• Journal of Technology Innovation
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• v.29 no.3
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• pp.1-31
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• 2021

With the growing importance of technology innovation as a key factor for firms' competitive advantage, 'innovation persistence' became also an important research subject. 'Innovation Persistence' is a concept that indicates whether or not firms' innovation activity or performance continues. However, the data used for innovation studies are carried out as cross-sectional surveys in most countries. For this reason, studies dealing with longitudinal aspect of innovation persistence are rare. In particular, there is almost no research on innovation persistence using Korean innovation survey data. This study reviews the concepts and characteristics of innovation persistence based on extant literature, and perform an empirical analysis on the status and features of Korean firms' technology innovation persistence. Based on the data of the Korean Innovation Survey (KIS) conducted every other year from 2012 to 2018, panel data on 3,379 firms which observed multiple times are constructed. As a result, only part of the firms with persistent innovation were observed (for innovation performance 10~12%, for innovation activity 15~17%), and it was found that the persistence of non-innovation was remarkable(about 52~57%). And it was confirmed that the persistence of innovation activities is stronger than that of innovation performance. Besides, some features by sub-types of innovation appeared. Product innovation showed higher persistence than process innovation, and internal R&D also showed higher persistence than joint/external R&D. As a result of additional logit analysis to identify factors, it was found that radical or gradual product innovation is the most influential factor in persisting innovation in the next period. Since the sample selection bias due to a limitations of raw data might exist in the panel data constructed in this study, it should be noted that faulty generalization of the results are not allowed. Nevertheless, this is the first study to examine the technology innovation persistence targeting Korean firms and is expected to be a starting point for follow-up studies. It is anticipated that advanced research results will be drawn through the establishment of official panel data and improved methodologies.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.22-47
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• 2014

This study was to understand the basic principles of the East Asian wooden structure system research and analysis. The Korea and China ancient architecture internal structure research that the combination of girders and crossbeams position. The ancient wooden structures of eastern Asian countries, Korea and China are not much different from each other in the principles of the wooden architecture structure, combining pillars, purlins and crossbeams. However, it seems that age-division, local-division, national-division differs in detail techniques. China ancient wooden structures combination of purlin and crossbeam, and So-seul Timber(Chinese name: Chashou叉手, Tuojiao 托脚) seems to show differences according to the age of the fulcrum position, detailed approach is also different according to various historical dynasty. Before in the 15th century, Purlin and Crossbeam are coupled to each other, but since the 15th century, seems to have developed a technique combined with each other Girder and Crossbeam and to prevent buckling of the Crossbeam cross-sectional area increased dramatically. For Tuojiao in China Tang-Wudai dynasty(A.D. 618~979), can see that saw the top position Girder and Tuojiao no direct coupling, can be seen as maintaining the safety of the material than the material of the inner wooden structures prevent buckling of the purlin. Korea ancient wooden structures of Goryeo dynasty(A.D. 918~1391), So-seul Timber(Chinese name Tuojiao) why do not to use the fashion? To use Purlin Lower backing material techniques to prevent buckling is a popular trend to stable can be thought of as a preferred way to maintain. I think that with universality beyond the local-division, national-division and the two countries since the 15th century of Korea and China ancient wooden structures detailed mechanism for the purlin buckling. In middle-late Chosen dynasty, The effect of Deotgeolyi- techniques and fleeting beams reduce the purlin buckling that reduces the load transmitted from purlin and crossbeam of how to reduce the load on the roof portion of the architecture fleeting beams used, which of craftsmanship of the Chosen Dynasty building can be referred to as another technique for preventing buckling purlin. This Korea and China ancient architecture purlin beam structure and material So-seul Timber study. Seems to be able to provide a basic research study to restore and designed the old wooden architectures.

• Journal of agricultural medicine and community health
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• v.46 no.1
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• pp.12-22
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• 2021

Backgrounds: Proper distribution and supply of physicians are factors that affect national health care systems. This study investigated the payment distribution levels and the determinants that influence the salary levels of hospital hired physicians. Methods: We analyzed 4,014 job advertisements posted on an internet invitation information site about physician recruitment from May 2016 to May 2019. We used univariate analysis to determine the relationship between average monthly salary and the other related variables. Multiple regression analysis was used to determine the predictors of physician salary level. Results: The average monthly salary for the service physician was 15.4 million won, highest for orthopedic surgeons with 22.24 million won, and lowest for diagnostic laboratory physician with 11.4 million won. The factors significantly associated with average monthly salary were; non-major specialty, housing provision, no severance pay, and incentives(p<0.05). Non-major specialty, incentives, and the regions were predictors of the average standardized monthly salary(p<0.05). Conclusion: Factors associated with average monthly salary as revealed by this study were; medical specialty, hospital regional location, housing provision, payment of retirement allowance, and payment of other incentives respectively. However, this study was a cross-sectional study, and further studies will be required.

