• 한국화재소방학회논문지
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• 제33권6호
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• pp.114-119
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• 2019

우리는 LED등기구의 Printed circuit board (PCB)에서 화재의 원인으로 특정할 수 있는 금속 마이그레이션(Metallic migration) 현상을 발견하고, 본 연구를 진행하였다. 금속 마이그레이션 현상 가속화 실험인 물방울 시험을 소량의 물과 저전압(3 V)로 진행하고 절연되어있는 양극에서 직접적으로 금속 마이그레이션의 성장과 회로의 단락을 확인하였다. 그리고 전자주사현미경(SEM)을 통해 형태를 관찰하고 에너지 분산형 분광기(EDS)를 이용하여 성분을 분석한 결과, 절연된 부분에서 전극을 이루고 있는 구리의 성분을 검출하였다.

• 수산해양기술연구
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• 제30권4호
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• pp.251-262
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• 1994

The speed of vertical migration and the volume backscattering strength of the scattering layers during the evening and morning transitions between day and night were measured in November 1990-1992 in thermally stratified waters of the East China Sea. Acoustical measurements were carried out using a scientific echo-sounder operating at t재 frequencies of 25 and 100kHz, and using an echo-integration system connected with a micro-computer. Biological sampling was accomplished by bottom trawling to identify fish species recorded on the echo sounder, and the species and length compositions were determined. The values of scattering strength were allocated to group of fishes according to the fish traces on the echo recording paper and the species composition of trawl catches. The vertical velocities of migration derived from the changes in the depths and the values of peak scattering strength of the dense layer vertically migrating toward the bottom or toward the surface. The trawl data suggest that snailfish and fishing frog were the most abundant fishes in all research stations. As sunrise approached, the fish formed a strong concentration just above the thermocline. The the highest values of scattering strength in the entire water column appeared in the depth strata above the thermocline just before the begining of downward migration. As soon as the fish began to migrate downwards across the thermocline, the values of the scattering strength in the depth strata above the thermocline rapidly decreased, while the values for the scattering layer moving slowly toward the bottom gradually increased. During the 1992 surveys, the speed of the vertical migration was estimated to be 0.38m/min in the upward migration and 0.32m/min in the downward migration, respectively. That is the rate of vertical migration was slightly higher at dusk than at dawn. Similar migration patterns were observed on different stations and under different weather conditions during the surveys in 1990.

• The Korean Journal of Physiology and Pharmacology
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• 제15권6호
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• pp.397-403
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• 2011

The proliferation, migration, cytokine release, and contraction of airway smooth muscle cells are key events in the airway remodeling process that occur in lung disease such as asthma, chronic obstruction pulmonary disease, and cancer. These events can be modulated by a number of factors, including cigarette smoke extract (CSE). CSE-induced alterations in the viability, migration, and contractile abilities of normal human airway cells remain unclear. This study investigated the effect of CSE on cell viability, migration, tumor necrosis factor (TNF)-${\alpha}$ secretion, and contraction in normal human bronchial smooth muscle cells (HBSMCs). Treatment of HBSMCs with 10% CSE induced cell death, and the death was accompanied by the generation of reactive oxygen species (ROS). CSE-induced cell death was reduced by N-acetyl-l-cysteine (NAC), an ROS scavenger. In addition, CSE reduced the migration ability of HBSMCs by 75%. The combination of NAC with CSE blocked the CSE-induced reduction of cell migration. However, CSE had no effect on TNF-${\alpha}$ secretion and NF-${\kappa}B$ activation. CSE induced an increase in intracellular $Ca^{2+}$ concentration in 64% of HBSMCs. CSE reduced the contractile ability of HBSMCs, and the ability was enhanced by NAC treatment. These results demonstrate that CSE treatment induces cell death and reduces migration and contraction by increasing ROS generation in normal HBSMCs. These results suggest that CSE may induce airway change through cell death and reduction in migration and contraction of normal HBSMCs.

• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2751-2756
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• 2015

Background: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can specifically induce apoptosis limited to various cancer cells, so this reagent is considered a promising medicine for cancer therapy. TRAIL also exerts effects on non-apoptotic signals, relevant to processes such as metastasis, autophagy and proliferation in cancer cells. However, the mechanisms of TRAIL-regulated non-apoptotic signals are unclear. The purpose of this study was to investigate MADD/CXCR7 effects in TRAIL-mediated breast cancer cell migration. Materials and Methods: The ability of MADD/CXCR7 to regulate MVP signaling in TRAIL-mediated breast cancer cells migration was evaluated by transwell migration assay, quantitative RT-PCR, Western blotting and knock down experiments. Results: In this study, we found that treatment with TRAIL resulted in induced expression levels of MADD and CXCR7 in breast cancer cells. Knock down of MADD followed by treatment with TRAIL resulted in increased cell migration compared to either treatment alone. Similarly, through overexpression and knockdown experiments, we demonstrated that CXCR7 also positively regulated TRAIL-inhibited migration. Surprisingly, knock down of MADD lead to inhibition of TRAIL-induced CXCR7 mRNA and protein expression and overexpression of CXCR7 lead to the reduction of MADD expression, indicating that MADD is an upstream regulatory factor of TRAIL-triggered CXCR7 production and a negative feedback mechanism between MADD and CXCR7. Furthermore, we showed that CXCR7 is involved in MADD-inhibited migration in breast cancer cells. Conclusions: Our work defined a novel signaling pathway implicated in the control of breast cancer migration.

• 정보보호학회논문지
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• 제27권2호
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• pp.315-327
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• 2017

가상머신 마이그레이션 과정에서 무단 접근, 데이터 변조 등의 보안 위협이 발생할 수 있다. 특히, 가상머신 마이그레이션은 사용자의 주요 데이터 및 중요 인프라 정보를 전송해야하기 때문에 해당 보안 위협이 발생할 경우 다른 클라우드 서비스에 비교적 위험성이 높다. 이러한 이유로 최근 가상머신 마이그레이션을 위한 동적인증의 필요성이 제기되고 있다. 이에 따라, 본 논문은 기존의 가상머신 마이그레이션을 위한 인증 기법의 취약점을 개선하기 위해 OTP 기반의 동적인증 프레임워크를 제안한다. 이는 가상머신 마이그레이션 요청 모듈 및 동작 모듈로 구성된다. 요청 모듈에서는 사용자가 마이그레이션 요청 시 OTP 기반의 사용자의 인증 과정 및 데이터 센터로의 마이그레이션 요청 과정을 포함한다. 동작 모듈에서는 SPEKE을 이용한 데이터 센터 간 안전한 키 교환 과정과 데이터 센터와 물리 서버 간 TOTP 기반의 상호인증 과정을 포함한다.

• Journal of Welding and Joining
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• 제25권3호
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• pp.57-63
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• 2007

Electrochemical migration characteristics of Pb-free solder alloys are quantitatively correlated with corrosion characteristics in harsh environment conditions. In-situ water drop test and corrosion resistance test for Sn-3.0Ag-0.5Cu solder alloys were carried out in NaBr and NaF solutions to obtain the electrochemical migration lifetime and pitting potential, respectively. Sn-3.0Ag-0.5Cu solder alloy shows similar ionization and electrochemical migration behavior with pure Sn because of Ag and Cu do not migrate due to the formation of resistant intermetallic compounds inside solder itself. Electrochemical migration lifetime in NaBr is longer than in NaF, which seems to be closely related to higher pitting potential in NaBr than NaF solution. Therefore, it was revealed that electrochemical migration lifetime of Sn-3.0Ag-0.5Cu solder alloys showed good correlation to the corrosion resistance, and also the initial ionization step at anode side is believed to be the rate-determining step during electrochemical migration of Pb-free solders in these environments.

• 디지털융복합연구
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• 제12권3호
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• pp.201-210
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• 2014

최근 들어 정보시스템을 구성하는 요소들이 복잡 해 짐에 따라 이것들의 이전에 따른 위험 부담도 증가하고 있다. 따라서 정보 시스템 이전 업무를 보다 체계적으로 수행할 필요성이 대두되고 있다. 또한 공공기관 정부이전으로 인하여 대규모의 정보시스템 이전이 진행되고 있으며 앞으로도 계속 추진될 것이다. 이에 따라서 본 논문에서는 정보시스템 이전 프로세스의 재정립과 이전의 효율성과 신속성을 확보하기 위하여 이전 솔루션을 사용할 것을 제안한다. 이것은 정보시스템 자산 이동 관리 추적 기능, 실시간 이동 위치 추적, 상황실을 통한 실시간모니터링 기능, 업무 속성에 따라 분리 이전 가능 시나리오의 제공 역할을 한다. 제안된 솔루션을 사용하면 정보시스템 이전의 시행착오를 감소시켜 이전시간을 최소화 하여 궁극적으로는 업무서비스의 공백을 없애는데 기여할 것이다.

