• Advances in concrete construction
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• v.3 no.3
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• pp.161-185
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• 2015

FRP confining is a widely used method for seismic retrofitting of concrete columns. Several studies investigated the stress-strain behavior of FRP confined concrete prisms with square and rectangular sections both experimentally and analytically. In some studies, the monotonic stress-strain behavior of confined concrete was investigated and compressive strength models were developed. To study the reliability of these models, thorough statistical tests are required. This paper aims to investigate the reliability of the presented models using statistical tests including t-test, wilcoxon rank sum test, wilcoxon signed rank test and sign test with a level of significance of 5%. Wilk Shapiro test was also employed to evaluate the normality of the data distribution. The results were compared for different cross section and confinement types. To see the accuracy of the models when there were no significant differences between the results, the coefficient of confidence was used.

• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1349-1357
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• 2013

In clinical research, sample size determination is one of the most important things. There are parametric method using t-test and non-parametric method suggested by Kim and Kim (2007) based on Wilcoxon's rank sum test for determining sample size in non-inferiority trials. In this paper, we propose sample size calculation method based on placements method suggested by Orban and Wolfe (1982) and using the power calculated by Kim (1994) in non-inferiority trials. We also compare proposed sample size with that using Kim and Kim (2007)'s formula and that of t-test for parametric methods. As the result, sample size calculated by proposed method based on placements is the smallest. Therefore, proposed method based on placements is better than parametric methods in case that it's hard to assume specific distribution function for population and also more efficient in terms of time and cost than method based on Wilcoxon's rank sum test.

• 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.

• Women's Health Nursing
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• v.11 no.3
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• pp.209-217
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• 2005

Purpose: This study was conducted to investigate the effects of foot reflexzone massage on state - anxiety and discomfort of ovarian cancer patients receiving chemotherapy. Method: A quasi experimental design with a non equivalent control group and non synchronized design was used. The experiment was conducted from October 1, 2003 to September 30, 2004. The subjects consisted of 40 patients admitted to C University Hospital. Twenty subjects were assigned to the experimental group and received foot reflexzone massage everyday for 3 days. The other 20 subjects were in the control group and received routine care. Foot reflexzone massage was done on both feet of the subjects for 30 minutes for 3 days using standard protocol. The 'State-Anxiety Inventory' developed by Spielberger was used to measure the degree of state-anxiety. Discomfort was assessed using the 'Symptom Distress Scale' of McCorkle and Young. Data was analyzed by a SAS program using t-test, Wilcoxon signed rank sum test and Wilcoxon rank sum test. Results: State-anxiety and discomfort of subjects receiving foot reflexzone massage were significantly lower than those of the control group. Conclusion: These findings indicate that foot reflexzone massage could be an effective nursing intervention for relieving state-anxiety and discomfort in ovarian cancer patients.

• Journal of the Korean Data and Information Science Society
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• v.18 no.2
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• pp.411-418
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• 2007

Sample size calculation is very important in clinical trials. In this paper, we propose sample size calculation method for non-inferiority trials using sample size calculation method suggested by Wang et al.(2003) based on Wilcoxon's rank sum test. Also, sample size comparison between parametric method and proposed method are presented.

• Educational Technology International
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• v.24 no.2
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• pp.169-202
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• 2023

This study aims to develop instructional design strategies included in educational programs that can effectively improve the educational data literacy of pre-service teachers. We used the design and development model proposed by Richey and Klein and investigated its internal and external validity. Internal validity assessment involved the input of five experts who evaluated the initial instructional strategies. We conducted an educational data literacy education program with 29 pre-service teachers from Korean colleges and graduate schools for external validity. The effectiveness of the program was verified by the Wilcoxon Rank Sum Test, which revealed a meaningful statistical difference between Wilcoxon Rank Sum Test post-scores after the four weeks of online classes. Therefore, this study developed instructional strategies followed by the steps of data-based decision-making: the final instructional strategies encompass 21 strategies, categorized for implementation before, during, and after classes, accompanied by 38 detailed guidelines. This approach bears notable significance as it encapsulates actionable and effective instructional strategies thoughtfully tailored to the unique circumstances and educational setting of the field, as well as the specific characteristics and requirements of the learners.

