• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1179-1186
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• 2009

The high-speed train(KTX) was operated in domestic since 2004 and 4years have been passed since then. At the beginning most of the KTX component maintenance period was followed by the France SNCF. It was settled by the TBO(Time Between Overhauls). But the environment and operation condition are different form each other, so the TBO maintenance period can be different in some component. Therefore new TBO is necessary based on our own circumstances. This paper introduces failure analysis case on some components to set TBO in domestic. KTX-RCM(Reliability Centered Maintenance System), MICS(Maintenance Information Computer System) and KOVIS(KORAIL ERP System) Data was investigated.

• 한국항공우주학회지
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• 제43권4호
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• pp.349-358
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• 2015

본 논문은 미래 항공교통관리(Air Traffic Management, ATM)의 핵심개념으로 받아들여지고 있는 궤적기반운용(Trajectory-based Operations, TBO)에 대한 기술동향을 담고 있다. ICAO(International Civil Aviation Organization)가 발표한 ASBU(Aviation System Block Upgrade)에 기술된 TBO 운용개념을 살펴보고, 미국과 유럽에서 각각 진행 되어온 궤적기반운용에 대한 운용개념 수립과 관련 연구개발 사례들을 통해 근 미래에 실현 가능한 운용개념 및 절차를 구체화하였다. 운용개념 정리를 통해 파악된 요소기술들(technical enablers)을 간단히 소개하며, 관련된 연구개발 진행 현황을 정리하였다.

• Clinical and Experimental Vaccine Research
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• 제12권4호
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• pp.304-312
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• 2023

Purpose: Due to the many problems with commercially available vaccines, the production of effective vaccines against brucellosis is a necessity. The aim of this study was to evaluate the immune responses caused by the chimeric protein consisting of trigger factor, Bp26, and Omp31 (TBO) along with aluminum hydroxide (AH/TBO) and selenium (Se/TBO) nanoparticles (NPs) as adjuvants in mouse model. Materials and Methods: Recombinant antigen expression was induced in Escherichia coli BL21 (DE3) bacteria using IPTG (isopropyl-d-1-thiogalactopyranoside). Purification and characterization of recombinant protein was conducted through NiFe₃O₄ NPs, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blot. NP characteristics, including morphology and particle size, were measured in vitro. The recombinant TBO was loaded on to AH and Se NPs and were administered subcutaneously. After mice immunization, measurement of antibody titter and protection assay was performed. Results: The average sizes of AH and Se NPs were about 60 nm and 150 nm, respectively. The enzyme-linked immunosorbent assay results showed that the serum of mice immunized by subcutaneous injection with both nanovaccines produced significant immunoglobulin G (IgG) responses against the chimeric antigen. The results of TBO-specific IgG isotype (IgG2a/IgG1) analysis showed that both AH and Se NPs induced a type to T-helper immune response. In addition, the results of the challenge with the pathogenic strain of Brucella melitensis 16M showed that vaccinated mice with AH/TBO NPs indicated a higher reduction of bacterial culture than immunized mice with Se/TBO NPs and TBO alone. Conclusion: The results showed that AH NPs carrying chimeric antigen can be a promising vaccine candidate against brucellosis by producing protective immunity.

• 한국항공운항학회지
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• 제22권3호
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• pp.82-86
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• 2014

Modern Air Traffic Management has been shifted from the conventional vector- based clearances to trajectory based operations (TBO) concept which utilizes four-dimensional trajectory based on the internationally interoperable information using Globally Unique Flight Identifier (GUFI). This study reviews the development for TBO-related standards and Flight Information Exchange Model (FIXM), which has been discussed by the ICAO Air Traffic Management Requirements and Performance Panel (ATMRPP). In addition, plans for the next step with TBO and the Republic of Korea's participation on the Mini-Global Demonstration were also introduced.

• International Journal of Aeronautical and Space Sciences
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• 제17권4호
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• pp.604-613
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• 2016

In this paper, Human-in-the-Loop (HiTL) simulations of Remotely Piloted Aircraft System (RPAS) operations in two different Air Traffic Management (ATM) concepts, conventional radar vectoring and Trajectory Based Operations (TBO), were performed to assess the impacts of RPAS integration in the future ATM environment. TBO concept maximizes the throughput by planning and sharing 4-D trajectories between pilots and controllers, and it is considered one of the key concepts to enable RPASs to operate with manned aircraft in congested airspaces. RPASs are characterized by having communication delay or temporary loss of communication. TBO capability was added to the integrated air traffic simulation system for this study, which was developed in the Inha University. HiTL simulations were performed by a trainee air traffic controller with three scenarios, and the data were analyzed using safety, efficiency, and controller workload metrics. The results suggest that TBO were effective in reducing delays and controller workload while maintaining the level of safety.

