• Title/Summary/Keyword: literature review

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Screening Cases of Potential Extreme Natural Hazards Based on External Event Analysis of Operational Nuclear Power Plants (가동 원전의 외부사건 분석에 기반한 잠재적 극한자연재해의 선별)

  • Chung, Gil-Young;Kim, Gi-Bae;Park, Hyun-Sung;Park, Hyung-Kui ;Choun, Young-Sun;Chang, Soo-Hyuk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.6
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    • pp.699-708
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    • 2023
  • Nuclear power plants (NPPs) consider possible external events, including natural hazards, during the design phase to ensure safe operation. However, in recent years, due to the increasing probability of natural hazards exceeding the design, a careful review of extreme natural hazards and unforeseen external events during the design phase has become necessary. In this study, the objective was to screen potential extreme natural hazards at NPP sites in Korea. Initially, we investigated and analyzed the characteristics of NPP sites and the events caused by external hazards. Furthermore, we analyzed existing literature and research data to establish screening procedures and criteria that suit the actual conditions of domestic NPPs. Based on these criteria and data, we conducted qualitative screening for each NPP site and identified potential extreme natural hazards through quantitative screening and walkdown. As a result of the screening, in addition to internal flooding caused by heavy rain, wind pressure and extreme air pressure caused by extreme winds were screened as potential extreme natural hazards common to all sites. Additionally, at the Kori site, storm surge was selected as the most significant potential extreme natural hazard.

A Design Perspective on Instagram Addiction (디자인적 관점에서 바라본 인스타그램 중독)

  • Changhee Han
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.339-345
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    • 2023
  • Design exists behind technology. Design is intertwined with the needs of daily life and market structures, and while dealing with technology, it can become insensitive to its meaning. Unlike other social media platforms, Instagram consists of image-based content. The purpose of this study is to examine the addictive design of Instagram. Furthermore, we discuss the ethical responsibilities that designers must have. A theoretical framework for understanding Instagram design is established through a review of major domestic and international literature that has been previously studied. Understand the history, structure, and functions of Instagram and identify Instagram designs that promote social media addiction. In this study, we introduced the mechanism by which Instagram promotes user addiction through design issues. (1) Pull-to-Refresh (2) Red color in push alarm (3) Profile photo border expression in Instagram Story. This design stimulates users' social desires and FOMO, forming the structure of obsessive Instagram usage habits. Instagram is an example that forces us to reconsider the ethical role of design and designers along with the advancement of technology. In today's world, the intrinsic value of what they create, including our society and life itself.

Application of Multiple Linear Regression Analysis and Tree-Based Machine Learning Techniques for Cutter Life Index(CLI) Prediction (커터수명지수 예측을 위한 다중선형회귀분석과 트리 기반 머신러닝 기법 적용)

  • Ju-Pyo Hong;Tae Young Ko
    • Tunnel and Underground Space
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    • v.33 no.6
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    • pp.594-609
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    • 2023
  • TBM (Tunnel Boring Machine) method is gaining popularity in urban and underwater tunneling projects due to its ability to ensure excavation face stability and minimize environmental impact. Among the prominent models for predicting disc cutter life, the NTNU model uses the Cutter Life Index(CLI) as a key parameter, but the complexity of testing procedures and rarity of equipment make measurement challenging. In this study, CLI was predicted using multiple linear regression analysis and tree-based machine learning techniques, utilizing rock properties. Through literature review, a database including rock uniaxial compressive strength, Brazilian tensile strength, equivalent quartz content, and Cerchar abrasivity index was built, and derived variables were added. The multiple linear regression analysis selected input variables based on statistical significance and multicollinearity, while the machine learning prediction model chose variables based on their importance. Dividing the data into 80% for training and 20% for testing, a comparative analysis of the predictive performance was conducted, and XGBoost was identified as the optimal model. The validity of the multiple linear regression and XGBoost models derived in this study was confirmed by comparing their predictive performance with prior research.

A Literature Review on Asthma and Chronic Obstructive Pulmonary Disease Among Domestic and Overseas Farmers (국내외 농업인 천식 및 만성 폐쇄성 폐질환에 관한 고찰)

