• 비파괴검사학회지
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• 제12권3호
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• pp.7-11
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• 1992

Accurate measurement of green density of compacted part in the powder metallurgy industry is rather fundamental but extremely important process that decide the quality of the sintered part. In case of green sheet P/M product, the green density as well as the distribution of the density must be examined for the same reasons. Currently in most cases, density measuring process is being performed applying conventional Archimedes principles. However this method is not only time-consuming but also often inaccurate because of the inherent nature of the process, such as part sectioning, closing of surface porosity with wax and weighing in air and in water. Therefore, it is necessary to develop a faster and more accurate method to measure the density of green sheet P/M product. In this work, a nondestructive density measurement device using gamma-ray absorption principles was constructed and the optimum condition for measuring green density of P/M sheet and its distribution was sought. The results showed that this method was very effective in terms of measuring time and accuracy.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제35권4호
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• pp.425-444
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• 2021

본 연구는 수학적 과정을 고려한 측정 활동의 구성을 통해 측정 영역에서 추구하는 목표에 도달할 수 있다는 가정 아래 초등학교 4학년 학급에 측정 오차를 활용한 삼각형의 내각의 합 지도 방안을 적용하고 결과를 분석하였다. 연구 결과 첫째, 학생들은 측정 오차를 활용하여 삼각형의 내각의 합을 학습함으로써 측정 오차의 발생 가능성을 인식할 수 있었다. 둘째, 측정 오차에 기반한 토론 과정은 학생들이 수학적 정당화를 시도할 수 있는 바탕이 되었다. 셋째, 반원을 활용한 조작 활동은 학생들에게 자연스럽고 직관적인 수학적 정당화의 방법으로 인식되었고 일반화를 이끌었다. 넷째, 측정 오차를 활용한 삼각형의 내각의 합 지도 방안은 학생들의 수학적 의사소통 능력과 수학에 대한 긍정적인 태도의 함양에 기여하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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• pp.194-197
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• 1999

Automatic weld bead removal system is consisted of bead removal tool, bead profile measurement system and tool motion control system. In this paper, design of weld bead profile measurement system which is used for automatic weld bead removal system is described. The system measures the weld bead position, normal vector of the auto-body and weld bead profile. The optical sensor with structured laser beam is used as a sensor and comparison of the sensor that can be used for this purpose is discussed in detail. The measurement process and the related software developed for this purpose are also described. A median filter, average filter and long line filters are used and their effects in bead profile measurement are discussed. The measurement system is integrated into automatic bead removal system and is used to remove weld bead in rear pillar of automotive body. The whole system operates well in automotive body assembly line and thus the system is proved to be good for this purpose.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.235.1-235.1
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• 2014

Precise measurement of plasma parameters including density and temperature is the most essential part for understanding plasma characteristics. To persue more accurate measurement, it is very important to understand the intrinsic error of the measurement method. In this paper, we performed the plasma measurement with different method; langmuire probe and cutoff probe. Both measurement technology are known to be exactly correlate with etch other. We conducted the four set of same experiments process by diffrent persons to observe the intrinsic error based on measurement tools. As a result, the cutoff probe is relatively reliable then the Langmuir probe. This difference is analyzed to be intrinsic since it cames from the inevitable error such as manufacturing of probe tip. From this study, we sure that it is good decision to choose cutoff probe as repeatable measurement independent with intrinsic human factor.

• 한국정밀공학회지
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• 제16권10호
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• pp.172-181
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• 1999

The objective of this research is to develop a measurement error model for sculptured surfaces in On-Machine Measurement (OMM) process based on a closed-loop configuration. The geometric error model of each axis of a vertical CNC Machining center is derived using a 4${\times}$4 homogeneous transformation matrix. The ideal locations of a touch-type probe for the scupltured surface measurement are calculated from the parametric surface representation and X-, Y- directional geometric errors of the machine. Also, the actual coordinates of the probe are calculated by considering the pre-travel variation of a probe and Z-directional geometric errors. Then, the step-by-step measurement error analysis method is suggested based on a closed-loop configuration of the machining center including workpiece and probe errors. The simulation study shows the simplicity and effectiveness of the proposed error modeling strategy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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• pp.416-418
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• 2000

