• Title/Summary/Keyword: Method of Measurement

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An Integrated Approach to Measuring Supply Chain Performance

  • Theeranuphattana, Adisak;Tang, John C.S.;Khang, Do Ba
    • Industrial Engineering and Management Systems
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    • v.11 no.1
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    • pp.54-69
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    • 2012
  • Chan and Qi (SCM 8/3 (2003) 209) developed an innovative measurement method that aggregates performance measures in a supply chain into an overall performance index. The method is useful and makes a significant contribution to supply chain management. Nevertheless, it can be cumbersome in computation due to its highly complex algorithmic fuzzy model. In aggregating the performance information, weights used by Chan and Qi-which aim to address the imprecision of human judgments-are incompatible with weights in additive models. Furthermore, the default assumption of linearity of its scoring procedure could lead to an inaccurate assessment of the overall performance. This paper addresses these limitations by developing an alternative measurement that takes care of the above. This research integrates three different approaches to multiple criteria decision analysis (MCDA)-the multiattribute value theory (MAVT), the swing weighting method and the eigenvector procedure-to develop a comprehensive assessment of supply chain performance. One case study is presented to demonstrate the measurement of the proposed method. The performance model used in the case study relies on the Supply Chain Operations Reference (SCOR) model level 1. With this measurement method, supply chain managers can easily benchmark the performance of the whole system, and then analyze the effectiveness and efficiency of the supply chain.

Evaluation of Measurement Precisions Using Approximate F Tests and EMS in the Gauge R&R Studies (게이지 R&R 연구에서 근사 F검정과 EMS를 이용한 측정 정밀도의 평가)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.11 no.3
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    • pp.209-216
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    • 2009
  • A development in method of evaluating the measurement precisions using approximate F tests and variance components from expected mean square (EMS) is investigated. The research proposes three-factor mixed measurement models with the fixed and random factors. Unrestricted and unconstrained design work was rarely studied, while restricted and constrained designs have been significantly discussed. The unrestricted and unconstrained designs assume to be an independence of interaction. The proposed evaluation method about the measurement precisions can be extended to four-factor random measurement model or mixed measurement model. The study also presents the three evaluation indexes of precisions such as R&RTR (Reproducibility & Repeatability-To-Total Precision Ratio), PTR (Precision-To-Tolerance Ratio), and SNR (Signal-To-Noise Ratio). Numerical examples are proposed to evaluate the approximate F tests with Satterthwaite degrees of freedom and three indexes using the measurement precisions from EMS.

A Comparative Study for Odor Control Regulations (악취관리제도의 국가간 비교연구)

  • 양성봉;김석만
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.1
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    • pp.79-87
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    • 2000
  • This study analyzed the regulations concerning odor management or control in Korea, Japan, and developed countries such as USA and Germany. The Korean restriction standards and measurement methods for offensive odor substances are very similar to the Japanese standards and methods promulgated in 1976. Japan promulgated the odor control act and the specific measurement methods of the offensive odor substances in 1973. In Japan, currently, the local governments can establish their own odor restriction areas and proclaim their own standards suitable for their situations. Also, Japan has more strict regulations and more offensive odor substances to be monitored than Korea. The restriction standards of odor in German is quite similar to the permissible limits and standards of air pollutants at emission sources in Korea. Many states in USA are adopting their own restriction standards and measurement methods, e.q., the ambient air pollution standards, organic functionstest methods by dilation, and establishment and addition of air pollution control equipment at emission sources. Finally, this study analyzed the problems of the regulations, standards, and measurement methods concerning the Korean offensive odor management. Since the direct organic fuctions measurement(DOFMM) method is depending upon the personal sensitives of odor substances, the measurement odor value can be equivocal. That is, the odor measurement value by an examines can differ from that by the other examines. Also, there can be conflicts with the measured odor values depending upon the applied measurement methods, e.q., the DOFMM, the dilation method, and the instrumental analysis method.

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Development of Size Measurement and Inspection Algorithm for Autoclaves Lightweight Concrete Block by Image Processing (영상처리에 의한 경량기포 콘크리트 블록의 치수측정 및 불량경사 알고리즘 개발)

  • 김성훈;허경무
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.40 no.4
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    • pp.206-213
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    • 2003
  • In this paper, we propose a design method of automatic thickness measurement and defect inspection system, which measures the thickness of the autoclaved lightweight concrete block and inspects the defect on a real-time basis. The image processing system was established with a CCD camera, an image grabber, and a personal computer without using assembled measurement equipment. For the realization of proposed algorithm, the preprocessing method that can be applied to overcome uneven lighting environment, threshold decision method, unit length decision method in uneven condition with rocking objects, and the curvature calibration method of camera using a constructed grid are developed. From the experimental results, we have found that the required measurement accuracy specification is sufficiently satisfied using our proposed method.

