• Title/Summary/Keyword: Probabilistic Method.

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Analysis for Effect of Diffusion Parameter with Time-dependent Diffusion Coefficient on Service Life Considering Deterministic and Probabilistic Method (시간의존성 염화물 확산계수를 고려한 확산 영향인자가 결정론적 및 확률론적 내구수명에 미치는 영향분석)

  • Kwon, Seung-Jun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.4 no.3
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    • pp.259-268
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    • 2016
  • The service life evaluation in RC(Reinforced Concrete) structure exposed to chloride attack can be classified into deterministic and probabilistic method, and it significantly varies with design parameters. The present work derives PDF (Probability of Durability Failure) and the related service life considering time-dependent diffusion coefficient and internal parameters such as reference diffusion coefficient, critical chloride content, and time-exponent. When critical chloride content increases to 133.3%, the changing ratios of service life are 134.0~145.4% for deterministic method and 149.2%~152.5% for probabilistic method, respectively. In the case of increasing time-exponent to 200%, they increase to 323.8% for deterministic method and 346.0% for probabilistic method. Through adopting time-diffusion coefficient for probabilistic method, reasonable service life evaluation can be achieved, and it is also verified that increasing time-exponent through mineral admixture is very effective to extension of service life in RC structure.

New stereo matching algorithm based on probabilistic diffusion (확률적 확산을 이용한 스테레오 정합 알고리듬)

  • 이상화;이충웅
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.35S no.4
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    • pp.105-117
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    • 1998
  • In this paper, the general formula of disparity estimation based on Bayesian Maximum A Posteriori (MAP) algorithm is derived and implemented with simplified probabilistic models. The probabilistic models are independence and similarity among the neighboring disparities in the configuration.The formula is the generalized probabilistic diffusion equation based on Bayesian model, and can be implemented into the some different forms corresponding to the probabilistic models in the disparity neighborhood system or configuration. And, we proposed new probabilistic models in order to simplify the joint probability distribution of disparities in the configuration. According to the experimental results, the proposed algorithm outperformed the other ones, such as sum of swuared difference(SSD) based algorithm and Scharstein's method. We canconclude that the derived formular generalizes the probabilistic diffusion based on Bayesian MAP algorithm for disparity estimation, and the propsoed probabilistic models are reasonable and approximate the pure joint probability distribution very well with decreasing the computations to 0.01% of the generalized formula.

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Probabilistic Analysis of Vertical Drains using Hasofer-Lind Reliability Index (신뢰성지수를 이용한 연직배수공법의 확률론적 해석)

  • Kim, Seong-Pil;Heo, Joon;Bong, Tae-Ho
    • Journal of The Korean Society of Agricultural Engineers
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    • v.53 no.6
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    • pp.1-6
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    • 2011
  • The conventional factor of safety as used in geotechnical engineering does not reflect the degree of uncertainty of the relevant parameters. Then in the geotechnical engineering, there have been efforts to reflect the uncertainties of the geotechnical properties through probabilistic analysis. In this study, a practical method for probabilistic analysis using the Hasofer-Lind reliability index is introduced. The method is based on the perspective of an ellipsoid that just touches the failure surface in the original space of the variables. The method is applied to prefabricated vertical drains (PVD) and compared with the result of Monte Carlo Simulation method.

Evaluation of Spatial Consolidation Settlement by Probabilistic Method (확률론적 방법을 이용한 공간적 압밀침하량 평가)

  • Kim, Dong-Hee;Choi, Young-Min;Ko, Seong-Kwon;Lee, Woo-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.475-479
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    • 2010
  • For a rational evaluation of the spatial distribution of consolidation settlement, it is necessary to adopt probabilistic method. In this study, mean and standard deviation of consolidation settlement of whole analysis region are evaluated by using the spatial distribution of consolidation layer which is estimated from kriging and statistics of soil properties. Using these results and probabilistic method, the area need to be raised the ground level for balancing the final design ground level are determined.

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Localization of a Monocular Camera using a Feature-based Probabilistic Map (특징점 기반 확률 맵을 이용한 단일 카메라의 위치 추정방법)

  • Kim, Hyungjin;Lee, Donghwa;Oh, Taekjun;Myung, Hyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.4
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    • pp.367-371
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    • 2015
  • In this paper, a novel localization method for a monocular camera is proposed by using a feature-based probabilistic map. The localization of a camera is generally estimated from 3D-to-2D correspondences between a 3D map and an image plane through the PnP algorithm. In the computer vision communities, an accurate 3D map is generated by optimization using a large number of image dataset for camera pose estimation. In robotics communities, a camera pose is estimated by probabilistic approaches with lack of feature. Thus, it needs an extra system because the camera system cannot estimate a full state of the robot pose. Therefore, we propose an accurate localization method for a monocular camera using a probabilistic approach in the case of an insufficient image dataset without any extra system. In our system, features from a probabilistic map are projected into an image plane using linear approximation. By minimizing Mahalanobis distance between the projected features from the probabilistic map and extracted features from a query image, the accurate pose of the monocular camera is estimated from an initial pose obtained by the PnP algorithm. The proposed algorithm is demonstrated through simulations in a 3D space.

