• Title/Summary/Keyword: Standard measure

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Evaluation methodology of assemblability for the small-sized product (소형 제품의 조립용이성 평가 방법론)

  • Mok Hak Soo;Cho Jong Rae;Kang Young Hun
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2002.05a
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    • pp.616-623
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    • 2002
  • This paper proposes a new DFA methodology that ran estimate the standard assembly time and evaluate the assemblability of parts for small-sized product. We deride some determining and influencing factors related with assembly process and measure the assembly time using notion analysis to estimate of assemblability. We deduce quantitative store of assemblability through analysis of a correlation between determining factors and grade of influencing factors.

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Measurement of the pressure between elastic bodies and between an elastic and a rigid body using elastic-body pressure meter (연체압측정기를 이용한 연체 사이의 압력 측정)

  • 김운회;박경수
    • Journal of the Ergonomics Society of Korea
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    • v.8 no.2
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    • pp.43-47
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    • 1989
  • An instrumentation system to measure the pressure between elastic bodies and between an elastic and a rigid body has been developed. The force between elastic bodies can be measured only by Elastric- body pressure Meter. As a standard Elastic-body pressure Meter, Model RCG-24A consists of 24 pick-ups, one switch box and one amplifier and measuring is possible at each of 24 measuring spots by swithing one to the nest using the switch box. The system can be used in various specialized disciplines, such as ergonomics, anthropometry and biomechanics.

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A Study on the Electric Railroad Grounding System of Tunnels and Bridges (전기철도 시스템에서의 터널, 교량구간 접지방안 연구)

  • 윤응규;오광해;오기봉
    • Proceedings of the KSR Conference
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    • 2002.10a
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    • pp.559-565
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    • 2002
  • This paper presents a standard grounding scheme for bridge and tunnel areas where earthing wires cannot be easily buried. Specially, a new grounding method in which structure grounding devices are used shows good grounding effects like the earthing-wire grounding scheme. The proposed method can be a measure for equal potential in case earthing cables are disconnected.

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Statistical Discriminant Analysis on the Driving Ability of the Brain-injured

  • Kim, Jae-Hee;Kim, Jeong-A
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.1
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    • pp.19-31
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    • 2005
  • Brain injured patients who had the driver's license before the injury of the brain were tested with the newly developed tool CPAD by Hangyang Medical School and the National Rehabilitation Center. The CPAD contains many variables to measure the ability of driving. Also for each patient the American standard CBDI score was measured and the result was compared with the CPAD results. Of interest is to classify the patients as pass, border, fail group after the CPAD test. To derive the discriminant functions with the group information based on CBDI, parametric/nonparametric and multivariate/univariate discriminant analysis was performed and discussed.

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A Comparative Study on the Evaluation of Process Capability for Non-Normal Distributions (비정규분포에 대한 공정능력 평가에 관한 비교 연구)

  • 이상용;채규용
    • Journal of Korea Society of Industrial Information Systems
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    • v.5 no.3
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    • pp.77-86
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    • 2000
  • The main objectives of this dissertation is to propose a forth generation index C for the case where the target value T is not equal to the midpoint of the specification limits (i.e. asymmetric tolerances), and show that this index is more sensitive compared to the standard PCI's in detacting small shifts of the process mean from the target value. In conclusion, in this dissertation , a new methods for estimating a measure of process capability for non-normally distributed variable data is proposed using the percentage nonconforming.

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Development of Automated Non-contact Thickness Measurement Machine using a Laser Sensor (레이저센서를 이용한 비접촉식 두께자동측정기 개발)

  • Cho, Kyung-Chul;Kim, Soo-Youn;Shin, Ki-Yeol
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.14 no.2
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    • pp.51-58
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    • 2015
  • In this study, we developed an automated non-contact thickness measurement machine that continuously and precisely measures the thickness and warp of a PCB product using a laser sensor. The system contains a measurement part to measure the thickness in real time automatically according to the set conditions with an alignment supply unit and unloading unit to separate OK and NG products. The measurement machine was utilized to evaluate the performance at each step to minimize measurement error. At the zero setting for the initial setup, the standard deviation of the 216 samples was determined to be $5.52{\mu}m$. A measurement error of 0.5mm and 1.0mm as a standard sample in the measurement accuracy assessment was found to be 2.48% and 2.28%, respectively. In the factory acceptance test, the standard deviation of 1.461mm PCB was measured as $28.99{\mu}m$, with a $C_{pk}$ of 1.2. The automatic thickness measurement machine developed in this study can contribute to productivity and quality improvement in the mass production process.

