• Imaging Science in Dentistry
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• 제41권4호
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• pp.155-159
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• 2011

Purpose : This study was performed to determine the prevalence of maxillary canine impaction on a basis of a single panoramic radiograph in Bangladeshi population. Materials and Methods : A random sample of seven hundred panoramic radiographs was collected from the patient record of a dental clinic. All the selected panoramic radiographs were taken from January 2009 to August 2010 by a single panoramic radiograph machine with the same exposure time (19 seconds) for all radiographs. One hundred and twenty panoramic radiographs were excluded to minimize the selection bias. In a dim lit room, an observer assessed the radiographs on a standard radiographic light box. The position of the impacted maxillary canine was recorded in line with the longitudinal axis of a tooth using the edge of a metal ruler. Data were subsequently put on SPSS 11.5 software and chi-square (${\chi}^2$) tests were applied to find out the association. Results : Among 580 panoramic radiographs it was found that impacted maxillary canines were present in only 7 (1.2%) radiographs. A statistical significant difference was found between the age of the patients and the vertical position of the impacted canines (p=0.000) and between the age of the patients and the horizontal position of the impacted canines (p=0.003). Conclusion : The prevalence was found to be low compared with the present study from the limitation of panoramic image. Further study needs to include three-dimensional imaging modality.

• 한국통신학회논문지
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• 제37권7C호
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• pp.544-553
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• 2012

자동차 측위 기술은 충돌 경고, 적응형 주행 제어 등의 다양한 지능형 자동차 서비스들을 제공하는데 있어 필수적인 기술이다. 본 논문에서는 자동차에 장착된 레이더 등의 센서로부터 수신하는 주변 자동차들의 상대적 위치 정보와 자동차 간 통신을 통해 수신하는 주변 자동차들의 GPS 측위값을 융합하여 자기 자동차의 측위 정확도를 향상하는 융합 측위 알고리듬을 제시한다. 제안하는 알고리듬은 탐욕적 측위 데이터 매핑 알고리듬과 융합 측위보정 알고리듬으로 구성된다. 전자는 거리를 기반으로 GPS 측위값과 센싱 측위값을 대응시키고, 후자는 대수 법칙에 기반하여 자기 자동차의 GPS 측위값을 보정한다. 시뮬레이션을 통해 융합 측위 알고리듬의 RMS 측위 정확도가 기존의 GPS 기반 RMS 측위 정확도에 비해 종방향으로 30 % 이상, 횡방향으로 60 % 이상 향상할 수 있음을 보였다.

• 한국인구학
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• 제34권2호
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• pp.135-162
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• 2011

청소년 자살률이 점차 증가하고 있는 가운데, 한국청소년패널데이터(KYPS)를 활용하여 청소년이 인식하는 부모, 친구, 교사, 지역사회와의 관계와 자살충동간 인과관계를 확인하고 이에 대한 성별차이를 분석하였다. 두 가지 중요한 발견은 다음과 같다: 첫째, 전년도(t-1) 부모지지, 친구지지, 교사지지, 지역사회지지, 자살충동의 수준이 높을수록 다음 해(t)의 같은 요인의 수준이 모두 높았다. 둘째, 각 지지 요인과 자살충동간 교차경로에서 유의한 성별차이가 발견된 모형은 부모지지와 친구지지 모형이었다. 두 모형 모두 중학교 3학년의 부모(친구)지지의 수준이 높을수록 고등학교 1학년의 자살충동이 낮아짐을 발견하였다. 본 연구를 통해 자살충동의 내적역동이 시간의 흐름에도 불구하고 일관성을 지니므로 주변인과의 관계, 지지 등과 같은 개인 외적 요인의 긍정적 효과에 주목해야 할 필요성과 함께 약한 인과관계를 보였던 교사, 지역사회 지지를 강화시켜 청소년의 자살충동을 감소시킬 수 있는 방법을 강구해야 할 것을 제언하였다.

