• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.6
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• pp.199-208
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• 2021

The extrudability of 3D printed concrete and its member strength can be highly influenced by water cement ratio (W/C) and printing time gap (PTG). In this study, mold cast specimens and 3D printed specimens were fabricated with variables of W/C ratio and PTG, and their shear bond strength and interlayer surface moisture content were measured and analyzed. The test results showed that the shear bond strength is greatly influenced by the amount of interlayer surface moisture. It is thus recommended that proper amount of interlayer surface moisture with respect to PTG needs to be maintained to have a required interlayer shear bond strength. In addition, further research is required to estimate the effect of many environmental factors that can influence the interlayer surface moisture content.

• Preventive Nutrition and Food Science
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• v.17 no.3
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• pp.203-209
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• 2012

The effects of variable moisture content, screw speed and barrel temperature on the physicochemical properties of red ginseng powder extrudates were investigated. The raw red ginseng powders were processed in a co-rotating intermeshing twin-screw extruder. Primary extrusion variables were feed moisture content (20 and 30%), screw speed (200 and 250 rpm) and barrel temperature (115 and $130^{\circ}C$). Extruded red ginseng showed higher crude saponin contents (6.72~7.18%) than raw red ginseng (5.50%). Tested extrusion conditions did not significantly affect the crude saponin content of extrudates. Increased feed moisture content resulted in increased bulk density, specific length, water absorption index (WAI), breaking strength, elastic modulus and crude protein content and decreased water solubility index (WSI) and expansion (p<0.05). Increased barrel temperature resulted in increased total sugar content, but decreased reducing sugar content in the extrudate (p<0.05). Furthermore, increased barrel temperature resulted in increased amino acid content and specific length and decreased expansion and bulk density of extrudates only at a higher feed moisture content. The physicochemical properties of extrudates were mainly dependent on the feed moisture content and barrel temperature, whereas the screw speed showed a lesser effect. These results will be used to help define optimized process conditions for controlling and predicting qualities and characteristics of extruded red ginseng.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.196-200
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• 2011

'Superjami', a new blackish purple pigmented rice cultivar was derived from a cross between 'CG2-3-5-1-6-1' (developed from a cross between 'Heugjinjubyeo' and 'Suweon 425') as high amount of C3G (Cyanidin 3-glucoside) and 'Daeribbyeo 1' with large seed size in 2003, and selected by pedigree breeding method until $F_7$ generation. As a result, a promising line, 'SR28721-7-9-3-1-2-1', was developed and designated as the name of 'KNOU 5' in 2008. This variety has about 125 days to heading after sowing and has 74.9 cm culm height. The ratio of fertility of 'Superjami' was about 89.6% and 1,000-grain weight was about 26.2 g. It was 1.5 times heavier than 'Heugjinjubyeo'. 'Superjami' has 10 times higher C3G content compared with 'Heugjinjubyeo'. The yield potential of 'Superjami' in brown rice was about 6.3 MT/ha at ordinary fertilizer level in local adaptability test.

• Food Science and Preservation
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• v.18 no.5
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• pp.779-785
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• 2011

This study was conducted to investigate and compare the characteristics of alcohol fermentation in oriental melon by different yeast. As a result, no significant difference in pH, total acidity and sugar content was found in alcohol fermentation of oriental melon by different yeast. The pH was shown to be constantly maintained but the total acidity was shown to increase during fermentation process. The sugar content was rapidly decrease starting from 3 day of fermentation, and it was reduced to be approximately 7 oBrix after fermentation. For organic acid content, lactic and citric acid contents were shown to be the highest in all periods of fermentation, which revealed that lactic and citric acid were major organic acids. Free sugar content were shown to gradually decrease during the fermentation and to be rarely detected at 9 days of fermentation. Alcohol content was shown to be 14.20% at (C) S. cerevisiae RC-212, which was the highest content. It was shown to be more than 12% at other periods, which showed that no significant difference in alcohol content was found according to different yeast. For alcohol components, acetaldehyde content was shown to be the highest at (E) S. cerevisiae K1-V1116, and methanol content was shown to be relatively higher at (C) S. cerevisiae RC-212 and (D) S. bayanus EC-1118. N-propanol, 2-methyl-1-propanol and isoamyl alcohol, which belong to fusel oil, were shown to be produced at 3 day of fermentation and gradually increase. These results, no significant difference in physicochemical properties of alcohol fermentation in oriental melon by different yeast.

