• Title/Summary/Keyword: Kolmogorov test

Search Result 228, Processing Time 0.025 seconds

Extended Slip-Weakening Model and Inference of Rupture Velocity (Slip-Weakening 모델의 확장과 단층 파열속도의 추정)

  • Choi, Hang;Yoon, Byung-Ick
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.24 no.5
    • /
    • pp.219-232
    • /
    • 2020
  • The slip-weakening model developed by Ohnaka and Yamashita is extended over the breakdown zone by equating the scaling relationships for the breakdown zone and the whole rupture area. For the extension, the study uses the relationship between rupture velocity and radiation efficiency, which was derived in the theory of linear elastic fracture mechanics, and the definition of fmax given in the specific barrier model proposed by Papageorgiou and Aki. The results clearly show that the extended scaling relationship is governed by the ratio of rupture velocity to S wave velocity, and the velocity ratio can be determined by the ratio of characteristic frequencies of a Fourier amplitude spectrum, which are corner frequency, fc, and source-controlled cut-off frequency, fmax, or vice versa. The derived relationship is tested by using the characteristic frequencies extracted from previous studies of more than 130 shallow crustal events (focal depth less than 25 km, MW 3.0~7.5) that occurred in Japan. Under the assumption of a dynamic similarity, the rupture velocity estimated from fmax/fc and the modified integral timescale give quite similar scale-dependence of the rupture area to that given by Kanamori and Anderson. Also, the results for large earthquakes show good agreement to the values from a kinematic inversion in previous studies. The test results also indicate the unavailability of the spectral self-similarity proposed by Aki because of the scale-dependent rupture velocity and the rupture velocity-dependent fmax/fc; however, the results do support the local similarity asserted by Ohnaka. It is also remarkable that the relationship between the rupture velocity and fmax/fc is quite similar to Kolmogorov's hypothesis on a similarity in the theory of isotropic turbulence.

Survey of the use of statistical methods in Journal of the Korean Association of Oral and Maxillofacial Surgeons

  • Choi, Yong-Geun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.44 no.1
    • /
    • pp.25-28
    • /
    • 2018
  • Objectives: This study aimed to describe recent patterns in the types of statistical test used in original articles that were published in Journal of the Korean Association of Oral and Maxillofacial Surgeons. Materials and Methods: Thirty-six original articles published in the Journal in 2015 and 2016 were ascertained. The type of statistical test was identified by one researcher. Descriptive statistics, such as frequency, rank, and proportion, were calculated. Graphical statistics, such as a histogram, were constructed to reveal the overall utilization pattern of statistical test types. Results: Twenty-two types of statistical test were used. Statistical test type was not reported in four original articles and classified as unclear in 5%. The four most frequently used statistical tests constituted 47% of the total tests and these were the chi-square test, Student's t-test, Fisher's exact test, and Mann-Whitney test in descending order. Regression models, such as the Cox proportional hazard model and multiple logistic regression to adjust for potential confounding variables, were used in only 6% of the studies. Normality tests, including the Kolmogorov-Smirnov test, Levene test, Shapiro-Wilk test, and $Scheff{\acute{e}}^{\prime}s$ test, were used diversely but in only 10% of the studies. Conclusion: A total of 22 statistical tests were identified, with four tests occupying almost half of the results. Adoption of a nonparametric test is recommended when the status of normality is vague. Adjustment for confounding variables should be pursued using a multiple regression model when the number of potential confounding variables is numerous.

