• 제목/요약/키워드: Size distributions

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MISCLASSIFICATION IN SIZE-BIASED MODIFIED POWER SERIES DISTRIBUTION AND ITS APPLICATIONS

  • Hassan, Anwar;Ahmad, Peer Bilal
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제13권1호
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    • pp.55-72
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    • 2009
  • A misclassified size-biased modified power series distribution (MSBMPSD) where some of the observations corresponding to x = c + 1 are misclassified as x = c with probability $\alpha$, is defined. We obtain its recurrence relations among the raw moments, the central moments and the factorial moments. Discussion of the effect of the misclassification on the variance is considered. To illustrate the situation under consideration some of its particular cases like the size-biased generalized negative binomial (SBGNB), the size-biased generalized Poisson (SBGP) and sizebiased Borel distributions are included. Finally, an example is presented for the size-biased generalized Poisson distribution to illustrate the results.

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2009-2010년 봄철 심한 황사 사례에 대한 에어러솔 크기 분포와 광학적 특성 (Aerosol Size Distributions and Optical Properties during Severe Asian Dust Episodes Measured over South Korea in Spring of 2009-2010)

  • 강동훈;김지영;김경익;임병숙
    • 대기
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    • 제22권3호
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    • pp.367-379
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    • 2012
  • Measurements of $PM_{10}$ mass concentration, aerosol light scattering and absorption coefficients as well as aerosol size distribution were made to characterize the aerosol physical and optical properties at the two Korean WMO/GAW regional stations, Anmyeondo and Gosan. Episodic cases of the severe Asian dust events occurred in spring of 2009-2010 were studied. Results in this study show that the aerosol size distributions and optical properties at both stations are closely associated with the dust source regions and the transport routes. According to the comparison of the $PM_{10}$ mass concentration at both stations, the aerosol concentrations at Anmyeondo are not always higher than those at Gosan although the distance from the dust source region to Anmyeondo is closer than that of Gosan. The result shows that the aerosol concentrations depend on the transport routes of the dust-containing airmass. The range of mass scattering efficiencies at Anmyeon and Gosan was 0.50~1.45 and $0.62{\sim}1.51m^2g^{-1}$, respectively. The mass scattering efficiencies are comparable to those of the previous studies by Clarke et al. (2004) and Lee (2009). It is noted that anthropogenic fine particles scatter more effectively the sunlight than coarse dust particles. Finally, we found that the aerosol size distribution and optical properties at Anmyeondo and Gosan show somewhat different properties although the samples for the same dust_episodic events are compared.

나무 아래 빗방울(雨滴)의 물리적 특성변화 분석 (Evaluation of Changesin the Physical Characteristics of Raindrops Under a Canopy in Central Korea)

  • 김진관;김민석;양동윤;임영신
    • 한국지형학회지
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    • 제23권3호
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    • pp.105-122
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    • 2016
  • To evaluate the changes in the physical characteristics of open rainfall related to canopy effects and rainfall intensity in Korea, the terminal velocity of raindrops and drop size distributions(DSD) were continuously measured by an optical-laser disdrometer in an open site(Op) and in two forest stands(Th1: Larix leptolepis, Th2: Pinus koraiensis) during five rainfall events in 2008. The terminal velocity, DSD and two forms of kinetic energy(KE, $Jm^{-2}$ $mm^{-1}$; KER, $Jm^{-2}$ $h^{-1}$) of open rainfall drops were determined and were compared with those of throughfall drops under two different canopy heights. The effects of the canopy and rainfall intensity, together with wind speed, on the changes in drop size and kinetic energy of throughfall were evaluated. Throughfall drops were larger than open rainfall drops. The distribution of terminal velocities for the drop sizes measured at Th2 was lower than that at Op; however, at Th1 the distribution was similar to that at Op. The total kinetic energy of throughfall at Th1 and Th2 was higher than the total kinetic energy of open rainfall, and the kinetic energy distribution for the drop sizes wassimilar to the drop size distribution. The observed throughfall-KER at Th1 was lower than an estimate previously produced using a model. The overestimation from the modeled value at Th1 was likely to be due to overestimated values of a square root transformation of fall height and its coefficient in the model because the distributions of terminal velocity for the drop size measured at Th1 were similar to those of open rainfall.

