• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.5-7
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• 1974

1. This study indicates that above the fiber saturation point the drying rate can be increased with increasing the velocity of the air circutation, i.e., the drying rate of sample boards is proportional to the air velocity, but below the fiber saturation point, the effect of the velocity of air circulation is very low as shown in Figs. 1 and 2. 2. Under the controlled temperature and humidity in the kiln, the more the sample boards have moisture, the higher drying rate of it can be obtained. In other words, this means that even though in the case of drying various moisture content of wood, at the final drying stage, approximately the same percentage of moisture content of wood can be secured by employing the higher velocity of air circulation. 3. This study shows that the rate of drying in kiln changes distinctly at the fiber saturation point, i, e., above the fiber saturation point, the drying curve shows concave aginst the X axsis, but below the fiber saturation point, in the range from 30 percent of moisture content to 20 percent of moisture content, the curve shows convex as shown in Fig. 3. As the drying progresses, however, the drying curve shows concave again below 20 percent of moisture content. This means that inflection point of drying curve may be located clearly at the fiber saturation point, i.e., 30 percent of moisture content. As mentioned above, the 30 percent of moisture content of wood at which the inflectional point appears can be recognized as a critical point, i. e., the fiber saturation point at which all free water was removed from wood. The existence of inflectional point indicates that the evaporation of hygroscopic water in a cell wall is more difficult than the evaporation of free water in a cell cavity and the minor space of cell wall. The convex curve in the range of moisture content from 30 percent to 20 percent means that the evaporation of capillary condensed water has a tendency of the same rates of drying approximately, but as approaching to the 20 percent of moisture, the transfusion of moisture from wood becomes difficult because of having less moisture in cell wall. Below 20 percent of moisture content, the drying curve shows concave again, which means that it is difficult to remove the moisture located nearer to the surface of cellulose molecules and the surface bound water. These relations were revealed in Fig. 4. In comparison AC curve which does not have the two inflection points with BD curve which has two inflection points, i.e., Band D, they are mentioned already, by existence of the inflection points, the curve BD shows that the change of drying rate in the interval from 20 percent of moisture content to 30 percent of moisture content is not greater than in the case of the curve AC in the same interval. At the inflection point of 30 percent of moisture content, it can be noticed that the changing of the drying rate is very conspicuous. This phenomenon also can be recognized, as it is noticed by the Fig. 3, the drying rate from green to 30 percent of moisture content is very great. But the inclination of the curve is very slow from 30 percent of moisture content to 20 percent of moisture content, i.e., the inclination of the curve becomes almost horizontal lines. Acknowledgments Gratitude is expressed to Fred E. Dickinson, Professor of 'Wood Technology, School of Natural Resources, University of Michigan, USA for his suggestion to carry out this study.

• Clinical and Experimental Pediatrics
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• v.49 no.1
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• pp.24-28
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• 2006

Purpose : The purpose of this study was to investigate the health status and nutritional condition of children living in a low-income community through anthropometric, laboratory evaluation. Methods : A community-based survey identified children below 15 years living in a low-income community. Their weight, height, visual acuity, hearing level and dental status were measured. Blood sample were obtained on June and July, 2004. Hemoglobin, serum cholesterol, Hepatitis B antigen/antibody, AST and ALT were measured. Results : A total of 285 students(M : F=141 : 144) aged 6 to 14 years were included in this study. The heights and weights in some grades were smaller than controls. The prevalence of obesity was 10.6 percent in males and 10.7 percent in females. The prevalence of abnormal visual acuity, hearing impairments and dental carries were 20.5 percent, 0.3 percent and 69.4 percent. The prevalence of anemia was 10.1 percent. Serum total cholesterol was over 200 mg/dL in 7 percent. They complained of abdominal pain(22.1 percent) and headache(17.1 percent). Hyperthyroidism, cataract, neurofibromatosis, severe atopic dermatitis, ventricular septal defect, strabismus and inguinal hernia were newly diagnosed. Conclusion : Mean heights and weights of children in the low-income community were smaller than controls. The prevalence of abnormal visual acuity, hearing impairment and dental carries were higher than in the 2003 national health survey. Additional research is needed to evaluate the health status of the low-income community.

• Korean journal of communication and information
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• v.44
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• pp.76-107
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• 2008

The present study has explored the effects of media use on the evaluation of the presidential candidate's morality. We hypothesized that the perception of the candidates' morality during the 2007 Korean President Election would be influenced by the amount of the different types of media use. Using a set of panel data, a total of 1,199 citizens (584 females (48.7%), 615 males (51.3%), Mage=42.77, SDage=13.34) were assessed four times from August to December in 2007. The results indicated that (a) the level of TV use for political information, the level of newspaper use for political information, and the level of Internet use for political information increased during the five months; (b) the initial level of political involvement contributed differently to the initial levels of media use; (c) the initial level of political involvement negative influenced the initial level of TV use for political information; (d) the growth of political involvement positively influenced the growth of TV use for political information; (e) the intial level of TV use for political information increased both the initial levels of the perception of candidates' morality and the change of the perception of candidates' morality; (f) the change of TV use for political information negatively affected the perception of candidates' morality; and (g) the initial level of Internet use for political information negatively affected the initial level of the perception of candidates' morality, and the change of Internet use for political information negatively affected the perception of candidates' morality.

• Journal of agriculture & life science
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• v.43 no.1
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• pp.51-59
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• 2009

The chemical components and antimicrobial activities of garlic from different area were investigated and analyzed to provide basic data for functional food materialization and processing. Hunter's values of garlic from different area were L 53.41~57.15, a -3.49~-4.38 and b 11.47~17.55. The moisture, crude protein, crude fat, nitrogen free extract, crude fiber and ash were 65.24~71.96, 6.24~9.35, 0.21~0.49, 19.01~22.72, 0.58~0.95 and 1.01~2.01%, respectively. The major minerals of garlic from different area were Na(27.22~112.03), Mg(18.17~32.56), K(242.16~569.28), Ca(28.60~63.93), P(117.72~265.21 mg%) and major free sugars were sucrose, glucose and fructose. The major amino acids of garlic from different area were proline, arglmne, glutamic acid and aspartic acid and content of total amino acid was 2,709.33~4,561.04 mg%. The ascorbic acid content of garlic from different area was 2.966~8.673 mg%. Composition of fatty acids of garlic from different area were linoleic acid, oleic acid and palmitic acid, unsaturated fatty acid and saturated fatty acid contents were 72.18~74.35 and 25.65~27.82%, respectively. Antimicrobial activities of garlic extracts as different area increased depends on concentration and showed the high antimicrobial activities against Gram(+) and Gram(-).