• Title/Summary/Keyword: Cross-National

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GLOBAL GENERALIZED CROSS VALIDATION IN THE PRECONDITIONED GL-LSQR

  • Chung, Seiyoung;Oh, SeYoung;Kwon, SunJoo
    • Journal of the Chungcheong Mathematical Society
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    • v.32 no.1
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    • pp.149-156
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    • 2019
  • This paper present the global generalized cross validation as the appropriate choice of the regularization parameter in the preconditioned Gl-LSQR method in solving image deblurring problems. The regularization parameter, chosen from the global generalized cross validation, with preconditioned Gl-LSQR method can give better reconstructions of the true image than other parameters considered in this study.

Bending Creep Property of Cross-Laminated Woods Made With Six Domestic Species

  • Byeon, Jin-Woong;Kim, Tae-Ho;Yang, Jae-Kyung;Byeon, ee-Seop;Park, Han-Min
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.6
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    • pp.689-702
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    • 2017
  • In this study, with the view to using effectively small and medium diameter Korean domestic woods as structural materials, cross-laminated woods were manufactured by using six species of Korean domestic softwoods and hardwoods, and bending creep properties were investigated for each species. The creep curves showed the shape of the exponential function plot, and the creep curves after 1 hour were able to estimate by fitting it to the power law. The initial and creep compliances of cross-laminated woods showed the higher values in wood species with a low density than in that with a high density. And by cross-laminating, the initial and creep compliances perpendicular to the grain considerably decreased, the extent of the decrease was found to be greater in creep deformation than in initial deformation. The creep anisotropies of cross-laminated woods were considerably decreased by cross-laminating. The relative creep of $C_{\bot}$ type composed of perpendicular-direction lamina in the faces decreased 0.59 - 0.64 times compared to that of $P_{\bot}$ type composed of perpendicular-direction laminae in all layers, and that for $C_{\parallel}$ type composed of parallel-direction laminae in the faces increased 1.5 - 1.6 times compared to that of $P_{\parallel}$ type composed of parallel-direction laminae in all layers.

A Study on the Curing Property of the Epoxy Resin (에폭시수지의 경화특성에 관한 연구)

  • Lee, Jin;Lee, Eun-Hak;Song, Hee-Su;Kim, Tae-Seoung
    • Proceedings of the KIEE Conference
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    • 1988.11a
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    • pp.246-248
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    • 1988
  • The electrical insulation characteristics of the Epoxy resin is generally depended upon the cross-Link. Therefore, when the Epoxy is cured the full cross-Link must be gotten to obtain the best electrical insulation property. This paper alms at examining the cure condition to get the best cross-link. The Epoxy used in this experiment is DGEBA, the curing materiel is MNA, and the accellator is tertiary amine. In this study, the best curing condition of cross-link is suggested by analysing the each Epoxy resin which is differenty cured according Lo the variable temperatures and curing times.

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A Study on the Lightweight Design of a Cross Beam for Railway Passenger Coach (철도객차용 크로스 빔의 경량화 설계에 관한 연구)

  • Jang, Deuk-Yul;Jeon, Hyung-Yong
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.5
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    • pp.126-133
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    • 2017
  • This report investigates the stress distribution according to the location and shape change of the circular hole for the lightweight design of the cross beam of a railway passenger car and studies the lightweight design. To design a lightweight cross beam with a circular hole, we selected the non-circular crossbeam as a basic model, examined the stress distribution and displacement by position and determined the location, shape, size and quantity of the hole for light weight. We analyzed the effects of the position and shape of the hole on the maximum equivalent stress and displacement. The influencing factors were set as the design parameters, and the stress value was examined according to the variation of each variable. By considering the stress value according to the change of each variable and selecting the design parameter with the narrowest scattering value of the stress at each position of the hollow cross beam with various hole positions and shapes, we studied a cross beam with a circle hole under identical load condition to have an equal stress distribution to that of a non-circular cross beam.