• 동아시아식생활학회지
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• 제15권4호
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• pp.397-404
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• 2005

The propose of this study was to investigate taurine intake in formula-fed and breast-fed infants and to estimate the level of taurine of blood and urine in order to determine the requirement of taurine intake in infants. These results will be useful to suggest the guideline of requirement of taurine intake and may contribute toward the proper use of breast milk substitutes. Experimental groups were breast-fed infants (n=10) and formula-fed infants (n=10) of 20 normal delivery infants in general hospital. This study was longitudinal study from birth up to 16weeks (0 week, 4 weeks, 8 weeks, 12 weeks, 16 weeks). The items of test were anthropometry(weight, height, head circumference, chest circumference), intake of taurine, taurine level of blood and urine in breast-fed and formula-fed infants. There were no significant differences between breast-fed and formula-fed infants in weight, height, head and chest circumference. There is a need for future studies of exclusive infants with larger samples to determine which growth pattern should be considered as the norm. Taurine concentration of plasma and urine did not differ between breast-fed and formula-fed infants. Taurine intake recommendations for infants is about 30mg/day from this study. This data will be useful for production of human-like formula milk and suggestion of an index of selection of a consumer in taurine.

• 한국생활과학회지
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• 제19권6호
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• pp.1031-1044
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• 2010

Corresponding to the rapid growth of the aging population without an adequate social safety net for the elderly, older people face great disadvantages due to sudden illness or poor health and a lack of support from the younger generation. Furthermore, older women are suffering from a drastic deterioration of their economic status because of insufficient retirement savings. Examining the impact of labor force participation and living arrangement on health status and life satisfaction in later life, it is important to consider gender differences in context of social policies for the elderly. Using data based on a stratified national sample of the elderly by the Korean Longitudinal Study of Aging (KLoSA), multiple regression model were used to estimate the relationships between labor force participation and health status and subjective life satisfaction concerning the quality of their later life. The result indicates that good health status and high level of life satisfaction are associated with the type of paid work status for the elderly men, but those are associated with the type of non paid work, such as family businesses employees for the elderly women. Significant differences in chronic health condition and subjective life satisfaction by employment characteristics are found among the elderly. In addition, older women's high level of life satisfaction was associated with the participation of the social activity. The major conclusion from these results should help us understand gender differences in the elderly and acknowledge further exploration of gender variations in these people's later life.

• 대한조선학회논문집
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• 제57권4호
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• pp.182-190
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• 2020

This study reports a series of drop impact tests performed to generate denting damages on stiffened plates and their residual ultimate strength tests under axial compression. The models were fabricated of general structural steel, and each model has six longitudinal stiffeners and two transverse frames. Among six fabricated models, four were damaged, and two were left intact for reference. To investigate the effects of collision velocity and impact location on the extent of damage, the drop height and the impact location were changed in each impact test. After performing the collision tests, the ultimate axial compression tests were conducted to investigate the residual strengths of the damaged stiffened plates. Finite element analyses were also carried out using a commercial package Abaqus/Explicit. The material properties obtained from a quasi-static tensile tests were used, and the strain-rate sensitivity was considered. After importing the collision simulation results, the ultimate strength calculations were carried out and their results were compared with the test data for the validation of the finite element analysis method.

• 한국물환경학회지
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• 제24권1호
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• pp.54-62
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• 2008

It is often believed that a more complex water quality model is better able to simulate reality. The more complex a model, however, the more parameters are involved thus increases the cost and uncertainty of modeling processes. The objective of this study was to compare the performance of two steady-state river water quality models, QUAL2E and QUAL-NIER, that have different complexity. QUAL-NIER is recently developed by National Institute of Environmental Research aiming to enhance the simulation capability of QUAL2E for eutrophic rivers. It is a carbon based model that considers different forms, such as dissolved versus particulate and labile versus refractory, of carbon and nutrients, and the contribution of autochthonous loading due to algal metabolism. The models were simultaneously applied to Nakdong River and their performance was evaluated by statistical verification with field data. Both models showed similar performance and satisfactorily replicated the longitudinal variations of BOD, T-N, T-P, Chl.a concentrations along the river. The algal blooms occurred at the stagnant reaches of downstream were also reasonably captured by the models. Although QUAL-NIER somewhat reduced the magnitude of errors, the hypothesis tests revealed no statistical evidence to justify its better performance. The contribution of autochthonous carbon and nutrient load by algal metabolism was insignificant because the hydraulic retention time is relatively short compare to the time scale of kinetic reactions. The results imply that the kinetic processes included in QUAL-NIER are too complex for the nature and scale of the real processes involved, thus needs to be optimized for improving the modeling efficiency.

