• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.649-656
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• 2006

The purpose of study is to measure soil erosion quantity for elapsed four years from the fire on forest fired sites of Dong-gu, Daegu. This study was conducted to investigate the characteristics of soil erosion by fire occurrence influencing on the soil erosion were. Also analysis result follows that the relations between soil erosion quantity and rainfall intensity, the slope and elapsed year. The results analysed were as follows: 1. Soil erosion by year of occurrence of forest fire was increased 1.9 to 5.7 times as rainfall intensity was increased by 30 m/hr, and 1.4 to 14.2% as degree of slope was increased by $10^{\circ}$. 2. In the first year of forest fire occurrence, soil erosion was fairly heavy for 10 minutes of initial rainfall of which rainfall intensity was 80 m/hr and degree of slope was $30^{\circ}$. The amount of soil erosion was gradually reduced as elapsed time. From two years after fire, the amount of soil erosion by rainfall intensity and degree of slope was nearly constant. 3. The amount of soil erosion by rainfall intensity and slope in accordance with elapsed time after fire was reduced 28.9 to 94.1% in three years after occurrence of forest fire as compared to the first year of fire. Soil erosion was fairly heavy by rainfall intensity and slope in the first year of fire, but it was gradually reduced from two years after fire. 4. In the analysis on influences of each factors on the amount of soil erosion on forest fired sites, the amount of soil erosion was significant differences in major impacts of each rainfall intensity, degree of slope and elapsed year after fire and interaction of rainfall intensity${\times}$degree of slope and rainfall intensity${\times}$elapsed year after fire, but no differences were observed in interaction of degree of slope${\times}$elapsed year after fire and rainfall intensity${\times}$degree of slope${\times}$elapsed year after fire. Rainfall intensity was the most affecting factor on the amount of soil erosion and followed by degree of slope and elapsed year after fire. 5. For correlation between soil erosion and affecting three factors, soil erosion showed significant positive relation with rainfall intensity and degree of slope at I % level, and significant negative relation with elapsed year after fire at 1 % level. 6. As a result of regression of affecting three factors on soil erosion. rainfall intensity was most significant impact factor in explaining the amount of soil erosion on forest fired sites, followed by degree of slope and elapsed year after forest fire. 7. The formula for estimating soil erosion using rainfall intensity, degree of slope and elapsed year after forest fire occurrence was made. S.E = 0.092R.I + 0.211D.S - 0.942E.Y(S.E : Soil erosion, R.I : Rainfall intensity, D.S : Degree of slope, E.Y : Elapsed year after forest fire occurrence)

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.97-121
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• 2013

