• Title/Summary/Keyword: Poisson Distribution

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Measurement of the Photocount Distribution of the Quasi-thermal Light Source (준열광원에서 방출되는 빛의 광전자 분포 측정)

  • Kim, Heon-Oh;Ha, Yang;Shin, Jong-Tae;Park, Goo-Dong;Kim, Tae-Soo
    • Korean Journal of Optics and Photonics
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    • v.9 no.3
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    • pp.129-133
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    • 1998
  • The phtocount distributions of a quasi-thermal light source were measured by using the photoelectric counting method. The source was fabricated from the ground glass plate of 9${\mu}{\textrm}{m}$ roughness illuminated by linearly polarized He-Ne laser beam. The coherence time of the quasi-thermal light changed from 31.4$mutextrm{s}$ to 2.48$mutextrm{s}$ according to the grain velocity of the ground glass plate. The photocount distribution showed the Bose-Einstein statistics for a long coherence time compared to the counting time interval, while the distribution approaches the Poisson distribution when the coherence time much shorter than the counting time.

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(Continuous-Time Queuing Model and Approximation Algorithm of a Packet Switch under Heterogeneous Bursty Traffic) (이질적 버스트 입력 트래픽 환경에서 패킷 교환기의 연속 시간 큐잉 모델과 근사 계산 알고리즘)

  • 홍석원
    • Journal of KIISE:Information Networking
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    • v.30 no.3
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    • pp.416-423
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    • 2003
  • This paper proposes a continuous-time queuing model of a shared-buffer packet switch and an approximate algorithm. N arrival processes have heterogeneous busty traffic characteristics. The arrival processes are modeled by Coxian distribution with order 2 that is equivalent to Interruped Poisson Process. The service time is modeled by Erlang distribution with r stages. First the approximate algorithm performs the aggregation of N arrival processes as a single state variable. Next the algorithm discompose the queuing system into N subsystems which are represented by aggregated state variables. And the balance equations based on these aggregated state variables are solved for by iterative method. Finally the algorithm is validated by comparing the results with those of simulation.

Dependence of Drain Induced Barrier Lowering for Doping Profile of Channel in Double Gate MOSFET (이중게이트 MOSFET에서 채널내 도핑분포에 대한 드레인유기장벽감소 의존성)

  • Jung, Hak-Kee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.9
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    • pp.2000-2006
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    • 2011
  • In this paper, the drain induced barrier lowering(DIBL) for doping distribution in the channel has been analyzed for double gate MOSFET(DGMOSFET). The DGMOSFET is extensively been studing because of adventages to be able to reduce the short channel effects(SCEs) to occur in convensional MOSFET. DIBL is SCE known as reduction of threshold voltage due to variation of energy band by high drain voltage. This DIBL has been analyzed for structural parameter and variation of channel doping profile for DGMOSFET. For this object, The analytical model of Poisson equation has been derived from Gaussian doping distribution for DGMOSFET. To verify potential and DIBL models based on this analytical Poisson's equation, the results have been compared with those of the numerical Poisson's equation, and DIBL for DGMOSFET has been investigated using this models.

[ $P_{\lambda,;,T}^M-policy$ ] of a finite dam with both continuous and Jumpwise inputs

  • Lim Kyung Eun;Baek Jee Seon;Lee Eui Yong
    • Proceedings of the Korean Statistical Society Conference
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    • 2004.11a
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    • pp.123-128
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    • 2004
  • A finite dam under $P_{\lambda,;,T}^M-policy$ is considered, where the input of water is formed by a Wiener process subject to random jumps arriving according to a Poisson process. Explicit expression is deduced for the stationary distribution of the level of water. And the long-run average cost per unit time is obtained after assigning costs to the changes of release rate, a reward to each unit of output, and a penalty which is a function of the level of water in the reservoir.

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Bayesian Methods for Generalized Linear Models

  • Paul E. Green;Kim, Dae-Hak
    • Communications for Statistical Applications and Methods
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    • v.6 no.2
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    • pp.523-532
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    • 1999
  • Generalized linear models have various applications for data arising from many kinds of statistical studies. Although the response variable is generally assumed to be generated from a wide class of probability distributions we focus on count data that are most often analyzed using binomial models for proportions or poisson models for rates. The methods and results presented here also apply to many other categorical data models in general due to the relationship between multinomial and poisson sampling. The novelty of the approach suggested here is that all conditional distribution s can be specified directly so that staraightforward Gibbs sampling is possible. The prior distribution consists of two stages. We rely on a normal nonconjugate prior at the first stage and a vague prior for hyperparameters at the second stage. The methods are demonstrated with an illustrative example using data collected by Rosenkranz and raftery(1994) concerning the number of hospital admissions due to back pain in Washington state.

