• Korean Journal of Poultry Science
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• v.14 no.2
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• pp.97-102
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• 1987

The respiratory experiment was made on laying hen fed acclimented to three temperatures of 10, 20, and 30$^{\circ}C$. 1. The FHP of laying hen decreased with increasing room temperature. 2. The feed intake and heat production(HP) all decreased with increasing temperature. However, the highest energy retention was found with optimum temperature (20$^{\circ}C$). 3, The MEm's were 128,110, and 110kcalkg 0.75 for the 10, 20, and 30$^{\circ}C$ of room temperature. The NAME's were 64,78, and 69 percent for the respective room temperature. The results indicated that the highest NAME was obtained with optimum temperature(20$^{\circ}C$). 4. Although there was no significant difference in the nitrogen retention(NR) at different temperatures, the NR was maximum at the optimum temperature(20$^{\circ}C$). 5. The experimental results suggest that in the Bone of thermal neutrality under cooler and hotter conditions heat loss is more dependent on the environmental temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.220-225
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• 1986

This study was conducted to know the effects of temperature and gibberellic acid on the dormancy block-ing of ginseng seeds at different embryo growth stage. Optimum temperature for embryo growth appeared to be I soc at the beginning stage of post ripening (up to dehiscent time), 1$0^{\circ}C$ at middle stage (for 30 days after dehiscence) and 5$^{\circ}C$ at last stage (between 30 and 92 days after dehiscence). And optimum temperature for dehiscence is about 17$^{\circ}C$, also the optimum temperature for dehiscence is higher than that of embryo growth. Germination of ginseng seed with full grown embryo was accelerated at high temperature (25-3$0^{\circ}C$). Germina-tion percentage was 80% at 105th date after dehiscence under 5$^{\circ}C$, 28% at 147th date under 1$0^{\circ}C$, but no germination under the over 15$^{\circ}C$. Gibberellic acid increased the dehiscent rate, whereas the gibberellic acid treatment may not be substituted for effect of low temperature on the germination. Low temperature may be reguired to finish the embryo growth in thickness.

• The Plant Pathology Journal
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• v.15 no.2
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• pp.112-118
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• 1999

Eleven species of Pythium were isolated from leaf blight symptoms on creeping bentgrass (Agrostis palustirs Huds.), Kentucky bluegrass (Poa pratenisis L.) and zoysiagrasses (Zoysia japonica Steud., and Z. matrella (L.) Merr.) planted on golf courses in Korea. Mycelial growth on potato carrot agar medium under various temperature conditions indicated that Pythium species obtained in this study could be divided into four groups based on their responses to temperature conditions. P. vanterpoolii was found to favor low temperature conditions with the optimum temperature of $25^{\circ}$, whereas P. aphanidermatum and P. myriotylum favored relatively high temperature conditions with the optimum temperature of $35^{\circ}$. Other species including P. arrhenomanes, P. catenulatum, P. graminicola, P. oligandrum, P. rostratum, P. torulosum, and P. ultimum were the intermediate group with the optimum temperature of 25~$35^{\circ}$. P. periplocum was similar to the intermediate group but the minimum temperature for its mycelial growth was $15^{\circ}$, which was approximately $5^{\circ}$ above that for the intermediate Pythium spp.group. In the pathogenicity tests conducted in the lab using potted plants, P. aphanidermatum, P.a arrhenomanes, P. catenulatum, P. graminicola, P. myriotylum, P. periplocum, P. rostratum, P. torulosum, P. ultimum, and P. vanterpoolii were found to be pathogenic to creeping bentgrass and Kentucky bluegrass. P. aphanidermatum, P. catenulatum, and P. graminicola were frequently isolated from leaf blight symptoms of creeping bentgrass and Kentucky bluegrass in golf courses during the warm and humid periods in July-August. On the other hand, P. vanterpoolii and P. torulosum were frequently isolated during the cool and humid periods in March-May, suggesting both species might be the major causes of leaf blight occurring in the spring time. Zoysiagrass was susceptible to P. arrhenomanes and the heterothallic Pythium sp. (Ht-F), showing stem and crown rot of turf-grasses at poorly drained areas under coool and humid or rainy conditions. P. oligandrum and the heterothallic Pythium sp. (Ht-L) isolated from creeping bentgrass were avirulent to all species of turfgrasses tested in this study.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.213-216
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• 2021

