• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.685-688
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• 2006

As the concrete structure being large-sized and/or high-strengthened, the control of the hydration and curing temperature is made much account. This study, analysing the concrete temperature history from cylindric specimen and mock-up structures, investigates the effect of the early age curing condition and the optimum method of curing temperature control on mass concrete.

• Elastomers and Composites
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• v.48 no.2
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• pp.103-113
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• 2013

The properties of the rubber composites containing a silane and silica were evaluated by changing the mixing time and temperature, in order to find the optimum mixing conditions. Characteristics of the compounds were evaluated after mixing at $120^{\circ}C$, $140^{\circ}C$, and $160^{\circ}C$ with various mixing time. With increasing of mixing time, mooney viscosity decreased while the bound rubber contents of the compounds increased. Viscosity rise by increased mixing time was bigger at low temperature and the higher the mixing temperature the faster in the formation of bound rubber. With lower mixing temperature of $120^{\circ}C$, cross-linking rate was almost constant. Dynamic viscoelastic properties and dispersity of the compound showed that dispersion of ingredients and reaction was not sufficient with the mixing time of less than 10min. On the contrary, with high temperature, it was obvious that good dynamic and physical properties could be obtained due to sufficient coupling reaction, however it was thought this high temperature is not optimum because of sensitive cross-linking rate and physical properties and excessive formation of bound rubber. Consequently, it was confirmed that the mixing condition of 10min at $140^{\circ}C$ was optimum for the silane coupling reaction and dispersion of functionalized S-SBR containing silica and silane.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.107-112
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• 2004

The combining abilities in the 5 newly evolved thermo tolerant breeds viz., SR6, SR7, SR8 SR9 and SR10 of silkworm Bombyx mori L. and their 15 hybrids were made in a line${\times}$tester crossing programme. Data were analysed for seven quantitative traits i.e., pupation rate, cocoon yield, cocoon weight, cocoon shell weight, cocoon shell ratio, filament length and raw silk percentage under optimum room temperature $(25{\pm}{1^{\circ}C})$ conditions (In case of high temperature $(36{\pm}{1^{\circ}C})$ stress conditions five economic traits except filament length and raw silk percentage) with 3 widely adapted testers i.e., KA, CSR2 and CC1 as lines (females) and testers (males) respectively. The performance at high temperature and low humidity conditions aye only taken into consideration for selecting the best lines/hybrids. Among the lines SR6 exhibited positive General combining ability (GCA) effects for pupation rate, cocoon yield, cocoon weight and cocoon shell ratio traits, followed by SR7 for pupation rate, cocoon yield and cocoon shell weight and cocoon shell ratio. Among testers, KA exhibited positive GCA effects for two quantitative traits cocoon yield, cocoon weight and CSR2 for cocoon shell weight and cocoon shell ratio under adverse temperature conditions. The hybrid SR6${\times}$CC1 and SR7${\times}$CSR2 exhibited significant positive Specific combining ability (SCA) effects for majority of the traits in high temperature stress conditions of rearing. The better parent value of heterosis(Heterobeltiosis) was exhibited by the hybrid SR6${\times}$CC1 for pupation rate, cocoon yield, cocoon weight and cocoon shell weight and SR7${\times}$CSR2 for all the trails evaluated under high temperature conditions. Based on the results, the lines SR6 and SR7 was judged as best combiners and the hybrids SR6${\times}$CC1 and SR7${\times}$CSR2 can be selected for commercial exploitation in tropical climate.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.177-182
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• 2013

A genus Camelina has been attracted as a promising oil crop, especially available in drought and marginal conditions. Due to more demands on arable land for bioenergy crops, price of agricultural products has been a challengeable issue. In that respect, development of Camelina crop with higher germination rate and germination energy can be a strategy to secure seedling establishment, nutrient uptake and long vegetative period. In order to be easily available in the field and laboratory conditions, Camelina seed needs to be optimized for its germination temperature. Germination temperature regime was in a range of 8 to $32^{\circ}C$ initially, and consecutively narrowed down to 8 to $20^{\circ}C$. Based on the temperature range, Camelina germinated greater than 96% at $8-16^{\circ}C$ in two weeks after sowing, but germination rate started to decrease at the higher than $24^{\circ}C$ and was significantly low at higher than $32^{\circ}C$. In terms of rapid time to reach the maximum germination rate and greater germination energy, temperature ranged from 12 to $16^{\circ}C$ was found to be desirable for Camelina germination. Although germinationa rate was greater at $16^{\circ}C$, lower temperature close to $12^{\circ}C$ would be favored for the field conditions where greater root growth leading to healthier seedlings and better nutrient or water availability is considerably demanded.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.2
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• pp.102-107
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• 2003

This study puts focus on the optimization of growth temperature of CIGS absorber layer which affects severely the performance of solar cells. The CIGS absorber layers were prepared by three-stage co-evaporation of metal elements in the order of In-Ga-Se. The effect of the growth temperature of 1st stage was found not to be so important, and 350$^{\circ}C$ to be the lowest optimum temperature. In the case of growth temperature at 2nd/3rd stage, the optimum temperature was revealed to be 550$^{\circ}C$. The XRD results of CIGS films showed a strong (112) preferred orientation and the Raman spectra of CIGS films showed only the Al mode peak at 173cm$\^$-1/. Scanning electron microscopy results revealed very small grains at 2nd/3rd stage growth temperature of 480$^{\circ}C$. At higher temperatures, the grain size increased together with a reduction in the number of the voids. The optimization of experimental parameters above mentioned, through the repeated fabrication and characterization of unit layers and devices, led to the highest conversion efficiency of 15.4% from CIGS-based thin film solar cell with a structure of Al/ZnO/CdS/CIGS/Mo/glass.

