• Korean Journal of Metals and Materials
• /
• v.46 no.11
• /
• pp.713-724
• /
• 2008

The need to lower the weights of automotive vehicle and to improve the safety of cars has resulted in the development of high strength steels such as TRIP(Transformation Induced Plasticity) and DP (Dual Phase) steel. It is well known that the higher strength of steel shows the poorer press formability. Among the high strength steels, DP steel shows several good characteristics such as low yield ratio, high initial n value, high elongation, high bake hardenability and anti-aging property. However, there's a certain limit in application of DP steels to the automotive panel parts because their poor deep drawbility caused by martensite. In this study, the effect of alloying elements on the deep drawability and recrystallization texture in TS 440MPa grade DP steel with 0.015~0.02% carbon has been investigated on the base of SEM, TEM, XRD and EBSD analysis.

• Computers and Concrete
• /
• v.33 no.2
• /
• pp.205-216
• /
• 2024

Self-Curing Self Compacting Concrete (SCSCC), is a special concrete in contemporary construction practice aimed at enhancing the performance of structural concrete. Its primary function is to ensure a sufficient moisture supply that facilitates hydration along with flow, particularly in the context of high-rise buildings and tall structures. This innovative concrete addresses the challenges of maintaining adequate curing conditions in large-scale projects, maintaining requisite workability, contributing to the overall durability and longevity of concrete structures. For implementing such a versatile material in construction, it is imperative to understand the stress-strain (S-S) behaviour. The primary aim of this study is to develop the S-S curves for TCSCSCC and compare through experimental results. Finite element (FE) analysis based ATENA-GiD was employed for the numerical simulation and develop the analytical stress-strain curves by introducing parameters viz., grade of concrete, tie diameter, tie spacing and yield strength. The stress ratio and the strain ratios are evaluated and compared with experimental values. The mean error is 1.2% with respect to stresses and 2.2% in case of strain. Finally, the stress block parameters for tie confined SCSCC are evaluated and equations are proposed for the same in terms of confinement index.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.12
• /
• pp.2156-2164
• /
• 2017

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered as an antitumor agent owing to its ability to induce apoptosis of cancer cells without imparting toxicity toward most normal cells. TRAIL is produced in poor yield because of its insoluble expression in the cytoplasm of E. coli. In this study, we achieved soluble expression of TRAIL by fusing maltose-binding protein (MBP), b'a' domain of protein disulfide isomerase (PDIb'a'), or protein disulfide isomerase at the N-terminus of TRAIL. The TRAIL was purified using subsequent immobilized metal affinity chromatography and amylose-binding chromatography, with the tag removal using tobacco etch virus protease. Approximately 4.5 mg of pure TRAIL was produced from 125 ml flask culture with a purification yield of 71.6%. The endotoxin level of the final product was $0.4EU/{\mu}g$, as measured by the Limulus amebocyte lysate endotoxin assay. The purified TRAIL was validated and shown to cause apoptosis of HeLa cells with an $EC_{50}$ and Hill coefficient of $0.6{{\pm}}0.03nM$ and $2.41{\pm}0.15$, respectively. The high level of apoptosis in HeLa cells following administration of purified TRAIL indicates the significance and novelty of this method for producing high-grade and high-yield TRAIL.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.28 no.3
• /
• pp.193-202
• /
• 2008

In Korea, domestic consumption of barley as a cereal crop has been decreasing since the 1980s. It has been considered that winter-season crop production could enhance the global competitiveness of domestic livestock industry by providing better quality fodder to livestock and enhancing field use rate. Therefore, the purpose of barley cultivation for cereal food production has been recently replaced by the production of forage barley. Consequently, the area of barley cultivation for forage is markedly increasing in Korea. Forage barley is cultivars especially as forage for cattle. While any type of barley can be used as forage for feeding cattle, forage barleys deliver a higher dry matter yield than conventional feed barley. We have developed forage barley cultivars with cattle's favorite characters such as smooth awn, hood and auricleless types. Cultivar Wooho, Yuyeon, and Dami have smooth awn, hood type spike, and auricleless type plant. We also developed rough awn type barley cultivars, such as Yongyang, Sunwoo, Sangweon, and Soman, showing earlymaturing and high-yielding. They showed about 12 to 10 ton ha－1 in dry matter yield (average 33 ton $ha^{-1}$ in fresh matter yield). And these were evaluated by forage quality which showed a higher grade of silage quality (TDN, ADF, NDF, CP, etc.) for whole crop barley use. Based on these results, it indicated that barley with smooth awn, hooded, and auricleless could be suitable sources in breeding for whole crop forage use.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.60 no.4
• /
• pp.475-483
• /
• 2015