A gene encoding thermostable cellulase A (TmCelA) was isolated from Thermotoga maritima. The open reading frame of TmCelA gene was 774 bp long which predicted to encode 257 amino acid residues with a molecular weight of 29,732 Da. To examine the biochemical properties, the TmCelA was overexpressed in E. coli BL21, and expressed protein was purified. The optimum temperature of recombinant TmCelA was 90-95 ℃, and the optimum pH of recombinant TmCelA was approximately pH 5.0. Recombinant TmCelA was stable at temperature below 90 ℃.

• Journal of Korean Society of Steel Construction
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• v.17 no.4 s.77
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• pp.491-498
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• 2005

This study involves the development of a computer program to analyze the local buckling stresses for the flange and the web of I-beams under compression at elevated temperatures, and the optimization algorithm to analyze the optimum width-thickness ratios which does not occur their local buckling prior to yield failure. The high-temperature stress-strain relationships of steel used in this study were based on EC3 (Eurocode3) Part1.2 (2000b). In this study, the local buckling stresses and the optimum width-thichness ratios were analyzed considering the influences of the yield stress, local buckling coefficients and width-thickness ratios of the flange and the web. Design examples show the applicability of the computer program developed in this study.

• Journal of the Korean Society of Clothing and Textiles
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• v.8 no.1
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• pp.39-45
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• 1984

The effects of Temperature on the removal of triglyceride were studied with soaps having various chain lengths of alkyl group. Cellophane, polyester film and alkali-treated polyester film were soiled with tripalmitin, tagged with 0" and detergency was evaluated by analysing the tripalmitine on the fabric before and after washing by means of liquid scintillation counting. The results were as following: 1) Triglyceride was completely removed from cellophane in distilled water without surfactant at any temperature, because of the hydrophillic nature of cellulose. The detergency of triglyceride from polyester film fully depended on the state of tripalmitin. The detergency of alkali treated polyester film was better than that of untreated polyester film at lower temperature due to increased hydrophillcity, but worse at higher temperature due to the diffusion of molten tripalmitin into the grooves, formed by alkali treatment. 2) The detergency from polyester film was increased with elevating temperature and after reaching some optimum detergencies, the detergencies were rather decreased with increasing temperature. The temperatures of optimum detergency were shifted to higher with increasing chain length of alkyl group. 3) When the soiled film was baked at $60^{\circ}C$ and $70^{\circ}C$ for 20 min, the detergency vs. temperature was much the same as the case of without-baking. These results indicate that the detergency of triglyceride was largely correlated with the suspending power of surfactants at low temperature and with state of soil and hydrophilicity of substrates with elevating temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.166-171
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• 2017

For high-quality colored rice production, the cultivation environment is a critical factor. The major environmental factor is temperature, which includes the accumulated and average temperature during vegetative and reproductive stages. Generally, during the cultivation period, the temperature can be controlled by shifting the transplanting date. This study was carried out to determine the optimum transplanting date for high-quality red-colored rice production. Four red-colored rice varieties (Jeokjinju, Jeokjinjuchal, Hongjinju, and Gunganghongmi) were used as test materials. The transplanting dates were May 20 and June 5, 20, and 30 in 2015~2016. The most variable factor controlled by the transplanting date was the grain filling rate. The varieties transplanted on June 30 showed low yields owing to the decrease in the grain filling rate. In contrast, the polyphenol content increased with increasing delay in the transplanting date. Collectively, these two results indicate that the optimum transplanting date was June 20. The average temperature for 30 days after the heading date (30DAH) highly affected the polyphenol content. A lower temperature during the 30DAH induced higher polyphenol contents but also caused low yield. The optimum 30DAH temperature for obtaining a higher yield and polyphenol content was $22{\sim}23^{\circ}C$. Using the average 30DAH and accumulated temperatures, the optimum transplanting date was calculated as June 18 to 24 in Miryang region. The optimum transplanting date of Kyeungsangnamdo region was approximately mid-June to early July, and that of Kyeungsangbukdo region was approximately early to mid-June.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.289-296
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• 2021

