• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1713-1716
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• 2003

Casing Oscillator is a construction machine that used to insert casings which is based on construction of a building or bridge into the ground. The purpose of using casing supports a pile or in case when heavy loads and moments happens. It is very important that the casings are retaining perpendicular to sea level regardless of the slope of the ground. So it requires that Casing Oscillator keep horizontality. But, it was useless a horizontal control without another heavy equipment. Tornado is a type of Casing Oscillator to advance. It controls horizontality with 4 cylinders. Those cylinders controlled by high-speed solenoid valves. This paper represents horizontal control of the Tornado using Kinematics. First. the horizontal control simulated by AMESim, which is simulation tool. then it compared with experimental results.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.6
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• pp.886-893
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• 2000

The Characteristics of dividing the dispersed bubble, plug, and slug steam-water flow in the horizontal junctions with horizontal branches have been experimentally investigated. The experimental investigation of the separation phenomena in a $45^{\circ}$ horizontal wye with equal pipe inner diameter of 25 mm is presented to provide a data base for the development and verification of the analytical models. The phase separation and pressure distribution in the three legs of each test section are obtained through the set of measurements made in the present work. And the dependence of phase separation on different parameters, such as inlet quality and mass flux, is discussed.

• The Journal of the Acoustical Society of Korea
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• v.2 no.1
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• pp.35-40
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• 1983

수심 65m의 godutr에서 해면으로부터 10m 깊이에 수평 청음기 배열을 설치하여 수중소음의 상 관관계를 측정하였다. 분석은 FFT 방식을 이용하여 63Hz에서 315Hz 까지의 저주파 영역에서 True 상 관계수를 직접 얻었다. Buckingham의 천해모델과 비교한 결과 160 Hz 이하에서는 이론치와 거의 같았 으나 200Hz 이상에서는 이론치와 많은 차이를 보였다. 이는 200 Hz 이상에서 결과치의 Zero-Crossing point 가 이동된 것을 보보인면이나 Kuperman과 Ingenito의 천해 모델에서 NEAR-FIELD의 영향이 Zero-crossing point를 이동시킨다는 사실, 또 주파수가 높아질수록 해상상태의 영향을 받는다는 심해 수중소음의 상관관계에 대한 싫머결과등을 비교해 볼 Eio near-field 소음원의 영향을 무시한채 far-field 소음원의 영향만을 고려한 Buckingham의 천해모델이 갖는 제한성을 나타낸 것이라 볼 수 있다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.11
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• pp.3008-3020
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• 1994

Condensation heat transfer on a single horizontal tube with electric fields (Electro-Hydro-Dynamics, (EHD)) has been studied experimentally. Results are presented for EHD enhanced condensation of R-113 on a single horizontal tube using several electrode geometries. Especially, its attention was focused on the effects of electrode geometry, electric field strength and the gap of the electrode. In this study, single wire, helical, ring and mesh electrode were used. The range of the imposed voltage was 0~20 kV. As the voltage was increased the surface of liquid became an unstable wave, stream jet, liquid column and then liquid extraction in sequence. Among the various kinds of electrodes, the single wire electrode is suitable for practical application.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.12
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• pp.1049-1056
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• 2000

In this study, condensation heat transfer coefficients(HTCs) of 2 nonazeotropic refrigerant mixtures of HFC32/HFC134a and HFC134a/HCFC123 at various compositions were measured on a horizontal smooth tube. All data were taken at the vapor temperature of 39$^{\circ}C$ with a wall subcooling of 3~8K. Test results showed that HTCs of tested mixtures were 11.0~85.0% lower than the ideal values calculated by the mass fraction weighting of the pure components HTCs. Thermal resistance due to the diffusion vapor film was partly responsible for the significant reduction of HTCs with these nonazeotropic mixtures. The measured data were compared against the predicted ones by Colburn and Drew\`s film model and a good agreement was observed.

• Journal of the Korean Geotechnical Society
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• v.31 no.12
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• pp.71-76
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• 2015

Recently, people are increasingly interested in horizontal directional drilling (HDD) to construct oil and gas pipeline and utility pipeline in the urban area as one of trenchless methods. One of major issues during the HDD is the collapse of borehole, which may be the potential causes of ground collapse. This study investigated the effect of mud pressure on the borehole stability, using finite element analysis. Since the borehole is being drilled with a certain angle, three dimensional analysis should be performed. The borehole stability was examined by applying two different types of mud pressures, i.e., uniform and non-uniform, to the exterior surface of borehole. The results show that the high mud pressure at the beginning of drilling, i.e., at shallow depth, causes the borehole collapse, whereas the borehole was stable even at high mud pressure as the drilling depth increases. It can be said that the determination of maximum mud pressure is strongly related to the drilling depth.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.2
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• pp.219-227
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• 2020

Tooth eruption involves a complex developmental process of tooth migration from the dental follicular origin to the final occlusion position in the oral cavity via the alveolar process. Disturbance of tooth eruption can occur at any point in a series of eruption stages; however, horizontal impaction of the mandibular first molar and primary retention of the primary mandibular second molar are rarely observed simultaneously. This study describes the treatment for two cases of horizontally impacted first molar with primary retention of primary molar. The primary retention of the primary mandibular second molar was extracted, and orthodontic traction was applied to the horizontally impacted primary mandibular first molar. Subsequently, displacement of the premolar tooth bud was improved and space regaining for eruption was achieved, guiding to normal eruption of the first molar.

• Proceedings of the SAREK Conference
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• 2006.11a
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• pp.35-35
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• 2006

• 한국가시화정보학회:학술대회논문집
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• 2004.11a
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• pp.5-9
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• 2004

An experimental study is performed turbulent swirling flow behind a crcular cylinder using 2-D PIV technique. The Reynolds number investigated is 15,000. The mean velocity vector, time mean axial velocity, turbulence intensity, kinetic energy and Reynolds shear stress behind the cylinder are measured before and behind the cylinder along the test tube.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1993.07a
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• pp.82-85
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• 1993

해양구조물에 가장 이상적인 구조물의 형태중의 하나는 원형실린더인데, 그것은 같은 재질일 경우 단위무게당 가장 큰 힘을 지지할 수 있는 단면을 가지고 있고 또한 어느 방향으로의 외력에 대해서도 비교적 간단하게 해석할 수 있는 형상을 가지고 있다. 송유관 등의 목적으로 원형실린더를 해저에 설치함으로써 파이프라인이 형성되고, 공학적으로 볼 때 이에 대한 해석은 바닥경계를 고려하여 수평실린더에 작용하는 힘을 구하는 것으로 귀착된다고 할 수 있다. (중략)