• The Journal of Korean Academy of Prosthodontics
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• v.35 no.4
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• pp.647-661
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• 1997

The resin modified glass ionomer cements(RMGICs) have been used for years since 1989. Recently it has been developed for luting of fixed restorations. To evaluate the bond strength and marginal leakage of RMGICs for luting usage, the 80 extracted human molars which had uniform area of exposed dentin were cemented with 3 types of RMGICs(Fuji Duet, Advance, Vitremer), a conventional Glass Ionomer Cement(GIC-Fuji I), and a resin cement (Panavia 21) to base metal alloy(Ni-Cr-Be). After thermocycling the specimens were immersed in basic fuschin dye for measuring marginal leakage. The shear bond strength was measured with Instron and the maximum dye penetration was measured to 0.1mm. The types of fractured patterns were determined with stereoscope(${\times}7.5$). The results are as follows. 1. The difference between 3 RMGICs and a conventional GIC in shear bond strength was not statistically significant. It seemed that RMGICs had lower shear bond strength than resin cement. (p<0.01) 2. The mean scores of marginal leakage had no significant difference between the resin cement and 3 RMGICs but it was much higher in conventional GIC than the RMGICs (p<0.05) 3. It was determined that the manufacturer and the methods of dentin pretreatment determined the pattern of fracture surfaces and the frequency of adhesive failure between teeth and 3 RMGICs standed as in following order - Vitremer, Advance, Fuji Duet. (p<0. 01) When the fracture pattern was analyzed, it could be said that the materials and the method of dentin pretreatment have much effect on bonding states. This means that the dentin bonding agents should be improved. But the limited products in this experiment can not evaluate the physical properties of the entire RMGICs. Therefore a further study which can evaluate various RMGICs should be in progress to develope better cements.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.4
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• pp.423-432
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• 2019

Along with an increase in marine activities every year, the frequency of marine accidents is on the rise. Accordingly, various research activities and policies for marine safety are being implemented. Despite these efforts, the number of accidents are increasing every year, bringing their effectiveness into question. Preliminary studies relying on annual statistical reports provide precautionary measures for items that stand out significantly, through the comparison of statistical provision items. Since the 2000s, large-scale marine accidents have repeatedly occurred, and case studies have examined the "accident response." Likewise, annual statistics or accident cases are used as core data in policy formulation for domestic maritime safety. However, they are just a summary of post-accident results. In this study, limitations of current marine research and policy are evaluated through a literature review of case studies and analyses of marine accidents. In addition, the ontology of the marine accident information classification system will be revised to improve the current limited usage of the information through an attribute analysis of boating accident status reports and text mining. These aspects consist of the reporter, the report method, the rescue organization, corrective measures, vulnerability of response, payloads, cause of oil spill, damage pattern, and the result of an accident response. These can be used consistently in the future as classified standard terms to collect and utilize information more efficiently. Moreover, the research proposes a data collection and quality assurance method for the practical use of ontology. A clear understanding of the problems presently faced in marine safety will allow "suf icient quality information" to be leveraged for the purpose of conducting various researches and realizing effective policies.

• Korea Science and Art Forum
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• v.29
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• pp.279-292
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• 2017

This study was started by recognizing that visual storytelling(VST) is an important factor that determines the success of the work. The goal of this study is to analyze the VST study approaching from the narrative and visual dimension by analyzing the conflict intensity and VST factor. Therefore, in this paper, we analyzed the conflicts of the theater animation(4) that succeeded in the worldwide success and attempted the VST interpretation by approaching it technically. The results and contents of the study are as follows. Firstly, based on the narrative theory of Sung bong-Sun and Robert McKee, we classified the conflict scenes and found the kinds of conflicts. In addition, based on the 5B model, a total of 108 conflict shots were extracted. Secondly, through expert experiment, we found the conflict intensity of conflict shots. Thirdly, the visual elements of fifteen significant conflicts were extracted from internal and super individual conflicts. Fourth, as a result of the experiment, it was confirmed that the reliability of the visual elements in the inner and super personal conflicts was in the range of 100-83.33%, and the frequency of usage was found to be widely distributed in 5.88-70.59% and 5-70%. This means that the VST expression, which relied on the sense of the artist, can be engineered. Finally, I expect that it will be the basis of the development of the VST Tool which can predict the conflict expression of the work in the animation pre - production stage successfully.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.161-166
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• 2016