A Study on the Improvement of Validation and Application for Slipmeters using Reference Surfaces (표준 바닥재를 이용한 미끄럼 측정기의 검증방법 개선 및 활용방안)

  • Kim, Jung-Soo
    • Journal of the Korean Society of Safety
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    • v.28 no.6
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    • pp.73-78
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    • 2013
  • The purpose of this study was to evaluate three kinds of slipmeters (BOT, BPT, English XL) used on-site floor with ASTM F2508 which is comprised of four different standard surfaces(polished granite, glazed porcelain, vinyl composite tile ;VCT, and ceramic tile). ASTM F2508 has two criteria that decide which slipmeter is appropriate or not. The evaluated slipmeters were dreg sled, articulated sturt, and pendulum strike type. The test results revealed that two kinds of slipmeters(BOT, BPT) successfully ranked all four standard surfaces and differentiated among standard surfaces with varying degrees of slipperiness. Nevertheless, the measured value with BOT on the VCT, which was reported as slippery floor in previous study, was higher than its threshold(0.6). Although some slipmeter satisfy two criteria of ASTM F2508, they can underestimate the slip potential. So, another criteria is needed so as to reduce this problem. English XL couldn't properly measure slipperiness under the two kind of floors(glazed porcelain, VCT). So the slider of English XL was modified in order to meet two criteria of ASTM F2508.

Development of Surface Acoustic Wave Sensor for Viscosity Measurement of Low Viscose Liquid Using Love Wave (Love파를 이용한 저점성 유체 점도 측정용 표면 탄성파 센서 개발)

  • Lee, Sang-Dae;Kim, Ki-Bok;Lee, Dae-Su
    • Journal of Biosystems Engineering
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    • v.33 no.4
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    • pp.282-287
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    • 2008
  • Love wave is one of the shear horizontal waves and it can propagate between two layers in liquid without energy loss. The SAW (surface acoustic wave) sensor using Love wave is very useful for real time measurement of the viscosity of liquid with high sensitivity. In this study, the 77 MHz and 155 MHz Love wave SAW sensors were fabricated and use to measure the viscosity of low viscous liquid. To generate the surface acoustic wave, the inter-digital transducers were fabricated on the quartz crystal wafer. In order to obtain the optimal thickness of the coating film (novolac photoresist) generating the Love wave on the surface of SAW device, theoretical calculation was performed. The performances of fabricated Love wave SAW sensors were tested. As test liquid, pure water and glycerol solutions having different concentrations were used. Since the determination coefficients of the regression equations for measuring the viscosity of liquid are greater than 0.98, the developed Love wave SAW sensors in this study will be very useful for precise measurement of viscosity of liquid.

Study on Standard Framework for Analyzing Government R&D Program: the case of Preliminary Feasibility Study on R&D Program (국가연구개발사업의 사전 분석틀 표준화 연구: 연구개발 부문 예비타당성조사 표준지침을 중심으로)

  • Ahn, Sang-Jin;Kim, Hye-Won;Lee, Yoon Been
    • Journal of Korea Technology Innovation Society
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    • v.16 no.1
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    • pp.176-198
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    • 2013
  • Preliminary feasibility study(PFS) was introduced in 1999 by financial authority to encourage a cautious approach to new large-scale public investment project. As it applied cost-benefit analysis as prime measure for decision-making, various issues have been arisen concerning feasibility analysis on R&D programs. This work is intended to suggest standard approaches to be established in PFS on R&D program as follows: 1. The issue questions can be induced in a standard way by 15 representative questions and their correlation with evaluation criteria. 2. The analyzing strategy can be standardized by establishing standards for classification of R&D effects and R&D logic analysis.

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Comparison of Antenna Parameters of R-/S-Band Standard Gain Horn Antennas

  • Kang, Jin-Seob;Kim, Jeong-Hwan;Park, Jeong-Il
    • Journal of electromagnetic engineering and science
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    • v.15 no.4
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    • pp.224-231
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    • 2015
  • A comparison of the antenna parameters for R-band (1.7-2.6 GHz) and S-band (2.6-3.95 GHz) standard gain horn antennas has been performed by the Korea Research Institute of Standards and Science (KRISS), together with seven domestic participants from private companies and public institutions. Its purpose, as a proficiency test program of the 'Antenna Measurement Club' of KRISS, was to check equivalences in antenna parameter measurements between KRISS and the participants, particularly in the R-/S-band, to support antenna manufacturers and end users in Korea. The measurement parameters of this comparison are the power gain, radiation pattern, and reflection coefficient of the traveling standards for R-/S-band pyramidal standard gain horn antennas. The comparison used a gain comparison method and an extrapolation method to measure the power gain of the two traveling standards; the radiation patterns were measured in the far-field region of the transmitting and receiving antennas.