• Journal of Korea Water Resources Association
• /
• v.37 no.1
• /
• pp.13-19
• /
• 2004

This study shows the possible use of the Poisson process for the characterization of dry year return period and duration. For the analysis we used an annual precipitation data, which has been collected since 1911 in Seoul. The highest threshold for the application of the Poisson process was determined to be the mean-0.5standard deviation, and then the results from the Poisson process are compared with the observed. Especially, the Poisson process was found to reproduce the mean duration and return interval quite well and show the possibility of using the Poisson process for the drought analysis.

• Proceedings of the Korean Society for Information Management Conference
• /
• 1999.08a
• /
• pp.9-12
• /
• 1999

통계적 확률이론에 근거한 포아송 모형을 색인어 선정 기반으로 활용하고자 하는 2-포아송 함수와 3-포아송 함수 및 다중 포아송 함수에 대한 단계적 발전 과정을 살펴보았다. 아울러, 2-포아송이 한국어 문헌의 색인어 선정에 유용한지 알아보기 위해 한국어 말뭉치 데이터베이스 내 문헌 50개를 실험 대상으로 단어의 장서빈도와 문헌빈도를 이용하여 z값을 산출해 보았다.

• Journal of the Korean Data and Information Science Society
• /
• v.10 no.2
• /
• pp.319-327
• /
• 1999

Zero-Inflated Poisson distributions have been widely used for defect-free products in manufacturing processes. It is very interesting to check the shift after the unknown changepoint. If the detectives are caused by the two different types of factor, we should use bivariate zero-inflated model. In this paper, likelihood ratio tests were used to detect the shift of changes after the changepoint. Some inferences for the parameters in this model were made.

• Communications for Statistical Applications and Methods
• /
• v.4 no.3
• /
• pp.753-763
• /
• 1997

컴퓨터의 발전에 따른 MCMC를 비동질적 포아송 과정에 이용하였다. 베이지안 추론에서 조건부 분포를 가지고 사후분포를 결정하는데 있어서의 계산 문제를 고려하였다. 특히 분포가 이중지수, 곰페르츠, 랄리, 감마, 그리고 검벨인 일반 순서통계량 모형에 대하여 깁스 샘플링과 메트로폴리스 알고리즘을 활용한 베이지안 계산과 모형선택을 제시하였다.

• Journal of Korea Water Resources Association
• /
• v.37 no.10
• /
• pp.813-822
• /
• 2004

This study quantifies and compares the drought return and duration characteristics by applying the Poisson process as well as based on by analyzing the observed data directly. The drought spatial distributions derived for the Gyunggi province are also compared. The monthly rainfall data are used to construct the SPI as a drought index. Especially, this study focuses on the evaluation of the Poisson process model when applying it to various data lengths such as in the spatial analysis 'of drought. Summarizing the results are as follows. (1) The Poisson process is found to be effective for the quantification of drought, especially when the data length is short. When applying the Poisson process, two neighboring sites are found insensitive to the data length to show similar drought characteristics, so the overall drought pattern becomes smoother than that derived directly from the observed data. (2) When the data length is very different site by site, the spatial analysis of drought based on a model application seems better than that based on the direct data analysis. This study also found more obvious spatial pattern of drought occurrence and duration when applying the Poisson process.

• The KIPS Transactions:PartD
• /
• v.10D no.5
• /
• pp.805-812
• /
• 2003

This paper presents a stochastic model for the software failure phenomenon based on a nonhomogeneous Poisson process (NHPP) and performs Bayesian inference using prior information. The failure process is analyzed to develop a suitable mean value function for the NHPP; expressions are given for several performance measure. The parametric inferences of the model using Logarithmic Poisson model, Crow model and Rayleigh model is discussed. Bayesian computation and model selection using the sum of squared errors. The numerical results of this models are applied to real software failure data. Tools of parameter inference was used method of Gibbs sampling and Metropolis algorithm. The numerical example by T1 data (Musa) was illustrated.

• Proceedings of the KAIS Fall Conference
• /
• 2011.05a
• /
• pp.176-178
• /
• 2011

본 연구에서는 소프트웨어 제품을 개발하여 테스팅을 거친 후 사용자에게 인도하는 시기를 결정하는 방출문제에 대하여 연구되었다. 인도시기에 관한 모형은 무한 고장수에 의존하는 비동질적인 포아송 과정을 적용하였다. 이러한 포아송 과정은 소프트웨어의 결함을 제거하거나 수정 작업 중에도 새로운 결함이 발생될 가능성을 반영하는 모형이다. 강도함수는 로그-로지스틱 패턴을 이용하였다. 따라서 소프트웨어 요구 신뢰도를 만족시키고 소프트웨어 개발 및 유지 총비용을 최소화 시키는 방출시간이 최적 소프트웨어 방출 정책이 된다.

• Proceedings of the KAIS Fall Conference
• /
• 2011.05a
• /
• pp.179-181
• /
• 2011

본 연구에서는 소프트웨어 제품을 개발하여 테스팅을 거친 후 사용자에게 인도하는 시기를 결정하는 방출문제에 대하여 연구되었다. 인도시기에 관한 모형은 무한 고장수에 의존하는 비동질적인 포아송 과정을 적용하였다. 이러한 포아송 과정은 소프트웨어의 결함을 제거하거나 수정 작업 중에도 새로운 결함이 발생될 가능성을 반영하는 모형이다. 강도함수는 중첩 패턴을 이용하였다. 따라서 소프트웨어 요구 신뢰도를 만족시키고 소프트웨어 개발 및 유지 총비용을 최소화 시키는 방출시간이 최적 소프트웨어 방출 정책이 된다.

• Journal of the Korean Geotechnical Society
• /
• v.29 no.1
• /
• pp.149-159
• /
• 2013

This paper deals with behaviors of Poisson's ratio with water content through uniaxial compressive strength against 307 individual rock cores, which are classified into sedimentary, igneous and metamorphic rock. Poissons' ratio demonstrates independent behaviors and does not correlate with mechanical and physical parameter of rocks. The water content behavior of Poissson's ratio represents decrease, increase and random style. Rock samples with decreasing behavior demonstrate absolute preponderance above the 70% level. As Poisson' ratio shows independent behaviors, it should be considered based on experimental results of in-situ rock in the process of design, construction, and supervision.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.4
• /
• pp.617-623
• /
• 2018

In this paper, we propose a novel seamless video composition method based on shape matching and Poisson equation. Video composition method consists of video segmentation process and video blending process. In the video segmentation process, the user first sets a trimap for the first frame, and then performs a grab-cut algorithm. Next, considering that the performance of video segmentation may be reduced if the color, brightness and texture of the object and the background are similar, the object region segmented in the current frame is corrected through shape matching between the objects of the current frame and the previous frame. In the video blending process, the object of source video and the background of target video are blended seamlessly using Poisson equation, and the object is located according to the movement path set by the user. Simulation results show that the proposed method has better performance not only in the naturalness of the composite video but also in computational time.