• 제목/요약/키워드: poisson model

검색결과 942건 처리시간 0.025초

포아슨 비의 변화를 고려한 수정 ECM 모델 개발 및 아스팔트 콘크리트의 저온 특성 연구 (Development of Modified Effective Crack Model to Take into Account for variation of Poisson's ratio and Low-Temperature Properties of Asphalt Concrete)

  • 권승준;도영수;김광우
    • 한국도로학회논문집
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    • 제3권1호
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    • pp.185-197
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    • 2001
  • 본 연구는 온도에 따라 특성이 변하는 아스팔트 콘크리트의 파괴인성을 규명하기 위하여 기존의 유효균열 모델을 수정하는 연구를 다루고 있다. 본래의 ECM모델은 콘크리트와 같은 고체에 적용되도록 개발되어 재료의 포아슨 비를 고려하지 않는다. 하지만 아스팔트 콘크리트는 온도변화에 민감하여 온도에 따라 포아슨 비가 변화하므로 다양한 온도하에서 정확한 파괴 특성을 알기 위해서는 포아슨 비가 고려되어져야 한다. 3개의 개질아스팔트 결합재를 포함한 4가지 결합재를 사용하여 밀입도 아스팔트 혼합물을 제조하여 초기균열 보에 대한 3점 휨 시험을 $-5^{\circ}C$부터 $-35^{\circ}C$까지에서 수행하였다. 탄성계수, 휨강도 및 파괴인성을 시험을 통하여 구하였다. 시험결과 포아슨비가 고려되는 수정 ECM 공식을 사용하므로서 보다 정확한 값들을 얻을 수 있었다. 폴리머 개질 아스팔트 혼합물이 일반아스팔트 혼합물에 비하여 더 낮은 저온하에서 더 높은 강성과 파괴인성을 유지함을 알 수 있었다.

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식중독 발생 예측모형 (Models for forecasting food poisoning occurrences)

  • 여인권
    • Journal of the Korean Data and Information Science Society
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    • 제23권6호
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    • pp.1117-1125
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    • 2012
  • 식중독 발생에 대한 기존 연구에서는 기온과 습도와 같은 기후변수가 주된 설명변수로 취급되어 왔다. 이 논문에서는 주별 식중독 발생건수와 기후변수 간에 관계를 고찰하고 식중독 발생건수를 예측하기 위한 모형으로 포아송 회귀모형과 자기회귀이동평균모형을 비교한다. 비교결과 우리나라 식중독 발생은 시차를 두고 기후 변수에 영향을 많이 받고 있으나 식중독 발생 예측은 이들 변수보다 이전 시점의 식중독 발생 건수에 더 많이 영향을 받는 것으로 나타났으며 포아송 회귀모형은 예측의 관점에서 문제가 있음을 보였다.

스킨스쿠버 해양어촌관광의 경제적 가치 추정: 제주도를 대상으로 (Estimating the Economic Value of Skin Scuba Marine Tourism: Focused on Jeju Island)

  • 강석규
    • 수산경영론집
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    • 제47권1호
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    • pp.21-29
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    • 2016
  • The purpose of this study is to estimate the economic value of skin scuba marine tourism activity in Jeju Island. The economic value is estimated as consumer surplus using count data models including the truncated Poisson model and the truncated negative binominal distribution model. This study collects the effective 369 questionnaires from skin scuba marine tourists through three times in Jeju Island. The truncated Poisson model was statistically more suitable and valid than other models. The truncated Poisson model was applied to estimate consumer surplus as economic value from skin scuba in Jeju Island. A consumer surplus value per trip was estimated as about 4,081,633 won. The annual economic value from skin scuba marine tourism activity was estimated as 8,428,571 won in Jeju Island. Consequently, skin scuba marine tourism activity has a very large economic value in Jeju Island.

Bayesian analysis for the bivariate Poisson regression model: Applications to road safety countermeasures

  • Choe, Hyeong-Gu;Lim, Joon-Beom;Won, Yong-Ho;Lee, Soo-Beom;Kim, Seong-W.
    • Journal of the Korean Data and Information Science Society
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    • 제23권4호
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    • pp.851-858
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    • 2012
  • We consider a bivariate Poisson regression model to analyze discrete count data when two dependent variables are present. We estimate the regression coefficients as sociated with several safety countermeasures. We use Markov chain and Monte Carlo techniques to execute some computations. A simulation and real data analysis are performed to demonstrate model fitting performances of the proposed model.

Empirical Bayes Estimate for Mixed Model with Time Effect

  • Kim, Yong-Chul
    • Communications for Statistical Applications and Methods
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    • 제9권2호
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    • pp.515-520
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    • 2002
  • In general, we use the hierarchical Poisson-gamma model for the Poisson data in generalized linear model. Time effect will be emphasized for the analysis of the observed data to be collected annually for the time period. An extended model with time effect for estimating the effect is proposed. In particularly, we discuss the Quasi likelihood function which is used to numerical approximation for the likelihood function of the parameter.