• Korean Journal of Community Nutrition
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• v.28 no.1
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• pp.38-47
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• 2023

Objectives: This study examined the association between the experience of disease management education and the use of nutrition labels according to the sociodemographic characteristics and health behaviors of people diagnosed with hypertension and diabetes living in the community. Methods: Among the participants from the Community Health Survey (2018), 74,283 individuals diagnosed with hypertension or diabetes were included in the study population. According to gender, this study evaluated nutrition label use by the experience of disease management education, individual sociodemographic characteristics, and health behavior. Finally, using multiple logistic regression analysis, the association between disease management education and nutrition labels was calculated using the odds ratio (OR) and 95% confidence interval (CI). Results: Males (24.5%) experienced more disease management education than females (22.6%). In addition, younger age, higher education level, and higher equalized personal income experienced more disease management education (P < 0.001). The educational experience rate was higher in the male subjects who did not smoke or were involved in high-risk alcohol consumption (P < 0.001). In addition, the rate of disease management education experience was significantly higher for both men and women who exercised by walking (P < 0.001). The use of nutrition labels was higher in females (9.9%) than males (5.8%), and both males and females were significantly higher in young age, high education, high income, and professional and office positions (P < 0.001). The utilization rate of nutrition labels was high in non-smoking male subjects and high-risk-drinking female subjects. In addition, the utilization rate of nutrition labels was significantly higher in males and females who exercised by walking and those who experienced disease management education (P < 0.001). After adjusting for individual sociodemographic characteristics, health behavior, and disease management education, the use of nutrition labels was high among females (OR 3.19, 95% CI 2.85-3.58), high income (Q4; OR 1.62, 95% CI 1.41-1.87, Q5; OR 1.58, 95% CI 1.37-1.84) and highly educated (high school; OR 2.87, 95% CI 2.62-3.14, above college; OR 5.60, 95% CI 5.02-6.23) while it was low in the elderly (OR 0.43, 95% CI 0.40-0.47), and economically inactive (OR 0.86, 95% CI 0.76-0.96). The use of nutrition labels was high in non-smokers (OR 1.29, 95% CI 1.13-1.48), nonhigh-risk drinkers (OR 1.22, 95% CI 1.08-1.38), and subjects who exercised walking (OR 1.44, 95% CI 1.34-1.54). There was no difference in the utilization rate of nutrition labels according to obesity, and the utilization rate of nutrition labels was significantly higher in subjects who had experienced disease education (OR 1.34, 95% CI 1.24-1.44). Conclusions: Education on the use of nutrition labels, which contributes to food selection for healthy eating, might be a tool for dietary management. Moreover, the utilization rate can be a good indicator for predicting the proportion of the population practicing the guide for disease management. Improving the utilization rate of nutrition labels through disease management education can be a useful intervention for people with chronic diseases who need healthy eating habits for disease management and preventing complications, particularly those diagnosed with hypertension and diabetes.

• Journal of Nutrition and Health
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• v.55 no.6
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• pp.656-669
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• 2022

Purpose: This study investigates the relationship between sleep duration, sleep quality, time use, and dietary quality of adolescents. Methods: A cross-sectional study was conducted, enrolling 423 high school students (112 male and 311 female students) in Chungnam using a questionnaire comprising general characteristics, sleep status, use of time, and Nutrition Quotient for Korean Adolescents (NQ-A). Results: On weekdays, male students reported getting 6.6 hours of sleep, which was significantly higher than the 5.8 hours reported by female students. The sleep quality score between male and female students was not significantly different on weekdays and weekends. Comparing the students categorized as getting 6 hours of sleep duration on weekdays and 8 hours on weekends, a significantly higher total NQ-A score was obtained for the long sleep duration group of female students on weekdays. In male students who reported increased screen time on weekdays and study time on weekends, there was a greater frequency of short sleep duration. Our data also revealed that the longer the sleep duration higher the NQ-A score. In addition, higher NQ-A scores were determined with shorter screen time and more prolonged exercise time. Conclusion: Our results suggest that intense study time and excessive use of smartphones have a negative effect on sleep in high school students. In addition, poor sleep quality and lack of sleep are likely to affect eating habits and nutritional status. Therefore, there is a need to provide nutritional education to adolescents imparting knowledge that associates desirable sleep habits and the correct use of time.