With the growing importance of knowledge for sustainable competitive advantages and innovation in a volatile environment, many researches on knowledge sharing have been conducted. However, previous researches have mostly relied on the questionnaire survey which has inherent perceptive errors of respondents. The current research has drawn the relationship among primary participant behaviors towards the participation level in knowledge sharing, basically from online user behaviors on Wikipedia, a representative community for online knowledge collaboration. Without users' participation in knowledge sharing, knowledge collaboration for creating knowledge cannot be successful. By the way, the editing patterns of Wikipedia users are diverse, resulting in different revisiting periods for the same number of edits, and thus varying results of shared knowledge. Therefore, we illuminated the participation level of knowledge sharing from two different angles of number of edits and revisiting period. The behavioral dimensions affecting the level of participation in knowledge sharing includes the article talk for public discussion and user talk for private messaging, and community registration, which are observable on Wiki platform. Public discussion is being progressed on article talk pages arranged for exchanging ideas about each article topic. An article talk page is often divided into several sections which mainly address specific type of issues raised during the article development procedure. From the diverse opinions about the relatively trivial things such as what text, link, or images should be added or removed and how they should be restructured to the profound professional insights are shared, negotiated, and improved over the course of discussion. Wikipedia also provides personal user talk pages as a private messaging tool. On these pages, diverse personal messages such as casual greetings, stories about activities on Wikipedia, and ordinary affairs of life are exchanged. If anyone wants to communicate with another person, he or she visits the person's user talk page and leaves a message. Wikipedia articles are assessed according to seven quality grades, of which the featured article level is the highest. The dataset includes participants' behavioral data related with 2,978 articles, which have reached the featured article level, with editing histories of articles, their article talk histories, and user talk histories extracted from user talk pages for each article. The time period for analysis is from the initiation of articles until their promotion to the featured article level. The number of edits represents the total number of participation in the editing of an article, and the revisiting period is the time difference between the first and last edits. At first, the participation levels of each user category classified according to behavioral dimensions have been analyzed and compared. And then, robust regressions have been conducted on the relationships among independent variables reflecting the degree of behavioral characteristics and the dependent variable representing the participation level. Especially, through adopting a motivational theory adequate for online environment in setting up research hypotheses, this work suggests a theoretical framework for the participation level of online knowledge sharing. Consequently, this work reached the following practical behavioral results besides some theoretical implications. First, both public discussion and private messaging positively affect the participation level in knowledge sharing. Second, public discussion exerts greater influence than private messaging on the participation level. Third, a synergy effect of public discussion and private messaging on the number of edits was found, whereas a pretty weak negative interaction effect of them on the revisiting period was observed. Fourth, community registration has a significant impact on the revisiting period, whereas being insignificant on the number of edits. Fifth, when it comes to the relation generated from private messaging, the frequency or depth of relation is shown to be more critical than the scope of relation for the participation level.

• KDI Journal of Economic Policy
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• v.30 no.2
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• pp.99-128
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• 2008

Nearly all Koreans are insured through National Health Insurance(NHI). While NHI coverage is nearly universal, it is not complete. Coverage is largely limited to minimal level of hospital and physician expenses, and copayments are required in each case. As a result, Korea's public insurance system covers roughly 50% of overall individual health expenditures, and the remaining 50% consists of copayments for basic services, spending on services that are either not covered or poorly covered by the public system. In response to these gaps in the public system, 64% of the Korean population has supplemental private health insurance. Expansion of private health insurance raises negative externality issue. Like public financing schemes in other countries, the Korean system imposes cost-sharing on patients as a strategy for controlling utilization. Because most insurance policies reimburse patients for their out-of-pocket payments, supplemental insurance is likely to negate the impact of the policy, raising both total and public sector health spending. So far, most empirical analysis of supplemental health insurance to date has focused on the US Medigap programme. It is found that those with supplements apparently consume more health care. Two reasons for higher health care consumption by those with supplements suggest themselves. One is the moral hazard effect: by eliminating copayments and deductibles, supplements reduce the marginal price of care and induce additional consumption. The other explanation is that supplements are purchased by those who anticipate high health expenditures - adverse effect. The main issue addressed has been the separation of the moral hazard effect from the adverse selection one. The general conclusion is that the evidence on adverse selection based on observable variables is mixed. This article investigates the extent to which private supplementary insurance affect use of health care services by public health insurance enrollees, using Korean administrative data and private supplements related data collected through all relevant private insurance companies. I applied a multivariate two-part model to analyze the effects of various types of supplements on the likelihood and level of public health insurance spending and estimated marginal effects of supplements. Separate models were estimated for inpatients and outpatients in public insurance spending. The first part of the model estimated the likelihood of positive spending using probit regression, and the second part estimated the log of spending for those with positive spending. Use of a detailed information of individuals' public health insurance from administration data and of private insurance status from insurance companies made it possible to control for health status, the types of supplemental insurance owned by theses individuals, and other factors that explain spending variations across supplemental insurance categories in isolating the effects of supplemental insurance. Data from 2004 to 2006 were used, and this study found that private insurance increased the probability of a physician visit by less than 1 percent and a hospital admission by about 1 percent. However, supplemental insurance was not found to be associated with a bigger health care service utilization. Two-part models of health care utilization and expenditures showed that those without supplemental insurance had higher inpatient and outpatient expenditures than those with supplements, even after controlling for observable differences.

