• The Journal of Korean Academy of Prosthodontics
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• v.59 no.3
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• pp.291-298
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• 2021

Purpose. The purpose of this study is to compare five interdental cleansing products' effectiveness on removing artificial dental plaque on the interdental space of zirconia crowns. Materials and methods. A model with abutments on the right mandibular second premolar and first molar were prepared. 10 zirconia crowns for each abutment were fabricated. After applying artificial dental plaque between the zirconia crowns, a single clinician attempted to remove the plaque with five products: interdental toothbrush, end-tuft toothbrush, dental floss, Easypick, Water pik. They were conducted 10 times per group. The aspect and area of removed surfaces were analyzed using images taken with a digital camera. One factor analysis of variance was performed as a statistical analysis, and a post-hoc test was performed using the Scheffé method (P < .05). Results. There were differences in the area and the pattern according to the characteristics of the products. The largest area, including the marginal portion, was removed in the dental floss group. Interdental toothbrush group was the most effective in removing the dental plaque at the marginal portion. Easypick was less effective than the interdental toothbrush. The end-tuft toothbrush showed better results than other products in cleansing mesiobuccal and distobuccal area, but could not cleanse the area directly below the contact point. In Water pik group, artificial dental plaque was scarcely removed. The removal rate of artificial dental plaque was in the order of floss (69.47%), end-tuft toothbrush (49.36%), interdental toothbrush (44.20%), Easy pick (13.04%), and Water pik (0.59%). Conclusion. Dental floss showed the highest removal rate in the interdental space restored with zirconia crowns, while interdental toothbrush was the most effective in removing the dental plaque at the marginal portion.

• Korean Journal of Heritage: History & Science
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• v.55 no.2
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• pp.102-111
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• 2022

Termites are a group of social insects that are one of the primary causes of damage to wooden architectural heritage. Since termite damage impairs the authenticity and structural stability of cultural heritage, it is imperative to prevent it. This study examines the extent of termite damage to wooden architectural heritage as part of efforts to prevent termite damage to nationally designated wooden architectural heritage sites across the country. The extent of termite damage to each cultural heritage was assessed qualitatively and quantitatively and comparatively analyzed by region using the results of the "Investigation on Biological Damage to Wooden Architectural Heritages" conducted by the National Research Institute of Cultural Heritage from 2016 to 2019. It involved 362 nationally designated wooden architectural heritages(25 national treasures, 157 treasures, 180 national folklore cultural heritages) and 1,104 buildings. The results were as follows: termite detection dogs reacted at 317(87.6%) of the 362 wooden heritages, with visible termite damage observed in 185 cases(51.1%). Furthermore, termite damage was confirmed using one of two methods(detection dogs or visual inspection) in 324 cases(89.5%). Of the 1,104 buildings, termite detection dogs reacted at 668(60.5%), while 339(30.7%) showed visible termite damage. Employing one of the two methods, damage was confirmed in 702 buildings(63.6%). The country was categorized into nine regions(Seoul Metropolitan Area, Gangwon, Chungbuk, Chungnam, Jeonbuk, Jeonnam, Gyeongbuk, Gyeongnam, and Jeju) to examine the termite damage rate and the degree of damage to each cultural heritage according to location. Termite detection dogs reacted to more than 70% of the cultural heritage in all regions. Visible damage was minimal in the Seoul metropolitan area(32.1%) and Gangwon(21.4%) but severe in Chungnam(65.6%), Jeonnam(67.3%), and Gyeongnam(68.2%). By quantifying the degree of termite damage of each cultural heritage as a ratio of the absence of termite damage among the total absence, the average termite damage of the cultural heritage across the country was 9.2%. Regional variance analysis showed that the cultural heritage in Jeonbuk and Jeonnam showed a statistically significantly higher degree of termite damage than the cultural heritage in the Seoul metropolitan area, Chungbuk, and Gyeongbuk. This paper comprehensively analyzed termite damage to nationally designated wooden architectural heritage. The findings are expected to be valuable in establishing policies for the preservation and management of cultural heritage sites in the future.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.25-31
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• 1974

