• Title/Summary/Keyword: correlation coefficients

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Human Interface Design using Pattern Analysis of Multichannel EMG signals (다채널 EMG 신호의 패턴 해석을 이용한 휴먼 인터페이스의 설계)

  • 이용희;이경호;서재성;황기현
    • Proceedings of the IEEK Conference
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    • 2003.07c
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    • pp.2895-2898
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    • 2003
  • In this study, our primary goal is to classify the EMG(electromyographic) signals including the specific patterns related to hand motions in an arm. To do this, the EMG recognition method based on the LP coefficients and delay between multi-channels obtained by cross-correlation function is presented. The study consists of three functional parts, which are pans for obtaining the EMG signals from am muscle, analyzing LP coefficients and delay parameter obtained by cross-correlation function, and recognizing specific patterns. In the experiment, the result of the present method is compared with the results of the conventional methods. We expect that the results of this study is very effective in the mobile computer and wearable computer environment.

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Electrochemical Effectiveness Factors for Butler-Volmer Reaction Kinetics in Active Electrode Layers of Solid Oxide Fuel Cells

  • Nam, Jin Hyun
    • Journal of Electrochemical Science and Technology
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    • v.8 no.4
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    • pp.344-355
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    • 2017
  • In this study, a numerical approach is adopted to investigate the effectiveness factors for distributed electrochemical reactions in thin active reaction layers of solid oxide fuel cells (SOFCs), taking into account the Butler-Volmer reaction kinetics. The mathematical equations for the electrochemical reaction and charge conduction process were formulated by assuming that the active reaction layer has a small thickness, homogeneous microstructure, and high effective electronic conductivity. The effectiveness factor is defined as the ratio of the actual reaction rate (or equivalently, current generation rate) in the active reaction layer to the nominal reaction rate. From extensive numerical calculations, the effectiveness factors were obtained for various charge transfer coefficients of 0.3-0.8. These effectiveness data were then fitted to simple correlation equations, and the resulting correlation coefficients are presented along with estimated magnitude of error.

Image Retrieval Using Texture Features BDIP and BVLC (BDIP와 BVCL의 질감특징을 이용한 영상검색)

  • 천영덕;서상용;김남철
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.183-186
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    • 2001
  • In this paper, we first propose new texture features, BVLC (block variation of local correlation coefficients) moments, for content-based image retrieval (CBIR) and then present an image retrieval method based on the fusion of BDIP and BVLC moments. BDIP uses the local probabilities in image blocks to extract valley and edges well. BVLC uses the variations of local correlation coefficients in images blocks to measure texture smoothness well. In order not to be affected with the movement, rotation, and size of an object, the first and second moments of BDIP and BVLC are used for CBIR. Corel DB and Vistex DB are used to evaluate the performance of the proposed retrieval method. Experimental results show that the presented retrieval method yields average 12% better performance than the method using only BDIP or BVLC moments and average 13% better performance than the method using wavelet moments.

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Pitfall in calibration development - "chance correlation + wishful thinking" - an example of pH determination in grass silages

  • Tillmann, Peter;Horst, Hartmut
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1275-1275
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    • 2001
  • The pH value of grass silages is one important parameter to determine the quality of the forages. In an attempt to use NIRS spectra taken for other quality parameter of grass silage it has been shown that a good correlation between NIR spectra of the dried forage and pH value of the fresh forage could be determined. Further investigations revealed that the B coefficients of the pH value calibration were almost the same as the B coefficients of the sugar calibration multiplied with -1. And indead the pH value - in the fresh sample material - of the calibration set is strongly correlated with the sugar concentration - in the dried sample material. It is concluded that next to scientific tools in research the scientist and the user of NTRS equippment has to scrutinze his own work. Examples are given. NIRS is a powerfull technique, but pitfalls are present in surplus.

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A Comparative Study on the Chemical Compositions of Precipitations in Sungnam City of Kyunggi Province, Inchon City, Kangneung City of Kangwon Province, and Chongwon-gun of Chungbuk Province (경기도 성남시, 인천시, 강원도 강릉시, 충북 청원군 강수의 화학적 성분에 관한 비교 연구)

  • 박국태;문경언
    • Journal of Environmental Science International
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    • v.4 no.3
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    • pp.285-294
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    • 1995
  • A comparative study on the chemical compositions of precipitations from February 1993 to April 1993 in Sungnam city of Kyunggi province, Inchon city, Kangneung city of Kangwon province, and Chongwon-gun of Chungbuk province has been performed. The metal cation and anion concentrations were measured by atomic absorption spectrometer and ion liquid chromatography, respectively. pH/Ion meter and direct nesslerization method were used for the concentration measurements of $H^+$ and $NH^{4+}$ ions, respectively. The quantitative orders of the cation and anion average concentrations, correlation coefficients between the ion concentrations, and pH values are used for chemical analysis on the environmental pollution and pollutant sources in the urban, surburban, seaside, and rural areas of the Korean Peninsula.

