• 한국수학교육학회지시리즈D:수학교육연구
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• 제13권1호
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• pp.31-48
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• 2009

Utilizing the path analysis method, the study explores the relationships among the influential factors in mathematics modeling academic achievement. The following conclusions are drawn: 1. Achievement motivation, creative inclination, cognitive style, the mathematical cognitive structure and mathematics modeling self-monitoring ability, those have significant correlation with mathematics modeling academic achievement; 2. Mathematical cognitive structure and mathematics modeling self-monitoring ability have significant and regressive effect on mathematics modeling academic achievement, and two factors can explain 55.8% variations of mathematics modeling academic achievement; 3. Achievement motivation, creative inclination, cognitive style, mathematical cognitive structure have significant and regressive effect on mathematics modeling self-monitoring ability, and four factors can explain 70.1% variations of mathematics modeling self-monitoring ability; 4. Achievement motivation, creative inclination, and cognitive style have significant and regressive effect on mathematical cognitive structure, and three factors can explain 40.9% variations of mathematical cognitive structure.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2233-2238
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• 2003

It is well known that organized vortex rotations swirl and tumble greatly affect the mixing, the combustion and heat transfer processes in engine cylinder. We have developed 3 dimensional numerical simulation codes whose predictions make good agreement with the experimental data. Large eddy simulation based on Smagorinsky subgrid scale model was adopted to describe the turbulence of in-cylinder flows. The tumble motions generated by different inclination angles between valve-port and cylinder head have been calculated. The results show that the angles between direction of induced flow and cylinder walls which the flow collides with play a great role in the formation and generation of tumble motions. Therefore, it is inferred that seat angle and inclination angle are important factors of engine design. In addition, the numerical results of different engine speed -1000 rpm and 3000 rpm are very similar in the flow structure.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.48-53
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• 2001

This experimental study is to research heat transfer characteristics in copper-water heat pipes with screen wick, the 150 and 200-mesh. Recent advances in the miniaturization and large capacity of electronic devices have had a major impact on the design of electronic equipment. As a result, a high-performance cooling system is needed. Experimental variables are inclination angle, number of layer and temperature of cooling water. The distilled water was used for the working fluid. At a inclination angle $6^{\circ}$, the 200-mesh screen wick 3-layer is shown the best heat transfer performance.

• 한국전산유체공학회지
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• 제14권3호
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• pp.9-15
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• 2009

Numerical investigation has been carried out for laminar flow past an inclined square cylinder in cross freestream. In particular, inclination of a square cylinder with respect to the main flow direction can cause sudden shift of the separation points to other edges, resulting in drastic change of flow-induced forces on the cylinder such as Strouhal number (St) of vortex shedding, drag and lift forces on the cylinder, depending upon the inclination angle. Collecting all the numerical results obtained, we propose contour diagrams of drag/lift coefficients and Strouhal number on an Re-Angle plane. This study would be the first step towards understanding flow-induced forces on cylindrical structures under a strong gust of wind from the viewpoint of wind hazards.

• Journal of Astronomy and Space Sciences
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• 제9권2호
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• pp.165-170
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• 1992

$\zeta$ Aur형의 쌍성계인 32 Cyg 에 대해 복사 전달 방정식을 수치적분하여 이론적인 선 윤곽을 구하였다. 원천함수를 구하기 위해 2 준위 원자와 완전 재분배를 가정 하고 Sobolev 근사를 이용하였다. 선 윤곽을 궤도위상에 따라 구한 결과, 공전궤도 위상 0.99에서는 선 윤곽이 적색편이를 보였으며, 공전궤도 위상 0.70에서는 파장이 짧은 쪽으로 약간 치우쳤다. 또한 궤도면 기울기에 따른 효과를 보기 위해 같은 위상에서 각기 다른 기울기를 주고 계산하였는데, 기울기가 작은 경우에 빛의 세기가 증가하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.491-494
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• 2001

This paper presents a utility interactive photovoltaic generation system with the angle of inclination and direction. This paper summarizes the results of these efforts by offering a snapshot of the configuration of photovoltaic in residential applications. The status of PV system components and inter-connection and safety equipment will be summarized, also. This System is able to alteration the angle of inclination and direction. Hence this paper discusses only points that might be useful for application.

• 설비공학논문집
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• 제15권10호
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• pp.787-794
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• 2003

The effect of inclination angle on natural convection heat transfer has been studied for water layers. The range of the Raleigh number was from the subcritical value to 1.4${\times}$10$^{7}$ , and the range of the inclination angle, $\theta$, measured from the horizontal was 0$\leq$$\theta$$\leq$180$^{\circ}$. For horizontal water layers, present results agreed well with the results of previous investigators and also showed significant departures from the results of air layers in the turbulent regime. Inclined cylindrical water layers showed secondary maxima in heat transfer, whereas rectangular air layers showed continuous decline of Nusselt number.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.430-434
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• 2004

The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination to the equivalent conicity relating dynamic behavior. The analyses show the following results. The widening of wheel flange-back distance increase the equivalent conicity, the widening of gage, rail inclination 1/20 compared with rail inclination 1/40 decrease the equivalent conicity.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1394-1399
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• 2004

Recently solar energy is representative in the technology development and spread of alternative energy. Specially in condition of solar collectors, they have had very various shape. This paper reports experimental study about the application of Oscillating Capillary Tube Heat Pipe to flat-plate solar collector. In conclusion, overall temperature distribution of OCHP was investigated by charging ratio and inclination angle. Respective charging ratio is 15%, 20%, 40% and respective inclination angle is horizontal, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, perpendicular. As a result of experiment, charging ratio 20% heat pipe has shown the most uniform temperature distribution and also performance of heat transfer has been the best.

• 자동차안전학회지
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• 제11권1호
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• pp.40-47
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• 2019

First, three point bending analysis for the inclined press door impact beam was carried out to investigate inclination angle effect on the maximum strength with varying support distance. Next, for the system model with spring elements representing body stiffness at door mounting area, the bending structural behavior of impact beam mounted on vehicle was estimated. The mounting distance and inclination angle were changed and the beam bending buckling strength was presumed at the head displacement below which spring stiffness change has little effect on the load. Finally strength ratio to predict the bending buckling strength of impact beam mounted on vehicle from three point bending maximum strength of fixed support distance was suggested.