• Proceedings of the Korean Reliability Society Conference
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• 2000.11a
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• pp.365-371
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• 2000

The problem of trend change in the failure rate is great interest in the reliability and survival analysis. In this paper we develop a test statistic for testing whether or not the failure rate changes its trend using random censored data. The asymptotic normality of the test statistic is established. We discuss the efficiency values of loss due to censoring.

• International Journal of Quality Innovation
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• v.1 no.1
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• pp.58-63
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• 2000

The problem of trend change in the failure rate is great interest in the reliability and survival analysis. In this paper we develop a test statistic for testing whether or not the failure rate changes its trend using random censored data. The asymptotic normality of the test statistic is established. The efficiency values of loss due to censoring are discussed.

• Communications for Statistical Applications and Methods
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• v.8 no.1
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• pp.185-192
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• 2001

Using the Lorenz curve that is proved to be a powerful tool to measure the income inequality within a population of income receivers, we propose the normalized sample Lorenz curve for the goodness-of-fit test that is very important test in statistical analysis. For two hodgkin's disease data sets, we compare the Q-Q plot and the proposed normalized sample Lorenz curve.

• Journal of Korean Medicine Rehabilitation
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• v.31 no.4
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• pp.157-166
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• 2021

Objectives This study is designed to evaluate the safety of Bojungikgi-tang soft extract in healthy male volunteers. Methods 12 healthy male volunteers were recruited and this study was carried out by a single center. Laboratory test results, vital signs of the volunteers were collected to evaluate safety. According to registration order, the 12 subjects were allocated by serial number. To evaluate safety, blood samples were taken and vital signs were checked 4 times - screening, pre administration, post administration and follow up-during the whole trial. The difference between pre (before medication [0 hr]) and post-administration (after medication [48 hr]) variables was summarized as mean±standard deviation. The normality test was performed using the Kolmogorov-Smirnov test and Shapiro-Wilk test. When the normality is satisfied, the paired t-test is applied. Otherwise, the non-parametric method, Wilcoxon signed rank test is applied. The significance level was p<0.05. The incidence of all adverse effects are shown in percentage. Results In the case of red blood cell, hemoglobin, hematocrit, lymphocytes, neutrophils, protein, γ-glutamyl transpeptidase values, the normality test result of the variable for the difference value before and after the dosing has a significance level <0.05. But most of values did not deviate from the normal range, and the deviation from the normal range could not be regarded as the significance associated with this clinical trial. And adverse event wasn't observed associated with the clinical trial drug. Conclusions Bojungikgi-tang soft extract were considered to be safe for healthy male volunteers.

• Journal of Korean Institute of Industrial Engineers
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• v.10 no.2
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• pp.51-65
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• 1984

A process quality control system is designed which incorporates run tests, normality test, process capability studies, etc., into control chart scheme, and a software package for microcomputers is developed. The system is interactive and has data base management capabilities. All programs are written in BASIC language.

• The Journal of Korean Physical Therapy
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• v.31 no.1
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• pp.31-34
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• 2019

Purpose: This study examined the effects of the fascial distortion model (FDM) method on Cobb's angle. Methods: Fourteen subjects participated in this study. The idiopathic scoliosis group performed FDM treatments eight times in four weeks. A Shapiro-Wilks test was used to verify the normality of a group of idiopathic scoliosis patients. A paired t-test was performed to determine the satisfaction with the normality. Results: The difference in Cobb's angle was reduced significantly (p<0.05) by an average of $5.72^{\circ}{\pm}2.24$ from $15.51^{\circ}{\pm}1.81$ before the experiment. Conclusion: This study found that the use of the FDM method was effective in improving the Cobb's angle. The application of a FDM treatment appears to stabilize the fascia with decreased ability to adapt physiologically. The application of the CD and TB method of FDM treatment improved the asymmetry spine by dispersing moisture in fascia and improving the contraction and relaxation ability. The results suggest that the Cobb's angle is reduced when FDM is applied, thereby preventing the progression of curvature and avoiding psychological and physical problems that can arise from improving patients with scoliosis.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.2
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• pp.53-62
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• 2020

This study is to evaluate the accuracy of the meteorological information provided for the aircraft operating at low altitude. At first, it is necessary to identify crucial elements of weather information closely related to flight safety during low altitude flights. The study conducted a survey of pilots of low altitude aircraft, divided into pre-flight and in-flight phases, and reached an opinion that wind direction, wind speed, cloud coverage and ceiling and visibility are important items. Related to these items, we compared and calculated the accuracy of TAFs and METARs from Taean Airfield, Seosan Airport and Gunsan Airport because of their high number of domestic low-altitude flights. Accuracy analysis evaluated the accuracy of two numerical variables, Mean Absolute Error(MAE) and Root Mean Square Error(RMSE), and the cloud coverage which is categorical variable was calculated and compared by accuracy. For numeric variables, one-way ANOVA, which is a parameter-test, was approached to identify differences between actual forecast values and observations based on absolute errors for each item derived from the results of MAE and RMSE accuracy analyses. To determine the satisfaction of both normality assumptions and equivalence variability assumptions, the Shapiro-Wilk test was performed to verify that they do not have a normality distribution for numerical variables, and for the non-parametric test, Kruscal-Wallis test was conducted to determine whether or not they are satisfied.

• Journal of Korean Medicine Rehabilitation
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• v.34 no.3
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• pp.89-96
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• 2024

Objectives This study is designed to evaluated the safety of peony root extract tablet in healthy male volunteers. Methods 12 healthy male volunteers were recruited, and this study was conducted by a single center. The safety was evaluated by collecting laboratory test and vital signs of volunteers. As the registration process, 12 subjects were assigned by serial number. To evaluate safety, vital signs were checked and blood samples were collected 4 times during the screening period, pre & post-administration (after 8 hours) and post-administration (after 7 days). The difference in variables was summarized by the mean±standard deviation. The normality test was carried out using the Shapiro-Wilk test and Kolmogorov-Smirnov test. When normality is fulfilled, a paired t-test is applied and the significance level was p<0.05. And the incidence of all adverse effects and serious adverse effects are shown in percentage. Results In the case of vital sign, body temperature (BT) (℃) was 0.06±0.05 ℃ (p=0.008), and there was a statistically significant difference in before and after administration. However, clinical symptoms were not occurred and BT (℃) of all subjects before and after administration showed values within the normal reference value. There was no significant difference from the control group in all other vital signs and laboratory test data. And no side-effects associated to clinical trial drugs were followed. Conclusions The peony root extract tablet was considered to be safe for healthy male volunteers.

• Communications for Statistical Applications and Methods
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• v.3 no.3
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• pp.25-30
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• 1996

In discriminant analysis the procedures commonly used to estimate the dimensionality involve testing a sequence of dimensionality hypotheses. There is a problem with the size of the test since dimensionality hypotheses are tested sequentially and thus they are actually conditional tests. The focus of this paper is to investigate in asymptotic sense what happens to the sequential testing procedure if the assumption of normality does not hold.

• International Journal of Reliability and Applications
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• v.9 no.1
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• pp.71-78
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• 2008

Based on the goodness of fit approach, a new test is presented for testing exponentiality versus exponential better (worse) than used (EBU (EWU)) class of life distributions. The new test is much simpler to compute, asymptotically normal, enjoys good power and performs better than previous tests in terms of power and Pitman asymptotic efficiencies for several alternatives.