• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.317-318
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• 2003

전기활성고분자인 poly(vinylidene fluoride)(이하 PVDF로 약기)와 전기비활성 고분자와의 혼화성블렌드에서 외부전장이 이 블렌드의 상분리거동에 미치는 영향을 조사하기에 적합한 전기비활성고분자를 찾은 결과 측쇄에 C=O기를 갖는 poly(ethyl methacrylate)(이하 PEMA)와 주쇄에 C=O기를 갖는 poly(1,4-butylene adipate)(이하 PBA로 약기)가 좋은 후보 고분자로 사용가능함을 보였다. 측쇄에 C=O기를 갖는 고분자인 PMMA와 PVDF와의 블렌드에서 PVDF의 융점보다 상당히 높은 온도인 35$0^{\circ}C$ 이상의 온도에서 lower critical solution temperature (이하 LCST로 약기) 거동을 보이는 것으로 알려져 있기 때문에 [1] 실제로 이들 블렌드계에서 열분해를 배제하면서 LSCT거동을 실험적으로 관찰하기는 불가능하다. (중략)

• Journal of dental hygiene science
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• v.6 no.3
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• pp.227-230
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• 2006

This purpose of this study was to provide the basic data for preventing dental caries, and maintaining and enhancing oral health. The subject of this study through the survey of the recognition of oral health, a questionnaire survey was conducted for 545 male and female students who were in the 4th, 5th, 6th grade of elementary school in Ulsan city. Statistical analysis was conducted using the SPSS 11.5 with t-test, ANOVA and correlation. The obtained results were as follows 1. Oral health knowledge false for Dental floss silk, Fluoride and very low. 2. The students who were in the 4th, 5th, 6th grade of elementary school is Oral health knowledge, behavior and tooth brushing frequency 4th 5th grade higher than 6th grade(p = 0.000, p,0.005). 3. Oral health knowledge is higher behavior high date (p = 0.001), and Oral health behavior is higher many tooth brushing frequency (p = 0.000).

• Journal of Korean society of Dental Hygiene
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• v.11 no.6
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• pp.973-983
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• 2011

Objectives : The oral care during early childhood plays an important role to maintain sound oral health during adulthood. As the number of children's using child care facilities is on the rise recently, the children's oral health awareness and behavior of the educators at nurseries and kindergartens are to be examined. Methods : A self-recording survey was conducted on 194 educators at the nurseries and kindergartens in Chungnam region. Results : The most frequently given snack was milk, 91.8 percent of the facilities had children brush their teeth, 63.4 percent made them apply fluoride and 56.2 percent kept children's toothbrushes in an ultraviolet rays sterilizer. There was a meaningful difference in the awareness of the necessity to educate children about oral health according to the offer of the opportunity to apply fluoride (p<0.05). A meaningful difference was found in the recognition of the necessity to educate children according to their grade (p<0.05) and to train teachers themselves (p<0.05). The most desirable persons in charge of oral health education were dentists in health centers (46.9%) in order. The more experience in teaching they have had (p<0.05), when they're married (50.5%) (p<0.05) and when they're not homeroom teachers (52.6 percent), the more regular checkups they have had (p<0.05). As for the importance of oral health and the results of regular checkups, those who had answered 'very important'(42.4%) showed higher rate of regular checkup (p<0.05) than those who had answered 'important'(23.9%). When teachers have the experience to get trained about oral care (96.3%), the practice frequency of brushing teeth was proved to become higher (p<0.05). Conclusions : The educators for children should recognize the importance of oral health education, educate children to practice oral health care, and the environment and systematic foundation should be established which the educators manage effectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.1
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• pp.11-19
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• 2015

