• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2002년도 춘계학술대회논문집
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• pp.239-242
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• 2002

멀티미디어 환경에서 많은 패킷 스위치 네트워크로부터 발생되는 트래픽은 burstiness성질이 상당히 넓은 범위의 time scale상에 존재하고, 트래픽 특성이 self-similar현상을 보이고 있다는 것이 알려지고 있다. 본 논문에서는 Shared-Buffer를 이용한 ATM 스위치 buffer관리방법을 적용하여 입력포트에 self-similar 트래픽이 들어올 때 출력포트의 long-range dependency의 변화를 분석하며 아울러 큐잉 지연, 셀 손실률 그리고 이용도(utilization)등이 self-similar 트래픽에 미치는 영향을 분석할 것이다.

• The Korean Journal of Ceramics
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• 제3권3호
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• pp.163-168
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• 1997

Most of heteroepitaxial $\beta$-SiC thin films have been successfully grown on Si(100) adapting a carburizing process, by which a few atomic layers of substrate surface is chemically converted to very thin SiC layer using hydrocarbon gas sources. Using an organo-silicon precursor, bis-trimethylsilymethane (BTMSM, [$C_7H_{20}Si_2$]), heteropitaxial $\beta$-SiC thin films were successfully grown directy on Si substrate without a carburized buffer layer. The defect density of the $\beta$-SiC thin films deposited without a carburized layer was as low as that of $\beta$-SiC films deposited on carburized buffer layer. In addition, void density was also reduced by the formation of self-buffer layer using BTMSM instead of carburized buffer layer. It seems to be mainly due to the characteristic bonding structure of BTMSM, in which Si-C was bonded alternately and tetrahedrally (SiC$_4$).

• 한국통신학회논문지
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• 제30권4B호
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• pp.162-169
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• 2005

패킷 스위치로부터 발생되는 트래픽이 전통적인 트래픽 모델인 포와송 분포와 마코비안 프로세스로 가정된 네트워크로부터 발생되는 트래픽과 상당히 차이가 나는 self-similar 현상을 보이고 있다는 것이 알려지고 있고 또한 기존에 제안된 대부분의 호 수락 제어 방법에 대한 성능 분석은 스위치가 단독으로 존재한다고 가정하여 이루어지고 있다. 그러나 실제 트래픽이 목적지에 도달하기 위해서는 라우팅을 통하여 여러 스위치들을 거쳐야하므로 호 수락 제어 방법에 대한 성능 분석은 다단으로 연결된 스위치로 확장되는 것이 필요하다. 본 논문을 통하여 기존에 제안된 호 수락 제어 방법이 단일 스위치 환경 하에서는 적절하게 동작이 이루어지나 다단으로 스위치가 연결되어 있는 환경에서는 뒤에 위치하고 있는 스위치에 필요 이상의 유효 대역폭을 할당 한다는 것을 알 수 있다. 그러므로 본 논문에서는 공유 버퍼 메모리를 갖는 다단 네트워크 스위치 환경에서 셀 손실률과 이용률 그리고 각 스위치 출력포트의 self-similarity를 분석하여 self-similar 트래픽 환경에서 효과적으로 대역폭을 할당할 수 있는 호 수락 제어 방법을 제안한다.

• BioChip Journal
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• 제12권4호
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• pp.317-325
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• 2018

This paper investigated the effects of ionic strength in the medium on a preconcentrator for a protein sample with low concentration. The preconcentration chip was designed and fabricated using a polydimethylsiloxane replica through standard lithophotography. A glass substrate is silanized prior to functionalizing the nanoparticles for self-assembly at a designed region. Due to the overlap of electrical double layers in a nanofluidic channel, a concentration polarization effect can be achieved using an electric field. A nonlinear electrokinetic flow is induced, resulting in the fast accumulation of proteins in front of the induced ionic depletion zone, so called exclusion-enrichment effect. Thus, the protein sample can be driven by electroosmotic flow and accumulated at a specific location. The chip is used to collect fluorescein isothiocyanate-labeled bovine serum albumin (FITC-BSA) diluted in phosphate-buffered saline (PBS) buffer solution. Different concentrations of the buffer media were studied herein. Fluorescence intensity images show that the buffer concentration of 4 mM is more appropriate than all the other ones. The sample of FITC-BSA with an initial concentration of $10{\mu}M$ in the 4 mM PBS solution increases its concentration at the desired region by up to 50 times within 30 min, demonstrating the results in this investigation.

• 대한산업공학회지
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• 제41권4호
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• pp.330-337
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• 2015

A bucket-brigade is a way of transporting items where items are passed from one person to the next. The operation of the bucket brigade imitates the cooperative behavior of ants when brood, food or other resources are moved. Koo (2009) presented a bucket brigade-based assembly cell where each worker follows a simple rule: perform assembly operations on a product until the next worker downstream takes it over; then go back to the previous worker upstream to take over a new assembly job. In this way, the flow line is self-balanced without any predetermined job assignment. However, there are some productivity losses related to hand-off and blocking. This paper examines the hand-off and blocking losses and presents a new bucket brigade-based assembly cell where working areas for each assembler is restricted with the help of buffer interfaces. Simulation experiments are used to validate the performance of the new assembly system.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.236-244
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• 2005

Radioactive wastes arising from a wide range of human activities are in many different physical and chemical forms, contaminated with varying radioactivity. Their common feature is the potential hazard associated with their radioactivity and the need to manage them in such a way as to protect the human environment. The geological disposal is regarded as the most reasonable and effective way to safely disposal high-level radioactive wastes in the world. The conceptual model of geological disposal in China is based on a multi-barrier system that combines an isolating geological environment with an engineered barrier system. The buffer is one of the main engineered barriers for HLW repository. The buffer material is expected to maintain its low water permeability, self-sealing property, radio nuclides adsorption and retardation property, thermal conductivity, chemical buffering property, overpack supporting property, stress buffering property over a long period of time. Benotite is selected as the main content of buffer material that can satisfy above. GMZ deposit is selected as the candidate supplier for Chinese buffer material of High Level Radioactive waste repository. This paper presents geological features of GMZ deposit and basic property of GMZ Na bentonite. GMZ bentonite deposit is a super large scale deposits with high content of Montmorillonite (about $75\%$) and GMZ-l, which is Na-bentonite produced from GMZ deposit is selected as reference material for Chinese buffer material study.

