• The Korean Journal of Physiology
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• v.4 no.2
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• pp.37-44
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• 1970

Human body volumes were calculated from the measurments of body height and body weight. Equations Suited to express the relations of height, weight, and surface area to show the body volume were derived from the body volume measurements by means of underwater. weighing method. Underwater body weights were corrected for the residual volume of long obtained by the Rahn's three breath method. Underwater weighing was performed on 173 male subjects aged between 13 and 51 years. Subjects were divided into 4 age groups, namely, 13-16 years group of 47 subjects, 16-19 years group of 46 subjects, adult group aged between 22 and 38 years comprising 45 subjects, and middle-aged group (40-51 years) of 35 subjects. The group division was made on .the basis of physical growth and development. The following results were obtained. 1. Body height (H, cm), body weight (W, kg), body surface area $S,\; m^{2})$, and body volume (V, liter.) interrelated closely. V/S showed a high correlation with W/H and the coefficient of correlation was r=0.97 irrespective of age group differences of the subjects. The coefficients of correlation between V/S and W/H in the total mate subjects as a single group was r=1.983. Subsequently the following regression equation was obtained. V = S X (54.84 W/H + 14.08) The agreement of body volume values obtained by the calculation and underwater weighing in the total subject group was better than that of the separate age group division. 2. The calculated values of body volume were: 40.4 l (euiqvalent to the body density value of 1.0562 kg/1) in 13-16 years group; 52.0 l (equivalent to density value of 1.0723 kg/l) in 16-19 years group; 55.3 l (equivalent to density value of 1.0570 kg/l) In the adult group; and 54. 0 l (equivalent to density value of 1.074 kg/l) in the middle-age group. The mean deviation of calculated from the measured volume value ranged between ${\pm}0.55$ and ${\pm}0.81$ liters. 3. The correlation between V/S and mean skinfold thickness of 4 sites (arm, back, iliac and chest) was high, namely, the coefficient of correlation was r=0.656. The coefficients of correlation between V./S and the $R\"{o}hrer$ index ranged between r=0.668 and r=0.810 affected by the difference in group age of the subject. The body volume (V) alone correlated poorly than V/S with mean skinfold thickness (r=0.606) and the $R\"{o}hrer$ index (r ranged between 0.274 and 0.588).

• Korean journal of applied entomology
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• v.61 no.4
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• pp.549-554
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• 2022

Life table-related studies in insect ecology have been an interesting topic for insect researchers. Two calculation methods are commonly applied to estimate the intrinsic rate of natural increase (r_m) in the life table statistics. The first method is to estimate an approximate r_m by dividing the natural logarithm of the net reproductive rate (R₀) by mean generation time (T) (namely mean generation time-based method). Another approach is to apply the Lotka-Euler equation derived from the population growth equation of Lotka-Volterra to estimate accurate r_m using the maximum likelihood method (Lotka-Euler equation-based method). In the latter case, there is a difference in the estimated r_m value when the initial age class of the target cohort was set to "0" or "1", which confused the application. In this short review, a brief history of the calculation process of the life table was reviewed. It was again confirmed in the Lotka-Euler equation-based method that the form of $\sum\limits_{x=1}^{w}e^{-rx}l_xm_x=1$ should be applied to estimate r_m when the first age class was set to zero, while the form of $\sum\limits_{x=0}^{w}e^{-r(x+1)}l_xm_x=1$ when set to one.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.2
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• pp.250-260
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• 2003

