• Title/Summary/Keyword: kolmogorov-smirnov test

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Importance of the Temporal Variability of Rainfall Statistics in Stochastic Rainfall Modeling (추계강우모형에서의 강우통계의 시간적 변동성 연구)

  • Kim, Dong-Kyun;Lee, Jin-Woo;Cho, Yong-Sik
    • 한국방재학회:학술대회논문집
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    • 2010.02a
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    • pp.51.2-51.2
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    • 2010
  • A novel approach of Poisson cluster stochastic rainfall generator was validated in its ability to reproduce important rainfall and watershed response characteristics at 104 locations of the United States. The suggested novel approach - The Hybrid Model(THM), as compared to the traditional ones, has an additional function to account for the year-to-year variability of rainfall statistics. The two-sample Kolmogorov-Smirnov test was used to see how well THM and traditional approach of Poisson cluster rainfall model reproduce the distribution of the following hydrologic variables: monthly maximum rainfall depths with 1, 3, 6, 12, and 24 hour duration, monthly maximum flow peaks at the virtual watersheds with Curve Number of 50, 60, 70, 80 and 90; and monthly runoff depths at the same virtual watersheds. In all of the testing variables, THM significantly outperformed the traditional approach. This result indicates that the year-to-year variability of rainfall statistics contains important information about the characteristics of rainfall processes that were not considered by the conventional approach of Poisson cluster rainfall modeling and that further considering it in rainfall simulation will enhance the performance of the rainfall models.

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선박접안속도 실측값의 확률분포특성에 관한 연구

  • Lee, Sang-Won;Jo, Jang-Won;Jo, Ik-Sun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2018.11a
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    • pp.320-322
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    • 2018
  • 선박이 부두의 계류시설에 접촉할 때 발생하는 접안에너지는 해당선박의 접안속도에 가장 큰 영향을 받는다. 접안속도가 과다할 경우 부두에 접촉하는 사고로까지 이어질 수 있으므로 각각의 부두 특성에 맞는 적절한 접안속도를 설계하는 것이 중요하다. 선박접안속도의 경우, 일반적으로 대수정규분포를 따른다고 가정하고 있으나 국내에서는 이에 대한 검증이나 연구가 없어 해외의 사례를 바탕으로 설계접안 속도를 설정하고 있는 상황이다. 이에 본 연구에서는 부두의 선박접안속도를 설계하기 위한 통계학적인 접근으로 접안속도의 실측데이터를 토대로 그 빈도수를 히스토그램으로 표현하여 각각의 확률분포도와 비교 분석하고, 확률분포에 대한 검정법으로 K-S (Kolmogorov-Smirnov Test) 검정, A-D(Anderson-Darling) 검정, Q-Q(Quantile-Quantile) Plot 등을 이용하여 접안속도 분포에 적합한 확률분포도를 확인하였다. 분석 결과, 선박접안속도의 빈도분포는 일반적으로 알려진 대수정규분포 뿐만 아니라 Weibull 분포와 적합한 형태를 보이는 것을 알 수 있었다. 추가적으로 본 연구에서는 초과확률 개념에서의 접안속도의 예측치를 구하여 구해진 1/1000, 1/10000의 접안속도 예측치를 설계접안속도의 참고자료로 제안하고자 한다.

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Relationship between Gait, Static Balance, and Pelvic Inclination in Patients with Chronic Stroke

  • Choe, Yu-Won;Kim, Kyu-Ryeong;Kim, Myoung-Kwon
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.1
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    • pp.17-22
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    • 2021
  • PURPOSE: This study examined the correlations between gait, static balance, and pelvic inclination in patients with chronic stroke. METHODS: Twenty-two chronic stroke patients were included in this study. The subjects participated in gait, static balance, and pelvic inclination tests. In the gait measurement, the cadence and gait velocity were measured, and the average of three trials was calculated and recorded. The static balance was measured using a force platform. The data was captured for ten seconds, and five successful trials were recorded. Pelvic inclination in the sagittal plane was measured using a palpation meter. For data processing, a KolmogorovSmirnov test was used to determine the type of distribution for all variables. Pearson's correlation coefficient was used for correlation analysis. The correlations among the gait, static balance, and pelvic inclination was calculated. The level of significance was .05. RESULTS: Significant negative correlations were observed between the gait variables (cadence, velocity) and static balance variables (COP path length, COP average velocity, and 95% confidence ellipse area) (p < .05). On the other hand, there was no significant correlation between pelvic inclination and gait or between the pelvic inclination and static balance variables. CONCLUSION: Significant correlations were observed between the gait function and static balance. On the other hand, there were no significant correlations between the pelvic inclination and gait and static balance. These results suggest that the pelvic inclination is not an important consideration for increasing the gait function and static balance.