The Effects of Structured Preoperative Instruction on Anxiety and Self-care Compliance in Patients with Cataract Surgery (구조화된 수술 전 교육이 백내장 수술 환자의 불안과 자가간호 수행에 미치는 효과)

  • Choi, Mi Jung;Park, Jeong Sook
    • Korean Journal of Adult Nursing
    • /
    • v.25 no.4
    • /
    • pp.473-482
    • /
    • 2013
  • Purpose: The purpose of this study was to investigate the effects of a structured preoperative instruction upon anxiety and postoperative self-care compliance. Methods: A randomized control group pre-post design was used. Sixty subjects undergoing cataract surgery were randomly assigned to one of two groups. The instruction consisted of cataract surgery procedure, sensory information, deep breathing, use of eye drop, and post op self-care regimen and was provided to the experimental group with control group receiving an usual treatment. State anxiety NRS, pulse, BP, and self-care compliance scale developed by Cho & Rho were used. Data were collected at two time periods: on the day of surgery in the clinic and prior to anesthesia in the operating room. The postoperative self-care compliance scores were measured at their second visits to the hospital after surgery. Data were analyzed using Kolmogorov Smirnov test, t-test, and Mann-Whitney U test. Results: There were significant differences between the two groups in the postoperative state anxiety (t=-3.57, p=.001) and the postoperative self-care compliance score (t=3.92, p<.001). There were no significant difference between the two groups in the postoperative blood pressure and pulse rate. Conclusion: The results of this study suggest that the structured preoperative instruction could be a nursing intervention for cataract surgery patients.

Effects of an Action Learning based Creative Problem-Solving Course for Nursing Students (액션러닝 교수설계에 의한 창의적 문제해결 교과의 학습성과)

  • Jang, Keum Seong;Kim, Nam Young;Park, Hyunyoung
    • Journal of Korean Academy of Nursing Administration
    • /
    • v.20 no.5
    • /
    • pp.587-598
    • /
    • 2014
  • Purpose:This study was conducted to identify the effects of an action learning based creative problem-solving (CPS) course on problem solving, creativity and team-member exchange in nursing students. Methods: A quasi-experimental study applying a non-equivalent control group pre-post design was employed. Sophomore nursing students (32 in the experimental group and 33 in the control group) were recruited from a university in G-city, Korea. Problem solving, creativity and team-member exchange were measured for the pretest and posttest using self-report questionnaires. Kolmogorov-Smirnov test, Chi-square, Fisher's exact test, t-test, and ANCOVA with SPSS/Win 20.0 program were used to analyze the data. Results: The scores for problem solving, creativity and team-member exchange in the experimental group were significantly higher than those of the control group. Conclusion: Results of this study indicate that an action learning based CPS course is an effective teaching method to improve nursing students' competencies. In the future longitudinal studies are needed to assess the long term effects of the course.

The Effects of Exercise in the Frail Elderly (재가 허약노인을 위한 운동 프로그램 연구)

  • Park, Young-Im;Lee, Kang-Yi;Kim, Tae-Im;Jeon, Moung-Hee;Kim, Dong-Oak;Kim, Ji-Hyun
    • Research in Community and Public Health Nursing
    • /
    • v.23 no.1
    • /
    • pp.91-101
    • /
    • 2012
  • Purpose: This study was conducted to examine the effects of exercise on physiological, physical and psychological functions of the frail elderly. Methods: The research design was a nonequivalent control group pretest-posttest design. Data were collected from September 9 to October 10, 2009. The subjects were 56 frail elders who agreed to participate in this study and each subject was randomly assigned to either the experimental group (n=28) or the control group (n=28). The exercise program was provided to each subject in the experimental group twice in a week for 6 weeks. Data were analyzed with frequency, ${\chi}^2$-test, Kolmogorov-Smirnor test and independent t-test using SPSS/WIN 12.0. Results: There was a significant improvement in psychological functions in the experimental group compared to the control group (t=1.726, p=.045). Conclusion: The exercise program showed the effects to improve the psychological functions of the frail elderly with chronic disease. In recommendation, this exercise program could be utilized as a health promoting program for the frail elderly.

