• Structural Engineering and Mechanics
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• 제17권1호
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• pp.29-50
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• 2004

A total life model was developed to assess the service life of aging aircraft. The primary focus of this paper is the development of crack growth life projection using the response surface method. Crack growth life projection is a necessary component of the total life model. The study showed that the number of load cycles N needed for a crack to propagate to a specified size can be linearly related to the geometric parameter, material, and stress level of the component considered when all the variables are transformed to logarithmic values. By the Central Limit theorem, the ln N was approximated by Gaussian distribution. This Gaussian model compared well with the histograms of the number of load cycles generated from simulated crack growth curves. The outcome of this study will aid engineers in designing their crack growth experiments to develop the stochastic crack growth models for service life assessments.

• Journal of the Korean Data and Information Science Society
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• 제25권6호
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• pp.1521-1530
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• 2014

The ROC analysis is considered for multiple class diagnosis. There exist many criteria to find optimal thresholds and measure the accuracy of diagnostic tests for k dimensional ROC analysis. In this paper, we proposed a diagnostic accuracy measure called the correct classification simple rate, which is defined as the summation of true rates for each classification distribution and expressed as a function of summation of sequential true rates for two consecutive distributions. This measure does not weight accuracy across categories by the category prevalence and is comparable across populations for multiple class diagnosis. It is found that this accuracy measure does not only have a relationship with Kolmogorov - Smirnov statistics, but also can be represented as a linear function of some optimal threshold criteria. With these facts, the suggested measure could be applied to test for comparing multiple distributions.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권4호
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• pp.188-194
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• 2005

There are many factors that affect on the system output of Photovoltaic(PV) power generation; the variation of solar radiation, temperature, energy conversion efficiency of solar cell etc. This paper suggests a methodology for calculation of PV generation output using the probability distribution function of irradiance, PV array efficiency and revision factors of solar cell conversion efficiency. Long-term irradiance data recorded every hour of the day for 11 years were used. For goodness-fit test, several distribution (unctions are tested by Kolmogorov-Smirnov(K-S) method. The calculated generation output with or without revision factors of conversion efficiency is compared with that of CMS (Centered Monitoring System), which can monitor PV generation output of each PV generation site.

• 간호행정학회지
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• 제21권1호
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• pp.122-132
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• 2015

Purpose: This study was conducted to test the effect of Image Making Programs on image making efficacy, positive thinking, self-esteem, and nursing professionalism in nursing students. Methods: A non-equivalent control group pretest-posttest design was used. Participants were 124 nursing students at two universities, and were assigned to the treatment group (n=62) or the comparison group (n=62). The treatment was the Image Making Program, which was held twice over 2 days for 120 minutes per session. Data were collected from August to September 2012, and were analyzed using descriptive statistics, Kolmogorov-Smironov test, ${\chi}^2$-test, independent t-test, Mann-Whitney U test, one-tailed Mann-Whitney U test, independent one-tailed t-test with the SPSS/WIN 21.0 program. Results: Nursing students in the treatment group showed statistically significantly higher levels of image making efficacy, positive thinking, and nursing professionalism than those in the comparison group. Conclusion: The results indicate that the Image Making Program is an effective intervention for increasing image making efficacy, positive thinking, and nursing professionalism in nursing students. However, further research and practices are needed in this area.

• 한방재활의학과학회지
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• 제33권1호
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• pp.77-85
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• 2023

Objectives This study is designed to evaluate the safety of palmul-tang soft extract in healthy male volunteers. Methods Twelve healthy male volunteers were recruited. And this study was conducted in a single center. As a result of the laboratory test, the safety was evaluated by collecting vital signs of volunteers. Twelve subjects were assigned by serial number according to the registration order. For safety evaluation, blood samples were collected and vital signs were checked four times throughout the test period, including screening, pre-administration, post-administration (after 48 hours) and post-administration (after 7 days). The difference in variables was summarized as the mean±standard deviation. The normality was performed using Kolmogorov-Smirnov and Shapiro-Wilk test. If normality is satisfied, a paired t-test is applied. Otherwise, the Wilcoxon sign rank test, which is a nonparametric method, is applied. The significance was p<0.05. The incidence of all side effects is expressed as a percentage. Results In the case of red blood cell, hemoglobin, and hematocrit values, the result of normality test of variables for the difference value before and after administration is significant level p<0.05. However, all laboratory test values before and after administration did not deviate from the normal range. Also the deviations in the normal range could not be seen as significance related to this clinical trial. And no side effects related to clinical trial drugs were observed. Conclusions The soft extract of palmul-tang was considered safe for healthy male volunteers.

