of bigram overlap ratio.

4.
5th International Conference on Artificial Intelligence in Information and Communication, ICAIIC 2023 ; : 733-735, 2023.
Article in English | Scopus | ID: covidwho-2298982

ABSTRACT

The use of delivery platforms has become widespread due to the impact of the Covid-19 and the O2O industry. However, the ELEME delivery platform, a subsidiary of Alibaba Group, which represents China, has recently been losing market share. This means that companies need to constantly look at strategies to attract new customers and maintain existing ones. In general, it costs at least five times more to attract new customers than it does to manage existing customers. This paper attempts to predict customer churn using the ELEME customer dataset to develop strategies to identify and prevent churn in advance. The results of the analysis using machine learning approach found that the most influential feature that can predict churn is the number of clicks made by the user. This paper presents the process and explanation of applying various algorithms for predicting customer churn on a distribution platform. It also proposes strategies for dealing with customer churn. © 2023 IEEE.

5.
Biosensors and Bioelectronics: X ; 13 (no pagination), 2023.
Article in English | EMBASE | ID: covidwho-2297324

ABSTRACT

Herein, we establish a novel isothermal digital amplification system termed digital nicking and extension chain reaction system-based amplification (dNESBA) by utilizing the isothermal NESBA technique and the newly developed miniaturized fluorescence monitoring system (mFMS). dNESBA enables parallel isothermal NESBA reactions in more than 10,000 localized droplet microreactors and read the fluorescence signals rapidly in 150 s by mFMS. This system could identify the genomic RNA (gRNA) extracted from target respiratory syncytial virus A (RSV A) as low as 10 copies with remarkable specificity. The practical applicability of dNESBA was also successfully verified by reliably detecting the gRNA in the artificial sputum samples with excellent reproducibility and accuracy. Due to the intrinsic advantages of isothermal amplifying technique including the elimination of the requirement of thermocycling device and the enhanced portability of the miniaturized read-out equipment, the dNESBA technique equipped with mFMS could serve as a promising platform system to achieve point-of-care (POC) digital molecular diagnostics, enabling absolute and ultra-sensitive quantification of various infectious pathogens even in an early stage.Copyright © 2023

6.
Computers, Materials and Continua ; 74(2):4363-4379, 2023.
Article in English | Scopus | ID: covidwho-2242182

ABSTRACT

Over the last several years, remote collaboration has been getting more attention in the research community because of the COVID-19 pandemic. In previous studies, researchers have investigated the effect of adding visual communication cues or shared views in collaboration, but there has not been any previous study exploring the influence between them. In this paper, we investigate the influence of view types on the use of visual communication cues. We compared the use of the three visual cues (hand gesture, a pointer with hand gesture, and sketches with hand gesture) across two view types (dependent and independent views), respectively. We conducted a user study, and the results showed that hand gesture and sketches with the hand gesture cues were well matched with the dependent view condition, and using a pointer with the hand gesture cue was suited to the independent view condition. With the dependent view, the hand gesture and sketch cues required less mental effort for collaborative communication, had better usability, provided better message understanding, and increased feeling of co-presence compared to the independent view. Since the dependent view supported the same viewpoint between the remote expert and a local worker, the local worker could easily understand the remote expert's hand gestures. In contrast, in the independent view case, when they had different viewpoints, it was not easy for the local worker to understand the remote expert's hand gestures. The sketch cue had a benefit of showing the final position and orientation of the manipulating objects with the dependent view, but this benefit was less obvious in the independent view case (which provided a further view compared to the dependent view) because precise drawing in the sketches was difficult from a distance. On the contrary, a pointer with the hand gesture cue required less mental effort to collaborate, had better usability, provided better message understanding, and an increased feeling of co-presence in the independent view condition than in the dependent view condition. The pointer cue could be used instead of a hand gesture in the independent view condition because the pointer could still show precise pointing information regardless of the view type. © 2023 Tech Science Press. All rights reserved.