• Journal of Service Research and Studies
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• v.9 no.3
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• pp.39-60
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• 2019

The purpose of this study is to analyze the determinants of insurance product cross selling performance. For the study, 11 insurance managers and 2 sales managers belonging to A insurance agency were selected and in-depth interviews were conducted. The analysis of the research data was done by the open coding method suggested by Strauss & Corbin(2001). As a result, 84 concepts, 28 subcategories and 10 categories were derived. The ten categories that were determinants of insurance product cross-selling performance were personal characteristics, consultation method, cross-selling ratio, sales culture, education, customer change, customer DB provision, satisfaction, business support system, and customer service. In order to verify the qualitative results, quantitative analysis was emplyed to the actual performance data of insurance planners belonging to A insurance agency during April 2016~March 2019. As a result of the analysis, the age, position, and the number of months worked in the insurance company had a statistically significant effect on the number of life insurance contracts in total insurance contracts and life insurance contracts in total insurance contracts. In addition, the age, position, and the number of months worked in the insurance company had a statistically significant negative impact on the number of non-life insurance contracts in the total number of insurance contracts and the total amount of insurance contracts in total insurance contracts. The result of this study can be an important basic data for the development of educational programs and job support systems for the training of insurance planners. Insurance companies should refer to ten categories derived from qualitative research in order to increase the performance of insurance planners and to promote long-term service. Especially, it is necessary to develop specialized education programs and job support systems so that cross sales that increase the proportion of life insurance sales increase.

• Journal of dental hygiene science
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• v.16 no.1
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• pp.26-36
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• 2016

The purpose of this study was to examine how oral health literacy of mothers affect the oral health status of their preschool children. The subjects were 233 mothers and their preschool children who are between 5 and 6 years old. They were selected according to the convenience sampling method. The individual self-administered questionnaire was used for the mother's survey while the children were interviewed using structured questionnaire to examine their oral health status and behavior. According to study results, the number of decayed primary teeth and the number of decayed and filled primary teeth had a statistically significant negative correlation with the oral health literacy of the mother, the children's oral health knowledge, attitude and behavior (COHKAB), and the mother's oral health management behavior. Hierarchical multiple regression analysis was performed after including general characteristics variables, the COHKAB and the mother's oral health management behavior. Meanwhile, mother's oral health literacy had a statistically influence on children's oral health status. The higher the mother's oral health literacy level, the lower the number of decayed and filled primary teeth were. The findings suggest that efforts to improve the oral health status of preschool children should consider mother's oral health literacy as an important factor. Therefore, the effective intervention and education programs are necessary to enhance mother's oral health literacy.

• Journal of dental hygiene science
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• v.9 no.4
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• pp.453-459
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• 2009

The purposes of this research were to evaluate the relationships of between characteristics of noise and annoyance of dental hygienist by noise in dental clinic. To investigate the dental clinic workers' reactions to noise when occurred in dental clinic, the noise level test in dental clinic and questionnaire were taken. As a result of noise evaluation, It shows that the range of noise level was 67.7~78.3dB(A) and frequency was very high (more than 4KHz). It's seem to be begins occurrence of stamina-loss, contraction of peripheral blood vessel, decrease of adrenocortical hormones. Most of respondents were affected by noise: 67% of respondents were nervous about noise and the rest of respondents were bearable. Analysis by NR-curve showed that it was exceed the noise permit level in working space. As a result of correlation - test, the more exposed dental hygienist to noise, the more felt the unpleasantness and fatigue. It's hard to sufficient explanation to patients about the dental treatment. So it's thoughts that insufficient explanation will negative impact on the patients' satisfaction and increase competitiveness in dental clinics. To remedy a unpleasantness and fatigue of noise in dental hygienist, it's considered that making an offer the ear protection and choosing the low noise-vib. equipment and using the masking effect. Therefore, It can be provide a pleasant working environment with dental hygienist and It will have a great advantage to dental clinics to improve their competitiveness.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.747-761
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• 2017

