• 한국지반공학회논문집
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• 제18권5호
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• pp.271-280
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• 2002

본 연구에서는 사면안정해석 수행과정에서 입력되는 지반강도정수의 불확실성이 최소 신뢰성을 갖는 임계 활동면의 추적에 미치는 영향을 정량화하기 위한 확률론적 사면안정해석기법을 소개하였다. 일반적인 공사 현장에서 실무자가 상당한 양의 실내 및 현장 시험을 통해 얻어질 수 있는 지반강도정수의 다양한 통계.확률적 정보를 항상 확보하여 그것들을 상당한 수준의 통계적 지식을 가지고 자유스럽게 이용하는 것은 현실적으로 불가능하다. 따라서 본 연구에서는 실무자가 쉽게 확률적인 개념을 이해하면서 사면안정해석을 수행할 수 있도록 기존의 결정론적 사면안정해석 기법에 공학적 확률해석 기법을 결합시키는 방안을 제시하였다. 미 공병단에서 개발한 UTEXAS 3라는 범용 사면안정 해석 프로그램을 이용하여 본 연구는 파괴확률 또는 신뢰지수라는 관점에서 제안한 확률론적 사면안정해석기법의 결과들을 도출하였다. 본 확률론적 사면안정해석기법은 사면안정의 안전율만을 고려하는 기존의 결정론적 사면해석 기법들 보다 더욱 종합적으로 사면안정의 신뢰성에 대한 결과를 제시하는 것으로 나타났다.

• Ecology and Resilient Infrastructure
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• 제11권2호
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• pp.55-64
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• 2024

사전재해영향성 평가제도는 재해예방 차원의 절차로서 종합적이고 체계적인 개발사업을 위하여 2005년 도입되었다. 하지만, '재해영향성평가 실무지침'에 의거 제주도의 경우 수문지질학적 특성으로 인하여 홍수량 산정에 따른 확률강우량 산정 시 일반적인 방법이 아닌 고도반영이 가능한 등우선에 의한 확률강우량을 산정하도록 명시되어 있다. 하지만, 제주도의 경우 한라산을 중심으로 형성되어 있지만, 한라산 정상에 무인기상관측소(AWS)가 3개소 위치하고 있으며, 타 시·도 보다 기상관측소가 조밀하게 위치하고 있어 소규모 사업지구의 홍수량 산정 시 우량관측소의 확률강우량을 적용하거나 Thiessen 방법을 이용하는 일반적인 방법을 적용하더라도 무리가 없을것으로 판단된다. 따라서, 본 연구는 제주도내 사전재해영향성 평가제도의 적용에 있어 일반적인 우량관측소의 확률강우량과 등우선에의한 지점확률강우량을 비교·분석하여 그에 따른 영향성을 검토하였다.

• 한국산업융합학회 논문집
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• 제23권5호
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• pp.799-807
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• 2020

This paper deals with identification of probabilistic design using reliability based robust optimization in structure design of automatic salt collector. The thickness sizing variables of main structure member in the automatic salt collector were considered the random design variables including the uncertainty of corrosion that would be an inevitable hazardousness in the saltern work environment. The probabilistic constraint functions were selected from the strength performances of the automatic salt collector. The reliability based robust optimum design problem was formulated such that the random design variables were determined by minimizing the weight of the automatic salt collector subject to the probabilistic strength performance constraints evaluating from reliability analysis. Mean value reliability method and adaptive importance sampling method were applied to the reliability evaluation in the reliability based robust optimization. The three sigma level quality was considered robustness in side constraints. The probabilistic optimum design results according to the reliability analysis methods were compared to deterministic optimum design results. The reliability based robust optimization using the mean value reliability method showed the most rational results for the probabilistic optimum structure design of the automatic salt collector.

• Communications for Statistical Applications and Methods
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• 제11권1호
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• pp.49-58
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• 2004

In this talk we proposed an asymptotic test for dimensionality in the latent variable model for probabilistic principal component analysis with missing values at random. Proposed algorithm is a sequential likelihood ratio test for an appropriate Normal latent variable model for the principal component analysis. Modified EM-algorithm is used to find MLE for the model parameters. Results from simulations and real data sets give us promising evidences that the proposed method is useful in finding necessary number of components in the principal component analysis with missing values at random.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1466-1483
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• 2008

