• Journal of Technologic Dentistry
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• v.37 no.3
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• pp.121-127
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• 2015

Purpose: This study was intended to investigate the effect of applying liner for chemical bonding and physical surface roughness created on zirconia by using a sandpaper before sintering on the bond strength between the two materials. Methods: Zirconia blocks were cut using a low-speed cutter. Plate-shaped specimen($6mm{\times}6mm{\times}3mm$) was fabricated by sintering after giving surface roughness according to four kinds of sandpapers. Depending on whether or not to use liner, 60 specimens were divided into two groups ZN(non-liner), ZL(liner), and the two groups were subdivided into four groups respectively in accordance with sandpaper used, totaling eight groups (n=10). The surface roughness (Ra) values and shapes before sintering were observed, and shear bond strength after pressing ceramic plasticity was measured with a universal testing machine. For a test of the significance, a one-way ANOVA was performed, and Tukey's multiple comparison test was conducted. Results: The observation of the surface roughness was SB04($2.22{\pm}1.16{\mu}m$), SB08($2.98{\pm}0.33{\mu}m$), SB12($2.44{\pm}1.32{\mu}m$), SB20($2.34{\pm}0.59{\mu}m$) and SA04($2.34{\pm}0.67{\mu}m$), SA08($1.28{\pm}0.90{\mu}m$), SA12($2.03{\pm}1.60{\mu}m$), SA20($2.19{\pm}1.73{\mu}m$). In the case of ZN Group, the shear bond strength was ZN04($23.26{\pm}3.83MPa$), ZN08($21.76{\pm}2.33MPa$), ZN12($20.49{\pm}3.01MPa$), ZN20($24.98{\pm}4.22MPa$)(p<0.05). As for ZL Group, the shear bond strength was ZL04($25.09{\pm}5.67MPa$), ZL08($22.98{\pm}2.26MPa$), ZL12($21.54{\pm}5.70MPa$), ZL20($23.98{\pm}3.23MPa$)(p<0.05). Conclusion: The research results showed that the bond strength of Zirconia core and Pressing ceramic was further improved by physical surface treatment before sintering, rather than by chemical bonding through liner surface treatment.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.445-453
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• 2014

The purpose of this study was to examine the necessity of oral health education to analyze the knowledge and status of oral health according to smoking in some college students. The subjects in this study were 217 selected college students, on whom a survey was conducted from September 3 to September 7, 2013. The data were analyzed using SPSS 19.0(SPSS 19.0 K for window, SPSS Inc USA). The findings of the study were as follows: First, concerning toothbrushing frequency, the smokers brushed their teeth twice, and the nonsmokers did that three times(p<0.05). The male students did toothbrushing twice, and the female students did that three times(p<0.05). As to scaling experience, the female students got their teeth cleaned more often(p<0.05). Second, the nonsmokers who had received oral health education outnumbered the smokers who had(p<0.01). In regard to the necessity of smoking-related oral health education, both of the smokers and the nonsmokers replied it was necessary(p<0.05). Third, as for the level of oral health knowledge, the nonsmokers were more aware than the smokers that the use of oral hygiene supplies had an effect on the prevention of dental caries(p<0.05). Given the findings of the study, the smoking-related oral health education and the development of programs that are intended for college students seems necessary.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.113-124
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• 2012

The purpose of this study is to analyze community members' perception due to impacts on use and development of Dulegil in Bukhansan National Park. The study was conducted by questionnaire survey sent to community members of the vicinity of Dulegil. Average score of positive impact on the local community was 3.2. Positive impacts mentioned by community members were 'heightened pride in their community with increased community image' and 'improvement of landscape and natural environment.' Improved residents' awareness of landscape and natural environment indicated that Dulegil almost accomplished intended goal of preservation of ecosystem. However, actual effects on ecosystem preservation and local economy were not perceptible yet. Score of negative impact was 2.8 on average. 'Traffic congestion' and 'increase in noise level' were considered the most serious among the negative impacts. Environmental pollution and destruction of vegetation in the lowland were deemed relatively bad. Regarding resident awareness of community, those in their 50s and older were quite satisfied with the community. However, young people showed lower level of satisfaction. In order to satisfy all ages, infrastructure and programs for the youth should be in place. To minimize negative awareness of impacts of Dulegil, visitor's attitude should be changed, and education and training on the value and mind set of horizontal hiking are required.

