• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.24-33
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• 2020

In excavated bronze artifacts, corrosion products of various shapes and colors are observed due to multiple corrosion factors coexisting in the burial environment, and these corrosion products can constitute important data not only in terms of long-term corrosion-related information, but also in connection with preservation of artifacts. As such, scientific analysis is being carried out on the corrosion layer and corrosion products of bronze artifacts, and the corrosion mechanism and the characteristics of corrosion products elucidated, which is essential for interpreting the exposed burial environment and its association with corrosion factors inside the burial environment. In this study, after classifying excavated bronze artifacts according to alloy ratio and fabrication technique, comprehensive analysis of the surface of corrosion artifacts, corrosion layer, and corrosion products was carried out to investigate the corrosion mechanism, formation process of the corrosion layer, and characteristics of corrosion products. The study designated two groups according to alloy ratio and fabrication technique. In Group 1, which involved a Cu-Sn-Pb alloy and had no heat treatment, the surface was rough and external corrosion layers were formed on a part, or both sides, of the inside and the outside, and the surface was observed as being green or blue. α+δ phase selection corrosion was found in the metal and some were found to be concentrated in an empty space with a purity of 95 percent or more after α+δ phase corrosion. The Cu-Sn alloy and heat-treated Group 2 formed a smooth surface with no external corrosion layer, and a dark yellow surface was observed. In addition, no external corrosion layer was observed, unlike Group 1, and α corrosion was found inside the metal. In conclusion, it can be seen that the bronze artifacts excavated from the same site differ in various aspects, including the formation of the corrosion layer, the shape and color of the corrosion products, and the metal ion migration path, depending on the alloy ratio and fabrication technique. They also exhibited different corrosion characteristics in the same material, which means that different forms of corrosion can occur depending on the exposure environment in the burial setting. Therefore, even bronze artifacts excavated from the same site will have different corrosion characteristics depending on alloy ratio, fabrication technique, and exposure environment. The study shows one aspect of corrosion characteristics in specific areas and objects; further study of corrosion mechanisms in accordance with burial conditions will be required through analysis of the corrosive layer and corrosive product characteristics of bronze artifacts from various regions.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.380-387
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• 2001

The characteristics of ecological niche, breadth and overlap, for seventeen major tree species were evaluated in the natural deciduous forest in Mt. Chumbong area. Employed by the plot sampling method, the environmental gradient for vertical niche was based on the intensity of light within the forest, and that for horizontal niche was based on multi-dimensional resources in distribution pattern. The result showed that Fraxinus rhynchophylla had the highest value of vertical niche breadth and Maackia amurensis had the lowest, and Acer pseudo-sieboldianum had the highest value of horizontal niche breadth and Betula costata had the lowest. There was no significant correlation between both measures of niche breadth. However, the tolerance index for each species was positively correlated to the values of niche breadth. Spearman's rank correlation coefficients were applied to test the correlationship between the species ranks of tolerance index and those of two ecological niche breadths. The coefficient of $r_s=0.432$ ($P{\leq}0.1$) was not enough to support significant correlationship between the tolerance index and vertical niche breadth at the 95% probability. If Carpinus cordata, rarely reach canopy of the forest due to its own growth form, are excluded from the analysis, coefficient was calculated as $r_s=0.650$ ($P{\leq}0.01$), resulting in highly significant correlationship. The Spearman's rank correlation coefficient was $r_s=0.797$ ($P{\leq}0.01$) for tolerance indices and the values of horizontal niche breadth, indicating highly significant. Four distinctive species groups, produced by cluster analysis on the basis of ecological niche overlap for each pair of species, were in considerable accord with the positively associated species constellation pattern created by the inter-species association analysis.

