• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.825-828
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• 1998

The X-ray spectra dependence for intensifying screens of medical radiography was investigated through analysis of the absorbed coefficiency($\mu$), absorbed efficiency(${\eta}_{\alpha}$) and absorbed ratio(R). It was found that the absorbed coefficiency was increased in the order of $CaWO_4$$CaWO_4$ screen showed the highest value.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.106-109
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• 2005

The $(Sr_{1-x}Ca_x)TiO_3$(SCT) thin films are deposited on Pt-coated electrode (Pt/TiN/$SiO_2$/Si) using RF sputtering method with substitutional contents of Ca. The optimum conditions of RF power and Ar/$O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin film was about 18.75[$\AA$/min]. The dielectric constant was increased with increasing the substitutional contents of Ca, while it was decreased if the substitutional contents of Ca exceeded over 15[mol%]. The capacitance characteristics had a stable value within ${\pm}4$[%] in temperature ranges of -80~+90[$^{\circ}C$].

• The Korean Journal of Community Living Science
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• v.14 no.2
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• pp.63-70
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• 2003

In this experiment, the curd was made from soybean and cow's milk in the ratio of 7 to 3, and coagulated with Glucono-delta-lacton(GDL) and $CaSO_4&.$2H_{2}O& in the 1:1 ratio. During the procedure, the mulberry leaf powder was added. The amount of the added powder varied from 0.1 % to 0.5 %. This experiment aimed to show the change of yield, general components, minerals, amino acid, changes of pH, sensory properties of these products. As mulberry leaf powder addition increased, crude protein, crude fat, crude ash content, minerals and amino acids increased. Whereas moisture content decreased, and in particular,$Ca^{++}$, $K^+$ and $Na^+$ increased. On the other hand, in the sensory properties, the levels of satisfaction about the color, appearance, flavor, texture and savory were lower in mulberry leaf powder added than under control.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1189-1195
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• 2018

This study developed an antimicrobial hydrogel to control Listeria monocytogenes in Yukhoe (Korean beef tartare). Four hydrogels (hydrogel 1: 5% alginate+1% chitosan+0.2% $CaCl_2$, hydrogel 2: 1% ${\kappa}$-carrageenan+1% chitosan, hydrogel 3: 2% ${\kappa}$-carrageenan+1% $CaCl_2$, and hydrogel 4: 2% ${\kappa}$-carrageenan+3% $CaCl_2$) were prepared. The hydrogels then absorbed 0.1% grapefruit seed extract (GSE) and 0.1% citrus extract (CE) for 30, 60, 120, and 240 min to be antimicrobial hydrogels. To select the most effective antimicrobial hydrogel, their swelling ratio (SR) and antilisterial activities were determined. The selected hydrogel ($2{\times}2cm$) was then placed on surface of beef (round; $3{\times}3cm$), where L. monocytogenes (ca. $10^6CFU/g$) were inoculated, and the cell counts were enumerated on PALCAM agar. Among the hydrogels, the SR of hydrogel 1 increased with absorbing time, but other hydrogels showed no significant changes. Antimicrobial hydrogel 1 showed higher (p<0.05) antilisterial activity than other antimicrobial hydrogels, especially for the one absorbed the antimicrobial for 120 min. Thus, the antimicrobial hydrogel 1 absorbed antimicrobials for 120 min was applied on raw beef at $4^{\circ}C$, and reduced (p<0.05) more than 90% of L. monocytogenes on raw beef. These results indicate that antimicrobial hydrogel 1 formulated with 0.1% GSE or 0.1% CE is appropriate to improve the safety of Yukhoe by reducing psychrotrophic L. monocytogenes cell counts on raw beef.

• Korean Journal of Veterinary Research
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• v.40 no.4
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• pp.755-762
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• 2000

The aim of this investigation was to examine the effects of osteocalcin, bone-specific alkaline phophatase, estrogen, insulin-like growth factor-I (IGF-I), Ca, P and bone mineral density on osteoporosis induced by ovariectomy in rats. Female Sprague-Dawley 30 rats of three-forth's birth, weighing $215{\pm}10g$, were divided into two groups including the sham operation group(5 heads) and ovariectomy group(25 heads). They were fed normal diets for 2 weeks before the experimental operation and for 8 more weeks after operation. The level of osteocalcin, TALP, BALP, estrogen, bone mineral density and IGF-I were increased in experimental group, but a little increased in sham operation group at same period. The change of rates of osteocalcin, TALP, BALP, estrogen, bone mineral density and IGF-I were significantly higher in experimental group than sham operation group. $Ca^{2+}$ was not changed between two groups and P was significantly decreased in experimental group and Ca/P ratio was higher in experimental group than sham operation group. Body weights were increased in all two groups and growth rate per day was higher in experimental group than sham operation group. However, femur weight I body weight ratio was lower in experimental group than sham operation group.

