• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2771-2788
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• 2020

Experiments are conducted to study bubble flow behavior during the instability of subcooled boiling under uniform and non-uniform transverse heating. The non-uniform heat distribution introduces nonuniform bubble generation and condensation rates on the heated surface, which is different from the uniform heating. These bubble generation and condensation characteristics introduce a non-uniform local pressure distribution in the transverse direction, which creates an extra non-uniform pressure on the flowing bubbles. Therefore, different bubble flow behavior can be observed between uniform and non-uniform heating conditions. In the uniform heating, bubble velocity fluctuations are low, and the bubbles travel straight along the axial direction. In the non-uniform heating, more fluctuation in the bubble velocity occurs at low mass flow rate and high subcooled inlet temperatures, and reverse flow is observed. Additionally, the bubbles show a zigzag trajectory when they pass through the channel, which indicates the existence of cross flow in the transverse direction.

• Journal of the Korean Data and Information Science Society
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• v.20 no.4
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• pp.733-740
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• 2009

We obtain a skewed uniform distribution by a uniform distribution, and evaluate its coeffcient of skewness. And we obtain the approximate maximum likelihood estimator (AML) and moment estimator of skew parameter in the skewed uniform distribution. And we compare simulated mean squared errors (MSE) of those estimators, and also compare MSE of two proposed reliability estimators in two independent skewed uniform distributions each with different skew parameters.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.3
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• pp.479-487
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• 1987

In order to predict the effects of droplets distributions such as number density and droplets size on group combustion characteristics and flame structure for liquid fuel sprays, modifications of group combustions model were made by changing the droplets distributions from uniform to non-uniform. Various droplets distribution models were adopted in this analysis to examine the effect of number density distribution on combustion characteristics and the difference between uniform and non-uniform droplets size distributions for a spherical droplets cloud. As results of present study, hollow droplets could with outer concentrating distribution has shorter total combustion time compare with the case of solid droplets cloud with inner concentrating distribution. Uniform droplets size distribution model predicts the shorter total combustion time compare with non-uniform droplets size distribution model, and the uniform droplets size distribution model may be used to predict the total combustion time for the droplets cloud containing larger initial size of droplets.

• Journal of the Korean Data and Information Science Society
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• v.11 no.2
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• pp.319-325
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• 2000

In this paper, we shall derive MLE's, modified MLE, MRE and UMVUE's of the shape and scale parameters in a generalized uniform distribution, and propose several estimators for the right-tail probability in a generalized uniform distribution using the proposed estimators for the shape and scale parameters. And we shall compare exactly MSE of the proposed estimators for the shape and the scale parameters, and compare numerically efficiencies for the several proposed estimators of the right-tail probability in a generalized uniform distribution by Monte Caslo methods.

• Solar Energy
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• v.20 no.1
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• pp.97-108
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• 2000

The purpose of this study is to minimize the heat transfer surface area and cold fluid exit temperature of heat exchanger which applied to the refrigeration and air-conditioning system by utilizing the thermoelectric principle. Both uniform and non-uniform current distribution methods which applied to the analysis of the TE elements that incorporates heat exchanger were investigated. The non-uniform current distribution method had the better coefficient of performance and had the lower cold fluid exit temperature of the TE cooling system than the uniform current distribution method. It was found that if a TE cooling system incorporates a heat exchanger, a non-uniform current distribution should guarantee to the lowest cold fluid exit temperature. Also, the hybrid method (combination of the uniform and non-uniform current distribution method) is investigated to achieve the best results by combining the uniform and non-uniform current distributions. The results show that it can lower the cold fluid exit temperature and reduce the heat transfer surface area for the parallel flow arrangement if we apply the constant current in some entry region and the non-uniform increasing current in the direction of the cold fluid flow afterwards.

• Journal of applied mathematics & informatics
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• v.28 no.5_6
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• pp.1573-1581
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• 2010

we investigate the n-fold convolution of the uniform distributions. First, we are concerned with the explicit distribution function of the partial sum ${\zeta}_n$ when the random variables are independent and has identically uniform distribution, next, we determine the n-fold convolution distribution of ${\zeta}_n$ when the identically distributed condition is not satisfied.

• Communications for Statistical Applications and Methods
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• v.15 no.3
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• pp.325-332
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• 2008

We consider estimation of reliability P(Y < X) and distribution of the ratio when X and Y are independent uniform random variable and power function random variable, respectively and also consider the estimation problem when X and Y are independent uniform random variable and a half-normal random variable, respectively.

• Journal of applied mathematics & informatics
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• v.37 no.5_6
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• pp.351-355
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• 2019

We obtain two characterizations of uniform distribution based on ratios of upper record values by the properties of independence and identical distribution.

• Journal of the Korean Statistical Society
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• v.10
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• pp.97-104
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• 1981

It is shown that a lattice distribution defined on a set of n lattice points $L(n,\delta) = {\delta,\delta+1,...,\delta+n-1}$ is a distribution induced from the distribution of convolution of independently and identically distributed (i.i.d.) uniform [0,1] random variables. Also the m-th moment of the lattice distribution is obtained in a quite different approach from Park and Chung (1978). It is verified that the distribution of the sum of n i.i.d. uniform [0,1] random variables is completely determined by the lattice distribution on $L(n,\delta)$ and the uniform distribution on [0,1]. The factorial mement generating function, factorial moments, and moments are also obtained.

• Journal of the Korean Society of Costume
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• v.56 no.5 s.104
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• pp.75-88
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• 2006

The conception of uniform is changing from function and economical efficiency of the past to symbolism and aesthetic sense So, in such a management strategical point of view as enterprises' PR, scouting talent, organization revitalization etc, this is required to settle uniform culture which is proper to each enterprise and design development. The purpose of this thesis is, first, to study to help distribution enterprises' CI or PR by examining the present condition of uniform design in domestic fashion distribution enterprise and planning uniform design on the base of real case and finally making a real thing in person. Second is to suggest to fashion enterprise security of competitive ability of uniform-producing enterprise by developing article design of worth. Third is to present academic area with how to do design education in a wide range not based on trend article development. Following is how and what to study to carry out these purposes. Details about necessity and how and what to study are in an introduction, the conception of uniform in theory through precedential records examination in chapter 2, the present condition of uniform design based on Changwon city in chapter 3, planning uniform design and making a real thing suitable for F enterprise in chapter 4, and the conclusion is in chapter 5. Through this study, I became to know that uniform in distribution enterprise who treats visitors face to face is very important. I supply material and information concluded from this study to uniform industry and hope this will be helpful in developing uniform. It is significant in that this study as being related with enlarged uniform and enterprise, beyond such a uniform area as school uniform and hospital one, expanded the study range of clothing. I already tell you that this study is based on visual expression of uniform and wearer's feeling in clothes is not included.