• Title/Summary/Keyword: 측정(measurement)

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A Study on the Modeling and Propagation to Evaluate Uncertainties in Measurement Results (측정결과의 불확도산정을 위한 모델링과 불확도 전파에 관한 연구)

  • 김종상;조남호
    • Journal of the Korea Society of Computer and Information
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    • v.8 no.4
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    • pp.165-175
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    • 2003
  • The concept of measurement uncertainty has been recognised for many years since "Guide to the Expression of Uncertainty in Measurement" was published 1993 by ISO. This study firstly propose the mathematical model to evaluate uncertainty considering the dispersion of samples because the mathematical model of a measurement is an important to evaluate uncertainty, and it must contains every quantify which contribute significantly to uncertainty in the measurement result. Secondly the standard uncertainty of the result of a measurement, namely combined standard uncertainty is evaluated using the law of propagation of uncertainty, what is termed in GUM method. In GUM method, a measurand is usually approximated by a linear function of its variables by the transforming its input quantities. Furthermore central limit theorem is applied to the input quantity. However the mathematical model of a measurement is generally not always a linearity function, and a distribution function of input or output quantity is not necessarily normal distribution. Then, in some cases GUM method is not favorable to evaluate a measurement uncertainty. Therefore this study propose a new method and its algorithm which use the Monte-carlo simulation to evaluate a measurement uncertainty in both case of linearity or non-linearity function. function.

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A comparative analysis of measurement domain of elementary school mathematics curriculum in Korea and Japan: centered on extensive quantity (우리나라와 일본의 초등학교 수학과 교육과정 측정 영역 비교·분석: 외연량을 중심으로)

  • Lee, Seung Eun;Lee, Jeong Eun;Park, Kyo Sik
    • Journal of the Korean School Mathematics Society
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    • v.21 no.1
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    • pp.19-37
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    • 2018
  • In this study, the actual state of teaching seven extensive quantities (time, length, capacity, weight, area, angle measure, volume) of measurement domain are analyzed comparatively between the 2015 revised elementary school mathematics curriculum in Korea and the 2017 revised elementary school mathematics curriculum in Japan in terms of comparison in measurement, direct measurement, indirect measurement, and estimation in measurement. From the results of this comparative analysis, some implications for discussion on the development of the next elementary school mathematics textbook and the next elementary mathematics curriculum can be suggested. First, it is necessary to discuss on clarifying the range of handling of comparison, direct measurement, indirect measurement, estimation of seven extensive quantities respectively. Second, it is necessary to discuss on doing direct comparison when intuitive comparison is difficult. Third, it is necessary to discuss on reconsidering indirect comparison of weights. Fourth, it is necessary to discuss on reconsidering measurement using arbitrary units in case of angular measures. Fifth, it is necessary to discuss on dealing with estimating the area of $1cm^2$ and $1m^2$ and the volume of $1cm^3$ and $1m^3$ for the purpose to make rough guesses their size respectively.

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.

Study on the 3D Assembly Inspection of Two-Step Variable Valve Lift Modules Using Laser-Vision Technology (레이저 비전을 이용한 2단 가변밸브 리프트 모듈의 3D 조립검사에 대한 연구)

  • Nguyen, Huu-Cuong;Kim, Do-Joong;Lee, Byung-Ryong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.10
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    • pp.949-957
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    • 2017
  • A laser-vision-based height measurement system is developed and implemented for the inspection of two-step variable valve lift module assemblies. The proposed laser-vision sensor module is designed based on the principle of laser triangulation. This paper summarizes the work on 3D point cloud data collection and height difference measurements. The configuration of the measurement system and the proposed height measurement algorithm are described and analyzed in detail. Additional measurement experiments on the height differences of valves and lash adjusters of a two-step variable valve lift module were implemented repeatedly to evaluate the accuracy and repeatability of the proposed measurement system. Experimental results show that the proposed laser-vision-based height measurement system achieves high accuracy, repeatability, and stabilization for the inspection of two-step variable valve lift module assemblies.

Cost Measurement Indicators and Maintenance Cost Estimation Model for Maintenance of Component-based Software (컴포넌트 소프트웨어의 유지보수를 위한 비용 측정지표 및 비용 추정 모델)

  • Jo, Ju-Yeon;Rhew, Sung-Yul
    • The KIPS Transactions:PartD
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    • v.16D no.3
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    • pp.353-360
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    • 2009
  • Most information systems are component-based and developed by outsourcing, and developed software is maintained integrative. However, studies on cost measurement indicators and cost estimation model have not been performed sufficiently, which are foundational to enhance the productivity and efficiency of maintenance. This study suggests indicators to measure maintenance cost for component-based software and examines maintenance cost estimation model of component software by the measurement indicators suggested. In order to generate the indicators to measure the component-based maintenance cost, the previously proposed indicators are summarized comparatively. To estimate the measurement indicators of component-based software, it makes a comparison of the previously proposed indicators and arranges them. We classify the measurement indicators by how to apply according to maintenance types of component software and then we propose the cost measurement indicators. Moreover, we propose the cost estimation model according to the maintenance types of component software using the suggested measurement indicators suggested. With the suggested estimation model, a case study is performed and its validity is verified.

