• Journal of the Korean Association of Geographic Information Studies
• /
• v.11 no.1
• /
• pp.155-166
• /
• 2008

The quantitative bivariate spatial pattern analysis was applied for the water quality and nutrients data of Masan Bay, and for this analysis Pearson's r as aspatial correlation measurement, Moran's I as spatial association measurement and L index as integration of aspatial and spatial measurement methods were used. To understand the aspatial and spatial characteristics implicated in L index, Pearson's r as well as Moran's I were classified into 3 types respectively, and Pearson's r and Moran's I were combined with 9 types, and also quantile of L index value was used for each of those 9 types. Finally, these types were defined as 5 groups having not overlapped L index range. According to the application result of L index groups, bivariate water quality and nutrients showed no aspatial correlation regardless of spatial association in February and July, but they showed aspatial correlation having clustered spatial pattern in May and November. The result of this study providing the guideline for the interpretation of aspatial correlation and spatial association using L index is expected to be helpful for the marine environment pattern analysis using quantitative index for further study.

• The Journal of Korean Society for Radiation Therapy
• /
• v.29 no.2
• /
• pp.65-73
• /
• 2017

Purpose: Machine Performance Check (MPC) is a self-checking software based on the Electronic Portal Imaging Device (EPID) to measure daily beam outputs without external installation. The purpose of this study is to verify the usefulness of MPC by comparing and correlating daily beam output of QA Beamchecker PLUS. Materials and Methods: Linear accelerator (Truebeam 2.5) was used to measure 10 energies which are composed of photon beams(6, 10, 15 MV and 6, 10 MV-FFF) and electron beams(6, 9, 12, 16 and 20 MeV). A total of 80 cycles of data was obtained by measuring beam output measurement before treatment over five months period. The Pearson correlation coefficient was used to evaluate the consistency of the beam output between the MPC and the QA Beamchecker PLUS. In this study, if the Pearson correlation coefficient is; (1) 0.8 or higher, the correlation is very strong (2) between 0.6 and 0.79, the correlation is strong (3) between 0.4 and 0.59, the correlation is moderate (4) between 0.2 and 0.39, the correlation is weak (5) lower than 0.2, the correlation is very weak. Results: Output variations observed between MPC and QA Beamchecker PLUS were within 2 % for photons and electrons. The beam outputs variations of MPC were $0.29{\pm}0.26%$ and $0.30{\pm}0.26%$ for photon and electron beams, respectively. QA Beamchecker PLUS beam outputs were $0.31{\pm}0.24%$ and $0.33{\pm}0.24%$ for photon and electron beams, respectively. The Pearson correlation coefficient between MPC and QA Beamchecker PLUS indicated that photon beams were very strong at 15 MV, and strong at 6 MV, 10 MV, 6 MV-FFF and 10 MV-FFF. For electron beams, the Pearson correlation coefficient were strong at 16 MeV and 20 MeV, moderate at 9 MeV and 12 MeV, and very weak at 6 MeV. Conclusion: MPC showed significantly strong correlation with QA Beamchecker PLUS when testing with photon beams and high-energy electron beams in the evaluation of daily beam output, but the correlation when testing with low-energy electron beams (6 MeV) appeared to be low. However, MPC and QA Beamchecker PLUS are considered to be suitable for checking daily beam output, as they performed within 2 % of beam output consistency during the observation. MPC which can perform faster than the conventional daily beam output measurement tool, is considered to be an effective method for users.