딥앙상블 물리 정보 신경망을 이용한 기포 크기 분포 추정 (Estimation of bubble size distribution using deep ensemble physics-informed neural network)

  • 고선영;김근환;이재혁;구홍주;문광호;추영민
    • 한국음향학회지
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    • 제42권4호
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    • pp.305-312
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    • 2023
  • 기포 크기 분포를 음파 감쇄 손실을 이용하여 역산하기 위해 Physics-Informed Neural Network(PINN)을 사용하였다. 역산에 사용되는 선형시스템을 풀기 위해 이미지 처리 분야에서 선형시스템 문제를 해결한 Adaptive Learned Iterative Shrinkage Thresholding Algorithm(Ada-LISTA)를 PINN의 신경망 구조로 이용하였다. 더 나아가, PINN의 손실함수에 선형시스템 기반의 정규항을 포함함으로써 PINN의 해가 기포 물리 법칙을 만족하여 더 높은 일반화 성능을 가지도록 하였다. 그리고 기포 추정값의 불확실성을 계산하기 위해 딥앙상블 기법을 이용하였다. 서로 다른 초기값을 갖는 20개의 Ada-LISTA는 같은 훈련데이터를 이용하여 학습되었다. 이 후 테스트시 훈련데이터와 다른 경향의 감쇄 손실을 입력으로 사용하여 기포 크기 분포를 추정하였고, 추정값과 이에 대한 불확실성을 20개 추정값의 평균과 분산으로 각각 구하였다. 그 결과 딥앙상블이 적용된 Ada-LISTA는 기존 볼록 최적화 기법인 CVX보다 기포 크기 분포를 역산하는데 더 우수한 성능을 보였다.

A note on the sample size determination of sequential and multistage procedures

  • Choi, Kiheon
    • Journal of the Korean Data and Information Science Society
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    • 제23권6호
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    • pp.1279-1287
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    • 2012
  • We particularly emphasized how to determine the number of replications with sequential and multistage procedures. So, the t-test is used to achieve some predetermined level of accuracy efficiently with loss function in the case of normal, chi-squared, an exponential distributions. We provided that the relevance of procedures are sequential procedure, two-stage procedure, modified two-stage procedure, three-stage procedure and accelerated sequential procedure. Monte Carlo simulation is carried out to obtain the stopping sample size that minimizes the risk.

칸반시스템에서 수요와 도착간격 변동에 따른 컨테이너 크기에 관한 시뮬레이션 연구 (A simulation study of container size based on the variance of demand and interarrival time in Kanban systems)

  • 손권익;함성호
    • 산업기술연구
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    • 제19권
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    • pp.301-312
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    • 1999
  • The purpose of this paper is to study the effects of container size with multi-stage and multi-item on average inventory and customer service level in Kanban systems. We use the different distributions of demand and interarrival time for each item to show that we had better to change the container size depending on different type of item for this simulation study. The small lot size can be used for container size of a single item if there is no setup time. The container size should be identical with average order size as setup time increases. The fill rate increases if the container size is large with multi-item. However, it is difficult to establish the effective container size because the effects of the container size on the order queue time are not clear. It is suitable to use the average order size as the container size for each item if the variance of demand and interarrival time of each item is relatively small. It is effective to sue the average container size if the variance of them is relatively large.

