• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3544-3564
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• 2022

With the development of the NB-IoT (Narrow band Internet of Things) and smart cities, coupled with the emergence of smart smoke sensors, new requirements and issues have been introduced to study on the deployment of sensors in large spaces. Previous research mainly focuses on the optimization of wireless sensors in some monitoring environments, including three-dimensional terrain or underwater space. There are relatively few studies on the optimization deployment problem of smart smoke sensors, and leaving large spaces with obstacles such as libraries out of consideration. This paper mainly studies the deployment issue of smart smoke sensors in large spaces by considering the fire probability of fire areas and the obstacles in a monitoring area. To cope with the problems of coverage blind areas and coverage redundancy when sensors are deployed randomly in large spaces, we proposed an optimized deployment strategy of smart smoke sensors based on the PSO (Particle Swarm Optimization) algorithm. The deployment problem is transformed into a multi-objective optimization problem with many constraints of fire probability and barriers, while minimizing the deployment cost and maximizing the coverage accuracy. In this regard, we describe the structure model in large space and a coverage model firstly, then a mathematical model containing two objective functions is established. Finally, a deployment strategy based on PSO algorithm is designed, and the performance of the deployment strategy is verified by a number of simulation experiments. The obtained experimental and numerical results demonstrates that our proposed strategy can obtain better performance than uniform deployment strategies in terms of all the objectives concerned, further demonstrates the effectiveness of our strategy. Additionally, the strategy we proposed also provides theoretical guidance and a practical basis for fire emergency management and other departments to better deploy smart smoke sensors in a large space.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.3
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• pp.545-563
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• 2022

Metaverse is a digitally generated world beyond the physical realm; many fashion brands are launching virtual stores in Metaverse. This study explores the cases of flagship stores of fashion brands in Metaverse to understand the peculiarity of Metaverse retailing. This study selected four flagship stores of fashion brands launched on ZEPETO, the largest Metaverse platform in Korea. The characteristics of Metaverse retailing used for case analysis were store (store credibility, servicescape, ease of use), product (content, demos, incentives), social factor (store personnel, store customers), and entertainment (events, games, free gifts). The results illustrate that a transaction system linked to reality could not be established due to technical limitations; it was difficult to obtain specific product information, such as the color, size, and fabric. However, all four fashion brands overwhelmed the traditional retail channels in terms of providing various spatial experiences by operating their virtual stores in global cities related to the heritage and identity of each brand. Furthermore, fashion brands can convey a sense of deviation and fantasy to consumers by delivering unique entertainment activities in Metaverse that they cannot easily provide in real life.

• Journal of the Korea Society of Computer and Information
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• v.27 no.8
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• pp.177-183
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• 2022

The purpose of this study is to examine the current status of the elderly welfare ordinances currently enacted and operated by local governments, analyze the actual conditions and problems of the contents, and suggest the direction of enactment and revision of the elderly welfare ordinances for actively responding to the demand for various welfare services for the elderly. To this end, the scope of the study was specified by ordinances in Gwangju Metropolitan City, five autonomous districts, Jeollanam-do, and 22 cities and counties, and the criteria for content analysis of the elderly welfare ordinance of these local governments were selected and compared and analyzed in the four major areas of elderly welfare: income and jobs, care, health, leisure activities, and social participation. According to the analysis results, the direction of enacting the ordinance is to secure financial resources for the elderly welfare budget, develop differentiated welfare policies for the elderly that reflect the characteristics of each local government, expand ordinances related to infectious diseases, enact ordinances for medical support for non-infectious diseases, and enact customized ordinances for the elderly living alone. Finally, the limitations on the research subject and analysis scope of this study and future research directions were presented.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.63-73
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• 2021

In order to effectively promote a smart city, various urban information must be opened and linked, and the information system that each member can share is required. In addition, it is necessary to establish a cooperative system in which citizens and citizen's organizations can participate. In this study, the components and conceptual model of a smart city platform were proposed to create a smart city that enables citizen participation. Its components include sensors for collecting data from the real world, information storage and management, information sharing and standard system, citizens' personal information protection and management system, utilization and service, etc. For the conceptual model, roles of smart city members were defined, so that citizen-centered participation and services could be made. It also includes data collection, information linkage and sharing, and service configuration system. Citizens can perform various roles such as data collector and provider, service planner or requestor, service beneficiary, etc. Ultimately, free communication and exchange of opinions with citizens is a key factor in the success of smart cities.