• Journal of Oral Medicine and Pain
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• 제35권1호
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• pp.31-39
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• 2010

치주염이나 구취발생과 관련된 구강미생물에 대한 저출력레이저의 살균효과를 관찰하기 위하여, Porphyromonas gingivalis 2561 (P. gingivalis 2561), Prevotella intermedia (Pr. intermedia)에 광감수성증가물질을 처리함으로써 실험균주의 광민감성을 증가시킨 후 저출력레이저 650nm의 파장을 연속적으로 1분, 2분, 3분, 5분간, 각각 1cm, 2cm, 3cm 거리에서 조사하여 다음과 같은 결과를 얻었다. 1. P. gingivalis 2561의 경우 Toluidine blue O(TBO) 처리 후 650nm의 파장으로 3cm의 거리에서 1분간 조사한 실험군은 TBO만 처리한 실험대조군에 비해 99.99% 이상의 항균효과를 나타내었다. 2. Pr. intermedia의 경우 TBO 처리 후 650 nm의 파장으로 3 cm의 거리에서 1분간 조사한 실험군은 TBO만 처리한 실험대조군에 비해 99.8% 이상의 항균효과를 나타내었다. 3. P. gingivalis 2561의 경우 TBO 처리 후 650 nm의 파장을 연속으로 각각 1분, 2분, 3분간 조사한 실험군의 경우 시간이 길어질수록 살균효과가 점차 증가되었다. 4. P. gingivalis 2561의 경우 조사거리가 1 cm, 2 cm, 3 cm으로 증가할수록 살균효과가 약간 감소되었다. 5. Pr. intermedia의 경우 조사거리가 1 cm, 2 cm, 3 cm으로 증가할수록 살균효과가 약간 감소되었다. 위와 같은 결과를 바탕으로 저출력레이저의 살균효과는 조사시간이 길어질수록, 조사거리가 짧을수록 살균효과가 증가되었는데, 살균효과가 가장 적게 나타난 3 cm의 거리에서 1분간 조사한 실험군에서도 TBO만 처리한 경우보다 99.8% 이상의 살균효과를 나타내었으므로 저출력레이저의 구강미생물에 대한 살균효과는 명백하다고 생각된다. 따라서 photosensitizer의 부작용이 없는 한계 내에서 사용한다면 저출력레이저가 치주염, 임플란트주위염 등에 대한 보조적 치료와 구취조절 등에 매우 유용하게 사용되리라고 생각된다.

• 한국안전학회지
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• 제36권2호
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• pp.1-9
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• 2021

The 8200-unit electric locomotive, which is a high-efficiency multipurpose electric locomotive, is a German model, namely BR152 series ES64F, and it is manufactured to suit the operating conditions in Korea. Since 2003, 83 locomotives have been introduced in Korea, and they have been operating in the general railway sector for both passenger and freight transport. Although more than 15 years have passed since their first introduction, owing to the characteristics of vehicles introduced overseas, responding promptly to failures has been difficult owing to problems related to factors such as transfer of technology and procurement of parts for maintenance. Furthermore, there have been difficulties in operating the locomotives on the basis of the manufacturer-recommended time-between-overhaul (TBO) cycle. Therefore, a new TBO should be determined. To support the development of a reliability-based maintenance system, this study conducted a reliability and TBO analysis by using failure data obtained from KOVIS, and future management measures are presented.

• 한국산학기술학회논문지
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• 제16권12호
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• pp.8700-8706
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• 2015

고속철도차량 동력대차의 1차 구동장치는 모터 감속기와 견인전동기로 구성한다. 모터 감속기와 견인전동기는 기계적으로 일체형 결합 구조이지만, 상이한 기술 요구사항으로 인하여 이들의 완전 분해정비 주기는 서로 다르다(모터 감속기의 완전 분해정비 주기: $1.8{\times}10^6km$, 견인전동기의 완전 분해정비 주기: $2.5{\times}10^6km$). 따라서 불필요한 정비 횟수를 감소하기 위하여 신뢰성 중심 유지보수 관점에서 최적의 완전 분해정비 주기의 산정이 중요하다. 본 연구에서는 실제 유지보수 정비이력으로부터 두 구성품들에 대한 고장 결함나무 분석을 수행하고 각 하부부품들의 치명도를 고려한 고장률을 각각 평가하였다. 두 구성품에 대한 최적의 동일한 완전분해 정비주기는 기존의 총 예방정비 비용을 감소하기 위하여 유전자 알고리즘으로 부터 얻었다. 이 알고리즘에서 각 개체를 구성하는 유전자는 최소 예방 정비주기이며, 이의 조합으로 구성된 세대별 개체의 적합도함수는 총 정비비용의 역수로 공식화하여 얻는다. 최소공배수에 의한 방법은 기존 대비 4%만 감소하지만, 유전자 알고리즘에 의한 최적의 동일 완전분해 정비주기는 225만km로서 기존 방법의 총비용과 비교하여 약 14% 감소하였다.

• Applied Biological Chemistry
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• 제38권5호
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• pp.447-451
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• 1995

자연계에 풍부한 천연고분자물질인 키틴을 탈아세틸화하여 얻어지는 키토산을 색소의 흡착제로 이용하고자, 색소 Toluidine Blue O(TBO)에 대한 키토산의 흡착 특성을 연구하였다. 키토산과 TBO의 흡착반응에는 키토산 입경, 키토산의 양, TBO의 초기 농도, 반응액의 pH, 반응시간 등이 중요한 인자로 작용하는 것으로 밝혀졌다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1191-1197
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• 2009

KTX decelerator is a device to fulfil a role of transmission of turning force to reduction device of an axle by serrate device. Currently, KTX decelerator's TBO(Time Between Overhaul) has 3 years cycle. As for the dissembly maintenance of a device, its maintenance is conducted every 1.4M kms. In this study, since opening of KTX, we analyzed reliability, maintainability, availability of KTX decelerator by researching historical records of maintenance of the decelerator, and based on above data, investigated whether its TBO cycle and maintenance works properly or not And we considered maintenance policies of KTX decelerator to improve efficiency in maintenance in the future.