By studying the status of oral health provided by caregivers working in care facilities in accordance with their oral health awareness and knowledge, this thesis sought to find a plan of development to enhance the oral health for the elderly in care facilities. A survey was carried out from the 16th of August to the 2nd of September 2016, with 200 care givers as the subjects, working in 14 long-term care facilities for elderly, located in the city of D. Frequency analysis and independent sample t-test were conducted of the collected data, using SPSS 18.0. The results of the study were as follows; for gender, female was 91.5% which was higher than that of male, and married for marital status, 50 for age, highschool for education, christian for religion were shown to be the highest. The highest number of people for daily care was 6~7. In terms of status for providing oral health and oral health awareness of caregivers, the existence of oral hygiene guideline was statistically meaningful, and in terms of the status of oral health provided and oral health knowledge, there were notable differences in storage of dentures, and usage of mouthwash(p<.05).

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.7-11
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• 2008

In order to investigate the application of bamboo in various ways in floral designs, we analyzed 108 bamboo items from the monthly magazine 'Fleur' and from the International Flower Contest held from 2001 to 2006. We analyzed the frequency of usage of bamboos by the used parts, kind of design, type of design, and arrangement method in the design work. In terms of the used parts of the bamboo, stems took 90% of the whole work. Among the 77 designs that used stems, excluding the 20 work items presented in the International Flower Contest which has been held in April, number of the bamboo work items peaked at the beginning of the year in January and February, and during summer (July and August). Upon analyzing the type of stems that were used in the 97 works, 63% of the works used bamboo in natural state, but not processed. 48% of the works used the vertical-parallel method among the arrangement methods. Other categorized works were rounded works that were not included in the vertical, horizontal or diagonal mathod. More than 50% of the works, including the table decoration, used space decoration. Among the types of work design that used bamboo as material, 64% were decorative type, 30% graphic type, and 4% formal-linear type.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.2
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• pp.1-12
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• 2019

The purpose of this study is to compare and analyze how many species of trees presented with scientific names are on the written test for engineer landscape architecture, as their usage has increased in the landscape industry in recent years. The following is the result of comparing and analyzing the species of trees which are frequently used in landscape, planting construction, and the scientific name questions presented in the previous 6 years by year on the written test for engineer landscape architecture. First, the results of analyzing the examination question frequency by year in the landscape planting subject showed a gradually declining trend from 2014 after peaking at 56.6% in 2013. Second, 163 species of trees using scientific names were presented in questions on the written test for engineer landscape architecture over the previous 6 years and these included Betula platyphylla, Sophora japonica, Cercis chinensis, Taxus cuspidata. The number of species of trees used in landscape construction during the same period was 169 including Pinus densiflora, Chionanthus retusus, Cornus officinalis, Syringa dilatata. The result of interviews with landscape planting construction officials showed that when choosing the species of trees, they emphasize ecological characteristics, such as the ratio of trees to shrubs, flowers and autumn leaf characteristics, and also consider the morphological characteristics, landscape characteristics, economic feasibility, and the supply and demand situation. Third, it was found that 70 (42.9%) out of 163 species of trees presented with scientific names on the examination were not used in landscape planting construction and 76 (44.9%) out of 169 species were not used as material for questions. As for the scientific name questions, deciduous trees and evergreen shrubs accounted for the more questions, Evergreen and deciduous tree and shrubs were most common in landscape planting construction as well.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.156-170
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• 2023

