• Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.161-166
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• 2005

We examined the variation in survival and the respiration and filtration rates of Tresus keenae in response to changes in water temperature and salinity. The survivorship of animals exposed to temperatures below $25^{\circ}C$ for 7 days was $80\%$; however, all test animals died on the fourth day at $28^{\circ}C$. The upper lethal temperature over 7 days was $25.9^{\circ}C$. After exposure to lower temperatures, $93\%$ ofthe animals survived at temperatures over $5^{\circ}C$ for 10 days. Survivorship rapidly decreased below $4^{\circ}C$ with all test animals dying at $2^{\circ}C$ on the eighth day. The $LT_{50}$ over 10 days was $4.8^{\circ}C$. The respiration and filtration rates of T. keenae increased as temperature increased. It is believed that energy consumption increases as a result of the increased respiration rate at temperatures above the upper lethal temperature. At temperatures below the lower lethal temperature, the metabolic rate of T. keenae was substantially lowered. In response to changes in salinity, the survivorship of T. keenae was $90\%$ at 30.2 psu after exposure for 5 days; at below 26.8 psu, all test animals died by the fifth day. The $LS_{50}$ was 29.1 psu. As salinity decreased, both the respiration rate and the filtration rate decreased. At 23.5 psu, the respiration and filtration rates decreased by 48 and $34\%$, respectively. These data have implications for increasing efficiency in the production and management of shellfish aquaculture farms.

• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.79-85
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• 2003

The purpose of this study was to disclose the manufacturing process of activated carbon using coal. It investigated the influences on the physical properties that were manufactured activated carbon by using anthracite coal, bituminous coal under carbonizated and activated condition. The adsorption capacities of organic material were superior when the ash content was lower 5∼10%, and the iodine value was about 1,000 mg/g, the adsorption capacity decreased rapidly when ash content was over 15%. The manufactured activated carbon were found characteristics such as the iodine value was over 1,031 mg/g, the specific surface area was over 1,032 $m^2$/g and the hardness was over 95% under manufacturing conditions which were carbonizated temperature of $600^{\circ}C$( 180 minute), activated temperature of 95$0^{\circ}C$(210 minute) and steam weight of 6 $m\ell$/min.100 g coal.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.489-492
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• 2003

In this paper, we experimented on the deterioration process of power supply cords and analyzed the heating temperature of each part of those cords. We also analyzed the surface states, metallurgical structures surface structures and compositions of the wire melted by over-current. In the results of the analyses, the covering began to be deteriorated from the inside. The heating temperature of extension cord was higher than that of plug body. The dendrite structures appeared at the melted wire. By the SEM and EDS analyses, the dendrite structure showed the growth of copper oxide. We found out the characteristics of PVC insulated flexible cords by over-current from the above experiments and analyses. These results may be useful data in the analyses of deterioration causes of power supply cords.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.06a
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• pp.29-29
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• 2004

Long term observational analysis by climatologists has confirmedthat the global warming is no longer a topic of debate among scientists andpolicy makers. According to the report of IPCC-2001 (Intergovernmental Panelon Climate Change), the global mean surface air temperature is increasinggradually. The reported increase of mean temperature is by 0.6 degree in the end of twentieth century. This could represent severe threat for propertylosses especially due to increase in the number of extreme weather arising out of global warming. period of model integration from 2001 to 2100 using output of ECHAM4/HOPE-G of Max Planet Institute of Meteorology (MPI) for IPCC SRES (Special Report on Emission Scenarios). The main results of this study indicate increase of surface air temperature by 6.20C and precipitation by 2.6% over Korea in the end of 21st century. Simulation results also show that there is increase in daily maximum and minimum temperatures while decrease in diurnal temperature range (DTR). DTR changes are diminished mainly due to relatively rapid increase of daily minimum temperature than that of daily maximumtemperature. It has been observed that increase in precipitation amount anddecrease in the number of rainy days lead to increase of pre precipitationintensity.

• Journal of the Korean Society for Heat Treatment
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• v.22 no.1
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• pp.8-15
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• 2009

Structural studies have been performed on precipitation hardening found in $Ni_{3}Al$ based ordered alloys using transmission electron microscopy (TEM). Tilt experiments by the weak-beam method were made to obtain some information concerning the cross slip mechanism of the superlattice dislocation. The strength of ${\gamma}'-Ni_3$(Al,Ti) increases over the temperature range of experiment by the precipitation of fine $\gamma$ particles. The peak temperature where a maximum strength was obtained shifted to higher temperature. Over the whole temperature range, the interaction between dislocation and $\gamma$ precipitates is attractive. On the temperature range of 773 K to 973 K, the dislocations in ${\gamma}'$ matrix move on (111) primary slip plane. When the applied stress is removed, the dislocations make cross slip into (010) plane, while those in $\gamma$ precipitates remain on the (111) primary slip plane. The increase of high temperature strength in ${\gamma}'-Ni_3$(Al,Ti) containing $\gamma$ precipitates is due to the restraint of cross slip of dislocations from (111) to (010) by the dispersion of disordered $\gamma$ particles.

