• 한국염색가공학회지
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• 제27권4호
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• pp.327-333
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• 2015

This paper aims to manufacture nonwoven fabrics by wet-laid technology using Vectran$^{(R)}$ one of the highly favoured high-performace fiber. In previous study, a novel evaluation on fiber dispersion was studied to select optimum surfactant by the need for the control of fiber dispersion in water with reference to wet-laid nonwoven technology. 3 Types of sulfonate anionic surfactants were chosen and added in a stage of agitation to improve dispersion behavior of fibers in water. It was observed that the state of fiber dispersion in water affected various properties of nonwovens, including appearance, physical properties, and mechanical properties. Nonwoven added SDBS was uniform in web structure, thickness and weight. Its average pore was small in size and consisted of fine pores and the value of porosity was high. Further, the difference of tensile value between 2 directions was the least. Consequentially, as the dispersion behavior of fiber increases, nonwoven shows more balanced and uniform physical properties in all directions.

• 정보처리학회논문지B
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• 제11B권5호
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• pp.587-596
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• 2004

최근들어 오디오, 비디오와 이미지 같은 다양한 디지털 멀티미디어 데이터의 인덱싱, 브라우징과 질의를 위한 새로운 형태의 시스템이 개발되었다. 이러한 시스템은 각 미디어 스트림을 실제 물리적 이벤트에 따라서 작은 유닛단위로 나누고, 물리적 이벤트들을 검색을 위해서 효율적으로 인덱스화 시킨다. 본 논문에서는 오디오-비주얼 데이터의 분석과 세그멘테이션을 위해서 각 데이터가 가지고 있는 오디오, 이미지, 비디오 특징을 이용하는 새로운 방법을 사용한다. 이것은 이미지나 비디오만을 분석했던 이전의 방법들을 문제점을 해결 할 수 있다. 본 논문에서는 이와 같은 방법을 이용하여 XCRAB이라고 불리는 웹 기반 멀티미디어 검색 시스템을 구현하였고, 성능평가를 위해서 여러가지 질의의 조합을 이용하여 실험을 하였다.

• 지역사회간호학회지
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• 제29권4호
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• pp.476-487
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• 2018

Purpose: The present study is focused on understanding weight perception related with individual- and school-level multifactorial origins, underestimated and overestimated respectively, in normal body weight adolescents. Methods: Using the 2017 Korea Youth Risk Behavior Web-based Survey data of 45,902 students from 799 secondary schools, a multilevel multinomial logistic regression analysis was performed where adolescents (level1) were nested within schools (level 2). Results: At the school level, the average school body mass index (BMI, $kg/m^2$) and physical education were associated with weight perception among both boys and girls. In boys, geographic areas were associated with weight underestimation. At the individual level, perceived economic status, weekly allowance, BMI ($kg/m^2$), smartphone usage time (hrs/day) and perceived stress were associated with weight perception among both boys and girls. Age, paternal education, academic achievement and alcohol use were associated with weight perception among girls, while part-time job and physical activity were associated with weight perception among boys. Conclusion: Our findings underscore the importance of individual- and school-level environments in developing correct weight perception and have implications for school health education to establish healthy lifestyle behaviors for all adolescents.

• 한국정보시스템학회지:정보시스템연구
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• 제28권3호
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• pp.39-58
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• 2019

Purpose A digital twin is a digital replication of a physical system. Gartner identified the digital twin as one of the Gartner Top 10 Strategic Technology Trend for three years from 2017. The rapid development of the digital twin market is expected to bring about innovation and change throughout society, and much research has been done recently in academia. In this research, we tried to explore the main research trends for digital twin research. Design/methodology/approach We collected the digital twin research from Web of Science, and analyzed 804 articles that was published during time span of 2010-2018. A total of 41 key authors were selected based on the frequency of citation. We created a co-citation matrix for the core authors, and performed multivariate analysis such as cluster analysis and multidimensional scaling. We also conducted social network analysis to find the influential researchers in digital twin research. Findings We identified four major sub- areas of digital twin research: "Infrastructure", "Prospects and Challenges", "Security", and "Smart Manufacturing". We also identified the most influential researchers in digital twin research: Lee EA, Rajkumar R, Wan J, Karnouskos S, Kim K, and Cardenas AA. Limitation and further research suggestion were also discussed as a concluding remarks.

