• Advances in concrete construction
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• 제3권3호
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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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• 제24권6호
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• pp.1349-1357
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• 2013

임상시험에서 적당한 크기의 표본 수 결정은 통계적으로 유의한 연구결과의 도출과 연구수행의 효율적인 비용을 산출하기 위해서 중요한 사항 중의 하나이다. 기존의 비열등성 시험에서 표본 수 계산방법에는 t 검정법을 이용한 모수적 방법이 있고, Wilcoxon 순위합 검정을 이용하여 Wang 등 (2003)이 제안한 표본 수 계산방법을 Kim과 Kim (2007)이 비열등성 시험에 확장시켜 적용하여 제시한 비모수적 방법이 있다. 본 논문에서는 Orban과 Wolfe (1982)가 제안한 선형위치통계량의 검정법에 Kim (1994)이 계산한 검정력의 결과를 이용한 표본 수 계산 방법을 제안하고, 그에 따른 표본 수 계산결과를 기존에 제시된 표본 수 계산 결과와 비교하였다. 그 결과 기존의 방법들보다 본 논문에서 제안하는 방법으로 계산한 경우의 표본 수가 가장 작게 나왔다. 따라서 모집단에 대해서 구체적인 분포함수를 가정하기 힘든 경우 모수적 방법을 이용하게 되면 검정력이 떨어지거나 유의수준을 제어하지 못하는 문제점을 보완하고, 모수적 방법에 비해 표본 수가 크게 나와 시간이나 비용 면에서 효율적이지 않았던 Wilcoxon 순위합 검정을 이용한 방법의 단점을 보완할 수 있는 방법으로 본 논문에서 제시한 위치 (placement)를 이용한 표본 수 계산이 이용될 수 있다.

• 환경영향평가
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• 제6권1호
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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.

• 여성건강간호학회지
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• 제11권3호
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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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• 제18권2호
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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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• 제24권2호
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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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• 제20권4호
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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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• 제24권6호
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• pp.1241-1251
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• 2013

이 논문의 연구목적은 운동형태에 따라 중년여성의 신체구성과 혈중지질에 미치는 영향을 규명하기 위한 것이다. 연구대상은 40 50대 중년여성으로 유산소운동집단 8명, 복합트레이닝집단 8명 두 그룹으로 나누었으며, 12주간의 운동프로그램을 실시하였다. 운동강도는 주4회, 1회 70~90분, HRmax 60%~75%, 1RM 60%~80%로 점진적으로 증가시켰다. 자료처리는 Windows 용 SPSS ver. 21.0 통계 프로그램을 사용하여 평균과 표준편차 등을 산출하고, 비모수통계분석 방법인 윌콕슨 부호순위검정과 윌콕슨 순위합검정을 통해 그룹별 사전-사후 평균차와 변화량에 대한 그룹간 차이를 검정하였다. 연구결과를 살펴보면, 먼저 각 집단별 사전-사후 평균차에서는 복합운동 집단의 BMI, 체지방량, 그리고 중성지방에서만 통계적으로 유의한 차이가 나타났다. 또한 변인별 사전-사후 변화량에 대한 두 집단간의 차이 검정에서는 체지방량에서만 통계적으로 유의한 차이가 나타났다. 부가적으로 통계적 유의성은 검증되지 않았지만 각 별인별 사전-사후 평균 변화에 대한 기술통계를 살펴보면 복합운동이 유산소운동에 비해 상대적으로 더 효과적일 수 있다는 것을 알 수 있다.

• Child Health Nursing Research
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• 제18권1호
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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.

• 성인간호학회지
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• 제20권3호
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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.