• 한국초전도ㆍ저온공학회논문지
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• 제8권4호
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• pp.8-11
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• 2006

High temperature superconducting coated conductor has various buffer structures on Ni-W alloy. We comparatively studied the growth conditions of a multi buffer layer $(CeO_2/YSZ/CeO_2)$ and a single buffer layer$(CeO_2)$ on textured Ni-W alloy tapes. XRD data showed that the qualities of in-plane and out-of-plane textures of the two type buffer structures were good. Also, we investigated the properties of SmBCO superconducting layer that was deposited on the two type buffer structure. The SmBCO superconducting properties on the single and multi buffer structure showed different critical current values and surface morphologies. FWHM of In-plane and out-of-plane textures were $7.4^{\circ},\;5.0^{\circ}$ in the top CeO2 layer of the multi-buffer layers of $CeO_2/YSZ/CeO_2$, and $7.3^{\circ},\;5.1^{\circ}$ in the $CeO_2$ single buffer layer. $1{\mu}m-thick$ SmBCO superconducting layers were deposited on two type buffer layer. $I_c$ of SmBCO deposited on single and multi buffer were 90 A/cm, 150 A/cm and corresponding $J_c$ were $0.9MA/cm^2,\;1.5MA/cm^2$ at 77K in self-field, respectively.

• 전자공학회논문지SC
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• 제39권2호
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• pp.140-145
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• 2002

본 논문은 단락회로 전류를 없애기 위한 CMOS 버퍼회로에 대한 것이다. 최종 구동소자는 풀-업 PMOS와 풀-다운 NMOS로 구성하고 이를 구동하기 위해 두가지 경로를 입력신호로 선택되도록 하였다. 이러한 기법으로 최종 구동회로가 짧은 시간동안 tri-state가 되어 단락회로 전류를 차단하였다. 모의 실험결과 전원전압 3.3V에서 전력-지연 곱을 기존의 Tapered 버퍼[1]와 비교하여 약 42% 줄일 수 있었다

• 한국초전도ㆍ저온공학회논문지
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• 제6권4호
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• pp.1-4
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• 2004

Three group samples with difference thickness of $CeO_2$ capping layer deposited by PLD were studied. Among them, one group $CeO_2$ films were deposited on stainless steel tape coated with IBAD- YSZ and $CeO_2$ buffer layer ($CeO_2$/IBAD-YSZ/SS); other two groups of $CeO_2 YSZ Y_2O_3$multi-layer were deposited on NiW substrates for fabrication of YBCO coated conductor through RABiTS approach. The pulsed laser deposition (PLD) and DC magnetron sputtering were employed to deposit these buffer layers. On the top of buffer layer, YBCO film was deposited by PLD. The effect of thickness of $CeO_2$ film on the texture of $CeO_2$ film and critical current density ($J_c$) of YBCO film were analyzed. For the case $CeO_2$ on $CeO_2$/IBAD-YSZ/SS, there was a self-epitaxy effect with the increase of $CeO_2$ film. For $YSZ/Y_2O_3$ NiW which was deposited by PLD or DC magnetron sputtering, there is not self-epitaxy effect. However, the capping layer of $CeO_2$ film deposited by PLD improved the quality of buffer layer for $YSZ/Y_2O_3$ which was deposited by DC magnetron sputtering, therefore increased the $J_c$ of YBCO film.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.174-174
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• 2003

ZnO는 상온에서 3.36 eV의 wide band gap과 60 meV의 큰 엑시톤 결합 에너지를 가지며, GaN(28 meV)와 ZnSe(19 meV)와 같은 wide band gap 재료와 비교해서 가장 우수한 exciton emission을 가진다. 이러한 특성 때문에 UV 레이저 및 LED와 같은 광학소자로서 그 응용의 잠재성이 높다. 박막의 우수한 광학적 특성과 결정성을 개선하기 위해 다양한 공정조건(RF 파워, 공정압력, 산소분압, 온도)에서 마그네트론 스퍼터링을 이웅하여 Si 기판상에 ZnO 박막을 성장 하였다. 또한, 저온 self-buffer를 이용하여 박막의 광학적 특성과 결정성을 더욱 개선 할 수 있었다. RF 파워와 공정압력은 박막의 PL(phothluminescehce) 특성이나 결정성에는 큰 영향을 주지 않았고 산소분압은 PL intensity의 변화를 가져왔으며, 온도는 결정성에 큰 영향을 주었다. 산소 분압이 증가 할수록 비화학량론적(산소 공공, 침입형 아연) 결함으로 인한 visiable 영 역의 peak 의 강도가 감소하는 것을 관찰하였다. 온도가 증가할수록 박막의 결정성에 나쁜 영향을 주었는데 저온 self-buffer를 도입하므로써 ZnO 박막의 결정성과 PL특성을 함께 개선하였다.