• 한국정보과학회논문지:정보통신
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• 제41권4호
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• pp.167-176
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• 2014

본 논문은 이동 환경 위주의 미래 인터넷 환경을 위해 제안된 Mobile Oriented Future Internet (MOFI) 구조에 대하여 OpenFlow 기반 구현 이슈와 KOREN 실험망을 이용한 성능 분석을 논의한다. MOFI 구조는 호스트 식별자(host identifier)와 지역 위치자(local locator) 사용, 데이터 전달을 위한 Query 우선의 데이터 전달(Query-First Data Delivery), 식별자와 위치자간 분산형 매핑 시스템(Distributed Mapping System)을 특징으로 한다. 기존 MOFI 연구에서는 intra-domain 이동성 지원을 위해 6-to-4 터널링 기법 및 리눅스 플랫폼을 활용한 구현 방식을 제안하고 실험실 테스트베드에서 성능분석을 수행하였다. 한편, 본 논문에서는 inter-domain 이동성 지원을 위한 세부 절차를 논의하고 Click Modular Router와 OpenFlow 플랫폼을 활용한 MOFI 구현 방식을 제안한다. 나아가, 실제 KOREN 실험망을 활용한 성능 실험을 통해 MOFI 구조와 기존 이동성 제어 방식인 Proxy Mobile IP (PMIP) 기법을 비교한다. 실험 결과, 이동성 제어를 위한 시그널링 지연 시간 및 처리되는 메시지 수 측면에서 MOFI 구조가 기존 PMIP 이동성 제어 기법에 비하여 더 좋은 성능을 보이고 있음을 확인하였다.

• 한국ITS학회 논문지
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• 제22권6호
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• pp.77-91
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• 2023

최근 국내외에서 자율주행자동차의 상용화를 위한 연구개발이 활발히 진행중이며, 연속류 도로에서 레벨3 수준의 자율주행자동차들의 주행이 도입 및 증가될 것으로 예상된다. 이에 다양한 국내외 연구들에서 자율주행자동차의 시장점유율(MPR)에 따른 혼재 교통류 연구들이 진행되었으나, 각 연구들은 독립적으로 시행되어, 연구 결과에 따라 서로 다른 경향을 보인다. 이에 본 연구에서는 다수의 연구 결과들을 계량적으로 취합하여 통합된 결론을 내리는 메타분석 기법을 이용하여 연속류 도로에서 자율주행자동차의 혼재교통류의 영향을 분석하고자 하였다. 분석결과, 혼재율 75% 이상부터 추정된 효과크기가 통계적으로 유의미한 것으로 나타났으며, 자율주행자동차 혼재기에 연속류 도로 운영 및 관리를 위해서는 자율차 혼재기별 맞춤형 정책이 필요할 것으로 판단된다.

• 반도체디스플레이기술학회지
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• 제14권4호
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• pp.25-29
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• 2015

In this study, RF magnetron sputtering was used to investigate the relationship between oxygen vacancy and carrier concentration in a GZO film on an amorphous structure. RF power was fixed at 50W and Ar flow was changed on a glass plate to create a thin film at room temperature. The transmittance of Al-adopted amorphous GZO was measured at 85% or higher; therefore, the transmittance was shown to be outstanding in all films. The hall mobility was also shown to be higher at the film showing the high transmittance at a short-wavelength, whereas the optical energy gap was shown to be higher at the film with high oxygen vacancy. The oxygen vacancy at the amorphous oxide semi-conductor increased the optical energy gap while it was not directly involved in increasing the mobility. The oxygen vacancy increases the carrier concentration while lowering the quality of amorphous structure; such factor, therefore affected the mobility. The increase of amorphous property is a direct way to increase the mobility of amorphous oxide semi-conductor.