Thin films of phase-pure perovskite $(Pb_{0.72}La_{0.28})Ti_{0.93}O_3$ (PLT) were deposited in-situ onto Pt/Ti/$SiO_2$/Si substrates by pulsed laser deposition. We have systematically investigated the variation of grain sizes depending on the process condition. Both in-situ annealing and ex-situ annealing treatments have been compared depending on the annealing time. The grain sizes of PLT thin films were successfully controlled 260 to 350 nm by changing process parameters. Microstructural and electrical properties of the film were investigated by C-V measurement, leakage current measurement and SEM. Two-step process to grow $(Pb_{0.72}La_{0.28})Ti_{0.93}O_3$ (PLT) films was adopted and verified to be useful to enlarge the grain size of the film and to enhance the leakage current characteristics.

• 디지털산업정보학회논문지
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• 제15권4호
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• pp.63-70
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• 2019

The subject of the simultaneous measuring system of base pattern and deposition pattern is a new research topic on a defect inspection of OLED. In this paper, we propose a new OLED inspection method that simultaneously measures standard and deposition pattern images. This method reduces unnecessary processes and tac time during OLED inspection. For an additional reduction of the tac time during pattern measurement, the ROI was configured to measure only in the designated ROI area instead of measuring the entire area of an image. During the ROI set-up, the value of effective deposition pattern area is included so that if the deposition pattern is out of the ROI zone, it would be treated as a defect before measuring the size and center point of the pattern. As a result, the tac time and inspection process could be shortened. The proposed method also could be applied to the OLED manufacturing process. Production of OLED could be increased by reducing tac time and inspection process.

• 상하수도학회지
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• 제19권2호
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• pp.214-220
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• 2005

Errors may occur due to analysis methods and water quality during the application of the on-line particle counter In water treatment process. Errors caused by analysis methods include particle destruction by shear force due to inflow speed and tube friction, as well as interruption by screening, bubbles and contaminants. Since errors happen frequently because of these factors, it is necessary to examine and evaluate such errors during the application of a particle counter. Errors can be large due to screening and bubbles. Measurement values are effective for water analysis after filtration process. However, because of screening, only measurement values for particles above $7{\mu}m$ are valid for water with a turbidity between 3-10NTU. As particle numbers around $10{\mu}m$ increase a lot after ozone treatment, sufficient pretreatment process is necessary. Physical conditions should keep stable for inflow to decrease errors caused by shear force.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.566-569
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• 2006

The purpose of this study is to develop digital air meter used pressure sensor for measurement of air content in freshly mixed concrete by pressure method. The digital air meter can enhanced measurement accuracy and uniformity of air content in freshly concretes, according to use of pressure sensor and measuring process automation. Finally, the digital air meter in this study is improved reproducibility and reliability of measurement compared with analog air meter.

• 대한안전경영과학회지
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• 제7권4호
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• pp.141-163
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• 2005

The international SPICE (Software Process Improvement and Capability determination) Project ISO/IEC 15504(SPICE : Software Process Improvement and Capability determination) is an emerging International Standard on SPA(Software Process Assessment). A prime motivation for developing this standard has been the perceived need for an internationally recognized software process assessment framework that pulls together the existing public and proprietary models and methods. A SPICE assessment can be considered as one of representative SPA model since assessors assign ratings to indicators and metrics to measure the capability of software process. But this models doesn't provide a systematic measurement procedures and dynamic method for SPI(Software Process Improvement). Through the evaluation of SPICE is capable of providing a substantiated basis for using the notion of capability, as well as providing information for nacessary improvements to the standard using 6sigma process. As a result, this paper propose a measurement procedure and guidelines for application of 6sigma process to guarantee the reliability in SPI and suggest the structure to support SPI on overall organization.