• 한국초전도학회:학술대회논문집
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• 2009.07a
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• pp.108-108
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• 2009

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.5
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• pp.457-461
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• 2010

To estimate the effect of selective breeding on the improvement of growth in olive flounder Paralichthys olivaceus, we compared the growth of a strain selected for rapid growth to that of an unselected strain from a commercial hatchery. The fish strains were fed with either moist pellets (MP) (dry matter, 59.8% crude protein; 14.1% lipid) or extruded pellets (EP) (dry matter, 50.4% crude protein; 13.8% lipid) for 190 days and were reared under similar conditions. The mortality rates were less than 2% and were not significantly different among the experimental groups. The growth rate of the selected fish was significantly greater than that of the unselected fish regardless of the diet type, and both strains fed MP grew significantly faster than those fed EP. The selected fish consumed more feed than the unselected fish. However, there was no significant difference in the feed efficiency between the selected and unselected fish. These results demonstrate that the selected fish exhibited superior growth rates, and that this was associated with a greater intake of food. Thus, selective breeding may be useful for improving the growth of commercial olive flounder.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.145-150
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• 2007

This study was conducted to elucidate the mid-growth of Norway spruce at the age of 27 and select the superior provenances in Korea. Growth performance of twenty-four provenances from Germany and Rumania were investigated in four plantations. Significant differences were found in growth (height, DBH, volume) with plantations. Maximum growth were detected on plantation Chuncheon which located in most northern area, and minimum growth were detected on plantation Wanju located in most southern area. The rank of height in provenances has fluctuated, but superior/inferior groups have been almost fixed. 840-23, 840-10, 840-19 in Germany, G1-64-57, G1-64-54 in Rumania proved excellent provenances. Height in early stage positively correlated with that in late stage. The growth was positively correlated with latitude and altitude of plantations, but negatively correlated with temperature.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1060-1068
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• 2019

This work aims to establish a model of a primary water stress corrosion crack growth rate of Alloy 690 material for the head penetration nozzles of Korean pressurized water reactors. The test material had an inhomogeneous microstructure with bands of fine-grains and intragranular carbides in the matrix of coarse-grains, which was similar to the archive materials of the head penetration nozzles. The crack growth rate was measured from the strain-hardened materials as a function of the stress intensity factor in simulated primary water at various temperatures and dissolved hydrogen contents. The effects of strain-hardening, temperature, and dissolved hydrogen on the crack growth rate were analyzed independently, and were then introduced as normalizing factors in the crack growth rate model. The crack growth rate model proposed in this work provides a key element of the tools needed to assess the progress of a stress corrosion crack when detected in thick-wall Alloy 690 components in Korean reactors.

• BMB Reports
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• v.28 no.5
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• pp.437-442
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• 1995

The potency of yeast-derived methionyl-free human growth hormone (rhGH), which was obtained by removal of the N-terminal Met from methionyl-hGH, was estimated by in vitro and in vivo assays. In radio-receptor assay where the binding affinity of growth hormone to the receptor was estimated, the recombinant hGH showed 2.9 international units (IU) per mg of specific activity. In contrast, pitUitary-derived human growth hormone had a slightly lower receptor binding activity (2.5 IU/mg) compared with recombinant growth hormone. For the in vivo assay, efficacy of rhGH was tested by use of hypophysectomized rats, in which pituitary organs were surgically removed, resulting in the termination of growth hormone secretion. The weight-increase in rats by the injection of rhGH was almost identical to the result obtained by the injection of the same amount of pituitary-derived (international standard) hGH. A comparision of the secondary structures of rhGH and rMet-hGH by circular dichroism spectrophotometer demonstrated that the removal of the methionyl residue from rMet-hGH did not exert any effect on the structure of the growth hormone. In conclusion, methionyl-free human growth hormone produced from yeast was highly potent in biological activity and maintained a legitimate three dimensional structure.

• International Journal of Railway
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• v.5 no.3
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• pp.129-134
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• 2012

Contact fatigue damages on the rail surface, such as head checks and squats are a growing problem. The fatigue cracks forming on the contact surface grow according to load and lubricating conditions and may end up breaking the rail. Rail fracture can be avoided by preventing the cracks from reaching the critical length. Therefore, the crack growth rate needs to be estimated precisely according to the conditions of the track and load to develop a maintenance plan against rail damages. Therefore, it is important to understand the mechanism of cracks initiation and growth on a rail due to repetitive rolling contact. In this study, we have investigated the crack growth behavior on the rail surface by using the twin-disc tests and the finite element analysis.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.215-218
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• 1997

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.449-461
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• 1996

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.249-254
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• 2016

The purpose of this study is to estimate genetic parameter and growth traits by sex of Pacific abalone, Haliotis discus hannai. The abalone 10 family produced using 1:1 mating system of male and female for analyses of sex ratio and growth traits (shell length, shell width, and total weight) by sex. Overall mean in phenotypic traits at 30-month-old showed 85.01 mm of shell length, 57.49 mm of shell width and 73.34 g of total weight respectively. The sex ratio (female : male) was 1:0.93 (n = 191:177). The values of growth traits by sex showed significant difference (P < 0.05). The each value of female growth traits were shown to be higher than the values of male growth traits. The heritability of growth traits by sex were estimated that the heritability of female growth traits are higher than male that. The results suggest a possibility of improving the growth of cultured abalone using selection breeding by sex.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.377-386
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• 2008

The growth performance of Eastern white pine (Pinus storbus L.) was studied with six provenances in four plantations. All growth performances were significantly different among provenances and plantations. The most outstanding source in volume growth at age 39 is North Carolina in all plantations and this trends had been started from four years old seedlings. In plantations, the growth is best in ChunCheon plantation while that is worst in GunPo plantation. The Effect of plantations was thought to be larger than that of provenances growth of P. strobus. A pattern of growth by ages was different by among plantations and even ate age about 40, the growth was still vigorous. Annual precipitation, foggy days, altitude and sand contents in soil are positively correlated with growth and the correlations between by ages were very high.