• 제목/요약/키워드: measurement method

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석유화학 플랜트 EPC 사업의 진도율 산정표준의 제안 (A Standard Method for Progress Measurement in a Petrochemical Plant EPC Project)

  • 조홍연;유호선
    • 플랜트 저널
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    • 제7권4호
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    • pp.77-87
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    • 2011
  • In proportion to continuing growth of overseas plant market and the trend of its mega scale of the project, the importance of management is significantly emphasized for the successful execution of the project. And it is recognized that progress control is the most important management item amongst the others in the management. Progress control is importance of progress measurement for performance measurement and process control of project, but it is hardly obtainable securing the objectivity in the progress measurement since the progress measurement are being applied differently in accordance with the project conditions and the experience level of the person in charge for the progress control. This study has conducted as following to propose a standard method for progress measurement in a petrochemical plant protect. Domestic and overseas plant projects are investigated variously with the applied method of progress measurement, and the deduced problem of progress measurement. And then standard method for progress measurement of engineering, procurement, construction and commissioning has been proposed according to comparison and analysis of practices in domestic & overseas plant project, procedures for progress control in the globally reputed petrochemical client, company rules and recommendation of the expert in progress control.

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양생기공과 심리기술훈련의 구성요인과 측정평가방법의 비교 연구 (Comparative Study on the Configuration Factors and Measurement Method of Yangsaeng Gigong and Psychological Skills Training)

  • 정미영;한창현;박수진;이상남;권영규
    • 동의생리병리학회지
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    • 제22권5호
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    • pp.1047-1056
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    • 2008
  • If we can evaluate the training results more appropriately and analyze the psychological changes in more objectively, the training can be more efficient and it can help to solve the problems during the training. This research analyzed the similarity and differences of Yangseng Qigong and psychological skill training's components and measurement methods. Also, the research further studied psychological skill training's measurement method. Results : The measurement type of Yangseng Qigong are Sagong, a record of Sagong, Damgong, IIgi, and Sogyeol. Similarly, the measurement type of psychological skills training are questionnaire, interview, personal profile, and observation of a single subject. Despite the similarities between the measurement type of Yangsaeng Qigong and psychological skills training, unfortunately there are differences in the contents. Thus, If we introduce strengths of each method to the other, we may have better measurement methods. The questionnaire method of psychological skills training is the most commonly used method, because it gives concrete, objective, reliable and highly reproducible results. If we refer to the questionnaire development process in psychological skills training, we can have objective and concrete measurement tool for Yangsaeng Qigong training. In the psychological skills training measurement tool development process, there are 5 stages; test conception, test preparation, test execution, question analysis, and test modification. Furthermore, the requirements for the good survey are reliability, validity, practicality, and cultural appropriateness. Through this study, we reached the conclusion that we need to combine two methods together to develop a better method because Yangsaeng Qigong places importance on comprehensive method and realization while psychological skills training places importance on analytical method and objective evaluation. And It seems that a practical study is needed to resolve the concerete problems of Yansaeng Qigong through these concrete cases.

측정불확도를 적용한 차량검지기 속도측정 성능평가방법 개발 (Development of an Performance Evaluation Method for Vehicle Detector Speed Measurement Applying Uncertainty in Measurement)

  • 이환필;김용만;강동윤
    • 한국도로학회논문집
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    • 제14권2호
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    • pp.165-174
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    • 2012
  • 본 연구에서는 차량검지기의 속도측정 성능평가방법을 개발하였다. 개발된 성능평가방법에서는 오차요인들을 기준속도에 반영하며 측정불확도의 개념을 적용하였다. 기존연구, 통계적 처리기법, 기존교통단속장비 및 차량검지시스템의 속도측정 성능평가방법 등에 대한 고찰을 통해 기존평가방법의 문제점을 도출하고 개선된 성능평가방법을 개발하였다, 실제 현장에 설치된 차량검지기에 대해서 기존평가방법과 개발방법을 적용해본 결과 기존평가방법은 평가기준에 적합하나 개발방법은 평가기준을 만족시키지 못하고 있다. 이러한 결과는 기존성능평가방법이 측정 시의 오차요인들을 충분히 고려하지 못해서 평가대상장비의 성능을 고평가할 가능성이 있음을 의미하며, 반면에 개발모형은 측정 시의 변동요인인 오차를 고려하므로 기존평가방법 보다 정확함을 나타낸다.

