• 한국압력기기공학회 논문집
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• 제14권2호
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• pp.32-40
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• 2018

Since 2000, the frequency of earthquakes beyond the 5.0 magnitude quake has been increasing in the Korean peninsula. For instance, the 5.0-magnitude earthquake in Baekryong-do in 2003 has occurred, and recent earthquake with Gyeongju(2016) and Pohang(2017) measured respectively magnitude of 5.2 and 5.8 on the Richter scale. As results, the public concern and anxiety about earthquakes are increasing, and therefore it is necessarily required for social infrastructure to reinforce seismic design and energy production facilities directly related to the national economy and security. This study represents the analysis of seismic performance evaluation methodology such as Seismic Margin Assessment (SMA), Seismic Probabilistic Risk Assessment (SPRA), High Confidence Low Probability Failure (HCLPF) in nuclear power plants in order to develop optimal seismic performance improvement. Current methodologies to evaluate nuclear power plants are also addressed. Through review of the nuclear structure evaluation past and current trend, it contributes to be the basis for the improvement of evaluation techniques on the next generation of nuclear power plants.

• Structural Engineering and Mechanics
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• 제82권3호
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• pp.271-282
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• 2022

The active learning surrogate model based on adaptive sampling strategy is increasingly popular in reliability analysis. However, most of the existing sampling strategies adopt the trial and error method to determine the size of the Monte Carlo (MC) candidate sample pool which satisfies the requirement of variation coefficient of failure probability. It will lead to a reduction in the calculation efficiency of reliability analysis. To avoid this defect, a new method for determining the optimal size of the MC candidate sample pool is proposed, and a new structural reliability analysis method combining polynomial chaos-based Kriging model (PC-Kriging) with adaptive sampling region is also proposed (PCK-ASR). Firstly, based on the lower limit of the confidence interval, a new method for estimating the optimal size of the MC candidate sample pool is proposed. Secondly, based on the upper limit of the confidence interval, an adaptive sampling region strategy similar to the radial centralized sampling method is developed. Then, the k-means++ clustering technique and the learning function LIF are used to complete the adaptive design of experiments (DoE). Finally, the effectiveness and accuracy of the PCK-ASR method are verified by three numerical examples and one practical engineering example.

• 한국엔터테인먼트산업학회논문지
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• 제14권5호
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• pp.115-130
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• 2020

본 연구의 목적은 에어로빅댄스 활성화를 위한 체중변화와 운동몰입에 관한 연구를 차이 분석하여 지속적으로 에어로빅댄스 활성화가 되도록 제시하는데 주된 목적이 있다. 이러한 연구 목적을 달성하기 위하여 2020년 4월에 경남에 소재한 일반 에어로빅댄스 회원들을 대상으로 선정하고 비확률표집방법(Non-Probability Sampling)의 하나인 편의표본추출법(Convenience Sampling Method)으로 표본 추출을 이용한 설문지로 시행하였다. 이와 같이 본 연구에서 얻어진 결과는 다음과 같다. 첫째, 인구통계학적 특성은 부분적으로 차이가 높게 나타났다. 연령은 40~49세, 신장은 160cm이상, 직업은 주부, 체중변화는 시작 후, 체중변화량은 -3kg 이상, 참여강도는 100분이상, 참여빈도는 4일, 참여기간은 5년이하가 가장 높게 나타났다. 둘째, 체중변화(신체자신감, 활동자신감, 댄스자신감, 심리안정효과, 댄스활동효과, 수행동작효과)와 운동몰입(행위몰입, 인지몰입)에 부분적으로 높은 차이가 나타났다. 셋째, 체중변화(신체자신감, 활동자신감, 댄스자신감, 심리안정효과, 댄스활동효과, 수행동작효과)와 운동몰입(행위몰입, 인지몰입)에 부분적으로 높은 영향이 미치는 것으로 나타났다.

• 한국전자파학회논문지
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• 제28권3호
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• pp.217-224
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• 2017

본 논문에서는 항공기 식별을 위해 서로 보완적인 특성을 갖는 HRRP 구분기와 JEM 구분기를 융합하여 식별하는 방법을 제안한다. 다양한 상황에서 단일 구분기보다 향상된 식별성능을 얻기 위하여 식별결과에 대한 구분기의 신뢰도를 가중치로 융합하는 방법을 제안한다. 신뢰도는 구분기의 식별성능으로부터 추정된 사후확률로 정의되며 식별결과에 대한 확신도 및 관측각도에 따라 변하는 특성을 가진다. 시뮬레이션 데이터를 사용한 식별실험을 통해 제안한 융합 방법이 단일 구분기를 효과적으로 융합하여 향상된 식별성능을 얻을 수 있음을 확인하였다.

• 응용통계연구
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• 제18권3호
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• pp.607-615
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• 2005

최근 여러 학자들에 의해 이항 비율의 구간 추정에 많이 사용되고 있는 Wald 신뢰구 간의 문제점이 재조명되고 있고, 이에 대한 대안으로 이항 비율의 새로운 신뢰구간들이 발표되고 있다. 본 논문에서는 가중 Polya posterior를 이용한 베이지안 구간추정을 구하였다. 이 구간추정은 이항분포의 공액분포인 베타 사전분포에서 구한 전통적인 베이지안 구간추정과 같으나 추정의 편의를 위하여 정규근사에 의한 신뢰구간을 구할 때, 표본크기가 크면 실제적으로 Argresti와 Coull (1998)의 신뢰구간과도 일치하였다. 또 새로운 신뢰구간은 표본크기가 작은 경우와 비율이 극히 작은 경우에도 매우 유용한 신뢰구간이 된다는 것을 살펴보았다.

