• 제목/요약/키워드: Bayes theorem

검색결과 48건 처리시간 0.027초

ON-LINE ESTIMATION PROCEDURES OF DIGITAL FILTER TYPE FOR REVERBERATION CHARACTERISTICS IN CLOSED ACOUSTIC SYSTEMS BASED ON NOISY OBSERVATION

  • Hiromitsu, Seijiro;Ohta, Mitsuo
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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    • pp.680-685
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    • 1994
  • The acoustic phenomena in the actual sound systems involve a variety of compound problems. In this paper, the well-known Bayes' theorem is first employed and expanded into orthonormal and non-orthonomal series forms matched to the digital processing of lower and higher order statistical informations and the noisy observations. Proposed on-line algorithms of digital filter type are applied to the actual state estimation for a reverberation characteristics in a room under contamination of background noises.

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확률론적 기법을 이용한 탄산화 RC 구조물의 내구성 예측 (A Long-term Durability Prediction for RC Structures Exposed to Carbonation Using Probabilistic Approach)

  • 정현준;김규선
    • 한국구조물진단유지관리공학회 논문집
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    • 제14권5호
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    • pp.119-127
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    • 2010
  • 본 논문에서는 탄산화 콘크리트 구조물의 내구성을 예측하기 위한 새로운 접근 방법을 제시하였다. 제시된 예측 방법은, 새로운 계측 데이터가 있을 때 베이스 이론에 근거하여 지속적인 업데이팅이 가능하며 모델 매개변수의 확률론적인 특성이 고려된다. 탄산화 내구성 해석 모델의 절차는 라틴 하이퍼큐브 샘플 추출법(LHS)으로 간단하게 정리되고, 이를 통해 얻는 표본으로 결정된다. 이 방법은 콘크리트 구조물의 설계에 유용하게 사용될 수 있으며, 모니터링을 통한 콘크리트 구조물의 잔존수명을 예측할 수 있다. 본 논문에서 사전예측치는 탄산화에 노출된 국내 콘크리트 구조물 데이터(3700개 시편)를 이용하여 콘크리트 탄산계수의 확률 특성을 고려하여 나타내었으며, 우도함수는 현장 모니터링 데이터를 이용하였으며 사후예측치는 사전예측치와 우도함수를 조합하여 나타내었다. 또한, 몬테 카를로 시뮬레이션(MCS)과 LHS의 비교를 통하여 본 논문에서 수행된 LHS를 이용한 샘플링기법이 보다 효율적인 시뮬레이션 수행이 가능함을 확인하였다.

시스템의 치명도 분석을 위한 고장영향확률 정량화 방안 연구 (A Study on the Quantitative Determination of Failure Effect Probability for Criticality Analysis on System)

  • 이명석;최성대;허장욱
    • 한국기계가공학회지
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    • 제18권8호
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    • pp.31-37
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    • 2019
  • The inter-development of FMECA is very important to assess the effect of potential failures during system operation on mission, safety and performance. Among these, criticality analysis is a core task that identifies items with high risk and selects the analyzed objects as the key management targets and reflects their effects to the design optimization. In this paper, we analyze the theory related to criticality analysis following US military standard, and propose a method to quantify the failure effect probability for objective criticality analysis. The criticality analysis according to the US military standard depends on the subjective judgment of the failure probability. The methodology for quantifying the failure effect probability is presented by using the reliability theory and the Bayes theorem. The failure rate is calculated by applying the method to quantify failure effect probability.

퍼지 사전 모수에 관한 베이지안 가설검정 (Hypotheses testing of Bayes' theorem for fuzzy prior parameters)

  • 강만기;최규탁
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2005년도 추계학술대회 학술발표 논문집 제15권 제2호
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    • pp.205-208
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    • 2005
  • We have fuzzy hypotheses testing from Bayesian statistics with ideas from fuzzy sets theory to generalize Bayesian methods both for samples of fuzzy data and for prior distributions with non-precise parameters. Appling the principle of agreement index, the posterior odds ratio in the favor of hypotheses $H_0$ is equal to product of the fuzzy odds ratio and the fuzzy likelihood ratio. If the Posterior odds ratio exceeds the grade judgement, we accept the hypothesis $H_0$ for the degree.

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Understanding Bayesian Statistics

  • 정윤식
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2002년도 추계 학술발표회 논문집
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    • pp.61-68
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    • 2002
  • 통계학은 불확실성(uncertainty)에 대한 연구이다. 베이지안 통계 방법은 불확실성 아래서 통계 추론과 의사 결정 모두를 위한 완전한(complete) 패러다임을 제공한다. 베이지안 방법론은 합리적인 초기 정보와 결합하는 것을 가능하게 만들고, 전통적인 통계적 방법론에 의하여 직면하는 많은 어려움들을 풀 수 있는 coherent 방법론을 제공하면서 엄격한 수학적 기본에 근거하고 있다. 베이지안 패러다임은 일반적인 용어로써 확률이란 단어의 사용을 가장 잘 어울리게 하는 불확실성의 조건부 측도(conditional measure of uncertainty)로써 확률의 해석에 근거한다. 관심있는 것에 대한 통계적 추론은 증거의 관점에서 그 값에 대한 불확실성의 변형으로써 묘사되며, 베이즈 정리(Bayes' theorem)는 이러한 변형이 어떻게 만들어지는 가를 자세히 설명할 수 있다. 베이지안 방법들은 전통적인 통계적 방법론에 접근할 없는 복잡하고, 다양한 구조적 문제들에 응용할 수 있다.