7.
Transportation Research Record ; 2022.
Article in English | Web of Science | ID: covidwho-2194926

ABSTRACT

Recent studies have applied the percolation theory to analyze the connectivity of networks in the transportation field. However, research was conducted in a manner that completely removed the function of nodes or links. There was a limit in that applying public transportation was difficult to guarantee the right to move the captive rider. In this study, penalties were imposed on public transportation nodes in the form of wait times to remove the function of node partially. Accordingly, the travel time of a network was calculated by optimal strategy assignment to reflect passenger behavior. When nodes were randomly penalized without transfer distinctions, there was a critical point of travel-time increase between cases with penalties of 50 and 60 nodes, respectively, and percolation was observed indirectly. A large and global effect of increased travel time was observed when the penalties were issued only to transfer stations. The application of a trip frequency weight increases the effect of penalties on medium- or short-timed trips. The results of this study can be used to establish quarantine policies for controlling public transportation networks. Furthermore, it is the first attempt at observing percolation by partially limiting its function in the form of node penalties in a public transportation network.

8.
Open Forum Infectious Diseases ; 9(Supplement 2):S520-S521, 2022.
Article in English | EMBASE | ID: covidwho-2189822

ABSTRACT

Background. The superinfection of multidrug-resistant bacteria is an important complication in critically ill COVID-19 patients. An outbreak of carbapenemresistant Acinetobacter baumannii (CRAB) occurred in an isolation ward for COVID-19. We performed an outbreak investigation, and successfully controlled the outbreak with the enhanced environmental cleaning and additional gowning and gloving. Methods. This study analyzed all COVID-19 patients with CRAB in any specimen, who admitted to an isolation ward for COVID-19 of a tertiary hospital in South Korea from October to November 2021. Results. During the outbreak period, a total of 23 patients with COVID-19 and CRAB were identified (Figure 1). Index case was 85-year old female patient who was referred from a long-term care facility. The mean age of cases was 72.9 and 14 (60.9%) patients were male. In most patients (91.3%), CRAB were identified in sputum culture, two were identified in blood culture at initial, and four patients were identified in sputum and blood culture at the same time. Most of the patients were applying high flow nasal cannula (26.1%) or mechanical ventilation (60.9%)(Table1). As shown in figure2, CRAB outbreak occurred mainly in the wards around the index case, and in particular, environmental culture was carried out in the area marked with a rectangle. CRAB was cultured on the floor, air inlet, air outlet, and window frame of the ward except for wards 3305 and 3319. Phenotypic antimicrobial resistance patterns of CRAB isolates from patients and environment were identical, and additional whole genome sequencing analyses are ongoing to find the clonality of isolates. We applied the infection control measures with the enhanced environmental cleaning using sodium hypochlorite(NaClO) 1000ppm and phenolic compounds more than twice a day, enhanced hand hygiene, and additional gowning and gloving over personal protective equipment (PPE) mandatory for COVID-19 on 29th October. No additional CRAB cases occurred since 2nd November 2021 for two weeks. Conclusion. Even when PPEs and precautions for COVID-19 are applied to isolation wards for COVID-19, it is helpful for preventing transmission of multidrug-resistant bacteria to apply additional contact precautions and environmental cleaning.

