• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.278-281
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• 2000

Matching pursuit algorithm is a signal expansion technique whose efficiency for motion compensated residual image has already been demonstrated in the MPEG-4 framework. However, one of the practical concerns related to applying matching pursuit algorithm to real-time scalable video coding is its massive computation required for finding dictionary elements. In this respective, this paper proposes a fast algorithm, which is composed of three sub-methods. The first method utilizes the property of symmetry in 1-D dictionary element and the second uses mathematical elimination of inner product calculation in advance, and the last one uses frequency property of 2-D dictionary. Experimental results show that our algorithm needs about 30% computational load compared to the conventional fast algorithm using separable property of 2-D gabor dictionary with negligible quality degradation.

• Bulletin of the Korean Mathematical Society
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• v.46 no.1
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• pp.99-105
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• 2009

Let $M=H_1{\cup}_SH_2$ be a Heegaard splitting of a 3-manifold M, D be an essential disk in $H_1$ and A be an essential annulus in $H_2$. Suppose D and A intersect in one point. First, we show that a Heegaard splitting admitting such a (D, A) pair satisfies the disjoint curve property, yet there are infinitely many examples of strongly irreducible Heegaard splittings with such (D, A) pairs. In the second half, we obtain another Heegaard splitting $M=H'_1{\cup}_{S'}H'_2$ by removing the neighborhood of A from $H_2$ and attaching it to $H_1$, and show that $M=H'_1{\cup}_{S'}H'_2$ also has a (D, A) pair with $|D{\cap}A|=1$.

• Journal of Applied Biological Chemistry
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• v.53 no.2
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• pp.108-111
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• 2010

New salens (3) and their Cobalt complexes (4) were prepared from meso-1,2-bis(ortho-hydroxyphenyl)-1,2-diaminoethane (1) and substituted salicylic aldehydes (2). In contrast to symmetric structure of salen ligand (3), salen-Co(III) complexes (4) showed dissymmetric molecular structure due to participation of three hydroxyl groups in complex formation. One of the salens (3b) revealed decrease in Cyclin D1 expression, which represents anti-cancer property.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.2
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• pp.11-20
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• 2002

In this paper, for many prime power q, it is shown that new cyclic relative difference sets with parameters (equation omitted) can be constructed by using d-homogeneous functions on $F_{q^{n}}${0} over $F_{q}$ with difference-balanced property, where $F_{q^{n} }$ is a finite field with $q^{n}$ elements. Several new cyclic relative difference sets with parameters (equation omitted) are constructed by using p-ary sequences of period $q^{n}$ -1 with ideal autocorrelation property introduced by Helleseth and Gong and d-form sequences.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.9
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• pp.663-670
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• 2020

A study on mechanical property characterization and modeling technique was carried out to approximate the behaviour of structures with 2.5D C/SiC material. Several tensile tests were performed to analyze the behaviour characteristics of the 2.5D C/SiC material and elastic property was characterized by applying a mathematical homogenization and a modified rule of mixture. SiC matrix representing the elasto-plastic behavior approximates as a bilinear function. Then the equivalent yield strength and equivalent plastic stiffness were calculated by minimizing errors in experiment and approximation. RVE(Representative Volume Element)was defined from the fiber and matrix configuration of 2.5D C/SiC and a process of calculating the effective stiffness matrix by applying the modified rule of mixture to RVE was implemented in the ABAQUS User-defined subroutine. Finite element analysis was performed by applying the mechanical properties of fiber and matrix calculated based on the proposed process, and the results were in good agreement with the experimental results.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1262-1263
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• 2011

Sulfur hexafluoride is the most commly used insulation gas in electrical systems. Gas insulated systems are widely used in the electric power industry for transmission and distribution of electrical energy. When $SF_6$ was first discovered, the potential application was only considered for insulation because of good dielectric properties. But the widespread use of $SF_6$ gas by electric power and other industries has led to increase concentrations of $SF_6$ gas in the atmosphere. This concern as to possible effects on global warming because $SF_6$ is a potent greenhouse gas. That's why firstly we studied uniform and nonuniform field property by mixing $SF_6$ and N2 gas. This paper presents the dielectric strength and insulating property for particle contamination under $SF_6/N_2$ mixtures. Two types of mixed gases(50% $SF_6$_50%$N_2$, 20% $SF_6$_80%$N_2$) were applied. We performed tests for the length and shape of particle. Test gas pressure is from 0.3 to 0.7 Mpa. The study was conducted to develop environment-friendly insulating material for GIS that can reduce $SF_6$ gas and make a design criteria for mixtures.

• Journal of Technology Innovation
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• v.14 no.3
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• pp.43-69
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• 2006

In this study, we examine the effect of TRIPS on the relationship between R&D expenditures and patent applications in manufacturing firms. The first set of tests examines the association between patent applications and R&D expenditures and firm specific factors such as firm size and capital intensity. The next set of tests adds environmental factors including R&D intensity of the industry and development of TRIPS. We divide the sample period into three subperiods according to the progress of TRIPS subperiod 1(1984-1988) before TRIPS, subperiod 2(1989-1994) after negotiation of TRIPS and subperiod 3(1995-2000) after agreement on TRIPS. Regression model reveals that the coefficient on firm size is significantly positive over the all sample Period, while that of R&D expenditures of R&D intensive firms is significantly positive in subperiod 2 and 3(1989-2000) and that of capital intensity is significantly negative only in subperiod 3(1995-2000). The findings suggest that the efficient intellectual property system promotes the patent application of R&D intensive firms.

• Journal of the Korean Mathematical Society
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• v.59 no.2
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• pp.337-352
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• 2022

We consider the set of points with historic behavior (which is also called the irregular set) for continuous flows and suspension flows. In this paper under the hypothesis that (X_t)_t is a continuous flow on a d-dimensional Riemaniann closed manifold M (d ≥ 2) with gluing orbit property, we prove that the set of points with historic behavior in a compact and invariant subset ∆ of M is either empty or is a Baire residual subset on ∆. We also prove that the set of points with historic behavior of a suspension flows over a homeomorphism satisfyng the gluing orbit property is either empty or Baire residual and carries full topological entropy.

• Journal of Digital Contents Society
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• v.16 no.5
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• pp.835-847
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• 2015

Photo scanning can create point cloud and polygon models like 3D scanners bringing an object into the 3 dimensional world by combining several sheets of photographic information. The created data give us information about planes and sectional forms required for a 2 dimensional survey as well as 3 dimensional figures of buried cultural property. It requires a lot of time to record buried cultural property in the field, however, the photo scanning technique does not need additional equipment and manpower so the work may begin immediately while the property is protected. Moreover, it reduces financial burdens as it creates 3 dimensional data using images acquired by photography but provides the optimal condition to check 3 dimensional information quickly and easily.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.126-129
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• 1999

Dielectric and piezoelectric properties of perovskite materials such as La modified $Pb(Zr,Ti)O_3$ ceramics and $Pb(Zn_{1/3}Nb_{2/3})O_3-PbTiO_3$ single crystals were investigated for cryogenic capacitor and actuator applications. Enhanced extrinsic contributions resulted in piezoelectric coefficient (d33) as high as 250 pC/N at 30 K, superior to that of PZT ($d_{33}$ ~ 100 pC/N). This cryogenic property enhancement was associated with retuning the MPB (or cryogenic temperatures. PZN-PT single crystals exhibited dramatic property improvements such as $d_{33}$ > 500 pC/N at 30 K as a result of an engineered domain state.