• Women's Health Nursing
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• v.7 no.2
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• pp.212-228
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• 2001

This is a cross-sectional descriptive correlation study that aimed to understand the relationship between the level of sexual contacts during the dates and psycho-social factors in teenage girls who have or had boyfriends. The purpose of this study was to describe the relationship between sexual contacts and self-esteem and self- assertiveness. The subjects of the study were 6,130 teenage girls who have or had boyfriends. They were selected convienently 12,733 teenage girls from 254 secondary schools located in 7 large cities and 9 provinces in Korea. A structured questionaire was used it included items one general characteristics, the levels of sexual contacts, self-esteem and self-assertiveness. Seven levels of sexual contacts were rated they were holding a hand, putting arms around each other's shoulders, kiss, french kiss, touching breast, petting genitalia, and sexual intercourse during the dates. Self-esteem and self-assertiveness were measured by the "Self-esteem scale" of Rogenberg (1971) and the questionaires developed by S. B. Chang et al(2000), respectively. The self-reported questionaires were collected from October 2, to October 28, 2000 and analyzed by using SPSS 10.0 Program. The data were analyzed by descriptive statistics, reliability, One-way ANOVA with Duncan method & Scheffe method. The results of the analysis were as follows. 1.An average Percentage of the respondents who have (46.1%) or had (53.9%) boyfriends was 48.1% (n=6,130) and the most common sexual contact during the dates was french kiss (26.7%, n=1,634). While 7.5%(458) of respondents had a sexual intercourse, 13.7%(842) of respondents didn't have any sexual contact during the dates. 2. Distribution of starting point of the first sexual contact demonstrates that 1,950 respondents (31.8%) held partner's hand at the first date and 1,367 respondents (22.3%) put arms around each other's shoulders at the 2nd or 3rd date. Sexual contacts such as kiss, french kiss, touching breast, petting genitalia, or sexual intercourse were experienced mostly at the later than the 10th date. However, surprisingly large number(1.7%) of respondents had genital contact and sexual intercourses at the first date. 3. The means of self-esteem and self-assertiveness socres of the respondents who have or had boyfriends are 27.43$({\pm}4.03)$ and 17.96$({\pm}2.55)$, respectively. The range of scores for self esteem was 10-40, 40 with most self esteem. The range of scores for self assertiveness was 7-21, 21 with most self assertiveness. 4. As sexual contacts proceeded, the means of self-esteem and self-assertiveness values decreased. In detail, the respondents having no or light sexual contacts (kiss, putting arms around each other's shoulder, holding a hand) had similar self-esteem values($p{\leq}0.05$). However, ones having relatively intensive sexual contacts (french kiss, touching breast) showed significantly lower self-esteem values($p{\leq}0.05$). Same trend has been obtained for self-assertiveness value. 5. The higher values of self-esteem and self-assertiveness values the respondents had, the later they started the moderate sexual contact (kiss, french kiss) during the dates. Interestingly, among the respondents having intensive sexual contacts (petting genitalia, sexual intercourse) during the dates, those who experienced the such contacts at the first date or later than 10th date have higher self-esteem and self-assertiveness values than one experienced the such contacts during the 2nd$\sim$9th dates, giving U-shape curve. 6. There was a significant relationship between self-esteem and self-assertiveness in girls who have or had boyfriends($P{\leq}.001$). In conclusion, the research shows that self-esteem and self-assertiveness values are significantly related with the sexual contacts of the teenage girls who have or had boyfriends. These results strongly suggest that proper sex education program for teenage girls should contain the program on improving the self-esteem and self-assertiveness. We believe that sex education program is the one of the best ways to prevent the unwanted sexual contacts and pregnancy of teenage girls.

• Journal of Life Science
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• v.18 no.10
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• pp.1455-1463
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• 2008