• 응용통계연구
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• 제28권1호
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• pp.75-82
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• 2015

본 연구에서는 민감한 이항특성에 대한 신뢰구간 추정에 직접질문법과 간접질문법을 사용한다. 간접질문법으로 응답자들의 응답부담을 줄여주기 위해서 확률장치를 사용하는 Warner (1965)의 확률화응답기법(RRT)을 고려한다. 두 방법에 의한 신뢰구간을 비교하기 위해서 평가기준으로 평균포함확률(MCP), 평균제곱오차의 제곱근(RMSE), 그리고 평균기대폭(MEW)을 사용한다. 수치적 비교 결과 RRT의 MCP가 명목수준()을 크게 초과하여 보수적이고 MEW도 매우 크다. 따라서 이들을 보완해 주어야 실제적으로 간접질문법의 유용성을 높일 수 있다.

• 한국멀티미디어학회논문지
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• 제11권11호
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• pp.1471-1479
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• 2008

본 논문에서는 음성인식 분야에서 많이 사용되고 있는 가변어휘 단어 인식 시스템에서 미등록어에 대한 거절 성능을 향상시키는 방법을 제안한다. 거절 기능을 구현하는 방식은 핵심어 검출(keyword spotting)방식과 발화검증(utterance verification)으로 구분이 된다. 발화 검증 방식은 각 음소마다 이와 유사한 반음소모델(anti-phoneme model)을 생성한 후 정상적인 음소 모델과 반음소 모델의 유사도를 비교하여 결정하는 방식이다. 본 논문에서는 화자가 발성할 때마다 구해지는 화자확인 확률값을 신뢰도 문턱치를 결정할 때 적용하는 방법에 대하여 제안하였다. 제안한 방법을 사용하였을 때, 사무실 환경에서 CA(Correctly Accepted for keyword)가 94.23%, CR(Correctly Rejected for out-of-vocabulary)이 95.11%로 나타났고, 잡음 환경에서는 CA가 91.14%, CR이 92.74%로 나타나서 성능이 향상됨을 확인할 수 있었다.

• 한국임상수의학회지
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• 제27권4호
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• pp.421-426
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• 2010

In view of free from bluetongue (BT) in the domestic cattle population in Korea, the key of quarantine testing for BT virus (BTV) infection is detection of cattle previously exposed to the virus. The objective of this study was to estimate the probability of detecting a cattle infected with BTV using a stochastic modeling analysis of existing quarantine testing data. Three testing scenarios were considered in this study: serological testing of all animals in all imported lots (scenario 1), serological testing of a sample of cattle from all imported lots (scenario 2), and serological testing of 50% of imported lots (scenario 3). In scenario 2 and 3, it was assumed that cattle were sampled (sample size) within each lot to detect 5% of the cattle in each lot with a 95% confidence, taking into account diagnostic sensitivity of the ELISA (enzyme-linked immunosorbent assay). The model output was the total number of BTV-infected cattle and the prevalence of BTV infection in imported cattle from the US, Australia, Canada and Japan. Compared to the scenario 1, the probability of detecting a BTV-infected cattle was estimated to be 19% and 1.6% in scenario 2 and 3, respectively. Furthermore, the analyses showed a 95% confidence that BTV prevalence was less or equal to $9.7{\times}10^{-4}$ (median = $1.5{\times}10^{-5}$), indicating that, for the scenario 2 and 3 with serological testing for a sample of cattle, the risk of introducing an exotic strain of BTV into Korea through the importation of live cattle would not be acceptable.

• 수산해양기술연구
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• 제55권1호
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• pp.1-6
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• 2019

The annual production of silver croaker (Argyrosomus argentatus) in Korean towed fishing gears has been increased in recent five years. In 2017, the annual production of silver croaker in metric ton was increased 99.2% compared to 2013. However, the research for silver croaker has been focused on ecology in Korea. There has not been enough research in terms of fishing gears. Therefore, the research for retention probability for towed gears was conducted on covered codend method from June, 2016 to July, 2018. During the experiments, the total catch of silver croaker was 1,563. The geometry of the experimental trawl gear was controlled by trawl monitoring system; net height was 3.3 m, distance of trawldoors was 59.8 m and distance of wing net was 17.3 m. The selection curve for silver croaker was estimated by a logit model. The analysis was applied with the confidence interval to reduce uncertainty of the estimation. The $l_{50}$ was 13.87 cm and its selection range was 2.71 cm. P-value was estimated at 0.99. The mesh size for silver croaker in towed gears needs to be adjusted by considering its minimum maturity length, stakeholder's interests and fisheries regulations.

• Asian-Australasian Journal of Animal Sciences
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• 제23권4호
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• pp.425-429
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• 2010

To develop an efficient DNA typing system for Chinese Holstein cattle, 17 microsatellites, which were amplified in four fluorescent multiplex reactions and genotyped by two capillary electrophoresis injections, were evaluated for parentage verification and identity test. These markers were highly polymorphic with a mean of 8.35 alleles per locus and an average expected heterozygosity of 0.711 in 371 individuals. Parentage exclusion probability with only one sampled parent was approximately 0.999. Parentage exclusion probability when another parent' genotype was known was over 0.99999. Overall probability of identity, i.e. the probability that two animals share a common genotype by chance, was $1.52{\times}10^{-16}$. In a test case of parentage assignment, the 17 loci assigned 31 out of 33 cows to the pedigree sires with 95% confidence, while 2 cows were excluded from the paternity relationship with candidate sires. The results demonstrated the high efficacy of the 17 markers in parentage analysis and individual identification for Chinese Holstein cattle.