• Journal of Nutrition and Health
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• v.28 no.1
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• pp.5-14
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• 1995

The present study was performed to investigate the effect of cereal fiber on lipid concentration of liver and serum in rats. Male Sprague-Dawley rats weighing 180$\pm$4g were divided into five groups by completely randomized block design : R, BR, B, W, and F. Each group fed a diet containing 0.7% cholesterol and a kind of cereal among rice(R), brown rice(BR), barley(B), whole wheat(W), and wheat flour(F) for 5 weeks. The results were summarized as follow : 1) Food intake. weight gain and feed efficiency ratio were not significantly different among the groups. 2) Fecal wet weight and dry weight were significantly higher in W group which fed the most amount of IDF(insoluble dietary fiber). 3) The weight of large intestine was significantly heavier in the W group compared to the others. But the weights of liver, stomach and small intestine were not significantly different among the groups. 4) Total lipid. triglyceride(TG) and total cholesterol(TC) content in liver were significantly different among the groups. The values were the lowest in the B group whose intake of SDF(soluble dietary fiber) was the highest 5) TC content in serum was not significantly different among the groups. TG content in serum was significantly lower in the rest groups than in the R group. HDL-c and free-c content in serum were significantly higher in the B group than in the rest groups. HDL-c/LDL-c, free-c/ester-c ratio were the highest in the B group but not significant. Above results show that the dietary fiber contained in cereals has physiological effects and they are different depending on fractions, IDF and SDF.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.401-407
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• 2008

This study was carried out to investigate the effect of feeding periods of dietary Rhus verniciflua Stokes (RVS) on the quality characteristics of Hanwoo beef during refrigerated storage. Hanwoo steers were fed a 4% RVS-contained diet for 0 (control), 3, 4, 5, or 6 mon prior to slaughter (28 mon of age). The M. semitendino년 from carcasses were stored at $3{\pm}0.2^{\circ}C$ for 7 d. The crude fat content was lower in the 4 and 5 mon groups than in the other groups (p<0.05), however the crude protein content and water-holding capacity (WHC) were higher in the 4 and 5 mon groups than in the other groups (p<0.05). The monounsaturated fatty acid (MUFA) content was higher in the 3, 4, and 5 mon groups than in the other groups (p<0.05). During storage. the TBARS content was reduced in the RVS groups, and the MetMb content showed slower accumulation in the 3, 4, and 5 mon groups than in the other groups. With regard to meat color, the 3, 4, and 5 mon groups had higher L, a, and C values than the other groups until 7 d, and in particular, the a value at 7 d was the highest in the 4 mon group (p<0.05). Consequently, the beef from 4% RVS-fed Hanwoo for 4-5 mon was effective at improving the WHC, MUFA content, and color stability relative to the other beef.

• Korean Journal of Metals and Materials
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• v.47 no.4
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• pp.217-222
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• 2009

Cu as a tramp element has been reported to encourage transverse cracking upon straightening operation during continuous casting or mini-mill processing. Therefore, the hot workability of steels containing Cu should be investigated. The purpose of the present study was to examine the effect of Cu contents on the hot ductility of low carbon steels by using hot compression test. Hot compression test was carried out using a Gleeble. The specimens were heated to $1300^{\circ}C$ for solution treatment and then held for 300s before cooling at a rate of $1^{\circ}C/s$ to test temperatures in the range of $650{\sim}1150^{\circ}C$ ($50^{\circ}C$ intervals) with strain rate of $5{\times}10^{-3}/s$. In Cu containing steels, the hot ductility was decreased with increasing Cu content at high temperature region which is to be attributed to copper enriched phase formed at scale/steel interface, and low hot ductility with increasing Cu content at low temperature region is attributable to the strengthening of matrix by the formation of ${\varepsilon}-Cu$. The width of ductility trough region was decreased with increasing Cu content.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.79-79
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• 2001