• Journal of Community Nutrition
• /
• v.6 no.1
• /
• pp.35-41
• /
• 2004

Cardiovascular disease has the highest mortality rate in South Korea. Previous studies have reported that serum cholesterol level relates to intake of dietary fat and cholesterol. Therefore, in this study we developed a semiquantitative food frequency questionnaire (FFQ) for Koreans with a high-risk of hypercholesterolemia and to validate the FFQ. Semiquantitative FFQ, which includes 160 food items, reflects intakes of energy, fat, saturated fatty acid (SFA), monounsaturated fatty acid (MUPA), polyunsaturated fatty acid (PUPA) and cholesterol. We chose food items from the previous study of our research group (Suh 1999) which reported a nutritional status of Korean adults with normocholesterolemia, borderline and hypercholesterolemia. To validate the FFQ, we compared the results of the FFQ with those of a 3-day food record using a paired t-test. In addition, we calculated Pearson's and Spearmen's correlation coefficients. Intakes assessed by the FFQ and a 3-day food record were classified into quartile and the degree of agreement was obtained. Fifty-five participants responded for the validation study by completing both the FFQ and a 3-day food record. Pearson's correlation coefficients between estimated intakes by respective methods for energy, fat, SF A, MUPA, PUPA and cholesterol were 0.32,0.41,0.37,0.41,0.37 and 0.21, respectively. Spearman's correlation coefficients of energy, fat, SF A, MUPA, PUPA, cholesterol were 0.31, 0.44, 0.39, 0.46, 0.46, and 0.37, respectively. Nutrient densities in 1000kcal were compared. Pearson's correlation coefficient of cholesterol density increased and other values were similar with original values. The average degree of agreement was 67％ that intakes of energy, fat, SF A, MUPA, PUPA and cholesterol assessed by the FFQ and 3-day food records were classified within the same and the adjacent quartile. On the average, 8％ were misclassified into the extreme opposite quartile. The average of weighted kappa was 0.46. In conclusion, the FFQ developed in this study is considered to be a reliable tool to assess nutrient intakes for Koreans with a risk of hypercholesterolemia because the FFQ reflects the intakes of energy, fat, SFA, MUFA, PUPA, and cholesterol.

• PNF and Movement
• /
• v.14 no.1
• /
• pp.53-57
• /
• 2016

Purpose: This study aimed to examine the correlation between the asymmetric ratio of occlusal force of the temporomandibular joint and the thickness of the middle scalene muscle. Methods: The study measured the occlusal force of the right and left temporomandibular joints in 30 subjects (12 males and 18 females). Pearson's correlation analysis was performed to examine the effect of occlusal force on the asymmetric ratio of the thickness of their middle scalene muscles by measuring the force using ultrasound after the break. Results: The correlation between the asymmetric ratio of occlusal force and muscle thickness is 0.41, according to Pearson's correlation coefficient. Therefore, the result shows a moderate correlation with the asymmetric ratio of the temporomandibular joint depending on differences in the thickness of the middle scalene muscle. Conclusion: Based on the above results, the asymmetric ratio of occlusal force was found to correlate with the thickness of the middle scalene muscle. Thus, therapeutic intervention is required for the middle scalene muscle in the case of temporomandibular joint disorder.

• Korean Journal of Health Education and Promotion
• /
• v.20 no.2
• /
• pp.197-216
• /
• 2003

This study has been done in order to examine elementary school pupil's knowledge and attitudes on sex. The subjects of the study were 1904 elementary school pupils in the 5th and 6th grade of three elementary schools in Kyonggi-do, Korea. A guide book for the teachers on sexual education published by the Ministry of Education and Human Resources has been used as the tool for the study. Data analysis has been performed by using SPSS Win(l0.0) with mean, standard deviation, t-test, F-test(ANOVA), and Pearson's Correlation. The results show that the human relationship area showed the highest, next were physical development, sexual culture and sexual ethics, and the last were sex health and sexual psychology. The Pearson's correlation between each area of knowledge and attitude on sex show a significant correlation statistically in the level of p＜.001 in all areas. When examined individually the highest correlation was demonstrated between physical development and sexual health and human relationship by r＝.573, while it demonstrated only r＝.265 the lowest between sexual ethics and physical development.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.11
• /
• pp.115-120
• /
• 2019

This study was undertaken to determine the correlation between β-amyloid, serum lipid levels, and cognitive function in the elderly with mild Alzheimer's dementia. The study was conducted in December 2018, enrolling 45 elderly people with mild Alzheimer's disease. Blood analysis measured the β-amyloid and serum lipid levels, and cognitive function was measured using MMSE-K. The correlation between β-amyloid, serum lipid levels and cognitive function was determined using Pearson's correlation analysis. A significantly negative correlation was observed between the β-amyloid level and cognitive function (p<0.05). Furthermore, serum lipid levels and cognitive function also revealed a significantly negative correlation between TC and LDL levels (p<0.05). These results indicate that increasing levels of β-amyloid, TC, and LDL augments a negative correlation that decreases the cognitive function, signifying that management of pathologic factors related to dementia is important for the prevention and improvement of cognitive function in dementia patients.

