• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.519-524
• /
• 2003

In this report, a longitudinal adaptive flight control law is presented for the automatic landing system of a Japanese automatic landing flight experiment vehicle (ALFLEX). The longitudinal adaptive flight control law is designed to track an output of the vehicle to a guidance signal from the guidance portion of the automatic landing system. The proposed adaptive control law in the attitude control portion adjusts the controller gains continuously online as flight conditions change, in spite of the existence of unmodeled dynamics. The number of the controller gains to be adjusted is decreased to 1/2 from the previous studies. Computer simulation involving six-degree-of-freedom (DOF) nonlinear flight dynamics is performed to examine the effectiveness of the proposed adaptive control law. In order to verify the influence of the dispersion of the initial conditions, the Monte Carlo simulation is also applied. The initial conditions are more widely dispersed than the previous studies. As a result, except under the unsuitable initial conditions, the ALFLEX successfully landed on the runway.

• 아동학회지
• /
• 제36권6호
• /
• pp.147-164
• /
• 2015

The purpose of the present study was to examine the trajectories of children's negative emotionality and mother's social parenting over a 3-year period (for children at ages 1-3) and to then analyze the bidirectional effects between the two variables. The longitudinal casual relationship among children's negative emotionality, mother's social parenting and peer interaction at age 3 was also examined. The data, taken from the Panel Study on Korean Children, were analyzed using latent growth modeling. The results were as follows. First, the level of negative emotionality was seen to have increased by 2 years of age, whereas the level of mother's social parenting decreased by this point. Second, higher initial negative emotionality predicted decreases in mother's social parenting, However, higher initial mother's social parenting predicted increases in children's negative emotionality. The initial level and slope of mothers' positive parenting predicted peer interaction at age 3, while only the slope of negative emotionality predicted peer interaction. These findings suggest that temperament and parenting predict changes in each other and peer interaction.

• 아동학회지
• /
• 제25권5호
• /
• pp.1-9
• /
• 2004

본 연구의 목적은 심각한 사회병페의 한 원인으로 작용하고 있는 아동의 공격성행동이 부모빈곤과 어떻게 관련되어 있으며, 이 아동빈곤은 부모의 양육행동이 매개변인으로 작용했을 때 어느 정도까지 완충될 수 있는지를 밝히고자 하는데 있다. 종속적 연구접근으로, 부모빈곤은 아동이 생후 5개월 때, 양육행동은 17개월 때, 그리고 아동의 공격성 행동은 60개월 때 각각 측정 되었다. Structure equation modelling 분석 결과, 유아기 때의 부모빈곤은 아동기 공격성 행동을 예측하는 변인으로 작용하며, 부모의 양육행동은 그 매개체로 작용함을 입증하였다. 아울러 빈곤아동을 위한 조기 중재프로그램의 필요성을 강하게 시사하였다.

• 아동학회지
• /
• 제37권6호
• /
• pp.145-155
• /
• 2016

Objective: The purpose of this study was to investigate trajectories of child peer interaction and to compare the causal effects of their predictors, including child individual variables (i.e., gender, language ability, and cognitive ability) and teacher variables (i.e., teacher efficacy and teacher-child interaction). Methods: The participants of this study were 263 children and their teachers from the forth to sixth waves of longitudinal data from the Korean Children and Youth Panel Survey by the Korea Institute of Child Care and Education. The data was analyzed using Pearson's correlation and latent growth modeling. Results and Conclusion: The findings of this study are as follows: First, there was a linear decrease in child negative peer interaction over the course of 3 years, and significant individual differences were found in the trajectories (intercept and slope). Second, the predictors had significant casual effects on the trajectories of child negative peer interaction. The trajectories of child negative peer interaction involving girls, higher cognitive ability, and greater teacher-child interaction showed lower degree of intercept and a quicker decrease. Finally, the implications of findings are discussed.

• Journal of Oral Medicine and Pain
• /
• 제39권3호
• /
• pp.107-114
• /
• 2014

Purpose: This study want to draw conclusion based on data taken from national health insurance and determined the distribution and direction of patients treated at private clinics. Methods: The author's research spanned and compared the nationally insured patients by sexes, diagnoses, age groups and cases per year (2005, 2009, and 2013). Subjects were 3,536 patients of a private clinic in Seoul that were covered under national insurance. Results: There was no disparity across sexes nor cases, but both were on the decline. The most common dental conditions were pulpitis and dental caries at 38.4% and 16.4%, respectively. Both have decreased. Despite a drop in overall patients, the percentage of patients under 10 years old jumped substantially. Of overall age groups, teens were most prevalent at 33.5%, second and third being those in their forties and fifties (14.2% and 12.0%, respectively). Conclusions: The major illnesses that plague patients are pulpitis, dental caries, eruption disorder, gingivitis and periodontitis: the wane of pulpitis cases (a considerable percentage) and the actual numbers of patients has contributed to the general decrease in cases.

