• Korean Journal of Radiology
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• v.24 no.11
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• pp.1151-1163
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• 2023

Objective: To develop a deep-learning-based bone age prediction model optimized for Korean children and adolescents and evaluate its feasibility by comparing it with a Greulich-Pyle-based deep-learning model. Materials and Methods: A convolutional neural network was trained to predict age according to the bone development shown on a hand radiograph (bone age) using 21036 hand radiographs of Korean children and adolescents without known bone development-affecting diseases/conditions obtained between 1998 and 2019 (median age [interquartile range {IQR}], 9 [7-12] years; male:female, 11794:9242) and their chronological ages as labels (Korean model). We constructed 2 separate external datasets consisting of Korean children and adolescents with healthy bone development (Institution 1: n = 343; median age [IQR], 10 [4-15] years; male: female, 183:160; Institution 2: n = 321; median age [IQR], 9 [5-14] years; male: female, 164:157) to test the model performance. The mean absolute error (MAE), root mean square error (RMSE), and proportions of bone age predictions within 6, 12, 18, and 24 months of the reference age (chronological age) were compared between the Korean model and a commercial model (VUNO Med-BoneAge version 1.1; VUNO) trained with Greulich-Pyle-based age as the label (GP-based model). Results: Compared with the GP-based model, the Korean model showed a lower RMSE (11.2 vs. 13.8 months; P = 0.004) and MAE (8.2 vs. 10.5 months; P = 0.002), a higher proportion of bone age predictions within 18 months of chronological age (88.3% vs. 82.2%; P = 0.031) for Institution 1, and a lower MAE (9.5 vs. 11.0 months; P = 0.022) and higher proportion of bone age predictions within 6 months (44.5% vs. 36.4%; P = 0.044) for Institution 2. Conclusion: The Korean model trained using the chronological ages of Korean children and adolescents without known bone development-affecting diseases/conditions as labels performed better in bone age assessment than the GP-based model in the Korean pediatric population. Further validation is required to confirm its accuracy.

• Journal of Korean Ophthalmic Optics Society
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• v.10 no.3
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• pp.205-213
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• 2005

To evaluate the reliability of binocular vision measurements by phorometry. 90 students volunteered to participate in this study. 25 subjects were males, and 65 were females, they ranged in ages from 21 to 30 years. All subjects had normal ocular and systematic health, and all of them had at least 1.0 visual acuity with their best correction. At negative relative convergence(NRC) measurement in distance, the percentage of subjects is included in expected value(blur point/break point/recovery point) was 78%/61%/67%, divergence excess(DE) was 9%/31%/33%, and divergence insufficience(DI) was 13%/8%/9%, respectively. And positive relative convergence(PRC) measurement, includes expected value was 20%/46%/39%, convergence excess(CE) was 22%/14%/16%, and convergence insufficience(CI) was 35%/40%/45%. AC/A ratios of 42 subjects were normal. 38 were low, and the rest of them high. A low AC/A ratio is usually the result of a small vergence response in relation to accommodation. Negative relative convergence(NRC) at near, includes expected value was 26%/29%/44%, divergence excess(DE) was 61%/33%/24%, and divergence insufficience(DI) was 3%/38%/32%. And PRC at near, includes expected value was 33%/40%/31%, convergence excess(CE) was 61%/23%/42%, and convergence insufficience(CI) was 6%/37%/27%. For the near point of convergence(NPC) test, 58% of their subjects had a break of ${\leq}8cm$ with the accommodative target. In case of NRA(PRA) measurement, the expected value was 41%(33%). Accommodative insufficiency (AI) was 33%(43%), and accommodative excess(AE) was 26%(24%), respectively. AE was related to respectively low values of NRA. AI and CE are associated with high value of NRA, and the dysfunction of convergence excess combined with AE was related to a normal-high values of NRA. PRA in AI was related to a low value, wheres the dysfunction are associated with high values of PRA.

