• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.730-735
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• 2003

The effect of pathogenicity on trehalose accumulation was studied using six species of entomopathogenic nematodes adapted to either cold or warm temperature conditions. Also, trehalose accumulation was studied by treating nematodes with glycerol or oil at trehalose concentration and mortality of cold temperature $condition(5^{\circ}C)$, S. longicaudum Gl was increased 50% than control. And at trehalose concent and mortality of warm temperature $condition(30^{\circ}C)$, S. glaseri Agr B3 was increased 45%. Intracellular trehalose accumulation was increased with treatment with 20% glycerol or oil. As the final results, the pathogenic duration of nematodes was increased as intracellular trehalose accumulation was increased

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.3
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• pp.301-312
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• 1999

Experiments were carried out to evaluate performance of the cold air distribution systems with an ice storage tank in test room. Cold air distribution systems provide primary air for comfort conditioning or process cooling at coil discharge temperatures$4^{\circ}C$ to$11^{\circ}C$. The application of a cold air distribution system allows for the downsizing of air distribution equipment and central plant equipment when ice storage tank is used. The benefit of a cold air distribution system include a decrease in the floor-to-floor height, increase floor space, reduced building capital costs, reduced energy use and demand. The use of cold air distribution can result in the most cost effective system and is currently being implemented world wise as the new standard in air conditioning systems. In this study, the cold air distribution system is compared with the general ice storage system. Under the same cooling load conditions, experimental results show that the supply air volume of cold air distribution system decrease 38%, and decrease 45% flow rate of brine for the general ice storage system.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.459-463
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• 1994

To improve the quality of rice-cake(Cholpyon), raw starch saccharifying (${\beta}-amylase$ from Bacillus polymyxa No. 26 was used in process of raw rice-cake production. 30g of raw rice flour was incubated with $0{\sim}1,200$ RS units of the enzyme for 5 hr at $45^{\circ}C$, and then steamed and stored for 40 hr at $4^{\circ}C$. In instrumental analysis, control group, which was incubated without addition of (${\beta}-amylase$, was completely hardened after incubation for $12{\sim}24$ hr at $4^{\circ}C$. In contrast, enzyme-treated group was not retrograded, and showed a great differences in hardness, cohesiveness and chewiness. On the other hand, in sensory analysis, the effect of the enzyme treatment was higher values of hardness, moistness, and sweetness than these of control group. Therefore, these results clearly suggested that ${\beta}-amylase$ was fully active to degrade raw rice starch in process of rice-cake production, resulting in improvement of starch retrogradation, good digestibility, and taste.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.524-527
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• 2007

[ $Bi_2Sr_2Ca_{n-1}Cu_nO_x$ ](n=0, 1, 2) thin films have been fabricated by co-deposition at an ultra-low growth rate using ion beam sputtering(IBS) method. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about % K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $ CaCuO_2$ was observed in all of the obtained films.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1115-1121
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• 2007

[ $Bi_2Sr_2Ca{_{n-1}}Cu_nO_x$ ](n=0,1,2) thin fans have been fabricated by co-deposition at an ultra-low growth rate using ion beam sputtering(IBS) method. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.155-159
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• 2016

The objective of this study was to investigate the effect of fermentation temperature on quality characteristics of apple wine. Apple wine mashes were fermented in 15, 20, and $25^{\circ}C$ water bathes for 9 days. The pH levels of all samples were below 4 from 24 h of fermentation until the end. Total acidities of 0.05% acetic acid solution were 7.8, 7.4, and 7.0% in the 15, 20, and $25^{\circ}C$ fermented samples, respectively. The evaporation of esters generated by combining alcohol and organic acids might be the reason for lower total acidity for high temperature fermentation. Alcohol contents of the 20 and $25^{\circ}C$ fermented samples were 6.5 and 6.6% (v/v), respectively, whereas that of the $15^{\circ}C$ fermented sample was 5.6% (v/v) and significantly lower than the others (P<0.05). Methanol contents were 0.68, 0.82, and 1.69 mg/L in the 15, 20, and $25^{\circ}C$ fermented samples, respectively. Fermentation at higher temperatures generated higher methanol content in apple wine. On the other hand, acetaldehyde contents were 3.43, 2.39, and 1.02 mg/L in the 15, 20, and $25^{\circ}C$ fermented samples, respectively, due to the lower boiling point of acetaldehyde ($20.2^{\circ}C$). Based on the results, a fermentation temperature of $20{\sim}25^{\circ}C$ is effective for apple wine fermentation.

• Journal of Power System Engineering
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• v.18 no.4
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• pp.104-111
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• 2014

In this study, EH36 is thick steel plate, which welded by auto $CO_2$ gas welding machine, has been applied on offshore filed. The specimen was examined by indentation tester and it was measured for fracture toughness at $18^{\circ}C$, $0^{\circ}C$, $-20^{\circ}C$ and $-45^{\circ}C$ by low temperature chamber, respectively. The absorbed energy was got on same temperature by Charpy impact tester. The weld surface was observed for watch of changed crystalline structure by optical microscope, and fracture surface of impact test specimen were observed by scanning electron microscope(SEM).