• Korean Journal of Cognitive Science
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• v.15 no.4
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• pp.31-47
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• 2004

This study was carried out to examine the development of physical knowledge in children. Eighty children aged 3- to 11-year-old and 16 adults were participated in this study. Participants' knowledge about failing, sliding and sinking/floating objects was investigated to understand what kind of knowledge they had, whether their knowledge was organized as theory and what was the nature of the developmental change in physical knowledge. Results showed that, for falling object task children of all age had correct knowledge about object's falling phenomena. However, there were age differences in children's understanding of the cause of object's falling. As the children's age decreased, the frequency of explanation referring to the absence of supper rather than the gravity as the cause of falling phenomena increased. For the sliding object task, children of all age could predict the motion of sliding object correctly. But only a few 9- and 11-year-old children could understand the effect of object weight and relations between gravity, frictional force and their interactions. Children under age 7 showed no evidence of possessing these knowledge. For sinking or floating object task, children of all age and even adults showed difficulties in understanding the sinking or float phenomena per se. For the cause of these phenomena although a few 9- and 11-year-old children referred to buoyancy as the cause, they had no correct knowledge about the buoyancy. This was also true for the adults. As a conclusion, the results of this study suggested that, not 3, but as young as 5-year-old children's physical knowledge exited as a form of naive theory in terms of their use as a causal devise in explaining the cause of object motion. However, even the theory of 9- and 11-year-old children was lack of the abstractness and coherence, which were also important characteristics of a theory. Finally, developmental change in physical knowledge proceeded toward more frequent and consistent use of physical knowledge as causal device and more abstract and coherently organized theory.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1336-1343
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• 2005

In the present study, we screened candidates for enhancing insulin action and secretion from Cinnamomum camphora (CC) fractions, in 3T3-L1 adipocytes and Min6 cells by investigating insulin- stimulated glucose uptake and glucose-stimulated insulin secretion, respectively. CC were extracted by $70\%$ ethanol followed by XAD-4 column chromatography with serial mixture solvents of methanol and water, and the fractional extractions were utilized for determining insulin action and secretion, and $\alpha$-glucoamylase suppressing activity, A significant insulin-stimulated glucose uptake was observed in 3T3-L1 adipocytes, giving 0.5 or $5{\mu}g/mL$ of $40\%\;and\;60\%$ methanol fractions plus 0.2 nM insulin, compared to the treatment of DMSO plus 0.2 nM insulin. The treatments of $40\%\;and\;60\%$ methanol fractions plus 0.2 nM insulin reached the glucose uptake of 10 nM insulin treatment. The $40\%$ methanol fraction increased triglyceride accumulation by stimulating differentiation and triglyceride synthesis similar to pioglitazone, PPAR-$\gamma$ agonist. No inhibition of $\alpha$-glucoamylase activity of CC fractions was observed. They did not modulate the insulin secretion capacity In either low or high glucose media. These results suggest that $40\%$ methanol fraction contains a potential insulin sensitizer to have a similar function of PPAR-$\gamma$ agonist. Crude CC extract may improve glucose utilization by enhancing insulin-stimulated glucose uptake without elevating glucose stimulated insulin secretion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1422-1430
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• 2015

This study was conducted to determine the effect of fermented water extracts from Ligularia fischeri (LAF) on reduction of hepatotoxicity induced by D-galactosamine (D-GalN) in rats. In this experiment, male Sprague-Dawley rats were used as experimental animals, which were divided into eight groups: normal group, D-GalN-treated group (control), D-GalN and non-fermented water extracts from Ligularia fischeri (LA)-treated groups [100, 200, and 400 mg/kg BW (body weight)], and D-GalN and LAF-treated groups (100, 200, and 400 mg/kg BW). ${\gamma}$-Glutamyl transferase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase activities in serum of the D-GalN and LAF-treated groups decreased significantly compared to those of the control group (P<0.05). The high density lipoprotein-cholesterol levels of the D-GalN and LAF-treated groups increased significantly compared to those of the control group (P<0.05). The low density lipoprotein-cholesterol and triglyceride levels of the D-GalN and LAF-treated groups decreased significantly compared to those of the control group (P<0.05). The atherogenic index values of the D-GalN and LAF-treated groups decreased significantly compared to those of the control group (P<0.05), and their high density lipoprotein cholesterol by total cholesterol ratio increased significantly in these groups (P<0.05). Superoxide dismutase activity of liver tissues were enhanced significantly (P<0.05) in the D-GalN and LAF-treated groups compared to that of the control group (P<0.05), whereas their malondialdehyde content decreased significantly in these groups (P<0.05). The histopathological observations revealed apoptotic cells and mild portal inflammation in liver tissues of the D-GalN and LAF-treated groups. Taken together, these results demonstrate that LAF may improve plasma lipid profile and alleviate hepatic damage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1431-1438
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• 2015

