• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.03a
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• pp.139-148
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• 1994

An experimental study on material characterization and mechanical properties of SMC(Sheet Molding Compounds) compression molding parts was carried out. Simple compression test using grease oil as a lubricant was carried out to characterize flow stress of SMC at elevated temperatures. Two different mold temperatures, 130$^{\circ}C$ and 150$^{\circ}C$ and two different mold speeds, 15, 45mm/min were used for preparing the specimen of SMC compression molding parts. Surface roughness, tensile, and 3-point bending tests were used to determine the effects of molding temperatures and speeds on mechanical properties of compression molded SMC parts.

• Journal of the Korean Ceramic Society
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• v.27 no.3
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• pp.430-436
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• 1990

Glasses of different compositions were synthesized by substituting each component of 56ZrF4-14BaF2-6LaF3-4AlF3-20NaF(ZBLAN) with HfH4, SrF2, GdF3, InF3 and LiF3, each of similar size and chemical property with the component being substituted, respectively. The heating rate used in the DSC runs was 10K/min. All ofthe glasses exhibit glass transition temperatures of 510$\pm$10K, while crystallization temperatures vary between 625 and 720K depending upon different glass compositions. For most glasses crystallization temperatures obtained while cooled are lower than those obtained while heated, but InF3 or SrF2 containing glasses showed opposite trend. HBLAN, ZHBLAN and ZHBLANLi glasses, which were made by substituting HfH4, LiF for ZrF4 and NaF of ZBLAN respectively, showed improvement in the glass stability.

• Journal of Mechanical Science and Technology
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• v.15 no.7
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• pp.839-846
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• 2001

Some deep drawing characteristics at elevated temperatures were investigated for the SCPI steel sheets by using a Cr-coated die. For this investigation, six different temperatures between room temperature and 250$\^{C}$, and six different drawing ratios ranging from 2.4 to 2.9 were considered. As a result, the limiting drawing ratio, the maximum drawing force and the maximum drawing depth were found to be affected sensitively by temperature, and more stable through-thickness strain distribution was observed at elevated temperatures. Some experimental results compared favorably with theoretical results obtained by using the finite element method.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2396-2403
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• 1994

An experimental study on material characterization and mechanical properties of SMC(Sheet Molding Compounds) compression method parts was carried out. Simple compression test using grease oil as a lubricant was carried out to characterize flow stress of SMC at elevated temperatures. Two different mold temperatures, $130^{\circ}C{\;}and{\;}150^{\circ}C$ and two different mold speeds, 15, 45 mm/min were used for preparing the specimen of SMC compression molded parts. Surface roughness, tensile, and 3-point bending tests were used to determine the effects of molding temperatures and speeds on mechanical properties of compression molded SMC parts. Orientation and distribution of glass fiber in the compression molded SMC parts were also investigated by photographing the burnt flat specimen and taking SEM(Scanning Electron Microscope) of cross-sectional T-specimen.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.4
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• pp.287-293
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• 2008

The purpose of this study was to clarify the effects of air and ceiling temperatures on a type of ceiling cooling system that involves cool water circulation. The experiment is conducted in summer. The subjects (11 young females) are exposed to the following conditions: combinations of air temperatures $(27^{\circ}C,\;29^{\circ}C,\;31^{\circ}C)$ and ceiling temperature of $(22.7^{\circ}C,\;23.7^{\circ}C,\;24.7^{\circ}C)$ in still air and RH 50%. The following results were obtained; the thermal sensation vote is neutral at a mean skin temperature of $34.5^{\circ}C$. The ceiling temperature affected different parts of the body. For example, the forehead, scapula and abdomen produced different skin temperatures. Thermal comfort vote was rated as comfortable at high temperature environment. The satisfaction from the ceiling temperature was valued comfortable zone in this experiment. Mean skin temperature showing higher thermal neutrality temperature than existing studies for floor and wall radiation cooling results.