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An Application of Water quality model for a Stream in Rural Watersheds (농촌유역 소하천에 대한 수질모형의 적용)

  • Park, Young-Jin;Kwun, Soon-Kuk
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2002.10a
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    • pp.361-364
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    • 2002
  • The WASP model was applied to Bokha stream with 8.4km of its main stem located in Ichon-gun, Kyonggi province in Korea. The stream was divided into 26 segments with each of 400m length, and 5 segments were embraced boundaries of its tributaries. The parameters of the model were calibrated by the trial and error method to minimize differences between observed and simulated concentration of water quality constituents. The correlation coefficients for DO, $NO_3-N,\;PO_4-P$ and organic P showed high values providing the ability of simulation. The correlation coefficients for BOD and $NH_3-N$ showed low values in both calibration and verification test.

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Experimental investigation of characteristics of torsional wind loads on rectangular tall buildings

  • Li, Yi;Zhang, J.W.;Li, Q.S.
    • Structural Engineering and Mechanics
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    • v.49 no.1
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    • pp.129-145
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    • 2014
  • In order to investigate the characteristics of torsional wind loads on rectangular tall buildings, five models with different rectangular cross-sections were tested in a boundary wind tunnel. Based on the test results, the RMS force coefficients, power spectrum densities as well as vertical correlation functions of torsional wind loads were analyzed. Formulas that took the side ratio as parameters were proposed to fit the test results above. Comparisons between the results calculated by the formulas and the wind tunnel measurements were made to verify the reliability of the proposed formulas. An simplified expression to evaluate the dynamic torsional wind loads on rectangular tall buildings in urban terrain is presented on basis of the above formulas and has been proved by a practical project. The simplified expressions as well as the proposed formulas can be applied to estimate wind-induce torsional response on rectangular tall buildings in the frequency domain.

Wind pressures on a large span canopy roof

  • Rizzo, Fabio;Sepe, Vincenzo;Ricciardelli, Francesco;Avossa, Alberto Maria
    • Wind and Structures
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    • v.30 no.3
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    • pp.299-316
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    • 2020
  • Based on wind tunnel tests, this paper investigates the aerodynamic behavior of a large span canopy roof with elliptical plan and hyperbolic paraboloid shape. The statistics of pressure coefficients and the peak factor distributions are calculated for the top and bottom faces of the roof, and the Gaussian or non-Gaussian characteristics of the pressure time-histories in different areas of the roof are discussed. The cross-correlation of pressures at different positions on the roof, and between the top and bottom faces is also investigated. Combination factors are also evaluated to take into account the extreme values of net loads, relevant to the structural design of canopies.

CLASSIFICATION OF BRAIN EVOKED POTENTIAL USING CORRELATION COEFFICIENTS AND NEURAL NETWORK (상관계수와 뉴럴 네트워크를 이용한 뇌 유발 전위의 분류)

  • Chee, Young-Joon;Park, Kwang-Suk
    • Proceedings of the KOSOMBE Conference
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    • v.1995 no.11
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    • pp.189-192
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    • 1995
  • In Visually Evoked Potentials(VEP) or Auditory Evoked Potentials(AEP), the components by the stimulation and the components which are irrelevant to the stimulation(noise or nonstationary spontaneous EEG) are mixed together. So one should average hundreds of EP waves to extract the components by the stimulation only. In this study, we have classified EP's, which are the responses of the different stimulations and different states of subjects. To classify the EP waves, the cross-correlation coefficients and neural network method(error back propagation) are used and compared.

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A Study on the Inference of Product Design Elements by Fuzzy Decision Making Model (퍼지 의사결정 모델에 의한 감성제품 디자인 요소의 추론에 관한 연구)

  • Yang, Seon-Mo;Lee, Sun-Yo;An, Beom-Jun
    • Journal of the Ergonomics Society of Korea
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    • v.17 no.1
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    • pp.37-46
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    • 1998
  • A human sensibility ergonomics design supporting system was applied to the product development for the customer's satisfaction based on ergonomics technology. The system is composed of three major subsystems such as customer's sensibility analysis, inference mechanism, and presentation technology. The main approaches of the system are to analyze customer's sensibilities and to translate them into product design elements. The purpose of this paper is to develop a design supporting system in which the relationship between customer's sensibility and product design elements is reasoned by a MADM(Multi-Attribute Decision Making) fuzzy model. In this model, three variables such as multiple correlation coefficients, partial correlation coefficients, and category scores were used in reasoning process. The weighted value of the words were also considered in fuzzy decision process. As a case study, the design supporting system with the MADM fuzzy model was applied to the personnel computer design.

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