• Title/Summary/Keyword: measurement method

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

  • Cho, Hong-Yeon;Yoo, Hoseon
    • Plant Journal
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    • v.7 no.4
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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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Comparative Study on the Configuration Factors and Measurement Method of Yangsaeng Gigong and Psychological Skills Training (양생기공과 심리기술훈련의 구성요인과 측정평가방법의 비교 연구)

  • Jung, Mi-Young;Han, Chang-Hyun;Park, Soo-Jin;Lee, Sang-Nam;Kwon, Young-Kyu
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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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.

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

  • Lee, Hwan-Pil;Kim, Yong-Man;Kang, Dong-Yun
    • International Journal of Highway Engineering
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    • v.14 no.2
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    • pp.165-174
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    • 2012
  • In this study, a method for evaluating the performance of speed measurements was developed to assess the qualities of a vehicle detector. The evaluation method considers measurement errors that are reflected in a reference speed. For this, the concept of uncertainty in measurement was applied to the development method. Other factors such as precedent study, statistical processing techniques, and speed measurement performance method of traffic enforcement equipment and vehicle detection systems were also reviewed. Through this process, the problems of the existing evaluation methods were derived and developed for the new performance evaluation method. Vehicle detectors that are installed in the field were evaluated using the traditional assessment methods and the developed method. As a result, for traditional assessment methods, it was found that evaluation criteria are acceptable, while developed method's criteria are not acceptable. This means that traditional assessment methods do not sufficiently consider errors in measurement, so it has potential to over-estimate for performance of evaluation equipment. On the other hand, it was represented that the developed method should include variable factor such as errors in measurement and more precise compared to traditional assessment methods.

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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    • v.29 no.2
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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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Direct Measurement of the VLSI Interconnection Line Capacitances Using a Grounded Shield Plate (접지된 Shield Plate를 이용한 집적회로의 배선용량 측정)

  • 강래구;전성오;신윤승
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.3
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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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    • v.18 no.5
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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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    • v.51 no.7
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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.

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

  • Lee, Won-Hong;Choi, Sang-Gi;Lee, Seuong-Yeol;Ahn, Jin-Hee;Kang, Beom-Ju
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.6
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    • pp.33-40
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    • 2021
  • Measuring the compressive strength of concrete is a very important factor in the safety review of concrete structures. Concrete compressive strength measurement methods include destructive and non-destructive methods. The destructive method includes the uniaxial compression failure method, and the non-destructive method includes the rebound hardness method and the elastic wave measurement method. In this study, the type of measurement method and the effect of reinforcing bars inside the concrete were tested to examine the relationship between them. Regardless of the type of specimen, the average compressive strength by the elastic wave measurement method among the three experimental methods was greater than the average compressive strength by the other methods. When the specimen type is the same, the standard deviation of the measured values of the elastic wave measurement method is smaller than that of the other measurement methods, so it can be seen that the elastic wave measurement method does not show large variance in the measured values compared to the other two measurement methods. When the average compressive strength according to the test method for each specimen was compared with the average compressive strength of the compressive failure test method, the average compressive strength was measured to be high in the order of the elastic wave measurement method, the compression failure test, and the rebound hardness method. Since the measured values of the compressive strength of concrete are different depending on the method of measuring the compressive strength of concrete and the presence or absence of reinforcing bars inside the concrete, further research is required considering the effect of various concrete covers.

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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    • v.8 no.2
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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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    • v.1 no.4
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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%.