• 제목/요약/키워드: Probabilistic Prediction

검색결과 280건 처리시간 0.03초

Relevance vector based approach for the prediction of stress intensity factor for the pipe with circumferential crack under cyclic loading

  • Ramachandra Murthy, A.;Vishnuvardhan, S.;Saravanan, M.;Gandhic, P.
    • Structural Engineering and Mechanics
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    • 제72권1호
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    • pp.31-41
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    • 2019
  • Structural integrity assessment of piping components is of paramount important for remaining life prediction, residual strength evaluation and for in-service inspection planning. For accurate prediction of these, a reliable fracture parameter is essential. One of the fracture parameters is stress intensity factor (SIF), which is generally preferred for high strength materials, can be evaluated by using linear elastic fracture mechanics principles. To employ available analytical and numerical procedures for fracture analysis of piping components, it takes considerable amount of time and effort. In view of this, an alternative approach to analytical and finite element analysis, a model based on relevance vector machine (RVM) is developed to predict SIF of part through crack of a piping component under fatigue loading. RVM is based on probabilistic approach and regression and it is established based on Bayesian formulation of a linear model with an appropriate prior that results in a sparse representation. Model for SIF prediction is developed by using MATLAB software wherein 70% of the data has been used for the development of RVM model and rest of the data is used for validation. The predicted SIF is found to be in good agreement with the corresponding analytical solution, and can be used for damage tolerant analysis of structural components.

단어 기반의 확률 모델을 이용한 단백질 기능 예측 (Function Prediction of Gene products by Term based Probabilistic Model)

  • Park, Dae-Won;Kwon, Hyuk-Chul
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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    • pp.73-78
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    • 2003
  • 유전 연구를 통해 밝혀지고 있는 단백질은 각각의 기능적 특성을 가지고 서로 영향을 주고받으며 상호 작용한다. 단백질의 기능적 특성은 생물체에서는 단백질이 나타내는 기능으로 단백질 이름은 이들 단백질의 기능을 정확히 나타낼 수 있도록 붙여진다. 기능적 특성에 의해 명명된 단백질은 단백질을 구성하는 단어도 단백질과 유사한 기능 특성을 가질 가능성이 높다. 이는 텍스트 기반의 연구에서 단어가 가지는 중요성에서 비롯된다. 본 논문에서는 단백질을 구성하는 단어들을 단백질의 기능적 특성으로 분류하고, 이 기능분포에 의해서 단백질의 기능을 역으로 예측하고 판단하고자 하였다.

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Time-variant structural fuzzy reliability analysis under stochastic loads applied several times

  • Fang, Yongfeng;Xiong, Jianbin;Tee, Kong Fah
    • Structural Engineering and Mechanics
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    • 제55권3호
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    • pp.525-534
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    • 2015
  • A new structural dynamic fuzzy reliability analysis under stochastic loads which are applied several times is proposed in this paper. The fuzzy reliability prediction models based on time responses with and without strength degeneration are established using the stress-strength interference theory. The random loads are applied several times and fuzzy structural strength is analyzed. The efficiency of the proposed method is demonstrated numerically through an example. The results have shown that the proposed method is practicable, feasible and gives a reasonably accurate prediction. The analysis shows that the probabilistic reliability is a special case of fuzzy reliability and fuzzy reliability of structural strength without degeneration is also a special case of fuzzy reliability with structural strength degeneration.

Continuous Conditional Random Field에 의한 인터넷 쇼핑몰 신규 고객등급 예측 (Prediction of New Customer's Degree of Loyalty of Internet Shopping Mall Using Continuous Conditional Random Field)

  • 안길승;허선
    • 대한산업공학회지
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    • 제41권1호
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    • pp.10-16
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    • 2015
  • In this study, we suggest a method to predict probability distribution of a new customer's degree of loyalty using C-CRF that reflects the RFM score and similarity to the neighbors of the customer. An RFM score prediction model is introduced to construct the first feature function of C-CRF. Integrating demographical similarity, purchasing characteristic similarity and purchase history similarity, we make a unified similarity variable to configure the second feature function of C-CRF. Then parameters of each feature function are estimated and we train our C-CRF model by training data set and suggest a probabilistic distribution to estimate a new customer's degree of loyalty. An example is provided to illustrate our model.

한반도에 대한 태풍내습확률 산정에 관한 연구 (A Study on the Probabilistic Prediction of Typhoons Approaching the Korean-Peninsula)

  • 박준일;유희정;이배호
    • 물과 미래
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    • 제17권4호
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    • pp.273-279
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    • 1984
  • An attempt is made to present a method of prediction for typhoons apporaching the Korean-peninsula. The method is based upon the Bayesian theorem to improve the observed (prior) probabilities of typhoons approaching the Korean sea area incorporating conditional probability. A total of 248 typhoons is collected and analyzed to establish prior probability and conditional probability according to the defined procedure. The typhoons used are those which encompassed the western Pacific area to which the Korean-peninsula is subjected. The results of examplary computations suggest that the presented method is promising for predicting approaching typhoons.

