• The Korean Journal of Applied Statistics
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• v.23 no.5
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• pp.943-953
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• 2010

From a mixture distribution of the score random variable for credit evaluation, there are many methods of estimating optimal thresholds. Most the research news is based on the assumption of normal distributions. In this paper, we extend non-normal distributions such as Weibull, Logistic and Gamma distributions to estimate an optimal threshold by using a hypotheses test method and other methods maximizing the total accuracy and the true rate. The type I and II errors are obtained and compared with their sums. Finally we discuss their e ciency and derive conclusions for non-normal distributions.

• Journal of the Korean Solar Energy Society
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• v.29 no.2
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• pp.22-30
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• 2009

In order to clarify predictive accuracy for the wind resource predicted by running WindPRO(Ver. 2.5) which is software for wind farm design developed by EMD from Denmark, an investigation was carried out at the northeast region of Jeju island. The Hangwon, Susan and Hoichun sites of Jeju island were selected for this study. The measurement period of wind at the sites was for one year. As a result, when the sites had different energy roses, though the two Wind Statistics made by STATGEN module were used for the prediction, it was difficult to exactly predict the energy rose at a given site. On the other hand, when the two Wind Statistics were used to predict the average wind speed, the wind power density and the annual energy production, the relative error was under ${\pm}20%$ which improved more than that when using only one Wind Statistics.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.966-971
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• 2003

[ $\lceil\;Cost Effectiveness Analysis\;\rfloor$ ] has been widely used to evaluate effectiveness of R&D resources. But, almost of cost effectiveness evaluation systems have some problems, especially estimating method of effect on R&D project is very rough and imprecise. To solve this problem, we have designed new single effect evaluation system, which are able to apply the distribution of order statistics and to transform relative measure into absolute measure for getting single effect.

• Journal of the Korean Data and Information Science Society
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• v.15 no.1
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• pp.183-191
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• 2004

This paper shows that there are some extra-factors on the evaluation of lecture by students. The extra-factors are sex, day and nighttime, academic year, size of lecture, and grades. And this paper analysis the proportion of the student which put the same mark on all items(same marked proportion).

• Communications of the Korean Mathematical Society
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• v.38 no.1
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• pp.257-266
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• 2023

Let G_k,n(ℍ) for 2 ≤ k < n denote the Grassmann manifold of k-dimensional vector subspaces of ℍⁿ. In this paper, we determine the evaluation subgroups of the Plüker embedding $G{_{2,n}}({\mathbb{H}}){\hookrightarrow}{\mathbb{H}}P^{N-1}$, where $N\;=\;({n \atop 2}\)$.

• Proceedings of the Korean Reliability Society Conference
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• 2001.06a
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• pp.463-469
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• 2001

An algorithm is presenter for generating the most probable states in decreasing order of probability of each unit. The proposed new algorithm in this note is compared with the existing methods regarding memory requirement and execution time. Our method is simpler and, judging from the computing experiment, it requires less memory size than the previously known methods and takes comparable execution time to previous methods for an acceptable level of criterion.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.134-134
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• 2001

• Proceedings of the Korean Statistical Society Conference
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• 2002.11a
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• pp.119-124
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• 2002

We consider a multi-state flow network consisted of undirected links and focus on how to find efficiently the union of minimal paths transmitting a required flow when minimal paths are known.

• Journal of the Korean Data and Information Science Society
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• v.2
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• pp.11-21
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• 1991

A different approach to the evaluation of mean residual life function under the random censorship model is presented. For small sample sizes, the performances between the proposed estimator and other estimators for men residual life function are compared in terms of bias and mean square error via a Monte Carlo study.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.04a
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• pp.1067-1070
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• 2000

본 연구에서는 다양한 자격 시험 응시자들이 웹을 이용하여 시험을 보고, 실시간에 성적 및 통계자료 분석 결과를 확인할 수 있으며, 틀린 문항에 대해서 스스로 심화 학습을 할 수 있도록 인터넷을 이용한 온라인 시험 및 학습 평가 시스템을 제안하고자 한다. 제안된 온라인 학습 평가 시스템은 각 분야에서 다양하게 응용할 수 있으며, 앞으로의 인터넷 활용도가 높아지면서 새로운 형태의 학습 방법으로 자리잡을 것이다.