• 한국연소학회지
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• 제5권1호
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• pp.91-98
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• 2000

We investigated a uniform temperature zone, produced by double flame structure of a co flow CH4/air partially premixed flame, to be used as a temperature calibration source for laser diagnostics. A broadband N2 CARS(coherent anti-Stokes Raman spectroscopy) system with a modeless laser was used for temperature measurement. When the stoichiometric ratio was 1.5, we found the uniform temperature zone in radial direction of the flame of which the averaged temperature was 2110 K with standard deviation 24 K. In the stoichiometric ratio range between 2.0 and 2.5, we found very stable temperature-varying zones in vertical direction at the center of the flame. The size of the zone was approximately 15 mm and it covered a temperature range from 300 K to 1900 K. We also suggest that this zone can be used as a calibration source for 2-D PLIF(planar laser induced flurescence) temperature measurement.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1997년도 춘계연구발표회 논문개요집
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• pp.100-101
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• 1997

• 산업기술연구
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• 제22권A호
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• pp.67-72
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• 2002

A technique for alignment to true north is presented, based on synchronized measurements of vision image by a camera and output voltage of wind direction sensor. The true wind direction is evaluated by means of image processing techniques with least square sense, and then evaluated true value is compared with measured output voltage of the sensor. The proposed technique is applied to real meteorological tower m Daekwanryung test site. In addition, some uncertainty analysis of this method is presented.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1966-1970
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• 1991

The self-mixing type semiconductor laser Doppler velocimeter(SM-LDV) is applied to measure two simultaneously moving targets with different velocities in the same direction as a prototype target for multiscatterers. The measured beat waveform is found to be a composite wave of each beat waveform measured fran each of only moving target. In the composite waveform, each one-cycle wave has a feature of the sawtooth wave. This fact shows a possibility to discriminate the flow direction of fluid containing multiscatterers with distributed velocities by cooperating an improved version of the direction discrimination circuit already devised by the authors.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.393-396
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• 1996

The electrical characteristics of stearic acid LB films far the horizontal direction were investigated to develop the gab sensor using LB films. $\pi$ -A isotherm was measured to transfer stearic acid on slide glass substrate and surface pressure for optimal deposition was 25[dyne/cm]. The deposition status of stearic acid LB films was verified by the measurement of capacitance which was increased with the number of layers. The thickness of electrode was estimated about 1000 by the I-V characteristics far the horizontal direction. The Conductivity of stearic acid LB films for horizontal direction was 10$^{-8}$ [S/cm] that mean like semiconductor.

• 한국환경복원기술학회지
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• 제11권1호
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• pp.33-38
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• 2008

To investigate the building wind characteristics of skyscraper nearby areas, two points were selected and the wind speed and the wind direction data were measured using 2-D ultrasonic anemometer and propeller type wind monitor during the winter time. The study site is Dohgok-dong, Seoul. After measurement, wind data whose speed is equal to or more than Beaufort level five were selected, classified and analyzed in terms of direction, velocity level and hourly difference. The prevailing wind point is higher than street canyon in terms of intensity and frequency. The main direction is also different. This study aims to figure out the phenomena of building wind impact and also to provide essential basic data for establishing proper guidelines in building wind impact assessment for skyscrapers in Korea.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.499-500
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• 2006

The salt contamination on the distribution facilities was investigated with the wind direction and velocity. Most previous researches were concentrated on the measurement of The Equivalent Salt Deposit Density(ESDD) without environmental consideration. The wind direction and velocity of the many environmental conditions are the most important factors to analyze salt contamination. Pohang area which is located on the south and east of the Korean Peninsula was chosen to do this research. This research will present the result of ESDD depending on the wind direction and velocity.

• 한국정밀공학회지
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• 제12권12호
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• pp.130-138
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• 1995

Machined graphite/epoxy surfaces were studied by using SEM (Scanning Electron Microscopy), surface profilometry and its analysis to determine suitable surface describing parameters for machined unidirectional and multidirectional laminate composite. The surface roughness and profile are found to be highly depdndent on the fiber layup direction and the measurement direction. It was possible to machine 90 .deg. and -45 .deg. plies due to the adjacent plies, which were holding those plies. It was found that the microgeometrical variations in terms of roughness parameters $R_{a}$ without $D_{y}$(Maximum Damage Depth) region and $D_{y}$are better descriptors of the machined laminate composite surface than commonly used roughness parameters $R_{a}$and $R_{max}$ The characteristics of surface profiles in laminate composite are well represented in CPD (Cumulative Probability Distribution) plot and PPD (Percentage Probability Density) plot. Edge-trimmed multidirectional laminate surfaces are Gaussian and random for profiles measured along the tool movement direction, they are periodic and non-Gaussian in the direction perpendicular to the tool movement.t.ent.t.

• 센서학회지
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• 제15권6호
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• pp.442-448
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• 2006

Ultrasonic anemometers using pulse envelope detection-based method are standard instruments in most meteorological studies. In this paper, a new phase measurement method is tried to achieve the enhanced resolution without changing dimensions. The measurement sensitivity, dynamic range, and measurement speed of the new instrument are 0.2 mm/s, 13.3 m/s, and 13 measurements/sec, respectively. A graphic user interface is added to show the velocity and direction of the wind with the speed of sound and temperature of the wind in the 3 dimensional space. The new anemometer could be useful for the measurement of the air speed, the flow of fluids, and even air flow inside the downtown buildings.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.61-63
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• 2001

Residual stress distribution in injection-molded short fiber composites was determined using layer-removal method. Polysterene with 3 vol% carbon fibers was injection-molded into the tensile specimen. With milling machine layer-removal process was conducted and the curvature data were acquired. Treuting and Read analysis which is assuming isotropic material, and White analysis considering anisotropy due to the fiber orientation were used to calculate residual stress of the flow direction through the thickness direction and compared with each other.