Two model comparisons of software reliability analysis for Burr type XII distribution

  • An, Jeong-Hyang
    • Journal of the Korean Data and Information Science Society
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    • 제23권4호
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    • pp.815-823
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    • 2012
  • In this paper reliability growth model in which the operating time between successive failure is a continuous random variable is proposed. This model is for Burr type XII distribution with two parameters which is discussed in two versions: the order statistics and non-homogeneous Poisson process. The two software reliability measures are obtained. The performance for two versions of the suggested model is tested on real data set by U-plot and Y-plot using Kolmogorov distance.

병렬화된 고속 보아송 방정식의 예측모델에의 적용 (Application of a Fast Parallel Poisson Solver to Barotropic Prediction Model)

  • 송창근;이상덕
    • 한국정보처리학회논문지
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    • 제4권3호
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    • pp.720-730
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    • 1997
  • 본 연구에서는 격자점의 갯수나 경계 조건에 관계없이 포아송 방정식을 푸는 일반적인 프로그램을 개발하고, 수퍼 컴퓨터의 병렬 기능과 벡터 기능을 이용하여 이 프로그램 을 고속화시켰다.우리는 실제 현압에 사용되고 있는 바로토로픽 예측 모델을 이용하여 실제 태풍인 Elena의 궤도를 예측하여 보았고, 병렬화된 고속의 포아송 방정식을 사용하는 경우 상당한 시간이 절약됨을 알 수 있었다. 72시간 후의 허리케인의 궤도 예측을 시도하였다. 3000여개의 격자점 위에서 시간 간격을 16분으로 하여 실험하였는데 8개 벡터 프로세서를 갖고 있는 Aliant FX/8에서 30초만에 이루어 졌고, 3.7의 계산 효율 을 얻어냈다.

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Predicting football scores via Poisson regression model: applications to the National Football League

  • Saraiva, Erlandson F.;Suzuki, Adriano K.;Filho, Ciro A.O.;Louzada, Francisco
    • Communications for Statistical Applications and Methods
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    • 제23권4호
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    • pp.297-319
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    • 2016
  • Football match predictions are of great interest to fans and sports press. In the last few years it has been the focus of several studies. In this paper, we propose the Poisson regression model in order to football match outcomes. We applied the proposed methodology to two national competitions: the 2012-2013 English Premier League and the 2015 Brazilian Football League. The number of goals scored by each team in a match is assumed to follow Poisson distribution, whose average reflects the strength of the attack, defense and the home team advantage. Inferences about all unknown quantities involved are made using a Bayesian approach. We calculate the probabilities of win, draw and loss for each match using a simulation procedure. Besides, also using simulation, the probability of a team qualifying for continental tournaments, being crowned champion or relegated to the second division is obtained.

Generalized half-logistic Poisson distributions

  • Muhammad, Mustapha
    • Communications for Statistical Applications and Methods
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    • 제24권4호
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    • pp.353-365
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    • 2017
  • In this article, we proposed a new three-parameter distribution called generalized half-logistic Poisson distribution with a failure rate function that can be increasing, decreasing or upside-down bathtub-shaped depending on its parameters. The new model extends the half-logistic Poisson distribution and has exponentiated half-logistic as its limiting distribution. A comprehensive mathematical and statistical treatment of the new distribution is provided. We provide an explicit expression for the $r^{th}$ moment, moment generating function, Shannon entropy and $R{\acute{e}}nyi$ entropy. The model parameter estimation was conducted via a maximum likelihood method; in addition, the existence and uniqueness of maximum likelihood estimations are analyzed under potential conditions. Finally, an application of the new distribution to a real dataset shows the flexibility and potentiality of the proposed distribution.

국내 회전교차로의 추돌사고 모형 개발 (Developing Rear-End Collision Models of Roundabouts in Korea)

  • 박병호;백태헌
    • 한국안전학회지
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    • 제29권6호
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    • pp.151-157
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    • 2014
  • This study deals with the rear-end collision at roundabouts. The purpose of this study is to develop the accident models of rear-end collision in Korea. In pursuing the above, this study gives particular attention to developing the appropriate models using Poisson, negative binomial model, ZAM, multiple linear and nonlinear regression models, and statistical analysis tools. The main results are as follows. First, the Vuong statistics and overdispersion parameters indicate that ZIP is the most appropriate model among count data models. Second, RMSE, MPB, MAD and correlation coefficient tests show that the multiple nonlinear model is the most suitable to the rear-end collision data. Finally, such the independent variables as traffic volume, ratio of heavy vehicle, number of circulatory roadway lane, number of crosswalk and stop line are adopted in the optimal model.