• Title/Summary/Keyword: correlation measure

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How to Measure Nonlinear Dependence in Hydrologic Time Series (시계열 수문자료의 비선형 상관관계)

  • Mun, Yeong-Il
    • Journal of Korea Water Resources Association
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    • v.30 no.6
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    • pp.641-648
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    • 1997
  • Mutual information is useful for analyzing nonlinear dependence in time series in much the same way as correlation is used to characterize linear dependence. We use multivariate kernel density estimators for the estimation of mutual information at different time lags for single and multiple time series. This approach is tested on a variety of hydrologic data sets, and suggested an appropriate delay time $ au$ at which the mutual information is almost zerothen multi-dimensional phase portraits could be constructed from measurements of a single scalar time series.

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A Study on The Determination Method of Engineering Characteristic Values by QFD (품질기능전개를 통한 품질특성값 결정방법에 관한 연구)

  • 강지호;박명규
    • Journal of the Korea Safety Management & Science
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    • v.2 no.4
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    • pp.113-124
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    • 2000
  • First, in order to improve selecting method of quality characteristic level desired by customers, S/N(Signal-to-Noise) ratio of Taguchi in larger-the-better characteristics was applied. Second, the Matrix classification standard of ACE(Attribute Categorization Evaluation) is presented using KANO model on difference analysis of importance and satisfaction through questionnaire from customers. This is for reflecting the diverse EC which customers want in EC quality sufficiently. Also, establishing sales point will be helpful in business strategy through presenting types that are able to decide planning quality. Third, the important measure of EC about correlation among quality characteristics and a new weight of EC are calculated depending on importance of EC and the weight of customer attribute and materials of relationship matrix through correlation matrix analysis.

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Estimation of the Pipe Thickness using the Variation of the Group Velocity (군속도 변화를 이용한 배관 두께 측정)

  • Han, Seung-Hee;Hwang, Jong-Myung;Lee, Jang-Myung
    • The Journal of Korea Robotics Society
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    • v.5 no.1
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    • pp.32-40
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    • 2010
  • This paper proposes the technique of estimating the pipe thickness using the measured group velocity. To measure the group velocity from the accelerometer data in the frequency domain, Wigner-Ville distribution is utilized, which interprets the waveform of the shock wave. Using this measured group velocity, this paper proposes the technique to estimate the thickness of pipes with the impact on the pipe. The group velocity is estimated by the modeling correlation between the group velocity and the thickness of the pipe based on the propagation velocities. The correlation model between thickness and group velocity has been proved through the real experiments. The measured group velocity in the frequency-domain is the maximum at the center frequency of the bending waves in the modeling of the group velocity. In addition to these, a smoothing technique for analyzing lamb wave Wigner-Ville distribution has been introduced to improve the reliability of the data acquisition.

A Study on The Determination Method of Engineering Characteristic Values by QFD (품질기능개선을 통한 품질특성값 결정방법에 관한 연구)

  • 강지호;박명규
    • Proceedings of the Safety Management and Science Conference
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    • 2000.05a
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    • pp.481-490
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    • 2000
  • First, in order to improve selecting method of quality characteristic level desired by customers, S/H(Signal-to-Noise) ratio of Taguchi in larger-the-better characteristics was applied. Second, the Matrix classification standard of ACE(Attribute Categorization Evaluation) is presented using KANO model on difference analysis of importance and satisfaction through questionnaire from customers. This is for reflecting the diverse EC which customers want in EC quality sufficiently. Also, establishing sales point will be helpful in business strategy through presenting types that are able to decide planning quality. Third, the important measure of EC about correlation among quality characteristics and a new weight o( EC are calculated depending on importance of EC and the weight of customer attribute and materials of relationship matrix through correlation matrix analysis.

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EEG Asymmetry Changes by the Left and the Right SMR Brainwave of the Computer Learning Versus the Paper and Pencil Learning

  • Kwon, Hyung-Kyu;Cho, Jang-Sik
    • Journal of the Korean Data and Information Science Society
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    • v.18 no.4
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    • pp.1073-1079
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    • 2007
  • The purpose of this study is to present the relationship between the computer learning and the paper and pencil learning through the math learning (simple computation and complex computation) and the cartoon learning and text learning. The canonical correlation and pairwise t-test of the SMR asymmetry brainwaves of the left and the right brain show the brainwaves with the respect to the manner in which they process information during the specified task by identifying the relative activity of the brainwaves of the left and the right brain. SMR brainwave which known as the scientific measure tool for the activity and the function of the neuronal cell were found to predict the level of the awakening to check the readiness of study preparation. Computer education as a medium of the individualized and the repetitive education shows the difference from the paper and the pencil test in the respect of the differences and the relationship of the SMR brainwave of the learning process.

