• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.53-61
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• 2013

Objectives: It is certain that Radioactive iodine thyroid uptake(RAIU) rate should be measured with the standard counts considering the thyroid gland depth in enlarged thyroid patients for the variation from geometric factors. The purpose of this paper is to consider the effects of geometric factors according to detector to source distance and the effective thyroid depth on RAIU rate with experiment test. Materials and Methods: I-131 370 kBq ($10{\mu}Ci$) point source was measured by Captus-3000 thyroid uptake system (Capintec, NJ, USA) with a change Detector-Source Distance from 20 cm to 30 cm at an interval of 1 cm. And we changed the Neck phantom surface-Source Depth in the phantom with 1 cm, 2 cm, 5 cm using the neck phantom in order to reproduce the effective thyroid depth. Results: Every experimental group follows power curve as inverse square curve ($$R2{\geq_-}0.915$$). The average count rates in the case not using a phantom and the every case applied the effective thyroid depth using a phantom was not identical each other. There was significant fluctuations upon the effective thyroid depths applied the effective thyroid depth above 1 cm in $364.4 keV{\pm}10%$ energy ROI (p<0.01). There was not significant difference between the count rates of 1 cm and 2 cm in $364.4keV{\pm}20%$ and $637.1keV{\pm}6.2%$ (p=0.354, p=0.397). In assumed RAIU rate from regression equation, $364.4keV{\pm}20%$ was lower difference than $364.4keV{\pm}10%$ as 6.42% and 5.09% per 1 cm. Every change of count rate upon depth appears decreased line on Linear Regression, but the case of $284.3keV{\pm}10%$ increased only. And also, The graphs of coefficient of variation upon depth increased as straight line on every experimental group. Conclusion: The result appears that application of $364.4keV{\pm}20%$ energy ROI is more suitable for reducing error from the effective thyroid depth. And also, we can estimate the error of 20 cm should be highly reduced than 30 cm for Inverse Square Law. Therefore, If there is not information of the thyroid depth, it is considered that the error from thyroid depth can reduce through set up energy ROIs for $364.4keV{\pm}20%$, and increase Detector-Source Distances.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.17-22
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• 2000

Purpose: This study was conducted to evaluate the association between H. pylori infection and socioeconomic status and to determine the current prevalence of H. pylori infection in Korean adolescents. Methods: A structured questionnaire was sent to the children's parents to obtain demographic information on the parents and environmental information. Of the 532 questionnaires sent out, 375 (70.5%; 170 girls and 205 boys) were returned. Their ages ranged from 10 to 15 years (mean, 12.9 years). After collecting blood samples, we measured serum IgG antibody to H. pylori using ELISA method. The association of risk factors such as age, sex, socioeconomic class, type of house, and crowding index with H. pylori infection were analyzed by multiple regression analysis. Socioeconomic status was estimated from the parents' education and occupation using a modified Hollingshead index. Results: The prevalence rate of H. pylori infection was 16.8% (63/375). It increased with age (10.3% at 10~11 years, 15.9% at 12~13 years, and 20.7% at 14~15 years). The H. pylori infection was inversely related to the socioeconomic class (6.3% for the upper class, 16.0% for the middle class, and 20.0% for the lower calss). Crowding condition and type of house did not affect significantly on seroprevalence of H. pylori infection. After logistic regression, we found that the odds ratio for age was 2.2 (95% confidence interval 0.9~5.4), and for socioeconomic status, 3.6 (95% confidence interval 0.5~28.9). Conclusion: The prevalence of H. pylori infection in Korean adolescents was 16.8%. It related inversely to socioeconomic status but was not statistically significant. Socioeconomic status based on parents' education and occupation seemed to affect more on H. pylori seroprevalence than crowding or type of house did.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.246-253
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• 1994

Four Quercus forests in Mt. Mohu were studied to investigate biomass, net production and effective biomass estimation method. Five $10m{\times}10m$ quadrats were set up, ten sample trees were cut and roots of three sample trees were excavated for dimension analysis in each forest. There was little difference in accuracy among three allometric biomass regression models of logWt=A+BlogD, $logWt=A+BlogD^2H$ and logWt=A+BlogD+ClogH, where Wt, D and H were dry weight, DBH and height, respectively. Analysis of covariance showed that there were no significant differences among slopes and intercepts of allometric biomass regressions, logWt=A+BlogD, of four Quercus species. Biomass of Q. acutissima, Q. nariabilis, Q. serrata and Q. mongolica forests were 164.0, 158.9, 115.3 and 118.9t/ha, respectively. Net production of Q. acutissima, Q. variabilis. Q. serrata and Q. mongolica forests were 25.0, 23.2, 14.5 and 12.6t/ha/yr., respectively. The proportion of roots to total biomass and total net production of Q. mongolica forest was higher than that of three other species forests. Net assimilation ratio of Q. acutissima, Q. variabilis, Q. serrata and Q. mongolica forests were 2.87, 2.80, 3.20 and 2.95, respectively. Relatively less leaf biomass of Q. serrata and Q. mongolica forests were the reason why total biomass and total net production of Q. serrata and Q. mongolica forests were less than those of Q. acutissima and Q. variabilis.

