• 한국해양학회지:바다
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• 제6권1호
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• pp.1-12
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• 2001

Topex/Poseidon(T/P)고도계 자료를 조석 수치 모델에 혼합하여 북동 아시아 해역의 $M_2,\;S_2,\; K_1$, 및 $O_1$ 분조를 $5'{\times}5'$ 분해능으로 계산하여, 북동 아시아의 조석을 산정하였다. Blending 방법에 사용되는 가중 인자 값에 대한 모델반응을 검토하기 위해 $M_2$ 분조만을 고려한 수치 실험이 수행되었으며, 수치 실험을 통해 T/P 자료를 정확히 재현하되 혼합함으로써 발생하는 잡음을 줄이기 위해 가중 인자 값은 수심의 평방근에 반비례하도록 설정하였다. T/P자료에서 구한 $M_2,\;S_2,\; K_1$, 및 $O_1$ 분조를 동시에 혼합한 수치 모델 결과는 연구 해역 내의 모든 T/P궤도 자료와 비교되었다. 진폭 오차와 지각 오차의 평균은 거의 0으로 나타났다. 진폭 오차의 표준 편차는 2 cm 내외였으며, 지각오차의 표준 편차는 $10^{\circ}$보다 작았다. T/P자료를 혼합한 모델 결과는 특히 얕은 수심(h<250m)의 T/P 궤도 자료와 거의 일치하는 것으로 나타났다. 그러나 T/P 자료만으로부터 계산된 진폭과 지각은 깊은 수심 해역에 대해서는 불합리한 공간 변화를 보이는 반면, 이들 자료를 동화시킨 모델 결과는 T/P 자료와는 차이를 보이나 합리적인 진폭과 지각의 공간 분포를 보였다. 한편 T/P자료를 혼합한 모델 결과는 자료 동화에 사용하지 않은 연안 관측 자료와도 비교적 잘 일치하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.448-453
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• 2003

In this study, the effects of oxygen component in fuel and exhaust gas recirculation(EGR) method on the exhaust emissions has been investigated for a D.I. diesel engine. It was tested to estimate change of exhaust emission characteristics for the commercial diesel fuel and oxygenate blended fuel which has five kinds of blending ratio. Dimethoxy methane(DMM) contains oxygen component 42.5% in itself. and it is a kind of effective oxygenated fuel for reduction of smoke emission. It was affirmed that smoke emission was decreased with increasing of DMM blending ratio. But, NOx emission was increased compared with commercial diesel fuel. It was needed a NOx reduction countermeasure that EGR method was used as a countermeasure for NOx reduction. It was found that simultaneous reduction of smoke and NOx emission was achieved with DMM blended fuel and cooled EGR method($10{\sim}15%$).

• 펄프종이기술
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• 제33권2호
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• pp.24-31
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• 2001

As a novel method to improve strength properties of recycled test liner, Condebelt press drying system was introduced and adopted into Korea. New press drying treatment could enhance the surface and strength properties in accordance with the increase of sheet density. However, Condebelt drying can not increase the density of repeatedly recycled test liner as much as that of virgin UKP and at the same density condition, the strength of Condebelt press dried UKP is greater than that of press dried test liner. In order to increase the strength of test liner, two attempts were tried in this study. First, addition of polyelectrolytes, dry strength agent was investigated with a view to promote the fiber bonding potential of reclaimed corrugated container pulp. Second, blending effect of fines were analyzed in an aims of increasing density and strength of test liner. The results were as follows; Even in the case of test liner densified by Condebelt press dryer, addition of amphoteric PAM as a dry strength agent was effective in increasing strength properties and so the effect of dry strength agent on improving bonding potential of recycled OCC fiber could be confirmed. As an appropriate addition level of amphoteric PAM, below 1% based on dry pulp weight was suggested. Different from virgin UKP, density of recycled test liner can be increased by the blending of OCC fines and strength properties also can be improved. However, excessive blending of OCC fines could result in decreasing of density and serious weakening of test liner. The best blending ration of fines in test liner can be determined as about 30%. Taking into account the fines content in general OCC pulp as 50%, excessive 20% of fines were supposed to be fractionated and removed in order to achieve the best strength of Condebelt press dried test liner.

