• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.4
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• pp.359-367
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• 2020

The aim of this study was to identify the association between candidiasis and early childhood caries and to investigate whether the experience of candidiasis or oral candidiasis before age 1 can be considered as a risk factor for early childhood caries. The database used in this study was provided by Health Insurance Review and Assessment Service. Medical records of children born from January 2010 to December 2012 were obtained, and those without dental records were excluded. Subjects were divided into several groups based on the experience of candidiasis or oral candidiasis before age 6: candidiasis group and non-candidiasis group; oral candidiasis group and non-oral candidiasis group. Another categorization was done according to the experience of candidiasis or oral candidiasis before age 1. The incidence rate of early childhood caries in each group were compared. The prevalence of dental caries in children who have been diagnosed with candidiasis or oral candidiasis before age 6 was significantly different from those who have not experienced candidiasis. Similarly, children who have suffered from candidiasis or oral candidiasis before age 1 had significantly different incidence of caries from the children without candidiasis experience.

• Journal of radiological science and technology
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• v.33 no.3
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• pp.231-237
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• 2010

Computed tomography (CT) has been established as an important diagnostic tool in clinical medicine and has become a major source of medical exposure. A nationwide survey regarding CT examinations was carried out in 2007. Thanks to the appeasement policy regulating the import of CT scanners, there are 1,825 CT scanners across the country as of the end of March 2010, which means that we have 36.8 CT scanners per one million people. The annual number of examinations was 3.29 million, the number of examinations per 1000 population was 68. The most part of examinations was abdomen and pelvis. and the collective effective dose was in these parts. The effective dose per one population was evaluated as 0.952 mSv.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.11
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• pp.7990-8000
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• 2015

Plant factories are plant cultivation systems which produce farm products uniformly under the controlled environmental condition regardless of seasons and places. Thermal flow in the plant factory is an important parameter in cultivating plants. In this research, we study thermal flow characteristics for a hybrid plant factory with multi-layer cultivation shelves using computer simulation techniques. In order to obtain numerical solutions for thermal flow characteristics, a finite volume method was applied. We consider a low-Reynolds-number ${\kappa}-{\epsilon}$ turbulence model, incompressible viscous flows, and pressure boundary conditions for numerical simulation. Commercial software Solid Works Flow Simulation is then used to investigate characteristics of thermal flows in the plant factory applying several different inflow air velocities and arrangements of cultivation shelves. From numerical analysis results, we found that temperatures in cultivation shelves were uniformly distributed for Case 3 when the inflow air velocity was 1.6 m/s by using a blower in the plant factory. However in Case 1 lower temperature distributions were observed in test beds, TB2 and TB3, which indicated that additional temperature control efforts would be required. Average shelf temperature increased by $3^{\circ}C$ using artificial light source (DYLED47) with 50% blue and 50% red LED ratios. Korea Academia-Industrial cooperation Society.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.484-492
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• 2018

This study examined the effects of field complexity and type of target objects on the performance in baggage screening task. A total of 62 participants(male: 45.2%, female: 54.8%) participated and their mean age was 22.88. The simulated baggage screening task was developed for this study and after the orientation and task exercises, main experiment session was conducted. Participants performed a total of 200 tasks and 40(20%) contained target object. The complexity was set at three levels: high, middle, and low levels and the number of background items contained 20, 14. and 8 respectively. The type of target was set as gun, knife, liquid, and righter. The dependent variables were hit ratio and reaction time. The results showed that the hit ratio decreased and reaction time increased significantly as field complexity increased, and they varied depending on the type of target. The hit ratio of the knife was the highest and liquid lowest and reaction time of the knife was the fastest and liquid slowest. In addition, the interaction effect was also significant. Knife was not affected by complexity, however, small item such as lighter was most affected by complexity.