1. Various gluing qualities applying Resorcinol Plyophen #6000 were studied on aiming the strength relationships of laminated woods resulted by single species [poplar (Populus deltoides), larch(Larix leptolepis)], mixed species of (poplar and larch), preservatives, treated poplar the scarf joint with mixed species of poplar and larch and the scarf joint treated with preservatives. 1. 1 On the block shear and on the DVL tension test, the mean wood failure ratio showed an excellent value i.e., above 65% and the tangential strength for larch was higher than that of radial, but it was reversed for poplar as shown in Tables 1 and 2. 1. 2 The lamina treated with Na-PCP reduced slightly the strength but the limited strength allowed for manufacturing laminated wood was not influenced by treating Na-PCP as shown in Tables 3 and 4. 1. 3 The safe scarf ratio in the plane scarf joint was above 1/12 for larch and 1/6 for poplar regard less of the chemical treatment or untreatment as shown in Tables. 5, 6, 7 and 8. 2. In the normal and boiled state, the gluing quality of the laminated wood composed of single[poplar (Populus deltoides), larch (Larix leptolepis)] and double species (poplar and larch) glued with Resorcinol Plyophen #6000 were measured as follow, and also represented the delamination of the same laminated wood. 2.1 The normal block shear strength of the straight and curved laminated wood (in life size) were more than three times of the standards adhesion strength. And, the value of the boiled stock was decreased to one half of the standard shear adhesion strength, but it was more than twice the standard strength for the boiled stock. Thus, it was recognized that the water resistance of the Resorcinol Plyophen #6000 was very high as shown in Tables 9 and 10. 2. 2 The delamination ratio of the straight and curved laminated woods in respect of their composition were decraesed, in turn, in the following order i. e., larch, mixed stock (larch+poplar) and poplar. The maximum value represented by the larch was 3.5% but it was below the limited value as shown in Table 11. 3. The various strengthes i.e., compressive, bending and adhesion obtainted by the straight laminaced wood which were constructed by five plies of single and double species of lamina i. e., larch (Larix leptolepis) and poplar (Populus euramericana), glued with urea resin were shown as follows: 3. 1 If desired a higher strength of architectural laminated wood composed of poplar (P) and larch (L), the combination of the laminas should be arranged as follows, L+P+L+P+L as shown in Table 12. 3.2 The strength of laminated wood composed of laminas which included pith and knots was conside rably decreased than that of clear lamina as shown Table 13. 3.3 The shear strength of the FPL block of the straight laminated wood constructed by the same species which were glued with urea adhesives was more than twice the limited adhesion strength, thus it makes possible to use it for interior constructional stock.

• Journal of agricultural medicine and community health
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• v.30 no.2
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• pp.183-204
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• 2005

Objectives: Immunization program is essential public health service under the national responsibility. One of the immunization service of national immunization program is advertising and public relation service, but research for that was rarely conducted. Therefore we conducted the survey for developing advertising strategy of immunization program in 21th century. Methods: Our study subjects were 242 health workers in immunization service department of 169 health centers and 1,193 carers who visited community health center for receiving immunization service of their children. The major questions were general characteristics of the subjects, perceived importance of immunization program, experience of advertising, knowledge and perception about immunization, and items about advertising strategy. Results: Frequently exposed materials in both health workers and carers were TV, community newspapers, and pamphlets. Health workers had high professional knowledges of immunization and carers had high perceptions for need and importance of immunization. Health workers preferred pamphlets and posters as advertising materials and carerers preferred TV and community newspapers. Both health workers and carers preferred green and yellow as advertising posters' color, active and healthy style of immunization advertising, and positive messages of campaign's slogans. Conclusions: Further researches should be conducted for precising long-term immunization advertising strategy in 21th century, and for this we need to develop advertising materials based on public needs and strategy, and evaluate the materials. The national immunization program should be activated throughout more investment of the budgets and human powers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.1064-1072
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• 2010