This study was conducted to determine the effects of fermented water extracts from Ligularia fischeri (LAF) on reduction of hepatotoxicity induced by ethanol in rats. Ethanol-treated Sprague-Dawley rats were divided into the following eight groups: ethanol-treated group (control), ethanol and ursodeoxycholic acid-treated group (positive control), ethanol and non-fermented water extracts from Ligularia fischeri (LA)-treated groups [100, 200, and 400 mg/kg BW (body weight)], ethanol and LAF-treated groups (100, 200, and 400 mg/kg BW). ${\gamma}$-Glutamyl transferase activities of the ethanol+LA-treated (100, 200, and 400 mg/kg BW) groups and ethanol+LAF-treated (400 mg/kg BW) group decreased significantly compared to those in the control group (P<0.05). Aspartate aminotransferase activities of the ethanol+LAF-treated (100, 200, and 400 mg/kg BW) groups and ethanol+LA-treated (200 and 400 mg/kg BW) groups decreased significantly compared to those in the control group (P<0.05). Alanine aminotransferase and lactate dehydrogenase activities of all groups significantly decreased compared to those in the control group (P<0.05). The total cholesterol, low density lipoprotein-cholesterol, and triglyceride levels of all groups tended to decrease compared to those in the control group, but the differences were not significant. Superoxide dismutase activity of liver tissues was enhanced in the ethanol+LAF-treated (400 mg/kg BW) group (P<0.05). The contents of malondialdehyde in liver tissues decreased in the ethanol+LAF-treated groups (P<0.05). All treated groups showed well preserved lobular architectures with no evidence of steatosis or liver damage compared to the control group. As the results of this study, LAF may improve the plasma lipid profile and alleviate hepatic damage by ethanol.

• Journal of Korean Physical Therapy Science
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• v.5 no.3
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• pp.659-674
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• 1998

This Study was to investigate elaborated research themes and direction through specifying the problems of clinical practice education and looking for the direction of improvement. It was in the basis of the viewpoint of the educators that professors and therapists who were the subjects of this study. Perform this study, the 15 colleges' professors and the 55 hospitals' therapists was made up questionnaire, and the data was analysing by Chi-square test and percentage. The results were as follow : ${\cdot}$ In a personal history among the general qualities, professors have little clinical practice history(l-5 years, 53.3%), and therapists have little lecture career(1-5 years, 43.6%, have no 49.0%), ${\cdot}$ The 78.6% subjects were unsatisfied of clinical practice systems. ${\cdot}$ The correlation between clinical history, school career and lecture career and the satisfaction level of clinical practice systems has no(P<.005), ${\cdot}$ The subjects were agreed to that clinical practice curriculum should be changed(67.1%), reinforced(82.9%), and specified(90.0%). ${\cdot}$ The clinical practice credits are 11 points averagely. ${\cdot}$ In the clinical practice curriculum, it made no difference in the practicum of diseases, modality, and the therapeutic techniques between professors and therapists. ${\cdot}$ The 100% professors said that the practicum of the patients' assessment is necessary, and the 63.6% therapists were training for that. ${\cdot}$ The 66.7% professors said that the practicum of the clinical psychology is necessary, and only the 20.0% therapists were training for that. ${\cdot}$ The 93.3% professors said that the practicum of the patients' management is necessary, and the 50.9% therapists were training for that. ${\cdot}$ The 66.7% professors said that the practicum of the medical ethics is necessary, and the 34.5% therapists were training for that. ${\cdot}$ The 46.7% professors said that the practicum of the hospital administration is necessary, but the 54.5% therapists have not training. ${\cdot}$ The 33.3% professors said that the practicum of the pharmacology is necessary, but the 81.8% therapists have not training. ${\cdot}$ The 86.7% professors said that the practicum of the patient's education is necessary, and the 43.6% therapists have training. ${\cdot}$ The 66.7% professors said that the practicum of the prosthesis and brace is necessary, but the 14.5% therapists have not training. ${\cdot}$ The 60.0% professors said that the practicum of the exercise prescription is necessary, but the 25.5% therapists have not training. ${\cdot}$ The 53.5% professors said that the practicum of the emergency treatment is necessary, but the 52.7% therapists have not training. ${\cdot}$ Drawing up the plan about the curriculum of clinical practice, the professors (46.7%) were agreed to national master plan framing by an expert advisor, but the therapists (58.2%) said that the plan that make the most of hospitals' characteristics should be specified. ${\cdot}$ It was found that a clinical special therapists(54.5%) was good as a person in charge of clinical practice education, in that each therapist's own good time (34.5%) was. ${\cdot}$ It made use of the form framing by college(40.0%) as the clinical practice textbook, the form framing by hospital (42.9%) and each therapist(22.9%) as the plan, and the form framing by college (74.3%) as the measurement. ${\cdot}$ The most difficult point in clinical practice education was the lacks of the theory-praciticum linkage(78.2%). ${\cdot}$ It was found that the period of clinical practice was in the second semester-third grade (40.0%) and the desirable period was in the first semester-third grade(50.0%). ${\cdot}$ Professors (53.3%) were agreed that the desirable clinical practice duration was from four months to six months(60.0%), and the therapists (60.0%) were agreed that from one month to three months. ${\cdot}$ This study presented the lacks of rearing the experts, the lacks of cultural education, and the lacks of the theory-clinical practice linkage. There were need to develop the systematic programs, clinical practice textbooks, the measurements and the special hospital for clinical practice. And it was need to reduce the gab between of the hospitals for clinical practice, to cut down the costs. and to improve the labour conditions of leaders. In view of this findings, it takes notice of that both professor and therapist were dissatisfied at the present clinical practice systems. These results point out the problems of clinical practice systems, and do not make expect to us the successive and positive clinical practice. The general, specific and intensive plan about the problems and the direction of improvement that establishing the level of hospital for clinical practice and physiotherapy can be elaborated.