Partial Photoionization Cross Section of Collinear eZe Helium: Numerical Confirmation of Semiclassical Predictions

  • Lee, Min-Ho;Choi, Nark Nyul
    • Journal of the Korean Physical Society
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    • v.73 no.10
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    • pp.1486-1494
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    • 2018
  • Based on the semiclassical theory of chaotic scattering, Tanner et al. [J. Phys. B 40, F157 (2007)] proposed the fluctuation in the partial photoionization cross section of helium below the double-ionization threshold would show the same characteristics as in the total cross section, predicting that the Fourier spectrum of the fluctuation reveals peaks at the classical actions of closed triple collision orbits and the amplitude of the fluctuation decreases algebraically as the energy approaches the double-ionization threshold. In that paper, however, the predictions were not clearly confirmed due to the lack of experimental data with sufficient accuracy. So instead, we calculate the partial photoionization cross sections of collinear eZe helium for the energy range from the single-ionization threshold $I_{20}$ to $I_{32}$ in order to numerically confirm the predictions. Analysis of the fluctuation in the partial cross section shows that the predictions are indeed valid. Our findings mean that the fluctuation in the partial photoionization cross section can be described by classical triple collision orbits in the semiclassical limit. Thus it explains in a natural way the mirroring and mimicking structures observed in cross section signals for different ionization channels.

Effect of Cross-bar Length on Luminous Efficacy in AC-PDP with Fence Electrode Stricture

  • Nam, Hyung-Woo;Choi, Yong-Suk;Bae, Hyo-Won;Kim, Yun-Gi;Ok, Jung-Woo;Kim, Dong-Hyun;Lee, Ho-Jun;Lee, Hae-June;Park, Chung-Hoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.721-724
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    • 2009
  • In this paper, we proposed fence electrode structures. The experimental structures change cross-bar length as 145, 105, 65 and $30{\mu}m$ to improve the electro-optical characteristics. The proposed structures improve the addressing time and luminous efficacy compared with the T145 structure which has the cross-bar length of $145{\mu}m$ as the reference. Especially, in the case of the T30 structure with cross-bar length of $30{\mu}m$, it gains lower power consumption by 34%, and higher luminous efficacy by 20% than those of the reference structure.

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Modeling of a Dual Stator Induction Generator with and Without Cross Magnetic Saturation

  • Slimene, Marwa Ben;Khlifi, Mohamed Arbi;Fredj, Mouldi Ben;Rehaoulia, Habib
    • Journal of Magnetics
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    • v.20 no.3
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    • pp.284-289
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    • 2015
  • This paper discusses general methods of modelling magnetic saturation in steady-state, two-axis (d & q) frame models of dual stator induction generators (DSIG). In particular, the important role of the magnetic coupling between the d-q axes (cross-magnetizing phenomenon) is demonstrated, with and without cross-saturation. For that purpose, two distinct models of DSIGs, with and without cross-saturation, are specified. These two models are verified by an application that is sensitive to the presence of cross-saturation, to prove the validity of these final methods and the equivalence between all developed models. Advantages of some of the models over the existing ones and their applicability are discussed. In addition, an alternative is given to evaluate all saturation factors (static and dynamic) by just calculating the static magnetizing inductance which is simply the magnitude of the ratio of the magnetizing flux to the current. The comparison between the simulation results of the proposed model with experimental results gives a good correspondence, especially at startup.

Automatic Cross-calibration of Multispectral Imagery with Airborne Hyperspectral Imagery Using Spectral Mixture Analysis

  • Yeji, Kim;Jaewan, Choi;Anjin, Chang;Yongil, Kim
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.3
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    • pp.211-218
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    • 2015
  • The analysis of remote sensing data depends on sensor specifications that provide accurate and consistent measurements. However, it is not easy to establish confidence and consistency in data that are analyzed by different sensors using various radiometric scales. For this reason, the cross-calibration method is used to calibrate remote sensing data with reference image data. In this study, we used an airborne hyperspectral image in order to calibrate a multispectral image. We presented an automatic cross-calibration method to calibrate a multispectral image using hyperspectral data and spectral mixture analysis. The spectral characteristics of the multispectral image were adjusted by linear regression analysis. Optimal endmember sets between two images were estimated by spectral mixture analysis for the linear regression analysis, and bands of hyperspectral image were aggregated based on the spectral response function of the two images. The results were evaluated by comparing the Root Mean Square Error (RMSE), the Spectral Angle Mapper (SAM), and average percentage differences. The results of this study showed that the proposed method corrected the spectral information in the multispectral data by using hyperspectral data, and its performance was similar to the manual cross-calibration. The proposed method demonstrated the possibility of automatic cross-calibration based on spectral mixture analysis.