Objectives: This study conducted practical training to improve the proper usage of personal protective equipment(PPE), which greatly impacts workplace safety and health management. Personal protective equipment education was conducted through active participation, without theoretical modules, and aimed to identify the effects of repeated practical education and determine ways to increase participant satisfaction. Methods: Study data were analyzed using the IBM SPSS Statistics ver.29 software. First, participants' general characteristics were analyzed with frequency analysis. Second, the normality and equality of variances (Leven's test) were tested for the dependent variables prior to statistical analyses to determine the use of parametric tests. In general, normality is assumed when the sample size is 30 or more per the central limit theorem (Park et al., 2014). As our sample size of health management workers was 43, normality can be assumed. However, to ensure rigor of the study, we examined skewness and kurtosis. The results confirmed that the data were normally distributed. Third, the effects of repeated PPE training were analyzed using paired t-tests. Fourth, differences in satisfaction with PPE training according to the safety and health job position and safety and health certification were analyzed with t-test and Welch's t-test. For parameters that did not meet the assumption of equal variances, the Welch's t-test was performed. Results: Repeated PPE training improved the educational outcomes, and the improvements were significant in the 1st and 2nd respiratory PPE and safety and hygiene PPE training evaluations (p<.001). In terms of safety and health job position, repeated training led to improvements in educational outcomes, with significant improvements observed among supervisors and specialized health management institution workers in the 1st and 2nd training evaluations (p<.005). In terms of safety certification, repeated training led to improvements in educational outcomes, with significant improvements observed among both certified and non-certified individuals (p<.005). Regarding satisfaction with PPE training according to safety and health job positions, specialized health management institution workers showed greater satisfaction than supervisors, with significant differences in the satisfaction for expertise of lecture, work relevance, and lecturer's attitude (p<.001). Regarding satisfaction with PPE training according to safety and health certification, satisfaction was higher among certified individuals, with significant differences in satisfaction for work relevance and lecture attitude (p<.05) Conclusions: PPE education should be recommended to be provided as practical training. Repeated training can enhance educational outcomes for individuals with inadequate knowledge and understanding of PPE prior to education. For individuals with high levels of pre-existing knowledge and understanding of PPE, the results show that various training experiences should be provided to enhance their satisfaction. Therefore, it suggests that the workplace should actively seek educational media and methods to acquire expertise and skills in wearing personal protective equipment and improve the ability to use

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.762-768
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• 2015

This study examined the integration value of a low level pilotis space, a component that has been often selected as an essential planning element of the recent high-rise apartment complex, and compared the main outdoor unit spaces with that of an average integration value of the individual complexes. Furthermore, this study provided the preliminary data for the next level of research, which is the observation of the pilotis space usage behaviors and the frequency of utilization. The results of this present research are as follows. First, from the main outdoor unit spaces of the high-rise apartment complexes including the pilotis space, a 'complex entrance' or a 'plaza' space showed the highest integration value. Second, the spatial integration value of a pilotis space in a high-rise apartment complex was generally lower that of the integration value of other main outdoor units. Third, from the pilotis spaces of the high-rise apartment complex, those with a 'projecting entry access + pilotis addition type' that did not provide an access to the individual units, had the lowest space utilization rate by the inhabitants; thus, had a high likelihood of the spaces becoming used for illegitimate activities or becoming vacant.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.9-20
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• 2017

Camp Page, which has been located in front of Chuncheon Station for about 50 years since 1958, recently opened to the public. Chuncheon City is currently struggling to construct a park on this site due to an uncertainty of general plans and financial difficulties. Accordingly, this research conducted a cognitive survey about site usage with Camp Page users in order to clarify directions for efficient establishment of parks within the former military base. The course of research includes analytical methods such as a survey targeting Chuncheon citizens and tourists both in the field and online, a frequency analysis of 1,360 index samples, a cross analysis and t-test. As a result, firstly, Chuncheon citizens recognized the image of Chuncheon as a city with a fresh, clean lakeshore whereas tourists think of it as a city for sightseeing and leisure. Hence, it was justifiable to conclude that the city should organize various programs for people to enjoy leisure activities while at the same time protecting the environment. Second, the awareness of tourists about Camp Page was relatively low and both citizens and tourists recognize that it was not sufficient enough for enjoyment of free time. The majority answered "space for culture and art and for experiencing the natural environment" when asked about the direction of space creation at Camp Page, which indicates that the site will need to be available both for cultural art and nature experiences. Lastly, it was thought that the direction of developing leisure facilities in Chuncheon city should include the improvement of worn out installations and developing chain products among programs. This research will be able to use fundamental data for the efficient utilization of the returned U.S. military camps that are constantly merging.

• Journal of The Korean Association of Information Education
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• v.17 no.1
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• pp.1-8
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• 2013

SNS is a social networking service that removes the barrier between cyber spaces and the real world and helps people who have common interests to have a two-way communication, manage their interpersonal relationships and share information. The domestic and international SNS markets have attained a steady growth, and their growth is being more accelerated in recent days. However, studies on SNS have just examined adults, and it's required to research the use of SNS and cyber behaviors via SNS among elementary and middle school students. This study attempted to analyze the relationship of the use of SNS, motivation of using SNS, the use of active SNS functions, SNS-dependent tendency and SNS awareness to cyber behaviors via SNS among elementary and middle school students. As a result, regardless of gender and grade, stealing private information was the most frequent activity and the frequency of 'contacting strangers' activity increased most rapidly with the usage time and grade. SNS dependency turned out to be the most highly correlated with the negative cyber behavior. Moreover, the difference of gender was not significant to the overall negative cyber behavior, whereas that of grade was.