• Title/Summary/Keyword: probabilistic

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SOME COMMON FIXED POINT THEOREMS WITH CONVERSE COMMUTING MAPPINGS IN BICOMPLEX-VALUED PROBABILISTIC METRIC SPACE

  • Sarmila Bhattacharyya;Tanmay Biswas;Chinmay Biswas
    • The Pure and Applied Mathematics
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    • v.31 no.3
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    • pp.299-310
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    • 2024
  • The probabilistic metric space as one of the important generalizations of metric space, was introduced by Menger [16] in 1942. Later, Choi et al. [6] initiated the notion of bicomplex-valued metric spaces (bi-CVMS). Recently, Bhattacharyya et al. [3] linked the concept of bicomplex-valued metric spaces and menger spaces, and initiated menger space with bicomplex-valued metric. Here, in this paper, we have taken probabilistic metric space with bicomplex-valued metric, i.e., bicomplexvalued probabilistic metric space and proved some common fixed point theorems using converse commuting mappings in this space.

An Evaluation of Probabilistic Strain-Life Curve in Polyacetal (폴리아세탈 소재의 확률론적 변형률-수명선도 평가)

  • Jang, Cheon-Soo;Kim, Chul-Su;Park, Bum-Gyu;Kim, Jung-Kyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.11 s.254
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    • pp.1417-1424
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    • 2006
  • In order to evaluate variation of fatigue life of mechanical components including engineering plastics, it is important to estimate probabilistic strain-life curves to accurately define the variation of fatigue characteristics. This paper intends to provide new assessment of P-$\varepsilon$-N (probabilistic strain-life curves) for considering the variation of fatigue characteristics in polyacetal. The fatigue strain controlled tests were conducted under constant 50% humidity and room temperature condition by a universal testing machine at strain ratio, R=0. A practical procedure is introduced to evaluate probabilistic strain-life curves. Three probabilistic distributions were used for generating P-$\varepsilon$-N curves such as normal, 2-parameter and 3-parameter Weibull. In this study, 3-parameter Weibull distribution was found to be most appropriate among assumed distributions when the probability distributions of the fatigue characteristic were examined using chi-square and Kolmogorov-Smirnov test. The more appropriate P-$\varepsilon$-N curves for these materials are generated by the proposed method considering 3-parameter Weibull distribution.

Distance Based Dynamic Probabilistic Broadcasting in Ad Hoc Wireless Networks

  • Kim Jae-Soo;Kim Jeong-Hong
    • Journal of Korea Multimedia Society
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    • v.8 no.12
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    • pp.1613-1622
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    • 2005
  • Broadcasting is fundamental and effective data dissemination mechanism for route discovery, address resolution, and many other network services in mobile ad hoc networks. Although many approaches for broadcasting have been proposed to minimize the number of retransmissions, none of them guarantee the best-suited bounds of retransmissions. Appropriate use of probabilistic method can lower the chance of contention and collision among neighboring nodes, so that it reduces the number of rebroadcasts. In this paper, we propose a probabilistic approach that dynamically adjusts the rebroadcasting probability according to the distance between the sender and the receiver. While the rebroadcast probabilities of a mobile node close to sender will be set lower, the rebroadcast probabilities of a mobile node far away from sender wi1l be set to higher, The rebroadcast probability of a node wi1l be set according to the distance from sender. We evaluate the performance of proposed approach by comparing it with flooding as well as a fixed probabilistic broadcast approach. Simulation results showed that the performance of proposed scheme outperforms by about $70\%$ than flooding scheme and outperforms by about $20\%$ than fixed probabilistic scheme.

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A study on Application of Probabilistic Fatigue Life Prediction for Aircraft Structures using the PoF based on Bayesian Approach (베이지안 기반의 파손확률을 이용한 항공기 구조물 확률론적 피로수명 예측 응용에 관한 연구)

  • Kim, Keun Won;Shin, Dae Han;Choi, Joo-Ho;Shin, Ki-Su
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.5
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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.

Syllable-based Probabilistic Models for Korean Morphological Analysis (한국어 형태소 분석을 위한 음절 단위 확률 모델)

  • Shim, Kwangseob
    • Journal of KIISE
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    • v.41 no.9
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    • pp.642-651
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    • 2014
  • This paper proposes three probabilistic models for syllable-based Korean morphological analysis, and presents the performance of proposed probabilistic models. Probabilities for the models are acquired from POS-tagged corpus. The result of 10-fold cross-validation experiments shows that 98.3% answer inclusion rate is achieved when trained with Sejong POS-tagged corpus of 10 million eojeols. In our models, POS tags are assigned to each syllable before spelling recovery and morpheme generation, which enables more efficient morphological analysis than the previous probabilistic models where spelling recovery is performed at the first stage. This efficiency gains the speed-up of morphological analysis. Experiments show that morphological analysis is performed at the rate of 147K eojeols per second, which is almost 174 times faster than the previous probabilistic models for Korean morphology.