• The Journal of Society for e-Business Studies
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• v.23 no.3
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• pp.207-224
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• 2018

In this article, an empirical study was conducted by using public dataset from Lending Club Corporation, the largest online peer-to-peer (P2P) lending in the world. We explore significant predictor variables related to P2P lending default that housing situation, length of employment, average current balance, debt-to-income ratio, loan amount, loan purpose, interest rate, public records, number of finance trades, total credit/credit limit, number of delinquent accounts, number of mortgage accounts, and number of bank card accounts are significant factors to loan funded successful on Lending Club platform. We developed online P2P lending default prediction models using discriminant analysis, logistic regression, neural networks, and decision trees (i.e., CART and C5.0) in order to predict P2P loan default. To verify the feasibility and effectiveness of P2P lending default prediction models, borrower loan data and credit data used in this study. Empirical results indicated that neural networks outperforms other classifiers such as discriminant analysis, logistic regression, CART, and C5.0. Neural networks always outperforms other classifiers in P2P loan default prediction.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.2
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• pp.229-238
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• 2023

The objective of this study was to investigate trends in ankyloglossia and its surgical treatment among pediatric patients in South Korea from 2011 to 2020. Data from Health Insurance Review and Assessment Service (HIRA)'s Healthcare Bigdata Hub were used for analysis of the ankyloglossia diagnosis rate and frenum surgery rate. Considering annual population change, crude rates per 100,000 were calculated and analyzed. To investigate other factors of frenum surgery incidence besides gender and age, pediatric patient sample data from HIRA were used. The diagnosis rate of ankyloglossia increased from 204.4 in 2011 to 356.6 per 100,000 people in 2020, while the frenum surgery rate increased from 26.8 to 34.3 per 100,000 people. Males were more likely to receive frenum surgery than females. Surgeries were more likely to be done at a hospital instead of a clinic or a general hospital. In the age group of 0 - 4 years, the largest number of frenum surgeries were performed in pediatrics, and in the age group of 5 - 9 years, the largest number of surgeries were conducted in pediatric dentistry. In the older age groups, the largest proportion of frenum surgeries were performed in the departments of conservative dentistry and oral and maxillofacial surgery. The diagnosis of ankyloglossia and the operation of frenum surgery among South Korean children increased during the last decade. Since the function of the tongue can affect maxillofacial development in many aspects, pediatric dentists should pay more attention to the functional management of intraoral soft tissue in growing children.

• Journal of Korean Elementary Science Education
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• v.42 no.1
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• pp.93-108
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• 2023

This study aims to analyze the types and roles of visualization materials presented in the third- and fourth-grade national and authorized science textbooks based on the 2015 revised curriculum. Using the type and role framework, 17 chapters were analyzed. The analysis revealed, first, that the national and authorized textbooks had different total amounts of visualization data and total amounts of simple illustrations. However, no difference in the amounts of simple illustrations and infographics used in the units was evident. The units that used the most infographics were Life, Earth and Universe, in that order, in both the national and the authorized textbooks. Second, simple illustrations were observed to have role differences according to the type of visualization data, but infographics had no such differences. Specifically, the motivational role in a simple illustration increased in all the authorized textbooks. Third, looking at the frequencies of the infographic subtypes, the Process, Structure, Comparative Analysis, and Timeline types accounted for 86% of the total, but the proportions of those subtypes varied in the national and authorized textbooks. Based on the results of this study, I suggest that to achieve differentiation in the types or roles of visualization materials, changes in the types, processes, and skills of inquiry must first occur, as must changes in the structure of chapters or lessons. Continuous research and discussion on the standards and methods for authorized textbooks are also needed.

