• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.133-137
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• 2002

In this paper, the $CF_{4}$ decomposition rate are investigated for a simulated three plasma reactors which are metal particle reactor, spiral wire reactor and reactor with porous dielectric as applied voltage. The $CF_{4}$ decomposition rate by plasma reactor with porous dielectric had a gain of 20~25[%] over that by plasma reactor with spiral wire or metal particle electrode. The $CF_{4}$ decomposition efficiency increases with increasing applied voltage up to the critical voltage for spark formation. The $CF_{4}$ decomposition efficiency of metal particle reactor was about 80[%] at AC 24[kV]. However, decomposition efficiency is more than 90% in case of the reactor with porous dielectric. we think, the reactor with porous dielectric should be much better than other reactors for $CF_{4}$ decomposition.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.205-206
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• 2011

In this paper, algorithm for fault classification and detection of generator dropping using wavelet singular value decomposition (WSVD) is proposed. Busan area upper 345kV is modeled and generator dropping is simulated in EMTP-RV. Characteristic of generator dropping is analyzed and this algorithm is deducted by calculating WSVD in MATLAB.

• Bulletin of the Korean Mathematical Society
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• v.32 no.2
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• pp.191-200
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• 1995

Simple Lie albegras over algebraically closed field with characteristic p > 7 were classified by H. Strade and R. L. Wilson in 1991 [7]. All modular representations of simple Lie algebras, however, are not classified although some restricted modular representations have been done earlier by Curtis and Steinberg. In connection with this, we would like to decompose basic $sp_4$(F)-modules $sl_4$-(F) and $gl_4$(F) over nonzero characteristic by way of characteristic zero case.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.6
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• pp.543-550
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• 2002

In this paper, the $CF_4$ decomposition rate and by-product were investigated for two simulated plasma reactors which are metal particle reactor and spiral wire reactors as a function of mixed gases. The $CF_4$ decomposition rate by plasma reactor with metal particle electrode had a gain of 20~25% over that by plasma reactor with spiral wire electrode. The $CF_4$ decomposition efficiency increases with increasing applied voltage up to the critical voltage for spark formation. The $CF_4$ decomposition efficiency of metal particle reactor was about 80% at AC 24kV. The $CF_4$ decomposition rate used Ar-$N_2$ as base gas was the highest among three base gases of $N_2$, $Ar-N_2$, air. The by-products of the $N_2$, $N_2Ar$ base as were similar, but in case of air base they were different.

• Korean Journal of Remote Sensing
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• v.33 no.4
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• pp.351-358
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• 2017

A new method to decompose the footprints of marine atmosphere boundary layer (MABL) on Synthetic Aperture Radar (SAR) imagery into characteristic spatial scales is proposed. Using two-dimensional Empirical Mode Decomposition (EMD) we obtain three Intrinsic Mode Functions (IMFs), which mainly present longitudinal rolls, three-dimensional cells and atmospheric gravity waves (AGW). The rolls and cells have spatial scales between 3.0 km and 3.8 km and between 5.3 km and 7.1 km, respectively. Based on previous observations and mixed-layer similarity theory, we estimated MABL's depths that vary from 0.95 km to 1.2 km over the rolls and from 3.0 km to 3.8 km over the cells. The AGW has maximum spectrum at 14.3 km wavelength. The method developed in this work can be used to decompose other satellite imageries into individual features through characteristic spatial scales.

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.268-277
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• 2012

The thermal decomposition characteristic of waste PVC wires has been studied by using TGA and fixed-bed reactor. The experimental conditions of decomposition temperatures, air flow rates and weight ratio of CaO/PVC were considered in this work. To verify the effectiveness of CaO addition to remove HCl and toxic gases generated from thermal decomposition of PVC wire, the gaseous products obtained from the thermal decomposition of PVC were analyzed by GC/MS(Gas Chromatograph and Mass Spectrometry). To investigate the effect of CaO in thermal decomposition of PVC, liquid products were also analyzed by GC/MS. And the effect of decomposition temperature, air flow rate and CaO/ PVC weight ratio on the yield of liquid, gas and residue fraction have been also studied. From this work, it was found that the removal amount of HCl generated from thermal decomposition of PVC increased with increase of CaO addition.

