• Title/Summary/Keyword: Measurement Model Validation

검색결과 245건 처리시간 0.024초

Flow characteristics of axial fan with shroud (축류홴과 슈라우드의 유량 및 내부 유동 특성)

  • Lee, Kwang-Hee;Kim, Jae-Won
    • The KSFM Journal of Fluid Machinery
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    • 제11권5호
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    • pp.30-36
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    • 2008
  • Axial fan without static blades requires the duct as a guidance for unskewed inflows. This work examined the geometric effects of a duct guided the in and out flows through an impeller. The present methodologies are computational predictions with parallel work by experimental validation. Several different positions of a rotor in a duct are proposed for plausible models of a rotor inside a duct. The optimum axial position of an impeller in a duct is found at the #4 model where the impeller lies on the inlet edge of a circular duct. The model shows a wider inlet area. The result of computational prediction is in good agreement with experiment measurement.

High-Frequency Analysis Modeling of Hybrid Vehicle Battery (하이브리드 자동차 배터리의 고주파 해석 모델링)

  • Lee, Jae-Joong;Lee, June-Sang;Kim, Mi-Ro;Kweon, Hyck-Su;Nah, Wan-Soo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • 제61권2호
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    • pp.263-269
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    • 2012
  • In order to present that the electromagnetic compatibility standards following the frequency goes up which is based automotive electronics, in this paper, a hybrid/electric vehicle battery which reflects the frequency of the equivalent circuit model is introduced. By using this circuit modeling, the impedance characteristics can be analysed and an analyze of battery one cell is finished. Using this model, each different from the discharging situation, the discharge characteristic curve could be led. Basic theoretical approaches and measuring results through MATLAB and experimental validation of the EIS measurement equipment was used.

Validation of a Scale for Elementary School Students' Attitudes toward Mathematics (초등학생용 수학에 대한 태도척도의 개발과 타당화)

  • Jung, Hye Young;Lee, Kyeong Hwa
    • Korean Journal of Child Studies
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    • 제27권5호
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    • pp.49-65
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    • 2006
  • This attitudes scale for prediction of mathematics achievement by elementary school students was developed from 50 initial items from the literature rated for content validity by 30 experts. The ratings rendered 31 revised items used for exploratory factor analysis and reliability tests. The 31 items were administered to 183 elementary students in 4th, 5th, and 6th grades, yielding 4 factors : enjoyment, confidence, value, and motivation with high inter-items consistency. To confirm appropriateness of the constructed model and to test its predictability in mathematics achievements, confirmative factor analysis and discriminant analysis were performed on 693 cases. Results showed that the attitude scale model of 4 factors can be recommended for use in the measurement of elementary school students' attitudes toward mathematics.

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Prediction of Tidal Regime According To Garolim Tidal Power Plant operation (가로림만 조력발전소 가동에 따른 조석체계 변화 예측)

  • Kang, Sok-Kuh;Lee, Kwang-Soo;Park, Jin-Soon;Yum, Ki-Dai
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2007년도 춘계학술대회
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    • pp.639-643
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    • 2007
  • Tidal regime change with general hydrolic condition change is examined, according to Garolim Tidal Power Plant (TPP) operation. Numerical model has been developed for the Yellow and East China Seas region, in order to consider the tidal regime change by the TPP operation. The changes of tidal elevation and tidal current inside the Garolim bay are also investigated in details, along with examining the change of the tidal flat area with operation. The field measurement for the tide and current have been carried out for the validation of the numerical model and for understanding the state of current system in the present state.

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Investigation on the Flow Field Characteristics of a Highly Underexpanded Pulsed Plasma Jet

  • Kim, Jong-Uk;Kim, Youn J.
    • Journal of Mechanical Science and Technology
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    • 제15권12호
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    • pp.1691-1698
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    • 2001
  • In recent years, significant progress has been made in modeling turbulence behavior in plasma and its effect on transport. It has also been made in diagnostics for turbulence measurement; however, there is still a large gap between theoretical model and experimental measurements. Visualization of turbulence can improve the connection to theory and validation of the theoretical model. One method to visualize the flow structures in plasma is a laser Schlieren imaging technique. We have recently applied this technique and investigated the characteristics of a highly underexpanded pulsed plasma jet originating from an electrothermal capillary source. Measurements include temporally resolved laser Schlieren imaging of a precursor blast wave. Analysis on the trajectory of the precursor blast wave shows that it does not follow the scaling expected for a strong shock resulting from the instantaneous deposition of energy at a point. However, the shock velocity does scale as the square root of the deposited energy, in accordance with the point deposition approximation.

