• Title/Summary/Keyword: sampling set

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Inference of Parameters for Superposition with Goel-Okumoto model and Weibull model Using Gibbs Sampler

  • Heecheul Kim
    • Communications for Statistical Applications and Methods
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    • v.6 no.1
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    • pp.169-180
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    • 1999
  • A Markov Chain Monte Carlo method with development of computation is used to be the software system reliability probability model. For Bayesian estimator considering computational problem and theoretical justification we studies relation Markov Chain with Gibbs sampling. Special case of GOS with Superposition for Goel-Okumoto and Weibull models using Gibbs sampling and Metropolis algorithm considered. In this paper discuss Bayesian computation and model selection using posterior predictive likelihood criterion. We consider in this paper data using method by Cox-Lewis. A numerical example with a simulated data set is given.

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A High Quality Mesh Generation for Surfaces in the Use of Interval Arithmetic

  • Kikuchi, Ryota;Makino, Mitsunori
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.1153-1156
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    • 2002
  • In this parer, a high quality mesh generation method by using interval arithmetic is proposed. In the proposed method, the variance of a tangent vector at the point is considered by the automatic differentiation. From the variance, sampling points on the surface are judged whether it is adequate or not, which is calculated by the interval arithmetic. Then Delaunay triangulation is performed to the obtained sampling points, and a set of meshes is generated. The proposed method is hard to overlook the local variation of surfaces.

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Semiparametric Bayesian Regression Model for Multiple Event Time Data

  • Kim, Yongdai
    • Journal of the Korean Statistical Society
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    • v.31 no.4
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    • pp.509-518
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    • 2002
  • This paper is concerned with semiparametric Bayesian analysis of the proportional intensity regression model of the Poisson process for multiple event time data. A nonparametric prior distribution is put on the baseline cumulative intensity function and a usual parametric prior distribution is given to the regression parameter. Also we allow heterogeneity among the intensity processes in different subjects by using unobserved random frailty components. Gibbs sampling approach with the Metropolis-Hastings algorithm is used to explore the posterior distributions. Finally, the results are applied to a real data set.

Bayesian Inference for Modified Jelinski-Moranda Model by using Gibbs Sampling (깁스 샘플링을 이용한 변형된 Jelinski-Moranda 모형에 대한 베이지안 추론)

  • 최기헌;주정애
    • Journal of Applied Reliability
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    • v.1 no.2
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    • pp.183-192
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    • 2001
  • Jelinski-Moranda model and modified Jelinski-Moranda model in software reliability are studied and we consider maximum likelihood estimator and Bayes estimates of the number of faults and the fault-detection rate per fault. A gibbs sampling approach is employed to compute the Bayes estimates, future survival function is examined. Model selection based on prequential likelihood of the conditional predictive ordinates. A numerical example with simulated data set is given.

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A Post-stratified Estimation in Multivariate Stratified Sampling Surveys

  • Park, Jinwoo
    • Communications for Statistical Applications and Methods
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    • v.6 no.3
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    • pp.755-760
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    • 1999
  • In multivariate stratified sampling surveys it is general to use a few stratification variables which are highly correlated with the important variables at design stage. But there might be some secondary study variables which are not so highly correlated with those stratification variables. In that case it is not efficient to use the same type of estimator due to the secondary variables as the one base on the important variables. A post-stratified estimation is proposed to increase the efficiency of the estimator with existence of secondary variables. The proposed method is illustrated with a set of fishery household population survey data.

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A Study of Sample Size for Two-Stage Cluster Sampling (이단계 집락추출에서의 표본크기에 대한 연구)

  • Song, Jong-Ho;Jea, Hea-Sung;Park, Min-Gue
    • The Korean Journal of Applied Statistics
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    • v.24 no.2
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    • pp.393-400
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    • 2011
  • In a large scale survey, cluster sampling design in which a set of observation units called clusters are selected is often used to satisfy practical restrictions on time and cost. Especially, a two stage cluster sampling design is preferred when a strong intra-class correlation exists among observation units. The sample Primary Sampling Unit(PSU) and Secondary Sampling Unit(SSU) size for a two stage cluster sample is determined by the survey cost and precision of the estimator calculated. For this study, we derive the optimal sample PSU and SSU size when the population SSU size across the PSU are di erent by extending the result obtained under the assumption that all PSU have the same number of SSU. The results on the sample size are then applied to the $4^{th}$ Korea Hospital Discharge results and is compared to the conventional method. We also propose the optimal sample SSU (discharged patients) size for the $7^{th}$ Korea Hospital Discharge Survey.

