• 대한기계학회논문집A
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• 제23권11호
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• pp.1952-1959
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• 1999

The work factor approach, so-called single specimen technique could be used to determine energy release rate from a single test record for unidirectional CLS specimen. In the present study, the work factor approach was extended to determine the mixed-mode fracture toughness of multi-directional graphite/epoxy laminated composites. Multi-directional CLS specimens were used for fracture tests. The stacking sequences used for the lap and the strap were $[90_2/0_2]_s/[0_4/90_4]_s$ and $[0/\pm45/0]_s/[0_2/\pm45_2/0_2]_2$, respectively. For both cases, the fracture toughness determined from the work factor approach was compared with that determined from the compliance method. It was found that both methods produced fracture toughness within a maximum 15% difference for each stacking sequence. The fractography analysis also showed that the fiber bridging occurred for$[0/\pm45/0]_s/[0_2/\pm45_2/0_2]_2$ case while it did not occur for $[90_2/0_2]_s/[0_4/90_4]_s$ case.

• 보건의료산업학회지
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• 제14권1호
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• pp.123-136
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• 2020

Objectives: This study aimed to analyze the factors influencing the life satisfaction of retirees(n=1,919) in one-person and multi-person households using the 2015 wave of the Korean Retirement and Income Study, collected by the National Pension Service. Methods: Frequency analysis and χ2-test were performed to examine the general characteristics and relation between one-person and multi-person household retirees. Logistic analysis was conducted to examine the factors affecting life satisfaction. Results: Public pension income was a statistically significant factor affecting life satisfaction, economic, health, and life in multi-person households. Conclusions: To improve life satisfaction after retirement, selective insurance benefits are needed depending on the type of household. Moreover a policy for expanding labor market participation is needed.

• 대한전기학회논문지
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• 제37권5호
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• pp.282-288
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• 1988

A Multi-grid method is introduced to Finite Element Analysis of electromagnetic field problems in order to reduce the computational time. The puropse of this work is to study how to intermix discretization and solving process, thereby making the process more effective and to find the optimal factors of Multi-grid method. Several numerical experiments with linear models of uniform and nonuniform grids confirm that the proposed algorithm can reduce the computational time very effectively as compared with con ventional iterative methods. The best results are obtained with V cycle and S.O.R. with the acce leration factor of 1.3-1.4 for smoothing.

• 한국환경과학회지
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• 제15권9호
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• pp.887-895
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• 2006

Through this research of the analysis on the frequency flood discharges regarding basin property factors, a linear regression system was introduced, and as a result, the item with the highest correlation with the frequency flood discharges from Nakdong river basin is the basin area, and the second highest is the average width of basin and the river length. The following results were obtained after looking at the multi correlation between the flood discharge and the collected basin property factors using the data from the established river maintenance master plan of the one hundred twenty-five rivers in the Nakdong river basin. The result of analysis on multivariate correlation between the flood discharges and the most basic data in determining the flood discharges as basin area, river length, basin slope, river slope, average width of basin, shape factor and probability precipitation showed more than 0.9 of correlation in terms of the multi correlation coefficient and more than 0.85 for the determination coefficient. The model which induced a regression system through multi correlation analysis using basin property factors is concluded to be a good reference in estimating the design flood discharge of unmeasured basin.

• 대한기계학회논문집
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• 제14권5호
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• pp.1079-1086
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• 1990

본 연구에서는 모아레 경사격자법(moire tilted master grating method)을 개 발하여 그 유용성을 확인하고 이를 굴절 및 편심균열의 응력확대계수의 해석에 확대 적용하여 다점선정법의 적용범위를 넓히고, 또 분포균열 및 임의 형균열의 해석 가능 성을 타진하여 완성된 실험법으로서의 위치를 구축하는데 목적이 있다.