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AzTEC Submillimeter Survey of Galaxies

  • Kim, Ki-Hun;Kim, Sung-Eun;AzTEC team, AzTEC team
    • 천문학회보
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    • 제35권2호
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    • pp.38.1-38.1
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    • 2010
  • We present the results of the survey for submillimeter galaxies in the MS0451 (04h 54m 10.8s, -03d 00m 57.0s) at z = 0.55 and PKS1138-262 (11h 40m 48.25s, -26d 29m 10.1s) at z = 2.16 with the 1.1mm bolometer array AzTEC at the James Clerk Maxwell Telescope. The samples were centered on a prominent large-scale structure overdensity. Submillimeter galaxies seem to be starburst galaxies at high redshift ($z\;\geq\;1$) with high starformation rates ($\sim1000M\odot\;yr^{-1}$) or active galactic nuclei (AGN). We have obtained AzTEC images using the AzTEC data reduction pipeline with the IDL language. Through a bayes' theorem, we determined the extragalaxy catalogue, containing the false-detection rate, completeness, flux deboosting correction, and the source positional uncertainty in this region. We compared the catalogue with HST, DSS, 2MASS observations.

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EVALUATION OF DIAGNOSTIC TESTS WITH MULTIPLE DIAGNOSTIC CATEGORIES

  • Birkett N.J.
    • 대한예방의학회:학술대회논문집
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    • 대한예방의학회 1994년도 교수 연수회(역학)
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    • pp.154-157
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    • 1994
  • The evaluation of diagnostic tests attempts to obtain one or more statistical parameters which can indicate the intrinsic diagnostic utility of a test. Sensitivity. specificity and predictive value are not appropriate for this use. The likelihood ratio has been proposed as a useful measure when using a test to diagnose one of two disease states (e.g. disease present or absent). In this paper, we generalize the likelihood ratio concept to a situation in which the goal is to diagnose one of several non-overlapping disease states. A formula is derived to determine the post-test probability of a specific disease state. The post-test odds are shown to be related to the pre-test odds of a disease and to the usual likelihood ratios derived from considering the diagnosis between the target diagnosis and each alternate in turn. Hence, likelihood ratios derived from comparing pairs of diseases can be used to determine test utility in a multiple disease diagnostic situation.

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Review on the Application of Statistical Methods to Maritime Traffic Safety Assessment

  • Gong, In-Young
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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    • pp.35-40
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    • 2006
  • For the maritime traffic safety assessment of vessels navigating in harbor or fairway, simulation techniques by using shiphandling simulator system have been traditionally used. When designing the simulation experiments and when analyzing the simulation results, however, there has been a little systematic method. Ship-handling simulations can be regarded as a kind of statistical experiment by using ship-handling simulator system, which means that shiphandling simulation conditions should be designed statistically and that the simulation results should be statistically analyzed as well. For the safe and economic design of harbor and fairway, reasonable decisions based upon the scientific analysis of shiphandling simulation results are indispensable. In this paper, various statistical methods, such as Bayes theorem, statistical hypothesis testing, and probability distributions, are reviewed with a view to application to maritime traffic safety assessment. It is expected that more reasonable decisions on harbor and fairway design can be made from shiphandlers' view point by using statistical methods.

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전동차 출입문제어 계전기의 신뢰도예측을 통한 적정 교체주기 연구 (A Study on Evaluation of Optimal Replacement Period by Reliability Prediction for the Door Control Relay of EMU)

  • 한재현;김종운;구정서
    • 조명전기설비학회논문지
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    • 제28권7호
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    • pp.34-40
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    • 2014
  • In this paper, we want to know the optimal replacement cycle(time) for this study was performed. The optimal preventive replacement age can be fond by finding the value of time that minimizes the cost function(model of Barlow and Jardine). In addition, The reliability of the relay according to the service environment were studied. The use of the exchange relay period is longer, and maintenance cost rate(per hour) may increase, and also the reliability may cause a decline. In addition, considering the preventive maintenance and purchase order, a representative relay(RAX-L440-A type) life was calculated.

베이지안 분류 기반의 입 모양을 이용한 한글 모음 인식 시스템 (Recognition of Korean Vowels using Bayesian Classification with Mouth Shape)

  • 김성우;차경애;박세현
    • 한국멀티미디어학회논문지
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    • 제22권8호
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    • pp.852-859
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    • 2019
  • With the development of IT technology and smart devices, various applications utilizing image information are being developed. In order to provide an intuitive interface for pronunciation recognition, there is a growing need for research on pronunciation recognition using mouth feature values. In this paper, we propose a system to distinguish Korean vowel pronunciations by detecting feature points of lips region in images and applying Bayesian based learning model. The proposed system implements the recognition system based on Bayes' theorem, so that it is possible to improve the accuracy of speech recognition by accumulating input data regardless of whether it is speaker independent or dependent on small amount of learning data. Experimental results show that it is possible to effectively distinguish Korean vowels as a result of applying probability based Bayesian classification using only visual information such as mouth shape features.