• Clinical and Experimental Pediatrics
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• v.50 no.10
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• pp.970-975
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• 2007

Purpose : Accurate measurement of defect size is important in transcatheter closure of atrial septal defect (ASD). We performed this study to analyze the difference between the measured ASD size and balloon occlusive diameter (BOD) by transthoracic (TTE) or transesophageal echocardiography (TEE). Methods : We investigated 78 patients who underwent transcatheter closure of ASD. The defect size and the distance between the surrounding structures were measured by TTE and TEE. The BOD was measured by TEE during cardiac catheterization. Clinical characteristics and echocardiographic data were compared and analyzed. Results : The difference between BOD and diameter by TTE was $4.8{\pm}3.6mm$ on short axis view, $5.4{\pm}3.2mm$ on long axis view. The difference between BOD and diameter by TEE was $3.6{\pm}2.2mm$ on short axis view, $4.2{\pm}3.1mm$ on long axis view. The difference between BOD and the diameter of defects on TTE, TEE had statistically significant positive correlations with the age of the patients, distance between the, defect and posterior atrial septal wall, the distance between the defect and the mitral valve leaflet, and the diameter of defects and the length of the atrial septum on TTE (P<0.05). Conclusion : BOD of ASD can be estimated by the diameter on TTE and TEE. BOD is expected to measure larger, depending on the size of defects, the distance from surrounding structures and the location of defects on echocardiography. Our data offers important information on details of transcatheter ASD closure which can be helpful in predicting suitability and judging the procedural appropriateness during the procedure.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.4
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• pp.159-174
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• 2017

The purpose of this study was to examine whether the entrepreneurship education through team learning positively influences the effectiveness of team learning and the satisfaction of entrepreneurship curriculum. To do this, we analyzed the questionnaire data of 149 students who took the entrepreneurship course that was conducted by the team learning method focused on problem solving task among the entrepreneurship courses opened in the venture autonomous major. First, we examined the effect of team learning effectiveness and entrepreneurial education satisfaction on the effectiveness of the team learning by individual's intention for startup, diversity of team members, and supporting activities of assistants as independent variables. For this, hierarchical regression analysis was conducted to examine whether independent variables influenced the effectiveness of team learning, and whether the effectiveness of team learning mediates between these independent variables and entrepreneurial education satisfaction. The results of this study support the hypothesis that supporting activities of assistants will influence team learning effectiveness. However, the hypothesis that individual's intention for startup or team diversity influences team learning effectiveness was rejected. On the other hand, the results of the regression analysis show that individual's intention for startup has a significant effect on the satisfaction of entrepreneurship education. In addition, the effectiveness of team learning was found to be influential on the educational satisfaction, and it was verified that the effectiveness of team learning was mediating between the supporting activities of assistants and the satisfaction of entrepreneurship education. Especially, as a result of the hierarchical regression analysis, it was found that the significance of the supporting activities of assistants decreased remarkably. This suggests that the mediating path that affects the satisfaction of entrepreneurship education is very meaningful through the effectiveness of the team learning although the supporting activities of assistants are partially mediated. As a result of this study, it was found that the supporting activities of assistants are important in the team learning entrepreneurship education and it is also confirmed that the individual's intention for startup is also important. Especially, supporting activities of assistants were found to be an important factor affecting the satisfaction of entrepreneurship education through the effectiveness of team learning. Therefore, I think that it is essential to designing a practical education course that meets individual's intention for startup in the entrepreneurship education of university students and networking with the participation of internal and external experts or entrepreneurs. In addition, I think that it is necessary to think more thoughtfulness about the composition of team members in the team learning, and to provide more meticulous support to the effectiveness of the team learning.

• Clinical and Experimental Pediatrics
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• v.51 no.1
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• pp.26-32
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• 2008

Purpose : This study was to provide the methods of developing the growth charts and the blood pressure nomogram among Korean children and adolescents. Methods : The growth charts were developed based on the data from the national growth surveys for children and adolescents in 1998 and 2005. The percentile charts were developed through two stages. At the first stage, the selected empirical charts were smoothed through several fitting procedures including parametric and non-parametric methods. At the second stage, a modified LMS (lambda, mu, sigma) statistical procedure was applied to the smoothed percentile charts. The LMS procedure allowed to estimate any percentile and to calculate standard deviation units and z-scores. The charts for weight-for-age, height-for-age, BMI-for-age, weight-for-height and head circumference-for-age were developed by sex. Age and normalized height controlled sex-specific nomograms of systolic and diastolic blood pressure were developed by a fixed effect model of general regression using the data from 2005 national growth survey. Results : The significant systemic differences between the percentiles of growth charts and the empirical data were not found. The final output of the study is available from Korean Center for Disease Control and Prevention homepage, http://www.cdc.go.kr/webcdc/. Blood Pressure nomogram was tabulated by height percentiles and age using the regression coefficients analyzed with regression model. Conclusion : 2007 growth charts and blood pressure nomogram were the first products based on the statistical modeling using the national survey data. The further study on the methodology including data collection, data cleaning and statistical modeling for representative growth charts would be needed.

