• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.56-60
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• 2000

A new porous carbon material "woodceramics" was developed by carbonizing wood or woody materials impregnated with thermosetting resin. Steamed board and non-steamed board were made from thinned small log of Aomori Hiba (Thujopsis dolabrata S. et. Z. var. hondae M.). They were impregnated with phenol resin and sintered in a vacuum furnace at $650^{\circ}C$. In this paper, the manufacturing method of woodceramics and changes of dimension, weight and compressive strength were investigated. The changes of dimension, weight and compressive strength depend on the types of board and density.

• Journal of Korean Academy of Oral Health
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• v.43 no.3
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• pp.118-123
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• 2019

Objectives: The purpose of this study was to investigate changes in the composition of artificial cariogenic biofilms using a Streptococcus mutans biofilm model over a period of time. Methods: We analyzed the dry weight, colony forming unit (CFU) number, extracellular polysaccharide (EPS) biovolume, and acid production rate of S. mutans biofilms formed on saliva-coated hydroxyapatite discs after 26 h, 50 h, 74 h, 98 h, 171 h, and 195 h. In addition, we performed a laser scanning confocal fluorescence microscopy to determine the bacterial volume, EPS biovolume, and biofilm thickness. We calculated the biofilm density using dry weight and EPS biovolume. Results: Over a period of time, there was no change in the CFU number and acid production rate of S. mutans biofilms, but there was an increase in the dry weight and EPS biovolume of S. mutans biofilms. The bacterial volume, EPS biovolume, and biofilm thickness only increased in the 50-h-old biofilm; however, no change was observed in 50-195-h-old biofilms. In addition, an increase in the biofilm density was observed over time. Conclusions: These results suggest that the acid production ability of cariogenic biofilms does not change, but the biofilm density increases over time. However, due to scientific information, further research needs to be conducted in the field of dentistry to get further insights on the progression of cariogenic biofilms over time.

• Korean Journal of Community Nutrition
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• v.8 no.1
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• pp.33-40
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• 2003

This study was investigated the differences in the dietary habits and quality of diet among 148 university students in Daejeon between 1993 (71 subjects) and 2000 (77 subjects). Among male students, there were increases in height and decreases in weight, but the number in the normal weight group assessed by the BMI, increased. Significant increases in meal regularity and the rate of considering a balanced diet at meal time and significant decreases in the rate of eating unbalanced meals were noted over time among the male students. The number of male students drinking alcohol and those drinking alcohol frequently decreased significantly. When considering differences in the nutrient intake of males according to the Korean RBA, the percentages of energy, iron, and Vitamin B$_2$ decreased, while those of Vitamin C, calcium, and phosphorus increased over time. The NAR (Nutrient Adequacy Ratio) of most nutrients, especially in iron and Vitamin C were higher, than those of 1993, but the NAR of calcium, iron, Vitamin B$_2$, niacin and MAR (Mean Adequacy Ratio) were lower than 0.75 in the males. The INQ (Index of nutritional quality) of Vitamin C was higher than that of 1993, and the mQ of calcium and Vitamin $B_2$ were lower than 1 among the males. Among the females, there was no change in height and weight between 1993 and 2000, but the normal weight group, as assessed by the BMI, increased as among the males. However, unlike among the males, significant decreases in meal regularity and significant increases in the rate of alcohol drinking were noted over time. The intake of energy and nutrients showed trends similar to those among the males. The NARs of most nutrients were lower than those of 1993 among in the females. The INQs of protein, calcium, Vitamin $B_1$ and Vitamin C increased significantly, but the INQs of calcium, iron, and Vitamin $B_2$ were lower than 1 among the females. From these results, we found that male students showed relatively desirable changes over time in their dietary and health-related habits and the quality of their diets, while female students showed undesirable changes in their dietary and alcohol drinking habits and the quality of their diets.

• Journal of Conservation Science
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• v.20
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• pp.81-88
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• 2007

For the conservation of wooden coffin from King Muryeong's Tomb we examined weight change, shrinkage rate, color changes, and permeation expansion according to the permeation pretreatment chemicals by producing experimental samples with similar physical properties. The result shows Dammar 2 %(in xylene) as the most excellent treatment for protecting deformation by contraction and strengthening materials which are also maintaining its original colors of wood. Therefore, we could get strengthening conservation treatments of dried wooden coffin materials by using Dammar.

• Journal of Information Processing Systems
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• v.11 no.4
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• pp.630-642
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• 2015

In Jøsang's subjective logic, the fusion operator is not able to fuse three or more opinions at a time and it cannot consider the effect of time factors on fusion. Also, the base rate (a) and non-informative prior weight (C) could not change dynamically. In this paper, we propose an Improved Subjective Logic Model with Evidence Driven (ISLM-ED) that expands and enriches the subjective logic theory. It includes the multi-agent unified fusion operator and the dynamic function for the base rate (a) and the non-informative prior weight (C) through the changes in evidence. The multi-agent unified fusion operator not only meets the commutative and associative law but is also consistent with the researchers's cognitive rules. A strict mathematical proof was given by this paper. Finally, through the simulation experiments, the results show that the ISLM-ED is more reasonable and effective and that it can be better adapted to the changing environment.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.2
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• pp.69-74
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• 2010