The purposes of this study were to classify the contents of shopping orientation of cosmetics, to group women into shopper types of cosmetics, to investigate the differences in cosmetics purchase behavior according to shopper types, and to examine how the cosmetics satisfaction was influenced by cosmetics shopping orientation and demographic variables. Subjects were 479 women in their 20's to 50's in Seoul, Korea. The factors of the shopping orientation of cosmetics derived by factor analysis:'impulsive shopping','conspicuous shopping','rational shopping', and 'independent shopping. Four shopper types were classified by cluster analysis of the 4 factors. The shopper types were the same as the 4 factors. total satisfaction of cosmetics was influenced by independent shopping orientation, age, brand, impulsive shopping orientation, conspicuous shopping orientation, and rational shopping orientation(R2=.217). Satisfaction of basic cosmetics was influenced by conspicuous shopping orientation. independent shopping orientation. age. rational shopping orientation, impulsive shopping orientation, and social class(R2=.407). Satisfaction of coloring cosmetics was influenced by brand, independent shopping orientation, age, and impulsive shopping orientation(R²=.167).

• International Journal of Contents
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• v.8 no.3
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• pp.26-33
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• 2012

The animal naming test (ANT) is known to be influenced not only by age, gender, and education but only by ethnicity, culture, and language. Thus, population-specific norm considering these variables needs to be developed for Korean-speaking elderly. We evaluated 185 healthy elderly people with five measures. Education was the single statistically independent correlate of the total number of words ($R^2$ = .312, p = .038). After adjusting for education, there was slightly significant negative correlation (r = -.215, p = .049) between age and total number of words. Mean number of words produced was $13.71{\pm}3.09$. The production frequency was negatively correlated with the typicality rating (r = -0.41, p < .05). The concrete and exact scoring rule could be set up in the comparison of naming performance between a normal and patient with neuro-linguistic disorder and its data could be utilized in a differential diagnosis for patients with neurological disorders.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.8 no.1
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• pp.7-23
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• 2001

This study was done to provide basic data on prevention of breast cancer by identifying and analyzing risk factors for breast cancer in Korean women. The data were collected from three hospitals. The data from Jan. 1995 to Dec. 1997 was based on the patient recordings and personal contacts if possible. Data from 1998 to 1999 was collected from 280 inpatients and outpatients diagnosed as breast cancer. From this data, information about the risk factors of breast cancer could be acquired. The factors are scaled according to the degree of risk. Menstrual history, obstetrical history, family history. lactation period, life style were given 5 point, and body mass index was given 4 point. Using one-way ANOVA. the most important risk factors were identified and analyzed by multiple regression. The conclusion of this study are as follows : General factors which would show an effect on the results of the multiple regression included risk factors such as menstrual history, obstetrical history, lactation period, family history, and life style factors including mortal state, monthly income, educational level, job and age. Family history(R=0.481) was found to be the highest risk factor(23.1%) affecting breast cancer risk. The next factors were dying hair(R=0.603), drinking(R=0.846), body mass index(R=0.885), smoking(R=0.916), age of menopause(R=0.937), pregnancy age of first full-term(R=0.957), eating vegetable(R=0.980) and the number of full term pregnancies in that order. The sum total(R=0.986) of all the above factors accounted for 97.3% of the risk of breast cancer for Korean women. In conclusion, it was found that family history and dyeing hair were the highest risk factors for breast cancer. It is recommended that those with a family history of breast cancer should have regular breast examinations, and those who often dye their hair should reconsider this practice.

• Journal of Technology Innovation
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• v.30 no.3
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• pp.1-34
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• 2022