The purpose of this study was to evaluate the effect of various exercise intensity on Excess post exercise energy expenditure (EPEE), Resting Metabolic Rate (RMR),thyroid hormonal changes and biochemical variables in obese and NIDDM patients. The subject of the present study were divided into four groups and four periods: trained (T; n=10), control (C; n=10), obese (O; n=10) and NIDDM (N; n=10) group. And the periods were divided as follows; Resting (RE), Maximal (MA), High intensity (HI), and Low intensity (LI). There was significant difference in RMR among different intensity of exercise. in the T (p<0.05) not in the C, O, and N groups. however, there was no significant different percent body fat among all groups. In the energy expenditure, there was significant different among C, O, N groups compare to T in HIEE (high intensity exercise energy expenditure), LIEE (low intensity exercise energy expenditure), HIEEPE (high intensity exercise energy expenditure post exercise) and LIEEPE (low intensity exercise expenditure post exercise). In the hormonal level, there was significant different in T4 level in the T group at LI period and there was also significant difference in T4, Free T3, & Free T4 levels in T group at LI period, however there was no significant different in the O and N groups except LI period. In the fatigue variables, there was significant different in lactate and ammonia levels in the N group in the period of HI compare to C. The present cross-sectional study was design to investigate the relationship between exercise intensity and RMR in four groups. The focus of this investigation was to compare RMR in aerobically trained (T), control (C), obese (O) and NIDDM (N) group. The relationship among RMR, exercise intensity and percent body fat would best be investigated using Meta Lyzer 3B, MMX3B and body composition analyzer. Each subject completed measurement of percent body fat, RMR, hormone in the period of maximal oxygen uptake exercise (MA), high intensity exercise (HI), and low intensity exercise (LI). From the results, High and Low intensity of exercise, there was a trend for an increased RMR (kcal/day) in the trained groups and control group (in case of LI) not for the obese and N groups. This is best explained not by the reduced percent body fat but by the highly induced energy expenditure (during exercise and post exercise energy expenditure) and increased T4, Free T3, and Free T4 hormonal levels in the low intensity exercise for the T group and sometimes C group.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.103-128
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• 1997

The object of this study is to evaluate the possibility of chemical-induced liver disorder among workers exposed to various chemicals and to classify the the liver function abnormalities by causes and to analyse the risk factors for each liver disorders. A cross-sectional study including questionnaire survey, physical examination, laboratory tests and ultrasonography of liver was conducted on 1,126 workers, 459 workers in a coal chemical plant(company A) and 667 workers in an insulation material manufacturing factory(company B). An industrial hygienist reviewed the chemicals used in both companies and evaluated the work environments to classify the workers by chemical exposure semiquantitatively. The results are as follows: 1. Of 459 workers in company A, 83 workers(18.1%) are classified as nonexposed, group 163(35,5%) as short-term exposure group, 155(33.8%) as intermediately exposed group and 58(12.6%) as long-term exposed group bared on the mean daily exposure to hepatotoxic chemicals evaluated by an industrial hygienist. Of 667 workers in company B, 484(72.6%) workers were classified as nonexposed and 183(35.5%) as exposed group. 2. Workers with SGOT level higher than 40 IU/l were (10.0%) in company A and 77(11.5%) in company 3, and those with SGPT level higher than 35 IU/l were 118(25.7%) in company A and 198(29.7%) in company B. The differences were not significant between companies and between exposure groups(p>0.05). Workers with $\gamma-GT$ level higher than 62 IU/l were 29(6.3%) in company A and 77(11.5%) in company B (p<0.01). The difference between exposure groups was not significant(p>0.05) within companies. Workers with liver function abnormalities(defined as SGOT higher than 40 IU/l or SGPT higher than 35 IU/l) were 338(30.0%) among 1,126 workers. Of 338 workers with live. function abnormalities 139(12.3%) had fatty liver by ultrasonography, 79(7.0%) had alcoholic liver(defined as workers with liver function abnormalities with weekly alcohol consumption greater than 280 g for more than 5 years), 54(4.8%) had hepatitis B, 12(1.1%) had hepatitis C and the other 114(33.7%) was not otherwise classified. Prevalences of alcoholic liver and fatty liver were significantly lower in company A(prevalence ratio 0.24 for alcoholic liver, p<0.001, prevalence ratio 0.76 for fatty liver, p<0.05) but prevalences of liver disorders between exposure groups within companies were not significant(p>0.05). 3. Summary prevalence ratios(SPR) of live. function abnormalities, fatty live. and other liver disorders, adjusted by age and company were not significantly higher in exposed group in any chemicals(p>0.05) but in some chemicals, SPRs were significantly lower. 4. On simple analysis of risk factors for liver function abnormalities, prevalence odds ratio(POR) of those with age between 30 and 39 was 1.54(p<0.01) and those with age ever 40 was 1.51(p<0.01). POR of those with histories of liver disorders and general anesthesia was 1.77(p<0.001) and 4.02 for those with overweight and 6.23 for those with obesity, defined by body mass index(p<0.001). 5. On logistic regression analysis, risk factors of liver function abnormality were fatty liver(POR 2.92 for grade 1, 12.15 for grade 2), presence of hepatitis B surface antigen(POR 3.62) and obesity(POR 5.38 for overweight and 16.52 for obesity). Presence of hepatitis B surface antigen(POR 0.18) was the only preventive facto. of fatty live. Company(POR 0.30) and obesity(POR 2.49 for overweight, 4.52 for obesity) were related to the alcoholic live. Obesity(POR 2.94 for overweight) was the only significant risk factor of hepatitis B and there was no significant risk factor for liver function abnormality not otherwise classified. It is concluded that the evidence of liver disorder related with chemical exposure is not evident in these factories. It is also postulated that fatty liver and alcoholic liver is most common causes of liver function abnormalities among workers and effort for weight control and improvement of life style should be done.

