• International Journal of Oral Biology
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• 제44권4호
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• pp.152-159
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• 2019

The oral care probiotic strain Weissella cibaria CMU (oraCMU) inhibits volatile sulphur compounds associated with halitosis, presumably by inhibiting the growth of associated oral pathogens. In the present study, we investigated whether oraCMU inhibits the production of these compounds by suppressing the expression of mgl. This gene encodes L-methionine-α-deamino-γ-mercaptomethane-lyase (METase) and is involved in the production of methyl mercaptan (CH₃SH) by Porphyromonas gingivalis. Therefore, we specifically investigated the effects of oraCMU on the growth, CH₃SH production, METase activity, and mgl expression of P. gingivalis. The minimum inhibitory concentrations of cell-free supernatant and secreted proteins from oraCMU were 125 mg/mL and 800 ㎍/mL, respectively. At sub-minimum inhibitory concentration levels, these metabolites inhibited CH₃SH production, but they also reduced P. gingivalis viability. Only heat-killed oraCMU decreased CH₃SH production without affecting P. gingivalis viability. Heat-killed oraCMU also inhibited METase activity toward L-methionine and mgl mRNA expression (p < 0.05). In summary, we demonstrated the inhibition of volatile sulphur compounds via the antimicrobial action of oraCMU and, for the first time, the inhibition of such compounds by heat-killed oraCMU, which occurred at the molecular level.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권3호
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• pp.286-291
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• 2011

Purpose: The purpose of this study was to evaluate the use of OraQuick tests in previously reported articles. Methods: The literature was searched using Pubmed Medline with keywords, such as "OraQuick" or "rapid HIV test". Articles that included the specificity and sensitivity of this device were reviewed. Results: A total of 11 journal articles including 3 domestic articles were reviewed. The sensitivity of the OraQuick Test was reported to be 97.8 to 100% and its specificity was 98.8 to 100%. Conclusion: The results indicated that the simple OraQuick assay has proven to be accurate and it can be used to detect patients with HIV and to prevent the spread of HIV on test screens.

• International Journal of Oral Biology
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• 제43권4호
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• pp.193-200
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• 2018

The purpose of this study is to determine if natural extracts could be used as an additive in oral health food made with Weissella cibaria CMU (oraCMU). Natural extracts of green tea, mulberry leaf, licorice, and propolis, which are reported to have antimicrobial activities, were selected and used in this study. The minimum inhibitory concentrations (MIC) of extracts on periodontal pathogens such as Fusobacterium nucleatum and Porphyromonas gingivalis and their synergy effects with oraCMU by the fractional inhibitory concentrations methods were measured. From the results obtained, all the extracts showed no effect on the growth of oraCMU. Green tea extract showed the best antibacterial activity with MIC of 1.8 mg/ml against both F. nucleatum and P. gingivalis. In addition, green tea extract had a synergistic effect with oraCMU against F. nucleatum. Therefore, these results suggested that green tea extract is available as an additive in oral health food made with oraCMU.

• 한국환경보건학회지
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• 제44권3호
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• pp.217-226
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• 2018

Objectives: Despite the positive effects of Off-site risk assessment (ORA) system such as prevention of chemical accidents, some problems have been constantly raised. The purpose of this study is to analyze the problems that have occurred through the implementation of the ORA system for the past three years and to suggest reasonable directions for improvement in the future. Methods: In order to identify the problems with the methodology and procedure of ORA system, we analyzed statutes, administrative rules and documents related to the ORA system. A survey of ORA reviewers in National Institute of Chemical Safety was conducted to investigate the weight of determinants considered when judging the level of total risk in ORA. Results: In this study, we found out the uncertainty of the estimation of the number of people in the impact range in the procedure of the risk assessment of individual handling facilities, the lack of quantitative risk analysis methods for environmental receptors, and the ambiguity of the criteria for the total risk. In addition to suggesting solutions to the problems mentioned above, we also, suggested a decision tree for total risk in ORA. Conclusion: We anticipate that the solutions including the systematic decision tree for total risk suggested will contribute to the smooth operation of the ORA system.

• KIEE International Transactions on Power Engineering
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• 제4A권2호
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• pp.58-68
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• 2004

This paper presents an optimal routing algorithm (ORA) for maximizing voltage stability as well as for minimizing power loss in radial power systems. In the proposed ORA, a novel voltage stability index (VSI) for real-time assessment is newly introduced based on the conventional critical transmission path framework. In addition, the suggested algorithm can automatically detect the critical transmission paths resulting in voltage collapse when additional real or reactive loads are added. To implement an effective ORA, we have developed an improved branch exchange (IBE) method based on a loss calculation index and tie-branch power flow equations, which are suggested for real-time applications. The proposed algorithm has been tested with IEEE test systems as well as a large-scale power system in Korea to demonstrate its effectiveness and efficiency.