  • Siyoung Kim;Seongyong Yoon;Jinseok Kim;Seong-yong Cho;Hyun Woo Park;Daehwan Kim;Gayoung Kim;Jisoo Kang;Kyungsu Kim;Dongphil Choi;Seok-Ju Yoo
    • Journal of agricultural medicine and community health
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    • v.48 no.4
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    • pp.251-261
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    • 2023
  • Objective: Farmers are known to have high prevalence of asthma and chronic obstructive pulmonary disease(COPD). This study aims to investigate the current status of asthma and COPD in domestic and foreign farmers with the ultimate goal of raising awareness of asthma and COPD among farmers and contribute to supporting evidence for the prevention of respiratory diseases in farmers. Methods: The study utilized data from the "Farmer's Occupational Disease Survey," conducted by the Rural Development Administration, to determine the prevalence of respiratory diseases in domestic farmers. The prevalence of asthma and COPD in overseas farmers was evaluated by researching other foreign studies and articles. Results: The prevalence of asthma and COPD in domestic farmers was less than of foreign farmers'. The prevalence of asthma in domestic farmers was high as upto 8.4% and COPD upto 5.5%. Studies from Europe and America showed prevalence of asthma in farmers high as upto 14.8% and COPD upto 17.1%. Conclusions: This study conducted an investigation using the 'Survey on Occupational Diseases and Injuries in Farmers to understand the current status of asthma and COPD in domestic farmers. Due to a lack of relevant domestic research, we examined and compared with the research results on asthma and COPD among overseas farmers. Further research is necessary and preventive measures for respiratory diseases need to be developed.

The Mediating Effect of Grit in the Relationship between pPCK and ePCK Perceived by Teachers in Elementary School Science Classes (초등학교 과학 수업에서 교사가 인식하는 pPCK와 ePCK 사이의 관계에서 그릿의 매개효과)

  • Chae, Yoojeong;Lee, Kiyoung;Park, Jaeyong
    • Journal of Korean Elementary Science Education
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    • v.43 no.1
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    • pp.95-107
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    • 2024
  • In this study, we explored the mediating effect of grit in the relationship between elementary school science teachers' perceived personal pedagogical content knowledge (pPCK) and enacted pedagogical content knowledge (ePCK). Drawing on insights from a review of the literature, we developed a research hypothesis model that set pPCK, ePCK, and grit as latent variables. Pearson correlation was conducted to examine the interrelationships among the latent variables. Structural equation modeling (SEM) was then employed to analyze the model fit. Additionally, bootstrap analysis was performed to specifically investigate the mediating effect of grit in the relationship between pPCK and ePCK. The Pearson correlation analysis indicated statistically significant correlations among the measurement variables. Meanwhile, the SEM analysis revealed that the measurement model aligned with the research hypothesis model. Furthermore, the bootstrap analysis demonstrated that grit had a statistically significant mediating effect in the relationship between elementary school science teachers' perceived pPCK and ePCK. These findings quantitatively examine the importance and impact of grit in the teacher expertise domain, providing valuable insights for the development of teachers' expertise and teacher education research within elementary school science classes.

Opportunity or Threat?: Case Study of an Arts Entrepreneur Responding to Gentrification (위협인가 기회인가? 젠트리피케이션에 대응하는 예술기업가 연구 - 문래문화살롱 사례를 중심으로 -)

  • Lee, JooEun;Na, Hea Young;Chang, WoongJo
    • Korean Association of Arts Management
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    • no.50
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    • pp.147-175
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    • 2019
  • Gentrification is the process by which a working class or other disadvantaged area of a city changes into a middle class residential or commercial district. Gentrification, which has received much attention in arts management in recent years as part of a concern with urban regeneration, carries a generally negative connotation. In this paper, we interrogate this negative view of gentrification to explore ways arts entrepreneurship can convert the perceived threat of gentrification into opportunity. To this end, we examine the Mullae Cultural Salon in the gentrifying district of the Mullae Creative Village. Through a literature review of gentrification and arts entrepreneurship, we propose seven elements of art entrepreneurs responding to gentrification as an analytic framework for research. Our findings indicate that arts entrepreneurs were able to extend the maturity phase of gentrification and thus enhance the cultural and artistic value of the region for other artists and arts entrepreneurs.

Effectiveness of Two-dose Varicella Vaccination: Bayesian Network Meta-analysis

  • Kwan Hong;Young June Choe;Young Hwa Lee;Yoonsun Yoon;Yun-Kyung Kim
    • Pediatric Infection and Vaccine
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    • v.31 no.1
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    • pp.55-63
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    • 2024
  • Purpose: A 2-dose varicella vaccination strategy has been introduced in many countries worldwide, aiming to increase vaccine effectiveness (VE) against varicella infection. In this network meta-analysis, we aimed to provide a comprehensive evaluation and an overall estimated effect of varicella vaccination strategies, via a Bayesian model. Methods: For each eligible study, we collected trial characteristics, such as: 1-dose vs. 2-dose, demographic characteristics, and outcomes of interest. For studies involving different doses, we aggregated the data for the same number of doses delivered into one arm. The preventive effect of 1-dose vs. 2-dose of varicella vaccine were evaluated in terms of the odds ratio (OR) and corresponding equal-tailed 95% confidence interval (95% CI). Results: A total of 903 studies were retrieved during our literature search, and 25 interventional or observational studies were selected for the Bayesian network meta-analysis. A total of 49,265 observed individuals were included in this network meta-analysis. Compared to the 0-dose control group, the OR of all varicella infections were 0.087 (95% CI, 0.046-0.164) and 0.310 (95% CI, 0.198-0.484) for 2-doses and one-dose, respectively, which corresponded to VE of 69.0% (95% CI, 51.6-81.2) and VE of 91.3% (95% CI, 83.6-95.4) for 1- and 2-doses, respectively. Conclusions: A 2-dose vaccine strategy was able to significantly reduce varicella burden. The effectiveness of 2-dose vaccination on reducing the risk of infection was demonstrated by sound statistical evidence, which highlights the public health need for a 2-dose vaccine recommendation.