Reduction of Minimum Switching Duration in the Measurement of Three Phase Current with DC-Link Current Sensor (DC링크 전류센서를 이용한 삼상전류 측정 방식에서 최소 스위칭 시간의 단축)

  • 김경서
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.52 no.12
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    • pp.649-654
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    • 2003
  • The simplest method for measuring output currents of the three phase inverters is to measure them with three current sensors such as hall sensors. This method requires at least two current sensors, and these types of sensors are somewhat expensive. More economical method is measuring DC link current with a simple shunt resistor, then, reconstructing output current using the DC link current value and the switching status. However, in low speed region, the measurement becomes difficult and even impossible due to the requirement of minimum switching duration for A/D conversion. These problems can be overcome by limitation of switching duration. Limitation of switching, however, causes voltage and current distortion. Owing to compensation, distortion can be effectively suppressed. However these increase acoustic noise due to increment of current ripple. In this paper, a current measurement method is proposed, which can reduce minimum switching duration resulting in reduction of acoustic noise. The validity of proposed method is confirmed through experiment.

The calculation and Measurement Methods for G/T of the Telemetry Small Aperture Antenna (원격자료수신장비 소형반사판 안테나 G/T 예측 및 측정)

  • Kim, Chun-Won;An, Na-Gyun;Kim, Dong-Hyun;Cho, Byung-Lok
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.9
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    • pp.657-662
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    • 2022
  • In this paper, the calculation using simulation and two measurement methods for G/T of the telemetry are analyzed. Antenna gain and noise temperature are calculated by using ICARA and Antenna Noise Temperature Calculator. System G/T were calculated by using Antenna gain/noise temperature, LNA gain/noise temperature, cable loss. The first G/T measurement method is Y-factor measurement method, which is to calculate G/T by comparing LNA noise temperature and a signal level difference when an antenna and a 50ohm termination are respectively connected to an LNA input terminal Second method is Solar calibration measurement method that is to calculate G/T by comparing noise level difference when looking at the sun and lowest level point. Finally, the accuracy was reviewed by comparing the G/T calculation results with the two measurement methods, and the optimal measurement method according to antenna performance and operating environment was presented.

Development of automatic measurement method of concentricity and roundness using image processing technique

  • Moon, Hyung-Wook;Huh, Kyung-Moo
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.130.2-130
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    • 2001
  • In this paper, we suggest an algorithm for the automatic measurement of concentricity and roundness using image processing technique. From the experimental results, we could find that the required measurement accuracy specification is sufficiently satisfied using our proposed method.

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Development of Fuel Economy Measurement Method for Hydrogen Fuel Cell Vehicles (수소연료전지자동차 연료소비율 측정방법에 대한 연구)

  • Lim, Jong-Soon;Choi, Young-Tae;Yong, Gee-Joong;Kwon, Hae-Boung;Lee, Hyun-Woo;Maeng, Jeong-Yoel
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.636-639
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    • 2009
  • Fuel consumption measurement of Hydrogen fuel cell vehicle is considerably different form internal combustion engine vehicle such as carbon balance method. A practical method of fuel Consumption measurement has been developed for Hydrogen fuel cell vehicles. There are three method of hydrogen fuel consumption testing, gravimetric, PVT(Pressure, Volume and temperature), and Coriolis mass flow, all of which necessitate physical measurements of the fuel supply. The purpose of this research is to measure the fuel consumption of hydrogen fuel cell vehicles on chassis-dynamometer and to give information when the research is intended to develop method to measure hydrogen fuel consumption.

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The Educational Significance of the Method of Teaching Natural and Fractional Numbers by Measurement of Quantity (양의 측정을 통한 자연수와 분수 지도의 교수학적 의의)

  • 강흥규;고정화
    • School Mathematics
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    • v.5 no.3
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    • pp.385-399
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    • 2003
  • In our present elementary mathematics curriculum, natural numbers are taught by using the a method of one-to-one correspondence or counting operation which are not related to measurement, and fractional numbers are taught by using a method which is partially related to measurement. The most serious limitation of these teaching methods is that natural numbers and fractional numbers are separated. To overcome this limitation, Dewey and Davydov insisted that the natural number and the fractional number should be taught by measurement of quantity. In this article, we suggested a method of teaching the natural number and the fractional number by measurement of quantity based on the claims of Dewey and Davydov, and compare it with our current method. In conclusion, we drew some educational implications of teaching the natural number and the fractional number by measurement of quantity as follows. First, the concepts of the natural number and the fractional number evolve from measurement of quantity. Second, the process of transition from the natural number to the fractional number became to continuous. Third, the natural number, the fractional number, and their lower categories are closely related.

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A New Velocity Measurement Method using Linear Type Hall-effect Sensor for Electro-mechanical Fin Actuator (선형홀센서를 이용한 전기식 구동장치의 속도 신호 구현)

  • Gu, Jeong-Hoi;Song, Chi-Young
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.1
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    • pp.70-75
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    • 2010
  • The objective of this paper is to propose a new velocity measurement method for an electro-mechanical fin actuator. The model of the electro-mechanical fin actuator includes uncertainties such as unknown disturbances and parameter variations in flight condition. So, an electro-mechanical fin actuator system needs robust control algorithm which requires not only position information but also velocity information. Usually, analog tachometers have been used for velocity feedback in an electro-mechanical fin actuator. However, using these types of sensors have problems such as the cost, space, and malfunction. These problems lead to propose a new velocity measurement method using linear type Hall-effect sensor. In order to verify the proposed method, several experiments are performed using Model Following Sliding Mode Controller(MFSMC). It is shown that the MFSMC with a new velocity measurement method using linear type Hall-effect sensor can satisfy the requirements without using of velocity sensor.