• Journal of Fashion Business
• /
• v.5 no.2
• /
• pp.117-127
• /
• 2001

This study identified self-image of the eldery wemen by relatied to body-satisfaction, self-image, shopping-orientatons. For study, a questionnaire was used a method of mearsurement and eldery women in seoul and kyunggi were selected as a sample. Data was processed by SPSS PC+ program and analyzed by using frequency, percentage, t-test, factor analysis and Pearson's correlation. As a result, the body-satisfaction of eldery women was very low, their pursuiting self-image was gracios, younger, noble. The self-image classified grace attraction factor, intelligence factor and activity factor. Relationship between body-satisfaction and self-images was significant to gracious attractive factor and active factor. The shopping-orientatons classified brand name disply factor, personality pride factor, pratical benefit factor, prudence factor, planning purchase factor. Shopping-orientatons and self-images were significant to Pearson's correlation. The aim of this study help fashion contractors and retailers to establish effective marketing strategies.

• Restorative Dentistry and Endodontics
• /
• v.49 no.2
• /
• pp.21.1-21.8
• /
• 2024

Objectives: This paper aims to serve as a useful guide for sample size determination for various correlation analyses that are based on effect sizes and confidence interval width. Materials and Methods: Sample size determinations are calculated for Pearson's correlation, Spearman's rank correlation, and Kendall's Tau-b correlation. Examples of sample size statements and their justification are also included. Results: Using the same effect sizes, there are differences between the sample size determination of the 3 statistical tests. Based on an empirical calculation, a minimum sample size of 149 is usually adequate for performing both parametric and non-parametric correlation analysis to determine at least a moderate to an excellent degree of correlation with acceptable confidence interval width. Conclusions: Determining data assumption(s) is one of the challenges to offering a valid technique to estimate the required sample size for correlation analyses. Sample size tables are provided and these will help researchers to estimate a minimum sample size requirement based on correlation analyses.

• Journal of Korean Medicine Rehabilitation
• /
• v.19 no.2
• /
• pp.251-260
• /
• 2009

Objectives : To investigate reliability and validity of Korean translation of Western Ontario and McMaster Universities(WOMAC) osteoarthritis index. Methods : The reliablity, construct validity of the Korean WOMAC Index in the patient of knee osteoarthritis was investigated. Test-retest reliability was quantified with pearson's correlation coefficient and intraclass correlation coefficient. Internal consistency was quantified with Cronbach's ${\alpha}$. and construct validity with pearson's correlation coefficient by correlating of the Visual Analog Scale(VAS). Results : Test-retest reliability of Korean WOMAC Index for pain was 0.76 to 0.95, stiffness was 0.89 to 0.94, and physical function was 0.71 to 0.95. Intraclass correlation coefficient for pain was 0.76 to 0.94, stiffness was 0.54 to 0.89, and physical function was 0.70 to 0.95. Internal consistency were 0.94 and 0.94 for the first and second time, respectively. Construct validity for pain was 0.79, for stiffness was 0.66, and physical function was 0.67. Conclusions : The Korean translation of Western Ontario and McMaster Universities(WOMAC) osteoarthritis index is reliable, valid assessment tool in knee osteoarthritis.

• Journal of Convergence for Information Technology
• /
• v.9 no.11
• /
• pp.38-46
• /
• 2019

This study was conducted to identify disaster awareness, disaster preparedness, and ego-resilience in the college of nursing students', and to analyze correlation between study variables. The study subjects were 300 nursing students in four universities in two cities. Data were collected between April 1 and April 30, 2019 using by completing structured self report questionnaires. Data were analyzed using T-test, ANOVA, Pearson's correlation coefficient using SPSS/WIN 22.0. In correlation analysis, significant positive correlations were found between disaster awareness, disaster preparedness, and ego-resilience. Therefore, we propose to develop convergence education programs to imp rove disaster awareness, disaster preparedness, and ego-resilience in order to improve competency related to disaster management of nursing students.