• 한국농공학회지
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• 제30권4호
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• pp.45-61
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• 1988

The purpose of this study is to develop regression equations between annual specific sedi- ment of reservoirs and physiographic factors of watersheds. 122 irrigation reservoirs, which have irrigation areas equal to or larger than 200 ha, located in Korea except Cheju province are used in the analysis. Simple regression analyses between the specific annual sediment and each of the physical characteristic factors of the reservoirs are carried out at first. Then, multiple regression analyses between the annual specific sediment and the physical characteristic factors with high correlation coefficients in the simple regression analyses are made. The results obtained from this study are as follows : 1. The results of the sirnple regression analyses show that in each province the watershed area, the length of mainstream, the circumferential length of watershed have high cor- relation coefficients (R=0.814-0.986), and that drainage density, reservoir capacity per watershed area, drainage frequency, basin relief have low correlation coefficients (R=0. 387-0.955). 2. The purposed multiple regression equations between the annual specific sediment of reservoirs and three major characteritic factors of watersheds, namely, the watershed area, the circumferential length of watershed, and the length of mainstream, are proposed as given in Table 2. 3. The result of the simple regression analyses with respect to the reservoir elevation except Jeonnam province, which has very different characteristics comparing to other provinces, shows that watershed area, main stream length and circumferential length have high correlation coefficients (R=0.806-0.884) in low-elevation reservoirs and intermediate- elevation reservoirs, but low correlation coefficients (R=0.639-0.739) in high-elevation reservoirs. 4. With respect to the reservoir elevation, the proposed multiple regression equations bet- ween the annual specific sediment of reservoirs and the three major characteristic factors of watershed which have high correlation coefficients are proposed as given in Table 5.

• Asian-Australasian Journal of Animal Sciences
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• 제29권7호
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• pp.938-943
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• 2016

Development of body hair is an important physiological and cellular process that leads to better adaption in tropical environments for dairy cattle. Various studies suggested a major gene and, more recently, associated genes for hairy locus in dairy cattle. Main aim of this study was to i) employ a variant of the discordant sib pair model, in which half sibs from the same sires are randomly sampled using their affection statues, ii) use various single marker regression approaches, and iii) use whole genome regression approaches to dissect genetic architecture of the hairy gene in the cattle. Whole and single genome regression approaches detected strong genomic signals from Chromosome 23. Although there is a major gene effect on hairy phenotype sourced from chromosome 23: whole genome regression approach also suggested polygenic component related with other parts of the genome. Such a result could not be obtained by any of the single marker approaches.

• 한국국방경영분석학회지
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• 제34권1호
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• pp.47-59
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• 2008

본 연구는 방위산업체의 연구개발 투자활동이 경영성과에 대하여 어떠한 영향을 미치는지에 대하여 실증적 분석을 수행하였다. 연구의 주요 분석 결과에 대해서 살펴보면 다음과 같다. 첫째, 방위산업체의 성장성 증대를 위해서는 연구인력의 교육지원 기회 확대, 관련부서간의 긴밀한 협력이 필요한 것으로 나타났다. 둘째, 방위산업체의 생산성 증대를 위해서는 연구개발 투자비를 증대해야 하며, 셋째, 방위산업체의 수익성 증대를 위해서는 관련부서 간 협력강화가 정(+)의 영향을 미치는 것으로 나타났다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.980-987
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• 2006

Recently, twin-tunnel is often designed considering the aspects of disaster prevention and economic reasons. However, the design cases and the studies are relatively insufficient. By the twin-tunnel excavation, deviate stresses of pillar between tunnels are increased and the increased stresses induce the instability of the twin-tunnel. In this study, numerical analyses about the twin-tunnel behaviour are conducted while varying ground strength, width of pillar and depth of earth cover and a series of regression analyses are carried out by using the results of numerical analyses for the twin-tunnel. Based on the numerical analyses, an estimation method of derived stresses is suggested though the regression analyses. Also, based on the results of regression analyses, an quantitative estimation method considering the reinforcement effects is also suggested. Then various parametric studies are conducted to be considered the reinforcement type and various design parameters. Finally, the efficiency of the suggested method is verified through the results of parametric studies.

• Environmental Engineering Research
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• 제15권3호
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• pp.135-140
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• 2010

With the various urban characteristics of each city, the existing water demand prediction, which uses average liter per capita day, cannot be used to achieve an accurate prediction as it fails to consider several variables. Thus, this study considered social and industrial factors of 164 local cities, in addition to population and other directly influential factors, and used main substance and cluster analyses to develop a more efficient water demand prediction model that considers unique localities of each city. After clustering, a multiple regression model was developed that proved that the $R^2$ value of the inclusive multiple regression model was 0.59; whereas, those of Clusters A and B were 0.62 and 0.74, respectively. Thus, the multiple regression model was considered more reasonable and valid than the inclusive multiple regression model. In summary, the water demand prediction model using principal component and cluster analyses as the standards to classify localities has a better modification coefficient than that of the inclusive multiple regression model, which does not consider localities.