• 아동학회지
• /
• 제36권4호
• /
• pp.209-227
• /
• 2015

The present study investigated maternal parenting stress trajectories, using data gathered from the Korean Children Panel Survey. Four factors-monthly income, maternal depression levels, infants' negative emotionality, marital conflict-which were taken from reports made by the mothers' used in this study, were examined as predictors of maternal parenting stress trajectories. The effects of maternal parenting stress trajectories, parenting styles and toddlers' peer interruptive behaviors were also examined. The findings were as follows: First, maternal parenting stress trajectories somewhat increased from the 1st year period to the 4th year period. Second, infants' negative emotionality and marital conflict within the first year were observed to have a connection to the initial level and slope of maternal parenting stress trajectories. Third, maternal parenting stress trajectories predicted positive parenting styles, and parenting styles had a longitudinal impact on toddlers' peer interruptive behaviors at the 5th year period.

• 응용통계연구
• /
• 제28권2호
• /
• pp.241-250
• /
• 2015

경시적 자료 연구의 중요한 주제 중의 하나는 시간이 지남에 따라 개인의 건강 상태가 어떻게 변하는지를 추적하는 확률이다. 질병의 상태를 시간의 흐름에 따라 추적하는 것은 장기간에 걸친 임상적 관찰 연구의 계획과 분석, 그리고 질병의 예방과 치료에 중요한 의미를 지닌다. 본 논문에서는 두 다른 시점에서 각 개인의 건강 상태에 대한 조건부 확률을 추정해내는 순위 추적 확률에 대하여 연구하였다. 순위 추적 확률과 순위 추적 확률비를 추정하기 위하여 선형 혼합 효과 모형을 고려하였다. 본 논문의 방법은 아동을 대상으로 심혈관계 질환의 위험요인을 연구하는 역학 자료에 적용되었다.

• Computers and Concrete
• /
• 제25권4호
• /
• pp.369-382
• /
• 2020

This paper presents a discussion of the Finite Element Analysis (FEA) when applied for the analysis of concrete elements reinforced with glass fibre reinforced polymer (GFRP) bars. The purpose of such nonlinear FEA model development is to create a tool that can be used for numerical parametric studies which can be used to extend the existing (and limited) experiment database. The presented research focuses on the numerical analyses of concrete beams reinforced with GFRP longitudinal and shear reinforcements. FEA of concrete members reinforced with linear elastic brittle reinforcements (like GFRP) presents unique challenges when compared to the analysis of members reinforced with plastic (steel) reinforcements, which are discussed in the paper. Specifically, the behaviour and failure of GFRP reinforced members are strongly influenced by the compressive response of concrete and thus modelling of concrete behaviour is essential for proper analysis. FEA was performed using the commercial software ABAQUS. A damaged-plasticity model was utilized to simulate the concrete behaviour. The influence of tension, compression, dilatancy, mesh, and reinforcement modelling was studied to replicate experimental test data of beams previously tested at the University of Waterloo, Canada. Recommendations for the finite element modelling of beams reinforced with GFRP longitudinal and shear reinforcements are offered. The knowledge gained from this research allows for the development of a rational methodology for modelling GFRP reinforced concrete beams, which subsequently can be used for extensive parametric studies and the formation of informed recommendations to design standards.

• International Journal of Advanced Culture Technology
• /
• 제9권3호
• /
• pp.243-252
• /
• 2021

The Gwangju Daein Art Market, once declared as a declined market, was regarded as a success after an inflow of artists. However, the number of resident artists decreased from 100 at the end of 2015 to 39, to 9 in 2018, and to 6 in 2021. The project site showed signs of decline toward the completion of the project, leading to a Longitudinal study on the project's sustainability. The purpose of this study is to investigate the causes of outflow of artists and the network characteristics of the remaining artists from a sustainability perspective and thereby draw policy implications. As an analysis method, in-depth interviews and surveys were conducted. After that, we checked the remaining artists in 2018 and 2021 and identified the network characteristics. Based on the interview results, the causes of outflow were classified into programmatic, physical, and other factors. The results of a comparison showed that the levels of understanding, satisfaction, and frequency of exchange decreased. The study also provides policy implications. First, a sustainable, long-term program for the artists must involve the improvement of physical space. Second, participation in the market should be encouraged by working with artists on program composition or business progress. Third, programs for supporting exchange among artists should be further strengthened.

• 대한간호학회지
• /
• 제52권4호
• /
• pp.451-463
• /
• 2022

Purpose: This study examined the reciprocal relationships between depression and income, and gender differences in these relationships among older adults in South Korea. Methods: Using 2015 to 2019 of the Korea Welfare Panel Study (KoWePS), we studied 6,070 older adults (2,394 men and 3,676 women) aged 60 years over in 2015. The generalized estimating equation was employed to explore the effect of an individual income on depression and the reverse causal link-that of depression on income. Results: The study found the reciprocal relationships between income and depression. Income has a significant impact on depression. Higher-income was linked to decreased risks of the Center for Epidemiologic Studies Depression (CES-D) scores among older adults (B = - 0.121, p < 0.001). Estimates of the reverse causal link show that higher CES-D scores were also linked to income reduction among Korean older adults (B = - 0.007, p < 0.001). In addition, we also observed gender differences in the impact of income on depression but not in the reverse causal link. Income has more detrimental to psychological consequence for older men (B = - 0.108, p < 0.001) than older women (B = - 0.057, p < 0.001). Conclusion: The finding implies that both psychological and social protection policies for the elderly are needed in view of gender perspective.