The purpose of this study is to analyze differences in the teaching practices of biology teachers according to their awareness of the importance of evolution. For this purpose, two teachers who experienced study of evolution and recognized its importance, along with two teachers with no experience in evolution education in the comparison group, were included in the sample. To observe teaching practices, two classes each on biological evolution and non-evolution were selected, recorded and transcribed. The content analyzed included the teachers' view on evolution education and teachers' evolution concepts reflected in teaching practice. As a result, the level of understanding of the teachers' evolution concept was unrelated to teachers' awareness of the importance of evolution. Instead, each teacher would not feel the need for religious beliefs or awareness of the importance of evolution to have a negative impact on the awareness of the importance of evolution. Inexperienced teachers tend to reject the retraining opportunities to recognize the importance of evolution. In addition, inexperienced teachers were only superficially aware of the evaluation and improvement of evolution presented in textbooks and curricula. In actual teaching practice analysis, inexperienced teachers' utilizing ratio of the evolution key concept was higher than that of experienced teachers. Only experienced teachers were aware of the misconceptions presented in their execution and described the causes that appear in these misconceptions. Teachers who recognized the importance of evolution were widely using the key concepts of evolution, as well as more practical in preventing the misconceptions related to evolution forms. It indicates that biology teachers who do not realize the importance of evolution in biology education need to experience explicit and practical education programs as well as instructional materials on evolution.

• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.183-198
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• 1997

This case study was conducted by verification the site characteristics based on the questionnaire and interview obtained from the all factories located at No. 1 developing area in Kumi industrial complex. The site characteristics were presumed from the process of location behavior and spatial linkage. Kumi industrial complex was developed to improve export industry at national levels by providing chief land price and benefiting various tax. Kumi industrial complex which enticed many factories is playing an important role in export industry in Korea. At beginning, the detention of large enterprises promoted the establishment of related small to medium sized factories into the complex. Two distinctive industries. textile and electronic, were reflected by the purpose to establish the complex and industrial characteristics of Taegu city. respectively. In Kumi industrial complex, positive responses on traffic and raw material supply and negative reactions on the environmental impact on social community as well as high labor charge were investigated. Especially the higher labor cost prevented to hire laborers effectively. In the linkages of spatial and raw material, most factories in the complex depended on the availability of out side the Kumi city. For the textile factories, the supply of raw material and parts were relied on Taegu and/or other cities, whereas in electronic factories purchased them mainly from other cities and partly from abroad. Although questionnaire and interview suggested it, most of the parts were supplied by a parts maturing companies on the complex to a few large enterprises. In the marketing linkage, textile factories revealed higher relation-ship with the foreign countries and sewing factories in Korea. On the other hand, electronic factories have strong relation-ships in the marketing linkage to the parts supplying companies in the complex or large-scale resembling companies in other cities. In the textile companies, the right for decision on purchasing raw materials and parts is belonging to the owner whereas mother enterprise usually have the right for the marketing. In the case of the electronic factories, all the purchasing activities are related to the sub-contracting companies. In the service linkage, the Quality of the service created spatial distinction. There was high linkages on inside of Kumi complex for the low grade services such as repairing and installing machines, whereas strong linkages on outside of the complex for the high grade services such as management, law, taxation, new product development. and manufacturing technology. In the linkages of activity on the R&D (research and development), electronic factories do not have sufficiently qualified institutes in the complex. Strong regional linkages in the field of textile and electronic industries revealed limitations of the local industrial complex. In the sub-contracting linkage, high linkage ship within Kumi boundary reflected the characteristics of industrial site in the complex. There, most decisions by the companies centered by the mother enterprise.

