• Journal of the Korean Ceramic Society
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• v.31 no.12
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• pp.1507-1512
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• 1994

High strength cement hardened body was prepared by ordinary portland cement, silica-fume, super-plasticizer and the industrial by-product powder such as tailing, paper sludge ash and granulated slag. These raw materials were mixed and formed with w/c=0.18. The cement hardened body is cured in the autoclave at 18$0^{\circ}C$, 10atm. These admixtures made the compressive strength of all specimens develope by 170~230%. The highest compressive strength could be obtained by 236 MPa when mix composition was 14 wt% of silica-fume and 26 wt% of granulated slag. The compressive strength increased with decreasing the average pore size and the amount of the poe over the size of 50 nm by which the appearance of high compressive strength of the cement hardened body were mainly influenced. In the result, the hydration products were C-S-H, tobermorite and ettringite and it was realized that the reason why the cement hardened body became dense and revealed the higher strength was that those hydrates were formed inside of the pore and filled in it and the unhydrated materials played the role of an inner-filler.

• Journal of the Korean Ceramic Society
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• v.43 no.10 s.293
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• pp.626-634
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• 2006

Ceramics manufacturers in the nation produced more than 5000 tons of ceramics wastes a year increasing industrial waste quantity: However, almost no researches were made to reduce environmental pollution and to recycle waste ware. In this study, white ware scraps that were produced at Icheon, Gyeonggi-do were recycled to make use of them as raw materials of ceramics body and to develop new ceramics body that had economic advantages and good quality. The findings showed that the addition of waste ware had limit of 20 wt% considering molding. The addition of waste ware of 20 wt% to white ware lowered baking temperature of the white ware that was added by waste ware of 20 wt% by 30$^{\circ}C$ than existing white ware, and property values were good, for instance, porosity of 3% in average and water absorptivity of 2% in average, and the bending strength recorded more than 800 kgf/$cm^2$ to be high than that of existing white ware being sold in market. The waste ware could be used to produce new ware body and to recycle resources and to solve environmental problems caused by burial and to improve property of ceramics and to save transportation costs as well as baking costs.

• Journal of the Korean Ceramic Society
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• v.31 no.12
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• pp.1467-1474
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• 1994

The effects of the dispersion, drying, and binder burning-out on the green-microstructures of gelcasted alumina were studied. The slip consisting of 55 vol% alumina powder and 5 wt% organic materials was well-dispersed by adding 0.28 wt% polyelectrolyte polymer. Green bodies were dried at >85% relative humidity at room temperature. Green-microstructures were observed to be depended on the heating rate during binder burnout. Constant drying rate was not observed in drying process of gelcasted alumina. Sintered body showed its relative density higher than 99% when it was sintered at 1$600^{\circ}C$ for 2 hours.

• Journal of Life Science
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• v.19 no.8
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• pp.1093-1103
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• 2009

The purpose of this study was to analyze the effects of ballet program training at the Royal Academy of dance (RAD) on body composition (BC), physical fitness (PF) and bone mineral density (BMD) in college women. The subjects for this study were 14 females aged 19 to 22, who were divided into the Experimental group (n=7, EG) and the Control group (n=7, CG). The RAD ballet program training was done by 7 subjects (EG), 60 minutes per day, three times a week for 12 weeks. The TBF and %fat significantly decreased and LBM increased in the Experimental group, but all the variables of Body composition in the Control group did not significantly changed. The AMS, Sit ups, STF, SLJ CFB and 1,200 m R & W in the EG significantly increased, but 1,200 m R & W in the CG decreased. The lumbar vertebra (LV), femoral neck (FN), greater trochanter (GT) and ward's triangle (WT) did not significantly change in the EG, but LV, GT and WT in the CG decreased. There was no significant difference in osteopenia for EG, but there were increases in GT and WT for the CG. There was significant correlation between BMDs and body weight, TBF, LBM, %fat, BMI, AMS. There was significant correlation between LV and FN and LV and whole body. In conclusion, regular and continuous RAD training was effective in improving the body composition, physical fitness and bone mineral density. Consequently, RAD training will be effective for preventing osteopenia and osteoporosis, and for improving the health-related fitness for college and middle-aged women.

• Journal of Ginseng Research
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• v.30 no.3
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• pp.100-105
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• 2006

Liver and kidney are specific organs which play an active role in biotransformation and detoxification mechanisms. Ant adverse effect of chemicals or heavy metal can cause the delay or fade in these mechanisms. Present study was designed to find out the protective effect of Panax ginseng extract on renal functions altered by mercuric chloride (heavy metal) in albino rat. Fifty albino rats were divided into 10 groups. Five groups for acute study and five groups for sud-acute study viz. control group (Tween 20 and distilled water), mercuric chloride treated group (0.926 mg/kg body wt. for acute and 0.044 mg/kg body wt. for sub-acute group after calculated $LD_{50}$ (9.26 mg/kg body wt.) by probit analysis (Finney, 1971), Panax ginseng extract treated group (10 mg/kg body wt. for acute and sub-acute sets), mercuric chloride treated followed by Panax ginseng extract and Panax ginseng extract followed by mercuric chloride group. All doses were given orally by gavage tube. The result revealed that the serum urea and creatinine significantly increased in mercuric chloride treated group, while significantly decreased (p<0.01) in Panax ginseng extract group after acute and sub-acute treatment. The biochemical estimation is also confirmed by nephropathological aspect. However, the Panax ginseng extract treated followed by mercuric chloride group is more prominent than the mercuric chloride treated followed by Panax ginseng extract group. It can be concluded that Panax ginseng extract had a protective nature on renal functions against mercuric chloride toxicity in albino rats.

