• 한국항공운항학회지
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• 제25권4호
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• pp.195-203
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• 2017

Around 70% of domestic aircraft accidents in helicopter aircraft. The causal factors of the helicopter accidents are identified as human factors. People have focused mostly on unsafe acts to prevent the accident. The accidents should be analysed on human factors to reduce accident. The unsafe acts can be managed effectively if the latent failures were identified through the HFACS. This paper is to introduce about the latent failure classified by the HFACS and provide the analysis regarding the latent failure of the helicopters by the aviation safety advisors through the interviews.

• 한국항공운항학회지
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• 제22권4호
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• pp.56-64
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• 2014

There were a total of 65 accidents of helicopers between 1990 and 2013. The overall accidents rate has remained around 8 accidents per 100,000 flight hours, and the fatal rate has stayed at about 8 accidents per 100,000 flight hours. In this study, we conduct a series of statistical analyses to investigate the significance of latent failure of groups that operate the helicopter. Analysis of variance demonstrated significant differences in the latent condition score for the 3 groups, with the lower accidents rate groups reporting better scores of latent condition. Results indicated that there are the significant differences of latent condition in accidents between groups of high accidents rate and groups of low accidents rate.

• 품질경영학회지
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• 제23권1호
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• pp.50-63
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• 1995

We study under what condition the probability of the failure state of each component is realized by the latent stress model which considers the cause of the failure as well as the state of the given system. As a result, when the number of the components is less than or equal to 3, the $MTP_2$ property is a necessary and sufficient condition for the realization of the probability of system state by the latent stress model. Moreover, if the probability of the system state involving 2 or 3 components satisfies the $MTP_2$ property, one could guess that each component is under the same stress.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 B
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• pp.871-873
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• 1999

According to the reports about the failure mode analysis of modules and systems, It is said that there are many early failure of system. To remove latent defects which causes early failures like that, It is necessary that screening test is performed. ESS is often used fur screening electronic equipments, and is proposed by the most powerful tool for removing latent defects of electronic equipments. [1][2] In this report, the procedure of the environmental stress screening which uses the temperature cycling stress is proposed. It is considered about environmental conditions of distributed control system(DCS) to be tested, design specifications of the system, recommended conditions of relative IEC-STD and applied conditions of similar company. ESS test was applied at the DCS to be installed in power plant. As the results of analyzing discovered problems. It was found that almost latent defects of electronic control systems was discovered early.

• International Journal of Reliability and Applications
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• 제6권2호
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• pp.101-115
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• 2005

This article provides a new class of multivariate linear failure rate distributions where every component is a mixture of linear failure rate distribution. The new class includes several multivariate and bivariate models including Marslall and Olkin type. The approach in this paper is based on the introducing a linear failure rate distributed latent random variable. The distribution of minimum in a competing risk model is discussed.

• 사회복지연구
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• 제43권1호
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• pp.5-29
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• 2012

비행경험이 많을수록 자신을 비행청소년으로 인식할 것으로 예상되지만, 청소년들의 일탈적 자아개념의 변량 중 비행경험으로 인해 설명되는 변량은 비교적 작은 수준에 불과하다. 본 연구의 목적은 비행경험을 통제한 후에도, 또는 비행경험이 없음에도 불구하고 자신을 문제아 또는 비행청소년으로 인식하게 만드는 요인이 무엇인지 규명하는데 있었다. 특히 비행경험 이외에 청소년기 중요한 발달과업(성취와 관계)에서의 실패가 일탈적 자아개념과 어떠한 관계에 있는지, 더 나아가 이러한 관계에 내재한 성별 차이를 규명하는데 목적을 두었다. 한국청소년패널조사의 중2에서 고3까지 5년 종단자료에 대해 잠재 상태-특성 자기회귀 모델(latent state-trait autoregressive model)을 적용하여 일탈적 자아개념에 내포된 변동적 상태요인을 통제한 후 청소년기에 걸쳐 안정적인 특성적 일탈자아를 설명하는 예측요인이 무엇인지 알아보았다. 연구결과, 비행경험 이외에 학업성취, 친구관계 및 부모관계가 청소년기 일탈적 자아개념의 특성적 요인을 유의미하게 설명하는 것으로 나타났다. 비행경험의 효과에 유의미한 성별 차이가 나타난 바, 남자청소년에 비해 여자청소년이 비행경험으로 인해 자신을 문제아로 인식하였다. 비행경험을 통제한 후에도 학업성취 및 관계에서의 실패와 유능감 부족은 청소년기 일탈적 자아개념의 형성에 영향을 미치는 것으로 나타났다. 특히 친구관계에서의 실패는 남자보다 여자에게 더 중요한 예측요인인 반면, 학업성취에서의 실패는 남녀에게 모두 유의미한 일탈적 자아개념의 예측요인으로 나타나 한국사회의 성취지향적 가치체계와 문화가 청소년기 일탈적 자아개념에 반영되고 있음이 검증되었다

