• Clinical and Experimental Pediatrics
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• v.50 no.9
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• pp.862-867
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• 2007

Purpose : The impulse oscillometry (IOS) is applicable to young children because it requires minimal cooperation and a non-invasive method to measure the mechanics of respiratory system. This study aimed to develop the reference values in school-aged children in Korea, using IOS which is a modification of forced oscillation technique (FOT). Methods : Measurements were performed in 92 previously untrained healthy children, aged 7 to 12 years old, using IOS. We analyzed the relationships between the data about their age, height, weight, body surface area (BSA), body mass index (BMI) and the result of IOS using the linear regression test. Results : The success rate of IOS was 92.4%. Stepwise multiple regression of resistance of respiratory system (Rrs) and reactance of respiratory system (Xrs) in natural form for age, height, weight, BSA, BMI showed that height was the most significant predictor and altogether of 5 variables explained the Rrs and Xrs most. Our regression equations at multiple frequencys were comparable to published reference values, especially about the Rrs obtained at 5 Hz. Conclusion : IOS is a feasible method to measure the respiratory resistance in untrained children. We got the reference values using IOS and it seems to be useful to diagnose a variety of respiratory diseases.

• The Korean Journal of Applied Statistics
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• v.30 no.3
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• pp.391-401
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• 2017

This study develops an indicator to manage regional variations of approval rates for long-term care (LTC) service. We used LTC insurance data for grade assessment that include 433,155 applicants from 227 LTC centers across Korea in 2015. The approval rate for each center was defined as the proportion of the numbers of approved applicants out of all applicants. We assumed that the approval rates depended on the characteristics of applicants. We estimated the 'standard' approval rates from a multiple linear regression analysis using the characteristics of applicants as independent variables. The difference between the observed and the standard rates was then defined as an indicator for deviation. A center having a large difference could be considered as a center with a potential error in grade assessment. We also examined if the characteristics of investigators affected the approval rates. We found that the socio-demographic characteristics of applicants and reapplication rate for LTC grade were independent factors affecting the approval rates. Centers having the management indicator values falling outside the middle 95% of the distribution were identified as centers with an error in grading. We expect that this study will contribute to enhancing reliability and equity in LTC grading.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.227-234
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• 2010

To see the influence of bird species by the change of temperature in city, we have carried out bird census 22 times for 6 years from 2003 to 2008 in Worldcup Park, Seoul. And we analysed the correlation between the temperature of Seoul and wildbirds. 15 orders, 38 families and 102 species were confirmed to have existed. We could find that Hypsipetes amaurotis gradually turned out to have increased with statistical significance for 6 years. To analyze the relationship between the temperature of Seoul and wildbirds, we have chosen 31 bird species observed more than 30% in frequency and proceeded the regression analysis. The survey shows that with the temperature rise the number of the resident birds such as Pica pica, Parus palustris, Anas platyrhynchos and Anas poecilorhyncha and the migratory birds such as Buteo buteo has declined. These 5 species have a possibility to be decreased as a global climate warming and maybe move to another habitat. In contrast, Oriolus chinensis and Falco tinnunculus are characterized into the species that increased due to the rising temperature. So they have a posibility to increase and expand their habitat. This survey shows that temperature rise can cause to change the composition of bird species. And 7 bird species related with the change of temperature have a great possibility as a indicator of the climate change.

• Sleep Medicine and Psychophysiology
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• v.24 no.2
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• pp.97-105
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• 2017

