• Food Science and Preservation
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• v.8 no.1
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• pp.66-73
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• 2001

This study was carried out to know whether $\beta$-galactosidase is directly important or not on fruit softening during the development of peach fruits compared to those in the stage stage. It was investigated that the flesh firmness, cell wall components, and the glycosidase activities of the peach fruits with a fast softening cultivar, 'Mibeakdo', a slow softening cultivar,'Yumyung'and a middle softening cultivar, 'Okubo$\beta$, at different developmental stages, on 13 May, 16 June, 16 July, and 5 August and on 28 August which harvested only 'Yumyung' fruits. In order to investigate the amounts of total sugar and non-cellulosic neutral sugar, the cell wall materials of each fruit were solubilized in distilled water, 0.05M CDTA, 0.05M Na$_2$CO$_3$, 4% KOH, and 24% KOH sequentially. During the fruit development, the fruit firmness of three cultivars decreased and the fruit firmness of 'Yumyung' was higher than that fo 'Mibeakdo' and 'Okubo' in the overall period. During the fruit development, the changes of total sugar amounts of each measured fractions were similar among peach cultivars. Arabinose and galactose were the predominant non-cellulosic neutral sugars in all the fractions including cell wall material of the three cultivars. There was an active relationship between the changes of flesh firmness in three cultivars and the mol % changes of rhamnose on 5 August which was the harvest date of 'Mibeakdo' and 'Okubo' fruits. The activity of soluble $\beta$-galactosidase was high at the early developmental stage and then dropped to a very low activity level in all cultivars. The activity of cell wall-bound $\beta$-galactosidase was high at the early developmental stage and then decreased continuously through the harvest date. In addition the changes of other glycosidase activities were similar among cultivars.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.940-947
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• 2017

Goat milk has a protein composition similar to that of breast milk and contains abundant nutrients, but its use in functional foods is rather limited in comparison to milk from other sources. The aim of this study was to prepare a goat A2 ${\beta}$-casein fraction with improved digestibility and hypoallergenic properties. We investigated the optimal conditions for the separation of A2 ${\beta}$-casein fraction from goat milk by pH adjustment to pH 4.4 and treating the casein suspension with calcium chloride (0.05 M for 1 h at $25^{\circ}C$). Selective reduction of ${\beta}$- lactoglobulin and ${\alpha}_s$-casein was confirmed using sodium dodecyl sulphate-polyacrylamide gel electrophoresis and reverse-phase high-performance liquid chromatography. The hypoallergenic property of A2 ${\beta}$-casein fraction was examined by measuring the release of histamine and tumor necrosis factor alpha from HMC-1 human mast cells exposed to different proteins, including A2 ${\beta}$-casein fraction. There was no significant difference in levels of both indicators between A2 ${\beta}$-casein treatment and the control (no protein treatment). The A2 ${\beta}$-casein fraction is abundant in essential amino acids, especially, branched-chain amino acids (leucine, valine, and isoleucine). The physicochemical properties of A2 ${\beta}$-casein fraction, including protein solubility and viscosity, are similar to those of bovine whole casein which is widely used as a protein source in various foods. Therefore, the goat A2 ${\beta}$-casein fraction may be useful as a food material with good digestibility and hypoallergenic properties for infants, the elderly, and people with metabolic disorders.

• Composites Research
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• v.28 no.5
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• pp.316-321
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• 2015

This study investigated the effects of microcapsules on mechanical properties and thermal stability of the composite material containing self-healing microcapsules. To this end, tensile specimens and flexural specimens containing melamine-urea-formaldehyde (M-U-F) shell walled microcapsules with diameters of $70{\sim}130{\mu}m$ were manufactured. Varying amount of microcapsules in the specimens was considered: 0 wt%, 0.5 wt%, and 1.0 wt%. The tensile and flexural tests were conducted to evaluate mechanical properties of the specimens containing the microcapsules and the thermogravimetric analysis test was performed to evaluate the thermal stability of the specimens containing the microcapsules. The results show that the tensile strength of the specimens was sensitive to the amount of the microcapsules compared to the tensile modulus even though the tensile modulus of the specimens was not significantly affected by the amount of the microcapsules. However, reduction of the tensile strength was not linearly proportional to the amount of microcapsules; similar results were observed in the flexural test. The weight changes of the specimens containing the microcapsules, as a function of temperature, were similar to those specimens without microcapsules. The thermal stability of the specimens was not affected significantly by the microcapsules embedded in the specimens.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1117-1123
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• 2016

