• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.259-264
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• 2001

High-resolution simulations using vortex methods have been performed for simulating unsteady viscous flows around an impulsively started square cylinder. In order to investigate the phenomenon from laminar to transition flow, simulations are performed for Reynolds numbers 25, 50, 150 and 250. At extremely low Reynolds number, flow around a square cylinder is known to separate at the trailing edges rather than the leading edges. With an increase of Reynolds number, the flow separation at the leading edges will be developed. The main flow characteristics of developing recirculation region and separations from leading and trailing edges are studied with the unsteady behavior of the wake after the cylinder starts impulsively. A notable change in the flow evolution is found at Re=150, that is, it is shown that the flow separations begin at both leading and trailing edges of the square cylinder. On the other hand, when Re=250, the strong secondary vorticity from the rear surfaces of the square cylinder increases the drag coefficient as the primary vortex layer is pushed outwards. The comparisons between results of the present study and experimental data show a good consistency.

• 응용통계연구
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• 제28권6호
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• pp.1121-1131
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• 2015

의학이나 사회과학에서 이진 데이터 분석 시 랜덤 절편(random intercept)을 갖는 로지스틱 모형이 유용하게 쓰이고 있다. 지금까지는 이러한 로지스틱 모형에서 랜덤 절편이 정규분포와 같은 모수 모형(parametric model)을 따른다는 가정과 설명변수와 랜덤 절편이 독립이라는 가정 하에 실행된 데이터 분석이 전반적이었다. 그러나 이러한 두 가지 가정은 다소 무리가 있다. 이 연구에서는 설명 변수와 랜덤 절편의 독립성을 가정하지 않고, 비모수 랜덤 절편을 따르는 로지스틱 모형의 방법론을 기존에 널리 쓰인 방법과 비교하여 설명하도록 한다. 케냐의 초등학생들의 영양 섭취 및 질병의 발병을 조사한 데이터에 이 방법을 적용하였다.

• 한국정보전자통신기술학회논문지
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• 제3권1호
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• pp.57-62
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• 2010

본 논문에서는 취업정보를 원활하게 접할 수 있는 환경을 제공하기 위한 구직 구인 정보를 구축하기 위하여 2가지를 제시하였다. 첫째, 취업사이트를 구축하기 위해 실 사례를 대상으로 데이터베이스 코드 확장 기준, 카테고리화 기준, 그리고 ERD (Entity Relation Diagram)를 설계하였다. 둘째, 친숙성이 강한 레이블 규칙을 위한 소수 레이블링 기준을 정의하였다. 따라서, 데이터베이스를 설계 및 구축하는데 있어 일정한 규칙을 체계적으로 적용함으로써 데이터베이스 구축 운영시 일관성과 효율성을 높이고 응용프로그램 개발 및 운영의 편의를 제공할 수 있으며 제안한 코드 확장 규칙 정의는 국내외 구인 구직 정보제공 기관에 표준화가 가능하다.

• 대한교통학회지
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• 제23권5호
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• pp.35-45
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• 2005

자동 과속 단속 시스템은 중요한 교통사고 예방 대책의 하나이다. 운전자는 자동과속단속시스템 설치 지점 부근에서 속도를 감속하고 설치지점 통과 후 다시 가속한다. 따라서 단속의 목적을 둔 과속단속시스템은 충분한 안전 효과를 발휘하는데 한계가 있으며, 속도 관리 개념의 설치 방안이 마련될 필요가 있다 본 연구는 연속된 도로 구간을 주행하는 운전자의 주행속도 변화를 일정 범주 내로 유지시키는 도로 설계 일관성 개념을 과속단속시스템의 설치위치 선정에 적용하였다. 또한 과속단속시스템도 도로 곡선부 등 선형 요소와 마찬가지로 운전자의 주행속도를 변화시키는 설계 요소의 하나로 간주하고, 설계 일관성 개념 및 평가기준을 동일하게 적용한 설치 방안을 제안하였다.

• 대한가정학회지
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• 제49권6호
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• pp.85-94
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• 2011

The purpose of this study was to validate the Korean Family Support & Challenge Questionnaire (K-SCQ), which is designed to assess family complexity in Children. There were 258 pre-test participants in this study and 498 senior students who were in elementary school. Results from the pre-test suggested us to use Likert scale over a dichotomous agree or disagree scale and positively items over negative ones. Results of the confirmatory factor analysis showed that the two factor structure (family support and challenge) of the SCQ fits well for Korean students. The K-SCQ has also good internal consistency. Further analysis was performed to explore the relationships between four family types based on K-SCQ and children's well-being and flow experience. It showed that the children in a high support/high challenge family had the highest emotional well-being, psychological well-being, and flow experience. These results suggest that the complex family characterized by high support and challenge has strong and positive impact on the children's quality of life.