• 한국물환경학회지
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• 제23권5호
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• pp.577-580
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• 2007

The influence of flow rate has been investigated on the treatment efficiency of continuous cycling electrolytic process employing artificial and actual photographic wastewater which containing silver ion. For artificial wastewater, the treatment efficiency of process was found to rise ca. three times when the flow rate of wastewater was increased from 3 mL/min to 15 mL/min. The process efficiency was doubled under the same condition regarding actual wastewater. The effect of flow rate on the treatment efficiency was observed to be altered according to the metal ionic form and solution composition. The coefficient of mass transfer was estimated using model equation, which verified that the raised treatment efficiency at higher flow rate was due to the increased mobility of ionic species.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.786-794
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• 2022

Green ammonia is a promising renewable energy carrier. Green ammonia can be used in various energy conversion devices (e.g., engine, fuel cell, etc.). Ammonia has to be fed with hydrogen for start-up and failure protection of some energy conversion devices. Ammonia can be converted into hydrogen by decomposition and partial oxidation. Especially, partial oxidation has the advantages of fast start-up, thermally self-sustaining operation and compact size. In this paper, thermodynamics, start-up and operation characteristics of ammonia partial oxidation were investigated. O₂/NH₃ ratio, ammonia flow rate and catalyst volume were varied as operation parameters. In thermodynamic analysis, ammonia conversion was maximized in the O₂/NH₃ range from 0.10 to 0.15. Ammonia partial oxidation reactor was successfully started using 12 V glow plug. At 0.13 of O₂/HN₃ ratio and 10 LPM of ammonia flow rate, ammonia partial oxidation reactor showed 90% of ammonia conversion over commercial Ru catalyst. In addition, Increasing O₂/NH₃ ratio from 0.10 to 0.13 was more effective for high ammonia conversion than increasing catalyst volume at 0.10 of O₂/NH₃.

• Journal of Periodontal and Implant Science
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• 제21권2호
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• pp.191.1-191.1
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• 1991

• Journal of Periodontal and Implant Science
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• 제21권2호
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• pp.191.2-191.2
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• 1991

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1477-1479
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• 2005

In this work, the ITO thin films were prepared by FTS (Facing Targets Sputtering) system under different sputtering conditions which were varying $O_2$ gas flow, input current at room temperature. As a function of sputtering conditions, electrical and optical properties of prepared ITO thin films were measured. The electrical, optical characteristics and surface roughness of prepared ITO thin films were measured. In the results, as increasing $O_2$ gas 0.1[sccm] to 0.7[sccm], resistivity of ITO thin film was increased with a decreasing carrier concentration, $O_2$ gas over 0.3[sccm] the carrier mobility have a similarly value. Transmittance of prepared ITO thin films were improved at increasing $O_2$ gas 0.1[sccm] to 0.7[sccm]. And transmittance of all of the prepared ITO thin films was over 80%. We could obtain resistivity $6.19{\times}10^{-4}[{\omega}{\cdot}cm]$, carrier mobility $22.9[cm^2/V{\cdot}sec]$, carrier concentration $4.41{\times}10^{20}[cm^{-3}]$ and transmittance over 80% of ITO thin film prepared at working pressure 1mTorr, input current 0.4A without any substrate heating.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.797-800
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• 2006

The power flow analysis(PFA) can be effectively used to predict structural vibration in medium-to-high frequency ranges. In this paper, vibration experiment has been performed to observe the analytical characteristics of the power flow analysis of the vibration of a plate. In the experiment, the loss factor of the plate and the input mobility at a source point have been measured. The data for the loss factor has been used as the input data to predict the vibration of the plate with PFA. The frequency response functions have been measured over the surface of the plate. The comparison between the experimental results and the predicted results for the frequency responsefunctionshasbeenperformed.

• Bulletin of the Korean Chemical Society
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• 제21권9호
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• pp.875-881
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• 2000

We study the rheological properties of concentrated polymer solution and the melt under simple shear and elon-gational flow using Brownian dynamicssimulation. In order to describe the anisotropic molecular motion, we modifiedthe Giesekus' mobility tensor by incorporating the finitely extensible non-linear elastic (FENE) spring force into dumbbell model. To elucidate the nature of this model, our simulation results are compared with the data of FENE-P ("P"standsfor the Perterin) dumbbell model and experiments. While in steady state both original FENE and FENE-P models exhibit a similar viscosity response,the growthof viscosity becomes dissimilar as the anisotropy decreases and the flowrate increases. The steady state viscosity obtained from the simulation well describes the experiments including the shear-thinning behavior in shear flow and viscosity-thinning behavior in elongational flow. But the growth of viscosity oforiginal FENE dumbbell model cannot describe the experimental results in both flow fields.