Antenna Measurement on Cylindrical Surface in Fresnel Region Using Direct Far-Field Measurement System

  • Oh, Soon-Soo;Kim, Joung-Myoun;Yun, Jae-Hoon
    • ETRI Journal
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    • 제29권2호
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    • pp.135-142
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    • 2007
  • The small anechoic chambers built by many small-/medium-sized companies and universities present difficulties in testing electrically large antennas because the chamber size cannot satisfy the far-field criterion of large antennas. In this paper, a method for Fresnel-region measurement on a cylindrical surface with variation of the measurement height is proposed and verified by both calculations and experiments. We implement the proposed method using a direct far-field measurement system by adding a few supporting structures. The results show good accuracy.

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접지된 Shield Plate를 이용한 집적회로의 배선용량 측정 (Direct Measurement of the VLSI Interconnection Line Capacitances Using a Grounded Shield Plate)

  • 강래구;전성오;신윤승
    • 대한전자공학회논문지
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    • 제25권3호
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    • pp.302-307
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    • 1988
  • A noble interconnection line capacitance measurement method to be able to remove the measurement errors from the probe pad to substrate stray capacitance has been proposed and verified. The measurement errors in the capacitance measurement, which usually be involved from the probe pad to substrate stray capacitance, can easily be removed by isolating the metal probe pad from the substrate with a grounded shield plate between the probe pad the substrate. The measurement results by using this improved capacitance measurement method were compared with the calculations by two-dimensional computer simulations.

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Methods to Measure the Critical Dimension of the Bottoms of Through-Silicon Vias Using White-Light Scanning Interferometry

  • Hyun, Changhong;Kim, Seongryong;Pahk, Heuijae
    • Journal of the Optical Society of Korea
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    • 제18권5호
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    • pp.531-537
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    • 2014
  • Through-silicon vias (TSVs) are fine, deep holes fabricated for connecting vertically stacked wafers during three-dimensional packaging of semiconductors. Measurement of the TSV geometry is very important because TSVs that are not manufactured as designed can cause many problems, and measuring the critical dimension (CD) of TSVs becomes more and more important, along with depth measurement. Applying white-light scanning interferometry to TSV measurement, especially the bottom CD measurement, is difficult due to the attenuation of light around the edge of the bottom of the hole when using a low numerical aperture. In this paper we propose and demonstrate four bottom CD measurement methods for TSVs: the cross section method, profile analysis method, tomographic image analysis method, and the two-dimensional Gaussian fitting method. To verify and demonstrate these methods, a practical TSV sample with a high aspect ratio of 11.2 is prepared and tested. The results from the proposed measurement methods using white-light scanning interferometry are compared to results from scanning electron microscope (SEM) measurements. The accuracy is highest for the cross section method, with an error of 3.5%, while a relative repeatability of 3.2% is achieved by the two-dimensional Gaussian fitting method.

Measurement of local wall temperature and heat flux using the two-thermocouple method for a heat transfer tube

  • Ahn, Taehwan;Kang, Jinhoon;Jeong, Jae Jun;Yun, Byongjo
    • Nuclear Engineering and Technology
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    • 제51권7호
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    • pp.1853-1859
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    • 2019
  • The two-thermocouple method was investigated experimentally to evaluate its accuracy for the measurement of local wall temperature and heat flux on a heat transfer tube with an electric heater rod installed in an annulus channel. This work revealed that a thermocouple flush-mounted in a surface groove serves as a good reference method for the accurate measurement of the wall temperature, whereas two thermocouples installed at different depths in the tube wall yield large bias errors in the calculation of local heat flux and wall temperature. These errors result from conductive and convective changes due to the fin effect of the thermocouple sheath. To eliminate the bias errors, we proposed a calibration method based on both the local heat flux and Reynolds number of the cooling water. The calibration method was validated with the measurement of local heat flux and wall temperature against experimental data obtained for single-phase convection and two-phase condensation flows inside the tube. In the manuscript, Section 1 introduces the importance of local heat flux and wall temperature measurement, Section 2 explains the experimental setup, and Section 3 provides the measured data, causes of measurement errors, and the developed calibration method.

