• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1295-1299
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• 1990

A new method called random sampling method has been proposed for generation of binary random sequences. In this paper, a new concept, called merit factor Fn, is proposed for evaluating the randomness of the binary random sequences generated by the random sampling method. Using this merit factor Fn, some desirable conditions are investigated for uniform random numbers used in the random sampling method.

• Structural Engineering and Mechanics
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• 제57권2호
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• pp.369-387
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• 2016

In this work, random homogenization analysis for the effective thermal properties of a three-dimensional composite material with unidirectional fibers is presented by combining the equivalent inclusion method with Random Factor Method (RFM). The randomness of the micro-structural morphology and constituent material properties as well as the correlation among these random parameters are completely accounted for, and stochastic effective thermal properties as thermal expansion coefficients as well as their correlation are then sought. Results from the RFM and the Monte-Carlo Method (MCM) are compared. The impact of randomness and correlation of the micro-structural parameters on the random homogenized results is revealed by two methods simultaneously, and some important conclusions are obtained.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.979-983
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• 1989

This paper proposes a new concept, called merit factor Fr, for evaluating the randomness of binary random sequences. The merit factor Fr is obtained from the expected values of the autocorrelation function of the binary random sequence. Using this merit factor Fr, randomness of the binary random sequences generated by the random sampling method is evaluated.

• Journal of Power Electronics
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• 제10권1호
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• pp.51-57
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• 2010

This paper proposes a new random switching strategy using a DSP TMS320F2812 to reduce the harmonics spectra of single phase switched reluctance motors. The proposed method combines the random turn-on/off angle technique and the random pulse width modulation technique. A harmonic spread factor (HSF) is used to evaluate the random modulation scheme. In order to confirm the effectiveness of the proposed method an experiment was conducted. The experimental results show that the harmonic intensity of the output voltage for the proposed method is better than that for conventional methods.

• Communications for Statistical Applications and Methods
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• 제7권1호
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• pp.141-150
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• 2000

In this paper we propose a method of computing Bayes factor to detect an outlier in a random effects model. When no information is available and hence improper noninformative priors should be used Bayes factor includes the unspecified constants and has complicated computational burden. To solve this problem we use the fractional Bayes factor (FBF) of O-Hagan(1995) and the generalized Savage0-Dickey density ratio of Verdinelli and Wasserman (1995) The proposed method is applied to outlier deterction problem We perform a simulation of the proposed approach with a simulated data set including an outlier and also analyze a real data set.

• 한국터널지하공간학회 논문집
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• 제10권4호
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• pp.349-360
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• 2008

본 논문에서는 탄소성 유한요소해석 알고리즘과 연계한 확률장 생성기법과 근접터널 조건에서의 파괴확률을 분석하였다. 유한요소 해석을 위한 이산 확률장의 생성은 빠르고 정확하며 랜덤변수의 해상도를 자유롭게 조절할 수 있는 local average subdivision 기법을 사용하였으며 터널모델링을 위해 유한요소 크기와 형상 변화 등을 적절히 고려하여 지반물성치를 적용하는 방안을 제안하였다. 예제해석 조건에 대해 강도정수의 분산정도 및 공간상관길이에 따른 파괴확률을 파악하였으며 결정론적 안정성 해석결과 및 단일랜덤변수 해석결과와 비교하였다. 강도정수의 분산특성에 따라 강도감소기법에 의한 안전율과 단일랜덤변수 해석에 의한 파괴확률의 관계를 규명하였으며 확률유한요소 해석을 통해 공간상관길이가 파괴확률에 미치는 영향을 분석하였다. 이를 통해 강도감소기법에 의한 안전율과 분산계수로부터 단일랜덤변수에 의한 파괴확률을 도출할 수 있었으며 단일랜덤변수 해석결과가 근접터널의 실제적인 파괴확률을 과소평가 할 수 있음을 파악하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.208-213
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• 2004

Methods for estimation of the effective stress intensity factor range (${\Delta}K_{eff}$) are evaluated for narrow and wide band random loading crack growth test data of 2024-T351 aluminum alloy. Three methods of determining $K_{op}$, visual measurement, ASTM offset compliance method, and the neural network method proposed by Kang and Song, and three methods of estimating ${\Delta}K_{eff}$, conventional, the 2/PI0 and 2/PI methods proposed by Donald and Paris, are compared in a quantitative manner by using the results of fatigue crack growth life prediction under random loading. For all $K_{op}$ determination methods discussed, the 2/PI0 and 2/PI methods of estimating ${\Delta}K_{eff}$ provide better results than conventional method for narrow and wide band random loading data.

• 한국구조물진단유지관리공학회 논문집
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• 제5권1호
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• pp.169-175
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• 2001

Bridge load rating calculations provide a basis for determining the safe load capacity of bridge. Load rating requires engineering judgement in determining a rating value that is applicable to maintaining the safe use of the bridge and arriving at posting and permit decisions. Load testing is an effective means in calculating the rating value of bridge. In Korea, load carrying capacity of bridge is modified by response modification factor that is determined from comparisons of measured values and analysis results. The response modification factor may be corrupted by vehicle location error that is defined as the gap of test vehicle location between load testing and analysis. In this study, the effects of vehicle location error to structural response and response modification factor are investigated, and a new method for evaluating response modification factor is proposed. The random data analysis shows that the proposed method is less sensitive to vehicle location error than the present method.

• Journal of the Korean Data and Information Science Society
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• 제22권3호
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• pp.381-387
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• 2011

본 논문은 일원 확률모형의 가정하에 실험자료를 분석할 때 확률모형과 관련된 분산성분을 추정하는 문제를 다루고 있다. 분산성분의 추정방법으로 적률법을 이용하고 있다. 적률법을 이용할 때 필요한 두 가지 계산과정은 요인의 변동에 따른 제곱합과 제곱합의 기대값 계산이다. 제곱합의 계산으로 사영을 어떻게 이용하는 가를 논의하고 있다. 제곱합의 기대값 계산을 위해 분산성분의 계수로 관측되는 관련행렬의 고유근을 이용하는 방법을 다루고 있다. 분산성분의 적률추정량으로 사영과 고유근을 이용한 분산성분의 추정방법이 Hartley (1967)의 합성법보다 간편하고 효율적인 방법임을 논의하고 있다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2011년도 춘계학술대회
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• pp.695-699
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• 2011

The study presents an efficient design method of Venn Diagram that can be used when implementing the quality design of experiments based on generalizability theory. The paper examines four mixed and combined models that are designed by fixed factor, random factor, crossed factor and nested factor. The models considered in this research are $A^*{\times}B^*{\times}C$, (B: $A^*$)${\times}C$, $A{\times}B{\times}C$ and (B: A)${\times}C$.