• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.205-218
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• 1990

A general model was developed to simulate cattle growth and beef production. The present model was constructed, based on ARC metabolizable energy system in principle, and incorporated up-to-date knowledge and information into previous models, which were reported by Sanders and Cartwright (1979a,b) and Kahn (1982). The model may apply to cover a wide range of genetic and environmental conditions, because many factors relating to cattle growth and beef production are taken into consideration. The model may provide better understanding of various components and processes of beef cattle production systems.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.153-158
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• 2000

Atomic Force Microscope (AFM) was used to study cross sectional profiles and dimensions of fatigue striations in 2017-T351 aluminum alloy. Their widths (SW) and heights $(SH,\;SH_h)$ were measured from the cross sectional Profiles of three-dimension AFM images. The following results that will be helpful to understand the fatigue crack growth mechanism were obtained. (1) Coincidence of the crack growth rate with the striation width was found down to the growth rate of $10^{-5}$ mm/cycle. (2) The relation of $SH={\alpha}(SW)^{1.2}$ was obtained. (3) The ratio of the striation height to its width SH/SW and did not depend on the stress intensity factor range ${\Delta}K$ and the stress ratio R. From these results, the applicability of the AFM to nano-fractography is discussed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.607-611
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• 2016

This study was conducted to investigate the effects of different water temperatures on growth, survival, biochemical composition, and blood physiological parameters of juvenile mandarin fish Siniperca scherzeri. Feed-trained juvenile fish were subjected to four water temperatures (20, 23, 26 and 29℃) with two replicate groups. The fish were fed to apparent satiation twice daily using a formulated diet containing 55% crude protein and 6% crude lipid. After the 8-week feeding trial, survival was >96% in all groups. Weight gain and feed efficiency of fish reared at 26 and 29℃ were higher than those reared at 20℃. The protein efficiency ratio, daily feed intake, and whole body proximate composition were not affected by water temperature. These results indicate that a suitable water temperature range for optimal growth and feed efficiency of juvenile mandarin fish is 26-29℃ under these experimental conditions.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.4
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• pp.58-64
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• 2004

The purpose of this study is to predict the behavior of fatigue crack propagation as one of fracture mechanics on the compressive residual stress. We got the following characteristics from fatigue crack growth test carried out in the environment of room temperature and low temperature at $25^{\circ}C$, -6$0^{\circ}C$, -8$0^{\circ}C$, and -10$0^{\circ}C$ in the range of stress ratio of 0.3 by means of opening mode displacement. There is a difference between shot peened specimen and unpeened specimen. Fatigue crack growth rate of shot peened specimen was lower than that of unpeened specimen. Shot peening is improve the resistance of crack growth by fatigue that make a compressive residual stress on surface. That is the constrained force about plasticity deformation was strengthened by resultant stress, which resulted from plasticity deformation and compressive residual stress in the process of fatigue crack propagation. Temperature goes down, fatigue crack growth rate decreased.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.565-570
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• 1994

The pullulan production and morphological change of Aureobasidium pullulans ATCC 9348 were investigated both in batch fermentation and in continuous fermentation. The best carbon source for pullulan production was sucrose among seven different carbon sources. The pullulan production of A. pullulans was increased with increasing the carbon to nitrogen ratio of the medium using sucrose as a carbon source. In batch fermentation, production of pullullan occurred following exhaustion of the nitrogen source from the medium. The continuous fermentation showed that the pullulan production was closely parallelled with cell growth and was most effective at a dilution rate of 0.06~0.07 hr$^{-1}$-. The ratio of yeast-like cells(blastospores) of A. pullulans increased with the increase of growth rate, and reached 100% over the growth rate of 0.07 hr$^{-1}$. The growth rate, within a certain range, affected not only on the cell morphology, but on the specific pullulan productivity of A. pullulans.

• Korean Journal Plant Pathology
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• v.10 no.4
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• pp.270-276
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• 1994

Mycelial growth resistant isolates of Botryosphaeria dothidea to benomyl showed 99~79% spore germination on the PSA media supplemented with 200~2,100 $\mu\textrm{g}$/ml of carbendazim and thiophanate-methyl to manifest the high cross-resistance in spore germination. Mycelial growth, 23~9 mm in colony diameter, also manifested the high cross-resistance of mycelial growth together with similarity of spore forming cross-resistance. Benomyl resistant isolates BR1, BR2 and BR3, grew 23~10 mm in colony diameter at 330~3,000 $\mu\textrm{g}$/ml of captafol, captan and oxine-copper showing the high double resistance of mycelial growth and spore formation with minor difference. However, within concentration range of the 3 fungicides tested, germinations of all the tested isolates were completely suppressed to show no double-resistance in the fungal spore germination.