Modified Probabilistic Neural Network of Heterogeneous Probabilistic Density Functions for the Estimation of Concrete Strength

  • Kim, Doo-Kie;Kim, Hee-Joong;Chang, Sang-Kil;Chang, Seong-Kyu
    • International Journal of Concrete Structures and Materials
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    • v.19 no.1E
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    • pp.11-16
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    • 2007
  • Recently, probabilistic neural network (PNN) has been proposed to predict the compressive strength of concrete for the known effect of improvement on PNN by the iteration method. However, an empirical method has been incorporated in the PNN technique to specify its smoothing parameter, which causes significant uncertainty in predicting the compressive strength of concrete. In this study, a modified probabilistic neural network (MPNN) approach is hence proposed. The global probability density function (PDF) of variables is reflected by summing the heterogeneous local PDFs which are automatically determined by the individual standard deviation of each variable. The proposed MPNN is applied to predict the compressive strength of concrete using actual test data from a concrete company. The estimated results of MPNN are compared with those of the conventional PNN. MPNN showed better results than the conventional PNN in predicting the compressive strength of concrete and provided promising results for the probabilistic approach to predict the concrete strength by using the individual standard deviation of a variable.

Probabilistic Damage Mechanics Assessment of Wall-Thinned Nuclear Piping Using Reliability Method and Monte-Carlo Simulation (신뢰도지수 및 몬데카를로 시뮬레이션을 이용한 원전 감육배관의 확률론적 손상역학 평가)

  • Lee Sang-Min;Yun Kang-Ok;Chang Yoon-Suk;Choi Jae-Boong;Kim Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.29 no.8 s.239
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    • pp.1102-1108
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    • 2005
  • The integrity of nuclear piping systems has to be maintained sufficiently all the times during operation. In order to maintain the integrity, reliable assessment procedures including fracture mechanics analysis, etc, are required. Up to now, the integrity assessment has been performed using conventional deterministic approach even though there are lots of uncertainties to hinder a rational evaluation. In this respect, probabilistic approach is considered as an appropriate method for piping system evaluation. The objectives of this paper are to develop a probabilistic assessment program using reliability index and simulation technique and to estimate the damage probability of wall-thinned pipes in secondary systems. The probabilistic assessment program consists of three evaluation modules which are first order reliability method, second order reliability method and Monte Carlo simulation method. The developed program has been applied to evaluate damage probabilities of wall-thinned pipes subjected to internal pressure, global bending moment and combined loading. The sensitivity analysis results as well as prototypal evaluation results showed a promising applicability of the probabilistic integrity assessment program.

The Analysis of the Seepage Quantity of Reservoir Embankment using Stochastic Response Surface Method (확률론적 응답면 기법을 이용한 저수지 제체의 침투수량 해석)

  • Bong, Tae-Ho;Son, Young-Hwan;Noh, Soo-Kack;Choi, Woo-Seok
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.3
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    • pp.75-84
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    • 2013
  • The seepage quantity analysis of reservoir embankment is very important for assessment of embankment safety. However, the conventional analysis does not consider uncertainty of soil properties. Permeability is known that the coefficient of variation is larger than other soil properties and seepage quantity is highly dependent on the permeability of embankment. Therefore, probabilistic analysis should be carried out for seepage analysis. To designers, however, the probabilistic analysis is not an easy task. In this paper, the method that can be performed probabilistic analysis easily and efficiently through the numerical analysis based commercial program is proposed. Stochastic response surface method is used for approximate the limit state function and when estimating the coefficients, the moving least squares method is applied in order to reduce local error. The probabilistic analysis is performed by LHC-MCS through the response surface. This method was applied to two type (homogeneous, core zone) earth dams and permeability of embankment body and core are considered as random variables. As a result, seepage quantity was predicted effectively by response surface and probabilistic analysis could be successfully implemented.

Probabilistic analysis for face stability of tunnels in Hoek-Brown media

  • Li, T.Z.;Yang, X.L.
    • Geomechanics and Engineering
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    • v.18 no.6
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    • pp.595-603
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    • 2019
  • A modified model combining Kriging and Monte Carlo method (MC) is proposed for probabilistic estimation of tunnel face stability in this paper. In the model, a novel uniform design is adopted to train the Kriging, instead of the existing active learning function. It has advantage of avoiding addition of new training points iteratively, and greatly saves the computational time in model training. The kinematic approach of limit analysis is employed to define the deterministic computational model of face failure, in which the Hoek-Brown failure criterion is introduced to account for the nonlinear behaviors of rock mass. The trained Kriging is used as a surrogate model to perform MC with dramatic reduction of calls to actual limit state function. The parameters in Hoek-Brown failure criterion are considered as random variables in the analysis. The failure probability is estimated by direct MC to test the accuracy and efficiency of the proposed probabilistic model. The influences of uncertainty level, correlation relationship and distribution type of random variables are further discussed using the proposed approach. In summary, the probabilistic model is an accurate and economical alternative to perform probabilistic stability analysis of tunnel face excavated in spatially random Hoek- Brown media.

A Reliability Analysis Application and Comparative Study on Probabilistic Structure Design for an Automatic Salt Collector (자동채염기의 확률론적 구조설계 구현을 위한 신뢰성 해석 응용과 비교연구)

  • Song, Chang Yong
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.19 no.12
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    • pp.70-79
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    • 2020
  • This paper describes a comparative study of characteristics of probabilistic design using various reliability analysis methods in the structure design of an automatic salt collector. The thickness sizing variables of the main structural member were considered to be random variables, including the uncertainty of corrosion, which would be an inevitable hazard in the work environment of the automatic salt collector. Probabilistic performance functions were selected from the strength performances of the automatic salt collector structure. First-order reliability method, second-order reliability method, mean value reliability method, and adaptive importance sampling method were applied during the reliability analyses. The probabilistic design performances such as reliability probability and numerical costs based on the reliability analysis methods were compared to the Monte Carlo simulation results. The adaptive importance sampling method showed the most rational results for the probabilistic structure design of the automatic salt collector.