We examined the effects of light colors (wavelength) and light quantities on the yield ratio and quality of cultivated cowpea sprouts. All light colors resulted in a lower cowpea sprout yield ratio compared to the untreated condition (darkness), but were similar in hard seed ratio. All light colors promoted the growth of the epicotyl and root when compared to the untreated condition, but limited the growth of the hypocotyl. White light (458 nm) significantly improved grade by increasing the lightness of the cotyledon and the hypocotyl and the yellowness of the hypocotyl. The Fe content of cowpea sprouts was higher in those grown under red light (632 nm), and the total amino acid content was higher for those grown under yellow light (560 nm), white light (458 nm), and blue light (460 nm) compared to plants grown in the untreated condition (darkness). The yield ratio of cowpea sprouts was lower in the yellow light condition (560 nm) at lower light quantity, but no differences were observed at other light colors and quantities. The lightness and yellowness of cowpea sprouts was higher in the yellow light (560 nm) and red light (632 nm) at lower light quantity, redness was lower. No significant differences were observed in the content of normal and inorganic components according to the light quantities of each light color, except that Fe content was higher in sprouts grown under red light (632 nm) as light quantity increased. Total amino acid content was slightly higher in sprouts grown under white light (458 nm) and blue light (460 nm) as light quantity increased.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.24 no.2
• /
• pp.177-182
• /
• 2004

This experiment was conducted to compare the agronomic characteristics and productivity inintroduced vetch cultivar at the experimental field of Grassland and Forage Crops Division, National Livestock Research Institute from 1999 to 2000. The experiment was arranged in a randomized block design with three replications. The vetch cultivar used in this study were 8 cultivar(Haymaker plus, Common, Capello, Namoi, Victa, Aneto, Popany, Korean milk vetch). Namoi, Victa and Aneto cultivar were died during winter. The cultivar having the fastest flowering date was Korean milk vetch while the flowering date of Common was the latest as 22th May. The average dry matter(DM) content was 14.7% and crude protein(CP) content was 20.9%. Common showed the highest CP content by 23.1% and Korean milk vetch showed the lowest content by 18.0%. Average acid detergent fiber(ADF) and neutral detergent fiber(NDF) content were 33.5 and 42.5% respectively. All cultivar showed the first grade of RFV(relative feed value). The productivity of vetch cultivar were severely different according to the winter hardness. Common showed the highest DM yield by 8,664kg/ha, but the DM yield of Capello and Popany were low by 3,004 and 2,114kg/ha, respectively. The yield of CP and TDN(total digestible nutrient) also was high at Common. The results of this experiments indicated that the productivity of vetch cultivar was effected greatly depending on winter hardness, therefore it was thought winter hardness is the main factor for introducing vetch cultivar.

• Food Science of Animal Resources
• /
• v.30 no.2
• /
• pp.206-215
• /
• 2010

A total of 582 gilts and barrows were analyzed to investigate the regressive relationships to slaughter weight (SW) of variables related to production efficiency and pork quality. Average initial weights and SW were 88.6 and 122.5 kg, respectively, for gilts and 88.7 and 121.4 kg, respectively, for barrows. Average daily gain and gain:feed ratio were not affected by SW. Backfat thickness, which was significantly greater (p<0.01) in barrows (23.3 mm) than in gilts (20.7 mm), increased with increasing SW (0.21 mm/kg; p<0.001). When the 4-notch carcass yield and quality grades were quantified according to an arbitrary 1 point-per-1 notch scale, the former, but not the latter, regressed on SW (-0.64/10 kg; p<0.01). The percent yield of the belly per total lean (overall mean=20.7%) increased with increasing SW (0.37%/10 kg; p<0.001), whereas in other cuts, the SW effect was negligible. The redness of the loin also increased with increasing SW (p<0.05), but other physicochemical characteristics were minimally influenced by SW. In sensory evaluation, effects of SW for fresh and cooked loin, ham, and belly were mostly considered insignificant in terms of quality, albeit statistically significant in several cases. However, positive regressions on SW (p<0.01) of the marbling and acceptability scores of fresh loin as well as the fat:lean ratio of fresh belly were noteworthy. Collectively, SW of approximately 125 kg was maximal for both sexes under the current carcass yield grading, in which 94 kg is the upper weight limit for grade A carcass. However, if the carcass weight limit of the grading was to be removed or broadened, the SW for gilts (but not that for barrows because of their excessive fat content at above 125-kg SW) could be increased to 135 kg or greater without compromising carcass quality.