• The Journal of Korean Academic Society of Nursing Education
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• v.27 no.4
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• pp.381-391
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• 2021

Purpose: This study aimed to identify the influence of learning presence and self-directed learning ability on nursing students' learning satisfaction according to the online learning method. Methods: The participants of this study were 167 nursing students attending three universities in different cities. The data were collected from July 16 to July 23, 2021, via an online self-reported questionnaire. Using SPSS WIN 27.0, data were analyzed by descriptive statistics, Pearson's correlation coefficient and a multiple regression analysis. Results: The most effective online learning method experienced by nursing students was asynchronous online learning according to 58.2% of the respondents, while 30.3% of the respondents answered synchronous online learning. The main merit of asynchronous online learning was that it was possible to listen repeatedly (61.7%) to lectures, and the top advantage of synchronous online learning was that the location of the class was free (53.3%). In asynchronous online learning, the factors that significantly affected nursing students' learning satisfaction were cognitive presence (𝛽=.60, p<.001) and emotional presence (𝛽=.25, p<.001). These variables accounted for 56% of their learning satisfaction (F=54.12, p<.001). Similarly, cognitive presence (𝛽=.64, p<.001) and emotional presence (𝛽=.21, p=.001) in synchronous online learning, were the factors cited for significantly affecting learning satisfaction. The explanatory power was 62% (F=69.19, p<.001). Conclusions: In conclusion, it was found that cognitive and social presence from the learning presence factors in both asynchronous and synchronous online learning influence and enhance nursing students' learning satisfaction. Therefore, these results provide important data for future online class design in nursing education.

• Parasites, Hosts and Diseases
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• v.60 no.4
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• pp.261-271
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• 2022

This study provides an overview of the current status of clonorchiasis and cholangiocarcinoma (CCA), and their relationship in Korea during 2012-2020. Data were obtained from the Health Insurance Review & Assessment Service of Korea. Cluster, trend, and correlation analyses were performed. Gyeongsangnam-do and Seoul had the highest average number of cases (1,026 and 4,208) and adjusted rate (306 and 424) for clonorchiasis and CCA, respectively. The most likely clusters (MLC) for clonorchiasis and CCA were Busan/Gyeongsangnam-do/Ulsan/Daegu/Gyeongsangbuk-do (Relative Risk; RR=4.55, Likelihood Ratio; LLR=9,131.115) joint cluster and Seoul (RR=2.29, LLR=7,602.472), respectively. The MLC for clonorchiasis was in the southeastern part of Korea, while that for CCA was in the southern part. Clonorchiasis showed a decreasing trend in the southeastern districts, while increased in the southwestern districts. Cities in the central region had a decreasing trend, while the western districts had an increasing trend. In most adults (30-59), infection rate of clonorchiasis showed a significant decrease until 2018, while thereafter increased, although not significant. CCA showed a sharply decreasing tendency. The incidence of clonorchiasis and CCA were positively correlated. In general, the correlation was weak (r=0.39, P<0.001), but it was strongly positive around the 4 river basins (r=0.74, P<0.001). This study might provide an analytic basis for developing an effective system against clonorchiasis and CCA.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.2
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• pp.294-305
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• 2022