• Childhood Kidney Diseases
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• v.13 no.2
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• pp.176-188
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• 2009

Purpose : Peritoneal dialysis (PD) is the major form of dialysis in use for infants and children with end-stage renal disease (ESRD). The aim of this study was to gain insight into the current status of children on PD in Korea. Methods : In May 2008, questionnaires were sent to the pediatric nephrologists via e-mail. Four centers replied and those data were reviewed. Results : A total of 103 patients were included in this study. Male to female ratio was 1.6:1. Mean age was $11.5{\pm}4.9$ years (0-19 years). Primary renal diseases diagnosed were as follows: primary glomerular disease (34%), chronic pyelonephritis-reflux nephropathy (14.6%), systemic disease (9.7%), renal hypoplasia/dysplasia (8.7%), heredofamilial disease (6.8%), vascular disease (3.9%), drug-induced nephropathy (1.0%), and unknown (12.6%). PD modalities were as follows: CAPD (42.7%), CCPD (27.2%), NIPD (11.7%), and Hybrid (18.4%). Weekly total Kt/V was $2.1{\pm}0.7$ (0.3-4.1). Results of peritoneal equilibrium test were as follows: low 36.8%, low average 31.6%, high average 19.7%, and high 11.8%. Z-score for weight was $-1.00{\pm}1.20$ (-4.54~+2.50). Z-score for height was $-1.55{\pm}1.65$ (-9.42~+1.87). Growth hormone was administered in 24.3% of patients. Anti-hypertensive drugs were administered in 64.0% of patients. Laboratory findings were as follows: hemoglobin $10.5{\pm}1.4$ g/dL, calcium $9.7{\pm}0.7$ mg/dL, phosphorus $5.4{\pm}1.4$ mg/dL, and parathyroid hormone $324.2{\pm}342.8$ pg/mL. Conclusion : Primary glomerular disease was the most common cause of ESRD. CAPD was the most prevalent PD modality. Low and low average peritoneal transport type were common. Growth disturbance were noted in many patients. Some patients had hypertension even with anti- hypertensive drugs. Calcium-phosphorus levels were maintained adequately, but many patients had secondary hyperparathyroidism.

• Clinical and Experimental Pediatrics
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• v.50 no.9
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• pp.905-911
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• 2007

Purpose : Ghrelin, being secreted from the stomach, stimulates growth hormone secretion and controls energy homeostasis by increasing appetite. Leptin, being secreted from the adipocytes, controls weight and energy homeostasis by decreasing appetite. Leptin concentration is reported to increase after childhood cancer therapy. This study was aimed to compare ghrelin and leptin concentrations in normal children and children who received cancer therapy. Methods : We enrolled forty-three patients who were diagnosed with cancer and received radiotherapy or chemotherapy during Dec. 2004 through Dec. 2005 in St. Marys hospital and Kangnam St. Marys hospital. Forty-five healthy children were selected as a control group whose age, gender, weight and height were similar to those of cancer group. The serum leptin and ghrelin concentrations were also measured by radioimmunoassay. Results : The cancer group showed higher BMI and leptin concentrations. The control group showed higher concentrations of ghrelin. Both control and cancer groups revealed positive correlations between leptin concentrations and BMI. Ghrelin concentrations in the control group showed negative correlations with age, height, weight and BMI but no significant correlation was found in the cancer group. All the parameters in the group treated with chemotherapy only were not different from those in the group treated with chemotherapy and irradiation. But the level of ghrelin in the acute myeloid leukemia group was much higher than those in the acute lymphoblastic leukemia group. Conclusion : Patients with pediatric cancer treatment have presented higher BMI and leptin concentrations but lower ghrelin concentrations than those in healthy children. Because of the relatively short duration and cross sectional method of the study, however, further long term and prospective study will be required in the future.