An Approach to Measure Anthropometric Data of Simulated Human Hand Using Photogrammetry (시뮬레이션 환경에서 사진측량기법을 이용한 손 치수 측정 방법에 대한 연구)

  • Chang, Ji Hong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.5
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    • pp.511-517
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    • 2016
  • Anthropometric data of the hand is one of the important issues for the product design related with hand and manual operation in terms of user-centered design. Direct measurement, which traditionally uses anthropometric measuring tool, has a few disadvantages in cumulation of measuring time, possible errors in raw data, doubtful reliability between inspectors. Newly introduced 3D scanning technology overcomes those disadvantages; however, another disadvantages, such as, hight cost and immovability, have been introduced. In this study, photogrammetric approach was introduced for the measurement of anthropometric data in hand. In order to minimize the possibility of error during direct and indirect measurement, a simulated object was used and effectiveness of photogrametric measurement was confirmed for the collection of anthropometric data in hand.

Development of Profilometry based on a Curvature Measurement (곡률에 근거한 형상 측정기술 개발)

  • Kim, Byoung-Chang
    • Korean Journal of Optics and Photonics
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    • v.18 no.2
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    • pp.130-134
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    • 2007
  • I present a novel curvature profilometer devised fur the profile measurement of aspheric and free-form surfaces on the nanometer scale. A profile is reconstructed from measuring the curvature of a test part of the surface at several locations along a line. For profile measurement of free-farm surfaces, methods based on local part curvature sensing have strong appeal. Unlike full-aperture interferometry they do not require customized null optics. The measurement accuracy of the curvature profilometer was assessed by comparison with a well-calibrated interferometer in NIST. Experimental results prove that the maximum discrepancy turns out to be 37 nm on the 28 mm measurement range for the spherical mirror.

Ratio-type Capacitance Measurement Circuit for femto-Farad Resolution (펨토 패럿 측정을 위한 비율형 커패시턴스 측정 회로)

  • Chung, Jae-Woong;Chung, In-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.5
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    • pp.989-998
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    • 2012
  • A ratio type of capacitance measurement circuit is proposed to measure an extremely small value of the fF capacitance on this paper. This measurement circuit is formed with a switched-capacitor integrator, a comparator, and logic circuit blocks to control the switches. It converts the measured ratio value between the known value of on-chip capacitor and the unknown value of capacitor to the digital signal. The fF capacitance with minimized error can be obtained by calculating this ratio. This proposed circuit is designed with standard CMOS $0.18{\mu}m$ process, and various HSpice simulations prove that this capacitance measurement circuit is able to measure the capacitance under 5fF with less than ${\pm}0.3%$ error rate.

Design of KPI on Individual Performance Measurement System (개별성과측정시스템의 주요성과지표 설계 연구)

  • Hong, Hyun-Gi;Oh, Sang-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.9 no.3
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    • pp.815-821
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    • 2008
  • Performance of corporation results from operation of tangible and intangible assets. Thus, measuring performance need to be taken place in terms of tangible and intangible aspects. However, the research objects, in the measurement of performance, do not guarantee researchers to achieve quantitative results and it is difficult to have objectivity. There are also many different points between a big enterprise and a small-medium size company. These facts require new measurement methods. This study suggests aspects of measurement method as task, attitude, ability and qualification for small-medium size companies. Specially, this study suggest individual measurement method than organizational one. The research system consists of users, team leaders and staffs charge of BSC and the users can access BSC sewer to input, to evaluate and to prove data through their own accounts.

A Study on Improvement through Analysis of Problem on Physical Activity Promotion System(PAPS) (학생건강체력시스템(PAPS)의 문제점 분석과 개선방안에 대한 연구)

  • Park, Hyoung-Kil
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.7
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    • pp.87-96
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    • 2021
  • The purpose of this study is to analyze the problems of the Physical Activity Promotion System(PAPS) implemented in elementary, middle, and high schools in Korea and to prepare improvement measures. The data of the study was obtained through in-depth interviews, related papers, and press releases. The research participants of this study were 5 incumbent physical education teachers who directly instruct and measure PAPS at school and 5 college students who directly experienced PAPS. The results of the study are as follows. First, the problems that occurred in the educational environment of PAPS were students' indifference, teachers' passive guidance, and decreased physical education hours replaced by PAPS measurement days. Second, the problems occurring in the measurement environment of PAPS were errors due to measurement equipment, deviations due to different measurement locations, and differences in grades according to measurement items. Third, the problems that occur in the measurement process of PAPS are the lack of measurement personnel, the expedient physical fitness measurement, and the non-standardized measurement method. In order to improve these problems and successfully apply PAPS, the following improvement measures should be attempted. Details on this are as follows. First, teachers should inspire students' interest and interest in PAPS. Second, it is necessary to secure the reliability of the measurement result value of PAPS. Third, it is necessary to systematically supplement the school education system for PAPS measurement.