• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.221-222
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• 2015

Since the input data such as types and quantities of materials cannot be acquired during the planning and designing phases, it is difficult to estimate the carbon emissions from the construction phase. As the materials are closely related to the building usages, an approximate estimation by the usages can be suggested. However, before confirming the estimation, the difference test among the carbon emissions of the building usages should be implemented. This study executed t-test or Mann-Whitney test between apartments and schools. The result of the study statistically verified the significant difference between the carbon emissions of apartments and schools.

• The Korean Journal of Applied Statistics
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• v.22 no.6
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• pp.1249-1263
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• 2009

The power function in sample size determination has to be characterized by an appropriate statistical test for the hypothesis of interest. Nonparametric tests are suitable in the analysis of ordinal data or frequency data with ordered categories which appear frequently in the biomedical research literature. In this paper, we study sample size calculation methods for the Wilcoxon-Mann-Whitney test for one- and two-dimensional ordinal outcomes. While the sample size formula for the univariate outcome which is based on the variances of the test statistic under both null and alternative hypothesis perform well, this formula requires additional information on probability estimates that appear in the variance of the test statistic under alternative hypothesis, and the values of these probabilities are generally unknown. We study the advantages and disadvantages of different sample size formulas with simulations. Sample sizes are calculated for the two-dimensional ordinal outcomes of efficacy and safety, for which bivariate Wilcoxon-Mann-Whitney test is appropriate than the multivariate parametric test.

• Journal of Korea Port Economic Association
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• v.32 no.4
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• pp.73-87
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• 2016

The purpose of this study is to investigate the empirical results of Analytic Hierarchy Process/Data Envelopment Analysis-Assurance Region(AHP/DEA-AR) by using multiple regression analysis during the period of 2009-2012 with 5 inputs (number of gantry cranes, number of berth, berth length, terminal yard, and mean depth) and 2 outputs (container TEU, and number of direct calling shipping companies). Assurance Region(AR) is the most important tool to measure the efficiency of seaports, because individual seaports are characterized in terms of inputs and outputs. Traditional AHP and multiple regression analysis techniques have been used for measuring the AR. However, few previous studies exist in the field of seaport efficiency measurement. The main empirical results of this study are as follows. First, the efficiency ranking comparison between the two models (AHP/DEA-AR and multiple regression) using the Wilcoxon signed-rank test and Mann-Whitney signed-rank sum test were matched with the average level of 84.5 % and 96.3% respectively. When data for four years are used, the ratios of the significant probability are decreased to 61.4% and 92.5%. The policy implication of this study is that the policy planners of Korean port should introduce AHP/DEA-AR and multiple regression analysis when they measure the seaport efficiency and consider the port investment for enhancing the efficiency of inputs and outputs. The next study will deal with the subjects introducing the Fuzzy method, non-radial DEA, and the mixed analysis between AHP/DEA-AR and multiple regression analysis.

• Journal of the Korean Magnetics Society
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• v.26 no.3
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• pp.105-114
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• 2016

In this study, For assessment of triangular fibrocartilage complex (TFCC) injury, we acquired images by fat suppressed 3D fast spoiled gradient recalled T1 and fat suppressed Isotropic 3D fast spin echo T1 techniques. For quantitative evaluation, measured signal to noise ratio and contrast to noise ratio and verified statistical significance between two imaging techniques by Mann-Whitney U verification. And for qualitative evaluation, marked 4-grade scoring (0: non diagnostic, 1: poor, 2: adequate, 3: good) on shape of TFCC, artifacts by partial volumes, description of the lesions by two radiologist, verified coincidence between 2 observer using Kappa-value verification. We used 3.0 Tesla MR equipment and 8-channel RF coil for imaging acquisition. As quantitative evaluation results, signal to noise ratio and contrast to noise ratio value of Isotropic 3D fast spin echo T1 technique is higher in every image sections, also between two imaging techniques by Mann-Whitney U verification was statistically significant (p < 0.05). As qualitative results, observer 1, 2 marked a higher grade on Isotropic 3D FSE T1 technique, coincidence verification of evaluation results between two observers by Kappa-value verification was statistically significant (p < 0.05). As a result, during MRI examination on TFCC injury, fat suppressed Isotropic 3D fast spin echo T1 technique is considered offering more useful information about abnormal lesion of TFCC.

• 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.

