• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.171-187
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• 2023

Objectives: Aircraft cabin cleaning work is characterized by being performed within a limited time in a narrow and enclosed space. The objective of this study was to evaluate the exposure levels to dust, ultra fine dust(PM2.5) and black carbon(BC) among aircraft cabin cleaners. Methods: Active personal air sampling for respirable dust(n=73) and BC(n=47) was conducted during quick transit cleaning(cabin general and vacuum-specific) and seat cover replacement and total dust and PM2.5 were area-air-sampled as well. Also, size distribution of particle was identified with the cleaning workers targeted. Dusts were collected with PVC filters using gravimetric analysis. The concentration of PM2.5 and the particle size distribution were measured with real-time direct reading portable equipment using light scattering analysis. The concentration of BC was measured by aethalometer(filter-based real-time light absorption analysis instrument). Results: The geometric mean of respirable dust was the highest at vacuum cleaning as 74.4 ㎍/m³, following by replacing seat covers as 49.3 ㎍/m³ and cabin general cleaning as 47.8 ㎍/m³ . The arithmetic mean of PM2.5 was 4.83 ~ 9.89 ㎍/m³ inside the cabin, and 28.5~44.5 ㎍/m³ outside the cabin(from bus and outdoor waiting space). From size distribution, PM_2.5/PM₁₀ ratio was 0.54 at quick transit cleaning and 0.41 at replacing seat covers. The average concentration of BC was 2~7 ㎍/m³, showing a high correlation with the PM2.5 concentration. Conclusions: The hazards concentration levels of aircraft cabin cleaners were very similar to those of roadside outdoor workers. As the main source of pollution is estimated to be diesel vehicles operating at airports, and it is necessary to replace older vehicles, strengthen pollutant emission control regulations, and introduce electric vehicles. In addition, it is necessary to provide as part of airport-inftastructure a stable standby waiting space for aircraft cabin cleaners and introduce a systematic safety and health management system for all workers in the aviation industry.

• 한국정보교육학회:학술대회논문집
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• 2021.08a
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• pp.85-91
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• 2021

School violence has long been recognized as a social problem, and various efforts have been made to prevent it. In this study, we propose a system that can prevent school violence by analyzing data on the frequency of conversations between students, and identify peer relationships. The frequency of conversations between students in the class was quantified using a rating scale questionnaire, and this data was grouped into the appropriate number of clusters using the K-means algorithm. Additionally, the homeroom teacher observed the frequency and nature of conversations between students, and targeted specific individuals or groups for counseling and intervention, with the aim of reducing school violence. Data analysis revealed that the teachers' qualitative observations were consistent with the quantified data based on student questionnaires, and therefore applicable as quantitative data towards the identification and understanding of student relationships within the classroom. The study has potential limitations. The data used is subjective and based on peer evaluations which can be inconsistent as the students may use different criteria to evaluate one another. It is expected that this study will help homeroom teachers in their efforts to prevent school violence by understanding the relationships between students within the classroom.

• Journal of Cadastre & Land InformatiX
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• v.53 no.1
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• pp.83-105
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• 2023

A robot-friendly building certification system was established in 2022 to accommodate the growing number of service robots introduced into buildings. However, this system primarily targeted office buildings, with limitations in applying other functional architectures. To address this problem, we developed a certification model of a robot-friendly environment to extend the existing system to apartment complexes. Using focus group interviews and the analytic hierarchy process, we established 28 evaluating items categorized as (a) architecture and facility design, (b) networks and systems, (c) building operations management, and (d) support for robot activity and other services. These indicators were weighted based on their relative importance within and between categories, resulting in scores ranging from 1 to 18 points and a total of 176 points. According to evaluations with the 28 items, each apartment complex could be graded as "best," "excellent," or "general" based on its total achieved scores. This study is significant, as we present the world's first certification model of a robot-friendly environment for apartment complexes that considers human-robot interactions

• Journal of Korean Library and Information Science Society
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• v.54 no.2
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• pp.23-42
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• 2023

The library tour program is a new type of cultural program that was first introduced and operated by J City, and library tourists travel to specialized libraries in the city according to a set course and experience various experiences. This study aims to build a customized course recommendation model that considers the characteristics of individual participants in addition to the existing fixed group travel format so that more users can enjoy the opportunity to participate in library tours. To this end, the characteristics of library travelers were categorized to establish traveler personas, and library evaluation items and evaluation criteria were established accordingly. We selected 22 libraries targeted by the library travel program and measured library data through actual visits. Based on the collected data, we derived the characteristics of suitable libraries and developed a persona-based library tour course recommendation model using a decision tree algorithm. To demonstrate the feasibility of the proposed recommendation model, we build a mobile application mockup, and conducted user evaluations with actual library users to identify satisfaction and improvements to the developed model.