• Communications for Statistical Applications and Methods
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• v.20 no.4
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• pp.241-246
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• 2013

In this study, we propose a nonparametric simultaneous test procedure for the location translation and scale parameters. We consider the Wilcoxon rank sum test for the location translation parameter and the Mood test for the scale parameter with the quadratic and maximal types of combining functions. Then we derive the limiting null distributions of the combining functions. We illustrate our procedure with an example and compare efficiency by obtaining the empirical powers through a simulation study. Finally, we discuss some interesting features related to the nonparametric simultaneous tests.

• Journal of the Korean Data and Information Science Society
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• v.24 no.6
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• pp.1241-1251
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• 2013

The purpose of this study was to investigate and compare the effects of aerobic and complex exercise on body composition and blood lipids in the middle-aged women. Sixteen women whose ages ranged in 40 to 50 years were included in the sample of the study. The sample was divided into two groups: (a) aerobic exercise group (n = 8) and (b) combined exercise training group (n = 8). The aerobic exercise program consisted of bicycle ergometer, stepper, and treadmill, whereas; the combined exercise program was designed to improve muscular strength and aerobic capacity. Both programs took place 4 times a week for 12 weeks with the gradual increase of intensity (HRmax 60% 75% and 1 RM 60% 80%). Data were analyzed by nonparametric methods for pre-post within group mean differences (Wilcoxon signed rank test) and for between group mean differences (Wilcoxon rank sum test). Results indicated that there were statistically significant differences in BMI, body fat mass, and triglyceride within the sample of combined exercise; whereas, no significance existed in any variables within the aerobic exercise group. Results also revealed that statistical significance did exist in body fat mass between the combined and aerobic exercise group. These results implies that the combined exercise may be superior to aerobic only excercise for the body composition and blood lipid of the middle-aged women.

• Child Health Nursing Research
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• v.18 no.1
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• pp.1-8
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• 2012

Purpose: The purpose of this study was to identify the effects of an empowerment program on nicotine dependency, temptation, self-esteem, and depression for adolescents who smoke. Methods: The study design was a quasi-experimental study with a nonequivalent control group, pre-post design. The participants were 49 adolescents who smoked. Twenty-six adolescents were assigned to the experimental group and 23 to the control group. The intervention was conducted twice a week for 6 weeks. Chi-square test, t-test, paired-test, Wilcoxon rank sum test and Wilcoxon signed rank test were used to analyze the data. Results: After program, scores for self-esteem (t=5.560, p=.014), were significantly higher and scores for depression (t=-2.111, p=.040) were significantly lower for adolescents in the experimental group compared to adolescents in the control group. Conclusion: The finding indicate that the empowerment group training program was effective in improving self-esteem, and decreasing depression and could be considered as a positive program for smoking cessation for adolescents who smoke.

• Korean Journal of Adult Nursing
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• v.20 no.3
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• pp.418-430
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• 2008

Purpose: This study was to examine the effects of Seogeum therapy for middle-aged abdominal obese women. Methods: Seogeum therapy combined cupping, stepping on ion aluminum board, adhering to Seoam moxibustion and Seoam pellet. The subjects consisted of 30 middle-aged abdominal obese women between 40 and 59 years of age: fifteen were assigned to experimental group, fifteen to control group. The data collection and treatments were performed from June to October, 2007. The subjects of experimental group participated in Seogeum therapy for 5 times per week during 8 weeks. The data were analyzed with Chi-square test, Wilcoxon signed rank test and Wilcoxon rank-sum test with SPSS/Window 12.0 program. Results: Seogeum therapy experimental group showed significant difference in change of general obesity indexes(body weight, body fat amount, body fat ratio, BMI) than control group supporting hypothesis 1. Experimental group showed significant difference in change of abdominal obesity indexes(abdominal fat ratio, waist circumference, hip circumference) than control group supporting hypothesis 2. Conclusion: Obesity management of Seogeum therapy had a positive effect for middle-aged obese women. Therefore, it is concluded that the obesity management of Seogeum therapy can be applied as a nursing intervention to decrease the obesity for middle-aged women.