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합리적 교량유지관리 의사결정을 위한 구조성능의 추계학적 예측 (Probabilistic Prediction of Structural Performance for Rational Bridge Management Policy)

  • 오병환;김동욱
    • 한국구조물진단유지관리공학회 논문집
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    • 제8권4호
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    • pp.185-193
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    • 2004
  • 현재의 교량의 유지관리 시에 적절한 보수 시기나 최적화된 유지관리 정책을 결정하기 위하여 교량의 성능저하를 정확히 예측하는 것은 가장 중요한 일이다 이률 위해 제안된 방법은 정량적 평가, 마르코프체인, 베이시안 추정법 등으로 구성되었다. 제안된 방법에 따라 국내의 콘크리트 슬래브 교량을 예로서 예측을 하여는데, 기존의 전문가 의견조사 빛 외관조사에 의한 예측보다 좀 더 합리적인 결과를 보여주었다.

레이더와 비전센서 융합을 통한 전방 차량 인식 알고리즘 개발 (Radar and Vision Sensor Fusion for Primary Vehicle Detection)

  • 양승한;송봉섭;엄재용
    • 제어로봇시스템학회논문지
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    • 제16권7호
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    • pp.639-645
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    • 2010
  • This paper presents the sensor fusion algorithm that recognizes a primary vehicle by fusing radar and monocular vision data. In general, most of commercial radars may lose tracking of the primary vehicle, i.e., the closest preceding vehicle in the same lane, when it stops or goes with other preceding vehicles in the adjacent lane with similar velocity and range. In order to improve the performance degradation of radar, vehicle detection information from vision sensor and path prediction predicted by ego vehicle sensors will be combined for target classification. Then, the target classification will work with probabilistic association filters to track a primary vehicle. Finally the performance of the proposed sensor fusion algorithm is validated using field test data on highway.

프리스트레스트 콘크리트 교량의 크리프와 건조수축효과의 민감도 해석 (Sensitivity Analysis of Creep and Shrinkage Effects of Prestressed Concrete Bridges)

  • 오병환;양인환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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    • pp.656-661
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    • 1998
  • This paper presents a method of statistical analysis and sensitivity analysis of creep and shrinkage effects in PSC box girder bridges. The statistical and sensitivity analyses are performed by using the numerical simulation of Latin Hypercube sampling. For each sample, the time-dependent structural analysis is performed to produce response data, which are then statistically analyzed. The probabilistic prediction of the confidence limits on long-term effects of creep and shrinkage is then expressed. Three measures are examined to quantify the sensitivity of the outputs to each of the input variables. These are rank correlation coefficient(RCC), partial rank correlation coefficient(PRCC) and standardized rank regression coefficient(SRRC) computed on the ranks of the observations. Probability band widens with time, which indicates an increase of prediction uncertainty with time. The creep model uncertainty factor and the relative humidity appear as the most dominant factors with regard to the model output uncertainty.

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Discriminative Training of Sequence Taggers via Local Feature Matching

  • Kim, Minyoung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제14권3호
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    • pp.209-215
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    • 2014
  • Sequence tagging is the task of predicting frame-wise labels for a given input sequence and has important applications to diverse domains. Conventional methods such as maximum likelihood (ML) learning matches global features in empirical and model distributions, rather than local features, which directly translates into frame-wise prediction errors. Recent probabilistic sequence models such as conditional random fields (CRFs) have achieved great success in a variety of situations. In this paper, we introduce a novel discriminative CRF learning algorithm to minimize local feature mismatches. Unlike overall data fitting originating from global feature matching in ML learning, our approach reduces the total error over all frames in a sequence. We also provide an efficient gradient-based learning method via gradient forward-backward recursion, which requires the same computational complexity as ML learning. For several real-world sequence tagging problems, we empirically demonstrate that the proposed learning algorithm achieves significantly more accurate prediction performance than standard estimators.

네트워크 기반 시간지연 시스템을 위한 리세트 제어 및 확률론적 예측기법을 이용한 온라인 학습제어시스템 (Online Learning Control for Network-induced Time Delay Systems using Reset Control and Probabilistic Prediction Method)

  • 조현철;심광열;이권순
    • 제어로봇시스템학회논문지
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    • 제15권9호
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    • pp.929-938
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    • 2009
  • This paper presents a novel control methodology for communication network based nonlinear systems with time delay nature. We construct a nominal nonlinear control law for representing a linear model and a reset control system which is aimed for corrective control strategy to compensate system error due to uncertain time delay through wireless communication network. Next, online neural control approach is proposed for overcoming nonstationary statistical nature in the network topology. Additionally, DBN (Dynamic Bayesian Network) technique is accomplished for modeling of its dynamics in terms of casuality, which is then utilized for estimating prediction of system output. We evaluate superiority and reliability of the proposed control approach through numerical simulation example in which a nonlinear inverted pendulum model is employed as a networked control system.