• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.164-166
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• 2013

Using a simple random walk model, this study simulated the growth of a self-assembled monolayer (SAM) pattern generated by dip-pen nanolithography (DPN). In this model, the SAM pattern grew mainly via the serial pushing of molecules deposited from the tip. This study examined various SAM patterns, such as lines, crosses and letters, by changing the tip scan speed.

• Journal of Information Technology Applications and Management
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• 제23권2호
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• pp.29-59
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• 2016

These days, the business environment such as Information Technology (IT) is rapidly changing, and organizations are consistently trying to change themselves for the survival and success under the changing environment. In this situation, change management is very important because it draws the change behaviors of organization members for the success of organizational change. The purpose of this study is to investigate the effect of the organization members' psychological factors on the performance of the acquisition of new IT, which is one of the most important organizational change. Based on previous studies in the area of organizational change, organization members' resistance to change, self-congruity theory, change activities and organizational performance, the research model is developed for validating the effect of organization members' self-congruity on the performance of the acquisition of new IT. Statistical analyses show that self-congruity has a significant effect on the change activities. In particular, private self-congruity has more impact on the change activities than public self-congruity. In addition, self-leadership, rewards and recognitions, and the diffusion of change activities have significant effects on job satisfaction. Self-leadership has a significant effect on organizational commitment.

• 대한기계학회논문집
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• 제18권5호
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• pp.1253-1263
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• 1994

The experimental study is carried out to identify the combustion generated noise mechanism in free turbulent jet diffusion flames. Axial mean fluctuating velocities in cold and reacting flow fields were measured using hot-wire anemometer and LDv.The overall sound pressure level and their spectral distribution in far field with and without combustion were also measured in an anechoic chamber. The axial mean velocity is 10-25% faster and turbulent intensities are about 10 to 15% smaller near active reacting zone than those in nonreacting flow fields. And sound pressure level is about 10-20% higher in reacting flow fields. It is also shown that the spectra of the combustion noise has lower frequency characteristics over a broadband spectrum. These results indicate that the combustion noise characteristics in jet diffusion flames are dominated by energy containing large scale eddies and the combusting flow field itself. Scaling laws correlating the gas velocity and heat of combustion show that the acoustic power of the combustion noise is linearly proportional to the 3.8th power of the mean axial velocity rather than 8th power in nonreacting flow fields, and the SPL increases linearly with logarithmic 1/2th power of the heat of combustion.

• 열처리공학회지
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• 제6권1호
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• pp.9-16
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• 1993

To investigate the properties of diffusion bonding of 7050 Al alloy, the diffusion bonding joints have been produced in self-made diffusion bonding hot-press which admits a defined application of the bonding pressure during the heating phase and also rapid cooling after the bonding process with various bonding condition. The strength of the bond increases with increasing the bonding time and temperature. Shear test at toom temperature showed that high strength up to 70% that of parent metal (320 MPa), 220 MPa for the specimen bonded 14 hr at $560^{\circ}C$, with 3 MPa. In this case, however, there is large deformation more than 20% reduction in thickness. The results were correlated with joint characteristics found by optical microstructure and by fractography by SEM. When the strengths of the bonds are more than 50% that of parent metal, a great deal of dimples stretched along the direction of shear stress are observed over the fractured surface of the bond. On the microstructure of the bond line, initial mophology of the bond line disapeared for the grain boundary migration with increasing the bonding time.

• 한국컴퓨터정보학회논문지
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• 제14권7호
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• pp.97-103
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• 2009

본 논문의 무선 센서네트워크에서 사용할 수 있는 효율적인 라우팅 방법인 MP-DD (MultiPath-Direct Diffusion) 알고리즘을 제안한다. 기존의 DD(Directed Diffusion)에서는 하나의 경로만을 강화하여 사용하는 것과 달리 제안한 알고리즘은 다중 경로를 강화하면서, 해당 경로에 높여 있는 센서 노드의 남은 에너지 등급을 고려하여 에너지 레벨이 높은 경로에 따라 가중치를 부여하고, 몇 개의 다중경로를 이용하여 사용함으로써 에너지 소모를 감소시키고 동시에 네트워크에 전체적으로 에너지를 골고루 사용하게 할 수 있다. 시뮬레이션 결과에서는 이러한 센서 네트워크를 위한 단순한 라우팅 방법의 가능성을 증명하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제15권2호
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• pp.79-87
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• 2011

본 연구에서는 초기 균열을 도입한 철근콘크리트 부재에 대한 침지 염화물 침투 실험을 수행하였다. 염화물 확산 특성과 임계 균열폭을 비교하였으며, 콘크리트 자기복원 특성을 검토하였다. 실험결과에 따르면, 표면 균열폭이 증가할수록 염화물 침투저항성이 크게 감소하였으며, 광물질 혼화재를 사용할 경우, 비균열 부재의 염화물 침투저항성은 크게 개선되었지만, 고로슬래그 및 플라이애쉬 혼화재를 사용할 경우에 균열이 발생하게 되면 도리어 염화물 침투저항성은 보통 콘크리트에 비해 크게 저하하였다. 임계 균열폭은 침지 염화물 침투 실험 결과 평균 $29{\mu}m$으로 측정되었다. 자기복원 현상에 의해 $4{\sim}15{\mu}m$ 범위의 균열이 복원되었다. 그러나 콘크리트 자기복원 현상에 의해 시각적으로 복원된 부분의 염화물 침투 저항성은 완전히 회복되지 않았다.

• 한국재료학회지
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• 제17권9호
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• pp.469-474
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• 2007

Electroless deposition(ELD) was applied to fabricate Cu interconnections on a TaN diffusion barrier with Pd seed layer. The Pd seed layer was obtained by self-assembled monolayer method(SAM) with PDDA and PSS as surfactants. We were able to obtain about 10nm Pd nano particles as seeds for electroless Cu deposition and the density of Pd seeds was much higher than that of Pd seeds fabricated by conventional Pd sensitization-activation method. Also we were able to obtain finer Cu interconnections by ELD. Therefore we concluded that the Pd seed layer by SAM was able to be applied to form Cu interconnection by ELD for under 30nm feature.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2002년도 춘계총회 및 학술발표회
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• pp.39-39
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• 2002

• 한국자기공명학회:학술대회논문집
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• 한국자기공명학회 2002년도 제20회 학술발표회
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• pp.13-13
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• 2002

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.368-371
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• 2006

[ $La_{0.8}Sr_{0.2}Co_{1-x}Mn_xO_3$ ] cathode as a high performance cathode on YSZ electrolyte was studied by analyzing impedance spectra. It was shown that cathode property of $La_{0.8}Sr_{0.2}Co_{1-x}Mn_xO_3$ is bet ter than that of$La_{0.8}Sr_{0.2}CoO_3$. At $700^{\circ}C$ in air environment, $La_{0.8}Sr_{0.2}Co_{0.4}Mn_{0.6}O_3$ cathode on CGO- layered YSZ electrolyte showed very low area specific resistance of $0.14{\Omega}cm^2$, which is low enough for intermediate-temperature sol id oxide fuel cells. This is because material properties of ionic conductivity and thermal expansion compatibility with electrolyte were optimized. Judging from activation energy and oxygen part i al pressure dependance of cathode property, it was noted that oxygen surface exchange kinetics is dominantly influential on cathode property in higher temperature region than $700^{\circ}C$ and oxygen self-diffusion in cathode material is more influential in lower temperature region.