This study aimed to analyze the optimal transplanting date of the floury endosperm rice varieties Hangaru, Seolgeang, Singil, and Baromi2 allowing to reduce the viviparity rate. The viviparity rate rapidly increased with the mean temperature during the ripening stage. Therefore, to reduce the viviparity rate, we calculated the optimum heading date based on the safe heading date limit in each area so that the ripening stage occurred at lower temperatures. hen, the effects of changes in heading date were monitored by recording the transplanting date and the temperature during the growth period. The transplanting date was highly correlated with the number of heading days in the field. Therefore, the optimum transplanting date was calculated according to the transplanting date in each area. When the accumulated temperature was 700℃, if floury rice was transplanted at the optimum transplanting date, the mean temperature was approximately 20℃. When the accumulated temperature was 900℃, the mean temperature was approximately 18℃. Under these conditions, the viviparity rates of Hangaru, Seolgeang, and Singil rice were lower than 10%. However, Baromi2 showed a high viviparity rate. These results suggest that the viviparity rate of Hangaru, Seolgeang, and Singil rice can be reduced by transplanting at the optimum transplanting date. However, further research is required for pinpointing the optimum transplanting date of Baromi2 rice.

• Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.391-401
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• 2014

Ten feeding trials were conducted to determine and to make the guideline for the optimum feeding rates in olive flounder Paralichthys olivaceus fed extruded pellets at various growth stages at the optimum rearing water temperature. The entire trials were grouped into four growth stages, namely the first stage of juvenile (5 and 9 g), the second stage of juvenile (20, 30, 40 and 50 g), growing (240 and 317 g) and sub-adult (384 and 525 g) stages with 2, 4, 2 and 2 feeding trials, respectively. In the first and second experiments, results indicated that the optimum feeding rates for the first stage of juvenile olive flounder weighing 5 and 9 g could be >5.17 but <5.52% and >4.44 but <4.64% body weight (BW)/day, respectively. In the third, fourth, fifth and sixth experiments, results suggested that the optimum feeding rates for the second stage of juvenile olive flounder weighing 20, 30, 40 and 50 g could be >3.47 but <3.50, >2.85 but <3.53, >2.58 but <3.04 and >2.36 but <2.50% BW/day, respectively. In the seventh and eighth experiments, results showed the optimum feeding rates for growing olive flounder weighing 240 and 317 g to be >1.03 but <1.25 and >0.85 but <1.0 % BW/day, respectively. In the ninth and tenth experiments, the optimum feeding rates in sub-adult olive flounder weighing 384 and 525 g were shown to be >0.69 but <0.7 and >0.55 but <0.8% BW/day, respectively. We will compare these results with the previous studies done by other research groups.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.1
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• pp.3-18
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• 1994

Municipal solid wastes in Korea have physical and chemical properties suitable for composting, but composting has had little practical use in solid waste disposal until now because of a lack of understanding of process control. For practical use of composting, process control must be capable of maintaining good product quality while large quantities are composted in a short period of time. Ventilation control to maintain optimum temperature(Temperature Feedback Aeration Method) is reported to be convenient to operate. The purpose of this study is to analyze process efficiency and optimum temperature in the temperature feedback aeration method for composting of municipal solid wastes. The results of this study show that degradation and drying of substrate in the temperature feedback aeration method are higher than those in the constant aeration method. And the optimum temperature range for composting of solid wastes appears to be $50{\sim}54^{\circ}C$.