Roller-Compacted Concrete Pavement (RCCP) is a type of pavement that shares conventional concrete pavement material characteristics and asphalt pavement construction characteristics. Even though RCCP is compacted in the same way and have similar aggregate gradation to asphalt pavements, its materials and structural performance properties are similar to those of conventional concrete pavement. With cement hydration and aggregate interlock, Roller-Compacted Concrete or RCC can provide strength properties equal to those of conventional concrete with low cement content. Therefore, compaction ratio of RCC can highly influence on its strength. In general, 95% of compaction ratio is required for proper strength development. RCC strength can be highly influenced by compaction energy which depends on compaction equipment and compaction method. Therefore, it is necessary to analyze the relationship between compressive strength and compaction ratio of RCC. RCCP specimens were produced at different compaction ratio by using different compaction methods and energies. The compaction ratio was defined by the ratio of the specimen's dry density and its maximum dry density. The maximum dry density was obtained from Modified Proctor test. 28 days compressive strength corresponding to each compaction ratio case was tested. Finally, the relationship between compressive strength and compaction ratio can be analyzed. For application of roller-compacted concrete in domestic construction site, the relationship is important for field compaction management.

• Cartoon and Animation Studies
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• s.48
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• pp.141-172
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• 2017

The film (2000) and (2016) are based on different time slips from each other. However, these two films have many common elements that make one illusion-based illusion. In the common elements, the main characters (being and thing) are traversed at different times and directed as a cyclical one. Also, among these, the movement link of the time and space has a commonality that it becomes possible through a medium ( - radio, you, there - pill). As a result, a series of scenes expressed in showed that the scene of produced in 2000 was greatly circulated. The reason why two movies have similar structure is that the basic framework of video media based on time slip is similar. Therefore, the purpose of this study is not to analyze the problem of quoting and borrowing of two films as mentioned in the paper. To add up, the material of video media is manifold which is a dynamic object of potential which is unlimited and opened, and by rearranging one media it can be created by escaping from one territory. Also, it is a study of analysis to contribute to producer or researcher as a time slip video creation reference connecting times based on the manifold arrangement from two films.

• Journal of Conservation Science
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• v.33 no.4
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• pp.225-239
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• 2017

This study aimed to investigate the chemical properties and production techniques for white wares from the Gwirae-1ri 3rd, Songok-3ri 2nd kiln sites in Kangwon Wonju regions. Further, another aim was to determine the correlation among the materials used to produce the white wares. The analysis of white wares in Kangwon Wonju regions produced the following results. The excavated white wares were analyzed using the Seger formula, and all the samples showed similar clay sources ($RO_2:4.33-5.82$, $RO+R_2O:0.32-0.43$) and glaze sources. Moreover, the white wares were made of host rocks of the same geological origin, according to the results of the rare earth elements analysis. When the crystalline phases of the white wares were investigated via the XRD analysis, quartz and mullite were found in all the samples, and their proportions were similar to each other. Although the firing temperatures for the samples were different, most were fired at a temperature below $1,200^{\circ}C$, with some being fired at temperatures as low as $1,000{\pm}20^{\circ}C$.

• Tunnel and Underground Space
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• v.14 no.1
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• pp.54-68
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• 2004

In this study, scaled model tests were performed on blasting demolition of reinforced concrete structures and the experimental results were analyzed in comparison with the results of numerical analysis. The tests were designed to induce a progressive collapse, and physical properties of the scaled model were determined using scale factors obtained ken dimension analysis. The scaled model structure was made of a mixture of plaster, sand and water at the ratio determined to yield the best scaled-down strength. Lead wire was used as a substitute for reinforcing bars. The scaled length was at the ratio of 1/10. Selecting the material and scaled factors was aimed at obtaining appropriately scaled-down strength. PFC2D (Particle Flow Code 2-Dimension) employing DEM (Distinct Element Method) was used for the numerical analysis. Blasting demolition of scaled 3-D plain concrete laymen structure was filmed and compared to results of numerical simulation. Despite the limits of 2-D simulation the resulting demolition behaviors were similar to each other. Based on the above experimental results in combination with bending test results of RC beam, numerical analysis was carried out to determine the blasting sequence and delay times. Scaled model test of RC structure resulted in remarkably similar collapse with the numerical results up to 900㎳ (mili-second).