• 대한전자공학회논문지SP
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• 제41권5호
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• pp.175-183
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• 2004

본 논문은 적외선 파장대의 벽화 밑그림영상과 가시광선 파장대의 패턴영상을 이용한 다중영상 정합 기법과 적응적 중첩영역 병합 기법을 이용하여 고해상도 적외선 벽화 밑그림 영상을 생성하기위한 영상 모자익 기법을 제안한다. 기존의 영상 모자익 기법은 특징이 없는 대상에 대해서 정합을 적용하기가 힘들었다 그리고 중첩영역의 크기에 따라 정합과 병합의 오차가 상반되는 현상이 발생한다. 이러한 문제를 해결하기 위해 본 논문에서는 첫 번째로, 영상에서 주목할 만한 특징이 없는 경우에도 프론젝터를 사용하여 패턴영상을 획득하고 의사 칼라 영상을 획득하여 정합을 가능하게 하였다. 두 번째, 인접한 영상간의 최소 병합 오차를 가지는 중첩영역을 찾아서 그 영역에 대해서만 병합을 수행함으로서 흐림현상을 해결하였다. 결과적으로 제안한 방법이 기존의 모자익 방법보다 더 효과적이고 효율적인 것을 확인하였고, 또한 적외선 벽화 밑그림 영상의 모자익에 더 적당한 것을 확인하였다. 실험 결과는 이 알고리듬의 강건함과 정확성을 보여준다.

• 대한지구과학교육학회지
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• 제8권1호
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• pp.1-11
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• 2015

The purpose of this study was to find out about the awareness and demands of pre-service and in-service elementary school teachers on STEAM education. For the purpose of this study, researcher administered survey questionnaires were conducted for 160 pre-service teachers and 191 in-service teachers who were sampled by convenience sampling method. The results were as follows. On the awareness and demand for knowledge and necessity on STEAM, first, on the understanding related knowledge, most respondents have heard of STEAM education(97.7%), and well aware of STEAM(91.4%) through the teacher training course(80.3%). Second, on the necessity, 60.4% respondents were located in "very necessary" and "necessary" entry. On the awareness and demand for applying STEAM, first, on the reasons of applying STEAM was to help the cognitive and affective development. Also 67.3% respondents would like to apply STEAM on their science class. The reason was necessity on STEAM, and the most suitable subject for blending with science of applying to STEAM was technology, on the other hand the most difficult subject was art. Second, on the effect of STEAM, most respondents had positive awareness on the all categories. Third, on the purpose of science education, also had positive awareness on the all categories of the purpose of science education. On the awareness and demand for blending ways of STEAM and improvements, first, on the blending ways of STEAM, topic centered blending related to real life had a majority. Second, on the improvements, to improve the STEAM education, many respondents pointed out the development of teaching and learning STEAM program and dissemination of related resources.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2008년도 춘계 종합학술대회 논문집
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• pp.648-652
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• 2008

*.x 확장자는 3D 모델개발자와 3D프로그래머들이 프로그램을 보다 쉽게 개발하기 위해서 주로 사용된다. 오늘날에는 3D프로그래밍을 위한 하드웨어들의 성능이 많이 개선되었지만, 아직도 효율적인 애니메이션 생성을 위한 방법들에 관한 연구는 계속 진행되고 있다. 특히 3D 모델개발자들은 *.x 파일을 이용하여 골격애니메이션을 만들 때 한 부분의 에러가 다른 부분으로 전이되어 찌그러지는 현상이 나타날 수 있기 때문에 에러를 수정하는데 많은 시간이 필요로 하는 문제점을 내포하고 있다. 그래서 이와 같은 문제점을 해결하기 위해서 본 논문에서는 여러 개의 골격애니메이션을 블랜딩 할 수 있는 방법을 제안하였다. 이를 위해서 3D Max, Maya와 같은 애니메이션 블랜딩을 위한 프로그램이나 *.x 파일을 코딩하여 사용하고 있고, 골격 애니메이션을 합성하는 특수효과를 3D Max8.0을 사용하여 *.x 파일로 구현하였다.

