• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.545-546
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• 2005

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.139.2-139
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• 1999

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2019년도 춘계학술논문요약집
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• pp.86-87
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• 2019

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1318-1327
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• 2008

Geotechnical sites in urban areas may have embedded structures such as utility lines and underground concrete structures, which cause difficulties in site investigation. This study is a preliminary research to establish knowledge base for developing an optimal technique for site investigation in urban areas. Surface-wave method and resistivity survey, which are frequently adopted for non-destructive site-investigation for geotechnical sites, were investigated to characterize effects of adjacent structures. In case of surface wave method, patterns of wave propagation were investigated for typical sets of multi-layered geotechnical profiles by numerical simulation based on forward modeling theory and field experiments for small-size model tests and real-scale tests in the field. In case of resistivity survey, 3-D finite element analyses and field tests were performed to investigate effects of adjacent concrete structures. These theoretical and experimental researches for surface-wave method and resistivity survey resulted in establishing physical criteria to cause interference of adjacent structures in site investigation at urban areas.

• 한국학교ㆍ지역보건교육학회지
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• 제13권3호
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• pp.73-86
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• 2012

Objectives: This study was conducted to explore the effect of the sexuality education in elementary school in regard to students' knowledge, attitude, and role identity about sex. Methods: We classified students into experimental group and control group, and carries out the planned sexuality education to the experimental group. Study subjects were 200 students in one elementary school. Experimental group compromised of 50 boys and 50 girls, and control group so did. Self-administered questionnaire was used for preliminary investigation from 15th to 16th, October in 2009. The post investigation was carried out to the control group 5 weeks later, and to the experimental group for 5 weeks (total 10 hours, 2hours each a week) after the sexuality education from 23th of November to 25th of November, 2009. Results: Experimental group had significantly higher post-inspection scores of sex-related knowledge, attitude against sex, sex-related role identity (excluding leadership dominance, concession, cheerfulness gentleness and sympathy shyness) than pre-inspection scores. Conversely, control group had insignificantly higher post-inspection scores (excluding all scores of sex-related knowledge and scores of atttitude against sex including psychological development and pregnancy). Conclusions: Our study suggested that sexuality education in elementary school have an impact on forming knowledge, attitude, and role identity regarding the sex.

• Journal of Mechanical Science and Technology
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• 제15권4호
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• pp.522-530
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• 2001

An experimental study of compressible jet flows has been undertaken in a small transonic wind tunnel. The aim of this investigation was to realize a jet simulator in the framework of wing/nacelle integration research and to characterize the jet flow behavior. First, free jet configuration, and subsequently jet flow in co-flowing air stream configuration were analyzed. Flow conditions were those encountered in a typical flight condition of a generic transport aircraft, i.e. fully expanded sonic jet flows interacting with a compressible external flowfield. Conventional experimental techniques were used to investigate the jet flows-Schlieren visualization and two-component Laser Doppler Velocimetry (LDV). The mean and fluctuating properties were measured along the jet centerline and in the symmetric plane at various downstream locations. The results of two configurations show remarkable differences in the mean and fluctuating components and agree well with the trend observed by other investigators. Moreover, these experiments enrich the database for such flow conditions and verify the feasibility of its application in future aerodynamic research of wing/nacelle interactions.

• 대한기계학회논문집
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• 제8권5호
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• pp.416-424
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• 1984

본 연구에서는 다회로의 단상(single-phase) 자연순환계에 관한 실험 및 수치 해석적 연구로서, RWR에서의 자연순환 현상을 모사할 수 있는 fast-running code를 개 발하고 이를 실험을 통하여 입증하며, 또한 자연순환계에서 일어나는 여러 현상을 정 성적으로 관찰하는 것을 목적으로 삼았다. 이론부분은 저자의 다른 논문에 발표되었 으므로 여기에서는 요약하여 소개하며, 실험은 2-회로 PWR(고리 1호기) 1차계통을 약 1/15로 축소시킨 실험장치에서 행하였다.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.45-46
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• 2006

Experimental and numerical analysis on the heat transfer behaviors and the associated frictional loss in a rectangular channel with two inclined perforated baffles($\;5^{\circ}$) mounted on the bottom plate has been systematically performed. The parametric effects of perforated baffles (3, 6, 9 holes) and flow Reynolds number on heat transfer characteristics of the heated target surface are explored. A combination of two baffles of same overall size was considered and the flow Reynolds number for this study is varied between 28,900 and 61,800. Comparisons of the experimental data with the numerical results by commercial code CFX 5.7 are made. As for the investigation of heat transfer behaviors on local Nusselt number with the two baffles installed at $x/D_h=0.8\;and\;x/D_h=8.0$, it is evident that there exist an optimum perforation density to maximize heat transfer coefficients; i.e., the maximum Nusselt number decreases with increasing number of holes.

• Steel and Composite Structures
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• 제21권4호
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• pp.921-947
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• 2016

Concrete Filled Fibre Reinforced Polymer Tube (CFFT) for new columns construction has attracted significant research attention in recent years. The CFFT acts as a formwork for new columns and a barrier to corrosion accelerating agents. It significantly increases both the strength capacity (Strength enhancement ratio) and the ductility (Strain enhancement ratio) of reinforced concrete columns. In this study, based on predefined selection criteria, experimental investigation results of 134 circular CFFT columns under axial compression have been compiled and analysed from 599 CFFT specimens available in the literature. It has been observed that actual confinement ratio (expressed as a function of material properties of fibres, diameter of CFFT and compressive strength of concrete) has significant influence on the strength and ductility of circular CFFT columns. Design oriented models have been proposed to compute the strength and strain enhancement ratios of circular CFFT columns. The proposed strength and strain enhancement ratio models have significantly reduced Average Absolute Error (AAE), Mean Square Error (MSE), Relative Standard Error of Estimate (RSEE) and Standard Deviation (SD) as compared to other available strength and strain enhancement ratios of circular CFFT column models. The predictions of the proposed strength and strain enhancement ratio models match well with the experimental strength and strain enhancement ratios investigation results in the compiled database.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1141-1146
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• 2009

Experimental investigation on two-phase flow boiling heat transfer of R-410A and R-134a in horizontal small tubes is reported. The pressure drop and local heat transfer coefficients were obtained over heat flux range of 5 to $40\;kW/m^2$, mass flux range of 70 to $600\;kg/m^2s$, saturation temperature range of 2 to $12^{\circ}C$, and quality up to 1.0 in test section with inner tube diameters of 3.0 and 0.5 mm, and lengths of 2000 and 330 mm, respectively. The section was heated uniformly by applying a direct electric current to the tubes. The effects of mass flux, heat flux, and inner tube diameter, on pressure drop and heat transfer coefficient are presented. The experimental results are compared against several existing correlations. A new boiling heat transfer coefficient correlation based on the superposition model for refrigerants in small tubes is developed.