Objectives: To evaluate sleep characteristics and factors associated with sleep disturbance in schizophrenia patients with concurrent active psychotic symptoms and insomnia. Methods: Schizophrenia patients with insomnia and active psychotic symptoms (n = 63) were recruited from community-based mental rehabilitative facilities. Sleep scales such as the Korean version of the Insomnia Severity Index (ISI-K) and the Korean Version of the Pittsburgh Sleep Quality Index (PSQI-K) were evaluated and those with ISI-K >15 were included in the study. Psychotic, anxiety and depressive symptoms were rated with the Brief Psychotic Rating Scale (BPRS), the Korean Version of the Anxiety Sensitivity Index (K-ASI), and the Korean Version of the Beck Depression Inventory-I (K-BDI), respectively. Pearson correlation analyses were performed between the sociodemographic data, ISI-K and PSQI-K. Multiple linear regression analysis was conducted to investigate the factors which affected the ISI-K and PSQI-K. Results: The mean ISI-K and PSQI-K scores were $18.1{\pm}2.6$ and $12.0{\pm}2.2$, respectively. Pearson correlation analysis showed a negative correlation between age of onset and ISI-K score and positive correlations between BRPS and PSQI-K scores and between K-ASI and both ISI-K and PSQI-K scores. Multiple regression analyses for both ISI-K and PSQI-K with K-ASI, age of onset, and BPRS as covariates revealed K-ASI as the only significant remaining factor. Conclusion: Our study suggests that anxiety symptoms are associated with insomnia symptoms in schizophrenia patients regardless of depressive or psychotic symptoms.

• Clinical and Experimental Pediatrics
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• v.46 no.1
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• pp.51-55
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• 2003

Purpose : We intended to find out the role of transesophageal atrial pacing in evaluation of infants and children with palpitation of unknown origin. Methods : We tried transesophageal atrial pacing study in 69 infants and children with palpitation, in whom tachycardia wasn't documented in electrocardiogram and reviewed retrospectively the records of transesophageal pacing and medical records of theses patients to find out the induction rate of tachycardia by transesophageal atrial pacing and the possible mechanism of tachycardia if induced. Results : In 70.1% infants and children with palpitation, tachycardia was induced, so we could conclude that tachycaridia was the cause of palpitation in these cases. In most cases, tachycardia was induced by rapid atrial pacing, and in 21% by using isoproterenol. Tachycardia induction rate was higher in <6-year-old children than ${\geq}6$-year-old children(P<0.05). In cases of the induced, we reviewed the mechanism of tachycardia. Of these induced tachycardias, 53.2% is atrioventricular reentry tachycardia, 34.0% were atrioventricular nodal reentry tachycardia, and 12.8% were idiopathic left ventricular tachycardia. Invasive electrophysiologic study was done to 10 patients of those induced. The results of electrophysiologic study and transesophageal pacing and recording were the same except for one patient. Conclusion : Transesophageal atrial pacing and recording is a less invasive, safe and useful method to find out the cause of palpitation and the mechanism of tachycardia in infants and children.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.456-462
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• 2015

365 pieces of domestic $38{\times}140{\times}3600mm$ Red pine structural lumber were machine graded conforming to a softwood structural lumber standard (KS F 3020). The allowable bending stresses calculated for each grade were compared with the values currently tabulated in the standard. Four calculation methods for lower $5^{th}$ percentile bending stress were non-parametric estimation with 75% confidence level, 2-parameter and 3-parameter Weibull distribution fit, and bending modulus of rupture (MOR)-modulus of elasticity (MOE) regression based method. Only the data set of Grades E8, E9, and E10 were statistically eligible for the $5^{th}$ percentile calculation. The MOR-MOE regression based method only was able to estimate the lower $5^{th}$ percentile values theoretically for the full range of grades. The results showed that all allowable bending stresses calculated were lower than the design values tabulated in the standard. This implies that the current machine grading system has the pitfall of structural safety. Improvement in current machine grading system could be achieved by introducing the bending strength and stiffness combination grade system.

• Fire Science and Engineering
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• v.32 no.5
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• pp.112-121
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• 2018

In the present study, a group of subjects consisting of "Fire Professional Engineers" was selected to examine the effects of life safety awareness and safety behaviors of the subjects on life safety through an analyses of the descriptive statistics, factors, reliability, and correlation; simple regression and three-stage regression analyses on mediation were also carried out based on the hypotheses developed. The results showed that the degree of safety behavior increased by 72.1% in accordance with the increased safety awareness of fire professional engineers; the life safety was also increased by 61.5% and 64.5% by the increases in safety awareness and safety behavior of fire professional engineers, respectively. In addition, the safety behaviors demonstrated a partial mediatory effect in the relationship between safety awareness and life safety. All hypotheses (H1, H2, H3, H4), established for the present study, were accepted based on statistical verifications that justified an amendment of the Acts pertinent to firefighting service focusing on life safety; the data are expected to be exploited to reflect significance of life safety.