The Impact of Horizontal Mergers on the Performance of the Jordanian Banking Sector

  • AL-HROOT, Yusuf Ali;AL-QUDAH, Laith Akram;ALKHARABSHA, Faris Irsheid
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.7 no.7
    • /
    • pp.49-58
    • /
    • 2020
  • This paper examines the impact of mergers on the financial performance of the Jordanian banking sector. This paper applies the financial approaches in analysing the effects of mergers on Jordanian banks' performance for two the periods: four years pre-merger and four years' post-merger for the period from 2001 to 2009. The sample of the study solely contains the case of the merger of the Jordan Ahli Bank (AHLI bank) with Philadelphia Bank in 2005. Data are tested for normality using the Shapiro-Wilk Test and Kolmogorov Smirnov test. The financial ratios and a statistical technique as a Mann-Whitney U test were used to assess the significant differences in the financial performance of the selected banks pre- and post-merger by investigating the performance-related financial ratio groups that are expressed by leverage, liquidity, efficiency, and cash flow ratio. The results show that there is an insignificant improvement in the ratios of AHLI bank in the period after the merger, except for the superior result provided by this study indicating that the leverage ratios improved significantly. The reason for the insignificant improvement in financial ratios may be that the post-merger period corresponds to the period of the global financial crisis that began in 2007.

The Effects of Health Counseling Programs by Occupational Health Nurses on the Unemployed Visiting the Employment Welfare Plus Center (고용복지플러스센터 이용 구직자를 대상으로 산업간호사가 제공한 건강상담 프로그램의 효과)

  • Jung, Hye-Sun;Jang, Insun
    • Korean Journal of Occupational Health Nursing
    • /
    • v.25 no.3
    • /
    • pp.188-198
    • /
    • 2016
  • Purpose: The present study was conducted to examine the effects of a health counseling program by occupational health nurses on the unemployed visiting the Employment Welfare Plus Center. Methods: The one-group pretest-posttest design was used. The study presented a secondary analysis of the data collected in a health counseling program run by occupational health nurses for the unemployed visiting the Employment Welfare Plus Center. Kolmogorov-Smirnov, Shapiro-Wilk test, ${\chi}^2$ test and Wilcoxon signed rank test were used to analyze 158 data collected between October 5, 2015 and January 5, 2016. Results: After the intervention, the participants showed a significant decrease in the level of stress index (uBioMacpa), stress (discomfort), musculoskeletal pain and depression. In addition, the participants showed a significant increase in self-rated general health, exercise and regular eating behavior. Conclusion: The health counseling program offered by occupational health nurses is an effective intervention to improve the physical and mental health of the unemployed individuals visiting the Employment Welfare Plus Center.

Effects of therapeutic horse-riding program on the walking ability of students with intellectual disabilities

  • Kang, Ok-Deuk
    • Journal of Animal Science and Technology
    • /
    • v.63 no.2
    • /
    • pp.440-452
    • /
    • 2021
  • The purpose of this study was to determine if an 8-week therapeutic riding (TR) program was effective in improving the walking ability of students with intellectual disabilities. Thirteen students diagnosed with intellectual disabilities participated in the TR program. TR sessions were conducted twice a week (30 min per session), with a total of 16 rides taking place over an 8-week period. A gait measurement analyzer was used to measure progress based on a turn test (6-m walking and turning test), walk test (10-m walking), and timed up and go (TUG) test. Measurements were made three times: before horse-riding (P0), after 4 weeks (8 rides) of horse-riding (P1), and after 8 weeks (16 rides) of horse-riding (P2). Data analysis was conducted using SPSS software (ver. 22.0). Descriptive statistics were generated on the general characteristics of the subjects, and the Kolmogorov-Smirnov test was used to verify the normality of the data. Because of the lack of normality, the data were analyzed using a nonparametric method and the significance level was set to 0.05. Measurements of the duration of the forward gait cycle (s) in the turn test and the forward gait speed (m/s) in the walk test indicated improved walking ability after the TR program (p < 0.001); the stride length (% height) also increased significantly (p < 0.05). The walk test revealed a significant effect of the program on the duration of the forward gait cycle (p < 0.05), while there were significant improvements on the left and right of the elaborated strides (p < 0.001). No significant improvement in TUG test performance was observed after the TR program. In this study, an 8-week TR program had positive results on gait. Therefore, further research is merited, where TR programs are likely to improve the walking ability of individuals with intellectual disabilities.

