• Wind and Structures
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• v.31 no.5
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• pp.419-430
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• 2020

Weibull distribution is a conspicuous distribution known for its accuracy and its usage for wind energy analysis. The two and three parameter Weibull distributions are adopted in this study to fit wind speed data. The daily mean wind speed data of Ennore, Tamil Nadu, India has been used to validate the procedure. The parameters are estimated using maximum likelihood method, least square method and moment method. Four statistical tests namely Root mean square error, R2 test, Kolmogorov-Smirnov test and Anderson-Darling test are employed to inspect the fitness of Weibull probability density functions. The value of shape factor, scale factor, wind speed and wind power are determined at a height of 100m using extrapolation of numerical equations. Also, the value of capacity factor is calculated mathematically. This study provides a way to evaluate feasible locations for wind energy assessment, which can be used at any windy site throughout the world.

• Journal of the Korean Data and Information Science Society
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• v.11 no.1
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• pp.83-90
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• 2000

The chi-squared test statistic is usually employed for testing independence of two categorical variables in a two-way contingency table. It is well known that, under independence, the test statistic has an asymptotic chi-squared distribution under multinomial or product-multinomial models. For the case where both margins fixed, the sampling model of the contingency table is a multiple hypergeometric distribution and the chi-squared test statistic follows the same limiting distribution. In this paper, we study the difference between the small sample and large sample distributions of the chi-squared test statistic for the case with fixed margins. For a few small sample cases, the exact small sample distribution of the test statistic is directly computed. For a few large sample sizes, the small sample distribution of the statistic is generated via a Monte Carlo algorithm, and then is compared with the large sample distribution via chi-squared probability plots and Kolmogorov-Smirnov tests.

• Research in Community and Public Health Nursing
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• v.19 no.4
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• pp.696-703
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• 2008

Purpose: To Perform a randomized comparative study investigating the effects of Pelvic Floor Muscle Exercise(PME) and Magnetic Stimulation Therapy(MST) and to identified the problems in each of PME & MST Method: Forty-nine patients with mild stress incontinence were randomly assigned to either of two treatment groups (24 patients in the PME group and 25 in the MST group). The PME group had a video exercising program for 40 times every day during 6 weeks. The MST group was treated with BioCon-2000TM, 2times/ week for six weeks. Pre-test and post-test were performed by Prineometer, 1-hour pad test. and Jackson's BFLUTS questionnaire of Jackson. Collected data were analysed using SAS 9.1 by frequency, Kolmogorov-Smirnov Z. Chi Square-test, t-test, Fisher Exact probability test, Paired t-test, and Wilcoxon's rank sum test. Results: In comparison between before and after PME and MST, statistically significant difference was observed in maximal vaginal pressure, duration of vaginal contraction, amount of urine, and symptom of urination. In the comparison of the effectiveness between PME & MST, only the maximal of vaginal pressure (Z=2.58, p= .010) was significantly different. Conclusion: The factor more effective in the MST group than in the PME group was high compliance.

• 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.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.737-745
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• 2017

The aim of this study was to develop a community based participatory obesity control program and measure the effects of the program on obesity, exercise habit, eating habit and life habits among obese elementary school children. The community based participatory obesity control program was provided for the experimental group of $4^{th}$ grade elementary school students for 10 weeks. The program included obesity related health educations and counseling once a week, jump rope classes twice a week and folk game classes held once a week. Method: There were 24 students with obesity in the experimental and 27 in the control groups. The collected data were analyzed by the Kolmogorov-Smirnov test, ${\chi}^2$-test, independent t-test and repeated measure ANOVA. Results: After 10weeks of participation in the program, the experimental group showed significantly lower Body Mass Index (p<.001) and waist hip ratio (p=.036), significantly higher exercise habit (p=.004), eating habit (p=.003) and life habit (p=.001) than those in the control group. Conclusion: This study provides evidence that community based participatory obesity management program is effective nursing intervention for managing child obesity.

