• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.380-387
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• 2001

The characteristics of ecological niche, breadth and overlap, for seventeen major tree species were evaluated in the natural deciduous forest in Mt. Chumbong area. Employed by the plot sampling method, the environmental gradient for vertical niche was based on the intensity of light within the forest, and that for horizontal niche was based on multi-dimensional resources in distribution pattern. The result showed that Fraxinus rhynchophylla had the highest value of vertical niche breadth and Maackia amurensis had the lowest, and Acer pseudo-sieboldianum had the highest value of horizontal niche breadth and Betula costata had the lowest. There was no significant correlation between both measures of niche breadth. However, the tolerance index for each species was positively correlated to the values of niche breadth. Spearman's rank correlation coefficients were applied to test the correlationship between the species ranks of tolerance index and those of two ecological niche breadths. The coefficient of $r_s=0.432$ ($P{\leq}0.1$) was not enough to support significant correlationship between the tolerance index and vertical niche breadth at the 95% probability. If Carpinus cordata, rarely reach canopy of the forest due to its own growth form, are excluded from the analysis, coefficient was calculated as $r_s=0.650$ ($P{\leq}0.01$), resulting in highly significant correlationship. The Spearman's rank correlation coefficient was $r_s=0.797$ ($P{\leq}0.01$) for tolerance indices and the values of horizontal niche breadth, indicating highly significant. Four distinctive species groups, produced by cluster analysis on the basis of ecological niche overlap for each pair of species, were in considerable accord with the positively associated species constellation pattern created by the inter-species association analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1682-1685
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• 2005

System algorithms estimated by deterministic input may occur the error between predicted and actual output. Especially, actual system can't predict the exact outputs due to uncertainty and tolerance of input parameters. A single output to a set of inputs has a limited value without the variation. Hence, we should consider various scatters caused by the load assessment, material characteristics, stress analysis and manufacturing methods in order to perform the robust design or estimate the reliability of structure. The system design with uncertainty should perform the probabilistic structural optimization with the statistical response and the reliability. This method calculated the probability distributions of the characteristics such as stress by combining stress analysis, response surface methodology and Monte-Carlo Method and got the probabilistic sensitivity. The sensitivity of structural response with respect to inconstant design variables was estimated by fracture probability. Therefore, this paper proposed the probabilistic reliability design method for fracture of uncorved freight end beam and the design criteria by fracture probability.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.35.1-35.11
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• 2023

Background: Cardio-cerebrovascular diseases (CVDs) are the most common cause of death worldwide. Various CVD risk assessment tools have been developed. In South Korea, the Korea Occupational Safety & Health Agency (KOSHA) and the National Health Insurance Service (NHIS) have provided CVD risk assessments with health checkups. Since 2018, the KOSHA guide has stated that NHIS CVD risk assessment tool could be used as an alternative of KOSHA assessment tool for evaluating CVD risk of workers. The objective of this study was to determine the correlation and agreement between the KOSHA and the NHIS CVD risk assessment tools. Methods: Subjects of this study were 17,485 examinees aged 20 to 64 years who had undergone medical examinations from January 2021 to December 2021 at a general hospital. We classified subjects into low-risk, moderate-risk, high-risk, and highest-risk groups according to KOSHA and NHIS's CVD risk assessment tools. We then compared them with cross-analysis, Spearman correlation analysis, and linearly weighted kappa coefficient. Results: The correlation between KOSHA and NHIS tools was statistically significant (p-value < 0.001), with a correlation coefficient of 0.403 and a kappa coefficient of 0.203. When we compared risk group distribution using KOSHA and NHIS tools, CVD risk of 6,498 (37.1%) participants showed a concordance. Compared to the NHIS tool, the KOSHA tool classified 9,908 (56.7%) participants into a lower risk category and 1,079 (6.2%) participants into a higher risk category. Conclusions: In this study, KOSHA and NHIS tools showed a moderate correlation with a fair agreement. The NHIS tool showed a tendency to classify participants to higher CVD risk group than the KOSHA tool. To prevent CVD more effectively, a higher estimation tool among verified CVD risk assessment methods should be selected and managements such as early intervention and treatment of risk factors should be performed targeting the high-risk group.