The production of nuclear fuel cladding tube is expected to increase with the nuclear power plant expansion. Zirconium(Zr) scrap that is generated during manufacturing is also expected to increase. Zr electrorefining experiment was carried out in the fluoride salt of LiF-KF-ZrF₄ using multiple electrode for scale up and improving throughput Zr electrorefiner develop-ment. The Zr reduction peak observed at-0.8 V(vs.Ni). Polarization behavior showed that the amount of applied current increases because of decreasing cell resistance as the number of cathode increases. Experimental results showed the highest recovery rate about 98% at lowest current density of 25.64 mA/cm² using 6 electrodes. XRD and TG analysis result show that pure Zr was recovered 99.92% and ICP analysis shows that lower impurity content than conventional impurity content of the Anode(97.8%). Electrorefining consumes energy about 7.15 kWh/kg less than 39.7% compared to the Kroll process using 6 electrode width of 20 mm and height of 65 mm. Because of increasing cell efficiency and recovery rate, using multiple cathode is determined as an efficient technique for scale up electrorefining Zr scrap.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.256-264
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• 2018

The purpose of this study was to investigate the relationship between oral health behaviors and the results of the oral dysentery test for dental hygienists and students at Gyeonggi - do and Chungcheongnam - do. Self - filling questionnaires and oral diseases. The following conclusions were obtained. The most common toothbrushing frequency was three times a day (60.2%), and the most dominant frequency of eating between meals was once or less(49.7%). The most common snack that they had was stickiness-free sweetened food(66.5%), and the type of beverage that they had the most was sweetened beverages(49.7%). The average stimulated saliva flow rate was 9.41ml, and they got a mean of 9.52 in the buffering capacity of saliva. The average glucose clearance time was a mean of 12.02. When they took a streptococcus mutans colony count test, 80.1 percent belonged to the low-risk group(<$10^5$), and 82.6 percent belonged to the low-risk group(<$10^5$) when a lactobacillus test was conducted. There was a positive correlation between the irritant saliva fraction and the non-irritating saliva and saliva buffering ability. In the fluoride application experience, the glucose retention time was 10.66 minutes and the fluoride application experience was 13.33 minutes. (P = .008). The importance of oral health, which is directly linked to general health, should be emphasized in order to improve the quality of life as well as the life expectancy. For oral health, which is directly linked to systemic health, it is necessary to provide opportunities for oral health education that can be easily accessed by the public, and to continuously develop and provide oral health care programs for a lifetime.

• Journal of Korean society of Dental Hygiene
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• v.12 no.4
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• pp.707-714
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• 2012

Objective : This study came to be carried out in order to develop oral health education program for maintaining adolescents' oral health and to be helpful for qualitative improvement in prevention program by surveying the awareness and behavior on preventive method of dental caries in adolescents. Method : The collected materials of totally 1,100 people who responded were carried out frequency analysis by using SPSS 12.0(Statistical Package for the Social Science). Results : 1. As for the results of awareness on fluoride effect and sealant effect, the students with response to 'effect of preventing decayed tooth' were indicated to be the highest. It was indicated to be the highest in girls as for gender and in the 2nd grade as for school year. (p<0.05). 2. As for the results of being created when eating sweet food and carbonated drink, the students with response as saying that 'a decayed tooth occurs well' were indicated to be the highest. 4. As for the results on the aim of visiting dental clinic, the students with response as saying of 'visiting for having treatment' when tooth is painful were indicated to be the highest. Conclusion : Synthesizing this study, the students' awareness on preventive method of dental caries was high. But the practice on regular check-up or diet was indicated to be low. Through oral health education, the adolescents should be not only delivered information or knowledge, but also changed habit and behavior.

• Journal of dental hygiene science
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• v.22 no.1
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• pp.44-50
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• 2022