• Diabetes and Metabolism Journal
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• 제42권6호
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• pp.451-464
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• 2018

Latent autoimmune diabetes in adults (LADA) is a heterogeneous disease characterized by a less intensive autoimmune process and a broad clinical phenotype compared to classical type 1 diabetes mellitus (T1DM), sharing features with both type 2 diabetes mellitus (T2DM) and T1DM. Since patients affected by LADA are initially insulin independent and recognizable only by testing for islet-cell autoantibodies, it could be difficult to identify LADA in clinical setting and a high misdiagnosis rate still remains among patients with T2DM. Ideally, islet-cell autoantibodies screening should be performed in subjects with newly diagnosed T2DM, ensuring a closer monitoring of those resulted positive and avoiding treatment of hyperglycaemia which might increase the rate of ${\beta}-cells$ loss. Thus, since the autoimmune process in LADA seems to be slower than in classical T1DM, there is a wider window for new therapeutic interventions that may slow down ${\beta}-cell$ failure. This review summarizes the current understanding of LADA, by evaluating data from most recent studies, the actual gaps in diagnosis and management. Finally, we critically highlight and discuss novel findings and future perspectives on the therapeutic approach in LADA.

• 한국정보처리학회논문지
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• 제6권8호
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• pp.2060-2071
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• 1999

소프트웨어 시스템이 복잡해지면 고장의 원인이 하나의 강도함수에 의해서만 일어나지 않고 여러 원인이 중첩되어 발생할 수 있다. 이러한 복잡한 시스템에 의한 우도함수의 계산상의 어려움 때문에 반복표본을 이용하는 깁스 샘플링 기법이 고려되었다. 관찰된 고장시점은 중첩모형으로 표현이 가능한 잠재(latent)변수들을 이용하여 깁스 알고리즘을 적용하였다. 단순모형과 중첩모형의 비교를 위해 사후베이즈 요인과 상대오차의 합을 이용하여 모형선택을 시도하였다. 수치적인 예에서 GOS 속성을 가진 Goel-Okumoto 모형과 Weibull 모형을 선택하고 NHPP의 자료는 Lewis와 Shedler[25]에 의해 제시된 Thining 알고리즘을 이용하여 발생된 자료를 이용하고 사전분포는 상대적으로 확산분포(diffuse priors)를 이용한 모수추정과 사후베이즈요인과 상대오차를 이용한 모형선택을 한 결과 단순모형들 보다 중첩모형이 좋은 형으로 간주할 수 있음을 보여 주었다.

• 대한안전경영과학회지
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• 제15권4호
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• pp.81-88
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• 2013

In Korean society, the theme of human errors in railway has been emerging as a critical issue. As far as human error studies are concerned, main trend has been inclined to be led by industrial engineering and systems science. Apart from those trends, this study empirically highlighted the relationship between depression, which has been a frequent research subject in the medical science and psychology, and accidents, with setting depression as an exogenous variable and cognitive failure and mistake as endogenous variables, respectively. Results of hypotheses test for the 204 respondents showed that driver's depression has a significant effect on accidents mediated by cognitive failure and mistake. This findings suggest the need for exploring the diverse latent factors causing human errors and for understanding the complex cognitive process as well as for establishing integrative countermeasures to mitigate human errors.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 춘계학술대회 논문집
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• pp.358-362
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• 1995

Precision electronic equipments are composed of sophisticated microcircuits that are extremely vulnerable to lightning-caused voltage spike. This transient voltage spike may cause upset, latent failure or interference on electronic equipments. In order to develop efficient lightning protection measures on AC power lines for a road traffic controller, experimental surge immunity tests were conducted according to IEC standard 801-5. The combination of gas tube arrester and metal-oxide varistor was installed at the input of AC power lines and the silicon avalanche suppressor installed at the output of DC power supply as lightning protection measures.