• Journal of Ginseng Research
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• v.47 no.4
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• pp.534-542
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• 2023

Background: Ginsenoside Rg1, a bioactive component of Ginseng, has demonstrated anti-inflammatory, anti-cancer, and hepatoprotective effects. It is known that the epithelial-mesenchymal transition (EMT) plays a key role in the activation of hepatic stellate cells (HSCs). Recently, Rg1 has been shown to reverse liver fibrosis by suppressing EMT, although the mechanism of Rg1-mediated anti-fibrosis effects is still largely unclear. Interestingly, Smad7, a negative regulator of the transforming growth factor β (TGF-β) pathway, is often methylated during liver fibrosis. Whether Smad7 methylation plays a vital role in the effects of Rg1 on liver fibrosis remains unclear. Methods: Anti-fibrosis effects were examined after Rg1 processing in vivo and in vitro. Smad7 expression, Smad7 methylation, and microRNA-152 (miR-152) levels were also analyzed. Results: Rg1 significantly reduced the liver fibrosis caused by carbon tetrachloride, and reduced collagen deposition was also observed. Rg1 also contributed to the suppression of collagenation and HSC reproduction in vitro. Rg1 caused EMT inactivation, reducing Desmin and increasing E-cadherin levels. Notably, the effect of Rg1 on HSC activation was mediated by the TGF-β pathway. Rg1 induced Smad7 expression and demethylation. The over-expression of DNA methyltransferase 1 (DNMT1) blocked the Rg1-mediated inhibition of Smad7 methylation, and miR-152 targeted DNMT1. Further experiments suggested that Rg1 repressed Smad7 methylation via miR-152-mediated DNMT1 inhibition. MiR-152 inhibition reversed the Rg1-induced promotion of Smad7 expression and demethylation. In addition, miR-152 silencing led to the inhibition of the Rg1-induced EMT inactivation. Conclusion: Rg1 inhibits HSC activation by epigenetically modulating Smad7 expression and at least by partly inhibiting EMT.

• The Korean Journal of Franchise Management
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• v.8 no.3
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• pp.29-37
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• 2017

Purpose - In recent years, research has been conducted on the conflict resolution strategies of the franchise headquarters and the franchisees, but there is a lack of research on the factors of conflict due to the intrinsic structure, such as interdependence or hierarchical relationship, and behavioral analysis to reduce the conflict. In this study, we analyze the relationship between satisfaction and trust formed in the process and result of the business, and the result of action to dissolution intention. Research design, data, methodology - For these purposes, the author developed the proposed model and several hypotheses. In this model, conflict resolution strategies consist of five dimensions such as avoiding, forcing, cooperating, obliging, and compromising strategy. And, this model proposed that onflict resolution strategies are antecedents of procedure quality, behaviour quality and dissolution intention are consequences of conflict resolution strategies. The data were collected from April 1 to April 15, 2013. Because this study examined franchise industries from the franchisee perspective, we contacted franchisee store owner and managers located in Seoul and Gyeonggi Province. Interviewers trained contacted a total of 483 franchisees, and 400 franchisees responded. Out of 400 respondents, 2 respondents were deleted due to missing information. Thus, a total of 398 franchisee were used for this study. he data were analyzed using frequency analysis, confirmatory factor analysis, correlation analysis, and structural equational modeling with SPSS 24.0 and Amos 23.0 statistical program. Results - The findings can be summarized as follows: First, franchisor conflict resolution activities have significant effects on procedure quality. Second, procedure quality has a significant effect on behavior quality. Finally, behavior quality has a significant effect on dissolution intention. Conclusions - In this study, we investigated the relationship between conflict resolution behavior, procedural quality, behavior quality and dissolution intention. As a result, the franchisers should strive to resolve conflicts not only in solving simple problems with franchisees, but also in a longer term perspective. We also found that the procedural aspects of resolving conflicts should not be ignored. If the trust and satisfaction of each other increase during the process of resolving the conflict, it will positively affect the satisfaction and trust in resolving the conflict. This is also because it serves to lower the intention of termination. However, there is a limitation that it is targeted only to the restaurant franchise, and it is necessary to study the conflict resolution behavior depending on the type of conflict.