9.
Open Forum Infectious Diseases ; 9(Supplement 2):S210-S211, 2022.
Article in English | EMBASE | ID: covidwho-2189635

ABSTRACT

Background. Invasive aspergillosis (IA) is a great threat to the severely immunocompromised and patients with coronavirus disease (COVID-19). However, diagnosis of IA is often difficult due to need for invasive biopsy and low sensitivity of other diagnostic tests. Next-generation sequencing (NGS) of plasma cell free DNA (cfDNA) can be a novel non-invasive diagnostic modality. We evaluated the clinical accuracy and utility of microbial cfDNA NGS for the diagnosis of IA in patients with hematologic malignancy (HM) and COVID-19. Methods. A single-center prospective study of plasma microbial cfDNA NGS was conducted in a tertiary-care hospital in South Korea. We enrolled adult patients with HM and COVID-19, who suspected IA and performed conventional diagnostic tests for IA. The results of NGS were compared with the diagnosis of IA through conventional methods. IA cases were diagnosed according to EORTC/MSG definitions in patients with HM, and modified AspICU criteria in patients with COVID-19. (Figure 1). Figure 1. Flow chart for the participant selection method used in this study Results. Between March 2021 and January 2022, a total of 33 participants (22 [64.7%] male, median age 66.0 [50.5, 72.0]) were enrolled;19 participants with HM and 15 with COVID-19 were analyzed (Figure1 and Table1). In participants with HM, aspergillus cfDNA was detected in 100% of both proven (1/1) and probable (12/12) IA cases, and 33.3% of both possible (1/3) and no IA (1/3) cases. In participants with COVID-19, 46.2% of probable IA (6/13) showed positive aspergillus cfDNA. Detection rate of aspergillus cfDNA was significantly higher in proven/probable IA cases in participants with HM compared to participants with COVID-19. (100% vs 46.2%, p=0.005) (Figure 2). As shown in Table 2, among proven/probable IA cases, participants with positive aspergillus cfDNA showed significantly higher rate of having uncontrolled hematologic disease, receiving stem cell transplantation and recent chemotherapy. In three participants with HM, non-aspergillus strains confirmed by cfDNA NGS were in accordance with pathogens identified through conventional culture methods. Conclusion. Detection of aspergillus cfDNA showed high concordance in the results of conventional diagnostic methods in proven/probable IA of patients with HM and could be a helpful non-invasive approach to IA diagnosis in those populations.

10.
Open Forum Infectious Diseases ; 9(Supplement 2):S195-S196, 2022.
Article in English | EMBASE | ID: covidwho-2189610

ABSTRACT

Background. COVID-19 increase the risk of invasive pulmonary aspergillosis. However, the risk factors and fungal origin of COVID-19 associated pulmonary aspergillosis (CAPA) is not fully defined yet. We aim to identify the risk factors for CAPA in severe COVID-19 and evaluate association between fungal contamination within the air of negative pressure rooms and diagnosis of CAPAs. Methods. We performed a retrospective case-control study to identify risk factors for CAPA with 420 severe COVID-19 patients from March 2020 to January 2022 who admitted to a tertiary care hospital in South Korea. CAPA was defined with modified AspICU criteria. Control, matched by admission date and severity of COVID-19 at admission, was selected for each case. Air sampling and fungal culture was done on Jan 2022 with a microbial air sampler (MAS-100NT) at 11 spaces in the COVID-19 designated isolation ward including 9 negative pressure isolation rooms (IRs). A cross-sectional comparison between rooms with and without airborne fungal contamination was performed. Results. A total of 420 COVID-19 patients were hospitalized during the study period, and 51 patients were diagnosed with CAPA (prevalence 12.14%, incidence 6.26 per 1000 patient.day). Multivariate analysis showed that older age (odds ratio [OR] 1.051, 95% confidence intervals [CI] 1.006-1.009, p=0.025), mechanical ventilator use (OR 2.692, 95% CI 1.049-6.911, p=0.04), and lymphopenia (OR 4.353, 95% CI 1.727-10.975, p=0.02) were independent risk factors for CAPA. (Table 1, 2) Aspergillus spp. was identified within the air from 7 out of 11 spaces including 6 IRs and 1 doctors' room. (Figure 1). All 6 IRs with positive aspergillus culture were being occupied by patients at least 8 days. Among 6 patients, 3 had already been diagnosed with CAPA whereas the other 3 were not diagnosed with CAPA through the observation period. Among 4 patients in isolation rooms without airborne aspergillus contamination, one patient had been diagnosed as CAPA before air sampling. (Table 3). Conclusion. Association between CAPA and airborne aspergillus contamination within the negative pressure room could not be demonstrated in this study. Rather than environmental factors, patient factors such as older age, ventilator care, and lymphopenia were found to be associated with CAPA diagnosis.