• Journal of Korea Technology Innovation Society
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• v.1 no.2
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• pp.208-219
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• 1998

In the light of the strategic utilization of the national R & D projects, this paper is to induce the spin-off strategies to improve the national R & D effectiveness through analyzing the spin-off characteristics of nuclear technologies, the spin-off status of the advanced countries and the case study of Korean nuclear spin-offs. Spin-off process is viewed as a three-stage operation, such as preparation stage, implementation stage and maintenance stage. In order to find the correlation between the influencing factors and spin-off effectiveness, the Spearman's correlation coefficient was employed as a specific statistical technique. By integrating this correlation, spin-off process and spin-off strategies, this paper presents an efficient framework to improve the spin-off effectiveness.

• Journal of the Korean Home Economics Association
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• v.35 no.6
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• pp.235-248
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• 1997

This study was aimed to validate the Infant/Toddler Environment Rating scale (ITERS). The rating scale was translated and adjusted appropriately by two researchers majoring child studies. An item-by-item comparison of the ITERS with criteria of NAEYC was conducted as the measure of content validity. 88% of the items of the ITERS was covered on the NAEYC criteria. Criterion validity was assessed by comparing ITERS scores and the Assessment Profile for early childhood Programs scores. The total correlation of two scores was .87. The sample for the inetrater reliability and internal consistency studies included 30 infant/toddler classes in 30 day care center in Inchon city. Two observers independently rated each class on the ITERS during a single visit. The Spearman's correlation coefficient for interater reliability on the overall scale was .74. For the measure of internal consistency, the Cronbach's Alpha score on the overall scale was .93. The rating results show that national/public child care centers have better quality in Adult Needs and Learning Activities subscales than private child care centers have.

• Journal of the Korean Society of Radiology
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• v.14 no.7
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• pp.871-879
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• 2020

The purpose of this study was to analysis the correlation between kidneys function indicators and these size in ultrasonography. A total of 170 (male:86, female:84) patients of sex and age groups were examined by abdominal ultrasonography. The patients classified as those in their 20's, 30's, 40's, and over 50's. We measured the length, width, and cross-sectional height of the kidneys twice. At this time, the length of these were measured from the maximum upper to the maximum lower pole and the widest width in the same ultrasonography was measured to obtain the cross-sectional area. Other relevant indicators included body surface area, serum creatinine, glomerular filtration rate (GFR), MDRD (Modification of diet in renal disease) and C-G (Cockcroft-Gault). Significant comparisons of differences between relevant factors by age groups and sex were conducted with a one-way distribution analysis. Correlation analysis was also performed between relevant factors by using Pearson and Spearman correlation coefficient. It was defined as meaningful when the p-value was less than 0.05. As a result, the length, the width, and the cross-sectional area of kidneys were correlated with GFR, C-G, MDRD. Therefore, it is expected that the accuracy of diagnosis of kidneys disease will be increased if the relevant indicators are evaluated together rather than measuring only length of these in ultrasonography.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.355-361
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• 2015

Background: Deletion types of genetic variants of glutathione S-transferase (GST) M1 and T1, the GSTM1 null and GSTT1 null which are risk factors for certain cancers, have been ubiquitously found in human populations but their worldwide distribution pattern is unclear. Materials and Methods: To perform a meta-analysis, a systematic search for the literature on GSTM1 and GSTT1 null genotypes was done to identify 63 reports for 81 human populations. Relationships between the GSTM1 and GSTT1 null genotype frequencies and the absolute latitude of 81 populations were tested by Spearman's rank correlation coefficient. Results: A significant positive correlation was detected between the GSTM1 null genotype frequency and the absolute latitude (r=0.28, p-value <0.05), whereas the GSTT1 null genotype frequency and absolute latitude showed a significant negative correlation (r= -0.41 p-value <0.01). There was no correlation between the frequencies of GSTM1 and GSTT1 null genotype in each population (r= -0.029, p-value=0.80). Conclusions: Latitudinal clines of the distribution of the GSTM1 and GSTT1 null genotypes may be attributed to the result of gene-environmental adaptation. No functional compensation between GSTM1 and GSTT1 was suggested by the lack of correlation between the null frequencies for GSTM1 and GSTT1.