• 광학세계
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• 통권122호
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• pp.22-24
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• 2009

광학설계 프로그램 CODE V를 국내에 공급하고 있는 (주)모던하이테크(대표 김명중, www.okdomern.com)이 인하대학교 광기술교육센터 및 미Optical Research Associates(이하 ORA)와 함께 지난 6월 18일 서울 교육문화회관에서 '2009 CODE V User 컨퍼런스'를 개최하였다. CODE V 최신 버전 소개 및 특별강연이 진행된 이 행사에는 ORA사의 조지 베이스 사장이 참석하여 직접 비전을 소개하고 향후 국내 유저들을 위해 적극적인 서비스 지원을 약속했다.

• 환경영향평가
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• 제29권4호
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• pp.239-251
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• 2020

화학사고를 예방하기 위한 장외영향평가서에서는 유해화학물질 취급시설의 화학사고 위험도를 산정하고, 적절한 안전성 확보방안을 확보하도록 유도한다. 위험도를 산정하는 방법은 '사고영향범위 내 주민 수'와 '취급시설의 사고발생빈도'의 곱이다. 현재 장외영향평가서에서는 사고영향범위 내 피해 유형으로 영향범위 내 주민 수만 고려하고 있고, 환경수용체에 대한 정량적 고려가 이루어지지 않고 있다. 본 연구에서는 환경수용체를 고려한 위험도 산정 방식을 제안하였고, 가상의 시나리오 분석을 통해 주민에 대한 고려만 이루어진 위험도와 환경수용체를 고려한 위험도 산정방식을 비교 분석하였다. 이러한 연구를 통하여, 화학사고 예방을 위한 장외영향평가 제도에서 중·장기적으로 환경수용체를 고려한 위험도 분석의 필요성을 확인하고 방법론을 제안하였으며, 향후 정책 및 제도개선의 기초자료로 활용하기를 기대한다.

• Ocean and Polar Research
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• 제43권1호
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• pp.15-30
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• 2021

In this study, using 16 ORA-IP (Ocean Reanalysis Intercomparison Project) data, we investigated spatial and temporal changes of net surface heat flux in the East Asian seas and presented a new ensemble net surface heat flux index. The ensemble net surface heat flux index is produced considering the data distribution and the standard deviation of each ORA-IP. From the correlation analysis with air temperature averaged over the Korean Peninsula, ensemble net heat flux around the Korea Strait shows the highest correlation (0.731) with a 3 month time lag. For the correlation study regarding precipitation over the Korean Peninsula, it also shows significant correlation especially in winter and spring seasons. Similar results are also found in comparison with climate indices (AO, PDO, and NINO3.4), but ensemble net surface heat flux data in winter season reveals the strongest correlation patterns especially with winter temperature and spring precipitation.

• 한국도로학회논문집
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• 제9권4호
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• pp.215-226
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• 2007

차량방호 안전시설에 대한 성능의 검증은 충돌시험의 가속도와 각속도 데이터를 사용하여 산정한 탑승자 안전지수를 평가하여 이루어진다. 탑승자 안전지수로는 THIV(Theoretical Head Impact Velocity), PHD(Post-impact Head Deceleration), ASI(Acceleration Severity Index), OIV(Occupant Impact Velocity)와 ORA(Occupant Ridedown Acceleration)가 있다. 탑승자 안전지수 계산에 상이한 데이터 처리과정과 수치절차의 적용이 가능하기 때문에 동일한 시험 데이터에 대하여 다양한 탑승자 안전지수값이 결정될 수 있어서 혼란이 초래되고 있는 실정이다. 이러한 문제를 해결하기 위하여 다양한 상세절차와 데이터 처리과정이 탑승자 안전지수에 미치는 영향을 조사하였다. 지침에 제시된 계측시간간격을 사용하여 차량충돌시험이 수행된다면 보간법과 수치적분방법은 THIV와 OIV 값에 영향을 크게 미치지 않았다. 그리고 PHD에 대한 10msec 이동평균방법과 데이터 처리과정의 영점보정은 탑승자 안전지수에 상당한 영향을 미치기 때문에 이에 관한 구체적인 방법이 지침에 규정되어야 한다.

• 한국안전학회지
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• 제32권6호
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• pp.46-53
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• 2017

The risk is expressed as consequence of damage multiplied by likelihood of failure. The installation of a protective system reduces the risk by reducing the likelihood of failure at the facility. Also, the protective system has different effects on the likelihood of failure according to the proof test cycle. However, when assessing risks in the Off-site Risk Assessment (ORA) system, the variation in risk was not reflected according to the proof test cycle of protective system. This study was conducted to examine the need for proof test and the importance of cycle setting by applying periodic proof test of the protective system to ORA. The results showed that the likelihood of failure and the risk increased with longer proof test cycle. The risk of a two-yearly proof test was eight times greater than that of a three-month cycle. From the results, the protective system needs periodic proof test. Untested protective system for a long term cannot be reliable because it is more likely to be failed state when it is called upon to operate. In order to reduce the risk to an acceptable level, it is effective to differently set the proof test cycle according to the priority. This study suggested a more systematic and accurate risk analysis standard than ORA. This standard is expected to enable an acceptable level of risk management by systematically setting the priority and proof test cycle of the protective system. It is also expected to contribute to securing the safety of chemical facilities and at the same time, will lead to the development of the ORA system.