• 한국초등수학교육학회지
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• 제12권1호
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• pp.79-100
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• 2008

Freudenthal은 수학적 개념을 가장 수학답게 가르치는 것, 그럼으로써 창의성을 기를 수 있게 하는 것은 어떤 수학적 개념이나 원리의 역사적인 수학화 과정을 재현하는 것이 되며, 이러한 역사적인 수학화를 교실에서 재현하는 방법을 '재발명 방법(reinvention method)'이라고 하였다. 이에 본 연구에서는 재발명 방법에 관한 이론들을 종합 분석하여, 효과적인 확률 개념 지도를 위해 제7차 초등 수학 교과서를 재구성해보고, 재구성한 내용을 직접 교수 실험함으로써 그 효과를 검증하고자 한다. 실험에 앞서 문헌 연구를 통해 재발명 방법에 대한 선행 연구를 종합 분석하면서 그와 대비되는 구상화 방법까지 고찰하였다. 현행 제7차 초등 수학 교과서를 면밀히 분석한 결과 현재 수학교과서의 확률 단원은 형식화를 강조하고 있고, 다루고 있는 확률 개념이 한정되어 있으며, 확률을 표현하는 방법 또한 분수로 제한하고 있음을 확인하였다. 이에 다양성과 현실 맥락을 주요 방향으로 하여 확률 단원 전체를 재구성하여 실험반에 적용하였다. 수업 결과 재발명 방법을 통해 학습을 진행하는 것이 학습자의 확률 개념을 형성하는 데 효과적이었으며, 다양한 표현 양식은 학습자의 확률에 대한 이해도를 높일 수 있는 것으로 나타났다.

• Asia-Pacific Journal of Atmospheric Sciences
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• 제54권4호
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• pp.623-637
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• 2018

This study investigates the effects of horizontal resolution, cumulus parameterization scheme (CPS), and probability forecasting on precipitation forecasts over the Korean Peninsula from 00 UTC 15 August to 12 UTC 14 September 2013, using the limited-area ensemble prediction system (LEPS) of the Korea Meteorological Administration. To investigate the effect of resolution, the control members of the LEPS with 1.5- and 3-km resolution were compared. Two 3-km experiments with and without the CPS were conducted for the control member, because a 3-km resolution lies within the gray zone. For probability forecasting, 12 ensemble members with 3-km resolution were run using the LEPS. The forecast performance was evaluated for both the whole study period and precipitation cases categorized by synoptic forcing. The performance of precipitation forecasts using the 1.5-km resolution was better than that using the 3-km resolution for both the total period and individual cases. The result of the 3-km resolution experiment with the CPS did not differ significantly from that without it. The 3-km ensemble mean and probability matching (PM) performed better than the 3-km control member, regardless of the use of the CPS. The PM complemented the defect of the ensemble mean, which better predicts precipitation regions but underestimates precipitation amount by averaging ensembles, compared to the control member. Further, both the 3-km ensemble mean and PM outperformed the 1.5-km control member, which implies that the lower performance of the 3-km control member compared to the 1.5-km control member was complemented by probability forecasting.

• 한국수학교육학회지시리즈A:수학교육
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• 제42권2호
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• pp.203-218
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• 2003

The purpose of this study is to see what the essential characteristics are in teaching probability and statistics among various mathematical fields. we also tried to connect the study of probability and statistics education with what is needed for a science be synthetic to have its own identity as a unique research field. Since we searched for the future direction of the pedagogic study in the probability and statistics we first selected papers on probability and statistics published in (Series A), the Journal of Korea Society of Mathematical Education, and establish the following research questions. What kinds of characteristics can be found when papers on probability and statistics published in (Series A) are classified into low categories; contents of probability and statistics education, research method of the mathematics education, methods of teaming and teaching, and finally measurements and evaluation\ulcorner We classified papers into two kinds. One is related to the educational contents, consisting of the methods of learning and teaching, and of the measurement and evaluation. The other is reined to the methods of research, which is not a part of the educational curriculum but is essential for establishing the identity of mathematics education. According to the periods, papers on the curricular contents in 1960s were influenced by the New Mathematics, and papers on the curricular contents in 1980s were influenced by 'back to basic'. In 1990s, papers on methods of learning and teaching, and measurement md evaluation were increasing in number. Besides, (series A) from the Journal of Korea Society of Mathematical Education covers contents, methods of Loaming and teaching, and measurement and evaluation. And when I examined the papers on the contents of textbook of a junior high school related to the probability and statistics education and on methods of learning and teaching, 1 found that those papers occupy 1.84% in . When it comes to the methods of loaming and teaching, most of studies in (series A) are about application of concrete implement like experiment and practical application of computer programs, Through this study, I found that over-all and more active researches on probability and statistics are required and that the studies about methods of loaming and teaching must be made in diverse directions. It is needed that how students recognize probability and statistics, connection, communication and representation in probability and statistics context, too. (series A) does not have papers on methods of study. Mathematics pedagogy is a mixture of various studies - mathematical psychology, mathematical philosophy, the history of mathematics and Mathematics. So If there doesn't exist a proper method of study adequate in the situation for the mathematics education the issue of mathematics pedagogy might be taken its own place by that of other studies'. We must search for the unique method of study fur mathematics education so that mathematics pedagogy has its own identity as a study. The study concerning this aspect is needed.