Urban Area Building Reconstruction Using High Resolution SAR Image (고해상도 SAR 영상을 이용한 도심지 건물 재구성)

  • Kang, Ah-Reum;Lee, Seung-Kuk;Kim, Sang-Wan
    • Korean Journal of Remote Sensing
    • /
    • v.29 no.4
    • /
    • pp.361-373
    • /
    • 2013
  • The monitoring of urban area, target detection and building reconstruction have been actively studied and investigated since high resolution X-band SAR images could be acquired by airborne and/or satellite SAR systems. This paper describes an efficient approach to reconstruct artificial structures (e.g. apartment, building and house) in urban area using high resolution X-band SAR images. Building footprint was first extracted from 1:25,000 digital topographic map and then a corner line of building was detected by an automatic detecting algorithm. With SAR amplitude images, an initial building height was calculated by the length of layover estimated using KS-test (Kolmogorov-Smirnov test) from the corner line. The interferometric SAR phases were simulated depending on SAR geometry and changable building heights ranging from -10 m to +10 m of the initial building height. With an interferogram from real SAR data set, the simulation results were compared using the method of the phase consistency. One of results can be finally defined as the reconstructed building height. The developed algorithm was applied to repeat-pass TerraSAR-X spotlight mode data set over an apartment complex in Daejeon city, Korea. The final building heights were validated against reference heights extracted from LiDAR DSM, with an RMSE (Root Mean Square Error) of about 1~2m.

A Consideration on Intraspecific Competition with Particular Reference to Basal Area-class Structure of Even-aged Coniferous Monocultures (침엽수 동령 인공림내 개목들의 저적면적빈도분포에 의거한 종내경쟁에 대한 고찰)

  • 오계칠
    • Journal of Plant Biology
    • /
    • v.24 no.1
    • /
    • pp.47-57
    • /
    • 1981
  • Girth at breast height was measured to test skewness ($g_1$) and kurtosis ($g_2$) of frequency distribution of the basal area in terms of t-test and Kolmogorov-Smirnov test for a total of forty six monocultures within Sudong and Kwhangnung area in central part of Korean peninsula in 1979 and 1980. The monocultures are about 10 to 50 years old, and four kinds: Pinus koraiensis, Larix kaempferi, Abies holophylla and Pinus rigida. Most of the sample sizes per site were ranged 70 to 110 excluding 4 sites. The number of classes interval was based on Sturges rule for each monoculture and was ranged from 5 to 10. In Sudong the range of age(yr) and basal area (($cm^2$)/tree) of the monocultures were from 10 to 20 and from 27.60 to 383. for Kwhangnung they were from 15 to 47 and mostly 102.15 to 619.14, respectively. All 43 monocultures except 1 showed +$g_1$, which ranged from 0.3 to 2.2 except six sites. Of the total 46 sites, 23 sites showed significant +$g_1$ which includes about 10 year-old monoculture. The number of classes interval with significant positive skewness ranged from 6 to 9. The data suggest that intraspecific competition in terms of stand structure seems to appear from about 10 year-old monocultures, and it may even last to about 50 year-old one. Around 24 monocultures showed nonsignificant -$g_2$ except one. Most -$g_2$ ranged from -0.12 to -0.83. Around 20 monocltures showed positive $g_2$ ranging from +0.13 to +3.841. Of the 22 +$g_1$, majority of 11 were very highly significant. Of all monocultures only 5 showed significant result from Kolmogorov-Smirnov test. Of the 4 species, Larix kaempferi seems to show density stress first then Abies holophylla, and Pinus koraiensis last. Data of this study indicate that adequate number of classes intervals and sample sizes for studying intraspecific competition in terms of basal area are 6 to 9 and 80 trees rather than 12 and 100 trees, respectively. It also suggests that most of the frequency distribution of basal area class are trimodal rather than bimodal under density stress. It is proposed that the leptokurtic distribution appears before normal distribution rather than direct change from platykurtic to normal distribution of basal area for selected stages in the development of stands.

  • PDF