• International Journal of Concrete Structures and Materials
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• v.10 no.sup3
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• pp.97-108
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• 2016

When the energy performance of concrete is substantially higher than that of normal type concrete, such concrete is regarded as energy efficient concrete (WBSCSD 2009). An experimental study was conducted to investigate mechanical properties of energy efficient concrete with binary, ternary and quaternary admixture at different curing ages. Slump test for workability and air content test were performed on fresh concretes. Compressive strength, splitting tensile strength were made on hardened concrete specimens. The mechanical properties of concrete were compared with predicted values by ACI 363R-84 Code, NZS 3101-95 Code, CSA A23.3-94 Code, CEB-FIP Model, EN 1991, EC 2-02, AIJ Code, JSCE Code, and KCI Code. The use of silica fume increased the compressive strengths, splitting tensile strengths, modulus of elasticities and Poisson's ratios. On the other hand, the compressive strength and splitting tensile strength decreased with increasing fly ash.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.51-58
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• 2018

This study aimed to find the related factors of nursing students' self-efficacy(including general self-efficacy and social self-efficacy), self-leadership and academic performance. Collected data were analyzed using SPSS 19.0. The general self-efficacy scores of the subjects in who're admitted according to aptitude, higher school grades, extroverts, and higher leadership were significantly higher than those who weren't. The social self-efficacy scores were significantly higher in younger ages, extroverts and higher leadership. Self-leadership was higher in those who're admitted according to aptitude. Academic performance was significantly higher in the females and higher school grades. Social self-efficacy was positively correlated with self-leadership, and negatively with academic performance. Explanation rate of sex, general self-efficacy and social self-efficacy on academic performance was 10.5%. These results can be applied as a basis for developing guidelines of nursing students' self-efficacy, self-leadership and academic performance after repeated studies.

• The Research Journal of the Costume Culture
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• v.26 no.4
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• pp.632-648
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• 2018

This study aims to contribute to the development of sports wearables. It was conducted by a convergence team of professionals in the fashion industry, kinesiology and sports studies, and computer science and engineering. The purpose of the current study was to design and develop a fabric-type fitness band for a sensor to measure acceleration during jump rope exercises. Computer science and engineering professionals developed the Arduino board and sensor, kinesiology and sports studies provided the necessary exercise protocol, and the fashion industry professionals developed the band. First, a fitness band preference survey was completed by men and women between the ages of 20 and 50. Typical uses of the band included tracking exercise amount as measured by the number of steps taken and calories burned. Strap watch closure, a single color and achromatic color, and soft and smooth touch materials were preferred as band design. Second, two fabric-type fitness bands were designed and developed. Design 1 had a 3-dimensional pocket for the sensor, bright blue color, and stretch binding around the edges and for a loop. Design 2 had a flat pocket for the sensor, achromatic color, mesh binding around the edges and two metal loops. Both designs had Velcro as a closure. Third, wear testing of both bands with the sensor were conducted of 15 women in their 20s. They wore the bands during jump rope exercises. Both bands generally satisfied the participants. The Design 2 band was slightly more satisfying than the Design 1 band.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.251-259
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• 2018

This study aimed to identify the risk factors for cardiovascular disease (CVD) among age groups using the Framingham risk score (FRS). The research design used was a cross sectional descriptive study using the Sixth Korean National Health and Nutrition Examination Survey from 2013-2015. Data from 5211 men, between the ages of 30-74 was analyzed. After adjusting for age, the result of logistic regression analysis showed that obesity (OR=2.51 95% CI=2.05-3.07), physical inactivity (OR=1.71, 95% CI=1.39-2.10), heavy alcohol drinking (OR=1.33, 95% CI=1.09-1.62), and dietary fiber intake (OR=0.99, 95% CI=0.98-0.99) were presented as predictors of CVD. Obesity was considered to be a particularly important predictor of CVD for young and middle-aged men. This result will be used for developing intervention relating to lifestyle modification for young and middle-aged men.