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Human Auditory Model Design and Quality Assessment (인간 청각 모델의 설계 및 성능 평가)

  • Ryu, Seung-Wan;Kim, Su-Kweor;Park, Jeong-Yeol;Jaeho Shin
    • Proceedings of the IEEK Conference
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    • 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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    • pp.2144-2147
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    • 2003
  • Objective quality measurement schemes that incorporate properties of the human auditory system. The basilar membrane (BM) acts as a spectrum analyzer, spatially decomposing the signal into frequency components. Filterbanks were used to complementing the linearity of BM. Each filterbank is an implementation or the Equivalent rectangular Bandwidth (ERB), gammachirp function. This filterbank is level-dependent asymmetric compensation filters. And for the validation of the auditory model, we calculate the calculated perceived difference(CPD).

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Prediction of Tidal Regime According To Garolim Tidal Power Plant operation (가로림만 조력발전소 가동에 따른 조석체계 변화 예측)

  • Kang, Sok-Kuh;Lee, Kwang-Soo;Park, Jin-Soon;Yum, Ki-Dai;Jung, Kyung-Tae;Jang, Chan-Joo
    • New & Renewable Energy
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    • 제3권2호
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    • pp.3-10
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    • 2007
  • Tidal regime change with general hydrolic condition change is examined, according to Garolim Tidal Power Plant (TPP) operation. Numerical model has been developed for the Yellow and East China Seas region, in order to consider the tidal regime change by the TPP operation. The changes of tidal elevation and tidal current inside the Garolim bay are also investigated in details, along with examining the change of the tidal flat area with operation. The field measurement for the tide and current have been carried out for the validation of the numerical model and for understanding the state of current system in the present state.

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Measurement of skin moisture using a FT-NIR spectrometer

  • Suh, Eun-Jung;Woo, Young-Ah;Kim, Hyo-Jin
    • Proceedings of the PSK Conference
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.218.3-218.3
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    • 2003
  • In this study, a FT-NIR spectroscopy was used to determine skin moisture. NIR diffuse reflectance spectra were collected from separated dorsal and abdominal hairless mouse skin. Partial least squares regression (PLSR) was applied to develop calibration models that determine the water content. The seven spectra regions, such as 833-2500, 1100-2250, 1100-1750, 1750-2250, 1200-1600, 1800-2200, and 1200-2200 except 1600-1800 nm, were investigated for the best model by PLSR. The developed model predicted skin moisture for validation set with a standard errors of prediction (SEP) of 4.43%, when used 833-2500 nm. (omitted)

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Measurement of Care Coordination between Korean Medicine and Western Medicine: Development and Validation of an Instrument (한.양방 협진의 진료협력수준 측정도구개발 및 타당도 연구)

  • Park, Minjung;Choi, Byunghee;Baek, Yun Hui;Park, Jeong Hye
    • Journal of Society of Preventive Korean Medicine
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    • 제19권1호
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    • pp.71-82
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    • 2015
  • Objective : The purpose of this study is to present the desirable model for the promotion of care coordination between Korean Medicine and Western Medicine and develope the instrument to measure the level of coordination. Moreover, we verified the validity and reliability of the developed Instrument. Method : In this study, We developed the 16 items regarding care coordination in Korean Medicine and Western Medicine by literature review and expert interviews. In addition, we verified the validity and reliability of the instrument as a methodological research. Results : We developed two factors such as 'Inter-professional activities' and 'Organizational support' as the instrument to measure the level of care coordination, and each of seven, eight total of 15 measurement items are listed. Conclusion : Since the legal permission, the level and type of care coordination and the effects of them are needed to be checked. So, the measurement instrument driven by this study has a political signification in healthcare system specially in these times. In addition, by utilizing this instrument, we propose to perform a variety of future studies on the levels of healthcare coordination and related outcomes.

Particle image velocimetry measurement of complex flow structures in the diffuser and spherical casing of a reactor coolant pump

  • Zhang, Yongchao;Yang, Minguan;Ni, Dan;Zhang, Ning;Gao, Bo
    • Nuclear Engineering and Technology
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    • 제50권3호
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    • pp.368-378
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    • 2018
  • Understanding of turbulent flow in the reactor coolant pump (RCP) is a premise of the optimal design of the RCP. Flow structures in the RCP, in view of the specially devised spherical casing, are more complicated than those associated with conventional pumps. Hitherto, knowledge of the flow characteristics of the RCP has been far from sufficient. Research into the nonintrusive measurement of the internal flow of the RCP has rarely been reported. In the present study, flow measurement using particle image velocimetry is implemented to reveal flow features of the RCP model. Velocity and vorticity distributions in the diffuser and spherical casing are obtained. The results illuminate the complexity of the flows in the RCP. Near the lower end of the discharge nozzle, three-dimensional swirling flows and flow separation are evident. In the diffuser, the imparity of the velocity profile with respect to different axial cross sections is verified, and the velocity increases gradually from the shroud to the hub. In the casing, velocity distribution is nonuniform over the circumferential direction. Vortices shed consistently from the diffuser blade trailing edge. The experimental results lend sound support for the optimal design of the RCP and provide validation of relevant numerical algorithms.