• Journal of Ginseng Research
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• v.18 no.2
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• pp.134-136
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• 1994

The effects of soil phosphorus level on seed emergence, seedling mortality, plant and root development of American ginseng (Panax quinquefolium L.) were evaluated in a newly planted commercial ginseng garden. Phosphorus levels were increased from 58 ppm to 100, 150 and 200 ppm with triplephosphate (0-45-0). Higher phosphate levels increased, seed emergence and reduced seedling mortality. Root length, diameter, fresh root weight and total leaflet length were not affected by phosphate levels.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.2
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• pp.232-239
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• 1985

근사수평 이상반류유동에서의 플러딩천이에 대한 실험을 수행하였으며 이것을 바탕으로 반류유 동도(flow-regime map)를 완성하였다. 또 플러딩천이에 대한 응축의 영향을 고찰하였는데 플러 딩이 액체입구에서 야기될 때 플러딩 속도는 응축량을 고려한 유효증기량으로 표시되며 이 경우 반드시 히스테리시스효과를 동반하게 된다. 이 효과는 응축에 기인하는 것으로 그 메카니즘을 구명하였다. 또 전달액체유량이 영이 될 때의 임계증기속도는 액체분출유량이나 액체서브쿠울 링의 정도에 무관하며 본 연구에서 사용한 관의 경우, 수정 Wallis 변수로 1.74로 나타났다.

• Proceedings of the Korean Statistical Society Conference
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• 2001.11a
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• pp.89-94
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• 2001

In this study we focus on variable selection in decision tree growing structure. Some of the splitting rules and variable selection algorithms are discussed. We propose a competitive variable selection method based on Kruskal-Wallis test, which is a nonparametric version of ANOVA F-test. Through a Monte Carlo study we note that CART has serious bias in variable selection towards categorical variables having many values, and also QUEST using F-test is not so powerful to select informative variables under heavy tailed distributions.

• Communications for Statistical Applications and Methods
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• v.14 no.3
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• pp.551-560
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• 2007

Kruskal and Wallis (1952) proposed typical nonparametric method in one-way layout problem. A special feature of this procedure is use of rank in mixed samples. In this paper, the new procedure based on placement as extension of the two sample placement tests described in Orban and Wolfe (1982) was proposed. Some critical values in small sample cases and comparative results of a Monte Carlo power study are presented.

• Proceedings of the Safety Management and Science Conference
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• 2008.04a
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• pp.451-460
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• 2008

This paper reviews nonparametric statistics by Neyman-Pearson test and Fisher test. Nonparametric statistics deal with the small sample with distribution-free assumption in multi-product and small-volume production. Two tests for various nonparametric statistic methods such as sign test, Wilcoxon test, Mann-Whitney test, Kruskal-Wallis test, Mood test, Friedman test and run test are also presented with the steps for testing hypotheses and test of significance.

• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.853-855
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• 1994

The object of present note is to give a very short proof of Stirling's formula which uses only a formula for the generalized zeta function. There are several proofs for this formula. For example, Dr. E. J. Routh gave an elementary proof using Wallis' theorem in lectures at Cambridge ([5, pp.66-68]). We can find another proof which used the Maclaurin summation formula ([5, pp.116-120]). In [1], they used the Central Limit Theorem or the inversion theorem for characteristic functions. In [2], pp. Diaconis and D. Freeman provided another proof similarly as in [1]. J. M. Patin [7] used the Lebesgue dominated convergence theorem.

• Journal of the Ergonomics Society of Korea
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• v.31 no.1
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• pp.171-176
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• 2012

Objective: The goal of this study was to assess work ability of Korean workers in the shipbuilding industry. Background: Old age is associated with inevitable time-dependent losses in physical capabilities. However the maintenance of physical capabilities is essential for continuing independence in old age. The work ability index(WAI) was constructed to reveal how well a worker is able to perform his or her work. Method: The WAI is a kind of survey methods developed to estimate the work capacity of aged workers by the Finish Institute of Occupational Health(FIOH) in 1998. The difference of the WAI between groups in each category was tested using the Kruskal-Wallis test, and the relationship between the WAI and the workers' ages was tested by the Correlation test. Results: This study surveyed 2,709 persons working in the shipbuilding industry in Korea. The average WAI score for all workers was 40.0 denoting a Good Level. Also, workers in the shipbuilding industry had lower work ability, as compared to the results of other industries. The WAI was analyzed for different age groups(${\leq}29$; 30~34; 35~39; 40~44; 45~49; 50~54; ${\geq}55$). The results of Kruskal-Wallis test showed that significant difference was identified on the effect of aging(p<0.05). Conclusion: Advanced countries like the Finland showed decreasing tendency in good and excellent levels as aged, but there was no decreasing tendency in Korean population. The results may be attributable to the general characteristics of Korean society, such as poor social security and burden caused by role of the patriarch. It may bring forth higher work ability in aged population even their physical condition is getting worse. Application: This finding could be used for developing more accurate assessment tool of work ability for working environment.

• Journal of Digital Convergence
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• v.16 no.9
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• pp.219-228
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• 2018

The purpose of this study was to examine the influence of ethical values and ethical sensitivity on character in junior and senior nursing students. A total of 356 surveys were analyzed using SPSS version 20. T-test, ANOVA/Kruskal-Wallis test, Pearson correlation coefficients, and stepwise multiple regression analysis were used. The results of the study showed that the main factors influencing character was patient oriented care in ethical sensitivity (${\beta}=0.258$), followed by nurse-colleague relationship among ethical values (${\beta}=0.153$), religion (${\beta}=0.131$), professional responsibility in the ethical sensitivities (${\beta}=0.101$), and the above variables accounted for 43.3% of character (F=44.960, p<.001). This study confirmed that ethical values and ethical sensitivity are important variables affecting character and convergence course integrating above factors needs to be provided for nursing students.

• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.169-179
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• 2016

This study used three types of survey, an anxiety for practice, a career decision making self-efficacy, and a career decision level for students majoring in language rehabilitation in college in order to provide an effective guide for practice and career decision. By using 18.0 SPSS statistic package, the data has examined with Mann-Whitney test, Kruskal-Wallis test and Bonferroni test based on student's grade, academic record and practice duration. The result of study is as follows. First, based on grade, students showed significant differences on several subfactors of the anxiety for practice and the level of career decision-making. Second, based on an academic point and practice duration, there were significantly different in several subfactors of the anxiety for practice, the career decision-making self efficacy, the career decision level. Consequently grade, academic record and practice duration influenced student's conception for practice and career.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.308-322
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• 1991

A set of experiments of Counter-Current Flow Limit(CCFL or Flooding) was performed to improve the drawbacks of Wallis' Correlation which neglects the effects of channel size, channel length, injection method and the boundary conditions at the inlet of liquid and gas phase. In these experiments using water and air, the followings were found ; (i) The effects of channel size and length were quite significant. In large tubes(D>20mm), the flooding front occurred at the bottom of the channel and when the gas flow increased the front moved upward ; however, in small tubes(D<20mm), there were no upward movement of flooding front and the flooding just occurred at the liquid inlet. (ii) The effect of water inlet device was not as significant as that of channel length though the inlet boundary conditions could affect the flow development and flooding afterward. (iii) Once the flooding front reached the inlet of water injection device, an newly reduced flow condition was set up and resulted in another flooding corresponding to the new condition.