• 대한본초학회지
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• 제23권3호
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• pp.155-162
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• 2008

Objectives : This study was evaluated to elucidate the inhibitory potential of Bodusan (BDS) and its components, Strychnos ignatii semen (SIS) and Glycyrrhizae Radix (GR), on human aortic smooth muscle cells (HASMC) migration and production of matrix metalloproteinase (MMP)-2 and MMP-9 by $TNF-{\alpha}$ treatment. Methods : Cytotoxic activity of BDS and its components on HASMC was using 5-(3-caroboxymeth- oxyphenyl)-2H-tetra-zolium inner salt (MTS) assay. Effect of BDS, SIS and GR on $TNF-{\alpha}-induced$ HASMC migration underside of matrigel filter was stained with hematoxylin-eosin. And total number of cells that migrated to the underside of the filter was counted. MMP-2 and MMP-9 activity was evaluated by gelatin zymography assay. Results : The matrigel migration assay showed that BDS effectively inhibited the $TNF-{\alpha}-induced$ migration of HASMC. Moreover, BDS significantly inhibited MMP-9 activity. Our present study demonstrates that BDS and its components inhibits $TNF-{\alpha}-induced$ HASMC migration and MMP-9 activity. The inhibitory effect of BDS extract is more potent than that of its component herb extracts. Conclusions : These results provide evidence that BDS has multiple effects in the inhibition of HASMC migration and may offer a therapeutic approach to block HASMC migration.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제11권4호
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• pp.293-304
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• 2005

본 논문에서는 글로버스(Globus) 기반의 MPICH-G2와 Cactus를 갖는 그리드 컴퓨팅 환경에서 작업 마이그레이션(Job Migration)에 대해 연구를 수행하였다. 그리드 컴퓨팅 환경에서 연산의 실행시간을 단축시킬 수 있는 연산자원이 풍부한 사이트를 찾아 작업을 마이그레이션 한다. 마이그레이션 사이트에서 체크 포인팅 파일에 기반 하여 연산의 수행이 중단된 지점부터 복구하여 연산을 재개한다. 마이그레이션 사이트를 선택하기 위해 사이트의 정적인 성능 지수와 CPU의 부하, 마이그레이션 작업을 전송하기 위한 네트워크의 부하를 고려한 작업 전송시간, 마이그레이션 사이트에서의 실행시간 예측 값을 사용하여 마이그레이션 이득이 큰 사이트로 작업을 마이그레이션 한다. 작업의 마이그레이션 시간과 실행시간 예측 값이 최소로 하는 사이트를 선택함으로서 보다 효율적인 그리드 컴퓨팅을 수행할 수 있도록 한다. 제안한 방법은 $K\ast{Grid}$ 환경에서 전체 연산 시간을 효과적으로 단축함을 입증하였다.

• Advances in concrete construction
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• 제1권3호
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• pp.239-252
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• 2013

Mortar microstructure is considered as a three-phase composite material, which is cement paste, fine aggregate and interfacial transition zone. Interfacial transition zone is the weakest link between the cement paste and fine aggregate, so it has a significant role to determine the properties of cementitious composites. In this study, specimens (w/c = 0.35, 0.45, 0.55) with various volume fractions of fine aggregate ($V_f$ = 0, 0.1, 0.2, 0.3 and 0.4) were cast and tested. To predict the equivalent migration coefficient ($M_e$) and migration coefficient of interfacial transition zone ($M_{itz}$), double-inclusion method and Mori-Tanaka theory were used to estimate. There are two stages to estimate and calculate the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$). The first stage, the data of experimental chloride ion migration coefficient ($M_s$) was used to calculate the equivalent migration coefficient of fine aggregate with interfacial transition zone ($M_e$) by Mori-Tanaka theory. The second stage, the thickness of interfacial transition zone (h) and migration coefficient of interfacial transition zone ($M_{itz}$) was calculated by Hori and Nemat-Nasser's double inclusion model. Between the theoretical and experimental data a comparison was conducted to investigate the behavior of interfacial transition zone in mortar and the effect of interfacial transition zone on the chloride migration coefficient, the results indicated that the numerical simulations is derived to the $M_{itz}/M_m$ ratio is 2.11~8.28. Additionally, thickness of interfacial transition zone is predicted from $10{\mu}m$, 60 to $80{\mu}m$, 70 to $100{\mu}m$ and 90 to $130{\mu}m$ for SM30, M35, M45 and M55, respectively.