The Effect of Marketing Mix Factors on Sales: Comparison of Superstars and Long Tails in the Film Industry (마케팅믹스 요소가 매출액에 미치는 영향: 영화산업에서 슈퍼스타와 롱테일의 비교)

  • Jung-Won Lee;Choel Park
    • Information Systems Review
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    • v.24 no.2
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    • pp.1-20
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    • 2022
  • Researchers are making contradictory claims through the concept of superstars and long tails about how the development of IT technology affects demand distribution. Unlike previous studies that focused on changes in demand from a macro point of view, this study explored whether the relationship between a company's marketing activities and consumer response differs depending on the product location (i.e., superstar vs. long tail) from a micro point of view. Based on the marketing mix framework, hypotheses were developed based on the relevant literature. In the case of empirical analysis, 2,835 daily data from 63 Korean films were tested using the quantile regression method. As a result of the analysis, it was found that the influence of marketing mix factors on sales varies depending on the location of the product. Specifically, the appeal breadth of the film and the effect of owned media are enhanced in superstar products, and the effect of acquisition media in long-tail products is enhanced and the negative effects of competition are mitigated. Unlike previous studies that focused on macroscopic changes in demand distribution, this study suggested marketing activities suitable for practitioners through microscopic analysis.

A Study on the Buddhist Sculptures of Modern Buddhist Artist SeokhaSichan (근대기 금어(金魚) 석하시찬(石霞施讚)의 불상 연구)

  • LEE Jumin
    • Korean Journal of Heritage: History & Science
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    • v.57 no.2
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    • pp.52-78
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    • 2024
  • This study analyzes the sculptural art of SeokhaSichan(石霞施讚, 1893-1958), a significant figure in modern Korean Buddhist art, to re-examine his contributions and standing in the history of Korean Buddhist art. Sichan expanded the boundaries of modern Korean Buddhist art by developing a unique style based on the traditional sculptural techniques he learned from his mentor, Wanho Nakhyeon (玩虎洛現, 1869~1933). This study explores Sichan's artistic development, focusing on his artistic characteristics and sculptural evolution. Sichan's early works are characterized by small sculptures modeled after the main Buddha of Seokguram Grotto and heavily influenced by his mentor, WanhoNakhyeon. In his later works, notable features include a sense of massive volume, larger scale, upright postures, integration of the Buddha statue with its pedestal, and decorative treatment of drapery. These changes are interpreted as Sichan's response to social changes and his reflection of inner contemplation and artistic exploration in his works. This study reveals the influences of Wanho Nakhyeon, collaborations with Toewon Woneil(退雲圓日, 1877~1939), interactions with patron Kim Jiseonghwa(金至誠華), and master-disciple relationship with successor Geumchun Seongpil(金春性必) through literature review and newly discovered works by Sichan. His works and his artistic evolution are pivotal milestones in the history of modern Korean Buddhist sculpture, demonstrating a unique integration of traditional and modern aesthetics. This study provides valuable insights into how Sichan's artistic legacy was inherited and developed by subsequent generations and offers crucial materials for the study of modern Korean Buddhist sculpture history.

Conceptual Definition and Types of Reflective Thinking on Science Teaching: Focus on the Pre-service Science Teachers (과학 수업에 대한 반성적 사고의 개념적 정의와 유형: 예비 과학교사를 중심으로)

  • Park, Mi-Hwa;Lee, Jin-Seong;Lee, Gyoung-Ho;Song, Jin-Woong
    • Journal of The Korean Association For Science Education
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    • v.27 no.1
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    • pp.70-83
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    • 2007
  • Reflection in teacher education is one reform effort that has taken hold in many teacher preparation programs. However, how to define it and how to foster it in a teacher's education are problematic issues. In this study, on the basis of literature review, science teachers' reflective thinking is defined as a process of thinking that deliberates on alternatives to solve conflict between one's previous knowledge/belief/practice and internal/external factors in science teaching context. Based on this definition, three types of science teachers' reflective thinking (i.e. technical reflection, professional reflection and critical reflection) were proposed. In addition, a framework of classifying the reflective thinking's types was also developed. To investigate science teachers' reflective thinking, two pre-service science teachers who majored in physics education participated in this study. The participants presented the monthly report on reflective practice, pre/post questionnaire, and education practicum journals. Individual interviews with them were conducted before and after their teaching activities. From the analysis of the data, it was possible to categorize the reflective thinking of the participants into three types. The major type of their reflective thinking was the technical reflection. However, it was difficult to find examples of the critical reflection.