• Title/Summary/Keyword: Equality distribution ratio

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The Remodelling of Hydraulic Structure in a Distribution Channel for Improving the Equality of the Flow Distribution (II): Optimization through Wet Tests (수리구조 개선을 통한 분배수로 균등분배 성능 향상에 관한 연구(II): Pilot plant 실험을 통한 최적화)

  • Park, No-Suk;Kim, Seong-Su;Hwang, Jun-Sick;Im, Jae-Rim;Kim, Chung-Hwan
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.581-587
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    • 2007
  • In order to suggest the methodology for improving the equality of flow distribution in a distribution channel, wet tests were carried out for pilot plant which was scaled down to 1/8 of full scale distribution channel being operated in domestic K_water treatment plant. The correlation between various hydraulic variables and their effects on the equality of flow distribution was evaluated through wet tests using pilot plant. From the results of wet tests, the longitudinal baffle with orifices was installed in the distribution channel, the equality of flow distribution was improved on the condition that the Froude number in pilot plant was similar with that in the full scale channel. Also, the opening ratio of the orifices on the longitudinal baffled did not have influence on the performance of the equality of flow distribution when the average flow velocity and Froud number were relatively low (Froude number ${\fallingdotseq} 0.01$). In the other hand, the performance of the equality of flow distribution was improved with increasing the opening ration of on the longitudinal baffle under conditions of relatively high average flow velocity and high Froud number(${\gtrsim}0.1$)

The Remodelling of Hydraulic Structure in a Distribution Channel for Improving the Equality of the Flow Distribution (I): Design Using CFD Simulation (수리구조 개선을 통한 분배수로 균등분배 성능 향상에 관한 연구(I) : CFD를 이용한 설계 중심으로)

  • Park, No-Suk;Kim, Seong-Su;Park, Jong-Yoon;Yoon, Cheol-Hwan;Kim, Chung-Hwan
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.571-579
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    • 2007
  • This study was conducted to qualify the equality of the flow distribution from open channel between rapid mixing basin and flocculation basins in a domestic full-scale water treatment plant, and suggest a remedy for improving the equality. In order to evaluate the feasibility of the suggested remedy, computational fluid dynamics (CFD) technique are used, and for verifying the CFD simulation results wet tests were carried out for the pilot scale channel based on geometric similarity. From the results of CFD simulation and wet tests, it was investigated that the modification of hydraulic structure in the distribution channel, which is to install the longitudinal orifice baffle in flow direction, could improve the equality of the flow distribution. Also, in the case that Froude number is relatively small (Froude number <<0.03), the open ratio of orifices on the installed baffle hardly affects the equality of flow distribution.

Tests of equality of several variances with the likelihood ratio principle

  • Park, Hyo-Il
    • Communications for Statistical Applications and Methods
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    • v.25 no.4
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    • pp.329-339
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    • 2018
  • In this study, we propose tests for equality of several variances with the normality assumption. First of all, we propose the likelihood ratio test by applying the permutation principle. Then by using the p-values for the pairwise tests between variances and combination functions, we propose combination tests. We apply the permutation principle to obtain the overall p-values. Also we review the well- known test statistics for the completion of our discussion and modify a statistic with the p-values. Then we illustrate proposed tests by numerical and simulated data and compare their efficiency with the reviewed ones through a simulation study by obtaining empirical p-values. Finally, we discuss some interesting features related to the resampling methods and tests for equality among several variances.

Performance Analysis of a Vehicle Disinfector Nozzles Used at Livestock Farm (축산 차량소독기의 노즐 성능 분석)

  • Kim, W.;Lee, S. K.
    • Journal of Animal Environmental Science
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    • v.11 no.2
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    • pp.111-116
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    • 2005
  • The purpose of this study was to analyze the performance of vehicle disinfector nozzles using at the livestock farm. The nozzle of vehicle disinfectors was measured spraying rate and equality distribution ratio by pressures. The spraying rate of TK-I's nozzle was 1,605 ml/min at 3 MPa, TK-II's nozzle was 2,020 ml/min, JA's nozzle was 1,150 ml/min and IS's nozzle was 795 ml/min. The number of nozzles of TK-I's, TK-II's, JA's and IS's for reasonable spraying rate($25{\ell}/min$. at 3 MPa) was respectively 16, 13, 22 and 32 units. The equality distribution ratio of TK-I's nozzle by pressures was equalized and the nozzles of TK-II's, JA's and IS's was sprayed to the center or side more then other sides in the measured boxes.