• Pediatric Infection and Vaccine
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• v.30 no.1
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• pp.12-19
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• 2023

Purpose: Sepsis is the most common cause of neonatal death accounting for 30-50% of mortality annually in developing countries. This study was to determine the prognostic factors of neonatal sepsis mortality. Methods: A retrospective cohort was conducted in Dr. R. Sosodoro Djatikoesoemo Governor Hospital from April 2021 to September 2021 on 121 neonates in the neonatal intensive care unit (NICU) diagnosed with sepsis. The inclusion criteria were neonates aged 0-28 days, admitted to the NICU, and diagnosed with sepsis. The exclusion criteria were incomplete data and the presence of congenital abnormalities. A χ² test was performed on the sex, gestational age, mode of delivery, birth weight, APGAR score, birthplace, and blood culture. A normality test was performed on leukocytes, lymphocytes, neutrophils, platelets, C-reactive protein (CRP), and length of stay. Then performed a Mann-Whitney test. Results: Birth weight (P=0.038), gestational age (P=0.009), and blood culture (P=0.014) showed a significant relationship with the neonatal sepsis outcome while Mann-Whitney test showed significant differences in the platelets (P=0.018), CRP (P=0.002), and length of stay (P<0.001). Multivariate analysis showed that 3 prognostic factors associated with neonatal sepsis mortality were prematurity (odds ratio [OR], 3.906; 95% confidence interval [CI], 1.344-11.356; P=0.012), low birth weight (LBW, OR, 2.833; 95% CI, 1.030-7.790; P=0.044), and gram-negative bacteria (OR, 4.821; 95% CI, 1.018-22.842; P=0.047). Conclusions: Prematurity, LBW, and gram-negative bacteria were associated with the prognostic factors of neonatal sepsis.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.619-629
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• 2022

This study aims to investigate the relationship among public service motivation, hospital organizational culture type, job-esteem, and turnover intention of public hospital nurses. A cross-sectional study was conducted on 124 nurses at four public hospitals in the Gyeonggi Province (Icheon, Anseong, Suwon, Paju). Data were analyzed using descriptive statistics, t-tests, ANOVA, and Pearson correlation coefficient. Mann-Whitney U test and the Kruskal-Wallis test were used with the Bonferroni test for post hoc comparison when the data were not normally distributed. The turnover intention of the subjects was public service motivation (r=-.30, p<.001), affiliative culture (r=-.28, p=.002), innovative culture (r=-.34, p< .001) and task culture (r=-.30, p=.001) were negatively correlated. Study findings suggest that public service motivation must be increased to reduce the turnover intention of nurses in public hospitals.

• The Korean Journal of Applied Statistics
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• v.30 no.4
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• pp.513-528
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• 2017

Statistics are often used to test two samples if they have been drawn from the same underlying distribution. In this paper, we introduce several well-known distribution-free tests to compare distributions and conduct an extensive Monte-Carlo simulation to specify their behaviors. We consider various circumstances of when two distributions vary in (1) location, (2) scale, (3) symmetry, (4) kurtosis, (5) tail weight. A practical guideline for two-sample goodness-of-fit test is presented based on the simulation result.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.115-122
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• 2018

The purpose of this study is to compare student evaluation methods in team based learning classes for dental hygiene students. The subjects of this study were the score of dental hygiene students who took the courses of 'oral health education practice'. The analysis methods were spearman correlation analysis, skewness, kurtosis and Mann-Whitney U test. As a result, there was a significant correlation between the self-evaluation and peer-evaluation. Self-evaluation showed lenience tendency rather than peer-evaluation and self-evaluation found the highest central tendency. The peer-evaluation result was more lenience and more central in the group where self-evaluation was performed.

• Proceedings of the Korean Statistical Society Conference
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• 2004.11a
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• pp.111-116
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• 2004

스트레스 수준이 논을 것으로 예상되는 공군사관학교 수험생의 신체검사 결과로부터 신체건강 지표인 혈액 내 생화학적 요인들과 정신건강 지표인 다면 인성검사 점수를 추출하여 통계적 상관성 및 유의성을 비교 분석하였다 사관생도들 중 $10\%$의 표본을 추출하여 사관생도와 수험생 집단간의 특성 비교를 위한 비교집단으로 이용하였다. 수험생과 사관생도 집단 간의 특성 요인 비교는 Mann-whitney U 검정과 Kruskal-Wallis 검정을 이용하였다. 수험생 집단 내에서 혈중 요인 및 정신건강 지표인 MMPI 점수는 정상범주에 있었고 두 요인 간 상관성은 발견할 수 없었다. 그러나 사관생도와 수험생 집단 간의 특성 요인들에 대한 유의성 검정 결과, 특히 2학년생도들의 혈액 내 혈구 수 및 활동성 또는 적극성과 관련된 MMPI 하위척도에서 수험생 집단과 매운 유의한 차이를 보이는 특이한 현상을 발견할 수 있었고 이에 대한 해석을 언급하였다.