• Clinical and Experimental Pediatrics
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• v.50 no.1
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• pp.52-55
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• 2007

Purpose : Hyperbilirubinemia, jaundice and gallbladder hydrops are unusual manifestations of Kawasaki disease (KD). In this case, abdominal pain, anorexia and abdominal distension may follow eventfully. We reviewed the clinical and laboratory data to investigate the causative factors of hyperbilirubinemia in patients with KD. Methods : Two-hundred eighty two children diagnosed and hospitalized with KD were identified by searching patients' charts. Cases were included in the study if diagnosed between January 1997 and December 2004. We reviewed clinical data, age, sex, duration from the onset of fever to admission and duration from start of treatment to defervescence. Clinical and laboratory data were compared between normal (A) and hyperbilirubinemia (B) groups. Results : Thirteen patients (4.6 percent) showed hyperbilirubinemia. In the hyperbilirubinemia group, age and initial ALT value were higher than group A (P=0.003, 0.018 respectively). Duration from the onset of fever to admission and age were relative risk factors in hyperbilirubinemia (P=0.007, 0.003 respectively) in patients with KD. Conclusion : Shorter duration from the onset of fever to admission and older age group were relative risk factors of hyperbilirubinemia in patients with KD.

• Korean Journal of Plant Resources
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• v.9 no.2
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• pp.121-142
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• 1996

This study was to establish the floristic composition and vegetation of resources vascular plants of Mt. Hansuk(1,119.1m; $128^{\circ}15';31'E,\;38^{\circ}02'55'N$). This work was conducted during the period of 1995. Resources vascular plants were composed of 85 families, 229 genera, 370 species, 72 varieties and 10 formae, totaling 452 taxa. Among the investigated resources plants, 15 taxa(2.6%) were Korean endemic species. The forest were comparatively well conserved by Pteridophyta calculation(Pte-Q), 1.34 Useful resources plants were edible source(43.8%), pasture source(38.1%), medicinal source(33.2%), ornamental source(11.9%) and timber source(4.9%) respectively. The forest vegetion was classified into 1 order, 1 alliances and 2 communities; Rhododendro - Quercetalia mongolicae Kim 1990 Lindero - Quercion mongolicae Kim 1990 A. Lespedeza maximowiczii - Quercus mongolica Community B. Carex humilis v. nana - Pinus densiflora Community

• Sleep Medicine and Psychophysiology
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• v.20 no.1
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• pp.22-30
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• 2013

Objectives: Sleep problems has been consistently reported as a suicidal risk factor in adults and, recently, also in adolescents. In this study, dividing study subjects by the previous suicidal behaviors (suicidal vs non-suicidal), we compared the group differences of suicidal risk factors, and examined the possibility of sleep as a suicidal risk factor. Methods: Study subjects were 561 (271 boys and 290 girls) from a community sample of high school students. Suicidal Risk Behavior Checklist, Center for Epidemiological Study-Depression (CES-D), Symptom Checklist-90-Revision (SCL-90-R) Anxiety and Aggression subscale, Pittsburg Sleep Quality Index (PSQI) were done. Results: Forty six students (8.1%) reported previous actual self-harm behavior as a suicidal attempt, 181 students (32.4%) reported having suicidal thought only. Three hundred thirty four students (59.5%) reported no previous suicidal behavior (thought and attempt, both). Suicidal behavior group showed higher score on risk behaviors such as school violence, substance use and internet addiction. CES-D, SCL-90-R, PSQI showed significant group difference. Logistic regression analysis showed suicidal risk were significantly associated with depression, stress in suicidal risk factors and sleep latency, daytime dysfunction in PSQI. Analysis of variance (ANOVA) shows the most prolonged sleep latency and increased index of all PSQI components except sleep efficiency in suicidal attempt group. Conclusions: Sleep Problems had a strong association with the suicidal risk behavior in adolescents. Sleep problems, especially, prolonged sleep latency, daytime dysfunction might be important markers for suicidal behavior. Screening for sleep problems in adolescents are encouraged for the parents, school teachers, and related medical physicians.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.101-109
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• 2020

This study sought to find out the impact of conflicts in social welfare organizations on job performance and to find out the effects of controlling participatory decision-making in their relationships. To that end, a survey was conducted on workers at social welfare centers in Seoul, Gyeonggi Province and Chungcheong Province, and 360 copies were finally used for analysis and Correlation and hierarchical regression and statistical significance analysis of the adjustment effects were performed. As a result, conflicts within the organization, job performance, and participatory decision-making showed a negative correlation, and as participatory decision-making in the relationship between conflict within the organization and job performance showed a controlled effect, the impact of conflicts within the organization on job performance was reduced. These results suggest that participatory decision-making can alleviate conflicts within an organization and at the same time increase job performance. Based on this, the following suggestions were proposed: They include conflict management strategies in the guidelines for social welfare subjects, establish guidelines for conflict management, provide training for workers, engage workers in employee evaluation and compensation system development, and operate permanent organizations such as the Conflict Handling Committee after investigating conflicts within social welfare organizations.