• Journal of applied mathematics & informatics
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• 제32권5_6호
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• pp.761-781
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• 2014

An exponentially accurate nonconforming spectral element method for elasticity systems with discontinuities in the coefficients and the flux across the interface is proposed in this paper. The method is least-squares spectral element method. The jump in the flux across the interface is incorporated (in appropriate Sobolev norm) in the functional to be minimized. The interface is resolved exactly using blending elements. The solution is obtained by the preconditioned conjugate gradient method. The numerical solution for different examples with discontinuous coefficients and non-homogeneous jump in the flux across the interface are presented to show the efficiency of the proposed method.

• Korea-Australia Rheology Journal
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• 제15권1호
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• pp.43-50
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• 2003

In this study, two types of biodegradable resins-based clay nanocomposites, in which organic montmorillonite clay was filled, were prepared by the direct melt blending method. In order to characterize the nanocomposite structure, wide-angle X-ray diffraction (WAXD) and TEM observation were performed. Characterization of the nanocomposites shows that intercalated and partially exfoliated structures were generated by the melt blending method. Mechanical and rheological properties of the nanocomposites were measured respectively. For the mechanical properties, there were improvements in tensile strength and Young's modulus of the nanocomposites due to the reinforcement of nanoparticles. The rheological behaviors of the nanocomposites were significantly affected by the degree of the dispersion of the organoclay. The storage modulus of the nanocomposites was measured and the degree of the dispersion of the organoclay was evaluated from the value of the terminal slope of the storage modulus. In addition, the quantity of the shear necessary for making the nanocomposite for melt intercalation method was estimated from the relationship between the value of the terminal slope of the storage modulus and the applied shear.

• 대한기계학회논문집B
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• 제30권4호
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• pp.358-363
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• 2006

In this study, the effects of oxygenated fuel such as ethylene glycol mono-normal butyl ether(EGBE) was investigated both DI and IDI diesel engine. Because EGBE includes oxygen content approximately 27.1 %, it is a kind of oxygenated fuel that the smoke emission of EGBE blending fuel is reduced remarkably compared with commercial diesel fuel. The focus of this study was to investigate the effects of the addition of oxygenated fuel to diesel fuel on the engine-out emissions and the performance. Smoke emissions of all EGBE blends were reduced substantially in comparison with conventional diesel fuel. This study showed that remarkable reduction of smoke with oxygenate blending fuels in diesel engines including DI and IDI combustion method. Besides, this study showed that simultaneous reduction of smoke and NOx emissions could be achieved by oxygenated fuel and EGR method that was applied to decrease NOx emissions increasing with smoke emissions reduction.

• 한국산림과학회지
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• 제76권2호
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• pp.119-126
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• 1987

본 연구는 활엽수재(闊葉樹材)인 층층나무(Cornus Controversa Hemsl), 굴참나무(Quercus variabilis Blume) 및 산벚나무(Prunus sargentii Redher)를 시험편(試驗片)으로 하여 치수안정화효과(安定化效果)를 높일 수 있는 PEG 적정분자량(分子量)과 혼합방법(混合方法)을 혼합비 I, II, III, IV 및 V 중에서 찾는데 그 목적이 있었으며 실험결과는 다음과 같았다. 1. 목재내(木材內) PEG 주입율(注入率)은 비중에 따른 영향을 받았으며 굴참나무를 제외하고 만족할만한 주입율을 나타내어 적정혼합방법은 PEG V임을 알았다. 2. PEG V용액에서의 팽윤효과(澎潤效果)는 층층나무, 산벚나무에서 높았으며, 굴참나무의 팽윤효과(澎潤效果)를 높이기 위해서는 방수성약제(防水性藥劑)의 도장(塗裝)이 필요하다. 3. PEG V용액에서 산벚나무가 82.59%로 가장 높은 항수축능(抗收縮能)을 보였고 굴참나무가 62.79%로 가장 낮은 값을 보여 주었다. 4. 활엽수재(闊葉樹材)의 치수안정화(安定化)는 PEG의 혼합방법에 따라 커다란 차이를 나타내지 않았다. 5. 이상과 같은 실험결과를 종합 분석한 결과 비중이 높은 활엽수재(闊葉樹材)의 경우에는 PEG-400과 PEG-1000으로 혼합하되 외부인자를 충분히 고려할 필요가 있다.