Estimation Model for Optimum Probabilistic Rainfall Intensity on Hydrological Area - With Special Reference to Chonnam, Buk and Kyoungnam, Buk Area - (수문지역별 최적확률강우강도추정모형의 재정립 -영.호남 지역을 중심으로 -)

  • 엄병헌;박종화;한국헌
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.38 no.2
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    • pp.108-122
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    • 1996
  • This study was to introduced estimation model for optimum probabilistic rainfall intensity on hydrological area. Originally, probabilistic rainfall intensity formula have been characterized different coefficient of formula and model following watersheds. But recently in korea rainfall intensity formula does not use unionize applyment standard between administration and district. And mingle use planning formula with not assumption model. Following the number of year hydrological duration adjust areal index. But, with adjusting formula applyment was without systematic conduct. This study perceive the point as following : 1) Use method of excess probability of Iwai to calculate survey rainfall intensity value. 2) And, use method of least squares to calculate areal coefficient for a unit of 157 rain gauge station. And, use areal coefficient was introduced new probabilistic rainfall intensity formula for each rain gauge station. 3) And, use new probabilistic rainfall intensity formula to adjust a unit of fourteen duration-a unit of fifteen year probabilistic rainfall intensity. 4) The above survey value compared with adjustment value. And use three theory of error(absolute mean error, squares mean error, relative error ratio) to choice optimum probabilistic rainfall intensity formula for a unit of 157 rain gauge station.

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Determining Direction of Conditional Probabilistic Dependencies between Clusters (클러스터간 조건부 확률적 의존의 방향성 결정에 대한 연구)

  • Jung, Sung-Won;Lee, Do-Heon;Lee, Kwang-H.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.17 no.5
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    • pp.684-690
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    • 2007
  • We describe our method to predict the direction of conditional probabilistic dependencies between clusters of random variables. Selected variables called 'gateway variables' are used to predict the conditional probabilistic dependency relations between clusters. The direction of conditional probabilistic dependencies between clusters are predicted by finding directed acyclic graph (DAG)-shaped dependency structure between the gateway variables. We show that our method shows meaningful prediction results in determining directions of conditional probabilistic dependencies between clusters.

Improvement of Mid/Long-Term ESP Scheme Using Probabilistic Weather Forecasting (확률기상예보를 이용한 중장기 ESP기법 개선)

  • Kim, Joo-Cheol;Kim, Jeong-Kon;Lee, Sang-Jin
    • Journal of Korea Water Resources Association
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    • v.44 no.10
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    • pp.843-851
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    • 2011
  • In hydrology, it is appropriate to use probabilistic method for forecasting mid/long term streamflow due to the uncertainty of input data. Through this study, it is expanded mid/long term forecasting system more effectively adding priory process function based on PDF-ratio method to the RRFS-ESP system for Guem River Basin. For implementing this purpose, weight is estimated using probabilistic weather forecasting information from KMA. Based on these results, ESP probability is updated per scenario. Through the estimated result per method, the average forecast score using ESP method is higher than that of naive forecasting and it confirmed that ESP method results in appropriate score for RRFS-ESP system. It is also shown that the score of ESP method applying revised inflow scenario using probabilistic weather forecasting is higher than that of ESP method. As a results, it will be improved the accuracy of forecasting using probabilistic weather forecasting.

Parametric study on probabilistic local seismic demand of IBBC connection using finite element reliability method

  • Taherinasab, Mohammad;Aghakouchak, Ali A.
    • Steel and Composite Structures
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    • v.37 no.2
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    • pp.151-173
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    • 2020
  • This paper aims to probabilistically evaluate performance of two types of I beam to box column (IBBC) connection. With the objective of considering the variability of seismic loading demand, statistical features of the inter-story drift ratio corresponding to the second, fifth and eleventh story of a 12-story steel special moment resisting frames are extracted through incremental dynamic analysis at global collapse state. Variability of geometrical variables and material strength are also taken into account. All of these random variables are exported as inputs to a probabilistic finite element model which simulates the connection. At the end, cumulative distribution functions of local seismic demand for each component of each connection are provided using histogram sampling. Through a parametric study on probabilistic local seismic demand, the influence of some geometrical random variables on the performance of IBBC connections is demonstrated. Furthermore, the probabilistic study revealed that IBBC connection with widened flange has a better performance than the un-widened flange. Also, a design procedure is proposed for WF connections to achieve a same connection performance in different stories.

A Probabilistic Approach to Small Signal Stability Analysis of Power Systems with Correlated Wind Sources

  • Yue, Hao;Li, Gengyin;Zhou, Ming
    • Journal of Electrical Engineering and Technology
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    • v.8 no.6
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    • pp.1605-1614
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    • 2013
  • This paper presents a probabilistic methodology for small signal stability analysis of power system with correlated wind sources. The approach considers not only the stochastic characteristics of wind speeds which are treated as random variables with Weibull distributions, while also the wind speed spatial correlations which are characterized by a correlation matrix. The approach based on the 2m+1 point estimate method and Cornish Fisher expansion, the orthogonal transformation technique is used to deal with the correlation of wind farms. A case study is carried out on IEEE New England system and the probabilistic indexes for eigenvalue analysis are computed from the statistical processing of the obtained results. The accuracy and efficiency of the proposed method are confirmed by comparing with the results of Monte Carlo simulation. The numerical results indicate that the proposed method can actually capture the probabilistic characteristics of mode properties of the power systems with correlated wind sources and the consideration of spatial correlation has influence on the probability of system small signal stability.