• Journal of Life Science
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• v.33 no.7
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• pp.574-585
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• 2023

Sarcopenia is a leading cause of increased medical and nursing care costs among the elderly. In Korea, preventive measures for sarcopenia are mostly targeted toward the general elderly population without specific diseases. However, it is also necessary to implement measures for elderly individuals living in nursing homes and hospitals, where the prevalence of sarcopenia is high. Currently, computed tomography and/or magnetic resonance imaging are considered standard diagnostic tools. However, their complexity and time-consuming nature make them unsuitable for clinical use. The exact pathophysiological mechanisms of sarcopenia are unclear, as they involve various molecular biological pathways, including decreased exercise, protein and nutrient intake, changes in testosterone and growth hormone, and inflammation. Sarcopenia symptoms can lead to several diseases, such as osteoporosis, fractures, dementia, diabetes, and cardiovascular disease. Vitamin B deficiency is a significant factor in sarcopenia induction, with B vitamins being directly involved in energy and protein metabolism and nerve function. Vitamin B deficiency can lead to neuromuscular and neurogenic disorders, which often overlap with sarcopenia. Suboptimal intake of B vitamins, malabsorption, and anorexia are common among the elderly. This study aims to provide information on the role of water-soluble B vitamins in preventing and controlling muscle mass loss and deterioration among the elderly with sarcopenia. In addition, we discuss the potential of myokines from the B vitamin family in modulating sarcopenia.

• Industry Promotion Research
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• v.8 no.1
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• pp.103-110
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• 2023

This study targeted KakaoTalk app users, mainly in Seoul and the metropolitan area, and verified the factors that had a significant impact on the intention to continuously use the app through KakaoTalk contents. Among various content characteristics, five variables were used to verify the variables that had the greatest influence on the intention to continue using, and the ones that did not. As a result of testing the five hypotheses, it was found that convenience, enjoyment, informativeness, and perceived usefulness had a significant positive(+) effect on the intention to continue using, but intimacy did not. From this, it can be determined that the majority of users use the app content because it is useful and informative, rather than because they have a sense of familiarity. In this way, the purpose of this study is to provide empirical help to factors closely related to the intention of continuous use in deriving priorities to be considered in the service planning stage as well as in terms of technical design of contents when developing mobile apps in the mobile app industry as a whole and in the field in the future. I want to provide it, but there is a meaning.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.669-676
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• 2023

This study analyzed the relationship between major parameters and numerical analysis results according to various excavations conducted around the urban railway, application of machine learning techniques and verified the scope of influence of the adjacent excavation on the existing urban railway box structure and the appropriateness of the safety area. This study targeted the actual negotiated adjacent excavation works and box structures around the urban railway, and the analysis was conducted on the most representative two-line box structures. The analysis confirmed that the difference in depth of urban railway, excavation depth of adjacent excavation, and depth of underground water level are important parameters, and the difference in excavation depth of adjacent excavation is the parameter that affects the behavior of underground box structures and is an important requirement for setting safety areas. In particular, the deeper the depth of the adjacent excavation work, the greater the effect on the deflection of the underground box structure, and the horizontal separation distance, one of the important requirements for determining the management grade of the existing adjacent excavation work, is relatively small.

• Journal of Food Hygiene and Safety
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• v.38 no.1
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• pp.26-30
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• 2023

In this study, we analyzed the microbial contamination level of ultraviolet sterilizer (UVS) chambers and suggested plans to improve hygiene management. In this study, UVS chambers targeted 98 UVS in some childcare centers in Jeollanam-do, Korea. Total aerobic bacteria and coliform bacteria were tested according to the Korean Food Code. Of the 98 UVS chambers, total aerobic bacteria were detected in 67 (68.4%) and coliform bacteria in 5 (5.1%). Six kinds of food-poisoning bacteria, including Salmonella spp., were not detected, but Bacillus cereus was detected in 1 (2.8%) out of 98 UVS chambers. According to the UV lamp replacement period, the detection rate of total aerobic bacteria was 3 (50%) out of 6 UVS within 3 months, 3 (60%) out of 5 UVS in 3 to 6 months, and 61 (70.1%) out of 87 UVS over 6 months. The detection rate of coliform bacteria according to the UV lamp replacement period was not detected within 6 months, however, they were detected in 5 (5.7%) out of 87 chambers after more than 6 months. The level of microbial contamination in the UVS chambers was higher as the lamp replacement period was longer. Considering these results, it was determined that the UVS chambers should be kept dry and clean, and the UV lamp should be replaced periodically. In addition, it is necessary to provide the staff catering for childcare centers with continuous education regarding the cleaning of UVS chambers and the replacement of UV lamps.