• 소음진동
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• 제10권3호
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• pp.423-429
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• 2000

This paper investigates the use of boundary element method(BEM) to analyze the insertion loss of a noise barrier. To begin with the validity of the BEm for the analysis of noise barrier insertion loss in checked by both Lam's theoretical method and the measurements in the anechoic chamber for the scale-down models. Through simulation it is shown that using 2D BEM model is sufficient to the analysis for the barrier with large ratio of length to height. By using 2D BEM model the insertion loses are predicted for the real noise barriers in several cases which are the case that they are built parallel on both roadsides the one that there are multiple sound sources and the one that there is a gap between a concrete structure and a barrier plate.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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• pp.281-286
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• 2005

To understand fundamental characteristics of combustion in a small scale device, the effects of the momentum and heat loss on the stability of laminar premixed flames in a narrow channel are investigated by two-dimensional high-fidelity numerical simulation. A general finding is that momentum loss promotes the Saffman-Taylor (S-T) instability which is additive to the Darrieus-Landau (D-L) instabilities, while the heat loss effects result in an enhancement of the diffusive-thermal (D-T) instability. These effects are also valid in nonlinear behavior of the premixed flame. The simulations of multiple cell interactions are also conducted with heat and momentum loss effects.

• 경영과정보연구
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• 제21권
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• pp.239-269
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• 2007

The purpose of this thesis is to analyze empirically the relationship between market structure, measured by Herfindahl-Hershmann Index(HHI), and financial factors, and innovation in Korean industry panel datasets for 2000-2006. Results show that debt ratio and scale of the firm has a consistent positive effect on the investment in research and development. As more scale of the firm is getting bigger, the investment in R&D decrease. Also, as more debt ratio of firm rise, the investment for innovation increase. Concentration ratio, the HHI and the classification factor of High-tech industry and Low-tech industry has a consistent positive effect on the innovation. Factors affecting the investment in research and development include market structure and characteristics of industry as well as the internal affairs of the firm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2006년도 하계종합학술대회
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• pp.755-756
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• 2006

In this paper, We design the high performance 2D product Iterative decoder using three different external value design. We improved the external value operation in two ways to reduce the delay and speed. In this proposed operation, each design has been simulated on Matlab and MaxPlusII, and implemented on the FPGA to measure their performance.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1819-1824
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• 2004

The common method to improve heat transfer in Nuclear fuel rod bundle is install a mixing vane in space grid. The previous split mixing vane is guides cooling water to swirl flow in sub-channel of fuel assembly. But, this swirl flow decade rapidly after mixing vane and the effect of enhancing the heat transfer vanish behind this short region. The large scale secondary vortex flow was generated by rearranging the inclined angle direction of mixing vanes to the coordinated directions. This LSVF mixing vanes generate the most strong secondary flow vortices which maintain about 35 $D_H$ after the spacer grid and the streamwise vorticity in subchannel with LSVF mixing vane sustain two times more than that in subchannel with split mixing vane. The turbulent kinetic energy and the Reynolds stresses generated by the mixing vanes have nearly same scales but maintain twice more than previous type.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.109-110
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• 2008

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.132-132
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• 1998

Ion bombardment in the keV range is known to induce drastic chemical modifications in organic and inoranic molecular comppounds. A degrading effects in orgainc materials such as the release of ppolymer compponents and the chemistry of the iradiation pprocess have been observed. The work to be described was carried out in order to understand the irradiation effect better. The sampple(ppolyimide : Kappton ) Were irradiated by Ar+, Ne+, H+ ions and electrons (3 keV) to fluence ranging from ~1$\times$1015 to ~1$\times$1017 ions/$cm^2$ at room tempperature. The impplant was usually rastered over an area of a few $cm^2$ . These ion impplantation were carried out in an electron sppectrometer ESCA 5700 (ppHI Ltd) at a residual gas ppressure of ~5$\times$10-10 Torr. X-ray pphotoelectron sppectroscoppy(XppS) measurements were made using a monochromatized Al Kａ(1486.6 eV) excitation source. The pphotoemitted electrons were detected by hemisppherical analyser with a ppass energy of 23.5 eV. Core-level binding energies were referenced to the Fermi level. To avoid the charging effect it was used the neutralizer. We studied the irradiation effects on ppolyimide with Ar+, Ne+, He+ ions and electrons by XppS which 추 pprovide detailed information concerning the bonding-induced changes.