• Journal of Korean Physical Therapy Science
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• v.1 no.1
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• pp.135-144
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• 1994

The authors studied therapeutic effects and related clinical data retrospectively on a series of 48 consecutive patients with head injury who were referred to physical therapy and occupational therapy, Kosin University Medical Center during 1 year, from March, 1993. through March, 1994. The conclusions were as follows : 1. Average age of the subject patients was 50.6 years, their age remped from 14 to 72 years, and the incidence between male and femele was 1:1.1. 2. In respect to the educational level high school graduates showed the highest incidence 18 (39.1 %) of 46 cases, and in respect to economy level, middle class revealed the highest incidence, 31(64.6 %) in 48 cases. 3. The HBP was the most common cause of spontaneity injury, disclosing 19 cases in 35 patients(54.3%), whereas the main cause of traumatic injury was a traffic accident, 7 cases ( 53.8 %) in 13 patients. 4. As for the region of injury in the cases of spontaneity ICH was 14 persons (40%). In the cases of trauma, hematoma was seen in 6 cases(42.2 %) in 48 total cases ICH was seen in 17 cases (35.4 %) to be the most common region. 5. Among 35 persons, spontaneity CBR was the highest region of injury, 13 cases(37.1 %) ; the side of paralysis in extremities the right side showed higher incidence, 18 cas (1.4 %) as compared to the left, 16 cases(45.7%). In the case of traumatic injury, CBR was the highest region of injury, 4(30.8% )in 13 cases and as for the paralysis side, right side showed higher incidence 7 cases(53.8%) as compared to the left side 5 cases(38.5%). 6. In respect to recurrence, HBP was seen in 5 cases to be the most common cause, and as for the region of injury, CBR was the highest. 7. A period of rehabilitation therapy in the cases of physical therapy the highest term was 1-2 month, 14 persons(29.2%). As for occupational therapy within 2 week-term was the highest, 24 persons(50%). 8. Physical strenth grade M.T in the cases of the upper extrimities before therapy, the low mark(grade 0) was 30 cases(62.5%), compared to the high mark(above grade 3)seen in 1 case(2.1%), And after therapy, the lowest mark(grade 0)was seen in 5 cases(10.4%) where as the high mark(above grade 3)was seen in 29 cases(60.4%). In the case of the lower extremities before therapy, the mark(below grade 1)was 37 cases(77.1 %), while the high mark(above grade 3)was seen n 4 cases(8.4%). And after therapy the low mark(below grade 1)was seen in 5 cases (10.4 %) and the high mark (above grade 3)was seen in 29 cases(60.4 %). 9. Before therapy conigtive function-level evaluation utilized R.L.A.L, the low mark(below level 3)was seen in 9 cases(18.8%), while the high mark(above level 7)was seen in 18 cases(37.5%). And after therapy the low mark (below level 3)was 4 cases(8.3%) and high mark(above level 7)was seen in 38 cases(79%). 10. After rehabilitation therapy, patients who were able to walk independently were 29 persons(60.4%), among which 16 cases(55.2%) depended on cane. The ratio between the cases who were able to walk and unable to walk was 1.5:1.

