• Journal of Wetlands Research
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• v.20 no.2
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• pp.105-115
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• 2018

The frequency analysis of hydrometeorological data is one of the most important factors in response to natural disaster damage, and design standards for a disaster prevention facilities. In case of frequency analysis of hydrometeorological data, it assumes that observation data have statistical stationarity, and a parametric method considering the parameter of probability distribution is applied. For a parametric method, it is necessary to sufficiently collect reliable data; however, snowfall observations are needed to compensate for insufficient data in Korea, because of reducing the number of days for snowfall observations and mean maximum daily snowfall depth due to climate change. In this study, we conducted the frequency analysis for snowfall using the Bootstrap method and SIR algorithm which are the resampling methods that can overcome the problems of insufficient data. For the 58 meteorological stations distributed evenly in Korea, the probability of snowfall depth was estimated by non-parametric frequency analysis using the maximum daily snowfall depth data. The results of frequency based snowfall depth show that most stations representing the rate of change were found to be consistent in both parametric and non-parametric frequency analysis. According to the results, observed data and Bootstrap method showed a difference of -19.2% to 3.9%, and the Bootstrap method and SIR(Sampling Importance Resampling) algorithm showed a difference of -7.7 to 137.8%. This study shows that the resampling methods can do the frequency analysis of the snowfall depth that has insufficient observed samples, which can be applied to interpretation of other natural disasters such as summer typhoons with seasonal characteristics.

• The Transactions of the Korea Information Processing Society
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• v.3 no.7
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• pp.1792-1802
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• 1996

The analysis of prepositional phrases in English-to Korean machine translation has problem on the PP-attachment resolution, semantic analysis, and acquisition of information. This paper presents an analysis system for prepositional phrases, which solves the problem. The analysis system consists of the PP-attachment resolution hybrid system, semantic analysis system, and semantic feature generator that automatically generates input information. It provides objectiveness in analyzing prepositional phrases with the automatic generation of semantic features. The semantic analysis system enables to generate natural Korean expressions through selection semantic roles of prepositional phrases. The PP-attachment resolution hybrid system has the merit of the rule-based and neural network-based method.

• Journal of the Korean Geotechnical Society
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• v.23 no.11
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• pp.109-117
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• 2007

Uncertainty is pervasive in rock slope stability analysis due to various reasons and subsequently it may cause serious rock slope failures. Therefore, the importance of uncertainty has been recognized and subsequently the probability theory has been used to quantify the uncertainty since 1980's. However, some uncertainties, due to incomplete information, cannot be handled satisfactorily in the probability theory and the fuzzy set theory is more appropriate for those uncertainties. In this study the random variable is considered as fuzzy number and the fuzzy set theory is employed in rock slope stability analysis. However, the previous fuzzy analysis employed the approximate method, which is first order second moment method and point estimate method. Since previous studies used only the representative values from membership function to evaluate the stability of rock slope, the approximated analysis results have been obtained in previous studies. Therefore, the Monte Carlo simulation technique is utilized to evaluate the probability of failure for rock slope in the current study. This overcomes the shortcomings of previous studies, which are employed vertex method. With Monte Carlo simulation technique, more complete analysis results can be secured in the proposed method. The proposed method has been applied to the practical example. According to the analysis results, the probabilities of failure obtained from the fuzzy Monte Carlo simulation coincide with the probabilities of failure from the probabilistic analysis.

• The Korean Journal of Applied Statistics
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• v.8 no.2
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• pp.179-185
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• 1995

We present comprehensive mechanical interpretations for probabilities of a cubotahedral die.

• Journal of Welding and Joining
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• v.25 no.6
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• pp.27-29
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• 2007

GMA 용접 시스템을 시뮬레이션 하기 위한 요소 기술과 문제점에 대하여 간단하게 설명하였다. 현재까지의 연구 결과로부터 GMA 용접 시스템을 해석하는데 필요한 원리 및 기본 방정식은 거의 알려진 상태이지만, 이와 같은 시뮬레이션은 이상적인 조건에서 계산한 결과로서 실제와는 차이가 발생한다. 이와 같은 오차는 실험을 통하여 지속적으로 수정 및 보완되어야 시뮬레이션의 정확도를 향상시킬 수 있으며, 향후 시뮬레이션이 용접 생산성과 품질을 향상시키는 도구로 활용될 수 있기를 기대한다.