This study was conducted to measure the total protein, DNA, and RNA contents of corpus luteum(CL) in various stages of estrous cycle and pregnancy. CLs were collected from a local slaughterhouse and stages of the estrous cycle of CL were classified as CL1~2, days 1 to 10; CL3(with/without central cavity), days 11 to 17; CL4, days 18 to 20 by method of Ireland et. al(1980) and stages of the pregnancy of CL were classified as P1~3, months 11~3: P4~6, months 4~6; P7~9, months 7~9 of pregnancy. CL3 with/without central cavity(CC) was identified as described by Kastelic et. al.(1990)-CL with CC, more than 2mm in diameter; CL without CC, less than 2mm in diameter. In total protein content, CL3 with CC was significantly lower than P7~9(p<.05). The total DNA content was lower in CL3 with CC than CL3 without CC and CL4(p<.05). In protein : DNA ratio, CL3 with CC was significantly lower than CL4(p<.05), CL3 without CC was significantly lower than P7~9(p<.05), CL4 was significantly lower than CL3 with CC, P1~3 and P7~9(p<.05). No differences were observed in RNA content, protein:RNA ratio, RNA/DNA of CLs in stages of estrous cycle and pregnancy.

• Journal of the Korean Society of Food Culture
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• v.28 no.3
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• pp.320-327
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• 2013

The quality characteristics of Omija (Schizandra chinesis Baillon) extracts under various extraction temperatures and times were examined. The pH level of the extracts ranged from 3.35-3.47. The sugar and solid content of the samples significantly increased with increasing extraction temperatures and times (p<0.01). In contrast, the lightness of the extracts decreased with increasing extraction temperatures and times (p<0.001). In a palatability test, extracts boiled at $80^{\circ}C$ for 30 minutes scored high in terms of color, flavor, turbidity, sourness, and overall acceptability. Hydroxy radical scavenging activity and polyphenol content of the extracts significantly increased with increasing extraction temperatures and times (p<0.01). Furthermore, direct correlations between hydroxy radical scavenging activity and polyphenol content (or flavonoid content) were established through simple regression (r>0.9) for different extraction temperatures and times. From these results, extracts boiled at $80^{\circ}C$ for 120 minutes is the best to product omija beverage considering functionality and sensory evaluation as well.

• Food Engineering Progress
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• v.21 no.4
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• pp.351-359
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• 2017

This study investigates the quality characteristics of dough and bread added with 6% chestnut shell powder and extruded chestnut shell powder at various conditions. As extrusion process variables, melt temperature ($110^{\circ}C$, $130^{\circ}C$, $150^{\circ}C$) and moisture (25% and 30%) were controlled. Total dietary fiber content was slightly increased in extruded chestnut shell powder group. In the farinogram, absorption was significantly increased in the group of 25% moisture content and 30% moisture content (p<0.05). After 2 hours and 3 hours, the leavening heights of dough for control showed a similar tendency to that of dough with extruded chestnut shell at a melt temperature $150^{\circ}C$ and with moisture content of 25% and 30%. Specific volume was the highest at a control of $3.74{\pm}0.08cc/g$ and extruded chestnut shell powder group was slightly higher than the chestnut shell powder group. Firmness after 1 day on control of $107.42{\pm}14.52g$ was similar to that of the bread with extruded chestnut shell at a temperature of $150^{\circ}C$ and moisture content of 25% for $113.33{\pm}6.17g$. In conclusion, the extrusion-cooking of chestnut shell powder improved the quality characteristics of dough and bread. The optimum combinations of conditions in tested range were melt temperature at $150^{\circ}C$ and moisture content at 25%, and melt temperature at $130^{\circ}C$ and moisture content at 30%.