• Asian Journal of Turfgrass Science
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• v.9 no.3
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• pp.253-260
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• 1995

This study is aimed to understand the effects of temperature, light and GA soaking treatment on the seed germination of perennial ryegrass 'Dandy', creeping hentgrass 'Penlinks', tall fescue 'Arid' and Kentucky hluegrass 'Nasaw'. These experiments are carried in vitro, and their results obtained are summarized as the followings ; The optimum temperature for seed germination of perennial ryegrass 'Dandy' was found to he ranged at 20~30$^{\circ}C$, and the optimum temperature for germination of creeping bentgrass 'Penlinks', tall fescue 'Arid' and kentucky bluegrass 'Nasaw' seeds was found to be ranged at 20~25$^{\circ}C$, whereas the germination percentage under the below or above temperature of this range decreased. The germination of perennial ryegrass 'Dandy' and tall fescue 'Arid' seeds showed no effect on light, and while the germination percentage of creeping hentgrass 'Penlinks' increased more highly under the dark condition than under the light condition. The germination percentage decreased according to the higher temperature. The germination of Kentucky bluegrass 'Nasaw' seeds increased more highly under the dark condition than under the light condition at 20~25$^{\circ}C$, whereas the germination percentage under the dark condition at 15$^{\circ}C$ and 30$^{\circ}C$ decreased. In case of GA soaking treatment of seeds, all the cool season turfgrasses tested showed their own promoting effects on seed germination. The early germination of tall fescue 'Arid' was good without the soaking times. Creeping bentgrass 'Penlinks' and perennial ryegrass 'Dandy' had re-spectively the highest germination percentage at 10min and 1hr soaking treatment, and the longer the soaking time, the lesser the germination percentage. Kentucky bluegrass 'Nasaw' obtained the best results at 24has soaking treatment, and the longer the soaking time, the better the ger-mination percentage.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.6
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• pp.1315-1321
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• 2014

We investigated the optimum salinity and temperature conditions for the mass culture of small rotifer, Proales similis. In the salinity experiment ranging from 1, 5, 10, 15, 20, 25 and 33‰, growth tended to decrease with salinity increase. Most agreeable salinity for rotifer growth was 1‰ in which maximum density and specific growth rate (SGR) were obtained. In the temperature experiments ranging from 15, 20, 25, 30 and $35^{\circ}C$, continuous growth of rotifer populations was found up to $35^{\circ}C$. The highest maximum density (2,060 inds./mL) of rotifer was observed at $25^{\circ}C$ in given temperature regime. Also, the SGR of females showed increasing tendencies with the increase of temperature. These results suggest that the optimum salinity and temperature for mass culture of P. similis may be 1‰ and $25^{\circ}C$, respectively.

• Transactions of the Korean Society of Mechanical Engineers
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• v.5 no.2
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• pp.151-157
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• 1981

The concept of available evergy has been adopted in terms of effectiveness for and evaporator of vapor power cycle. This kind of practice is emphasezed in a case of heat and power cogeneration in order to find optimum condition for the energy utilzation of the exhaust gas. It has beed shown that the optimum condition can be given in terms of the saturation pressure or the saturation temperature of the working fluid. Similar method has been applide to show that the effectiveness is increased asymptotically with the number of evaporator stanges.

• Korean Journal of Microbiology
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• v.14 no.3
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• pp.99-99
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• 1976

Some properties of xylanase produced by Pleurotus ostreatus during its gorwth in a rice straw medium were investigated. The results are summarized as follows : 1) The optimum pH of xylanase was 5.0 and the stable pH ranged from 4.5 to 6.0. 2) The optimum temperature for the xylanse was around $50^{\circ}C$ and the xylanse activity was completely lost in 10 minutes at $70^{\circ}C$ 3) The activity of xylanse was inhibited by managanous ion, but was increased by other metalic ions. Especially K, Mg and Ca ions considerably increased the activity.

• Korean Journal of Microbiology
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• v.14 no.3
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• pp.93-104
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• 1976

Some properties of xylanase produced by Pleurotus ostreatus during its gorwth in a rice straw medium were investigated. The results are summarized as follows : 1) The optimum pH of xylanase was 5.0 and the stable pH ranged from 4.5 to 6.0. 2) The optimum temperature for the xylanse was around $50^{\circ}C$ and the xylanse activity was completely lost in 10 minutes at $70^{\circ}C$ 3) The activity of xylanse was inhibited by managanous ion, but was increased by other metalic ions. Especially K, Mg and Ca ions considerably increased the activity.