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통계적 추론에서의 표집분포 개념 지도를 위한 시뮬레이션 소프트웨어 설계 및 구현 (The Design and Implementation to Teach Sampling Distributions with the Statistical Inferences)

  • 이영하;이은호
    • 대한수학교육학회지:학교수학
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    • 제12권3호
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    • pp.273-299
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    • 2010
  • 본 논문의 목적은 고등학교 수준의 학생들이 표집분포의 개념을 학습할 수 있도록 '표집분포 시뮬레이션 (Sampling Distributions Simulation)'을 설계하고 구현하는 것이다. '표집분포 시뮬레이션'은 다음과 같이 4차시로 구성되어 있다. 1차시-신뢰도와 신뢰구간의 의미 학습하기 2차시-표집분포의 의미 학습하기 3차시-중심극한정리의 의미 학습하기 4차시-이항분포의 정규근사 학습하기 본 연구를 통하여 표집분포의 중요성에 대한 학생들이 인식이 달라지고 이해가 증진되기를 기대한다. 또 본 연구의 결과로 제공되는 프로그램 '표집분포의 시뮬레이션' 수업을 통해 통계적 추론 능력이 향상되고, 아울러 통계적 추론 속에서 표집 분포의 역할이 충분히 이해되기를 기대한다.

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여성 기성복 재킷의 치수 분석 - 신체치수와 제품치수의 비교를 중심으로 - (An Analysis of Body Measurement and Apparel Size for Woman's Ready-Made Jacket)

  • 조윤주;백경자;이정란
    • 한국의류산업학회지
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    • 제6권3호
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    • pp.347-356
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    • 2004
  • The purpose of this study is to analyze the sizing system and size designation of ready-made jackets for women. We survey the sizing system and size labeling that have been used and presently practiced by the domestic garment industry of ready-made woman's jacket. In addition, 264 tailored jackets are measured for the sake of this study. The jackets are classified into 3 groups(young, missy, and madame) according to the target age of the brand. The result shows that size labeling involves body measurements(85-94-160), size code(55, 66) or simplified letter(S, M, L). However, the correspondence of size information and ease tolerances of jackets is not consistent and each company has its own sizing system. There are significant differences among young, missy, and madame group on the bust girth of apparel in 66size code. The average apparel size piteh measurement distributions(bust girth and hip girth respectively) of young group are 9cm and 13cm in 55 size code, those of missy group are 7 em and 3 cm in 66 size code, and those of madame group are 6cm and 4cm in 77 size code. The ease of bust girth and hip girth in missy group are much more than other groups.

EBSD를 이용한 $SrTiO_3$의 입자 크기 및 입자 배향 분포 (EBSD studies of the grain size and grain orientation distribution of $SrTiO_3$)

  • 박명범;;조남희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.46-46
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    • 2006
  • $SrTiO_3$ was annealed at two different annealing times (1 h and 16 h) to investigate the annealing effect on the grain size and orientation distribution. Electron backscattered diffraction (EBSD) was used to analyze the grain size and grain orientation distributions of the $SrTiO_3$. It is possible to understand the annealing effect on the microstructure evolution, by comparing the grain size and orientation distribution of the $SrTiO_3$ as a function of annealing time.

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유전체 연관 연구에서의 검정력 및 연구대상수 계산 고찰 (A Review of Power and Sample Size Estimation in Genomewide Association Studies)

  • 박애경;김호
    • Journal of Preventive Medicine and Public Health
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    • 제40권2호
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    • pp.114-121
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    • 2007
  • Power and sample size estimation is one of the crucially important steps in planning a genetic association study to achieve the ultimate goal, identifying candidate genes for disease susceptibility, by designing the study in such a way as to maximize the success possibility and minimize the cost. Here we review the optimal two-stage genotyping designs for genomewide association studies recently investigated by Wang et al(2006). We review two mathematical frameworks most commonly used to compute power in genetic association studies prior to the main study: Monte-Carlo and non-central chi-square estimates. Statistical powers are computed by these two approaches for case-control genotypic tests under one-stage direct association study design. Then we discuss how the linkage-disequilibrium strength affects power and sample size, and how to use empirically-derived distributions of important parameters for power calculations. We provide useful information on publicly available softwares developed to compute power and sample size for various study designs.