• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.1
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• pp.78-82
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• 2002

In this paper, we have studied a numerical stability analysis method for the robust fuzzy feedback linearization regulator using Takagi-Sugeno fuzzy model. To analyze the robust stability, we assume that uncertainty is included in the model structure with known bounds. For these structured uncertainty, the robust stability of the closed system is analyzed by applying Linear Matrix Inequalities theory following a transformation of the closed loop systems into Lur'e systems.

• The KSFM Journal of Fluid Machinery
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• v.13 no.3
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• pp.5-11
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• 2010

As a basic study of the aero-acoustic noise, Large eddy simulations were carried out for a fixed circular cylinder at Renolds number (Re=$9.0\times10^4$) using commercial CFD code, FLUENT. The subgrid-scale turbulent viscosity was modeled by Smagorinsky-Lilly model adapted to structured meshes. The results of analysis showed that time-averaged value, $\bar{C}_D$ is approximately 1.47 which is considerably adjacent with the experimentally measured value of 1.32 in comparison to the values performed by previous researchers. It is observed that there are the very small acoustic pressure fluctuation with the same frequency of the Karman vortex street.

• Journal of The Korean Association For Science Education
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• v.23 no.4
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• pp.430-441
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• 2003

The purpose of this study was to investigate the effects of students' prior knowledge on scientific reasoning in solving a pendulum task with a computer simulation. Subjects were 60 Korean students: 27 fifth-grade students from an elementary school and 33 seventh grade students from a middle school located in a city with 300,000 people. This study adapted a pendulum task presented with a computer simulation on which subjects would use a pattern of multivariable causal inferences. The subjects were interviewed individually in a three-phase structured interview by the researcher and three assistants while he/she was investigating the pendulum task. This study showed that most students across grades focused heavily on demonstrating the primacy of their prior knowledge or their current hypothesis. In addition, students' theories that are part of one's prior knowledge have a significant impact on formulating, testing, and revising hypotheses. Therefore, this study supported the notion that students' prior knowledge had a strong effect on students' experimental intent and hypothesis evaluation.

• Child Health Nursing Research
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• v.22 no.2
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• pp.71-78
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• 2016

Purpose: The purpose of this study was to investigate the influence of child-care efficacy, job efficacy, and health promoting lifestyle on the job satisfaction of in-home child care helpers who are called Idolbomi. Methods: Participants for this survey were 153 in-home child care helpers who worked in Seoul. Data were collected from May 23 to October 17, 2014 using self-report structured questionnaires. Data were analyzed using IBM/SPSS 18.0 program. Results: There were significantly positive correlations between child-care efficacy, job efficacy, health promoting lifestyle, and job satisfaction. Stepwise multiple regression analysis revealed that the predictors of job satisfaction were spiritual growth, education level, job efficacy, effect of income. Conclusion: Therefore, we need to develop strategies to enhance the job efficacy and health promoting lifestyle of in-home child care helpers to improve their job satisfaction.

• Child Health Nursing Research
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• v.22 no.4
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• pp.309-316
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• 2016

Purpose: This study of secondary analysis aims to compare family management style according to severity in children with atopic dermatitis. Methods: A convenience sample of 109 Korean mothers caring for a child with atopic dermatitis, were recruited from the pediatric departments of two general hospitals in Seoul. Data were collected from November 1, 2015 to February 28, 2016. A structured self-report questionnaire was used. Data were analyzed using descriptive statistics, correlation analysis, and one-way ANOVA with IBM SPSS Version 22.0. Results: For family management style, condition management effort, family life difficulty, and view of condition impact were significantly different according to the severity of the atopic dermatitis in these children. Conclusion: The findings indicate that family management strategies to enhance care of children with atopic dermatitis as well as members of the family should include these significant variables in a family-centered approach.

• Korean Journal of Occupational Health Nursing
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• v.26 no.2
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• pp.105-113
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• 2017

Purpose: The purpose of this study was to identify the impact of workplace bullying experience and resilience on organizational commitment in general hospital nurses. Methods: Participants were 250 nurses of a general hospital in Seoul, Gyeonggi-do and Gangwoen-do. Data were collected using the structured questionnaires and analyzed using descriptive statistics, t-test, ANOVA, pearson's correlation coefficient, and multiple regression analysis. Results: As a result of multiple regression analysis, workplace bullying, resilience, clinical career, and work unit turned out to be variables that explained general hospital nurses' organizational commitment (Adj. $R^2=0.17$, p<.001). Conclusion: These findings suggest that bullying and resilience were defined as the influential variables on organizational commitment of nurses. Therefore strategies and programs about workplace bullying and resilience are needed to be developed.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.26.6-26
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• 2001

In this paper we introduce a new algorithm that enables radial basis function network(RBFN) to be structured automatically and guarantees the stability of the RBFN. Because this new algorithm is efficient and also have the advantage of fast computational speed we adopt this algorithm as online learning scheme for uncertain nonlinear dynamical systems. Based on the fact that a 3-layered RBFN can represent a specific nonlinear function reasonably well by linearly combining a set of nonlinear and localized basis functions, we show that this RBFN can identify the nonlinear system very well without knowing the information of the system in advance.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.1006-1013
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• 1988

We have shown how unstructured modeling was used to derive a general stability condition in Part 1. In Part 2, we focus on the particular dynamics (structures modeling) of the robot manipulator and environment. Using rigid body dynamics, the stability condition for the direct drive robots has been achieved in terms of the Jacobian and robot tracking controller. Combining the structured and unstructured modeling, a stability condition for a particular application can be obtained. This approach has been used to analyze compliant motion on the University of Minnesota robot using a feedforward torque controller. We have obtained a stability condition for this application. Through both simulation and experiment, the sufficiency of this condition has been demonstrated. For a sufficient stability condition, recall that if the condition is satisfied, then the stability is guaranteed; however, if the condition is violated, no conclusion can be made.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.425-428
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• 2003

Recently, the IDS(Intrusion Detection System) using a video camera is an important part of the home security systems which start gaining popularity. However, the video intruder detection has not been widely used in the home surveillance systems due to its unreliable performance in the environment with abrupt illumination change. In this paper, we propose an effective moving edge extraction algorithm from a sequence image. The proposed algorithm extracts edge segments from current image and eliminates the background edge segments by matching them with reference edge list, which is updated at every frame, to find the moving edge segments. The test results show that it can detect the contour of moving object in the noisy environment with abrupt illumination change.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.839-842
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• 2003

본 논문에서는 MPEG-4 디블록킹 필터를 매크로블록 단위의 효율적인 파이프라인 구조를 사용하여 구현하였다. MPEG-4 QCIF/CIF 영상 시퀀스의 디블록킹 필터링 효과를 보일것이며, 디블록킹 필터링의 많은 계산량을 줄임과 동시에 낮은 클록에서 실시간 처리할 수 있는 구조를 제안하였다. 대부분 블록기반의 비디오 코딩 시스템에서, 블록 에지 효과는 블록기반 영상 압축에 치명적인 화질 저하를 나타낸다. 특히 압축 비율이 커질수록 화질 저하는 뚜렷하다. 그래서, 영상 후처리 기술로서 디블록킹 필터를 사용하여 블록 에지 영향을 줄임으로써 영상 화질을 향상시킨다. 그러나 디블록킹 필터의 주요 단점은 많은 계산량을 요구하고 있어서 구현에 어려움이 있다. 이 문제를 해결하기 위해, MPEG-4 디블록킹 필터를 매크로 블록단위의 파이프라인 구조로 설계하였고, 실시간으로 동작하는 MPEG-4 SP@L2의 비디오 코덱 칩을 구현하였다.