Recently, drones have been widely used to solve environmental problems such as environmental protection and natural disaster monitoring. This study focuses on the problem of the search altitude of drones when using drones to search for air pollution in order to maintain the urban air environment. In particular, when exploring air pollution in cities using drones, various experiments are conducted to determine the appropriate search altitude for each air pollution source and each communication module. Through the experiment, the maximum measurable altitude for the most common air pollutants, such as CO (carbon monoxide), NO₂ (nitrogen dioxide), O₃ (ozone), and P10, P2.5 (fine dust), was identified, and the effective search altitude for each air pollution source was determined. As a result of the experiment, three types of drone search altitudes including legally measurable altitudes were suggested. The communication module measurable altitude was 60m to 120m depending on the communication module, and the effective measurable altitude was analyzed from 10m to 100m.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.347-353
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• 2022

The Purpose of this study is to investigate mediating effects of satisfaction in major on the causal relationship between job image of students majoring airline service and career preparation behavior. This study employs a survey questionnaire to examine the mediating effect of satisfaction in major. A 33-item survey questionnaire was administered to 210 students in the universities in 4 Metropolitan cities. The research data are analyzed using six statistical methods: factor analysis, reliability analysis, t-test, ANOVA, correlation analysis, and three-step mediated regression analysis. As a result of the analysis, there is mediating effect of satisfaction in major in the causal relationship between job image and career preparation behavior.

• Journal of Korean Academy of Nursing
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• v.52 no.4
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• pp.464-475
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• 2022

Purpose: This study aimed to identify the mediating effects of depression amid the influence of fear and social distancing arising from Coronavirus disease 2019 (COVID-19) in Korean women's suicidal ideation. Methods: A descriptive correlation study was conducted. Study participants, recruited by Hankook Research from March 2 to March 5, 2021, included 300 women aged 19 to 49 living in South Korea, and 100 people were randomly allocated and enlisted for each age group out of 700,000 Hankook Research Panels recruited in advance from 17 cities and provinces nationwide. Data were collected through a self-reported questionnaire and analyzed using Pearson's correlation coefficient and Hayes' Process Macro Model 4 with 95% bias-corrected bootstrap confidence interval via SPSS statistics 27.0. Results: Suicidal ideation was significantly correlated with fear of COVID-19 (r = .16, p = .006) and depression (r = .65, p < .001). The mediation effect of depression in the relationship between the fear of COVID-19 and suicidal ideation was found to be significant (B = 0.40, boot 95% CI: 0.21~0.61). However, social distancing did not significantly affect suicidal ideation via depression (B = - 0.79, boot 95% CI: - 1.94~0.26). Conclusion: It is necessary to develop and apply interventions to prevent depression and suicidal behaviors by continuously observing and reducing the negative psychological responses caused by COVID-19.

• Journal of radiological science and technology
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• v.45 no.3
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• pp.263-272
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• 2022

This study investigated small and medium-sized hospital workers' knowledge of COVID-19, the infection-control-related fatigue and stress levels, and the factors that impacted their performance during the COVID-19 pandemic. Using a cross-sectional design, data were collected from 137 hospital workers from four small and medium-sized hospitals in S and C cities. Data were analyzed using descriptive statistics, a t-test, analysis of variance(ANOVA), Pearson's correlation coefficient, and multiple linear regression analysis. Small and medium-sized hospital workers' knowledge of COVID-19 revealed a correct answer rate of 66%. An average of 3.00 points out of 4 for infection control performance and 3.32 and 3.17 points out of 5 for infection-control-related fatigue and stress, respectively, were found. The level of knowledge regarding COVID-19 significantly differed by age and marriage (p<0.05), while infection control performance significantly differed by age, marriage, and infection control education experience (p<0.05). Infection-control-related fatigue and stress differed depending on the COVID-19 control education experience, economic and social prejudice, and fear of discrimination. There were positive correlations between knowledge and infection control performance, and infection control performance and infection-control-related fatigue and stress (p<0.001). This study showed that the factors that affected small and medium-sized hospital workers' performance included knowledge of "environmental management," "difficulties due to new role requirements," "presence or absence of infection education experience," "job type," and "age." These results suggest that practical and detailed education programs should be systematically developed and implemented for effective infection control.