• 한국산림과학회지
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• 제58권1호
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• pp.48-53
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• 1982

현행(現行)의 형태학적수목분류법(形態學的樹木分類法)에 계획적특성(計劃的特性)을 이용(利用)한 소위(所謂) 판별분석법(判別分析法)에 의(依)할 독일(獨逸)가문비(Picea abies(L.) Karsten)와 종비나무(樅榧)(Picea koraiensis Nak.)와의 분류시험(分類試驗)을 실시(實施)하고 그 결과(結果)를 다음과 같이 요약(要約)한다. 1) 본(本) 시험(試驗)에서 얻은 판별식(判別式)과 판별영역(判別領域)은, Z(x)=Z($x_1,\;x_2$)=$0.000379x_1+0.004354x_2-0.311061$ 또는 Z(x)=Z($x_1,\;x_2$)=$0.000379(x_1-60.4428)+0.004354(x_2-66.1851)$, $$R_1=\{x{\mid}0.000379x_1+0.004354x_2-0.311061{\geq_-}0\}$$, $R_2$={$x{\mid}0.000379x_1+0.004354x_2-0.311061$ <0)} 또는 $$R_1=\{x{\mid}0.000379(x_1-60.4428)+0.004354(x_2-66.1851){\geq_-}0%\}$$, $R_2$={$x{\mid}0.000379(x_1-60.4428)+0.004354(x_2-66.1851)$ <0}. 2) 위의 판별영역(判別領域)에 의(依)한 오판율(誤判率)(오분류확율(誤分類確率))은, P($2{\mid}1$)=($P1{\mid}2$)=0.444로서, P($2{\mid}1$)와 P($P1{\mid}2$)의 동시오판율(同時誤判率)은 P=44.4%. 3) 본(本) 시험(試驗)에서 얻은 판별식(判別式)에 의(依)한 오판율(誤判率)은 상당(相當)히 높게 나타났지만 그의 정도(精度)보다는 오히려 판별(判別)에 대(對)한 신뢰도(信賴度)를 알 수 있다는데 보다 큰 의의(意義)가 있는 것으로 사료(思料)된다.

• 한국수정란이식학회지
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• 제28권3호
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• pp.207-213
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• 2013

This study was carried out to examine a molecular marker system for parentage test in Jeju Black cattle (JBC). Based on the preliminarily studies, we finally selected for construction of a novel genetic marker system for molecular traceability, identity test, breed certification, and parentage test in JBC and its related industrial populations. The genetic marker system had eight MS markers, five indel markers, and two single nucleotide polymorphisms (SNPs; g.G299T and g.del310G) within MC1R gene which is critical to verify the breed specific genotypes for coat color of JBC differing from those of exotic black cattle breeds such as Holstein and Angus. The results showed lower level of a combined non-exclusion probability for second parent (NE-P2) of $4.1202{\times}10^{-4}$ than those previously recommended by International Society of Animal Genetics (ISAG) of $5.000{\times}10^{-4}$ for parentage, and a combined non-exclusion probability for sib identity (NE-SI) of $2.679{\times}10^{-5}$. Parentage analysis has been successfully identified the JBC offspring in the indigenous population and cattle farms used the certified AI semens for production using the JBC-derived offspring for commercial beef. This combined molecular marker system will be helpful to supply genetic information for parentage test and traceability and to develop the molecular breeding system for improvement of animal productivity in JBC population.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.690-693
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• 2005

In this paper, probabilistic distribution of fatigue life of chassis component is determined statistically by applying the design of experiments and the Pearson system. To construct $p-\varepsilon-N$ curve, the case that fatigue data are random variables is attempted. Probabilistic density function(p.d.f) for fatigue life is obtained by design of experiment and using this p.d.f fatigue reliability about any aimed fatigue life can be calculated. Lower control arm and rear torsion bar of chassis component are selected as examples for analysis. Component load histories, which are obtained by multi-body dynamic simulation for Belsian load history, are used. Finite element analysis are performed using commercial software MSC Nastran and fatigue analysis are performed using FE Fatigue. When strain-life curve itself is random variable, probability density function of fatigue life has very little difference from log-normal distribution. And the case of fatigue data are random variables, probability density functions are approximated to Beta distribution. Each p.d.f is verified by Monte-Carlo simulation.