• Journal of Genetic Medicine
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• 제6권2호
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• pp.121-130
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• 2009

자궁내막증의 유전 소인을 감안하였을 때 관련 유전자 다형성 조사는 매우 중요한 의미를 갖는다. 현재까지 약 30여개의 한국인을 대상으로 한 결과를 조사하여 자궁내막증과 특정 유전자내 다형성과의 연관성을 파악하고자 하였다. 가장 의미있는 유전자 다형성은 한국인 자궁내막증 환자에서의 GSTT1, AhRR, ER-alpha, VEGF, AHSG, 그리고TNF-alpha 유전자 다형성이다. 다만 결과가 부분적으로 상충되기도 하여 추가 연구을 통해 결과 재현성을 증명해야 할 것으로 사료된다. 마지막으로 자궁내막증을 대상으로 유전자 연구에서의 추후 연구 방향을 제시하고자 한다.

• The Journal of Korean Physical Therapy
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• 제22권3호
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• pp.37-44
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• 2010

Purpose: The purpose of this study was to describe the functional (mobility, self-care, social ability) and health-related quality of life in children with cerebral palsy (CP). Methods: A cross- sectional survey of 202 children with CP, mean age $5.91{\pm}1.57$ years, was carried out using the Gross Motor Function Classification System (GMFCS), Gross Motor Function Measure (GMFM), Pediatric Evaluation of Disability Inventory (PEDI), and Child Health Questionnaire (CHQ). Results: The functional assessment of children with CP showed that a more severe GMFCS level was associated with lower functional abilities (p<0.05). The health-related quality of life assessment showed that psychosocial well-being was less impaired than physical well-being. The internal consistency of the three instruments was satisfactory (cronbach's ${\alpha}$>0.80). The three different scales were correlated from moderate to strong (r=0.44 to 0.92). It was also found that mobility, tone distribution, and the parents' education level exerted a significant effect on the quality of life of children with CP (p<0.05). Conclusion: These findings suggest that children with CP have reduced function and quality of life and these are influenced by various factors. However, planning and application of various task-oriented functional interventions to childhood CP may be useful.

• 동의신경정신과학회지
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• 제26권2호
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• pp.181-190
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• 2015

Objectives: The purpose of this study was to analyze the Validity and Reliability of the Five Facet Mindfulness Questionnaire (FFMQ), using mindfulness meditation performed before and after. Methods: The study was conducted with 87 students at the university of Korean medicine who provided informed consent. The demographic characteristics and FFMQ were analyzed with regard to their validity and reliability on the effect of mindfulness using SPSS (Statistical Package for the Social Sciences, IBM, United States of America) 21.0 Version. Results: 1. The reliability and factor analysis of FFMQ : The five sub-factors of mindfulness showed strong internal consistency (Cronbach's ${\alpha}$ >.70). 2. Correlation analysis of the sub-factors in pre-FFMQ showed a positive correlation between Nonreactivity and Awareness, Nonreactivity and Scribing, Nonreactivity and Nonjudging, Nonreactivity and Total score, Observing and Scribing, Observing and Total score, Awareness and Nonjudging, Awareness and Total score. 3. Correlation analysis of the sub-factor in post-FFMQ showed a positive correlation between Scribing and Nonreactivity, Scribing and Observing, Scribing and Awareness, Awareness and Nonjudging. In contrast, Observing had a negative correlation with Nonjudging. Conclusions: The results of the study reconfirmed that FFMQ was useful as a reliable and valid tool for measuring mindfulness meditation.

• Smart Structures and Systems
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• 제14권1호
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• pp.17-37
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• 2014

In this study, four widely accepted and used variants of Evolution Strategies (ES) are adapted and applied to the output-error state-space identification problem. The selection of ES is justified by prior strong indication of superior performance to similar problems, over alternatives like Genetic Algorithms (GA) or Evolutionary Programming (EP). The ES variants that are being tested are (i) the (1+1)-ES, (ii) the $({\mu}/{\rho}+{\lambda})-{\sigma}$-SA-ES, (iii) the $({\mu}_I,{\lambda})-{\sigma}$-SA-ES, and (iv) the (${\mu}_w,{\lambda}$)-CMA-ES. The study is based on a six-degree-of-freedom (DOF) structural model of a shear building that is characterized by light damping (up to 5%). The envisaged analysis is taking place through Monte Carlo experiments under two different excitation types (stationary / non-stationary) and the applied ES are assessed in terms of (i) accurate modal parameters extraction, (ii) statistical consistency, (iii) performance under noise-corrupted data, and (iv) performance under non-stationary data. The results of this suggest that ES are indeed competitive alternatives in the non-linear state-space estimation problem and deserve further attention.

• 한국치위생학회지
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• 제20권5호
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• pp.545-559
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• 2020

Objectives: The purpose of this study was to systematically analyze and examine the relationship between the number of lost teeth and quality of life (QoL) among elderly. Methods: Papers published in Korean and English between 2000 and 2020 were searched. Relevant papers were selected by two independent readers according to predefined exclusion criteria. Quality assessment and consistency tests were conducted using ROBIS. Results: Twelve of the 854 studies were targeted, and the analysis confirmed that tooth loss was related to a decrease in the QoL in 11 studies. Tooth loss negatively affected the QoL among the elderly. However, one study indicated that the QoL and number of teeth were not related. Rather, dry mouth affected the QoL, and cavities caused by oral dryness led to tooth loss. Most of the selected studies indicated that the QoL of elderly individuals with a single tooth was higher than that of those with no teeth. Conclusions: This study provides strong evidence that tooth loss in the elderly is associated with impairment of QoL.