• 가족자원경영과 정책
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• 제14권2호
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• pp.109-126
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• 2010

This study set out to investigate if work-family conflict and work-family enhancement would have mediating effects on the impact of gender role attitudes of women from double income households on their satisfaction of work and marriage. A structural modelof gender role attitudes was set as the independent variable, work-family conflict and work-family enhancement as the mediating variables, and work satisfaction and marriage satisfaction as the dependent variables. The subjects consisted of 2,713 married women from double income households and information was obtained from the first year data of the Korean Longitudinal Survey of Women and Families (KLoWF) collected by the Korean Women's Development Institute (KWDI). Using SPSS 15.0 software, descriptive statistics were gathered, and frequency and factor analyses were conducted. AMOS 7.0 software was used to analyze both the measurement model and the structural model. The results indicate that work-family conflict and work-family enhancement had partial mediating effects on the impacts of gender role attitudes on work and marriage satisfaction among women from double income households. Notably, work-family enhancement had a greater effect than work-family conflict, which suggests that the elements of work-family enhancement, which are the positive aspects of work on family and family on work, should be promoted. It is, however, also important to make efforts to resolve work-family conflict by increasing the satisfaction level of work and marriage among women from double income households.

• 한국콘텐츠학회논문지
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• 제13권4호
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• pp.218-229
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• 2013

한국의 고령화로 증가한 노인인구가 행복한 노년의 삶을 사는데 필요한 요소 중의 하나로 사회활동의 참여가 있다. 다양한 사회활동의 하나 중 자원봉사활동은 사회적으로는 시민사회의 기반이 되는 역할을 하며 개인적으로 노인의 삶의 질을 향상시키는 효과가 있다. 본 연구는 한국 노인의 자원봉사활동 현황과 자원봉사활동 참여 요인을 분석하되 노인인구의 다양성을 고려하여 연령집단별로 분석하는 것을 목적으로 한다. 한국 고령화 연구 패널의 2차년도 자료에서 55세 이상의 노인을 예비노인(55세-65세), 전기노인(65세-74세), 후기노인(75세 이상)으로 분류하여 기술통계와 로지스틱 회귀분석으로 분석하였다. 분석 결과, 노인의 자원봉사활동 참여율은 매우 낮았으며, 노인의 사회적 관계가 노인이 자원봉사활동 참여에 중요한 역할을 하는 것으로 밝혀졌다. 또한 연령별 다양성을 고려해야 할 필요성도 확인되었다.

• 한국콘텐츠학회논문지
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• 제13권7호
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• pp.452-462
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• 2013

이 연구는 학교문화, 구체적으로는 교사의 협력문화, 학교장의 지도성, 학생의 교우관계가 학생, 학부모, 교사, 학교장 등 학교구성원의 학교만족도에 미치는 영향을 탐색적으로 살펴보았다. 이를 위하여 2011년에 조사된 서울교육종단연구의 설문자료를 활용하여 기술통계 분석, 상관관계 분석, 다중회귀분석 등을 실시하였다. 연구 결과, 학생과 학부모의 학교만족도에는 학생의 교우관계와 교사의 협력문화가, 교사의 학교만족도에는 학교장의 지도성과 교사의 협력문화가 통계적으로 유의한 영향을 미치는 것으로 나타났다. 이 연구는 학교 단위에서 교사의 협력문화가 학생, 학부모, 교사의 학교만족도에 공통적으로 영향을 미치는 요인임이 밝혀졌고, 각각 연구되는 경향이 강했던 학생과 학부모, 교사와 학교장의 학교만족도와 학교문화를 제한적으로나마 동시에 살펴보았다는 점에서 의의가 있다.