• 한국통신학회논문지
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• 제28권9C호
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• pp.884-890
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• 2003

본 논문에서는 화자 독립 시스템에서 필요한 화자 적응 방법에 관해 연구하였다. 훈련에 참여하지 않은 새로운 화자에 대해서 bigram과 back-off bigram, MAP와 MLLR의 결과를 비교해 보았다. back-off bigram은 훈련중 나타나지 않은 bigram 확률을 unigram과 back-off 가중치를 적용하므로 bigram 확률 값에 약간의 가중치를 더하는 효과를 가져온다. 음성의 특징 파라미터로는 12차의 MFCC와 log energy, 1차 미분, 2차 미분을 사용하여 총 39차의 특징 벡터를 사용하였다. 인식 실험을 위해 CHMM, 삼중음소(tri-phones)의 인식 단위, 그리고 bigram과 back-off bigram의 언어 모델을 사용한 시스템을 구성하였다.

• 한국정밀공학회지
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• 제24권2호
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• pp.110-117
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• 2007

In this paper, probabilistic distribution of chassis component fatigue life is determined statistically by applying the design of experiments and the Pearson system. To construct p - ${\varepsilon}$ - N curve, the case that fatigue data are random variables is attempted. Probabilistic density function (p.d.f) for fatigue life is obtained by the design of experiment and using this p.d.f fatigue reliability, any aimed fatigue life can be calculated. Lower control arm and rear torsion bar of chassis components are selected as examples for analysis. Component load histories which are obtained by multi-body dynamic simulation for Belsian load history are used. Finite element analysis is performed by using commercial software MSC Nastran and fatigue analysis is performed by using FE Fatigue. When strain-life curve itself is random variable, the probability density function of fatigue life has very little difference from log-normal distribution. And the cases of fatigue data are random variables, probability density functions are approximated to Beta distribution. Each p.d.f is verified by Monte-Carlo simulation.

• 한국CDE학회논문집
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• 제18권5호
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• pp.359-366
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• 2013

In the lower arm design process, a tolerance optimization of the variance of design variables should be preceded before manufacturing process, since it is very cost-effective compared to a strict management of tolerance of products. In this study, a design of experiment (DOE) based on response surface model (RSM) was carried out to find optimized design variables of the lower arm, which can meet a given requirement of probability constraint for the process capability index (Cpk) of the weight and maximum stress. Then, the design space was explored by using the central composite design method, in which the 2nd order Taylor expansion was applied to predict a standard deviation of the responses. The optimal solutions satisfying the probability constraint of the Cpk were found by considering both of the mean value and the standard deviation of the design variables.

• 터널과지하공간
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• 제11권2호
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• pp.156-166
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• 2001

균열암반에서의 지하수유동 모사를 위한 추계적 연속테 모델링 기법이 개발되었다. 추계적연속체 모델은 균열수의 제한을 가지는 개별균열연결망 모델의 단점을 극복할 수 있다. 뿐만 아니라 개별균열연결망 모델에서 가능한 확률론적 해석과 전도성이 큰 균열을 통한 지하수 유동을 근접하게 모사할 수 있는 장점을 가진다. 추계적연속체 모델은 개별균열연결망 모델에 근거하여 생성된다. 개별균열연결망 모델은 일정크기의 소블록으로 나누어지며 각 소블록 투수계수의 확률밀도함수와 베리오그램 함수로부터 추계적연속체 모델에서의 투수계수의 공간적 분포를 정의할 수 있다. 이 연구에서 추계적연속체 모델과 개별균열연결망 모델의 적합성을 보여 주기 위하여 수치실험을 통하여 지하수 유동 이동시간을 계산하고 상호 비교하였다. 그리고 추계적연속체 모델은 방사성폐기물 처분장의 확률론적 안전성 펑가를 위해 필요한 지하수 유동속도의 확률분포를 제공할 수 있는 모델임을 제시할 수 있었다.