• Journal of the Korean Applied Science and Technology
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• v.37 no.1
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• pp.17-27
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• 2020

The purpose of this study is to confirm the effects of a 6-week high-intensity combined training program on canoe athletes' cardiorespiratory function, isokinetic trunk strength, and anaerobic power. For the purpose of this study, the high-intensity combined training program was applied to 9 high-school canoe athletes. The high-intensity combined training program consists of aerobic exercise performed 2 times a week (Tuesday and Thursday), anaerobic exercise performed 3 times a week (Monday, Wednesday, and Friday), and flexibility exercise performed 5 times a week. The core of the high-intensity combined training program was the anaerobic training program performed with 100% weight for repetition; otherwise, the existing training method was divided into the percentage (%) of the 1RM. The aerobic exercise and the gym ball exercise are performed subsidiarily. Results showed that there was a statistically significant difference in height and muscle mass, whereas there was no statistically significant difference in weight, body fat percentage, and BMI followed by the high-intensity combined training program. There were statistically significant differences in maximum oxygen uptake and total exercise time. The angular velocity of 30°/sec showed a statistically significant difference in the peak torque item of flexors only. Also, the angular velocity of 120°/sec showed a statistically significant difference in the total work item of extensors only; however, there was no statistically significant difference in all the items of peak power, average power, and peak drop. In conclusion, it seems that the high-intensity combined training program may be applied as a training program for enhancing canoe athletes' performance. For further studies, more than 6 weeks training program with more participants would show improved results of isokinetic strength and anaerobic power in athlets.

• Korean Journal of Poultry Science
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• v.21 no.3
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• pp.157-168
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• 1994

This study was carried out to elucidate the time course variation of vitamin $D_{3}$ (V$D_{3}$) and 25-hydroxyvitamin $D_{3}$ [25(OH)$D_{3}$] contents in the liver and skeleton of 3-wk old broiler chicks when treated with different UV irradiation procedure. Day-old Hubbard chicks were fed vitamin D deficient diet for 3 wk and exposed to medium wave ultraviolet(UVB) light with different irradiation procedures. Procedure I was 30 min continuous irradiation(O.204 mJ /$cm^{2}$) and Procedure II was three seperate 10 min irradiation with 12 h intervals, and Procedure III was three seperate 10 min irradiation with 24 h intervals. The liver and skeleton samples were collected at 10 different times between 0000~2400 h after the last irradiation. The V$D_{3}$ and 25(OH)$D_{3}$ fractions wereseparated by Sep-Pak silica cartridge and the concentrations were determined by normal phase HPLC. The mean content of V$D_{3}$ in the liver of the birds treated by Procedure II was 6.68 ng /g, which was higher than 5.60 and 5.30 ng /g from Procedure I and Ill, respectively(P<.O5). With regard to the effect of elapsed time after UVB irradiation on the V$D_{3}$ concentration of the liver, 96 h treatment showed the highest value(13.08 ng/g)(P<.05). There was a significant(P$D_{3}$ were significantly(P$D_{3}$ in the skeleton of tibia and femur, there were no significant differences among Procedure I, II and III, but significant differences were found among those from various elapsed time after irradiation, The highest value was shown at 96 h(O.99 ng /g) treatment, and interaction between irradiation procedure and elapsed time was not significant. With regard to the mean content of 25(OH)$D_{3}$ in bone, the Procedure II(18.79 ng /g) and III(17.73 ng /g) showed higher values than Procedure I did (P<.05), and the 12 h elapsed time showed the highest value(31.17 ng /g) among 10 treatments (P<.05), however, there was no significant interaction between exposing procedure and elapsed time. In conclusion, the Procedure II would he more desirable than Procedure I or III to produce more V$D_{3}$ and 25(OH)$D_{3}$ in the liver and skeleton of birds by exposing to the UVB light. Also, it was verified that 25(OH)$D_{3}$ increases more quickly than V$D_{3}$ in both tissues tested and is utilized more quickly to recover from the rickets of chicks.