• Journal of Korean Society on Water Environment
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• v.20 no.4
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• pp.313-320
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• 2004

In this study, variable characteristics of drinking water and the influences on underground water reservoirs, rooftop water tanks, and service water pipes in the building were assessed. The influence of underground water reservoir material and water capacity on water quality also were assessed. The results are the following as; First of all, the drinking water passing through underground water reservoirs or service water pipes in the building, averagely metal component concentration more increased from percent of 41.3 to percent of 74.2 totally than other items of water quality. On the other hand, both residual chlorine and total solid highly decreased 65.6 percent and 35.3 percent, respectively. Therefore, it was thought that water quality could be getting worse for microorganism re-growth by residual chlorine reduction, and total solid also could be a cause for extraneous matters accumulated in water reservoir. Secondly, the variations on water quality of each stage for water supply system in the building were higher in water service pipes connected from rooftop water tanks to the tap than in underground water reservoirs. In addition to, among of twelve items on water quality, ten items on water quality except dissolved oxygen and residual chlorine increased. Therefore, it was thought that the influence of water service pipes connected from rooftop water tanks to the tap on water quality were higher than other stages of water supply system in the building. Thirdly, in case of materials of underground water reservoir, it was likely that the variation on water quality by stainless steel and concrete materials got some similar. In case of water capacity, the variations on water quality of underground water reservoirs over $1,000m^3$ higher than those under $1,000m^3$. That reasons was likely that the retention time(49.72 hours averagely) of underground water reservoirs over $1,000m^3$ was two times longer than it of those under $1,000m^3$(23.37 hours). Therefore, it was thought that the influence on water quality by materials were some similar, but in case of water capacity, the influence of underground water reservoirs were higher.

• Korean Journal of Medicinal Crop Science
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• v.12 no.1
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• pp.79-84
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• 2004

To develop a new functional materials, angiotensin converting enzyme (ACE) inhibitory activity, antioxidant effect and total phenolic content of Hovenia dulcis Thunb. cortex were evaluated. Methanol and water extract of H. dulcis inhibited ACE by 81% and 76%, respectively, at the concentration of $4,000\;{\mu}g\;m{\ell}^{-1}$ which were similar level with that (85%) of commercial peptide-type ACE inhibitor. Superoxide radical scavenging activity of two extracts $(99.5%{\sim}99.9%)$ were stronger than that (69%) of ascorbic acid at the final concentration of $200\;{\mu}g\;m{\ell}^{-1}$. Among the solvent fractions, ether and ethylacetate fraction showed also potent scavenging activities (91% and 85%) for superoxide radical. Inhibitory activities of two extracts on oxidation of human low density lipoprotein (LDL) which were similar with that of ${\alpha}-tocopherol$, were higher than 80% at the concentration of $50\;{\mu}g\;m{\ell}^{-1}$. Total phenol contents of methanol and water extracts were 7.2% and 3.6%, respectively, and that of ethylacetate showed the highest value as 60.8% among the solvent fractions. Therefore, it has been suggested that H. dulcis cortex could be a effective anti-hypertention and antioxidant resource to develope a new functional material.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.160-169
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• 2008

Bakcground: To treat anastomosis site stenosis and occlusion of the artificial vessels used in vascular surgery, tissue-engineered artificial vessels using autologous cells have been constructed. We developed artificial vessels using a polymer scaffold and autologous bone marrow cells and performed an in vivo evaluation. Material and Method: We manufactured a vascular scaffold using biodegradable PLCL (poly lactide-co-${\varepsilon}$-caprolactone) and PGA (poly glycolic acid) fibers. Then we seeded autologous bone marrow cells onto the scaffold. After implantation of the artificial vessel into the abdominal aorta, we performed an angiography 3 weeks after surgery. After the dogs were euthanized we retrieved the artificial vessels and performed histological analysis. Result: Among the six dogs, 2 dogs died of massive bleeding due to a crack in the vascular scaffold 10 days after the operation. The remaining four dogs lived for 3 weeks after the operation. In these dogs. the angiography revealed no stenosis or occlusion at 3 weeks after the operation. Gross examination revealed small thrombi on the inner surface of the vessels and the histological analysis showed three layers of vessel structure similar to the native vessel. Immunohistochemical analysis demonstrated regeneration of the endothelial and smooth muscle cell layers. Conclusion: A tissue engineered vascular graft was manufactured using a polymer scaffold and autologous bone marrow cells that had a structure similar to that of the native artery. Further research is needed to determine how to accommodate the aortic pressure.