The objectives of this study were to gain an overview of practices and effect evaluation of oven utilization at school foodservice facilities in Daegu and Gyeongbuk province. Out of 147 dieticians, who responded for questionnaires, 44 dieticians used the oven and 103 dieticians did not use the oven. All statistical analyses were conducted with the SPSS 14.0 statistical software program. With regard to the style of foodservice system, 74.4% were urban, 23.3% were rural, and 2.3% were remote country. Also, 23.3% of school foodservices produced meals by batch cooking. According to the results of the expected effect and using effect analysis for 27 items, the average of evaluation score about expected effect was 1.64 points and that of using effect was 1.61 points. Both expected effect and using effect had higher scores than average points in 13 items out of 27 items. Using effect had higher scores than expected effect in 4 items. In conclusion, using ovens could help to increase foodservice satisfaction of students at school foodservice, because it can improve the various cooking methods and the food safety management. Therefore, it is important to modernize and automate cooking equipment for quality improvement of school foodservice operations.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.261-268
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• 2013

Purpose: The purpose of this study was to investigate the effect of geometrically different wax pattern shapes and sizes on the castability of Grade2 Cp-Ti (commercially pure titanium). Materials and methods: Total of 40 mesh wax pattern ($61mm{\times}24mm$, 207 grids), ($61mm{\times}17mm$, 138 grids) was cast in this experiment. Depending on the geometrical shape of the wax pattern, 8 groups was organized; Flat, Semicircular, Horse-shoe and V-shape, each consisting 5 samples. Runner-bar sprue was used in all patterns. The number of completely cast grid in wax pattern served as a measure for the castability of comercially pure titanium. Results: The mean value of square count in each group was as followed; 133.20 squares in group SS (96.52%), 132.40 squares in group SH (95.94%), 132.00 squares in group SF (95.65%), 127.60 squares in SV (91.43%), 198.60 squares in group LF (95.94%), 197.80 squares in group LV (95.56%), 196.40 squares in group LS (94.88%), and 188.00 squares in group LH (90.82%). Conclusion: Within the limitations of this study the results indicate that there were no sttistically significant difference in castability of titanium regarding wax pattern shape (P>.05). However, Small size wax patterns were showing the noticeable castability more than Large size pattern.

• Journal of the Korean GEO-environmental Society
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• v.15 no.1
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• pp.63-68
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• 2014

In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide ($TiO_2$), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were $TiO_2/HAP/Ge$ > $TiO_2/Ge$ > $TiO_2/HAP$. The composition of $TiO_2/HAP/Ge$ using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of $TiO_2$ ($X_1$), HAP ($X_2$) and Ge ($X_3$) which consisted of 6 condition in each variables was set up to determine the effects on LM ($Y_1$) and TOC ($Y_2$) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value ($R^2$ of $Y_1=99.28%$ and $R^2$ of $Y_2=98.91%$). Contour plot and response curve showed that the effects of $TiO_2/HAP/Ge$ composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal ($Y_2$) were $X_1=0.6913$, $X_2=0.2313$ and $X_3=0.0756$ by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model's predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.

• Journal of Korean Home Economics Education Association
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• v.19 no.1 s.43
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• pp.47-64
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• 2007

The purpose of this study was to develop, apply and evaluate the teaching learning plan for disabled experimental activity to evaluate the accessibility of middle school experimental facilities. Three main resources such as 2 hours teaching learning plan for disabled activity, recording sheets and evaluation sheets had been developed. The process plan had been applied 214 senior students in 7 middle schools purposely selected by areas, constructed years, number of stories of school during November to December, 2005. General accessible levels of middle school facilities was somewhat inadequate especially exterior slops, toilets, bowls were the most unaccessible ones. Most of all students had accidents and/or injuries in school environments from minor to major ones. Male Students were more likely than female Students to get injuries. Students experience of accidents and injuries and awareness of inconvenience, danger, needed facilities supported. the result of the accessibility levels evaluated by disabled activities. Students were generally satisfied with and positive to the teaching learning process plan developed and applied in this study. Students had improved critical Perspectives as well as awareness of inaccessible chances in the school facilities through the experimental process. The evaluation as differed by school characteristics and students' interests in disability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.466-476
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• 2006

