• 시스템엔지니어링학술지
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• 제6권1호
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• pp.47-52
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• 2010

Human Factors Engineering (HFE) for Main Control Room (MCR) of Nuclear Power Plant (NPP) has been applied to optimize the design and operation of Man-Machine Interface (MMI) between operators and their equipment in consideration of physical, psychological and cognitive aspects. However, it has been observed that operators complain about environmental discomfort in the MCR since the operators in the MCR experience excessive stress due to the environmental factors such as inappropriate interior and lighting system. Since the HFE is an essential factor for the high fidelity performance of operators in the MCR, the adequate MCR environment design with HFE rules and guidelines is as much important to enhance the operability and reliability of the MCRs. Therefore, there has been a strong need to design a pleasant environment for the MCR to improve human performance of the operators.

• Annals of Laboratory Medicine
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• 제38권6호
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• pp.555-562
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• 2018

Background: The emerging mobile colistin resistance gene, mcr-1, is an ongoing worldwide concern and an evaluation of clinical isolates harboring this gene is required in Korea. We investigated mcr-1-possessing Enterobacteriaceae among Enterobacteriaceae strains isolated in Korea, and compared the genetic details of the plasmids with those in Escherichia coli isolates from livestock. Methods: Among 9,396 Enterobacteriaceae clinical isolates collected between 2010 and 2015, 1,347 (14.3%) strains were resistant to colistin and those were screened for mcr-1 by PCR. Colistin minimum inhibitory concentrations (MICs) were determined by microdilution, and conjugal transfer of the mcr-1-harboring plasmids was assessed by direct mating. Whole genomes of three mcr-1-positive Enterobacteriaceae clinical isolates and 11 livestock-origin mcr-1-positive E. coli isolates were sequenced. Results: Two E. coli and one Enterobacter aerogenes clinical isolates carried carried IncI2 plasmids harboring mcr-1, which conferred colistin resistance (E. coli MIC, 4 mg/L; E. aerogenes MIC, 32 mg/L). The strains possessed the complete conjugal machinery except for E. aerogenes harboring a truncated prepilin peptidase. The E. coli plasmid transferred more efficiently to E. coli than to Klebsiella pneumoniae or Enterobacter cloacae recipients. Among the three bacterial hosts, the colistin MIC was the highest for E. coli owing to the higher mcr-1-plasmid copy number and mcr-1 expression levels. Ten mcr-1-positive chicken-origin E. coli strains also possessed mcr-1-harboring IncI2 plasmids closely related to that in the clinical E. aerogenes isolate, and the remaining one porcine-origin E. coli possessed an mcr-1-harboring IncX4 plasmid. Conclusions: mcr-1-harboring IncI2 plasmids were identified in clinical Enterobacteriaceae isolates. These plasmids were closely associated with those in chicken-origin E. coli strains in Korea, supporting the concept of mcr-1 dissemination between humans and livestock.

• 정보관리학회지
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• 제27권3호
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• pp.265-281
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• 2010

본 연구에서 제안하는 기법은 최대 개념강도 인지기법(Maximal Concept-Strength Recognition Method: MCR)이다. 신규 데이터베이스가 입수되어 자동분류가 필요한 경우에, 기 구축된 여러 데이터 베이스 중에서 최적의 데이터베이스가 어떤 것인지 알 수 없는 상태에서 MCR 기법은 가장 유사한 데이터베이스를 선택할 수 있는 방법을 제공한다. 실험을 위해 서로 다른 4개의 학술 데이터베이스 환경을 구성하고 MCR 기법을 이용하여 최고의 성능값을 측정하였다. 실험 결과, MCR을 이용하여 최적의 데이터베이스를 정확히 선택할 수 있었으며 MCR을 이용한 자동분류 정확률도 최고치에 근접하는 결과를 보여주었다.