• 대한물리의학회지
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• 제9권4호
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• pp.407-413
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• 2014

PURPOSE: We investigated the influence of heel insole and visual control on body sway index with high-heeled shoes. METHODS: The subjects of this study were 61 healthy students. None of the participants had any orthopedic or neurologic alterations. C90 area, C90 angle, trace length, sway average velocity were measured using a force plate by BT4. The variables were measured both with insole and without insole when wearing high-heeled shoes under the conditions of eyes open and eyes closed. The collected data were analyzed using the Kolmogorov-Smirnov test and paired t-test. RESULTS: When wearing high-heeled shoes with insole under the conditions of eyes open, trace length, C90 area, velocity were significantly more decreased than without insole (p<.01). When wearing high-heeled shoes with insole under the conditions of eyes closed, only C90 area was significantly more decreased than without insole (p<.05). When wearing high-heeled shoes with insole under the conditions of eyes open, trace length, C90 area, velocity were significantly more decreased than under the conditions of eyes closed (p<.01). CONCLUSION: The present study demonstrates that the use of high-heeled shoes with insole supported from heel to midfoot more increased static balance than without insole under the conditions of eyes open.

• 한국도로학회논문집
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• 제19권4호
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• pp.9-18
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• 2017

PURPOSES : This study evaluates the reasonableness of the recommended amount of deicing chemicals based on historical data for snow removal. The result can be used to aid decision-making for the reservation of cost-effective de-icing chemicals. METHODS : First, the recommended amount of de-icing chemical to use and historical usage data were evaluated to identify specific usage characteristics for each region. Road maintenance length and snow-removal working days were analyzed over the past five winter seasons. Next, differences in the recommended amount of chemical to use and actual use were compared using the Kolmogorov-Smirnov test. Last, the two types of data were analyzed using a chi-square test to verify if the two distributions of variation pattern are statistically significant. We found that there are significant differences between the data from each region during the past five winter seasons. RESULTS : The results showed that the equation for calculating the amount of de-icing chemical to use appears to be revised. CONCLUSIONS : The results imply that the equation for calculating the amount of de-icing chemical to apply as a national standard is very important when the public agency makes decisions related to snow-removal.

• 한국농공학회지
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• 제38권4호
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• pp.110-124
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• 1996

This study was conducted to simulate long seres of synthetic monthly flows by multi-season first order Markov model with selection of best fitting frequency distribution, harmonic synthetic and harmonic regression models and to make a comparison of statistical parameters between observes and synthetic flows of five watersheds in Geum river system. The results obtained through this study can be summarized as follow. 1. Both gamma and two parameter lognormal distributions were found to be suitable ones for monthly flows in all watersheds by Kolmogorov-Smirnov test. 2. It was found that arithmetic mean values of synthetic monthly flows simulated by multi-season first order Markov model with gamma distribution are much closer to the results of the observed data in comparison with those of the other models in the applied watersheds. 3. The coefficients of variation, index of fluctuation for monthly flows simulated by multi-season first order Markov model with gamma distribution are appeared closer to those of the observed data in comparison with those of the other models in Geum river system. 4. Synthetic monthly flows were simulated over 100 years by multi-season first order Markov model with gamma distribution which is acknowledged as a suitable simulation modal in this study.

• The Journal of Advanced Prosthodontics
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• 제9권1호
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• pp.52-56
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• 2017

PURPOSE. Considering the importance of metal-ceramic bond, the present study aimed to compare the bond strength of ceramics to cobalt-chrome (Co-Cr) alloys made by casting and selective laser melting (SLM). MATERIALS AND METHODS. In this in-vitro experimental study, two sample groups were prepared, with one group comprising of 10 Co-Cr metal frameworks fabricated by SLM method and the other of 10 Co-Cr metal frameworks fabricated by lost wax cast method with the dimensions of $0.5{\times}3{\times}25\;mm$ (following ISO standard 9693). Porcelain with the thickness of 1.1 mm was applied on a $3{\times}8-mm$ central rectangular area of each sample. Afterwards, bond strengths of the samples were assessed with a Universal Testing Machine. Statistical analysis was performed with Kolmogorov-Smirnov test and T-test. RESULTS. Bond strength in the conventionally cast group equaled $74.94{\times}16.06\;MPa$, while in SLM group, it equaled $69.02{\times}5.77\;MPa$. The difference was not statistically significant ($P{\leq}.05$). CONCLUSION. The results indicated that the bond strengths between ceramic and Co-Cr alloys made by casting and SLM methods were not statistically different.

• 한국농공학회논문집
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• 제48권5호
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• pp.17-27
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• 2006

The objective of this study is to induce the design floods by the methodology of L-moment including test of homogeneity, independence and outlier of the data of annual maximum flood flows for 12 water level gaging stations of South Korea. To select appropriate distribution of the data for annual maximum flood flows, the distributions of Wakeby and Kappa are applied and the appropriateness is judged by Kolmogorov-smirnov (K-S) test. The parameters of selected Wakeby and Kappa distributions are calculated by the method of L-moment and the design floods are induced. Through the comparative analysis using the relative root mean square errors (RRMSE) and relative absolute errors (RAE) of design floods, the result shows that the design floods by Wakeby distribution are closer to the observed data than those obtained by the Kappa distribution.