• Journal of Preventive Medicine and Public Health
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• v.40 no.2
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• pp.169-176
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• 2007

Objectives : This study was conducted to elicit quality weights for 42 EQ-5D health states with the time trade-off (TTO) method from the general population of South Korea. Methods : We selected the same EQ-5D health states as those in the UK MVH study. The Korean version of EQ-5D questionnaire and TTO method were used for the valuation process. We interviewed 500 people as a representative sample of the general population in Seoul and Gyeonggido. The result was compared with those from UK, Japan, and USA by Spearman's rank correlation and t-test. Results : TTO values for 42 EQ-5D health states and 'unconscious' state were obtained from the general South Korean population. The best one was '11112' state and the worst one was 'unconscious' state. The states worse than death were '33323', '33333', and 'unconscious' states, which had negative TTO values. There was a strong correlation between TTO values of the EQ-5D health states and those of their corresponding states from UK, Japan, and USA (Spearman's correlation coefficient: 0.885, 0.882, and 0.944, respectively, p <0.001). However, absolute TTO values of most EQ-5D health states were significantly different from those of their corresponding states in other foreign studies (UK : 41/42, USA : 32/42, Japan : 15/17). Conclusions : We found that the Korean general population TTO values for EQ-5D health states were different from those of other foreign studies, suggesting that a specific Korean valuation set should be developed and used for economic evaluation studies in South Korea.

• Journal of Korean Library and Information Science Society
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• v.24
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• pp.1-44
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• 1996

This study is to analyze correlations between 10 factors related to university libraries and the number of professional staff, nonprofessional staff, and total library staff of university libraries in Korea and United States of America. The results of this study are summarized as follows: 1. In the case of Korea, there are high positive correlations between the number of total library staff and 7 of 10 variables (coefficient : 0.76-0.99) ; between the number of professional staff and 7 of 10 variables, same as the above (coefficient : 0.76-0.99) ; between the number of nonprofessional staff and 4 of 10 variables (coefficient 0.73-0.93). In the case of America, there are high positive correlations between the number of total library staff and 6 of 10 variables (coefficient : 0.74-0.97) ; between the number of professional staff and 5 of 10 variables (coefficient : 0.78-0.87): between the number of nonprofessional staff and 6 of 10 variables (coefficient : 0.73-0., 96). 2. All the. rank orders of correlation coefficients of two countries show little significant difference, by the results of the Spearman's Rank Order Correlation analysis (coefficient : total staff, 0.9152: professional staff, 0.8667 ; nonprofessional staff, 0.9030) 3. In the case of Korea, among the above factors, correlations of the total university expenditure and the library expenditure show a significant difference more than ones of the other factors. On the other hand, in the case of American professional staff, the correlations of the library expenditure, the library materials expenditure and the volumes in library show a significant difference more than ones of the other factors, while in the case of American nonprofessional staff, only the library expenditure shows a significant difference more than the others. 4. In the results of the correlation analysis between the professional staff and nonprofessional staff in Korea, the number of graduate enrollments, volumes in library, library expenditure and total university expenditure show higher positive correlation to the professional staff than the nonprofessional staff. However, in the case of America, the library expenditure and the library materials expenditure show higher positive correlation to the nonprofessional staff than the professional staff, while the university expenditure per student shows higher positive correlation to the professional staff. 5. In the results of the correlation analysis between Korea and America, in the case of the total library staff, the undergraduate enrollments, the total university expenditure and the library expenditure show higher positive correlation to Korea than America, and in the case of the professional staff, the graduate, enrollments, the volumes in library and the above 3 factors also show higher positive correlation to Korea than America. But in the case of the nonprofessional staff, the graduate enrollments, the volumes in library and library materials expenditure show higher correlation to America than Korea, while the total university expenditure shows the o n.0, pposit phenomenon of the above. And the other factors by the type of staff are little significant difference between two countries.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.10 no.2
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• pp.154-163
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• 1999

GRBAS scale, the tool fir the perceptual evaluation of voice, demands the experience of judges, and MDVP parameters of CSL, the tool for the objective measurements of voice quality demands the exact interpretation of the analyzed results. The two tools should be used as compensatory evaluation methods, so the experimental study was performed to investigate the correlation between GRBAS scales and MDVP parameters by using the pathologic voice of the 30 patients with vocal polyps, and to know the significant MDVP parameters which the inexperienced GRBAS scale judges should attend to. The 30 subjects voices, saved in MDVP of CSL were analyzed by its own analysis program, and three experienced voice therapists judged the same voices by using GRBAS scales. The correlations between them were analyzed by Spearman Rank Correlation Coefficient. As results, among the 29 MDVP parameters, 22 parameters showed statistically significant correlation with Grade(G) scale(p＜0.05). And it was found that Roughness(R) scale showed significant correlation with 18 parameters, Breathiness(B) scale with 17 parameters, Strain(S) scale with 12 parameters. In Asthenicity(A) scale, no parameter showed significant correlation. On the whole, significantly high correlation were found in the parameters related with pitch ind amplitude perturbation, especially, the amplitude perturbation.