• The Korean Journal of Archival Studies
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• no.25
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• pp.233-278
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• 2010

An interest in various description of history was increased, resolutely breaking away from the existing frame also in a historical science world, under the influence of post-modernism arisen from the mid 20th century, and for this, oral history archives and oral history methodology began to attract the attention in various academia including archival science as a method for a new writing of history. Also, under the circumstance of korea having a difficulty in performing a whole reconstruction of modern age history and a liquidation of past affairs due to an absolute lack of archives, the tendency is toward more active management of oral history archives and establishing oral history archives in the context of an excavation of new archives and a reinterpretation of history, owing to the necessity in a particular situation. This article started with a critical mind regarding an absence of a collecting policy which can help an effective development of collection from a point of view of archival science, with regard to oral history archives that recently shows a rapid increase of an interest. For this, this article intended to present an new element of a collecting policy besides the study on a collecting policy performed meanwhile by an archival science world by noticing a characteristic and a collecting method of oral history archives, this can be examined largely through 'a statement of mission and collection purpose', 'a policy of collection at large', 'a definition of maintenance and use of the holdings', and 'a guide for a development of collection', and add a proposal regarding a plan to embody the parr which should be actually applied to collection of oral history archives among the existing constituents.

• Journal of the Korean Society of Floral Art and Design
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• no.43
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• pp.19-37
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• 2020

The purpose of this paper is to seek for a new exhibition form of floral art design that deviates from formalism by suggesting a planning exhibition with storytelling away from the unilinear exhibition composition method of floral art design currently being held in Korea. Storytelling in flower art exhibition is to construct an easy-to-understand exhibition through the use of the four-step construction method of introduction-development-turn-conclusion, or the three-step construction method of intro-body-conclusion. It is intended to efficiently propose interaction between creators and viewers. In order to seek for diversification of floral art design, it is necessary to secure a convergent view that has been blowing since the Millennial, collaborate with other fields, or attempt exhibition planning that reflects storytelling. The main function of the exhibition is to meet and communicate directly with the public. This study intends to propose the exhibition structure and implementation direction of floral art exhibition through the case of 'Hwawanggye' held at the Sungkyunkwan University Museum in 2017, focusing on the exhibition where storytelling is applied. Through this study, it is expected that the discourse in the field of floral art will be expanded, and various networks of aesthetic suggestions and floral art design with storytelling will be boosted.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.570-582
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• 2022

Nucleoplasty is a type of percutaneous disc decompression that has been developed to treat herniated intervertebral discs. Currently, in some clinics, researchers have also applied this procedure to patients with internal disc disruption, apart from the originally intended usage on herniated intervertebral discs. The purpose of this study is to evaluate the feasibility of this extended use based on medical logic. To achieve this, the author analyzed case studies on performing nucleoplasty on patients with internal disc disruption. The main points of the analysis are, first, the validity of the treatment evidence presented by the researchers and, second, the relevance of the patient selection criteria. As a result, it is judged that the therapeutic rationale of existing papers applying nucleoplasty to the treatment of internal disc disruption is unclear or inconsistent with general medical logic, and in the process of patient screening, discs that may be deemed inappropriate for percutaneous decompression are included. Therefore, the author believes that existing studies applying nucleoplasty to the treatment of internal disc disruption have the nature of somewhat adventurous experiments that are unnecessary or can cause potential side effects. In order to uphold patients' rights and improve the completeness of the study in the research process on this topic, the author thinks that it is essential to establish clearer therapeutic evidence than the current level of understanding and to have an elaborate patient screening process based on it.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6D
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• pp.737-743
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• 2009

Shield TBM, since it was employed for Suyoungman Bay riverbed tunnel of Busan Subway in 2000,has been increasingly adopted in Korea, and in line with growing popularity, the study on Shield TBM has been expanded. However the studies mostly focus on ground condition in a bid to estimate the advancement rate and develop the model for calculating the excavation efficiency, whereas the efforts to analyze the cause of delay and to develop the improvement measures have been neglected. Thus the studies were mostly intended to analyze the schedule slippage focusing on ground conditions, while the study on schedule behind due to equipment itself and related facilities have yet to be attempted in earnest. This study hence was aimed at evaluating the troubles and schedule slippage caused by mechanical elements such as shield TBM equipment and tools and ground conditions, making use of FMEA approach so as to analyze the risk of schedule delay by such elements, thereby proposing the preventive measures to deal with high-risk factors. So, this study suggest the solution to highly ranked trouble factor for the purpose of enhance the efficiency on Shield TBM.