Feeding is an important aspect of insect nutrition which in turn supports growth, development, reproduction and survival. The impact of quantitative feeding on nutritional parameters of fifth instar Antheraea mylitta larvae was studied by providing fresh leaves of Terminalia tomentosa for 1 to 4 times a day. All the parameters improved upon providing fresh diets more times over the single diet (1FD). The absolute body weight increased with increase in number of feeds/day significantly (P<0.001). While the maximum weight recorded was 29.61 g in 1FD, the respective weights for two feeds/day (2FD), three feeds/day (3FD) and four feeds/day (4FD) were 39.41 g, 40.63 g and 42.66 g respectively. Feeding period and instar duration were declined (P<0.001) and survival increased significantly (P<0.001) upon increase in the number of diets. Nutritional indices like ingestion, digestion, relative consumption rate (RCR), relative growth rate (RGR) and gain in body weight increased significantly with the increase in number of feeds/day, but approximate digestibility (AD) and efficiency of conversion of ingested food (ECI) declined, while efficiency of conversion of digested food (ECD) did not change.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.18-23
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• 1990

Seven varieties of soybeans(Paldal, Danyeob, Jangbaek, Baegun, Jangyeob and 2 cultivars of Local 1 and Local 2) were investigated to compare the water uptake properties and volume changes during soaking in water. The hydration properties showed that the equilibrated weight increase ratio decreased as the soaking temperature raised to higher than $40^{\circ}C$, while the initial water uptake rate increased upto $80^{\circ}C$. The increase in hydration showed a linear relationship with the square root of the soaking time at $4^{\circ}{\sim}60^{\circ}C$. Local 1 was the highest in water uptake rate constant while Local 2 was the lowest. The activation energy calculated was in the range of $3,246{\sim}4,694\;cal/mole$. The Jangbaek and Local 1 were the highest and the Paldal was the lowest in the rate of volume increase. The activation energy for volume increase was in the range of $3,310{\sim}4,190\;cal/mole$. The z-values calculated from volume change was a little higher than those obtained from weight change.

• The Journal of Korean Society for School & Community Health Education
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• v.24 no.4
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• pp.51-60
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• 2023

Objectives: This study attempted to examine the factors that affect the national health checkup rate of the elderly, analyze the impact of these factors, and discuss countermeasures to problems that may arise based on this. Methods: This study used the '8th National Health and Nutrition Examination Survey (2019-2021)', a nationwide survey, as the main data. The subjects of the study are seniors aged 65 years or older, the dependent variable is whether or not they underwent a national health checkup, and the independent variables are gender, marital status, residence, education level, income level, economic activity, type of medical coverage, private insurance subscription, subjective health, High blood pressure, diabetes, depression, stress, and weight change were selected. The statistical analysis package for data analysis is SPSS ver. 27.0 was used, and a p value of less than 0.05 was considered significant. Results: Of the 2,806 seniors aged 65 years or older, 2,074 (73.9%) took the national health screening over the past two years. In terms of marital status, married was 1.451 times higher than single (p<0.001), and in terms of residence, myeon was 1.240 times higher than dong (p<0.01). In terms of education level, college graduates were 2.053 times higher than elementary school graduates (p<0.001), and in terms of economic activity, the employed were 1.325 times higher than the unemployed (p<0.01). Private insurance was 1.883 times higher than non-subscription (p<0.001), weight change was 1.234 times higher for change than no change (p<0.05), and current smoking rate was 2.003 times higher for non-smokers than for former smokers. It was high (p<0.001). Conclusion: In conclusion, if differentiated promotion and health education are strengthened for the elderly who cannot participate in the national health screening, the participation rate of the elderly in the national health screening is expected to increase.

• Food Science and Preservation
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• v.11 no.1
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• pp.7-11
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• 2004

To examine the effect of storage condition on the quality and microbiological change of strawberry “Minyubong”, the rate of weight loss, decay rate, pH and titratable acidity, and microbial (total bacterial count, mold and yeast) changes were determined during storage. Strawberry fruits were packaged with low-density polyethylene (LDPE). Strawberries were then stored at 4$^{\circ}C$ and 20$^{\circ}C$, respectively. LDPE package was effective on the decrease of decay rate of strawberry as well as the rate of weight loss, compared with the non-packaged. Microbial changes of strawberry stored at 4$^{\circ}C$ and 20$^{\circ}C$ were monitored during storage. Packaging affected the microbial change, resulting in retarding the growth of total bacteria as well as mold and yeast, compared with the non-packaged, regardless of storage temperature. These results indicate that storage of strawberry fruits wrapped with LDPE at 4'C should be recommended in terms of quality as well as its shelf-life.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.3
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• pp.62-68
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• 2003

In this study, an experimental work was performed to mold tensile specimens by using the injection molding machine. Melt temperature, mold temperature and the mixed rate of recycled resin were selected as processing parameters for studing the effect of those condition on the shrinkage and weight of molded parts. As a result, the shrinkage was increased with the higher mold and melt temperature and It was more senstive to the change of mold temperature. On the other hand, the weight of molded parts was decreased with the increment of mold and melt temperature.