• 한국지반공학회지:지반
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• 제10권4호
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• pp.39-52
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• 1994

지반앵커의 설계시 가장 중요한 것은 극한인발력을 구하는 것이다. 앵커의 간격이 가까울 때는 앵커의 인발에 따른 지반 거동의 중첩 현상, 즉 군효과가 발생하여 앵커 1개당 극한인발력이 감소하게 된다. 현재까지 앵커의 군효과에 대한 연구가 극소수인데 그것도 대부분 연직 앵커에 관한 것으로 경사앵커에 대한 연구는 거의 없는 실정이다. 이 이유는 지반앵커의 인발에 따른 지반 거동의 관찰과 앵커표면 마찰응력을 정확하게 측정해서 분석할 수 있는 실험과 이론적 고찰이 대단히 어렵기 때문일 것이라고 생각한다. 본 연구는 공기 건조 모래지반 내에 설치된 경사 지반앵커의 군효과에 대한 모형실험에 관한 것으로, 앵커체 깊이 방향으로 부착된 10개의 변형률게이지에 의해서 앵커체 표면의 마찰응력을 구하여 군효과에 의한 마찰응력의 감소에 대해 분석하는 것이다. 실험 결과, 앵커표면간 거리가 10.7cm에 불과한 대단히 가까운 앵커의 경우에도 군효과에 의한 마찰응력의 감소와 극한인발력의 감소는 보이지 않는다. 그러나 본 연구는 건조모래 지반내의 소규모 실내모형실험에 한한 것이므로 이후 여러 가지 지반 조건하에서의 모형실험과 현장실험을 실시해서 보다 일반적으로 적용될 수 있는 연구가 지속되어야 할 것이다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 춘계학술대회 논문집
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• pp.108-119
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• 2001

The Spectral Analysis of surface Waves(SASW) Method has a great has a great potential for rapid determination of shear wave velocity profile of ground. However, it has an inherent limitation in the interpretation of test results due to the assumption that the ground is layered horizontally. The reason of the assumption is that difficulties exist in obtaining analytical solutions of wave equation when a soil system is composed of inclined soil layer. In this study, a finite-element method has been employed to assess the effects of dip angle and stiffness contrast of inclined soil layers and the testing direction on the dispersion curve. The propagation of wave front in the inclined soil layer was also investigated. The results indicated that the influence of dip angle on the dispersion curve is getting obvious as the dip angle increases and the propagation of wave front in the inclined layer also entirely different compared with the case of the horizontal layer.

• 한국안전학회지
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• 제15권1호
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• pp.36-42
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• 2000

An experimental study was carried out to investigate the effects of inclined angles of channel on thermal stability of electronic components. In this study, it is focused on the natural convection heat transfer from an inclined parallel channel with discrete protruding heat sources. The material used for the inclined parallel channel was epoxy-resin, while air as the cooling fluid. Heat transfer phenomena for inclined angles of $\psi$=$15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$ and for the range of $9.52{\times}10^5/ were analyzed. The thermal fields in the channel were visualized by Mach-Zehnder interferometer. Also, local temperatures were measured by thermocouples along the channel wall and heat sources surface. As a result, for the range of $4.29{\times} 10^5/, a useful correlation of mean Nusselt number was proposed as a function of modified channel Rayleigh number.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.143-146
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• 1995

Due to the recent growth of die/mold machining industry, demands for the high-precision and the high0quality of die product are increasing rapidly. Free surfaces of die/mold are often manufactured using the ball-end milling process. It is difficult to find the cutting condition of the ball-end milling process due to the free form machining for the various tool paths on inclined surface.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 추계학술대회 논문집
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• pp.23-24
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• 2010

• 대한설비공학회지:설비저널
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• 제8권4호
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• pp.254-259
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• 1979

Radiation data on south-facing surfaces required for the simplified design pro cedures for solar energy systems, have been computed using the method by Liu and Jordan. For the five localities of South Korea selected from reference 6, the factor R for the conversion of the monthly average daily total radiation on a horizontal surface to that on an inclined surface is presented in Table 5. For the other localities, the convession factor R can by computed using Table 2 through Table 4.

• 지질공학
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• 제16권3호
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• pp.255-263
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• 2006

지표가 불규칙한 지형에서 경사시추공을 이용한 단극-쌍극자 배열 전기비저항 토모그래피 탐사를 보면, 우리는 시추공안에 있는 전류원과 지표의 지형기복 사이의 최단거리에 위치한 전위전극에서의 극성변화, 지형기복에 따른 거리계수와 포텐셜의 변화 및 모델링에서 경사 시추공에 위치한 전극과 절점의 공간적인 불일치 등을 고려할 수 있다. 요소분할 방법은 시추공이 곡선이거나 경사져 있을 경우와 하나의 요소에 여러 개의 전극이 있을 때 각 전극에 대한 절점 좌표를 지정할 수 있기 때문에 매우 효과적인 방법이라고 본다. 시추공과 지형기복이 동일한 경사를 갖는 경우에서의 역산 결과는 매우 좋은 영상으로 나타났으며 최소자승근의 오차가 안정적으로 수렴되는 경향을 보였다.

• 설비공학논문집
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• 제13권9호
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• pp.860-867
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• 2001

Absorption of water vapor into LiBr-$H_2O$ O solution flowing over a finned inclined surface is numerically investigated. The momentum, energy, and diffusion equation are numerically solved using a finite difference method. The four different shapes of the wall surfaces are considered to find the best surface for absorption assuming that the wall temperature and the surface tension are constant. The effects of the fin interval and Reynolds number are investigated. Based on the numerical results, it is known that the parabolic surface shows better absorption performance than the other surfaces, and that water vapor absorption increases gradually with decreasing the fin interval.

• 대한기계학회논문집
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• 제19권9호
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• pp.2114-2121
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• 1995

Surface generation model of three types of endmills is introduced to analyse the cutting mechanism of an endmill more accurately. Superposition method is introduced to define the effective cusp including the effects of cutter mark. Through the comparison of three endmills, it is shown that the ball-nose endmill is superior to the ball endmill and the flat endmill for inclined milling process in 3-or 5-axis machining modes. By using the objective function minimizing the machining time, appropriate nose radius is selected for various cutter radiuses and cutter inclination angles.

• Ocean Systems Engineering
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• 제10권1호
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• pp.49-65
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• 2020

In this study, the effects of inclined shaft angle on the hydro-acoustic performance of cavitating marine propellers are investigated by a numerical method developed before and Brown's empirical formula. The cavitating blades are represented by source and vortex elements. The cavity characteristics of the blades such as cavitation form, cavity volume, cavity length etc., are computed at a given cavitation number and at a set advance coefficient. A lifting surface method is applied for these calculations. The numerical lifting surface method is validated with experimental results of DTMB 4119 model benchmark propeller. After calculation of hydrodynamic characteristics of the cavitating propeller, noise spectrum and overall sound pressure level (OASPL) are computed by Brown's equation. This empirical equation is also validated with another numerical results found in the literature. The effects of inclined shaft angle on thrust coefficient, torque coefficient, efficiency and OASPL values are examined by a parametric study. By modifying the inclination angles of propeller, the thrust, torque, efficiency and OASPL are computed and compared with each other. The influence of the inclined shaft angle on cavity patterns on the blades are also discussed.