• Korean Journal of Environmental Agriculture
• /
• v.38 no.3
• /
• pp.145-153
• /
• 2019

BACKGROUND: The 'Gamhong' cultivar, middle season apple with big fruit size and high soluble solid content, has been bred in Korea. However, it was hard to cultivate the cultivar in Korea by serious bitter pit. The relationships between shoot growth, fruit size, and bitter pit may be affected by crop load. This study was conducted for 2 years (7~8 years after planting) to investigate vegetative growth, fruit quality, bitter pit incidence, return bloom, and gross income for optimum crop load of 'Gamhong'/M.9 adult apple tree. METHODS AND RESULTS: The crop load was assigned to 4 different object ranges as follow: 45~64, 65~84, 85~104, and 105~124 fruits per tree. The vegetative growth, average fruit weight, percentage of fruits heavier than 375 g, soluble solid content, and return bloom increased significantly at the crop load range of 45~64 fruits. However, the lowest total gross income per tree may have been caused by the highest bitter pit incidence and the lowest yield per tree in any other crop load range. The total gross income and yield per tree increased significantly at the crop load range of 105~124 fruits and return bloom dropped to 40%, and hence it was possible to occur biennial bearing. It was 85~104 fruits that biennial bearing did not occur and total gross income was as high as the crop load range of 105~124 fruits. Also, the yield of high grade fruits per tree, with fruit weight of 400~499 g and none bitter pit on fruit surface, was highest at the crop load range of 85~104 fruits, compared to other crop load range. CONCLUSION: In considering fruit size, bitter pit incidence, return bloom, and gross income, the optimum crop load range of 'Gamhong'/M.9 adult apple tree in high density orchard was 85~104 fruits per tree.

• Journal of Sericultural and Entomological Science
• /
• v.16 no.2
• /
• pp.1-34
• /
• 1974