• Korean Journal of Remote Sensing
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• v.31 no.6
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• pp.531-548
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• 2015

Atmospheric Motion Vector (AMV) from satellite images have shown Slow Speed Bias (SSB) in comparison with rawinsonde. The causes of SSB are originated from tracking, selection, and height assignment error, which is known to be the leading error. However, recent works have shown that height assignment error cannot be fully explained the cause of SSB. This paper attempts a new approach to examine the possibility of SSB reduction of COMS AMV by using a new target tracking algorithm. Tracking error can be caused by averaging of various wind patterns within a target and changing of cloud shape in searching process over time. To overcome this problem, Gaussian Mixture Model (GMM) has been adopted to extract the coldest cluster as target since the shape of such target is less subject to transformation. Then, an image filtering scheme is applied to weigh more on the selected coldest pixels than the other, which makes it easy to track the target. When AMV derived from our algorithm with sum of squared distance method and current COMS are compared with rawindsonde, our products show noticeable improvement over COMS products in mean wind speed by an increase of $2.7ms^{-1}$ and SSB reduction by 29%. However, the statistics regarding the bias show negative impact for mid/low level with our algorithm, and the number of vectors are reduced by 40% relative to COMS. Therefore, further study is required to improve accuracy for mid/low level winds and increase the number of AMV vectors.

• Journal of Trauma and Injury
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• v.21 no.1
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• pp.28-35
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• 2008

Purpose: This study was conducted to examine the clinical significance IV-contrasted helical abdomen computed tomography (CT) as a diagnostic screening tool to evaluate hollow viscus injury in blunt abdominal trauma patients. Methods: This is a retrospective study encompassing 108 patients, presenting to Korea University Medical Center (KUMC) Emergency Department (ED) from January 2007 to December 2007, with an initial CT finding suggestive of intra-abdominal injury. An initial non-enhanced abdomen CT was taken, followed by an enhanced CT with intravenous contrast. Patients' demographic data, as well as the mechanisms of injury, were inquired upon and obtained, initial diagnosis, as dictated by specialized radiologists, were added to post-operational (post-OP) findings and to additional CT findings acquired during their hospital stays, and all were combined to arrive at final diagnosis. Initial CT findings were further compared with the final diagnosis, yielding values for sensitivity, specificity, and accuracy, as well as positive and negative predictive values. Patients were further divided into two groups, namely, those that underwent operational intervention and those that did not. The initial CT findings of each group were subsequently compared and analyzed. Results: Initial CT scans revealed abnormal findings in a total of 212 cases - solid organ injuries being the most common finding, as was observed in 97 cases. Free fluid accumulation was evident in another 69 cases. Based on the CT findings, 77 cases (71.3%) were initially diagnosed as having a solid organ injury, 20 cases (18.5%) as having a combined (solid organ + hollow viscus) injury, and 11 cases (10.2%), as having an isolated hollow viscus injury. The final diagnosis however, were somewhat different, with only 67 cases (62.0%) attributed to solid organ injury, 31 cases (28.7%) to combined injury (solid + hollow), and 10 cases (9.3%) to hollow viscus injury. The sensitivity (CI 95%) of the initial helical CT in diagnosing hollow viscus injury was 75.6%, and its specificity was 100%. The accuracy in diagnosing hollow viscus injury was also meaningfully lower compared to that in diagnosis of solid organ injury. Among patients initially diagnosed with solid organ injuries, 10 patients (2 from follow-up CT and 8 from post-OP finding) turned out to have combined injuries. A total of 38 patients underwent an operation, and the proportion of initial CT findings suggesting free air, mesenteric hematoma or bowel wall thickening turned out to be significantly higher in the operation group. Conclusion: Abdominal CT was a meaningful screening test for hollow viscus injury, but the sensitivity of abdominal CT was significantly lower in detecting hollow viscus injury as compared to solid organ injury. This calls for special consideration and careful observation by the ED physicians when dealing with cases of blunt abdominal trauma.