• Neonatal Medicine
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• v.18 no.1
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• pp.70-75
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• 2011

Purpose: Recently, the incidence of preterm and low birth weight infants (LBWI) is increasing, even though the birth rate is continuously low in Korea. Despite that change, there continues to be a deficit of beds in the neonatal intensive care unit (NICU). This study is based on the 2009 Korean Statistical Information Service that examined the development of a Korean NICU service and the survival rate of preterm infants by regionally analyzing the rate of total live births, preterm infants, LBWI, and NICU beds in Korea. Methods: Data were obtained from the Korean Health Insurance Review and Assessment Service and Korean Statistical Information Service. We confirmed the regional total live birth rate, number of LBWI, and preterm infants and NICU numbers, and all of the results were compared to the average value to determine deficient areas of NICU beds. Results: There were 25,374 (5.7%) preterm infants and 21,954 (4.9%) LBWI in the total number of live births (444,849) in 2009, and regions of high proportion compared to the mean value were Busan, Daegu, and Ulsan. Total NICU beds totaled 1,284, and regions of high rates preterm infants and LBWI per 1 NICU bed compared to the mean value were Incheon, Daegu, Ulsan, etc. The NICU holding rate was 87.5% (1,284/1,468), which was increased from 2005. However, there were still shortages of 184 NICU beds (12.5%), especially in Gyeonggi-do, which lacked 157 beds. Conclusion: High risk neonates difficult to transfer, and they need immediate and continuous treatment. As a result, a foundation of well-balanced, national NICU regionalization is necessary. This study suggested that more NICU facilities must be implemented, and clinicians should realize the continuing deficiency of NICU beds in cities and provinces.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.707-718
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• 2019

Ecklonia cava Kjellman, which has recently gained popularity due to the spread of farming techniques, is expected to be developed in various varieties in the future. There exist increased needs for research on the basis of natural populations and inter-regional morphological variations. We compared the morphology of the aquaculture and natural populations from 16 coastal areas in Korea. The 18 traits found suitable for distinguishing varieties were selected from 14 measurement traits and 4 ratios related to the main morphology and characteristics of primary blade, secondary blade, and stipe. In the cluster analysis, Janggil (E4) and Sorok (S7) showed significant differences from those of the same coastal region. Two groups, including Suyou (Q6, Q8, and Q10) which was the second year of farming, of the rest of the populations from East sea and southern coast were distinguished. Three populations of Jeju were divided into a regional group. In the principal component analysis (PCA), a large number of populations from East sea and Southern coast appeared in the center with aquaculture populations. PC1 and PC2 associated with traits of secondary blade index, stipe length and diameter, stipe length/primary blade length, primary blade length and width, secondary blade number, secondary blade length and width, divided E4, S7 and populations of Jeju region. As a result, the 18 characters of this study were found to be useful as criteria for discrimination of populations with significant differences in each coastal region, and these populations were expected to be candidates for new varieties.

• Journal of the korean academy of Pediatric Dentistry
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• v.50 no.3
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• pp.360-372
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• 2023

The aim of this study was to identify the current state of pediatric dentists, evaluate the adequacy of pediatric dentist supply and demand, and find out the perception of all pediatric dentists on the current state of pediatric dentists and policy establishment. An Online survey was conducted among pediatric dentists. The questionnaire was subdivided into 'general characteristics', 'number of dental treatments and working days per year', 'proportion of covered services', 'perceptions of supply and demand of pediatric dentists'. Through the Korean Academy of Pediatric Dentistry, the Health Insurance Review and Assessment Services, the National Health Insurance Service (NHIS), and the Korean Statistical Information Service, the current state of pediatric dentists, the number of claims for covered services, and the decrease in births per year were investigated. Dental clinics claiming to be pediatric dentistry reached half of all medical institutions, but only 3.78% of pediatric dentists actually worked. 61.36% of all pediatric dentists were concentrated in the metropolitan area, showing a national imbalance. Although the population of children and adolescents have continuously decreased over the past 20 years, the number of NHIS-covered services has shown a continuous increase. Over the past 10 years, the optimal supply of pediatric dentists has been maintained at around 4,000. According to the analysis, 92.15% of pediatric dentists thought that it was necessary to prepare policies and support measures at the government level. This study is expected to be used as basic data for establishing a demand estimation method for pediatric dentistry specialists in the future.