• Journal of Oriental Medical Thermology
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• v.2 no.1
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• pp.43-48
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• 2003

Obesity is excess body weight, defined as a body mass index (BMI) over 30 kg/m2. or 20% over than relative body weight (RBW). We can consider the surface temperature of obesity patients is related with fat distribution and differs from that of non obesity people. The temperature is measured by using Digital Infrared Thermal Imaging(DITI). DITI was taken on 109 people without any specific disease. Among those subjects, obesity group is 77 and non obesity is 32. We measured the surface temperature by describing regular square on the upper arm, lower arm, palm, upper leg, lower leg, foot, upper abdomen and lower abdomen. The temperature of upper leg, upper abdomen and lower abdomen was low (p<0.001) and that of palm and foot was high (p<0.05) in obesity group. The temperature and the difference of lower arm to palm and lower leg to foot correlated with RBW. These results suggest the surface temperature in obesity group differ remarkably from that in non obesity group.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.5
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• pp.531-538
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• 2007

The effects of temperature, coagulants and pre-chlorination on the removal of turbidity and pathogenic protozoa by coagulation process were investigated using jar test of lab scale. In room temperature ($25^{\circ}C$), protozoa were removed over 1.0log at the proper concentration range of coagulants, and up to over 2log at the optimal concentration of coagulants. Considering the 1.5log target removal for Giardiain the processes of coagulation, sedimentation, and filtration, this results implies that the target could be satisfied. However, the removal of protozoa and turbidity was reduced, and optimal PAC concentration was narrowed in low turbidity and cold temperature ($5^{\circ}C$). These results suggest that the drop of coagulation efficiency may be occurred in winter if the conditions are not optimized. Despite the effect of water temperature, the relation of turbidity and protozoa removal appeared to be good. The various kinds of coagulants did not significantly affected for removals of turbidity and protozoa when the concentrations of $Al_2O_3$ were considered. Prechlorination did not increase or decrease the removal of turbidity and protozoa in optimum condition at room temperature, pH 7, 15mg/L of PAC concentration.

• Transactions of Materials Processing
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• v.12 no.3
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• pp.202-207
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• 2003

In order to examine the springback amount and material properties of aluminum alloy sheets (AL1050 and AL5052) in the warm forming which forms the sheet above the room temperature, the stretch bending and draw bending tests and tensile test in various high temperatures are carried out. The warm forming temperature 15$0^{\circ}C$ is a transition in terms of the material properties: over the forming temperature 15$0^{\circ}C$, them $\sigma$$_{YS}$ , $\sigma$$_{TS}$ , E, K, n, etc. are bigger but $\varepsilon$ and plastic strain ratio are smaller. Below the forming temperature 15$0^{\circ}C$, there are no big differences in material properties as the forming temperature changes. AL5052 sheet has more springback effect than AL1050 sheet. While the springbacks of AL5052 and AL1050 sheets show a big reduction over the warm forming temperature 15$0^{\circ}C$ in the stretch bending test, the springback rapidly reduces in the warm forming temperature 15$0^{\circ}C$-20$0^{\circ}C$ for AL5052 sheet and 20$0^{\circ}C$-25$0^{\circ}C$ for AL1050 sheet in the draw bending test.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.3
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• pp.186-191
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• 2004

The effects of temperature on the growth of larvae of wrinkled swimming crab (Liocarcinus corrugatus) under controlled laboratory conditions of 15, 20 and $24^{\circ}C$ were investigated (33.5 psu: 12L: 12B). Each specimen was maintained individually, the instar size was determined from exuvia, and the survival and intermolt period of each instar were recorded. There were no significant differences (P>0.05) in the survival rates at 15, 20, and $24^{\circ}C.$ Comparison of survival over the first 27 days between the three temperature regimes showed significant differences (P<0.001). The intermolt period increased with the instar number, and was greatly extended at the lowest temperature. The molt increment varied little with temperature, and had a mean value of $21.35\%$ over the whole study. Temperature had little effect on survival and molt increment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.171-171
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• 2009

We have investigated dielectric properties depending on temperature and voltage in organic light-emitting diodes using N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-di-amine (TPD) as an hole transport. We analyzed the Cole-Cole plot of TPD. When the voltage is over 3 V, we found that a radius of Cole-Cole plot and $\beta$ increase as the temperature increases to 65 $^{\circ}C$, However, as the over the 65 $^{\circ}C$, those values decrease. Also, when the voltage is below 3 V, a radius of cole-cole plot and $\beta$ increase with the increased temperature.