Development of an Evaluation Method for Flow Rate Performance of Particulate Sampling Pump using Three-pieces Cassette Holder Containing Filters (여과지가 장착된 3단 카세트를 이용한 입자상물질 채취용 펌프의 유량성능 평가방법)

  • Song, Ho-June;Kim, Nam-Hee;Kim, Ki-Youn;Ma, Hye-Lan;Lee, Kwang-Young;Jeong, Jee-Yeon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.23 no.4
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    • pp.348-355
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    • 2013
  • Objectives: In working environment measurement, sampling is an important stage for obtaining reliable result as analysis. A personal air sampling pump is one of the most fundamental and important element in the work environment measurement, but it remains at the level of calibrating the flow rate of the pump before and after sampling. There is no checking whether the flow rate set at the initial stage would be hold during sampling. The purpose of this study was to develop a method to evaluate the flow rate performance of particulate sampling pump with three-pieces cassette holder containing filters commonly used to sample particulate. Materials and methods: We tested back pressure of particulate sampling pumps commonly used in Korea with three-pieces cassette holder containing various filters, and tried to find out the combination conditions of filters in accordance with back pressure required by ISO standard 13137. Results: We found out the matrix of sampling media such as three-pieces cassette holder containing filters applicable to the pressure drop required by the ISO standard for evaluating the flow rate stability under increasing pressure drop and long term(8 hour) performance. Conclusions: This evaluation method using sampling media matrix for checking flow rate stability proposed by this study could be very useful tool to find out good performance pumps before sampling.

Time-Matching Poisson Multi-Bernoulli Mixture Filter For Multi-Target Tracking In Sensor Scanning Mode

  • Xingchen Lu;Dahai Jing;Defu Jiang;Ming Liu;Yiyue Gao;Chenyong Tian
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.6
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    • pp.1635-1656
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    • 2023
  • In Bayesian multi-target tracking, the Poisson multi-Bernoulli mixture (PMBM) filter is a state-of-the-art filter based on the methodology of random finite set which is a conjugate prior composed of Poisson point process (PPP) and multi-Bernoulli mixture (MBM). In order to improve the random finite set-based filter utilized in multi-target tracking of sensor scanning, this paper introduces the Poisson multi-Bernoulli mixture filter into time-matching Bayesian filtering framework and derive a tractable and principled method, namely: the time-matching Poisson multi-Bernoulli mixture (TM-PMBM) filter. We also provide the Gaussian mixture implementation of the TM-PMBM filter for linear-Gaussian dynamic and measurement models. Subsequently, we compare the performance of the TM-PMBM filter with other RFS filters based on time-matching method with different birth models under directional continuous scanning and out-of-order discontinuous scanning. The results of simulation demonstrate that the proposed filter not only can effectively reduce the influence of sampling time diversity, but also improve the estimated accuracy of target state along with cardinality.

Improved Association Rule Mining by Modified Trimming (트리밍 방식 수정을 통한 연관규칙 마이닝 개선)

  • Hwang, Won-Tae;Kim, Dong-Seung
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.3
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    • pp.15-21
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    • 2008
  • This paper presents a new association mining algorithm that uses two phase sampling for shortening the execution time at the cost of precision of the mining result. Previous FAST(Finding Association by Sampling Technique) algorithm has the weakness in that it only considered the frequent 1-itemsets in trimming/growing, thus, it did not have ways of considering mulit-itemsets including 2-itemsets. The new algorithm reflects the multi-itemsets in sampling transactions. It improves the mining results by adjusting the counts of both missing itemsets and false itemsets. Experimentally, on a representative synthetic database, the algorithm produces a sampled subset of results with an increased accuracy in terms of the 2-itemsets while it maintains the same 1uality of the data set.

Design of a 3-D Adaptive Sampling Rate Tracking Algorithm for a Phased Array Radar (위상배열 레이다를 위한 3차원 적응 표본화 빈도 추적 알고리듬의 설계)

  • Son, Keon;Hong, Sun-Mog
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.5
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    • pp.62-72
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    • 1993
  • The phased array antenna has the ability to perform adaptive sampling by directing the radar beam without inertia in any direction. The adaptive sampling capability of the phased array antenna allows each sampling time interval to be varied for each target, depending on the acceleration of each target at any time. In this paper we design a three dimensional adaptive target tracking algorithm for the phased array radar system with a given set of measurement parameters. The tracking algorithm avoids taking unnecessarily frequent samples, while keeping the angular prediction error within a fraction of antenna beamwidth so that the probability of detection will not be degraded during a track updata illuminations. In our algorithm, the target model and the sampling rate are selected depending on the target range and the target maneuver status which is determined by a maneuver level detector. A detailed simulation is conducted to test the validity of our tracking algorithm for target trajectories under various conditions of maneuver.

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