• Journal of Nutrition and Health
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• v.31 no.1
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• pp.36-45
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• 1998

Dietary and other factors affecting bone density of 32 Korean healthy college women aged 19-23 years were assessed. Data for food and nutrient intake was obtained by a semiquantitiative food frequency questionnaire. Serum samples were anlayzed for total Ca, P, Ca++, PTH, calcitonin and 25-hydroxycholecalciferol , (25-OH-Vit D3) and BMDs of lumbar spine(L2-L4), femoral neck(FN), ward's triangle (WT) and trochanter(TR) were measured by an XR-series X-ray bone densitometer. Relationships between the factors and BMDs were analyzed by stepwise multiple regression analysis and Pearson's correlation coefficient(r). The results are summarized as follows. Mean daily intake of energy(86.1%), Ca(74.3%), vitamin A (53.75), Fe(49.75) and vitamin B$_2$(86.6%) were lower while other notrients incuding P(126%) were higher than the Korean RDA. The BMDs of lumbar spines and femurs ranged from 0.73g/$\textrm{cm}^2$ to 1.23g/$\textrm{cm}^2$and 0.48g/$\textrm{cm}^2$ to 1.04g/$\textrm{cm}^2$, respectively. Both protein and P intakes were inversely associated with serum total Ca. Furthermore, Ca intake as well as Ca/P ratio (Ca/P) were inversely associated with serum ionized Ca(Ca++) concentration. The intakes of protein P and Ca , however, were not significantly associated with the BMDs measured in this study. There were little association between BMDs and alcoholic beverage or caffeine consumption. The only significant association detected was a positive relationship between caffeine consumption and BMD of WT. It seemed to be noticeable that BMDs of L2-L$_4$, FN and WT were significantly inversely associated with serum P concentration. However, there was no significant association between BMDs and the levels of total Ca to Ca++ in serum. Body weight was positively associated with BMD of lumbar spine and BMI was also positively associated with BMDs of FN and WT. The subjects who had an early menarche appeared to have higher BMDs than those who had had a late mearche. According to stepwise multiple regression analysis. Menarche and BMI were stronger determinants of BMDs in the young women than was diet. P intake appeared to be a more potent dietary determinant than Ca intake. The three factors, menarche, BMI , and P intake , additionally accounted for 24% and 378% of the variance in BMDs of FN and L$_2$-L$_4$, respectively. Further investigation is necessary to determine the factors needed to increase serum P level which negatively affects. BMD in young Korean college women.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.2
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• pp.3-9
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• 2005

In this study, the chip breaking characteristics of S, PbS and BiS free machining steels have been assessed. PbS free machining steel shows the lowest value of chip thickness ($t_c$) under the same cutting conditions. SM10C steel has the largest value of the chip cross-section area ratio ($R_{CA}$). As the feed rate becomes larger the chip breaking cycle time ($T_B$) decreases and the chip breaking index ($C_B$) increases. The properly controlled-C type chip has been obtained with the value of $C_B$ between 0.05 and 0.2. Free machining steel, PbS produces the properly controlled-C type chip in a wider feed rate range than other steels.

• Journal of the Korean Home Economics Association
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• v.24 no.3
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• pp.97-101
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• 1986

The content of sugar in human milk was almost twice as much as that in cow's milk. The content of ash in cow's milk was twice as much as that in human milk. Cow's milk had a greater proportion of sodium than human milk. the ratio of P/Ca in human milk was as much lower than that in cow's milk. Cow's milk had more Cu than human milk.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1630-1636
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• 2009

Nine alkali-activated (AA) mortars were mixed and cured at water or air-dried conditions to explore the significance and limitation for the application of the combination of Ba and Ca ions as an alkali-activator. Ground granulated blast-furnace slag (GGBS) was used for source materials, and calcium hydroxide (Ca(OH)₂) and barium hydroxide (Ba(OH)₂) were employed as alkali activators. Test results clearly showed that the water curing condition was more effective than the air-dried curing condition for the formation of the denser calcium silicate hydrate (C-S-H) gels that had a higher molar Si/Ca ratio, resulting in a higher strength development. At the same time, the introduction of Ba(OH)₂ led to the formation of 2CaO·Al₂O₃·SiO₂·8H₂O (C₂ASH₈) hydrates with higher molar Si/Al and Ca/Al ratios. Based on the test results, it can be concluded that the developed cementless mortars have highly effective performance and high potential as an eco-friendly sustainable building material.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.91.1-91.1
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• 2013

Since 2010, we have improved the Fast Imaging Solar Spectrograph (FISS) and observed the Sun. From the early observations we noticed two instrumental problems: poorer spatial resolution due to chromatic aberration and lower light level in the Ca II band. We tried to overcome these problems in two ways. First, we updated the relay optics. With the new one, we don't find any noticeable chromatic aberration between Ha and CaII and as a result can obtain the high resolution data in Ca II as well. Second, we replaced mirrors and the grating. This resulted in the increase of light level by a factor of up to 2.5, and hence in the high S/N ratio. The images constructed from the recentest observations indicate that the performance of the FISS is now much closer to our original intention than at the beginning.