• 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(${\gtrsim}0.1$)

• Journal of the Korean Statistical Society
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• v.34 no.1
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• pp.35-38
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• 2005

A single, tractable, special case of the problem of continuous mixtures of beta distributions over their parameters is considered. This is the uniform mixture of generalized arc-sine distributions which, curiously, turns out to be linked by transformation to the Cauchy distribution.

• Journal of Astronomy and Space Sciences
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• v.4 no.2
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• pp.89-94
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• 1987

By using the recently determined color excess and distance data of classical by Kim (1985), the distribution of interstellar reddening material was studied to see the general picture of the average rate of interstellar absorption out to about 7-8 kpc in the Galactic plane in various directions from the sun.

• The Korean Journal of Malacology
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• v.13 no.2
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• pp.117-123
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• 1997

S study on the distribution of land snails in Kangweon-Do was carried out from May 1990 to July 1995. Mirus sp, and Aegista gottschei kongoensis were unrecorded in Korea and south Korea, respectively, As a result of this stududy, 21 families and 62 species of land snails are reported from Kangweon-Do, Korea.

• Journal of Korean Society for Quality Management
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• v.46 no.3
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• pp.509-522
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• 2018

Purpose: The purpose of this study was to propose more accurate mathematical model which can represent result of government quality assurance activity, especially corrective action and flaw. Methods: The collected data during government quality assurance activity was represented through histogram. To find out which distributions (Poisson distribution, Zero-Inflated Poisson distribution) could represent the histogram better, this study applied Pearson's correlation coefficient. Results: The result of this study is as follows; Histogram of corrective action during past 3 years and Zero-Inflated Poisson distribution had strong relationship that their correlation coefficients was over 0.94. Flaw data could not re-parameterize to Zero-Inflated Poisson distribution because its frequency of flaw occurrence was too small. However, histogram of flaw data during past 3 years and Poisson distribution showed strong relationship that their correlation coefficients was 0.99. Conclusion: Zero-Inflated Poisson distribution represented better than Poisson distribution to demonstrate corrective action histogram. However, in the case of flaw data histogram, Poisson distribution was more accurate than Zero-Inflated Poisson distribution.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1713-1714
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• 2006

This paper aims to analyze the overvoltage in underground distribution systems when lightning surge strikes to overhead line. The model is established by EMTP/ATPDraw for actual distribution systems. Simulation is carried out considering variation of parameters such as length and lightning current.

• Korean Journal of Veterinary Service
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• v.19 no.2
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• pp.139-153
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• 1996

Porcine E coli infection is a disease caused by Enterotoxin produced by Enterotoxigenic Escherichia coli(ETEC). Enteric colibacillosis has become an economically important disease in pigs as a result of increasing intensification of farrowing management. The present study undertaken to obtain the antibiotic sensitivity and distribution of serogroups and pili producibility test of ETEC from E. coli isolates in Chonnam. The results obtained were as follows. 1. A total of 71 isolates identified as E, coli employing IMViC system from rectal specimens of 54 piglets with diarrhea. 2. In antibiotic sensitivity test, isolates showed high sensitivity to AN, CM, Fox, GM, but resistance to EM, NA TC. 3. The distribution of 25 Isolates of serogroups were 0141:K85(11.3%), 08:K87(8.5%), 064:K (5.6%), 0138:K8l (4.2%), 0139 :K82(2.8%), 0157:K88ac(1.4%) and 0149:K9l (1.4%). 4. MRHA of guinea pig erythrocytes was detected in 8 out of 25OK serotypes and 9 out of 46 unidentified serotypes. MRHA titers of serotypes showed from 64 to 128 in 0141: K85, 2 in 0138:K8l and no titers in 0139:K82. 5. The production of heat labile enterotoxin of ETEC was detect 39 out of 52 isolates showed $\beta$-hemolysin, 7 out of 52 isolates showed ${\gamma}$-hemolysin and 6 out of 52 isolates showed ${\gamma}$-hemolysin by $GM_1$ganglioside ELISA. The distribution of LT toxin were in 12 isolate showed $\beta$-hemolysin, 2 isolates showed ${\alpha}$-hemolysin and 3 isolates showed ${\gamma}$-hemolysin in 25 OK serotypes.