Safety of Palmultang Soft Extract after Single Oral Administration in Healthy Male Volunteers, Single Center Study (팔물탕연조엑스의 단회 경구 투여 안전성 평가에 관한 연구)

  • Yeong-jin Jeong;Su-Hak Kim;Ji-Sung Lim;Young-Dal Kwon
    • Journal of Korean Medicine Rehabilitation
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    • v.33 no.1
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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.

A simulation comparison on the analysing methods of Likert type data (모의실험에 의한 리커트형 설문분석 방법의 비교)

  • Kim, Hyun Chul;Choi, Seung Kyoung;Choi, Dong Ho
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.2
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    • pp.373-380
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    • 2016
  • Even though Likert type data is ordinal scale, many researchers who regard Likert type data as interval scale adapt as parametric methods. In this research, simulations have been used to find out a proper analysis of Likert type data. The locations and response distributions of five point Likert type data samples having diverse distribution have been evaluated. In estimating samples' locations, we considered parametric method and non-parametric method, which are t-test and Mann-Whitney test respectively. In addition, to test response distribution, we employed Chi-squared test and Kolmogorov-Smirnov test. In this study, we assessed the performance of the four aforementioned methods by comparing Type I error ratio and statistical power.

Derivation of Optimal Design Flood by L-Moments and LB-Moments ( I ) - On the method of L-Moments - (L-모멘트 및 LH-모멘트 기법에 의한 적정 설계홍수량의 유도( I ) - L-모멘트법을 중심으로 -)

  • 이순혁;박명근;맹승진;정연수;김동주;류경식
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.40 no.4
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    • pp.45-57
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    • 1998
  • This study was conducted to derive optimal design floods by Generalized Extreme Value (GEV) distribution for the annual maximum series at ten watersheds along Han, Nagdong, Geum, Yeongsan and Seomjin river systems. Adequacy for the analysis of flood data used in this study was established by the tests of Independence, Homogeneity, detection of Outliers. L-coefficient of variation, L-skewness and L-kurtosis were calculated by L-moment ratio respectively. Parameters were estimated by the Methods of Moments and L-Moments. Design floods obtained by Methods of Moments and L-Moments using different methods for plotting positions in GEV distribution were compared by the Relative Mean Errors(RME) and Relative Absolute Errors(RAE). The results were analyzed and summarized as follows. 1. Adequacy for the analysis of flood data was acknowledged by the tests of Independence, Homogeneity and detection of Outliers. 2. GEV distribution used in this study was found to be more suitable one than Pearson type 3 distribution by the goodness of fit test using Kolmogorov-Smirnov test and L-Moment ratios diagram in the applied watersheds. 3. Parameters for GEV distribution were estimated using Methods of Moments and L-Moments. 4. Design floods were calculated by Methods of Moments and L-Moments in GEV distribution. 5. It was found that design floods derived by the method of L-Moments using Weibull plotting position formula in GEV distribution are much closer to those of the observed data in comparison with those obtained by method of moments using different formulas for plotting positions from the viewpoint of Relative Mean Errors and Relative Absolute Errors.

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Red AGNs becoming normal AGNs

  • Kim, Dohyeong;Im, Myungshin;Glikman, E.;Woo, Jong-Hak;Urrutia, T.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.57.2-57.2
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    • 2014
  • Red active galactic nuclei (AGNs) are supposed to be transitional objects becoming normal AGNs in the galaxy evolution scenario. So far, ~200 red AGNs have been found by very red color in optical through NIR wavelength (e.g., r'-K >5 and J-K>1.3; Urrutia et al. 2009). Here, we compare nuclear activities of the red AGNs to those of normal AGNs to verify the evolutionary phase of the red AGNs. In order to study the nuclear activities of the red AGNs, we use broad emission lines of $P{\beta}$ ($1.28{\mu}m$) of which flux is less suppressed by a factor of 100 than the $H{\beta}$ line in the case of the red AGNs with a color excess of E(B-V)=2 mag. We use 16 red AGNs discovered in previous red AGN surveys by using SDSS, 2MASS, and FIRST (Glikman et al. 2007; Urrutia et al. 2009) at z ~0.7 for which $P{\beta}$ lines are redshifted to the sky window at ${\sim}2.2{\mu}m$. The mean Eddington ratio of the 16 red AGNs is 0.562, and that of the normal AGNs is 0.320, which indicates the red AGNs include more active black hole (BH) than the normal AGNs. To test how significantly the nuclear activities of the red AGNs and the normal AGNs are different, we perform a two-dimensional Kolmogorov-Smirnov test (K-S test) on their Eddington ratio distributions. The K-S test shows the maximum deviation between the cumulative distributions, D, is 0.48, and the probability of null hypothesis, p, is even less than 0.001. This result is consistent with a picture of that the red AGNs are in intermediate phase between the stage of merger-driven starburst galaxy and the normal AGN.

