• 대한기계학회논문집
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• 제18권7호
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• pp.1873-1880
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• 1994

Fully developed turbulent flow in a circular pipe and laminar boundary layer on a flat plate were measured to develop a measuring technique of the wall sheat stress using Preston tubes. New empirical formulas to extimate displacement factor of Preston tube obtained through the present study. The displacement factor for turbulent flow was considerably different from that for the laminar flow. Measured wall shear stress was not pretty dependent on the displacement factor for Preston tubes in the inertia sublayer of turbulent boundary layer, however was considerably affected in the laminar boundary layer. Measuring error of skin friction using the CPM technique was 3% for turbulent and 5% for thin laminar boundary layers.

• 대한기계학회논문집
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• 제19권5호
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• pp.1333-1339
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• 1995

Recently developed technique of measuring minor species concentration by using the modulation dip in broadband CARS has been applied to the flame structure study of methane/air premixed flames in a counterflow. This method used the modulation dip from the cold band CO Q-branch resonant signal superimposed on the nonresonant background. The measured CO concentration profile in a symmetric and unsymmetric methane/air premixed flames together with the velocity and temperature by using LDV and CARS have been compared with the numerical results adopting detailed chemistry modeling. The results show that there is a satisfactory agreement between the experimental data and numerical results for velocities, temperatures and CO concentrations. And the modulation dip technique of measuring minor species, such as CO is a viable tool for a quantitative measurement in a flame.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
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• pp.210-213
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• 2005

This article describes an estimate method of the spark plug gap by measuring breakdown voltage. Breakdown voltage is the function of spark plug gap, pressure, temperature and humidify. However. It is dominated mainly by the spark plug gap. This technique is applied to in-line process test of the spark plug gap in automobile engine production. Breakdown voltage of normal spark plugs slightly scatters in ordinary conditions and if there is dust or burr in the gap, breakdown voltage gets lower. This technique saves repairing time for bad spark plug and attributes to improve the quality of automobile engine.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.159-165
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• 2012

The accurate focusing position should be determined for accurate measurements In VMS. Camera lens focusing is an important problem in computer vision and video measuring systems (VMS) that use CCD cameras and high precision XYZ stages. Camera focusing is a very important step in high precision measurement systems that use computer vision technique. The auto focusing process consists of two steps, the focus value measurement step and the exact focusing position determination step. It is suitable for eliminating high frequency noises with lower processing time and without blurring. An automatic focusing technique is applied to measure a crater with a one-dimensional search algorithm for finding the best focus. Throughout this paper, the suggested algorithm for the Auto focusing was combined with the learning. As a result, it is expected that such a combination would be expanded into the system of recognizing voices in a noisy environment.

• Journal of Biosystems Engineering
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• 제17권4호
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• pp.404-409
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• 1992

It is important to measure the somatic informations for stockbreeding automatization. This study was carried out for the development of wireless measurement system of sphygmus in living animals. In meauring sphygmus counting with the single-channel telemety system, a LED-photo transistor sensor showed more sensitivity to the change of blood pressure than a piezo-electric sensor based pressure sensor. The LED-photo transistor sensor resulted ${\pm}1.29%$ of measurement error of sphygmus counting. In the process of transmitting and receiving the blood pressure signal for counting sphygmus, noises were mixed with, and the noises made the counting almost impossible. Auto-correlation analysis technique was applied to the signal data to extract the sphygmus information, and the technique was proved to be very effective.

• 한국정밀공학회지
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• 제32권2호
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• pp.191-198
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• 2015

In this paper, six-degree-of-freedom (DoF). Displacement measurement technique using a compact stereo-vision system is proposed. The measuring system consists of a camera, an optical prism, two plane mirrors, and a planar marker on a target. The target was attached on an object so that its six-DoF displacement can be calculated using a proposed coordinates estimating algorithm and stereo images of the marker. A prototype was designed and fabricated for performance test. From the test results, it can be confirmed that the proposed measuring technique can be applied to monitoring and control of various manipulators.

• Smart Structures and Systems
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• 제2권3호
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• pp.275-293
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• 2006

For health monitoring purpose usually the structure is instrumented with a large scale and multichannel measurement system. In case of highway bridges, operating vehicle could be utilized to reduce the number of measuring devices. First this paper presents a static damage detection algorithm of using operating vehicle load. The technique has been validated by finite element simulation and simple laboratory test. Next the paper presents an approach of using this technique to field application. Here operating vehicle load data has been used by instrumenting the bridge at single location. This approach gives an upper hand to other sophisticated global damage detection methods since it has the potential of reducing the measuring points and devices. It also avoids the application of artificial loading and interruption of any traffic flow.

• 대한안전경영과학회지
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• 제7권4호
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• pp.27-38
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• 2005

In manufacturing industry of the modem industrial society, people increasingly become concerned the awareness of safety increasingly although they have regarded production the most important factor. Even though, as people make efforts on accident preventions, the number of accidents is decreasing, fatal major industry accidents are rather thanincreasing so that the number of deaths has not decreased. Under these conditions, there is an attempt to introduce and perform the process safety management system as a means for keeping from major industry accidents. However, it leaves to be desired on the methods of measuring process safety in the general manufacturing industry, while it is available to do that in the chemistry industry. Therefore, in this paper, we analysis processes of manufacturing industry in safety point of view and suggest the technique efficiently measuring and managing each process. Proposed the technique shows that the specification on safety determines AHP weight through the managers of firms and each process is suggested by using normalized matrix.

• 한국군사과학기술학회지
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• 제2권2호
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• pp.157-165
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• 1999

Production and measurement of a super-polished few-ppm-scattering mirror substrate are investigated. In order to improve the surface roughness directly determining scattering, the super-polishing process using Bowl-Feed technique is tried. The surface quality of the super-polished substrate is estimated by the phase-measuring interferometer. For the reliable roughness measurement using the interferometer, data averaging method is applied so that the optimal data averaging condition, 30 phase-data averaging and 20 intensity-data averaging, minimizing the measurement error is experimently searched. Based on the optimal data averaging condition, surface roughness of home-made mirror substrate is measured to be less than $0.5{\AA}$ rms corresponding to 2-ppm total-integrated-scattering.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.491-494
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• 2000

Conductive Langmuir-Blodgett(LB) films have recently attracted much interest from the viewpoint of ultrathin film conductors at the molecular level. The result shows that the Maxwell-displacement-current(MDC) measuring technique is useful in the detection of phase-transition over the entire range of molecule areas. At the liquid-solid phase transition, a striking feature in the present current measurement was observed; the I-A isotherm for a DPPC monolayer has sharp bend. Dynamic behavior of monolayers in the presence of an external field was also investigated using the current-measuring technique. Dynamic behavier of DPPC monolayer was measured by displacement current when the molecules are stimulated by pressure velocity. As result, it is known that current is generated of higher current pe마 as compression velocity become faster. Also, in order to clarify the reorganization of the lipid monolayers, it is instructive to plot the relationship between I and 1/$A^2$.