• The Korean Journal of Food And Nutrition
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• v.12 no.6
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• pp.569-574
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• 1999

Response surface methodology(RSM) was applied to determine the optimum heating conditions(tem-perature and time) for the inactivation of bacteria associated with food hygiene. Coefficients of determinations(R2) for the cell growth were 0.9155(P<0.05) in Pseudomonas aeruginosa 0.8997(P<0.05) in Escherichia coli 0.9690(P<0.01) in Salmonella typhimurium 0.9393(P<0.05) in Enterobacter aerogenes and 0.7905 in Vibrio parahaemolyticus. The growth of strains was significantly affected by the temperature and time and reaction to temperature was most closely correlated to the inhibition of growth. On the basis of superimposed contour maps of cell growth the optimum range of heating conditions were 55.62-6$0^{\circ}C$ and 19.25-30 min.

• Korean Journal of Crystallography
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• v.11 no.3
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• pp.151-156
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• 2000

Yb/YAG single crystals were grown from the melt composition of Y/sub 1-x/Yb/sub x/)₃Al/sub 5/O/sub 12/ where x equal to 5, 10, 15, 20, 25, 33, 50, 75 and 100 at % by floating zone method. Optimum growth parameters to get high quality single crystals were 3.5 mm/h of growth rate and 20 rpm of rotation rate under the N₂ atmosphere. After the growth, color of crystals was appeared with pale blue due to the lack of oxygen, but it was disappeared after annealing at 1450℃ for 2 hr. Absorption coefficients were linearly increased depending on the concentration of Yb/sup 3+/ ions. Broad emission band was measured in the range of 1020 to 1050 nm with the peak intensity at 1031 nm and 1051 nm because of ²F/sub 5/2/(1)→²F/sub 7/2/(3) and ²F/sub 5/2/(1)→²F/sub 7/2/(4) transition respectively. When Yb/sup 3+/ ions were substituted with high rates, there were tendency to decrease the measured fluorescent lifetime for Yb ions depending on the concentration of Yb/sup 3+/ ions.

• Korean Journal of Microbiology
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• v.9 no.3
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• pp.95-102
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• 1971

The growth characteristics of Candida tropicalis KIST 351 on gas oil substrate under different culture conditions were investigated and the preliminary animal feeding experiments using this yeast as a partial substitute of fish meal was also conducted. The yeast assimilates effectively n-paraffins in gas oil ranging from $C_{16}$ to $C_{16}$ with its maximum cell growth at $33^{\circ}C$ and pH 5.5 with aeration of 3 vvn and agitation of 900 rpm. The optimal concentrations of nitrogen sources, $HK_2PO_4$ and $Na_2HPO$ were 4, 2 and 0.5g/1, respectively. Ferrous sulfate, manganese sulfate and zinc sulfate showed positive effect to cell growth with the optimal range of 5-10 ppm. In the feeding experiment with 3 and 5% incorporation of the gas oil grown yeast, neither adverse effects on growth of chicks nor toxic effect were observed. Protein content of the dried cell was 58.8% and its amino acid composition compared well with other single-cell protein products and FAO reference protein.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.271-280
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• 2018

The ectomycorrhizal basidiomycete Tricholoma is one of mushroom groups that cannot be cultivated artificially. To use this mushroom as applicable resource for food production, it is necessary to obtain information about their mycelial growth properties in various environmental conditions. This study investigated the mycelial growth of four domestic isolates of Tricholoma species (T. bakamatsutake, T. fulvocastaneum, T. matsutake, T. terreum) at different physical and chemical conditions. The optimal physical conditions for their mycelia growth were found to be a temperature range of $20{\sim}25^{\circ}C$ and a pH range of 4.0~7.0 in dark condition. The growth of T. matsutake was retarded at high temperature ($30^{\circ}C$). Tests to determine the chemical factors that affected mycelial growth showed that the four Tricholoma spp. grew 1% saline. T. matsutake grew in up to 2% saline. In the presence of various heavy metals (50 ppm) and pesticides (suppliers' recommended concentration), mycelial growth was inhibited the most by cadmium and emamectin benzoate, respectively. However, all the four Tricholoma spp. grew with $Cu^+$. The growth of T. matsutake was not inhibited by abamectin, acetamiprid, and thiacloprid. Extracellular enzyme activities of amylase and ${\beta}$-glucosidase were detected only in T. bakamatsutake and T. fulvocastaneum. The results of the present study allowed us to determine suitable or harmful environmental conditions for the mycelial cultivation of the Tricholoma spp.