Background: This study compares and analyzes the degree of oral health information literacy by 25% for upper and lower grades to assess how differences in mothers' oral health information literacy affect infants' oral health behavior. Methods: The study surveyed 201 mothers with infants and children using a 36 question survey tool. Cross-analysis was conducted to determine the difference in oral health information literacy between the upper and the lower 25%. Results: Comparing 25% of the upper and lower grades of verbal oral health information literacy scores, the word with the most significant difference in the correct answer was resin. An item asking about the time to eat after fluoride varnish application showed the most significant difference in the correct answer on the functional oral health information literacy scale. Mothers' oral and functional oral health information literacy scores showed that verbal literacy was statistically significant for brushing guidance after children's meals, brushing guidance before children's bedtime, food intake restrictions before bedtime, and restrictions on consumption of cavity-inducing foods (p<0.05). Functional literacy was statistically significant in the post-brushing test of children and the correct brushing method map items (p<0.05). Conclusion: As a result of comparing and analyzing the upper and lower 25% of the mother's oral health information literacy, it was found that the mother's oral health information literacy affected the infant's oral health behavior. Therefore, systematic education is needed to raise literacy by grasping the level of oral health information literacy of mothers, and oral health education by level according to oral health information literacy should be developed.

• The Journal of the Korea Contents Association
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• v.17 no.7
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• pp.498-504
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• 2017

Oral health behavior such as toothbrushing one's teeth, using dentifrice and such are an important part of improving one's oral health and therefore quality of life. However, it is also necessary to research exposure to harmful chemical substances. Therefore, this study investigated the factors that affect researching fluorine exposure resulting from oral health behavior initiation so that correct oral health guidelines can be provided. As a result of applying the fluorine compound's oral exposure in the ConsExpo 5.0 model, adult males' oral external dose was at 0.000196 mg/kg, oral acute (internal) dose at 0.000196 mg/kg/day and oral chronic (internal) dose at 0.000465 mg/kg/day. In the case of females, the oral dose was at $4.1{\times}10^{-6}mg/kg$, oral acute (internal) dose at $4.1{\times}10^{-6}mg/kg$ and oral chronic (internal) dose at $9.99{\times}10^{-6}mg/kg/day$.

• Journal of the Korea Convergence Society
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• v.7 no.1
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• pp.97-104
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• 2016

This study was to examine relation of oral health knowledge and oral health behavior, targeting university students who major in health-related majors 198 students and health-unrelated majors 203 students. Oral health behavior by general characteristics appears most highest junior and senior sophomore, health-related major, regular dental check-up, dental education experience. 'It is effective in preventing bad breath brushing the tongue when brushing' of oral health knowledge reached 94.5% most highest. The health-related is high 'fluoride helps to prevent cavities.' 'Brushing tongue' of oral health behavior is most highest average 4.20. The health-related is high 'I know the brushing method that's right for me, and enforcement' and 'I am regular scaling for periodontal disease prevention'. To identify influence that general characteristics and oral health knowledge to oral health behavior, regression analysis result Y(oral health behavior)=2.692+0.377(regular dental check-up)+0.145(rental education experience)+ 0.215(method of oral health education)+0.045(oral health knowledge) was come out. Therefore, university students need to improve their oral health, structuring environment where information about oral health is reached out easily.

• Journal of the Korean institute of surface engineering
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• v.27 no.4
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• pp.207-214
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• 1994

In consideration of global environmental protection and fuel saving, aluminum alloy sheets for auto body panels such as hood, fender etc., are expected one of the most promising materials for weight saving of cars. The chemical conversion coating is required to prevent the filiform corrosion occurring on painted aluminum. However the conventional process for the composited material mixed with aluminum and steel is complexs; aluminum part is chromated and assembled to the body, and then the steel body undergoes Zn phosphating. In order to overcome the low productivity due to the complex process and the environmental problem with a conventional process, a simultaneous zinc phosphating process for alsuminum and steel in an assembled condition is demanded. Newly developed phosphate solution has been investigated to characterize the phosphating behavior under various conditions. The optimum conditions of the phosphating solution for the application of the paint treatment derived as follows : about 0.3 for the ratio of Zn to $PO_4$, , 200~500 ppm for the concentration of fluoride ion, and 2.5~4.0 for pH. The concentration of dissolved aluminum ion must be kept below 2--ppm and suitable accelerator is found to be a mixture of 1g/$\ell$ $NO_2\;^-$, and 6g/$\ell$ $NO_3\;^-$.