• Journal of Korean Association for Spatial Structures
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• v.19 no.2
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• pp.101-108
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• 2019

In this paper, the characteristic of intrinsic mode function(IMF) and its orthogonalization of ensemble empirical mode decomposition(EEMD), which is often used in the analysis of the non-linear or non-stationary signal, has been studied. In the decomposition process, the orthogonal IMF of EEMD was obtained by applying the Gram-Schmidt(G-S) orthogonalization method, and was compared with the IMF of orthogonal EMD(OEMD). Two signals for comparison analysis are adopted as the analytical test function and El Centro seismic wave. These target signals were compared by calculating the index of orthogonality(IO) and the spectral energy of the IMF. As a result of the analysis, an IMF with a high IO was obtained by GSO method, and the orthogonal EEMD using white noise was decomposed into orthogonal IMF with energy closer to the original signal than conventional OEMD.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.386-392
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• 1996

A numerical method based on genetic algorithms was introduced to characterize the grain-size distribution more effectively. This technique was proved significant particularly for multimodal size distributions, as was verified for samples from Korea Strait continental shelf. Sediment samples collected from the Korea Strait continental shelf revealed that $96\%$ of the grain-size distributions were multimodal. Therefore, the use of grain-size parameters was not the ideal method. As an alternative method, the decomposition of sue curves into elementary normal component curves was used. Means and standard deviations of 593 decomposed normal components were calculated by a numerical method from 268 size curves of Korea Strait sediments. The mean values of decomposed normal components showed peaks at $1\~3\phi\;and\;7\~9\phi$ size classes. The plot of mean and standard deviation values of the coarse fraction normal components on the map showed a characteristic areal distribution. The characteristic distribution was found to derive from underlying Pleistocene sediment on the basis of sea bottom geologic distribution of the area. The method of decomposition into normal components was found to be more effective than the analysis using traditional grain-size parameters in investigation of multimodal size distribution of Korea Strait shelf sediment.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.431-441
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• 1998

Polyester microfiber fabrics were decomposed at 100, 110, 120 and 140 t of temperature and 0.5, 1.0 and 1.5% of sodium propyleneglycolate/propyleneglycol solution(SPG-PG). Characteristic decomposition feature and physical and chemical properties of the decom- posed PET microfiber fabrics were discussed. The activation energy was 18.77 kcal/mol and the dyeability of the decomposed PET microfiber fabrics was found to be improved as it was supported by the examined K/S values. Up to the 20% of the weight loss of the PET microfiber fabrics, K/S values incresed with increasing the weight loss. The melting temperature of PET microfiber fabrics decomposed by SPG-PG showed no fundamental change. Tensile strength of the decomposed PET microfiber fabrics decreased linearly in accordance with the increased the weight loss of the PET microfiber fabrics. The moisture regain and the tactilities increased in accordance with the increased the weight loss of the PET microfiber fabrics.

• ETRI Journal
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• v.35 no.5
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• pp.880-888
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• 2013

The preexisting pairings ate, $ate_i$, R-ate, and optimal-ate use q-expansion, where q is the size of the defining field for the elliptic curves. Elliptic curves with small embedding degrees only allow a few of these pairings. In such cases, efficiently computable endomorphisms can be used, as in [11] and [12]. They used the endomorphisms that have characteristic polynomials with very small coefficients, which led to some restrictions in finding various pairing-friendly curves. To construct more pairing-friendly curves, we consider ${\mu}$-expansion using the Gallant-Lambert-Vanstone (GLV) decomposition method, where ${\mu}$ is an arbitrary integer. We illustrate some pairing-friendly curves that provide more efficient pairing from the ${\mu}$-expansion than from the ate pairing. The proposed method can achieve timing results at least 20% faster than the ate pairing.