• 한국학교보건학회지
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• 제33권3호
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• pp.139-147
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• 2020

Purpose: The study aimed to identify factors affecting unintentional injuries at school focusing on violent experiences in adolescents. Methods: The study used the raw data of the Korea Youth Risk Behavior Web-based Survey (2019). A total of 60,040 students were included in the analysis. Descriptive statistics, χ2 test, and multiple logistic regression were performed, using SPSS version 25.0. General characteristics, gender, school, academic achievement, living with family, socioeconomic status, vigorous physical activity, perceived stress, sleep satisfaction, high caffeine drinking, risky alcohol drinking, smoking, sexual experience, drug use, and safety education, were adjusted for and the relationship between unintentional injuries and violence was analyzed. Results: The results showed 2.4% of the adolescents had experienced violence and 24.7% had suffered unintentional injuries. Violent experiences had a significant effect on unintentional injuries among adolescents. Injuries were 1.93 times higher among adolescents who had experienced violence. Gender, school levels, high-intensity physical activity, stress, sleep satisfaction, high caffeine drinks, dangerous drinking, drug use, and safety education were associated with unintentional injuries among adolescents. Conclusion: Adolescents at high risk of suffering violence and injuries should be identified and assessed preemptively. In addition, it is necessary to implement systematic school health-centered safety education programs in order to prevent violence and injuries.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제11권3호
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• pp.91-98
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• 2022

최근 가상공간과 물리공간이 디지털 융합된 메타버스에 대한 관심이 높아지면서 물리공간에서의 많은 활동이 웹 기반의 가상공간에서 이루어질 전망이다. 따라서 분산 식별자 기반 가상공간 환경에서 사생활과 상호 신뢰를 확보할 수 있는 자기주권 신원시스템에 대한 연구가 요구된다. 본 논문에서는 분산 식별자 기반 자기주권 신원시스템을 위해 Hyperledger Indy와 DIDComm 오픈 소스를 기반으로 분산 식별자, 비대칭 키, DID 문서를 생성하여 블록체인과 지갑에 등록하는 절차, DIDComm 메시지로 구성된 신뢰할 수 있는 통신 방법을 개발하고 검증하였다. 이는 통신 참여자 간의 신뢰를 위한 추가적인 정보 교환 및 검증 가능한 자격증명을 교환하여 서로를 검증하는데 활용이 가능하다

• 항공우주의학회지
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• 제31권2호
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• pp.38-44
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• 2021

Purpose: This study aimed to identify the prevalence of fatigue and its associated factors leading to the fatigue among Korean commercial airline pilots. Methods: An anonymous, web-based questionnaire collecting data on sleep related characteristics was completed by airline pilots. The final 1,029 samples of completed questionnaires were analyzed. The association of the risk factors with fatigue was determined using logistic regression analysis. Results: The prevalence of fatigue was 60% (Fatigue Severity Scale index≥3.2), disturbed sleep 28% (Pittsburgh Sleep Quality Index≥9), daytime sleepiness 17% (Epworth Sleepiness Scale≥10), and sleep apnea (Berlin Questionnaire≥2) 11%. The fully adjusted logistic regression showed that quality of life (odds ratio [OR]=0.16, confidence interval [CI]=0.11-0.24), daytime sleepiness (OR=1.26, CI=1.18-1.34), sleep quality (OR=1.44, CI=1.29-1.61), mental workload (OR=1.10, CI=1.05-1.14), vigorous physical activity (OR=0.82, CI=0.72-0.92), late starts (OR=1.25, CI=1.06-1.46) and average weekly flying hours (OR=1.02, CI=1.00-1.03) were associated with higher levels of fatigue. Conclusion: Lower quality of life, disturbed sleep, more subjective sleepiness, shorter sleep duration, higher mental workload, less vigorous physical activity, frequent late starts, and longer flying hour were shown to be risk factors for fatigue in airline pilots. These findings should be taken into account in the development of sleep and fatigue countermeasures for airline pilots.