This study examines the effect of CEO age on the value relevance of R&D which is the relationship between R&D expenditures and firm value. The value relevance of R&D expenditures is higher in companies with current older CEOs, while the relationship in companies with younger CEOs is lower than that of other companies. These results suggest that older CEOs tend to be conservative and make prudent R&D investment decisions. Because they make systematic investment decisions with rich experience, they are expected to have higher investment performance in the market. On the other hand, young CEOs choose risky investments in order to have their abilities highly evaluated in the labor market. The market places a high degree of risk on the R&D decision-making of young CEOs. Next, we analyze whether the age of the replaced CEOs affects the relationship between R&D expenditures and firm value. The result shows that the change of management increases the effect of R&D expenditure on firm value. However, in the case of being replaced by a younger CEO, this positive relationship becomes lower than that of other companies, showing results consistent with the case of the current younger CEO. The samples are analyzed by dividing them into conglomerates and non-conglomerates. In conglomerates, the age of the replaced CEOs does not affect the value relevance of R&D expenditures. Only non-conglomerates showed a negative (-) effect on the replaced younger CEOs. These results suggest that conglomerates maintain the stability of R&D management and performance so that the performance of R&D expenditures is not significantly affected by the age of the replaced CEOs. The reason is that mutual checks and support are coordinated within the group through decentralization of work and systematization of decision-making. This study shows evidence that the relationship between R&D expenditure and firm value according to the age of the replaced CEO is a phenomenon that only occurs in non-conglomerates. This phenomenon suggests that conglomerates are stably managing their R&D performance regardless of the change of CEOs or the characteristics of the CEOs.

• Korean Journal of Child Studies
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• v.10 no.1
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• pp.26-42
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• 1989

This study was designed to investigate the relation between mother's interaction strategies and self-regulation of young children from a Vygotskian perspective. The hypotheses of this study were: 1) The self-regulation of young children will improve with increase in age, 2) the use of mothers' interaction strategies will increase as child's age decreases, 3) mothers' directiveness in the mother-child interaction depends on the age of child and socio-economic level, and 4) mothers' directiveness in the mother-child interaction will have negative relationship with child's self-regulation. The subjects of this study were 60 mother-child dyads with three different age-of-child groups (3-, 4-, and 5-year-olds). They were further divided into higher and lower socio-economic groups. A puzzle task was used for the measurement of self-regulation. The task consisted of two identical puzzles with one used as the model. The collected data were analyzed by ${\chi}^2$, one-way and two-way analysis of variance, and Pearson's r. Self-regulation of the young children improved with increase in age (P < .05). The use of mothers' interaction strategy decreased as the children's age increased (P < .05). Mothers' directiveness in the mother-child interaction was influenced by the age of child (P < .01) and by socioeconomic level (P < .05). There was a negative correlation (r=-.848) between the mothers' directiveness in the mother-child interaction and the child's self-regulation (P < .001).

• Research in Community and Public Health Nursing
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• v.1 no.1
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• pp.582-594
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• 1989

The purpose of this study is to analyze the factors affecting the school health teachers' self-confidence. This study was conducted with 87 school health teachers working in Jeonbuk province, from September to December, 1986, The results are follows; 1. Demographic characteristics of school health teachers 1) Age mean ; 34, range; 23-54 2) School Nursing experience mean; 11 years, range; 0-24 3) Clinical experience mean; 1.5 years, range: 0-13 2. Status of school health resources & nursing activities 1) Personnel resource school health teacher: pupils : 1 : 1,436 'classes=1:31 'general teacher=1:39 2) Budget Total school operating budget: School health budget : 100 : 4.2 (52.2 thousand Won) Half of the school health budget expend on medicine. 3) Clinic 80% of all schools have health clinic seperately. 71.32 of all schools have less than $35m^2$, 23.9%, $36-66m^2$. 4) Only 20% of all schools have organization for health 5) Average of clinic visitor for 1 year; 2,084 Major problem is on digestive system. And other problem: respiratory, skin, musculo - skeletal system, dental problem, etc... 6) Literal message for 1 year; 12 times. For health education (4), vaccination (3), examination of parasites (2), etc... 3. The degrees of the school health teachers' self-confidence 1) Program planning & evaluation; 2.9. 2) Clinic management; 2.8 3) Health education; 2.8 4) Management of school environment; 2.7 5) Health care services; 2.5. 6) Operating of school health organization; 2.3 4. Significances to self-confidence on school health nursing activities 1) Program planning & evaluation: home message (r=.228, p<.05) No. of clinic visitor (r=.220, p<.05) expending time for clinic management (r=.229, p<.05) religion (t: 2.5, p<.05) level of school (F=6.3, p<.005) 2) Clinic management: age of school health teacher (r=-.202, p<.05) school health experience (r=-.211, p<.05) salary step (r=.187, p<.05) expending time for clinic management (r=.315, p<0.1) marital status (t=3.97, p<.005) level of school (F=3,139, p<0.5) 3) Management of school environment: level of school (F=3.899, p<.05) expending time for clinic management (r=-,216, p<0.5) 4) Health care service: age of school health teacher (r=-.186, p<.05) marital status (t= 3.67, pH.005) 5) Health education: expending times for clinic management (r=-.252, p<05) level of school (F=5.343, p<.01) 6) Operating of health organization; age of school health teacher (r=-.258, p<.01)salary step (r=.188, p<.05) Based on the above results, the suggestions are as follows; 1. Need to raise ,appointment rate school health teacher. 2. Need to raise self-confidence on school health nursing activities through the inservice education or re-inforcement. 3. Need to secure adequate budget for school health. 4. Participation of school health teacher and support of school master for school health services are required. 5. Need for use the health clinic seperately, adequate facilities and free utilization by visitors.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.315-320
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• 2013