The objective of this study was to compare and analyze the acceptability and consumption attitude for soy foods between Korean and Canadian university students as young consumers. This survey was carried out by questionnaire and the subjects were n=516 in Korea and n=502 in Canada. Opinions for soy foods in terms of general knowledge were that soy foods are healthy (86.5% in Korean and 53.4% in Canadian) or neutral (11.6% in Korean and 42.8% in Canadian), dairy foods can be substituted by soy foods (51.9% in Korean and 41.8% in Canadian), and soy foods are not only for vegetarians and milk allergy Patients but also for ordinary People (94.2% in Korean and 87.6% in Canadian). In main sources of information about soy foods, the rate by commercials on TV, radio or magazine was the highest (58.0%) for Korean students and the rate by family or friend was the highest(35.7%) for Canadian students. In consumption attitude, all of Korean students have purchased soy foods but only 55.4% of Canadian students have purchased soy foods, and soymilk was remarkably recognized and consumed then soy beverage and margarine in order. 76.4% of Korean students and 65.1% of Canadian students think soy foods are general and popular and can purchase easily, otherwise, in terms of price, soy foods were expensively recognized as 'more expensive than dairy foods' was 59.1% (Korean) and 54.7% (Canadian), and 'similar to dairy foods' was 36.8% (Korean) and 39.9% (Canadian). Major reasons for the rare consumption were 'I am not interested in soy foods' in Korean students (27.3%) and 'I prefer dairy foods to soy foods' in Canadian students (51.7%). However, consumption of soy foods in both countries are very positive and it will be increased.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.150-154
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• 2010

Purpose: Ejection fraction (EF) is one of the most important factors that evaluate heart function. Recently, according to echocardiography and myocardial perfusion SPECT, the number of gated blood pool scan (planar GBP) is declining. Measurement of left ventricular ejection fraction using gated blood pool SPECT (GBPS) is known as relatively correspond with echocardiography. We compared EF derived from plnar GBP, GBPS and echocadiography using modified simpson method to determine the accuracy. Materials and Methods: From January 2007 to June 2010, planar GBP and GBPS were performed on 34 patients who admitted to Pusan National University Hospital (men 23, women 11, mean age $52.6{\pm}27.2$). Each patient was injected with $^{99m}{TcO_4}^-$ of 20 mCi after pyrophosphate injection and then scanned using both planar GBP and GBPS techniques. For image analysis, we use ADAC Laboratories, Ver. 4.20 software. The result analyzed was processed by SPSS 17.0 Win statistic program and statistical method applied in data analysis is one-way anova, Tukey's post hoc test, pearson correlation test. Results: One-way anova test show no significant difference (planar GBP $56.3{\pm}13.9%$; GBPS $60.4{\pm}16.0%$; echocardiography $59.1{\pm}14.4%$, p=0.486, p>0.05). Tukey's post hoc test show no significant difference (planar GBP-echocardiography p=0.697; GBPS-echocardiography p=0.928; planar GBP-GBPS p=0.469, p>0.05). Values for EF obtained with planar GBP and GBPS correlated well with those obtained with echocardiography (planar-echocardiography r=0.697; GBPS-echocardiography r=0.928; planar GBP-GBPS r=0.469). Conclusion: The problems of accuracy and reproducibility for planar GBP still remain. But planar GBP is a safe and non-invasive method. In addition, planar GBP is useful to evaluate patient with low resolution echocardiography images. GBPS is not appicated clinically. but GBPS can be obtain various left ventricular functional parameters. planar GBP, GBPS and echocardiography show a good correlation between each other. Therefore, planar GBP and GBPS are useful for evaluating left ventricular ejection fraction.