• 벤처창업연구
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• 제6권4호
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• pp.1-20
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• 2011

본 연구는 창업 여성CEO들을 대상으로 여성CEO의 특성과 경영성과 사이에는 어떤 상관성이 있는지에 대하여 살펴보고자 하였다. 이를 위하여 창업 여성CEO의 특성과 역량을 중심으로 하여 선행연구와 기존 문헌을 토대로 여성CEO의 특성요인으로서 경력 특성, 행위적 특성, 역량 특성 등 결정요인을 도출하고 이들 요인과 경영성과와의 관계에 대한 연구모형 과 가설을 설정하고 이를 실증적으로 분석, 검증하는데 연구의 목적을 두었다. 본 연구의 실증분석 결과는 다음과 같다. 첫째, 창업 여성CEO의 경력 특성과 경영성과간의 관계를 검증한 회귀분석 결과에서는 전공 요인은 유의미한 영향을 미치지만 직장 또는 창업경험 요인은 유의하지 않은 것으로 나타났다. 둘째, 창업 여성CEO의 행위적 특성과 경영성과 사이에서는 창업동기 요인은 유의미한 영향을 미치지만 실패 가능성이나 위험에 대한 대처 노력 요인은 유의하지 않은 것으로 나타났다. 셋째, 창업 여성CEO의 역량 특성과 경영성과에서는 관리적 역량 요인은 유의미한 영향을 미치지만 기업가적 역량 요인과 기술적 역량 요인은 유의하지 않은 것으로 나타났다.

• Geomechanics and Engineering
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• 제17권1호
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• pp.11-18
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• 2019

The formulas offered so far on the settlement of raft footings provide only a rough estimate of the actual settlement. One of the best ways to make an accurate estimation is to conduct 3-dimensional finite element analyses. However, the required procedure for these analyses is comparatively cumbersome and expensive and needs a bit more expertise. In order to address this issue, in this study, a raft footing settlement formula was developed based on ninety finite element model configurations. The formula was derived using multi-parameter exponential regression analyses. The settlement formula incorporates the dimensions and the elastic modulus of a rectangular raft, vertical uniform pressure and soil moduli and Poisson's ratios up to 5 layers. In addition to this, an equation was offered for the estimation of average deflection of the raft. The proposed formula was checked against 3 well-documented case studies. The formula that is derived from 3D finite element analyses is useful in optimising the raft properties.

• 한국환경과학회지
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• 제23권3호
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• pp.387-397
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• 2014

This study is carried out to propose an empirical equation which can promptly predict the aircraft noise level at a specific point (a receptor) near Jeju international airport by using the information of the flight path data. For this purpose, Analyses of multiple linear regression with the slant distances (SD) calculated from the gate analyses of the flight path data, aircraft noise certification levels with unit of EPNL(effective perceived noise level) and noise levels measured at receptors are performed by SPSS package. From these regression analyses for approach and departure of aircraft, we can propose empirical equations which is statistically significant. The noise levels predicted by these empirical equations are highly correlated the measured data.

• Advances in Computational Design
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• 제3권1호
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• pp.87-112
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• 2018

In this study, it is aimed to present engineering software to estimate the structural response of concrete arch dam. Type-1 concrete arch dam constructed in the laboratory is selected as a reference model. Finite element analyses and experimental measurements are conducted to show the accuracy of initial model. Dynamic analyses are carried out by spectrum analysis under empty reservoir case considering soil-structure interaction and fixed foundation condition. The displacements, principal stresses and strains are presented as an analysis results at all nodal points on downstream and upstream faces of dam body. It is seen from the analyses that there is not any specific ratio between prototype and scaled models for each nodal point with different scale values. So, dynamic analyses results cannot be generalized with a single formula. To eliminate this complexity, the regression analysis, which is a statistical method to obtain the real model results according to the prototype model by using fitting curves, is used. The regression analysis results are validated by numerical solutions using ANSYS software and the error percentages are examined. It is seen that 10% error rates are not exceeded.

• 한국의류산업학회지
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• 제12권4호
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• pp.450-458
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• 2010

The purpose of this study was to investigate the effect of shopping orientation on price perception and the effect of shopping orientation and price perception on purchase satisfaction. This study administered a questionnaire survey to adults in their 20s and 30s who had once purchased fashion products in surrogate internet shopping malls. Among 327 questionnaires, 263 were collected through convenience sampling and 94 were collected from six internet communities. Data were analyzed by factor analyses and regression analyses. The results of this study are as follows. First, factor analysis of price perception revealed that two factors such as price reasonability and price reduction were extracted and the mean of price reduction was higher than one of price reasonability. Second, factor analysis of purchase satisfaction extracted four factors such as service quality, shopping convenience, product scarcity and product variety/price satisfaction. Mean comparisons showed that the mean of product scarcity was the highest among four factors. Third, regression analyses that recreational, economic, and convenience shopping orientation affected price reduction, a factor of price perception. Fourth, regression analyses showed that shopping orientations and the price perception had significant effects on the purchase satisfaction.