We have investigated the variation of spherical aberration of the anterior and posterior surface in a Korean sample population with various age between 20 to 71 years old. We used Pentacam (Oculus Inc., Germany) to measure the corneal radius, asphericity, and spherical aberration of 290 patients with normal cornea. There were negative correlation between corneal anterior radius and spherical aberration(r = -0.22, p<0.0001), and, there were negative correlation between corneal posterior radius and spherical aberration(r=-0.27, p < 0.0001). There were positive correlation between anterior asphericity and spherical aberration(r = 0.24, p < 0.0001), however there were negative correlation between posterior asphericity and spherical aberration(r = -0.17, p=0.00288).The average of anterior spherical aberration and posterior spherical aberration was $0.482{\pm}0.099{\mu}m$ and $-0.098{\pm}0.029{\mu}m$. The average of spherical aberration was $0.385{\pm}0.097{\mu}m$. There were significant positive correlations between anterior spherical aberration and age(r = 0.227, p<0.0001), and there were positive correlations between posterior aberration and age(r = 0.349, p<0.0001). It is considered that this data can be used as basic information for furture studies for improving the quality of vision of modern human and, through the analysis of the spherical aberration of cornea was to provide a better understanding of the optical part of the Korean's eye.

• Dementia and Neurocognitive Disorders
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• v.21 no.4
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• pp.138-146
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• 2022

Background and Purpose: Magnetic resonance imaging (MRI) helps with brain development analysis and disease diagnosis. Brain volumes measured from different ages using MRI provides useful information in clinical evaluation and research. Therefore, we trained machine learning models that predict the brain age gap of healthy subjects in the East Asian population using T1 brain MRI volume images. Methods: In total, 154 T1-weighted MRIs of healthy subjects (55-83 years of age) were collected from an East Asian community. The information of age, gender, and education level was collected for each participant. The MRIs of the participants were preprocessed using FreeSurfer(https://surfer.nmr.mgh.harvard.edu/) to collect the brain volume data. We trained the models using different supervised machine learning regression algorithms from the scikit-learn (https://scikit-learn.org/) library. Results: The trained models comprised 19 features that had been reduced from 55 brain volume labels. The algorithm BayesianRidge (BR) achieved a mean absolute error (MAE) and r squared (R²) of 3 and 0.3 years, respectively, in predicting the age of the new subjects compared to other regression methods. The results of feature importance analysis showed that the right pallidum, white matter hypointensities on T1-MRI scans, and left hippocampus comprise some of the essential features in predicting brain age. Conclusions: The MAE and R² accuracies of the BR model predicting brain age gap in the East Asian population showed that the model could reduce the dimensionality of neuroimaging data to provide a meaningful biomarker for individual brain aging.