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An Effect of the Secondary Stroke Prevention Education Program on Self-care of Acute Ischemic Stroke Patients (뇌졸중 이차예방 교육프로그램이 급성기 허혈성 뇌졸중환자의 자가간호수행에 미치는 효과)

  • Kang, Sun Mi;Yeun, Eun Ja
    • Korean Journal of Adult Nursing
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    • v.17 no.4
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    • pp.646-655
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    • 2005
  • Purpose: This study was conducted to examine the effects of the secondary stroke prevention education program to inhibit the recurrence of the acute ischemic stroke patients, and to maintain and promote knowledge about stroke, self-efficacy and self-care. Method: This study was designed to take a quasi-experimental pre- and post-test with the nonequivalent control group. The experimental group consists of 20 patients and control group consists of 20 patients. The experimental group was applied the secondary stroke prevention education program. In order to verify the effects of the secondary stroke prevention education program, knowledge about stroke, self-efficacy and self-care scale were measured before the intervention and 4 weeks, 12 weeks after discharge. The tools for measuring knowledge about stroke, self-efficacy and self-care are developed by the researcher. The data was analyzed by SPSS win 10.0 program using $x^2-test$, Fisher's Exact Test, t-test, Kolmogorov-Smirnov Z, and Repeated Measures ANOVA. Result: There was a statistically significant difference in knowledge about stroke (F=4.021, p=.026), self-efficacy(F=6.096, p=.018), and self-care(F=8.026, p=.007) between the experimental and the control group after intervention. Conclusion: It is considered that the program can be used as an effective nursing intervention in clinical practice.

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A Study on the Evaluation of Probable Snowfall Depth in Korea (우리나라의 확률적설량 산정에 관한 연구)

  • Lee, Jae-Joon;Jung, Young-Hoon;Lee, Sang-Won
    • Journal of the Korean Society of Hazard Mitigation
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    • v.7 no.2 s.25
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    • pp.53-63
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    • 2007
  • This study is to evaluate the probable snowfall depth by the point frequency analysis and to draw the map of probable snowfall depth in Korea. The 14 probability distributions which has been widely used in hydrologic frequency analysis are applied to the annual maximum depth of snowfall data. The parameters of each probability distribution are estimated by method of moments, maximum likelihood method and method of probability weighted moments. The estimated parameters were checked by parameter validity conditions of each assumed probability distribution. Four tests that are $X^2-test$, Kolmogorov-Smirnov test, Cramer von Mises test and probability plot correlation coefficient test are used in this study to determine the goodness of fit of the distributions. Mostly the 2-parameter gamma distribution was determined as appropriate distribution for the annual maximum new snowfall depth. The probable snowfall depth were obtained from appropriate distribution for the selected return periods and the maps of probable snowfall depth were presented. It will be useful to specify the snowfall load for the design of agricultural facilities such as vinyl house and cattle shed.

Effects of an Educational Program of Pregnancy and Delivery on Pregnancy related Knowledge, Newborn Care Knowledge, and Postpartum Care Self-efficacy of Marriage Immigrant Women (결혼이주여성을 위한 임신/분만관리 교육프로그램이 임신관련지식, 신생아 양육지식 및 산후관리 자기효능감에 미치는 효과)

  • Kim, Eun-Hee;Lee, Eun-Joo;Kim, Mi-Jo;Park, Dong-Young;Lee, Sung-Hee
    • Journal of Korean Academy of Nursing
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    • v.40 no.1
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    • pp.78-87
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    • 2010
  • Purpose: This study was designed to evaluate the effects of an educational program on pregnancy and delivery including pregnancy related knowledge, newborn care knowledge, and postpartum care self-efficacy for married immigrant women. Methods: A nonequivalent control group quasi-experimental design was used. The educational program was developed by though an educational need assessment of married immigrant women and an expert opinion. The program was provided for 3 weeks, once a week for two hours. The data were analyzed with SPSS program using Kolmogorov-Smirnov, $X^2$-test, Fisher's exact test, and t-test. Results: The program significantly improved pregnancy related knowledge, newborn care knowledge, and postpartum care self-efficacy for the married immigrant women who participated in the program compared to the women who did not. Conclusion: The results indicate that the educational program has an affirmative effect on pregnancy related knowledge, knowledge of newborn care, and postpartum care self-efficacy in these women. It is suggested, therefore, that the educational program be used to every married immigrant woman at the public health centers or delivery clinics help them to adjust to the childbearing and childrearing experience and this will ultimately enhance the quality of family life of married immigrant women in Korea.