콘크리트 압축강도 측정법과 공시체 내 철근이 압축강도 측정에 미치는 실험적 연구 (An Experimental Study on the Compressive Strength of Reinforcing Bars in Concrete Specimens and Compressive Strength Measurement Methods)

  • 이원홍;최상기;이승열;안진희;강범주
    • 한국구조물진단유지관리공학회 논문집
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    • 제25권6호
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    • pp.33-40
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    • 2021
  • 콘크리트 구조물의 안전성 검토에서 콘크리트 압축강도 측정은 매우 중요한 요소이다. 콘크리트 압축강도 측정법에는 파괴방법과 비파괴방법이 있다. 파괴방법은 일축압축파괴방법이 있으며, 비파괴방법에는 반발경도법과 탄성파 측정법이 있다. 본 연구에는 측정법의 종류와 콘크리트 내부의 철근영향에 따른 콘크리트의의 압축강도 영향을 분석하였다. 공시체의 종류와 상관없이 3가지 실험 방법 중 탄성파 측정법에 의한 평균 압축강도가 다른 방법에 의한 평균 압축강도보다 크게 나타났다. 공시체 종류가 같을 경우 탄성파 측정법이 다른 측정법들에 비해 측정값들의 표준편차가 작게 나타났으므로 탄성파 측정법이 다른 두 측정법에 비해 측정값의 변동이 크지 않음을 알 수 있다. 각 공시체별 실험 방법에 따른 평균압축강도를 압축파괴 실험법의 평균압축 강도를 기준으로 비교하면 탄성파 측정법, 압축파괴실험, 반발경도법 순으로 평균압축강도가 높게 측정되었다. 콘크리트의 압축강도 측정방법과 콘크리트 내부 철근 유무에 따라 콘크리트 압축강도 측정값이 상이하므로 추후 피복두께의 영향 등을 고려한 연구가 필요할 것이다.

Uncertainty Assessment using Monte Carlo Simulation in Net Thrust Measurement at AETF

  • Lee, Bo-Hwa;Lee, Kyung-Jae;Yang, In-Young;Yang, Soo-Seok;Lee, Dae-Sung
    • International Journal of Aeronautical and Space Sciences
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    • 제8권2호
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    • pp.126-131
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    • 2007
  • In this paper, Monte Carlo Simulation (MCS) method was used as an uncertainty assessment tool for air flow, net thrust measurement. Uuncertainty sources of the net thrust measurement were analyzed, and the probability distribution characteristics of each source were discussed. Detailed MCS methodology was described including the effect of the number of simulation. Compared to the conventional sensitivity coefficient method, the MCS method has advantage in the uncertainty assessment. The MCS is comparatively simple, convenient and accurate, especially for complex or nonlinear measurement modeling equations. The uncertainty assessment result by MCS was compared with that of the conventional sensitivity coefficient method, and each method gave different result. The uncertainties in the net thrust measurement by the MCS and the conventional sensitivity coefficient method were 0.906% and 1.209%, respectively. It was concluded that the first order Taylor expansion in the conventional sensitivity coefficient method and the nonlinearity of model equation caused the difference. It was noted that the uncertainty assessment method should be selected carefully according to the mathematical characteristics of the model equation of the measurement.

A numerical method for improving the reliability of knee translation measurement in skin marker-based motion analysis

  • Wang, Hongsheng;Zheng, Nigel
    • Advances in biomechanics and applications
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    • 제1권4호
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    • pp.269-277
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    • 2014
  • In skin-marker based motion analysis, knee translation measurement is highly dependent on a pre-selected reference point (functional center) on each segment determined by the location of anatomical landmarks. However, the placement of skin markers on palpable anatomical landmarks (i.e., femoral epicondyles) has limited reproducibility. Thus, it produces large variances in knee translation measurement among different subjects, as well as across studies. In order improve the repeatability of knee translation measurement, in this study an optimization method was introduced, by which the femoral functional center was numerically determined. At that point the knee anteroposterior translation during the stance phase of walking was minimized. This new method was tested on 30 healthy subjects during walking in gait lab with motion capture system. Using this new method, the impact of skin marker position (at anatomical landmarks) on the knee translation measurement has been minimized. In addition, the ranges of anteroposterior knee translations during stance phase were significantly (p<0.001) smaller than those measured by conventional method which relies on a pre-selected functional center ($11.1{\pm}3.5mm$ vs. $19.9{\pm}5.5mm$). The results of anteroposterior translation using this new method were very close to a previously reported knee translation (12.4 mm) from dual fluoroscopic imaging technique. Moreover, this new method increased the reproducibility of knee translation measurement by 50%.