These experiments pertain to various factors influencing the quantitative characters of cocoon crops in summer and early autumn seasons. Initially, in order to establish the possible ways of the silkworm rearing more than three times a year in Korea, the author attempted to get further information about the various factors affecting the cocoon crop in every silkworm rearing season. The trials were conducted eleven times a year at four places for three years. The field trial was conducted with 19 typical sericultural farmers who had been surveyed. At the same time the author statistically analyzed the various factors in close relation to tile cocoon crop in autumn season. The effect of guidance on 40 sericultural farmers was analyzed, comparing higher level farmers with lower level farmers ; and the author surveyed 758 non-guided farmers near the guided farmers during both spring and autumn seasons. In addition, another trial on the seasonal change of leaf quality was attempted with artificial diets prepared with leaves grown in each season. It was found that related factors to cocoon crops in summer and early autumn seasons appeared to be leaf quality, and temperature for young and grown larvae. A 2$^4$ factorial experiment was designed in summer season, and another design with one more level of varied temperature or hard leaf added to a 24 factorial experiment was conducted in early autumn. The experimental results can be summarized： 1. Study on the cocoon crops in the different rearing seasons 1) It was shown that earlier brushing of silkworm generally produced the most abundant cocoon crop in spring season, and earlier or later than the conventional brushing season, especially earlier brushing was unfavorable for the abundant cocoon crop in autumn season. 2) The cocoon crop was affected by the rearing season, and decreases in order of sire with spring, autumn, late autumn, summer and early autumn seasons. 3) It was Proved that ordinary rearing and branch rearing were possibles 4 times a year ; in the 1st, 3rd, 8th, and 10th brushing season. But the 11th brushing season was more favorable for the most abundant cocoon crop of branch rearing, instead of the 10th brushing season with ordinary rearing. 2. Study on the main factors affecting the cocoon crop in autumn season 1) Accumulated pathogens were a lethal factor leading to a bad cocoon crop through neglect of disinfection of rearing room and instruments. 2) Additional factors leading to a poor cocoon crop were unfavorable for rearing temperature and humidity, dense population, poor choice of moderately ripened leaf, and poor feeding techniques. However, it seemed that there was no relationship between the cocoon crop and management of farm. 3) The percentage of cocoon shell seemed to be mostly affected by leaf quality, and secondarily affected by the accumulation of pathogens. 3. Study on the effect of guidance on rearing techniques 1) The guided farms produced an average yearly yield of 29.0kg of cocoons, which varied from 32.3kg to 25.817g of cocoon yield per box in spring versus autumn, respectively. Those figures indicated an annual average increase of 26% of cocoon yield over yields of non-guided farmers. An increase of 20% of cocoon yield in spring and 35% of cocoon yield in autumn were responsible. 2) On guided farms 77.1 and 83.7% of total cocoon yields in the spring and autumn seasons, respectively, exceeded 3rd grade. This amounted to increases of 14.1 and 11.3% in cocoon yield and quality over those of non-guided farms. 3) The average annual cocoon yield on guided farms was 28.9kg per box, based on a range of 31.2kg to 26.9kg per box in spring and autumn seasons, respectively. This represented an 8% increase in cocoon yield on farms one year after guidance, as opposed to non-guided farms. This yield increase was due to 3 and 16% cocoon yield increases in spring and autumn crops. 4) Guidance had no effect on higher level farms, but was responsible for 19% of the increases in production on lower level farms. 4. Study on the seasonal change of leaf quality 1) In tests with grown larvae, leaves of tile spring crop incorporated in artificial diets produced the best cocoon crop; followed by leaves of the late autumn, summer, autumn, and early autumn crops. 2) The cocoon crop for young larvae as well as for grown larvae varied with the season of leaf used. 5. Study on factors affecting the cocoon crops in summer and early autumn A. Early autumn season 1) Survival rate and cocoon yield were significantly decreased at high rearing temperatures for young larvae 2) Survival rate, cocoon yield, and cocoon quality were adversely affected by high rearing temperatures for grown larvae. Therefore increases of cocoon quantity and improvement of cocoon quality are dependent on maintaining optimum temperatures. 3) Decreases in individual cocoon weight and longer larval periods resulted with feeding of soft leaf and hard leaf to young larvae, but the survival rate, cocoon yield and weight of cocoon shell were not influenced. 4) Cocoon yield and cocoon quality were influenced by feeding of hard leaf to grown larvae, but survival rate was not influenced by the feeding of soft leaf and hard leaf. 5) When grown larvae were inevitably raised at varied temperatures, application of varied temperature in the raising of both young and grown larvae was desirable. Further research concerning this matter must be considered. B. Summer season 1) Cocoon yield and single cocoon weight were decreased at high temperatures for young larvae and survival rate was also affected. 2) Cocoon yield, survival rate. and cocoon quality were considerably decreased at high rearing temperatures for grown larval stages.

• Food Science of Animal Resources
• /
• v.33 no.1
• /
• pp.125-132
• /
• 2013

In the present study, to determine the effects of terminal sire strains, carcass characteristics, yields of retail cut, and meat quality of 425 pigs were examined. Terminal sires were divided into five strains (D1, D2, B1, B2, and BD) based on the countries of origin and breeds. The strains D1 and D2 showed high grade 1+ appearance ratios and strains B1, B2, and D1 showed high appearance ratios of carcass yield grade A. As for the real retail cut yields of meat, strain D1 showed large real retail cut yields of meat in shoulder, rib, fore leg, loin, belly, tenderloin and hind leg. Moisture contents were significantly higher in strain B1, and protein and fat contents were significantly higher for strain D1 than in the other strains (p<0.05). Shear force values were significantly higher for strain B1 than in the other strains (p<0.05). For meat color properties, the lightness were significantly higher in strains D1, D2, and BD, and the yellowness were significantly higher in strains D1, D2, and BD relative to the other strains (p<0.05). In sensory evaluation, drip of strains D1 and D2 were significantly lower while marbling and overall acceptability were significantly higher in the other four strains (p<0.05). Therefore, when considering the results of the present study comprehensively, using strains D1 and D2 that showed high grade 1+ appearance ratios, large real retail cut yields of belly, significantly higher lightness and sensory evaluation will be helpful to the incomes of producers and farm households.