• The KSFM Journal of Fluid Machinery
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• v.6 no.2 s.19
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• pp.23-28
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• 2003

ADC (Automatic Discharge Connector) is commonly used for the easy maintenance of the submersible pumps. However, the small gap between the flange of the base plate and that of the pipe due to the head rise, the flow momentum change and the mis-installation make a leakage flow that may be a great loss to the pumping system. In this study, the performance degradation was predicted with the simple leakage flow model through the gap. The newly developed ADC was tested, and the leakage performance was compared with the old one and also no-leakage piping system. The newly developed ADC reduced the leakage flow in a satisfactory way in comparison with the old model.

• 유체기계공업학회:학술대회논문집
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• 2000.12a
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• pp.65-74
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• 2000

A five path ultrasonic and/or magnetic flowmeter were installed after valve. Five path ultrasonic flowmeter were tested to obtain it's performance in a water flow standard system and magnetic flowmeter. It's varied with straight pipe length(nD), install direction and valve position. All the results are summerized. The multi-path flowmeters(MUF) showed up to $\pm0.5{\%}$ at a 2, 4, 8, 15D spacing : the MUF was significantly better than magnetic flowmeter at disturbed flow conditions.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.61-64
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• 2006

Recently the development of small hydropower generation with using water pipes is revitalized by the water works facilities. However, when the tubine generator is in case of emergency stop by the internal and external accidents, it causes water hammer in water pipes and suspension of water supply. To prevent these problems of small hydropower generator, we has analyzed water supply patterns, installation position and water pipe systems.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.862-867
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• 2000

The auxiliary engine exhaust noise in ships are directly transmitted to bridge wing with the only distance attenuation. It is not so practical that no special treatment can be applied between exhaust pipe and bridge wing in order to reduce the transmission of the exhaust noise. In general, a silencer is fitted to reduce the exhaust noise and also noise of bridge wing. The silencer should be properly designed under the consideration of the frequency component of the exhaust noise and the required insertion loss. In this paper, the frequency component of exhaust noise of various engines are compared and a design and a design and installation of silencer to reduce low frequency is introduced.

• 한국전산유체공학회:학술대회논문집
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• 1997.10a
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• pp.143-148
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• 1997

Differential pressure Venturi cone flowmeter is an advanced flowmeter which has many advantages such as wide range of measurement, high accuracy, excellent flow turndown ratio, low headless, and short installation pipe length requirement, etc. Like other differential pressure flowmeter, Venturi cone flowmeter uses the law of energy conservation, but its shape and position make it perform better than others. The cone acts as its own flow conditioner and mixer, fully conditioning and mixing the flow prior to measurement. For the analysis, we use Reynolds-averaged Navier-Stokes equations and $k-{\omega}$ turbulence model. The equations are fully trans-formed in the computational coordinates, the pressure-velocity coupling is made through SIMPLER algorithm, and the equations are discretized using analytic solutions of the linearized equations(Finite Analytic Method). At the end of the paper, using the result of analysis, We propose a new shape of cone with the hope of drag reduction and high performance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.39-40
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• 2012

Construction IT convergency proposes advanced management abilities of a construction project. Sensing data provided by various sensor technologies can be utilized for diverse management areas. This study analyzes required functions of sensors for implementing time, cost, safety and quality management, focusing on the ground works including excavation, pipe installation, retaining wall etc. Therefore, this study first generates essential management areas, analyzes cutting-edge sensor technologies appropriated for the areas, and finally proposes a matrix system that represents relationships between the management areas and sensor technologies, The proposed system is expected to reinforce construction management abilities by integrating sensor technologies.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.671-672
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• 2006

Recently the development of small hydropower generation with using water pipes is revitalized by the water works facilities. However, when the tubine generator is in case of emergency stop by the internal and external accidents, it causes water hammer in water pipes and suspension of water supply. To prevent these problems of small hydropower generator, we has analyzed water supply patterns, installation position and water pipe systems.

• Proceedings of the KIEE Conference
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• 2005.04a
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• pp.19-21
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• 2005

자기누설탐상시스템은 비파괴 검사의 한 방법으로 검사 대상물체를 자화시켜 부식이나 결함부위에서 자기누설을 측정하는 방법으로 Magnetic Flux Leakage(MFL) PIG는 자기누설 탐상시스템을 가스관에 적용하여 결함 유 무를 검사하는 시스템이다. 가스관에는 결함이외에 가스공급을 위해 필요한 여러 가지 구조물이 있으며 이러한 구조물은 부식이나 결함에 의해 발생하는 자기누설과는 구별이 된다. 따라서 가스관의 구조물과 결함을 구분하기 위하여 가스관의 구조물에 대한 자기적 영향 해석과 결함 신호와의 차이점을 비교, 분석하였다.

• Corrosion Science and Technology
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• v.15 no.6
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• pp.320-325
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• 2016

To perform ultrasonic testing (UT) thickness measurement of the secondary side piping installed in nuclear power plants, the insulation for preventing heat loss should be removed. The type of insulation can be divided into fixed and removable insulation. Fixed and removable insulation have their own strengths and weaknesses. Removable insulation has been installed in the components susceptible to wall thinning caused by FAC and erosion from Shin-Kori unit 1, which commenced its commercial operation in 2011. In this paper, the number of repeated inspections of components and the number of replacements of fixed insulation were estimated and a more economical way was identified based on the manufacturing and installation costs for fixed and removable insulation.

• 유체기계공업학회:학술대회논문집
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• 1999.12a
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• pp.114-117
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• 1999

Five-path ultrasonic flowmeters (200 and 300 mm diameters) were tested to obtain it's characteristics in a water flow standard system. A five-path ultrasonic flowmeter was installed after various pipe fittings (elbow, valve, tee) or a pump. The distance between flow disturbance source and a flowmeter was main experimental parameter. Without a flow conditioner, a five-path ultrasonic flowmeter shows good characteristics as the distance between flow disturbance source and a flowmeter is longer than 10 diameter of a flowmeter.