• Title/Summary/Keyword: Strong consistency

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The Early Stage Behavior of Unsteady Viscous Flows past an Impulsively Started Square Cylinder (급 출발하는 정방실린더 후류의 비정상 점성유동의 초기거동)

  • Jin, Dong-Sik;Jung, Jae-Hoon;Ahn, Cheol-O;Lee, Sang-Hwan
    • Proceedings of the KSME Conference
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    • 2001.06e
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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.

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Semiparametric Approach to Logistic Model with Random Intercept (준모수적 방법을 이용한 랜덤 절편 로지스틱 모형 분석)

  • Kim, Mijeong
    • The Korean Journal of Applied Statistics
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    • v.28 no.6
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    • pp.1121-1131
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    • 2015
  • Logistic models with a random intercept are useful to analyze longitudinal binary data. Traditionally, the random intercept of the logistic model is assumed to be parametric (such as normal distribution) and is also assumed to be independent to variables. Such assumptions are very strong and restricted for application to real data. Recently, Garcia and Ma (2015) derived semiparametric efficient estimators for logistic model with a random intercept without these assumptions. Their estimator shows the consistency where we do not assume any parametric form for the random intercept. In addition, the method is computationally simple. In this paper, we apply this method to analyze toenail infection data. We compare the semiparametric estimator with maximum likelihood estimator, penalized quasi-likelihood estimator and hierarchical generalized linear estimator.

A Study of Label Intimacy Applied by Applicant's Code-Expansion Rule (구직자 코드확장 규칙을 적용한 레이블 친숙성 연구)

  • Yang, Seung-Hae;Jeong, Eun-Hee;Lee, Byung-Kwan
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.3 no.1
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    • pp.57-62
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    • 2010
  • This paper proposes two methods for the construction of job offer and job hunting information in order to supply an environment that can easily connects to job hunting information. First, the database expansion, category rules and ERD(Entity Relation Diagram) are designed for the construction of job hunting site with real example. Second, the prime number labeling rules are designed for the strong intimacy of label rules. Therefore, according to using the systematic and regular rules when we design and construct a database, the consistency and efficiency are improved in the database being constructed and being operated. And the convenience of application program development and operation are easily provided. In addition, the proposed code-expansion rule can be defined and be standardized in the domestic and foreign job offer and job hunting information provision agency.

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A Study on the Installation of the Automated Speed Enforcement Camera for the Effectiveness (자동 과속단속시스템의 효과 증진을 위한 설치 방안 연구)

  • Kim, Yong-Seok;Cho, Won-Bum
    • Journal of Korean Society of Transportation
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    • v.23 no.5 s.83
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    • pp.35-45
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    • 2005
  • The speed enforcement camera has been regarded as one of the most important safety countermeasures. Drivers decelerate in front of the speed enforcement camera and gain speed up after passing the camera. So there is a strong need to develop the method how to place the camera to overcome this problem. This study applied the concept of design consistency to the installation of the camera, so speed difference along the road sections should be controlled within the predetermined boundary. Specially, this study also regarded camera as the one of the elements of the road alignments which can change the speed of drivers abruptly, and suggested the way to put this concept into the selection of the placement of the camera.

Validity of a Korean Family Support & Challenge Questionnaire (한국판 가족 후원.자극 척도(K-SCQ)의 타당화)

  • Lee, Hwa-Sun;Choe, In-Soo
    • Journal of the Korean Home Economics Association
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    • v.49 no.6
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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.

Genetic Polymorphisms in Patients with Endometriosis in the Korean Population (한국인 자궁내막증 환자의 유전자 다형성 양상)

  • Lee, Gyeong-Hun;Choi, Young-Min
    • Journal of Genetic Medicine
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    • v.6 no.2
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    • pp.121-130
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    • 2009
  • Medical Research Center, Seoul National University College of Medicine, Seoul, Korea To analyze a wide variety of polymorphisms in patients with endometriosis is important since this disease has a strong genetic component. Until now, more than 30 Korean studies have been performed in order to elucidate the possible role of specific polymorphisms in the susceptibility to endometriosis. The most meaningful polymorphisms in Korean patients with endometriosis came from studies investigating GSTM1, AhRR, ER-alpha, VEGF, AHSG, and TNF-alpha. However, following studies should be made to confirm the consistency of the data to have some implications in the prediction of endometriosis. In this review, we also present the future direction of the association studies in complex trait disease such as endometriosis.

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Functions (Mobility, Self-care, Social Ability) and Health-related Quality of Life in Children with Cerebral Palsy

  • Ko, Joo-Yeon;Lee, Suk-Min
    • The Journal of Korean Physical Therapy
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    • v.22 no.3
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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.

Study on Validity and Reliability of Five Facet Mindfulness Questionnaire (FFMQ) for Measuring Mindfulness Meditation Program Before and After (마음챙김명상 프로그램 전후 측정도구로써 5요인마음챙김척도(FFMQ)의 신뢰성과 타당성 연구)

  • Choi, Sung-Youl
    • Journal of Oriental Neuropsychiatry
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    • v.26 no.2
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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.

Output-error state-space identification of vibrating structures using evolution strategies: a benchmark study

  • Dertimanis, Vasilis K.
    • Smart Structures and Systems
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    • v.14 no.1
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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.

Number of teeth and quality of life among the elderly: A systematic review (노인의 삶의 질과 치아 수에 관한 체계적 문헌고찰)

  • Lee, Na-Young;Choi, Hee-Na;Kim, Han-Na
    • Journal of Korean society of Dental Hygiene
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    • v.20 no.5
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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.