• Korean journal of applied entomology
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• v.34 no.4
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• pp.287-294
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• 1995

Studies were carried out to elucidate the efficacy of exogeneous 20-hydroxyecdysone treatment on terminating pupal diapause in the fall webworm. Hyphantria cunea Drury. And the difference was also investigated between normal adult development and post-diapause development after 20-hydroxyecdysone treatment. In the diapause termination rate of pupae treated with 20-hydroxyecdysone after storage for various periods at 16L:8D and $25\pm$$1^{\circ}C$, at the highest rate was observed from the group stored for the longest period and the lowest rate from those stored for 1.5 months. The time needed for adult emergence was inversely proportional to the chilling (at $0\pm$$1^{\circ}C$) period, and the longer its exposure period at low temperature, the higher its sensitivity to 20-hydroxyecdysone treatment. Pupal diapause duration was almost the same, regardless of storage period in the total darkness or at the photoperiod of 16L:8D, and also they successfully emerged to adult even without any experience at low temperature. The oxygen consumption rate in normally developing pupae showed nearly a typical U-form. But, that of diapausing pupae treated with 20-hydroxyecdysone slowly increased and jumped 14 days after the treatment. Pupal diapause began before formation of adult tissues, an a timing of adult tissue formation coincided with ascending timing of the metabolic rate in both normally developing pupae and diapausing pupae treated with 20-hydroxyecdysone. The diapausing pupae treated with 20-hydroxyecdysone was similar to normally developing pupae in band patterns of proteins from haemolymph or fat body.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.1
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• pp.56-64
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• 2001

Composting of livestock feces is economic and safe process to decrease the possibility of direct leakage of organic pollutants to ecosystem from commercial and environmental point of view. This study was conducted with three different experiments related to composting of livestock feces. The purpose of experiment 1 was to investigate changes of characteristic of compost pile during composting period by low temperature in cold season. To compare composting effect of experimental compost pile and control pile exposed in cold air, experimental compost piles were warmed up by hot air until their temperatures were reached at $35^{\circ}C$. Sawdust, Ricehull and Ricestraw were mixed with livestock feces as bulking agent. The highest temperatures of compost pile during composting period were in sawdust, rice hull, rice straw, and control were $75^{\circ}C$, $76^{\circ}C$, $68^{\circ}C$, $45^{\circ}C$ respectively. Moisture content, pH, C/N and volume of compost were decreased during composting period. Experiment 2 was carried out to study utilization effect of compost by plant. A corn was cultivated for 3 years on fertilized land with compost and chemical fertilizer. The amount of harvest and nutrition value of corn were analyzed. In first year of trial, the amount of harvest of corn on land treated with compost was lower by 20% than that of land treated with chemical fertilizer. In second year, there was no difference in yield of com between compost and chemical fertilizer. In third year, the yield of com on land fertilized with compost was much more than that of land fertilized with chemical fertilizer. The purpose of experiment 3 was to estimate the decrease of malodorous gas originating from livestock feces by bio-filter. Four types of bio-filters filled with saw dust, night soil, fermented compost and leaf mold were manufactured and tested. Each bio-filter achieved 87-95% $NH_3$ removal efficiency. This performance was maintained for 10 days. The highest $NH_3$ removal efficiency was achieved by leaf mold on the first day of operation period. It reduced the concentration of $NH_3$ by about 95%. Night soil and fermented compost showed nearly equal performance of 93 to 94% for 10 days from the beginning of operation. The concentration of hydrogen sulfide and methyl mercaptan originating for compost were equal to or less than $3mg/{\ell}$ and $2mg/{\ell}$, respectively. After passing throughout the bio-filter, hydrogen sulfide and methyl mercaptan were not detected.

• Korean Journal of Weed Science
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• v.32 no.1
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• pp.35-43
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• 2012

The objective of this research was to confirm the difference in physiological responses to environmental stresses such as chilling, high temperature, NaCl, and chemical stress (paraquat) in Protox inhibitor resistant-transgenic rice (MX, PX, and AP37) and its non-transgenic counterpart (WT). Transgenic and non-transgenic rice plants were exposed to a chilling temperature of $5^{\circ}C$ for 1 day or a high temperature of $45^{\circ}C$ for 4 days and allowed to recover at $25^{\circ}C$ for 6 days after the chilling treatment or 8 days after the high temperature treatment. Leaf injury, shoot fresh weight, porphyrin biosynthesis substances, and chlorophyll content were investigated in transgenic and non-transgenic rice at 6 days after 0.5% and 1% NaCl treatments or at 5 days after 0~300 ${\mu}M$ paraquat treatments. No significant difference in leaf injury and shoot fresh weight were observed between transgenic and non-transgenic rice during chilling and recovery. Plant height and shoot fresh weight were also similar between transgenic and non-transgenic rice during the high temperature and recovery period (0~5 days). However, plant height and shoot fresh weight in transgenic rice line MX and PX were lower than in non-transgenic rice at 6 days for recovery. Leaf injury, chlorophyll, and Mg-Proto IX ME contents had no significant difference between transgenic rice and non-transgenic rice after NaCl treatment, but Proto IX content for AP37 and shoot fresh weight for PX and AP37 in 0.5% NaCl treatment were significantly reduced compared with non-transgenic rice. There was no difference in leaf injury and shoot fresh weight when comparing transgenic rice and non-transgenic rice after paraquat treatment. Although transgenic rice and non-transgenic rice showed a little difference at a particular measurement period in certain environmental stresses, there was generally no difference in physiological responses between transgenic rice and non-transgenic rice.