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Design of Partial Discharge detection Sensor Module and Correlation for Power Incoming/Distributer (수/배전반의 부분방전 검출 모듈 설계와 상관관계)

  • Cho, Do-Hyeoun
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.10
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    • pp.243-247
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    • 2014
  • In this paper, we design two types of the sensor module to measure the partial discharge causing failures and electric fires for power incoming/distributer. And evaluate the performance thereof. Analyze the correlation of the phase current and the partial discharge and overheating. Proposes to apply the stability index by utilizing the analyzed information and use in order to prevent the failure or electrical fire of the power incoming/distributer.

Galaxy clustering from the UKIDSS DXS

  • Kim, Jae-U
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.36.1-36.1
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    • 2012
  • Recent wide and deep surveys allow us to investigate the large scale structure of the Universe at high redshift. We present studies of the clustering of high redshift galaxies, using reprocessed UKIDSS DXS catalogue. We measure the angular correlation function of high redshift galaxies which is Extremely Red Objects (EROs). Firstly we found that their angular correlation functions can be described by a broken power-law. We also found that red or bright samples are more strongly clustered than those having the opposite characteristics, and that old, passive EROs are found to be more clustered than dustry, star-forming EROs. Additionally the average halo mass and other properties were estimated using the halo model. Finally the observed clustering of EROs was compared with predictions from the cosmological simulation.

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Correlation Study between Brain Atrophy and Risk Factors for Cerebrovascular Disease (노화에 관련된 뇌위축과 뇌혈관 질환의 위험인자와의 상관관계 연구)

  • Ko, Heung;Moon, Jo Ho;Kim, Ki Tae;Shin, Seon Mi
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.28 no.2
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    • pp.200-205
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    • 2014
  • Based on the way we have created to measure the brain atrophy of pons, frontal lobe, sylvian fissure, ventricle, cerebellum, we analyzed the correlation with age. We confirmed whether the brain atrophy due to hypertension, diabetes, hyperlipidemia, drinking, smoking is increasing. Brain deficiency(髓海不足), Brain dissatisfied(腦爲之不滿), Brain Consume(腦髓消烁) listed in Donguibogam(東醫寶鑑) have to be diagnosed with brain atrophy induced by developmental disorders, diseases, aging. Sylvian fissure is well reflected brain atrophy progressed by aging. And brain atrophy increased in hypertension, diabetes, hyperlipidemia, drinking, smoking is well reflected at Sylvian fissure.

Optimal Gas-Flow Conditions for Stabilization of Lean-Burn Combustion (희박연소 안정화를 위한 가스유동장 조건에 관한 연구)

  • 이기형;이창식
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.3
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    • pp.763-770
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    • 1995
  • Gas flow characteristics within the cylinder is important factors in impoving lean combustion stability. This paper shows the effects of various flow fields generated by a swirl control valve(SCV) on combustion process in a 4-valve spark ignition engine. An impulse swirl/tumble meter was used to elucidation the steady-state flow characteristics, and a rotating grating type LDV was developed to measure the mean velocity and tunbulence intensity in relation to the crank angle. These methodologies were applied to clarify the correlation between gas flow characteristics and combustion stability at a lean air fuel ratio. An analysis of the correlation revealed the gas flow conditions required to optimize a lean-burn system.

A Study on the Correlation of Vehicle Propeller Shaft and Axle Vibration (차량 추진축과 엑슬 진동의 상관성에 관한 연구)

  • 장일도;한기석;홍동표
    • Journal of KSNVE
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    • v.10 no.4
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    • pp.596-601
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    • 2000
  • Propeller shaft is one of the main excitation source in the vehicle driveline. This paper presents the correlation of the propeller shaft and axle vibration. 10 D.O.F. lumped mass model is constructed to simulate the dirveline. Experimental apparatus is constructed to verify the simulation model and to measure the vibration signal of lthe driveline. The results of simulation and experiments show that propeller shaft excitation is 2nd harmonic of the rotational frequency. Axle housing vibration signal shows that axle resonate with 2nd harmonic of excitation frequency due to universal joint effect.

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