11.
Open Forum Infectious Diseases ; 9(Supplement 2):S194-S195, 2022.
Article in English | EMBASE | ID: covidwho-2189609

ABSTRACT

Background. During the novel coronavirus SARS-CoV-2 pandemic, a considerable number of pneumothorax and pneumomediastinum associated with COVID-19 have been reported, and the incidence was higher in critically ill patients. Despite using a protective ventilation strategy, barotrauma still occurs in COVID-19 patients with invasive mechanical ventilation. This study aims to identify the risk factors and clinical characteristics of pneumothorax and pneumomediastinum in COVID-19 by a matched case-control study. Methods. This retrospective study enrolled adult patients diagnosed with a COVID-19, admitted to a critical care unit in South Korea from 2020 March 1st to 2022 January 31st. COVID-19 patients with pneumothorax and pneumomediastinum were compared, in a 1 to 2 ratio, to a control group of COVID-19 patients without pneumothorax and pneumomediastinum, matched on age, gender, and worst National Institute of Allergy and Infectious Diseases ordinal scale (NIAID-OS). Conditional logistic regression analysis was performed to assess the risk factors for pneumothorax and pneumomediastinum in COVID-19. Results. A total of 427 patients with COVID-19 were admitted during the study period. Of these patients, 24 patients were diagnosed as pneumothorax or pneumomediastinum. When comparing the characteristics of both groups, body mass index (BMI) was significantly lower in the case group (22.8 kg/m2 and 24.7 kg/m2;P = 0.048). BMI was statistically significant risk factor for barotrauma in univariate conditional logistic regression analysis (Odds ratio (OR), 0.85;Confidence interval (CI), 0.72-0.996;P = 0.044) but not in multivariate analysis. For the patients with invasive mechanical ventilation, the period from symptom onset to intubation was longer in the case-patients (13 and 9.5 days;P = 0.032). Univariate conditional logistic regression analysis showed the statistical significance of the period from symptom onset to intubation (OR, 1.14;CI, 1.006-1.293;P = 0.041). Conclusion. In this case-control study with age, gender, severity matching, lower BMI was associated with the pneumothorax in COVID-19, and delayed application of invasive mechanical ventilation might contribute to this complication.

12.
Innov Aging ; 6(Suppl 1):158, 2022.
Article in English | PubMed Central | ID: covidwho-2188820

ABSTRACT

Long-term care is the industry with the highest occupational injury and illness rate in the United States. During the Coronavirus Disease 2019 (COVID-19) Pandemic, healthcare workers have been affected physically and psychologically by increased workload and stress. Such increased physical and psychological demands may increase the risk of injury among long-term care workers. The aim of this study is to assess the impact of COVID-19 on occupational injury or illness incidence among long-term care workers. Analyzing California Workers' Compensation (WC) data reported in 2019 and 2020, the study will report the number and rate of WC claims among California long-term care workers by month and examine changes over time during 2019-2020. The study will also characterize WC claims during 2019-2020 by demographic (age, gender), occupational (occupation, job tenure), and injury or illness characteristics (cause of injury, nature of injury, affected body part) and identify characteristics with greater changes during COVID-19.

13.
13th International Conference on Language Resources and Evaluation Conference, LREC 2022 ; : 3048-3055, 2022.
Article in English | Scopus | ID: covidwho-2167606

ABSTRACT

This paper introduces a multi-lingual database containing translated texts of COVID-19 mythbusters. The database has translations into 115 languages as well as the original English texts, of which the original texts are published by World Health Organization (WHO). This paper then presents preliminary analyses on latin-alphabet-based texts to see the potential of the database as a resource for multilingual linguistic analyses. The analyses on latin-alphabet-based texts gave interesting insights into the resource. While the amount of translated texts in each language was small, character bi-grams with normalization (lowercasing and removal of diacritics) turned out to be an effective proxy for measuring the similarity of the languages, and the affinity ranking of language pairs could be obtained. Additionally, the hierarchical clustering analysis is performed using the character bigram overlap ratio of every possible pair of languages. The result shows the cluster of Germanic languages, Romance languages, and Southern Bantu languages. In sum, the multilingual database not only offers fixed set of materials in numerous languages, but also serves as a preliminary tool to identify the language family using text-based similarity measure of bigram overlap ratio. © European Language Resources Association (ELRA), licensed under CC-BY-NC-4.0.