• Journal of Veterinary Science
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• 제22권5호
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• pp.68.1-68.15
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• 2021

Background: Colistin and carbapenem-resistant bacteria have emerged and become a serious public health concern, but their epidemiological data is still limited. Objectives: This study examined colistin and carbapenem resistance in Escherichia coli and Salmonella from pigs, pig carcasses, and pork in Thailand, Lao PDR, and Cambodia border provinces. Methods: The phenotypic and genotypic resistance to colistin and meropenem was determined in E. coli and Salmonella obtained from pigs, pig carcasses, and pork (n = 1,619). A conjugative experiment was performed in all isolates carrying the mcr gene (s) (n = 68). The plasmid replicon type was determined in the isolates carrying a conjugative plasmid with mcr by PCR-based replicon typing (n = 7). The genetic relatedness of mcr-positive Salmonella (n = 11) was investigated by multi-locus sequence typing. Results: Colistin resistance was more common in E. coli (8%) than Salmonella (1%). The highest resistance rate was found in E. coli (17.8%) and Salmonella (1.7%) from Cambodia. Colistin-resistance genes, mcr-1, mcr-3, and mcr-5, were identified, of which mcr-1 and mcr-3 were predominant in E. coli (5.8%) and Salmonella (1.7%), respectively. The mcr-5 gene was observed in E. coli from pork in Cambodia. Two colistin-susceptible pig isolates from Thailand carried both mcr-1 and mcr-3. Seven E. coli and Salmonella isolates contained mcr-1 or mcr-3 associated with the IncF and IncI plasmids. The mcr-positive Salmonella from Thailand and Cambodia were categorized into two clusters with 94%-97% similarity. None of these clusters was meropenem resistant. Conclusions: Colistin-resistant E. coli and Salmonella were distributed in pigs, pig carcasses, and pork in the border areas. Undivided-One Health collaboration is needed to address the issue.

• 한국통신학회논문지
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• 제25권8B호
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• pp.1357-1370
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• 2000

본 논문에서는 요구되는 서비스와 비트율에 따라서 칩률반송 주파수 처리 이득 그리고 전송 전력을 다르게 할당하는 비동기 multiple-chip-rate(MCR)-DS/CDMA 시스템의 성능을 분석하였다 향상된 정규 근사법의 간략화된 표현(SEIGA)은 성능 분석 중 비트 오율을 간단하게 하면서도 정확히 얻을 수 있는 방법으로 알려져 있는데 본 논문에서는 이방법을 MCR 시스템의 분석에 적용하여 그 결과를 얻도록 하였다 기존의 방법에서 사용하는 직접적으로 사용하기 때문에 계수사이의 직접전인 관계를 알 수 있다 제안된 과정을 이용하여 얻은 MCR-DS/CDMA 시스템의 성능 분석 결과를 모의 실험을 통하여 보여 주었다.

• Journal of Microbiology and Biotechnology
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• 제30권12호
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• pp.1862-1869
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• 2020

The spread of plasmid-mediated colistin resistance has posed a serious threat to public health owing to its effects on the emergence of pandrug-resistant bacteria. In this study, we investigated the prevalence and characteristics of mcr-1-positive Escherichia coli isolated from retail meat samples in Korea. In total, 1,205 E. coli strains were isolated from 3,234 retail meat samples in Korea. All E. coli strains were subjected to antimicrobial susceptibility testing and were examined for the presence of mcr-1 gene. All mcr-1-positive E. coli (n = 10, 0.8%) from retail meat were subjected to pulse-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS). The transferability of mcr-1 gene was determined by conjugation assays. The mcr-1-positive strains exhibited diverse clonal types. Our mcr-1 genes were located in plasmids belonged to the IncI2 (n = 1) and IncX4 (n = 8) types, which were reported to be prevalent in Asia and worldwide, respectively. Most mcr-1 genes from mcr-1-positive strains (9/10) were transferable to the recipient strain and the transfer frequencies ranged from 2.4 × 10-3 to 9.8 × 10-6. Our data suggest that the specific types of plasmid may play an important role in spreading plasmid-mediated colistin resistance in Korea. Furthermore, our findings suggest that the retail meat may be an important tool for disseminating plasmid-mediated colistin resistance.

• Nuclear Engineering and Technology
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• 제54권11호
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• pp.4195-4208
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• 2022