• 아동학회지
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• 제33권6호
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• pp.85-107
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• 2012

In this study, the Infants & Toddlers' Playfulness Scale(ITPS) was developed and its reliability and validity were examined. The participants in this study consisted of 656 parents whose children were 8 to 36 months old. Five factors were identified from the results of the exploratory factor analysis performed on the 29 items that had been derived by analyzing existing research. The Goodness of Fit Indices(GFIs) of the confirmatory factor analyses, performed on the 1st-order 5-factor model and the 2nd-order one factor model, were both satisfactory. Concurrent validity was established by the high correlations of r = .631~.808(p < .01) between each factor of the ITPS and the total score of the Children's Playfulness Scale(CPS), an existing measure for children's playfulness. The reliability of each factor, as measured by Cronbach's ${\alpha}$, ranged from .773 to .883. Consequently, the ITPS developed in this study can be seen as a reliable and valid scale that can be used by parents to measure the playfulness of their infants and toddlers in a multi-dimensional manner.

• 한국사회복지학
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• 제63권2호
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• pp.319-336
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• 2011

본 연구는 외국인 며느리를 둔 시부모를 대상으로 하여 문화적응 스트레스를 측정하기 위한 척도를 개발하고 그 신뢰도와 타당도를 검증해보고자 하였다. 이를 위하여 기존의 유학생을 대상으로 하는 문화적응 스트레스 척도를 기본척도로 하여 다문화 가정의 시부모에 적합하도록 재구성하였다. 분석 결과, 문항의 제거와 표본의 이상치 점검을 위한 문항분석을 통하여 최종적으로 11문항이 선정되었다. 다음으로 문화적응 스트레스 척도의 요인구성을 살펴보기 위하여 탐색적 요인분석을 실시하였으며 시부모의 문화적응 스트레스 척도는 '편견 및 차별감 지각', '문화적 가치관 차이로 인한 갈등', '일상생활의 불편'의 세 가지 요인으로 구성됨을 확인하였다. 이렇게 구성된 척도의 타당도를 검증하기 위하여 구조모형을 통한 확인적 요인분석을 실시하였으며 그 결과 양호한 모형적합도를 보여주었다. 척도의 신뢰도는 Cronbach's ${\alpha}$로 검증하였으며 0.86으로 나타났다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.205-210
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• 2007

The existing capacity spectrum method (CSM) is based on the displacement based approach for seismic performance and evaluation. Currently, in the domestic and overseas standard concerning seismic design, the CSM to obtain capacity spectrum from capacity curve and demand spectrum from elastic response spectrum is presented. In the multistory building, collapse is affected more by drift than by displacement, but the existing CSM does not work for story drift. Therefore, this paper proposes an improved CSM to estimate story drift of structures through seismic performance and evaluation. It uses the ductility factor in the A-T domain to obtain constant-ductility response spectrum from earthquake response of inelastic system using the drift and capacity curve from capacity analysis of structure.

• 소성∙가공
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• 제17권8호
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• pp.627-632
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• 2008

The cross sectional shape of intermediate die is one of important parameters to improve dimensional accuracy of final product in shaped drawing process. Until now, it has been designed by the experience or trial and error of the expert. In this study, the cross sectional shape of intermediate die for spline shape is determined by the electric fields analysis and scale factor method. The result of the electric fields analysis and scale factor method have been compared with that of the expert method. The effects of cross sectional shape on the dimensional accuracy were investigated by using FE-simulation. And then the multi-stage shaped drawing experiments were performed to verify the results of FE-simulation. As a result, the cross sectional shape from the electric fields analysis and scale factor method had the good dimensional accuracy. These two methods can be used for the method to obtain the cross sectional shape of intermediate die in shaped drawing process.

• 한국통신학회논문지
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• 제30권9A호
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• pp.795-802
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• 2005

바이너리 CDMA(B-CDMA) 기술은 CDMA 신호의 크기를 일정하게 유지시키는 새로운 변조 기법이다. 다중코드CDMA 신호를 일정한 레벨의 신호로 양자화한 후 변조함으로써 B-CDMA 기술은 CDMA 신호가 가지는 장점들을 유지하는 동시에 최대전력 대 평균전력의 비율을 감소시킨다. 본 논문에서는 확산인자가 현저히 작지 않은 가정 하에 B-CDMA시스템의 성능을 다중 경로 페이딩 환경에서 분석한다. 수학적 분석 결과는 컴퓨터 모의실험을 통하여 검증된다.