• 산경연구논집
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• 제13권11호
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• pp.47-64
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• 2022

Purpose: This study's goal is to investigate how perceived risk of Japanese electronic product affect the negative emotion and the avoidance intentions. In addition, this is difference in the effect of perceived risk on negative emotions and avoidance intentions according to the presence or absence of substitutes. Research design, data and methodology: Perceived risks of Japan products are decided by four dimensions, they are economic risk, social risk, psychological risk and physical risk. The reach model is made by the theory of risk-avoid. We requested this survey to 5808 customers by panel and web site, received 559 replied. We used 528 questionnaires excluding unreliable data. For the analysis, smart PLS is used. Results: Psychological risk has influence on negative emotion and avoidance intension. Social risk and physical risk affected negative emotion, but did not directly affect avoidance intention. Economic risk affects avoidance intension, but it has no effect of negative emotion. The existence of Japanese products' substitute only effects the relationship of economic risk and avoidance intention. Conclusions: Korean consumers behavior their buying and using of Japan product as financial benefit and satisfaction, not only risk. It is suggested that Korean company should make and develop unique product with good price.

• Physical Therapy Rehabilitation Science
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• 제12권2호
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• pp.115-122
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• 2023

Objective: A previous study reported that cardiovascular training (CT) decreased interleukin-6 (IL-6), a pro-inflammatory cytokine with bidirectional effects. However, because of conflicting results of increasing and decreasing IL-6 levels in stroke patients, it is essential to clarify the effects of CT on IL-6 levels in this population. Therefore, this review aimed to investigate the effects of CT on IL-6 levels in stroke patients through a meta-analysis of randomized controlled trials (RCTs), synthesizing and analyzing the effects qualitatively and quantitatively. Design: A systematic review and meta-analysis of randomized controlled trials. Methods: In this review, conducted in April 2023, electronic databases (Web of Science, CINAHL, Embase, MEDLINE, Google Scholar) were searched to ascertain the effects of CT on IL-6 levels in stroke patients. For qualitative evaluation, ReVMan, provided by the Cochrane Group, was used, and for quantitative evaluation, a random-effects model and SMD (Standardized Mean Difference) were used. Results: Three RCTs measured IL-6 in 117 patients with stroke. The experimental group to which CT was applied showed no significant change compared to the control group.The result of analysis using the random effect model is SMD=-0.23; 95% confidence interval, -0.66 to 0.20. Conclusions: CT does not affect IL-6 levels in stroke patients. These results suggest that CT can be applied regardless of its positive or negative effect on IL-6 levels in stroke patients.

• Physical Therapy Rehabilitation Science
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• 제13권2호
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• pp.196-204
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• 2024

Objective: Cortical Visual Impairment (CVI) is a leading cause of pediatric blindness and the most common form of pediatric visual disability, particularly prevalent among children with cerebral palsy (CP). This systematic review synthesizes the latest research on various interventions for managing CVI, focusing on studies published in the last decade. Design: A systematic review Methods: A comprehensive search was conducted in March 2024 across several databases including MEDLINE, CINAHL, Embase, and Web of Science. Studies were selected based on inclusion criteria set under the PICOSD framework and were limited to those involving human subjects, published in English, and conducted within the past ten years. The selected studies included randomized controlled trials, observational studies, and case reports focusing on rehabilitation, therapy, and surgical interventions for CVI. Results: Out of 221 studies screened, 5 met the inclusion criteria and were reviewed in detail. These studies covered a range of interventions including physiotherapy, sensory integration training, visual training programs, neuromotor rehabilitation, and surgical procedures aimed at improving visual function and overall quality of life for CVI patients. Conclusions: The studies demonstrate the potential benefits of structured, early intervention programs that incorporate family involvement and are tailored to the unique needs of children with CVI. However, there remains a significant need for further research to establish evidence-based practices in this field.