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The Effects of Dispersion Parameters and Test for Equality of Dispersion Parameters in Zero-Truncated Bivariate Generalized Poisson Models (제로절단된 이변량 일반화 포아송 분포에서 산포모수의 효과 및 산포의 동일성에 대한 검정)

  • Lee, Dong-Hee;Jung, Byoung-Cheol
    • The Korean Journal of Applied Statistics
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    • v.23 no.3
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    • pp.585-594
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    • 2010
  • This study, investigates the effects of dispersion parameters between two response variables in zero-truncated bivariate generalized Poisson distributions. A Monte Carlo study shows that the zero-truncated bivariate Poisson and negative binomial models fit poorly wherein the zero-truncated bivariate count data has heterogeneous dispersion parameters on dependent variables. In addition, we derive the score test for testing the equality of the dispersion parameters and compare its efficiency with the likelihood ratio test.

On Testing Equality of Matrix Intraclass Covariance Matrices of $K$Multivariate Normal Populations

  • Kim, Hea-Jung
    • Communications for Statistical Applications and Methods
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    • v.7 no.1
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    • pp.55-64
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    • 2000
  • We propose a criterion for testing homogeneity of matrix intraclass covariance matrices of K multivariate normal populations, It is based on a variable transformation intended to propose and develop a likelihood ratio criterion that makes use of properties of eigen structures of the matrix intraclass covariance matrices. The criterion then leads to a simple test that uses an asymptotic distribution obtained from Box's (1949) theorem for the general asymptotic expansion of random variables.

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Statistical Inference Concerning Peakedness Ordering between Two Symmetric Distributions

  • Oh, Myong-Sik
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.1
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    • pp.201-210
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    • 2004
  • The peakedness ordering is closely related to dispersive ordering. In this paper we consider the statistical inference concerning peakedness ordering between two arbitrary symmetric distributions. Nonparametric maximum likelihood estimates of two distribution functions under symmetry and peakedness ordering are given. The likelihood ratio test for equality of two symmetric discrete distributions in the sense of peakedness ordering is studied.

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Noninformative priors for the ratio of parameters of two Maxwell distributions

  • Kang, Sang Gil;Kim, Dal Ho;Lee, Woo Dong
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.3
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    • pp.643-650
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    • 2013
  • We develop noninformative priors for a ratio of parameters of two Maxwell distributions which is used to check the equality of two Maxwell distributions. Specially, we focus on developing probability matching priors and Je reys' prior for objectiv Bayesian inferences. The probability matching priors, under which the probability of the Bayesian credible interval matches the frequentist probability asymptotically, are developed. The posterior propriety under the developed priors will be shown. Some simulations are performed for identifying the usefulness of proposed priors in objective Bayesian inference.

Computation of Noncentral T Probabilities using Neural Network Theory (신경망이론에 의한 비중심T분포 확률계산)

  • Gu, Son-Hee
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.1
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    • pp.177-183
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    • 1997
  • The cumulative function of the noncentral t distribution calculate power in testing equality of means of two normal populations and confidence intervals for the ratio of population mean to standard deviation. In this paper, the evaluation of the cumulative function of noncentral t distribution is applied to the neural network consists of the multi-layer perception structure and learning process has the algorithm of the backpropagation. Numerical comparisons are made between the Fisher's values and the results obtained by neural network theory.

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Comparison Density Representation of Traditional Test Statistics for the Equality of Two Population Proportions

  • Jangsun Baek
    • Communications for Statistical Applications and Methods
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    • v.2 no.1
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    • pp.112-121
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    • 1995
  • Let $p_1$ and $p_2$ be the proportions of two populations. To test the hypothesis $H_0 : p_1 = p_2$, we usually use the $x^2$ statistic, the large sample binomial statistic Z, and the Generalized Likelihood Ratio statistic-2log $\lambda$developed based on different mathematical rationale, respectively. Since testing the above hypothesis is equivalent to testing whether two populations follow the common Bernoulli distribution, one may also test the hypothesis by comparing 1 with the ratio of each density estimate and the hypothesized common density estimate, called comparison density, which was devised by Parzen(1988). We show that the above traditional test statistics ate actually estimating the measure of distance between the true densities and the common density under $H_0$ by representing them with the comparison density.

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