14.
2022 Ieee/Cvf Conference on Computer Vision and Pattern Recognition Workshops (Cvprw 2022) ; : 2103-2112, 2022.
Article in English | Web of Science | ID: covidwho-2152447

ABSTRACT

The importance of online education has been brought to the forefront due to COVID. Understanding students' attentional states are crucial for lecturers, but this could be more difficult in online settings than in physical classrooms. Existing methods that gauge online students' attention status typically require specialized sensors such as eye-trackers and thus are not easily deployable to every student in real-world settings. To tackle this problem, we utilize facial video from student webcams for attention state prediction in online lectures. We conduct an experiment in the wild with 37 participants, resulting in a dataset consisting of 15 hours of lecture-taking students' facial recordings with corresponding 1,100 attentional state probings. We present PAFE (Predicting Attention with Facial Expression), a facial-video-based framework for attentional state prediction that focuses on the vision-based representation of traditional physiological mind-wandering features related to partial drowsiness, emotion, and gaze. Our model only requires a single camera and outperforms gaze-only baselines.

15.
Computers, Materials and Continua ; 74(2):4363-4379, 2023.
Article in English | Scopus | ID: covidwho-2146422

ABSTRACT

Over the last several years, remote collaboration has been getting more attention in the research community because of the COVID-19 pandemic. In previous studies, researchers have investigated the effect of adding visual communication cues or shared views in collaboration, but there has not been any previous study exploring the influence between them. In this paper, we investigate the influence of view types on the use of visual communication cues. We compared the use of the three visual cues (hand gesture, a pointer with hand gesture, and sketches with hand gesture) across two view types (dependent and independent views), respectively. We conducted a user study, and the results showed that hand gesture and sketches with the hand gesture cues were well matched with the dependent view condition, and using a pointer with the hand gesture cue was suited to the independent view condition. With the dependent view, the hand gesture and sketch cues required less mental effort for collaborative communication, had better usability, provided better message understanding, and increased feeling of co-presence compared to the independent view. Since the dependent view supported the same viewpoint between the remote expert and a local worker, the local worker could easily understand the remote expert’s hand gestures. In contrast, in the independent view case, when they had different viewpoints, it was not easy for the local worker to understand the remote expert’s hand gestures. The sketch cue had a benefit of showing the final position and orientation of the manipulating objects with the dependent view, but this benefit was less obvious in the independent view case (which provided a further view compared to the dependent view) because precise drawing in the sketches was difficult from a distance. On the contrary, a pointer with the hand gesture cue required less mental effort to collaborate, had better usability, provided better message understanding, and an increased feeling of co-presence in the independent view condition than in the dependent view condition. The pointer cue could be used instead of a hand gesture in the independent view condition because the pointer could still show precise pointing information regardless of the view type. © 2023 Tech Science Press. All rights reserved.

16.
Frontiers in Marine Science ; 9, 2022.
Article in English | Scopus | ID: covidwho-2080160

ABSTRACT

Reduced amounts of aerosols blowing into the Yellow Sea (YS), owing to the temporary lockdown of factories in China during COVID-19, resulted in a 15% decrease in spring chlorophyll-a concentration (CHL) in March 2020 compared to its mean March values from 2003 to 2021. Particularly, the effect of land-based AOD is insignificant compared with that of atmospheric aerosols flowing into the YS, as indicated by the currents and wind directions. Hence, the main objective of this study was to understand the relationship between atmospheric aerosols and CHL by quantitatively considering relevant environmental changes using a Random Forest (RF) algorithm. Various input physical forcing variables to RF were employed, including aerosol optical depth (AOD), sea surface temperature (SST), mixed layer depth (MLD), wind divergence (WD), and total precipitation (TP). From the RF-based analysis, we estimated the relative contribution of each physical forcing variable to the difference in CHL during and after the COVID-19 lockdown period. The sensitivity of the RF model to changes in aerosol levels indicated positive effects of increased amounts of aerosols during spring blooms. Additionally, we calculated the quantitative contribution of aerosols to CHL changes. When SST was warmer and TP was lower than their climatology in March 2020, CHL increased by 0.22 mg m-3 and 0.02 mg m-3, respectively. Conversely, when MLD became shallower and AOD was lower than their climatology, CHL decreased as much as 0.01 mg m-3 and 0.20 mg m-3. Variations in WD caused no significant change in CHL. Overall, the specific estimations for reduced spring blooms were caused by a reduction in aerosols during the COVID-19 lockdown period. Furthermore, the RF developed in this study can be used to examine CHL changes and the relative role of significant environmental changes in biological blooms in the ocean for any normal year. Copyright © 2022 Baek, Park, Kim, Lee, Lee, Lee and Jo.