• 한국진공학회지
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• 제7권s1호
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• pp.57-77
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• 1998

Heteroepitaxial $Y_2O_3$ films were grown on a Si(111) substrate by ionized cluster beam deposition(ICBD) in ultra high vacuum, and its qualities such as crystllitnity, film stress, and morphological characteristics were investigated using the various measurement methods. The crystallinity was investigated by x-ray diffraction (XRD) and reflection high energy electron diffraction (RHEED). Interface crystallinity was also examined by Rutherford backscattering spectroscopy(RBS) channeling, transmission electron microscopy(TEM). The stress of the films was measured by RBS channeling and XRD. Surface and interface morphological characteristics were investigated by atomic force microscopy (AFM) and x-ray scattering method. Comparing the interface with the surface characteristics, we can conclude that many defects at the interface region were generated by interface reaction between the yttrium metal and SiO2 layer and by ion beam characteristic such as shallow implantation, so that they influenced the film qualities. The film quality was dominantly depended on the characteristic temperature range. In the temperature range from $500^{\circ}C$ to $600^{\circ}C$, the crystallinity was mainly improved and the surface roughness was drastically decreased. On the other hand, in the temperature range from $600^{\circ}C$ to $700^{\circ}C$, the compressive stress and film density were dominantly increased, and the island size was more decreased. Also the surface morphological shape was transformed from elliptical shape to triangular. The film stress existed dominantly at the interface region due to the defects generation.

• 정신신체의학
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• 제11권1호
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• pp.60-68
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• 2003

연구목적: 본 연구는 Richard D. Lane이 인지발달이론에 기초하여 감정의 경험을 평가하기 위해 개발한 Levels of Emotional Awareness Scale(LEAS)를 번역하고 그 타당도와 신뢰도를 검증하여 한국판 감정자각 수준 척도(LEAS-K)를 개발하고자 하는데 목적이 있다. 방 법: LEAS를 일차번역과 역번역의 과정을 거쳐 가능한 원문에 가깝게 번역을 한 후 문화적 차이를 고려하여 수정한 것을 최종 연구 자료로 사용하였다. 경북대학교 의예과와 의학과에 재학 중인 학생 476명(남자 322명, 여자 154명)을 대상으로 검사를 시행하여 신뢰도를 알아보았으며 타당도를 검사하기 위해 한국판 감정표현불능증 척도(TAS-20K), 개방성 척도(Openness to Experience Inventory), 사회 바람직성 척도(Marlowe-Crowne Scale), 외현 불안 척도(Bendig short form of the Taylor Manifest Anxiety Scale), 정서 표현성 척도(Emotional Expressivity Scale)를 같이 시행하였다. 결 과: LEAS-K의 내적 일치도(internal consistency)는 Cronbach's alpha 계수 0.81이었으며 검사자간 신뢰도는 0.99였다. LEAS-K와 TAS-20K는 부적 상관관계(r=-0.10), 개방성 척도, 사회 바람직성 척도와는 정적 상관관계(r=0.10)가 있었으며 통계적으로 모두 유의하였다. 외현 불안 척도, 정서 표현성 척도와는 통계적으로 유의한 상관관계가 없었다. 결 론: LEAS-K는 신뢰도와 타당도가 만족할 만한 수준임을 알 수 있었고 감정을 경험하는데 있어서 감정의 강도보다는 감정 경험의 구조(structure)나 복합성(complexity)을 측정하는 척도임을 시사하였다.

• 기술혁신연구
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• 제21권2호
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• pp.137-167
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• 2013

본 논문은 정부의 R&D 투자를 위한 재정지출의 확대가 민간기업의 연구개발 투자의 확대에 어떠한 영향을 미치며, R&D 투자 확대를 위한 대학과 기업의 지출 간의 관계에서 어떠한 관계가 확인되는지를 추정하고 있다. 본 논문의 추정결과를 통해 얻을 수 있는 결론은 다음과 같다. 첫째, R&D 투자확대를 위한 정부의 재정지출 확대는 민간기업의 R&D 투자를 확대시킨다. 그러나 대학 등의 고등교육기관의 지출 확대는 오히려 민간기업의 투자를 위축시킨다. 둘째, 대학의 R&D 투자의 확대가 민간기업의 R&D 투자를 구축하는 효과는 강하게 나타나고 있으며, 이러한 구축효과는 각 국가의 경제력, 재정상황, 그리고 경기변동 등 구조적인 변화에 강하게 영향을 받는다. 셋째, R&D 투자를 위한 정부지출이 대학과 기업 중에서 대학에 더 집중될수록 대학과 기업 간의 비대칭적인 관계는 강하게 나타나며, 이러한 관계에는 대학의 투자재원 중 기업부분으로부터의 투자재원이 큰 영향을 미친다. 넷째, 비록, R&D 투자의 확대를 위한 정부의 보조금 규모가 커질수록 기업의 R&D 투자가 확대되고 대학과 기업의 비대칭적인 관계가 개선된다고 하더라도, 정부의 보조금을 통해서 이러한 문제들을 전적으로 해결하기는 사실 상 어렵다.