• Journal of Animal Science and Technology
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• v.61 no.5
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• pp.285-293
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• 2019

The objective of this study was to verify the best mating age of gilts at the first parity. Gilts (n = 86) were divided into nine groups in a factorial arrangement with three Ages (AG1, ${\leq}220d$; AG2, 220 to 240 d; AG3, $240{\leq}d$), and three weights (WT1 ${\leq}140kg$; WT2, 140 to 149 kg; WT3, $150{\leq}kg$). A higher body weight gain in AG2 sows during gestation. Sows in AG2 group showed a higher body weight gain at first parity and backfat gain in the parity 2 and 3 during gestation. A greater insulin-like growth factor-1 (IGF-1) was observed in AG1 sows compared with AG3 sows at weaning in the second parity. Sows in WT1 group showed a significant positive effect on the plasma IGF-1 at breeding and weaning time in parity 2. Sows in AG3 group showed a higher plasma leptin at breeding, farrowing, and weaning in the parity 1, and at farrowing in parity 2. Sows in WT3 group showed a higher plasma leptin at breeding, farrowing, and weaning in the parities 1 and 2. Considering the insignificant longevity results, the most efficient time for gilts insemination can be at 220 d when their body weight is 140 kg or lower.

• Korean Journal of Materials Research
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• v.15 no.10
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• pp.652-656
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• 2005

The samples were prepared with hydroxyapatite(HAp) powder and Polycaboxylate (P.C/HAp=10, 15, 20, 25, 30, 35 $wt\%$). The hydroxyapatite green body with Polycaboxylate were obtained by compaction and drying at room temperature for 3hrs. The higher mechanical properties were observed in HAp sample with $35 wt\%$ Polycaboxylate. The average compressive ana bending strength in HAp with $35 wt\%$ Polycaboxylate are $302 kgf/cm^2$ and $213 kgf/cm^2$ respectively. This strength is higher compare to that of the cortical bone.

• Journal of the Korean Ceramic Society
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• v.19 no.2
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• pp.95-100
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• 1982

Instead of barium carbonate, domestic barite was used as the flux in manufacturing theinsulating porcelain. To avoid the problems arising from the decomposition of barite in the body during firing, BaO.$Al_2O_3$ was synthesized at $1300^{\circ}C$ for 5 hours. synthetic BaO.$Al_2O_3$ was mixed with other materials such as kaoline, alumina, clay, dolomite. The RO content (CaO. MgO. BaO) of the batches was varied from range of 4 to 14wt. % at 2wt. % - intervals, and firing temperature was varied from 1280 to 140$0^{\circ}C$-at 4$0^{\circ}C$ intervals The properties such as water absorption, bulk density. mechnical strength, specific resistance, and linear shrinkage were measured. The body containing 12 wt.% of RO content showed the satisfactory for the application in the Fixed Carbon Film Resistor.

• Journal of Life Science
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• v.20 no.1
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• pp.124-132
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• 2010

Among students of 'K' boarding high school, located in 'B' city, 32 students whose % body fat was 30% or above were divided into three groups - two exercise groups and one control group. They performed Combined Training - a mix of weight training (WT) and step box training (SBT) - for 65 min a day, 3 days a week, for 8 weeks in total. Group A performed WT 70-80%$RM{\times}3$ sets+SBT (RPE 11-13)${\times}1$ set, and group B performed WT 70-80%$RM{\times}1$ set+SBT (RPE 11-13)${\times}3$ sets to yield data on changes of body composition (Soft Lean Mass, SLM), %fat, WHR), HbA1c, and HOMA-IR. Paired t-test was used to process data within each group. Pre- and post experiment differences rates (%diff) were used to perform one-way ANOVA (Duncan test) for group comparisons. The conclusions derived are as follows. Regarding body composition, exercise groups showed an increase in SLM, but there was no such change in the control group. WHR decreased in group A, but increased in the control group. The % body fat decreased in both exercise groups, but increased in the control group. As for the group comparisons, SLM in group A showed a greater increase than in group B and the control group. WHR in groups A and B showed a greater decrease than the control group. The % body fat in groups A and B showed a greater decrease than the control group. The exercise groups showed a significant decrease in HOMA-IR, but the control group showed a significant increase in HOMA-IR. As for the group comparisons, groups A and B showed a greater decrease in HOMA-IR than the control group. The exercise groups showed a significant decrease in HbA1c, however, the control group showed no change in HbA1c. As for the group comparisons, group A showed a greater decrease in HbA1c than the control group. These results confirm that combined training is more effective in improving body composition and metabolic factors when it includes a high proportion of resistance training, rather than aerobic exercise. The results of the study suggest that it is advisable to set a high proportion of WT when deciding the intensity of combined training.

• Korean Journal of Materials Research
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• v.14 no.6
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• pp.375-378
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• 2004

The samples were prepared with hydroxyapatite(HAp) powder and eugenol (Eugenol/HAp = 15, 20, 25, 30wt%). The samples were dried at room temperature. The higher mechanical properties was observed in HAp sample with 25wt% Eugenol. The average compressive and bending strength in HAp with 25wt% Eugenol are 542 kgf/$\textrm{mm}^2$ and 366 kgf/$\textrm{mm}^2$ respectively. This strength is higher compare to that of the cortical bone.