• Research in Community and Public Health Nursing
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• v.21 no.2
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• pp.252-262
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• 2010

Purpose: Designed to examine the effects of aerobic exercise therapy on elders' physical functions. Methods: Selected from an elderly welfare center in an agricultural district located in N City. Thirty seven elders were selected in the experimental group and 38 in the control group, and all the subjects aged over 65. Collected data were statistically analyzed by SPSS/PC 12.0 Win. Detailed data analysis methods were Chi-square, Fisher's exact test, Kolmogorov-Smirnov test, t-test, Mann-Whitney u-test, paired t-test, and Wilcoxon's rank sum test. Results: The first hypothesis "The experimental group who had the aerobic exercise therapy will have greater development in lower leg muscular strength compared to the control group" was supported (t=8.95, p<.001). The second hypothesis "Aerobic exercise therapy participants will show greater development in lower leg endurance" was supported (t=6.12, p<.001). The third hypothesis "Aerobic exercise therapy participants will show greater development in flexibility" was supported (U=49.00, p<.001). The forth hypothesis "Aerobic exercise therapy participants will show greater development in balance" was supported (U=322.00, p<.001). Conclusion: The aerobic exercise therapy showed positive effects on physical functions of the elderly in a rural area.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.225-228
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• 2002

This research seeks to derive the design rainfalls through the L-moment with the test of homogeneity, independence and outlier of data on annual maximum daily rainfall in 38 Korean rainfall stations. To select the fit appropriate distribution of annual maximum daily rainfall data according to rainfall stations, applied were Generalized Extreme Value (GEV), Generalized Logistic (GLO) and Generalized Pareto (GPA) probability distributions were applied. and their aptness was judged Dusing an L-moment ratio diagram and the Kolmogorov-Smirnov (K-S) test, the aptitude was judged of applied distributions such as GEV, GLO and GPA. The GEV and GLO distributions were selected as the appropriate distributions. Their parameters were estimated Targetingfrom the observed and simulated annual maximum daily rainfalls and using Monte Carlo techniques, the parameters of GEV and GLO selected as suitable distributions were estimated and. dDesign rainfallss were then derived, using the L-moment. Appropriate design rainfalls were suggested by doing a comparative analysis of design rainfall from the GEV and GLO distributions according to rainfall stations.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.595-598
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• 2004

This research seeks to derive the design rainfalls through the L-moment with the test of homogeneity, independence and outlier of data on annual maximum daily rainfall at 38 rainfall stations in Korea. To select the appropriate distribution of annual maximum daily rainfall data by the rainfall stations, Generalized Extreme Value (GEV), Generalized Logistic (GLO), Generalized Pareto (GPA), Generalized Normal (GNO) and Pearson Type 3 (PT3) probability distributions were applied and their aptness were judged using an L-moment ratio diagram and the Kolmogorov-Smirnov (K-S) test. Parameters of appropriate distributions were estimated from the observed and simulated annual maximum daily rainfall using Monte Carlo techniques. Design rainfalls were finally derived by GEV distribution, which was proved to be more appropriate than the other distributions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2A
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• pp.196-201
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• 2010

Measurement of Quality of Service (QoS) parameters and its statistical analysis becomes a key issue for Mobile WiMAX service providers to manage the converged network efficiently and to support end-to-end QoS. In this paper, we investigate the population distribution of end-to-end one-way delay which is the most important QoS parameter in Mobile WiMAX networks. The samples are analyzed with Chi-Square Goodness-of-Fit test, Kolmogorov-Smirnov (K-S), and Anderson-Darling (A-D) test to verify the distribution of parent population. The relation with confidence level and the minimum number of sample size is also performed for logistic distribution. The statistical analysis is a promising approach for measuring the performance Mobile WiMAX networks.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.6
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• pp.49-60
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• 2002

This study was conducted to estimate the design flood by the determination of best fitting order of LH-moments of the annual maximum series at six and nine watersheds in Korea and Australia, respectively. Adequacy for flood flow data was confirmed by the tests of independence, homogeneity, and outliers. Gumbel (GUM), Generalized Extreme Value (GEV), Generalized Pareto (GPA), and Generalized Logistic (GLO) distributions were applied to get the best fitting frequency distribution for flood flow data. Theoretical bases of L, L1, L2, L3 and L4-moments were derived to estimate the parameters of 4 distributions. L, L1, L2, L3 and L4-moment ratio diagrams (LH-moments ratio diagram) were developed in this study. GEV distribution for the flood flow data of the applied watersheds was confirmed as the best one among others by the LH-moments ratio diagram and Kolmogorov-Smirnov test. Best fitting order of LH-moments will be derived by the confidence analysis of estimated design flood in the second report of this study.