• The Korean Journal of Nuclear Medicine Technology
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• v.25 no.2
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• pp.29-34
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• 2021

Purpose Sample reception environment system in nuclear medicine has not changed much compared to 20 years ago. When preparing sample for in vitro test, there was no significant change because the test was carried out by generating an own specimen from the parent specimen. In this study, We would like to introduce a method that automatically removes the sample cap using the automated decapper equipment and enables automatic reception at the same time. In addition, including a provisional reception system. Materials and Methods In 2019, it was intended to get a device that automatically removes the cap of a patient's blood sample. This equipment is the same as the equipment used in the Department of Laboratory Medicine (Vacuette Ⓡ Unicap Belt Decapper, Greiner bio-one, Austria). However, the purchase was delayed due to differences in tube size, budget, and space. In January 2020, we borrowed domestic automatic decapper equipment and modified it to suit our laboratory environment. After 9 months, we were able to introduce a system that automatically removes the lid of a patient's blood sample and at the same time automatically accepts the test. And, through the provisional reception system, it was possible to know the arrival of the specimen in a short time. Results With the use of an automatic decapper device, the sample cap was automatically removed, and the reception proceeded at the same time. So, it was very efficient at work because it shortened the sample preparation time by about 20 minutes. In addition, it was possible to prevent the examiner's musculoskeletal disorders caused by repeated wrist use. After using the provisional reception system, patients were able to be discharged quickly, and the number of phone calls to confirm the arrival of samples was reduced. Conclusion Most hospitals have about four employees in the nuclear medicine in vitro laboratory. It is effective to use automatic decapper equipment and a provisional reception system for organizations that perform work with the minimum number of personnel.

• Journal of Korean Home Economics Education Association
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• v.18 no.4 s.42
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• pp.127-141
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• 2006

The purpose of this study was to investigate the actual conditions of the use of them and the moves to strengthen home economics resources for school lifelong education for parents and local residents. This study conducted a systematic random sampling. Questionnaires were distributed to home economics teachers from 285 middle schools, 123 high schools, and 130 of them were sampled as the subjects of this study. The results of this study were as follows. First, home economics teachers were active participating school lifelong educational program. But according to the result of research on the actual condition, the proportion of taking part in it was low. More than half of home economics teachers who took part in program's lecturer were in charge of computer courses. So they didn't show their ability as expert. Also they were in charge of several works than roll of lecturers. It was mentioned too great a burden. There is little in-service training for meeting specialization for school lifelong education. They wanted to take part of lecturers of program and preferred hours of being over class. More than half of them had intended to obtain a lifelong educator's license. The part of elective courses for obtaining a lifelong educator's license is similar to home economics educational contents. So, they have an advantage of obtaining it. Second, one-fifth of school that gave school life education carried out program of related home economics. Mostly they had mothers of students-oriented programs on artistic and leisure. But this is that home economics teachers mentioned less important teaching at society in the future. They importantly mentioned program on children's education in now and the future. Parents of students and local residents also extremely wanted it. For differentiated school life education, quality of programs is important greatly. Third, the actual condition of practical room relating home economics is only practice to cook mostly. So they are reluctant to be open it because of being responsible for the results from using there. It is necessary to ameliorate there's facilities and to increase there's area. Fourth, home economics teachers want to improve their specialization through in-service training, to develop and diffuse programs of superior quality, and to get extra pay for overtime from the government.

• Journal of dental hygiene science
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• v.6 no.1
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• pp.11-17
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• 2006

The purpose of this study was to help prevent the turnover of competent dental hygienists in a bid to boost the efficiency of personnel management for dental health care workers and provide higher-quality oral health services. After relevant literature and data were reviewed, a survey was conducted on dental hygienists, who worked at dental institutes, for approximately four months from September to December 2004 to identify what affected their turnover. The findings of the study were as below: 1. Regarding turnover experience, 39.7 percent of the dental hygienists investigated had such an experience. As to turnover frequency, those who took up another employment once made up the largest group(28.2%), followed by twice(8.0%) and three times(2.9%). The most dominant turnover reason was working conditions(66.7%), followed by seeking being hired by larger institutes(36.2%), pay(21.7%), relationship with dentists(11.6%) and commuting distance(11.6%). 2. As for their hope for turnover, 82.8 percent hoped to take up another employment, and working conditions were cited as the most common reason(44.4%), followed by pay(33.3%), commuting distance(18.1%), marriage(13.2%), health/use of leisure time(11.8%), and commuting time(10.4%). 3. Concerning preference for future workplace, 38.5 percent, the largest group, wanted to work at public health clinics. As to a preferred term of working as dental hygienists, 50.0 percent, the greatest group, hoped to serve as dental hygienists until they are financially secure. 34.5 percent, the second largest group, intended to keep working until they reach the age limit. In regard to their responsibility for family economy, 47.7 percent, the greatest percentage, shouldered the partial responsibility for that, and 31.6 percent assumed no responsibility. 4. As to their intention to quit working as dental hygienists, 61.5 percent were willing to do that, and marriage(29.0%) was singled out as the most frequent reason, followed by working conditions(27.1%), child birth(22.4%), health/housework(18.7%), pay(15.9%) and learning/use of free time(15.0%).