• Sleep Medicine and Psychophysiology
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• v.13 no.2
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• pp.59-66
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• 2006

The objective of this study was to investigate the relationship between insomnia severity, depression, anxiety, and anxiety sensitivity and to find out the explanatory variables that account for the insomnia severity among depression, anxiety, and anxiety sensitivity in general population. 95 mentally healthy volunteers who visit health promotion center of Kangbuk Samsung hospital for their regular medical examination were requested to complete Athens Insomnia Scale, Beck Depression Inventory, State-Trait Anxiety Inventory, and Anxiety Sensitivity Index. Association between total scores of Athens Insomnia Scale and other variables (total scores of Beck Depression Inventory excluded item 16, total scores of State Anxiety, total scores of Trait Anxiety, and total scores of Anxiety Sensitivity Scale) was assessed individually with partial correlations adjusted by age and then together using multiple regression analysis. The total scores of Athens Insomnia Scale were significantly associated with total scores of Beck Depression Inventory excluded item 16 (r=0.541, p<0.001), total scores of Trait Anxiety (r=0.642, p<0.001), total scores of State Anxiety (r=0.267, p<0.05), and total scores of Anxiety Sensitivity Index (r=0.312, p<0.01). Total scores of trait anxiety showed the highest correlation with the total scores of Athens Insomnia Scale and was the significant predictor to total scores of Athens Insomnia Scale among the other predictor variables (p<0.001). These results show that insomnia severity is positively correlated with depression, anxiety, and anxiety sensitivity. The correlation was strongest with trait anxiety. In addition, our results suggest that trait anxiety is associated with insomnia severity in general populations.

• The Journal of Bigdata
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• v.6 no.1
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• pp.91-113
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• 2021

Despite the influence of real estate in the Korean asset market, it is not easy to predict market trends, and among them, apartments are not easy to predict because they are both residential spaces and contain investment properties. Factors affecting apartment prices vary and regional characteristics should also be considered. This study was conducted to compare the factors and characteristics that affect apartment prices in Seoul as a whole, 3 Gangnam districts, Nowon, Dobong, Gangbuk, Geumcheon, Gwanak and Guro districts and to understand the possibility of price prediction based on this. The analysis used machine learning algorithms such as neural networks, CHAID, linear regression, and random forests. The most important factor affecting the average selling price of all apartments in Seoul was the government's policy element, and easing policies such as easing transaction regulations and easing financial regulations were highly influential. In the case of the three Gangnam districts, the policy influence was low, and in the case of Gangnam-gu District, housing supply was the most important factor. On the other hand, 6 mid-lower-level districts saw government policies act as important variables and were commonly influenced by financial regulatory policies.

• Journal of Science Education
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• v.47 no.1
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• pp.63-74
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• 2023

This study aims to investigate the effects of pre-service elementary teachers' scientific self-efficacy by science motivation according to the academic track in high school. The subjects of this study were 525 pre-service elementary teachers of which 350 pre-service elementary teachers were selected from the humanities and social sciences track in high school and 175 pre-service elementary teachers were selected from the science-engineering track in high school. In order to investigate the difference between scientific self-efficacy and science motivation among pre-service elementary teachers, Independent sample t-test and Cohen's d were done. In order to find out about the Influencing of scientific self-efficacy on science motivation, multiple regression analysis was used. The results of this study were as follows: First, there were statistically significant differences in scientific self-efficacy and science motivation, and the average of pre-service elementary teachers who selected science-engineering were significantly higher. Second, explanation power of scientific self-efficacy on science motivation appeared as 66.7~68.3%. The explanatory power of pre-service elementary teachers' who selected humanities and social sciences were higher. The relative importance was high in task difficulty preference factor to humanities and social sciences, was high in self-regulation efficacy to science-engineering. In conclusion, in order for pre-service elementary teachers to achieve high achievement and motivation in science subjects, and to teach science well to students in the school field, teacher education that can improve scientific self-efficacy should be conducted.