• 한국측량학회:학술대회논문집
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• 한국측량학회 2007년도 춘계학술발표회 논문집
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• pp.51-54
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• 2007

This study is aimed to acquire the depth information and measure the water volume of reservoir using the robot-ship equipped with GPS and echosounder. Robot-ship is an automatic system for measuring exact depth and bed topography. According to field experiment results, measured water volume by the robot-ship data was not much exceeding 6.8% in comparison with existing water volume data, and it was guessed because of sediments of reservoir bottom. The robot-ship could be used to acquire economically and exactly the water depth and bed topography of reservoirs, dams, rivers and so on.

• 대한기계학회논문집A
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• 제24권1호
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• pp.250-258
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• 2000

The reinforcing effects of ductile short-fiber reinforced brittle matrix composites are studied by, measuring flexural strength, fracture toughness and impact energy as functions of fiber volume fraction and length. The parameters of fracture mechanics, K and J are applied to assess fracture toughness and bridging stress. It is found that fracture toughness is greatly, influenced by the bridging stress ill which fiber pull-out is occur. For the reinforcing effects as functions of fiber volume fraction($V_f$ = 1, 2, 3 %) and length(L = 3, 6. 10cm), the flexural strength is maximum at $V_f$ = 1% and both fracture toughness.

• 한국산업융합학회 논문집
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• 제6권3호
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• pp.193-200
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• 2003

In the production of internal combustion engines, there has been a move towards the development of high performance engines with improved fuel efficiency, lighter weight and smaller sizes. These trends help to answer problems in engines related to thermal load and abnormal combustion. In order to investigate these problems, a thin film-type probe for instantaneously measuring temperatures has been suggested. A method for manufacturing such a probe was established in this study. The instantaneous surface temperature of a constant volume combustion chamber was measured by this probe and the heat flux was obtained through Fourier analysis. In order to thoroughly understand the characteristics of combustion, the authors measured the wall temperature of the combustion chamber and computed heat flux through a cylinder wall while varying the protrusion height of the probe. For achieving the above goals, a instantaneous temperature probe was developed, thereby making possible the analysis of the instantaneous temperature of wall surface and the detection of unsteady heat flux in the constant volume combustion chamber.

• Journal of Chest Surgery
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• 제18권1호
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• pp.19-23
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• 1985

There are several factors influencing post-operative mortality in Tetralogy of Fallot, such as degree of RV outflow tract obstruction, combined anomaly, and age of the patient. Another factor is preoperative left ventricular volume reported by Kirklin and Graham in 1978. From March to September, 1984, 10 patient with Tetralogy of Fallot have been taken biplane cinecardioangiography [LAO and RAO projection] for measuring left ventricular volume by area-length method. The mean age of the patients was 84.9 [S.D.] and 3 males and 7 females were there. Mean value of left ventricle was 62.9ml/m2, which was no statistically difference from normal value. [p value=0.08]. In conclusion, though this study suggests that there is some decrease of left ventricular end-diastolic volume in Tetralogy of Fallot preoperatively as compared with normal individuals, further evaluation is needed to make it confirmatory with more number of patients and lesser range of age of the patients submitted to the study.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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• pp.257-260
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• 1997

In order to investigate the volume resistivity on the electrical properties of transformer oils, the Transformer oils contained BTA is prepared, which was classified by the contents of BTA, such as 1[ppm], 10[ppm], 20[ppm], 30[ppm], 50[ppm], respectively. To measure the physical properties of transformer oils contained BTA, Fourier Transform Infrared Spectroscopy is investigated. And for the study of electrical properties is made by measuring the volume resistivity of each specimen. As result of this experiments, it is confirmed that the volume resistivity characteristics of specimen contained BTA 10[ppm] is superior.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.561-564
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• 2006

The tensile characteristics of four types GFRP (glass fiber reinforced polymer) reinforcing bars with different resin mix proportions and fiber volume fraction were analyzed experimentally. Four types of GFRP reinforcing bars containing approximately 66 or 70% fiber volume fraction with A or B rein mix proportions were considered in this test. All testing procedures including specimens preparation, set-up of test equipments and measuring devices were made according to the recommendations of CSA Standard S806-02. From the test results, it was found that GFRP reinforcing bars containing approximately 70% fiber volume fraction with A rein mix proportion showed the higher tensile strength than that of the others due to the higher fiber volume fraction and proper resin mix proportion.

• Journal of Advanced Marine Engineering and Technology
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• 제33권3호
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• pp.378-386
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• 2009

The effect of fuel mixing on soot structure with methane, ethane, and propane to ethylene-base counterflow diffusion flames has been investigated by measuring the volume fraction, number density, and particle size of soot by adopting the light extinction/scattering techniques. The experimental result showed that the mixing of ethane and propane in ethylene diffusion flame increased soot volume fraction while the mixing of methane decreased. As compare to the ethylene-base flame, the diameters of soot particles for mixture flames are slightly smaller. While the soot number densities for the mixture flames are much higher. Thus, the increase in the soot volume fraction can be attributed to the appreciably increased soot number density by the fuel mixing.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.211-215
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• 1996

In this paper, the volume resistivity of transformer oil is made researches so that the electrical properties for transformer oil is investigated. The specimen is produced by the irradiation of electron beam classified into the low dose, such as 0.5[Mrad], 1[Mrad], 2[Mrad]. The effect of electron team irradiation is studied by investigating the electrical properties of dielectric liquid due to the difference of electron beam dose. To measure the physical properties of transformer oil, courier Transform-Infrared Spectroscopy is investigated. And the study far the electrical properties is made by measuring the volume resistivity of each specimen. By means of the result from this experiments, it is introduced that the movement of carrier to contribute to the volume resistivity on the electrical properties.

• 소음진동
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• 제9권5호
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• pp.943-948
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• 1999

This paper proposes a feasible and effective method for measuring the mechanical-acoustic transfer function by the application of equivalent area and velocity transfer function, a manifestation of the vibro-acoustical reciprocity principle. On the contrary to the volume velocity used in traditional method, the equivalent area is a peculiar raidation characteristics of sound sources and not influenced by any input signal for driving sound source. This invariant property of equivalent area can get rid of boresome works to measure the volume velocity of a sound source every time the driving signal is changed. Moreover, this method has a remarkable advantage to use a general loudspeaker as an accoustic exciter without the assumption of point source and can be applied to all kinds of sound sources even if they are not omni-directional sources.

• 한국자동차공학회논문집
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• 제9권4호
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• pp.27-33
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• 2001

In this study, it is observed that the distribution of combustion chamber volume affects the volumetric efficiency. The distribution ratio was adjusted by controlling combustion chamber volume of head and piston bowl one. Four cases were investigated, which are the combination of different distribution ratios and different compression ratios (9.8-10.0). A commercial SOHC 3-valve engine was modified by cutting the bottom face of the head and/or replacing the piston by the one that has different volume. The result shows that the less the head side volume, the more volumetric efficiency is achieved under the same compression ratio. It is also observed that increasing volumetric efficiency results in early knock occurrence due to increased "real" compression ratio. To consider reliability in estimating the volumetric efficiency, we examined the sensitivity of the AFR equation to possible errors in emission measurements. It is shown that the volumetric efficiency, which is calculated by measuring AFR and fuel consumption, can be controlled in 1% error. 1% error.