• Journal of Digital Convergence
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• v.13 no.9
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• pp.515-521
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• 2015

In this study, we tried to analyze arterial stiffness of Jeju female divers who diver into cold water without the assistance of oxygen. For this purpose we measured pulse wave velocity and ankle-brachial index of Jeju female divers and same aged females who didn't have any cardiovascular risk for comparing the vascular stiffness. The results were the following : First, the light-femoral pulse wave velocity of Jeju female divers was significantly lower than normal women of the same ages. Second, Jeju female divers's ABI showed higher tendency than normal same aged women. These result showed that Jeju female divers' body had been completed for adaptation to low temperature and high pressure water environment through a long-term immersion activities in old age, as well as due to higher physical activity levels of Jeju female divers peripheral vascular resistance was not reduced.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.3
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• pp.319-329
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• 2018

Objectives: The object of this paper is to analyze difference of general and occupational characters, risk exposure and ill health symptom depending on the special type of employment. Methods: 50,007 participants from Fourth Korean Working Condition Survey conducted in 2014 was analyzed. Cross-tabulation analysis was conducted for deriving difference in general and occupational characters, mulitvariate logistic regression analysis was conducted after controlling general and occupational characters for deriving difference in risk exposure and ill health symptom depending on the special type of employment. Results: In the special type of employment, female, ages of 50, education levels of high school, monthly income of 2,000-3,000 thousand won, job types of sales person, enterprises of less than 100 workers, working duration of 2-10 years and long working hours worker's proportion was higher than general employment. Physical(OR: 0.84, 95% CI: 0.76-0.94) and ergonomic (OR: 0.48, 95% CI: 0.42-0.55) risk exposure was lower, psychological(OR: 1.77, 95% CI: 1.54-2.04) risk exposure was higher than general employment, and there was no significant difference between the special type of employment and general employment in chemical/biological risk exposure(OR: 1.06, 95% CI: 0.94-1.20) and ill health symptom(OR: 0.98, 95% CI: 0.89-1.09). Conclusions: This article offers the analysing difference between the special type of employment and general employment using huge size cross sectional data represent Korean employees.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.111-124
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• 2019

This study was conducted to identify the using self-nail products for the purpose of developing indicators to respond to changes in nail industry due to the evolution of consumption patterns caused by the spread of self-nail culture. The final analysis of 293 survey was conducted on female adults living in South Gyeongsang Province from September 1, 2018 to October 30, 2018. The study found that women in their 20s were more interested in nail care than in most cases. The main route of obtaining nail-related product information was the higher the use of SNS as the age was younger(${\chi}^2=185.048$, p<.001). According to a survey of 165 people who have experience with self-nail products, 53.3 percent of 'paste stickers' were the most common, followed by 39.4 percent of 'paste nail tips' and 7.3 percent of 'home care products'. Looking at the disadvantages of self-nail products, between groups under their 50s and over 50s group saw a significant difference(${\chi}^2=27.032$, p=.008). For those in their 50s or younger, 'the inconvenience of daily life' was considered a disadvantage. On the other hand, people in their 50s and older considered 'short duration' as a disadvantage. The lower the age, the higher the willingness to use continuously(${\chi}^2=14.308$, p=.006).We found that there were differences in preference for self-nail products according to age. It was noticed that there were differences in satisfaction and persistence. This suggests the need for more specific follow-up studies on the use of self-nail products by age group. Therefore, this research aims to present basic data for the development of direction and custom program for the professional nail industry to advance, thus providing basic data to help the development of nail industry in South Gyeongsang Province.

• Journal of Convergence for Information Technology
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• v.11 no.6
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• pp.181-187
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• 2021

As the aging society progresses and the functional cosmetics market is revitalized we have learned that the functional cosmetics that the silver generation is most interested in are wrinkle-improving products and we are making great efforts to develop functional cosmetics that improve wrinkles. The ingredients are actually making. From the early 2000s when the development of functional cosmetics began to the present the research trends of functional cosmetics for wrinkle improvement were analyzed by analyzing papers on functional cosmetics for wrinkle improvement. Research methods focused on literature search and SIRS paper search keywords. And the cosmetic material that needs to be researched focuses on the anti-aging function among functional cosmetics which is the anti-wrinkle function. The research results show the rapid growth of the Anti-aging market. As the population ages the generation of silver with high purchasing power will expand and a market for expensive anti-aging products and services for a healthy old age will be formed.