• Journal of Environmental Impact Assessment
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• v.6 no.1
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• pp.111-119
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• 1997

This study was carried out to suggest the best statistical test which may be used to quantify the change of water quality between two groups. Traditional t-test may not be used in cases where the normality of underlying population distribution is not assured. Three non-parametric tests which are based on the relative order of the measurements, were studied to find out the applicability in water quality data analysis. The sign test is based on the sign of the deviation of the measurement from the median value, and the binomial distribution table is used. The signed rank test utilizes not only the sign but also the magnitude of the deviation. The Wilcoxon rank-sum test which is basically same as Mann-Whitney test, tests the mean difference between two independent samples which may have missing data. Among the three non-parametric tests studied, the singed rank test was found out to be applicable in the quantification of the change of water quality between two samples.

• Journal of the Korean GEO-environmental Society
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• v.15 no.4
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• pp.13-27
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• 2014

Catchments soil erosion, one of the most serious problems in the mountainous environment of the world, consists of a complex phenomenon involving the detachment of individual soil particles from the soil mass and their transport, storage and overland flow of rainfall, and infiltration. Sediment size distribution during erosion processes appear to depend on many factors such as rainfall characteristics, vegetation cover, hydraulic flow, soil properties and slope. This study involved laboratory flume experiments carried out under simulated rainfall in a 3.0 m long ${\times}$ 0.8 m wide ${\times}$ 0.7 m deep flume, set at $17^{\circ}$ slope. Five experimental cases, consisting of twelve experiments using three different sediments with two different rainfall conditions, are reported. The experiments consisted of detailed observations of particle size distribution of the out-flow sediment. Sediment water mixture out-flow hydrograph and sediment mass out-flow rate over time, moisture profiles at different points within the soil domain, and seepage outflow were also reported. Moisture profiles, seepage outflow, and movement of overland flow were clearly found to be controlled by water retention function and hydraulic function of the soil. The difference of grain size distribution of original soil bed and the out-flow sediment was found to be insignificant in the cases of uniform sediment used experiments. However, in the cases of non-uniform sediment used experiments the outflow sediment was found to be coarser than the original soil domain. The results indicated that the sediment transport mechanism is the combination of particle segregation, suspension/saltation and rolling along the travel distance.

• Journal of Distribution Science
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• v.14 no.5
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• pp.107-114
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• 2016

Purpose - Loading can decrease the productivity due to the possibility of carrying out with the opposite order of storage in container terminal. When the container is to be taken out, it is needed to move the container stacked upon the container to be carried out to other place temporarily. It is called as rehandling. Remarshalling, with the loading plan, is the arranging the containers before the ship arrives in order to avoid the rehandling during the carrying out. The present study tried to find out the factors affecting the efficiency when building the remarshalling plan with the utilization of neighboring storage space as a outer slot, and analyzed the efficiency of several remarshalling algorithms with the combination of those factors. Research design, data and methodology - The present study used, when the remarshalling plan is prepared for utilizing the outer slot, the simulation methods in order to compare the efficiency of the remarshalling algorithms which made with the factors affecting the efficiency. The factors affecting the efficiency are the method of making the child node, method of arrangement, and possibility of application of FIX. In order to analyze the affecting factors on the efficiency, several algorithms are prepared with the combination of production of the child node and the arrangement method with the availability of FIX application. With this algorithm, the effect of the factors on the efficiency after building up of remarshalling plan with the target on the bay with 10 rows, 8 columns, and 10 indices. Results - The method of rearrangement and making of a child node as the factor affecting the efficiency of remarshalling utilization of the outer bay were studied. It is efficient to combine the method of making a child node with MCS in order to reduce the number of moving the containers. For reducing the time in carrying out, it was found that all arrangement methods should be combined with RCS for the efficiency. The result of experiment shows the application of FIX with good result in case of succession ratio. In addition, when FIX was not applied, all of the most combinations resulted in short time in remarshalling. As a result, it can be concluded that the algorithm with proper combination of making the child node and the arrangement can increase the job efficiency based on the importance. Conclusion - The present study suggested and analyzed the algorithms with the combination of the arrangement method, the making of child node, and FIX. It is needed to develop the algorithm to judge the possibility whether the best remarshalling plan can be built or not within the bay in order to find a better method between the two cases such as within the bay and outer the bay. As a method for extending the study on the factors affecting the efficiency, it is possible to find out the way to build the remarshalling plan within the permitted time under any storage situation.