This paper discusses the development of an up-to-date computerized CPT (Cone Penetration Test) based soil engineering classification system to provide geotechnical engineers with a handy tool for their daily design activities. Five CPT soil engineering classification systems are incorporated in this effort. They include the probabilistic region estimation and fuzzy classification methods, both developed by Zhang and Tumay, the Schmertmann, the Douglas and Olsen, and the Robertson et al. methods. In the probabilistic region estimation method, a conformal transformation is used to determine the soil classification index, U, from CPT cone tip resistance and friction ratio. A statistical correlation is established between U and the compositional soil type given by the Unified Soil Classification System (USCS). The soil classification index, U, provides a soil profile over depth with the probability of belonging to different soil types, which more realistically and continuously reflects the in-situ soil characterization, which includes the spatial variation of soil types. The CPT fuzzy classification on the other hand emphasizes the certainty of soil behavior. The advantage of combining these two classification methods is realized through implementing them into visual basic software with three other CPT soil classification methods for friendly use by geotechnical engineers. Three sites in Louisiana were selected for this study. For each site, CPT tests and the corresponding soil boring results were correlated. The soil classification results obtained using the probabilistic region estimation and fuzzy classification methods are cross-correlated with conventional soil classification from borings logs and three other established CPT soil classification methods.

• Kyungpook Mathematical Journal
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• 제43권4호
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• pp.593-604
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• 2003

In this paper we introduce the integral type Lupas-$B{\acute{e}}zier$ operator $\tilde{B}_{n,{\alpha}}$, which is a new approximation operator of probabilistic type. We study the rate of pointwise convergence of the operators $\tilde{B}_{n,{\alpha}}$ for local bounded functions and get an asymptotically estimate by means of some methods and techniques of probability theory.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.855-858
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• 1988

Two methods for probabilistic maintenance scheduling are developed and compared ; one with operation and supplied-shortage cost and other with risk level of LOLP. Based on the real economic power dispatch, quadratic optimal maintenance conditions are obtained and simple amtrix equations are suggested for solutions. Both methods are compared in a sample system of 26,000 [MW] peak and 32,000 [MW] generation capacity.

• 한국군사과학기술학회지
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• 제16권5호
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• pp.631-638
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• 2013

The probabilistic fatigue life analysis is one of the common methods to account the uncertainty of parameters on the structural failure. Frequently, the Bayesian approach has been demonstrated as a proper method to show the uncertainty of parameters. In this work, the application of probabilistic fatigue life prediction method for the aircraft structure was studied. This effort was conducted by using the PoF(Probability of Failure) based on Bayesian approach. Furthermore, numerical example was carried out to confirm the validation of the suggested approach. In conclusion, it was shown that the Bayesian approach can calculate the probabilistic fatigue lives and the quantitative value of PoF effectively for the aircraft structural component. Moreover the calculated probabilistic fatigue lives can be utilized to determine the optimized inspection period of aircraft structures.

• 한국해양공학회지
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• 제19권1호
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• pp.26-32
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• 2005

Recent earthquakes, measuring over a magnitude of 5.0, on the eastern coast of Korea, have aroused interest in earthquake analyses and the seismic design of caisson-type breakwaters. Most earthquake analysis methods, such as equivalent static analysis, response spectrum analysis, nonlinear analysis, and capacity analysis, are deterministic and have been used for seismic design and performance evaluation of coastal structures. However, deterministic methods are difficult for reflecting on one of the most important characteristics of earthquakes, i.e. the uncertainty of earthquakes. This paper presents results of probabilistic seismic hazard assessment(PSHA) of an actual caisson-type breakwater, considering uncertainties of earthquake occurrences and soil properties. First, the seismic vulnerability of a structure and the seismic hazard of the site are evaluated, using earthquake sets and a seismic hazard map; then, the seismic risk of the structure is assessed.

• 한국항행학회논문지
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• 제1권1호
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• pp.35-46
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• 1997

다중 표적의 추적은 과거 10여년 동안 레이다 용용분야에서 큰 주목을 받아 왔으며 많은 학술회의와 논문발표의 중심 과제가 되어왔다. 이 문제를 해결하기 위하여 여러 가지 추적방식들이 제시되어 왔다. 그 중 대표적인 것으로는 Nearest Neighbor (NN) 방식에 의한 비확률적인 짝배정(association) 방법과 확률적인 표적모형에 기초한 Multiple Hypothesis Test (MHT) 방식 및 Joint Probabilistic Data Association (JPDA) 방식으로 대별할 수 있다. 이러한 여러 가지 방식들은 각기 그 장점 및 단점을 가지게 되어 계산속도나 표적의 추적정확도에 있어서 큰 차이를 나타내게 된다. 본 논문에서는 NN방식, MHT 방식 및 JPDA 필터에 기초한 세 가지 추적 알고리듬을 비교하고, 시뮬레이션을 통하여 다중 기동 표적에 대하여 그 추적성능을 분석한다.