• Computational Structural Engineering
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• v.4 no.2
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• pp.111-117
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• 1991

The analysis method calculating the mean and standard deviation for the eigenvalue of complicated structures in which the limit state equation is implicitly expressed is formulated and applied to the buckling analysis by combining probabilistic finite element method with direct differential method which is a kind of sensitivity analysis technique. Also, the probability of buckling failure is calculated by combining classical reliability techniques such a MVFOSM and AFOSM. As random variables external load, elastic modulus, sectional moment of inertia and member length are chosen and Parkinson's iteration algorithm in AFOSM is used. The accuracy of the results by this study is verified by comparing the results with the crude Monte Carlo simulation and Importance Sampling Method. Through the case study of some structures the important aspects of buckling reliability analysis are discussed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.5
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• pp.481-489
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• 2011

In this paper presents new force method by using singular value decomposition. The existing force method has some advantages about analysis of truss structures such as it is easier basic concept than finite element method, which apply to analyze truss structures. However, this method has complex formulation for analysis. Therefore, in this study proposes new force method using singular value decomposition, which is both having easy basic concept and simple computation than existing force method. The proposed method is illustrated through numerical examples.

• Journal of Korean Philosophical Society
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• v.117
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• pp.137-160
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• 2011

This article aims to elucidate the meaning of Conservativeness and Progress through the hermeneutical discussion about Tradition and Ideology. This study is concerned with Contemporary Hermeneutics, especially H.G. Gadamer, J. Habermas, and P. Ricoeur's Hermeneutics. We will find conservative aspects of Gadamer's Hermeneutics and progressive aspects of Habermas's Hermeneutics through debate on Hermeneutics between Gadamer and Habermas. And we will deal with the meaning of the concept of Conservativeness and Progress in context of Hermeneutics. Then, we will find the difference and common feature, the uppermost limits between Gadamer and Habermas's Hermeneutics in terms of Ricoeur's view. In this context, we will lastly pursue a way of solution about problem of Idea, that is Conservativeness vs Progress through hermeneutical Synthesis.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.271-274
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• 2009

강관의 내부에 콘크리트를 충전한 콘크리트 충전 강관 구조(CFT 구조, Concrete Filled Steel Tubular Structure)는 강재와 콘크리트의 단점을 상호 보완하고, 장점을 극대화 할 수 있다는 이점 때문에 최근 실제 구조물의 시공에 적용하는 사례가 증가하고 있는 추세이다. 이와 같은 CFT 거더의 장점을 살리면서 CFT 거더보다 더 뛰어난 경제적, 구조적 효율성을 얻기 위해 기존의 CFT 구조에 아치 형식과 프리스트레스를 도입한 CFTA(Concrete Filled and Tied Tubular Arch) 거더에 관한 연구가 현재 진행중이다. 본 연구에서는 CFTA 거더의 현장 실험과의 비교를 위해 ABAQUS 6.5-1을 이용하여 CFTA 거더의 유한요소 해석을 수행하였고, 이를 바탕으로 구조물의 선형거동을 분석하였다. 또한 구조물의 위험도 분석을 위해 본 구조물의 가장 약점으로 지적되고 있는 외부로 노출되어 있는 긴장재의 차량 충돌에 의한 사고를 가정하여 이를 고려한 유한 요소 해석을 수행하여 CFTA 구조물의 동적 및 정적 안전성 평가를 수행하고 그 결과를 분석하였다.

• 전기의세계
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• v.39 no.3
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• pp.32-38
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• 1990

1960년대 후반 유한요소법인 전자장 수치해석에 응용되기 시작한 후 전기기기 특성해석, 성능예측 및 설계에 많은 도움을 주었다. 그동안 실제 모델에 응용된것은 거의가 2차원 문제에 국한되었다. 그러나, 최근 들어서는 각종 전기기기가 경량화, 소형화, 고효율화 됨에 따라 점차로 3차원 전자장 수치해석에 대한 요구가 급증하고 잇다. 앞서 언급한 바와 같이 유한요소법은 영역법의 일종으로 영역을 적절히 요소분할 하는데 어려움이 있다. 따라서 근래에 영역법의 문제점을 보완하기 위하여, 또한 영역법으 대용으로 경계법에 대한 연구가 점차로 증대되고 있다. 경계요소법은 주어진 지배방정식에 대한 Green 함수를 반드시 알아야만 하는 단점을 갖고 있으나 근래에 들어서는 광범위한 분야에 걸쳐 Grem함수가 이미 발전되어 있기 때문에 실제 응용에는 별 문제가 없으리라 생각된다.