17.
Journal of Korean Society for Atmospheric Environment ; 38(4):524-541, 2022.
Article in En ko | Scopus | ID: covidwho-2040285

ABSTRACT

This study evaluated the characteristics of PM2.5 pollution and long-range atmospheric transport (LRAT) at the Baengnyeong and Jeju Air Quality Research Centers in South Korea during 2018~2020. The mean concentration of PM2.5 was constant in Baengnyeong but decreased in Jeju owing to COVID-19. The significant seasonal variations of OC, EC, and NO3- in Baengnyeong and Jeju with the highest concentrations in winter may be due to the influence of high PM2.5 episodes. Meanwhile, the concentrations of SO42- and NH4+ were constant throughout the year in Baengnyeong, resulting from regional inflow from surrounding areas. The influence of anthropogenic sources and secondary formation of PM2.5 increased in summer and decreased in autumn at both sites, which was also observed at other background sites. The dominance of NO3-, K+, and Cl- in Baengnyeong was due to the influence of combustion sources and LRAT. The source of SO42-, NH4+, V, and Ni in Jeju was identified as industrial activities with the highest contribution in summer. The secondary formation of PM2.5 with external inflow effects was dominant in Baengnyeong and Jeju. The main emission source area of PM2.5 for both Baengnyeong and Jeju was East China (Hebei, Shandong, Jangsu, and Anhui), but the chemical composition and sources of PM2.5 were different between Baengnyeong and Jeju. The result of this study can be a basis for future monitoring and modeling studies on the influence of LRAT in background areas. © 2022, Journal of Korean Society for Atmospheric Environment. All rights reserved.

18.
IEEE Region 10 Conference (TENCON) ; : 429-434, 2021.
Article in English | English Web of Science | ID: covidwho-1883150

ABSTRACT

COVID-19, particularly vaccines, have caused an 'infodemic' online;a rapid and vast spread of unreliable information. While vaccines can minimize the detrimental effects of COVID-19, misinformation, fearmongering, and 'anti-vax' movements have fostered opposition which is especially prevalent on Twitter. Understanding public emotions related to vaccines is an important, yet inconsistent, area of research. To resolve some of the inconsistencies in the field, we develop and apply two integrated emotion detection models to a longitudinal sample of COVID-19 vaccine related tweets (n = 823,748). Contrary to prior research, which concluded that positive emotions are the most dominant emotion (e.g., trust and happiness), the balanced emotion model (consisting of eight emotions) shows that fear (41%) is the most dominant emotion. The extended emotion model (consisting of sixteen emotions) shows various negative emotions such as panic (27%), fear (22%), and shame (37%) as the dominant emotions in the tweet hashtag groups such as COVID-19, Vaccine, and Anti-vaxxers.

19.
American Journal of Respiratory and Critical Care Medicine ; 205:2, 2022.
Article in English | English Web of Science | ID: covidwho-1880865
20.
Journal of Current Southeast Asian Affairs ; 2022.
Article in English | Scopus | ID: covidwho-1846753

ABSTRACT

We examine the Thai government's politicised COVID-19 containment strategies, which have been challenged by Thai protesters. Although we use securitisation theory as an explanatory framework, we argue that researchers using this theory can explain the issues only if they simultaneously use social-conflict theory to explain the interactions between securitising actors and their audiences. By supplementing securitisation theory with social-conflict theory, we have found that the roles of securitising actors and audiences are not fixed. In our case study of Thailand, the Thai government and protesters have played two roles simultaneously: the role of a securitising actor and the role of an audience. This finding suggests that successful securitisation is impermanent;that is, it is subject to change over time. Securitisation may be successful, but the success can only be temporary because as new actors or resources enter the picture, the previously successful securitisation will, at some point, diminish. © The Author(s) 2022.

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