In this study, operator habitability was numerically evaluated in the event of a fire at the main control bench board (MCB) in a reference main control room (MCR). It was investigated if evacuation variables including hot gas layer temperature (HGLT), heat flux (HF), and optical density (OD) at 1.8 m from the MCR floor exceed the reference evacuation criteria provided in NUREG/CR-6850. For a fire model validation, the simulation results of the reference MCR were compared with existing experimental results on the same reference MCR. In the simulation, various input parameters were applied to the MCB panel fire scenario: MCR height, peak heat release rate (HRR) of a panel, number of panels where fire propagation occurs, fire propagation time, door open/close conditions, and mechanical ventilation operation. A specialized-average HRR (SAHRR) concept was newly devised to comprehensively investigate how the various input parameters affect the operator's habitability. Peak values of the evacuation variables normalized by evacuation criteria of NUREG/CR-6850 were well-correlated as the power function of the SAHRR for the various input parameters. In addition, the evacuation time map was newly utilized to investigate how the evacuation time for different SAHRR was affected by changing the various input parameters. In the previous studies, it was found that the OD is the most dominant variable to determine the MCR evacuation time. In this study, however, the evacuation time map showed that the HF is the most dominant factor at the condition of without-mechanical ventilation for the MCR with a partially-open false ceiling, but the OD is the most dominant factor for all the other conditions. Therefore, the method using the SAHRR and the evacuation time map was very useful to effectively and comprehensively evaluate the operator habitability for the various input parameters in the event of MCB fires for the reference MCR.

• 대한전자공학회논문지TC
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• 제44권10호
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• pp.110-118
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• 2007

멀티 홈 무선 네트워크에서 멀티 채널의 사용은 무선노드의 채널 간섭 및 채널 경쟁을 줄임으로써 네트워크 성능을 향상시킨다. 최근 이를 위한 다양한 기법들이 제안되고 있다 특히 하이브리드 인터페이스 할당 방식을 사용하는 MCR(Multi channel routing protocol)은 간단한 채널 할당 방법을 통해 채널 간섭을 줄여주는 대표적인 라우팅 기술이다. 본 논문에서는 MCR의 링크 계층에서 사용하고 있는 채널 스위칭 알고리즘의 문제점을 지적하고 이를 개선할 수 있는 방안으로 트래픽 부하를 고려한 채널 스위칭 알고리즘인 LCS(Load-aware channel switching) 방안을 제안한다. LCS에서는 이웃 노드의 큐 상태 정보를 수집하여 네트워크 트래픽 상황을 파악하고 이를 바탕으로 최선의 채널을 선택한다. 또한 본 논문에서는 시뮬레이션과 테스트 베드 실험을 통해 LCS의 성능을 시험한다. 시험 결과 LCS를 적용한 MCR이 기존의 채널 스위칭 알고리즘 보다 향상된 성능을 보였다.

• 보험의학회지
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• 제27권1호
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• pp.33-36
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• 2008

BACKGROUND : The medical claims review(MCR) is unique methodology of medical consultation in terms of insurance claim administration in Korean insurance market. The most important practical matter in the MCR is formatted question. In Korea, medical specialty is composed of 26 legally defined hospital departments. It is worth of studying to investigate type of MCR by hospital departments. METHODS : Fifty Cases of the MCR were selected randomly by statistical program SPSS among 1,032 cases which were performed between April 1, 2006 and March 31 2007. All of selected cases were evaluated one insurance doctor and made a score points from 0 to 10 in terms of hospital department. RESULTS : Multidimensional scaling was performed. The MCR types - diagnosis, malignancy and cause of death are located in the same 2-dimensional configuration area. It can be called as verification of benefit. Others are advice. - such as causality, interpretation, translation, independent medical examination, and so on. DISCUSSION : We can conclude the classification of MCR typology are two main subjects, verification and advice. Theses results are same as previous article which was based on experience.

• 한국산업정보학회논문지
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• 제10권1호
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• pp.49-57
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• 2005

ATM 포럼은 ATM 네트워크에서 TCP 트래픽에게 MCR을 보장하고, 여분의 대역폭을 공정하게 공유할 수 있도록 GFR 서비스를 정의하였다 GFR 스위치 구현 방법은 F-GCRA 알고리즘과 프레임 전달 메커니즘으로 이루어진다. F-GCRA 알고리즘은 MCR 보장에 적합한 프레임을 분류한다. 프레임 전달 메커니즘은 F-GCRA의 분류 정보에 따라 프레임 단위로 셀을 저장하고, 스케줄링 기법에 따라 출력 단자로 저장된 셀을 전달한다 전역 임계값을 갖는 공유 버퍼로 이루어진 단순 GFR 메커니즘은 단순한 구조로 인해 구현이 용이 하지만, MCR를 보장하는데 충분치 않다고 알려져 있다 본 논문은 단순 GFR 메커니즘을 갖는 ATM 스위치에서 TCP 트래픽을 위한 GFR 서비스 성능을 평가한다.