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Regression models generated by gamma random variables with long-term survivors

  • Ortega, Edwin M.M.;Cordeiro, Gauss M.;Hashimoto, Elizabeth M.;Suzuki, Adriano K.
    • Communications for Statistical Applications and Methods
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    • v.24 no.1
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    • pp.43-65
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    • 2017
  • We propose a flexible cure rate survival model by assuming that the number of competing causes of the event of interest has the Poisson distribution and the time for the event follows the gamma-G family of distributions. The extended family of gamma-G failure-time models with long-term survivors is flexible enough to include many commonly used failure-time distributions as special cases. We consider a frequentist analysis for parameter estimation and derive appropriate matrices to assess local influence on the parameters. Further, various simulations are performed for different parameter settings, sample sizes and censoring percentages. We illustrate the performance of the proposed regression model by means of a data set from the medical area (gastric cancer).

Comparative Performance Analysis of Network Security Accelerator based on Queuing System

  • Yun Yeonsang;Lee Seonyoung;Han Seonkyoung;Kim Youngdae;You Younggap
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.269-273
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    • 2004
  • This paper presents a comparative performance analysis of a network accelerator model based on M/M/l queuing system. It assumes the Poisson distribution as its input traffic load. The decoding delay is employed as a performance analysis measure. Simulation results based on the proposed model show only $15\%$ differences with respect to actual measurements on field traffic for BCM5820 accelerator device. The performance analysis model provides with reasonable hardware structure of network servers, and can be used to span design spaces statistically.

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On the tensile strength of brittle materials with a consideration of Poisson's ratios

  • Hu Guoming;Cho Heechan;Wan Hui;Ohtaki Hideyuki
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.603-610
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    • 2003
  • The influence of Poisson's ratio on the tensile strength of brittle materials is neglected in many studies. When brittle materials are loaded in compression or impact, substantial tensile stresses are induced within the materials. These tensile stresses are responsible for splitting failure of the materials. In this paper, the state of stress in a spherical particle due to two diametrically opposed forces is analyzed theoretically. A simple equation for the state of stress at the center of the particle is obtained. An analysis of the distribution of stresses along the z-axis due to distributed pressures and concentrated forces, and on diametrically horizontal plane due to concentrated forces, shows that it is reasonable to propose the tensile stress at the center of the particle at the point of failure as a tensile strength of the particle. Moreover, the tensile strength is a function of the Poisson's ratio of the material. As the state of stress along the z-axis in an irregular specimen tends to be similar to that in a spherical particle compressed diametrically with the same force, this tensile strength has some validity for irregular particles as well. Therefore, it can be proposed as the tensile strength for brittle materials generally. The effect of Poisson's ratio on the tensile strength is discussed.

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Importance of the Temporal Variability of Rainfall Statistics in Stochastic Rainfall Modeling (추계강우모형에서의 강우통계의 시간적 변동성 연구)

  • Kim, Dong-Kyun;Lee, Jin-Woo;Cho, Yong-Sik
    • 한국방재학회:학술대회논문집
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    • 2010.02a
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    • pp.51.2-51.2
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    • 2010
  • A novel approach of Poisson cluster stochastic rainfall generator was validated in its ability to reproduce important rainfall and watershed response characteristics at 104 locations of the United States. The suggested novel approach - The Hybrid Model(THM), as compared to the traditional ones, has an additional function to account for the year-to-year variability of rainfall statistics. The two-sample Kolmogorov-Smirnov test was used to see how well THM and traditional approach of Poisson cluster rainfall model reproduce the distribution of the following hydrologic variables: monthly maximum rainfall depths with 1, 3, 6, 12, and 24 hour duration, monthly maximum flow peaks at the virtual watersheds with Curve Number of 50, 60, 70, 80 and 90; and monthly runoff depths at the same virtual watersheds. In all of the testing variables, THM significantly outperformed the traditional approach. This result indicates that the year-to-year variability of rainfall statistics contains important information about the characteristics of rainfall processes that were not considered by the conventional approach of Poisson cluster rainfall modeling and that further considering it in rainfall simulation will enhance the performance of the rainfall models.

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QUEUE LENGTH DISTRIBUTION IN A QUEUE WITH RELATIVE PRIORITIES

  • Kim, Jeong-Sim
    • Bulletin of the Korean Mathematical Society
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    • v.46 no.1
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    • pp.107-116
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    • 2009
  • We consider a single server multi-class queueing model with Poisson arrivals and relative priorities. For this queue, we derive a system of equations for the transform of the queue length distribution. Using this system of equations we find the moments of the queue length distribution as a solution of linear equations.