• Nuclear Engineering and Technology
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• v.50 no.5
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• pp.731-737
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• 2018

In this research paper, the thermal transport in thorium dioxide is investigated by using nonequilibrium molecular dynamics. The thermal conductivity of bulk thorium dioxide was measured to be 20.8 W/m-K, confirming reported values, and the phonon mean free path was estimated to be between 7 and 8.5 nm at 300 K. It was observed that the thermal conductivity of thorium dioxide shows a strong dependency on temperature; the highest thermal conductivity was estimated to be 77.3 W/m-K at 100 K, and the lowest thermal conductivity was estimated to be 4.3 W/m-K at 1200 K. In addition, by simulating thorium dioxide structures with different lengths at different temperatures, it was identified that short wavelength phonons dominate thermal transport in thorium dioxide at high temperatures, resulting in decreased intrinsic phonon mean free paths and minimal effect of boundary scattering while long wavelength phonons dominate the thermal transport in thorium dioxide at low temperatures.

• Journal of Marine Life Science
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• v.4 no.1
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• pp.22-28
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• 2019

The bacterial diversity of an Antarctic hard coral, Errina fissurata, was examined by isolating bacterial colonies from crushed coral tissue and by sequencing their 16S rRNA gene. From the analyzed results, the bacteria were classified as Actinobacteria (56%), Firmicutes (35%) and Proteobacteria (9%). The thirty-four isolates were cultured in liquid media at different temperatures and their growth was assessed over time. The majority of the isolates displayed their highest growth rate at 25℃ during the first three days of cultivation, even though the coral was from a cold environment. Nevertheless, strains showing their highest growth rate at low temperatures (15℃ and 4℃) were also found. This study reports the composition of an Antarctic hard coral-associated culturable bacterial community and their growth behavior at different temperatures.

• Journal of Biosystems Engineering
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• v.31 no.5 s.118
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• pp.449-453
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• 2006

Effect of light quality on plant temperatures at joining parts of grafted watermelon seedlings was investigated using a thermal imaging system in this study. Plant temperatures at joining parts lowered than those at stem region during graft-taking. However, difference in plant temperatures at joining parts and at stem region decreased by days after graft-taking. Plant temperatures of grafted seedlings graft-taken under white, blue, red, and blue + red fluorescent lamps repeatedly fluctuated high at photoperiod and low at dark period. Considering the variation of plant temperatures at joining pa퍼5, the illumination of blue and red light as well as white light will be effective for grafting of grafted watermelon seedlings. It is recommended that air temperature around grafted seedlings should be maintained at 27 to $29^{\circ}C$ for enhancing the physiological reaction of callus and for the smooth joining of scion and rootstock.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1537-1544
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• 2020

Molecular dynamics (MD) simulations were conducted to investigate the temperature effects on the primary damage in gallium nitride (GaN) material. Five temperatures ranging from 300 K to 900 K were studied for 10 keV Ga primary knock-on atom (PKA) with inject direction of [0001]. The results of MD simulations showed that threshold displacement energy (E_d) was affected by temperatures and at higher temperature, it was larger. The evolutions of defects under various temperatures were similar. However, the higher temperature was found to increase the peak number, peak time, final time and recombination efficiency while decreasing the final number. With regard to clusters, isolated point defects and little clusters were common clusters and the fraction of point defects increased with temperature for vacancy clusters, whereas it did not appear in the interstitial clusters. Finally, at each temperature, the number of Ga interstitial atoms was larger than that of N and besides that, there were other different results of specific types of split interstitial atoms.

• Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.25-34
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• 2013

Early ontogenic development in Siberian sturgeon Acipenser baerii was documented and the effects of different temperatures on embryonic and prelarval development were examined. Photograph-assisted data on morphogenesis in Siberian sturgeon prolarvae agreed well with published descriptions of their ontogeny and ecological behaviors, although certain aspects of differentiation, such as gill covering and scute development, could be rearing condition-sensitive. The present study provides the first characterization of the transient development of teeth during early larval stages; the pattern was congruent with the transition of prolarvae to exogenous feeding. From examinations of embryonic and prelarval development under different temperature conditions ($12-24^{\circ}C$), developmental speed was inversely related with temperature. Overall, hatchability was higher and hatching events were more synchronized at $20^{\circ}C$ than at lower temperatures. After hatching, similar patterns of temperature-dependency were observed in yolk sac absorption and the evacuation of the pigment plug. Our results suggest that the incubation of Siberian sturgeon embryos and prolarvae at temperatures close to $20^{\circ}C$ would be advantageous in hatcheries, based on reductions in the duration and uniformity of egg and prolarval developmental stages.